mm-drivers: sync-fence: add sync fence driver snapshot

Add snapshot for syncfence driver in mm-drivers repo.

Change-Id: I43556e3479b45399b1ac0e8ba7a423f36bb21cf9
Signed-off-by: Shashank Babu Chinta Venkata <sbchin@codeaurora.org>
Signed-off-by: Jeykumar Sankaran <quic_jeykumar@quicinc.com>

3 files changed, 535 insertions, 0 deletions

diff --git a/sync_fence/include/uapi/Kbuild b/sync_fence/include/uapi/Kbuild
new file mode 100644
index 0000000..f662bb6
--- /dev/null
+++ b/sync_fence/include/uapi/Kbuild
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note
+
+# Top-level Makefile calls into asm-$(ARCH)
+# List only non-arch directories below
+
+header-y += sync_fence/
diff --git a/sync_fence/include/uapi/sync_fence/qcom_sync_file.h b/sync_fence/include/uapi/sync_fence/qcom_sync_file.h
new file mode 100644
index 0000000..964e0f4
--- /dev/null
+++ b/sync_fence/include/uapi/sync_fence/qcom_sync_file.h
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2021, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _UAPI_LINUX_SPEC_SYNC_H
+#define _UAPI_LINUX_SPEC_SYNC_H
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+
+#define SPEC_FENCE_SIGNAL_ANY 0x1
+#define SPEC_FENCE_SIGNAL_ALL 0x2
+
+/**
+ * struct fence_bind_data - data passed to bind ioctl
+ * @out_bind_fd:	file descriptor of second fence
+ * @fds:	file descriptor list of child fences
+ */
+struct fence_bind_data {
+	__u32	out_bind_fd;
+	__u64	fds;
+};
+
+/**
+ * struct fence_create_data - detailed fence information
+ * @num_fences:	Total fences that array needs to carry.
+ * @flags:	Flags specifying on how to signal the array
+ * @out_bind_fd:	Returns the fence fd.
+ */
+struct fence_create_data {
+	__u32	num_fences;
+	__u32	flags;
+	__u32	out_bind_fd;
+};
+
+#define SPEC_SYNC_MAGIC		'>'
+
+/**
+ * DOC: SPEC_SYNC_IOC_BIND - bind two fences
+ *
+ * Takes a struct fence_bind_data.  binds the child fds with the fence array
+ * pointed by fd1.
+ */
+#define SPEC_SYNC_IOC_BIND	_IOWR(SPEC_SYNC_MAGIC, 3, struct fence_bind_data)
+
+/**
+ * DOC: SPEC_SYNC_IOC_CREATE_FENCE - Create a fence array
+ *
+ * Takes a struct fence_create_data. If num_fences is > 0, fence array will be
+ * created and returns the array fd in fence_create_data.fd1
+ */
+#define SPEC_SYNC_IOC_CREATE_FENCE	_IOWR(SPEC_SYNC_MAGIC, 4, struct fence_create_data)
+
+/**
+ * DOC: SPEC_SYNC_IOC_GET_VER - Get Spec driver version
+ *
+ * Returns Spec driver version.
+ */
+#define SPEC_SYNC_IOC_GET_VER	_IOWR(SPEC_SYNC_MAGIC, 5, __u64)
+
+#endif /* _UAPI_LINUX_SPEC_SYNC_H */
diff --git a/sync_fence/src/qcom_sync_file.c b/sync_fence/src/qcom_sync_file.c
new file mode 100644
index 0000000..3cb2178
--- /dev/null
+++ b/sync_fence/src/qcom_sync_file.c
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2021, The Linux Foundation. All rights reserved.
