blob: b29a9e817320a844ce0a0f8a89711266a17211a0 [file] [log] [blame]
Gustavo Padovand4cab382016-04-28 10:46:54 -03001/*
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>
Gustavo Padovan460bfc42016-04-28 10:46:57 -030026#include <linux/sync_file.h>
27#include <uapi/linux/sync_file.h>
Gustavo Padovand4cab382016-04-28 10:46:54 -030028
29static const struct file_operations sync_file_fops;
30
Gustavo Padovana02b9dc2016-08-05 10:39:35 -030031static struct sync_file *sync_file_alloc(void)
Gustavo Padovand4cab382016-04-28 10:46:54 -030032{
33 struct sync_file *sync_file;
34
Gustavo Padovana02b9dc2016-08-05 10:39:35 -030035 sync_file = kzalloc(sizeof(*sync_file), GFP_KERNEL);
Gustavo Padovand4cab382016-04-28 10:46:54 -030036 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
44 kref_init(&sync_file->kref);
45
46 init_waitqueue_head(&sync_file->wq);
47
Gustavo Padovana02b9dc2016-08-05 10:39:35 -030048 INIT_LIST_HEAD(&sync_file->cb.node);
49
Gustavo Padovand4cab382016-04-28 10:46:54 -030050 return sync_file;
51
52err:
53 kfree(sync_file);
54 return NULL;
55}
56
57static void fence_check_cb_func(struct fence *f, struct fence_cb *cb)
58{
Gustavo Padovand4cab382016-04-28 10:46:54 -030059 struct sync_file *sync_file;
60
Gustavo Padovana02b9dc2016-08-05 10:39:35 -030061 sync_file = container_of(cb, struct sync_file, cb);
Gustavo Padovand4cab382016-04-28 10:46:54 -030062
Gustavo Padovana02b9dc2016-08-05 10:39:35 -030063 wake_up_all(&sync_file->wq);
Gustavo Padovand4cab382016-04-28 10:46:54 -030064}
65
66/**
Gustavo Padovanc240a712016-04-28 10:46:55 -030067 * sync_file_create() - creates a sync file
Gustavo Padovand4cab382016-04-28 10:46:54 -030068 * @fence: fence to add to the sync_fence
69 *
70 * Creates a sync_file containg @fence. Once this is called, the sync_file
Gustavo Padovanc240a712016-04-28 10:46:55 -030071 * takes ownership of @fence. The sync_file can be released with
72 * fput(sync_file->file). Returns the sync_file or NULL in case of error.
Gustavo Padovand4cab382016-04-28 10:46:54 -030073 */
74struct sync_file *sync_file_create(struct fence *fence)
75{
76 struct sync_file *sync_file;
77
Gustavo Padovana02b9dc2016-08-05 10:39:35 -030078 sync_file = sync_file_alloc();
Gustavo Padovand4cab382016-04-28 10:46:54 -030079 if (!sync_file)
80 return NULL;
81
Gustavo Padovana02b9dc2016-08-05 10:39:35 -030082 sync_file->fence = fence;
83
Gustavo Padovan041916a2016-06-03 12:46:31 -030084 snprintf(sync_file->name, sizeof(sync_file->name), "%s-%s%llu-%d",
Gustavo Padovand4cab382016-04-28 10:46:54 -030085 fence->ops->get_driver_name(fence),
86 fence->ops->get_timeline_name(fence), fence->context,
87 fence->seqno);
88
Gustavo Padovand4cab382016-04-28 10:46:54 -030089 return sync_file;
90}
91EXPORT_SYMBOL(sync_file_create);
92
93/**
94 * sync_file_fdget() - get a sync_file from an fd
95 * @fd: fd referencing a fence
96 *
97 * Ensures @fd references a valid sync_file, increments the refcount of the
98 * backing file. Returns the sync_file or NULL in case of error.
99 */
100static struct sync_file *sync_file_fdget(int fd)
101{
102 struct file *file = fget(fd);
103
104 if (!file)
105 return NULL;
106
107 if (file->f_op != &sync_file_fops)
108 goto err;
109
110 return file->private_data;
111
112err:
113 fput(file);
114 return NULL;
115}
116
Gustavo Padovan972526a2016-08-05 10:39:36 -0300117/**
118 * sync_file_get_fence - get the fence related to the sync_file fd
119 * @fd: sync_file fd to get the fence from
120 *
121 * Ensures @fd references a valid sync_file and returns a fence that
122 * represents all fence in the sync_file. On error NULL is returned.
