yaffs: Import yaffs from Wed May 19 12:46:51 2010 +1200

commit 294ec3ddf9786bddb329646010b165768870ce42
Author: Charles Manning <cdhmanning@gmail.com>
Date:   Wed May 19 12:46:51 2010 +1200

    yaffs: Add python test for O_EXCL

    Check that OEXCL really works according to what's on the box.

    Signed-off-by: Charles Manning <cdhmanning@gmail.com>

Change-Id: Idc6864901461dabfb7648f34db57238cdbbaaa72
Signed-off-by: Arve Hjønnevåg <arve@android.com>

37 files changed, 16153 insertions, 0 deletions

diff --git a/fs/Kconfig b/fs/Kconfig
index 3d185308ec8..0082f66128e 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -174,6 +174,10 @@ source "fs/hfsplus/Kconfig"
 source "fs/befs/Kconfig"
 source "fs/bfs/Kconfig"
 source "fs/efs/Kconfig"
+
+# Patched by YAFFS
+source "fs/yaffs2/Kconfig"
+
 source "fs/jffs2/Kconfig"
 # UBIFS File system configuration
 source "fs/ubifs/Kconfig"
diff --git a/fs/Makefile b/fs/Makefile
index e6ec1d309b1..e8729488414 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -126,3 +126,6 @@ obj-$(CONFIG_BTRFS_FS)		+= btrfs/
 obj-$(CONFIG_GFS2_FS)           += gfs2/
 obj-$(CONFIG_EXOFS_FS)          += exofs/
 obj-$(CONFIG_CEPH_FS)		+= ceph/
+
+# Patched by YAFFS
+obj-$(CONFIG_YAFFS_FS)		+= yaffs2/
diff --git a/fs/yaffs2/Kconfig b/fs/yaffs2/Kconfig
new file mode 100644
index 00000000000..d4363edcdbf
--- /dev/null
+++ b/fs/yaffs2/Kconfig
@@ -0,0 +1,180 @@
+#
+# YAFFS file system configurations
+#
+
+config YAFFS_FS
+	tristate "YAFFS2 file system support"
+	default n
+	depends on MTD_BLOCK
+	select YAFFS_YAFFS1
+	select YAFFS_YAFFS2
+	help
+	  YAFFS2, or Yet Another Flash Filing System, is a filing system
+	  optimised for NAND Flash chips.
+
+	  To compile the YAFFS2 file system support as a module, choose M
+	  here: the module will be called yaffs2.
+
+	  If unsure, say N.
+
+	  Further information on YAFFS2 is available at
+	  <http://www.aleph1.co.uk/yaffs/>.
+
+config YAFFS_YAFFS1
+	bool "512 byte / page devices"
+	depends on YAFFS_FS
+	default y
+	help
+	  Enable YAFFS1 support -- yaffs for 512 byte / page devices
+
+	  Not needed for 2K-page devices.
+
+	  If unsure, say Y.
+
+config YAFFS_9BYTE_TAGS
+	bool "Use older-style on-NAND data format with pageStatus byte"
+	depends on YAFFS_YAFFS1
+	default n
+	help
+
+	  Older-style on-NAND data format has a "pageStatus" byte to record
+	  chunk/page state.  This byte is zero when the page is discarded.
+	  Choose this option if you have existing on-NAND data using this
+	  format that you need to continue to support.  New data written
+	  also uses the older-style format.  Note: Use of this option
+	  generally requires that MTD's oob layout be adjusted to use the
+	  older-style format.  See notes on tags formats and MTD versions
+	  in yaffs_mtdif1.c.
+
+	  If unsure, say N.
+
+config YAFFS_DOES_ECC
+	bool "Lets Yaffs do its own ECC"
+	depends on YAFFS_FS && YAFFS_YAFFS1 && !YAFFS_9BYTE_TAGS
+	default n
+	help
+	  This enables Yaffs to use its own ECC functions instead of using
+	  the ones from the generic MTD-NAND driver.
+
+	  If unsure, say N.
+
+config YAFFS_ECC_WRONG_ORDER
+	bool "Use the same ecc byte order as Steven Hill's nand_ecc.c"
+	depends on YAFFS_FS && YAFFS_DOES_ECC && !YAFFS_9BYTE_TAGS
+	default n
+	help
+	  This makes yaffs_ecc.c use the same ecc byte order as Steven
+	  Hill's nand_ecc.c. If not set, then you get the same ecc byte
+	  order as SmartMedia.
+
+	  If unsure, say N.
+
+config YAFFS_YAFFS2
+	bool "2048 byte (or larger) / page devices"
+	depends on YAFFS_FS
+	default y
+	help
+	  Enable YAFFS2 support -- yaffs for >= 2K bytes per page devices
+
+	  If unsure, say Y.
+
+config YAFFS_AUTO_YAFFS2
+	bool "Autoselect yaffs2 format"
+	depends on YAFFS_YAFFS2
+	default y
+	help
+	  Without this, you need to explicitely use yaffs2 as the file
+	  system type. With this, you can say "yaffs" and yaffs or yaffs2
+	  will be used depending on the device page size (yaffs on
+	  512-byte page devices, yaffs2 on 2K page devices).
+
+	  If unsure, say Y.
+
+config YAFFS_DISABLE_TAGS_ECC
+	bool "Disable YAFFS from doing ECC on tags by default"
+	depends on YAFFS_FS && YAFFS_YAFFS2
+	default n
+	help
+	  This defaults Yaffs to using its own ECC calculations on tags instead of
+	  just relying on the MTD.
+	  This behavior can also be overridden with tags_ecc_on and
+	  tags_ecc_off mount options.
+
+	  If unsure, say N.
+
+
+config YAFFS_DISABLE_WIDE_TNODES
+	bool "Turn off wide tnodes"
+	depends on YAFFS_FS
+	default n
+	help
+	  Wide tnodes are only used for NAND arrays >=32MB for 512-byte
+	  page devices and >=128MB for 2k page devices. They use slightly
+	  more RAM but are faster since they eliminate chunk group
+	  searching.
+
+	  Setting this to 'y' will force tnode width to 16 bits and save
+	  memory but make large arrays slower.
+
+	  If unsure, say N.
+
+config YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+	bool "Force chunk erase check"
+	depends on YAFFS_FS
+	default n
+	help
+          Normally YAFFS only checks chunks before writing until an erased
+	  chunk is found. This helps to detect any partially written
+	  chunks that might have happened due to power loss.
+
+	  Enabling this forces on the test that chunks are erased in flash
+	  before writing to them. This takes more time but is potentially
+	  a bit more secure.
+
+	  Suggest setting Y during development and ironing out driver
+	  issues etc. Suggest setting to N if you want faster writing.
+
+	  If unsure, say Y.
+
+config YAFFS_SHORT_NAMES_IN_RAM
+	bool "Cache short names in RAM"
+	depends on YAFFS_FS
+	default y
+	help
+	  If this config is set, then short names are stored with the
+	  yaffs_Object.  This costs an extra 16 bytes of RAM per object,
+	  but makes look-ups faster.
+
+	  If unsure, say Y.
+
+config YAFFS_EMPTY_LOST_AND_FOUND
+	bool "Empty lost and found on boot"
+	depends on YAFFS_FS
+	default n
+	help
+	  If this is enabled then the contents of lost and found is
+	  automatically dumped at mount.
+
+	  If unsure, say N.
+
+config YAFFS_DISABLE_BLOCK_REFRESHING
+	bool "Disable yaffs2 block refreshing"
+	depends on YAFFS_FS
+	default n
+	help
+	 If this is set, then block refreshing is disabled.
+	 Block refreshing infrequently refreshes the oldest block in
+	 a yaffs2 file system. This mechanism helps to refresh flash to
+	 mitigate against data loss. This is particularly useful for MLC.
+
+	  If unsure, say N.
+
+config YAFFS_DISABLE_BACKGROUND
+	bool "Disable yaffs2 background processing"
+	depends on YAFFS_FS
+	default n
+	help
+	 If this is set, then background processing is disabled.
+	 Background processing makes many foreground activities faster.
+
+	  If unsure, say N.
diff --git a/fs/yaffs2/Makefile b/fs/yaffs2/Makefile
new file mode 100644
index 00000000000..382ee6142cf
--- /dev/null
+++ b/fs/yaffs2/Makefile
@@ -0,0 +1,10 @@
+#
+# Makefile for the linux YAFFS filesystem routines.
+#
+
+obj-$(CONFIG_YAFFS_FS) += yaffs.o
+
+yaffs-y := yaffs_ecc.o yaffs_fs.o yaffs_guts.o yaffs_checkptrw.o
+yaffs-y += yaffs_packedtags1.o yaffs_packedtags2.o yaffs_nand.o yaffs_qsort.o
+yaffs-y += yaffs_tagscompat.o yaffs_tagsvalidity.o
+yaffs-y += yaffs_mtdif.o yaffs_mtdif1.o yaffs_mtdif2.o
diff --git a/fs/yaffs2/devextras.h b/fs/yaffs2/devextras.h
new file mode 100644
index 00000000000..215caa50f17
--- /dev/null
+++ b/fs/yaffs2/devextras.h
@@ -0,0 +1,196 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/*
+ * This file is just holds extra declarations of macros that would normally
+ * be providesd in the Linux kernel. These macros have been written from
+ * scratch but are functionally equivalent to the Linux ones.
+ *
+ */
+
+#ifndef __EXTRAS_H__
+#define __EXTRAS_H__
+
+
+#if !(defined __KERNEL__)
+
+/* Definition of types */
+typedef unsigned char __u8;
+typedef unsigned short __u16;
+typedef unsigned __u32;
+
+#endif
+
+/*
+ * This is a simple doubly linked list implementation that matches the
+ * way the Linux kernel doubly linked list implementation works.
+ */
+
+struct ylist_head {
+	struct ylist_head *next; /* next in chain */
+	struct ylist_head *prev; /* previous in chain */
+};
+
+
+/* Initialise a static list */
+#define YLIST_HEAD(name) \
+struct ylist_head name = { &(name), &(name)}
+
+
+
+/* Initialise a list head to an empty list */
+#define YINIT_LIST_HEAD(p) \
+do { \
+	(p)->next = (p);\
+	(p)->prev = (p); \
+} while (0)
+
+
+/* Add an element to a list */
+static __inline__ void ylist_add(struct ylist_head *newEntry,
+				struct ylist_head *list)
+{
+	struct ylist_head *listNext = list->next;
+
+	list->next = newEntry;
+	newEntry->prev = list;
+	newEntry->next = listNext;
+	listNext->prev = newEntry;
+
+}
+
+static __inline__ void ylist_add_tail(struct ylist_head *newEntry,
+				 struct ylist_head *list)
+{
+	struct ylist_head *listPrev = list->prev;
+
+	list->prev = newEntry;
+	newEntry->next = list;
+	newEntry->prev = listPrev;
+	listPrev->next = newEntry;
+
+}
+
+
+/* Take an element out of its current list, with or without
+ * reinitialising the links.of the entry*/
+static __inline__ void ylist_del(struct ylist_head *entry)
+{
+	struct ylist_head *listNext = entry->next;
+	struct ylist_head *listPrev = entry->prev;
+
+	listNext->prev = listPrev;
+	listPrev->next = listNext;
+
+}
+
+static __inline__ void ylist_del_init(struct ylist_head *entry)
+{
+	ylist_del(entry);
+	entry->next = entry->prev = entry;
+}
+
+
+/* Test if the list is empty */
+static __inline__ int ylist_empty(struct ylist_head *entry)
+{
+	return (entry->next == entry);
+}
+
+
+/* ylist_entry takes a pointer to a list entry and offsets it to that
+ * we can find a pointer to the object it is embedded in.
+ */
+
+
+#define ylist_entry(entry, type, member) \
+	((type *)((char *)(entry)-(unsigned long)(&((type *)NULL)->member)))
+
+
+/* ylist_for_each and list_for_each_safe  iterate over lists.
+ * ylist_for_each_safe uses temporary storage to make the list delete safe
+ */
+
+#define ylist_for_each(itervar, list) \
+	for (itervar = (list)->next; itervar != (list); itervar = itervar->next)
+
+#define ylist_for_each_safe(itervar, saveVar, list) \
+	for (itervar = (list)->next, saveVar = (list)->next->next; \
+		itervar != (list); itervar = saveVar, saveVar = saveVar->next)
+
+
+#if !(defined __KERNEL__)
+
+
+#ifndef WIN32
+#include <sys/stat.h>
+#endif
+
+
+#ifdef CONFIG_YAFFS_PROVIDE_DEFS
+/* File types */
+
+
+#define DT_UNKNOWN	0
+#define DT_FIFO		1
+#define DT_CHR		2
+#define DT_DIR		4
+#define DT_BLK		6
+#define DT_REG		8
+#define DT_LNK		10
+#define DT_SOCK		12
+#define DT_WHT		14
+
+
+#ifndef WIN32
+#include <sys/stat.h>
+#endif
+
+/*
+ * Attribute flags.  These should be or-ed together to figure out what
+ * has been changed!
+ */
+#define ATTR_MODE	1
+#define ATTR_UID	2
+#define ATTR_GID	4
+#define ATTR_SIZE	8
+#define ATTR_ATIME	16
+#define ATTR_MTIME	32
+#define ATTR_CTIME	64
+
+struct iattr {
+	unsigned int ia_valid;
+	unsigned ia_mode;
+	unsigned ia_uid;
+	unsigned ia_gid;
+	unsigned ia_size;
+	unsigned ia_atime;
+	unsigned ia_mtime;
+	unsigned ia_ctime;
+	unsigned int ia_attr_flags;
+};
+
+#endif
+
+#else
+
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+
+#endif
+
+
+#endif
diff --git a/fs/yaffs2/moduleconfig.h b/fs/yaffs2/moduleconfig.h
new file mode 100644
index 00000000000..e8efd67586a
--- /dev/null
+++ b/fs/yaffs2/moduleconfig.h
@@ -0,0 +1,82 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Martin Fouts <Martin.Fouts@palmsource.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_CONFIG_H__
+#define __YAFFS_CONFIG_H__
+
+#ifdef YAFFS_OUT_OF_TREE
+
+/* DO NOT UNSET THESE THREE. YAFFS2 will not compile if you do. */
+#define CONFIG_YAFFS_FS
+#define CONFIG_YAFFS_YAFFS1
+#define CONFIG_YAFFS_YAFFS2
+
+/* These options are independent of each other.  Select those that matter. */
+
+/* Default: Not selected */
+/* Meaning: Yaffs does its own ECC, rather than using MTD ECC */
+/* #define CONFIG_YAFFS_DOES_ECC */
+
+/* Default: Selected */
+/* Meaning: Yaffs does its own ECC on tags for packed tags rather than use mtd */
+#define CONFIG_YAFFS_DOES_TAGS_ECC
+
+/* Default: Not selected */
+/* Meaning: ECC byte order is 'wrong'.  Only meaningful if */
+/*          CONFIG_YAFFS_DOES_ECC is set */
+/* #define CONFIG_YAFFS_ECC_WRONG_ORDER */
+
+/* Default: Not selected */
+/* Meaning: Always test whether chunks are erased before writing to them.
+	    Use during mtd debugging and init. */
+/* #define CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED */
+
+/* Default: Not Selected */
+/* Meaning: At mount automatically empty all files from lost and found. */
+/* This is done to fix an old problem where rmdir was not checking for an */
+/* empty directory. This can also be achieved with a mount option. */
+#define CONFIG_YAFFS_EMPTY_LOST_AND_FOUND
+
+/* Default: Selected */
+/* Meaning: Cache short names, taking more RAM, but faster look-ups */
+#define CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+
+/* Default: Unselected */
+/* Meaning: Select to disable block refreshing. */
+/* Block Refreshing periodically rewrites the oldest block. */
+/* #define CONFIG_DISABLE_BLOCK_REFRESHING */
+
+/* Default: Unselected */
+/* Meaning: Select to disable background processing */
+/* #define CONFIG_DISABLE_BACKGROUND */
+
+
+/*
+Older-style on-NAND data format has a "pageStatus" byte to record
+chunk/page state.  This byte is zeroed when the page is discarded.
+Choose this option if you have existing on-NAND data in this format
+that you need to continue to support.  New data written also uses the
+older-style format.
+Note: Use of this option generally requires that MTD's oob layout be
+adjusted to use the older-style format.  See notes on tags formats and
+MTD versions in yaffs_mtdif1.c.
+*/
+/* Default: Not selected */
+/* Meaning: Use older-style on-NAND data format with pageStatus byte */
+/* #define CONFIG_YAFFS_9BYTE_TAGS */
+
+#endif /* YAFFS_OUT_OF_TREE */
+
+#endif /* __YAFFS_CONFIG_H__ */
diff --git a/fs/yaffs2/yaffs_checkptrw.c b/fs/yaffs2/yaffs_checkptrw.c
new file mode 100644
index 00000000000..1304c19c185
--- /dev/null
+++ b/fs/yaffs2/yaffs_checkptrw.c
@@ -0,0 +1,401 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_checkptrw.h"
+#include "yaffs_getblockinfo.h"
+
+static int yaffs_CheckpointSpaceOk(yaffs_Device *dev)
+{
+	int blocksAvailable = dev->nErasedBlocks - dev->param.nReservedBlocks;
+
+	T(YAFFS_TRACE_CHECKPOINT,
+		(TSTR("checkpt blocks available = %d" TENDSTR),
+		blocksAvailable));
+
+	return (blocksAvailable <= 0) ? 0 : 1;
+}
+
+
+static int yaffs_CheckpointErase(yaffs_Device *dev)
+{
+	int i;
+
+	if (!dev->param.eraseBlockInNAND)
+		return 0;
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checking blocks %d to %d"TENDSTR),
+		dev->internalStartBlock, dev->internalEndBlock));
+
+	for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
+		yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, i);
+		if (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT) {
+			T(YAFFS_TRACE_CHECKPOINT, (TSTR("erasing checkpt block %d"TENDSTR), i));
+
+			dev->nBlockErasures++;
+
+			if (dev->param.eraseBlockInNAND(dev, i - dev->blockOffset /* realign */)) {
+				bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
+				dev->nErasedBlocks++;
+				dev->nFreeChunks += dev->param.nChunksPerBlock;
+			} else {
+				dev->param.markNANDBlockBad(dev, i);
+				bi->blockState = YAFFS_BLOCK_STATE_DEAD;
+			}
+		}
+	}
+
+	dev->blocksInCheckpoint = 0;
+
+	return 1;
+}
+
+
+static void yaffs_CheckpointFindNextErasedBlock(yaffs_Device *dev)
+{
+	int  i;
+	int blocksAvailable = dev->nErasedBlocks - dev->param.nReservedBlocks;
+	T(YAFFS_TRACE_CHECKPOINT,
+		(TSTR("allocating checkpt block: erased %d reserved %d avail %d next %d "TENDSTR),
+		dev->nErasedBlocks, dev->param.nReservedBlocks, blocksAvailable, dev->checkpointNextBlock));
+
+	if (dev->checkpointNextBlock >= 0 &&
+			dev->checkpointNextBlock <= dev->internalEndBlock &&
+			blocksAvailable > 0) {
+
+		for (i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++) {
+			yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, i);
+			if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
+				dev->checkpointNextBlock = i + 1;
+				dev->checkpointCurrentBlock = i;
+				T(YAFFS_TRACE_CHECKPOINT, (TSTR("allocating checkpt block %d"TENDSTR), i));
+				return;
+			}
+		}
+	}
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("out of checkpt blocks"TENDSTR)));
+
+	dev->checkpointNextBlock = -1;
+	dev->checkpointCurrentBlock = -1;
+}
+
+static void yaffs_CheckpointFindNextCheckpointBlock(yaffs_Device *dev)
+{
+	int  i;
+	yaffs_ExtendedTags tags;
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: start:  blocks %d next %d" TENDSTR),
+		dev->blocksInCheckpoint, dev->checkpointNextBlock));
+
+	if (dev->blocksInCheckpoint < dev->checkpointMaxBlocks)
+		for (i = dev->checkpointNextBlock; i <= dev->internalEndBlock; i++) {
+			int chunk = i * dev->param.nChunksPerBlock;
+			int realignedChunk = chunk - dev->chunkOffset;
+
+			dev->param.readChunkWithTagsFromNAND(dev, realignedChunk,
+					NULL, &tags);
+			T(YAFFS_TRACE_CHECKPOINT, (TSTR("find next checkpt block: search: block %d oid %d seq %d eccr %d" TENDSTR),
+				i, tags.objectId, tags.sequenceNumber, tags.eccResult));
+
+			if (tags.sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA) {
+				/* Right kind of block */
+				dev->checkpointNextBlock = tags.objectId;
+				dev->checkpointCurrentBlock = i;
+				dev->checkpointBlockList[dev->blocksInCheckpoint] = i;
+				dev->blocksInCheckpoint++;
+				T(YAFFS_TRACE_CHECKPOINT, (TSTR("found checkpt block %d"TENDSTR), i));
+				return;
+			}
+		}
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("found no more checkpt blocks"TENDSTR)));
+
+	dev->checkpointNextBlock = -1;
+	dev->checkpointCurrentBlock = -1;
+}
+
+
+int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting)
+{
+
+
+	dev->checkpointOpenForWrite = forWriting;
+
+	/* Got the functions we need? */
+	if (!dev->param.writeChunkWithTagsToNAND ||
+		!dev->param.readChunkWithTagsFromNAND ||
+		!dev->param.eraseBlockInNAND ||
+		!dev->param.markNANDBlockBad)
+		return 0;
+
+	if (forWriting && !yaffs_CheckpointSpaceOk(dev))
+		return 0;
+
+	if (!dev->checkpointBuffer)
+		dev->checkpointBuffer = YMALLOC_DMA(dev->param.totalBytesPerChunk);
+	if (!dev->checkpointBuffer)
+		return 0;
+
+
+	dev->checkpointPageSequence = 0;
+	dev->checkpointByteCount = 0;
+	dev->checkpointSum = 0;
+	dev->checkpointXor = 0;
+	dev->checkpointCurrentBlock = -1;
+	dev->checkpointCurrentChunk = -1;
+	dev->checkpointNextBlock = dev->internalStartBlock;
+
+	/* Erase all the blocks in the checkpoint area */
+	if (forWriting) {
+		memset(dev->checkpointBuffer, 0, dev->nDataBytesPerChunk);
+		dev->checkpointByteOffset = 0;
+		return yaffs_CheckpointErase(dev);
+	} else {
+		int i;
+		/* Set to a value that will kick off a read */
+		dev->checkpointByteOffset = dev->nDataBytesPerChunk;
+		/* A checkpoint block list of 1 checkpoint block per 16 block is (hopefully)
+		 * going to be way more than we need */
+		dev->blocksInCheckpoint = 0;
+		dev->checkpointMaxBlocks = (dev->internalEndBlock - dev->internalStartBlock)/16 + 2;
+		dev->checkpointBlockList = YMALLOC(sizeof(int) * dev->checkpointMaxBlocks);
+		if(!dev->checkpointBlockList)
+			return 0;
+
+		for (i = 0; i < dev->checkpointMaxBlocks; i++)
+			dev->checkpointBlockList[i] = -1;
+	}
+
+	return 1;
+}
+
+int yaffs_GetCheckpointSum(yaffs_Device *dev, __u32 *sum)
+{
+	__u32 compositeSum;
+	compositeSum =  (dev->checkpointSum << 8) | (dev->checkpointXor & 0xFF);
+	*sum = compositeSum;
+	return 1;
+}
+
+static int yaffs_CheckpointFlushBuffer(yaffs_Device *dev)
+{
+	int chunk;
+	int realignedChunk;
+
+	yaffs_ExtendedTags tags;
+
+	if (dev->checkpointCurrentBlock < 0) {
+		yaffs_CheckpointFindNextErasedBlock(dev);
+		dev->checkpointCurrentChunk = 0;
+	}
+
+	if (dev->checkpointCurrentBlock < 0)
+		return 0;
+
+	tags.chunkDeleted = 0;
+	tags.objectId = dev->checkpointNextBlock; /* Hint to next place to look */
+	tags.chunkId = dev->checkpointPageSequence + 1;
+	tags.sequenceNumber =  YAFFS_SEQUENCE_CHECKPOINT_DATA;
+	tags.byteCount = dev->nDataBytesPerChunk;
+	if (dev->checkpointCurrentChunk == 0) {
+		/* First chunk we write for the block? Set block state to
+		   checkpoint */
+		yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, dev->checkpointCurrentBlock);
+		bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
+		dev->blocksInCheckpoint++;
+	}
+
+	chunk = dev->checkpointCurrentBlock * dev->param.nChunksPerBlock + dev->checkpointCurrentChunk;
+
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint wite buffer nand %d(%d:%d) objid %d chId %d" TENDSTR),
+		chunk, dev->checkpointCurrentBlock, dev->checkpointCurrentChunk, tags.objectId, tags.chunkId));
+
+	realignedChunk = chunk - dev->chunkOffset;
+
+	dev->nPageWrites++;
+
+	dev->param.writeChunkWithTagsToNAND(dev, realignedChunk,
+			dev->checkpointBuffer, &tags);
+	dev->checkpointByteOffset = 0;
+	dev->checkpointPageSequence++;
+	dev->checkpointCurrentChunk++;
+	if (dev->checkpointCurrentChunk >= dev->param.nChunksPerBlock) {
+		dev->checkpointCurrentChunk = 0;
+		dev->checkpointCurrentBlock = -1;
+	}
+	memset(dev->checkpointBuffer, 0, dev->nDataBytesPerChunk);
+
+	return 1;
+}
+
+
+int yaffs_CheckpointWrite(yaffs_Device *dev, const void *data, int nBytes)
+{
+	int i = 0;
+	int ok = 1;
+
+
+	__u8 * dataBytes = (__u8 *)data;
+
+
+
+	if (!dev->checkpointBuffer)
+		return 0;
+
+	if (!dev->checkpointOpenForWrite)
+		return -1;
+
+	while (i < nBytes && ok) {
+		dev->checkpointBuffer[dev->checkpointByteOffset] = *dataBytes;
+		dev->checkpointSum += *dataBytes;
+		dev->checkpointXor ^= *dataBytes;
+
+		dev->checkpointByteOffset++;
+		i++;
+		dataBytes++;
+		dev->checkpointByteCount++;
+
+
+		if (dev->checkpointByteOffset < 0 ||
+		   dev->checkpointByteOffset >= dev->nDataBytesPerChunk)
+			ok = yaffs_CheckpointFlushBuffer(dev);
+	}
+
+	return i;
+}
+
+int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes)
+{
+	int i = 0;
+	int ok = 1;
+	yaffs_ExtendedTags tags;
+
+
+	int chunk;
+	int realignedChunk;
+
+	__u8 *dataBytes = (__u8 *)data;
+
+	if (!dev->checkpointBuffer)
+		return 0;
+
+	if (dev->checkpointOpenForWrite)
+		return -1;
+
+	while (i < nBytes && ok) {
+
+
+		if (dev->checkpointByteOffset < 0 ||
+			dev->checkpointByteOffset >= dev->nDataBytesPerChunk) {
+
+			if (dev->checkpointCurrentBlock < 0) {
+				yaffs_CheckpointFindNextCheckpointBlock(dev);
+				dev->checkpointCurrentChunk = 0;
+			}
+
+			if (dev->checkpointCurrentBlock < 0)
+				ok = 0;
+			else {
+				chunk = dev->checkpointCurrentBlock *
+					dev->param.nChunksPerBlock +
+					dev->checkpointCurrentChunk;
+
+				realignedChunk = chunk - dev->chunkOffset;
+				
+				dev->nPageReads++;
+
+				/* read in the next chunk */
+				/* printf("read checkpoint page %d\n",dev->checkpointPage); */
+				dev->param.readChunkWithTagsFromNAND(dev,
+						realignedChunk,
+						dev->checkpointBuffer,
+						&tags);
+
+				if (tags.chunkId != (dev->checkpointPageSequence + 1) ||
+					tags.eccResult > YAFFS_ECC_RESULT_FIXED ||
+					tags.sequenceNumber != YAFFS_SEQUENCE_CHECKPOINT_DATA)
+					ok = 0;
+
+				dev->checkpointByteOffset = 0;
+				dev->checkpointPageSequence++;
+				dev->checkpointCurrentChunk++;
+
+				if (dev->checkpointCurrentChunk >= dev->param.nChunksPerBlock)
+					dev->checkpointCurrentBlock = -1;
+			}
+		}
+
+		if (ok) {
+			*dataBytes = dev->checkpointBuffer[dev->checkpointByteOffset];
+			dev->checkpointSum += *dataBytes;
+			dev->checkpointXor ^= *dataBytes;
+			dev->checkpointByteOffset++;
+			i++;
+			dataBytes++;
+			dev->checkpointByteCount++;
+		}
+	}
+
+	return 	i;
+}
+
+int yaffs_CheckpointClose(yaffs_Device *dev)
+{
+
+	if (dev->checkpointOpenForWrite) {
+		if (dev->checkpointByteOffset != 0)
+			yaffs_CheckpointFlushBuffer(dev);
+	} else if(dev->checkpointBlockList){
+		int i;
+		for (i = 0; i < dev->blocksInCheckpoint && dev->checkpointBlockList[i] >= 0; i++) {
+			int blk = dev->checkpointBlockList[i];
+			yaffs_BlockInfo *bi = NULL;
+			if( dev->internalStartBlock <= blk && blk <= dev->internalEndBlock)
+				bi = yaffs_GetBlockInfo(dev, blk);
+			if (bi && bi->blockState == YAFFS_BLOCK_STATE_EMPTY)
+				bi->blockState = YAFFS_BLOCK_STATE_CHECKPOINT;
+			else {
+				/* Todo this looks odd... */
+			}
+		}
+		YFREE(dev->checkpointBlockList);
+		dev->checkpointBlockList = NULL;
+	}
+
+	dev->nFreeChunks -= dev->blocksInCheckpoint * dev->param.nChunksPerBlock;
+	dev->nErasedBlocks -= dev->blocksInCheckpoint;
+
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint byte count %d" TENDSTR),
+			dev->checkpointByteCount));
+
+	if (dev->checkpointBuffer) {
+		/* free the buffer */
+		YFREE(dev->checkpointBuffer);
+		dev->checkpointBuffer = NULL;
+		return 1;
+	} else
+		return 0;
+}
+
+int yaffs_CheckpointInvalidateStream(yaffs_Device *dev)
+{
+	/* Erase the checkpoint data */
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("checkpoint invalidate of %d blocks"TENDSTR),
+		dev->blocksInCheckpoint));
+
+	return yaffs_CheckpointErase(dev);
+}
+
+
+
diff --git a/fs/yaffs2/yaffs_checkptrw.h b/fs/yaffs2/yaffs_checkptrw.h
new file mode 100644
index 00000000000..881c3659c8a
--- /dev/null
+++ b/fs/yaffs2/yaffs_checkptrw.h
@@ -0,0 +1,34 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_CHECKPTRW_H__
+#define __YAFFS_CHECKPTRW_H__
+
+#include "yaffs_guts.h"
+
+int yaffs_CheckpointOpen(yaffs_Device *dev, int forWriting);
+
+int yaffs_CheckpointWrite(yaffs_Device *dev, const void *data, int nBytes);
+
+int yaffs_CheckpointRead(yaffs_Device *dev, void *data, int nBytes);
+
+int yaffs_GetCheckpointSum(yaffs_Device *dev, __u32 *sum);
+
+int yaffs_CheckpointClose(yaffs_Device *dev);
+
+int yaffs_CheckpointInvalidateStream(yaffs_Device *dev);
+
+
+#endif
diff --git a/fs/yaffs2/yaffs_ecc.c b/fs/yaffs2/yaffs_ecc.c
new file mode 100644
index 00000000000..da6145aac27
--- /dev/null
+++ b/fs/yaffs2/yaffs_ecc.c
@@ -0,0 +1,323 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This code implements the ECC algorithm used in SmartMedia.
+ *
+ * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes.
+ * The two unused bit are set to 1.
+ * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC
+ * blocks are used on a 512-byte NAND page.
+ *
+ */
+
+/* Table generated by gen-ecc.c
+ * Using a table means we do not have to calculate p1..p4 and p1'..p4'
+ * for each byte of data. These are instead provided in a table in bits7..2.
+ * Bit 0 of each entry indicates whether the entry has an odd or even parity, and therefore
+ * this bytes influence on the line parity.
+ */
+
+#include "yportenv.h"
+
+#include "yaffs_ecc.h"
+
+static const unsigned char column_parity_table[] = {
+	0x00, 0x55, 0x59, 0x0c, 0x65, 0x30, 0x3c, 0x69,
+	0x69, 0x3c, 0x30, 0x65, 0x0c, 0x59, 0x55, 0x00,
+	0x95, 0xc0, 0xcc, 0x99, 0xf0, 0xa5, 0xa9, 0xfc,
+	0xfc, 0xa9, 0xa5, 0xf0, 0x99, 0xcc, 0xc0, 0x95,
+	0x99, 0xcc, 0xc0, 0x95, 0xfc, 0xa9, 0xa5, 0xf0,
+	0xf0, 0xa5, 0xa9, 0xfc, 0x95, 0xc0, 0xcc, 0x99,
+	0x0c, 0x59, 0x55, 0x00, 0x69, 0x3c, 0x30, 0x65,
+	0x65, 0x30, 0x3c, 0x69, 0x00, 0x55, 0x59, 0x0c,
+	0xa5, 0xf0, 0xfc, 0xa9, 0xc0, 0x95, 0x99, 0xcc,
+	0xcc, 0x99, 0x95, 0xc0, 0xa9, 0xfc, 0xf0, 0xa5,
+	0x30, 0x65, 0x69, 0x3c, 0x55, 0x00, 0x0c, 0x59,
+	0x59, 0x0c, 0x00, 0x55, 0x3c, 0x69, 0x65, 0x30,
+	0x3c, 0x69, 0x65, 0x30, 0x59, 0x0c, 0x00, 0x55,
+	0x55, 0x00, 0x0c, 0x59, 0x30, 0x65, 0x69, 0x3c,
+	0xa9, 0xfc, 0xf0, 0xa5, 0xcc, 0x99, 0x95, 0xc0,
+	0xc0, 0x95, 0x99, 0xcc, 0xa5, 0xf0, 0xfc, 0xa9,
+	0xa9, 0xfc, 0xf0, 0xa5, 0xcc, 0x99, 0x95, 0xc0,
+	0xc0, 0x95, 0x99, 0xcc, 0xa5, 0xf0, 0xfc, 0xa9,
+	0x3c, 0x69, 0x65, 0x30, 0x59, 0x0c, 0x00, 0x55,
+	0x55, 0x00, 0x0c, 0x59, 0x30, 0x65, 0x69, 0x3c,
+	0x30, 0x65, 0x69, 0x3c, 0x55, 0x00, 0x0c, 0x59,
+	0x59, 0x0c, 0x00, 0x55, 0x3c, 0x69, 0x65, 0x30,
+	0xa5, 0xf0, 0xfc, 0xa9, 0xc0, 0x95, 0x99, 0xcc,
+	0xcc, 0x99, 0x95, 0xc0, 0xa9, 0xfc, 0xf0, 0xa5,
+	0x0c, 0x59, 0x55, 0x00, 0x69, 0x3c, 0x30, 0x65,
+	0x65, 0x30, 0x3c, 0x69, 0x00, 0x55, 0x59, 0x0c,
+	0x99, 0xcc, 0xc0, 0x95, 0xfc, 0xa9, 0xa5, 0xf0,
+	0xf0, 0xa5, 0xa9, 0xfc, 0x95, 0xc0, 0xcc, 0x99,
+	0x95, 0xc0, 0xcc, 0x99, 0xf0, 0xa5, 0xa9, 0xfc,
+	0xfc, 0xa9, 0xa5, 0xf0, 0x99, 0xcc, 0xc0, 0x95,
+	0x00, 0x55, 0x59, 0x0c, 0x65, 0x30, 0x3c, 0x69,
+	0x69, 0x3c, 0x30, 0x65, 0x0c, 0x59, 0x55, 0x00,
+};
+
+/* Count the bits in an unsigned char or a U32 */
+
+static int yaffs_CountBits(unsigned char x)
+{
+	int r = 0;
+	while (x) {
+		if (x & 1)
+			r++;
+		x >>= 1;
+	}
+	return r;
+}
+
+static int yaffs_CountBits32(unsigned x)
+{
+	int r = 0;
+	while (x) {
+		if (x & 1)
+			r++;
+		x >>= 1;
+	}
+	return r;
+}
+
+/* Calculate the ECC for a 256-byte block of data */
+void yaffs_ECCCalculate(const unsigned char *data, unsigned char *ecc)
+{
+	unsigned int i;
+
+	unsigned char col_parity = 0;
+	unsigned char line_parity = 0;
+	unsigned char line_parity_prime = 0;
+	unsigned char t;
+	unsigned char b;
+
+	for (i = 0; i < 256; i++) {
+		b = column_parity_table[*data++];
+		col_parity ^= b;
+
+		if (b & 0x01) {		/* odd number of bits in the byte */
+			line_parity ^= i;
+			line_parity_prime ^= ~i;
+		}
+	}
+
+	ecc[2] = (~col_parity) | 0x03;
+
+	t = 0;
+	if (line_parity & 0x80)
+		t |= 0x80;
+	if (line_parity_prime & 0x80)
+		t |= 0x40;
+	if (line_parity & 0x40)
+		t |= 0x20;
+	if (line_parity_prime & 0x40)
+		t |= 0x10;
+	if (line_parity & 0x20)
+		t |= 0x08;
+	if (line_parity_prime & 0x20)
+		t |= 0x04;
+	if (line_parity & 0x10)
+		t |= 0x02;
+	if (line_parity_prime & 0x10)
+		t |= 0x01;
+	ecc[1] = ~t;
+
+	t = 0;
+	if (line_parity & 0x08)
+		t |= 0x80;
+	if (line_parity_prime & 0x08)
+		t |= 0x40;
+	if (line_parity & 0x04)
+		t |= 0x20;
+	if (line_parity_prime & 0x04)
+		t |= 0x10;
+	if (line_parity & 0x02)
+		t |= 0x08;
+	if (line_parity_prime & 0x02)
+		t |= 0x04;
+	if (line_parity & 0x01)
+		t |= 0x02;
+	if (line_parity_prime & 0x01)
+		t |= 0x01;
+	ecc[0] = ~t;
+
+#ifdef CONFIG_YAFFS_ECC_WRONG_ORDER
+	/* Swap the bytes into the wrong order */
+	t = ecc[0];
+	ecc[0] = ecc[1];
+	ecc[1] = t;
+#endif
+}
+
+
+/* Correct the ECC on a 256 byte block of data */
+
+int yaffs_ECCCorrect(unsigned char *data, unsigned char *read_ecc,
+		     const unsigned char *test_ecc)
+{
+	unsigned char d0, d1, d2;	/* deltas */
+
+	d0 = read_ecc[0] ^ test_ecc[0];
+	d1 = read_ecc[1] ^ test_ecc[1];
+	d2 = read_ecc[2] ^ test_ecc[2];
+
+	if ((d0 | d1 | d2) == 0)
+		return 0; /* no error */
+
+	if (((d0 ^ (d0 >> 1)) & 0x55) == 0x55 &&
+	    ((d1 ^ (d1 >> 1)) & 0x55) == 0x55 &&
+	    ((d2 ^ (d2 >> 1)) & 0x54) == 0x54) {
+		/* Single bit (recoverable) error in data */
+
+		unsigned byte;
+		unsigned bit;
+
+#ifdef CONFIG_YAFFS_ECC_WRONG_ORDER
+		/* swap the bytes to correct for the wrong order */
+		unsigned char t;
+
+		t = d0;
+		d0 = d1;
+		d1 = t;
+#endif
+
+		bit = byte = 0;
+
+		if (d1 & 0x80)
+			byte |= 0x80;
+		if (d1 & 0x20)
+			byte |= 0x40;
+		if (d1 & 0x08)
+			byte |= 0x20;
+		if (d1 & 0x02)
+			byte |= 0x10;
+		if (d0 & 0x80)
+			byte |= 0x08;
+		if (d0 & 0x20)
+			byte |= 0x04;
+		if (d0 & 0x08)
+			byte |= 0x02;
+		if (d0 & 0x02)
+			byte |= 0x01;
+
+		if (d2 & 0x80)
+			bit |= 0x04;
+		if (d2 & 0x20)
+			bit |= 0x02;
+		if (d2 & 0x08)
+			bit |= 0x01;
+
+		data[byte] ^= (1 << bit);
+
+		return 1; /* Corrected the error */
+	}
+
+	if ((yaffs_CountBits(d0) +
+	     yaffs_CountBits(d1) +
+	     yaffs_CountBits(d2)) ==  1) {
+		/* Reccoverable error in ecc */
+
+		read_ecc[0] = test_ecc[0];
+		read_ecc[1] = test_ecc[1];
+		read_ecc[2] = test_ecc[2];
+
+		return 1; /* Corrected the error */
+	}
+
+	/* Unrecoverable error */
+
+	return -1;
+
+}
+
+
+/*
+ * ECCxxxOther does ECC calcs on arbitrary n bytes of data
+ */
+void yaffs_ECCCalculateOther(const unsigned char *data, unsigned nBytes,
+				yaffs_ECCOther *eccOther)
+{
+	unsigned int i;
+
+	unsigned char col_parity = 0;
+	unsigned line_parity = 0;
+	unsigned line_parity_prime = 0;
+	unsigned char b;
+
+	for (i = 0; i < nBytes; i++) {
+		b = column_parity_table[*data++];
+		col_parity ^= b;
+
+		if (b & 0x01)	 {
+			/* odd number of bits in the byte */
+			line_parity ^= i;
+			line_parity_prime ^= ~i;
+		}
+
+	}
+
+	eccOther->colParity = (col_parity >> 2) & 0x3f;
+	eccOther->lineParity = line_parity;
+	eccOther->lineParityPrime = line_parity_prime;
+}
+
+int yaffs_ECCCorrectOther(unsigned char *data, unsigned nBytes,
+			yaffs_ECCOther *read_ecc,
+			const yaffs_ECCOther *test_ecc)
+{
+	unsigned char cDelta;	/* column parity delta */
+	unsigned lDelta;	/* line parity delta */
+	unsigned lDeltaPrime;	/* line parity delta */
+	unsigned bit;
+
+	cDelta = read_ecc->colParity ^ test_ecc->colParity;
+	lDelta = read_ecc->lineParity ^ test_ecc->lineParity;
+	lDeltaPrime = read_ecc->lineParityPrime ^ test_ecc->lineParityPrime;
+
+	if ((cDelta | lDelta | lDeltaPrime) == 0)
+		return 0; /* no error */
+
+	if (lDelta == ~lDeltaPrime &&
+	    (((cDelta ^ (cDelta >> 1)) & 0x15) == 0x15)) {
+		/* Single bit (recoverable) error in data */
+
+		bit = 0;
+
+		if (cDelta & 0x20)
+			bit |= 0x04;
+		if (cDelta & 0x08)
+			bit |= 0x02;
+		if (cDelta & 0x02)
+			bit |= 0x01;
+
+		if (lDelta >= nBytes)
+			return -1;
+
+		data[lDelta] ^= (1 << bit);
+
+		return 1; /* corrected */
+	}
+
+	if ((yaffs_CountBits32(lDelta) + yaffs_CountBits32(lDeltaPrime) +
+			yaffs_CountBits(cDelta)) == 1) {
+		/* Reccoverable error in ecc */
+
+		*read_ecc = *test_ecc;
+		return 1; /* corrected */
+	}
+
+	/* Unrecoverable error */
+
+	return -1;
+}
diff --git a/fs/yaffs2/yaffs_ecc.h b/fs/yaffs2/yaffs_ecc.h
new file mode 100644
index 00000000000..a1ee69ac7f2
--- /dev/null
+++ b/fs/yaffs2/yaffs_ecc.h
@@ -0,0 +1,44 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/*
+ * This code implements the ECC algorithm used in SmartMedia.
+ *
+ * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes.
+ * The two unused bit are set to 1.
+ * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC
+ * blocks are used on a 512-byte NAND page.
+ *
+ */
+
+#ifndef __YAFFS_ECC_H__
+#define __YAFFS_ECC_H__
+
+typedef struct {
+	unsigned char colParity;
+	unsigned lineParity;
+	unsigned lineParityPrime;
+} yaffs_ECCOther;
+
+void yaffs_ECCCalculate(const unsigned char *data, unsigned char *ecc);
+int yaffs_ECCCorrect(unsigned char *data, unsigned char *read_ecc,
+		const unsigned char *test_ecc);
+
+void yaffs_ECCCalculateOther(const unsigned char *data, unsigned nBytes,
+			yaffs_ECCOther *ecc);
+int yaffs_ECCCorrectOther(unsigned char *data, unsigned nBytes,
+			yaffs_ECCOther *read_ecc,
+			const yaffs_ECCOther *test_ecc);
+#endif
diff --git a/fs/yaffs2/yaffs_fs.c b/fs/yaffs2/yaffs_fs.c
new file mode 100644
index 00000000000..6eb356c81e6
--- /dev/null
+++ b/fs/yaffs2/yaffs_fs.c
@@ -0,0 +1,3268 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ * Acknowledgements:
+ * Luc van OostenRyck for numerous patches.
+ * Nick Bane for numerous patches.
+ * Nick Bane for 2.5/2.6 integration.
+ * Andras Toth for mknod rdev issue.
+ * Michael Fischer for finding the problem with inode inconsistency.
+ * Some code bodily lifted from JFFS
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ *
+ * This is the file system front-end to YAFFS that hooks it up to
+ * the VFS.
+ *
+ * Special notes:
+ * >> 2.4: sb->u.generic_sbp points to the yaffs_Device associated with
+ *         this superblock
+ * >> 2.6: sb->s_fs_info  points to the yaffs_Device associated with this
+ *         superblock
+ * >> inode->u.generic_ip points to the associated yaffs_Object.
+ */
+
+#include <linux/version.h>
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 10))
+#define YAFFS_COMPILE_BACKGROUND
+#endif
+
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,28))
+#define YAFFS_COMPILE_EXPORTFS
+#endif
+
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19))
+#include <linux/config.h>
+#endif
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/smp_lock.h>
+#include <linux/pagemap.h>
+#include <linux/mtd/mtd.h>
+#include <linux/interrupt.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+
+#ifdef YAFFS_COMPILE_EXPORTFS
+#include <linux/exportfs.h>
+#endif
+
+#ifdef YAFFS_COMPILE_BACKGROUND
+#include <linux/kthread.h>
+#include <linux/delay.h>
+#include <linux/freezer.h>
+#endif
+
+#include <asm/div64.h>
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+
+#include <linux/statfs.h>
+
+#define UnlockPage(p) unlock_page(p)
+#define Page_Uptodate(page)	test_bit(PG_uptodate, &(page)->flags)
+
+/* FIXME: use sb->s_id instead ? */
+#define yaffs_devname(sb, buf)	bdevname(sb->s_bdev, buf)
+
+#else
+
+#include <linux/locks.h>
+#define	BDEVNAME_SIZE		0
+#define	yaffs_devname(sb, buf)	kdevname(sb->s_dev)
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 5, 0))
+/* added NCB 26/5/2006 for 2.4.25-vrs2-tcl1 kernel */
+#define __user
+#endif
+
+#endif
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 26))
+#define YPROC_ROOT  (&proc_root)
+#else
+#define YPROC_ROOT  NULL
+#endif
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+#define WRITE_SIZE_STR "writesize"
+#define WRITE_SIZE(mtd) ((mtd)->writesize)
+#else
+#define WRITE_SIZE_STR "oobblock"
+#define WRITE_SIZE(mtd) ((mtd)->oobblock)
+#endif
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 27))
+#define YAFFS_USE_WRITE_BEGIN_END 1
+#else
+#define YAFFS_USE_WRITE_BEGIN_END 0
+#endif
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 28))
+static uint32_t YCALCBLOCKS(uint64_t partition_size, uint32_t block_size)
+{
+	uint64_t result = partition_size;
+	do_div(result, block_size);
+	return (uint32_t)result;
+}
+#else
+#define YCALCBLOCKS(s, b) ((s)/(b))
+#endif
+
+#include <linux/uaccess.h>
+#include <linux/mtd/mtd.h>
+
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_guts.h"
+
+#include "yaffs_linux.h"
+
+#include "yaffs_mtdif.h"
+#include "yaffs_mtdif1.h"
+#include "yaffs_mtdif2.h"
+
+unsigned int yaffs_traceMask = YAFFS_TRACE_BAD_BLOCKS | YAFFS_TRACE_ALWAYS;
+unsigned int yaffs_wr_attempts = YAFFS_WR_ATTEMPTS;
+unsigned int yaffs_auto_checkpoint = 1;
+unsigned int yaffs_gc_control = 1;
+
+/* Module Parameters */
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+module_param(yaffs_traceMask, uint, 0644);
+module_param(yaffs_wr_attempts, uint, 0644);
+module_param(yaffs_auto_checkpoint, uint, 0644);
+module_param(yaffs_gc_control, uint, 0644);
+#else
+MODULE_PARM(yaffs_traceMask, "i");
+MODULE_PARM(yaffs_wr_attempts, "i");
+MODULE_PARM(yaffs_auto_checkpoint, "i");
+MODULE_PARM(yaffs_gc_control, "i");
+#endif
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 25))
+/* use iget and read_inode */
+#define Y_IGET(sb, inum) iget((sb), (inum))
+static void yaffs_read_inode(struct inode *inode);
+
+#else
+/* Call local equivalent */
+#define YAFFS_USE_OWN_IGET
+#define Y_IGET(sb, inum) yaffs_iget((sb), (inum))
+
+static struct inode *yaffs_iget(struct super_block *sb, unsigned long ino);
+#endif
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 18))
+#define yaffs_InodeToObjectLV(iptr) ((iptr)->i_private)
+#else
+#define yaffs_InodeToObjectLV(iptr) ((iptr)->u.generic_ip)
+#endif
+
+#define yaffs_InodeToObject(iptr) ((yaffs_Object *)(yaffs_InodeToObjectLV(iptr)))
+#define yaffs_DentryToObject(dptr) yaffs_InodeToObject((dptr)->d_inode)
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+#define yaffs_SuperToDevice(sb)	((yaffs_Device *)sb->s_fs_info)
+#else
+#define yaffs_SuperToDevice(sb)	((yaffs_Device *)sb->u.generic_sbp)
+#endif
+
+
+#define update_dir_time(dir) do {\
+			(dir)->i_ctime = (dir)->i_mtime = CURRENT_TIME; \
+		} while(0)
+		
+static void yaffs_put_super(struct super_block *sb);
+
+static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n,
+				loff_t *pos);
+static ssize_t yaffs_hold_space(struct file *f);
+static void yaffs_release_space(struct file *f);
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs_file_flush(struct file *file, fl_owner_t id);
+#else
+static int yaffs_file_flush(struct file *file);
+#endif
+
+static int yaffs_sync_object(struct file *file, struct dentry *dentry,
+				int datasync);
+
+static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir);
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode,
+			struct nameidata *n);
+static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry,
+					struct nameidata *n);
+#else
+static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode);
+static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry);
+#endif
+static int yaffs_link(struct dentry *old_dentry, struct inode *dir,
+			struct dentry *dentry);
+static int yaffs_unlink(struct inode *dir, struct dentry *dentry);
+static int yaffs_symlink(struct inode *dir, struct dentry *dentry,
+			const char *symname);
+static int yaffs_mkdir(struct inode *dir, struct dentry *dentry, int mode);
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
+			dev_t dev);
+#else
+static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
+			int dev);
+#endif
+static int yaffs_rename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry);
+static int yaffs_setattr(struct dentry *dentry, struct iattr *attr);
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs_sync_fs(struct super_block *sb, int wait);
+static void yaffs_write_super(struct super_block *sb);
+#else
+static int yaffs_sync_fs(struct super_block *sb);
+static int yaffs_write_super(struct super_block *sb);
+#endif
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs_statfs(struct dentry *dentry, struct kstatfs *buf);
+#elif (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_statfs(struct super_block *sb, struct kstatfs *buf);
+#else
+static int yaffs_statfs(struct super_block *sb, struct statfs *buf);
+#endif
+
+#ifdef YAFFS_HAS_PUT_INODE
+static void yaffs_put_inode(struct inode *inode);
+#endif
+
+static void yaffs_delete_inode(struct inode *);
+static void yaffs_clear_inode(struct inode *);
+
+static int yaffs_readpage(struct file *file, struct page *page);
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_writepage(struct page *page, struct writeback_control *wbc);
+#else
+static int yaffs_writepage(struct page *page);
+#endif
+
+
+#if (YAFFS_USE_WRITE_BEGIN_END != 0)
+static int yaffs_write_begin(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned flags,
+				struct page **pagep, void **fsdata);
+static int yaffs_write_end(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned copied,
+				struct page *pg, void *fsdadata);
+#else
+static int yaffs_prepare_write(struct file *f, struct page *pg,
+				unsigned offset, unsigned to);
+static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset,
+				unsigned to);
+
+#endif
+
+static int yaffs_readlink(struct dentry *dentry, char __user *buffer,
+				int buflen);
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 13))
+static void *yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
+#else
+static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd);
+#endif
+static loff_t yaffs_dir_llseek(struct file *file, loff_t offset, int origin);
+
+static struct address_space_operations yaffs_file_address_operations = {
+	.readpage = yaffs_readpage,
+	.writepage = yaffs_writepage,
+#if (YAFFS_USE_WRITE_BEGIN_END > 0)
+	.write_begin = yaffs_write_begin,
+	.write_end = yaffs_write_end,
+#else
+	.prepare_write = yaffs_prepare_write,
+	.commit_write = yaffs_commit_write,
+#endif
+};
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 22))
+static const struct file_operations yaffs_file_operations = {
+	.read = do_sync_read,
+	.write = do_sync_write,
+	.aio_read = generic_file_aio_read,
+	.aio_write = generic_file_aio_write,
+	.mmap = generic_file_mmap,
+	.flush = yaffs_file_flush,
+	.fsync = yaffs_sync_object,
+	.splice_read = generic_file_splice_read,
+	.splice_write = generic_file_splice_write,
+	.llseek = generic_file_llseek,
+};
+
+#elif (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 18))
+
+static const struct file_operations yaffs_file_operations = {
+	.read = do_sync_read,
+	.write = do_sync_write,
+	.aio_read = generic_file_aio_read,
+	.aio_write = generic_file_aio_write,
+	.mmap = generic_file_mmap,
+	.flush = yaffs_file_flush,
+	.fsync = yaffs_sync_object,
+	.sendfile = generic_file_sendfile,
+};
+
+#else
+
+static const struct file_operations yaffs_file_operations = {
+	.read = generic_file_read,
+	.write = generic_file_write,
+	.mmap = generic_file_mmap,
+	.flush = yaffs_file_flush,
+	.fsync = yaffs_sync_object,
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+	.sendfile = generic_file_sendfile,
+#endif
+};
+#endif
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25))
+static void zero_user_segment(struct page *page, unsigned start, unsigned end)
+{
+	void * kaddr = kmap_atomic(page, KM_USER0);
+	memset(kaddr + start, 0, end - start);
+	kunmap_atomic(kaddr, KM_USER0);
+	flush_dcache_page(page);
+}
+#endif
+
+
+static const struct inode_operations yaffs_file_inode_operations = {
+	.setattr = yaffs_setattr,
+};
+
+static const struct inode_operations yaffs_symlink_inode_operations = {
+	.readlink = yaffs_readlink,
+	.follow_link = yaffs_follow_link,
+	.setattr = yaffs_setattr,
+};
+
+static const struct inode_operations yaffs_dir_inode_operations = {
+	.create = yaffs_create,
+	.lookup = yaffs_lookup,
+	.link = yaffs_link,
+	.unlink = yaffs_unlink,
+	.symlink = yaffs_symlink,
+	.mkdir = yaffs_mkdir,
+	.rmdir = yaffs_unlink,
+	.mknod = yaffs_mknod,
+	.rename = yaffs_rename,
+	.setattr = yaffs_setattr,
+};
+
+static const struct file_operations yaffs_dir_operations = {
+	.read = generic_read_dir,
+	.readdir = yaffs_readdir,
+	.fsync = yaffs_sync_object,
+	.llseek = yaffs_dir_llseek,
+};
+
+static const struct super_operations yaffs_super_ops = {
+	.statfs = yaffs_statfs,
+
+#ifndef YAFFS_USE_OWN_IGET
+	.read_inode = yaffs_read_inode,
+#endif
+#ifdef YAFFS_HAS_PUT_INODE
+	.put_inode = yaffs_put_inode,
+#endif
+	.put_super = yaffs_put_super,
+	.delete_inode = yaffs_delete_inode,
+	.clear_inode = yaffs_clear_inode,
+	.sync_fs = yaffs_sync_fs,
+	.write_super = yaffs_write_super,
+};
+
+static unsigned yaffs_gc_control_callback(yaffs_Device *dev)
+{
+	return yaffs_gc_control;
+}
+                	                                                                                          	
+static void yaffs_GrossLock(yaffs_Device *dev)
+{
+	T(YAFFS_TRACE_LOCK, (TSTR("yaffs locking %p\n"), current));
+	down(&(yaffs_DeviceToContext(dev)->grossLock));
+	T(YAFFS_TRACE_LOCK, (TSTR("yaffs locked %p\n"), current));
+}
+
+static void yaffs_GrossUnlock(yaffs_Device *dev)
+{
+	T(YAFFS_TRACE_LOCK, (TSTR("yaffs unlocking %p\n"), current));
+	up(&(yaffs_DeviceToContext(dev)->grossLock));
+}
+
+#ifdef YAFFS_COMPILE_EXPORTFS
+
+static struct inode *
+yaffs2_nfs_get_inode(struct super_block *sb, uint64_t ino, uint32_t generation)
+{
+	return Y_IGET(sb, ino);
+}
+
+static struct dentry *
+yaffs2_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type)
+{
+	return generic_fh_to_dentry(sb, fid, fh_len, fh_type, yaffs2_nfs_get_inode) ;
+}
+
+static struct dentry *
+ yaffs2_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type)
+{
+	return generic_fh_to_parent(sb, fid, fh_len, fh_type, yaffs2_nfs_get_inode);
+}
+
+struct dentry *yaffs2_get_parent(struct dentry *dentry)
+{
+
+	struct super_block *sb = dentry->d_inode->i_sb;
+	struct dentry *parent = ERR_PTR(-ENOENT);
+	struct inode *inode;
+	unsigned long parent_ino;
+	yaffs_Object *d_obj;
+	yaffs_Object *parent_obj;
+
+	d_obj = yaffs_InodeToObject(dentry->d_inode);
+
+	if (d_obj) {
+		parent_obj = d_obj->parent;
+		if (parent_obj) {
+			parent_ino = yaffs_GetObjectInode(parent_obj);
+			inode = Y_IGET(sb, parent_ino);
+
+			if (IS_ERR(inode)) {
+				parent = ERR_CAST(inode);
+			} else {
+				parent = d_obtain_alias(inode);
+				if (!IS_ERR(parent)) {
+					parent = ERR_PTR(-ENOMEM);
+					iput(inode);
+				}
+			}
+		}
+	}
+
+	return parent;
+}
+
+/* Just declare a zero structure as a NULL value implies
+ * using the default functions of exportfs.
+ */
+
+static struct export_operations yaffs_export_ops =
+{
+	.fh_to_dentry = yaffs2_fh_to_dentry,
+	.fh_to_parent = yaffs2_fh_to_parent,
+	.get_parent = yaffs2_get_parent,
+} ;
+
+#endif
+
+/*-----------------------------------------------------------------*/
+/* Directory search context allows us to unlock access to yaffs during
+ * filldir without causing problems with the directory being modified.
+ * This is similar to the tried and tested mechanism used in yaffs direct.
+ *
+ * A search context iterates along a doubly linked list of siblings in the
+ * directory. If the iterating object is deleted then this would corrupt
+ * the list iteration, likely causing a crash. The search context avoids
+ * this by using the removeObjectCallback to move the search context to the
+ * next object before the object is deleted.
+ *
+ * Many readdirs (and thus seach conexts) may be alive simulateously so
+ * each yaffs_Device has a list of these.
+ *
+ * A seach context lives for the duration of a readdir.
+ *
+ * All these functions must be called while yaffs is locked.
+ */
+
+struct yaffs_SearchContext {
+	yaffs_Device *dev;
+	yaffs_Object *dirObj;
+	yaffs_Object *nextReturn;
+	struct ylist_head others;
+};
+
+/*
+ * yaffs_NewSearch() creates a new search context, initialises it and
+ * adds it to the device's search context list.
+ *
+ * Called at start of readdir.
+ */
+static struct yaffs_SearchContext * yaffs_NewSearch(yaffs_Object *dir)
+{
+	yaffs_Device *dev = dir->myDev;
+	struct yaffs_SearchContext *sc = YMALLOC(sizeof(struct yaffs_SearchContext));
+	if(sc){
+		sc->dirObj = dir;
+		sc->dev = dev;
+		if( ylist_empty(&sc->dirObj->variant.directoryVariant.children))
+			sc->nextReturn = NULL;
+		else
+			sc->nextReturn = ylist_entry(
+                                dir->variant.directoryVariant.children.next,
+				yaffs_Object,siblings);
+		YINIT_LIST_HEAD(&sc->others);
+		ylist_add(&sc->others,&(yaffs_DeviceToContext(dev)->searchContexts));
+	}
+	return sc;
+}
+
+/*
+ * yaffs_EndSearch() disposes of a search context and cleans up.
+ */
+static void yaffs_EndSearch(struct yaffs_SearchContext * sc)
+{
+	if(sc){
+		ylist_del(&sc->others);
+		YFREE(sc);
+	}
+}
+
+/*
+ * yaffs_SearchAdvance() moves a search context to the next object.
+ * Called when the search iterates or when an object removal causes
+ * the search context to be moved to the next object.
+ */
+static void yaffs_SearchAdvance(struct yaffs_SearchContext *sc)
+{
+        if(!sc)
+                return;
+
+        if( sc->nextReturn == NULL ||
+                ylist_empty(&sc->dirObj->variant.directoryVariant.children))
+                sc->nextReturn = NULL;
+        else {
+                struct ylist_head *next = sc->nextReturn->siblings.next;
+
+                if( next == &sc->dirObj->variant.directoryVariant.children)
+                        sc->nextReturn = NULL; /* end of list */
+                else
+                        sc->nextReturn = ylist_entry(next,yaffs_Object,siblings);
+        }
+}
+
+/*
+ * yaffs_RemoveObjectCallback() is called when an object is unlinked.
+ * We check open search contexts and advance any which are currently
+ * on the object being iterated.
+ */
+static void yaffs_RemoveObjectCallback(yaffs_Object *obj)
+{
+
+        struct ylist_head *i;
+        struct yaffs_SearchContext *sc;
+        struct ylist_head *search_contexts = &(yaffs_DeviceToContext(obj->myDev)->searchContexts);
+
+
+        /* Iterate through the directory search contexts.
+         * If any are currently on the object being removed, then advance
+         * the search context to the next object to prevent a hanging pointer.
+         */
+         ylist_for_each(i, search_contexts) {
+                if (i) {
+                        sc = ylist_entry(i, struct yaffs_SearchContext,others);
+                        if(sc->nextReturn == obj)
+                                yaffs_SearchAdvance(sc);
+                }
+	}
+
+}
+
+
+/*-----------------------------------------------------------------*/
+
+static int yaffs_readlink(struct dentry *dentry, char __user *buffer,
+			int buflen)
+{
+	unsigned char *alias;
+	int ret;
+
+	yaffs_Device *dev = yaffs_DentryToObject(dentry)->myDev;
+
+	yaffs_GrossLock(dev);
+
+	alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
+
+	yaffs_GrossUnlock(dev);
+
+	if (!alias)
+		return -ENOMEM;
+
+	ret = vfs_readlink(dentry, buffer, buflen, alias);
+	kfree(alias);
+	return ret;
+}
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 13))
+static void *yaffs_follow_link(struct dentry *dentry, struct nameidata *nd)
+#else
+static int yaffs_follow_link(struct dentry *dentry, struct nameidata *nd)
+#endif
+{
+	unsigned char *alias;
+	int ret;
+	yaffs_Device *dev = yaffs_DentryToObject(dentry)->myDev;
+
+	yaffs_GrossLock(dev);
+
+	alias = yaffs_GetSymlinkAlias(yaffs_DentryToObject(dentry));
+
+	yaffs_GrossUnlock(dev);
+
+	if (!alias) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = vfs_follow_link(nd, alias);
+	kfree(alias);
+out:
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 13))
+	return ERR_PTR(ret);
+#else
+	return ret;
+#endif
+}
+
+struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,
+				yaffs_Object *obj);
+
+/*
+ * Lookup is used to find objects in the fs
+ */
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+
+static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry,
+				struct nameidata *n)
+#else
+static struct dentry *yaffs_lookup(struct inode *dir, struct dentry *dentry)
+#endif
+{
+	yaffs_Object *obj;
+	struct inode *inode = NULL;	/* NCB 2.5/2.6 needs NULL here */
+
+	yaffs_Device *dev = yaffs_InodeToObject(dir)->myDev;
+
+	if(current != yaffs_DeviceToContext(dev)->readdirProcess)
+		yaffs_GrossLock(dev);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_lookup for %d:%s\n"),
+		yaffs_InodeToObject(dir)->objectId, dentry->d_name.name));
+
+	obj = yaffs_FindObjectByName(yaffs_InodeToObject(dir),
+					dentry->d_name.name);
+
+	obj = yaffs_GetEquivalentObject(obj);	/* in case it was a hardlink */
+
+	/* Can't hold gross lock when calling yaffs_get_inode() */
+	if(current != yaffs_DeviceToContext(dev)->readdirProcess)
+		yaffs_GrossUnlock(dev);
+
+	if (obj) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_lookup found %d\n"), obj->objectId));
+
+		inode = yaffs_get_inode(dir->i_sb, obj->yst_mode, 0, obj);
+
+		if (inode) {
+			T(YAFFS_TRACE_OS,
+				(TSTR("yaffs_loookup dentry \n")));
+/* #if 0 asserted by NCB for 2.5/6 compatability - falls through to
+ * d_add even if NULL inode */
+#if 0
+			/*dget(dentry); // try to solve directory bug */
+			d_add(dentry, inode);
+
+			/* return dentry; */
+			return NULL;
+#endif
+		}
+
+	} else {
+		T(YAFFS_TRACE_OS,(TSTR("yaffs_lookup not found\n")));
+
+	}
+
+/* added NCB for 2.5/6 compatability - forces add even if inode is
+ * NULL which creates dentry hash */
+	d_add(dentry, inode);
+
+	return NULL;
+}
+
+
+#ifdef YAFFS_HAS_PUT_INODE
+
+/* For now put inode is just for debugging
+ * Put inode is called when the inode **structure** is put.
