[mirror_ubuntu-bionic-kernel.git] / drivers / dma-buf / sync_file.c

/*
 * drivers/dma-buf/sync_file.c
 *
 * Copyright (C) 2012 Google, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * 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/export.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/poll.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/anon_inodes.h>
#include <linux/sync_file.h>
#include <uapi/linux/sync_file.h>

static const struct file_operations sync_file_fops;

static struct sync_file *sync_file_alloc(void)
{
	struct sync_file *sync_file;

	sync_file = kzalloc(sizeof(*sync_file), GFP_KERNEL);
	if (!sync_file)
		return NULL;

	sync_file->file = anon_inode_getfile("sync_file", &sync_file_fops,
					     sync_file, 0);
	if (IS_ERR(sync_file->file))
		goto err;

	init_waitqueue_head(&sync_file->wq);

	INIT_LIST_HEAD(&sync_file->cb.node);

	return sync_file;

err:
	kfree(sync_file);
	return NULL;
}

static void fence_check_cb_func(struct dma_fence *f, struct dma_fence_cb *cb)
{
	struct sync_file *sync_file;

	sync_file = container_of(cb, struct sync_file, cb);

	wake_up_all(&sync_file->wq);
}

/**
 * sync_file_create() - creates a sync file
 * @fence:	fence to add to the sync_fence
 *
 * Creates a sync_file containg @fence. This function acquires and additional
 * reference of @fence for the newly-created &sync_file, if it succeeds. The
 * sync_file can be released with fput(sync_file->file). Returns the
 * sync_file or NULL in case of error.
 */
struct sync_file *sync_file_create(struct dma_fence *fence)
{
	struct sync_file *sync_file;

	sync_file = sync_file_alloc();
	if (!sync_file)
		return NULL;

	sync_file->fence = dma_fence_get(fence);

	return sync_file;
}
EXPORT_SYMBOL(sync_file_create);

static struct sync_file *sync_file_fdget(int fd)
{
	struct file *file = fget(fd);

	if (!file)
		return NULL;

	if (file->f_op != &sync_file_fops)
		goto err;

	return file->private_data;

err:
	fput(file);
	return NULL;
}

/**
 * sync_file_get_fence - get the fence related to the sync_file fd
 * @fd:		sync_file fd to get the fence from
 *
 * Ensures @fd references a valid sync_file and returns a fence that
 * represents all fence in the sync_file. On error NULL is returned.
 */
struct dma_fence *sync_file_get_fence(int fd)
{
	struct sync_file *sync_file;
	struct dma_fence *fence;

	sync_file = sync_file_fdget(fd);
	if (!sync_file)
		return NULL;

	fence = dma_fence_get(sync_file->fence);
	fput(sync_file->file);

	return fence;
}
EXPORT_SYMBOL(sync_file_get_fence);

/**
 * sync_file_get_name - get the name of the sync_file
 * @sync_file:		sync_file to get the fence from
 * @buf:		destination buffer to copy sync_file name into
 * @len:		available size of destination buffer.
 *
 * Each sync_file may have a name assigned either by the user (when merging
 * sync_files together) or created from the fence it contains. In the latter
 * case construction of the name is deferred until use, and so requires
 * sync_file_get_name().
 *
 * Returns: a string representing the name.
 */
char *sync_file_get_name(struct sync_file *sync_file, char *buf, int len)
{
	if (sync_file->user_name[0]) {
		strlcpy(buf, sync_file->user_name, len);
	} else {
		struct dma_fence *fence = sync_file->fence;

		snprintf(buf, len, "%s-%s%llu-%d",
			 fence->ops->get_driver_name(fence),
			 fence->ops->get_timeline_name(fence),
			 fence->context,
			 fence->seqno);
	}

	return buf;
}

static int sync_file_set_fence(struct sync_file *sync_file,
			       struct dma_fence **fences, int num_fences)
{
	struct dma_fence_array *array;

