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786d7257 | 1 | /* |
04a5faa8 | 2 | * Copyright (C) 2012-2014 Canonical Ltd (Maarten Lankhorst) |
786d7257 ML |
3 | * |
4 | * Based on bo.c which bears the following copyright notice, | |
5 | * but is dual licensed: | |
6 | * | |
7 | * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA | |
8 | * All Rights Reserved. | |
9 | * | |
10 | * Permission is hereby granted, free of charge, to any person obtaining a | |
11 | * copy of this software and associated documentation files (the | |
12 | * "Software"), to deal in the Software without restriction, including | |
13 | * without limitation the rights to use, copy, modify, merge, publish, | |
14 | * distribute, sub license, and/or sell copies of the Software, and to | |
15 | * permit persons to whom the Software is furnished to do so, subject to | |
16 | * the following conditions: | |
17 | * | |
18 | * The above copyright notice and this permission notice (including the | |
19 | * next paragraph) shall be included in all copies or substantial portions | |
20 | * of the Software. | |
21 | * | |
22 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
23 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
24 | * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL | |
25 | * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, | |
26 | * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR | |
27 | * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE | |
28 | * USE OR OTHER DEALINGS IN THE SOFTWARE. | |
29 | * | |
30 | **************************************************************************/ | |
31 | /* | |
32 | * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> | |
33 | */ | |
34 | ||
35 | #include <linux/reservation.h> | |
36 | #include <linux/export.h> | |
37 | ||
dad6c394 RC |
38 | /** |
39 | * DOC: Reservation Object Overview | |
40 | * | |
41 | * The reservation object provides a mechanism to manage shared and | |
42 | * exclusive fences associated with a buffer. A reservation object | |
43 | * can have attached one exclusive fence (normally associated with | |
44 | * write operations) or N shared fences (read operations). The RCU | |
45 | * mechanism is used to protect read access to fences from locked | |
46 | * write-side updates. | |
47 | */ | |
48 | ||
786d7257 ML |
49 | DEFINE_WW_CLASS(reservation_ww_class); |
50 | EXPORT_SYMBOL(reservation_ww_class); | |
04a5faa8 | 51 | |
3c3b177a ML |
52 | struct lock_class_key reservation_seqcount_class; |
53 | EXPORT_SYMBOL(reservation_seqcount_class); | |
54 | ||
55 | const char reservation_seqcount_string[] = "reservation_seqcount"; | |
56 | EXPORT_SYMBOL(reservation_seqcount_string); | |
dad6c394 RC |
57 | |
58 | /** | |
59 | * reservation_object_reserve_shared - Reserve space to add a shared | |
60 | * fence to a reservation_object. | |
61 | * @obj: reservation object | |
62 | * | |
63 | * Should be called before reservation_object_add_shared_fence(). Must | |
64 | * be called with obj->lock held. | |
65 | * | |
66 | * RETURNS | |
67 | * Zero for success, or -errno | |
04a5faa8 ML |
68 | */ |
69 | int reservation_object_reserve_shared(struct reservation_object *obj) | |
70 | { | |
71 | struct reservation_object_list *fobj, *old; | |
72 | u32 max; | |
73 | ||
74 | old = reservation_object_get_list(obj); | |