+ */
+static void yaffs_put_inode(struct inode *inode)
+{
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_put_inode: ino %d, count %d\n"), (int)inode->i_ino,
+		atomic_read(&inode->i_count)));
+
+}
+#endif
+
+/* clear is called to tell the fs to release any per-inode data it holds */
+static void yaffs_clear_inode(struct inode *inode)
+{
+	yaffs_Object *obj;
+	yaffs_Device *dev;
+
+	obj = yaffs_InodeToObject(inode);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_clear_inode: ino %d, count %d %s\n"), (int)inode->i_ino,
+		atomic_read(&inode->i_count),
+		obj ? "object exists" : "null object"));
+
+	if (obj) {
+		dev = obj->myDev;
+		yaffs_GrossLock(dev);
+
+		/* Clear the association between the inode and
+		 * the yaffs_Object.
+		 */
+		obj->myInode = NULL;
+		yaffs_InodeToObjectLV(inode) = NULL;
+
+		/* If the object freeing was deferred, then the real
+		 * free happens now.
+		 * This should fix the inode inconsistency problem.
+		 */
+
+		yaffs_HandleDeferedFree(obj);
+
+		yaffs_GrossUnlock(dev);
+	}
+
+}
+
+/* delete is called when the link count is zero and the inode
+ * is put (ie. nobody wants to know about it anymore, time to
+ * delete the file).
+ * NB Must call clear_inode()
+ */
+static void yaffs_delete_inode(struct inode *inode)
+{
+	yaffs_Object *obj = yaffs_InodeToObject(inode);
+	yaffs_Device *dev;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_delete_inode: ino %d, count %d %s\n"), (int)inode->i_ino,
+		atomic_read(&inode->i_count),
+		obj ? "object exists" : "null object"));
+
+	if (obj) {
+		dev = obj->myDev;
+		yaffs_GrossLock(dev);
+		yaffs_DeleteObject(obj);
+		yaffs_GrossUnlock(dev);
+	}
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 13))
+	truncate_inode_pages(&inode->i_data, 0);
+#endif
+	clear_inode(inode);
+}
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs_file_flush(struct file *file, fl_owner_t id)
+#else
+static int yaffs_file_flush(struct file *file)
+#endif
+{
+	yaffs_Object *obj = yaffs_DentryToObject(file->f_dentry);
+
+	yaffs_Device *dev = obj->myDev;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_file_flush object %d (%s)\n"), obj->objectId,
+		obj->dirty ? "dirty" : "clean"));
+
+	yaffs_GrossLock(dev);
+
+	yaffs_FlushFile(obj, 1, 0);
+
+	yaffs_GrossUnlock(dev);
+
+	return 0;
+}
+
+static int yaffs_readpage_nolock(struct file *f, struct page *pg)
+{
+	/* Lifted from jffs2 */
+
+	yaffs_Object *obj;
+	unsigned char *pg_buf;
+	int ret;
+
+	yaffs_Device *dev;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_readpage_nolock at %08x, size %08x\n"),
+		(unsigned)(pg->index << PAGE_CACHE_SHIFT),
+		(unsigned)PAGE_CACHE_SIZE));
+
+	obj = yaffs_DentryToObject(f->f_dentry);
+
+	dev = obj->myDev;
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+	BUG_ON(!PageLocked(pg));
+#else
+	if (!PageLocked(pg))
+		PAGE_BUG(pg);
+#endif
+
+	pg_buf = kmap(pg);
+	/* FIXME: Can kmap fail? */
+
+	yaffs_GrossLock(dev);
+
+	ret = yaffs_ReadDataFromFile(obj, pg_buf,
+				pg->index << PAGE_CACHE_SHIFT,
+				PAGE_CACHE_SIZE);
+
+	yaffs_GrossUnlock(dev);
+
+	if (ret >= 0)
+		ret = 0;
+
+	if (ret) {
+		ClearPageUptodate(pg);
+		SetPageError(pg);
+	} else {
+		SetPageUptodate(pg);
+		ClearPageError(pg);
+	}
+
+	flush_dcache_page(pg);
+	kunmap(pg);
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage_nolock done\n")));
+	return ret;
+}
+
+static int yaffs_readpage_unlock(struct file *f, struct page *pg)
+{
+	int ret = yaffs_readpage_nolock(f, pg);
+	UnlockPage(pg);
+	return ret;
+}
+
+static int yaffs_readpage(struct file *f, struct page *pg)
+{
+	int ret;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage\n")));
+	ret=yaffs_readpage_unlock(f, pg);
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readpage done\n")));
+	return ret;
+}
+
+/* writepage inspired by/stolen from smbfs */
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_writepage(struct page *page, struct writeback_control *wbc)
+#else
+static int yaffs_writepage(struct page *page)
+#endif
+{
+	struct address_space *mapping = page->mapping;
+	struct inode *inode;
+	unsigned long end_index;
+	char *buffer;
+	yaffs_Object *obj;
+	int nWritten = 0;
+	unsigned nBytes;
+	loff_t i_size;
+
+	if (!mapping)
+		BUG();
+	inode = mapping->host;
+	if (!inode)
+		BUG();
+	i_size = i_size_read(inode);
+
+	end_index = i_size >> PAGE_CACHE_SHIFT;
+
+	if(page->index < end_index)
+		nBytes = PAGE_CACHE_SIZE;
+	else {
+		nBytes = i_size & (PAGE_CACHE_SIZE -1);
+
+		if (page->index > end_index || !nBytes) {
+			T(YAFFS_TRACE_OS,
+				(TSTR("yaffs_writepage at %08x, inode size = %08x!!!\n"),
+				(unsigned)(page->index << PAGE_CACHE_SHIFT),
+				(unsigned)inode->i_size));
+			T(YAFFS_TRACE_OS,
+				(TSTR("                -> don't care!!\n")));
+
+			zero_user_segment(page,0,PAGE_CACHE_SIZE);
+			set_page_writeback(page);
+			unlock_page(page);
+			end_page_writeback(page);
+			return 0;
+		}
+	}
+
+	if(nBytes != PAGE_CACHE_SIZE)
+		zero_user_segment(page,nBytes,PAGE_CACHE_SIZE);
+
+	get_page(page);
+
+	buffer = kmap(page);
+
+	obj = yaffs_InodeToObject(inode);
+	yaffs_GrossLock(obj->myDev);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_writepage at %08x, size %08x\n"),
+		(unsigned)(page->index << PAGE_CACHE_SHIFT), nBytes));
+	T(YAFFS_TRACE_OS,
+		(TSTR("writepag0: obj = %05x, ino = %05x\n"),
+		(int)obj->variant.fileVariant.fileSize, (int)inode->i_size));
+
+	nWritten = yaffs_WriteDataToFile(obj, buffer,
+			page->index << PAGE_CACHE_SHIFT, nBytes, 0);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("writepag1: obj = %05x, ino = %05x\n"),
+		(int)obj->variant.fileVariant.fileSize, (int)inode->i_size));
+
+	yaffs_GrossUnlock(obj->myDev);
+
+	kunmap(page);
+	set_page_writeback(page);
+	unlock_page(page);
+	end_page_writeback(page);
+	put_page(page);
+
+	return (nWritten == nBytes) ? 0 : -ENOSPC;
+}
+
+
+#if (YAFFS_USE_WRITE_BEGIN_END > 0)
+static int yaffs_write_begin(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned flags,
+				struct page **pagep, void **fsdata)
+{
+	struct page *pg = NULL;
+	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+
+	int ret = 0;
+	int space_held = 0;
+
+	/* Get a page */
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 28)
+	pg = grab_cache_page_write_begin(mapping, index, flags);
+#else
+	pg = __grab_cache_page(mapping, index);
+#endif
+
+	*pagep = pg;
+	if (!pg) {
+		ret =  -ENOMEM;
+		goto out;
+	}
+	T(YAFFS_TRACE_OS,
+		(TSTR("start yaffs_write_begin index %d(%x) uptodate %d\n"),
+		(int)index,(int)index,Page_Uptodate(pg) ? 1 : 0));
+
+	/* Get fs space */
+	space_held = yaffs_hold_space(filp);
+
+	if (!space_held) {
+		ret = -ENOSPC;
+		goto out;
+	}
+
+	/* Update page if required */
+
+	if (!Page_Uptodate(pg))
+		ret = yaffs_readpage_nolock(filp, pg);
+
+	if (ret)
+		goto out;
+
+	/* Happy path return */
+	T(YAFFS_TRACE_OS, (TSTR("end yaffs_write_begin - ok\n")));
+
+	return 0;
+
+out:
+	T(YAFFS_TRACE_OS,
+		(TSTR("end yaffs_write_begin fail returning %d\n"), ret));
+	if (space_held)
+		yaffs_release_space(filp);
+	if (pg) {
+		unlock_page(pg);
+		page_cache_release(pg);
+	}
+	return ret;
+}
+
+#else
+
+static int yaffs_prepare_write(struct file *f, struct page *pg,
+				unsigned offset, unsigned to)
+{
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_prepair_write\n")));
+
+	if (!Page_Uptodate(pg))
+		return yaffs_readpage_nolock(f, pg);
+	return 0;
+}
+#endif
+
+#if (YAFFS_USE_WRITE_BEGIN_END > 0)
+static int yaffs_write_end(struct file *filp, struct address_space *mapping,
+				loff_t pos, unsigned len, unsigned copied,
+				struct page *pg, void *fsdadata)
+{
+	int ret = 0;
+	void *addr, *kva;
+	uint32_t offset_into_page = pos & (PAGE_CACHE_SIZE - 1);
+
+	kva = kmap(pg);
+	addr = kva + offset_into_page;
+
+	T(YAFFS_TRACE_OS,
+		("yaffs_write_end addr %p pos %x nBytes %d\n",
+		addr,(unsigned)pos, copied));
+
+	ret = yaffs_file_write(filp, addr, copied, &pos);
+
+	if (ret != copied) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_write_end not same size ret %d  copied %d\n"),
+			ret, copied));
+		SetPageError(pg);
+	} else {
+		/* Nothing */
+	}
+
+	kunmap(pg);
+
+	yaffs_release_space(filp);
+	unlock_page(pg);
+	page_cache_release(pg);
+	return ret;
+}
+#else
+
+static int yaffs_commit_write(struct file *f, struct page *pg, unsigned offset,
+				unsigned to)
+{
+	void *addr, *kva;
+
+	loff_t pos = (((loff_t) pg->index) << PAGE_CACHE_SHIFT) + offset;
+	int nBytes = to - offset;
+	int nWritten;
+
+	unsigned spos = pos;
+	unsigned saddr;
+
+	kva = kmap(pg);
+	addr = kva + offset;
+
+	saddr = (unsigned) addr;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_commit_write addr %x pos %x nBytes %d\n"),
+		saddr, spos, nBytes));
+
+	nWritten = yaffs_file_write(f, addr, nBytes, &pos);
+
+	if (nWritten != nBytes) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_commit_write not same size nWritten %d  nBytes %d\n"),
+			nWritten, nBytes));
+		SetPageError(pg);
+	} else {
+		/* Nothing */
+	}
+
+	kunmap(pg);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_commit_write returning %d\n"),
+		nWritten == nBytes ? 0 : nWritten));
+
+	return nWritten == nBytes ? 0 : nWritten;
+}
+#endif
+
+
+static void yaffs_FillInodeFromObject(struct inode *inode, yaffs_Object *obj)
+{
+	if (inode && obj) {
+
+
+		/* Check mode against the variant type and attempt to repair if broken. */
+		__u32 mode = obj->yst_mode;
+		switch (obj->variantType) {
+		case YAFFS_OBJECT_TYPE_FILE:
+			if (!S_ISREG(mode)) {
+				obj->yst_mode &= ~S_IFMT;
+				obj->yst_mode |= S_IFREG;
+			}
+
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			if (!S_ISLNK(mode)) {
+				obj->yst_mode &= ~S_IFMT;
+				obj->yst_mode |= S_IFLNK;
+			}
+
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			if (!S_ISDIR(mode)) {
+				obj->yst_mode &= ~S_IFMT;
+				obj->yst_mode |= S_IFDIR;
+			}
+
+			break;
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+		default:
+			/* TODO? */
+			break;
+		}
+
+		inode->i_flags |= S_NOATIME;
+
+		inode->i_ino = obj->objectId;
+		inode->i_mode = obj->yst_mode;
+		inode->i_uid = obj->yst_uid;
+		inode->i_gid = obj->yst_gid;
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19))
+		inode->i_blksize = inode->i_sb->s_blocksize;
+#endif
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+
+		inode->i_rdev = old_decode_dev(obj->yst_rdev);
+		inode->i_atime.tv_sec = (time_t) (obj->yst_atime);
+		inode->i_atime.tv_nsec = 0;
+		inode->i_mtime.tv_sec = (time_t) obj->yst_mtime;
+		inode->i_mtime.tv_nsec = 0;
+		inode->i_ctime.tv_sec = (time_t) obj->yst_ctime;
+		inode->i_ctime.tv_nsec = 0;
+#else
+		inode->i_rdev = obj->yst_rdev;
+		inode->i_atime = obj->yst_atime;
+		inode->i_mtime = obj->yst_mtime;
+		inode->i_ctime = obj->yst_ctime;
+#endif
+		inode->i_size = yaffs_GetObjectFileLength(obj);
+		inode->i_blocks = (inode->i_size + 511) >> 9;
+
+		inode->i_nlink = yaffs_GetObjectLinkCount(obj);
+
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_FillInode mode %x uid %d gid %d size %d count %d\n"),
+			inode->i_mode, inode->i_uid, inode->i_gid,
+			(int)inode->i_size, atomic_read(&inode->i_count)));
+
+		switch (obj->yst_mode & S_IFMT) {
+		default:	/* fifo, device or socket */
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+			init_special_inode(inode, obj->yst_mode,
+					old_decode_dev(obj->yst_rdev));
+#else
+			init_special_inode(inode, obj->yst_mode,
+					(dev_t) (obj->yst_rdev));
+#endif
+			break;
+		case S_IFREG:	/* file */
+			inode->i_op = &yaffs_file_inode_operations;
+			inode->i_fop = &yaffs_file_operations;
+			inode->i_mapping->a_ops =
+				&yaffs_file_address_operations;
+			break;
+		case S_IFDIR:	/* directory */
+			inode->i_op = &yaffs_dir_inode_operations;
+			inode->i_fop = &yaffs_dir_operations;
+			break;
+		case S_IFLNK:	/* symlink */
+			inode->i_op = &yaffs_symlink_inode_operations;
+			break;
+		}
+
+		yaffs_InodeToObjectLV(inode) = obj;
+
+		obj->myInode = inode;
+
+	} else {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_FileInode invalid parameters\n")));
+	}
+
+}
+
+struct inode *yaffs_get_inode(struct super_block *sb, int mode, int dev,
+				yaffs_Object *obj)
+{
+	struct inode *inode;
+
+	if (!sb) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_get_inode for NULL super_block!!\n")));
+		return NULL;
+
+	}
+
+	if (!obj) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_get_inode for NULL object!!\n")));
+		return NULL;
+
+	}
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_get_inode for object %d\n"), obj->objectId));
+
+	inode = Y_IGET(sb, obj->objectId);
+	if (IS_ERR(inode))
+		return NULL;
+
+	/* NB Side effect: iget calls back to yaffs_read_inode(). */
+	/* iget also increments the inode's i_count */
+	/* NB You can't be holding grossLock or deadlock will happen! */
+
+	return inode;
+}
+
+static ssize_t yaffs_file_write(struct file *f, const char *buf, size_t n,
+				loff_t *pos)
+{
+	yaffs_Object *obj;
+	int nWritten, ipos;
+	struct inode *inode;
+	yaffs_Device *dev;
+
+	obj = yaffs_DentryToObject(f->f_dentry);
+
+	dev = obj->myDev;
+
+	yaffs_GrossLock(dev);
+
+	inode = f->f_dentry->d_inode;
+
+	if (!S_ISBLK(inode->i_mode) && f->f_flags & O_APPEND)
+		ipos = inode->i_size;
+	else
+		ipos = *pos;
+
+	if (!obj)
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_file_write: hey obj is null!\n")));
+	else
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_file_write about to write writing %u(%x) bytes"
+			"to object %d at %d(%x)\n"),
+			(unsigned) n, (unsigned) n, obj->objectId, ipos,ipos));
+
+	nWritten = yaffs_WriteDataToFile(obj, buf, ipos, n, 0);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_file_write: %d(%x) bytes written\n"),
+		(unsigned )n,(unsigned)n));
+
+	if (nWritten > 0) {
+		ipos += nWritten;
+		*pos = ipos;
+		if (ipos > inode->i_size) {
+			inode->i_size = ipos;
+			inode->i_blocks = (ipos + 511) >> 9;
+
+			T(YAFFS_TRACE_OS,
+				(TSTR("yaffs_file_write size updated to %d bytes, "
+				"%d blocks\n"),
+				ipos, (int)(inode->i_blocks)));
+		}
+
+	}
+	yaffs_GrossUnlock(dev);
+	return (nWritten == 0) && (n > 0) ? -ENOSPC : nWritten;
+}
+
+/* Space holding and freeing is done to ensure we have space available for write_begin/end */
+/* For now we just assume few parallel writes and check against a small number. */
+/* Todo: need to do this with a counter to handle parallel reads better */
+
+static ssize_t yaffs_hold_space(struct file *f)
+{
+	yaffs_Object *obj;
+	yaffs_Device *dev;
+
+	int nFreeChunks;
+
+
+	obj = yaffs_DentryToObject(f->f_dentry);
+
+	dev = obj->myDev;
+
+	yaffs_GrossLock(dev);
+
+	nFreeChunks = yaffs_GetNumberOfFreeChunks(dev);
+
+	yaffs_GrossUnlock(dev);
+
+	return (nFreeChunks > 20) ? 1 : 0;
+}
+
+static void yaffs_release_space(struct file *f)
+{
+	yaffs_Object *obj;
+	yaffs_Device *dev;
+
+
+	obj = yaffs_DentryToObject(f->f_dentry);
+
+	dev = obj->myDev;
+
+	yaffs_GrossLock(dev);
+
+
+	yaffs_GrossUnlock(dev);
+}
+
+
+static loff_t yaffs_dir_llseek(struct file *file, loff_t offset, int origin)
+{
+	long long retval;
+
+	lock_kernel();
+
+	switch (origin){
+	case 2:
+		offset += i_size_read(file->f_path.dentry->d_inode);
+		break;
+	case 1:
+		offset += file->f_pos;
+	}
+	retval = -EINVAL;
+
+	if (offset >= 0){
+		if (offset != file->f_pos)
+			file->f_pos = offset;
+
+		retval = offset;
+	}
+	unlock_kernel();
+	return retval;
+}
+
+
+static int yaffs_readdir(struct file *f, void *dirent, filldir_t filldir)
+{
+	yaffs_Object *obj;
+	yaffs_Device *dev;
+        struct yaffs_SearchContext *sc;
+	struct inode *inode = f->f_dentry->d_inode;
+	unsigned long offset, curoffs;
+	yaffs_Object *l;
+        int retVal = 0;
+
+	char name[YAFFS_MAX_NAME_LENGTH + 1];
+
+	obj = yaffs_DentryToObject(f->f_dentry);
+	dev = obj->myDev;
+
+	yaffs_GrossLock(dev);
+
+	yaffs_DeviceToContext(dev)->readdirProcess = current;
+
+	offset = f->f_pos;
+
+        sc = yaffs_NewSearch(obj);
+        if(!sc){
+                retVal = -ENOMEM;
+                goto unlock_out;
+        }
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_readdir: starting at %d\n"), (int)offset));
+
+	if (offset == 0) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_readdir: entry . ino %d \n"),
+			(int)inode->i_ino));
+		yaffs_GrossUnlock(dev);
+		if (filldir(dirent, ".", 1, offset, inode->i_ino, DT_DIR) < 0)
+			goto out;
+		yaffs_GrossLock(dev);
+		offset++;
+		f->f_pos++;
+	}
+	if (offset == 1) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_readdir: entry .. ino %d \n"),
+			(int)f->f_dentry->d_parent->d_inode->i_ino));
+		yaffs_GrossUnlock(dev);
+		if (filldir(dirent, "..", 2, offset,
+			f->f_dentry->d_parent->d_inode->i_ino, DT_DIR) < 0)
+			goto out;
+		yaffs_GrossLock(dev);
+		offset++;
+		f->f_pos++;
+	}
+
+	curoffs = 1;
+
+	/* If the directory has changed since the open or last call to
+	   readdir, rewind to after the 2 canned entries. */
+	if (f->f_version != inode->i_version) {
+		offset = 2;
+		f->f_pos = offset;
+		f->f_version = inode->i_version;
+	}
+
+	while(sc->nextReturn){
+		curoffs++;
+                l = sc->nextReturn;
+		if (curoffs >= offset) {
+                        int this_inode = yaffs_GetObjectInode(l);
+                        int this_type = yaffs_GetObjectType(l);
+
+			yaffs_GetObjectName(l, name,
+					    YAFFS_MAX_NAME_LENGTH + 1);
+			T(YAFFS_TRACE_OS,
+			  (TSTR("yaffs_readdir: %s inode %d\n"),
+			  name, yaffs_GetObjectInode(l)));
+
+                        yaffs_GrossUnlock(dev);
+
+			if (filldir(dirent,
+					name,
+					strlen(name),
+					offset,
+					this_inode,
+					this_type) < 0)
+				goto out;
+
+                        yaffs_GrossLock(dev);
+
+			offset++;
+			f->f_pos++;
+		}
+                yaffs_SearchAdvance(sc);
+	}
+
+unlock_out:
+	yaffs_DeviceToContext(dev)->readdirProcess = NULL;
+
+	yaffs_GrossUnlock(dev);
+out:
+        yaffs_EndSearch(sc);
+
+	return retVal;
+}
+
+
+
+/*
+ * File creation. Allocate an inode, and we're done..
+ */
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 29)
+#define YCRED(x) x
+#else
+#define YCRED(x) (x->cred)
+#endif
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
+			dev_t rdev)
+#else
+static int yaffs_mknod(struct inode *dir, struct dentry *dentry, int mode,
+			int rdev)
+#endif
+{
+	struct inode *inode;
+
+	yaffs_Object *obj = NULL;
+	yaffs_Device *dev;
+
+	yaffs_Object *parent = yaffs_InodeToObject(dir);
+
+	int error = -ENOSPC;
+	uid_t uid = YCRED(current)->fsuid;
+	gid_t gid = (dir->i_mode & S_ISGID) ? dir->i_gid : YCRED(current)->fsgid;
+
+	if ((dir->i_mode & S_ISGID) && S_ISDIR(mode))
+		mode |= S_ISGID;
+
+	if (parent) {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod: parent object %d type %d\n"),
+			parent->objectId, parent->variantType));
+	} else {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod: could not get parent object\n")));
+		return -EPERM;
+	}
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making oject for %s, "
+			"mode %x dev %x\n"),
+			dentry->d_name.name, mode, rdev));
+
+	dev = parent->myDev;
+
+	yaffs_GrossLock(dev);
+
+	switch (mode & S_IFMT) {
+	default:
+		/* Special (socket, fifo, device...) */
+		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making special\n")));
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+		obj = yaffs_MknodSpecial(parent, dentry->d_name.name, mode, uid,
+				gid, old_encode_dev(rdev));
+#else
+		obj = yaffs_MknodSpecial(parent, dentry->d_name.name, mode, uid,
+				gid, rdev);
+#endif
+		break;
+	case S_IFREG:		/* file          */
+		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making file\n")));
+		obj = yaffs_MknodFile(parent, dentry->d_name.name, mode, uid,
+				gid);
+		break;
+	case S_IFDIR:		/* directory */
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod: making directory\n")));
+		obj = yaffs_MknodDirectory(parent, dentry->d_name.name, mode,
+					uid, gid);
+		break;
+	case S_IFLNK:		/* symlink */
+		T(YAFFS_TRACE_OS, (TSTR("yaffs_mknod: making symlink\n")));
+		obj = NULL;	/* Do we ever get here? */
+		break;
+	}
+
+	/* Can not call yaffs_get_inode() with gross lock held */
+	yaffs_GrossUnlock(dev);
+
+	if (obj) {
+		inode = yaffs_get_inode(dir->i_sb, mode, rdev, obj);
+		d_instantiate(dentry, inode);
+		update_dir_time(dir);
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod created object %d count = %d\n"),
+			obj->objectId, atomic_read(&inode->i_count)));
+		error = 0;
+		yaffs_FillInodeFromObject(dir,parent);
+	} else {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_mknod failed making object\n")));
+		error = -ENOMEM;
+	}
+
+	return error;
+}
+
+static int yaffs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+	int retVal;
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_mkdir\n")));
+	retVal = yaffs_mknod(dir, dentry, mode | S_IFDIR, 0);
+	return retVal;
+}
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode,
+			struct nameidata *n)
+#else
+static int yaffs_create(struct inode *dir, struct dentry *dentry, int mode)
+#endif
+{
+	T(YAFFS_TRACE_OS,(TSTR("yaffs_create\n")));
+	return yaffs_mknod(dir, dentry, mode | S_IFREG, 0);
+}
+
+static int yaffs_unlink(struct inode *dir, struct dentry *dentry)
+{
+	int retVal;
+
+	yaffs_Device *dev;
+	yaffs_Object *obj;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_unlink %d:%s\n"),
+		(int)(dir->i_ino),
+		dentry->d_name.name));
+	obj = yaffs_InodeToObject(dir);
+	dev = obj->myDev;
+
+	yaffs_GrossLock(dev);
+
+	retVal = yaffs_Unlink(obj, dentry->d_name.name);
+
+	if (retVal == YAFFS_OK) {
+		dentry->d_inode->i_nlink--;
+		dir->i_version++;
+		yaffs_GrossUnlock(dev);
+		mark_inode_dirty(dentry->d_inode);
+		update_dir_time(dir);
+		return 0;
+	}
+	yaffs_GrossUnlock(dev);
+	return -ENOTEMPTY;
+}
+
+/*
+ * Create a link...
+ */
+static int yaffs_link(struct dentry *old_dentry, struct inode *dir,
+			struct dentry *dentry)
+{
+	struct inode *inode = old_dentry->d_inode;
+	yaffs_Object *obj = NULL;
+	yaffs_Object *link = NULL;
+	yaffs_Device *dev;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_link\n")));
+
+	obj = yaffs_InodeToObject(inode);
+	dev = obj->myDev;
+
+	yaffs_GrossLock(dev);
+
+	if (!S_ISDIR(inode->i_mode))		/* Don't link directories */
+		link = yaffs_Link(yaffs_InodeToObject(dir), dentry->d_name.name,
+			obj);
+
+	if (link) {
+		old_dentry->d_inode->i_nlink = yaffs_GetObjectLinkCount(obj);
+		d_instantiate(dentry, old_dentry->d_inode);
+		atomic_inc(&old_dentry->d_inode->i_count);
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_link link count %d i_count %d\n"),
+			old_dentry->d_inode->i_nlink,
+			atomic_read(&old_dentry->d_inode->i_count)));
+	}
+
+	yaffs_GrossUnlock(dev);
+
+	if (link){
+		update_dir_time(dir);
+		return 0;
+	}
+
+	return -EPERM;
+}
+
+static int yaffs_symlink(struct inode *dir, struct dentry *dentry,
+				const char *symname)
+{
+	yaffs_Object *obj;
+	yaffs_Device *dev;
+	uid_t uid = YCRED(current)->fsuid;
+	gid_t gid = (dir->i_mode & S_ISGID) ? dir->i_gid : YCRED(current)->fsgid;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_symlink\n")));
+
+	dev = yaffs_InodeToObject(dir)->myDev;
+	yaffs_GrossLock(dev);
+	obj = yaffs_MknodSymLink(yaffs_InodeToObject(dir), dentry->d_name.name,
+				S_IFLNK | S_IRWXUGO, uid, gid, symname);
+	yaffs_GrossUnlock(dev);
+
+	if (obj) {
+		struct inode *inode;
+
+		inode = yaffs_get_inode(dir->i_sb, obj->yst_mode, 0, obj);
+		d_instantiate(dentry, inode);
+		update_dir_time(dir);
+		T(YAFFS_TRACE_OS, (TSTR("symlink created OK\n")));
+		return 0;
+	} else {
+		T(YAFFS_TRACE_OS, (TSTR("symlink not created\n")));
+	}
+
+	return -ENOMEM;
+}
+
+static int yaffs_sync_object(struct file *file, struct dentry *dentry,
+				int datasync)
+{
+
+	yaffs_Object *obj;
+	yaffs_Device *dev;
+
+	obj = yaffs_DentryToObject(dentry);
+
+	dev = obj->myDev;
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC,
+		(TSTR("yaffs_sync_object\n")));
+	yaffs_GrossLock(dev);
+	yaffs_FlushFile(obj, 1, datasync);
+	yaffs_GrossUnlock(dev);
+	return 0;
+}
+
+/*
+ * The VFS layer already does all the dentry stuff for rename.
+ *
+ * NB: POSIX says you can rename an object over an old object of the same name
+ */
+static int yaffs_rename(struct inode *old_dir, struct dentry *old_dentry,
+			struct inode *new_dir, struct dentry *new_dentry)
+{
+	yaffs_Device *dev;
+	int retVal = YAFFS_FAIL;
+	yaffs_Object *target;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_rename\n")));
+	dev = yaffs_InodeToObject(old_dir)->myDev;
+
+	yaffs_GrossLock(dev);
+
+	/* Check if the target is an existing directory that is not empty. */
+	target = yaffs_FindObjectByName(yaffs_InodeToObject(new_dir),
+				new_dentry->d_name.name);
+
+
+
+	if (target && target->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
+		!ylist_empty(&target->variant.directoryVariant.children)) {
+
+		T(YAFFS_TRACE_OS, (TSTR("target is non-empty dir\n")));
+
+		retVal = YAFFS_FAIL;
+	} else {
+		/* Now does unlinking internally using shadowing mechanism */
+		T(YAFFS_TRACE_OS, (TSTR("calling yaffs_RenameObject\n")));
+
+		retVal = yaffs_RenameObject(yaffs_InodeToObject(old_dir),
+				old_dentry->d_name.name,
+				yaffs_InodeToObject(new_dir),
+				new_dentry->d_name.name);
+	}
+	yaffs_GrossUnlock(dev);
+
+	if (retVal == YAFFS_OK) {
+		if (target) {
+			new_dentry->d_inode->i_nlink--;
+			mark_inode_dirty(new_dentry->d_inode);
+		}
+		
+		update_dir_time(old_dir);
+		if(old_dir != new_dir)
+			update_dir_time(new_dir);
+		return 0;
+	} else {
+		return -ENOTEMPTY;
+	}
+}
+
+static int yaffs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	struct inode *inode = dentry->d_inode;
+	int error = 0;
+	yaffs_Device *dev;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_setattr of object %d\n"),
+		yaffs_InodeToObject(inode)->objectId));
+
+	/* Fail if a requested resize >= 2GB */		
+	if (attr->ia_valid & ATTR_SIZE &&
+		(attr->ia_size >> 31))
+		error = -EINVAL;
+
+	if (error == 0)
+		error = inode_change_ok(inode, attr);
+	if (error == 0) {
+		int result;
+		if (!error){
+			error = inode_setattr(inode, attr);
+			T(YAFFS_TRACE_OS,(TSTR("inode_setattr called\n")));
+			if (attr->ia_valid & ATTR_SIZE)
+                        	truncate_inode_pages(&inode->i_data,attr->ia_size);
+		}
+		dev = yaffs_InodeToObject(inode)->myDev;
+		if (attr->ia_valid & ATTR_SIZE){
+			T(YAFFS_TRACE_OS,(TSTR("resize to %d(%x)\n"),
+				(int)(attr->ia_size),(int)(attr->ia_size)));
+		}
+		yaffs_GrossLock(dev);
+		result = yaffs_SetAttributes(yaffs_InodeToObject(inode), attr);
+		if(result == YAFFS_OK) {
+			error = 0;
+		} else {
+			error = -EPERM;
+		}
+		yaffs_GrossUnlock(dev);
+
+	}
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_setattr done returning %d\n"),error));
+
+	return error;
+}
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	yaffs_Device *dev = yaffs_DentryToObject(dentry)->myDev;
+	struct super_block *sb = dentry->d_sb;
+#elif (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_statfs(struct super_block *sb, struct kstatfs *buf)
+{
+	yaffs_Device *dev = yaffs_SuperToDevice(sb);
+#else
+static int yaffs_statfs(struct super_block *sb, struct statfs *buf)
+{
+	yaffs_Device *dev = yaffs_SuperToDevice(sb);
+#endif
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_statfs\n")));
+
+	yaffs_GrossLock(dev);
+
+	buf->f_type = YAFFS_MAGIC;
+	buf->f_bsize = sb->s_blocksize;
+	buf->f_namelen = 255;
+
+	if (dev->nDataBytesPerChunk & (dev->nDataBytesPerChunk - 1)) {
+		/* Do this if chunk size is not a power of 2 */
+
+		uint64_t bytesInDev;
+		uint64_t bytesFree;
+
+		bytesInDev = ((uint64_t)((dev->param.endBlock - dev->param.startBlock + 1))) *
+			((uint64_t)(dev->param.nChunksPerBlock * dev->nDataBytesPerChunk));
+
+		do_div(bytesInDev, sb->s_blocksize); /* bytesInDev becomes the number of blocks */
+		buf->f_blocks = bytesInDev;
+
+		bytesFree  = ((uint64_t)(yaffs_GetNumberOfFreeChunks(dev))) *
+			((uint64_t)(dev->nDataBytesPerChunk));
+
+		do_div(bytesFree, sb->s_blocksize);
+
+		buf->f_bfree = bytesFree;
+
+	} else if (sb->s_blocksize > dev->nDataBytesPerChunk) {
+
+		buf->f_blocks =
+			(dev->param.endBlock - dev->param.startBlock + 1) *
+			dev->param.nChunksPerBlock /
+			(sb->s_blocksize / dev->nDataBytesPerChunk);
+		buf->f_bfree =
+			yaffs_GetNumberOfFreeChunks(dev) /
+			(sb->s_blocksize / dev->nDataBytesPerChunk);
+	} else {
+		buf->f_blocks =
+			(dev->param.endBlock - dev->param.startBlock + 1) *
+			dev->param.nChunksPerBlock *
+			(dev->nDataBytesPerChunk / sb->s_blocksize);
+
+		buf->f_bfree =
+			yaffs_GetNumberOfFreeChunks(dev) *
+			(dev->nDataBytesPerChunk / sb->s_blocksize);
+	}
+
+	buf->f_files = 0;
+	buf->f_ffree = 0;
+	buf->f_bavail = buf->f_bfree;
+
+	yaffs_GrossUnlock(dev);
+	return 0;
+}
+
+
+
+static void yaffs_FlushInodes(struct super_block *sb)
+{
+	struct inode *iptr;
+	yaffs_Object *obj;
+	
+	list_for_each_entry(iptr,&sb->s_inodes, i_sb_list){
+		obj = yaffs_InodeToObject(iptr);
+		if(obj){
+			T(YAFFS_TRACE_OS, (TSTR("flushing obj %d\n"),
+				obj->objectId));
+			yaffs_FlushFile(obj,1,0);
+		}
+	}
+}
+
+
+static void yaffs_FlushSuperBlock(struct super_block *sb, int do_checkpoint)
+{
+	yaffs_Device *dev = yaffs_SuperToDevice(sb);	
+	if(!dev)
+		return;
+	
+	yaffs_FlushInodes(sb);
+	yaffs_UpdateDirtyDirectories(dev);
+	yaffs_FlushEntireDeviceCache(dev);
+	if(do_checkpoint)
+		yaffs_CheckpointSave(dev);
+}
+
+
+static unsigned yaffs_bg_gc_urgency(yaffs_Device *dev)
+{
+	unsigned erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+	struct yaffs_LinuxContext *context = yaffs_DeviceToContext(dev);
+	unsigned scatteredFree = 0; /* Free chunks not in an erased block */
+
+	if(erasedChunks < dev->nFreeChunks)
+		scatteredFree = (dev->nFreeChunks - erasedChunks);
+
+	if(!context->bgRunning)
+		return 0;
+	else if(scatteredFree < (dev->param.nChunksPerBlock * 2))
+		return 0;
+	else if(erasedChunks > dev->nFreeChunks/2)
+		return 0;
+	else if(erasedChunks > dev->nFreeChunks/4)
+		return 1;
+	else
+		return 2;
+}
+
+static int yaffs_do_sync_fs(struct super_block *sb,
+				int request_checkpoint)
+{
+
+	yaffs_Device *dev = yaffs_SuperToDevice(sb);
+	unsigned int oneshot_checkpoint = (yaffs_auto_checkpoint & 4);
+	unsigned gc_urgent = yaffs_bg_gc_urgency(dev);
+	int do_checkpoint;
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC | YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs_do_sync_fs: gc-urgency %d %s %s%s\n"),
+		gc_urgent,
+		sb->s_dirt ? "dirty" : "clean",
+		request_checkpoint ? "checkpoint requested" : "no checkpoint",
+		oneshot_checkpoint ? " one-shot" : "" ));
+
+	yaffs_GrossLock(dev);
+	do_checkpoint = ((request_checkpoint && !gc_urgent) ||
+			oneshot_checkpoint) &&
+			!dev->isCheckpointed;
+
+	if (sb->s_dirt || do_checkpoint) {
+		yaffs_FlushSuperBlock(sb, !dev->isCheckpointed && do_checkpoint);
+		sb->s_dirt = 0;
+		if(oneshot_checkpoint)
+			yaffs_auto_checkpoint &= ~4;
+	}
+	yaffs_GrossUnlock(dev);
+
+	return 0;
+}
+
+/*
+ * yaffs background thread functions .
+ * yaffs_BackgroundThread() the thread function
+ * yaffs_BackgroundStart() launches the background thread.
+ * yaffs_BackgroundStop() cleans up the background thread.
+ *
+ * NB: 
+ * The thread should only run after the yaffs is initialised
+ * The thread should be stopped before yaffs is unmounted.
+ * The thread should not do any writing while the fs is in read only.
+ */
+
+#ifdef YAFFS_COMPILE_BACKGROUND
+
+void yaffs_background_waker(unsigned long data)
+{
+	wake_up_process((struct task_struct *)data);
+}
+
+static int yaffs_BackgroundThread(void *data)
+{
+	yaffs_Device *dev = (yaffs_Device *)data;
+	struct yaffs_LinuxContext *context = yaffs_DeviceToContext(dev);
+	unsigned long now = jiffies;
+	unsigned long next_dir_update = now;
+	unsigned long next_gc = now;
+	unsigned long expires;
+	unsigned int urgency;
+
+	int gcResult;
+	struct timer_list timer;
+
+	T(YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs_background starting for dev %p\n"),
+		(void *)dev));
+
+	set_freezable();
+
+	while(context->bgRunning){
+		T(YAFFS_TRACE_BACKGROUND,
+			(TSTR("yaffs_background\n")));
+
+		if(kthread_should_stop())
+			break;
+
+		if(try_to_freeze())
+			continue;
+
+		yaffs_GrossLock(dev);
+
+		now = jiffies;
+
+		if(time_after(now, next_dir_update)){
+			yaffs_UpdateDirtyDirectories(dev);
+			next_dir_update = now + HZ;
+		}
+
+		if(time_after(now,next_gc)){
+			if(!dev->isCheckpointed){
+				urgency = yaffs_bg_gc_urgency(dev);
+				gcResult = yaffs_BackgroundGarbageCollect(dev, urgency);
+				if(urgency > 1)
+					next_gc = now + HZ/20+1;
+				else if(urgency > 0)
+					next_gc = now + HZ/10+1;
+				else
+					next_gc = now + HZ * 2;
+			} else /*
+				* gc not running so set to next_dir_update
+				* to cut down on wake ups
+				*/
+				next_gc = next_dir_update;
+		}
+		yaffs_GrossUnlock(dev);
+#if 1
+		expires = next_dir_update;
+		if (time_before(next_gc,expires))
+			expires = next_gc;
+		if(time_before(expires,now))
+			expires = now + HZ;
+
+		init_timer(&timer);
+		timer.expires = expires+1;
+		timer.data = (unsigned long) current;
+		timer.function = yaffs_background_waker;
+
+                set_current_state(TASK_INTERRUPTIBLE);
+		add_timer(&timer);
+		schedule();
+		del_timer_sync(&timer);
+#else
+		msleep(10);
+#endif
+	}
+
+	return 0;
+}
+
+static int yaffs_BackgroundStart(yaffs_Device *dev)
+{
+	int retval = 0;
+	struct yaffs_LinuxContext *context = yaffs_DeviceToContext(dev);
+
+	context->bgRunning = 1;
+
+	context->bgThread = kthread_run(yaffs_BackgroundThread,
+	                        (void *)dev,"yaffs-bg");
+
+	if(IS_ERR(context->bgThread)){
+		retval = PTR_ERR(context->bgThread);
+		context->bgThread = NULL;
+		context->bgRunning = 0;
+	}
+	return retval;
+}
+
+static void yaffs_BackgroundStop(yaffs_Device *dev)
+{
+	struct yaffs_LinuxContext *ctxt = yaffs_DeviceToContext(dev);
+
+	ctxt->bgRunning = 0;
+
+	if( ctxt->bgThread){
+		kthread_stop(ctxt->bgThread);
+		ctxt->bgThread = NULL;
+	}
+}
+#else
+static int yaffs_BackgroundThread(void *data)
+{
+	return 0;
+}
+
+static int yaffs_BackgroundStart(yaffs_Device *dev)
+{
+	return 0;
+}
+
+static void yaffs_BackgroundStop(yaffs_Device *dev)
+{
+}
+#endif
+
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static void yaffs_write_super(struct super_block *sb)
+#else
+static int yaffs_write_super(struct super_block *sb)
+#endif
+{
+	unsigned request_checkpoint = (yaffs_auto_checkpoint >= 2);
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC | YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs_write_super%s\n"),
+		request_checkpoint ? " checkpt" : ""));
+
+	yaffs_do_sync_fs(sb, request_checkpoint);
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 18))
+	return 0;
+#endif
+}
+
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs_sync_fs(struct super_block *sb, int wait)
+#else
+static int yaffs_sync_fs(struct super_block *sb)
+#endif
+{
+	unsigned request_checkpoint = (yaffs_auto_checkpoint >= 1);
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_SYNC,
+		(TSTR("yaffs_sync_fs%s\n"),
+		request_checkpoint ? " checkpt" : ""));
+
+	yaffs_do_sync_fs(sb, request_checkpoint);
+
+	return 0;
+}
+
+#ifdef YAFFS_USE_OWN_IGET
+
+static struct inode *yaffs_iget(struct super_block *sb, unsigned long ino)
+{
+	struct inode *inode;
+	yaffs_Object *obj;
+	yaffs_Device *dev = yaffs_SuperToDevice(sb);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_iget for %lu\n"), ino));
+
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	/* NB This is called as a side effect of other functions, but
+	 * we had to release the lock to prevent deadlocks, so
+	 * need to lock again.
+	 */
+
+	yaffs_GrossLock(dev);
+
+	obj = yaffs_FindObjectByNumber(dev, inode->i_ino);
+
+	yaffs_FillInodeFromObject(inode, obj);
+
+	yaffs_GrossUnlock(dev);
+
+	unlock_new_inode(inode);
+	return inode;
+}
+
+#else
+
+static void yaffs_read_inode(struct inode *inode)
+{
+	/* NB This is called as a side effect of other functions, but
+	 * we had to release the lock to prevent deadlocks, so
+	 * need to lock again.
+	 */
+
+	yaffs_Object *obj;
+	yaffs_Device *dev = yaffs_SuperToDevice(inode->i_sb);
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_read_inode for %d\n"), (int)inode->i_ino));
+
+	if(current != yaffs_DeviceToContext(dev)->readdirProcess)
+		yaffs_GrossLock(dev);
+
+	obj = yaffs_FindObjectByNumber(dev, inode->i_ino);
+
+	yaffs_FillInodeFromObject(inode, obj);
+
+	if(current != yaffs_DeviceToContext(dev)->readdirProcess)
+		yaffs_GrossUnlock(dev);
+}
+
+#endif
+
+static YLIST_HEAD(yaffs_context_list);
+struct semaphore yaffs_context_lock;
+
+#if 0 /* not used */
+static int yaffs_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+	yaffs_Device    *dev = yaffs_SuperToDevice(sb);
+
+	if (*flags & MS_RDONLY) {
+		struct mtd_info *mtd = yaffs_SuperToDevice(sb)->genericDevice;
+
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_remount_fs: %s: RO\n"), dev->name));
+
+		yaffs_GrossLock(dev);
+
+		yaffs_FlushSuperBlock(sb,1);
+
+		if (mtd->sync)
+			mtd->sync(mtd);
+
+		yaffs_GrossUnlock(dev);
+	} else {
+		T(YAFFS_TRACE_OS,
+			(TSTR("yaffs_remount_fs: %s: RW\n"), dev->name));
+	}
+
+	return 0;
+}
+#endif
+
+static void yaffs_put_super(struct super_block *sb)
+{
+	yaffs_Device *dev = yaffs_SuperToDevice(sb);
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_put_super\n")));
+
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_BACKGROUND,
+		(TSTR("Shutting down yaffs background thread\n")));
+	yaffs_BackgroundStop(dev);
+	T(YAFFS_TRACE_OS | YAFFS_TRACE_BACKGROUND,
+		(TSTR("yaffs background thread shut down\n")));
+
+	yaffs_GrossLock(dev);
+
+	yaffs_FlushSuperBlock(sb,1);
+
+	if (yaffs_DeviceToContext(dev)->putSuperFunc)
+		yaffs_DeviceToContext(dev)->putSuperFunc(sb);
+
+
+	yaffs_Deinitialise(dev);
+
+	yaffs_GrossUnlock(dev);
+
+	down(&yaffs_context_lock);
+	ylist_del_init(&(yaffs_DeviceToContext(dev)->contextList));
+	up(&yaffs_context_lock);
+
+	if (yaffs_DeviceToContext(dev)->spareBuffer) {
+		YFREE(yaffs_DeviceToContext(dev)->spareBuffer);
+		yaffs_DeviceToContext(dev)->spareBuffer = NULL;
+	}
+
+	kfree(dev);
+}
+
+
+static void yaffs_MTDPutSuper(struct super_block *sb)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(yaffs_SuperToDevice(sb))->mtd;
+
+	if (mtd->sync)
+		mtd->sync(mtd);
+
+	put_mtd_device(mtd);
+}
+
+
+static void yaffs_MarkSuperBlockDirty(yaffs_Device *dev)
+{
+	struct super_block *sb = yaffs_DeviceToContext(dev)->superBlock;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_MarkSuperBlockDirty() sb = %p\n"), sb));
+	if (sb)
+		sb->s_dirt = 1;
+}
+
+typedef struct {
+	int inband_tags;
+	int skip_checkpoint_read;
+	int skip_checkpoint_write;
+	int no_cache;
+	int tags_ecc_on;
+	int tags_ecc_overridden;
+	int lazy_loading_enabled;
+	int lazy_loading_overridden;
+	int empty_lost_and_found;
+	int empty_lost_and_found_overridden;
+} yaffs_options;
+
+#define MAX_OPT_LEN 30
+static int yaffs_parse_options(yaffs_options *options, const char *options_str)
+{
+	char cur_opt[MAX_OPT_LEN + 1];
+	int p;
+	int error = 0;
+
+	/* Parse through the options which is a comma seperated list */
+
+	while (options_str && *options_str && !error) {
+		memset(cur_opt, 0, MAX_OPT_LEN + 1);
+		p = 0;
+
+		while(*options_str == ',')
+			options_str++;
+
+		while (*options_str && *options_str != ',') {
+			if (p < MAX_OPT_LEN) {
+				cur_opt[p] = *options_str;
+				p++;
+			}
+			options_str++;
+		}
+
+		if (!strcmp(cur_opt, "inband-tags"))
+			options->inband_tags = 1;
+		else if (!strcmp(cur_opt, "tags-ecc-off")){
+			options->tags_ecc_on = 0;
+			options->tags_ecc_overridden=1;
+		} else if (!strcmp(cur_opt, "tags-ecc-on")){
+			options->tags_ecc_on = 1;
+			options->tags_ecc_overridden = 1;
+		} else if (!strcmp(cur_opt, "lazy-loading-off")){
+			options->lazy_loading_enabled = 0;
+			options->lazy_loading_overridden=1;
+		} else if (!strcmp(cur_opt, "lazy-loading-on")){
+			options->lazy_loading_enabled = 1;
+			options->lazy_loading_overridden = 1;
+		} else if (!strcmp(cur_opt, "empty-lost-and-found-off")){
+			options->empty_lost_and_found = 0;
+			options->empty_lost_and_found_overridden=1;
+		} else if (!strcmp(cur_opt, "empty-lost-and-found-on")){
+			options->empty_lost_and_found = 1;
+			options->empty_lost_and_found_overridden=1;
+		} else if (!strcmp(cur_opt, "no-cache"))
+			options->no_cache = 1;
+		else if (!strcmp(cur_opt, "no-checkpoint-read"))
+			options->skip_checkpoint_read = 1;
+		else if (!strcmp(cur_opt, "no-checkpoint-write"))
+			options->skip_checkpoint_write = 1;
+		else if (!strcmp(cur_opt, "no-checkpoint")) {
+			options->skip_checkpoint_read = 1;
+			options->skip_checkpoint_write = 1;
+		} else {
+			printk(KERN_INFO "yaffs: Bad mount option \"%s\"\n",
+					cur_opt);
+			error = 1;
+		}
+	}
+
+	return error;
+}
+
+static struct super_block *yaffs_internal_read_super(int yaffsVersion,
+						struct super_block *sb,
+						void *data, int silent)
+{
+	int nBlocks;
+	struct inode *inode = NULL;
+	struct dentry *root;
+	yaffs_Device *dev = 0;
+	char devname_buf[BDEVNAME_SIZE + 1];
+	struct mtd_info *mtd;
+	int err;
+	char *data_str = (char *)data;
+	struct yaffs_LinuxContext *context = NULL;
+	yaffs_DeviceParam *param;
+
+	yaffs_options options;
+
+	sb->s_magic = YAFFS_MAGIC;
+	sb->s_op = &yaffs_super_ops;
+	sb->s_flags |= MS_NOATIME;
+
+#ifdef YAFFS_COMPILE_EXPORTFS
+	sb->s_export_op = &yaffs_export_ops;
+#endif
+
+	if (!sb)
+		printk(KERN_INFO "yaffs: sb is NULL\n");
+	else if (!sb->s_dev)
+		printk(KERN_INFO "yaffs: sb->s_dev is NULL\n");
+	else if (!yaffs_devname(sb, devname_buf))
+		printk(KERN_INFO "yaffs: devname is NULL\n");
+	else
+		printk(KERN_INFO "yaffs: dev is %d name is \"%s\"\n",
+		       sb->s_dev,
+		       yaffs_devname(sb, devname_buf));
+
+	if (!data_str)
+		data_str = "";
+
+	printk(KERN_INFO "yaffs: passed flags \"%s\"\n", data_str);
+
+	memset(&options, 0, sizeof(options));
+
+	if (yaffs_parse_options(&options, data_str)) {
+		/* Option parsing failed */
+		return NULL;
+	}
+
+
+	sb->s_blocksize = PAGE_CACHE_SIZE;
+	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_read_super: Using yaffs%d\n"), yaffsVersion));
+	T(YAFFS_TRACE_OS,
+		(TSTR("yaffs_read_super: block size %d\n"),
+		(int)(sb->s_blocksize)));
+
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs: Attempting MTD mount of %u.%u,\"%s\"\n"),
+	       MAJOR(sb->s_dev), MINOR(sb->s_dev),
+	       yaffs_devname(sb, devname_buf)));
+
+	/* Check it's an mtd device..... */
+	if (MAJOR(sb->s_dev) != MTD_BLOCK_MAJOR)
+		return NULL;	/* This isn't an mtd device */
+
+	/* Get the device */
+	mtd = get_mtd_device(NULL, MINOR(sb->s_dev));
+	if (!mtd) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: MTD device #%u doesn't appear to exist\n"),
+			MINOR(sb->s_dev)));
+		return NULL;
+	}
+	/* Check it's NAND */
+	if (mtd->type != MTD_NANDFLASH) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: MTD device is not NAND it's type %d\n"),
+			mtd->type));
+		return NULL;
+	}
+
+	T(YAFFS_TRACE_OS, (TSTR(" erase %p\n"), mtd->erase));
+	T(YAFFS_TRACE_OS, (TSTR(" read %p\n"), mtd->read));
+	T(YAFFS_TRACE_OS, (TSTR(" write %p\n"), mtd->write));
+	T(YAFFS_TRACE_OS, (TSTR(" readoob %p\n"), mtd->read_oob));
+	T(YAFFS_TRACE_OS, (TSTR(" writeoob %p\n"), mtd->write_oob));
+	T(YAFFS_TRACE_OS, (TSTR(" block_isbad %p\n"), mtd->block_isbad));
+	T(YAFFS_TRACE_OS, (TSTR(" block_markbad %p\n"), mtd->block_markbad));
+	T(YAFFS_TRACE_OS, (TSTR(" %s %d\n"), WRITE_SIZE_STR, WRITE_SIZE(mtd)));
+	T(YAFFS_TRACE_OS, (TSTR(" oobsize %d\n"), mtd->oobsize));
+	T(YAFFS_TRACE_OS, (TSTR(" erasesize %d\n"), mtd->erasesize));
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 29)
+	T(YAFFS_TRACE_OS, (TSTR(" size %u\n"), mtd->size));
+#else
+	T(YAFFS_TRACE_OS, (TSTR(" size %lld\n"), mtd->size));
+#endif
+
+#ifdef CONFIG_YAFFS_AUTO_YAFFS2
+
+	if (yaffsVersion == 1 && WRITE_SIZE(mtd) >= 2048) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: auto selecting yaffs2\n")));
+		yaffsVersion = 2;
+	}
+
+	/* Added NCB 26/5/2006 for completeness */
+	if (yaffsVersion == 2 && !options.inband_tags && WRITE_SIZE(mtd) == 512) {
+		T(YAFFS_TRACE_ALWAYS,
+			(TSTR("yaffs: auto selecting yaffs1\n")));
+		yaffsVersion = 1;
+	}
+
+#endif
+
+	if (yaffsVersion == 2) {
+		/* Check for version 2 style functions */
+		if (!mtd->erase ||
+		    !mtd->block_isbad ||
+		    !mtd->block_markbad ||
+		    !mtd->read ||
+		    !mtd->write ||
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+		    !mtd->read_oob || !mtd->write_oob) {
+#else
+		    !mtd->write_ecc ||
+		    !mtd->read_ecc || !mtd->read_oob || !mtd->write_oob) {
+#endif
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not support required "
+			   "functions\n")));
+			return NULL;
+		}
+
+		if ((WRITE_SIZE(mtd) < YAFFS_MIN_YAFFS2_CHUNK_SIZE ||
+		    mtd->oobsize < YAFFS_MIN_YAFFS2_SPARE_SIZE) &&
+		    !options.inband_tags) {
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not have the "
+			   "right page sizes\n")));
+			return NULL;
+		}
+	} else {
+		/* Check for V1 style functions */
+		if (!mtd->erase ||
+		    !mtd->read ||
+		    !mtd->write ||
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+		    !mtd->read_oob || !mtd->write_oob) {
+#else
+		    !mtd->write_ecc ||
+		    !mtd->read_ecc || !mtd->read_oob || !mtd->write_oob) {
+#endif
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not support required "
+			   "functions\n")));
+			return NULL;
+		}
+
+		if (WRITE_SIZE(mtd) < YAFFS_BYTES_PER_CHUNK ||
+		    mtd->oobsize != YAFFS_BYTES_PER_SPARE) {
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: MTD device does not support have the "
+			   "right page sizes\n")));
+			return NULL;
+		}
+	}
+
+	/* OK, so if we got here, we have an MTD that's NAND and looks
+	 * like it has the right capabilities
+	 * Set the yaffs_Device up for mtd
+	 */
+
+	dev = kmalloc(sizeof(yaffs_Device), GFP_KERNEL);
+	context = kmalloc(sizeof(struct yaffs_LinuxContext),GFP_KERNEL);
+	
+	if(!dev || !context ){
+		if(dev)
+			kfree(dev);
+		if(context)
+			kfree(context);
+		dev = NULL;
+		context = NULL;
+	}
+
+	if (!dev) {
+		/* Deep shit could not allocate device structure */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs_read_super: Failed trying to allocate "
+		   "yaffs_Device. \n")));
+		return NULL;
+	}
+	memset(dev, 0, sizeof(yaffs_Device));
+	param = &(dev->param);
+
+	memset(context,0,sizeof(struct yaffs_LinuxContext));
+	dev->context = context;
+	YINIT_LIST_HEAD(&(context->contextList));
+	context->dev = dev;
+	context->superBlock = sb;
+
+	
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+	sb->s_fs_info = dev;
+#else
+	sb->u.generic_sbp = dev;
+#endif
+	
+	yaffs_DeviceToContext(dev)->mtd = mtd;
+	param->name = mtd->name;
+
+	/* Set up the memory size parameters.... */
+
+	nBlocks = YCALCBLOCKS(mtd->size, (YAFFS_CHUNKS_PER_BLOCK * YAFFS_BYTES_PER_CHUNK));
+
+	param->startBlock = 0;
+	param->endBlock = nBlocks - 1;
+	param->nChunksPerBlock = YAFFS_CHUNKS_PER_BLOCK;
+	param->totalBytesPerChunk = YAFFS_BYTES_PER_CHUNK;
+	param->nReservedBlocks = 5;
+	param->nShortOpCaches = (options.no_cache) ? 0 : 10;
+	param->inbandTags = options.inband_tags;
+
+#ifdef CONFIG_YAFFS_DISABLE_LAZY_LOAD
+	param->disableLazyLoad = 1;
+#endif
+	if(options.lazy_loading_overridden)
+		param->disableLazyLoad = !options.lazy_loading_enabled;
+
+#ifdef CONFIG_YAFFS_DISABLE_TAGS_ECC
+	param->noTagsECC = 1;
+#endif
+
+#ifdef CONFIG_YAFFS_DISABLE_BACKGROUND
+#else
+	param->deferDirectoryUpdate = 1;
+#endif
+
+	if(options.tags_ecc_overridden)
+		param->noTagsECC = !options.tags_ecc_on;
+
+#ifdef CONFIG_YAFFS_EMPTY_LOST_AND_FOUND
+	param->emptyLostAndFound = 1;
+#endif
+
+#ifdef CONFIG_YAFFS_DISABLE_BLOCK_REFRESHING
+	param->refreshPeriod = 0;
+#else
+	param->refreshPeriod = 500;
+#endif
+
+	if(options.empty_lost_and_found_overridden)
+		param->emptyLostAndFound = options.empty_lost_and_found;
+
+	/* ... and the functions. */
+	if (yaffsVersion == 2) {
+		param->writeChunkWithTagsToNAND =
+		    nandmtd2_WriteChunkWithTagsToNAND;
+		param->readChunkWithTagsFromNAND =
+		    nandmtd2_ReadChunkWithTagsFromNAND;
+		param->markNANDBlockBad = nandmtd2_MarkNANDBlockBad;
+		param->queryNANDBlock = nandmtd2_QueryNANDBlock;
+		yaffs_DeviceToContext(dev)->spareBuffer = YMALLOC(mtd->oobsize);
+		param->isYaffs2 = 1;
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+		param->totalBytesPerChunk = mtd->writesize;
+		param->nChunksPerBlock = mtd->erasesize / mtd->writesize;
+#else
+		param->totalBytesPerChunk = mtd->oobblock;
+		param->nChunksPerBlock = mtd->erasesize / mtd->oobblock;
+#endif
+		nBlocks = YCALCBLOCKS(mtd->size, mtd->erasesize);
+
+		param->startBlock = 0;
+		param->endBlock = nBlocks - 1;
+	} else {
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+		/* use the MTD interface in yaffs_mtdif1.c */
+		param->writeChunkWithTagsToNAND =
+			nandmtd1_WriteChunkWithTagsToNAND;
+		param->readChunkWithTagsFromNAND =
+			nandmtd1_ReadChunkWithTagsFromNAND;
+		param->markNANDBlockBad = nandmtd1_MarkNANDBlockBad;
+		param->queryNANDBlock = nandmtd1_QueryNANDBlock;
+#else
+		param->writeChunkToNAND = nandmtd_WriteChunkToNAND;
+		param->readChunkFromNAND = nandmtd_ReadChunkFromNAND;
+#endif
+		param->isYaffs2 = 0;
+	}
+	/* ... and common functions */
+	param->eraseBlockInNAND = nandmtd_EraseBlockInNAND;
+	param->initialiseNAND = nandmtd_InitialiseNAND;
+
+	yaffs_DeviceToContext(dev)->putSuperFunc = yaffs_MTDPutSuper;
+
+	param->markSuperBlockDirty = yaffs_MarkSuperBlockDirty;
+	param->gcControl = yaffs_gc_control_callback;
+
+	yaffs_DeviceToContext(dev)->superBlock= sb;
+	
+
+#ifndef CONFIG_YAFFS_DOES_ECC
+	param->useNANDECC = 1;
+#endif
+
+#ifdef CONFIG_YAFFS_DISABLE_WIDE_TNODES
+	param->wideTnodesDisabled = 1;
+#endif
+
+	param->skipCheckpointRead = options.skip_checkpoint_read;
+	param->skipCheckpointWrite = options.skip_checkpoint_write;
+
+	/* we assume this is protected by lock_kernel() in mount/umount */
+	down(&yaffs_context_lock);
+	ylist_add_tail(&(yaffs_DeviceToContext(dev)->contextList), &yaffs_context_list);
+	up(&yaffs_context_lock);
+
+        /* Directory search handling...*/
+        YINIT_LIST_HEAD(&(yaffs_DeviceToContext(dev)->searchContexts));
+        param->removeObjectCallback = yaffs_RemoveObjectCallback;
+
+	init_MUTEX(&(yaffs_DeviceToContext(dev)->grossLock));
+
+	yaffs_GrossLock(dev);
+
+	err = yaffs_GutsInitialise(dev);
+
+	T(YAFFS_TRACE_OS,
+	  (TSTR("yaffs_read_super: guts initialised %s\n"),
+	   (err == YAFFS_OK) ? "OK" : "FAILED"));
+	   
+	if(err == YAFFS_OK)
+		yaffs_BackgroundStart(dev);
+		
+	if(!context->bgThread)
+		param->deferDirectoryUpdate = 0;
+
+
+	/* Release lock before yaffs_get_inode() */
+	yaffs_GrossUnlock(dev);
+
+	/* Create root inode */
+	if (err == YAFFS_OK)
+		inode = yaffs_get_inode(sb, S_IFDIR | 0755, 0,
+					yaffs_Root(dev));
+
+	if (!inode)
+		return NULL;
+
+	inode->i_op = &yaffs_dir_inode_operations;
+	inode->i_fop = &yaffs_dir_operations;
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: got root inode\n")));
+
+	root = d_alloc_root(inode);
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: d_alloc_root done\n")));
+
+	if (!root) {
+		iput(inode);
+		return NULL;
+	}
+	sb->s_root = root;
+	sb->s_dirt = !dev->isCheckpointed;
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs_read_super: isCheckpointed %d\n"),
+		dev->isCheckpointed));
+
+	T(YAFFS_TRACE_OS, (TSTR("yaffs_read_super: done\n")));
+	return sb;
+}
+
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs_internal_read_super_mtd(struct super_block *sb, void *data,
+					 int silent)
+{
+	return yaffs_internal_read_super(1, sb, data, silent) ? 0 : -EINVAL;
+}
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs_read_super(struct file_system_type *fs,
+			    int flags, const char *dev_name,
+			    void *data, struct vfsmount *mnt)
+{
+
+	return get_sb_bdev(fs, flags, dev_name, data,
+			   yaffs_internal_read_super_mtd, mnt);
+}
+#else
+static struct super_block *yaffs_read_super(struct file_system_type *fs,
+					    int flags, const char *dev_name,
+					    void *data)
+{
+
+	return get_sb_bdev(fs, flags, dev_name, data,
+			   yaffs_internal_read_super_mtd);
+}
+#endif
+
+static struct file_system_type yaffs_fs_type = {
+	.owner = THIS_MODULE,
+	.name = "yaffs",
+	.get_sb = yaffs_read_super,
+	.kill_sb = kill_block_super,
+	.fs_flags = FS_REQUIRES_DEV,
+};
+#else
+static struct super_block *yaffs_read_super(struct super_block *sb, void *data,
+					    int silent)
+{
+	return yaffs_internal_read_super(1, sb, data, silent);
+}
+
+static DECLARE_FSTYPE(yaffs_fs_type, "yaffs", yaffs_read_super,
+		      FS_REQUIRES_DEV);
+#endif
+
+
+#ifdef CONFIG_YAFFS_YAFFS2
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+static int yaffs2_internal_read_super_mtd(struct super_block *sb, void *data,
+					  int silent)
+{
+	return yaffs_internal_read_super(2, sb, data, silent) ? 0 : -EINVAL;
+}
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+static int yaffs2_read_super(struct file_system_type *fs,
+			int flags, const char *dev_name, void *data,
+			struct vfsmount *mnt)
+{
+	return get_sb_bdev(fs, flags, dev_name, data,
+			yaffs2_internal_read_super_mtd, mnt);
+}
+#else
+static struct super_block *yaffs2_read_super(struct file_system_type *fs,
+					     int flags, const char *dev_name,
+					     void *data)
+{
+
+	return get_sb_bdev(fs, flags, dev_name, data,
+			   yaffs2_internal_read_super_mtd);
+}
+#endif
+
+static struct file_system_type yaffs2_fs_type = {
+	.owner = THIS_MODULE,
+	.name = "yaffs2",
+	.get_sb = yaffs2_read_super,
+	.kill_sb = kill_block_super,
+	.fs_flags = FS_REQUIRES_DEV,
+};
+#else
+static struct super_block *yaffs2_read_super(struct super_block *sb,
+					     void *data, int silent)
+{
+	return yaffs_internal_read_super(2, sb, data, silent);
+}
+
+static DECLARE_FSTYPE(yaffs2_fs_type, "yaffs2", yaffs2_read_super,
+		      FS_REQUIRES_DEV);
+#endif
+
+#endif				/* CONFIG_YAFFS_YAFFS2 */
+
+static struct proc_dir_entry *my_proc_entry;
+static struct proc_dir_entry *debug_proc_entry;
+
+static char *yaffs_dump_dev_part0(char *buf, yaffs_Device * dev)
+{
+	buf += sprintf(buf, "startBlock......... %d\n", dev->param.startBlock);
+	buf += sprintf(buf, "endBlock........... %d\n", dev->param.endBlock);
+	buf += sprintf(buf, "totalBytesPerChunk. %d\n", dev->param.totalBytesPerChunk);
+	buf += sprintf(buf, "useNANDECC......... %d\n", dev->param.useNANDECC);
+	buf += sprintf(buf, "noTagsECC.......... %d\n", dev->param.noTagsECC);
+	buf += sprintf(buf, "isYaffs2........... %d\n", dev->param.isYaffs2);
+	buf += sprintf(buf, "inbandTags......... %d\n", dev->param.inbandTags);
+	buf += sprintf(buf, "emptyLostAndFound.. %d\n", dev->param.emptyLostAndFound);
+	buf += sprintf(buf, "disableLazyLoad.... %d\n", dev->param.disableLazyLoad);
+	buf += sprintf(buf, "refreshPeriod...... %d\n", dev->param.refreshPeriod);
+	buf += sprintf(buf, "nShortOpCaches..... %d\n", dev->param.nShortOpCaches);
+	buf += sprintf(buf, "nReservedBlocks.... %d\n", dev->param.nReservedBlocks);
+
+	buf += sprintf(buf, "\n");
+
+	return buf;
+}
+
+
+static char *yaffs_dump_dev_part1(char *buf, yaffs_Device * dev)
+{
+	buf += sprintf(buf, "nDataBytesPerChunk. %d\n", dev->nDataBytesPerChunk);
+	buf += sprintf(buf, "chunkGroupBits..... %d\n", dev->chunkGroupBits);
+	buf += sprintf(buf, "chunkGroupSize..... %d\n", dev->chunkGroupSize);
+	buf += sprintf(buf, "nErasedBlocks...... %d\n", dev->nErasedBlocks);
+	buf += sprintf(buf, "blocksInCheckpoint. %d\n", dev->blocksInCheckpoint);
+	buf += sprintf(buf, "\n");
+	buf += sprintf(buf, "nTnodesCreated..... %d\n", dev->nTnodesCreated);
+	buf += sprintf(buf, "nFreeTnodes........ %d\n", dev->nFreeTnodes);
+	buf += sprintf(buf, "nObjectsCreated.... %d\n", dev->nObjectsCreated);
+	buf += sprintf(buf, "nFreeObjects....... %d\n", dev->nFreeObjects);
+	buf += sprintf(buf, "nFreeChunks........ %d\n", dev->nFreeChunks);
+	buf += sprintf(buf, "\n");
+	buf += sprintf(buf, "nPageWrites........ %u\n", dev->nPageWrites);
+	buf += sprintf(buf, "nPageReads......... %u\n", dev->nPageReads);
+	buf += sprintf(buf, "nBlockErasures..... %u\n", dev->nBlockErasures);
+	buf += sprintf(buf, "nGCCopies.......... %u\n", dev->nGCCopies);
+	buf += sprintf(buf, "allGCs............. %u\n", dev->allGCs);
+	buf += sprintf(buf, "passiveGCs......... %u\n", dev->passiveGCs);
+	buf += sprintf(buf, "oldestDirtyGCs..... %u\n", dev->oldestDirtyGCs);
+	buf += sprintf(buf, "backgroundGCs...... %u\n", dev->backgroundGCs);
+	buf += sprintf(buf, "nRetriedWrites..... %u\n", dev->nRetriedWrites);
+	buf += sprintf(buf, "nRetireBlocks...... %u\n", dev->nRetiredBlocks);
+	buf += sprintf(buf, "eccFixed........... %u\n", dev->eccFixed);
+	buf += sprintf(buf, "eccUnfixed......... %u\n", dev->eccUnfixed);
+	buf += sprintf(buf, "tagsEccFixed....... %u\n", dev->tagsEccFixed);
+	buf += sprintf(buf, "tagsEccUnfixed..... %u\n", dev->tagsEccUnfixed);
+	buf += sprintf(buf, "cacheHits.......... %u\n", dev->cacheHits);
+	buf += sprintf(buf, "nDeletedFiles...... %u\n", dev->nDeletedFiles);
+	buf += sprintf(buf, "nUnlinkedFiles..... %u\n", dev->nUnlinkedFiles);
+	buf += sprintf(buf, "refreshCount....... %u\n", dev->refreshCount);
+	buf +=
+	    sprintf(buf, "nBackgroudDeletions %u\n", dev->nBackgroundDeletions);
+
+	return buf;
+}
+
+static int yaffs_proc_read(char *page,
+			   char **start,
+			   off_t offset, int count, int *eof, void *data)
+{
+	struct ylist_head *item;
+	char *buf = page;
+	int step = offset;
+	int n = 0;
+
+	/* Get proc_file_read() to step 'offset' by one on each sucessive call.