	/*
	 * The reference for the fences in the new sync_file and held
	 * in add_fence() during the merge procedure, so for num_fences == 1
	 * we already own a new reference to the fence. For num_fence > 1
	 * we own the reference of the dma_fence_array creation.
	 */
	if (num_fences == 1) {
		sync_file->fence = fences[0];
		kfree(fences);
	} else {
		array = dma_fence_array_create(num_fences, fences,
					       dma_fence_context_alloc(1),
					       1, false);
		if (!array)
			return -ENOMEM;

		sync_file->fence = &array->base;
	}

	return 0;
}

static struct dma_fence **get_fences(struct sync_file *sync_file,
				     int *num_fences)
{
	if (dma_fence_is_array(sync_file->fence)) {
		struct dma_fence_array *array = to_dma_fence_array(sync_file->fence);

		*num_fences = array->num_fences;
		return array->fences;
	}

	*num_fences = 1;
	return &sync_file->fence;
}

static void add_fence(struct dma_fence **fences,
		      int *i, struct dma_fence *fence)
{
	fences[*i] = fence;

	if (!dma_fence_is_signaled(fence)) {
		dma_fence_get(fence);
		(*i)++;
	}
}

/**
 * sync_file_merge() - merge two sync_files
 * @name:	name of new fence
 * @a:		sync_file a
 * @b:		sync_file b
 *
 * Creates a new sync_file which contains copies of all the fences in both
 * @a and @b.  @a and @b remain valid, independent sync_file. Returns the
 * new merged sync_file or NULL in case of error.
 */
static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
					 struct sync_file *b)
{
	struct sync_file *sync_file;
	struct dma_fence **fences, **nfences, **a_fences, **b_fences;
	int i, i_a, i_b, num_fences, a_num_fences, b_num_fences;

	sync_file = sync_file_alloc();
	if (!sync_file)
		return NULL;

	a_fences = get_fences(a, &a_num_fences);
	b_fences = get_fences(b, &b_num_fences);
	if (a_num_fences > INT_MAX - b_num_fences)
		return NULL;

	num_fences = a_num_fences + b_num_fences;

	fences = kcalloc(num_fences, sizeof(*fences), GFP_KERNEL);
	if (!fences)
		goto err;

	/*
	 * Assume sync_file a and b are both ordered and have no
	 * duplicates with the same context.
	 *
	 * If a sync_file can only be created with sync_file_merge
	 * and sync_file_create, this is a reasonable assumption.
	 */
	for (i = i_a = i_b = 0; i_a < a_num_fences && i_b < b_num_fences; ) {
		struct dma_fence *pt_a = a_fences[i_a];
		struct dma_fence *pt_b = b_fences[i_b];

		if (pt_a->context < pt_b->context) {
			add_fence(fences, &i, pt_a);

			i_a++;
		} else if (pt_a->context > pt_b->context) {
			add_fence(fences, &i, pt_b);

			i_b++;
		} else {
			if (pt_a->seqno - pt_b->seqno <= INT_MAX)
				add_fence(fences, &i, pt_a);
			else
				add_fence(fences, &i, pt_b);

			i_a++;
			i_b++;
		}
	}

	for (; i_a < a_num_fences; i_a++)
		add_fence(fences, &i, a_fences[i_a]);

	for (; i_b < b_num_fences; i_b++)
		add_fence(fences, &i, b_fences[i_b]);

	if (i == 0)
		fences[i++] = dma_fence_get(a_fences[0]);

	if (num_fences > i) {
		nfences = krealloc(fences, i * sizeof(*fences),
				  GFP_KERNEL);
		if (!nfences)
			goto err;

		fences = nfences;
	}

	if (sync_file_set_fence(sync_file, fences, i) < 0) {
		kfree(fences);
		goto err;
	}

	strlcpy(sync_file->user_name, name, sizeof(sync_file->user_name));
	return sync_file;

err:
	fput(sync_file->file);
	return NULL;