123 */
124struct fence *sync_file_get_fence(int fd)
125{
126 struct sync_file *sync_file;
127 struct fence *fence;
128
129 sync_file = sync_file_fdget(fd);
130 if (!sync_file)
131 return NULL;
132
133 fence = fence_get(sync_file->fence);
134 fput(sync_file->file);
135
136 return fence;
137}
138EXPORT_SYMBOL(sync_file_get_fence);
139
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300140static int sync_file_set_fence(struct sync_file *sync_file,
141 struct fence **fences, int num_fences)
Gustavo Padovand4cab382016-04-28 10:46:54 -0300142{
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300143 struct fence_array *array;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300144
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300145 /*
146 * The reference for the fences in the new sync_file and held
147 * in add_fence() during the merge procedure, so for num_fences == 1
148 * we already own a new reference to the fence. For num_fence > 1
149 * we own the reference of the fence_array creation.
150 */
151 if (num_fences == 1) {
152 sync_file->fence = fences[0];
Gustavo Padovanc654dd02016-09-21 10:20:19 +0300153 kfree(fences);
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300154 } else {
155 array = fence_array_create(num_fences, fences,
156 fence_context_alloc(1), 1, false);
157 if (!array)
158 return -ENOMEM;
159
160 sync_file->fence = &array->base;
161 }
162
163 return 0;
164}
165
166static struct fence **get_fences(struct sync_file *sync_file, int *num_fences)
167{
168 if (fence_is_array(sync_file->fence)) {
169 struct fence_array *array = to_fence_array(sync_file->fence);
170
171 *num_fences = array->num_fences;
172 return array->fences;
173 }
174
175 *num_fences = 1;
176 return &sync_file->fence;
177}
178
179static void add_fence(struct fence **fences, int *i, struct fence *fence)
180{
181 fences[*i] = fence;
182
183 if (!fence_is_signaled(fence)) {
Gustavo Padovand4cab382016-04-28 10:46:54 -0300184 fence_get(fence);
185 (*i)++;
186 }
187}
188
189/**
190 * sync_file_merge() - merge two sync_files
191 * @name: name of new fence
192 * @a: sync_file a
193 * @b: sync_file b
194 *
195 * Creates a new sync_file which contains copies of all the fences in both
196 * @a and @b. @a and @b remain valid, independent sync_file. Returns the
197 * new merged sync_file or NULL in case of error.
198 */
199static struct sync_file *sync_file_merge(const char *name, struct sync_file *a,
200 struct sync_file *b)
201{
Gustavo Padovand4cab382016-04-28 10:46:54 -0300202 struct sync_file *sync_file;
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300203 struct fence **fences, **nfences, **a_fences, **b_fences;
204 int i, i_a, i_b, num_fences, a_num_fences, b_num_fences;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300205
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300206 sync_file = sync_file_alloc();
Gustavo Padovand4cab382016-04-28 10:46:54 -0300207 if (!sync_file)
208 return NULL;
209
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300210 a_fences = get_fences(a, &a_num_fences);
211 b_fences = get_fences(b, &b_num_fences);
212 if (a_num_fences > INT_MAX - b_num_fences)
213 return NULL;
214
215 num_fences = a_num_fences + b_num_fences;
216
217 fences = kcalloc(num_fences, sizeof(*fences), GFP_KERNEL);
218 if (!fences)
219 goto err;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300220
221 /*
222 * Assume sync_file a and b are both ordered and have no
223 * duplicates with the same context.
224 *
225 * If a sync_file can only be created with sync_file_merge
226 * and sync_file_create, this is a reasonable assumption.