75 | ||
76 | if (old && old->shared_max) { | |
77 | if (old->shared_count < old->shared_max) { | |
78 | /* perform an in-place update */ | |
79 | kfree(obj->staged); | |
80 | obj->staged = NULL; | |
81 | return 0; | |
82 | } else | |
83 | max = old->shared_max * 2; | |
84 | } else | |
85 | max = 4; | |
86 | ||
87 | /* | |
88 | * resize obj->staged or allocate if it doesn't exist, | |
89 | * noop if already correct size | |
90 | */ | |
91 | fobj = krealloc(obj->staged, offsetof(typeof(*fobj), shared[max]), | |
92 | GFP_KERNEL); | |
93 | if (!fobj) | |
94 | return -ENOMEM; | |
95 | ||
96 | obj->staged = fobj; | |
97 | fobj->shared_max = max; | |
98 | return 0; | |
99 | } | |
100 | EXPORT_SYMBOL(reservation_object_reserve_shared); | |
101 | ||
102 | static void | |
103 | reservation_object_add_shared_inplace(struct reservation_object *obj, | |
104 | struct reservation_object_list *fobj, | |
f54d1867 | 105 | struct dma_fence *fence) |
04a5faa8 | 106 | { |
ca25fe5e CK |
107 | struct dma_fence *signaled = NULL; |
108 | u32 i, signaled_idx; | |
04a5faa8 | 109 | |
f54d1867 | 110 | dma_fence_get(fence); |
3c3b177a ML |
111 | |
112 | preempt_disable(); | |
113 | write_seqcount_begin(&obj->seq); | |
114 | ||
04a5faa8 | 115 | for (i = 0; i < fobj->shared_count; ++i) { |
f54d1867 | 116 | struct dma_fence *old_fence; |
04a5faa8 | 117 | |
3c3b177a ML |
118 | old_fence = rcu_dereference_protected(fobj->shared[i], |
119 | reservation_object_held(obj)); | |
04a5faa8 | 120 | |
3c3b177a ML |
121 | if (old_fence->context == fence->context) { |
122 | /* memory barrier is added by write_seqcount_begin */ | |
123 | RCU_INIT_POINTER(fobj->shared[i], fence); | |
124 | write_seqcount_end(&obj->seq); | |
125 | preempt_enable(); | |
04a5faa8 | 126 | |
f54d1867 | 127 | dma_fence_put(old_fence); |
04a5faa8 ML |
128 | return; |
129 | } | |
ca25fe5e CK |
130 | |
131 | if (!signaled && dma_fence_is_signaled(old_fence)) { | |
132 | signaled = old_fence; | |
133 | signaled_idx = i; | |
134 | } | |
04a5faa8 ML |
135 | } |
136 | ||
04a5faa8 | 137 | /* |
3c3b177a ML |
138 | * memory barrier is added by write_seqcount_begin, |
139 | * fobj->shared_count is protected by this lock too | |
04a5faa8 | 140 | */ |
ca25fe5e CK |
141 | if (signaled) { |
142 | RCU_INIT_POINTER(fobj->shared[signaled_idx], fence); | |
143 | } else { | |
144 | RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); | |
145 | fobj->shared_count++; | |
146 | } | |
3c3b177a ML |
147 | |
148 | write_seqcount_end(&obj->seq); | |
149 | preempt_enable(); | |
ca25fe5e CK |
150 | |
151 | dma_fence_put(signaled); | |
04a5faa8 ML |
152 | } |
153 | ||
154 | static void | |
155 | reservation_object_add_shared_replace(struct reservation_object *obj, | |
156 | struct reservation_object_list *old, | |
157 | struct reservation_object_list *fobj, | |
f54d1867 | 158 | struct dma_fence *fence) |
04a5faa8 | 159 | { |
4d9c62e8 | 160 | unsigned i, j, k; |
04a5faa8 | 161 | |
f54d1867 | 162 | dma_fence_get(fence); |
04a5faa8 ML |
163 | |
164 | if (!old) { | |
3c3b177a | 165 | RCU_INIT_POINTER(fobj->shared[0], fence); |
04a5faa8 ML |
166 | fobj->shared_count = 1; |
167 | goto done; | |
168 | } | |
169 | ||
170 | /* | |
171 | * no need to bump fence refcounts, rcu_read access | |
172 | * requires the use of kref_get_unless_zero, and the | |