}

static int sync_file_release(struct inode *inode, struct file *file)
{
	struct sync_file *sync_file = file->private_data;

	if (test_bit(POLL_ENABLED, &sync_file->flags))
		dma_fence_remove_callback(sync_file->fence, &sync_file->cb);
	dma_fence_put(sync_file->fence);
	kfree(sync_file);

	return 0;
}

static unsigned int sync_file_poll(struct file *file, poll_table *wait)
{
	struct sync_file *sync_file = file->private_data;

	poll_wait(file, &sync_file->wq, wait);

	if (list_empty(&sync_file->cb.node) &&
	    !test_and_set_bit(POLL_ENABLED, &sync_file->flags)) {
		if (dma_fence_add_callback(sync_file->fence, &sync_file->cb,
					   fence_check_cb_func) < 0)
			wake_up_all(&sync_file->wq);
	}

	return dma_fence_is_signaled(sync_file->fence) ? POLLIN : 0;
}

static long sync_file_ioctl_merge(struct sync_file *sync_file,
				  unsigned long arg)
{
	int fd = get_unused_fd_flags(O_CLOEXEC);
	int err;
	struct sync_file *fence2, *fence3;
	struct sync_merge_data data;

	if (fd < 0)
		return fd;

	if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
		err = -EFAULT;
		goto err_put_fd;
	}

	if (data.flags || data.pad) {
		err = -EINVAL;
		goto err_put_fd;
	}

	fence2 = sync_file_fdget(data.fd2);
	if (!fence2) {
		err = -ENOENT;
		goto err_put_fd;
	}

	data.name[sizeof(data.name) - 1] = '\0';
	fence3 = sync_file_merge(data.name, sync_file, fence2);
	if (!fence3) {
		err = -ENOMEM;
		goto err_put_fence2;
	}

	data.fence = fd;
	if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
		err = -EFAULT;
		goto err_put_fence3;
	}

	fd_install(fd, fence3->file);
	fput(fence2->file);
	return 0;

err_put_fence3:
	fput(fence3->file);

err_put_fence2:
	fput(fence2->file);

err_put_fd:
	put_unused_fd(fd);
	return err;
}

static int sync_fill_fence_info(struct dma_fence *fence,
				 struct sync_fence_info *info)
{
	strlcpy(info->obj_name, fence->ops->get_timeline_name(fence),
		sizeof(info->obj_name));
	strlcpy(info->driver_name, fence->ops->get_driver_name(fence),
		sizeof(info->driver_name));

	info->status = dma_fence_get_status(fence);
	while (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags) &&
	       !test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags))
		cpu_relax();
	info->timestamp_ns =
		test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags) ?
		ktime_to_ns(fence->timestamp) :
		ktime_set(0, 0);

	return info->status;
}

static long sync_file_ioctl_fence_info(struct sync_file *sync_file,
				       unsigned long arg)
{
	struct sync_file_info info;
	struct sync_fence_info *fence_info = NULL;
	struct dma_fence **fences;
	__u32 size;
	int num_fences, ret, i;

	if (copy_from_user(&info, (void __user *)arg, sizeof(info)))
		return -EFAULT;

	if (info.flags || info.pad)
		return -EINVAL;

	fences = get_fences(sync_file, &num_fences);

	/*
	 * Passing num_fences = 0 means that userspace doesn't want to
	 * retrieve any sync_fence_info. If num_fences = 0 we skip filling
	 * sync_fence_info and return the actual number of fences on
	 * info->num_fences.
	 */
	if (!info.num_fences) {
		info.status = dma_fence_is_signaled(sync_file->fence);
		goto no_fences;
	} else {
		info.status = 1;
	}

	if (info.num_fences < num_fences)
		return -EINVAL;

	size = num_fences * sizeof(*fence_info);
	fence_info = kzalloc(size, GFP_KERNEL);
	if (!fence_info)
		return -ENOMEM;

	for (i = 0; i < num_fences; i++) {
		int status = sync_fill_fence_info(fences[i], &fence_info[i]);
		info.status = info.status <= 0 ? info.status : status;
	}

	if (copy_to_user(u64_to_user_ptr(info.sync_fence_info), fence_info,
			 size)) {
		ret = -EFAULT;
		goto out;
	}