+ */
+
+#define pr_fmt(fmt)	"%s: " fmt, __func__
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/cdev.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+#include <linux/dma-fence.h>
+#include <linux/dma-fence-array.h>
+#include <linux/sync_file.h>
+#include <uapi/sync_fence/qcom_sync_file.h>
+
+#define CLASS_NAME	"sync"
+#define DRV_NAME	"spec_sync"
+#define DRV_VERSION	1
+#define NAME_LEN	32
+
+#define SPEC_FENCE_FLAG_FENCE_ARRAY 0x10 /* user flags for debug */
+#define FENCE_MIN	1
+#define FENCE_MAX	32
+
+struct sync_device {
+	/* device info */
+	struct class *dev_class;
+	dev_t dev_num;
+	struct device *dev;
+	struct cdev *cdev;
+	struct mutex lock;
+
+	/* device drv data */
+	atomic_t device_available;
+	char name[NAME_LEN];
+	uint32_t version;
+	struct mutex l_lock;
+	struct list_head fence_array_list;
+};
+
+struct fence_array_node {
+	struct dma_fence_array *fence_array;
+	struct list_head list;
+};
+
+/* Speculative Sync Device Driver State */
+static struct sync_device sync_dev;
+
+static bool sanitize_fence_array(struct dma_fence_array *fence)
+{
+	struct fence_array_node *node;
+	int ret = false;
+
+	mutex_lock(&sync_dev.l_lock);
+	list_for_each_entry(node, &sync_dev.fence_array_list, list) {
+		if (node->fence_array == fence) {
+			ret = true;
+			break;
+		}
+	}
+	mutex_unlock(&sync_dev.l_lock);
+
+	return ret;
+}
+
+static void clear_fence_array_tracker(bool force_clear)
+{
+	struct fence_array_node *node, *temp;
+	struct dma_fence_array *array;
+	struct dma_fence *fence;
+	bool is_signaled;
+
+	mutex_lock(&sync_dev.l_lock);
+	list_for_each_entry_safe(node, temp, &sync_dev.fence_array_list, list) {
+		array = node->fence_array;
+		fence = &array->base;
+		is_signaled = dma_fence_is_signaled(fence);
+
+		if (force_clear && !array->fences)
+			array->num_fences = 0;
+
+		pr_debug("force_clear:%d is_signaled:%d pending:%d\n", force_clear, is_signaled,
+			atomic_read(&array->num_pending));
+
+		if (force_clear && !is_signaled && atomic_dec_and_test(&array->num_pending))
+			dma_fence_signal(fence);
+
+		if (force_clear || is_signaled) {
+			dma_fence_put(fence);
+			list_del(&node->list);
+			kfree(node);
+		}
+	}
+	mutex_unlock(&sync_dev.l_lock);
+}
+
+static struct sync_device *spec_fence_init_locked(struct sync_device *obj, const char *name)
+{
+	if (atomic_read(&obj->device_available))
+		return NULL;
+
+	atomic_inc(&obj->device_available);
+
+	memset(obj->name, 0, NAME_LEN);
+	strlcpy(obj->name, name, sizeof(obj->name));
+
+	return obj;
+}
+
+static int spec_sync_open(struct inode *inode, struct file *file)
+{
+	char task_comm[TASK_COMM_LEN];
+	struct sync_device *obj = &sync_dev;
+	int ret = 0;
+
+	if (!inode || !inode->i_cdev || !file) {
+		pr_err("NULL pointer passed\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&sync_dev.lock);
+
+	get_task_comm(task_comm, current);
+
+	obj = spec_fence_init_locked(obj, task_comm);
+	if (!obj) {
+		pr_err("Spec device exists owner:%s caller:%s\n", sync_dev.name, task_comm);
+		ret = -EEXIST;
+		goto end;
+	}
+
+	file->private_data = obj;
+
+end:
+	mutex_unlock(&sync_dev.lock);
+	return ret;
+}
+
+static int spec_sync_release(struct inode *inode, struct file *file)
+{
+	int ret = 0;
+	struct sync_device *obj = file->private_data;
+
+	mutex_lock(&sync_dev.lock);
+
+	if (!atomic_read(&obj->device_available)) {
+		pr_err("sync release failed !!\n");
+		ret = -ENODEV;
+		goto end;
+	}
+
+	clear_fence_array_tracker(true);
+	atomic_dec(&obj->device_available);
+
+end:
+	mutex_unlock(&sync_dev.lock);
+	return ret;
+}
+
+static int spec_sync_ioctl_get_ver(struct sync_device *obj, unsigned long __user arg)
+{
+	uint32_t version = obj->version;
+