+	 * We use 'offset' (*ppos) to indicate where we are in devList.
+	 * This also assumes the user has posted a read buffer large
+	 * enough to hold the complete output; but that's life in /proc.
+	 */
+
+	*(int *)start = 1;
+
+	/* Print header first */
+	if (step == 0)
+		buf += sprintf(buf, "YAFFS built:" __DATE__ " " __TIME__"\n");
+	else if (step == 1)
+		buf += sprintf(buf,"\n");
+	else {
+		step-=2;
+		
+		down(&yaffs_context_lock);
+
+		/* Locate and print the Nth entry.  Order N-squared but N is small. */
+		ylist_for_each(item, &yaffs_context_list) {
+			struct yaffs_LinuxContext *dc = ylist_entry(item, struct yaffs_LinuxContext, contextList);
+			yaffs_Device *dev = dc->dev;
+
+			if (n < (step & ~1)) {
+				n+=2;
+				continue;
+			}
+			if((step & 1)==0){
+				buf += sprintf(buf, "\nDevice %d \"%s\"\n", n, dev->param.name);
+				buf = yaffs_dump_dev_part0(buf, dev);
+			} else
+				buf = yaffs_dump_dev_part1(buf, dev);
+			
+			break;
+		}
+		up(&yaffs_context_lock);
+	}
+
+	return buf - page < count ? buf - page : count;
+}
+
+static int yaffs_stats_proc_read(char *page,
+				char **start,
+				off_t offset, int count, int *eof, void *data)
+{
+	struct ylist_head *item;
+	char *buf = page;
+	int n = 0;
+
+	down(&yaffs_context_lock);
+
+	/* Locate and print the Nth entry.  Order N-squared but N is small. */
+	ylist_for_each(item, &yaffs_context_list) {
+		struct yaffs_LinuxContext *dc = ylist_entry(item, struct yaffs_LinuxContext, contextList);
+		yaffs_Device *dev = dc->dev;
+
+		int erasedChunks;
+		int nObjects;
+		int nTnodes;
+
+		erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+		nObjects = dev->nObjectsCreated -dev->nFreeObjects;
+		nTnodes = dev->nTnodesCreated - dev->nFreeTnodes;
+		
+		
+		buf += sprintf(buf,"%d, %d, %d, %u, %u, %d, %d\n",
+				n, dev->nFreeChunks, erasedChunks,
+				dev->backgroundGCs, dev->oldestDirtyGCs,
+				nObjects, nTnodes);
+	}
+	up(&yaffs_context_lock);
+
+
+	return buf - page < count ? buf - page : count;
+}
+
+/**
+ * Set the verbosity of the warnings and error messages.
+ *
+ * Note that the names can only be a..z or _ with the current code.
+ */
+
+static struct {
+	char *mask_name;
+	unsigned mask_bitfield;
+} mask_flags[] = {
+	{"allocate", YAFFS_TRACE_ALLOCATE},
+	{"always", YAFFS_TRACE_ALWAYS},
+	{"background", YAFFS_TRACE_BACKGROUND},
+	{"bad_blocks", YAFFS_TRACE_BAD_BLOCKS},
+	{"buffers", YAFFS_TRACE_BUFFERS},
+	{"bug", YAFFS_TRACE_BUG},
+	{"checkpt", YAFFS_TRACE_CHECKPOINT},
+	{"deletion", YAFFS_TRACE_DELETION},
+	{"erase", YAFFS_TRACE_ERASE},
+	{"error", YAFFS_TRACE_ERROR},
+	{"gc_detail", YAFFS_TRACE_GC_DETAIL},
+	{"gc", YAFFS_TRACE_GC},
+	{"lock", YAFFS_TRACE_LOCK},
+	{"mtd", YAFFS_TRACE_MTD},
+	{"nandaccess", YAFFS_TRACE_NANDACCESS},
+	{"os", YAFFS_TRACE_OS},
+	{"scan_debug", YAFFS_TRACE_SCAN_DEBUG},
+	{"scan", YAFFS_TRACE_SCAN},
+	{"tracing", YAFFS_TRACE_TRACING},
+	{"sync", YAFFS_TRACE_SYNC},
+	{"write", YAFFS_TRACE_WRITE},
+
+	{"verify", YAFFS_TRACE_VERIFY},
+	{"verify_nand", YAFFS_TRACE_VERIFY_NAND},
+	{"verify_full", YAFFS_TRACE_VERIFY_FULL},
+	{"verify_all", YAFFS_TRACE_VERIFY_ALL},
+
+	{"all", 0xffffffff},
+	{"none", 0},
+	{NULL, 0},
+};
+
+#define MAX_MASK_NAME_LENGTH 40
+static int yaffs_proc_write_trace_options(struct file *file, const char *buf,
+					 unsigned long count, void *data)
+{
+	unsigned rg = 0, mask_bitfield;
+	char *end;
+	char *mask_name;
+	const char *x;
+	char substring[MAX_MASK_NAME_LENGTH + 1];
+	int i;
+	int done = 0;
+	int add, len = 0;
+	int pos = 0;
+
+	rg = yaffs_traceMask;
+
+	while (!done && (pos < count)) {
+		done = 1;
+		while ((pos < count) && isspace(buf[pos]))
+			pos++;
+
+		switch (buf[pos]) {
+		case '+':
+		case '-':
+		case '=':
+			add = buf[pos];
+			pos++;
+			break;
+
+		default:
+			add = ' ';
+			break;
+		}
+		mask_name = NULL;
+
+		mask_bitfield = simple_strtoul(buf + pos, &end, 0);
+
+		if (end > buf + pos) {
+			mask_name = "numeral";
+			len = end - (buf + pos);
+			pos += len;
+			done = 0;
+		} else {
+			for (x = buf + pos, i = 0;
+			    (*x == '_' || (*x >= 'a' && *x <= 'z')) &&
+			    i < MAX_MASK_NAME_LENGTH; x++, i++, pos++)
+				substring[i] = *x;
+			substring[i] = '\0';
+
+			for (i = 0; mask_flags[i].mask_name != NULL; i++) {
+				if (strcmp(substring, mask_flags[i].mask_name) == 0) {
+					mask_name = mask_flags[i].mask_name;
+					mask_bitfield = mask_flags[i].mask_bitfield;
+					done = 0;
+					break;
+				}
+			}
+		}
+
+		if (mask_name != NULL) {
+			done = 0;
+			switch (add) {
+			case '-':
+				rg &= ~mask_bitfield;
+				break;
+			case '+':
+				rg |= mask_bitfield;
+				break;
+			case '=':
+				rg = mask_bitfield;
+				break;
+			default:
+				rg |= mask_bitfield;
+				break;
+			}
+		}
+	}
+
+	yaffs_traceMask = rg | YAFFS_TRACE_ALWAYS;
+
+	printk(KERN_DEBUG "new trace = 0x%08X\n", yaffs_traceMask);
+
+	if (rg & YAFFS_TRACE_ALWAYS) {
+		for (i = 0; mask_flags[i].mask_name != NULL; i++) {
+			char flag;
+			flag = ((rg & mask_flags[i].mask_bitfield) ==
+				mask_flags[i].mask_bitfield) ? '+' : '-';
+			printk(KERN_DEBUG "%c%s\n", flag, mask_flags[i].mask_name);
+		}
+	}
+
+	return count;
+}
+
+
+static int yaffs_proc_write(struct file *file, const char *buf,
+					 unsigned long count, void *data)
+{
+        return yaffs_proc_write_trace_options(file, buf, count, data);
+}
+
+/* Stuff to handle installation of file systems */
+struct file_system_to_install {
+	struct file_system_type *fst;
+	int installed;
+};
+
+static struct file_system_to_install fs_to_install[] = {
+	{&yaffs_fs_type, 0},
+	{&yaffs2_fs_type, 0},
+	{NULL, 0}
+};
+
+static int __init init_yaffs_fs(void)
+{
+	int error = 0;
+	struct file_system_to_install *fsinst;
+
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR("yaffs built " __DATE__ " " __TIME__ " Installing. \n")));
+
+#ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR(" \n\n\n\nYAFFS-WARNING CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED selected.\n\n\n\n")));
+#endif
+
+
+
+
+	init_MUTEX(&yaffs_context_lock);
+
+	/* Install the proc_fs entries */
+	my_proc_entry = create_proc_entry("yaffs",
+					       S_IRUGO | S_IFREG,
+					       YPROC_ROOT);
+
+	if (my_proc_entry) {
+		my_proc_entry->write_proc = yaffs_proc_write;
+		my_proc_entry->read_proc = yaffs_proc_read;
+		my_proc_entry->data = NULL;
+	} else
+		return -ENOMEM;
+
+	debug_proc_entry = create_proc_entry("yaffs_stats",
+					       S_IRUGO | S_IFREG,
+					       YPROC_ROOT);
+
+	if (debug_proc_entry) {
+		debug_proc_entry->write_proc = NULL;
+		debug_proc_entry->read_proc = yaffs_stats_proc_read;
+		debug_proc_entry->data = NULL;
+	} else
+		return -ENOMEM;
+
+	/* Now add the file system entries */
+
+	fsinst = fs_to_install;
+
+	while (fsinst->fst && !error) {
+		error = register_filesystem(fsinst->fst);
+		if (!error)
+			fsinst->installed = 1;
+		fsinst++;
+	}
+
+	/* Any errors? uninstall  */
+	if (error) {
+		fsinst = fs_to_install;
+
+		while (fsinst->fst) {
+			if (fsinst->installed) {
+				unregister_filesystem(fsinst->fst);
+				fsinst->installed = 0;
+			}
+			fsinst++;
+		}
+	}
+
+	return error;
+}
+
+static void __exit exit_yaffs_fs(void)
+{
+
+	struct file_system_to_install *fsinst;
+
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs built " __DATE__ " " __TIME__ " removing. \n")));
+
+	remove_proc_entry("yaffs", YPROC_ROOT);
+	remove_proc_entry("yaffs_stats", YPROC_ROOT);
+
+	fsinst = fs_to_install;
+
+	while (fsinst->fst) {
+		if (fsinst->installed) {
+			unregister_filesystem(fsinst->fst);
+			fsinst->installed = 0;
+		}
+		fsinst++;
+	}
+}
+
+module_init(init_yaffs_fs)
+module_exit(exit_yaffs_fs)
+
+MODULE_DESCRIPTION("YAFFS2 - a NAND specific flash file system");
+MODULE_AUTHOR("Charles Manning, Aleph One Ltd., 2002-2010");
+MODULE_LICENSE("GPL");
diff --git a/fs/yaffs2/yaffs_getblockinfo.h b/fs/yaffs2/yaffs_getblockinfo.h
new file mode 100644
index 00000000000..71fe1deea3c
--- /dev/null
+++ b/fs/yaffs2/yaffs_getblockinfo.h
@@ -0,0 +1,35 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_GETBLOCKINFO_H__
+#define __YAFFS_GETBLOCKINFO_H__
+
+#include "yaffs_guts.h"
+#include "yaffs_trace.h"
+
+/* Function to manipulate block info */
+static Y_INLINE yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blk)
+{
+	if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR
+		   ("**>> yaffs: getBlockInfo block %d is not valid" TENDSTR),
+		   blk));
+		YBUG();
+	}
+	return &dev->blockInfo[blk - dev->internalStartBlock];
+}
+
+#endif
diff --git a/fs/yaffs2/yaffs_guts.c b/fs/yaffs2/yaffs_guts.c
new file mode 100644
index 00000000000..9509dd401a3
--- /dev/null
+++ b/fs/yaffs2/yaffs_guts.c
@@ -0,0 +1,8237 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include "yportenv.h"
+#include "yaffs_trace.h"
+
+#include "yaffsinterface.h"
+#include "yaffs_guts.h"
+#include "yaffs_tagsvalidity.h"
+#include "yaffs_getblockinfo.h"
+
+#include "yaffs_tagscompat.h"
+#ifndef CONFIG_YAFFS_USE_OWN_SORT
+#include "yaffs_qsort.h"
+#endif
+#include "yaffs_nand.h"
+
+#include "yaffs_checkptrw.h"
+
+#include "yaffs_nand.h"
+#include "yaffs_packedtags2.h"
+
+
+/* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
+#define YAFFS_GC_GOOD_ENOUGH 2
+#define YAFFS_GC_PASSIVE_THRESHOLD 4
+
+#define YAFFS_SMALL_HOLE_THRESHOLD 3
+
+/*
+ * Checkpoints are really no benefit on very small partitions.
+ *
+ * To save space on small partitions don't bother with checkpoints unless
+ * the partition is at least this big.
+ */
+#define YAFFS_CHECKPOINT_MIN_BLOCKS 60
+
+#include "yaffs_ecc.h"
+
+
+/* Robustification (if it ever comes about...) */
+static void yaffs_RetireBlock(yaffs_Device *dev, int blockInNAND);
+static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND,
+		int erasedOk);
+static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
+				const __u8 *data,
+				const yaffs_ExtendedTags *tags);
+static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
+				const yaffs_ExtendedTags *tags);
+
+/* Other local prototypes */
+static void yaffs_UpdateParent(yaffs_Object *obj);
+static int yaffs_UnlinkObject(yaffs_Object *obj);
+static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj);
+
+static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList);
+
+static int yaffs_WriteNewChunkWithTagsToNAND(yaffs_Device *dev,
+					const __u8 *buffer,
+					yaffs_ExtendedTags *tags,
+					int useReserve);
+static int yaffs_PutChunkIntoFile(yaffs_Object *in, int chunkInInode,
+				int chunkInNAND, int inScan);
+
+static yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev, int number,
+					yaffs_ObjectType type);
+static void yaffs_AddObjectToDirectory(yaffs_Object *directory,
+				yaffs_Object *obj);
+static int yaffs_UpdateObjectHeader(yaffs_Object *in, const YCHAR *name,
+				int force, int isShrink, int shadows);
+static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj);
+static int yaffs_CheckStructures(void);
+static int yaffs_DoGenericObjectDeletion(yaffs_Object *in);
+
+static yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device *dev, int blockNo);
+
+
+static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
+				int chunkInNAND);
+
+static int yaffs_UnlinkWorker(yaffs_Object *obj);
+
+static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId,
+			int chunkInObject);
+
+static int yaffs_AllocateChunk(yaffs_Device *dev, int useReserve,
+				yaffs_BlockInfo **blockUsedPtr);
+
+static void yaffs_VerifyFreeChunks(yaffs_Device *dev);
+
+static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in);
+
+static void yaffs_VerifyDirectory(yaffs_Object *directory);
+#ifdef YAFFS_PARANOID
+static int yaffs_CheckFileSanity(yaffs_Object *in);
+#else
+#define yaffs_CheckFileSanity(in)
+#endif
+
+static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in);
+static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId);
+
+static void yaffs_InvalidateCheckpoint(yaffs_Device *dev);
+
+static int yaffs_FindChunkInFile(yaffs_Object *in, int chunkInInode,
+				yaffs_ExtendedTags *tags);
+
+static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn,
+		unsigned pos);
+static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,
+					yaffs_FileStructure *fStruct,
+					__u32 chunkId);
+
+static int yaffs_HandleHole(yaffs_Object *obj, loff_t newSize);
+static void yaffs_SkipRestOfBlock(yaffs_Device *dev);
+static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
+					int chunkInNAND,
+					const __u8 *data,
+					yaffs_ExtendedTags *tags);
+
+/* Function to calculate chunk and offset */
+
+static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, int *chunkOut,
+		__u32 *offsetOut)
+{
+	int chunk;
+	__u32 offset;
+
+	chunk  = (__u32)(addr >> dev->chunkShift);
+
+	if (dev->chunkDiv == 1) {
+		/* easy power of 2 case */
+		offset = (__u32)(addr & dev->chunkMask);
+	} else {
+		/* Non power-of-2 case */
+
+		loff_t chunkBase;
+
+		chunk /= dev->chunkDiv;
+
+		chunkBase = ((loff_t)chunk) * dev->nDataBytesPerChunk;
+		offset = (__u32)(addr - chunkBase);
+	}
+
+	*chunkOut = chunk;
+	*offsetOut = offset;
+}
+
+/* Function to return the number of shifts for a power of 2 greater than or
+ * equal to the given number
+ * Note we don't try to cater for all possible numbers and this does not have to
+ * be hellishly efficient.
+ */
+
+static __u32 ShiftsGE(__u32 x)
+{
+	int extraBits;
+	int nShifts;
+
+	nShifts = extraBits = 0;
+
+	while (x > 1) {
+		if (x & 1)
+			extraBits++;
+		x >>= 1;
+		nShifts++;
+	}
+
+	if (extraBits)
+		nShifts++;
+
+	return nShifts;
+}
+
+/* Function to return the number of shifts to get a 1 in bit 0
+ */
+
+static __u32 Shifts(__u32 x)
+{
+	__u32 nShifts;
+
+	nShifts =  0;
+
+	if (!x)
+		return 0;
+
+	while (!(x&1)) {
+		x >>= 1;
+		nShifts++;
+	}
+
+	return nShifts;
+}
+
+
+
+/*
+ * Temporary buffer manipulations.
+ */
+
+static int yaffs_InitialiseTempBuffers(yaffs_Device *dev)
+{
+	int i;
+	__u8 *buf = (__u8 *)1;
+
+	memset(dev->tempBuffer, 0, sizeof(dev->tempBuffer));
+
+	for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
+		dev->tempBuffer[i].line = 0;	/* not in use */
+		dev->tempBuffer[i].buffer = buf =
+		    YMALLOC_DMA(dev->param.totalBytesPerChunk);
+	}
+
+	return buf ? YAFFS_OK : YAFFS_FAIL;
+}
+
+__u8 *yaffs_GetTempBuffer(yaffs_Device *dev, int lineNo)
+{
+	int i, j;
+
+	dev->tempInUse++;
+	if (dev->tempInUse > dev->maxTemp)
+		dev->maxTemp = dev->tempInUse;
+
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
+		if (dev->tempBuffer[i].line == 0) {
+			dev->tempBuffer[i].line = lineNo;
+			if ((i + 1) > dev->maxTemp) {
+				dev->maxTemp = i + 1;
+				for (j = 0; j <= i; j++)
+					dev->tempBuffer[j].maxLine =
+					    dev->tempBuffer[j].line;
+			}
+
+			return dev->tempBuffer[i].buffer;
+		}
+	}
+
+	T(YAFFS_TRACE_BUFFERS,
+	  (TSTR("Out of temp buffers at line %d, other held by lines:"),
+	   lineNo));
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
+		T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->tempBuffer[i].line));
+
+	T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
+
+	/*
+	 * If we got here then we have to allocate an unmanaged one
+	 * This is not good.
+	 */
+
+	dev->unmanagedTempAllocations++;
+	return YMALLOC(dev->nDataBytesPerChunk);
+
+}
+
+void yaffs_ReleaseTempBuffer(yaffs_Device *dev, __u8 *buffer,
+				    int lineNo)
+{
+	int i;
+
+	dev->tempInUse--;
+
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
+		if (dev->tempBuffer[i].buffer == buffer) {
+			dev->tempBuffer[i].line = 0;
+			return;
+		}
+	}
+
+	if (buffer) {
+		/* assume it is an unmanaged one. */
+		T(YAFFS_TRACE_BUFFERS,
+		  (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
+		   lineNo));
+		YFREE(buffer);
+		dev->unmanagedTempDeallocations++;
+	}
+
+}
+
+/*
+ * Determine if we have a managed buffer.
+ */
+int yaffs_IsManagedTempBuffer(yaffs_Device *dev, const __u8 *buffer)
+{
+	int i;
+
+	for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
+		if (dev->tempBuffer[i].buffer == buffer)
+			return 1;
+	}
+
+	for (i = 0; i < dev->param.nShortOpCaches; i++) {
+		if (dev->srCache[i].data == buffer)
+			return 1;
+	}
+
+	if (buffer == dev->checkpointBuffer)
+		return 1;
+
+	T(YAFFS_TRACE_ALWAYS,
+		(TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
+	return 0;
+}
+
+
+
+/*
+ * Chunk bitmap manipulations
+ */
+
+static Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device *dev, int blk)
+{
+	if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
+			blk));
+		YBUG();
+	}
+	return dev->chunkBits +
+		(dev->chunkBitmapStride * (blk - dev->internalStartBlock));
+}
+
+static Y_INLINE void yaffs_VerifyChunkBitId(yaffs_Device *dev, int blk, int chunk)
+{
+	if (blk < dev->internalStartBlock || blk > dev->internalEndBlock ||
+			chunk < 0 || chunk >= dev->param.nChunksPerBlock) {
+		T(YAFFS_TRACE_ERROR,
+		(TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),
+			blk, chunk));
+		YBUG();
+	}
+}
+
+static Y_INLINE void yaffs_ClearChunkBits(yaffs_Device *dev, int blk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+
+	memset(blkBits, 0, dev->chunkBitmapStride);
+}
+
+static Y_INLINE void yaffs_ClearChunkBit(yaffs_Device *dev, int blk, int chunk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+
+	yaffs_VerifyChunkBitId(dev, blk, chunk);
+
+	blkBits[chunk / 8] &= ~(1 << (chunk & 7));
+}
+
+static Y_INLINE void yaffs_SetChunkBit(yaffs_Device *dev, int blk, int chunk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+
+	yaffs_VerifyChunkBitId(dev, blk, chunk);
+
+	blkBits[chunk / 8] |= (1 << (chunk & 7));
+}
+
+static Y_INLINE int yaffs_CheckChunkBit(yaffs_Device *dev, int blk, int chunk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+	yaffs_VerifyChunkBitId(dev, blk, chunk);
+
+	return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
+}
+
+static Y_INLINE int yaffs_StillSomeChunkBits(yaffs_Device *dev, int blk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+	int i;
+	for (i = 0; i < dev->chunkBitmapStride; i++) {
+		if (*blkBits)
+			return 1;
+		blkBits++;
+	}
+	return 0;
+}
+
+static int yaffs_CountChunkBits(yaffs_Device *dev, int blk)
+{
+	__u8 *blkBits = yaffs_BlockBits(dev, blk);
+	int i;
+	int n = 0;
+	for (i = 0; i < dev->chunkBitmapStride; i++) {
+		__u8 x = *blkBits;
+		while (x) {
+			if (x & 1)
+				n++;
+			x >>= 1;
+		}
+
+		blkBits++;
+	}
+	return n;
+}
+
+/*
+ * Verification code
+ */
+
+static int yaffs_SkipVerification(yaffs_Device *dev)
+{
+	dev=dev;
+	return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY | YAFFS_TRACE_VERIFY_FULL));
+}
+
+static int yaffs_SkipFullVerification(yaffs_Device *dev)
+{
+	dev=dev;
+	return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_FULL));
+}
+
+static int yaffs_SkipNANDVerification(yaffs_Device *dev)
+{
+	dev=dev;
+	return !(yaffs_traceMask & (YAFFS_TRACE_VERIFY_NAND));
+}
+
+static const char *blockStateName[] = {
+"Unknown",
+"Needs scanning",
+"Scanning",
+"Empty",
+"Allocating",
+"Full",
+"Dirty",
+"Checkpoint",
+"Collecting",
+"Dead"
+};
+
+static void yaffs_VerifyBlock(yaffs_Device *dev, yaffs_BlockInfo *bi, int n)
+{
+	int actuallyUsed;
+	int inUse;
+
+	if (yaffs_SkipVerification(dev))
+		return;
+
+	/* Report illegal runtime states */
+	if (bi->blockState >= YAFFS_NUMBER_OF_BLOCK_STATES)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has undefined state %d"TENDSTR), n, bi->blockState));
+
+	switch (bi->blockState) {
+	case YAFFS_BLOCK_STATE_UNKNOWN:
+	case YAFFS_BLOCK_STATE_SCANNING:
+	case YAFFS_BLOCK_STATE_NEEDS_SCANNING:
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has bad run-state %s"TENDSTR),
+		n, blockStateName[bi->blockState]));
+	}
+
+	/* Check pages in use and soft deletions are legal */
+
+	actuallyUsed = bi->pagesInUse - bi->softDeletions;
+
+	if (bi->pagesInUse < 0 || bi->pagesInUse > dev->param.nChunksPerBlock ||
+	   bi->softDeletions < 0 || bi->softDeletions > dev->param.nChunksPerBlock ||
+	   actuallyUsed < 0 || actuallyUsed > dev->param.nChunksPerBlock)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has illegal values pagesInUsed %d softDeletions %d"TENDSTR),
+		n, bi->pagesInUse, bi->softDeletions));
+
+
+	/* Check chunk bitmap legal */
+	inUse = yaffs_CountChunkBits(dev, n);
+	if (inUse != bi->pagesInUse)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has inconsistent values pagesInUse %d counted chunk bits %d"TENDSTR),
+			n, bi->pagesInUse, inUse));
+
+	/* Check that the sequence number is valid.
+	 * Ten million is legal, but is very unlikely
+	 */
+	if (dev->param.isYaffs2 &&
+	   (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING || bi->blockState == YAFFS_BLOCK_STATE_FULL) &&
+	   (bi->sequenceNumber < YAFFS_LOWEST_SEQUENCE_NUMBER || bi->sequenceNumber > 10000000))
+		T(YAFFS_TRACE_VERIFY, (TSTR("Block %d has suspect sequence number of %d"TENDSTR),
+		n, bi->sequenceNumber));
+}
+
+static void yaffs_VerifyCollectedBlock(yaffs_Device *dev, yaffs_BlockInfo *bi,
+		int n)
+{
+	yaffs_VerifyBlock(dev, bi, n);
+
+	/* After collection the block should be in the erased state */
+	/* This will need to change if we do partial gc */
+
+	if (bi->blockState != YAFFS_BLOCK_STATE_COLLECTING &&
+			bi->blockState != YAFFS_BLOCK_STATE_EMPTY) {
+		T(YAFFS_TRACE_ERROR, (TSTR("Block %d is in state %d after gc, should be erased"TENDSTR),
+			n, bi->blockState));
+	}
+}
+
+static void yaffs_VerifyBlocks(yaffs_Device *dev)
+{
+	int i;
+	int nBlocksPerState[YAFFS_NUMBER_OF_BLOCK_STATES];
+	int nIllegalBlockStates = 0;
+
+	if (yaffs_SkipVerification(dev))
+		return;
+
+	memset(nBlocksPerState, 0, sizeof(nBlocksPerState));
+
+	for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
+		yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, i);
+		yaffs_VerifyBlock(dev, bi, i);
+
+		if (bi->blockState < YAFFS_NUMBER_OF_BLOCK_STATES)
+			nBlocksPerState[bi->blockState]++;
+		else
+			nIllegalBlockStates++;
+	}
+
+	T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));
+	T(YAFFS_TRACE_VERIFY, (TSTR("Block summary"TENDSTR)));
+
+	T(YAFFS_TRACE_VERIFY, (TSTR("%d blocks have illegal states"TENDSTR), nIllegalBlockStates));
+	if (nBlocksPerState[YAFFS_BLOCK_STATE_ALLOCATING] > 1)
+		T(YAFFS_TRACE_VERIFY, (TSTR("Too many allocating blocks"TENDSTR)));
+
+	for (i = 0; i < YAFFS_NUMBER_OF_BLOCK_STATES; i++)
+		T(YAFFS_TRACE_VERIFY,
+		  (TSTR("%s %d blocks"TENDSTR),
+		  blockStateName[i], nBlocksPerState[i]));
+
+	if (dev->blocksInCheckpoint != nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT])
+		T(YAFFS_TRACE_VERIFY,
+		 (TSTR("Checkpoint block count wrong dev %d count %d"TENDSTR),
+		 dev->blocksInCheckpoint, nBlocksPerState[YAFFS_BLOCK_STATE_CHECKPOINT]));
+
+	if (dev->nErasedBlocks != nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY])
+		T(YAFFS_TRACE_VERIFY,
+		 (TSTR("Erased block count wrong dev %d count %d"TENDSTR),
+		 dev->nErasedBlocks, nBlocksPerState[YAFFS_BLOCK_STATE_EMPTY]));
+
+	if (nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING] > 1)
+		T(YAFFS_TRACE_VERIFY,
+		 (TSTR("Too many collecting blocks %d (max is 1)"TENDSTR),
+		 nBlocksPerState[YAFFS_BLOCK_STATE_COLLECTING]));
+
+	T(YAFFS_TRACE_VERIFY, (TSTR(""TENDSTR)));
+
+}
+
+/*
+ * Verify the object header. oh must be valid, but obj and tags may be NULL in which
+ * case those tests will not be performed.
+ */
+static void yaffs_VerifyObjectHeader(yaffs_Object *obj, yaffs_ObjectHeader *oh, yaffs_ExtendedTags *tags, int parentCheck)
+{
+	if (obj && yaffs_SkipVerification(obj->myDev))
+		return;
+
+	if (!(tags && obj && oh)) {
+		T(YAFFS_TRACE_VERIFY,
+				(TSTR("Verifying object header tags %p obj %p oh %p"TENDSTR),
+				tags, obj, oh));
+		return;
+	}
+
+	if (oh->type <= YAFFS_OBJECT_TYPE_UNKNOWN ||
+			oh->type > YAFFS_OBJECT_TYPE_MAX)
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header type is illegal value 0x%x"TENDSTR),
+			tags->objectId, oh->type));
+
+	if (tags->objectId != obj->objectId)
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header mismatch objectId %d"TENDSTR),
+			tags->objectId, obj->objectId));
+
+
+	/*
+	 * Check that the object's parent ids match if parentCheck requested.
+	 *
+	 * Tests do not apply to the root object.
+	 */
+
+	if (parentCheck && tags->objectId > 1 && !obj->parent)
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header mismatch parentId %d obj->parent is NULL"TENDSTR),
+			tags->objectId, oh->parentObjectId));
+
+	if (parentCheck && obj->parent &&
+			oh->parentObjectId != obj->parent->objectId &&
+			(oh->parentObjectId != YAFFS_OBJECTID_UNLINKED ||
+			obj->parent->objectId != YAFFS_OBJECTID_DELETED))
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header mismatch parentId %d parentObjectId %d"TENDSTR),
+			tags->objectId, oh->parentObjectId, obj->parent->objectId));
+
+	if (tags->objectId > 1 && oh->name[0] == 0) /* Null name */
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header name is NULL"TENDSTR),
+			obj->objectId));
+
+	if (tags->objectId > 1 && ((__u8)(oh->name[0])) == 0xff) /* Trashed name */
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d header name is 0xFF"TENDSTR),
+			obj->objectId));
+}
+
+
+#if 0
+/* Not being used, but don't want to throw away yet */
+static int yaffs_VerifyTnodeWorker(yaffs_Object *obj, yaffs_Tnode *tn,
+					__u32 level, int chunkOffset)
+{
+	int i;
+	yaffs_Device *dev = obj->myDev;
+	int ok = 1;
+
+	if (tn) {
+		if (level > 0) {
+
+			for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
+				if (tn->internal[i]) {
+					ok = yaffs_VerifyTnodeWorker(obj,
+							tn->internal[i],
+							level - 1,
+							(chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
+				}
+			}
+		} else if (level == 0) {
+			yaffs_ExtendedTags tags;
+			__u32 objectId = obj->objectId;
+
+			chunkOffset <<=  YAFFS_TNODES_LEVEL0_BITS;
+
+			for (i = 0; i < YAFFS_NTNODES_LEVEL0; i++) {
+				__u32 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
+
+				if (theChunk > 0) {
+					/* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),tags.objectId,tags.chunkId,theChunk)); */
+					yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL, &tags);
+					if (tags.objectId != objectId || tags.chunkId != chunkOffset) {
+						T(~0, (TSTR("Object %d chunkId %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
+							objectId, chunkOffset, theChunk,
+							tags.objectId, tags.chunkId));
+					}
+				}
+				chunkOffset++;
+			}
+		}
+	}
+
+	return ok;
+
+}
+
+#endif
+
+static void yaffs_VerifyFile(yaffs_Object *obj)
+{
+	int requiredTallness;
+	int actualTallness;
+	__u32 lastChunk;
+	__u32 x;
+	__u32 i;
+	yaffs_Device *dev;
+	yaffs_ExtendedTags tags;
+	yaffs_Tnode *tn;
+	__u32 objectId;
+
+	if (!obj)
+		return;
+
+	if (yaffs_SkipVerification(obj->myDev))
+		return;
+
+	dev = obj->myDev;
+	objectId = obj->objectId;
+
+	/* Check file size is consistent with tnode depth */
+	lastChunk =  obj->variant.fileVariant.fileSize / dev->nDataBytesPerChunk + 1;
+	x = lastChunk >> YAFFS_TNODES_LEVEL0_BITS;
+	requiredTallness = 0;
+	while (x > 0) {
+		x >>= YAFFS_TNODES_INTERNAL_BITS;
+		requiredTallness++;
+	}
+
+	actualTallness = obj->variant.fileVariant.topLevel;
+
+	/* Check that the chunks in the tnode tree are all correct.
+	 * We do this by scanning through the tnode tree and
+	 * checking the tags for every chunk match.
+	 */
+
+	if (yaffs_SkipNANDVerification(dev))
+		return;
+
+	for (i = 1; i <= lastChunk; i++) {
+		tn = yaffs_FindLevel0Tnode(dev, &obj->variant.fileVariant, i);
+
+		if (tn) {
+			__u32 theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
+			if (theChunk > 0) {
+				/* T(~0,(TSTR("verifying (%d:%d) %d"TENDSTR),objectId,i,theChunk)); */
+				yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL, &tags);
+				if (tags.objectId != objectId || tags.chunkId != i) {
+					T(~0, (TSTR("Object %d chunkId %d NAND mismatch chunk %d tags (%d:%d)"TENDSTR),
+						objectId, i, theChunk,
+						tags.objectId, tags.chunkId));
+				}
+			}
+		}
+	}
+}
+
+
+static void yaffs_VerifyHardLink(yaffs_Object *obj)
+{
+	if (obj && yaffs_SkipVerification(obj->myDev))
+		return;
+
+	/* Verify sane equivalent object */
+}
+
+static void yaffs_VerifySymlink(yaffs_Object *obj)
+{
+	if (obj && yaffs_SkipVerification(obj->myDev))
+		return;
+
+	/* Verify symlink string */
+}
+
+static void yaffs_VerifySpecial(yaffs_Object *obj)
+{
+	if (obj && yaffs_SkipVerification(obj->myDev))
+		return;
+}
+
+static void yaffs_VerifyObject(yaffs_Object *obj)
+{
+	yaffs_Device *dev;
+
+	__u32 chunkMin;
+	__u32 chunkMax;
+
+	__u32 chunkIdOk;
+	__u32 chunkInRange;
+	__u32 chunkShouldNotBeDeleted;
+	__u32 chunkValid;
+
+	if (!obj)
+		return;
+
+	if (obj->beingCreated)
+		return;
+
+	dev = obj->myDev;
+
+	if (yaffs_SkipVerification(dev))
+		return;
+
+	/* Check sane object header chunk */
+
+	chunkMin = dev->internalStartBlock * dev->param.nChunksPerBlock;
+	chunkMax = (dev->internalEndBlock+1) * dev->param.nChunksPerBlock - 1;
+
+	chunkInRange = (((unsigned)(obj->hdrChunk)) >= chunkMin && ((unsigned)(obj->hdrChunk)) <= chunkMax);
+	chunkIdOk = chunkInRange || (obj->hdrChunk == 0);
+	chunkValid = chunkInRange &&
+			yaffs_CheckChunkBit(dev,
+					obj->hdrChunk / dev->param.nChunksPerBlock,
+					obj->hdrChunk % dev->param.nChunksPerBlock);
+	chunkShouldNotBeDeleted = chunkInRange && !chunkValid;
+
+	if (!obj->fake &&
+			(!chunkIdOk || chunkShouldNotBeDeleted)) {
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d has chunkId %d %s %s"TENDSTR),
+			obj->objectId, obj->hdrChunk,
+			chunkIdOk ? "" : ",out of range",
+			chunkShouldNotBeDeleted ? ",marked as deleted" : ""));
+	}
+
+	if (chunkValid && !yaffs_SkipNANDVerification(dev)) {
+		yaffs_ExtendedTags tags;
+		yaffs_ObjectHeader *oh;
+		__u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
+
+		oh = (yaffs_ObjectHeader *)buffer;
+
+		yaffs_ReadChunkWithTagsFromNAND(dev, obj->hdrChunk, buffer,
+				&tags);
+
+		yaffs_VerifyObjectHeader(obj, oh, &tags, 1);
+
+		yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+	}
+
+	/* Verify it has a parent */
+	if (obj && !obj->fake &&
+			(!obj->parent || obj->parent->myDev != dev)) {
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d has parent pointer %p which does not look like an object"TENDSTR),
+			obj->objectId, obj->parent));
+	}
+
+	/* Verify parent is a directory */
+	if (obj->parent && obj->parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Obj %d's parent is not a directory (type %d)"TENDSTR),
+			obj->objectId, obj->parent->variantType));
+	}
+
+	switch (obj->variantType) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		yaffs_VerifyFile(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		yaffs_VerifySymlink(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_DIRECTORY:
+		yaffs_VerifyDirectory(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_HARDLINK:
+		yaffs_VerifyHardLink(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SPECIAL:
+		yaffs_VerifySpecial(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_UNKNOWN:
+	default:
+		T(YAFFS_TRACE_VERIFY,
+		(TSTR("Obj %d has illegaltype %d"TENDSTR),
+		obj->objectId, obj->variantType));
+		break;
+	}
+}
+
+static void yaffs_VerifyObjects(yaffs_Device *dev)
+{
+	yaffs_Object *obj;
+	int i;
+	struct ylist_head *lh;
+
+	if (yaffs_SkipVerification(dev))
+		return;
+
+	/* Iterate through the objects in each hash entry */
+
+	for (i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++) {
+		ylist_for_each(lh, &dev->objectBucket[i].list) {
+			if (lh) {
+				obj = ylist_entry(lh, yaffs_Object, hashLink);
+				yaffs_VerifyObject(obj);
+			}
+		}
+	}
+}
+
+
+/*
+ *  Simple hash function. Needs to have a reasonable spread
+ */
+
+static Y_INLINE int yaffs_HashFunction(int n)
+{
+	n = abs(n);
+	return n % YAFFS_NOBJECT_BUCKETS;
+}
+
+/*
+ * Access functions to useful fake objects.
+ * Note that root might have a presence in NAND if permissions are set.
+ */
+
+yaffs_Object *yaffs_Root(yaffs_Device *dev)
+{
+	return dev->rootDir;
+}
+
+yaffs_Object *yaffs_LostNFound(yaffs_Device *dev)
+{
+	return dev->lostNFoundDir;
+}
+
+
+/*
+ *  Erased NAND checking functions
+ */
+
+int yaffs_CheckFF(__u8 *buffer, int nBytes)
+{
+	/* Horrible, slow implementation */
+	while (nBytes--) {
+		if (*buffer != 0xFF)
+			return 0;
+		buffer++;
+	}
+	return 1;
+}
+
+static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
+				int chunkInNAND)
+{
+	int retval = YAFFS_OK;
+	__u8 *data = yaffs_GetTempBuffer(dev, __LINE__);
+	yaffs_ExtendedTags tags;
+	int result;
+
+	result = yaffs_ReadChunkWithTagsFromNAND(dev, chunkInNAND, data, &tags);
+
+	if (tags.eccResult > YAFFS_ECC_RESULT_NO_ERROR)
+		retval = YAFFS_FAIL;
+
+	if (!yaffs_CheckFF(data, dev->nDataBytesPerChunk) || tags.chunkUsed) {
+		T(YAFFS_TRACE_NANDACCESS,
+		  (TSTR("Chunk %d not erased" TENDSTR), chunkInNAND));
+		retval = YAFFS_FAIL;
+	}
+
+	yaffs_ReleaseTempBuffer(dev, data, __LINE__);
+
+	return retval;
+
+}
+
+
+static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
+					int chunkInNAND,
+					const __u8 *data,
+					yaffs_ExtendedTags *tags)
+{
+	int retval = YAFFS_OK;
+	yaffs_ExtendedTags tempTags;
+	__u8 *buffer = yaffs_GetTempBuffer(dev,__LINE__);
+	int result;
+	
+	result = yaffs_ReadChunkWithTagsFromNAND(dev,chunkInNAND,buffer,&tempTags);
+	if(memcmp(buffer,data,dev->nDataBytesPerChunk) ||
+		tempTags.objectId != tags->objectId ||
+		tempTags.chunkId  != tags->chunkId ||
+		tempTags.byteCount != tags->byteCount)
+		retval = YAFFS_FAIL;
+
+	yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+
+	return retval;
+}
+
+static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
+					const __u8 *data,
+					yaffs_ExtendedTags *tags,
+					int useReserve)
+{
+	int attempts = 0;
+	int writeOk = 0;
+	int chunk;
+
+	yaffs_InvalidateCheckpoint(dev);
+
+	do {
+		yaffs_BlockInfo *bi = 0;
+		int erasedOk = 0;
+
+		chunk = yaffs_AllocateChunk(dev, useReserve, &bi);
+		if (chunk < 0) {
+			/* no space */
+			break;
+		}
+
+		/* First check this chunk is erased, if it needs
+		 * checking.  The checking policy (unless forced
+		 * always on) is as follows:
+		 *
+		 * Check the first page we try to write in a block.
+		 * If the check passes then we don't need to check any
+		 * more.	If the check fails, we check again...
+		 * If the block has been erased, we don't need to check.
+		 *
+		 * However, if the block has been prioritised for gc,
+		 * then we think there might be something odd about
+		 * this block and stop using it.
+		 *
+		 * Rationale: We should only ever see chunks that have
+		 * not been erased if there was a partially written
+		 * chunk due to power loss.  This checking policy should
+		 * catch that case with very few checks and thus save a
+		 * lot of checks that are most likely not needed.
+		 *
+		 * Mods to the above
+		 * If an erase check fails or the write fails we skip the 
+		 * rest of the block.
+		 */
+
+		/* let's give it a try */
+		attempts++;
+
+#ifdef CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED
+		bi->skipErasedCheck = 0;
+#endif
+		if (!bi->skipErasedCheck) {
+			erasedOk = yaffs_CheckChunkErased(dev, chunk);
+			if (erasedOk != YAFFS_OK) {
+				T(YAFFS_TRACE_ERROR,
+				(TSTR("**>> yaffs chunk %d was not erased"
+				TENDSTR), chunk));
+
+				/* If not erased, delete this one,
+				 * skip rest of block and
+				 * try another chunk */
+				 yaffs_DeleteChunk(dev,chunk,1,__LINE__);
+				 yaffs_SkipRestOfBlock(dev);
+				continue;
+			}
+		}
+
+		writeOk = yaffs_WriteChunkWithTagsToNAND(dev, chunk,
+				data, tags);
+
+		if(!bi->skipErasedCheck)
+			writeOk = yaffs_VerifyChunkWritten(dev, chunk, data, tags);
+
+		if (writeOk != YAFFS_OK) {
+			/* Clean up aborted write, skip to next block and
+			 * try another chunk */
+			yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
+			continue;
+		}
+
+		bi->skipErasedCheck = 1;
+
+		/* Copy the data into the robustification buffer */
+		yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
+
+	} while (writeOk != YAFFS_OK &&
+		(yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
+
+	if (!writeOk)
+		chunk = -1;
+
+	if (attempts > 1) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("**>> yaffs write required %d attempts" TENDSTR),
+			attempts));
+
+		dev->nRetriedWrites += (attempts - 1);
+	}
+
+	return chunk;
+}
+
+
+/*
+ * Oldest Dirty Sequence Number handling.
+ */
+ 
+/* yaffs_CalcOldestDirtySequence()
+ * yaffs_FindOldestDirtySequence()
+ * Calculate the oldest dirty sequence number if we don't know it.
+ */
+static void yaffs_CalcOldestDirtySequence(yaffs_Device *dev)
+{
+	int i;
+	unsigned seq;
+	unsigned blockNo = 0;
+	yaffs_BlockInfo *b;
+
+	if(!dev->param.isYaffs2)
+		return;
+
+	/* Find the oldest dirty sequence number. */
+	seq = dev->sequenceNumber + 1;
+	b = dev->blockInfo;
+	for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
+		if (b->blockState == YAFFS_BLOCK_STATE_FULL &&
+			(b->pagesInUse - b->softDeletions) < dev->param.nChunksPerBlock &&
+			b->sequenceNumber < seq) {
+			seq = b->sequenceNumber;
+			blockNo = i;
+		}
+		b++;
+	}
+
+	if(blockNo){
+		dev->oldestDirtySequence = seq;
+		dev->oldestDirtyBlock = blockNo;
+	}
+
+}
+
+
+static void yaffs_FindOldestDirtySequence(yaffs_Device *dev)
+{
+	if(dev->param.isYaffs2 && !dev->oldestDirtySequence)
+		yaffs_CalcOldestDirtySequence(dev);
+}
+
+/*
+ * yaffs_ClearOldestDirtySequence()
+ * Called when a block is erased or marked bad. (ie. when its sequenceNumber
+ * becomes invalid). If the value matches the oldest then we clear 
+ * dev->oldestDirtySequence to force its recomputation.
+ */
+static void yaffs_ClearOldestDirtySequence(yaffs_Device *dev, yaffs_BlockInfo *bi)
+{
+
+	if(!dev->param.isYaffs2)
+		return;
+
+	if(!bi || bi->sequenceNumber == dev->oldestDirtySequence){
+		dev->oldestDirtySequence = 0;
+		dev->oldestDirtyBlock = 0;
+	}
+}
+
+/*
+ * yaffs_UpdateOldestDirtySequence()
+ * Update the oldest dirty sequence number whenever we dirty a block.
+ * Only do this if the oldestDirtySequence is actually being tracked.
+ */
+static void yaffs_UpdateOldestDirtySequence(yaffs_Device *dev, unsigned blockNo, yaffs_BlockInfo *bi)
+{
+	if(dev->param.isYaffs2 && dev->oldestDirtySequence){
+		if(dev->oldestDirtySequence > bi->sequenceNumber){
+			dev->oldestDirtySequence = bi->sequenceNumber;
+			dev->oldestDirtyBlock = blockNo;
+		}
+	}
+}
+ 
+/*
+ * Block retiring for handling a broken block.
+ */
+
+static void yaffs_RetireBlock(yaffs_Device *dev, int blockInNAND)
+{
+	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
+
+	yaffs_InvalidateCheckpoint(dev);
+	
+	yaffs_ClearOldestDirtySequence(dev,bi);
+
+	if (yaffs_MarkBlockBad(dev, blockInNAND) != YAFFS_OK) {
+		if (yaffs_EraseBlockInNAND(dev, blockInNAND) != YAFFS_OK) {
+			T(YAFFS_TRACE_ALWAYS, (TSTR(
+				"yaffs: Failed to mark bad and erase block %d"
+				TENDSTR), blockInNAND));
+		} else {
+			yaffs_ExtendedTags tags;
+			int chunkId = blockInNAND * dev->param.nChunksPerBlock;
+
+			__u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
+
+			memset(buffer, 0xff, dev->nDataBytesPerChunk);
+			yaffs_InitialiseTags(&tags);
+			tags.sequenceNumber = YAFFS_SEQUENCE_BAD_BLOCK;
+			if (dev->param.writeChunkWithTagsToNAND(dev, chunkId -
+				dev->chunkOffset, buffer, &tags) != YAFFS_OK)
+				T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Failed to "
+					TCONT("write bad block marker to block %d")
+					TENDSTR), blockInNAND));
+
+			yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+		}
+	}
+
+	bi->blockState = YAFFS_BLOCK_STATE_DEAD;
+	bi->gcPrioritise = 0;
+	bi->needsRetiring = 0;
+
+	dev->nRetiredBlocks++;
+}
+
+/*
+ * Functions for robustisizing TODO
+ *
+ */
+
+static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
+				const __u8 *data,
+				const yaffs_ExtendedTags *tags)
+{
+	dev=dev;
+	chunkInNAND=chunkInNAND;
+	data=data;
+	tags=tags;
+}
+
+static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
+				const yaffs_ExtendedTags *tags)
+{
+	dev=dev;
+	chunkInNAND=chunkInNAND;
+	tags=tags;
+}
+
+void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi)
+{
+	if (!bi->gcPrioritise) {
+		bi->gcPrioritise = 1;
+		dev->hasPendingPrioritisedGCs = 1;
+		bi->chunkErrorStrikes++;
+
+		if (bi->chunkErrorStrikes > 3) {
+			bi->needsRetiring = 1; /* Too many stikes, so retire this */
+			T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
+
+		}
+	}
+}
+
+static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND,
+		int erasedOk)
+{
+	int blockInNAND = chunkInNAND / dev->param.nChunksPerBlock;
+	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockInNAND);
+
+	yaffs_HandleChunkError(dev, bi);
+
+	if (erasedOk) {
+		/* Was an actual write failure, so mark the block for retirement  */
+		bi->needsRetiring = 1;
+		T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+		  (TSTR("**>> Block %d needs retiring" TENDSTR), blockInNAND));
+	}
+
+	/* Delete the chunk */
+	yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
+	yaffs_SkipRestOfBlock(dev);
+}
+
+
+/*---------------- Name handling functions ------------*/
+
+static __u16 yaffs_CalcNameSum(const YCHAR *name)
+{
+	__u16 sum = 0;
+	__u16 i = 1;
+
+	const YUCHAR *bname = (const YUCHAR *) name;
+	if (bname) {
+		while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
+
+#ifdef CONFIG_YAFFS_CASE_INSENSITIVE
+			sum += yaffs_toupper(*bname) * i;
+#else
+			sum += (*bname) * i;
+#endif
+			i++;
+			bname++;
+		}
+	}
+	return sum;
+}
+
+static void yaffs_SetObjectName(yaffs_Object *obj, const YCHAR *name)
+{
+#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+	memset(obj->shortName, 0, sizeof(YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1));
+	if (name && yaffs_strnlen(name,YAFFS_SHORT_NAME_LENGTH+1) <= YAFFS_SHORT_NAME_LENGTH)
+		yaffs_strcpy(obj->shortName, name);
+	else
+		obj->shortName[0] = _Y('\0');
+#endif
+	obj->sum = yaffs_CalcNameSum(name);
+}
+
+/*-------------------- TNODES -------------------
+
+ * List of spare tnodes
+ * The list is hooked together using the first pointer
+ * in the tnode.
+ */
+
+/* yaffs_CreateTnodes creates a bunch more tnodes and
+ * adds them to the tnode free list.
+ * Don't use this function directly
+ */
+static Y_INLINE int yaffs_CalcTnodeSize(yaffs_Device *dev)
+{
+	int tnodeSize;
+	/* Calculate the tnode size in bytes for variable width tnode support.
+	 * Must be a multiple of 32-bits  */
+	tnodeSize = (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8;
+
+	if (tnodeSize < sizeof(yaffs_Tnode))
+		tnodeSize = sizeof(yaffs_Tnode);
+	return tnodeSize;
+}
+
+static int yaffs_CreateTnodes(yaffs_Device *dev, int nTnodes)
+{
+	int i;
+	int tnodeSize = yaffs_CalcTnodeSize(dev);
+	yaffs_Tnode *newTnodes;
+	__u8 *mem;
+	yaffs_Tnode *curr;
+	yaffs_Tnode *next;
+	yaffs_TnodeList *tnl;
+
+	if (nTnodes < 1)
+		return YAFFS_OK;
+
+
+	/* make these things */
+
+	newTnodes = YMALLOC(nTnodes * tnodeSize);
+	mem = (__u8 *)newTnodes;
+
+	if (!newTnodes) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("yaffs: Could not allocate Tnodes" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* Hook them into the free list */
+#if 0
+	for (i = 0; i < nTnodes - 1; i++) {
+		newTnodes[i].internal[0] = &newTnodes[i + 1];
+#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
+		newTnodes[i].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
+#endif
+	}
+
+	newTnodes[nTnodes - 1].internal[0] = dev->freeTnodes;
+#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
+	newTnodes[nTnodes - 1].internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
+#endif
+	dev->freeTnodes = newTnodes;
+#else
+	/* New hookup for wide tnodes */
+	for (i = 0; i < nTnodes - 1; i++) {
+		curr = (yaffs_Tnode *) &mem[i * tnodeSize];
+		next = (yaffs_Tnode *) &mem[(i+1) * tnodeSize];
+		curr->internal[0] = next;
+	}
+
+	curr = (yaffs_Tnode *) &mem[(nTnodes - 1) * tnodeSize];
+	curr->internal[0] = dev->freeTnodes;
+	dev->freeTnodes = (yaffs_Tnode *)mem;
+
+#endif
+
+
+	dev->nFreeTnodes += nTnodes;
+	dev->nTnodesCreated += nTnodes;
+
+	/* Now add this bunch of tnodes to a list for freeing up.
+	 * NB If we can't add this to the management list it isn't fatal
+	 * but it just means we can't free this bunch of tnodes later.
+	 */
+
+	tnl = YMALLOC(sizeof(yaffs_TnodeList));
+	if (!tnl) {
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR
+		   ("yaffs: Could not add tnodes to management list" TENDSTR)));
+		   return YAFFS_FAIL;
+	} else {
+		tnl->tnodes = newTnodes;
+		tnl->next = dev->allocatedTnodeList;
+		dev->allocatedTnodeList = tnl;
+	}
+
+	T(YAFFS_TRACE_ALLOCATE, (TSTR("yaffs: Tnodes added" TENDSTR)));
+
+	return YAFFS_OK;
+}
+
+/* GetTnode gets us a clean tnode. Tries to make allocate more if we run out */
+
+static yaffs_Tnode *yaffs_GetTnodeRaw(yaffs_Device *dev)
+{
+	yaffs_Tnode *tn = NULL;
+
+#ifdef CONFIG_YAFFS_VALGRIND_TEST
+	tn = YMALLOC(yaffs_CalcTnodeSize(dev));
+	if(tn)
+		dev->nTnodesCreated++;
+#else
+	/* If there are none left make more */
+	if (!dev->freeTnodes)
+		yaffs_CreateTnodes(dev, YAFFS_ALLOCATION_NTNODES);
+
+	if (dev->freeTnodes) {
+		tn = dev->freeTnodes;
+#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
+		if (tn->internal[YAFFS_NTNODES_INTERNAL] != (void *)1) {
+			/* Hoosterman, this thing looks like it isn't in the list */
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: Tnode list bug 1" TENDSTR)));
+		}
+#endif
+		dev->freeTnodes = dev->freeTnodes->internal[0];
+		dev->nFreeTnodes--;
+	}
+#endif
+	dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
+
+	return tn;
+}
+
+static yaffs_Tnode *yaffs_GetTnode(yaffs_Device *dev)
+{
+	yaffs_Tnode *tn = yaffs_GetTnodeRaw(dev);
+	int tnodeSize = yaffs_CalcTnodeSize(dev);
+
+	if (tn)
+		memset(tn, 0, tnodeSize);
+
+	return tn;
+}
+
+/* FreeTnode frees up a tnode and puts it back on the free list */
+static void yaffs_FreeTnode(yaffs_Device *dev, yaffs_Tnode *tn)
+{
+	if (tn) {
+#ifdef CONFIG_YAFFS_VALGRIND_TEST
+		YFREE(tn);
+		dev->nTnodesCreated--;
+#else
+#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
+		if (tn->internal[YAFFS_NTNODES_INTERNAL] != 0) {
+			/* Hoosterman, this thing looks like it is already in the list */
+			T(YAFFS_TRACE_ALWAYS,
+			  (TSTR("yaffs: Tnode list bug 2" TENDSTR)));
+		}
+		tn->internal[YAFFS_NTNODES_INTERNAL] = (void *)1;
+#endif
+		tn->internal[0] = dev->freeTnodes;
+		dev->freeTnodes = tn;
+		dev->nFreeTnodes++;
+#endif
+	}
+	dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
+}
+
+static void yaffs_DeinitialiseTnodes(yaffs_Device *dev)
+{
+	/* Free the list of allocated tnodes */
+	yaffs_TnodeList *tmp;
+
+	while (dev->allocatedTnodeList) {
+		tmp = dev->allocatedTnodeList->next;
+
+		YFREE(dev->allocatedTnodeList->tnodes);
+		YFREE(dev->allocatedTnodeList);
+		dev->allocatedTnodeList = tmp;
+
+	}
+
+	dev->freeTnodes = NULL;
+	dev->nFreeTnodes = 0;
+	dev->nTnodesCreated = 0;
+}
+
+static void yaffs_InitialiseTnodes(yaffs_Device *dev)
+{
+	dev->allocatedTnodeList = NULL;
+	dev->freeTnodes = NULL;
+	dev->nFreeTnodes = 0;
+	dev->nTnodesCreated = 0;
+}
+
+
+void yaffs_LoadLevel0Tnode(yaffs_Device *dev, yaffs_Tnode *tn, unsigned pos,
+		unsigned val)
+{
+	__u32 *map = (__u32 *)tn;
+	__u32 bitInMap;
+	__u32 bitInWord;
+	__u32 wordInMap;
+	__u32 mask;
+
+	pos &= YAFFS_TNODES_LEVEL0_MASK;
+	val >>= dev->chunkGroupBits;
+
+	bitInMap = pos * dev->tnodeWidth;
+	wordInMap = bitInMap / 32;
+	bitInWord = bitInMap & (32 - 1);
+
+	mask = dev->tnodeMask << bitInWord;
+
+	map[wordInMap] &= ~mask;
+	map[wordInMap] |= (mask & (val << bitInWord));
+
+	if (dev->tnodeWidth > (32 - bitInWord)) {
+		bitInWord = (32 - bitInWord);
+		wordInMap++;;
+		mask = dev->tnodeMask >> (/*dev->tnodeWidth -*/ bitInWord);
+		map[wordInMap] &= ~mask;
+		map[wordInMap] |= (mask & (val >> bitInWord));
+	}
+}
+
+static __u32 yaffs_GetChunkGroupBase(yaffs_Device *dev, yaffs_Tnode *tn,
+		unsigned pos)
+{
+	__u32 *map = (__u32 *)tn;
+	__u32 bitInMap;
+	__u32 bitInWord;
+	__u32 wordInMap;
+	__u32 val;
+
+	pos &= YAFFS_TNODES_LEVEL0_MASK;
+
+	bitInMap = pos * dev->tnodeWidth;
+	wordInMap = bitInMap / 32;
+	bitInWord = bitInMap & (32 - 1);
+
+	val = map[wordInMap] >> bitInWord;
+
+	if	(dev->tnodeWidth > (32 - bitInWord)) {
+		bitInWord = (32 - bitInWord);
+		wordInMap++;;
+		val |= (map[wordInMap] << bitInWord);
+	}
+
+	val &= dev->tnodeMask;
+	val <<= dev->chunkGroupBits;
+
+	return val;
+}
+
+/* ------------------- End of individual tnode manipulation -----------------*/
+
+/* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
+ * The look up tree is represented by the top tnode and the number of topLevel
+ * in the tree. 0 means only the level 0 tnode is in the tree.