no_fences:
	sync_file_get_name(sync_file, info.name, sizeof(info.name));
	info.num_fences = num_fences;

	if (copy_to_user((void __user *)arg, &info, sizeof(info)))
		ret = -EFAULT;
	else
		ret = 0;

out:
	kfree(fence_info);

	return ret;
}

static long sync_file_ioctl(struct file *file, unsigned int cmd,
			    unsigned long arg)
{
	struct sync_file *sync_file = file->private_data;

	switch (cmd) {
	case SYNC_IOC_MERGE:
		return sync_file_ioctl_merge(sync_file, arg);

	case SYNC_IOC_FILE_INFO:
		return sync_file_ioctl_fence_info(sync_file, arg);

	default:
		return -ENOTTY;
	}
}

static const struct file_operations sync_file_fops = {
	.release = sync_file_release,
	.poll = sync_file_poll,
	.unlocked_ioctl = sync_file_ioctl,
	.compat_ioctl = sync_file_ioctl,
};
Commit	Line	Data
d4cab38e GP	1	/*
	2	* drivers/dma-buf/sync_file.c
	3	*
	4	* Copyright (C) 2012 Google, Inc.
	5	*
	6	* This software is licensed under the terms of the GNU General Public
	7	* License version 2, as published by the Free Software Foundation, and
	8	* may be copied, distributed, and modified under those terms.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	*/
	16
	17	#include <linux/export.h>
	18	#include <linux/file.h>
	19	#include <linux/fs.h>
	20	#include <linux/kernel.h>
	21	#include <linux/poll.h>
	22	#include <linux/sched.h>
	23	#include <linux/slab.h>
	24	#include <linux/uaccess.h>
	25	#include <linux/anon_inodes.h>
460bfc41 GP	26	#include <linux/sync_file.h>
460bfc41 GP	27	#include <uapi/linux/sync_file.h>
d4cab38e GP	28
	29	static const struct file_operations sync_file_fops;
	30
a02b9dc9	31	static struct sync_file *sync_file_alloc(void)
d4cab38e GP	32	{
	33	struct sync_file *sync_file;
	34
a02b9dc9	35	sync_file = kzalloc(sizeof(*sync_file), GFP_KERNEL);
d4cab38e GP	36	if (!sync_file)
	37	return NULL;
	38
	39	sync_file->file = anon_inode_getfile("sync_file", &sync_file_fops,
	40	sync_file, 0);
	41	if (IS_ERR(sync_file->file))
	42	goto err;
	43
d4cab38e GP	44	init_waitqueue_head(&sync_file->wq);
d4cab38e GP	45
a02b9dc9 GP	46	INIT_LIST_HEAD(&sync_file->cb.node);
a02b9dc9 GP	47
d4cab38e GP	48	return sync_file;
	49
	50	err:
	51	kfree(sync_file);
	52	return NULL;
	53	}
	54
f54d1867	55	static void fence_check_cb_func(struct dma_fence f, struct dma_fence_cb cb)
d4cab38e	56	{
d4cab38e GP	57	struct sync_file *sync_file;
d4cab38e GP	58
a02b9dc9	59	sync_file = container_of(cb, struct sync_file, cb);
d4cab38e	60
a02b9dc9	61	wake_up_all(&sync_file->wq);
d4cab38e GP	62	}
	63
	64	/**
c240a714	65	* sync_file_create() - creates a sync file
d4cab38e GP	66	* @fence: fence to add to the sync_fence
d4cab38e GP	67	*
24a36734 DV	68	* Creates a sync_file containg @fence. This function acquires and additional
	69	* reference of @fence for the newly-created &sync_file, if it succeeds. The
	70	* sync_file can be released with fput(sync_file->file). Returns the
	71	* sync_file or NULL in case of error.
d4cab38e	72	*/
f54d1867	73	struct sync_file sync_file_create(struct dma_fence fence)
d4cab38e GP	74	{
	75	struct sync_file *sync_file;
	76
a02b9dc9	77	sync_file = sync_file_alloc();