+	if (copy_to_user((void __user *)arg, &version, sizeof(uint32_t)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int spec_sync_create_array(struct fence_create_data *f)
+{
+	int fd = get_unused_fd_flags(O_CLOEXEC);
+	struct sync_file *sync_file;
+	struct dma_fence_array *fence_array;
+	struct fence_array_node *node;
+	bool signal_any;
+	int ret = 0;
+
+	if (fd < 0) {
+		pr_err("failed to get_unused_fd_flags\n");
+		return fd;
+	}
+
+	if (f->num_fences < FENCE_MIN || f->num_fences > FENCE_MAX) {
+		pr_err("invalid arguments num_fences:%d\n", f->num_fences);
+		ret = -ERANGE;
+		goto error_args;
+	}
+
+	signal_any = f->flags & SPEC_FENCE_SIGNAL_ALL ? false : true;
+
+	fence_array = dma_fence_array_create(f->num_fences, NULL,
+				dma_fence_context_alloc(1), 0, signal_any);
+
+	/* Set the enable signal such that signalling is not done during wait*/
+	set_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence_array->base.flags);
+	set_bit(SPEC_FENCE_FLAG_FENCE_ARRAY, &fence_array->base.flags);
+
+	sync_file = sync_file_create(&fence_array->base);
+	if (!sync_file) {
+		pr_err("sync_file_create fail\n");
+		ret = -EINVAL;
+		goto err;
+	}
+	node = kzalloc((sizeof(struct fence_array_node)), GFP_KERNEL);
+	if (!node) {
+		fput(sync_file->file);
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	fd_install(fd, sync_file->file);
+	node->fence_array = fence_array;
+
+	mutex_lock(&sync_dev.l_lock);
+	list_add_tail(&node->list, &sync_dev.fence_array_list);
+	mutex_unlock(&sync_dev.l_lock);
+
+	pr_debug("spec fd:%d num_fences:%u\n", fd, f->num_fences);
+	return fd;
+
+err:
+	dma_fence_put(&fence_array->base);
+error_args:
+	put_unused_fd(fd);
+	return ret;
+}
+
+static int spec_sync_ioctl_create_fence(struct sync_device *obj, unsigned long __user arg)
+{
+	struct fence_create_data f;
+	int fd;
+
+	if (copy_from_user(&f, (void __user *)arg, sizeof(f)))
+		return -EFAULT;
+
+	fd = spec_sync_create_array(&f);
+	if (fd < 0)
+		return fd;
+
+	f.out_bind_fd = fd;
+
+	if (copy_to_user((void __user *)arg, &f, sizeof(f)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int spec_sync_bind_array(struct fence_bind_data *sync_bind_info)
+{
+	struct dma_fence_array *fence_array;
+	struct dma_fence *fence = NULL;
+	struct dma_fence *user_fence = NULL;
+	struct dma_fence **fence_list;
+	int *user_fds, ret = 0, i;
+	u32 num_fences, counter;
+
+	fence = sync_file_get_fence(sync_bind_info->out_bind_fd);
+	if (!fence) {
+		pr_err("dma fence failure out_fd:%d\n", sync_bind_info->out_bind_fd);
+		return -EINVAL;
+	}
+
+	fence_array = container_of(fence, struct dma_fence_array, base);
+	if (!sanitize_fence_array(fence_array)) {
+		pr_err("spec fence not found in the registered list out_fd:%d\n",
+				sync_bind_info->out_bind_fd);
+		ret = -EINVAL;
+		goto end;
+	}
+	num_fences = fence_array->num_fences;
+	counter = num_fences;
+
+	user_fds = kzalloc(num_fences * (sizeof(int)), GFP_KERNEL);
+	if (!user_fds) {
+		ret = -ENOMEM;
+		goto end;
+	}
+
+	fence_list = kmalloc_array(num_fences, sizeof(void *), GFP_KERNEL|__GFP_ZERO);
+	if (!fence_list) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	if (copy_from_user(user_fds, (void __user *)sync_bind_info->fds,
+						num_fences * sizeof(int))) {
+		kfree(fence_list);
+		ret = -EFAULT;
+		goto out;
+	}
+
+	fence_array->fences = fence_list;
+	for (i = 0; i < num_fences; i++) {
+		user_fence = sync_file_get_fence(user_fds[i]);
+		if (!user_fence) {
+			pr_err("bind fences are invalid !! user_fd:%d out_bind_fd:%d\n",
+				user_fds[i], sync_bind_info->out_bind_fd);
+			counter = i;
+			ret = -EINVAL;
+			goto bind_invalid;
+		}
+		fence_array->fences[i] = user_fence;
+		pr_debug("spec fd:%d i:%d bind fd:%d error:%d\n", sync_bind_info->out_bind_fd,