+ */
+
+/* FindLevel0Tnode finds the level 0 tnode, if one exists. */
+static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,
+					yaffs_FileStructure *fStruct,
+					__u32 chunkId)
+{
+	yaffs_Tnode *tn = fStruct->top;
+	__u32 i;
+	int requiredTallness;
+	int level = fStruct->topLevel;
+
+	dev=dev;
+
+	/* Check sane level and chunk Id */
+	if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
+		return NULL;
+
+	if (chunkId > YAFFS_MAX_CHUNK_ID)
+		return NULL;
+
+	/* First check we're tall enough (ie enough topLevel) */
+
+	i = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
+	requiredTallness = 0;
+	while (i) {
+		i >>= YAFFS_TNODES_INTERNAL_BITS;
+		requiredTallness++;
+	}
+
+	if (requiredTallness > fStruct->topLevel)
+		return NULL; /* Not tall enough, so we can't find it */
+
+	/* Traverse down to level 0 */
+	while (level > 0 && tn) {
+		tn = tn->internal[(chunkId >>
+			(YAFFS_TNODES_LEVEL0_BITS +
+				(level - 1) *
+				YAFFS_TNODES_INTERNAL_BITS)) &
+			YAFFS_TNODES_INTERNAL_MASK];
+		level--;
+	}
+
+	return tn;
+}
+
+/* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
+ * This happens in two steps:
+ *  1. If the tree isn't tall enough, then make it taller.
+ *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
+ *
+ * Used when modifying the tree.
+ *
+ *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
+ *  be plugged into the ttree.
+ */
+
+static yaffs_Tnode *yaffs_AddOrFindLevel0Tnode(yaffs_Device *dev,
+					yaffs_FileStructure *fStruct,
+					__u32 chunkId,
+					yaffs_Tnode *passedTn)
+{
+	int requiredTallness;
+	int i;
+	int l;
+	yaffs_Tnode *tn;
+
+	__u32 x;
+
+
+	/* Check sane level and page Id */
+	if (fStruct->topLevel < 0 || fStruct->topLevel > YAFFS_TNODES_MAX_LEVEL)
+		return NULL;
+
+	if (chunkId > YAFFS_MAX_CHUNK_ID)
+		return NULL;
+
+	/* First check we're tall enough (ie enough topLevel) */
+
+	x = chunkId >> YAFFS_TNODES_LEVEL0_BITS;
+	requiredTallness = 0;
+	while (x) {
+		x >>= YAFFS_TNODES_INTERNAL_BITS;
+		requiredTallness++;
+	}
+
+
+	if (requiredTallness > fStruct->topLevel) {
+		/* Not tall enough, gotta make the tree taller */
+		for (i = fStruct->topLevel; i < requiredTallness; i++) {
+
+			tn = yaffs_GetTnode(dev);
+
+			if (tn) {
+				tn->internal[0] = fStruct->top;
+				fStruct->top = tn;
+				fStruct->topLevel++;
+			} else {
+				T(YAFFS_TRACE_ERROR,
+					(TSTR("yaffs: no more tnodes" TENDSTR)));
+				return NULL;
+			}
+		}
+	}
+
+	/* Traverse down to level 0, adding anything we need */
+
+	l = fStruct->topLevel;
+	tn = fStruct->top;
+
+	if (l > 0) {
+		while (l > 0 && tn) {
+			x = (chunkId >>
+			     (YAFFS_TNODES_LEVEL0_BITS +
+			      (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
+			    YAFFS_TNODES_INTERNAL_MASK;
+
+
+			if ((l > 1) && !tn->internal[x]) {
+				/* Add missing non-level-zero tnode */
+				tn->internal[x] = yaffs_GetTnode(dev);
+				if(!tn->internal[x])
+					return NULL;
+			} else if (l == 1) {
+				/* Looking from level 1 at level 0 */
+				if (passedTn) {
+					/* If we already have one, then release it.*/
+					if (tn->internal[x])
+						yaffs_FreeTnode(dev, tn->internal[x]);
+					tn->internal[x] = passedTn;
+
+				} else if (!tn->internal[x]) {
+					/* Don't have one, none passed in */
+					tn->internal[x] = yaffs_GetTnode(dev);
+					if(!tn->internal[x])
+						return NULL;
+				}
+			}
+
+			tn = tn->internal[x];
+			l--;
+		}
+	} else {
+		/* top is level 0 */
+		if (passedTn) {
+			memcpy(tn, passedTn, (dev->tnodeWidth * YAFFS_NTNODES_LEVEL0)/8);
+			yaffs_FreeTnode(dev, passedTn);
+		}
+	}
+
+	return tn;
+}
+
+static int yaffs_FindChunkInGroup(yaffs_Device *dev, int theChunk,
+				yaffs_ExtendedTags *tags, int objectId,
+				int chunkInInode)
+{
+	int j;
+
+	for (j = 0; theChunk && j < dev->chunkGroupSize; j++) {
+		if (yaffs_CheckChunkBit(dev, theChunk / dev->param.nChunksPerBlock,
+				theChunk % dev->param.nChunksPerBlock)) {
+			
+			if(dev->chunkGroupSize == 1)
+				return theChunk;
+			else {
+				yaffs_ReadChunkWithTagsFromNAND(dev, theChunk, NULL,
+								tags);
+				if (yaffs_TagsMatch(tags, objectId, chunkInInode)) {
+					/* found it; */
+					return theChunk;
+				}
+			}
+		}
+		theChunk++;
+	}
+	return -1;
+}
+
+#if 0
+/* Experimental code not being used yet. Might speed up file deletion */
+/* DeleteWorker scans backwards through the tnode tree and deletes all the
+ * chunks and tnodes in the file.
+ * Returns 1 if the tree was deleted.
+ * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
+ */
+
+static int yaffs_DeleteWorker(yaffs_Object *in, yaffs_Tnode *tn, __u32 level,
+			      int chunkOffset, int *limit)
+{
+	int i;
+	int chunkInInode;
+	int theChunk;
+	yaffs_ExtendedTags tags;
+	int foundChunk;
+	yaffs_Device *dev = in->myDev;
+
+	int allDone = 1;
+
+	if (tn) {
+		if (level > 0) {
+			for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
+			     i--) {
+				if (tn->internal[i]) {
+					if (limit && (*limit) < 0) {
+						allDone = 0;
+					} else {
+						allDone =
+							yaffs_DeleteWorker(in,
+								tn->
+								internal
+								[i],
+								level -
+								1,
+								(chunkOffset
+									<<
+									YAFFS_TNODES_INTERNAL_BITS)
+								+ i,
+								limit);
+					}
+					if (allDone) {
+						yaffs_FreeTnode(dev,
+								tn->
+								internal[i]);
+						tn->internal[i] = NULL;
+					}
+				}
+			}
+			return (allDone) ? 1 : 0;
+		} else if (level == 0) {
+			int hitLimit = 0;
+
+			for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
+					i--) {
+				theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
+				if (theChunk) {
+
+					chunkInInode = (chunkOffset <<
+						YAFFS_TNODES_LEVEL0_BITS) + i;
+
+					foundChunk =
+						yaffs_FindChunkInGroup(dev,
+								theChunk,
+								&tags,
+								in->objectId,
+								chunkInInode);
+
+					if (foundChunk > 0) {
+						yaffs_DeleteChunk(dev,
+								  foundChunk, 1,
+								  __LINE__);
+						in->nDataChunks--;
+						if (limit) {
+							*limit = *limit - 1;
+							if (*limit <= 0)
+								hitLimit = 1;
+						}
+
+					}
+
+					yaffs_LoadLevel0Tnode(dev, tn, i, 0);
+				}
+
+			}
+			return (i < 0) ? 1 : 0;
+
+		}
+
+	}
+
+	return 1;
+
+}
+
+#endif
+
+static void yaffs_SoftDeleteChunk(yaffs_Device *dev, int chunk)
+{
+	yaffs_BlockInfo *theBlock;
+	unsigned blockNo;
+
+	T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
+
+	blockNo =  chunk / dev->param.nChunksPerBlock;
+	theBlock = yaffs_GetBlockInfo(dev, blockNo);
+	if (theBlock) {
+		theBlock->softDeletions++;
+		dev->nFreeChunks++;
+		yaffs_UpdateOldestDirtySequence(dev, blockNo, theBlock);
+	}
+}
+
+/* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
+ * All soft deleting does is increment the block's softdelete count and pulls the chunk out
+ * of the tnode.
+ * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
+ */
+
+static int yaffs_SoftDeleteWorker(yaffs_Object *in, yaffs_Tnode *tn,
+				  __u32 level, int chunkOffset)
+{
+	int i;
+	int theChunk;
+	int allDone = 1;
+	yaffs_Device *dev = in->myDev;
+
+	if (tn) {
+		if (level > 0) {
+
+			for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
+			     i--) {
+				if (tn->internal[i]) {
+					allDone =
+					    yaffs_SoftDeleteWorker(in,
+								   tn->
+								   internal[i],
+								   level - 1,
+								   (chunkOffset
+								    <<
+								    YAFFS_TNODES_INTERNAL_BITS)
+								   + i);
+					if (allDone) {
+						yaffs_FreeTnode(dev,
+								tn->
+								internal[i]);
+						tn->internal[i] = NULL;
+					} else {
+						/* Hoosterman... how could this happen? */
+					}
+				}
+			}
+			return (allDone) ? 1 : 0;
+		} else if (level == 0) {
+
+			for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
+				theChunk = yaffs_GetChunkGroupBase(dev, tn, i);
+				if (theChunk) {
+					/* Note this does not find the real chunk, only the chunk group.
+					 * We make an assumption that a chunk group is not larger than
+					 * a block.
+					 */
+					yaffs_SoftDeleteChunk(dev, theChunk);
+					yaffs_LoadLevel0Tnode(dev, tn, i, 0);
+				}
+
+			}
+			return 1;
+
+		}
+
+	}
+
+	return 1;
+
+}
+
+static void yaffs_SoftDeleteFile(yaffs_Object *obj)
+{
+	if (obj->deleted &&
+	    obj->variantType == YAFFS_OBJECT_TYPE_FILE && !obj->softDeleted) {
+		if (obj->nDataChunks <= 0) {
+			/* Empty file with no duplicate object headers, just delete it immediately */
+			yaffs_FreeTnode(obj->myDev,
+					obj->variant.fileVariant.top);
+			obj->variant.fileVariant.top = NULL;
+			T(YAFFS_TRACE_TRACING,
+			  (TSTR("yaffs: Deleting empty file %d" TENDSTR),
+			   obj->objectId));
+			yaffs_DoGenericObjectDeletion(obj);
+		} else {
+			yaffs_SoftDeleteWorker(obj,
+					       obj->variant.fileVariant.top,
+					       obj->variant.fileVariant.
+					       topLevel, 0);
+			obj->softDeleted = 1;
+		}
+	}
+}
+
+/* Pruning removes any part of the file structure tree that is beyond the
+ * bounds of the file (ie that does not point to chunks).
+ *
+ * A file should only get pruned when its size is reduced.
+ *
+ * Before pruning, the chunks must be pulled from the tree and the
+ * level 0 tnode entries must be zeroed out.
+ * Could also use this for file deletion, but that's probably better handled
+ * by a special case.
+ *
+ * This function is recursive. For levels > 0 the function is called again on
+ * any sub-tree. For level == 0 we just check if the sub-tree has data.
+ * If there is no data in a subtree then it is pruned.
+ */
+
+static yaffs_Tnode *yaffs_PruneWorker(yaffs_Device *dev, yaffs_Tnode *tn,
+				__u32 level, int del0)
+{
+	int i;
+	int hasData;
+
+	if (tn) {
+		hasData = 0;
+
+		if(level > 0){
+			for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
+				if (tn->internal[i]) {
+					tn->internal[i] =
+						yaffs_PruneWorker(dev, tn->internal[i],
+							level - 1,
+							(i == 0) ? del0 : 1);
+				}
+
+				if (tn->internal[i])
+					hasData++;
+			}
+		} else {
+			int tnodeSize_u32 = yaffs_CalcTnodeSize(dev)/sizeof(__u32);
+			__u32 *map = (__u32 *)tn;
+
+                        for(i = 0; !hasData && i < tnodeSize_u32; i++){
+                                if(map[i])
+                                        hasData++;
+                        }
+                }
+
+		if (hasData == 0 && del0) {
+			/* Free and return NULL */
+
+			yaffs_FreeTnode(dev, tn);
+			tn = NULL;
+		}
+
+	}
+
+	return tn;
+
+}
+
+static int yaffs_PruneFileStructure(yaffs_Device *dev,
+				yaffs_FileStructure *fStruct)
+{
+	int i;
+	int hasData;
+	int done = 0;
+	yaffs_Tnode *tn;
+
+	if (fStruct->topLevel > 0) {
+		fStruct->top =
+		    yaffs_PruneWorker(dev, fStruct->top, fStruct->topLevel, 0);
+
+		/* Now we have a tree with all the non-zero branches NULL but the height
+		 * is the same as it was.
+		 * Let's see if we can trim internal tnodes to shorten the tree.
+		 * We can do this if only the 0th element in the tnode is in use
+		 * (ie all the non-zero are NULL)
+		 */
+
+		while (fStruct->topLevel && !done) {
+			tn = fStruct->top;
+
+			hasData = 0;
+			for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
+				if (tn->internal[i])
+					hasData++;
+			}
+
+			if (!hasData) {
+				fStruct->top = tn->internal[0];
+				fStruct->topLevel--;
+				yaffs_FreeTnode(dev, tn);
+			} else {
+				done = 1;
+			}
+		}
+	}
+
+	return YAFFS_OK;
+}
+
+/*-------------------- End of File Structure functions.-------------------*/
+
+/* yaffs_CreateFreeObjects creates a bunch more objects and
+ * adds them to the object free list.
+ */
+static int yaffs_CreateFreeObjects(yaffs_Device *dev, int nObjects)
+{
+	int i;
+	yaffs_Object *newObjects;
+	yaffs_ObjectList *list;
+
+	if (nObjects < 1)
+		return YAFFS_OK;
+
+	/* make these things */
+	newObjects = YMALLOC(nObjects * sizeof(yaffs_Object));
+	list = YMALLOC(sizeof(yaffs_ObjectList));
+
+	if (!newObjects || !list) {
+		if (newObjects){
+			YFREE(newObjects);
+			newObjects = NULL;
+		}
+		if (list){
+			YFREE(list);
+			list = NULL;
+		}
+		T(YAFFS_TRACE_ALLOCATE,
+		  (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* Hook them into the free list */
+	for (i = 0; i < nObjects - 1; i++) {
+		newObjects[i].siblings.next =
+				(struct ylist_head *)(&newObjects[i + 1]);
+	}
+
+	newObjects[nObjects - 1].siblings.next = (void *)dev->freeObjects;
+	dev->freeObjects = newObjects;
+	dev->nFreeObjects += nObjects;
+	dev->nObjectsCreated += nObjects;
+
+	/* Now add this bunch of Objects to a list for freeing up. */
+
+	list->objects = newObjects;
+	list->next = dev->allocatedObjectList;
+	dev->allocatedObjectList = list;
+
+	return YAFFS_OK;
+}
+
+
+/* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
+static yaffs_Object *yaffs_AllocateEmptyObject(yaffs_Device *dev)
+{
+	yaffs_Object *tn = NULL;
+
+#ifdef CONFIG_YAFFS_VALGRIND_TEST
+	tn = YMALLOC(sizeof(yaffs_Object));
+	if(tn)
+		dev->nObjectsCreated++;
+#else
+	/* If there are none left make more */
+	if (!dev->freeObjects)
+		yaffs_CreateFreeObjects(dev, YAFFS_ALLOCATION_NOBJECTS);
+
+	if (dev->freeObjects) {
+		tn = dev->freeObjects;
+		dev->freeObjects =
+			(yaffs_Object *) (dev->freeObjects->siblings.next);
+		dev->nFreeObjects--;
+	}
+#endif
+	if (tn) {
+		/* Now sweeten it up... */
+
+		memset(tn, 0, sizeof(yaffs_Object));
+		tn->beingCreated = 1;
+
+		tn->myDev = dev;
+		tn->hdrChunk = 0;
+		tn->variantType = YAFFS_OBJECT_TYPE_UNKNOWN;
+		YINIT_LIST_HEAD(&(tn->hardLinks));
+		YINIT_LIST_HEAD(&(tn->hashLink));
+		YINIT_LIST_HEAD(&tn->siblings);
+
+
+		/* Now make the directory sane */
+		if (dev->rootDir) {
+			tn->parent = dev->rootDir;
+			ylist_add(&(tn->siblings), &dev->rootDir->variant.directoryVariant.children);
+		}
+
+		/* Add it to the lost and found directory.
+		 * NB Can't put root or lostNFound in lostNFound so
+		 * check if lostNFound exists first
+		 */
+		if (dev->lostNFoundDir)
+			yaffs_AddObjectToDirectory(dev->lostNFoundDir, tn);
+
+		tn->beingCreated = 0;
+	}
+
+	dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
+
+	return tn;
+}
+
+static yaffs_Object *yaffs_CreateFakeDirectory(yaffs_Device *dev, int number,
+					       __u32 mode)
+{
+
+	yaffs_Object *obj =
+	    yaffs_CreateNewObject(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
+	if (obj) {
+		obj->fake = 1;		/* it is fake so it might have no NAND presence... */
+		obj->renameAllowed = 0;	/* ... and we're not allowed to rename it... */
+		obj->unlinkAllowed = 0;	/* ... or unlink it */
+		obj->deleted = 0;
+		obj->unlinked = 0;
+		obj->yst_mode = mode;
+		obj->myDev = dev;
+		obj->hdrChunk = 0;	/* Not a valid chunk. */
+	}
+
+	return obj;
+
+}
+
+static void yaffs_UnhashObject(yaffs_Object *tn)
+{
+	int bucket;
+	yaffs_Device *dev = tn->myDev;
+
+	/* If it is still linked into the bucket list, free from the list */
+	if (!ylist_empty(&tn->hashLink)) {
+		ylist_del_init(&tn->hashLink);
+		bucket = yaffs_HashFunction(tn->objectId);
+		dev->objectBucket[bucket].count--;
+	}
+}
+
+/*  FreeObject frees up a Object and puts it back on the free list */
+static void yaffs_FreeObject(yaffs_Object *tn)
+{
+	yaffs_Device *dev = tn->myDev;
+
+	T(YAFFS_TRACE_OS, (TSTR("FreeObject %p inode %p"TENDSTR), tn, tn->myInode));
+
+	if (!tn)
+		YBUG();
+	if (tn->parent)
+		YBUG();
+	if (!ylist_empty(&tn->siblings))
+		YBUG();
+
+
+	if (tn->myInode) {
+		/* We're still hooked up to a cached inode.
+		 * Don't delete now, but mark for later deletion
+		 */
+		tn->deferedFree = 1;
+		return;
+	}
+
+	yaffs_UnhashObject(tn);
+
+#ifdef CONFIG_YAFFS_VALGRIND_TEST
+	YFREE(tn);
+	dev->nObjectsCreated--;
+	tn = NULL;
+#else
+	/* Link into the free list. */
+	tn->siblings.next = (struct ylist_head *)(dev->freeObjects);
+	dev->freeObjects = tn;
+	dev->nFreeObjects++;
+#endif
+	dev->nCheckpointBlocksRequired = 0; /* force recalculation*/
+}
+
+
+void yaffs_HandleDeferedFree(yaffs_Object *obj)
+{
+	if (obj->deferedFree)
+		yaffs_FreeObject(obj);
+}
+
+
+static void yaffs_DeinitialiseObjects(yaffs_Device *dev)
+{
+	/* Free the list of allocated Objects */
+
+	yaffs_ObjectList *tmp;
+
+	while (dev->allocatedObjectList) {
+		tmp = dev->allocatedObjectList->next;
+		YFREE(dev->allocatedObjectList->objects);
+		YFREE(dev->allocatedObjectList);
+
+		dev->allocatedObjectList = tmp;
+	}
+
+	dev->freeObjects = NULL;
+	dev->nFreeObjects = 0;
+	dev->nObjectsCreated = 0;
+}
+
+static void yaffs_InitialiseObjects(yaffs_Device *dev)
+{
+	int i;
+
+	dev->allocatedObjectList = NULL;
+	dev->freeObjects = NULL;
+	dev->nFreeObjects = 0;
+
+	for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
+		YINIT_LIST_HEAD(&dev->objectBucket[i].list);
+		dev->objectBucket[i].count = 0;
+	}
+}
+
+static int yaffs_FindNiceObjectBucket(yaffs_Device *dev)
+{
+	int i;
+	int l = 999;
+	int lowest = 999999;
+
+
+	/* Search for the shortest list or one that
+	 * isn't too long.
+	 */
+
+	for (i = 0; i < 10 && lowest > 4; i++) {
+		dev->bucketFinder++;
+		dev->bucketFinder %= YAFFS_NOBJECT_BUCKETS;
+		if (dev->objectBucket[dev->bucketFinder].count < lowest) {
+			lowest = dev->objectBucket[dev->bucketFinder].count;
+			l = dev->bucketFinder;
+		}
+
+	}
+
+	return l;
+}
+
+static int yaffs_CreateNewObjectNumber(yaffs_Device *dev)
+{
+	int bucket = yaffs_FindNiceObjectBucket(dev);
+
+	/* Now find an object value that has not already been taken
+	 * by scanning the list.
+	 */
+
+	int found = 0;
+	struct ylist_head *i;
+
+	__u32 n = (__u32) bucket;
+
+	/* yaffs_CheckObjectHashSanity();  */
+
+	while (!found) {
+		found = 1;
+		n += YAFFS_NOBJECT_BUCKETS;
+		if (1 || dev->objectBucket[bucket].count > 0) {
+			ylist_for_each(i, &dev->objectBucket[bucket].list) {
+				/* If there is already one in the list */
+				if (i && ylist_entry(i, yaffs_Object,
+						hashLink)->objectId == n) {
+					found = 0;
+				}
+			}
+		}
+	}
+
+	return n;
+}
+
+static void yaffs_HashObject(yaffs_Object *in)
+{
+	int bucket = yaffs_HashFunction(in->objectId);
+	yaffs_Device *dev = in->myDev;
+
+	ylist_add(&in->hashLink, &dev->objectBucket[bucket].list);
+	dev->objectBucket[bucket].count++;
+}
+
+yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev, __u32 number)
+{
+	int bucket = yaffs_HashFunction(number);
+	struct ylist_head *i;
+	yaffs_Object *in;
+
+	ylist_for_each(i, &dev->objectBucket[bucket].list) {
+		/* Look if it is in the list */
+		if (i) {
+			in = ylist_entry(i, yaffs_Object, hashLink);
+			if (in->objectId == number) {
+
+				/* Don't tell the VFS about this one if it is defered free */
+				if (in->deferedFree)
+					return NULL;
+
+				return in;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+yaffs_Object *yaffs_CreateNewObject(yaffs_Device *dev, int number,
+				    yaffs_ObjectType type)
+{
+	yaffs_Object *theObject=NULL;
+	yaffs_Tnode *tn = NULL;
+
+	if (number < 0)
+		number = yaffs_CreateNewObjectNumber(dev);
+
+	if (type == YAFFS_OBJECT_TYPE_FILE) {
+		tn = yaffs_GetTnode(dev);
+		if (!tn)
+			return NULL;
+	}
+
+	theObject = yaffs_AllocateEmptyObject(dev);
+	if (!theObject){
+		if(tn)
+			yaffs_FreeTnode(dev,tn);
+		return NULL;
+	}
+
+
+	if (theObject) {
+		theObject->fake = 0;
+		theObject->renameAllowed = 1;
+		theObject->unlinkAllowed = 1;
+		theObject->objectId = number;
+		yaffs_HashObject(theObject);
+		theObject->variantType = type;
+#ifdef CONFIG_YAFFS_WINCE
+		yfsd_WinFileTimeNow(theObject->win_atime);
+		theObject->win_ctime[0] = theObject->win_mtime[0] =
+		    theObject->win_atime[0];
+		theObject->win_ctime[1] = theObject->win_mtime[1] =
+		    theObject->win_atime[1];
+
+#else
+
+		theObject->yst_atime = theObject->yst_mtime =
+		    theObject->yst_ctime = Y_CURRENT_TIME;
+#endif
+		switch (type) {
+		case YAFFS_OBJECT_TYPE_FILE:
+			theObject->variant.fileVariant.fileSize = 0;
+			theObject->variant.fileVariant.scannedFileSize = 0;
+			theObject->variant.fileVariant.shrinkSize = 0xFFFFFFFF;	/* max __u32 */
+			theObject->variant.fileVariant.topLevel = 0;
+			theObject->variant.fileVariant.top = tn;
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			YINIT_LIST_HEAD(&theObject->variant.directoryVariant.
+					children);
+			YINIT_LIST_HEAD(&theObject->variant.directoryVariant.
+					dirty);
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+			/* No action required */
+			break;
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+			/* todo this should not happen */
+			break;
+		}
+	}
+
+	return theObject;
+}
+
+static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device *dev,
+						      int number,
+						      yaffs_ObjectType type)
+{
+	yaffs_Object *theObject = NULL;
+
+	if (number > 0)
+		theObject = yaffs_FindObjectByNumber(dev, number);
+
+	if (!theObject)
+		theObject = yaffs_CreateNewObject(dev, number, type);
+
+	return theObject;
+
+}
+
+
+static YCHAR *yaffs_CloneString(const YCHAR *str)
+{
+	YCHAR *newStr = NULL;
+	int len;
+
+	if (!str)
+		str = _Y("");
+
+	len = yaffs_strnlen(str,YAFFS_MAX_ALIAS_LENGTH);
+	newStr = YMALLOC((len + 1) * sizeof(YCHAR));
+	if (newStr){
+		yaffs_strncpy(newStr, str,len);
+		newStr[len] = 0;
+	}
+	return newStr;
+
+}
+
+/*
+ * Mknod (create) a new object.
+ * equivalentObject only has meaning for a hard link;
+ * aliasString only has meaning for a symlink.
+ * rdev only has meaning for devices (a subset of special objects)
+ */
+
+static yaffs_Object *yaffs_MknodObject(yaffs_ObjectType type,
+				       yaffs_Object *parent,
+				       const YCHAR *name,
+				       __u32 mode,
+				       __u32 uid,
+				       __u32 gid,
+				       yaffs_Object *equivalentObject,
+				       const YCHAR *aliasString, __u32 rdev)
+{
+	yaffs_Object *in;
+	YCHAR *str = NULL;
+
+	yaffs_Device *dev = parent->myDev;
+
+	/* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
+	if (yaffs_FindObjectByName(parent, name))
+		return NULL;
+
+	if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
+		str = yaffs_CloneString(aliasString);
+		if (!str)
+			return NULL;
+	}
+
+	in = yaffs_CreateNewObject(dev, -1, type);
+
+	if (!in){
+		if(str)
+			YFREE(str);
+		return NULL;
+	}
+
+
+
+
+
+	if (in) {
+		in->hdrChunk = 0;
+		in->valid = 1;
+		in->variantType = type;
+
+		in->yst_mode = mode;
+
+#ifdef CONFIG_YAFFS_WINCE
+		yfsd_WinFileTimeNow(in->win_atime);
+		in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
+		in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
+
+#else
+		in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
+
+		in->yst_rdev = rdev;
+		in->yst_uid = uid;
+		in->yst_gid = gid;
+#endif
+		in->nDataChunks = 0;
+
+		yaffs_SetObjectName(in, name);
+		in->dirty = 1;
+
+		yaffs_AddObjectToDirectory(parent, in);
+
+		in->myDev = parent->myDev;
+
+		switch (type) {
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			in->variant.symLinkVariant.alias = str;
+			break;
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+			in->variant.hardLinkVariant.equivalentObject =
+				equivalentObject;
+			in->variant.hardLinkVariant.equivalentObjectId =
+				equivalentObject->objectId;
+			ylist_add(&in->hardLinks, &equivalentObject->hardLinks);
+			break;
+		case YAFFS_OBJECT_TYPE_FILE:
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+			/* do nothing */
+			break;
+		}
+
+		if (yaffs_UpdateObjectHeader(in, name, 0, 0, 0) < 0) {
+			/* Could not create the object header, fail the creation */
+			yaffs_DeleteObject(in);
+			in = NULL;
+		}
+
+		yaffs_UpdateParent(parent);
+	}
+
+	return in;
+}
+
+yaffs_Object *yaffs_MknodFile(yaffs_Object *parent, const YCHAR *name,
+			__u32 mode, __u32 uid, __u32 gid)
+{
+	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
+				uid, gid, NULL, NULL, 0);
+}
+
+yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid)
+{
+	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
+				 mode, uid, gid, NULL, NULL, 0);
+}
+
+yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid, __u32 rdev)
+{
+	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
+				 uid, gid, NULL, NULL, rdev);
+}
+
+yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid,
+				const YCHAR *alias)
+{
+	return yaffs_MknodObject(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
+				uid, gid, NULL, alias, 0);
+}
+
+/* yaffs_Link returns the object id of the equivalent object.*/
+yaffs_Object *yaffs_Link(yaffs_Object *parent, const YCHAR *name,
+			yaffs_Object *equivalentObject)
+{
+	/* Get the real object in case we were fed a hard link as an equivalent object */
+	equivalentObject = yaffs_GetEquivalentObject(equivalentObject);
+
+	if (yaffs_MknodObject
+	    (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
+	     equivalentObject, NULL, 0)) {
+		return equivalentObject;
+	} else {
+		return NULL;
+	}
+
+}
+
+static int yaffs_ChangeObjectName(yaffs_Object *obj, yaffs_Object *newDir,
+				const YCHAR *newName, int force, int shadows)
+{
+	int unlinkOp;
+	int deleteOp;
+
+	yaffs_Object *existingTarget;
+
+	if (newDir == NULL)
+		newDir = obj->parent;	/* use the old directory */
+
+	if (newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_ChangeObjectName: newDir is not a directory"
+		    TENDSTR)));
+		YBUG();
+	}
+
+	/* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
+	if (obj->myDev->param.isYaffs2)
+		unlinkOp = (newDir == obj->myDev->unlinkedDir);
+	else
+		unlinkOp = (newDir == obj->myDev->unlinkedDir
+			    && obj->variantType == YAFFS_OBJECT_TYPE_FILE);
+
+	deleteOp = (newDir == obj->myDev->deletedDir);
+
+	existingTarget = yaffs_FindObjectByName(newDir, newName);
+
+	/* If the object is a file going into the unlinked directory,
+	 *   then it is OK to just stuff it in since duplicate names are allowed.
+	 *   else only proceed if the new name does not exist and if we're putting
+	 *   it into a directory.
+	 */
+	if ((unlinkOp ||
+	     deleteOp ||
+	     force ||
+	     (shadows > 0) ||
+	     !existingTarget) &&
+	    newDir->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) {
+		yaffs_SetObjectName(obj, newName);
+		obj->dirty = 1;
+
+		yaffs_AddObjectToDirectory(newDir, obj);
+
+		if (unlinkOp)
+			obj->unlinked = 1;
+
+		/* If it is a deletion then we mark it as a shrink for gc purposes. */
+		if (yaffs_UpdateObjectHeader(obj, newName, 0, deleteOp, shadows) >= 0)
+			return YAFFS_OK;
+	}
+
+	return YAFFS_FAIL;
+}
+
+int yaffs_RenameObject(yaffs_Object *oldDir, const YCHAR *oldName,
+		yaffs_Object *newDir, const YCHAR *newName)
+{
+	yaffs_Object *obj = NULL;
+	yaffs_Object *existingTarget = NULL;
+	int force = 0;
+	int result;
+	yaffs_Device *dev;
+
+
+	if (!oldDir || oldDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
+		YBUG();
+	if (!newDir || newDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
+		YBUG();
+
+	dev = oldDir->myDev;
+
+#ifdef CONFIG_YAFFS_CASE_INSENSITIVE
+	/* Special case for case insemsitive systems (eg. WinCE).
+	 * While look-up is case insensitive, the name isn't.
+	 * Therefore we might want to change x.txt to X.txt
+	*/
+	if (oldDir == newDir && yaffs_strcmp(oldName, newName) == 0)
+		force = 1;
+#endif
+
+	if(yaffs_strnlen(newName,YAFFS_MAX_NAME_LENGTH+1) > YAFFS_MAX_NAME_LENGTH)
+		/* ENAMETOOLONG */
+		return YAFFS_FAIL;
+
+	obj = yaffs_FindObjectByName(oldDir, oldName);
+
+	if (obj && obj->renameAllowed) {
+
+		/* Now do the handling for an existing target, if there is one */
+
+		existingTarget = yaffs_FindObjectByName(newDir, newName);
+		if (existingTarget &&
+			existingTarget->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
+			!ylist_empty(&existingTarget->variant.directoryVariant.children)) {
+			/* There is a target that is a non-empty directory, so we fail */
+			return YAFFS_FAIL;	/* EEXIST or ENOTEMPTY */
+		} else if (existingTarget && existingTarget != obj) {
+			/* Nuke the target first, using shadowing,
+			 * but only if it isn't the same object.
+			 *
+			 * Note we must disable gc otherwise it can mess up the shadowing.
+			 *
+			 */
+			dev->gcDisable=1;
+			yaffs_ChangeObjectName(obj, newDir, newName, force,
+						existingTarget->objectId);
+			existingTarget->isShadowed = 1;
+			yaffs_UnlinkObject(existingTarget);
+			dev->gcDisable=0;
+		}
+
+		result = yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
+
+		yaffs_UpdateParent(oldDir);
+		if(newDir != oldDir)
+			yaffs_UpdateParent(newDir);
+		
+		return result;
+	}
+	return YAFFS_FAIL;
+}
+
+/*------------------------- Block Management and Page Allocation ----------------*/
+
+static int yaffs_InitialiseBlocks(yaffs_Device *dev)
+{
+	int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
+
+	dev->blockInfo = NULL;
+	dev->chunkBits = NULL;
+
+	dev->allocationBlock = -1;	/* force it to get a new one */
+
+	/* If the first allocation strategy fails, thry the alternate one */
+	dev->blockInfo = YMALLOC(nBlocks * sizeof(yaffs_BlockInfo));
+	if (!dev->blockInfo) {
+		dev->blockInfo = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockInfo));
+		dev->blockInfoAlt = 1;
+	} else
+		dev->blockInfoAlt = 0;
+
+	if (dev->blockInfo) {
+		/* Set up dynamic blockinfo stuff. */
+		dev->chunkBitmapStride = (dev->param.nChunksPerBlock + 7) / 8; /* round up bytes */
+		dev->chunkBits = YMALLOC(dev->chunkBitmapStride * nBlocks);
+		if (!dev->chunkBits) {
+			dev->chunkBits = YMALLOC_ALT(dev->chunkBitmapStride * nBlocks);
+			dev->chunkBitsAlt = 1;
+		} else
+			dev->chunkBitsAlt = 0;
+	}
+
+	if (dev->blockInfo && dev->chunkBits) {
+		memset(dev->blockInfo, 0, nBlocks * sizeof(yaffs_BlockInfo));
+		memset(dev->chunkBits, 0, dev->chunkBitmapStride * nBlocks);
+		return YAFFS_OK;
+	}
+
+	return YAFFS_FAIL;
+}
+
+static void yaffs_DeinitialiseBlocks(yaffs_Device *dev)
+{
+	if (dev->blockInfoAlt && dev->blockInfo)
+		YFREE_ALT(dev->blockInfo);
+	else if (dev->blockInfo)
+		YFREE(dev->blockInfo);
+
+	dev->blockInfoAlt = 0;
+
+	dev->blockInfo = NULL;
+
+	if (dev->chunkBitsAlt && dev->chunkBits)
+		YFREE_ALT(dev->chunkBits);
+	else if (dev->chunkBits)
+		YFREE(dev->chunkBits);
+	dev->chunkBitsAlt = 0;
+	dev->chunkBits = NULL;
+}
+
+static int yaffs_BlockNotDisqualifiedFromGC(yaffs_Device *dev,
+					yaffs_BlockInfo *bi)
+{
+
+	if (!dev->param.isYaffs2)
+		return 1;	/* disqualification only applies to yaffs2. */
+
+	if (!bi->hasShrinkHeader)
+		return 1;	/* can gc */
+
+	yaffs_FindOldestDirtySequence(dev);
+
+	/* Can't do gc of this block if there are any blocks older than this one that have
+	 * discarded pages.
+	 */
+	return (bi->sequenceNumber <= dev->oldestDirtySequence);
+}
+
+/*
+ * yaffs_FindRefreshBlock()
+ * periodically finds the oldest full block by sequence number for refreshing.
+ * Only for yaffs2.
+ */
+static __u32 yaffs_FindRefreshBlock(yaffs_Device *dev)
+{
+	__u32 b ;
+
+	__u32 oldest = 0;
+	__u32 oldestSequence = 0;
+
+	yaffs_BlockInfo *bi;
+
+	/*
+	 * If refresh period < 10 then refreshing is disabled.
+	 */
+	if(dev->param.refreshPeriod < 10 ||
+		!dev->param.isYaffs2)
+	        return oldest;
+
+        /*
+         * Fix broken values.
+         */
+        if(dev->refreshSkip > dev->param.refreshPeriod)
+                dev->refreshSkip = dev->param.refreshPeriod;
+
+	if(dev->refreshSkip > 0)
+	        return oldest;
+
+	/*
+	 * Refresh skip is now zero.
+	 * We'll do a refresh this time around....
+	 * Update the refresh skip and find the oldest block.
+	 */
+	dev->refreshSkip = dev->param.refreshPeriod;
+	dev->refreshCount++;
+	bi = dev->blockInfo;
+	for (b = dev->internalStartBlock; b <=dev->internalEndBlock; b++){
+
+		if (bi->blockState == YAFFS_BLOCK_STATE_FULL){
+
+			if(oldest < 1 ||
+                                bi->sequenceNumber < oldestSequence){
+                                oldest = b;
+                                oldestSequence = bi->sequenceNumber;
+                        }
+		}
+		bi++;
+	}
+
+	if (oldest > 0) {
+		T(YAFFS_TRACE_GC,
+		  (TSTR("GC refresh count %d selected block %d with sequenceNumber %d" TENDSTR),
+		   dev->refreshCount, oldest, oldestSequence));
+	}
+
+	return oldest;
+}
+
+
+static void yaffs_BlockBecameDirty(yaffs_Device *dev, int blockNo)
+{
+	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, blockNo);
+
+	int erasedOk = 0;
+
+	/* If the block is still healthy erase it and mark as clean.
+	 * If the block has had a data failure, then retire it.
+	 */
+
+	T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
+		(TSTR("yaffs_BlockBecameDirty block %d state %d %s"TENDSTR),
+		blockNo, bi->blockState, (bi->needsRetiring) ? "needs retiring" : ""));
+
+	yaffs_ClearOldestDirtySequence(dev,bi);
+
+	bi->blockState = YAFFS_BLOCK_STATE_DIRTY;
+
+	/* If this is the block being garbage collected then stop gc'ing this block */
+	if(blockNo == dev->gcBlock)
+		dev->gcBlock = 0;
+
+	/* If this block is currently the best candidate for gc then drop as a candidate */
+	if(blockNo == dev->gcDirtiest){
+		dev->gcDirtiest = 0;
+		dev->gcPagesInUse = 0;
+	}
+
+	if (!bi->needsRetiring) {
+		yaffs_InvalidateCheckpoint(dev);
+		erasedOk = yaffs_EraseBlockInNAND(dev, blockNo);
+		if (!erasedOk) {
+			dev->nErasureFailures++;
+			T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+			  (TSTR("**>> Erasure failed %d" TENDSTR), blockNo));
+		}
+	}
+
+	if (erasedOk &&
+	    ((yaffs_traceMask & YAFFS_TRACE_ERASE) || !yaffs_SkipVerification(dev))) {
+		int i;
+		for (i = 0; i < dev->param.nChunksPerBlock; i++) {
+			if (!yaffs_CheckChunkErased
+			    (dev, blockNo * dev->param.nChunksPerBlock + i)) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   (">>Block %d erasure supposedly OK, but chunk %d not erased"
+				    TENDSTR), blockNo, i));
+			}
+		}
+	}
+
+	if (erasedOk) {
+		/* Clean it up... */
+		bi->blockState = YAFFS_BLOCK_STATE_EMPTY;
+		bi->sequenceNumber = 0;
+		dev->nErasedBlocks++;
+		bi->pagesInUse = 0;
+		bi->softDeletions = 0;
+		bi->hasShrinkHeader = 0;
+		bi->skipErasedCheck = 1;  /* This is clean, so no need to check */
+		bi->gcPrioritise = 0;
+		yaffs_ClearChunkBits(dev, blockNo);
+
+		T(YAFFS_TRACE_ERASE,
+		  (TSTR("Erased block %d" TENDSTR), blockNo));
+	} else {
+		dev->nFreeChunks -= dev->param.nChunksPerBlock;	/* We lost a block of free space */
+
+		yaffs_RetireBlock(dev, blockNo);
+		T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+		  (TSTR("**>> Block %d retired" TENDSTR), blockNo));
+	}
+}
+
+static int yaffs_FindBlockForAllocation(yaffs_Device *dev)
+{
+	int i;
+
+	yaffs_BlockInfo *bi;
+
+	if (dev->nErasedBlocks < 1) {
+		/* Hoosterman we've got a problem.
+		 * Can't get space to gc
+		 */
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR("yaffs tragedy: no more erased blocks" TENDSTR)));
+
+		return -1;
+	}
+
+	/* Find an empty block. */
+
+	for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
+		dev->allocationBlockFinder++;
+		if (dev->allocationBlockFinder < dev->internalStartBlock
+		    || dev->allocationBlockFinder > dev->internalEndBlock) {
+			dev->allocationBlockFinder = dev->internalStartBlock;
+		}
+
+		bi = yaffs_GetBlockInfo(dev, dev->allocationBlockFinder);
+
+		if (bi->blockState == YAFFS_BLOCK_STATE_EMPTY) {
+			bi->blockState = YAFFS_BLOCK_STATE_ALLOCATING;
+			dev->sequenceNumber++;
+			bi->sequenceNumber = dev->sequenceNumber;
+			dev->nErasedBlocks--;
+			T(YAFFS_TRACE_ALLOCATE,
+			  (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
+			   dev->allocationBlockFinder, dev->sequenceNumber,
+			   dev->nErasedBlocks));
+			return dev->allocationBlockFinder;
+		}
+	}
+
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR
+	   ("yaffs tragedy: no more erased blocks, but there should have been %d"
+	    TENDSTR), dev->nErasedBlocks));
+
+	return -1;
+}
+
+
+
+static int yaffs_CheckpointRequired(yaffs_Device *dev)
+{
+	int nblocks = dev->internalEndBlock - dev->internalStartBlock + 1 ;
+	return dev->param.isYaffs2 &&
+		!dev->param.skipCheckpointWrite &&
+		(nblocks >= YAFFS_CHECKPOINT_MIN_BLOCKS);
+}
+static int yaffs_CalcCheckpointBlocksRequired(yaffs_Device *dev)
+{
+	if (!dev->nCheckpointBlocksRequired &&
+		yaffs_CheckpointRequired(dev)){
+		/* Not a valid value so recalculate */
+		int nBytes = 0;
+		int nBlocks;
+		int devBlocks = (dev->param.endBlock - dev->param.startBlock + 1);
+		int tnodeSize = yaffs_CalcTnodeSize(dev);
+
+		nBytes += sizeof(yaffs_CheckpointValidity);
+		nBytes += sizeof(yaffs_CheckpointDevice);
+		nBytes += devBlocks * sizeof(yaffs_BlockInfo);
+		nBytes += devBlocks * dev->chunkBitmapStride;
+		nBytes += (sizeof(yaffs_CheckpointObject) + sizeof(__u32)) * (dev->nObjectsCreated - dev->nFreeObjects);
+		nBytes += (tnodeSize + sizeof(__u32)) * (dev->nTnodesCreated - dev->nFreeTnodes);
+		nBytes += sizeof(yaffs_CheckpointValidity);
+		nBytes += sizeof(__u32); /* checksum*/
+
+		/* Round up and add 2 blocks to allow for some bad blocks, so add 3 */
+
+		nBlocks = (nBytes/(dev->nDataBytesPerChunk * dev->param.nChunksPerBlock)) + 3;
+
+		dev->nCheckpointBlocksRequired = nBlocks;
+	}
+
+	return dev->nCheckpointBlocksRequired;
+}
+
+/*
+ * Check if there's space to allocate...
+ * Thinks.... do we need top make this ths same as yaffs_GetFreeChunks()?
+ */
+static int yaffs_CheckSpaceForAllocation(yaffs_Device *dev, int nChunks)
+{
+	int reservedChunks;
+	int reservedBlocks = dev->param.nReservedBlocks;
+	int checkpointBlocks;
+
+	if (dev->param.isYaffs2) {
+		checkpointBlocks =  yaffs_CalcCheckpointBlocksRequired(dev) -
+				    dev->blocksInCheckpoint;
+		if (checkpointBlocks < 0)
+			checkpointBlocks = 0;
+	} else {
+		checkpointBlocks = 0;
+	}
+
+	reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->param.nChunksPerBlock);
+
+	return (dev->nFreeChunks > (reservedChunks + nChunks));
+}
+
+static int yaffs_AllocateChunk(yaffs_Device *dev, int useReserve,
+		yaffs_BlockInfo **blockUsedPtr)
+{
+	int retVal;
+	yaffs_BlockInfo *bi;
+
+	if (dev->allocationBlock < 0) {
+		/* Get next block to allocate off */
+		dev->allocationBlock = yaffs_FindBlockForAllocation(dev);
+		dev->allocationPage = 0;
+	}
+
+	if (!useReserve && !yaffs_CheckSpaceForAllocation(dev, 1)) {
+		/* Not enough space to allocate unless we're allowed to use the reserve. */
+		return -1;
+	}
+
+	if (dev->nErasedBlocks < dev->param.nReservedBlocks
+			&& dev->allocationPage == 0) {
+		T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
+	}
+
+	/* Next page please.... */
+	if (dev->allocationBlock >= 0) {
+		bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
+
+		retVal = (dev->allocationBlock * dev->param.nChunksPerBlock) +
+			dev->allocationPage;
+		bi->pagesInUse++;
+		yaffs_SetChunkBit(dev, dev->allocationBlock,
+				dev->allocationPage);
+
+		dev->allocationPage++;
+
+		dev->nFreeChunks--;
+
+		/* If the block is full set the state to full */
+		if (dev->allocationPage >= dev->param.nChunksPerBlock) {
+			bi->blockState = YAFFS_BLOCK_STATE_FULL;
+			dev->allocationBlock = -1;
+		}
+
+		if (blockUsedPtr)
+			*blockUsedPtr = bi;
+
+		return retVal;
+	}
+
+	T(YAFFS_TRACE_ERROR,
+			(TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
+
+	return -1;
+}
+
+static int yaffs_GetErasedChunks(yaffs_Device *dev)
+{
+	int n;
+
+	n = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+
+	if (dev->allocationBlock > 0)
+		n += (dev->param.nChunksPerBlock - dev->allocationPage);
+
+	return n;
+
+}
+
+/*
+ * yaffs_SkipRestOfBlock() skips over the rest of the allocation block
+ * if we don't want to write to it.
+ */
+static void yaffs_SkipRestOfBlock(yaffs_Device *dev)
+{
+	if(dev->allocationBlock > 0){
+		yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
+		if(bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING){
+			bi->blockState = YAFFS_BLOCK_STATE_FULL;
+			dev->allocationBlock = -1;
+		}
+	}
+}
+
+
+static int yaffs_GarbageCollectBlock(yaffs_Device *dev, int block,
+		int wholeBlock)
+{
+	int oldChunk;
+	int newChunk;
+	int markNAND;
+	int retVal = YAFFS_OK;
+	int cleanups = 0;
+	int i;
+	int isCheckpointBlock;
+	int matchingChunk;
+	int maxCopies;
+
+	int chunksBefore = yaffs_GetErasedChunks(dev);
+	int chunksAfter;
+
+	yaffs_ExtendedTags tags;
+
+	yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, block);
+
+	yaffs_Object *object;
+
+	isCheckpointBlock = (bi->blockState == YAFFS_BLOCK_STATE_CHECKPOINT);
+
+
+	T(YAFFS_TRACE_TRACING,
+			(TSTR("Collecting block %d, in use %d, shrink %d, wholeBlock %d" TENDSTR),
+			 block,
+			 bi->pagesInUse,
+			 bi->hasShrinkHeader,
+			 wholeBlock));
+
+	/*yaffs_VerifyFreeChunks(dev); */
+
+	if(bi->blockState == YAFFS_BLOCK_STATE_FULL)
+		bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
+	
+	bi->hasShrinkHeader = 0;	/* clear the flag so that the block can erase */
+
+	dev->gcDisable = 1;
+
+	if (isCheckpointBlock ||
+			!yaffs_StillSomeChunkBits(dev, block)) {
+		T(YAFFS_TRACE_TRACING,
+				(TSTR
+				 ("Collecting block %d that has no chunks in use" TENDSTR),
+				 block));
+		yaffs_BlockBecameDirty(dev, block);
+	} else {
+
+		__u8 *buffer = yaffs_GetTempBuffer(dev, __LINE__);
+
+		yaffs_VerifyBlock(dev, bi, block);
+
+		maxCopies = (wholeBlock) ? dev->param.nChunksPerBlock : 5;
+		oldChunk = block * dev->param.nChunksPerBlock + dev->gcChunk;
+
+		for (/* init already done */;
+		     retVal == YAFFS_OK &&
+		     dev->gcChunk < dev->param.nChunksPerBlock &&
+		     (bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) &&
+		     maxCopies > 0;
+		     dev->gcChunk++, oldChunk++) {
+			if (yaffs_CheckChunkBit(dev, block, dev->gcChunk)) {
+
+				/* This page is in use and might need to be copied off */
+
+				maxCopies--;
+
+				markNAND = 1;
+
+				yaffs_InitialiseTags(&tags);
+
+				yaffs_ReadChunkWithTagsFromNAND(dev, oldChunk,
+								buffer, &tags);
+
+				object =
+				    yaffs_FindObjectByNumber(dev,
+							     tags.objectId);
+
+				T(YAFFS_TRACE_GC_DETAIL,
+				  (TSTR
+				   ("Collecting chunk in block %d, %d %d %d " TENDSTR),
+				   dev->gcChunk, tags.objectId, tags.chunkId,
+				   tags.byteCount));
+
+				if (object && !yaffs_SkipVerification(dev)) {
+					if (tags.chunkId == 0)
+						matchingChunk = object->hdrChunk;
+					else if (object->softDeleted)
+						matchingChunk = oldChunk; /* Defeat the test */
+					else
+						matchingChunk = yaffs_FindChunkInFile(object, tags.chunkId, NULL);
+
+					if (oldChunk != matchingChunk)
+						T(YAFFS_TRACE_ERROR,
+						  (TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
+						  oldChunk, matchingChunk, tags.objectId, tags.chunkId));
+
+				}
+
+				if (!object) {
+					T(YAFFS_TRACE_ERROR,
+					  (TSTR
+					   ("page %d in gc has no object: %d %d %d "
+					    TENDSTR), oldChunk,
+					    tags.objectId, tags.chunkId, tags.byteCount));
+				}
+
+				if (object &&
+				    object->deleted &&
+				    object->softDeleted &&
+				    tags.chunkId != 0) {
+					/* Data chunk in a soft deleted file, throw it away
+					 * It's a soft deleted data chunk,
+					 * No need to copy this, just forget about it and
+					 * fix up the object.
+					 */
+					 
+					/* Free chunks already includes softdeleted chunks.
+					 * How ever this chunk is going to soon be really deleted
+					 * which will increment free chunks.
+					 * We have to decrement free chunks so this works out properly.
+					 */
+					dev->nFreeChunks--;
+
+					object->nDataChunks--;
+
+					if (object->nDataChunks <= 0) {
+						/* remeber to clean up the object */
+						dev->gcCleanupList[cleanups] =
+						    tags.objectId;
+						cleanups++;
+					}
+					markNAND = 0;
+				} else if (0) {
+					/* Todo object && object->deleted && object->nDataChunks == 0 */
+					/* Deleted object header with no data chunks.
+					 * Can be discarded and the file deleted.
+					 */
+					object->hdrChunk = 0;
+					yaffs_FreeTnode(object->myDev,
+							object->variant.
+							fileVariant.top);
+					object->variant.fileVariant.top = NULL;
+					yaffs_DoGenericObjectDeletion(object);
+
+				} else if (object) {
+					/* It's either a data chunk in a live file or
+					 * an ObjectHeader, so we're interested in it.
+					 * NB Need to keep the ObjectHeaders of deleted files
+					 * until the whole file has been deleted off
+					 */
+					tags.serialNumber++;
+
+					dev->nGCCopies++;
+
+					if (tags.chunkId == 0) {
+						/* It is an object Id,
+						 * We need to nuke the shrinkheader flags first
+						 * Also need to clean up shadowing.
+						 * We no longer want the shrinkHeader flag since its work is done
+						 * and if it is left in place it will mess up scanning.
+						 */
+
+						yaffs_ObjectHeader *oh;
+						oh = (yaffs_ObjectHeader *)buffer;
+
+						oh->isShrink = 0;
+						tags.extraIsShrinkHeader = 0;
+
+						oh->shadowsObject = 0;
+						oh->inbandShadowsObject = 0;
+						tags.extraShadows = 0;
+
+						/* Update file size */
+						if(object->variantType == YAFFS_OBJECT_TYPE_FILE){
+							oh->fileSize = object->variant.fileVariant.fileSize;
+							tags.extraFileLength = oh->fileSize;
+						}
+
+						yaffs_VerifyObjectHeader(object, oh, &tags, 1);
+						newChunk =
+						    yaffs_WriteNewChunkWithTagsToNAND(dev,(__u8 *) oh, &tags, 1);
+					} else
+						newChunk =
+						    yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &tags, 1);
+
+					if (newChunk < 0) {
+						retVal = YAFFS_FAIL;
+					} else {
+
+						/* Ok, now fix up the Tnodes etc. */
+
+						if (tags.chunkId == 0) {
+							/* It's a header */
+							object->hdrChunk =  newChunk;
+							object->serial =   tags.serialNumber;
+						} else {
+							/* It's a data chunk */
+							int ok;
+							ok = yaffs_PutChunkIntoFile
+							    (object,
+							     tags.chunkId,
+							     newChunk, 0);
+						}
+					}
+				}
+
+				if (retVal == YAFFS_OK)
+					yaffs_DeleteChunk(dev, oldChunk, markNAND, __LINE__);
+
+			}
+		}
+
+		yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+
+
+		/* Do any required cleanups */
+		for (i = 0; i < cleanups; i++) {
+			/* Time to delete the file too */
+			object =
+			    yaffs_FindObjectByNumber(dev,
+						     dev->gcCleanupList[i]);
+			if (object) {
+				yaffs_FreeTnode(dev,
+						object->variant.fileVariant.
+						top);
+				object->variant.fileVariant.top = NULL;
+				T(YAFFS_TRACE_GC,
+				  (TSTR
+				   ("yaffs: About to finally delete object %d"
+				    TENDSTR), object->objectId));
+				yaffs_DoGenericObjectDeletion(object);
+				object->myDev->nDeletedFiles--;
+			}
+
+		}
+
+	}
+
+	yaffs_VerifyCollectedBlock(dev, bi, block);
+
+
+
+	if (bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
+		/*
+		 * The gc did not complete. Set block state back to FULL
+		 * because checkpointing does not restore gc.
+		 */
+		bi->blockState = YAFFS_BLOCK_STATE_FULL;
+	} else {
+		/* The gc completed. */
+		chunksAfter = yaffs_GetErasedChunks(dev);
+		if (chunksBefore >= chunksAfter) {
+			T(YAFFS_TRACE_GC,
+			  (TSTR
+			   ("gc did not increase free chunks before %d after %d"
+			    TENDSTR), chunksBefore, chunksAfter));
+		}
+		dev->gcBlock = 0;
+		dev->gcChunk = 0;
+	}
+
+	dev->gcDisable = 0;
+
+	return retVal;
+}
+
+/*
+ * FindBlockForgarbageCollection is used to select the dirtiest block (or close enough)
+ * for garbage collection.
+ */
+
+static unsigned yaffs_FindBlockForGarbageCollection(yaffs_Device *dev,
+					int aggressive,
+					int background)
+{
+	int i;
+	int iterations;
+	unsigned selected = 0;
+	int prioritised = 0;
+	int prioritisedExists = 0;
+	yaffs_BlockInfo *bi;
+	int threshold;
+
+	/* First let's see if we need to grab a prioritised block */
+	if (dev->hasPendingPrioritisedGCs && !aggressive) {
+		dev->gcDirtiest = 0;
+		bi = dev->blockInfo;
+		for (i = dev->internalStartBlock;
+			i <= dev->internalEndBlock && !selected;
+			i++) {
+
+			if (bi->gcPrioritise) {
+				prioritisedExists = 1;
+				if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
+				   yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
+					selected = i;
+					prioritised = 1;
+				}
+			}
+			bi++;
+		}
+
+		/*
+		 * If there is a prioritised block and none was selected then
+		 * this happened because there is at least one old dirty block gumming
+		 * up the works. Let's gc the oldest dirty block.
+		 */
+
+		if(prioritisedExists &&
+			!selected &&
+			dev->oldestDirtyBlock > 0)
+			selected = dev->oldestDirtyBlock;
+
+		if (!prioritisedExists) /* None found, so we can clear this */
+			dev->hasPendingPrioritisedGCs = 0;
+	}
+
+	/* If we're doing aggressive GC then we are happy to take a less-dirty block, and
+	 * search harder.
+	 * else (we're doing a leasurely gc), then we only bother to do this if the
+	 * block has only a few pages in use.
+	 */
+
+	if (!selected){
+		int pagesUsed;
+		int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
+		if (aggressive){
+			threshold = dev->param.nChunksPerBlock;
+			iterations = nBlocks;
+		} else {
+			int maxThreshold = dev->param.nChunksPerBlock/2;
+			threshold = background ?
+				(dev->gcNotDone + 2) * 2 : 0;
+			if(threshold <YAFFS_GC_PASSIVE_THRESHOLD)
+				threshold = YAFFS_GC_PASSIVE_THRESHOLD;
+			if(threshold > maxThreshold)
+				threshold = maxThreshold;
+
+			iterations = nBlocks / 16 + 1;
+			if (iterations > 100)
+				iterations = 100;
+		}
+
+		for (i = 0;
+			i < iterations &&
+			(dev->gcDirtiest < 1 ||
+				dev->gcPagesInUse > YAFFS_GC_GOOD_ENOUGH);
+			i++) {
+			dev->gcBlockFinder++;
+			if (dev->gcBlockFinder < dev->internalStartBlock ||
+				dev->gcBlockFinder > dev->internalEndBlock)
+				dev->gcBlockFinder = dev->internalStartBlock;
+
+			bi = yaffs_GetBlockInfo(dev, dev->gcBlockFinder);
+
+			pagesUsed = bi->pagesInUse - bi->softDeletions;
+
+			if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
+				pagesUsed < dev->param.nChunksPerBlock &&
+				(dev->gcDirtiest < 1 || pagesUsed < dev->gcPagesInUse) &&
+				yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
+				dev->gcDirtiest = dev->gcBlockFinder;
+				dev->gcPagesInUse = pagesUsed;
+			}
+		}
+
+		if(dev->gcDirtiest > 0 && dev->gcPagesInUse <= threshold)
+			selected = dev->gcDirtiest;
+	}
+
+	/*
+	 * If nothing has been selected for a while, try selecting the oldest dirty
+	 * because that's gumming up the works.
+	 */
+
+	if(!selected && dev->param.isYaffs2 &&
+		dev->gcNotDone >= ( background ? 10 : 20)){
+		yaffs_FindOldestDirtySequence(dev);
+		if(dev->oldestDirtyBlock > 0) {
+			selected = dev->oldestDirtyBlock;
+			dev->gcDirtiest = selected;
+			dev->oldestDirtyGCs++;
+			bi = yaffs_GetBlockInfo(dev, selected);
+			dev->gcPagesInUse =  bi->pagesInUse - bi->softDeletions;
+		} else
+			dev->gcNotDone = 0;
+	}
+
+	if(selected){
+		T(YAFFS_TRACE_GC,
+		  (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR),
+		  selected,
+		  dev->param.nChunksPerBlock - dev->gcPagesInUse,
+		  prioritised));
+
+		if(background)
+			dev->backgroundGCs++;
+		dev->gcDirtiest = 0;
+		dev->gcPagesInUse = 0;
+		dev->gcNotDone = 0;
+		if(dev->refreshSkip > 0)
+			dev->refreshSkip--;
+	} else{
+		dev->gcNotDone++;
+		T(YAFFS_TRACE_GC,
+		  (TSTR("GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s" TENDSTR),
+		  dev->gcBlockFinder, dev->gcNotDone,
+		  threshold,
+		  dev->gcDirtiest, dev->gcPagesInUse,
+		  dev->oldestDirtyBlock,
+		  background ? " bg" : ""));
+	}
+
+	return selected;
+}
+
+/* New garbage collector
+ * If we're very low on erased blocks then we do aggressive garbage collection
+ * otherwise we do "leasurely" garbage collection.
+ * Aggressive gc looks further (whole array) and will accept less dirty blocks.
+ * Passive gc only inspects smaller areas and will only accept more dirty blocks.
+ *
+ * The idea is to help clear out space in a more spread-out manner.
+ * Dunno if it really does anything useful.
+ */
+static int yaffs_CheckGarbageCollection(yaffs_Device *dev, int background)
+{
+	int aggressive = 0;
+	int gcOk = YAFFS_OK;
+	int maxTries = 0;
+
+	int minErased;
+	int erasedChunks;
+
+	int checkpointBlockAdjust;
+
+	if(dev->param.gcControl &&
+		(dev->param.gcControl(dev) & 1) == 0)
+		return YAFFS_OK;
+
+	if (dev->gcDisable) {
+		/* Bail out so we don't get recursive gc */
+		return YAFFS_OK;
+	}
+
+	/* This loop should pass the first time.
+	 * We'll only see looping here if the collection does not increase space.
+	 */
+
+	do {
+		maxTries++;
+
+		checkpointBlockAdjust = yaffs_CalcCheckpointBlocksRequired(dev) - dev->blocksInCheckpoint;
+		if (checkpointBlockAdjust < 0)
+			checkpointBlockAdjust = 0;
+
+		minErased  = dev->param.nReservedBlocks + checkpointBlockAdjust + 1;
+		erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+
+		/* If we need a block soon then do aggressive gc.*/
+		if (dev->nErasedBlocks < minErased)
+			aggressive = 1;
+		else {
+			if(dev->gcSkip > 20)
+				dev->gcSkip = 20;
+			if(erasedChunks < dev->nFreeChunks/2 ||
+				dev->gcSkip < 1 ||
+				background)
+				aggressive = 0;
+			else {
+				dev->gcSkip--;
+				break;
+			}
+		}
+
+		dev->gcSkip = 5;
+
+                /* If we don't already have a block being gc'd then see if we should start another */
+
+		if (dev->gcBlock < 1 && !aggressive) {
+			dev->gcBlock = yaffs_FindRefreshBlock(dev);
+			dev->gcChunk = 0;
+		}
+		if (dev->gcBlock < 1) {
+			dev->gcBlock = yaffs_FindBlockForGarbageCollection(dev, aggressive, background);
+			dev->gcChunk = 0;
+		}
+
+		if (dev->gcBlock > 0) {
+			dev->allGCs++;
+			if (!aggressive)
+				dev->passiveGCs++;
+
+			T(YAFFS_TRACE_GC,
+			  (TSTR
+			   ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
+			   dev->nErasedBlocks, aggressive));
+
+			gcOk = yaffs_GarbageCollectBlock(dev, dev->gcBlock, aggressive);
+		}
+
+		if (dev->nErasedBlocks < (dev->param.nReservedBlocks) && dev->gcBlock > 0) {
+			T(YAFFS_TRACE_GC,
+			  (TSTR
+			   ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
+			    TENDSTR), dev->nErasedBlocks, maxTries, dev->gcBlock));
+		}
+	} while ((dev->nErasedBlocks < dev->param.nReservedBlocks) &&
+		 (dev->gcBlock > 0) &&
+		 (maxTries < 2));
+
+	return aggressive ? gcOk : YAFFS_OK;
+}
+
+/*
+ * yaffs_BackgroundGarbageCollect()
+ * Garbage collects. Intended to be called from a background thread.
+ * Returns non-zero if at least half the free chunks are erased.