d4cab38e GP	78	if (!sync_file)
	79	return NULL;
	80
f54d1867	81	sync_file->fence = dma_fence_get(fence);
a02b9dc9	82
d4cab38e GP	83	return sync_file;
	84	}
	85	EXPORT_SYMBOL(sync_file_create);
	86
d4cab38e GP	87	static struct sync_file *sync_file_fdget(int fd)
	88	{
	89	struct file *file = fget(fd);
	90
	91	if (!file)
	92	return NULL;
	93
	94	if (file->f_op != &sync_file_fops)
	95	goto err;
	96
	97	return file->private_data;
	98
	99	err:
	100	fput(file);
	101	return NULL;
	102	}
	103
972526a4 GP	104	/**
	105	* sync_file_get_fence - get the fence related to the sync_file fd
	106	* @fd: sync_file fd to get the fence from
	107	*
	108	* Ensures @fd references a valid sync_file and returns a fence that
	109	* represents all fence in the sync_file. On error NULL is returned.
	110	*/
f54d1867	111	struct dma_fence *sync_file_get_fence(int fd)
972526a4 GP	112	{
972526a4 GP	113	struct sync_file *sync_file;
f54d1867	114	struct dma_fence *fence;
972526a4 GP	115
	116	sync_file = sync_file_fdget(fd);
	117	if (!sync_file)
	118	return NULL;
	119
f54d1867	120	fence = dma_fence_get(sync_file->fence);
972526a4 GP	121	fput(sync_file->file);
	122
	123	return fence;
	124	}
	125	EXPORT_SYMBOL(sync_file_get_fence);
	126
71ebc9a3 CW	127	/**
	128	* sync_file_get_name - get the name of the sync_file
	129	* @sync_file: sync_file to get the fence from
	130	* @buf: destination buffer to copy sync_file name into
	131	* @len: available size of destination buffer.
	132	*
	133	* Each sync_file may have a name assigned either by the user (when merging
	134	* sync_files together) or created from the fence it contains. In the latter
	135	* case construction of the name is deferred until use, and so requires
	136	* sync_file_get_name().
	137	*
	138	* Returns: a string representing the name.
	139	*/
	140	char sync_file_get_name(struct sync_file sync_file, char *buf, int len)
	141	{
	142	if (sync_file->user_name[0]) {
	143	strlcpy(buf, sync_file->user_name, len);
	144	} else {
	145	struct dma_fence *fence = sync_file->fence;
	146
	147	snprintf(buf, len, "%s-%s%llu-%d",
	148	fence->ops->get_driver_name(fence),
	149	fence->ops->get_timeline_name(fence),
	150	fence->context,
	151	fence->seqno);
	152	}
	153
	154	return buf;
	155	}
	156
a02b9dc9	157	static int sync_file_set_fence(struct sync_file *sync_file,
f54d1867	158	struct dma_fence **fences, int num_fences)
d4cab38e	159	{
f54d1867	160	struct dma_fence_array *array;
a02b9dc9 GP	161
	162	/*
	163	* The reference for the fences in the new sync_file and held
	164	* in add_fence() during the merge procedure, so for num_fences == 1
	165	* we already own a new reference to the fence. For num_fence > 1
f54d1867	166	* we own the reference of the dma_fence_array creation.
a02b9dc9 GP	167	*/
	168	if (num_fences == 1) {
	169	sync_file->fence = fences[0];
c654dd07	170	kfree(fences);
a02b9dc9	171	} else {
f54d1867 CW	172	array = dma_fence_array_create(num_fences, fences,
	173	dma_fence_context_alloc(1),
	174	1, false);
a02b9dc9 GP	175	if (!array)
	176	return -ENOMEM;
	177
	178	sync_file->fence = &array->base;