173 | * references from the old struct are carried over to | |
174 | * the new. | |
175 | */ | |
4d9c62e8 | 176 | for (i = 0, j = 0, k = fobj->shared_max; i < old->shared_count; ++i) { |
f54d1867 | 177 | struct dma_fence *check; |
3c3b177a ML |
178 | |
179 | check = rcu_dereference_protected(old->shared[i], | |
180 | reservation_object_held(obj)); | |
181 | ||
4d9c62e8 CK |
182 | if (check->context == fence->context || |
183 | dma_fence_is_signaled(check)) | |
184 | RCU_INIT_POINTER(fobj->shared[--k], check); | |
185 | else | |
186 | RCU_INIT_POINTER(fobj->shared[j++], check); | |
04a5faa8 | 187 | } |
4d9c62e8 CK |
188 | fobj->shared_count = j; |
189 | RCU_INIT_POINTER(fobj->shared[fobj->shared_count], fence); | |
190 | fobj->shared_count++; | |
04a5faa8 ML |
191 | |
192 | done: | |
3c3b177a ML |
193 | preempt_disable(); |
194 | write_seqcount_begin(&obj->seq); | |
195 | /* | |
196 | * RCU_INIT_POINTER can be used here, | |
197 | * seqcount provides the necessary barriers | |
198 | */ | |
199 | RCU_INIT_POINTER(obj->fence, fobj); | |
200 | write_seqcount_end(&obj->seq); | |
201 | preempt_enable(); | |
202 | ||
4d9c62e8 CK |
203 | if (!old) |
204 | return; | |
3c3b177a | 205 | |
4d9c62e8 CK |
206 | /* Drop the references to the signaled fences */ |
207 | for (i = k; i < fobj->shared_max; ++i) { | |
208 | struct dma_fence *f; | |
209 | ||
210 | f = rcu_dereference_protected(fobj->shared[i], | |
211 | reservation_object_held(obj)); | |
212 | dma_fence_put(f); | |
213 | } | |
214 | kfree_rcu(old, rcu); | |
04a5faa8 ML |
215 | } |
216 | ||
dad6c394 RC |
217 | /** |
218 | * reservation_object_add_shared_fence - Add a fence to a shared slot | |
219 | * @obj: the reservation object | |
220 | * @fence: the shared fence to add | |
221 | * | |
04a5faa8 | 222 | * Add a fence to a shared slot, obj->lock must be held, and |
f5bef0b8 | 223 | * reservation_object_reserve_shared() has been called. |
04a5faa8 ML |
224 | */ |
225 | void reservation_object_add_shared_fence(struct reservation_object *obj, | |
f54d1867 | 226 | struct dma_fence *fence) |
04a5faa8 ML |
227 | { |
228 | struct reservation_object_list *old, *fobj = obj->staged; | |
229 | ||
230 | old = reservation_object_get_list(obj); | |
231 | obj->staged = NULL; | |
232 | ||
233 | if (!fobj) { | |
3c3b177a | 234 | BUG_ON(old->shared_count >= old->shared_max); |
04a5faa8 ML |
235 | reservation_object_add_shared_inplace(obj, old, fence); |
236 | } else | |
237 | reservation_object_add_shared_replace(obj, old, fobj, fence); | |
238 | } | |
239 | EXPORT_SYMBOL(reservation_object_add_shared_fence); | |
240 | ||
dad6c394 RC |
241 | /** |
242 | * reservation_object_add_excl_fence - Add an exclusive fence. | |
243 | * @obj: the reservation object | |
244 | * @fence: the shared fence to add | |
245 | * | |
246 | * Add a fence to the exclusive slot. The obj->lock must be held. | |
247 | */ | |
04a5faa8 | 248 | void reservation_object_add_excl_fence(struct reservation_object *obj, |
f54d1867 | 249 | struct dma_fence *fence) |
04a5faa8 | 250 | { |
f54d1867 | 251 | struct dma_fence *old_fence = reservation_object_get_excl(obj); |
04a5faa8 ML |
252 | struct reservation_object_list *old; |
253 | u32 i = 0; | |
254 | ||
255 | old = reservation_object_get_list(obj); | |
3c3b177a | 256 | if (old) |
04a5faa8 | 257 | i = old->shared_count; |