227 */
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300228 for (i = i_a = i_b = 0; i_a < a_num_fences && i_b < b_num_fences; ) {
229 struct fence *pt_a = a_fences[i_a];
230 struct fence *pt_b = b_fences[i_b];
Gustavo Padovand4cab382016-04-28 10:46:54 -0300231
232 if (pt_a->context < pt_b->context) {
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300233 add_fence(fences, &i, pt_a);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300234
235 i_a++;
236 } else if (pt_a->context > pt_b->context) {
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300237 add_fence(fences, &i, pt_b);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300238
239 i_b++;
240 } else {
241 if (pt_a->seqno - pt_b->seqno <= INT_MAX)
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300242 add_fence(fences, &i, pt_a);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300243 else
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300244 add_fence(fences, &i, pt_b);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300245
246 i_a++;
247 i_b++;
248 }
249 }
250
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300251 for (; i_a < a_num_fences; i_a++)
252 add_fence(fences, &i, a_fences[i_a]);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300253
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300254 for (; i_b < b_num_fences; i_b++)
255 add_fence(fences, &i, b_fences[i_b]);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300256
Rafael Antognolli7cec5402016-09-15 12:14:25 -0700257 if (i == 0)
258 fences[i++] = fence_get(a_fences[0]);
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300259
260 if (num_fences > i) {
261 nfences = krealloc(fences, i * sizeof(*fences),
262 GFP_KERNEL);
263 if (!nfences)
264 goto err;
265
266 fences = nfences;
267 }
268
269 if (sync_file_set_fence(sync_file, fences, i) < 0) {
270 kfree(fences);
271 goto err;
272 }
273
Gustavo Padovand4cab382016-04-28 10:46:54 -0300274 strlcpy(sync_file->name, name, sizeof(sync_file->name));
275 return sync_file;
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300276
277err:
278 fput(sync_file->file);
279 return NULL;
280
Gustavo Padovand4cab382016-04-28 10:46:54 -0300281}
282
283static void sync_file_free(struct kref *kref)
284{
285 struct sync_file *sync_file = container_of(kref, struct sync_file,
286 kref);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300287
Gustavo Padovane2416552016-08-05 10:39:38 -0300288 if (test_bit(POLL_ENABLED, &sync_file->fence->flags))
289 fence_remove_callback(sync_file->fence, &sync_file->cb);
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300290 fence_put(sync_file->fence);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300291 kfree(sync_file);
292}
293
294static int sync_file_release(struct inode *inode, struct file *file)
295{
296 struct sync_file *sync_file = file->private_data;
297
298 kref_put(&sync_file->kref, sync_file_free);
299 return 0;
300}
301
302static unsigned int sync_file_poll(struct file *file, poll_table *wait)
303{
304 struct sync_file *sync_file = file->private_data;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300305
306 poll_wait(file, &sync_file->wq, wait);
307
Chris Wilsonecebca72016-08-29 19:16:13 +0100308 if (!poll_does_not_wait(wait) &&
309 !test_and_set_bit(POLL_ENABLED, &sync_file->fence->flags)) {
Gustavo Padovane2416552016-08-05 10:39:38 -0300310 if (fence_add_callback(sync_file->fence, &sync_file->cb,
311 fence_check_cb_func) < 0)
312 wake_up_all(&sync_file->wq);
313 }
Gustavo Padovand4cab382016-04-28 10:46:54 -0300314
Gustavo Padovane2416552016-08-05 10:39:38 -0300315 return fence_is_signaled(sync_file->fence) ? POLLIN : 0;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300316}
317
318static long sync_file_ioctl_merge(struct sync_file *sync_file,
Gustavo Padovan92e06212016-04-28 10:46:56 -0300319 unsigned long arg)
Gustavo Padovand4cab382016-04-28 10:46:54 -0300320{
321 int fd = get_unused_fd_flags(O_CLOEXEC);
322 int err;
323 struct sync_file *fence2, *fence3;
324 struct sync_merge_data data;
325
326 if (fd < 0)
327 return fd;
328
329 if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
330 err = -EFAULT;
331 goto err_put_fd;
332 }
333
334 if (data.flags || data.pad) {
335 err = -EINVAL;
336 goto err_put_fd;