	179	}
d4cab38e	180
a02b9dc9 GP	181	return 0;
	182	}
	183
f54d1867 CW	184	static struct dma_fence *get_fences(struct sync_file sync_file,
f54d1867 CW	185	int *num_fences)
a02b9dc9	186	{
f54d1867 CW	187	if (dma_fence_is_array(sync_file->fence)) {
f54d1867 CW	188	struct dma_fence_array *array = to_dma_fence_array(sync_file->fence);
a02b9dc9 GP	189
	190	*num_fences = array->num_fences;
	191	return array->fences;
	192	}
	193
	194	*num_fences = 1;
	195	return &sync_file->fence;
	196	}
	197
f54d1867 CW	198	static void add_fence(struct dma_fence **fences,
f54d1867 CW	199	int i, struct dma_fence fence)
a02b9dc9 GP	200	{
	201	fences[*i] = fence;
	202
f54d1867 CW	203	if (!dma_fence_is_signaled(fence)) {
f54d1867 CW	204	dma_fence_get(fence);
d4cab38e GP	205	(*i)++;
	206	}
	207	}
	208
	209	/**
	210	* sync_file_merge() - merge two sync_files
	211	* @name: name of new fence
	212	* @a: sync_file a
	213	* @b: sync_file b
	214	*
	215	* Creates a new sync_file which contains copies of all the fences in both
	216	* @a and @b. @a and @b remain valid, independent sync_file. Returns the
	217	* new merged sync_file or NULL in case of error.
	218	*/
	219	static struct sync_file sync_file_merge(const char name, struct sync_file *a,
	220	struct sync_file *b)
	221	{
d4cab38e	222	struct sync_file *sync_file;
f54d1867	223	struct dma_fence fences, nfences, a_fences, b_fences;
a02b9dc9	224	int i, i_a, i_b, num_fences, a_num_fences, b_num_fences;
d4cab38e	225
a02b9dc9	226	sync_file = sync_file_alloc();
d4cab38e GP	227	if (!sync_file)
	228	return NULL;
	229
a02b9dc9 GP	230	a_fences = get_fences(a, &a_num_fences);
	231	b_fences = get_fences(b, &b_num_fences);
	232	if (a_num_fences > INT_MAX - b_num_fences)
	233	return NULL;
	234
	235	num_fences = a_num_fences + b_num_fences;
	236
	237	fences = kcalloc(num_fences, sizeof(*fences), GFP_KERNEL);
	238	if (!fences)
	239	goto err;
d4cab38e GP	240
	241	/*
	242	* Assume sync_file a and b are both ordered and have no
	243	* duplicates with the same context.
	244	*
	245	* If a sync_file can only be created with sync_file_merge
	246	* and sync_file_create, this is a reasonable assumption.
	247	*/
a02b9dc9	248	for (i = i_a = i_b = 0; i_a < a_num_fences && i_b < b_num_fences; ) {
f54d1867 CW	249	struct dma_fence *pt_a = a_fences[i_a];
f54d1867 CW	250	struct dma_fence *pt_b = b_fences[i_b];
d4cab38e GP	251
d4cab38e GP	252	if (pt_a->context < pt_b->context) {
a02b9dc9	253	add_fence(fences, &i, pt_a);
d4cab38e GP	254
	255	i_a++;
	256	} else if (pt_a->context > pt_b->context) {
a02b9dc9	257	add_fence(fences, &i, pt_b);
d4cab38e GP	258
	259	i_b++;
	260	} else {
	261	if (pt_a->seqno - pt_b->seqno <= INT_MAX)
a02b9dc9	262	add_fence(fences, &i, pt_a);
d4cab38e	263	else
a02b9dc9	264	add_fence(fences, &i, pt_b);
d4cab38e GP	265
	266	i_a++;
	267	i_b++;
	268	}
	269	}
	270
a02b9dc9 GP	271	for (; i_a < a_num_fences; i_a++)
	272	add_fence(fences, &i, a_fences[i_a]);
	273
	274	for (; i_b < b_num_fences; i_b++)
	275	add_fence(fences, &i, b_fences[i_b]);
	276
7cec540a	277	if (i == 0)
f54d1867	278	fences[i++] = dma_fence_get(a_fences[0]);