04a5faa8 ML |
258 | |
259 | if (fence) | |
f54d1867 | 260 | dma_fence_get(fence); |
04a5faa8 | 261 | |
3c3b177a ML |
262 | preempt_disable(); |
263 | write_seqcount_begin(&obj->seq); | |
264 | /* write_seqcount_begin provides the necessary memory barrier */ | |
265 | RCU_INIT_POINTER(obj->fence_excl, fence); | |
266 | if (old) | |
267 | old->shared_count = 0; | |
268 | write_seqcount_end(&obj->seq); | |
269 | preempt_enable(); | |
04a5faa8 ML |
270 | |
271 | /* inplace update, no shared fences */ | |
272 | while (i--) | |
f54d1867 | 273 | dma_fence_put(rcu_dereference_protected(old->shared[i], |
3c3b177a | 274 | reservation_object_held(obj))); |
04a5faa8 | 275 | |
f3e31b73 | 276 | dma_fence_put(old_fence); |
04a5faa8 ML |
277 | } |
278 | EXPORT_SYMBOL(reservation_object_add_excl_fence); | |
3c3b177a | 279 | |
7faf952a CK |
280 | /** |
281 | * reservation_object_copy_fences - Copy all fences from src to dst. | |
282 | * @dst: the destination reservation object | |
283 | * @src: the source reservation object | |
284 | * | |
39e16ba1 | 285 | * Copy all fences from src to dst. dst-lock must be held. |
7faf952a CK |
286 | */ |
287 | int reservation_object_copy_fences(struct reservation_object *dst, | |
288 | struct reservation_object *src) | |
289 | { | |
290 | struct reservation_object_list *src_list, *dst_list; | |
291 | struct dma_fence *old, *new; | |
292 | size_t size; | |
293 | unsigned i; | |
294 | ||
39e16ba1 CK |
295 | rcu_read_lock(); |
296 | src_list = rcu_dereference(src->fence); | |
7faf952a | 297 | |
39e16ba1 | 298 | retry: |
7faf952a | 299 | if (src_list) { |
39e16ba1 CK |
300 | unsigned shared_count = src_list->shared_count; |
301 | ||
302 | size = offsetof(typeof(*src_list), shared[shared_count]); | |
303 | rcu_read_unlock(); | |
304 | ||
7faf952a CK |
305 | dst_list = kmalloc(size, GFP_KERNEL); |
306 | if (!dst_list) | |
307 | return -ENOMEM; | |
308 | ||
39e16ba1 CK |
309 | rcu_read_lock(); |
310 | src_list = rcu_dereference(src->fence); | |
311 | if (!src_list || src_list->shared_count > shared_count) { | |
312 | kfree(dst_list); | |
313 | goto retry; | |
314 | } | |
315 | ||
316 | dst_list->shared_count = 0; | |
317 | dst_list->shared_max = shared_count; | |
318 | for (i = 0; i < src_list->shared_count; ++i) { | |
319 | struct dma_fence *fence; | |
320 | ||
321 | fence = rcu_dereference(src_list->shared[i]); | |
322 | if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, | |
323 | &fence->flags)) | |
324 | continue; | |
325 | ||
326 | if (!dma_fence_get_rcu(fence)) { | |
327 | kfree(dst_list); | |
328 | src_list = rcu_dereference(src->fence); | |
329 | goto retry; | |
330 | } | |
331 | ||
332 | if (dma_fence_is_signaled(fence)) { | |
333 | dma_fence_put(fence); | |
334 | continue; | |
335 | } | |
336 | ||
ad46d7b8 | 337 | rcu_assign_pointer(dst_list->shared[dst_list->shared_count++], fence); |
39e16ba1 | 338 | } |
7faf952a CK |
339 | } else { |
340 | dst_list = NULL; | |
341 | } | |
342 | ||
39e16ba1 CK |
343 | new = dma_fence_get_rcu_safe(&src->fence_excl); |
344 | rcu_read_unlock(); | |
345 | ||
7faf952a CK |
346 | kfree(dst->staged); |
347 | dst->staged = NULL; | |
348 | ||
349 | src_list = reservation_object_get_list(dst); | |
7faf952a | 350 | old = reservation_object_get_excl(dst); |
7faf952a CK |
351 | |
352 | preempt_disable(); | |