+ */
+int yaffs_BackgroundGarbageCollect(yaffs_Device *dev, unsigned urgency)
+{
+	int erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+
+	T(YAFFS_TRACE_BACKGROUND, (TSTR("Background gc %u" TENDSTR),urgency));
+
+	yaffs_CheckGarbageCollection(dev, 1);
+	return erasedChunks > dev->nFreeChunks/2;
+}
+
+/*-------------------------  TAGS --------------------------------*/
+
+static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId,
+			   int chunkInObject)
+{
+	return (tags->chunkId == chunkInObject &&
+		tags->objectId == objectId && !tags->chunkDeleted) ? 1 : 0;
+
+}
+
+
+/*-------------------- Data file manipulation -----------------*/
+
+static int yaffs_FindChunkInFile(yaffs_Object *in, int chunkInInode,
+				 yaffs_ExtendedTags *tags)
+{
+	/*Get the Tnode, then get the level 0 offset chunk offset */
+	yaffs_Tnode *tn;
+	int theChunk = -1;
+	yaffs_ExtendedTags localTags;
+	int retVal = -1;
+
+	yaffs_Device *dev = in->myDev;
+
+	if (!tags) {
+		/* Passed a NULL, so use our own tags space */
+		tags = &localTags;
+	}
+
+	tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
+
+	if (tn) {
+		theChunk = yaffs_GetChunkGroupBase(dev, tn, chunkInInode);
+
+		retVal =
+		    yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
+					   chunkInInode);
+	}
+	return retVal;
+}
+
+static int yaffs_FindAndDeleteChunkInFile(yaffs_Object *in, int chunkInInode,
+					  yaffs_ExtendedTags *tags)
+{
+	/* Get the Tnode, then get the level 0 offset chunk offset */
+	yaffs_Tnode *tn;
+	int theChunk = -1;
+	yaffs_ExtendedTags localTags;
+
+	yaffs_Device *dev = in->myDev;
+	int retVal = -1;
+
+	if (!tags) {
+		/* Passed a NULL, so use our own tags space */
+		tags = &localTags;
+	}
+
+	tn = yaffs_FindLevel0Tnode(dev, &in->variant.fileVariant, chunkInInode);
+
+	if (tn) {
+
+		theChunk = yaffs_GetChunkGroupBase(dev, tn, chunkInInode);
+
+		retVal =
+		    yaffs_FindChunkInGroup(dev, theChunk, tags, in->objectId,
+					   chunkInInode);
+
+		/* Delete the entry in the filestructure (if found) */
+		if (retVal != -1)
+			yaffs_LoadLevel0Tnode(dev, tn, chunkInInode, 0);
+	}
+
+	return retVal;
+}
+
+#ifdef YAFFS_PARANOID
+
+static int yaffs_CheckFileSanity(yaffs_Object *in)
+{
+	int chunk;
+	int nChunks;
+	int fSize;
+	int failed = 0;
+	int objId;
+	yaffs_Tnode *tn;
+	yaffs_Tags localTags;
+	yaffs_Tags *tags = &localTags;
+	int theChunk;
+	int chunkDeleted;
+
+	if (in->variantType != YAFFS_OBJECT_TYPE_FILE)
+		return YAFFS_FAIL;
+
+	objId = in->objectId;
+	fSize = in->variant.fileVariant.fileSize;
+	nChunks =
+	    (fSize + in->myDev->nDataBytesPerChunk - 1) / in->myDev->nDataBytesPerChunk;
+
+	for (chunk = 1; chunk <= nChunks; chunk++) {
+		tn = yaffs_FindLevel0Tnode(in->myDev, &in->variant.fileVariant,
+					   chunk);
+
+		if (tn) {
+
+			theChunk = yaffs_GetChunkGroupBase(dev, tn, chunk);
+
+			if (yaffs_CheckChunkBits
+			    (dev, theChunk / dev->param.nChunksPerBlock,
+			     theChunk % dev->param.nChunksPerBlock)) {
+
+				yaffs_ReadChunkTagsFromNAND(in->myDev, theChunk,
+							    tags,
+							    &chunkDeleted);
+				if (yaffs_TagsMatch
+				    (tags, in->objectId, chunk, chunkDeleted)) {
+					/* found it; */
+
+				}
+			} else {
+
+				failed = 1;
+			}
+
+		} else {
+			/* T(("No level 0 found for %d\n", chunk)); */
+		}
+	}
+
+	return failed ? YAFFS_FAIL : YAFFS_OK;
+}
+
+#endif
+
+static int yaffs_PutChunkIntoFile(yaffs_Object *in, int chunkInInode,
+				  int chunkInNAND, int inScan)
+{
+	/* NB inScan is zero unless scanning.
+	 * For forward scanning, inScan is > 0;
+	 * for backward scanning inScan is < 0
+	 *
+	 * chunkInNAND = 0 is a dummy insert to make sure the tnodes are there.
+	 */
+
+	yaffs_Tnode *tn;
+	yaffs_Device *dev = in->myDev;
+	int existingChunk;
+	yaffs_ExtendedTags existingTags;
+	yaffs_ExtendedTags newTags;
+	unsigned existingSerial, newSerial;
+
+	if (in->variantType != YAFFS_OBJECT_TYPE_FILE) {
+		/* Just ignore an attempt at putting a chunk into a non-file during scanning
+		 * If it is not during Scanning then something went wrong!
+		 */
+		if (!inScan) {
+			T(YAFFS_TRACE_ERROR,
+			  (TSTR
+			   ("yaffs tragedy:attempt to put data chunk into a non-file"
+			    TENDSTR)));
+			YBUG();
+		}
+
+		yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
+		return YAFFS_OK;
+	}
+
+	tn = yaffs_AddOrFindLevel0Tnode(dev,
+					&in->variant.fileVariant,
+					chunkInInode,
+					NULL);
+	if (!tn)
+		return YAFFS_FAIL;
+	
+	if(!chunkInNAND)
+		/* Dummy insert, bail now */
+		return YAFFS_OK;
+
+	existingChunk = yaffs_GetChunkGroupBase(dev, tn, chunkInInode);
+
+	if (inScan != 0) {
+		/* If we're scanning then we need to test for duplicates
+		 * NB This does not need to be efficient since it should only ever
+		 * happen when the power fails during a write, then only one
+		 * chunk should ever be affected.
+		 *
+		 * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
+		 * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
+		 */
+
+		if (existingChunk > 0) {
+			/* NB Right now existing chunk will not be real chunkId if the device >= 32MB
+			 *    thus we have to do a FindChunkInFile to get the real chunk id.
+			 *
+			 * We have a duplicate now we need to decide which one to use:
+			 *
+			 * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
+			 * Forward scanning YAFFS2: The new one is what we use, dump the old one.
+			 * YAFFS1: Get both sets of tags and compare serial numbers.
+			 */
+
+			if (inScan > 0) {
+				/* Only do this for forward scanning */
+				yaffs_ReadChunkWithTagsFromNAND(dev,
+								chunkInNAND,
+								NULL, &newTags);
+
+				/* Do a proper find */
+				existingChunk =
+				    yaffs_FindChunkInFile(in, chunkInInode,
+							  &existingTags);
+			}
+
+			if (existingChunk <= 0) {
+				/*Hoosterman - how did this happen? */
+
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("yaffs tragedy: existing chunk < 0 in scan"
+				    TENDSTR)));
+
+			}
+
+			/* NB The deleted flags should be false, otherwise the chunks will
+			 * not be loaded during a scan
+			 */
+
+			if (inScan > 0) {
+				newSerial = newTags.serialNumber;
+				existingSerial = existingTags.serialNumber;
+			}
+
+			if ((inScan > 0) &&
+			    (in->myDev->param.isYaffs2 ||
+			     existingChunk <= 0 ||
+			     ((existingSerial + 1) & 3) == newSerial)) {
+				/* Forward scanning.
+				 * Use new
+				 * Delete the old one and drop through to update the tnode
+				 */
+				yaffs_DeleteChunk(dev, existingChunk, 1,
+						  __LINE__);
+			} else {
+				/* Backward scanning or we want to use the existing one
+				 * Use existing.
+				 * Delete the new one and return early so that the tnode isn't changed
+				 */
+				yaffs_DeleteChunk(dev, chunkInNAND, 1,
+						  __LINE__);
+				return YAFFS_OK;
+			}
+		}
+
+	}
+
+	if (existingChunk == 0)
+		in->nDataChunks++;
+
+	yaffs_LoadLevel0Tnode(dev, tn, chunkInInode, chunkInNAND);
+
+	return YAFFS_OK;
+}
+
+static int yaffs_ReadChunkDataFromObject(yaffs_Object *in, int chunkInInode,
+					__u8 *buffer)
+{
+	int chunkInNAND = yaffs_FindChunkInFile(in, chunkInInode, NULL);
+
+	if (chunkInNAND >= 0)
+		return yaffs_ReadChunkWithTagsFromNAND(in->myDev, chunkInNAND,
+						buffer, NULL);
+	else {
+		T(YAFFS_TRACE_NANDACCESS,
+		  (TSTR("Chunk %d not found zero instead" TENDSTR),
+		   chunkInNAND));
+		/* get sane (zero) data if you read a hole */
+		memset(buffer, 0, in->myDev->nDataBytesPerChunk);
+		return 0;
+	}
+
+}
+
+void yaffs_DeleteChunk(yaffs_Device *dev, int chunkId, int markNAND, int lyn)
+{
+	int block;
+	int page;
+	yaffs_ExtendedTags tags;
+	yaffs_BlockInfo *bi;
+
+	if (chunkId <= 0)
+		return;
+
+	dev->nDeletions++;
+	block = chunkId / dev->param.nChunksPerBlock;
+	page = chunkId % dev->param.nChunksPerBlock;
+
+
+	if (!yaffs_CheckChunkBit(dev, block, page))
+		T(YAFFS_TRACE_VERIFY,
+			(TSTR("Deleting invalid chunk %d"TENDSTR),
+			 chunkId));
+
+	bi = yaffs_GetBlockInfo(dev, block);
+	
+	yaffs_UpdateOldestDirtySequence(dev, block, bi);
+
+	T(YAFFS_TRACE_DELETION,
+	  (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunkId));
+
+	if (markNAND &&
+	    bi->blockState != YAFFS_BLOCK_STATE_COLLECTING && !dev->param.isYaffs2) {
+
+		yaffs_InitialiseTags(&tags);
+
+		tags.chunkDeleted = 1;
+
+		yaffs_WriteChunkWithTagsToNAND(dev, chunkId, NULL, &tags);
+		yaffs_HandleUpdateChunk(dev, chunkId, &tags);
+	} else {
+		dev->nUnmarkedDeletions++;
+	}
+
+	/* Pull out of the management area.
+	 * If the whole block became dirty, this will kick off an erasure.
+	 */
+	if (bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING ||
+	    bi->blockState == YAFFS_BLOCK_STATE_FULL ||
+	    bi->blockState == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
+	    bi->blockState == YAFFS_BLOCK_STATE_COLLECTING) {
+		dev->nFreeChunks++;
+
+		yaffs_ClearChunkBit(dev, block, page);
+
+		bi->pagesInUse--;
+
+		if (bi->pagesInUse == 0 &&
+		    !bi->hasShrinkHeader &&
+		    bi->blockState != YAFFS_BLOCK_STATE_ALLOCATING &&
+		    bi->blockState != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+			yaffs_BlockBecameDirty(dev, block);
+		}
+
+	}
+
+}
+
+static int yaffs_WriteChunkDataToObject(yaffs_Object *in, int chunkInInode,
+					const __u8 *buffer, int nBytes,
+					int useReserve)
+{
+	/* Find old chunk Need to do this to get serial number
+	 * Write new one and patch into tree.
+	 * Invalidate old tags.
+	 */
+
+	int prevChunkId;
+	yaffs_ExtendedTags prevTags;
+
+	int newChunkId;
+	yaffs_ExtendedTags newTags;
+
+	yaffs_Device *dev = in->myDev;
+
+	yaffs_CheckGarbageCollection(dev,0);
+
+	/* Get the previous chunk at this location in the file if it exists.
+	 * If it does not exist then put a zero into the tree. This creates
+	 * the tnode now, rather than later when it is harder to clean up.
+	 */
+	prevChunkId = yaffs_FindChunkInFile(in, chunkInInode, &prevTags);
+	if(prevChunkId < 1 &&
+		!yaffs_PutChunkIntoFile(in, chunkInInode, 0, 0))
+		return 0;
+
+	/* Set up new tags */
+	yaffs_InitialiseTags(&newTags);
+
+	newTags.chunkId = chunkInInode;
+	newTags.objectId = in->objectId;
+	newTags.serialNumber =
+	    (prevChunkId > 0) ? prevTags.serialNumber + 1 : 1;
+	newTags.byteCount = nBytes;
+
+	if (nBytes < 1 || nBytes > dev->param.totalBytesPerChunk) {
+		T(YAFFS_TRACE_ERROR,
+		(TSTR("Writing %d bytes to chunk!!!!!!!!!" TENDSTR), nBytes));
+		YBUG();
+	}
+	
+		
+	newChunkId =
+	    yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
+					      useReserve);
+
+	if (newChunkId > 0) {
+		yaffs_PutChunkIntoFile(in, chunkInInode, newChunkId, 0);
+
+		if (prevChunkId > 0)
+			yaffs_DeleteChunk(dev, prevChunkId, 1, __LINE__);
+
+		yaffs_CheckFileSanity(in);
+	}
+	return newChunkId;
+
+}
+
+/* UpdateObjectHeader updates the header on NAND for an object.
+ * If name is not NULL, then that new name is used.
+ */
+int yaffs_UpdateObjectHeader(yaffs_Object *in, const YCHAR *name, int force,
+			     int isShrink, int shadows)
+{
+
+	yaffs_BlockInfo *bi;
+
+	yaffs_Device *dev = in->myDev;
+
+	int prevChunkId;
+	int retVal = 0;
+	int result = 0;
+
+	int newChunkId;
+	yaffs_ExtendedTags newTags;
+	yaffs_ExtendedTags oldTags;
+	YCHAR *alias = NULL;
+
+	__u8 *buffer = NULL;
+	YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
+
+	yaffs_ObjectHeader *oh = NULL;
+
+	yaffs_strcpy(oldName, _Y("silly old name"));
+
+
+	if (!in->fake ||
+		in == dev->rootDir || /* The rootDir should also be saved */
+		force) {
+
+		yaffs_CheckGarbageCollection(dev,0);
+		yaffs_CheckObjectDetailsLoaded(in);
+
+		buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
+		oh = (yaffs_ObjectHeader *) buffer;
+
+		prevChunkId = in->hdrChunk;
+
+		if (prevChunkId > 0) {
+			result = yaffs_ReadChunkWithTagsFromNAND(dev, prevChunkId,
+							buffer, &oldTags);
+
+			yaffs_VerifyObjectHeader(in, oh, &oldTags, 0);
+
+			memcpy(oldName, oh->name, sizeof(oh->name));
+		}
+
+		memset(buffer, 0xFF, dev->nDataBytesPerChunk);
+
+		oh->type = in->variantType;
+		oh->yst_mode = in->yst_mode;
+		oh->shadowsObject = oh->inbandShadowsObject = shadows;
+
+#ifdef CONFIG_YAFFS_WINCE
+		oh->win_atime[0] = in->win_atime[0];
+		oh->win_ctime[0] = in->win_ctime[0];
+		oh->win_mtime[0] = in->win_mtime[0];
+		oh->win_atime[1] = in->win_atime[1];
+		oh->win_ctime[1] = in->win_ctime[1];
+		oh->win_mtime[1] = in->win_mtime[1];
+#else
+		oh->yst_uid = in->yst_uid;
+		oh->yst_gid = in->yst_gid;
+		oh->yst_atime = in->yst_atime;
+		oh->yst_mtime = in->yst_mtime;
+		oh->yst_ctime = in->yst_ctime;
+		oh->yst_rdev = in->yst_rdev;
+#endif
+		if (in->parent)
+			oh->parentObjectId = in->parent->objectId;
+		else
+			oh->parentObjectId = 0;
+
+		if (name && *name) {
+			memset(oh->name, 0, sizeof(oh->name));
+			yaffs_strncpy(oh->name, name, YAFFS_MAX_NAME_LENGTH);
+		} else if (prevChunkId > 0)
+			memcpy(oh->name, oldName, sizeof(oh->name));
+		else
+			memset(oh->name, 0, sizeof(oh->name));
+
+		oh->isShrink = isShrink;
+
+		switch (in->variantType) {
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+			/* Should not happen */
+			break;
+		case YAFFS_OBJECT_TYPE_FILE:
+			oh->fileSize =
+			    (oh->parentObjectId == YAFFS_OBJECTID_DELETED
+			     || oh->parentObjectId ==
+			     YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
+			    fileVariant.fileSize;
+			break;
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+			oh->equivalentObjectId =
+			    in->variant.hardLinkVariant.equivalentObjectId;
+			break;
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+			/* Do nothing */
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			/* Do nothing */
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			alias = in->variant.symLinkVariant.alias;
+			if(!alias)
+				alias = _Y("no alias");
+			yaffs_strncpy(oh->alias,
+					alias,
+				      YAFFS_MAX_ALIAS_LENGTH);
+			oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
+			break;
+		}
+
+		/* Tags */
+		yaffs_InitialiseTags(&newTags);
+		in->serial++;
+		newTags.chunkId = 0;
+		newTags.objectId = in->objectId;
+		newTags.serialNumber = in->serial;
+
+		/* Add extra info for file header */
+
+		newTags.extraHeaderInfoAvailable = 1;
+		newTags.extraParentObjectId = oh->parentObjectId;
+		newTags.extraFileLength = oh->fileSize;
+		newTags.extraIsShrinkHeader = oh->isShrink;
+		newTags.extraEquivalentObjectId = oh->equivalentObjectId;
+		newTags.extraShadows = (oh->shadowsObject > 0) ? 1 : 0;
+		newTags.extraObjectType = in->variantType;
+
+		yaffs_VerifyObjectHeader(in, oh, &newTags, 1);
+
+		/* Create new chunk in NAND */
+		newChunkId =
+		    yaffs_WriteNewChunkWithTagsToNAND(dev, buffer, &newTags,
+						      (prevChunkId > 0) ? 1 : 0);
+
+		if (newChunkId >= 0) {
+
+			in->hdrChunk = newChunkId;
+
+			if (prevChunkId > 0) {
+				yaffs_DeleteChunk(dev, prevChunkId, 1,
+						  __LINE__);
+			}
+
+			if (!yaffs_ObjectHasCachedWriteData(in))
+				in->dirty = 0;
+
+			/* If this was a shrink, then mark the block that the chunk lives on */
+			if (isShrink) {
+				bi = yaffs_GetBlockInfo(in->myDev,
+					newChunkId / in->myDev->param.nChunksPerBlock);
+				bi->hasShrinkHeader = 1;
+			}
+
+		}
+
+		retVal = newChunkId;
+
+	}
+
+	if (buffer)
+		yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+
+	return retVal;
+}
+
+/*------------------------ Short Operations Cache ----------------------------------------
+ *   In many situations where there is no high level buffering (eg WinCE) a lot of
+ *   reads might be short sequential reads, and a lot of writes may be short
+ *   sequential writes. eg. scanning/writing a jpeg file.
+ *   In these cases, a short read/write cache can provide a huge perfomance benefit
+ *   with dumb-as-a-rock code.
+ *   In Linux, the page cache provides read buffering aand the short op cache provides write
+ *   buffering.
+ *
+ *   There are a limited number (~10) of cache chunks per device so that we don't
+ *   need a very intelligent search.
+ */
+
+static int yaffs_ObjectHasCachedWriteData(yaffs_Object *obj)
+{
+	yaffs_Device *dev = obj->myDev;
+	int i;
+	yaffs_ChunkCache *cache;
+	int nCaches = obj->myDev->param.nShortOpCaches;
+
+	for (i = 0; i < nCaches; i++) {
+		cache = &dev->srCache[i];
+		if (cache->object == obj &&
+		    cache->dirty)
+			return 1;
+	}
+
+	return 0;
+}
+
+
+static void yaffs_FlushFilesChunkCache(yaffs_Object *obj)
+{
+	yaffs_Device *dev = obj->myDev;
+	int lowest = -99;	/* Stop compiler whining. */
+	int i;
+	yaffs_ChunkCache *cache;
+	int chunkWritten = 0;
+	int nCaches = obj->myDev->param.nShortOpCaches;
+
+	if (nCaches > 0) {
+		do {
+			cache = NULL;
+
+			/* Find the dirty cache for this object with the lowest chunk id. */
+			for (i = 0; i < nCaches; i++) {
+				if (dev->srCache[i].object == obj &&
+				    dev->srCache[i].dirty) {
+					if (!cache
+					    || dev->srCache[i].chunkId <
+					    lowest) {
+						cache = &dev->srCache[i];
+						lowest = cache->chunkId;
+					}
+				}
+			}
+
+			if (cache && !cache->locked) {
+				/* Write it out and free it up */
+
+				chunkWritten =
+				    yaffs_WriteChunkDataToObject(cache->object,
+								 cache->chunkId,
+								 cache->data,
+								 cache->nBytes,
+								 1);
+				cache->dirty = 0;
+				cache->object = NULL;
+			}
+
+		} while (cache && chunkWritten > 0);
+
+		if (cache) {
+			/* Hoosterman, disk full while writing cache out. */
+			T(YAFFS_TRACE_ERROR,
+			  (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
+
+		}
+	}
+
+}
+
+/*yaffs_FlushEntireDeviceCache(dev)
+ *
+ *
+ */
+
+void yaffs_FlushEntireDeviceCache(yaffs_Device *dev)
+{
+	yaffs_Object *obj;
+	int nCaches = dev->param.nShortOpCaches;
+	int i;
+
+	/* Find a dirty object in the cache and flush it...
+	 * until there are no further dirty objects.
+	 */
+	do {
+		obj = NULL;
+		for (i = 0; i < nCaches && !obj; i++) {
+			if (dev->srCache[i].object &&
+			    dev->srCache[i].dirty)
+				obj = dev->srCache[i].object;
+
+		}
+		if (obj)
+			yaffs_FlushFilesChunkCache(obj);
+
+	} while (obj);
+
+}
+
+
+/* Grab us a cache chunk for use.
+ * First look for an empty one.
+ * Then look for the least recently used non-dirty one.
+ * Then look for the least recently used dirty one...., flush and look again.
+ */
+static yaffs_ChunkCache *yaffs_GrabChunkCacheWorker(yaffs_Device *dev)
+{
+	int i;
+
+	if (dev->param.nShortOpCaches > 0) {
+		for (i = 0; i < dev->param.nShortOpCaches; i++) {
+			if (!dev->srCache[i].object)
+				return &dev->srCache[i];
+		}
+	}
+
+	return NULL;
+}
+
+static yaffs_ChunkCache *yaffs_GrabChunkCache(yaffs_Device *dev)
+{
+	yaffs_ChunkCache *cache;
+	yaffs_Object *theObj;
+	int usage;
+	int i;
+	int pushout;
+
+	if (dev->param.nShortOpCaches > 0) {
+		/* Try find a non-dirty one... */
+
+		cache = yaffs_GrabChunkCacheWorker(dev);
+
+		if (!cache) {
+			/* They were all dirty, find the last recently used object and flush
+			 * its cache, then  find again.
+			 * NB what's here is not very accurate, we actually flush the object
+			 * the last recently used page.
+			 */
+
+			/* With locking we can't assume we can use entry zero */
+
+			theObj = NULL;
+			usage = -1;
+			cache = NULL;
+			pushout = -1;
+
+			for (i = 0; i < dev->param.nShortOpCaches; i++) {
+				if (dev->srCache[i].object &&
+				    !dev->srCache[i].locked &&
+				    (dev->srCache[i].lastUse < usage || !cache)) {
+					usage = dev->srCache[i].lastUse;
+					theObj = dev->srCache[i].object;
+					cache = &dev->srCache[i];
+					pushout = i;
+				}
+			}
+
+			if (!cache || cache->dirty) {
+				/* Flush and try again */
+				yaffs_FlushFilesChunkCache(theObj);
+				cache = yaffs_GrabChunkCacheWorker(dev);
+			}
+
+		}
+		return cache;
+	} else
+		return NULL;
+
+}
+
+/* Find a cached chunk */
+static yaffs_ChunkCache *yaffs_FindChunkCache(const yaffs_Object *obj,
+					      int chunkId)
+{
+	yaffs_Device *dev = obj->myDev;
+	int i;
+	if (dev->param.nShortOpCaches > 0) {
+		for (i = 0; i < dev->param.nShortOpCaches; i++) {
+			if (dev->srCache[i].object == obj &&
+			    dev->srCache[i].chunkId == chunkId) {
+				dev->cacheHits++;
+
+				return &dev->srCache[i];
+			}
+		}
+	}
+	return NULL;
+}
+
+/* Mark the chunk for the least recently used algorithym */
+static void yaffs_UseChunkCache(yaffs_Device *dev, yaffs_ChunkCache *cache,
+				int isAWrite)
+{
+
+	if (dev->param.nShortOpCaches > 0) {
+		if (dev->srLastUse < 0 || dev->srLastUse > 100000000) {
+			/* Reset the cache usages */
+			int i;
+			for (i = 1; i < dev->param.nShortOpCaches; i++)
+				dev->srCache[i].lastUse = 0;
+
+			dev->srLastUse = 0;
+		}
+
+		dev->srLastUse++;
+
+		cache->lastUse = dev->srLastUse;
+
+		if (isAWrite)
+			cache->dirty = 1;
+	}
+}
+
+/* Invalidate a single cache page.
+ * Do this when a whole page gets written,
+ * ie the short cache for this page is no longer valid.
+ */
+static void yaffs_InvalidateChunkCache(yaffs_Object *object, int chunkId)
+{
+	if (object->myDev->param.nShortOpCaches > 0) {
+		yaffs_ChunkCache *cache = yaffs_FindChunkCache(object, chunkId);
+
+		if (cache)
+			cache->object = NULL;
+	}
+}
+
+/* Invalidate all the cache pages associated with this object
+ * Do this whenever ther file is deleted or resized.
+ */
+static void yaffs_InvalidateWholeChunkCache(yaffs_Object *in)
+{
+	int i;
+	yaffs_Device *dev = in->myDev;
+
+	if (dev->param.nShortOpCaches > 0) {
+		/* Invalidate it. */
+		for (i = 0; i < dev->param.nShortOpCaches; i++) {
+			if (dev->srCache[i].object == in)
+				dev->srCache[i].object = NULL;
+		}
+	}
+}
+
+/*--------------------- Checkpointing --------------------*/
+
+
+static int yaffs_WriteCheckpointValidityMarker(yaffs_Device *dev, int head)
+{
+	yaffs_CheckpointValidity cp;
+
+	memset(&cp, 0, sizeof(cp));
+
+	cp.structType = sizeof(cp);
+	cp.magic = YAFFS_MAGIC;
+	cp.version = YAFFS_CHECKPOINT_VERSION;
+	cp.head = (head) ? 1 : 0;
+
+	return (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp)) ?
+		1 : 0;
+}
+
+static int yaffs_ReadCheckpointValidityMarker(yaffs_Device *dev, int head)
+{
+	yaffs_CheckpointValidity cp;
+	int ok;
+
+	ok = (yaffs_CheckpointRead(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+	if (ok)
+		ok = (cp.structType == sizeof(cp)) &&
+		     (cp.magic == YAFFS_MAGIC) &&
+		     (cp.version == YAFFS_CHECKPOINT_VERSION) &&
+		     (cp.head == ((head) ? 1 : 0));
+	return ok ? 1 : 0;
+}
+
+static void yaffs_DeviceToCheckpointDevice(yaffs_CheckpointDevice *cp,
+					   yaffs_Device *dev)
+{
+	cp->nErasedBlocks = dev->nErasedBlocks;
+	cp->allocationBlock = dev->allocationBlock;
+	cp->allocationPage = dev->allocationPage;
+	cp->nFreeChunks = dev->nFreeChunks;
+
+	cp->nDeletedFiles = dev->nDeletedFiles;
+	cp->nUnlinkedFiles = dev->nUnlinkedFiles;
+	cp->nBackgroundDeletions = dev->nBackgroundDeletions;
+	cp->sequenceNumber = dev->sequenceNumber;
+
+}
+
+static void yaffs_CheckpointDeviceToDevice(yaffs_Device *dev,
+					   yaffs_CheckpointDevice *cp)
+{
+	dev->nErasedBlocks = cp->nErasedBlocks;
+	dev->allocationBlock = cp->allocationBlock;
+	dev->allocationPage = cp->allocationPage;
+	dev->nFreeChunks = cp->nFreeChunks;
+
+	dev->nDeletedFiles = cp->nDeletedFiles;
+	dev->nUnlinkedFiles = cp->nUnlinkedFiles;
+	dev->nBackgroundDeletions = cp->nBackgroundDeletions;
+	dev->sequenceNumber = cp->sequenceNumber;
+}
+
+
+static int yaffs_WriteCheckpointDevice(yaffs_Device *dev)
+{
+	yaffs_CheckpointDevice cp;
+	__u32 nBytes;
+	__u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
+
+	int ok;
+
+	/* Write device runtime values*/
+	yaffs_DeviceToCheckpointDevice(&cp, dev);
+	cp.structType = sizeof(cp);
+
+	ok = (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+	/* Write block info */
+	if (ok) {
+		nBytes = nBlocks * sizeof(yaffs_BlockInfo);
+		ok = (yaffs_CheckpointWrite(dev, dev->blockInfo, nBytes) == nBytes);
+	}
+
+	/* Write chunk bits */
+	if (ok) {
+		nBytes = nBlocks * dev->chunkBitmapStride;
+		ok = (yaffs_CheckpointWrite(dev, dev->chunkBits, nBytes) == nBytes);
+	}
+	return	 ok ? 1 : 0;
+
+}
+
+static int yaffs_ReadCheckpointDevice(yaffs_Device *dev)
+{
+	yaffs_CheckpointDevice cp;
+	__u32 nBytes;
+	__u32 nBlocks = (dev->internalEndBlock - dev->internalStartBlock + 1);
+
+	int ok;
+
+	ok = (yaffs_CheckpointRead(dev, &cp, sizeof(cp)) == sizeof(cp));
+	if (!ok)
+		return 0;
+
+	if (cp.structType != sizeof(cp))
+		return 0;
+
+
+	yaffs_CheckpointDeviceToDevice(dev, &cp);
+
+	nBytes = nBlocks * sizeof(yaffs_BlockInfo);
+
+	ok = (yaffs_CheckpointRead(dev, dev->blockInfo, nBytes) == nBytes);
+
+	if (!ok)
+		return 0;
+	nBytes = nBlocks * dev->chunkBitmapStride;
+
+	ok = (yaffs_CheckpointRead(dev, dev->chunkBits, nBytes) == nBytes);
+
+	return ok ? 1 : 0;
+}
+
+static void yaffs_ObjectToCheckpointObject(yaffs_CheckpointObject *cp,
+					   yaffs_Object *obj)
+{
+
+	cp->objectId = obj->objectId;
+	cp->parentId = (obj->parent) ? obj->parent->objectId : 0;
+	cp->hdrChunk = obj->hdrChunk;
+	cp->variantType = obj->variantType;
+	cp->deleted = obj->deleted;
+	cp->softDeleted = obj->softDeleted;
+	cp->unlinked = obj->unlinked;
+	cp->fake = obj->fake;
+	cp->renameAllowed = obj->renameAllowed;
+	cp->unlinkAllowed = obj->unlinkAllowed;
+	cp->serial = obj->serial;
+	cp->nDataChunks = obj->nDataChunks;
+
+	if (obj->variantType == YAFFS_OBJECT_TYPE_FILE)
+		cp->fileSizeOrEquivalentObjectId = obj->variant.fileVariant.fileSize;
+	else if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
+		cp->fileSizeOrEquivalentObjectId = obj->variant.hardLinkVariant.equivalentObjectId;
+}
+
+static int yaffs_CheckpointObjectToObject(yaffs_Object *obj, yaffs_CheckpointObject *cp)
+{
+
+	yaffs_Object *parent;
+
+	if (obj->variantType != cp->variantType) {
+		T(YAFFS_TRACE_ERROR, (TSTR("Checkpoint read object %d type %d "
+			TCONT("chunk %d does not match existing object type %d")
+			TENDSTR), cp->objectId, cp->variantType, cp->hdrChunk,
+			obj->variantType));
+		return 0;
+	}
+
+	obj->objectId = cp->objectId;
+
+	if (cp->parentId)
+		parent = yaffs_FindOrCreateObjectByNumber(
+					obj->myDev,
+					cp->parentId,
+					YAFFS_OBJECT_TYPE_DIRECTORY);
+	else
+		parent = NULL;
+
+	if (parent) {
+		if (parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+			T(YAFFS_TRACE_ALWAYS, (TSTR("Checkpoint read object %d parent %d type %d"
+				TCONT(" chunk %d Parent type, %d, not directory")
+				TENDSTR),
+				cp->objectId, cp->parentId, cp->variantType,
+				cp->hdrChunk, parent->variantType));
+			return 0;
+		}
+		yaffs_AddObjectToDirectory(parent, obj);
+	}
+
+	obj->hdrChunk = cp->hdrChunk;
+	obj->variantType = cp->variantType;
+	obj->deleted = cp->deleted;
+	obj->softDeleted = cp->softDeleted;
+	obj->unlinked = cp->unlinked;
+	obj->fake = cp->fake;
+	obj->renameAllowed = cp->renameAllowed;
+	obj->unlinkAllowed = cp->unlinkAllowed;
+	obj->serial = cp->serial;
+	obj->nDataChunks = cp->nDataChunks;
+
+	if (obj->variantType == YAFFS_OBJECT_TYPE_FILE)
+		obj->variant.fileVariant.fileSize = cp->fileSizeOrEquivalentObjectId;
+	else if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK)
+		obj->variant.hardLinkVariant.equivalentObjectId = cp->fileSizeOrEquivalentObjectId;
+
+	if (obj->hdrChunk > 0)
+		obj->lazyLoaded = 1;
+	return 1;
+}
+
+
+
+static int yaffs_CheckpointTnodeWorker(yaffs_Object *in, yaffs_Tnode *tn,
+					__u32 level, int chunkOffset)
+{
+	int i;
+	yaffs_Device *dev = in->myDev;
+	int ok = 1;
+	int tnodeSize = yaffs_CalcTnodeSize(dev);
+
+	if (tn) {
+		if (level > 0) {
+
+			for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) {
+				if (tn->internal[i]) {
+					ok = yaffs_CheckpointTnodeWorker(in,
+							tn->internal[i],
+							level - 1,
+							(chunkOffset<<YAFFS_TNODES_INTERNAL_BITS) + i);
+				}
+			}
+		} else if (level == 0) {
+			__u32 baseOffset = chunkOffset <<  YAFFS_TNODES_LEVEL0_BITS;
+			ok = (yaffs_CheckpointWrite(dev, &baseOffset, sizeof(baseOffset)) == sizeof(baseOffset));
+			if (ok)
+				ok = (yaffs_CheckpointWrite(dev, tn, tnodeSize) == tnodeSize);
+		}
+	}
+
+	return ok;
+
+}
+
+static int yaffs_WriteCheckpointTnodes(yaffs_Object *obj)
+{
+	__u32 endMarker = ~0;
+	int ok = 1;
+
+	if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
+		ok = yaffs_CheckpointTnodeWorker(obj,
+					    obj->variant.fileVariant.top,
+					    obj->variant.fileVariant.topLevel,
+					    0);
+		if (ok)
+			ok = (yaffs_CheckpointWrite(obj->myDev, &endMarker, sizeof(endMarker)) ==
+				sizeof(endMarker));
+	}
+
+	return ok ? 1 : 0;
+}
+
+static int yaffs_ReadCheckpointTnodes(yaffs_Object *obj)
+{
+	__u32 baseChunk;
+	int ok = 1;
+	yaffs_Device *dev = obj->myDev;
+	yaffs_FileStructure *fileStructPtr = &obj->variant.fileVariant;
+	yaffs_Tnode *tn;
+	int nread = 0;
+	int tnodeSize = yaffs_CalcTnodeSize(dev);
+
+	ok = (yaffs_CheckpointRead(dev, &baseChunk, sizeof(baseChunk)) == sizeof(baseChunk));
+
+	while (ok && (~baseChunk)) {
+		nread++;
+		/* Read level 0 tnode */
+
+
+		tn = yaffs_GetTnodeRaw(dev);
+		if (tn)
+			ok = (yaffs_CheckpointRead(dev, tn, tnodeSize) == tnodeSize);
+		else
+			ok = 0;
+
+		if (tn && ok)
+			ok = yaffs_AddOrFindLevel0Tnode(dev,
+							fileStructPtr,
+							baseChunk,
+							tn) ? 1 : 0;
+
+		if (ok)
+			ok = (yaffs_CheckpointRead(dev, &baseChunk, sizeof(baseChunk)) == sizeof(baseChunk));
+
+	}
+
+	T(YAFFS_TRACE_CHECKPOINT, (
+		TSTR("Checkpoint read tnodes %d records, last %d. ok %d" TENDSTR),
+		nread, baseChunk, ok));
+
+	return ok ? 1 : 0;
+}
+
+
+static int yaffs_WriteCheckpointObjects(yaffs_Device *dev)
+{
+	yaffs_Object *obj;
+	yaffs_CheckpointObject cp;
+	int i;
+	int ok = 1;
+	struct ylist_head *lh;
+
+
+	/* Iterate through the objects in each hash entry,
+	 * dumping them to the checkpointing stream.
+	 */
+
+	for (i = 0; ok &&  i <  YAFFS_NOBJECT_BUCKETS; i++) {
+		ylist_for_each(lh, &dev->objectBucket[i].list) {
+			if (lh) {
+				obj = ylist_entry(lh, yaffs_Object, hashLink);
+				if (!obj->deferedFree) {
+					yaffs_ObjectToCheckpointObject(&cp, obj);
+					cp.structType = sizeof(cp);
+
+					T(YAFFS_TRACE_CHECKPOINT, (
+						TSTR("Checkpoint write object %d parent %d type %d chunk %d obj addr %p" TENDSTR),
+						cp.objectId, cp.parentId, cp.variantType, cp.hdrChunk, obj));
+
+					ok = (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+					if (ok && obj->variantType == YAFFS_OBJECT_TYPE_FILE)
+						ok = yaffs_WriteCheckpointTnodes(obj);
+				}
+			}
+		}
+	}
+
+	/* Dump end of list */
+	memset(&cp, 0xFF, sizeof(yaffs_CheckpointObject));
+	cp.structType = sizeof(cp);
+
+	if (ok)
+		ok = (yaffs_CheckpointWrite(dev, &cp, sizeof(cp)) == sizeof(cp));
+
+	return ok ? 1 : 0;
+}
+
+static int yaffs_ReadCheckpointObjects(yaffs_Device *dev)
+{
+	yaffs_Object *obj;
+	yaffs_CheckpointObject cp;
+	int ok = 1;
+	int done = 0;
+	yaffs_Object *hardList = NULL;
+
+	while (ok && !done) {
+		ok = (yaffs_CheckpointRead(dev, &cp, sizeof(cp)) == sizeof(cp));
+		if (cp.structType != sizeof(cp)) {
+			T(YAFFS_TRACE_CHECKPOINT, (TSTR("struct size %d instead of %d ok %d"TENDSTR),
+				cp.structType, (int)sizeof(cp), ok));
+			ok = 0;
+		}
+
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("Checkpoint read object %d parent %d type %d chunk %d " TENDSTR),
+			cp.objectId, cp.parentId, cp.variantType, cp.hdrChunk));
+
+		if (ok && cp.objectId == ~0)
+			done = 1;
+		else if (ok) {
+			obj = yaffs_FindOrCreateObjectByNumber(dev, cp.objectId, cp.variantType);
+			if (obj) {
+				ok = yaffs_CheckpointObjectToObject(obj, &cp);
+				if (!ok)
+					break;
+				if (obj->variantType == YAFFS_OBJECT_TYPE_FILE) {
+					ok = yaffs_ReadCheckpointTnodes(obj);
+				} else if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
+					obj->hardLinks.next =
+						(struct ylist_head *) hardList;
+					hardList = obj;
+				}
+			} else
+				ok = 0;
+		}
+	}
+
+	if (ok)
+		yaffs_HardlinkFixup(dev, hardList);
+
+	return ok ? 1 : 0;
+}
+
+static int yaffs_WriteCheckpointSum(yaffs_Device *dev)
+{
+	__u32 checkpointSum;
+	int ok;
+
+	yaffs_GetCheckpointSum(dev, &checkpointSum);
+
+	ok = (yaffs_CheckpointWrite(dev, &checkpointSum, sizeof(checkpointSum)) == sizeof(checkpointSum));
+
+	if (!ok)
+		return 0;
+
+	return 1;
+}
+
+static int yaffs_ReadCheckpointSum(yaffs_Device *dev)
+{
+	__u32 checkpointSum0;
+	__u32 checkpointSum1;
+	int ok;
+
+	yaffs_GetCheckpointSum(dev, &checkpointSum0);
+
+	ok = (yaffs_CheckpointRead(dev, &checkpointSum1, sizeof(checkpointSum1)) == sizeof(checkpointSum1));
+
+	if (!ok)
+		return 0;
+
+	if (checkpointSum0 != checkpointSum1)
+		return 0;
+
+	return 1;
+}
+
+
+static int yaffs_WriteCheckpointData(yaffs_Device *dev)
+{
+	int ok = 1;
+
+	if (!yaffs_CheckpointRequired(dev)) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("skipping checkpoint write" TENDSTR)));
+		ok = 0;
+	}
+
+	if (ok)
+		ok = yaffs_CheckpointOpen(dev, 1);
+
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint validity" TENDSTR)));
+		ok = yaffs_WriteCheckpointValidityMarker(dev, 1);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint device" TENDSTR)));
+		ok = yaffs_WriteCheckpointDevice(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint objects" TENDSTR)));
+		ok = yaffs_WriteCheckpointObjects(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("write checkpoint validity" TENDSTR)));
+		ok = yaffs_WriteCheckpointValidityMarker(dev, 0);
+	}
+
+	if (ok)
+		ok = yaffs_WriteCheckpointSum(dev);
+
+	if (!yaffs_CheckpointClose(dev))
+		ok = 0;
+
+	if (ok)
+		dev->isCheckpointed = 1;
+	else
+		dev->isCheckpointed = 0;
+
+	return dev->isCheckpointed;
+}
+
+static int yaffs_ReadCheckpointData(yaffs_Device *dev)
+{
+	int ok = 1;
+
+	if (dev->param.skipCheckpointRead || !dev->param.isYaffs2) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("skipping checkpoint read" TENDSTR)));
+		ok = 0;
+	}
+
+	if (ok)
+		ok = yaffs_CheckpointOpen(dev, 0); /* open for read */
+
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint validity" TENDSTR)));
+		ok = yaffs_ReadCheckpointValidityMarker(dev, 1);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint device" TENDSTR)));
+		ok = yaffs_ReadCheckpointDevice(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint objects" TENDSTR)));
+		ok = yaffs_ReadCheckpointObjects(dev);
+	}
+	if (ok) {
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint validity" TENDSTR)));
+		ok = yaffs_ReadCheckpointValidityMarker(dev, 0);
+	}
+
+	if (ok) {
+		ok = yaffs_ReadCheckpointSum(dev);
+		T(YAFFS_TRACE_CHECKPOINT, (TSTR("read checkpoint checksum %d" TENDSTR), ok));
+	}
+
+	if (!yaffs_CheckpointClose(dev))
+		ok = 0;
+
+	if (ok)
+		dev->isCheckpointed = 1;
+	else
+		dev->isCheckpointed = 0;
+
+	return ok ? 1 : 0;
+
+}
+
+static void yaffs_InvalidateCheckpoint(yaffs_Device *dev)
+{
+	if (dev->isCheckpointed ||
+			dev->blocksInCheckpoint > 0) {
+		dev->isCheckpointed = 0;
+		yaffs_CheckpointInvalidateStream(dev);
+	}
+	if (dev->param.markSuperBlockDirty)
+		dev->param.markSuperBlockDirty(dev);
+}
+
+
+int yaffs_CheckpointSave(yaffs_Device *dev)
+{
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("save entry: isCheckpointed %d"TENDSTR), dev->isCheckpointed));
+
+	yaffs_VerifyObjects(dev);
+	yaffs_VerifyBlocks(dev);
+	yaffs_VerifyFreeChunks(dev);
+
+	if (!dev->isCheckpointed) {
+		yaffs_InvalidateCheckpoint(dev);
+		yaffs_WriteCheckpointData(dev);
+	}
+
+	T(YAFFS_TRACE_ALWAYS, (TSTR("save exit: isCheckpointed %d"TENDSTR), dev->isCheckpointed));
+
+	return dev->isCheckpointed;
+}
+
+int yaffs_CheckpointRestore(yaffs_Device *dev)
+{
+	int retval;
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("restore entry: isCheckpointed %d"TENDSTR), dev->isCheckpointed));
+
+	retval = yaffs_ReadCheckpointData(dev);
+
+	if (dev->isCheckpointed) {
+		yaffs_VerifyObjects(dev);
+		yaffs_VerifyBlocks(dev);
+		yaffs_VerifyFreeChunks(dev);
+	}
+
+	T(YAFFS_TRACE_CHECKPOINT, (TSTR("restore exit: isCheckpointed %d"TENDSTR), dev->isCheckpointed));
+
+	return retval;
+}
+
+/*--------------------- File read/write ------------------------
+ * Read and write have very similar structures.
+ * In general the read/write has three parts to it
+ * An incomplete chunk to start with (if the read/write is not chunk-aligned)
+ * Some complete chunks
+ * An incomplete chunk to end off with
+ *
+ * Curve-balls: the first chunk might also be the last chunk.
+ */
+
+int yaffs_ReadDataFromFile(yaffs_Object *in, __u8 *buffer, loff_t offset,
+			int nBytes)
+{
+
+	int chunk;
+	__u32 start;
+	int nToCopy;
+	int n = nBytes;
+	int nDone = 0;
+	yaffs_ChunkCache *cache;
+
+	yaffs_Device *dev;
+
+	dev = in->myDev;
+
+	while (n > 0) {
+		/* chunk = offset / dev->nDataBytesPerChunk + 1; */
+		/* start = offset % dev->nDataBytesPerChunk; */
+		yaffs_AddrToChunk(dev, offset, &chunk, &start);
+		chunk++;
+
+		/* OK now check for the curveball where the start and end are in
+		 * the same chunk.
+		 */
+		if ((start + n) < dev->nDataBytesPerChunk)
+			nToCopy = n;
+		else
+			nToCopy = dev->nDataBytesPerChunk - start;
+
+		cache = yaffs_FindChunkCache(in, chunk);
+
+		/* If the chunk is already in the cache or it is less than a whole chunk
+		 * or we're using inband tags then use the cache (if there is caching)
+		 * else bypass the cache.
+		 */
+		if (cache || nToCopy != dev->nDataBytesPerChunk || dev->param.inbandTags) {
+			if (dev->param.nShortOpCaches > 0) {
+
+				/* If we can't find the data in the cache, then load it up. */
+
+				if (!cache) {
+					cache = yaffs_GrabChunkCache(in->myDev);
+					cache->object = in;
+					cache->chunkId = chunk;
+					cache->dirty = 0;
+					cache->locked = 0;
+					yaffs_ReadChunkDataFromObject(in, chunk,
+								      cache->
+								      data);
+					cache->nBytes = 0;
+				}
+
+				yaffs_UseChunkCache(dev, cache, 0);
+
+				cache->locked = 1;
+
+
+				memcpy(buffer, &cache->data[start], nToCopy);
+
+				cache->locked = 0;
+			} else {
+				/* Read into the local buffer then copy..*/
+
+				__u8 *localBuffer =
+				    yaffs_GetTempBuffer(dev, __LINE__);
+				yaffs_ReadChunkDataFromObject(in, chunk,
+							      localBuffer);
+
+				memcpy(buffer, &localBuffer[start], nToCopy);
+
+
+				yaffs_ReleaseTempBuffer(dev, localBuffer,
+							__LINE__);
+			}
+
+		} else {
+
+			/* A full chunk. Read directly into the supplied buffer. */
+			yaffs_ReadChunkDataFromObject(in, chunk, buffer);
+
+		}
+
+		n -= nToCopy;
+		offset += nToCopy;
+		buffer += nToCopy;
+		nDone += nToCopy;
+
+	}
+
+	return nDone;
+}
+
+int yaffs_DoWriteDataToFile(yaffs_Object *in, const __u8 *buffer, loff_t offset,
+			int nBytes, int writeThrough)
+{
+
+	int chunk;
+	__u32 start;
+	int nToCopy;
+	int n = nBytes;
+	int nDone = 0;
+	int nToWriteBack;
+	int startOfWrite = offset;
+	int chunkWritten = 0;
+	__u32 nBytesRead;
+	__u32 chunkStart;
+
+	yaffs_Device *dev;
+
+	dev = in->myDev;
+
+	while (n > 0 && chunkWritten >= 0) {
+		yaffs_AddrToChunk(dev, offset, &chunk, &start);
+
+		if (chunk * dev->nDataBytesPerChunk + start != offset ||
+				start >= dev->nDataBytesPerChunk) {
+			T(YAFFS_TRACE_ERROR, (
+			   TSTR("AddrToChunk of offset %d gives chunk %d start %d"
+			   TENDSTR),
+			   (int)offset, chunk, start));
+		}
+		chunk++; /* File pos to chunk in file offset */
+
+		/* OK now check for the curveball where the start and end are in
+		 * the same chunk.
+		 */
+
+		if ((start + n) < dev->nDataBytesPerChunk) {
+			nToCopy = n;
+
+			/* Now folks, to calculate how many bytes to write back....
+			 * If we're overwriting and not writing to then end of file then
+			 * we need to write back as much as was there before.
+			 */
+
+			chunkStart = ((chunk - 1) * dev->nDataBytesPerChunk);
+
+			if (chunkStart > in->variant.fileVariant.fileSize)
+				nBytesRead = 0; /* Past end of file */
+			else
+				nBytesRead = in->variant.fileVariant.fileSize - chunkStart;
+
+			if (nBytesRead > dev->nDataBytesPerChunk)
+				nBytesRead = dev->nDataBytesPerChunk;
+
+			nToWriteBack =
+			    (nBytesRead >
+			     (start + n)) ? nBytesRead : (start + n);
+
+			if (nToWriteBack < 0 || nToWriteBack > dev->nDataBytesPerChunk)
+				YBUG();
+
+		} else {
+			nToCopy = dev->nDataBytesPerChunk - start;
+			nToWriteBack = dev->nDataBytesPerChunk;
+		}
+
+		if (nToCopy != dev->nDataBytesPerChunk || dev->param.inbandTags) {
+			/* An incomplete start or end chunk (or maybe both start and end chunk),
+			 * or we're using inband tags, so we want to use the cache buffers.
+			 */
+			if (dev->param.nShortOpCaches > 0) {
+				yaffs_ChunkCache *cache;
+				/* If we can't find the data in the cache, then load the cache */
+				cache = yaffs_FindChunkCache(in, chunk);
+
+				if (!cache
+				    && yaffs_CheckSpaceForAllocation(dev, 1)) {
+					cache = yaffs_GrabChunkCache(dev);
+					cache->object = in;
+					cache->chunkId = chunk;
+					cache->dirty = 0;
+					cache->locked = 0;
+					yaffs_ReadChunkDataFromObject(in, chunk,
+								      cache->data);
+				} else if (cache &&
+					!cache->dirty &&
+					!yaffs_CheckSpaceForAllocation(dev, 1)) {
+					/* Drop the cache if it was a read cache item and
+					 * no space check has been made for it.
+					 */
+					 cache = NULL;
+				}
+
+				if (cache) {
+					yaffs_UseChunkCache(dev, cache, 1);
+					cache->locked = 1;
+
+
+					memcpy(&cache->data[start], buffer,
+					       nToCopy);
+
+
+					cache->locked = 0;
+					cache->nBytes = nToWriteBack;
+
+					if (writeThrough) {
+						chunkWritten =
+						    yaffs_WriteChunkDataToObject
+						    (cache->object,
+						     cache->chunkId,
+						     cache->data, cache->nBytes,
+						     1);
+						cache->dirty = 0;
+					}
+
+				} else {
+					chunkWritten = -1;	/* fail the write */
+				}
+			} else {
+				/* An incomplete start or end chunk (or maybe both start and end chunk)
+				 * Read into the local buffer then copy, then copy over and write back.
+				 */
+
+				__u8 *localBuffer =
+				    yaffs_GetTempBuffer(dev, __LINE__);
+
+				yaffs_ReadChunkDataFromObject(in, chunk,
+							      localBuffer);
+
+
+
+				memcpy(&localBuffer[start], buffer, nToCopy);
+
+				chunkWritten =
+				    yaffs_WriteChunkDataToObject(in, chunk,
+								 localBuffer,
+								 nToWriteBack,
+								 0);
+
+				yaffs_ReleaseTempBuffer(dev, localBuffer,
+							__LINE__);
+
+			}
+
+		} else {
+			/* A full chunk. Write directly from the supplied buffer. */
+
+
+
+			chunkWritten =
+			    yaffs_WriteChunkDataToObject(in, chunk, buffer,
+							 dev->nDataBytesPerChunk,
+							 0);
+
+			/* Since we've overwritten the cached data, we better invalidate it. */
+			yaffs_InvalidateChunkCache(in, chunk);
+		}
+
+		if (chunkWritten >= 0) {
+			n -= nToCopy;
+			offset += nToCopy;
+			buffer += nToCopy;
+			nDone += nToCopy;
+		}
+
+	}
+
+	/* Update file object */
+
+	if ((startOfWrite + nDone) > in->variant.fileVariant.fileSize)
+		in->variant.fileVariant.fileSize = (startOfWrite + nDone);
+
+	in->dirty = 1;
+
+	return nDone;
+}
+
+int yaffs_WriteDataToFile(yaffs_Object *in, const __u8 *buffer, loff_t offset,
+			int nBytes, int writeThrough)
+{
+	yaffs_HandleHole(in,offset);
+	return yaffs_DoWriteDataToFile(in,buffer,offset,nBytes,writeThrough);
+}
+
+
+
+/* ---------------------- File resizing stuff ------------------ */
+
+static void yaffs_PruneResizedChunks(yaffs_Object *in, int newSize)
+{
+
+	yaffs_Device *dev = in->myDev;
+	int oldFileSize = in->variant.fileVariant.fileSize;
+
+	int lastDel = 1 + (oldFileSize - 1) / dev->nDataBytesPerChunk;
+
+	int startDel = 1 + (newSize + dev->nDataBytesPerChunk - 1) /
+	    dev->nDataBytesPerChunk;
+	int i;
+	int chunkId;
+
+	/* Delete backwards so that we don't end up with holes if
+	 * power is lost part-way through the operation.
+	 */
+	for (i = lastDel; i >= startDel; i--) {
+		/* NB this could be optimised somewhat,
+		 * eg. could retrieve the tags and write them without
+		 * using yaffs_DeleteChunk
+		 */
+
+		chunkId = yaffs_FindAndDeleteChunkInFile(in, i, NULL);
+		if (chunkId > 0) {
+			if (chunkId <
+			    (dev->internalStartBlock * dev->param.nChunksPerBlock)
+			    || chunkId >=
+			    ((dev->internalEndBlock +
+			      1) * dev->param.nChunksPerBlock)) {
+				T(YAFFS_TRACE_ALWAYS,
+				  (TSTR("Found daft chunkId %d for %d" TENDSTR),
+				   chunkId, i));
+			} else {
+				in->nDataChunks--;
+				yaffs_DeleteChunk(dev, chunkId, 1, __LINE__);
+			}
+		}
+	}
+
+}
+
+
+static void yaffs_ResizeDown( yaffs_Object *obj, loff_t newSize)
+{
+	int newFullChunks;
+	__u32 newSizeOfPartialChunk;
+	yaffs_Device *dev = obj->myDev;
+
+	yaffs_AddrToChunk(dev, newSize, &newFullChunks, &newSizeOfPartialChunk);
+
+	yaffs_PruneResizedChunks(obj, newSize);
+
+	if (newSizeOfPartialChunk != 0) {
+		int lastChunk = 1 + newFullChunks;
+		__u8 *localBuffer = yaffs_GetTempBuffer(dev, __LINE__);
+
+		/* Got to read and rewrite the last chunk with its new size and zero pad */
+		yaffs_ReadChunkDataFromObject(obj, lastChunk, localBuffer);
+		memset(localBuffer + newSizeOfPartialChunk, 0,
+			dev->nDataBytesPerChunk - newSizeOfPartialChunk);
+
+		yaffs_WriteChunkDataToObject(obj, lastChunk, localBuffer,
+					     newSizeOfPartialChunk, 1);
+
+		yaffs_ReleaseTempBuffer(dev, localBuffer, __LINE__);
+	}
+
+	obj->variant.fileVariant.fileSize = newSize;
+
+	yaffs_PruneFileStructure(dev, &obj->variant.fileVariant);
+}
+
+
+static int yaffs_HandleHole(yaffs_Object *obj, loff_t newSize)
+{
+	/* if newsSize > oldFileSize.
+	 * We're going to be writing a hole.
+	 * If the hole is small then write zeros otherwise write a start of hole marker.
+	 */
+		
+
+	loff_t oldFileSize;
+	int increase;
+	int smallHole   ;
+	int result = YAFFS_OK;
+	yaffs_Device *dev = NULL;
+
+	__u8 *localBuffer = NULL;
+	
+	int smallIncreaseOk = 0;
+	
+	if(!obj)
+		return YAFFS_FAIL;
+
+	if(obj->variantType != YAFFS_OBJECT_TYPE_FILE)
+		return YAFFS_FAIL;
+	
+	dev = obj->myDev;
+	
+	/* Bail out if not yaffs2 mode */
+	if(!dev->param.isYaffs2)
+		return YAFFS_OK;
+
+	oldFileSize = obj->variant.fileVariant.fileSize;
+
+	if (newSize <= oldFileSize)
+		return YAFFS_OK;
+
+	increase = newSize - oldFileSize;
+
+	if(increase < YAFFS_SMALL_HOLE_THRESHOLD * dev->nDataBytesPerChunk &&
+		yaffs_CheckSpaceForAllocation(dev, YAFFS_SMALL_HOLE_THRESHOLD + 1))
+		smallHole = 1;
+	else
+		smallHole = 0;
+
+	if(smallHole)
+		localBuffer= yaffs_GetTempBuffer(dev, __LINE__);
+	
+	if(localBuffer){
+		/* fill hole with zero bytes */
+		int pos = oldFileSize;
+		int thisWrite;
+		int written;
+		memset(localBuffer,0,dev->nDataBytesPerChunk);
+		smallIncreaseOk = 1;
+
+		while(increase > 0 && smallIncreaseOk){
+			thisWrite = increase;
+			if(thisWrite > dev->nDataBytesPerChunk)
+				thisWrite = dev->nDataBytesPerChunk;
+			written = yaffs_DoWriteDataToFile(obj,localBuffer,pos,thisWrite,0);
+			if(written == thisWrite){
+				pos += thisWrite;
+				increase -= thisWrite;
+			} else
+				smallIncreaseOk = 0;
+		}
+
+		yaffs_ReleaseTempBuffer(dev,localBuffer,__LINE__);
+
+		/* If we were out of space then reverse any chunks we've added */		
+		if(!smallIncreaseOk)
+			yaffs_ResizeDown(obj, oldFileSize);
+	}
+	
+	if (!smallIncreaseOk &&
+		obj->parent &&
+		obj->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
+		obj->parent->objectId != YAFFS_OBJECTID_DELETED){
+		/* Write a hole start header with the old file size */
+		yaffs_UpdateObjectHeader(obj, NULL, 0,1,0);
+	}
+
+	return result;
+
+}
+
+int yaffs_ResizeFile(yaffs_Object *in, loff_t newSize)
+{
+	yaffs_Device *dev = in->myDev;
+	int oldFileSize = in->variant.fileVariant.fileSize;
+
+	yaffs_FlushFilesChunkCache(in);
+	yaffs_InvalidateWholeChunkCache(in);
+
+	yaffs_CheckGarbageCollection(dev,0);
+
+	if (in->variantType != YAFFS_OBJECT_TYPE_FILE)
+		return YAFFS_FAIL;
+
+	if (newSize == oldFileSize)
+		return YAFFS_OK;
+		
+	if(newSize > oldFileSize){
+		yaffs_HandleHole(in,newSize);
+		in->variant.fileVariant.fileSize = newSize;
+	} else {
+		/* newSize < oldFileSize */ 
+		yaffs_ResizeDown(in, newSize);
+	} 
+
+	/* Write a new object header to reflect the resize.
+	 * show we've shrunk the file, if need be
+	 * Do this only if the file is not in the deleted directories
+	 * and is not shadowed.
+	 */
+	if (in->parent &&
+	    !in->isShadowed &&
+	    in->parent->objectId != YAFFS_OBJECTID_UNLINKED &&
+	    in->parent->objectId != YAFFS_OBJECTID_DELETED)
+		yaffs_UpdateObjectHeader(in, NULL, 0,0,0);
+
+
+	return YAFFS_OK;
+}
+
+loff_t yaffs_GetFileSize(yaffs_Object *obj)
+{
+	YCHAR *alias = NULL;
+	obj = yaffs_GetEquivalentObject(obj);
+
+	switch (obj->variantType) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		return obj->variant.fileVariant.fileSize;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		alias = obj->variant.symLinkVariant.alias;
+		if(!alias)
+			return 0;
+		return yaffs_strnlen(alias,YAFFS_MAX_ALIAS_LENGTH);
+	default:
+		return 0;
+	}
+}
+
+
+
+int yaffs_FlushFile(yaffs_Object *in, int updateTime, int dataSync)
+{
+	int retVal;
+	if (in->dirty) {
+		yaffs_FlushFilesChunkCache(in);
+		if(dataSync) /* Only sync data */
+			retVal=YAFFS_OK;
+		else {
+			if (updateTime) {
+#ifdef CONFIG_YAFFS_WINCE
+				yfsd_WinFileTimeNow(in->win_mtime);
+#else
+
+				in->yst_mtime = Y_CURRENT_TIME;
+
+#endif
+			}
+
+			retVal = (yaffs_UpdateObjectHeader(in, NULL, 0, 0, 0) >=
+				0) ? YAFFS_OK : YAFFS_FAIL;
+		}
+	} else {
+		retVal = YAFFS_OK;
+	}
+
+	return retVal;
+
+}
+
+static int yaffs_DoGenericObjectDeletion(yaffs_Object *in)
+{
+
+	/* First off, invalidate the file's data in the cache, without flushing. */
+	yaffs_InvalidateWholeChunkCache(in);
+
+	if (in->myDev->param.isYaffs2 && (in->parent != in->myDev->deletedDir)) {
+		/* Move to the unlinked directory so we have a record that it was deleted. */
+		yaffs_ChangeObjectName(in, in->myDev->deletedDir, _Y("deleted"), 0, 0);
+
+	}
+
+	yaffs_RemoveObjectFromDirectory(in);
+	yaffs_DeleteChunk(in->myDev, in->hdrChunk, 1, __LINE__);
+	in->hdrChunk = 0;
+
+	yaffs_FreeObject(in);
+	return YAFFS_OK;
+
+}
+
+/* yaffs_DeleteFile deletes the whole file data
+ * and the inode associated with the file.
+ * It does not delete the links associated with the file.
+ */
+static int yaffs_UnlinkFileIfNeeded(yaffs_Object *in)
+{
+
+	int retVal;
+	int immediateDeletion = 0;
+	yaffs_Device *dev = in->myDev;
+
+	if (!in->myInode)
+		immediateDeletion = 1;
+
+	if (immediateDeletion) {
+		retVal =
+		    yaffs_ChangeObjectName(in, in->myDev->deletedDir,
+					   _Y("deleted"), 0, 0);
+		T(YAFFS_TRACE_TRACING,
+		  (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
+		   in->objectId));
+		in->deleted = 1;
+		in->myDev->nDeletedFiles++;
+		if (dev->param.disableSoftDelete || dev->param.isYaffs2)
+			yaffs_ResizeFile(in, 0);
+		yaffs_SoftDeleteFile(in);
+	} else {
+		retVal =
+		    yaffs_ChangeObjectName(in, in->myDev->unlinkedDir,
+					   _Y("unlinked"), 0, 0);
+	}
+
+
+	return retVal;
+}
+
+int yaffs_DeleteFile(yaffs_Object *in)
+{
+	int retVal = YAFFS_OK;
+	int deleted; /* Need to cache value on stack if in is freed */
+	yaffs_Device *dev = in->myDev;
+
+	if (dev->param.disableSoftDelete || dev->param.isYaffs2)
+		yaffs_ResizeFile(in, 0);
+
+	if (in->nDataChunks > 0) {
+		/* Use soft deletion if there is data in the file.
+		 * That won't be the case if it has been resized to zero.
+		 */
+		if (!in->unlinked)
+			retVal = yaffs_UnlinkFileIfNeeded(in);
+
+		deleted = in->deleted;
+
+		if (retVal == YAFFS_OK && in->unlinked && !in->deleted) {
+			in->deleted = 1;
+			deleted = 1;
+			in->myDev->nDeletedFiles++;
+			yaffs_SoftDeleteFile(in);
+		}
+		return deleted ? YAFFS_OK : YAFFS_FAIL;
+	} else {
+		/* The file has no data chunks so we toss it immediately */
+		yaffs_FreeTnode(in->myDev, in->variant.fileVariant.top);
+		in->variant.fileVariant.top = NULL;
+		yaffs_DoGenericObjectDeletion(in);
+
+		return YAFFS_OK;
+	}
+}
+
+static int yaffs_IsNonEmptyDirectory(yaffs_Object *obj)
+{
+	return (obj->variantType == YAFFS_OBJECT_TYPE_DIRECTORY) &&
+		!(ylist_empty(&obj->variant.directoryVariant.children));
+}
+
+static int yaffs_DeleteDirectory(yaffs_Object *obj)
+{
+	/* First check that the directory is empty. */
+	if (yaffs_IsNonEmptyDirectory(obj))
+		return YAFFS_FAIL;
+
+	return yaffs_DoGenericObjectDeletion(obj);
+}
+
+static int yaffs_DeleteSymLink(yaffs_Object *in)
+{
+	if(in->variant.symLinkVariant.alias)
+		YFREE(in->variant.symLinkVariant.alias);
+	in->variant.symLinkVariant.alias=NULL;
+
+	return yaffs_DoGenericObjectDeletion(in);
+}
+
+static int yaffs_DeleteHardLink(yaffs_Object *in)
+{
+	/* remove this hardlink from the list assocaited with the equivalent
+	 * object
+	 */
+	ylist_del_init(&in->hardLinks);
+	return yaffs_DoGenericObjectDeletion(in);
+}
+
+int yaffs_DeleteObject(yaffs_Object *obj)
+{
+int retVal = -1;
+	switch (obj->variantType) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		retVal = yaffs_DeleteFile(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_DIRECTORY:
+		if(!ylist_empty(&obj->variant.directoryVariant.dirty)){
+			T(YAFFS_TRACE_BACKGROUND, (TSTR("Remove object %d from dirty directories" TENDSTR),obj->objectId));
+			ylist_del_init(&obj->variant.directoryVariant.dirty);
+		}
+		return yaffs_DeleteDirectory(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		retVal = yaffs_DeleteSymLink(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_HARDLINK:
+		retVal = yaffs_DeleteHardLink(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_SPECIAL:
+		retVal = yaffs_DoGenericObjectDeletion(obj);
+		break;
+	case YAFFS_OBJECT_TYPE_UNKNOWN:
+		retVal = 0;
+		break;		/* should not happen. */
+	}
+
+	return retVal;
+}
+
+static int yaffs_UnlinkWorker(yaffs_Object *obj)
+{
+
+	int immediateDeletion = 0;
+
+	if (!obj->myInode)
+		immediateDeletion = 1;
+
+	if(obj)
+		yaffs_UpdateParent(obj->parent);
+
+	if (obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
+		return yaffs_DeleteHardLink(obj);
+	} else if (!ylist_empty(&obj->hardLinks)) {
+		/* Curve ball: We're unlinking an object that has a hardlink.