337 }
338
339 fence2 = sync_file_fdget(data.fd2);
340 if (!fence2) {
341 err = -ENOENT;
342 goto err_put_fd;
343 }
344
345 data.name[sizeof(data.name) - 1] = '\0';
346 fence3 = sync_file_merge(data.name, sync_file, fence2);
347 if (!fence3) {
348 err = -ENOMEM;
349 goto err_put_fence2;
350 }
351
352 data.fence = fd;
353 if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
354 err = -EFAULT;
355 goto err_put_fence3;
356 }
357
358 fd_install(fd, fence3->file);
359 fput(fence2->file);
360 return 0;
361
362err_put_fence3:
363 fput(fence3->file);
364
365err_put_fence2:
366 fput(fence2->file);
367
368err_put_fd:
369 put_unused_fd(fd);
370 return err;
371}
372
373static void sync_fill_fence_info(struct fence *fence,
Gustavo Padovan92e06212016-04-28 10:46:56 -0300374 struct sync_fence_info *info)
Gustavo Padovand4cab382016-04-28 10:46:54 -0300375{
376 strlcpy(info->obj_name, fence->ops->get_timeline_name(fence),
377 sizeof(info->obj_name));
378 strlcpy(info->driver_name, fence->ops->get_driver_name(fence),
379 sizeof(info->driver_name));
380 if (fence_is_signaled(fence))
381 info->status = fence->status >= 0 ? 1 : fence->status;
382 else
383 info->status = 0;
384 info->timestamp_ns = ktime_to_ns(fence->timestamp);
385}
386
387static long sync_file_ioctl_fence_info(struct sync_file *sync_file,
Gustavo Padovan92e06212016-04-28 10:46:56 -0300388 unsigned long arg)
Gustavo Padovand4cab382016-04-28 10:46:54 -0300389{
390 struct sync_file_info info;
391 struct sync_fence_info *fence_info = NULL;
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300392 struct fence **fences;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300393 __u32 size;
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300394 int num_fences, ret, i;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300395
396 if (copy_from_user(&info, (void __user *)arg, sizeof(info)))
397 return -EFAULT;
398
399 if (info.flags || info.pad)
400 return -EINVAL;
401
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300402 fences = get_fences(sync_file, &num_fences);
403
Gustavo Padovand4cab382016-04-28 10:46:54 -0300404 /*
405 * Passing num_fences = 0 means that userspace doesn't want to
406 * retrieve any sync_fence_info. If num_fences = 0 we skip filling
407 * sync_fence_info and return the actual number of fences on
408 * info->num_fences.
409 */
410 if (!info.num_fences)
411 goto no_fences;
412
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300413 if (info.num_fences < num_fences)
Gustavo Padovand4cab382016-04-28 10:46:54 -0300414 return -EINVAL;
415
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300416 size = num_fences * sizeof(*fence_info);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300417 fence_info = kzalloc(size, GFP_KERNEL);
418 if (!fence_info)
419 return -ENOMEM;
420
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300421 for (i = 0; i < num_fences; i++)
422 sync_fill_fence_info(fences[i], &fence_info[i]);
Gustavo Padovand4cab382016-04-28 10:46:54 -0300423
424 if (copy_to_user(u64_to_user_ptr(info.sync_fence_info), fence_info,
425 size)) {
426 ret = -EFAULT;
427 goto out;
428 }
429
430no_fences:
431 strlcpy(info.name, sync_file->name, sizeof(info.name));
Gustavo Padovana02b9dc2016-08-05 10:39:35 -0300432 info.status = fence_is_signaled(sync_file->fence);
433 info.num_fences = num_fences;
Gustavo Padovand4cab382016-04-28 10:46:54 -0300434
435 if (copy_to_user((void __user *)arg, &info, sizeof(info)))
436 ret = -EFAULT;
437 else
438 ret = 0;
439
440out:
441 kfree(fence_info);
442
443 return ret;
444}
445
446static long sync_file_ioctl(struct file *file, unsigned int cmd,
Gustavo Padovan92e06212016-04-28 10:46:56 -0300447 unsigned long arg)
Gustavo Padovand4cab382016-04-28 10:46:54 -0300448{
449 struct sync_file *sync_file = file->private_data;
450
451 switch (cmd) {
452 case SYNC_IOC_MERGE:
453 return sync_file_ioctl_merge(sync_file, arg);
454
455 case SYNC_IOC_FILE_INFO:
456 return sync_file_ioctl_fence_info(sync_file, arg);
457
458 default:
459 return -ENOTTY;
460 }
461}
462
463static const struct file_operations sync_file_fops = {
464 .release = sync_file_release,
465 .poll = sync_file_poll,
466 .unlocked_ioctl = sync_file_ioctl,
467 .compat_ioctl = sync_file_ioctl,
468};
469