d4cab38e	279
a02b9dc9 GP	280	if (num_fences > i) {
	281	nfences = krealloc(fences, i * sizeof(*fences),
	282	GFP_KERNEL);
	283	if (!nfences)
	284	goto err;
	285
	286	fences = nfences;
	287	}
	288
	289	if (sync_file_set_fence(sync_file, fences, i) < 0) {
	290	kfree(fences);
	291	goto err;
	292	}
d4cab38e	293
71ebc9a3	294	strlcpy(sync_file->user_name, name, sizeof(sync_file->user_name));
d4cab38e	295	return sync_file;
a02b9dc9 GP	296
	297	err:
	298	fput(sync_file->file);
	299	return NULL;
	300
d4cab38e GP	301	}
d4cab38e GP	302
d8f2ebaa	303	static int sync_file_release(struct inode inode, struct file file)
d4cab38e	304	{
d8f2ebaa	305	struct sync_file *sync_file = file->private_data;
d4cab38e	306
99f82843	307	if (test_bit(POLL_ENABLED, &sync_file->flags))
f54d1867 CW	308	dma_fence_remove_callback(sync_file->fence, &sync_file->cb);
f54d1867 CW	309	dma_fence_put(sync_file->fence);
d4cab38e	310	kfree(sync_file);
d4cab38e	311
d4cab38e GP	312	return 0;
	313	}
	314
	315	static unsigned int sync_file_poll(struct file file, poll_table wait)
	316	{
	317	struct sync_file *sync_file = file->private_data;
d4cab38e GP	318
	319	poll_wait(file, &sync_file->wq, wait);
	320
99f82843 CW	321	if (list_empty(&sync_file->cb.node) &&
99f82843 CW	322	!test_and_set_bit(POLL_ENABLED, &sync_file->flags)) {
f54d1867 CW	323	if (dma_fence_add_callback(sync_file->fence, &sync_file->cb,
f54d1867 CW	324	fence_check_cb_func) < 0)
e2416553 GP	325	wake_up_all(&sync_file->wq);
e2416553 GP	326	}
d4cab38e	327
f54d1867	328	return dma_fence_is_signaled(sync_file->fence) ? POLLIN : 0;
d4cab38e GP	329	}
	330
	331	static long sync_file_ioctl_merge(struct sync_file *sync_file,
92e06213	332	unsigned long arg)
d4cab38e GP	333	{
	334	int fd = get_unused_fd_flags(O_CLOEXEC);
	335	int err;
	336	struct sync_file fence2, fence3;
	337	struct sync_merge_data data;
	338
	339	if (fd < 0)
	340	return fd;
	341
	342	if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
	343	err = -EFAULT;
	344	goto err_put_fd;
	345	}
	346
	347	if (data.flags \|\| data.pad) {
	348	err = -EINVAL;
	349	goto err_put_fd;
	350	}
	351
	352	fence2 = sync_file_fdget(data.fd2);
	353	if (!fence2) {
	354	err = -ENOENT;
	355	goto err_put_fd;
	356	}
	357
	358	data.name[sizeof(data.name) - 1] = '\0';
	359	fence3 = sync_file_merge(data.name, sync_file, fence2);
	360	if (!fence3) {
	361	err = -ENOMEM;
	362	goto err_put_fence2;
	363	}
	364
	365	data.fence = fd;
	366	if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
	367	err = -EFAULT;
	368	goto err_put_fence3;
	369	}
	370
	371	fd_install(fd, fence3->file);
	372	fput(fence2->file);
	373	return 0;
	374
	375	err_put_fence3:
	376	fput(fence3->file);
	377
	378	err_put_fence2:
	379	fput(fence2->file);
	380
	381	err_put_fd:
	382	put_unused_fd(fd);
	383	return err;
	384	}
	385
f7974880	386	static int sync_fill_fence_info(struct dma_fence *fence,
92e06213	387	struct sync_fence_info *info)
d4cab38e GP	388	{
	389	strlcpy(info->obj_name, fence->ops->get_timeline_name(fence),
	390	sizeof(info->obj_name));
	391	strlcpy(info->driver_name, fence->ops->get_driver_name(fence),