353 | write_seqcount_begin(&dst->seq); | |
354 | /* write_seqcount_begin provides the necessary memory barrier */ | |
355 | RCU_INIT_POINTER(dst->fence_excl, new); | |
356 | RCU_INIT_POINTER(dst->fence, dst_list); | |
357 | write_seqcount_end(&dst->seq); | |
358 | preempt_enable(); | |
359 | ||
360 | if (src_list) | |
361 | kfree_rcu(src_list, rcu); | |
362 | dma_fence_put(old); | |
363 | ||
364 | return 0; | |
365 | } | |
366 | EXPORT_SYMBOL(reservation_object_copy_fences); | |
367 | ||
dad6c394 RC |
368 | /** |
369 | * reservation_object_get_fences_rcu - Get an object's shared and exclusive | |
370 | * fences without update side lock held | |
371 | * @obj: the reservation object | |
372 | * @pfence_excl: the returned exclusive fence (or NULL) | |
373 | * @pshared_count: the number of shared fences returned | |
374 | * @pshared: the array of shared fence ptrs returned (array is krealloc'd to | |
375 | * the required size, and must be freed by caller) | |
376 | * | |
a35f2f34 CK |
377 | * Retrieve all fences from the reservation object. If the pointer for the |
378 | * exclusive fence is not specified the fence is put into the array of the | |
379 | * shared fences as well. Returns either zero or -ENOMEM. | |
dad6c394 | 380 | */ |
3c3b177a | 381 | int reservation_object_get_fences_rcu(struct reservation_object *obj, |
f54d1867 | 382 | struct dma_fence **pfence_excl, |
3c3b177a | 383 | unsigned *pshared_count, |
f54d1867 | 384 | struct dma_fence ***pshared) |
3c3b177a | 385 | { |
f54d1867 CW |
386 | struct dma_fence **shared = NULL; |
387 | struct dma_fence *fence_excl; | |
fedf5413 CW |
388 | unsigned int shared_count; |
389 | int ret = 1; | |
3c3b177a | 390 | |
fedf5413 | 391 | do { |
3c3b177a | 392 | struct reservation_object_list *fobj; |
a35f2f34 CK |
393 | unsigned int i, seq; |
394 | size_t sz = 0; | |
3c3b177a | 395 | |
fedf5413 | 396 | shared_count = i = 0; |
3c3b177a ML |
397 | |
398 | rcu_read_lock(); | |
fedf5413 CW |
399 | seq = read_seqcount_begin(&obj->seq); |
400 | ||
401 | fence_excl = rcu_dereference(obj->fence_excl); | |
f54d1867 | 402 | if (fence_excl && !dma_fence_get_rcu(fence_excl)) |
fedf5413 | 403 | goto unlock; |
3c3b177a ML |
404 | |
405 | fobj = rcu_dereference(obj->fence); | |
a35f2f34 CK |
406 | if (fobj) |
407 | sz += sizeof(*shared) * fobj->shared_max; | |
408 | ||
409 | if (!pfence_excl && fence_excl) | |
410 | sz += sizeof(*shared); | |
411 | ||
412 | if (sz) { | |
f54d1867 | 413 | struct dma_fence **nshared; |
3c3b177a ML |
414 | |
415 | nshared = krealloc(shared, sz, | |
416 | GFP_NOWAIT | __GFP_NOWARN); | |
417 | if (!nshared) { | |
418 | rcu_read_unlock(); | |
419 | nshared = krealloc(shared, sz, GFP_KERNEL); | |
420 | if (nshared) { | |
421 | shared = nshared; | |
422 | continue; | |
423 | } | |
424 | ||
425 | ret = -ENOMEM; | |
3c3b177a ML |
426 | break; |
427 | } | |
428 | shared = nshared; | |
a35f2f34 | 429 | shared_count = fobj ? fobj->shared_count : 0; |
3c3b177a | 430 | for (i = 0; i < shared_count; ++i) { |
fedf5413 | 431 | shared[i] = rcu_dereference(fobj->shared[i]); |
f54d1867 | 432 | if (!dma_fence_get_rcu(shared[i])) |
fedf5413 | 433 | break; |
3c3b177a | 434 | } |
a35f2f34 CK |
435 | |
436 | if (!pfence_excl && fence_excl) { | |
437 | shared[i] = fence_excl; | |
438 | fence_excl = NULL; | |
439 | ++i; | |