+		 *
+		 * This problem arises because we are not strictly following
+		 * The Linux link/inode model.
+		 *
+		 * We can't really delete the object.
+		 * Instead, we do the following:
+		 * - Select a hardlink.
+		 * - Unhook it from the hard links
+		 * - Move it from its parent directory (so that the rename can work)
+		 * - Rename the object to the hardlink's name.
+		 * - Delete the hardlink
+		 */
+
+		yaffs_Object *hl;
+		yaffs_Object *parent;
+		int retVal;
+		YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
+
+		hl = ylist_entry(obj->hardLinks.next, yaffs_Object, hardLinks);
+
+		yaffs_GetObjectName(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
+		parent = hl->parent;
+
+		ylist_del_init(&hl->hardLinks);
+
+ 		yaffs_AddObjectToDirectory(obj->myDev->unlinkedDir, hl);
+
+		retVal = yaffs_ChangeObjectName(obj,parent, name, 0, 0);
+
+		if (retVal == YAFFS_OK)
+			retVal = yaffs_DoGenericObjectDeletion(hl);
+
+		return retVal;
+
+	} else if (immediateDeletion) {
+		switch (obj->variantType) {
+		case YAFFS_OBJECT_TYPE_FILE:
+			return yaffs_DeleteFile(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_DIRECTORY:
+			ylist_del_init(&obj->variant.directoryVariant.dirty);
+			return yaffs_DeleteDirectory(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_SYMLINK:
+			return yaffs_DeleteSymLink(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_SPECIAL:
+			return yaffs_DoGenericObjectDeletion(obj);
+			break;
+		case YAFFS_OBJECT_TYPE_HARDLINK:
+		case YAFFS_OBJECT_TYPE_UNKNOWN:
+		default:
+			return YAFFS_FAIL;
+		}
+	} else if(yaffs_IsNonEmptyDirectory(obj))
+		return YAFFS_FAIL;
+	else
+		return yaffs_ChangeObjectName(obj, obj->myDev->unlinkedDir,
+					   _Y("unlinked"), 0, 0);
+}
+
+
+static int yaffs_UnlinkObject(yaffs_Object *obj)
+{
+
+	if (obj && obj->unlinkAllowed)
+		return yaffs_UnlinkWorker(obj);
+
+	return YAFFS_FAIL;
+
+}
+int yaffs_Unlink(yaffs_Object *dir, const YCHAR *name)
+{
+	yaffs_Object *obj;
+
+	obj = yaffs_FindObjectByName(dir, name);
+	return yaffs_UnlinkObject(obj);
+}
+
+/*----------------------- Initialisation Scanning ---------------------- */
+
+static void yaffs_HandleShadowedObject(yaffs_Device *dev, int objId,
+				int backwardScanning)
+{
+	yaffs_Object *obj;
+
+	if (!backwardScanning) {
+		/* Handle YAFFS1 forward scanning case
+		 * For YAFFS1 we always do the deletion
+		 */
+
+	} else {
+		/* Handle YAFFS2 case (backward scanning)
+		 * If the shadowed object exists then ignore.
+		 */
+		obj = yaffs_FindObjectByNumber(dev, objId);
+		if(obj)
+			return;
+	}
+
+	/* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
+	 * We put it in unlinked dir to be cleaned up after the scanning
+	 */
+	obj =
+	    yaffs_FindOrCreateObjectByNumber(dev, objId,
+					     YAFFS_OBJECT_TYPE_FILE);
+	if (!obj)
+		return;
+	obj->isShadowed = 1;
+	yaffs_AddObjectToDirectory(dev->unlinkedDir, obj);
+	obj->variant.fileVariant.shrinkSize = 0;
+	obj->valid = 1;		/* So that we don't read any other info for this file */
+
+}
+
+typedef struct {
+	int seq;
+	int block;
+} yaffs_BlockIndex;
+
+
+static void yaffs_HardlinkFixup(yaffs_Device *dev, yaffs_Object *hardList)
+{
+	yaffs_Object *hl;
+	yaffs_Object *in;
+
+	while (hardList) {
+		hl = hardList;
+		hardList = (yaffs_Object *) (hardList->hardLinks.next);
+
+		in = yaffs_FindObjectByNumber(dev,
+					      hl->variant.hardLinkVariant.
+					      equivalentObjectId);
+
+		if (in) {
+			/* Add the hardlink pointers */
+			hl->variant.hardLinkVariant.equivalentObject = in;
+			ylist_add(&hl->hardLinks, &in->hardLinks);
+		} else {
+			/* Todo Need to report/handle this better.
+			 * Got a problem... hardlink to a non-existant object
+			 */
+			hl->variant.hardLinkVariant.equivalentObject = NULL;
+			YINIT_LIST_HEAD(&hl->hardLinks);
+
+		}
+	}
+}
+
+
+
+
+
+static int ybicmp(const void *a, const void *b)
+{
+	register int aseq = ((yaffs_BlockIndex *)a)->seq;
+	register int bseq = ((yaffs_BlockIndex *)b)->seq;
+	register int ablock = ((yaffs_BlockIndex *)a)->block;
+	register int bblock = ((yaffs_BlockIndex *)b)->block;
+	if (aseq == bseq)
+		return ablock - bblock;
+	else
+		return aseq - bseq;
+}
+
+
+struct yaffs_ShadowFixerStruct {
+	int objectId;
+	int shadowedId;
+	struct yaffs_ShadowFixerStruct *next;
+};
+
+
+static void yaffs_StripDeletedObjects(yaffs_Device *dev)
+{
+	/*
+	*  Sort out state of unlinked and deleted objects after scanning.
+	*/
+	struct ylist_head *i;
+	struct ylist_head *n;
+	yaffs_Object *l;
+
+	/* Soft delete all the unlinked files */
+	ylist_for_each_safe(i, n,
+		&dev->unlinkedDir->variant.directoryVariant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_Object, siblings);
+			yaffs_DeleteObject(l);
+		}
+	}
+
+	ylist_for_each_safe(i, n,
+		&dev->deletedDir->variant.directoryVariant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_Object, siblings);
+			yaffs_DeleteObject(l);
+		}
+	}
+
+}
+
+/*
+ * This code iterates through all the objects making sure that they are rooted.
+ * Any unrooted objects are re-rooted in lost+found.
+ * An object needs to be in one of:
+ * - Directly under deleted, unlinked
+ * - Directly or indirectly under root.
+ *
+ * Note:
+ *  This code assumes that we don't ever change the current relationships between
+ *  directories:
+ *   rootDir->parent == unlinkedDir->parent == deletedDir->parent == NULL
+ *   lostNfound->parent == rootDir
+ *
+ * This fixes the problem where directories might have inadvertently been deleted
+ * leaving the object "hanging" without being rooted in the directory tree.
+ */
+ 
+static int yaffs_HasNULLParent(yaffs_Device *dev, yaffs_Object *obj)
+{
+	return (obj == dev->deletedDir ||
+		obj == dev->unlinkedDir||
+		obj == dev->rootDir);
+}
+
+static void yaffs_FixHangingObjects(yaffs_Device *dev)
+{
+	yaffs_Object *obj;
+	yaffs_Object *parent;
+	int i;
+	struct ylist_head *lh;
+	struct ylist_head *n;
+	int depthLimit;
+	int hanging;
+
+
+	/* Iterate through the objects in each hash entry,
+	 * looking at each object.
+	 * Make sure it is rooted.
+	 */
+
+	for (i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++) {
+		ylist_for_each_safe(lh, n, &dev->objectBucket[i].list) {
+			if (lh) {
+				obj = ylist_entry(lh, yaffs_Object, hashLink);
+				parent= obj->parent;
+				
+				if(yaffs_HasNULLParent(dev,obj)){
+					/* These directories are not hanging */
+					hanging = 0;
+				}
+				else if(!parent || parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
+					hanging = 1;
+				else if(yaffs_HasNULLParent(dev,parent))
+					hanging = 0;
+				else {
+					/*
+					 * Need to follow the parent chain to see if it is hanging.
+					 */
+					hanging = 0;
+					depthLimit=100;
+
+					while(parent != dev->rootDir &&
+						parent->parent &&
+						parent->parent->variantType == YAFFS_OBJECT_TYPE_DIRECTORY &&
+						depthLimit > 0){
+						parent = parent->parent;
+						depthLimit--;
+					}
+					if(parent != dev->rootDir)
+						hanging = 1;
+				}
+				if(hanging){
+					T(YAFFS_TRACE_SCAN,
+					  (TSTR("Hanging object %d moved to lost and found" TENDSTR),
+					  	obj->objectId));
+					yaffs_AddObjectToDirectory(dev->lostNFoundDir,obj);
+				}
+			}
+		}
+	}
+}
+
+
+/*
+ * Delete directory contents for cleaning up lost and found.
+ */
+static void yaffs_DeleteDirectoryContents(yaffs_Object *dir)
+{
+	yaffs_Object *obj;
+	struct ylist_head *lh;
+	struct ylist_head *n;
+
+	if(dir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY)
+		YBUG();
+	
+	ylist_for_each_safe(lh, n, &dir->variant.directoryVariant.children) {
+		if (lh) {
+			obj = ylist_entry(lh, yaffs_Object, siblings);
+			if(obj->variantType == YAFFS_OBJECT_TYPE_DIRECTORY)
+				yaffs_DeleteDirectoryContents(obj);
+
+			T(YAFFS_TRACE_SCAN,
+				(TSTR("Deleting lost_found object %d" TENDSTR),
+				obj->objectId));
+
+			/* Need to use UnlinkObject since Delete would not handle
+			 * hardlinked objects correctly.
+			 */
+			yaffs_UnlinkObject(obj); 
+		}
+	}
+			
+}
+
+static void yaffs_EmptyLostAndFound(yaffs_Device *dev)
+{
+	yaffs_DeleteDirectoryContents(dev->lostNFoundDir);
+}
+
+static int yaffs_Scan(yaffs_Device *dev)
+{
+	yaffs_ExtendedTags tags;
+	int blk;
+	int blockIterator;
+	int startIterator;
+	int endIterator;
+	int result;
+
+	int chunk;
+	int c;
+	int deleted;
+	yaffs_BlockState state;
+	yaffs_Object *hardList = NULL;
+	yaffs_BlockInfo *bi;
+	__u32 sequenceNumber;
+	yaffs_ObjectHeader *oh;
+	yaffs_Object *in;
+	yaffs_Object *parent;
+
+	int alloc_failed = 0;
+
+	struct yaffs_ShadowFixerStruct *shadowFixerList = NULL;
+
+
+	__u8 *chunkData;
+
+
+
+	T(YAFFS_TRACE_SCAN,
+	  (TSTR("yaffs_Scan starts  intstartblk %d intendblk %d..." TENDSTR),
+	   dev->internalStartBlock, dev->internalEndBlock));
+
+	chunkData = yaffs_GetTempBuffer(dev, __LINE__);
+
+	dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
+
+	/* Scan all the blocks to determine their state */
+	bi = dev->blockInfo;
+	for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
+		yaffs_ClearChunkBits(dev, blk);
+		bi->pagesInUse = 0;
+		bi->softDeletions = 0;
+
+		yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
+
+		bi->blockState = state;
+		bi->sequenceNumber = sequenceNumber;
+
+		if (bi->sequenceNumber == YAFFS_SEQUENCE_BAD_BLOCK)
+			bi->blockState = state = YAFFS_BLOCK_STATE_DEAD;
+
+		T(YAFFS_TRACE_SCAN_DEBUG,
+		  (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
+		   state, sequenceNumber));
+
+		if (state == YAFFS_BLOCK_STATE_DEAD) {
+			T(YAFFS_TRACE_BAD_BLOCKS,
+			  (TSTR("block %d is bad" TENDSTR), blk));
+		} else if (state == YAFFS_BLOCK_STATE_EMPTY) {
+			T(YAFFS_TRACE_SCAN_DEBUG,
+			  (TSTR("Block empty " TENDSTR)));
+			dev->nErasedBlocks++;
+			dev->nFreeChunks += dev->param.nChunksPerBlock;
+		}
+		bi++;
+	}
+
+	startIterator = dev->internalStartBlock;
+	endIterator = dev->internalEndBlock;
+
+	/* For each block.... */
+	for (blockIterator = startIterator; !alloc_failed && blockIterator <= endIterator;
+	     blockIterator++) {
+
+		YYIELD();
+
+		YYIELD();
+
+		blk = blockIterator;
+
+		bi = yaffs_GetBlockInfo(dev, blk);
+		state = bi->blockState;
+
+		deleted = 0;
+
+		/* For each chunk in each block that needs scanning....*/
+		for (c = 0; !alloc_failed && c < dev->param.nChunksPerBlock &&
+		     state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
+			/* Read the tags and decide what to do */
+			chunk = blk * dev->param.nChunksPerBlock + c;
+
+			result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
+							&tags);
+
+			/* Let's have a good look at this chunk... */
+
+			if (tags.eccResult == YAFFS_ECC_RESULT_UNFIXED || tags.chunkDeleted) {
+				/* YAFFS1 only...
+				 * A deleted chunk
+				 */
+				deleted++;
+				dev->nFreeChunks++;
+				/*T((" %d %d deleted\n",blk,c)); */
+			} else if (!tags.chunkUsed) {
+				/* An unassigned chunk in the block
+				 * This means that either the block is empty or
+				 * this is the one being allocated from
+				 */
+
+				if (c == 0) {
+					/* We're looking at the first chunk in the block so the block is unused */
+					state = YAFFS_BLOCK_STATE_EMPTY;
+					dev->nErasedBlocks++;
+				} else {
+					/* this is the block being allocated from */
+					T(YAFFS_TRACE_SCAN,
+					  (TSTR
+					   (" Allocating from %d %d" TENDSTR),
+					   blk, c));
+					state = YAFFS_BLOCK_STATE_ALLOCATING;
+					dev->allocationBlock = blk;
+					dev->allocationPage = c;
+					dev->allocationBlockFinder = blk;
+					/* Set block finder here to encourage the allocator to go forth from here. */
+
+				}
+
+				dev->nFreeChunks += (dev->param.nChunksPerBlock - c);
+			} else if (tags.chunkId > 0) {
+				/* chunkId > 0 so it is a data chunk... */
+				unsigned int endpos;
+
+				yaffs_SetChunkBit(dev, blk, c);
+				bi->pagesInUse++;
+
+				in = yaffs_FindOrCreateObjectByNumber(dev,
+								      tags.
+								      objectId,
+								      YAFFS_OBJECT_TYPE_FILE);
+				/* PutChunkIntoFile checks for a clash (two data chunks with
+				 * the same chunkId).
+				 */
+
+				if (!in)
+					alloc_failed = 1;
+
+				if (in) {
+					if (!yaffs_PutChunkIntoFile(in, tags.chunkId, chunk, 1))
+						alloc_failed = 1;
+				}
+
+				endpos =
+				    (tags.chunkId - 1) * dev->nDataBytesPerChunk +
+				    tags.byteCount;
+				if (in &&
+				    in->variantType == YAFFS_OBJECT_TYPE_FILE
+				    && in->variant.fileVariant.scannedFileSize <
+				    endpos) {
+					in->variant.fileVariant.
+					    scannedFileSize = endpos;
+					if (!dev->param.useHeaderFileSize) {
+						in->variant.fileVariant.
+						    fileSize =
+						    in->variant.fileVariant.
+						    scannedFileSize;
+					}
+
+				}
+				/* T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId));   */
+			} else {
+				/* chunkId == 0, so it is an ObjectHeader.
+				 * Thus, we read in the object header and make the object
+				 */
+				yaffs_SetChunkBit(dev, blk, c);
+				bi->pagesInUse++;
+
+				result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
+								chunkData,
+								NULL);
+
+				oh = (yaffs_ObjectHeader *) chunkData;
+
+				in = yaffs_FindObjectByNumber(dev,
+							      tags.objectId);
+				if (in && in->variantType != oh->type) {
+					/* This should not happen, but somehow
+					 * Wev'e ended up with an objectId that has been reused but not yet
+					 * deleted, and worse still it has changed type. Delete the old object.
+					 */
+
+					yaffs_DeleteObject(in);
+
+					in = 0;
+				}
+
+				in = yaffs_FindOrCreateObjectByNumber(dev,
+								      tags.
+								      objectId,
+								      oh->type);
+
+				if (!in)
+					alloc_failed = 1;
+
+				if (in && oh->shadowsObject > 0) {
+
+					struct yaffs_ShadowFixerStruct *fixer;
+					fixer = YMALLOC(sizeof(struct yaffs_ShadowFixerStruct));
+					if (fixer) {
+						fixer->next = shadowFixerList;
+						shadowFixerList = fixer;
+						fixer->objectId = tags.objectId;
+						fixer->shadowedId = oh->shadowsObject;
+					}
+
+				}
+
+				if (in && in->valid) {
+					/* We have already filled this one. We have a duplicate and need to resolve it. */
+
+					unsigned existingSerial = in->serial;
+					unsigned newSerial = tags.serialNumber;
+
+					if (((existingSerial + 1) & 3) == newSerial) {
+						/* Use new one - destroy the exisiting one */
+						yaffs_DeleteChunk(dev,
+								  in->hdrChunk,
+								  1, __LINE__);
+						in->valid = 0;
+					} else {
+						/* Use existing - destroy this one. */
+						yaffs_DeleteChunk(dev, chunk, 1,
+								  __LINE__);
+					}
+				}
+
+				if (in && !in->valid &&
+				    (tags.objectId == YAFFS_OBJECTID_ROOT ||
+				     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND)) {
+					/* We only load some info, don't fiddle with directory structure */
+					in->valid = 1;
+					in->variantType = oh->type;
+
+					in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+					in->win_atime[0] = oh->win_atime[0];
+					in->win_ctime[0] = oh->win_ctime[0];
+					in->win_mtime[0] = oh->win_mtime[0];
+					in->win_atime[1] = oh->win_atime[1];
+					in->win_ctime[1] = oh->win_ctime[1];
+					in->win_mtime[1] = oh->win_mtime[1];
+#else
+					in->yst_uid = oh->yst_uid;
+					in->yst_gid = oh->yst_gid;
+					in->yst_atime = oh->yst_atime;
+					in->yst_mtime = oh->yst_mtime;
+					in->yst_ctime = oh->yst_ctime;
+					in->yst_rdev = oh->yst_rdev;
+#endif
+					in->hdrChunk = chunk;
+					in->serial = tags.serialNumber;
+
+				} else if (in && !in->valid) {
+					/* we need to load this info */
+
+					in->valid = 1;
+					in->variantType = oh->type;
+
+					in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+					in->win_atime[0] = oh->win_atime[0];
+					in->win_ctime[0] = oh->win_ctime[0];
+					in->win_mtime[0] = oh->win_mtime[0];
+					in->win_atime[1] = oh->win_atime[1];
+					in->win_ctime[1] = oh->win_ctime[1];
+					in->win_mtime[1] = oh->win_mtime[1];
+#else
+					in->yst_uid = oh->yst_uid;
+					in->yst_gid = oh->yst_gid;
+					in->yst_atime = oh->yst_atime;
+					in->yst_mtime = oh->yst_mtime;
+					in->yst_ctime = oh->yst_ctime;
+					in->yst_rdev = oh->yst_rdev;
+#endif
+					in->hdrChunk = chunk;
+					in->serial = tags.serialNumber;
+
+					yaffs_SetObjectName(in, oh->name);
+					in->dirty = 0;
+
+					/* directory stuff...
+					 * hook up to parent
+					 */
+
+					parent =
+					    yaffs_FindOrCreateObjectByNumber
+					    (dev, oh->parentObjectId,
+					     YAFFS_OBJECT_TYPE_DIRECTORY);
+					if (!parent)
+						alloc_failed = 1;
+					if (parent && parent->variantType ==
+					    YAFFS_OBJECT_TYPE_UNKNOWN) {
+						/* Set up as a directory */
+						parent->variantType =
+							YAFFS_OBJECT_TYPE_DIRECTORY;
+						YINIT_LIST_HEAD(&parent->variant.
+								directoryVariant.
+								children);
+					} else if (!parent || parent->variantType !=
+						   YAFFS_OBJECT_TYPE_DIRECTORY) {
+						/* Hoosterman, another problem....
+						 * We're trying to use a non-directory as a directory
+						 */
+
+						T(YAFFS_TRACE_ERROR,
+						  (TSTR
+						   ("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found."
+						    TENDSTR)));
+						parent = dev->lostNFoundDir;
+					}
+
+					yaffs_AddObjectToDirectory(parent, in);
+
+					if (0 && (parent == dev->deletedDir ||
+						  parent == dev->unlinkedDir)) {
+						in->deleted = 1;	/* If it is unlinked at start up then it wants deleting */
+						dev->nDeletedFiles++;
+					}
+					/* Note re hardlinks.
+					 * Since we might scan a hardlink before its equivalent object is scanned
+					 * we put them all in a list.
+					 * After scanning is complete, we should have all the objects, so we run through this
+					 * list and fix up all the chains.
+					 */
+
+					switch (in->variantType) {
+					case YAFFS_OBJECT_TYPE_UNKNOWN:
+						/* Todo got a problem */
+						break;
+					case YAFFS_OBJECT_TYPE_FILE:
+						if (dev->param.useHeaderFileSize)
+
+							in->variant.fileVariant.
+							    fileSize =
+							    oh->fileSize;
+
+						break;
+					case YAFFS_OBJECT_TYPE_HARDLINK:
+						in->variant.hardLinkVariant.
+							equivalentObjectId =
+							oh->equivalentObjectId;
+						in->hardLinks.next =
+							(struct ylist_head *)
+							hardList;
+						hardList = in;
+						break;
+					case YAFFS_OBJECT_TYPE_DIRECTORY:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SPECIAL:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SYMLINK:
+						in->variant.symLinkVariant.alias =
+						    yaffs_CloneString(oh->alias);
+						if (!in->variant.symLinkVariant.alias)
+							alloc_failed = 1;
+						break;
+					}
+
+				}
+			}
+		}
+
+		if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+			/* If we got this far while scanning, then the block is fully allocated.*/
+			state = YAFFS_BLOCK_STATE_FULL;
+		}
+
+		if (state == YAFFS_BLOCK_STATE_ALLOCATING) {
+			/* If the block was partially allocated then treat it as fully allocated.*/
+			state = YAFFS_BLOCK_STATE_FULL;
+			dev->allocationBlock = -1;
+		}
+
+		bi->blockState = state;
+
+		/* Now let's see if it was dirty */
+		if (bi->pagesInUse == 0 &&
+		    !bi->hasShrinkHeader &&
+		    bi->blockState == YAFFS_BLOCK_STATE_FULL) {
+			yaffs_BlockBecameDirty(dev, blk);
+		}
+
+	}
+
+
+	/* Ok, we've done all the scanning.
+	 * Fix up the hard link chains.
+	 * We should now have scanned all the objects, now it's time to add these
+	 * hardlinks.
+	 */
+
+	yaffs_HardlinkFixup(dev, hardList);
+
+	/* Fix up any shadowed objects */
+	{
+		struct yaffs_ShadowFixerStruct *fixer;
+		yaffs_Object *obj;
+
+		while (shadowFixerList) {
+			fixer = shadowFixerList;
+			shadowFixerList = fixer->next;
+			/* Complete the rename transaction by deleting the shadowed object
+			 * then setting the object header to unshadowed.
+			 */
+			obj = yaffs_FindObjectByNumber(dev, fixer->shadowedId);
+			if (obj)
+				yaffs_DeleteObject(obj);
+
+			obj = yaffs_FindObjectByNumber(dev, fixer->objectId);
+
+			if (obj)
+				yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0);
+
+			YFREE(fixer);
+		}
+	}
+
+	yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
+
+	if (alloc_failed)
+		return YAFFS_FAIL;
+
+	T(YAFFS_TRACE_SCAN, (TSTR("yaffs_Scan ends" TENDSTR)));
+
+
+	return YAFFS_OK;
+}
+
+static void yaffs_CheckObjectDetailsLoaded(yaffs_Object *in)
+{
+	__u8 *chunkData;
+	yaffs_ObjectHeader *oh;
+	yaffs_Device *dev;
+	yaffs_ExtendedTags tags;
+	int result;
+	int alloc_failed = 0;
+
+	if (!in)
+		return;
+
+	dev = in->myDev;
+
+#if 0
+	T(YAFFS_TRACE_SCAN, (TSTR("details for object %d %s loaded" TENDSTR),
+		in->objectId,
+		in->lazyLoaded ? "not yet" : "already"));
+#endif
+
+	if (in->lazyLoaded && in->hdrChunk > 0) {
+		in->lazyLoaded = 0;
+		chunkData = yaffs_GetTempBuffer(dev, __LINE__);
+
+		result = yaffs_ReadChunkWithTagsFromNAND(dev, in->hdrChunk, chunkData, &tags);
+		oh = (yaffs_ObjectHeader *) chunkData;
+
+		in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+		in->win_atime[0] = oh->win_atime[0];
+		in->win_ctime[0] = oh->win_ctime[0];
+		in->win_mtime[0] = oh->win_mtime[0];
+		in->win_atime[1] = oh->win_atime[1];
+		in->win_ctime[1] = oh->win_ctime[1];
+		in->win_mtime[1] = oh->win_mtime[1];
+#else
+		in->yst_uid = oh->yst_uid;
+		in->yst_gid = oh->yst_gid;
+		in->yst_atime = oh->yst_atime;
+		in->yst_mtime = oh->yst_mtime;
+		in->yst_ctime = oh->yst_ctime;
+		in->yst_rdev = oh->yst_rdev;
+
+#endif
+		yaffs_SetObjectName(in, oh->name);
+
+		if (in->variantType == YAFFS_OBJECT_TYPE_SYMLINK) {
+			in->variant.symLinkVariant.alias =
+						    yaffs_CloneString(oh->alias);
+			if (!in->variant.symLinkVariant.alias)
+				alloc_failed = 1; /* Not returned to caller */
+		}
+
+		yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
+	}
+}
+
+static int yaffs_ScanBackwards(yaffs_Device *dev)
+{
+	yaffs_ExtendedTags tags;
+	int blk;
+	int blockIterator;
+	int startIterator;
+	int endIterator;
+	int nBlocksToScan = 0;
+
+	int chunk;
+	int result;
+	int c;
+	int deleted;
+	yaffs_BlockState state;
+	yaffs_Object *hardList = NULL;
+	yaffs_BlockInfo *bi;
+	__u32 sequenceNumber;
+	yaffs_ObjectHeader *oh;
+	yaffs_Object *in;
+	yaffs_Object *parent;
+	int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
+	int itsUnlinked;
+	__u8 *chunkData;
+
+	int fileSize;
+	int isShrink;
+	int foundChunksInBlock;
+	int equivalentObjectId;
+	int alloc_failed = 0;
+
+
+	yaffs_BlockIndex *blockIndex = NULL;
+	int altBlockIndex = 0;
+
+	if (!dev->param.isYaffs2) {
+		T(YAFFS_TRACE_SCAN,
+		  (TSTR("yaffs_ScanBackwards is only for YAFFS2!" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	T(YAFFS_TRACE_SCAN,
+	  (TSTR
+	   ("yaffs_ScanBackwards starts  intstartblk %d intendblk %d..."
+	    TENDSTR), dev->internalStartBlock, dev->internalEndBlock));
+
+
+	dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
+
+	blockIndex = YMALLOC(nBlocks * sizeof(yaffs_BlockIndex));
+
+	if (!blockIndex) {
+		blockIndex = YMALLOC_ALT(nBlocks * sizeof(yaffs_BlockIndex));
+		altBlockIndex = 1;
+	}
+
+	if (!blockIndex) {
+		T(YAFFS_TRACE_SCAN,
+		  (TSTR("yaffs_Scan() could not allocate block index!" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	dev->blocksInCheckpoint = 0;
+
+	chunkData = yaffs_GetTempBuffer(dev, __LINE__);
+
+	/* Scan all the blocks to determine their state */
+	bi = dev->blockInfo;
+	for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
+		yaffs_ClearChunkBits(dev, blk);
+		bi->pagesInUse = 0;
+		bi->softDeletions = 0;
+
+		yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
+
+		bi->blockState = state;
+		bi->sequenceNumber = sequenceNumber;
+
+		if (bi->sequenceNumber == YAFFS_SEQUENCE_CHECKPOINT_DATA)
+			bi->blockState = state = YAFFS_BLOCK_STATE_CHECKPOINT;
+		if (bi->sequenceNumber == YAFFS_SEQUENCE_BAD_BLOCK)
+			bi->blockState = state = YAFFS_BLOCK_STATE_DEAD;
+
+		T(YAFFS_TRACE_SCAN_DEBUG,
+		  (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
+		   state, sequenceNumber));
+
+
+		if (state == YAFFS_BLOCK_STATE_CHECKPOINT) {
+			dev->blocksInCheckpoint++;
+
+		} else if (state == YAFFS_BLOCK_STATE_DEAD) {
+			T(YAFFS_TRACE_BAD_BLOCKS,
+			  (TSTR("block %d is bad" TENDSTR), blk));
+		} else if (state == YAFFS_BLOCK_STATE_EMPTY) {
+			T(YAFFS_TRACE_SCAN_DEBUG,
+			  (TSTR("Block empty " TENDSTR)));
+			dev->nErasedBlocks++;
+			dev->nFreeChunks += dev->param.nChunksPerBlock;
+		} else if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+
+			/* Determine the highest sequence number */
+			if (sequenceNumber >= YAFFS_LOWEST_SEQUENCE_NUMBER &&
+			    sequenceNumber < YAFFS_HIGHEST_SEQUENCE_NUMBER) {
+
+				blockIndex[nBlocksToScan].seq = sequenceNumber;
+				blockIndex[nBlocksToScan].block = blk;
+
+				nBlocksToScan++;
+
+				if (sequenceNumber >= dev->sequenceNumber)
+					dev->sequenceNumber = sequenceNumber;
+			} else {
+				/* TODO: Nasty sequence number! */
+				T(YAFFS_TRACE_SCAN,
+				  (TSTR
+				   ("Block scanning block %d has bad sequence number %d"
+				    TENDSTR), blk, sequenceNumber));
+
+			}
+		}
+		bi++;
+	}
+
+	T(YAFFS_TRACE_SCAN,
+	(TSTR("%d blocks to be sorted..." TENDSTR), nBlocksToScan));
+
+
+
+	YYIELD();
+
+	/* Sort the blocks */
+#ifndef CONFIG_YAFFS_USE_OWN_SORT
+	{
+		/* Use qsort now. */
+		yaffs_qsort(blockIndex, nBlocksToScan, sizeof(yaffs_BlockIndex), ybicmp);
+	}
+#else
+	{
+		/* Dungy old bubble sort... */
+
+		yaffs_BlockIndex temp;
+		int i;
+		int j;
+
+		for (i = 0; i < nBlocksToScan; i++)
+			for (j = i + 1; j < nBlocksToScan; j++)
+				if (blockIndex[i].seq > blockIndex[j].seq) {
+					temp = blockIndex[j];
+					blockIndex[j] = blockIndex[i];
+					blockIndex[i] = temp;
+				}
+	}
+#endif
+
+	YYIELD();
+
+	T(YAFFS_TRACE_SCAN, (TSTR("...done" TENDSTR)));
+
+	/* Now scan the blocks looking at the data. */
+	startIterator = 0;
+	endIterator = nBlocksToScan - 1;
+	T(YAFFS_TRACE_SCAN_DEBUG,
+	  (TSTR("%d blocks to be scanned" TENDSTR), nBlocksToScan));
+
+	/* For each block.... backwards */
+	for (blockIterator = endIterator; !alloc_failed && blockIterator >= startIterator;
+			blockIterator--) {
+		/* Cooperative multitasking! This loop can run for so
+		   long that watchdog timers expire. */
+		YYIELD();
+
+		/* get the block to scan in the correct order */
+		blk = blockIndex[blockIterator].block;
+
+		bi = yaffs_GetBlockInfo(dev, blk);
+
+
+		state = bi->blockState;
+
+		deleted = 0;
+
+		/* For each chunk in each block that needs scanning.... */
+		foundChunksInBlock = 0;
+		for (c = dev->param.nChunksPerBlock - 1;
+		     !alloc_failed && c >= 0 &&
+		     (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
+		      state == YAFFS_BLOCK_STATE_ALLOCATING); c--) {
+			/* Scan backwards...
+			 * Read the tags and decide what to do
+			 */
+
+			chunk = blk * dev->param.nChunksPerBlock + c;
+
+			result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
+							&tags);
+
+			/* Let's have a good look at this chunk... */
+
+			if (!tags.chunkUsed) {
+				/* An unassigned chunk in the block.
+				 * If there are used chunks after this one, then
+				 * it is a chunk that was skipped due to failing the erased
+				 * check. Just skip it so that it can be deleted.
+				 * But, more typically, We get here when this is an unallocated
+				 * chunk and his means that either the block is empty or
+				 * this is the one being allocated from
+				 */
+
+				if (foundChunksInBlock) {
+					/* This is a chunk that was skipped due to failing the erased check */
+				} else if (c == 0) {
+					/* We're looking at the first chunk in the block so the block is unused */
+					state = YAFFS_BLOCK_STATE_EMPTY;
+					dev->nErasedBlocks++;
+				} else {
+					if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
+					    state == YAFFS_BLOCK_STATE_ALLOCATING) {
+						if (dev->sequenceNumber == bi->sequenceNumber) {
+							/* this is the block being allocated from */
+
+							T(YAFFS_TRACE_SCAN,
+							  (TSTR
+							   (" Allocating from %d %d"
+							    TENDSTR), blk, c));
+
+							state = YAFFS_BLOCK_STATE_ALLOCATING;
+							dev->allocationBlock = blk;
+							dev->allocationPage = c;
+							dev->allocationBlockFinder = blk;
+						} else {
+							/* This is a partially written block that is not
+							 * the current allocation block.
+							 */
+
+							 T(YAFFS_TRACE_SCAN,
+							 (TSTR("Partially written block %d detected" TENDSTR),
+							 blk));
+						}
+					}
+				}
+
+				dev->nFreeChunks++;
+
+			} else if (tags.eccResult == YAFFS_ECC_RESULT_UNFIXED) {
+				T(YAFFS_TRACE_SCAN,
+				  (TSTR(" Unfixed ECC in chunk(%d:%d), chunk ignored"TENDSTR),
+				  blk, c));
+
+				  dev->nFreeChunks++;
+
+			} else if (tags.chunkId > 0) {
+				/* chunkId > 0 so it is a data chunk... */
+				unsigned int endpos;
+				__u32 chunkBase =
+				    (tags.chunkId - 1) * dev->nDataBytesPerChunk;
+
+				foundChunksInBlock = 1;
+
+
+				yaffs_SetChunkBit(dev, blk, c);
+				bi->pagesInUse++;
+
+				in = yaffs_FindOrCreateObjectByNumber(dev,
+								      tags.
+								      objectId,
+								      YAFFS_OBJECT_TYPE_FILE);
+				if (!in) {
+					/* Out of memory */
+					alloc_failed = 1;
+				}
+
+				if (in &&
+				    in->variantType == YAFFS_OBJECT_TYPE_FILE
+				    && chunkBase < in->variant.fileVariant.shrinkSize) {
+					/* This has not been invalidated by a resize */
+					if (!yaffs_PutChunkIntoFile(in, tags.chunkId, chunk, -1)) {
+						alloc_failed = 1;
+					}
+
+					/* File size is calculated by looking at the data chunks if we have not
+					 * seen an object header yet. Stop this practice once we find an object header.
+					 */
+					endpos = chunkBase + tags.byteCount;
+
+					if (!in->valid &&	/* have not got an object header yet */
+					    in->variant.fileVariant.scannedFileSize < endpos) {
+						in->variant.fileVariant.scannedFileSize = endpos;
+						in->variant.fileVariant.fileSize = endpos;
+					}
+
+				} else if (in) {
+					/* This chunk has been invalidated by a resize, or a past file deletion
+					 * so delete the chunk*/
+					yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
+
+				}
+			} else {
+				/* chunkId == 0, so it is an ObjectHeader.
+				 * Thus, we read in the object header and make the object
+				 */
+				foundChunksInBlock = 1;
+
+				yaffs_SetChunkBit(dev, blk, c);
+				bi->pagesInUse++;
+
+				oh = NULL;
+				in = NULL;
+
+				if (tags.extraHeaderInfoAvailable) {
+					in = yaffs_FindOrCreateObjectByNumber(dev,
+						tags.objectId,
+						tags.extraObjectType);
+					if (!in)
+						alloc_failed = 1;
+				}
+
+				if (!in ||
+				    (!in->valid && dev->param.disableLazyLoad) ||
+				    tags.extraShadows ||
+				    (!in->valid &&
+				    (tags.objectId == YAFFS_OBJECTID_ROOT ||
+				     tags.objectId == YAFFS_OBJECTID_LOSTNFOUND))) {
+
+					/* If we don't have  valid info then we need to read the chunk
+					 * TODO In future we can probably defer reading the chunk and
+					 * living with invalid data until needed.
+					 */
+
+					result = yaffs_ReadChunkWithTagsFromNAND(dev,
+									chunk,
+									chunkData,
+									NULL);
+
+					oh = (yaffs_ObjectHeader *) chunkData;
+
+					if (dev->param.inbandTags) {
+						/* Fix up the header if they got corrupted by inband tags */
+						oh->shadowsObject = oh->inbandShadowsObject;
+						oh->isShrink = oh->inbandIsShrink;
+					}
+
+					if (!in) {
+						in = yaffs_FindOrCreateObjectByNumber(dev, tags.objectId, oh->type);
+						if (!in)
+							alloc_failed = 1;
+					}
+
+				}
+
+				if (!in) {
+					/* TODO Hoosterman we have a problem! */
+					T(YAFFS_TRACE_ERROR,
+					  (TSTR
+					   ("yaffs tragedy: Could not make object for object  %d at chunk %d during scan"
+					    TENDSTR), tags.objectId, chunk));
+					continue;
+				}
+
+				if (in->valid) {
+					/* We have already filled this one.
+					 * We have a duplicate that will be discarded, but
+					 * we first have to suck out resize info if it is a file.
+					 */
+
+					if ((in->variantType == YAFFS_OBJECT_TYPE_FILE) &&
+					     ((oh &&
+					       oh->type == YAFFS_OBJECT_TYPE_FILE) ||
+					      (tags.extraHeaderInfoAvailable  &&
+					       tags.extraObjectType == YAFFS_OBJECT_TYPE_FILE))) {
+						__u32 thisSize =
+						    (oh) ? oh->fileSize : tags.
+						    extraFileLength;
+						__u32 parentObjectId =
+						    (oh) ? oh->
+						    parentObjectId : tags.
+						    extraParentObjectId;
+
+
+						isShrink =
+						    (oh) ? oh->isShrink : tags.
+						    extraIsShrinkHeader;
+
+						/* If it is deleted (unlinked at start also means deleted)
+						 * we treat the file size as being zeroed at this point.
+						 */
+						if (parentObjectId ==
+						    YAFFS_OBJECTID_DELETED
+						    || parentObjectId ==
+						    YAFFS_OBJECTID_UNLINKED) {
+							thisSize = 0;
+							isShrink = 1;
+						}
+
+						if (isShrink && in->variant.fileVariant.shrinkSize > thisSize)
+							in->variant.fileVariant.shrinkSize = thisSize;
+
+						if (isShrink)
+							bi->hasShrinkHeader = 1;
+
+					}
+					/* Use existing - destroy this one. */
+					yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
+
+				}
+
+				if (!in->valid && in->variantType !=
+				    (oh ? oh->type : tags.extraObjectType))
+					T(YAFFS_TRACE_ERROR, (
+						TSTR("yaffs tragedy: Bad object type, "
+					    TCONT("%d != %d, for object %d at chunk ")
+					    TCONT("%d during scan")
+						TENDSTR), oh ?
+					    oh->type : tags.extraObjectType,
+					    in->variantType, tags.objectId,
+					    chunk));
+
+				if (!in->valid &&
+				    (tags.objectId == YAFFS_OBJECTID_ROOT ||
+				     tags.objectId ==
+				     YAFFS_OBJECTID_LOSTNFOUND)) {
+					/* We only load some info, don't fiddle with directory structure */
+					in->valid = 1;
+
+					if (oh) {
+						in->variantType = oh->type;
+
+						in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+						in->win_atime[0] = oh->win_atime[0];
+						in->win_ctime[0] = oh->win_ctime[0];
+						in->win_mtime[0] = oh->win_mtime[0];
+						in->win_atime[1] = oh->win_atime[1];
+						in->win_ctime[1] = oh->win_ctime[1];
+						in->win_mtime[1] = oh->win_mtime[1];
+#else
+						in->yst_uid = oh->yst_uid;
+						in->yst_gid = oh->yst_gid;
+						in->yst_atime = oh->yst_atime;
+						in->yst_mtime = oh->yst_mtime;
+						in->yst_ctime = oh->yst_ctime;
+						in->yst_rdev = oh->yst_rdev;
+
+#endif
+					} else {
+						in->variantType = tags.extraObjectType;
+						in->lazyLoaded = 1;
+					}
+
+					in->hdrChunk = chunk;
+
+				} else if (!in->valid) {
+					/* we need to load this info */
+
+					in->valid = 1;
+					in->hdrChunk = chunk;
+
+					if (oh) {
+						in->variantType = oh->type;
+
+						in->yst_mode = oh->yst_mode;
+#ifdef CONFIG_YAFFS_WINCE
+						in->win_atime[0] = oh->win_atime[0];
+						in->win_ctime[0] = oh->win_ctime[0];
+						in->win_mtime[0] = oh->win_mtime[0];
+						in->win_atime[1] = oh->win_atime[1];
+						in->win_ctime[1] = oh->win_ctime[1];
+						in->win_mtime[1] = oh->win_mtime[1];
+#else
+						in->yst_uid = oh->yst_uid;
+						in->yst_gid = oh->yst_gid;
+						in->yst_atime = oh->yst_atime;
+						in->yst_mtime = oh->yst_mtime;
+						in->yst_ctime = oh->yst_ctime;
+						in->yst_rdev = oh->yst_rdev;
+#endif
+
+						if (oh->shadowsObject > 0)
+							yaffs_HandleShadowedObject(dev,
+									   oh->
+									   shadowsObject,
+									   1);
+							
+
+
+						yaffs_SetObjectName(in, oh->name);
+						parent =
+						    yaffs_FindOrCreateObjectByNumber
+							(dev, oh->parentObjectId,
+							 YAFFS_OBJECT_TYPE_DIRECTORY);
+
+						 fileSize = oh->fileSize;
+						 isShrink = oh->isShrink;
+						 equivalentObjectId = oh->equivalentObjectId;
+
+					} else {
+						in->variantType = tags.extraObjectType;
+						parent =
+						    yaffs_FindOrCreateObjectByNumber
+							(dev, tags.extraParentObjectId,
+							 YAFFS_OBJECT_TYPE_DIRECTORY);
+						 fileSize = tags.extraFileLength;
+						 isShrink = tags.extraIsShrinkHeader;
+						 equivalentObjectId = tags.extraEquivalentObjectId;
+						in->lazyLoaded = 1;
+
+					}
+					in->dirty = 0;
+
+					if (!parent)
+						alloc_failed = 1;
+
+					/* directory stuff...
+					 * hook up to parent
+					 */
+
+					if (parent && parent->variantType ==
+					    YAFFS_OBJECT_TYPE_UNKNOWN) {
+						/* Set up as a directory */
+						parent->variantType =
+							YAFFS_OBJECT_TYPE_DIRECTORY;
+						YINIT_LIST_HEAD(&parent->variant.
+							directoryVariant.
+							children);
+					} else if (!parent || parent->variantType !=
+						   YAFFS_OBJECT_TYPE_DIRECTORY) {
+						/* Hoosterman, another problem....
+						 * We're trying to use a non-directory as a directory
+						 */
+
+						T(YAFFS_TRACE_ERROR,
+						  (TSTR
+						   ("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found."
+						    TENDSTR)));
+						parent = dev->lostNFoundDir;
+					}
+
+					yaffs_AddObjectToDirectory(parent, in);
+
+					itsUnlinked = (parent == dev->deletedDir) ||
+						      (parent == dev->unlinkedDir);
+
+					if (isShrink) {
+						/* Mark the block as having a shrinkHeader */
+						bi->hasShrinkHeader = 1;
+					}
+
+					/* Note re hardlinks.
+					 * Since we might scan a hardlink before its equivalent object is scanned
+					 * we put them all in a list.
+					 * After scanning is complete, we should have all the objects, so we run
+					 * through this list and fix up all the chains.
+					 */
+
+					switch (in->variantType) {
+					case YAFFS_OBJECT_TYPE_UNKNOWN:
+						/* Todo got a problem */
+						break;
+					case YAFFS_OBJECT_TYPE_FILE:
+
+						if (in->variant.fileVariant.
+						    scannedFileSize < fileSize) {
+							/* This covers the case where the file size is greater
+							 * than where the data is
+							 * This will happen if the file is resized to be larger
+							 * than its current data extents.
+							 */
+							in->variant.fileVariant.fileSize = fileSize;
+							in->variant.fileVariant.scannedFileSize = fileSize;
+						}
+
+						if (in->variant.fileVariant.shrinkSize > fileSize)
+							in->variant.fileVariant.shrinkSize = fileSize;
+				
+
+						break;
+					case YAFFS_OBJECT_TYPE_HARDLINK:
+						if (!itsUnlinked) {
+							in->variant.hardLinkVariant.equivalentObjectId =
+								equivalentObjectId;
+							in->hardLinks.next =
+								(struct ylist_head *) hardList;
+							hardList = in;
+						}
+						break;
+					case YAFFS_OBJECT_TYPE_DIRECTORY:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SPECIAL:
+						/* Do nothing */
+						break;
+					case YAFFS_OBJECT_TYPE_SYMLINK:
+						if (oh) {
+							in->variant.symLinkVariant.alias =
+								yaffs_CloneString(oh->alias);
+							if (!in->variant.symLinkVariant.alias)
+								alloc_failed = 1;
+						}
+						break;
+					}
+
+				}
+
+			}
+
+		} /* End of scanning for each chunk */
+
+		if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
+			/* If we got this far while scanning, then the block is fully allocated. */
+			state = YAFFS_BLOCK_STATE_FULL;
+		}
+
+
+		bi->blockState = state;
+
+		/* Now let's see if it was dirty */
+		if (bi->pagesInUse == 0 &&
+		    !bi->hasShrinkHeader &&
+		    bi->blockState == YAFFS_BLOCK_STATE_FULL) {
+			yaffs_BlockBecameDirty(dev, blk);
+		}
+
+	}
+	
+	yaffs_SkipRestOfBlock(dev);
+
+	if (altBlockIndex)
+		YFREE_ALT(blockIndex);
+	else
+		YFREE(blockIndex);
+
+	/* Ok, we've done all the scanning.
+	 * Fix up the hard link chains.
+	 * We should now have scanned all the objects, now it's time to add these
+	 * hardlinks.
+	 */
+	yaffs_HardlinkFixup(dev, hardList);
+
+
+	yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
+
+	if (alloc_failed)
+		return YAFFS_FAIL;
+
+	T(YAFFS_TRACE_SCAN, (TSTR("yaffs_ScanBackwards ends" TENDSTR)));
+
+	return YAFFS_OK;
+}
+
+/*------------------------------  Directory Functions ----------------------------- */
+
+static void yaffs_VerifyObjectInDirectory(yaffs_Object *obj)
+{
+	struct ylist_head *lh;
+	yaffs_Object *listObj;
+
+	int count = 0;
+
+	if (!obj) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("No object to verify" TENDSTR)));
+		YBUG();
+		return;
+	}
+
+	if (yaffs_SkipVerification(obj->myDev))
+		return;
+
+	if (!obj->parent) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("Object does not have parent" TENDSTR)));
+		YBUG();
+		return;
+	}
+
+	if (obj->parent->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("Parent is not directory" TENDSTR)));
+		YBUG();
+	}
+
+	/* Iterate through the objects in each hash entry */
+
+	ylist_for_each(lh, &obj->parent->variant.directoryVariant.children) {
+		if (lh) {
+			listObj = ylist_entry(lh, yaffs_Object, siblings);
+			yaffs_VerifyObject(listObj);
+			if (obj == listObj)
+				count++;
+		}
+	 }
+
+	if (count != 1) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("Object in directory %d times" TENDSTR), count));
+		YBUG();
+	}
+}
+
+static void yaffs_VerifyDirectory(yaffs_Object *directory)
+{
+	struct ylist_head *lh;
+	yaffs_Object *listObj;
+
+	if (!directory) {
+		YBUG();
+		return;
+	}
+
+	if (yaffs_SkipFullVerification(directory->myDev))
+		return;
+
+	if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("Directory has wrong type: %d" TENDSTR), directory->variantType));
+		YBUG();
+	}
+
+	/* Iterate through the objects in each hash entry */
+
+	ylist_for_each(lh, &directory->variant.directoryVariant.children) {
+		if (lh) {
+			listObj = ylist_entry(lh, yaffs_Object, siblings);
+			if (listObj->parent != directory) {
+				T(YAFFS_TRACE_ALWAYS, (TSTR("Object in directory list has wrong parent %p" TENDSTR), listObj->parent));
+				YBUG();
+			}
+			yaffs_VerifyObjectInDirectory(listObj);
+		}
+	}
+}
+
+/*
+ *yaffs_UpdateParent() handles fixing a directories mtime and ctime when a new
+ * link (ie. name) is created or deleted in the directory.
+ *
+ * ie.
+ *   create dir/a : update dir's mtime/ctime
+ *   rm dir/a:   update dir's mtime/ctime
+ *   modify dir/a: don't update dir's mtimme/ctime
+ *
+ * This can be handled immediately or defered. Defering helps reduce the number
+ * of updates when many files in a directory are changed within a brief period.
+ *
+ * If the directory updating is defered then yaffs_UpdateDirtyDirecories must be
+ * called periodically.
+ */
+ 
+static void yaffs_UpdateParent(yaffs_Object *obj)
+{
+	yaffs_Device *dev;
+	if(!obj)
+		return;
+
+	dev = obj->myDev;
+	obj->dirty = 1;
+	obj->yst_mtime = obj->yst_ctime = Y_CURRENT_TIME;
+	if(dev->param.deferDirectoryUpdate){
+		struct ylist_head *link = &obj->variant.directoryVariant.dirty; 
+	
+		if(ylist_empty(link)){
+			ylist_add(link,&dev->dirtyDirectories);
+			T(YAFFS_TRACE_BACKGROUND, (TSTR("Added object %d to dirty directories" TENDSTR),obj->objectId));
+		}
+
+	} else
+		yaffs_UpdateObjectHeader(obj,NULL,0,0,0);
+}
+
+void yaffs_UpdateDirtyDirectories(yaffs_Device *dev)
+{
+	struct ylist_head *link;
+	yaffs_Object *obj;
+	yaffs_DirectoryStructure *dS;
+	yaffs_ObjectVariant *oV;
+
+	T(YAFFS_TRACE_BACKGROUND, (TSTR("Update dirty directories" TENDSTR)));
+
+	while(!ylist_empty(&dev->dirtyDirectories)){
+		link = dev->dirtyDirectories.next;
+		ylist_del_init(link);
+		
+		dS=ylist_entry(link,yaffs_DirectoryStructure,dirty);
+		oV = ylist_entry(dS,yaffs_ObjectVariant,directoryVariant);
+		obj = ylist_entry(oV,yaffs_Object,variant);
+
+		T(YAFFS_TRACE_BACKGROUND, (TSTR("Update directory %d" TENDSTR), obj->objectId));
+
+		if(obj->dirty)
+			yaffs_UpdateObjectHeader(obj,NULL,0,0,0);
+	}
+}
+
+static void yaffs_RemoveObjectFromDirectory(yaffs_Object *obj)
+{
+	yaffs_Device *dev = obj->myDev;
+	yaffs_Object *parent;
+
+	yaffs_VerifyObjectInDirectory(obj);
+	parent = obj->parent;
+
+	yaffs_VerifyDirectory(parent);
+
+	if (dev && dev->param.removeObjectCallback)
+		dev->param.removeObjectCallback(obj);
+
+
+	ylist_del_init(&obj->siblings);
+	obj->parent = NULL;
+	
+	yaffs_VerifyDirectory(parent);
+}
+
+static void yaffs_AddObjectToDirectory(yaffs_Object *directory,
+					yaffs_Object *obj)
+{
+	if (!directory) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: Trying to add an object to a null pointer directory"
+		    TENDSTR)));
+		YBUG();
+		return;
+	}
+	if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: Trying to add an object to a non-directory"
+		    TENDSTR)));
+		YBUG();
+	}
+
+	if (obj->siblings.prev == NULL) {
+		/* Not initialised */
+		YBUG();
+	}
+
+
+	yaffs_VerifyDirectory(directory);
+
+	yaffs_RemoveObjectFromDirectory(obj);
+
+
+	/* Now add it */
+	ylist_add(&obj->siblings, &directory->variant.directoryVariant.children);
+	obj->parent = directory;
+
+	if (directory == obj->myDev->unlinkedDir
+			|| directory == obj->myDev->deletedDir) {
+		obj->unlinked = 1;
+		obj->myDev->nUnlinkedFiles++;
+		obj->renameAllowed = 0;
+	}
+
+	yaffs_VerifyDirectory(directory);
+	yaffs_VerifyObjectInDirectory(obj);
+}
+
+yaffs_Object *yaffs_FindObjectByName(yaffs_Object *directory,
+				     const YCHAR *name)
+{
+	int sum;
+
+	struct ylist_head *i;
+	YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
+
+	yaffs_Object *l;
+
+	if (!name)
+		return NULL;
+
+	if (!directory) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_FindObjectByName: null pointer directory"
+		    TENDSTR)));
+		YBUG();
+		return NULL;
+	}
+	if (directory->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
+		YBUG();
+	}
+
+	sum = yaffs_CalcNameSum(name);
+
+	ylist_for_each(i, &directory->variant.directoryVariant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_Object, siblings);
+
+			if (l->parent != directory)
+				YBUG();
+
+			yaffs_CheckObjectDetailsLoaded(l);
+
+			/* Special case for lost-n-found */
+			if (l->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
+				if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0)
+					return l;
+			} else if (yaffs_SumCompare(l->sum, sum) || l->hdrChunk <= 0) {
+				/* LostnFound chunk called Objxxx
+				 * Do a real check
+				 */
+				yaffs_GetObjectName(l, buffer,
+						    YAFFS_MAX_NAME_LENGTH + 1);
+				if (yaffs_strncmp(name, buffer, YAFFS_MAX_NAME_LENGTH) == 0)
+					return l;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+
+#if 0
+int yaffs_ApplyToDirectoryChildren(yaffs_Object *theDir,
+					int (*fn) (yaffs_Object *))
+{
+	struct ylist_head *i;
+	yaffs_Object *l;
+
+	if (!theDir) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_FindObjectByName: null pointer directory"
+		    TENDSTR)));
+		YBUG();
+		return YAFFS_FAIL;
+	}
+	if (theDir->variantType != YAFFS_OBJECT_TYPE_DIRECTORY) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("tragedy: yaffs_FindObjectByName: non-directory" TENDSTR)));
+		YBUG();
+		return YAFFS_FAIL;
+	}
+
+	ylist_for_each(i, &theDir->variant.directoryVariant.children) {
+		if (i) {
+			l = ylist_entry(i, yaffs_Object, siblings);
+			if (l && !fn(l))
+				return YAFFS_FAIL;
+		}
+	}
+
+	return YAFFS_OK;
+
+}
+#endif
+
+/* GetEquivalentObject dereferences any hard links to get to the
+ * actual object.
+ */
+
+yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj)
+{
+	if (obj && obj->variantType == YAFFS_OBJECT_TYPE_HARDLINK) {
+		/* We want the object id of the equivalent object, not this one */
+		obj = obj->variant.hardLinkVariant.equivalentObject;
+		yaffs_CheckObjectDetailsLoaded(obj);
+	}
+	return obj;
+}
+
+int yaffs_GetObjectName(yaffs_Object *obj, YCHAR *name, int buffSize)
+{
+	memset(name, 0, buffSize * sizeof(YCHAR));
+
+	yaffs_CheckObjectDetailsLoaded(obj);
+
+	if (obj->objectId == YAFFS_OBJECTID_LOSTNFOUND) {
+		yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffSize - 1);
+	} else if (obj->hdrChunk <= 0) {
+		YCHAR locName[20];
+		YCHAR numString[20];
+		YCHAR *x = &numString[19];
+		unsigned v = obj->objectId;
+		numString[19] = 0;
+		while (v > 0) {
+			x--;
+			*x = '0' + (v % 10);
+			v /= 10;
+		}
+		/* make up a name */
+		yaffs_strcpy(locName, YAFFS_LOSTNFOUND_PREFIX);
+		yaffs_strcat(locName, x);
+		yaffs_strncpy(name, locName, buffSize - 1);
+
+	}
+#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+	else if (obj->shortName[0])
+		yaffs_strncpy(name, obj->shortName,YAFFS_SHORT_NAME_LENGTH+1);
+#endif
+	else {
+		int result;
+		__u8 *buffer = yaffs_GetTempBuffer(obj->myDev, __LINE__);
+
+		yaffs_ObjectHeader *oh = (yaffs_ObjectHeader *) buffer;
+
+		memset(buffer, 0, obj->myDev->nDataBytesPerChunk);
+
+		if (obj->hdrChunk > 0) {
+			result = yaffs_ReadChunkWithTagsFromNAND(obj->myDev,
+							obj->hdrChunk, buffer,
+							NULL);
+		}
+		yaffs_strncpy(name, oh->name, buffSize - 1);
+		name[buffSize-1]=0;
+
+		yaffs_ReleaseTempBuffer(obj->myDev, buffer, __LINE__);
+	}
+
+	return yaffs_strnlen(name,buffSize-1);
+}
+
+int yaffs_GetObjectFileLength(yaffs_Object *obj)
+{
+	/* Dereference any hard linking */
+	obj = yaffs_GetEquivalentObject(obj);
+
+	if (obj->variantType == YAFFS_OBJECT_TYPE_FILE)
+		return obj->variant.fileVariant.fileSize;
+	if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK){
+		if(!obj->variant.symLinkVariant.alias)
+			return 0;
+		return yaffs_strnlen(obj->variant.symLinkVariant.alias,YAFFS_MAX_ALIAS_LENGTH);
+	} else {
+		/* Only a directory should drop through to here */
+		return obj->myDev->nDataBytesPerChunk;
+	}
+}
+
+int yaffs_GetObjectLinkCount(yaffs_Object *obj)
+{
+	int count = 0;
+	struct ylist_head *i;
+
+	if (!obj->unlinked)
+		count++;		/* the object itself */
+
+	ylist_for_each(i, &obj->hardLinks)
+		count++;		/* add the hard links; */
+
+	return count;
+}
+
+int yaffs_GetObjectInode(yaffs_Object *obj)
+{
+	obj = yaffs_GetEquivalentObject(obj);
+
+	return obj->objectId;
+}
+
+unsigned yaffs_GetObjectType(yaffs_Object *obj)
+{
+	obj = yaffs_GetEquivalentObject(obj);
+
+	switch (obj->variantType) {
+	case YAFFS_OBJECT_TYPE_FILE:
+		return DT_REG;
+		break;
+	case YAFFS_OBJECT_TYPE_DIRECTORY:
+		return DT_DIR;
+		break;
+	case YAFFS_OBJECT_TYPE_SYMLINK:
+		return DT_LNK;
+		break;
+	case YAFFS_OBJECT_TYPE_HARDLINK:
+		return DT_REG;
+		break;
+	case YAFFS_OBJECT_TYPE_SPECIAL:
+		if (S_ISFIFO(obj->yst_mode))
+			return DT_FIFO;
+		if (S_ISCHR(obj->yst_mode))
+			return DT_CHR;
+		if (S_ISBLK(obj->yst_mode))
+			return DT_BLK;
+		if (S_ISSOCK(obj->yst_mode))
+			return DT_SOCK;
+	default:
+		return DT_REG;
+		break;
+	}
+}
+
+YCHAR *yaffs_GetSymlinkAlias(yaffs_Object *obj)
+{
+	obj = yaffs_GetEquivalentObject(obj);
+	if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
+		return yaffs_CloneString(obj->variant.symLinkVariant.alias);
+	else
+		return yaffs_CloneString(_Y(""));
+}
+
+#ifndef CONFIG_YAFFS_WINCE
+
+int yaffs_SetAttributes(yaffs_Object *obj, struct iattr *attr)
+{
+	unsigned int valid = attr->ia_valid;
+
+	if (valid & ATTR_MODE)
+		obj->yst_mode = attr->ia_mode;
+	if (valid & ATTR_UID)
+		obj->yst_uid = attr->ia_uid;
+	if (valid & ATTR_GID)
+		obj->yst_gid = attr->ia_gid;
+
+	if (valid & ATTR_ATIME)
+		obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
+	if (valid & ATTR_CTIME)
+		obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
+	if (valid & ATTR_MTIME)
+		obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
+
+	if (valid & ATTR_SIZE)
+		yaffs_ResizeFile(obj, attr->ia_size);
+
+	yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0);
+
+	return YAFFS_OK;
+
+}
+int yaffs_GetAttributes(yaffs_Object *obj, struct iattr *attr)
+{
+	unsigned int valid = 0;
+
+	attr->ia_mode = obj->yst_mode;
+	valid |= ATTR_MODE;
+	attr->ia_uid = obj->yst_uid;
+	valid |= ATTR_UID;
+	attr->ia_gid = obj->yst_gid;
+	valid |= ATTR_GID;
+
+	Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
+	valid |= ATTR_ATIME;
+	Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
+	valid |= ATTR_CTIME;
+	Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
+	valid |= ATTR_MTIME;
+
+	attr->ia_size = yaffs_GetFileSize(obj);
+	valid |= ATTR_SIZE;
+
+	attr->ia_valid = valid;
+
+	return YAFFS_OK;
+}
+
+#endif
+
+#if 0
+int yaffs_DumpObject(yaffs_Object *obj)
+{
+	YCHAR name[257];
+
+	yaffs_GetObjectName(obj, name, YAFFS_MAX_NAME_LENGTH + 1);
+
+	T(YAFFS_TRACE_ALWAYS,
+	  (TSTR
+	   ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
+	    " chunk %d type %d size %d\n"
+	    TENDSTR), obj->objectId, yaffs_GetObjectInode(obj), name,
+	   obj->dirty, obj->valid, obj->serial, obj->sum, obj->hdrChunk,
+	   yaffs_GetObjectType(obj), yaffs_GetObjectFileLength(obj)));
+
+	return YAFFS_OK;
+}
+#endif
+
+/*---------------------------- Initialisation code -------------------------------------- */
+
+static int yaffs_CheckDevFunctions(const yaffs_Device *dev)
+{
+
+	/* Common functions, gotta have */
+	if (!dev->param.eraseBlockInNAND || !dev->param.initialiseNAND)
+		return 0;
+
+#ifdef CONFIG_YAFFS_YAFFS2
+
+	/* Can use the "with tags" style interface for yaffs1 or yaffs2 */
+	if (dev->param.writeChunkWithTagsToNAND &&
+	    dev->param.readChunkWithTagsFromNAND &&
+	    !dev->param.writeChunkToNAND &&
+	    !dev->param.readChunkFromNAND &&
+	    dev->param.markNANDBlockBad &&
+	    dev->param.queryNANDBlock)
+		return 1;
+#endif
+
+	/* Can use the "spare" style interface for yaffs1 */
+	if (!dev->param.isYaffs2 &&
+	    !dev->param.writeChunkWithTagsToNAND &&
+	    !dev->param.readChunkWithTagsFromNAND &&
+	    dev->param.writeChunkToNAND &&
+	    dev->param.readChunkFromNAND &&
+	    !dev->param.markNANDBlockBad &&
+	    !dev->param.queryNANDBlock)
+		return 1;
+
+	return 0;	/* bad */
+}
+
+
+static int yaffs_CreateInitialDirectories(yaffs_Device *dev)
+{
+	/* Initialise the unlinked, deleted, root and lost and found directories */
+
+	dev->lostNFoundDir = dev->rootDir =  NULL;
+	dev->unlinkedDir = dev->deletedDir = NULL;
+
+	dev->unlinkedDir =
+	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
+
+	dev->deletedDir =
+	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
+
+	dev->rootDir =
+	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_ROOT,
+				      YAFFS_ROOT_MODE | S_IFDIR);
+	dev->lostNFoundDir =
+	    yaffs_CreateFakeDirectory(dev, YAFFS_OBJECTID_LOSTNFOUND,
+				      YAFFS_LOSTNFOUND_MODE | S_IFDIR);
+
+	if (dev->lostNFoundDir && dev->rootDir && dev->unlinkedDir && dev->deletedDir) {
+		yaffs_AddObjectToDirectory(dev->rootDir, dev->lostNFoundDir);
+		return YAFFS_OK;
+	}
+
+	return YAFFS_FAIL;
+}
+
+int yaffs_GutsInitialise(yaffs_Device *dev)
+{
+	int init_failed = 0;
+	unsigned x;
+	int bits;
+
+	T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_GutsInitialise()" TENDSTR)));
+
+	/* Check stuff that must be set */
+
+	if (!dev) {
+		T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	dev->internalStartBlock = dev->param.startBlock;
+	dev->internalEndBlock = dev->param.endBlock;
+	dev->blockOffset = 0;
+	dev->chunkOffset = 0;
+	dev->nFreeChunks = 0;
+
+	dev->gcBlock = 0;
+
+	if (dev->param.startBlock == 0) {
+		dev->internalStartBlock = dev->param.startBlock + 1;
+		dev->internalEndBlock = dev->param.endBlock + 1;
+		dev->blockOffset = 1;
+		dev->chunkOffset = dev->param.nChunksPerBlock;
+	}
+
+	/* Check geometry parameters. */
+
+	if ((!dev->param.inbandTags && dev->param.isYaffs2 && dev->param.totalBytesPerChunk < 1024) ||
+	    (!dev->param.isYaffs2 && dev->param.totalBytesPerChunk < 512) ||
+	    (dev->param.inbandTags && !dev->param.isYaffs2) ||
+	     dev->param.nChunksPerBlock < 2 ||
+	     dev->param.nReservedBlocks < 2 ||
+	     dev->internalStartBlock <= 0 ||
+	     dev->internalEndBlock <= 0 ||
+	     dev->internalEndBlock <= (dev->internalStartBlock + dev->param.nReservedBlocks + 2)) {	/* otherwise it is too small */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s, inbandTags %d "
+		    TENDSTR), dev->param.totalBytesPerChunk, dev->param.isYaffs2 ? "2" : "", dev->param.inbandTags));
+		return YAFFS_FAIL;
+	}
+
+	if (yaffs_InitialiseNAND(dev) != YAFFS_OK) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* Sort out space for inband tags, if required */
+	if (dev->param.inbandTags)
+		dev->nDataBytesPerChunk = dev->param.totalBytesPerChunk - sizeof(yaffs_PackedTags2TagsPart);
+	else
+		dev->nDataBytesPerChunk = dev->param.totalBytesPerChunk;
+
+	/* Got the right mix of functions? */
+	if (!yaffs_CheckDevFunctions(dev)) {
+		/* Function missing */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR
+		   ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
+
+		return YAFFS_FAIL;
+	}
+
+	/* This is really a compilation check. */
+	if (!yaffs_CheckStructures()) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs_CheckStructures failed\n" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	if (dev->isMounted) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs: device already mounted\n" TENDSTR)));
+		return YAFFS_FAIL;
+	}
+
+	/* Finished with most checks. One or two more checks happen later on too. */
+
+	dev->isMounted = 1;
+
+	/* OK now calculate a few things for the device */
+
+	/*
+	 *  Calculate all the chunk size manipulation numbers:
+	 */
+	x = dev->nDataBytesPerChunk;
+	/* We always use dev->chunkShift and dev->chunkDiv */
+	dev->chunkShift = Shifts(x);
+	x >>= dev->chunkShift;
+	dev->chunkDiv = x;
+	/* We only use chunk mask if chunkDiv is 1 */
+	dev->chunkMask = (1<<dev->chunkShift) - 1;
+
+	/*
+	 * Calculate chunkGroupBits.