+			 i, user_fds[i], fence_array->fences[i]->error);
+	}
+
+	clear_bit(DMA_FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags);
+	dma_fence_enable_sw_signaling(&fence_array->base);
+
+	clear_fence_array_tracker(false);
+
+bind_invalid:
+	if (ret) {
+		for (i = counter - 1; i >= 0; i--)
+			dma_fence_put(fence_array->fences[i]);
+
+		kfree(fence_list);
+		fence_array->fences = NULL;
+		fence_array->num_fences = 0;
+		dma_fence_set_error(fence, -EINVAL);
+		dma_fence_signal(fence);
+		clear_fence_array_tracker(false);
+	}
+out:
+	kfree(user_fds);
+end:
+	dma_fence_put(fence);
+	return ret;
+}
+
+static int spec_sync_ioctl_bind(struct sync_device *obj, unsigned long __user arg)
+{
+	struct fence_bind_data sync_bind_info;
+
+	if (copy_from_user(&sync_bind_info, (void __user *)arg, sizeof(struct fence_bind_data)))
+		return -EFAULT;
+
+	if (sync_bind_info.out_bind_fd < 0) {
+		pr_err("Invalid out_fd:%d\n", sync_bind_info.out_bind_fd);
+		return -EINVAL;
+	}
+
+	return spec_sync_bind_array(&sync_bind_info);
+}
+
+static long spec_sync_ioctl(struct file *file, unsigned int cmd,
+			  unsigned long arg)
+{
+	struct sync_device *obj = file->private_data;
+	int ret = 0;
+
+	switch (cmd) {
+	case SPEC_SYNC_IOC_CREATE_FENCE:
+		ret = spec_sync_ioctl_create_fence(obj, arg);
+		break;
+	case SPEC_SYNC_IOC_BIND:
+		ret = spec_sync_ioctl_bind(obj, arg);
+		break;
+	case SPEC_SYNC_IOC_GET_VER:
+		ret = spec_sync_ioctl_get_ver(obj, arg);
+		break;
+	default:
+		ret = -ENOTTY;
+	}
+
+	return ret;
+}
+
+const struct file_operations spec_sync_fops = {
+	.owner = THIS_MODULE,
+	.open = spec_sync_open,
+	.release = spec_sync_release,
+	.unlocked_ioctl = spec_sync_ioctl,
+};
+
+static int spec_sync_register_device(void)
+{
+	int ret;
+
+	sync_dev.dev_class = class_create(THIS_MODULE, CLASS_NAME);
+	if (sync_dev.dev_class == NULL) {
+		pr_err("%s: class_create fail.\n", __func__);
+		goto res_err;
+	}
+
+	ret = alloc_chrdev_region(&sync_dev.dev_num, 0, 1, DRV_NAME);
+	if (ret) {
+		pr_err("%s: alloc_chrdev_region fail.\n", __func__);
+		goto alloc_chrdev_region_err;
+	}
+
+	sync_dev.dev = device_create(sync_dev.dev_class, NULL,
+					 sync_dev.dev_num,
+					 &sync_dev, DRV_NAME);
+	if (IS_ERR(sync_dev.dev)) {
+		pr_err("%s: device_create fail.\n", __func__);
+		goto device_create_err;
+	}
+
+	sync_dev.cdev = cdev_alloc();
+	if (sync_dev.cdev == NULL) {
+		pr_err("%s: cdev_alloc fail.\n", __func__);
+		goto cdev_alloc_err;
+	}
+	cdev_init(sync_dev.cdev, &spec_sync_fops);
+	sync_dev.cdev->owner = THIS_MODULE;
+
+	ret = cdev_add(sync_dev.cdev, sync_dev.dev_num, 1);
+	if (ret) {
+		pr_err("%s: cdev_add fail.\n", __func__);
+		goto cdev_add_err;
+	}
+
+	sync_dev.version = DRV_VERSION;
+	mutex_init(&sync_dev.lock);
+	mutex_init(&sync_dev.l_lock);
+	INIT_LIST_HEAD(&sync_dev.fence_array_list);
+
+	return 0;
+
+cdev_add_err:
+	cdev_del(sync_dev.cdev);
+cdev_alloc_err:
+	device_destroy(sync_dev.dev_class, sync_dev.dev_num);
+device_create_err:
+	unregister_chrdev_region(sync_dev.dev_num, 1);
+alloc_chrdev_region_err:
+	class_destroy(sync_dev.dev_class);
+res_err:
+	return -ENODEV;
+}
+
+static int __init spec_sync_init(void)
+{
+	int ret = 0;
+
+	ret = spec_sync_register_device();
+	if (ret) {
+		pr_err("%s: speculative sync driver register fail.\n", __func__);
+		return ret;
+	}
+	return ret;
+}
+
+static void __exit spec_sync_deinit(void)
+{
+	cdev_del(sync_dev.cdev);
+	device_destroy(sync_dev.dev_class, sync_dev.dev_num);
+	unregister_chrdev_region(sync_dev.dev_num, 1);
+	class_destroy(sync_dev.dev_class);
+}
+
+module_init(spec_sync_init);
+module_exit(spec_sync_deinit);
+
+MODULE_DESCRIPTION("QCOM Speculative Sync Driver");
+MODULE_LICENSE("GPL v2");