diff options
Diffstat (limited to 'contrib/linux-kernel/fs/btrfs/zstd.c')
-rw-r--r-- | contrib/linux-kernel/fs/btrfs/zstd.c | 432 |
1 files changed, 0 insertions, 432 deletions
diff --git a/contrib/linux-kernel/fs/btrfs/zstd.c b/contrib/linux-kernel/fs/btrfs/zstd.c deleted file mode 100644 index 607ce47b..00000000 --- a/contrib/linux-kernel/fs/btrfs/zstd.c +++ /dev/null @@ -1,432 +0,0 @@ -/* - * Copyright (c) 2016-present, Facebook, Inc. - * All rights reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public - * License v2 as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - */ -#include <linux/bio.h> -#include <linux/err.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/mm.h> -#include <linux/pagemap.h> -#include <linux/refcount.h> -#include <linux/sched.h> -#include <linux/slab.h> -#include <linux/zstd.h> -#include "compression.h" - -#define ZSTD_BTRFS_MAX_WINDOWLOG 17 -#define ZSTD_BTRFS_MAX_INPUT (1 << ZSTD_BTRFS_MAX_WINDOWLOG) -#define ZSTD_BTRFS_DEFAULT_LEVEL 3 - -static ZSTD_parameters zstd_get_btrfs_parameters(size_t src_len) -{ - ZSTD_parameters params = ZSTD_getParams(ZSTD_BTRFS_DEFAULT_LEVEL, - src_len, 0); - - if (params.cParams.windowLog > ZSTD_BTRFS_MAX_WINDOWLOG) - params.cParams.windowLog = ZSTD_BTRFS_MAX_WINDOWLOG; - WARN_ON(src_len > ZSTD_BTRFS_MAX_INPUT); - return params; -} - -struct workspace { - void *mem; - size_t size; - char *buf; - struct list_head list; -}; - -static void zstd_free_workspace(struct list_head *ws) -{ - struct workspace *workspace = list_entry(ws, struct workspace, list); - - kvfree(workspace->mem); - kfree(workspace->buf); - kfree(workspace); -} - -static struct list_head *zstd_alloc_workspace(void) -{ - ZSTD_parameters params = - zstd_get_btrfs_parameters(ZSTD_BTRFS_MAX_INPUT); - struct workspace *workspace; - - workspace = kzalloc(sizeof(*workspace), GFP_KERNEL); - if (!workspace) - return ERR_PTR(-ENOMEM); - - workspace->size = max_t(size_t, - ZSTD_CStreamWorkspaceBound(params.cParams), - ZSTD_DStreamWorkspaceBound(ZSTD_BTRFS_MAX_INPUT)); - workspace->mem = kvmalloc(workspace->size, GFP_KERNEL); - workspace->buf = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!workspace->mem || !workspace->buf) - goto fail; - - INIT_LIST_HEAD(&workspace->list); - - return &workspace->list; -fail: - zstd_free_workspace(&workspace->list); - return ERR_PTR(-ENOMEM); -} - -static int zstd_compress_pages(struct list_head *ws, - struct address_space *mapping, - u64 start, - struct page **pages, - unsigned long *out_pages, - unsigned long *total_in, - unsigned long *total_out) -{ - struct workspace *workspace = list_entry(ws, struct workspace, list); - ZSTD_CStream *stream; - int ret = 0; - int nr_pages = 0; - struct page *in_page = NULL; /* The current page to read */ - struct page *out_page = NULL; /* The current page to write to */ - ZSTD_inBuffer in_buf = { NULL, 0, 0 }; - ZSTD_outBuffer out_buf = { NULL, 0, 0 }; - unsigned long tot_in = 0; - unsigned long tot_out = 0; - unsigned long len = *total_out; - const unsigned long nr_dest_pages = *out_pages; - unsigned long max_out = nr_dest_pages * PAGE_SIZE; - ZSTD_parameters params = zstd_get_btrfs_parameters(len); - - *out_pages = 0; - *total_out = 0; - *total_in = 0; - - /* Initialize the stream */ - stream = ZSTD_initCStream(params, len, workspace->mem, - workspace->size); - if (!stream) { - pr_warn("BTRFS: ZSTD_initCStream failed\n"); - ret = -EIO; - goto out; - } - - /* map in the first page of input data */ - in_page = find_get_page(mapping, start >> PAGE_SHIFT); - in_buf.src = kmap(in_page); - in_buf.pos = 0; - in_buf.size = min_t(size_t, len, PAGE_SIZE); - - - /* Allocate and map in the output buffer */ - out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); - if (out_page == NULL) { - ret = -ENOMEM; - goto out; - } - pages[nr_pages++] = out_page; - out_buf.dst = kmap(out_page); - out_buf.pos = 0; - out_buf.size = min_t(size_t, max_out, PAGE_SIZE); - - while (1) { - size_t ret2; - - ret2 = ZSTD_compressStream(stream, &out_buf, &in_buf); - if (ZSTD_isError(ret2)) { - pr_debug("BTRFS: ZSTD_compressStream returned %d\n", - ZSTD_getErrorCode(ret2)); - ret = -EIO; - goto out; - } - - /* Check to see if we are making it bigger */ - if (tot_in + in_buf.pos > 8192 && - tot_in + in_buf.pos < - tot_out + out_buf.pos) { - ret = -E2BIG; - goto out; - } - - /* We've reached the end of our output range */ - if (out_buf.pos >= max_out) { - tot_out += out_buf.pos; - ret = -E2BIG; - goto out; - } - - /* Check if we need more output space */ - if (out_buf.pos == out_buf.size) { - tot_out += PAGE_SIZE; - max_out -= PAGE_SIZE; - kunmap(out_page); - if (nr_pages == nr_dest_pages) { - out_page = NULL; - ret = -E2BIG; - goto out; - } - out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); - if (out_page == NULL) { - ret = -ENOMEM; - goto out; - } - pages[nr_pages++] = out_page; - out_buf.dst = kmap(out_page); - out_buf.pos = 0; - out_buf.size = min_t(size_t, max_out, PAGE_SIZE); - } - - /* We've reached the end of the input */ - if (in_buf.pos >= len) { - tot_in += in_buf.pos; - break; - } - - /* Check if we need more input */ - if (in_buf.pos == in_buf.size) { - tot_in += PAGE_SIZE; - kunmap(in_page); - put_page(in_page); - - start += PAGE_SIZE; - len -= PAGE_SIZE; - in_page = find_get_page(mapping, start >> PAGE_SHIFT); - in_buf.src = kmap(in_page); - in_buf.pos = 0; - in_buf.size = min_t(size_t, len, PAGE_SIZE); - } - } - while (1) { - size_t ret2; - - ret2 = ZSTD_endStream(stream, &out_buf); - if (ZSTD_isError(ret2)) { - pr_debug("BTRFS: ZSTD_endStream returned %d\n", - ZSTD_getErrorCode(ret2)); - ret = -EIO; - goto out; - } - if (ret2 == 0) { - tot_out += out_buf.pos; - break; - } - if (out_buf.pos >= max_out) { - tot_out += out_buf.pos; - ret = -E2BIG; - goto out; - } - - tot_out += PAGE_SIZE; - max_out -= PAGE_SIZE; - kunmap(out_page); - if (nr_pages == nr_dest_pages) { - out_page = NULL; - ret = -E2BIG; - goto out; - } - out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); - if (out_page == NULL) { - ret = -ENOMEM; - goto out; - } - pages[nr_pages++] = out_page; - out_buf.dst = kmap(out_page); - out_buf.pos = 0; - out_buf.size = min_t(size_t, max_out, PAGE_SIZE); - } - - if (tot_out >= tot_in) { - ret = -E2BIG; - goto out; - } - - ret = 0; - *total_in = tot_in; - *total_out = tot_out; -out: - *out_pages = nr_pages; - /* Cleanup */ - if (in_page) { - kunmap(in_page); - put_page(in_page); - } - if (out_page) - kunmap(out_page); - return ret; -} - -static int zstd_decompress_bio(struct list_head *ws, struct compressed_bio *cb) -{ - struct workspace *workspace = list_entry(ws, struct workspace, list); - struct page **pages_in = cb->compressed_pages; - u64 disk_start = cb->start; - struct bio *orig_bio = cb->orig_bio; - size_t srclen = cb->compressed_len; - ZSTD_DStream *stream; - int ret = 0; - unsigned long page_in_index = 0; - unsigned long total_pages_in = DIV_ROUND_UP(srclen, PAGE_SIZE); - unsigned long buf_start; - unsigned long total_out = 0; - ZSTD_inBuffer in_buf = { NULL, 0, 0 }; - ZSTD_outBuffer out_buf = { NULL, 0, 0 }; - - stream = ZSTD_initDStream( - ZSTD_BTRFS_MAX_INPUT, workspace->mem, workspace->size); - if (!stream) { - pr_debug("BTRFS: ZSTD_initDStream failed\n"); - ret = -EIO; - goto done; - } - - in_buf.src = kmap(pages_in[page_in_index]); - in_buf.pos = 0; - in_buf.size = min_t(size_t, srclen, PAGE_SIZE); - - out_buf.dst = workspace->buf; - out_buf.pos = 0; - out_buf.size = PAGE_SIZE; - - while (1) { - size_t ret2; - - ret2 = ZSTD_decompressStream(stream, &out_buf, &in_buf); - if (ZSTD_isError(ret2)) { - pr_debug("BTRFS: ZSTD_decompressStream returned %d\n", - ZSTD_getErrorCode(ret2)); - ret = -EIO; - goto done; - } - buf_start = total_out; - total_out += out_buf.pos; - out_buf.pos = 0; - - ret = btrfs_decompress_buf2page(out_buf.dst, buf_start, - total_out, disk_start, orig_bio); - if (ret == 0) - break; - - if (in_buf.pos >= srclen) - break; - - /* Check if we've hit the end of a frame */ - if (ret2 == 0) - break; - - if (in_buf.pos == in_buf.size) { - kunmap(pages_in[page_in_index++]); - if (page_in_index >= total_pages_in) { - in_buf.src = NULL; - ret = -EIO; - goto done; - } - srclen -= PAGE_SIZE; - in_buf.src = kmap(pages_in[page_in_index]); - in_buf.pos = 0; - in_buf.size = min_t(size_t, srclen, PAGE_SIZE); - } - } - ret = 0; - zero_fill_bio(orig_bio); -done: - if (in_buf.src) - kunmap(pages_in[page_in_index]); - return ret; -} - -static int zstd_decompress(struct list_head *ws, unsigned char *data_in, - struct page *dest_page, - unsigned long start_byte, - size_t srclen, size_t destlen) -{ - struct workspace *workspace = list_entry(ws, struct workspace, list); - ZSTD_DStream *stream; - int ret = 0; - size_t ret2; - ZSTD_inBuffer in_buf = { NULL, 0, 0 }; - ZSTD_outBuffer out_buf = { NULL, 0, 0 }; - unsigned long total_out = 0; - unsigned long pg_offset = 0; - char *kaddr; - - stream = ZSTD_initDStream( - ZSTD_BTRFS_MAX_INPUT, workspace->mem, workspace->size); - if (!stream) { - pr_warn("BTRFS: ZSTD_initDStream failed\n"); - ret = -EIO; - goto finish; - } - - destlen = min_t(size_t, destlen, PAGE_SIZE); - - in_buf.src = data_in; - in_buf.pos = 0; - in_buf.size = srclen; - - out_buf.dst = workspace->buf; - out_buf.pos = 0; - out_buf.size = PAGE_SIZE; - - ret2 = 1; - while (pg_offset < destlen && in_buf.pos < in_buf.size) { - unsigned long buf_start; - unsigned long buf_offset; - unsigned long bytes; - - /* Check if the frame is over and we still need more input */ - if (ret2 == 0) { - pr_debug("BTRFS: ZSTD_decompressStream ended early\n"); - ret = -EIO; - goto finish; - } - ret2 = ZSTD_decompressStream(stream, &out_buf, &in_buf); - if (ZSTD_isError(ret2)) { - pr_debug("BTRFS: ZSTD_decompressStream returned %d\n", - ZSTD_getErrorCode(ret2)); - ret = -EIO; - goto finish; - } - - buf_start = total_out; - total_out += out_buf.pos; - out_buf.pos = 0; - - if (total_out <= start_byte) - continue; - - if (total_out > start_byte && buf_start < start_byte) - buf_offset = start_byte - buf_start; - else - buf_offset = 0; - - bytes = min_t(unsigned long, destlen - pg_offset, - out_buf.size - buf_offset); - - kaddr = kmap_atomic(dest_page); - memcpy(kaddr + pg_offset, out_buf.dst + buf_offset, bytes); - kunmap_atomic(kaddr); - - pg_offset += bytes; - } - ret = 0; -finish: - if (pg_offset < destlen) { - kaddr = kmap_atomic(dest_page); - memset(kaddr + pg_offset, 0, destlen - pg_offset); - kunmap_atomic(kaddr); - } - return ret; -} - -const struct btrfs_compress_op btrfs_zstd_compress = { - .alloc_workspace = zstd_alloc_workspace, - .free_workspace = zstd_free_workspace, - .compress_pages = zstd_compress_pages, - .decompress_bio = zstd_decompress_bio, - .decompress = zstd_decompress, -}; |