+	 * We need to find the next power of 2 > than internalEndBlock
+	 */
+
+	x = dev->param.nChunksPerBlock * (dev->internalEndBlock + 1);
+
+	bits = ShiftsGE(x);
+
+	/* Set up tnode width if wide tnodes are enabled. */
+	if (!dev->param.wideTnodesDisabled) {
+		/* bits must be even so that we end up with 32-bit words */
+		if (bits & 1)
+			bits++;
+		if (bits < 16)
+			dev->tnodeWidth = 16;
+		else
+			dev->tnodeWidth = bits;
+	} else
+		dev->tnodeWidth = 16;
+
+	dev->tnodeMask = (1<<dev->tnodeWidth)-1;
+
+	/* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
+	 * so if the bitwidth of the
+	 * chunk range we're using is greater than 16 we need
+	 * to figure out chunk shift and chunkGroupSize
+	 */
+
+	if (bits <= dev->tnodeWidth)
+		dev->chunkGroupBits = 0;
+	else
+		dev->chunkGroupBits = bits - dev->tnodeWidth;
+
+
+	dev->chunkGroupSize = 1 << dev->chunkGroupBits;
+
+	if (dev->param.nChunksPerBlock < dev->chunkGroupSize) {
+		/* We have a problem because the soft delete won't work if
+		 * the chunk group size > chunks per block.
+		 * This can be remedied by using larger "virtual blocks".
+		 */
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("yaffs: chunk group too large\n" TENDSTR)));
+
+		return YAFFS_FAIL;
+	}
+
+	/* OK, we've finished verifying the device, lets continue with initialisation */
+
+	/* More device initialisation */
+	dev->allGCs = 0;
+	dev->passiveGCs = 0;
+	dev->oldestDirtyGCs = 0;
+	dev->backgroundGCs = 0;
+	dev->gcBlockFinder = 0;
+	dev->bufferedBlock = -1;
+	dev->doingBufferedBlockRewrite = 0;
+	dev->nDeletedFiles = 0;
+	dev->nBackgroundDeletions = 0;
+	dev->nUnlinkedFiles = 0;
+	dev->eccFixed = 0;
+	dev->eccUnfixed = 0;
+	dev->tagsEccFixed = 0;
+	dev->tagsEccUnfixed = 0;
+	dev->nErasureFailures = 0;
+	dev->nErasedBlocks = 0;
+	dev->gcDisable= 0;
+	dev->hasPendingPrioritisedGCs = 1; /* Assume the worst for now, will get fixed on first GC */
+	YINIT_LIST_HEAD(&dev->dirtyDirectories);
+	dev->oldestDirtySequence = 0;
+	dev->oldestDirtyBlock = 0;
+
+	/* Initialise temporary buffers and caches. */
+	if (!yaffs_InitialiseTempBuffers(dev))
+		init_failed = 1;
+
+	dev->srCache = NULL;
+	dev->gcCleanupList = NULL;
+
+
+	if (!init_failed &&
+	    dev->param.nShortOpCaches > 0) {
+		int i;
+		void *buf;
+		int srCacheBytes = dev->param.nShortOpCaches * sizeof(yaffs_ChunkCache);
+
+		if (dev->param.nShortOpCaches > YAFFS_MAX_SHORT_OP_CACHES)
+			dev->param.nShortOpCaches = YAFFS_MAX_SHORT_OP_CACHES;
+
+		dev->srCache =  YMALLOC(srCacheBytes);
+
+		buf = (__u8 *) dev->srCache;
+
+		if (dev->srCache)
+			memset(dev->srCache, 0, srCacheBytes);
+
+		for (i = 0; i < dev->param.nShortOpCaches && buf; i++) {
+			dev->srCache[i].object = NULL;
+			dev->srCache[i].lastUse = 0;
+			dev->srCache[i].dirty = 0;
+			dev->srCache[i].data = buf = YMALLOC_DMA(dev->param.totalBytesPerChunk);
+		}
+		if (!buf)
+			init_failed = 1;
+
+		dev->srLastUse = 0;
+	}
+
+	dev->cacheHits = 0;
+
+	if (!init_failed) {
+		dev->gcCleanupList = YMALLOC(dev->param.nChunksPerBlock * sizeof(__u32));
+		if (!dev->gcCleanupList)
+			init_failed = 1;
+	}
+
+	if (dev->param.isYaffs2)
+		dev->param.useHeaderFileSize = 1;
+
+	if (!init_failed && !yaffs_InitialiseBlocks(dev))
+		init_failed = 1;
+
+	yaffs_InitialiseTnodes(dev);
+	yaffs_InitialiseObjects(dev);
+
+	if (!init_failed && !yaffs_CreateInitialDirectories(dev))
+		init_failed = 1;
+
+
+	if (!init_failed) {
+		/* Now scan the flash. */
+		if (dev->param.isYaffs2) {
+			if (yaffs_CheckpointRestore(dev)) {
+				yaffs_CheckObjectDetailsLoaded(dev->rootDir);
+				T(YAFFS_TRACE_ALWAYS,
+				  (TSTR("yaffs: restored from checkpoint" TENDSTR)));
+			} else {
+
+				/* Clean up the mess caused by an aborted checkpoint load
+				 * and scan backwards.
+				 */
+				yaffs_DeinitialiseBlocks(dev);
+				yaffs_DeinitialiseTnodes(dev);
+				yaffs_DeinitialiseObjects(dev);
+
+
+				dev->nErasedBlocks = 0;
+				dev->nFreeChunks = 0;
+				dev->allocationBlock = -1;
+				dev->allocationPage = -1;
+				dev->nDeletedFiles = 0;
+				dev->nUnlinkedFiles = 0;
+				dev->nBackgroundDeletions = 0;
+
+				if (!init_failed && !yaffs_InitialiseBlocks(dev))
+					init_failed = 1;
+
+				yaffs_InitialiseTnodes(dev);
+				yaffs_InitialiseObjects(dev);
+
+				if (!init_failed && !yaffs_CreateInitialDirectories(dev))
+					init_failed = 1;
+
+				if (!init_failed && !yaffs_ScanBackwards(dev))
+					init_failed = 1;
+			}
+		} else if (!yaffs_Scan(dev))
+				init_failed = 1;
+
+		yaffs_StripDeletedObjects(dev);
+		yaffs_FixHangingObjects(dev);
+		if(dev->param.emptyLostAndFound)
+			yaffs_EmptyLostAndFound(dev);
+	}
+
+	if (init_failed) {
+		/* Clean up the mess */
+		T(YAFFS_TRACE_TRACING,
+		  (TSTR("yaffs: yaffs_GutsInitialise() aborted.\n" TENDSTR)));
+
+		yaffs_Deinitialise(dev);
+		return YAFFS_FAIL;
+	}
+
+	/* Zero out stats */
+	dev->nPageReads = 0;
+	dev->nPageWrites = 0;
+	dev->nBlockErasures = 0;
+	dev->nGCCopies = 0;
+	dev->nRetriedWrites = 0;
+
+	dev->nRetiredBlocks = 0;
+
+	yaffs_VerifyFreeChunks(dev);
+	yaffs_VerifyBlocks(dev);
+
+	/* Clean up any aborted checkpoint data */
+	if(!dev->isCheckpointed && dev->blocksInCheckpoint > 0)
+		yaffs_InvalidateCheckpoint(dev);
+
+	T(YAFFS_TRACE_TRACING,
+	  (TSTR("yaffs: yaffs_GutsInitialise() done.\n" TENDSTR)));
+	return YAFFS_OK;
+
+}
+
+void yaffs_Deinitialise(yaffs_Device *dev)
+{
+	if (dev->isMounted) {
+		int i;
+
+		yaffs_DeinitialiseBlocks(dev);
+		yaffs_DeinitialiseTnodes(dev);
+		yaffs_DeinitialiseObjects(dev);
+		if (dev->param.nShortOpCaches > 0 &&
+		    dev->srCache) {
+
+			for (i = 0; i < dev->param.nShortOpCaches; i++) {
+				if (dev->srCache[i].data)
+					YFREE(dev->srCache[i].data);
+				dev->srCache[i].data = NULL;
+			}
+
+			YFREE(dev->srCache);
+			dev->srCache = NULL;
+		}
+
+		YFREE(dev->gcCleanupList);
+
+		for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
+			YFREE(dev->tempBuffer[i].buffer);
+
+		dev->isMounted = 0;
+
+		if (dev->param.deinitialiseNAND)
+			dev->param.deinitialiseNAND(dev);
+	}
+}
+
+static int yaffs_CountFreeChunks(yaffs_Device *dev)
+{
+	int nFree=0;
+	int b;
+
+	yaffs_BlockInfo *blk;
+
+	blk = dev->blockInfo;
+	for (b = dev->internalStartBlock; b <= dev->internalEndBlock; b++) {
+		switch (blk->blockState) {
+		case YAFFS_BLOCK_STATE_EMPTY:
+		case YAFFS_BLOCK_STATE_ALLOCATING:
+		case YAFFS_BLOCK_STATE_COLLECTING:
+		case YAFFS_BLOCK_STATE_FULL:
+			nFree +=
+			    (dev->param.nChunksPerBlock - blk->pagesInUse +
+			     blk->softDeletions);
+			break;
+		default:
+			break;
+		}
+		blk++;
+	}
+
+	return nFree;
+}
+
+int yaffs_GetNumberOfFreeChunks(yaffs_Device *dev)
+{
+	/* This is what we report to the outside world */
+
+	int nFree;
+	int nDirtyCacheChunks;
+	int blocksForCheckpoint;
+	int i;
+
+#if 1
+	nFree = dev->nFreeChunks;
+#else
+	nFree = yaffs_CountFreeChunks(dev);
+#endif
+
+	nFree += dev->nDeletedFiles;
+
+	/* Now count the number of dirty chunks in the cache and subtract those */
+
+	for (nDirtyCacheChunks = 0, i = 0; i < dev->param.nShortOpCaches; i++) {
+		if (dev->srCache[i].dirty)
+			nDirtyCacheChunks++;
+	}
+
+	nFree -= nDirtyCacheChunks;
+
+	nFree -= ((dev->param.nReservedBlocks + 1) * dev->param.nChunksPerBlock);
+
+	/* Now we figure out how much to reserve for the checkpoint and report that... */
+	blocksForCheckpoint = yaffs_CalcCheckpointBlocksRequired(dev) - dev->blocksInCheckpoint;
+	if (blocksForCheckpoint < 0)
+		blocksForCheckpoint = 0;
+
+	nFree -= (blocksForCheckpoint * dev->param.nChunksPerBlock);
+
+	if (nFree < 0)
+		nFree = 0;
+
+	return nFree;
+
+}
+
+static int yaffs_freeVerificationFailures;
+
+static void yaffs_VerifyFreeChunks(yaffs_Device *dev)
+{
+	int counted;
+	int difference;
+
+	if (yaffs_SkipVerification(dev))
+		return;
+
+	counted = yaffs_CountFreeChunks(dev);
+
+	difference = dev->nFreeChunks - counted;
+
+	if (difference) {
+		T(YAFFS_TRACE_ALWAYS,
+		  (TSTR("Freechunks verification failure %d %d %d" TENDSTR),
+		   dev->nFreeChunks, counted, difference));
+		yaffs_freeVerificationFailures++;
+	}
+}
+
+/*---------------------------------------- YAFFS test code ----------------------*/
+
+#define yaffs_CheckStruct(structure, syze, name) \
+	do { \
+		if (sizeof(structure) != syze) { \
+			T(YAFFS_TRACE_ALWAYS, (TSTR("%s should be %d but is %d\n" TENDSTR),\
+				name, syze, (int) sizeof(structure))); \
+			return YAFFS_FAIL; \
+		} \
+	} while (0)
+
+static int yaffs_CheckStructures(void)
+{
+/*      yaffs_CheckStruct(yaffs_Tags,8,"yaffs_Tags"); */
+/*      yaffs_CheckStruct(yaffs_TagsUnion,8,"yaffs_TagsUnion"); */
+/*      yaffs_CheckStruct(yaffs_Spare,16,"yaffs_Spare"); */
+#ifndef CONFIG_YAFFS_TNODE_LIST_DEBUG
+/*	yaffs_CheckStruct(yaffs_Tnode, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_Tnode"); */
+#endif
+#ifndef CONFIG_YAFFS_WINCE
+	yaffs_CheckStruct(yaffs_ObjectHeader, 512, "yaffs_ObjectHeader");
+#endif
+	return YAFFS_OK;
+}
diff --git a/fs/yaffs2/yaffs_guts.h b/fs/yaffs2/yaffs_guts.h
new file mode 100644
index 00000000000..3647d6bce6c
--- /dev/null
+++ b/fs/yaffs2/yaffs_guts.h
@@ -0,0 +1,919 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_GUTS_H__
+#define __YAFFS_GUTS_H__
+
+#include "devextras.h"
+#include "yportenv.h"
+
+#define YAFFS_OK	1
+#define YAFFS_FAIL  0
+
+/* Give us a  Y=0x59,
+ * Give us an A=0x41,
+ * Give us an FF=0xFF
+ * Give us an S=0x53
+ * And what have we got...
+ */
+#define YAFFS_MAGIC			0x5941FF53
+
+#define YAFFS_NTNODES_LEVEL0	  	16
+#define YAFFS_TNODES_LEVEL0_BITS	4
+#define YAFFS_TNODES_LEVEL0_MASK	0xf
+
+#define YAFFS_NTNODES_INTERNAL 		(YAFFS_NTNODES_LEVEL0 / 2)
+#define YAFFS_TNODES_INTERNAL_BITS 	(YAFFS_TNODES_LEVEL0_BITS - 1)
+#define YAFFS_TNODES_INTERNAL_MASK	0x7
+#define YAFFS_TNODES_MAX_LEVEL		6
+
+#ifndef CONFIG_YAFFS_NO_YAFFS1
+#define YAFFS_BYTES_PER_SPARE		16
+#define YAFFS_BYTES_PER_CHUNK		512
+#define YAFFS_CHUNK_SIZE_SHIFT		9
+#define YAFFS_CHUNKS_PER_BLOCK		32
+#define YAFFS_BYTES_PER_BLOCK		(YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
+#endif
+
+#define YAFFS_MIN_YAFFS2_CHUNK_SIZE 	1024
+#define YAFFS_MIN_YAFFS2_SPARE_SIZE	32
+
+#define YAFFS_MAX_CHUNK_ID		0x000FFFFF
+
+#define YAFFS_UNUSED_OBJECT_ID		0x0003FFFF
+
+#define YAFFS_ALLOCATION_NOBJECTS	100
+#define YAFFS_ALLOCATION_NTNODES	100
+#define YAFFS_ALLOCATION_NLINKS		100
+
+#define YAFFS_NOBJECT_BUCKETS		256
+
+
+#define YAFFS_OBJECT_SPACE		0x40000
+
+#define YAFFS_CHECKPOINT_VERSION 	4
+
+#ifdef CONFIG_YAFFS_UNICODE
+#define YAFFS_MAX_NAME_LENGTH		127
+#define YAFFS_MAX_ALIAS_LENGTH		79
+#else
+#define YAFFS_MAX_NAME_LENGTH		255
+#define YAFFS_MAX_ALIAS_LENGTH		159
+#endif
+
+#define YAFFS_SHORT_NAME_LENGTH		15
+
+/* Some special object ids for pseudo objects */
+#define YAFFS_OBJECTID_ROOT		1
+#define YAFFS_OBJECTID_LOSTNFOUND	2
+#define YAFFS_OBJECTID_UNLINKED		3
+#define YAFFS_OBJECTID_DELETED		4
+
+/* Pseudo object ids for checkpointing */
+#define YAFFS_OBJECTID_SB_HEADER	0x10
+#define YAFFS_OBJECTID_CHECKPOINT_DATA	0x20
+#define YAFFS_SEQUENCE_CHECKPOINT_DATA  0x21
+
+
+#define YAFFS_MAX_SHORT_OP_CACHES	20
+
+#define YAFFS_N_TEMP_BUFFERS		6
+
+/* We limit the number attempts at sucessfully saving a chunk of data.
+ * Small-page devices have 32 pages per block; large-page devices have 64.
+ * Default to something in the order of 5 to 10 blocks worth of chunks.
+ */
+#define YAFFS_WR_ATTEMPTS		(5*64)
+
+/* Sequence numbers are used in YAFFS2 to determine block allocation order.
+ * The range is limited slightly to help distinguish bad numbers from good.
+ * This also allows us to perhaps in the future use special numbers for
+ * special purposes.
+ * EFFFFF00 allows the allocation of 8 blocks per second (~1Mbytes) for 15 years,
+ * and is a larger number than the lifetime of a 2GB device.
+ */
+#define YAFFS_LOWEST_SEQUENCE_NUMBER	0x00001000
+#define YAFFS_HIGHEST_SEQUENCE_NUMBER	0xEFFFFF00
+
+/* Special sequence number for bad block that failed to be marked bad */
+#define YAFFS_SEQUENCE_BAD_BLOCK	0xFFFF0000
+
+/* ChunkCache is used for short read/write operations.*/
+typedef struct {
+	struct yaffs_ObjectStruct *object;
+	int chunkId;
+	int lastUse;
+	int dirty;
+	int nBytes;		/* Only valid if the cache is dirty */
+	int locked;		/* Can't push out or flush while locked. */
+	__u8 *data;
+} yaffs_ChunkCache;
+
+
+
+/* Tags structures in RAM
+ * NB This uses bitfield. Bitfields should not straddle a u32 boundary otherwise
+ * the structure size will get blown out.
+ */
+
+#ifndef CONFIG_YAFFS_NO_YAFFS1
+typedef struct {
+	unsigned chunkId:20;
+	unsigned serialNumber:2;
+	unsigned byteCountLSB:10;
+	unsigned objectId:18;
+	unsigned ecc:12;
+	unsigned byteCountMSB:2;
+} yaffs_Tags;
+
+typedef union {
+	yaffs_Tags asTags;
+	__u8 asBytes[8];
+} yaffs_TagsUnion;
+
+#endif
+
+/* Stuff used for extended tags in YAFFS2 */
+
+typedef enum {
+	YAFFS_ECC_RESULT_UNKNOWN,
+	YAFFS_ECC_RESULT_NO_ERROR,
+	YAFFS_ECC_RESULT_FIXED,
+	YAFFS_ECC_RESULT_UNFIXED
+} yaffs_ECCResult;
+
+typedef enum {
+	YAFFS_OBJECT_TYPE_UNKNOWN,
+	YAFFS_OBJECT_TYPE_FILE,
+	YAFFS_OBJECT_TYPE_SYMLINK,
+	YAFFS_OBJECT_TYPE_DIRECTORY,
+	YAFFS_OBJECT_TYPE_HARDLINK,
+	YAFFS_OBJECT_TYPE_SPECIAL
+} yaffs_ObjectType;
+
+#define YAFFS_OBJECT_TYPE_MAX YAFFS_OBJECT_TYPE_SPECIAL
+
+typedef struct {
+
+	unsigned validMarker0;
+	unsigned chunkUsed;	/*  Status of the chunk: used or unused */
+	unsigned objectId;	/* If 0 then this is not part of an object (unused) */
+	unsigned chunkId;	/* If 0 then this is a header, else a data chunk */
+	unsigned byteCount;	/* Only valid for data chunks */
+
+	/* The following stuff only has meaning when we read */
+	yaffs_ECCResult eccResult;
+	unsigned blockBad;
+
+	/* YAFFS 1 stuff */
+	unsigned chunkDeleted;	/* The chunk is marked deleted */
+	unsigned serialNumber;	/* Yaffs1 2-bit serial number */
+
+	/* YAFFS2 stuff */
+	unsigned sequenceNumber;	/* The sequence number of this block */
+
+	/* Extra info if this is an object header (YAFFS2 only) */
+
+	unsigned extraHeaderInfoAvailable;	/* There is extra info available if this is not zero */
+	unsigned extraParentObjectId;	/* The parent object */
+	unsigned extraIsShrinkHeader;	/* Is it a shrink header? */
+	unsigned extraShadows;		/* Does this shadow another object? */
+
+	yaffs_ObjectType extraObjectType;	/* What object type? */
+
+	unsigned extraFileLength;		/* Length if it is a file */
+	unsigned extraEquivalentObjectId;	/* Equivalent object Id if it is a hard link */
+
+	unsigned validMarker1;
+
+} yaffs_ExtendedTags;
+
+/* Spare structure for YAFFS1 */
+typedef struct {
+	__u8 tagByte0;
+	__u8 tagByte1;
+	__u8 tagByte2;
+	__u8 tagByte3;
+	__u8 pageStatus;	/* set to 0 to delete the chunk */
+	__u8 blockStatus;
+	__u8 tagByte4;
+	__u8 tagByte5;
+	__u8 ecc1[3];
+	__u8 tagByte6;
+	__u8 tagByte7;
+	__u8 ecc2[3];
+} yaffs_Spare;
+
+/*Special structure for passing through to mtd */
+struct yaffs_NANDSpare {
+	yaffs_Spare spare;
+	int eccres1;
+	int eccres2;
+};
+
+/* Block data in RAM */
+
+typedef enum {
+	YAFFS_BLOCK_STATE_UNKNOWN = 0,
+
+	YAFFS_BLOCK_STATE_SCANNING,
+        /* Being scanned */
+
+	YAFFS_BLOCK_STATE_NEEDS_SCANNING,
+	/* The block might have something on it (ie it is allocating or full, perhaps empty)
+	 * but it needs to be scanned to determine its true state.
+	 * This state is only valid during yaffs_Scan.
+	 * NB We tolerate empty because the pre-scanner might be incapable of deciding
+	 * However, if this state is returned on a YAFFS2 device, then we expect a sequence number
+	 */
+
+	YAFFS_BLOCK_STATE_EMPTY,
+	/* This block is empty */
+
+	YAFFS_BLOCK_STATE_ALLOCATING,
+	/* This block is partially allocated.
+	 * At least one page holds valid data.
+	 * This is the one currently being used for page
+	 * allocation. Should never be more than one of these.
+         * If a block is only partially allocated at mount it is treated as full.
+	 */
+
+	YAFFS_BLOCK_STATE_FULL,
+	/* All the pages in this block have been allocated.
+         * If a block was only partially allocated when mounted we treat
+         * it as fully allocated.
+	 */
+
+	YAFFS_BLOCK_STATE_DIRTY,
+	/* The block was full and now all chunks have been deleted.
+	 * Erase me, reuse me.
+	 */
+
+	YAFFS_BLOCK_STATE_CHECKPOINT,
+	/* This block is assigned to holding checkpoint data. */
+
+	YAFFS_BLOCK_STATE_COLLECTING,
+	/* This block is being garbage collected */
+
+	YAFFS_BLOCK_STATE_DEAD
+	/* This block has failed and is not in use */
+} yaffs_BlockState;
+
+#define	YAFFS_NUMBER_OF_BLOCK_STATES (YAFFS_BLOCK_STATE_DEAD + 1)
+
+
+typedef struct {
+
+	int softDeletions:10;	/* number of soft deleted pages */
+	int pagesInUse:10;	/* number of pages in use */
+	unsigned blockState:4;	/* One of the above block states. NB use unsigned because enum is sometimes an int */
+	__u32 needsRetiring:1;	/* Data has failed on this block, need to get valid data off */
+				/* and retire the block. */
+	__u32 skipErasedCheck:1; /* If this is set we can skip the erased check on this block */
+	__u32 gcPrioritise:1; 	/* An ECC check or blank check has failed on this block.
+				   It should be prioritised for GC */
+	__u32 chunkErrorStrikes:3; /* How many times we've had ecc etc failures on this block and tried to reuse it */
+
+#ifdef CONFIG_YAFFS_YAFFS2
+	__u32 hasShrinkHeader:1; /* This block has at least one shrink object header */
+	__u32 sequenceNumber;	 /* block sequence number for yaffs2 */
+#endif
+
+} yaffs_BlockInfo;
+
+/* -------------------------- Object structure -------------------------------*/
+/* This is the object structure as stored on NAND */
+
+typedef struct {
+	yaffs_ObjectType type;
+
+	/* Apply to everything  */
+	int parentObjectId;
+	__u16 sum__NoLongerUsed;        /* checksum of name. No longer used */
+	YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
+
+	/* The following apply to directories, files, symlinks - not hard links */
+	__u32 yst_mode;         /* protection */
+
+#ifdef CONFIG_YAFFS_WINCE
+	__u32 notForWinCE[5];
+#else
+	__u32 yst_uid;
+	__u32 yst_gid;
+	__u32 yst_atime;
+	__u32 yst_mtime;
+	__u32 yst_ctime;
+#endif
+
+	/* File size  applies to files only */
+	int fileSize;
+
+	/* Equivalent object id applies to hard links only. */
+	int equivalentObjectId;
+
+	/* Alias is for symlinks only. */
+	YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
+
+	__u32 yst_rdev;		/* device stuff for block and char devices (major/min) */
+
+#ifdef CONFIG_YAFFS_WINCE
+	__u32 win_ctime[2];
+	__u32 win_atime[2];
+	__u32 win_mtime[2];
+#else
+	__u32 roomToGrow[6];
+
+#endif
+	__u32 inbandShadowsObject;
+	__u32 inbandIsShrink;
+
+	__u32 reservedSpace[2];
+	int shadowsObject;	/* This object header shadows the specified object if > 0 */
+
+	/* isShrink applies to object headers written when we shrink the file (ie resize) */
+	__u32 isShrink;
+
+} yaffs_ObjectHeader;
+
+/*--------------------------- Tnode -------------------------- */
+
+union yaffs_Tnode_union {
+#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
+	union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL + 1];
+#else
+	union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL];
+#endif
+/*	__u16 level0[YAFFS_NTNODES_LEVEL0]; */
+
+};
+
+typedef union yaffs_Tnode_union yaffs_Tnode;
+
+struct yaffs_TnodeList_struct {
+	struct yaffs_TnodeList_struct *next;
+	yaffs_Tnode *tnodes;
+};
+
+typedef struct yaffs_TnodeList_struct yaffs_TnodeList;
+
+/*------------------------  Object -----------------------------*/
+/* An object can be one of:
+ * - a directory (no data, has children links
+ * - a regular file (data.... not prunes :->).
+ * - a symlink [symbolic link] (the alias).
+ * - a hard link
+ */
+
+typedef struct {
+	__u32 fileSize;
+	__u32 scannedFileSize;
+	__u32 shrinkSize;
+	int topLevel;
+	yaffs_Tnode *top;
+} yaffs_FileStructure;
+
+typedef struct {
+	struct ylist_head children;     /* list of child links */
+	struct ylist_head dirty;	/* Entry for list of dirty directories */
+} yaffs_DirectoryStructure;
+
+typedef struct {
+	YCHAR *alias;
+} yaffs_SymLinkStructure;
+
+typedef struct {
+	struct yaffs_ObjectStruct *equivalentObject;
+	__u32 equivalentObjectId;
+} yaffs_HardLinkStructure;
+
+typedef union {
+	yaffs_FileStructure fileVariant;
+	yaffs_DirectoryStructure directoryVariant;
+	yaffs_SymLinkStructure symLinkVariant;
+	yaffs_HardLinkStructure hardLinkVariant;
+} yaffs_ObjectVariant;
+
+
+
+struct yaffs_ObjectStruct {
+	__u8 deleted:1;		/* This should only apply to unlinked files. */
+	__u8 softDeleted:1;	/* it has also been soft deleted */
+	__u8 unlinked:1;	/* An unlinked file. The file should be in the unlinked directory.*/
+	__u8 fake:1;		/* A fake object has no presence on NAND. */
+	__u8 renameAllowed:1;	/* Some objects are not allowed to be renamed. */
+	__u8 unlinkAllowed:1;
+	__u8 dirty:1;		/* the object needs to be written to flash */
+	__u8 valid:1;		/* When the file system is being loaded up, this
+				 * object might be created before the data
+				 * is available (ie. file data records appear before the header).
+				 */
+	__u8 lazyLoaded:1;	/* This object has been lazy loaded and is missing some detail */
+
+	__u8 deferedFree:1;	/* For Linux kernel. Object is removed from NAND, but is
+				 * still in the inode cache. Free of object is defered.
+				 * until the inode is released.
+				 */
+	__u8 beingCreated:1;	/* This object is still being created so skip some checks. */
+	__u8 isShadowed:1;	/* This object is shadowed on the way to being renamed. */
+
+	__u8 serial;		/* serial number of chunk in NAND. Cached here */
+	__u16 sum;		/* sum of the name to speed searching */
+
+	struct yaffs_DeviceStruct *myDev;       /* The device I'm on */
+
+	struct ylist_head hashLink;     /* list of objects in this hash bucket */
+
+	struct ylist_head hardLinks;    /* all the equivalent hard linked objects */
+
+	/* directory structure stuff */
+	/* also used for linking up the free list */
+	struct yaffs_ObjectStruct *parent;
+	struct ylist_head siblings;
+
+	/* Where's my object header in NAND? */
+	int hdrChunk;
+
+	int nDataChunks;	/* Number of data chunks attached to the file. */
+
+	__u32 objectId;		/* the object id value */
+
+	__u32 yst_mode;
+
+#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
+	YCHAR shortName[YAFFS_SHORT_NAME_LENGTH + 1];
+#endif
+
+#ifdef CONFIG_YAFFS_WINCE
+	__u32 win_ctime[2];
+	__u32 win_mtime[2];
+	__u32 win_atime[2];
+#else
+	__u32 yst_uid;
+	__u32 yst_gid;
+	__u32 yst_atime;
+	__u32 yst_mtime;
+	__u32 yst_ctime;
+#endif
+
+	__u32 yst_rdev;
+
+	void *myInode;
+
+	yaffs_ObjectType variantType;
+
+	yaffs_ObjectVariant variant;
+
+};
+
+typedef struct yaffs_ObjectStruct yaffs_Object;
+
+struct yaffs_ObjectList_struct {
+	yaffs_Object *objects;
+	struct yaffs_ObjectList_struct *next;
+};
+
+typedef struct yaffs_ObjectList_struct yaffs_ObjectList;
+
+typedef struct {
+	struct ylist_head list;
+	int count;
+} yaffs_ObjectBucket;
+
+
+/* yaffs_CheckpointObject holds the definition of an object as dumped
+ * by checkpointing.
+ */
+
+typedef struct {
+	int structType;
+	__u32 objectId;
+	__u32 parentId;
+	int hdrChunk;
+	yaffs_ObjectType variantType:3;
+	__u8 deleted:1;
+	__u8 softDeleted:1;
+	__u8 unlinked:1;
+	__u8 fake:1;
+	__u8 renameAllowed:1;
+	__u8 unlinkAllowed:1;
+	__u8 serial;
+
+	int nDataChunks;
+	__u32 fileSizeOrEquivalentObjectId;
+} yaffs_CheckpointObject;
+
+/*--------------------- Temporary buffers ----------------
+ *
+ * These are chunk-sized working buffers. Each device has a few
+ */
+
+typedef struct {
+	__u8 *buffer;
+	int line;	/* track from whence this buffer was allocated */
+	int maxLine;
+} yaffs_TempBuffer;
+
+/*----------------- Device ---------------------------------*/
+
+
+struct yaffs_DeviceParamStruct {
+	const char *name;
+
+	/*
+         * Entry parameters set up way early. Yaffs sets up the rest.
+         * The structure should be zeroed out before use so that unused
+         * and defualt values are zero.
+         */
+
+	int inbandTags;          /* Use unband tags */
+	__u32 totalBytesPerChunk; /* Should be >= 512, does not need to be a power of 2 */
+	int nChunksPerBlock;	/* does not need to be a power of 2 */
+	int spareBytesPerChunk;	/* spare area size */
+	int startBlock;		/* Start block we're allowed to use */
+	int endBlock;		/* End block we're allowed to use */
+	int nReservedBlocks;	/* We want this tuneable so that we can reduce */
+				/* reserved blocks on NOR and RAM. */
+
+
+	int nShortOpCaches;	/* If <= 0, then short op caching is disabled, else
+				 * the number of short op caches (don't use too many).
+                                 * 10 to 20 is a good bet.
+				 */
+	int useNANDECC;		/* Flag to decide whether or not to use NANDECC on data (yaffs1) */
+	int noTagsECC;		/* Flag to decide whether or not to do ECC on packed tags (yaffs2) */ 
+
+	int isYaffs2;           /* Use yaffs2 mode on this device */
+
+	int emptyLostAndFound;  /* Auto-empty lost+found directory on mount */
+
+	int refreshPeriod;	/* How often we should check to do a block refresh */
+
+	/* Checkpoint control. Can be set before or after initialisation */
+	__u8 skipCheckpointRead;
+	__u8 skipCheckpointWrite;
+
+	/* NAND access functions (Must be set before calling YAFFS)*/
+
+	int (*writeChunkToNAND) (struct yaffs_DeviceStruct *dev,
+					int chunkInNAND, const __u8 *data,
+					const yaffs_Spare *spare);
+	int (*readChunkFromNAND) (struct yaffs_DeviceStruct *dev,
+					int chunkInNAND, __u8 *data,
+					yaffs_Spare *spare);
+	int (*eraseBlockInNAND) (struct yaffs_DeviceStruct *dev,
+					int blockInNAND);
+	int (*initialiseNAND) (struct yaffs_DeviceStruct *dev);
+	int (*deinitialiseNAND) (struct yaffs_DeviceStruct *dev);
+
+#ifdef CONFIG_YAFFS_YAFFS2
+	int (*writeChunkWithTagsToNAND) (struct yaffs_DeviceStruct *dev,
+					 int chunkInNAND, const __u8 *data,
+					 const yaffs_ExtendedTags *tags);
+	int (*readChunkWithTagsFromNAND) (struct yaffs_DeviceStruct *dev,
+					  int chunkInNAND, __u8 *data,
+					  yaffs_ExtendedTags *tags);
+	int (*markNANDBlockBad) (struct yaffs_DeviceStruct *dev, int blockNo);
+	int (*queryNANDBlock) (struct yaffs_DeviceStruct *dev, int blockNo,
+			       yaffs_BlockState *state, __u32 *sequenceNumber);
+#endif
+
+	/* The removeObjectCallback function must be supplied by OS flavours that
+	 * need it.
+         * yaffs direct uses it to implement the faster readdir.
+         * Linux uses it to protect the directory during unlocking.
+	 */
+	void (*removeObjectCallback)(struct yaffs_ObjectStruct *obj);
+
+	/* Callback to mark the superblock dirty */
+	void (*markSuperBlockDirty)(struct yaffs_DeviceStruct *dev);
+	
+	/*  Callback to control garbage collection. */
+	unsigned (*gcControl)(struct yaffs_DeviceStruct *dev);
+
+        /* Debug control flags. Don't use unless you know what you're doing */
+	int useHeaderFileSize;	/* Flag to determine if we should use file sizes from the header */
+	int disableLazyLoad;	/* Disable lazy loading on this device */
+	int wideTnodesDisabled; /* Set to disable wide tnodes */
+	int disableSoftDelete;  /* yaffs 1 only: Set to disable the use of softdeletion. */
+	
+	int deferDirectoryUpdate; /* Set to defer directory updates */
+	
+};
+
+typedef struct yaffs_DeviceParamStruct yaffs_DeviceParam;
+
+struct yaffs_DeviceStruct {
+	struct yaffs_DeviceParamStruct param;
+
+        /* Context storage. Holds extra OS specific data for this device */
+
+	void *context;
+
+	/* Runtime parameters. Set up by YAFFS. */
+	int nDataBytesPerChunk;	
+
+        /* Non-wide tnode stuff */
+	__u16 chunkGroupBits;	/* Number of bits that need to be resolved if
+                                 * the tnodes are not wide enough.
+                                 */
+	__u16 chunkGroupSize;	/* == 2^^chunkGroupBits */
+
+	/* Stuff to support wide tnodes */
+	__u32 tnodeWidth;
+	__u32 tnodeMask;
+
+	/* Stuff for figuring out file offset to chunk conversions */
+	__u32 chunkShift; /* Shift value */
+	__u32 chunkDiv;   /* Divisor after shifting: 1 for power-of-2 sizes */
+	__u32 chunkMask;  /* Mask to use for power-of-2 case */
+
+
+
+	int isMounted;
+	int readOnly;
+	int isCheckpointed;
+
+
+	/* Stuff to support block offsetting to support start block zero */
+	int internalStartBlock;
+	int internalEndBlock;
+	int blockOffset;
+	int chunkOffset;
+
+
+	/* Runtime checkpointing stuff */
+	int checkpointPageSequence;   /* running sequence number of checkpoint pages */
+	int checkpointByteCount;
+	int checkpointByteOffset;
+	__u8 *checkpointBuffer;
+	int checkpointOpenForWrite;
+	int blocksInCheckpoint;
+	int checkpointCurrentChunk;
+	int checkpointCurrentBlock;
+	int checkpointNextBlock;
+	int *checkpointBlockList;
+	int checkpointMaxBlocks;
+	__u32 checkpointSum;
+	__u32 checkpointXor;
+
+	int nCheckpointBlocksRequired; /* Number of blocks needed to store current checkpoint set */
+
+	/* Block Info */
+	yaffs_BlockInfo *blockInfo;
+	__u8 *chunkBits;	/* bitmap of chunks in use */
+	unsigned blockInfoAlt:1;	/* was allocated using alternative strategy */
+	unsigned chunkBitsAlt:1;	/* was allocated using alternative strategy */
+	int chunkBitmapStride;	/* Number of bytes of chunkBits per block.
+				 * Must be consistent with nChunksPerBlock.
+				 */
+
+	int nErasedBlocks;
+	int allocationBlock;	/* Current block being allocated off */
+	__u32 allocationPage;
+	int allocationBlockFinder;	/* Used to search for next allocation block */
+
+	int nTnodesCreated;
+	yaffs_Tnode *freeTnodes;
+	int nFreeTnodes;
+	yaffs_TnodeList *allocatedTnodeList;
+
+	int nObjectsCreated;
+	yaffs_Object *freeObjects;
+	int nFreeObjects;
+
+	int nHardLinks;
+
+	yaffs_ObjectList *allocatedObjectList;
+
+	yaffs_ObjectBucket objectBucket[YAFFS_NOBJECT_BUCKETS];
+	__u32 bucketFinder;
+
+	int nFreeChunks;
+
+	/* Garbage collection control */
+	__u32 *gcCleanupList;	/* objects to delete at the end of a GC. */
+
+	unsigned hasPendingPrioritisedGCs; /* We think this device might have pending prioritised gcs */
+	unsigned gcDisable;
+	unsigned gcBlockFinder;
+	unsigned gcDirtiest;
+	unsigned gcPagesInUse;
+	unsigned gcNotDone;
+	unsigned gcBlock;
+	unsigned gcChunk;
+	unsigned gcSkip;
+
+	/* Special directories */
+	yaffs_Object *rootDir;
+	yaffs_Object *lostNFoundDir;
+
+	/* Buffer areas for storing data to recover from write failures TODO
+	 *      __u8            bufferedData[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
+	 *      yaffs_Spare bufferedSpare[YAFFS_CHUNKS_PER_BLOCK];
+	 */
+
+	int bufferedBlock;	/* Which block is buffered here? */
+	int doingBufferedBlockRewrite;
+
+	yaffs_ChunkCache *srCache;
+	int srLastUse;
+
+	/* Stuff for background deletion and unlinked files.*/
+	yaffs_Object *unlinkedDir;	/* Directory where unlinked and deleted files live. */
+	yaffs_Object *deletedDir;	/* Directory where deleted objects are sent to disappear. */
+	yaffs_Object *unlinkedDeletion;	/* Current file being background deleted.*/
+	int nDeletedFiles;		/* Count of files awaiting deletion;*/
+	int nUnlinkedFiles;		/* Count of unlinked files. */
+	int nBackgroundDeletions;	/* Count of background deletions. */
+
+	/* Temporary buffer management */
+	yaffs_TempBuffer tempBuffer[YAFFS_N_TEMP_BUFFERS];
+	int maxTemp;
+	int tempInUse;
+	int unmanagedTempAllocations;
+	int unmanagedTempDeallocations;
+
+	/* yaffs2 runtime stuff */
+	unsigned sequenceNumber;	/* Sequence number of currently allocating block */
+	unsigned oldestDirtySequence;
+	unsigned oldestDirtyBlock;
+
+	/* Block refreshing */
+	int refreshSkip;	/* A skip down counter. Refresh happens when this gets to zero. */
+
+	/* Dirty directory handling */
+	struct ylist_head dirtyDirectories; /* List of dirty directories */
+
+
+	/* Statistcs */
+	__u32 nPageWrites;
+	__u32 nPageReads;
+	__u32 nBlockErasures;
+	__u32 nErasureFailures;
+	__u32 nGCCopies;
+	__u32 allGCs;
+	__u32 passiveGCs;
+	__u32 oldestDirtyGCs;
+	__u32 backgroundGCs;
+	__u32 nRetriedWrites;
+	__u32 nRetiredBlocks;
+	__u32 eccFixed;
+	__u32 eccUnfixed;
+	__u32 tagsEccFixed;
+	__u32 tagsEccUnfixed;
+	__u32 nDeletions;
+	__u32 nUnmarkedDeletions;
+	__u32 refreshCount;
+	__u32 cacheHits;
+
+};
+
+typedef struct yaffs_DeviceStruct yaffs_Device;
+
+/* The static layout of block usage etc is stored in the super block header */
+typedef struct {
+	int StructType;
+	int version;
+	int checkpointStartBlock;
+	int checkpointEndBlock;
+	int startBlock;
+	int endBlock;
+	int rfu[100];
+} yaffs_SuperBlockHeader;
+
+/* The CheckpointDevice structure holds the device information that changes at runtime and
+ * must be preserved over unmount/mount cycles.
+ */
+typedef struct {
+	int structType;
+	int nErasedBlocks;
+	int allocationBlock;	/* Current block being allocated off */
+	__u32 allocationPage;
+	int nFreeChunks;
+
+	int nDeletedFiles;		/* Count of files awaiting deletion;*/
+	int nUnlinkedFiles;		/* Count of unlinked files. */
+	int nBackgroundDeletions;	/* Count of background deletions. */
+
+	/* yaffs2 runtime stuff */
+	unsigned sequenceNumber;	/* Sequence number of currently allocating block */
+
+} yaffs_CheckpointDevice;
+
+
+typedef struct {
+	int structType;
+	__u32 magic;
+	__u32 version;
+	__u32 head;
+} yaffs_CheckpointValidity;
+
+
+/*----------------------- YAFFS Functions -----------------------*/
+
+int yaffs_GutsInitialise(yaffs_Device *dev);
+void yaffs_Deinitialise(yaffs_Device *dev);
+
+int yaffs_GetNumberOfFreeChunks(yaffs_Device *dev);
+
+int yaffs_RenameObject(yaffs_Object *oldDir, const YCHAR *oldName,
+		       yaffs_Object *newDir, const YCHAR *newName);
+
+int yaffs_Unlink(yaffs_Object *dir, const YCHAR *name);
+int yaffs_DeleteObject(yaffs_Object *obj);
+
+int yaffs_GetObjectName(yaffs_Object *obj, YCHAR *name, int buffSize);
+int yaffs_GetObjectFileLength(yaffs_Object *obj);
+int yaffs_GetObjectInode(yaffs_Object *obj);
+unsigned yaffs_GetObjectType(yaffs_Object *obj);
+int yaffs_GetObjectLinkCount(yaffs_Object *obj);
+
+int yaffs_SetAttributes(yaffs_Object *obj, struct iattr *attr);
+int yaffs_GetAttributes(yaffs_Object *obj, struct iattr *attr);
+
+/* File operations */
+int yaffs_ReadDataFromFile(yaffs_Object *obj, __u8 *buffer, loff_t offset,
+				int nBytes);
+int yaffs_WriteDataToFile(yaffs_Object *obj, const __u8 *buffer, loff_t offset,
+				int nBytes, int writeThrough);
+int yaffs_ResizeFile(yaffs_Object *obj, loff_t newSize);
+
+yaffs_Object *yaffs_MknodFile(yaffs_Object *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid);
+
+int yaffs_FlushFile(yaffs_Object *obj, int updateTime, int dataSync);
+
+/* Flushing and checkpointing */
+void yaffs_FlushEntireDeviceCache(yaffs_Device *dev);
+
+int yaffs_CheckpointSave(yaffs_Device *dev);
+int yaffs_CheckpointRestore(yaffs_Device *dev);
+
+/* Directory operations */
+yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent, const YCHAR *name,
+				__u32 mode, __u32 uid, __u32 gid);
+yaffs_Object *yaffs_FindObjectByName(yaffs_Object *theDir, const YCHAR *name);
+int yaffs_ApplyToDirectoryChildren(yaffs_Object *theDir,
+				   int (*fn) (yaffs_Object *));
+
+yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev, __u32 number);
+
+/* Link operations */
+yaffs_Object *yaffs_Link(yaffs_Object *parent, const YCHAR *name,
+			 yaffs_Object *equivalentObject);
+
+yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj);
+
+/* Symlink operations */
+yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent, const YCHAR *name,
+				 __u32 mode, __u32 uid, __u32 gid,
+				 const YCHAR *alias);
+YCHAR *yaffs_GetSymlinkAlias(yaffs_Object *obj);
+
+/* Special inodes (fifos, sockets and devices) */
+yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent, const YCHAR *name,
+				 __u32 mode, __u32 uid, __u32 gid, __u32 rdev);
+
+/* Special directories */
+yaffs_Object *yaffs_Root(yaffs_Device *dev);
+yaffs_Object *yaffs_LostNFound(yaffs_Device *dev);
+
+#ifdef CONFIG_YAFFS_WINCE
+/* CONFIG_YAFFS_WINCE special stuff */
+void yfsd_WinFileTimeNow(__u32 target[2]);
+#endif
+
+void yaffs_HandleDeferedFree(yaffs_Object *obj);
+
+void yaffs_UpdateDirtyDirectories(yaffs_Device *dev);
+
+int yaffs_BackgroundGarbageCollect(yaffs_Device *dev, unsigned urgency);
+
+/* Debug dump  */
+int yaffs_DumpObject(yaffs_Object *obj);
+
+void yaffs_GutsTest(yaffs_Device *dev);
+
+/* A few useful functions */
+void yaffs_InitialiseTags(yaffs_ExtendedTags *tags);
+void yaffs_DeleteChunk(yaffs_Device *dev, int chunkId, int markNAND, int lyn);
+int yaffs_CheckFF(__u8 *buffer, int nBytes);
+void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi);
+
+__u8 *yaffs_GetTempBuffer(yaffs_Device *dev, int lineNo);
+void yaffs_ReleaseTempBuffer(yaffs_Device *dev, __u8 *buffer, int lineNo);
+
+
+#endif
diff --git a/fs/yaffs2/yaffs_linux.h b/fs/yaffs2/yaffs_linux.h
new file mode 100644
index 00000000000..4434e6c497b
--- /dev/null
+++ b/fs/yaffs2/yaffs_linux.h
@@ -0,0 +1,42 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_LINUX_H__
+#define __YAFFS_LINUX_H__
+
+#include "devextras.h"
+#include "yportenv.h"
+
+struct yaffs_LinuxContext {
+	struct ylist_head	contextList; /* List of these we have mounted */
+	struct yaffs_DeviceStruct *dev;
+	struct super_block * superBlock;
+	struct task_struct *bgThread; /* Background thread for this device */
+	int bgRunning;
+        struct semaphore grossLock;     /* Gross locking semaphore */
+	__u8 *spareBuffer;      /* For mtdif2 use. Don't know the size of the buffer
+				 * at compile time so we have to allocate it.
+				 */
+	struct mtd_info *mtd;
+	struct ylist_head searchContexts;
+	void (*putSuperFunc)(struct super_block *sb);
+
+	struct task_struct *readdirProcess;
+};
+
+#define yaffs_DeviceToContext(dev) ((struct yaffs_LinuxContext *)((dev)->context))
+
+#endif
+
diff --git a/fs/yaffs2/yaffs_mtdif.c b/fs/yaffs2/yaffs_mtdif.c
new file mode 100644
index 00000000000..5de3193ea2b
--- /dev/null
+++ b/fs/yaffs2/yaffs_mtdif.c
@@ -0,0 +1,56 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yportenv.h"
+
+
+#include "yaffs_mtdif.h"
+
+#include "linux/mtd/mtd.h"
+#include "linux/types.h"
+#include "linux/time.h"
+#include "linux/mtd/nand.h"
+
+#include "yaffs_linux.h"
+
+int nandmtd_EraseBlockInNAND(yaffs_Device *dev, int blockNumber)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+	__u32 addr =
+	    ((loff_t) blockNumber) * dev->param.totalBytesPerChunk
+		* dev->param.nChunksPerBlock;
+	struct erase_info ei;
+	
+	int retval = 0;
+
+	ei.mtd = mtd;
+	ei.addr = addr;
+	ei.len = dev->param.totalBytesPerChunk * dev->param.nChunksPerBlock;
+	ei.time = 1000;
+	ei.retries = 2;
+	ei.callback = NULL;
+	ei.priv = (u_long) dev;
+
+	retval = mtd->erase(mtd, &ei);
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
+int nandmtd_InitialiseNAND(yaffs_Device *dev)
+{
+	return YAFFS_OK;
+}
+
diff --git a/fs/yaffs2/yaffs_mtdif.h b/fs/yaffs2/yaffs_mtdif.h
new file mode 100644
index 00000000000..fad9d287061
--- /dev/null
+++ b/fs/yaffs2/yaffs_mtdif.h
@@ -0,0 +1,27 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_MTDIF_H__
+#define __YAFFS_MTDIF_H__
+
+#include "yaffs_guts.h"
+
+#if (MTD_VERSION_CODE < MTD_VERSION(2, 6, 18))
+extern struct nand_oobinfo yaffs_oobinfo;
+extern struct nand_oobinfo yaffs_noeccinfo;
+#endif
+int nandmtd_EraseBlockInNAND(yaffs_Device *dev, int blockNumber);
+int nandmtd_InitialiseNAND(yaffs_Device *dev);
+#endif
diff --git a/fs/yaffs2/yaffs_mtdif1.c b/fs/yaffs2/yaffs_mtdif1.c
new file mode 100644
index 00000000000..aaa02db2f66
--- /dev/null
+++ b/fs/yaffs2/yaffs_mtdif1.c
@@ -0,0 +1,361 @@
+/*
+ * YAFFS: Yet another FFS. A NAND-flash specific file system.
+ * yaffs_mtdif1.c  NAND mtd interface functions for small-page NAND.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This module provides the interface between yaffs_nand.c and the
+ * MTD API.  This version is used when the MTD interface supports the
+ * 'mtd_oob_ops' style calls to read_oob and write_oob, circa 2.6.17,
+ * and we have small-page NAND device.
+ *
+ * These functions are invoked via function pointers in yaffs_nand.c.
+ * This replaces functionality provided by functions in yaffs_mtdif.c
+ * and the yaffs_TagsCompatability functions in yaffs_tagscompat.c that are
+ * called in yaffs_mtdif.c when the function pointers are NULL.
+ * We assume the MTD layer is performing ECC (useNANDECC is true).
+ */
+
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_guts.h"
+#include "yaffs_packedtags1.h"
+#include "yaffs_tagscompat.h"	/* for yaffs_CalcTagsECC */
+#include "yaffs_linux.h"
+
+#include "linux/kernel.h"
+#include "linux/version.h"
+#include "linux/types.h"
+#include "linux/mtd/mtd.h"
+
+/* Don't compile this module if we don't have MTD's mtd_oob_ops interface */
+#if (MTD_VERSION_CODE > MTD_VERSION(2, 6, 17))
+
+#ifndef CONFIG_YAFFS_9BYTE_TAGS
+# define YTAG1_SIZE 8
+#else
+# define YTAG1_SIZE 9
+#endif
+
+#if 0
+/* Use the following nand_ecclayout with MTD when using
+ * CONFIG_YAFFS_9BYTE_TAGS and the older on-NAND tags layout.
+ * If you have existing Yaffs images and the byte order differs from this,
+ * adjust 'oobfree' to match your existing Yaffs data.
+ *
+ * This nand_ecclayout scatters/gathers to/from the old-yaffs layout with the
+ * pageStatus byte (at NAND spare offset 4) scattered/gathered from/to
+ * the 9th byte.
+ *
+ * Old-style on-NAND format: T0,T1,T2,T3,P,B,T4,T5,E0,E1,E2,T6,T7,E3,E4,E5
+ * We have/need PackedTags1 plus pageStatus: T0,T1,T2,T3,T4,T5,T6,T7,P
+ * where Tn are the tag bytes, En are MTD's ECC bytes, P is the pageStatus
+ * byte and B is the small-page bad-block indicator byte.
+ */
+static struct nand_ecclayout nand_oob_16 = {
+	.eccbytes = 6,
+	.eccpos = { 8, 9, 10, 13, 14, 15 },
+	.oobavail = 9,
+	.oobfree = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
+};
+#endif
+
+/* Write a chunk (page) of data to NAND.
+ *
+ * Caller always provides ExtendedTags data which are converted to a more
+ * compact (packed) form for storage in NAND.  A mini-ECC runs over the
+ * contents of the tags meta-data; used to valid the tags when read.
+ *
+ *  - Pack ExtendedTags to PackedTags1 form
+ *  - Compute mini-ECC for PackedTags1
+ *  - Write data and packed tags to NAND.
+ *
+ * Note: Due to the use of the PackedTags1 meta-data which does not include
+ * a full sequence number (as found in the larger PackedTags2 form) it is
+ * necessary for Yaffs to re-write a chunk/page (just once) to mark it as
+ * discarded and dirty.  This is not ideal: newer NAND parts are supposed
+ * to be written just once.  When Yaffs performs this operation, this
+ * function is called with a NULL data pointer -- calling MTD write_oob
+ * without data is valid usage (2.6.17).
+ *
+ * Any underlying MTD error results in YAFFS_FAIL.
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+int nandmtd1_WriteChunkWithTagsToNAND(yaffs_Device *dev,
+	int chunkInNAND, const __u8 *data, const yaffs_ExtendedTags *etags)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+	int chunkBytes = dev->nDataBytesPerChunk;
+	loff_t addr = ((loff_t)chunkInNAND) * chunkBytes;
+	struct mtd_oob_ops ops;
+	yaffs_PackedTags1 pt1;
+	int retval;
+
+	/* we assume that PackedTags1 and yaffs_Tags are compatible */
+	compile_time_assertion(sizeof(yaffs_PackedTags1) == 12);
+	compile_time_assertion(sizeof(yaffs_Tags) == 8);
+
+	yaffs_PackTags1(&pt1, etags);
+	yaffs_CalcTagsECC((yaffs_Tags *)&pt1);
+
+	/* When deleting a chunk, the upper layer provides only skeletal
+	 * etags, one with chunkDeleted set.  However, we need to update the
+	 * tags, not erase them completely.  So we use the NAND write property
+	 * that only zeroed-bits stick and set tag bytes to all-ones and
+	 * zero just the (not) deleted bit.
+	 */
+#ifndef CONFIG_YAFFS_9BYTE_TAGS
+	if (etags->chunkDeleted) {
+		memset(&pt1, 0xff, 8);
+		/* clear delete status bit to indicate deleted */
+		pt1.deleted = 0;
+	}
+#else
+	((__u8 *)&pt1)[8] = 0xff;
+	if (etags->chunkDeleted) {
+		memset(&pt1, 0xff, 8);
+		/* zero pageStatus byte to indicate deleted */
+		((__u8 *)&pt1)[8] = 0;
+	}
+#endif
+
+	memset(&ops, 0, sizeof(ops));
+	ops.mode = MTD_OOB_AUTO;
+	ops.len = (data) ? chunkBytes : 0;
+	ops.ooblen = YTAG1_SIZE;
+	ops.datbuf = (__u8 *)data;
+	ops.oobbuf = (__u8 *)&pt1;
+
+	retval = mtd->write_oob(mtd, addr, &ops);
+	if (retval) {
+		T(YAFFS_TRACE_MTD,
+			(TSTR("write_oob failed, chunk %d, mtd error %d"TENDSTR),
+			chunkInNAND, retval));
+	}
+	return retval ? YAFFS_FAIL : YAFFS_OK;
+}
+
+/* Return with empty ExtendedTags but add eccResult.
+ */
+static int rettags(yaffs_ExtendedTags *etags, int eccResult, int retval)
+{
+	if (etags) {
+		memset(etags, 0, sizeof(*etags));
+		etags->eccResult = eccResult;
+	}
+	return retval;
+}
+
+/* Read a chunk (page) from NAND.
+ *
+ * Caller expects ExtendedTags data to be usable even on error; that is,
+ * all members except eccResult and blockBad are zeroed.
+ *
+ *  - Check ECC results for data (if applicable)
+ *  - Check for blank/erased block (return empty ExtendedTags if blank)
+ *  - Check the PackedTags1 mini-ECC (correct if necessary/possible)
+ *  - Convert PackedTags1 to ExtendedTags
+ *  - Update eccResult and blockBad members to refect state.
+ *
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+int nandmtd1_ReadChunkWithTagsFromNAND(yaffs_Device *dev,
+	int chunkInNAND, __u8 *data, yaffs_ExtendedTags *etags)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+	int chunkBytes = dev->nDataBytesPerChunk;
+	loff_t addr = ((loff_t)chunkInNAND) * chunkBytes;
+	int eccres = YAFFS_ECC_RESULT_NO_ERROR;
+	struct mtd_oob_ops ops;
+	yaffs_PackedTags1 pt1;
+	int retval;
+	int deleted;
+
+	memset(&ops, 0, sizeof(ops));
+	ops.mode = MTD_OOB_AUTO;
+	ops.len = (data) ? chunkBytes : 0;
+	ops.ooblen = YTAG1_SIZE;
+	ops.datbuf = data;
+	ops.oobbuf = (__u8 *)&pt1;
+
+#if (MTD_VERSION_CODE < MTD_VERSION(2, 6, 20))
+	/* In MTD 2.6.18 to 2.6.19 nand_base.c:nand_do_read_oob() has a bug;
+	 * help it out with ops.len = ops.ooblen when ops.datbuf == NULL.
+	 */
+	ops.len = (ops.datbuf) ? ops.len : ops.ooblen;
+#endif
+	/* Read page and oob using MTD.
+	 * Check status and determine ECC result.
+	 */
+	retval = mtd->read_oob(mtd, addr, &ops);
+	if (retval) {
+		T(YAFFS_TRACE_MTD,
+			(TSTR("read_oob failed, chunk %d, mtd error %d"TENDSTR),
+			chunkInNAND, retval));
+	}
+
+	switch (retval) {
+	case 0:
+		/* no error */
+		break;
+
+	case -EUCLEAN:
+		/* MTD's ECC fixed the data */
+		eccres = YAFFS_ECC_RESULT_FIXED;
+		dev->eccFixed++;
+		break;
+
+	case -EBADMSG:
+		/* MTD's ECC could not fix the data */
+		dev->eccUnfixed++;
+		/* fall into... */
+	default:
+		rettags(etags, YAFFS_ECC_RESULT_UNFIXED, 0);
+		etags->blockBad = (mtd->block_isbad)(mtd, addr);
+		return YAFFS_FAIL;
+	}
+
+	/* Check for a blank/erased chunk.
+	 */
+	if (yaffs_CheckFF((__u8 *)&pt1, 8)) {
+		/* when blank, upper layers want eccResult to be <= NO_ERROR */
+		return rettags(etags, YAFFS_ECC_RESULT_NO_ERROR, YAFFS_OK);
+	}
+
+#ifndef CONFIG_YAFFS_9BYTE_TAGS
+	/* Read deleted status (bit) then return it to it's non-deleted
+	 * state before performing tags mini-ECC check. pt1.deleted is
+	 * inverted.
+	 */
+	deleted = !pt1.deleted;
+	pt1.deleted = 1;
+#else
+	deleted = (yaffs_CountBits(((__u8 *)&pt1)[8]) < 7);
+#endif
+
+	/* Check the packed tags mini-ECC and correct if necessary/possible.
+	 */
+	retval = yaffs_CheckECCOnTags((yaffs_Tags *)&pt1);
+	switch (retval) {
+	case 0:
+		/* no tags error, use MTD result */
+		break;
+	case 1:
+		/* recovered tags-ECC error */
+		dev->tagsEccFixed++;
+		if (eccres == YAFFS_ECC_RESULT_NO_ERROR)
+			eccres = YAFFS_ECC_RESULT_FIXED;
+		break;
+	default:
+		/* unrecovered tags-ECC error */
+		dev->tagsEccUnfixed++;
+		return rettags(etags, YAFFS_ECC_RESULT_UNFIXED, YAFFS_FAIL);
+	}
+
+	/* Unpack the tags to extended form and set ECC result.
+	 * [set shouldBeFF just to keep yaffs_UnpackTags1 happy]
+	 */
+	pt1.shouldBeFF = 0xFFFFFFFF;
+	yaffs_UnpackTags1(etags, &pt1);
+	etags->eccResult = eccres;
+
+	/* Set deleted state */
+	etags->chunkDeleted = deleted;
+	return YAFFS_OK;
+}
+
+/* Mark a block bad.
+ *
+ * This is a persistant state.
+ * Use of this function should be rare.
+ *
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+int nandmtd1_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+	int blocksize = dev->param.nChunksPerBlock * dev->nDataBytesPerChunk;
+	int retval;
+
+	T(YAFFS_TRACE_BAD_BLOCKS,(TSTR("marking block %d bad"TENDSTR), blockNo));
+
+	retval = mtd->block_markbad(mtd, (loff_t)blocksize * blockNo);
+	return (retval) ? YAFFS_FAIL : YAFFS_OK;
+}
+
+/* Check any MTD prerequists.
