// SPDX-License-Identifier: GPL-2.0-only/* * drivers/dma-buf/sync_file.c * * Copyright (C) 2012 Google, Inc. */ #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-%lld", 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) goto err; 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 (__dma_fence_is_later(pt_a->seqno, pt_b->seqno, pt_a->ops)) 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_array(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 __poll_t 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) ? EPOLLIN : 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_get_status(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 = compat_ptr_ioctl,};
// SPDX-License-Identifier: GPL-2.0-only
/*
* drivers/dma-buf/sync_file.c
*
* Copyright (C) 2012 Google, Inc.
*/
#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-%lld",
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)
goto err;
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 (__dma_fence_is_later(pt_a->seqno, pt_b->seqno,
pt_a->ops))
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_array(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 __poll_t 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) ? EPOLLIN : 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_get_status(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 = compat_ptr_ioctl,
};