440 | ++shared_count; | |
441 | } | |
fedf5413 | 442 | } |
3c3b177a | 443 | |
fedf5413 CW |
444 | if (i != shared_count || read_seqcount_retry(&obj->seq, seq)) { |
445 | while (i--) | |
f54d1867 CW |
446 | dma_fence_put(shared[i]); |
447 | dma_fence_put(fence_excl); | |
fedf5413 CW |
448 | goto unlock; |
449 | } | |
450 | ||
451 | ret = 0; | |
3c3b177a ML |
452 | unlock: |
453 | rcu_read_unlock(); | |
fedf5413 CW |
454 | } while (ret); |
455 | ||
456 | if (!shared_count) { | |
3c3b177a | 457 | kfree(shared); |
fedf5413 | 458 | shared = NULL; |
3c3b177a | 459 | } |
fedf5413 CW |
460 | |
461 | *pshared_count = shared_count; | |
462 | *pshared = shared; | |
a35f2f34 CK |
463 | if (pfence_excl) |
464 | *pfence_excl = fence_excl; | |
3c3b177a ML |
465 | |
466 | return ret; | |
467 | } | |
468 | EXPORT_SYMBOL_GPL(reservation_object_get_fences_rcu); | |
469 | ||
dad6c394 RC |
470 | /** |
471 | * reservation_object_wait_timeout_rcu - Wait on reservation's objects | |
472 | * shared and/or exclusive fences. | |
473 | * @obj: the reservation object | |
474 | * @wait_all: if true, wait on all fences, else wait on just exclusive fence | |
475 | * @intr: if true, do interruptible wait | |
476 | * @timeout: timeout value in jiffies or zero to return immediately | |
477 | * | |
478 | * RETURNS | |
479 | * Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or | |
480 | * greater than zer on success. | |
481 | */ | |
3c3b177a ML |
482 | long reservation_object_wait_timeout_rcu(struct reservation_object *obj, |
483 | bool wait_all, bool intr, | |
484 | unsigned long timeout) | |
485 | { | |
f54d1867 | 486 | struct dma_fence *fence; |
5bffee86 | 487 | unsigned seq, shared_count; |
06a66b5c | 488 | long ret = timeout ? timeout : 1; |
5bffee86 | 489 | int i; |
fb8b7d2b | 490 | |
3c3b177a | 491 | retry: |
3c3b177a ML |
492 | shared_count = 0; |
493 | seq = read_seqcount_begin(&obj->seq); | |
494 | rcu_read_lock(); | |
5bffee86 | 495 | i = -1; |
3c3b177a | 496 | |
b88fa004 CK |
497 | fence = rcu_dereference(obj->fence_excl); |
498 | if (fence && !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) { | |
499 | if (!dma_fence_get_rcu(fence)) | |
500 | goto unlock_retry; | |
501 | ||
502 | if (dma_fence_is_signaled(fence)) { | |
503 | dma_fence_put(fence); | |
504 | fence = NULL; | |
505 | } | |
506 | ||
507 | } else { | |
508 | fence = NULL; | |
509 | } | |
510 | ||
5bffee86 | 511 | if (wait_all) { |
5136629d JT |
512 | struct reservation_object_list *fobj = |
513 | rcu_dereference(obj->fence); | |
3c3b177a ML |
514 | |
515 | if (fobj) | |
516 | shared_count = fobj->shared_count; | |
517 | ||
5bffee86 | 518 | for (i = 0; !fence && i < shared_count; ++i) { |
f54d1867 | 519 | struct dma_fence *lfence = rcu_dereference(fobj->shared[i]); |
3c3b177a | 520 | |
f54d1867 CW |
521 | if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, |
522 | &lfence->flags)) | |
3c3b177a ML |
523 | continue; |
524 | ||
f54d1867 | 525 | if (!dma_fence_get_rcu(lfence)) |
3c3b177a ML |
526 | goto unlock_retry; |
527 | ||
f54d1867 CW |
528 | if (dma_fence_is_signaled(lfence)) { |
529 | dma_fence_put(lfence); | |
3c3b177a ML |
530 | continue; |
531 | } | |
532 | ||
533 | fence = lfence; | |
534 | break; | |
535 | } | |
536 | } | |
537 | ||
3c3b177a ML |
538 | rcu_read_unlock(); |
539 | if (fence) { | |