	392	sizeof(info->driver_name));
d6c99f4b CW	393
d6c99f4b CW	394	info->status = dma_fence_get_status(fence);
76250f2b CW	395	while (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags) &&
	396	!test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags))
	397	cpu_relax();
	398	info->timestamp_ns =
	399	test_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags) ?
	400	ktime_to_ns(fence->timestamp) :
	401	ktime_set(0, 0);
f7974880 JER	402
f7974880 JER	403	return info->status;
d4cab38e GP	404	}
	405
	406	static long sync_file_ioctl_fence_info(struct sync_file *sync_file,
92e06213	407	unsigned long arg)
d4cab38e GP	408	{
	409	struct sync_file_info info;
	410	struct sync_fence_info *fence_info = NULL;
f54d1867	411	struct dma_fence **fences;
d4cab38e	412	__u32 size;
a02b9dc9	413	int num_fences, ret, i;
d4cab38e GP	414
	415	if (copy_from_user(&info, (void __user *)arg, sizeof(info)))
	416	return -EFAULT;
	417
	418	if (info.flags \|\| info.pad)
	419	return -EINVAL;
	420
a02b9dc9 GP	421	fences = get_fences(sync_file, &num_fences);
a02b9dc9 GP	422
d4cab38e GP	423	/*
	424	* Passing num_fences = 0 means that userspace doesn't want to
	425	* retrieve any sync_fence_info. If num_fences = 0 we skip filling
	426	* sync_fence_info and return the actual number of fences on
	427	* info->num_fences.
	428	*/
f7974880 JER	429	if (!info.num_fences) {
f7974880 JER	430	info.status = dma_fence_is_signaled(sync_file->fence);
d4cab38e	431	goto no_fences;
f7974880 JER	432	} else {
	433	info.status = 1;
	434	}
d4cab38e	435
a02b9dc9	436	if (info.num_fences < num_fences)
d4cab38e GP	437	return -EINVAL;
d4cab38e GP	438
a02b9dc9	439	size = num_fences * sizeof(*fence_info);
d4cab38e GP	440	fence_info = kzalloc(size, GFP_KERNEL);
	441	if (!fence_info)
	442	return -ENOMEM;
	443
f7974880 JER	444	for (i = 0; i < num_fences; i++) {
	445	int status = sync_fill_fence_info(fences[i], &fence_info[i]);
	446	info.status = info.status <= 0 ? info.status : status;
	447	}
d4cab38e GP	448
	449	if (copy_to_user(u64_to_user_ptr(info.sync_fence_info), fence_info,
	450	size)) {
	451	ret = -EFAULT;
	452	goto out;
	453	}
	454
	455	no_fences:
71ebc9a3	456	sync_file_get_name(sync_file, info.name, sizeof(info.name));
a02b9dc9	457	info.num_fences = num_fences;
d4cab38e GP	458
	459	if (copy_to_user((void __user *)arg, &info, sizeof(info)))
	460	ret = -EFAULT;
	461	else
	462	ret = 0;
	463
	464	out:
	465	kfree(fence_info);
	466
	467	return ret;
	468	}
	469
	470	static long sync_file_ioctl(struct file *file, unsigned int cmd,
92e06213	471	unsigned long arg)
d4cab38e GP	472	{
	473	struct sync_file *sync_file = file->private_data;
	474
	475	switch (cmd) {
	476	case SYNC_IOC_MERGE:
	477	return sync_file_ioctl_merge(sync_file, arg);
	478
	479	case SYNC_IOC_FILE_INFO:
	480	return sync_file_ioctl_fence_info(sync_file, arg);
	481
	482	default:
	483	return -ENOTTY;
	484	}
	485	}
	486
	487	static const struct file_operations sync_file_fops = {
	488	.release = sync_file_release,
	489	.poll = sync_file_poll,
	490	.unlocked_ioctl = sync_file_ioctl,
	491	.compat_ioctl = sync_file_ioctl,
	492	};