+ *
+ * Returns YAFFS_OK or YAFFS_FAIL.
+ */
+static int nandmtd1_TestPrerequists(struct mtd_info *mtd)
+{
+	/* 2.6.18 has mtd->ecclayout->oobavail */
+	/* 2.6.21 has mtd->ecclayout->oobavail and mtd->oobavail */
+	int oobavail = mtd->ecclayout->oobavail;
+
+	if (oobavail < YTAG1_SIZE) {
+		T(YAFFS_TRACE_ERROR,
+			(TSTR("mtd device has only %d bytes for tags, need %d"TENDSTR),
+			oobavail, YTAG1_SIZE));
+		return YAFFS_FAIL;
+	}
+	return YAFFS_OK;
+}
+
+/* Query for the current state of a specific block.
+ *
+ * Examine the tags of the first chunk of the block and return the state:
+ *  - YAFFS_BLOCK_STATE_DEAD, the block is marked bad
+ *  - YAFFS_BLOCK_STATE_NEEDS_SCANNING, the block is in use
+ *  - YAFFS_BLOCK_STATE_EMPTY, the block is clean
+ *
+ * Always returns YAFFS_OK.
+ */
+int nandmtd1_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo,
+	yaffs_BlockState *pState, __u32 *pSequenceNumber)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+	int chunkNo = blockNo * dev->param.nChunksPerBlock;
+	loff_t addr = (loff_t)chunkNo * dev->nDataBytesPerChunk;
+	yaffs_ExtendedTags etags;
+	int state = YAFFS_BLOCK_STATE_DEAD;
+	int seqnum = 0;
+	int retval;
+
+	/* We don't yet have a good place to test for MTD config prerequists.
+	 * Do it here as we are called during the initial scan.
+	 */
+	if (nandmtd1_TestPrerequists(mtd) != YAFFS_OK)
+		return YAFFS_FAIL;
+
+	retval = nandmtd1_ReadChunkWithTagsFromNAND(dev, chunkNo, NULL, &etags);
+	etags.blockBad = (mtd->block_isbad)(mtd, addr);
+	if (etags.blockBad) {
+		T(YAFFS_TRACE_BAD_BLOCKS,
+			(TSTR("block %d is marked bad"TENDSTR), blockNo));
+		state = YAFFS_BLOCK_STATE_DEAD;
+	} else if (etags.eccResult != YAFFS_ECC_RESULT_NO_ERROR) {
+		/* bad tags, need to look more closely */
+		state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+	} else if (etags.chunkUsed) {
+		state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+		seqnum = etags.sequenceNumber;
+	} else {
+		state = YAFFS_BLOCK_STATE_EMPTY;
+	}
+
+	*pState = state;
+	*pSequenceNumber = seqnum;
+
+	/* query always succeeds */
+	return YAFFS_OK;
+}
+
+#endif /*MTD_VERSION*/
diff --git a/fs/yaffs2/yaffs_mtdif1.h b/fs/yaffs2/yaffs_mtdif1.h
new file mode 100644
index 00000000000..0e6a56fbd54
--- /dev/null
+++ b/fs/yaffs2/yaffs_mtdif1.h
@@ -0,0 +1,28 @@
+/*
+ * YAFFS: Yet another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_MTDIF1_H__
+#define __YAFFS_MTDIF1_H__
+
+int nandmtd1_WriteChunkWithTagsToNAND(yaffs_Device *dev, int chunkInNAND,
+	const __u8 *data, const yaffs_ExtendedTags *tags);
+
+int nandmtd1_ReadChunkWithTagsFromNAND(yaffs_Device *dev, int chunkInNAND,
+	__u8 *data, yaffs_ExtendedTags *tags);
+
+int nandmtd1_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo);
+
+int nandmtd1_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo,
+	yaffs_BlockState *state, __u32 *sequenceNumber);
+
+#endif
diff --git a/fs/yaffs2/yaffs_mtdif2.c b/fs/yaffs2/yaffs_mtdif2.c
new file mode 100644
index 00000000000..c1d44781997
--- /dev/null
+++ b/fs/yaffs2/yaffs_mtdif2.c
@@ -0,0 +1,257 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* mtd interface for YAFFS2 */
+
+#include "yportenv.h"
+#include "yaffs_trace.h"
+
+#include "yaffs_mtdif2.h"
+
+#include "linux/mtd/mtd.h"
+#include "linux/types.h"
+#include "linux/time.h"
+
+#include "yaffs_packedtags2.h"
+
+#include "yaffs_linux.h"
+
+/* NB For use with inband tags....
+ * We assume that the data buffer is of size totalBytersPerChunk so that we can also
+ * use it to load the tags.
+ */
+int nandmtd2_WriteChunkWithTagsToNAND(yaffs_Device *dev, int chunkInNAND,
+				      const __u8 *data,
+				      const yaffs_ExtendedTags *tags)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+#if (MTD_VERSION_CODE > MTD_VERSION(2, 6, 17))
+	struct mtd_oob_ops ops;
+#else
+	size_t dummy;
+#endif
+	int retval = 0;
+
+	loff_t addr;
+
+	yaffs_PackedTags2 pt;
+
+	int packed_tags_size = dev->param.noTagsECC ? sizeof(pt.t) : sizeof(pt);
+	void * packed_tags_ptr = dev->param.noTagsECC ? (void *) &pt.t : (void *)&pt;
+
+	T(YAFFS_TRACE_MTD,
+	  (TSTR
+	   ("nandmtd2_WriteChunkWithTagsToNAND chunk %d data %p tags %p"
+	    TENDSTR), chunkInNAND, data, tags));
+
+
+	addr  = ((loff_t) chunkInNAND) * dev->param.totalBytesPerChunk;
+
+	/* For yaffs2 writing there must be both data and tags.
+	 * If we're using inband tags, then the tags are stuffed into
+	 * the end of the data buffer.
+	 */
+	if (!data || !tags)
+		BUG();
+	else if (dev->param.inbandTags) {
+		yaffs_PackedTags2TagsPart *pt2tp;
+		pt2tp = (yaffs_PackedTags2TagsPart *)(data + dev->nDataBytesPerChunk);
+		yaffs_PackTags2TagsPart(pt2tp, tags);
+	} else
+		yaffs_PackTags2(&pt, tags, !dev->param.noTagsECC);
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+	ops.mode = MTD_OOB_AUTO;
+	ops.ooblen = (dev->param.inbandTags) ? 0 : packed_tags_size;
+	ops.len = dev->param.totalBytesPerChunk;
+	ops.ooboffs = 0;
+	ops.datbuf = (__u8 *)data;
+	ops.oobbuf = (dev->param.inbandTags) ? NULL : packed_tags_ptr;
+	retval = mtd->write_oob(mtd, addr, &ops);
+
+#else
+	if (!dev->param.inbandTags) {
+		retval =
+		    mtd->write_ecc(mtd, addr, dev->nDataBytesPerChunk,
+				   &dummy, data, (__u8 *) packed_tags_ptr, NULL);
+	} else {
+		retval =
+		    mtd->write(mtd, addr, dev->param.totalBytesPerChunk, &dummy,
+			       data);
+	}
+#endif
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
+int nandmtd2_ReadChunkWithTagsFromNAND(yaffs_Device *dev, int chunkInNAND,
+				       __u8 *data, yaffs_ExtendedTags *tags)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+#if (MTD_VERSION_CODE > MTD_VERSION(2, 6, 17))
+	struct mtd_oob_ops ops;
+#endif
+	size_t dummy;
+	int retval = 0;
+	int localData = 0;
+
+	loff_t addr = ((loff_t) chunkInNAND) * dev->param.totalBytesPerChunk;
+
+	yaffs_PackedTags2 pt;
+
+	int packed_tags_size = dev->param.noTagsECC ? sizeof(pt.t) : sizeof(pt);
+	void * packed_tags_ptr = dev->param.noTagsECC ? (void *) &pt.t: (void *)&pt;
+
+	T(YAFFS_TRACE_MTD,
+	  (TSTR
+	   ("nandmtd2_ReadChunkWithTagsFromNAND chunk %d data %p tags %p"
+	    TENDSTR), chunkInNAND, data, tags));
+
+	if (dev->param.inbandTags) {
+
+		if (!data) {
+			localData = 1;
+			data = yaffs_GetTempBuffer(dev, __LINE__);
+		}
+
+
+	}
+
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 17))
+	if (dev->param.inbandTags || (data && !tags))
+		retval = mtd->read(mtd, addr, dev->param.totalBytesPerChunk,
+				&dummy, data);
+	else if (tags) {
+		ops.mode = MTD_OOB_AUTO;
+		ops.ooblen = packed_tags_size;
+		ops.len = data ? dev->nDataBytesPerChunk : packed_tags_size;
+		ops.ooboffs = 0;
+		ops.datbuf = data;
+		ops.oobbuf = yaffs_DeviceToContext(dev)->spareBuffer;
+		retval = mtd->read_oob(mtd, addr, &ops);
+	}
+#else
+	if (!dev->param.inbandTags && data && tags) {
+
+		retval = mtd->read_ecc(mtd, addr, dev->nDataBytesPerChunk,
+					  &dummy, data, dev->spareBuffer,
+					  NULL);
+	} else {
+		if (data)
+			retval =
+			    mtd->read(mtd, addr, dev->nDataBytesPerChunk, &dummy,
+				      data);
+		if (!dev->param.inbandTags && tags)
+			retval =
+			    mtd->read_oob(mtd, addr, mtd->oobsize, &dummy,
+					  dev->spareBuffer);
+	}
+#endif
+
+
+	if (dev->param.inbandTags) {
+		if (tags) {
+			yaffs_PackedTags2TagsPart *pt2tp;
+			pt2tp = (yaffs_PackedTags2TagsPart *)&data[dev->nDataBytesPerChunk];
+			yaffs_UnpackTags2TagsPart(tags, pt2tp);
+		}
+	} else {
+		if (tags) {
+			memcpy(packed_tags_ptr, yaffs_DeviceToContext(dev)->spareBuffer, packed_tags_size);
+			yaffs_UnpackTags2(tags, &pt, !dev->param.noTagsECC);
+		}
+	}
+
+	if (localData)
+		yaffs_ReleaseTempBuffer(dev, data, __LINE__);
+
+	if (tags && retval == -EBADMSG && tags->eccResult == YAFFS_ECC_RESULT_NO_ERROR) {
+		tags->eccResult = YAFFS_ECC_RESULT_UNFIXED;
+		dev->eccUnfixed++;
+	}
+	if(tags && retval == -EUCLEAN && tags->eccResult == YAFFS_ECC_RESULT_NO_ERROR) {
+		tags->eccResult = YAFFS_ECC_RESULT_FIXED;
+		dev->eccFixed++;
+	}
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
+int nandmtd2_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+	int retval;
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("nandmtd2_MarkNANDBlockBad %d" TENDSTR), blockNo));
+
+	retval =
+	    mtd->block_markbad(mtd,
+			       blockNo * dev->param.nChunksPerBlock *
+			       dev->param.totalBytesPerChunk);
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+
+}
+
+int nandmtd2_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo,
+			    yaffs_BlockState *state, __u32 *sequenceNumber)
+{
+	struct mtd_info *mtd = yaffs_DeviceToContext(dev)->mtd;
+	int retval;
+
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("nandmtd2_QueryNANDBlock %d" TENDSTR), blockNo));
+	retval =
+	    mtd->block_isbad(mtd,
+			     blockNo * dev->param.nChunksPerBlock *
+			     dev->param.totalBytesPerChunk);
+
+	if (retval) {
+		T(YAFFS_TRACE_MTD, (TSTR("block is bad" TENDSTR)));
+
+		*state = YAFFS_BLOCK_STATE_DEAD;
+		*sequenceNumber = 0;
+	} else {
+		yaffs_ExtendedTags t;
+		nandmtd2_ReadChunkWithTagsFromNAND(dev,
+						   blockNo *
+						   dev->param.nChunksPerBlock, NULL,
+						   &t);
+
+		if (t.chunkUsed) {
+			*sequenceNumber = t.sequenceNumber;
+			*state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+		} else {
+			*sequenceNumber = 0;
+			*state = YAFFS_BLOCK_STATE_EMPTY;
+		}
+	}
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("block is bad seq %d state %d" TENDSTR), *sequenceNumber,
+	   *state));
+
+	if (retval == 0)
+		return YAFFS_OK;
+	else
+		return YAFFS_FAIL;
+}
+
diff --git a/fs/yaffs2/yaffs_mtdif2.h b/fs/yaffs2/yaffs_mtdif2.h
new file mode 100644
index 00000000000..5691267eafa
--- /dev/null
+++ b/fs/yaffs2/yaffs_mtdif2.h
@@ -0,0 +1,29 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_MTDIF2_H__
+#define __YAFFS_MTDIF2_H__
+
+#include "yaffs_guts.h"
+int nandmtd2_WriteChunkWithTagsToNAND(yaffs_Device *dev, int chunkInNAND,
+				const __u8 *data,
+				const yaffs_ExtendedTags *tags);
+int nandmtd2_ReadChunkWithTagsFromNAND(yaffs_Device *dev, int chunkInNAND,
+				__u8 *data, yaffs_ExtendedTags *tags);
+int nandmtd2_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo);
+int nandmtd2_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo,
+			yaffs_BlockState *state, __u32 *sequenceNumber);
+
+#endif
diff --git a/fs/yaffs2/yaffs_nand.c b/fs/yaffs2/yaffs_nand.c
new file mode 100644
index 00000000000..6964ad18c0d
--- /dev/null
+++ b/fs/yaffs2/yaffs_nand.c
@@ -0,0 +1,140 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_nand.h"
+#include "yaffs_tagscompat.h"
+#include "yaffs_tagsvalidity.h"
+
+#include "yaffs_getblockinfo.h"
+
+int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device *dev, int chunkInNAND,
+					   __u8 *buffer,
+					   yaffs_ExtendedTags *tags)
+{
+	int result;
+	yaffs_ExtendedTags localTags;
+
+	int realignedChunkInNAND = chunkInNAND - dev->chunkOffset;
+
+	dev->nPageReads++;
+
+	/* If there are no tags provided, use local tags to get prioritised gc working */
+	if (!tags)
+		tags = &localTags;
+
+	if (dev->param.readChunkWithTagsFromNAND)
+		result = dev->param.readChunkWithTagsFromNAND(dev, realignedChunkInNAND, buffer,
+						      tags);
+	else
+		result = yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(dev,
+									realignedChunkInNAND,
+									buffer,
+									tags);
+	if (tags &&
+	   tags->eccResult > YAFFS_ECC_RESULT_NO_ERROR) {
+
+		yaffs_BlockInfo *bi;
+		bi = yaffs_GetBlockInfo(dev, chunkInNAND/dev->param.nChunksPerBlock);
+		yaffs_HandleChunkError(dev, bi);
+	}
+
+	return result;
+}
+
+int yaffs_WriteChunkWithTagsToNAND(yaffs_Device *dev,
+						   int chunkInNAND,
+						   const __u8 *buffer,
+						   yaffs_ExtendedTags *tags)
+{
+
+	dev->nPageWrites++;
+
+	chunkInNAND -= dev->chunkOffset;
+
+
+	if (tags) {
+		tags->sequenceNumber = dev->sequenceNumber;
+		tags->chunkUsed = 1;
+		if (!yaffs_ValidateTags(tags)) {
+			T(YAFFS_TRACE_ERROR,
+			  (TSTR("Writing uninitialised tags" TENDSTR)));
+			YBUG();
+		}
+		T(YAFFS_TRACE_WRITE,
+		  (TSTR("Writing chunk %d tags %d %d" TENDSTR), chunkInNAND,
+		   tags->objectId, tags->chunkId));
+	} else {
+		T(YAFFS_TRACE_ERROR, (TSTR("Writing with no tags" TENDSTR)));
+		YBUG();
+	}
+
+	if (dev->param.writeChunkWithTagsToNAND)
+		return dev->param.writeChunkWithTagsToNAND(dev, chunkInNAND, buffer,
+						     tags);
+	else
+		return yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(dev,
+								       chunkInNAND,
+								       buffer,
+								       tags);
+}
+
+int yaffs_MarkBlockBad(yaffs_Device *dev, int blockNo)
+{
+	blockNo -= dev->blockOffset;
+
+
+	if (dev->param.markNANDBlockBad)
+		return dev->param.markNANDBlockBad(dev, blockNo);
+	else
+		return yaffs_TagsCompatabilityMarkNANDBlockBad(dev, blockNo);
+}
+
+int yaffs_QueryInitialBlockState(yaffs_Device *dev,
+						 int blockNo,
+						 yaffs_BlockState *state,
+						 __u32 *sequenceNumber)
+{
+	blockNo -= dev->blockOffset;
+
+	if (dev->param.queryNANDBlock)
+		return dev->param.queryNANDBlock(dev, blockNo, state, sequenceNumber);
+	else
+		return yaffs_TagsCompatabilityQueryNANDBlock(dev, blockNo,
+							     state,
+							     sequenceNumber);
+}
+
+
+int yaffs_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,
+				  int blockInNAND)
+{
+	int result;
+
+	blockInNAND -= dev->blockOffset;
+
+	dev->nBlockErasures++;
+
+	result = dev->param.eraseBlockInNAND(dev, blockInNAND);
+
+	return result;
+}
+
+int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev)
+{
+	if(dev->param.initialiseNAND)
+		return dev->param.initialiseNAND(dev);
+	return YAFFS_OK;
+}
+
+
+
diff --git a/fs/yaffs2/yaffs_nand.h b/fs/yaffs2/yaffs_nand.h
new file mode 100644
index 00000000000..62a466596c5
--- /dev/null
+++ b/fs/yaffs2/yaffs_nand.h
@@ -0,0 +1,44 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_NAND_H__
+#define __YAFFS_NAND_H__
+#include "yaffs_guts.h"
+
+
+
+int yaffs_ReadChunkWithTagsFromNAND(yaffs_Device *dev, int chunkInNAND,
+					__u8 *buffer,
+					yaffs_ExtendedTags *tags);
+
+int yaffs_WriteChunkWithTagsToNAND(yaffs_Device *dev,
+						int chunkInNAND,
+						const __u8 *buffer,
+						yaffs_ExtendedTags *tags);
+
+int yaffs_MarkBlockBad(yaffs_Device *dev, int blockNo);
+
+int yaffs_QueryInitialBlockState(yaffs_Device *dev,
+						int blockNo,
+						yaffs_BlockState *state,
+						unsigned *sequenceNumber);
+
+int yaffs_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,
+				  int blockInNAND);
+
+int yaffs_InitialiseNAND(struct yaffs_DeviceStruct *dev);
+
+#endif
+
diff --git a/fs/yaffs2/yaffs_nandemul2k.h b/fs/yaffs2/yaffs_nandemul2k.h
new file mode 100644
index 00000000000..2f4ce97b22b
--- /dev/null
+++ b/fs/yaffs2/yaffs_nandemul2k.h
@@ -0,0 +1,39 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/* Interface to emulated NAND functions (2k page size) */
+
+#ifndef __YAFFS_NANDEMUL2K_H__
+#define __YAFFS_NANDEMUL2K_H__
+
+#include "yaffs_guts.h"
+
+int nandemul2k_WriteChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
+					int chunkInNAND, const __u8 *data,
+					const yaffs_ExtendedTags *tags);
+int nandemul2k_ReadChunkWithTagsFromNAND(struct yaffs_DeviceStruct *dev,
+					 int chunkInNAND, __u8 *data,
+					 yaffs_ExtendedTags *tags);
+int nandemul2k_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo);
+int nandemul2k_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo,
+			      yaffs_BlockState *state, __u32 *sequenceNumber);
+int nandemul2k_EraseBlockInNAND(struct yaffs_DeviceStruct *dev,
+				int blockInNAND);
+int nandemul2k_InitialiseNAND(struct yaffs_DeviceStruct *dev);
+int nandemul2k_GetBytesPerChunk(void);
+int nandemul2k_GetChunksPerBlock(void);
+int nandemul2k_GetNumberOfBlocks(void);
+
+#endif
diff --git a/fs/yaffs2/yaffs_packedtags1.c b/fs/yaffs2/yaffs_packedtags1.c
new file mode 100644
index 00000000000..b2160c08b60
--- /dev/null
+++ b/fs/yaffs2/yaffs_packedtags1.c
@@ -0,0 +1,50 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_packedtags1.h"
+#include "yportenv.h"
+
+void yaffs_PackTags1(yaffs_PackedTags1 *pt, const yaffs_ExtendedTags *t)
+{
+	pt->chunkId = t->chunkId;
+	pt->serialNumber = t->serialNumber;
+	pt->byteCount = t->byteCount;
+	pt->objectId = t->objectId;
+	pt->ecc = 0;
+	pt->deleted = (t->chunkDeleted) ? 0 : 1;
+	pt->unusedStuff = 0;
+	pt->shouldBeFF = 0xFFFFFFFF;
+
+}
+
+void yaffs_UnpackTags1(yaffs_ExtendedTags *t, const yaffs_PackedTags1 *pt)
+{
+	static const __u8 allFF[] =
+	    { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+0xff };
+
+	if (memcmp(allFF, pt, sizeof(yaffs_PackedTags1))) {
+		t->blockBad = 0;
+		if (pt->shouldBeFF != 0xFFFFFFFF)
+			t->blockBad = 1;
+		t->chunkUsed = 1;
+		t->objectId = pt->objectId;
+		t->chunkId = pt->chunkId;
+		t->byteCount = pt->byteCount;
+		t->eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+		t->chunkDeleted = (pt->deleted) ? 0 : 1;
+		t->serialNumber = pt->serialNumber;
+	} else {
+		memset(t, 0, sizeof(yaffs_ExtendedTags));
+	}
+}
diff --git a/fs/yaffs2/yaffs_packedtags1.h b/fs/yaffs2/yaffs_packedtags1.h
new file mode 100644
index 00000000000..b9cf1a8bfbc
--- /dev/null
+++ b/fs/yaffs2/yaffs_packedtags1.h
@@ -0,0 +1,37 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/* This is used to pack YAFFS1 tags, not YAFFS2 tags. */
+
+#ifndef __YAFFS_PACKEDTAGS1_H__
+#define __YAFFS_PACKEDTAGS1_H__
+
+#include "yaffs_guts.h"
+
+typedef struct {
+	unsigned chunkId:20;
+	unsigned serialNumber:2;
+	unsigned byteCount:10;
+	unsigned objectId:18;
+	unsigned ecc:12;
+	unsigned deleted:1;
+	unsigned unusedStuff:1;
+	unsigned shouldBeFF;
+
+} yaffs_PackedTags1;
+
+void yaffs_PackTags1(yaffs_PackedTags1 *pt, const yaffs_ExtendedTags *t);
+void yaffs_UnpackTags1(yaffs_ExtendedTags *t, const yaffs_PackedTags1 *pt);
+#endif
diff --git a/fs/yaffs2/yaffs_packedtags2.c b/fs/yaffs2/yaffs_packedtags2.c
new file mode 100644
index 00000000000..f8ae94ccddb
--- /dev/null
+++ b/fs/yaffs2/yaffs_packedtags2.c
@@ -0,0 +1,198 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_packedtags2.h"
+#include "yportenv.h"
+#include "yaffs_trace.h"
+#include "yaffs_tagsvalidity.h"
+
+/* This code packs a set of extended tags into a binary structure for
+ * NAND storage
+ */
+
+/* Some of the information is "extra" struff which can be packed in to
+ * speed scanning
+ * This is defined by having the EXTRA_HEADER_INFO_FLAG set.
+ */
+
+/* Extra flags applied to chunkId */
+
+#define EXTRA_HEADER_INFO_FLAG	0x80000000
+#define EXTRA_SHRINK_FLAG	0x40000000
+#define EXTRA_SHADOWS_FLAG	0x20000000
+#define EXTRA_SPARE_FLAGS	0x10000000
+
+#define ALL_EXTRA_FLAGS		0xF0000000
+
+/* Also, the top 4 bits of the object Id are set to the object type. */
+#define EXTRA_OBJECT_TYPE_SHIFT (28)
+#define EXTRA_OBJECT_TYPE_MASK  ((0x0F) << EXTRA_OBJECT_TYPE_SHIFT)
+
+
+static void yaffs_DumpPackedTags2TagsPart(const yaffs_PackedTags2TagsPart *ptt)
+{
+	T(YAFFS_TRACE_MTD,
+	  (TSTR("packed tags obj %d chunk %d byte %d seq %d" TENDSTR),
+	   ptt->objectId, ptt->chunkId, ptt->byteCount,
+	   ptt->sequenceNumber));
+}
+static void yaffs_DumpPackedTags2(const yaffs_PackedTags2 *pt)
+{
+	yaffs_DumpPackedTags2TagsPart(&pt->t);
+}
+
+static void yaffs_DumpTags2(const yaffs_ExtendedTags *t)
+{
+	T(YAFFS_TRACE_MTD,
+	  (TSTR
+	   ("ext.tags eccres %d blkbad %d chused %d obj %d chunk%d byte %d del %d ser %d seq %d"
+	    TENDSTR), t->eccResult, t->blockBad, t->chunkUsed, t->objectId,
+	   t->chunkId, t->byteCount, t->chunkDeleted, t->serialNumber,
+	   t->sequenceNumber));
+
+}
+
+void yaffs_PackTags2TagsPart(yaffs_PackedTags2TagsPart *ptt,
+		const yaffs_ExtendedTags *t)
+{
+	ptt->chunkId = t->chunkId;
+	ptt->sequenceNumber = t->sequenceNumber;
+	ptt->byteCount = t->byteCount;
+	ptt->objectId = t->objectId;
+
+	if (t->chunkId == 0 && t->extraHeaderInfoAvailable) {
+		/* Store the extra header info instead */
+		/* We save the parent object in the chunkId */
+		ptt->chunkId = EXTRA_HEADER_INFO_FLAG
+			| t->extraParentObjectId;
+		if (t->extraIsShrinkHeader)
+			ptt->chunkId |= EXTRA_SHRINK_FLAG;
+		if (t->extraShadows)
+			ptt->chunkId |= EXTRA_SHADOWS_FLAG;
+
+		ptt->objectId &= ~EXTRA_OBJECT_TYPE_MASK;
+		ptt->objectId |=
+		    (t->extraObjectType << EXTRA_OBJECT_TYPE_SHIFT);
+
+		if (t->extraObjectType == YAFFS_OBJECT_TYPE_HARDLINK)
+			ptt->byteCount = t->extraEquivalentObjectId;
+		else if (t->extraObjectType == YAFFS_OBJECT_TYPE_FILE)
+			ptt->byteCount = t->extraFileLength;
+		else
+			ptt->byteCount = 0;
+	}
+
+	yaffs_DumpPackedTags2TagsPart(ptt);
+	yaffs_DumpTags2(t);
+}
+
+
+void yaffs_PackTags2(yaffs_PackedTags2 *pt, const yaffs_ExtendedTags *t, int tagsECC)
+{
+	yaffs_PackTags2TagsPart(&pt->t, t);
+
+	if(tagsECC)
+		yaffs_ECCCalculateOther((unsigned char *)&pt->t,
+					sizeof(yaffs_PackedTags2TagsPart),
+					&pt->ecc);
+}
+
+
+void yaffs_UnpackTags2TagsPart(yaffs_ExtendedTags *t,
+		yaffs_PackedTags2TagsPart *ptt)
+{
+
+	memset(t, 0, sizeof(yaffs_ExtendedTags));
+
+	yaffs_InitialiseTags(t);
+
+	if (ptt->sequenceNumber != 0xFFFFFFFF) {
+		t->blockBad = 0;
+		t->chunkUsed = 1;
+		t->objectId = ptt->objectId;
+		t->chunkId = ptt->chunkId;
+		t->byteCount = ptt->byteCount;
+		t->chunkDeleted = 0;
+		t->serialNumber = 0;
+		t->sequenceNumber = ptt->sequenceNumber;
+
+		/* Do extra header info stuff */
+
+		if (ptt->chunkId & EXTRA_HEADER_INFO_FLAG) {
+			t->chunkId = 0;
+			t->byteCount = 0;
+
+			t->extraHeaderInfoAvailable = 1;
+			t->extraParentObjectId =
+			    ptt->chunkId & (~(ALL_EXTRA_FLAGS));
+			t->extraIsShrinkHeader =
+			    (ptt->chunkId & EXTRA_SHRINK_FLAG) ? 1 : 0;
+			t->extraShadows =
+			    (ptt->chunkId & EXTRA_SHADOWS_FLAG) ? 1 : 0;
+			t->extraObjectType =
+			    ptt->objectId >> EXTRA_OBJECT_TYPE_SHIFT;
+			t->objectId &= ~EXTRA_OBJECT_TYPE_MASK;
+
+			if (t->extraObjectType == YAFFS_OBJECT_TYPE_HARDLINK)
+				t->extraEquivalentObjectId = ptt->byteCount;
+			else
+				t->extraFileLength = ptt->byteCount;
+		}
+	}
+
+	yaffs_DumpPackedTags2TagsPart(ptt);
+	yaffs_DumpTags2(t);
+
+}
+
+
+void yaffs_UnpackTags2(yaffs_ExtendedTags *t, yaffs_PackedTags2 *pt, int tagsECC)
+{
+
+	yaffs_ECCResult eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+
+	if (pt->t.sequenceNumber != 0xFFFFFFFF &&
+	    tagsECC){
+		/* Chunk is in use and we need to do ECC */
+		
+		yaffs_ECCOther ecc;
+		int result;
+		yaffs_ECCCalculateOther((unsigned char *)&pt->t,
+					sizeof(yaffs_PackedTags2TagsPart),
+					&ecc);
+		result = yaffs_ECCCorrectOther((unsigned char *)&pt->t,
+						sizeof(yaffs_PackedTags2TagsPart),
+						&pt->ecc, &ecc);
+		switch (result) {
+			case 0:
+				eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+				break;
+			case 1:
+				eccResult = YAFFS_ECC_RESULT_FIXED;
+				break;
+			case -1:
+				eccResult = YAFFS_ECC_RESULT_UNFIXED;
+				break;
+			default:
+				eccResult = YAFFS_ECC_RESULT_UNKNOWN;
+		}
+	}
+
+	yaffs_UnpackTags2TagsPart(t, &pt->t);
+
+	t->eccResult = eccResult;
+
+	yaffs_DumpPackedTags2(pt);
+	yaffs_DumpTags2(t);
+}
+
diff --git a/fs/yaffs2/yaffs_packedtags2.h b/fs/yaffs2/yaffs_packedtags2.h
new file mode 100644
index 00000000000..c132a98cdc2
--- /dev/null
+++ b/fs/yaffs2/yaffs_packedtags2.h
@@ -0,0 +1,43 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/* This is used to pack YAFFS2 tags, not YAFFS1tags. */
+
+#ifndef __YAFFS_PACKEDTAGS2_H__
+#define __YAFFS_PACKEDTAGS2_H__
+
+#include "yaffs_guts.h"
+#include "yaffs_ecc.h"
+
+typedef struct {
+	unsigned sequenceNumber;
+	unsigned objectId;
+	unsigned chunkId;
+	unsigned byteCount;
+} yaffs_PackedTags2TagsPart;
+
+typedef struct {
+	yaffs_PackedTags2TagsPart t;
+	yaffs_ECCOther ecc;
+} yaffs_PackedTags2;
+
+/* Full packed tags with ECC, used for oob tags */
+void yaffs_PackTags2(yaffs_PackedTags2 *pt, const yaffs_ExtendedTags *t, int tagsECC);
+void yaffs_UnpackTags2(yaffs_ExtendedTags *t, yaffs_PackedTags2 *pt, int tagsECC);
+
+/* Only the tags part (no ECC for use with inband tags */
+void yaffs_PackTags2TagsPart(yaffs_PackedTags2TagsPart *pt, const yaffs_ExtendedTags *t);
+void yaffs_UnpackTags2TagsPart(yaffs_ExtendedTags *t, yaffs_PackedTags2TagsPart *pt);
+#endif
diff --git a/fs/yaffs2/yaffs_qsort.c b/fs/yaffs2/yaffs_qsort.c
new file mode 100644
index 00000000000..187519fbdb5
--- /dev/null
+++ b/fs/yaffs2/yaffs_qsort.c
@@ -0,0 +1,163 @@
+/*
+ * Copyright (c) 1992, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "yportenv.h"
+/* #include <linux/string.h> */
+
+/*
+ * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
+ */
+#define swapcode(TYPE, parmi, parmj, n) do { 		\
+	long i = (n) / sizeof (TYPE); 			\
+	register TYPE *pi = (TYPE *) (parmi); 		\
+	register TYPE *pj = (TYPE *) (parmj); 		\
+	do { 						\
+		register TYPE	t = *pi;		\
+		*pi++ = *pj;				\
+		*pj++ = t;				\
+	} while (--i > 0);				\
+} while (0)
+
+#define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \
+	es % sizeof(long) ? 2 : es == sizeof(long) ? 0 : 1;
+
+static __inline void
+swapfunc(char *a, char *b, int n, int swaptype)
+{
+	if (swaptype <= 1)
+		swapcode(long, a, b, n);
+	else
+		swapcode(char, a, b, n);
+}
+
+#define yswap(a, b) do {					\
+	if (swaptype == 0) {				\
+		long t = *(long *)(a);			\
+		*(long *)(a) = *(long *)(b);		\
+		*(long *)(b) = t;			\
+	} else						\
+		swapfunc(a, b, es, swaptype);		\
+} while (0)
+
+#define vecswap(a, b, n) 	if ((n) > 0) swapfunc(a, b, n, swaptype)
+
+static __inline char *
+med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *))
+{
+	return cmp(a, b) < 0 ?
+		(cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a))
+		: (cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c));
+}
+
+#ifndef min
+#define min(a, b) (((a) < (b)) ? (a) : (b))
+#endif
+
+void
+yaffs_qsort(void *aa, size_t n, size_t es,
+	int (*cmp)(const void *, const void *))
+{
+	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
+	int d, r, swaptype, swap_cnt;
+	register char *a = aa;
+
+loop:	SWAPINIT(a, es);
+	swap_cnt = 0;
+	if (n < 7) {
+		for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es)
+			for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
+			     pl -= es)
+				yswap(pl, pl - es);
+		return;
+	}
+	pm = (char *)a + (n / 2) * es;
+	if (n > 7) {
+		pl = (char *)a;
+		pn = (char *)a + (n - 1) * es;
+		if (n > 40) {
+			d = (n / 8) * es;
+			pl = med3(pl, pl + d, pl + 2 * d, cmp);
+			pm = med3(pm - d, pm, pm + d, cmp);
+			pn = med3(pn - 2 * d, pn - d, pn, cmp);
+		}
+		pm = med3(pl, pm, pn, cmp);
+	}
+	yswap(a, pm);
+	pa = pb = (char *)a + es;
+
+	pc = pd = (char *)a + (n - 1) * es;
+	for (;;) {
+		while (pb <= pc && (r = cmp(pb, a)) <= 0) {
+			if (r == 0) {
+				swap_cnt = 1;
+				yswap(pa, pb);
+				pa += es;
+			}
+			pb += es;
+		}
+		while (pb <= pc && (r = cmp(pc, a)) >= 0) {
+			if (r == 0) {
+				swap_cnt = 1;
+				yswap(pc, pd);
+				pd -= es;
+			}
+			pc -= es;
+		}
+		if (pb > pc)
+			break;
+		yswap(pb, pc);
+		swap_cnt = 1;
+		pb += es;
+		pc -= es;
+	}
+	if (swap_cnt == 0) {  /* Switch to insertion sort */
+		for (pm = (char *) a + es; pm < (char *) a + n * es; pm += es)
+			for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
+			     pl -= es)
+				yswap(pl, pl - es);
+		return;
+	}
+
+	pn = (char *)a + n * es;
+	r = min(pa - (char *)a, pb - pa);
+	vecswap(a, pb - r, r);
+	r = min((long)(pd - pc), (long)(pn - pd - es));
+	vecswap(pb, pn - r, r);
+	r = pb - pa;
+	if (r > es)
+		yaffs_qsort(a, r / es, es, cmp);
+	r = pd - pc;
+	if (r > es) {
+		/* Iterate rather than recurse to save stack space */
+		a = pn - r;
+		n = r / es;
+		goto loop;
+	}
+/*		yaffs_qsort(pn - r, r / es, es, cmp);*/
+}
diff --git a/fs/yaffs2/yaffs_qsort.h b/fs/yaffs2/yaffs_qsort.h
new file mode 100644
index 00000000000..a24d58e3758
--- /dev/null
+++ b/fs/yaffs2/yaffs_qsort.h
@@ -0,0 +1,23 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YAFFS_QSORT_H__
+#define __YAFFS_QSORT_H__
+
+extern void yaffs_qsort(void *const base, size_t total_elems, size_t size,
+			int (*cmp)(const void *, const void *));
+
+#endif
diff --git a/fs/yaffs2/yaffs_tagscompat.c b/fs/yaffs2/yaffs_tagscompat.c
new file mode 100644
index 00000000000..e9ac51d7f94
--- /dev/null
+++ b/fs/yaffs2/yaffs_tagscompat.c
@@ -0,0 +1,539 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_guts.h"
+#include "yaffs_tagscompat.h"
+#include "yaffs_ecc.h"
+#include "yaffs_getblockinfo.h"
+#include "yaffs_trace.h"
+
+static void yaffs_HandleReadDataError(yaffs_Device *dev, int chunkInNAND);
+#ifdef NOTYET
+static void yaffs_CheckWrittenBlock(yaffs_Device *dev, int chunkInNAND);
+static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
+				     const __u8 *data,
+				     const yaffs_Spare *spare);
+static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
+				    const yaffs_Spare *spare);
+static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND);
+#endif
+
+static const char yaffs_countBitsTable[256] = {
+	0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+	4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
+};
+
+int yaffs_CountBits(__u8 x)
+{
+	int retVal;
+	retVal = yaffs_countBitsTable[x];
+	return retVal;
+}
+
+/********** Tags ECC calculations  *********/
+
+void yaffs_CalcECC(const __u8 *data, yaffs_Spare *spare)
+{
+	yaffs_ECCCalculate(data, spare->ecc1);
+	yaffs_ECCCalculate(&data[256], spare->ecc2);
+}
+
+void yaffs_CalcTagsECC(yaffs_Tags *tags)
+{
+	/* Calculate an ecc */
+
+	unsigned char *b = ((yaffs_TagsUnion *) tags)->asBytes;
+	unsigned i, j;
+	unsigned ecc = 0;
+	unsigned bit = 0;
+
+	tags->ecc = 0;
+
+	for (i = 0; i < 8; i++) {
+		for (j = 1; j & 0xff; j <<= 1) {
+			bit++;
+			if (b[i] & j)
+				ecc ^= bit;
+		}
+	}
+
+	tags->ecc = ecc;
+
+}
+
+int yaffs_CheckECCOnTags(yaffs_Tags *tags)
+{
+	unsigned ecc = tags->ecc;
+
+	yaffs_CalcTagsECC(tags);
+
+	ecc ^= tags->ecc;
+
+	if (ecc && ecc <= 64) {
+		/* TODO: Handle the failure better. Retire? */
+		unsigned char *b = ((yaffs_TagsUnion *) tags)->asBytes;
+
+		ecc--;
+
+		b[ecc / 8] ^= (1 << (ecc & 7));
+
+		/* Now recvalc the ecc */
+		yaffs_CalcTagsECC(tags);
+
+		return 1;	/* recovered error */
+	} else if (ecc) {
+		/* Wierd ecc failure value */
+		/* TODO Need to do somethiong here */
+		return -1;	/* unrecovered error */
+	}
+
+	return 0;
+}
+
+/********** Tags **********/
+
+static void yaffs_LoadTagsIntoSpare(yaffs_Spare *sparePtr,
+				yaffs_Tags *tagsPtr)
+{
+	yaffs_TagsUnion *tu = (yaffs_TagsUnion *) tagsPtr;
+
+	yaffs_CalcTagsECC(tagsPtr);
+
+	sparePtr->tagByte0 = tu->asBytes[0];
+	sparePtr->tagByte1 = tu->asBytes[1];
+	sparePtr->tagByte2 = tu->asBytes[2];
+	sparePtr->tagByte3 = tu->asBytes[3];
+	sparePtr->tagByte4 = tu->asBytes[4];
+	sparePtr->tagByte5 = tu->asBytes[5];
+	sparePtr->tagByte6 = tu->asBytes[6];
+	sparePtr->tagByte7 = tu->asBytes[7];
+}
+
+static void yaffs_GetTagsFromSpare(yaffs_Device *dev, yaffs_Spare *sparePtr,
+				yaffs_Tags *tagsPtr)
+{
+	yaffs_TagsUnion *tu = (yaffs_TagsUnion *) tagsPtr;
+	int result;
+
+	tu->asBytes[0] = sparePtr->tagByte0;
+	tu->asBytes[1] = sparePtr->tagByte1;
+	tu->asBytes[2] = sparePtr->tagByte2;
+	tu->asBytes[3] = sparePtr->tagByte3;
+	tu->asBytes[4] = sparePtr->tagByte4;
+	tu->asBytes[5] = sparePtr->tagByte5;
+	tu->asBytes[6] = sparePtr->tagByte6;
+	tu->asBytes[7] = sparePtr->tagByte7;
+
+	result = yaffs_CheckECCOnTags(tagsPtr);
+	if (result > 0)
+		dev->tagsEccFixed++;
+	else if (result < 0)
+		dev->tagsEccUnfixed++;
+}
+
+static void yaffs_SpareInitialise(yaffs_Spare *spare)
+{
+	memset(spare, 0xFF, sizeof(yaffs_Spare));
+}
+
+static int yaffs_WriteChunkToNAND(struct yaffs_DeviceStruct *dev,
+				int chunkInNAND, const __u8 *data,
+				yaffs_Spare *spare)
+{
+	if (chunkInNAND < dev->param.startBlock * dev->param.nChunksPerBlock) {
+		T(YAFFS_TRACE_ERROR,
+		  (TSTR("**>> yaffs chunk %d is not valid" TENDSTR),
+		   chunkInNAND));
+		return YAFFS_FAIL;
+	}
+
+	return dev->param.writeChunkToNAND(dev, chunkInNAND, data, spare);
+}
+
+static int yaffs_ReadChunkFromNAND(struct yaffs_DeviceStruct *dev,
+				   int chunkInNAND,
+				   __u8 *data,
+				   yaffs_Spare *spare,
+				   yaffs_ECCResult *eccResult,
+				   int doErrorCorrection)
+{
+	int retVal;
+	yaffs_Spare localSpare;
+
+	if (!spare && data) {
+		/* If we don't have a real spare, then we use a local one. */
+		/* Need this for the calculation of the ecc */
+		spare = &localSpare;
+	}
+
+	if (!dev->param.useNANDECC) {
+		retVal = dev->param.readChunkFromNAND(dev, chunkInNAND, data, spare);
+		if (data && doErrorCorrection) {
+			/* Do ECC correction */
+			/* Todo handle any errors */
+			int eccResult1, eccResult2;
+			__u8 calcEcc[3];
+
+			yaffs_ECCCalculate(data, calcEcc);
+			eccResult1 =
+			    yaffs_ECCCorrect(data, spare->ecc1, calcEcc);
+			yaffs_ECCCalculate(&data[256], calcEcc);
+			eccResult2 =
+			    yaffs_ECCCorrect(&data[256], spare->ecc2, calcEcc);
+
+			if (eccResult1 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error fix performed on chunk %d:0"
+				    TENDSTR), chunkInNAND));
+				dev->eccFixed++;
+			} else if (eccResult1 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error unfixed on chunk %d:0"
+				    TENDSTR), chunkInNAND));
+				dev->eccUnfixed++;
+			}
+
+			if (eccResult2 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error fix performed on chunk %d:1"
+				    TENDSTR), chunkInNAND));
+				dev->eccFixed++;
+			} else if (eccResult2 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>yaffs ecc error unfixed on chunk %d:1"
+				    TENDSTR), chunkInNAND));
+				dev->eccUnfixed++;
+			}
+
+			if (eccResult1 || eccResult2) {
+				/* We had a data problem on this page */
+				yaffs_HandleReadDataError(dev, chunkInNAND);
+			}
+
+			if (eccResult1 < 0 || eccResult2 < 0)
+				*eccResult = YAFFS_ECC_RESULT_UNFIXED;
+			else if (eccResult1 > 0 || eccResult2 > 0)
+				*eccResult = YAFFS_ECC_RESULT_FIXED;
+			else
+				*eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+		}
+	} else {
+		/* Must allocate enough memory for spare+2*sizeof(int) */
+		/* for ecc results from device. */
+		struct yaffs_NANDSpare nspare;
+
+		memset(&nspare, 0, sizeof(nspare));
+
+		retVal = dev->param.readChunkFromNAND(dev, chunkInNAND, data,
+					(yaffs_Spare *) &nspare);
+		memcpy(spare, &nspare, sizeof(yaffs_Spare));
+		if (data && doErrorCorrection) {
+			if (nspare.eccres1 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error fix performed on chunk %d:0"
+				    TENDSTR), chunkInNAND));
+			} else if (nspare.eccres1 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error unfixed on chunk %d:0"
+				    TENDSTR), chunkInNAND));
+			}
+
+			if (nspare.eccres2 > 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error fix performed on chunk %d:1"
+				    TENDSTR), chunkInNAND));
+			} else if (nspare.eccres2 < 0) {
+				T(YAFFS_TRACE_ERROR,
+				  (TSTR
+				   ("**>>mtd ecc error unfixed on chunk %d:1"
+				    TENDSTR), chunkInNAND));
+			}
+
+			if (nspare.eccres1 || nspare.eccres2) {
+				/* We had a data problem on this page */
+				yaffs_HandleReadDataError(dev, chunkInNAND);
+			}
+
+			if (nspare.eccres1 < 0 || nspare.eccres2 < 0)
+				*eccResult = YAFFS_ECC_RESULT_UNFIXED;
+			else if (nspare.eccres1 > 0 || nspare.eccres2 > 0)
+				*eccResult = YAFFS_ECC_RESULT_FIXED;
+			else
+				*eccResult = YAFFS_ECC_RESULT_NO_ERROR;
+
+		}
+	}
+	return retVal;
+}
+
+#ifdef NOTYET
+static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
+				  int chunkInNAND)
+{
+	static int init;
+	static __u8 cmpbuf[YAFFS_BYTES_PER_CHUNK];
+	static __u8 data[YAFFS_BYTES_PER_CHUNK];
+	/* Might as well always allocate the larger size for */
+	/* dev->param.useNANDECC == true; */
+	static __u8 spare[sizeof(struct yaffs_NANDSpare)];
+
+	dev->param.readChunkFromNAND(dev, chunkInNAND, data, (yaffs_Spare *) spare);
+
+	if (!init) {
+		memset(cmpbuf, 0xff, YAFFS_BYTES_PER_CHUNK);
+		init = 1;
+	}
+
+	if (memcmp(cmpbuf, data, YAFFS_BYTES_PER_CHUNK))
+		return YAFFS_FAIL;
+	if (memcmp(cmpbuf, spare, 16))
+		return YAFFS_FAIL;
+
+	return YAFFS_OK;
+
+}
+#endif
+
+/*
+ * Functions for robustisizing
+ */
+
+static void yaffs_HandleReadDataError(yaffs_Device *dev, int chunkInNAND)
+{
+	int blockInNAND = chunkInNAND / dev->param.nChunksPerBlock;
+
+	/* Mark the block for retirement */
+	yaffs_GetBlockInfo(dev, blockInNAND + dev->blockOffset)->needsRetiring = 1;
+	T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
+	  (TSTR("**>>Block %d marked for retirement" TENDSTR), blockInNAND));
+
+	/* TODO:
+	 * Just do a garbage collection on the affected block
+	 * then retire the block
+	 * NB recursion
+	 */
+}
+
+#ifdef NOTYET
+static void yaffs_CheckWrittenBlock(yaffs_Device *dev, int chunkInNAND)
+{
+}
+
+static void yaffs_HandleWriteChunkOk(yaffs_Device *dev, int chunkInNAND,
+				     const __u8 *data,
+				     const yaffs_Spare *spare)
+{
+}
+
+static void yaffs_HandleUpdateChunk(yaffs_Device *dev, int chunkInNAND,
+				    const yaffs_Spare *spare)
+{
+}
+
+static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND)
+{
+	int blockInNAND = chunkInNAND / dev->param.nChunksPerBlock;
+
+	/* Mark the block for retirement */
+	yaffs_GetBlockInfo(dev, blockInNAND)->needsRetiring = 1;
+	/* Delete the chunk */
+	yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
+}
+
+static int yaffs_VerifyCompare(const __u8 *d0, const __u8 *d1,
+			       const yaffs_Spare *s0, const yaffs_Spare *s1)
+{
+
+	if (memcmp(d0, d1, YAFFS_BYTES_PER_CHUNK) != 0 ||
+	    s0->tagByte0 != s1->tagByte0 ||
+	    s0->tagByte1 != s1->tagByte1 ||
+	    s0->tagByte2 != s1->tagByte2 ||
+	    s0->tagByte3 != s1->tagByte3 ||
+	    s0->tagByte4 != s1->tagByte4 ||
+	    s0->tagByte5 != s1->tagByte5 ||
+	    s0->tagByte6 != s1->tagByte6 ||
+	    s0->tagByte7 != s1->tagByte7 ||
+	    s0->ecc1[0] != s1->ecc1[0] ||
+	    s0->ecc1[1] != s1->ecc1[1] ||
+	    s0->ecc1[2] != s1->ecc1[2] ||
+	    s0->ecc2[0] != s1->ecc2[0] ||
+	    s0->ecc2[1] != s1->ecc2[1] || s0->ecc2[2] != s1->ecc2[2]) {
+		return 0;
+	}
+
+	return 1;
+}
+#endif				/* NOTYET */
+
+int yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(yaffs_Device *dev,
+						int chunkInNAND,
+						const __u8 *data,
+						const yaffs_ExtendedTags *eTags)
+{
+	yaffs_Spare spare;
+	yaffs_Tags tags;
+
+	yaffs_SpareInitialise(&spare);
+
+	if (eTags->chunkDeleted)
+		spare.pageStatus = 0;
+	else {
+		tags.objectId = eTags->objectId;
+		tags.chunkId = eTags->chunkId;
+
+		tags.byteCountLSB = eTags->byteCount & 0x3ff;
+
+		if (dev->nDataBytesPerChunk >= 1024)
+			tags.byteCountMSB = (eTags->byteCount >> 10) & 3;
+		else
+			tags.byteCountMSB = 3;
+
+
+		tags.serialNumber = eTags->serialNumber;
+
+		if (!dev->param.useNANDECC && data)
+			yaffs_CalcECC(data, &spare);
+
+		yaffs_LoadTagsIntoSpare(&spare, &tags);
+
+	}
+
+	return yaffs_WriteChunkToNAND(dev, chunkInNAND, data, &spare);
+}
+
+int yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(yaffs_Device *dev,
+						     int chunkInNAND,
+						     __u8 *data,
+						     yaffs_ExtendedTags *eTags)
+{
+
+	yaffs_Spare spare;
+	yaffs_Tags tags;
+	yaffs_ECCResult eccResult = YAFFS_ECC_RESULT_UNKNOWN;
+
+	static yaffs_Spare spareFF;
+	static int init;
+
+	if (!init) {
+		memset(&spareFF, 0xFF, sizeof(spareFF));
+		init = 1;
+	}
+
+	if (yaffs_ReadChunkFromNAND
+	    (dev, chunkInNAND, data, &spare, &eccResult, 1)) {
+		/* eTags may be NULL */
+		if (eTags) {
+
+			int deleted =
+			    (yaffs_CountBits(spare.pageStatus) < 7) ? 1 : 0;
+
+			eTags->chunkDeleted = deleted;
+			eTags->eccResult = eccResult;
+			eTags->blockBad = 0;	/* We're reading it */
+			/* therefore it is not a bad block */
+			eTags->chunkUsed =
+			    (memcmp(&spareFF, &spare, sizeof(spareFF)) !=
+			     0) ? 1 : 0;
+
+			if (eTags->chunkUsed) {
+				yaffs_GetTagsFromSpare(dev, &spare, &tags);
+
+				eTags->objectId = tags.objectId;
+				eTags->chunkId = tags.chunkId;
+				eTags->byteCount = tags.byteCountLSB;
+
+				if (dev->nDataBytesPerChunk >= 1024)
+					eTags->byteCount |= (((unsigned) tags.byteCountMSB) << 10);
+
+				eTags->serialNumber = tags.serialNumber;
+			}
+		}
+
+		return YAFFS_OK;
+	} else {
+		return YAFFS_FAIL;
+	}
+}
+
+int yaffs_TagsCompatabilityMarkNANDBlockBad(struct yaffs_DeviceStruct *dev,
+					    int blockInNAND)
+{
+
+	yaffs_Spare spare;
+
+	memset(&spare, 0xff, sizeof(yaffs_Spare));
+
+	spare.blockStatus = 'Y';
+
+	yaffs_WriteChunkToNAND(dev, blockInNAND * dev->param.nChunksPerBlock, NULL,
+			       &spare);
+	yaffs_WriteChunkToNAND(dev, blockInNAND * dev->param.nChunksPerBlock + 1,
+			       NULL, &spare);
+
+	return YAFFS_OK;
+
+}
+
+int yaffs_TagsCompatabilityQueryNANDBlock(struct yaffs_DeviceStruct *dev,
+					  int blockNo,
+					  yaffs_BlockState *state,
+					  __u32 *sequenceNumber)
+{
+
+	yaffs_Spare spare0, spare1;
+	static yaffs_Spare spareFF;
+	static int init;
+	yaffs_ECCResult dummy;
+
+	if (!init) {
+		memset(&spareFF, 0xFF, sizeof(spareFF));
+		init = 1;
+	}
+
+	*sequenceNumber = 0;
+
+	yaffs_ReadChunkFromNAND(dev, blockNo * dev->param.nChunksPerBlock, NULL,
+				&spare0, &dummy, 1);
+	yaffs_ReadChunkFromNAND(dev, blockNo * dev->param.nChunksPerBlock + 1, NULL,
+				&spare1, &dummy, 1);
+
+	if (yaffs_CountBits(spare0.blockStatus & spare1.blockStatus) < 7)
+		*state = YAFFS_BLOCK_STATE_DEAD;
+	else if (memcmp(&spareFF, &spare0, sizeof(spareFF)) == 0)
+		*state = YAFFS_BLOCK_STATE_EMPTY;
+	else
+		*state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+
+	return YAFFS_OK;
+}
diff --git a/fs/yaffs2/yaffs_tagscompat.h b/fs/yaffs2/yaffs_tagscompat.h
new file mode 100644
index 00000000000..8c663db526c
--- /dev/null
+++ b/fs/yaffs2/yaffs_tagscompat.h
@@ -0,0 +1,39 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFS_TAGSCOMPAT_H__
+#define __YAFFS_TAGSCOMPAT_H__
+
+#include "yaffs_guts.h"
+int yaffs_TagsCompatabilityWriteChunkWithTagsToNAND(yaffs_Device *dev,
+						int chunkInNAND,
+						const __u8 *data,
+						const yaffs_ExtendedTags *tags);
+int yaffs_TagsCompatabilityReadChunkWithTagsFromNAND(yaffs_Device *dev,
+						int chunkInNAND,
+						__u8 *data,
+						yaffs_ExtendedTags *tags);
+int yaffs_TagsCompatabilityMarkNANDBlockBad(struct yaffs_DeviceStruct *dev,
+					    int blockNo);
+int yaffs_TagsCompatabilityQueryNANDBlock(struct yaffs_DeviceStruct *dev,
+					  int blockNo,
+					  yaffs_BlockState *state,
+					  __u32 *sequenceNumber);
+
+void yaffs_CalcTagsECC(yaffs_Tags *tags);
+int yaffs_CheckECCOnTags(yaffs_Tags *tags);
+int yaffs_CountBits(__u8 byte);
+
+#endif
diff --git a/fs/yaffs2/yaffs_tagsvalidity.c b/fs/yaffs2/yaffs_tagsvalidity.c
new file mode 100644
index 00000000000..93ad08c1f5d
--- /dev/null
+++ b/fs/yaffs2/yaffs_tagsvalidity.c
@@ -0,0 +1,28 @@
+/*
+ * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "yaffs_tagsvalidity.h"
+
+void yaffs_InitialiseTags(yaffs_ExtendedTags *tags)
+{
+	memset(tags, 0, sizeof(yaffs_ExtendedTags));
+	tags->validMarker0 = 0xAAAAAAAA;
+	tags->validMarker1 = 0x55555555;
+}
+
+int yaffs_ValidateTags(yaffs_ExtendedTags *tags)
+{
+	return (tags->validMarker0 == 0xAAAAAAAA &&
+		tags->validMarker1 == 0x55555555);
+
+}
diff --git a/fs/yaffs2/yaffs_tagsvalidity.h b/fs/yaffs2/yaffs_tagsvalidity.h
new file mode 100644
index 00000000000..60a1aea6c5c
--- /dev/null
+++ b/fs/yaffs2/yaffs_tagsvalidity.h
@@ -0,0 +1,24 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YAFFS_TAGS_VALIDITY_H__
+#define __YAFFS_TAGS_VALIDITY_H__
+
+#include "yaffs_guts.h"
+
+void yaffs_InitialiseTags(yaffs_ExtendedTags *tags);
+int yaffs_ValidateTags(yaffs_ExtendedTags *tags);
+#endif
diff --git a/fs/yaffs2/yaffs_trace.h b/fs/yaffs2/yaffs_trace.h
new file mode 100644
index 00000000000..8b848edba05
--- /dev/null
+++ b/fs/yaffs2/yaffs_trace.h
@@ -0,0 +1,60 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YTRACE_H__
+#define __YTRACE_H__
+
+extern unsigned int yaffs_traceMask;
+extern unsigned int yaffs_wr_attempts;
+
+/*
+ * Tracing flags.
+ * The flags masked in YAFFS_TRACE_ALWAYS are always traced.
+ */
+
+#define YAFFS_TRACE_OS			0x00000002
+#define YAFFS_TRACE_ALLOCATE		0x00000004
+#define YAFFS_TRACE_SCAN		0x00000008
+#define YAFFS_TRACE_BAD_BLOCKS		0x00000010
+#define YAFFS_TRACE_ERASE		0x00000020
+#define YAFFS_TRACE_GC			0x00000040
+#define YAFFS_TRACE_WRITE		0x00000080
+#define YAFFS_TRACE_TRACING		0x00000100
+#define YAFFS_TRACE_DELETION		0x00000200
+#define YAFFS_TRACE_BUFFERS		0x00000400
+#define YAFFS_TRACE_NANDACCESS		0x00000800
+#define YAFFS_TRACE_GC_DETAIL		0x00001000
+#define YAFFS_TRACE_SCAN_DEBUG		0x00002000
+#define YAFFS_TRACE_MTD			0x00004000
+#define YAFFS_TRACE_CHECKPOINT		0x00008000
+
+#define YAFFS_TRACE_VERIFY		0x00010000
+#define YAFFS_TRACE_VERIFY_NAND		0x00020000
+#define YAFFS_TRACE_VERIFY_FULL		0x00040000
+#define YAFFS_TRACE_VERIFY_ALL		0x000F0000
+
+#define YAFFS_TRACE_SYNC		0x00100000
+#define YAFFS_TRACE_BACKGROUND		0x00200000
+#define YAFFS_TRACE_LOCK		0x00400000
+
+#define YAFFS_TRACE_ERROR		0x40000000
+#define YAFFS_TRACE_BUG			0x80000000
+#define YAFFS_TRACE_ALWAYS		0xF0000000
+
+
+#define T(mask, p) do { if ((mask) & (yaffs_traceMask | YAFFS_TRACE_ALWAYS)) TOUT(p); } while (0)
+
+#endif
diff --git a/fs/yaffs2/yaffsinterface.h b/fs/yaffs2/yaffsinterface.h
new file mode 100644
index 00000000000..ca36cfc427a
--- /dev/null
+++ b/fs/yaffs2/yaffsinterface.h
@@ -0,0 +1,21 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+#ifndef __YAFFSINTERFACE_H__
+#define __YAFFSINTERFACE_H__
+
+int yaffs_Initialise(unsigned nBlocks);
+
+#endif
diff --git a/fs/yaffs2/yportenv.h b/fs/yaffs2/yportenv.h
new file mode 100644
index 00000000000..13cc1eb6217
--- /dev/null
+++ b/fs/yaffs2/yportenv.h
@@ -0,0 +1,169 @@
+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2010 Aleph One Ltd.
+ *   for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+
+#ifndef __YPORTENV_H__
+#define __YPORTENV_H__
+
+/*
+ * Define the MTD version in terms of Linux Kernel versions
+ * This allows yaffs to be used independantly of the kernel
+ * as well as with it.
+ */
+
+#define MTD_VERSION(a, b, c) (((a) << 16) + ((b) << 8) + (c))
+
+#if defined CONFIG_YAFFS_WINCE
+
+#include "ywinceenv.h"
+
+#elif defined __KERNEL__
+
+#include "moduleconfig.h"
+
+/* Linux kernel */
+
+#include <linux/version.h>
+#define MTD_VERSION_CODE LINUX_VERSION_CODE
+
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 19))
+#include <linux/config.h>
+#endif
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#define YCHAR char
+#define YUCHAR unsigned char
+#define _Y(x)     x
+#define yaffs_strcat(a, b)     strcat(a, b)
+#define yaffs_strcpy(a, b)     strcpy(a, b)
+#define yaffs_strncpy(a, b, c) strncpy(a, b, c)
+#define yaffs_strncmp(a, b, c) strncmp(a, b, c)
+#define yaffs_strnlen(s,m)	strnlen(s,m)
+#define yaffs_sprintf	       sprintf
+#define yaffs_toupper(a)       toupper(a)
+
+#define Y_INLINE inline
+
+#define YAFFS_LOSTNFOUND_NAME		"lost+found"
+#define YAFFS_LOSTNFOUND_PREFIX		"obj"
+
+/* #define YPRINTF(x) printk x */
+#define YMALLOC(x) kmalloc(x, GFP_NOFS)
+#define YFREE(x)   kfree(x)
+#define YMALLOC_ALT(x) vmalloc(x)
+#define YFREE_ALT(x)   vfree(x)
+#define YMALLOC_DMA(x) YMALLOC(x)
+
+#define YYIELD() schedule()
+#define Y_DUMP_STACK() dump_stack()
+
+#define YAFFS_ROOT_MODE			0755
+#define YAFFS_LOSTNFOUND_MODE		0700
+
+#if (LINUX_VERSION_CODE > KERNEL_VERSION(2, 5, 0))
+#define Y_CURRENT_TIME CURRENT_TIME.tv_sec
+#define Y_TIME_CONVERT(x) (x).tv_sec
+#else
+#define Y_CURRENT_TIME CURRENT_TIME
+#define Y_TIME_CONVERT(x) (x)
+#endif
+
+#define yaffs_SumCompare(x, y) ((x) == (y))
+#define yaffs_strcmp(a, b) strcmp(a, b)
+
+#define TENDSTR "\n"
+#define TSTR(x) KERN_DEBUG x
+#define TCONT(x) x
+#define TOUT(p) printk p
+
+#define compile_time_assertion(assertion) \
+	({ int x = __builtin_choose_expr(assertion, 0, (void)0); (void) x; })
+
+#elif defined CONFIG_YAFFS_DIRECT
+
+#define MTD_VERSION_CODE MTD_VERSION(2, 6, 22)
+
+/* Direct interface */
+#include "ydirectenv.h"
+
+#elif defined CONFIG_YAFFS_UTIL
+
+/* Stuff for YAFFS utilities */
+
+#include "stdlib.h"
+#include "stdio.h"
+#include "string.h"
+
+#include "devextras.h"
+
+#define YMALLOC(x) malloc(x)
+#define YFREE(x)   free(x)
+#define YMALLOC_ALT(x) malloc(x)
+#define YFREE_ALT(x) free(x)
+
+#define YCHAR char
+#define YUCHAR unsigned char
+#define _Y(x)     x
+#define yaffs_strcat(a, b)     strcat(a, b)
+#define yaffs_strcpy(a, b)     strcpy(a, b)
+#define yaffs_strncpy(a, b, c) strncpy(a, b, c)
+#define yaffs_strnlen(s,m)	       strnlen(s,m)
+#define yaffs_sprintf	       sprintf
+#define yaffs_toupper(a)       toupper(a)
+
+#define Y_INLINE inline
+
+/* #define YINFO(s) YPRINTF(( __FILE__ " %d %s\n",__LINE__,s)) */
+/* #define YALERT(s) YINFO(s) */
+
+#define TENDSTR "\n"
+#define TSTR(x) x
+#define TOUT(p) printf p
+
+#define YAFFS_LOSTNFOUND_NAME		"lost+found"
+#define YAFFS_LOSTNFOUND_PREFIX		"obj"
+/* #define YPRINTF(x) printf x */
+
+#define YAFFS_ROOT_MODE			0755
+#define YAFFS_LOSTNFOUND_MODE		0700
+
+#define yaffs_SumCompare(x, y) ((x) == (y))
+#define yaffs_strcmp(a, b) strcmp(a, b)
+
+#else
+/* Should have specified a configuration type */
+#error Unknown configuration
+
+#endif
+
+#ifndef Y_DUMP_STACK
+#define Y_DUMP_STACK() do { } while (0)
+#endif
+
+#ifndef YBUG
+#define YBUG() do {\
+	T(YAFFS_TRACE_BUG,\
+		(TSTR("==>> yaffs bug: " __FILE__ " %d" TENDSTR),\
+		__LINE__));\
+	Y_DUMP_STACK();\
+} while (0)
+#endif
+
+#endif