1cec20f0 | 540 | if (read_seqcount_retry(&obj->seq, seq)) { |
f54d1867 | 541 | dma_fence_put(fence); |
1cec20f0 CW |
542 | goto retry; |
543 | } | |
544 | ||
f54d1867 CW |
545 | ret = dma_fence_wait_timeout(fence, intr, ret); |
546 | dma_fence_put(fence); | |
3c3b177a ML |
547 | if (ret > 0 && wait_all && (i + 1 < shared_count)) |
548 | goto retry; | |
549 | } | |
550 | return ret; | |
551 | ||
552 | unlock_retry: | |
553 | rcu_read_unlock(); | |
554 | goto retry; | |
555 | } | |
556 | EXPORT_SYMBOL_GPL(reservation_object_wait_timeout_rcu); | |
557 | ||
558 | ||
559 | static inline int | |
f54d1867 | 560 | reservation_object_test_signaled_single(struct dma_fence *passed_fence) |
3c3b177a | 561 | { |
f54d1867 | 562 | struct dma_fence *fence, *lfence = passed_fence; |
3c3b177a ML |
563 | int ret = 1; |
564 | ||
f54d1867 CW |
565 | if (!test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &lfence->flags)) { |
566 | fence = dma_fence_get_rcu(lfence); | |
3c3b177a ML |
567 | if (!fence) |
568 | return -1; | |
569 | ||
f54d1867 CW |
570 | ret = !!dma_fence_is_signaled(fence); |
571 | dma_fence_put(fence); | |
3c3b177a ML |
572 | } |
573 | return ret; | |
574 | } | |
575 | ||
dad6c394 RC |
576 | /** |
577 | * reservation_object_test_signaled_rcu - Test if a reservation object's | |
578 | * fences have been signaled. | |
579 | * @obj: the reservation object | |
580 | * @test_all: if true, test all fences, otherwise only test the exclusive | |
581 | * fence | |
582 | * | |
583 | * RETURNS | |
584 | * true if all fences signaled, else false | |
585 | */ | |
3c3b177a ML |
586 | bool reservation_object_test_signaled_rcu(struct reservation_object *obj, |
587 | bool test_all) | |
588 | { | |
589 | unsigned seq, shared_count; | |
b68d8379 | 590 | int ret; |
3c3b177a | 591 | |
b68d8379 | 592 | rcu_read_lock(); |
3c3b177a | 593 | retry: |
b68d8379 | 594 | ret = true; |
3c3b177a ML |
595 | shared_count = 0; |
596 | seq = read_seqcount_begin(&obj->seq); | |
3c3b177a ML |
597 | |
598 | if (test_all) { | |
599 | unsigned i; | |
600 | ||
5136629d JT |
601 | struct reservation_object_list *fobj = |
602 | rcu_dereference(obj->fence); | |
3c3b177a ML |
603 | |
604 | if (fobj) | |
605 | shared_count = fobj->shared_count; | |
606 | ||
3c3b177a | 607 | for (i = 0; i < shared_count; ++i) { |
f54d1867 | 608 | struct dma_fence *fence = rcu_dereference(fobj->shared[i]); |
3c3b177a ML |
609 | |
610 | ret = reservation_object_test_signaled_single(fence); | |
611 | if (ret < 0) | |
b68d8379 | 612 | goto retry; |
3c3b177a ML |
613 | else if (!ret) |
614 | break; | |
615 | } | |
616 | ||
b68d8379 CW |
617 | if (read_seqcount_retry(&obj->seq, seq)) |
618 | goto retry; | |
3c3b177a ML |
619 | } |
620 | ||
621 | if (!shared_count) { | |
f54d1867 | 622 | struct dma_fence *fence_excl = rcu_dereference(obj->fence_excl); |
3c3b177a | 623 | |
3c3b177a | 624 | if (fence_excl) { |
5136629d JT |
625 | ret = reservation_object_test_signaled_single( |
626 | fence_excl); | |
3c3b177a | 627 | if (ret < 0) |
b68d8379 CW |
628 | goto retry; |
629 | ||
630 | if (read_seqcount_retry(&obj->seq, seq)) | |
631 | goto retry; | |
3c3b177a ML |
632 | } |
633 | } | |
634 | ||
635 | rcu_read_unlock(); | |
636 | return ret; | |
3c3b177a ML |
637 | } |
638 | EXPORT_SYMBOL_GPL(reservation_object_test_signaled_rcu); |