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> |
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); |
45 | ||
a02b9dc9 GP |
46 | INIT_LIST_HEAD(&sync_file->cb.node); |
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; |
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 |
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 | { |
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, |
185 | int *num_fences) | |
a02b9dc9 | 186 | { |
f54d1867 CW |
187 | if (dma_fence_is_array(sync_file->fence)) { |
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, |
199 | int *i, struct dma_fence *fence) | |
a02b9dc9 GP |
200 | { |
201 | fences[*i] = fence; | |
202 | ||
f54d1867 CW |
203 | if (!dma_fence_is_signaled(fence)) { |
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]; |
250 | struct dma_fence *pt_b = b_fences[i_b]; | |
d4cab38e GP |
251 | |
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 | } |
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); |
309 | dma_fence_put(sync_file->fence); | |
d4cab38e | 310 | kfree(sync_file); |
d4cab38e | 311 | |
d4cab38e GP |
312 | return 0; |
313 | } | |
314 | ||
afc9a42b | 315 | static __poll_t sync_file_poll(struct file *file, poll_table *wait) |
d4cab38e GP |
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) && |
322 | !test_and_set_bit(POLL_ENABLED, &sync_file->flags)) { | |
f54d1867 CW |
323 | if (dma_fence_add_callback(sync_file->fence, &sync_file->cb, |
324 | fence_check_cb_func) < 0) | |
e2416553 GP |
325 | wake_up_all(&sync_file->wq); |
326 | } | |
d4cab38e | 327 | |
a9a08845 | 328 | return dma_fence_is_signaled(sync_file->fence) ? EPOLLIN : 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 | |
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 | |
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); |
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) { |
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; |
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 | }; |