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88071539 TH |
1 | /************************************************************************** |
2 | * | |
65981f76 | 3 | * Copyright (c) 2009-2013 VMware, Inc., Palo Alto, CA., USA |
88071539 TH |
4 | * All Rights Reserved. |
5 | * | |
6 | * Permission is hereby granted, free of charge, to any person obtaining a | |
7 | * copy of this software and associated documentation files (the | |
8 | * "Software"), to deal in the Software without restriction, including | |
9 | * without limitation the rights to use, copy, modify, merge, publish, | |
10 | * distribute, sub license, and/or sell copies of the Software, and to | |
11 | * permit persons to whom the Software is furnished to do so, subject to | |
12 | * the following conditions: | |
13 | * | |
14 | * The above copyright notice and this permission notice (including the | |
15 | * next paragraph) shall be included in all copies or substantial portions | |
16 | * of the Software. | |
17 | * | |
18 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
19 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
20 | * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL | |
21 | * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, | |
22 | * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR | |
23 | * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE | |
24 | * USE OR OTHER DEALINGS IN THE SOFTWARE. | |
25 | * | |
26 | **************************************************************************/ | |
27 | /* | |
28 | * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> | |
65981f76 TH |
29 | * |
30 | * While no substantial code is shared, the prime code is inspired by | |
31 | * drm_prime.c, with | |
32 | * Authors: | |
33 | * Dave Airlie <airlied@redhat.com> | |
34 | * Rob Clark <rob.clark@linaro.org> | |
88071539 TH |
35 | */ |
36 | /** @file ttm_ref_object.c | |
37 | * | |
38 | * Base- and reference object implementation for the various | |
39 | * ttm objects. Implements reference counting, minimal security checks | |
40 | * and release on file close. | |
41 | */ | |
42 | ||
65981f76 | 43 | |
88071539 TH |
44 | /** |
45 | * struct ttm_object_file | |
46 | * | |
47 | * @tdev: Pointer to the ttm_object_device. | |
48 | * | |
49 | * @lock: Lock that protects the ref_list list and the | |
50 | * ref_hash hash tables. | |
51 | * | |
52 | * @ref_list: List of ttm_ref_objects to be destroyed at | |
53 | * file release. | |
54 | * | |
55 | * @ref_hash: Hash tables of ref objects, one per ttm_ref_type, | |
56 | * for fast lookup of ref objects given a base object. | |
57 | */ | |
58 | ||
25d0479a JP |
59 | #define pr_fmt(fmt) "[TTM] " fmt |
60 | ||
760285e7 DH |
61 | #include <drm/ttm/ttm_object.h> |
62 | #include <drm/ttm/ttm_module.h> | |
88071539 TH |
63 | #include <linux/list.h> |
64 | #include <linux/spinlock.h> | |
65 | #include <linux/slab.h> | |
66 | #include <linux/module.h> | |
60063497 | 67 | #include <linux/atomic.h> |
88071539 TH |
68 | |
69 | struct ttm_object_file { | |
70 | struct ttm_object_device *tdev; | |
05efb1ab | 71 | spinlock_t lock; |
88071539 TH |
72 | struct list_head ref_list; |
73 | struct drm_open_hash ref_hash[TTM_REF_NUM]; | |
74 | struct kref refcount; | |
75 | }; | |
76 | ||
77 | /** | |
78 | * struct ttm_object_device | |
79 | * | |
80 | * @object_lock: lock that protects the object_hash hash table. | |
81 | * | |
82 | * @object_hash: hash table for fast lookup of object global names. | |
83 | * | |
84 | * @object_count: Per device object count. | |
85 | * | |
86 | * This is the per-device data structure needed for ttm object management. | |
87 | */ | |
88 | ||
89 | struct ttm_object_device { | |
cdad0521 | 90 | spinlock_t object_lock; |
88071539 TH |
91 | struct drm_open_hash object_hash; |
92 | atomic_t object_count; | |
93 | struct ttm_mem_global *mem_glob; | |
65981f76 TH |
94 | struct dma_buf_ops ops; |
95 | void (*dmabuf_release)(struct dma_buf *dma_buf); | |
96 | size_t dma_buf_size; | |
88071539 TH |
97 | }; |
98 | ||
99 | /** | |
100 | * struct ttm_ref_object | |
101 | * | |
102 | * @hash: Hash entry for the per-file object reference hash. | |
103 | * | |
104 | * @head: List entry for the per-file list of ref-objects. | |
105 | * | |
106 | * @kref: Ref count. | |
107 | * | |
108 | * @obj: Base object this ref object is referencing. | |
109 | * | |
110 | * @ref_type: Type of ref object. | |
111 | * | |
112 | * This is similar to an idr object, but it also has a hash table entry | |
113 | * that allows lookup with a pointer to the referenced object as a key. In | |
114 | * that way, one can easily detect whether a base object is referenced by | |
115 | * a particular ttm_object_file. It also carries a ref count to avoid creating | |
116 | * multiple ref objects if a ttm_object_file references the same base | |
117 | * object more than once. | |
118 | */ | |
119 | ||
120 | struct ttm_ref_object { | |
05efb1ab | 121 | struct rcu_head rcu_head; |
88071539 TH |
122 | struct drm_hash_item hash; |
123 | struct list_head head; | |
124 | struct kref kref; | |
88071539 | 125 | enum ttm_ref_type ref_type; |
dd5fde60 | 126 | struct ttm_base_object *obj; |
88071539 TH |
127 | struct ttm_object_file *tfile; |
128 | }; | |
129 | ||
65981f76 TH |
130 | static void ttm_prime_dmabuf_release(struct dma_buf *dma_buf); |
131 | ||
88071539 TH |
132 | static inline struct ttm_object_file * |
133 | ttm_object_file_ref(struct ttm_object_file *tfile) | |
134 | { | |
135 | kref_get(&tfile->refcount); | |
136 | return tfile; | |
137 | } | |
138 | ||
139 | static void ttm_object_file_destroy(struct kref *kref) | |
140 | { | |
141 | struct ttm_object_file *tfile = | |
142 | container_of(kref, struct ttm_object_file, refcount); | |
143 | ||
144 | kfree(tfile); | |
145 | } | |
146 | ||
147 | ||
148 | static inline void ttm_object_file_unref(struct ttm_object_file **p_tfile) | |
149 | { | |
150 | struct ttm_object_file *tfile = *p_tfile; | |
151 | ||
152 | *p_tfile = NULL; | |
153 | kref_put(&tfile->refcount, ttm_object_file_destroy); | |
154 | } | |
155 | ||
156 | ||
157 | int ttm_base_object_init(struct ttm_object_file *tfile, | |
158 | struct ttm_base_object *base, | |
159 | bool shareable, | |
160 | enum ttm_object_type object_type, | |
161 | void (*refcount_release) (struct ttm_base_object **), | |
162 | void (*ref_obj_release) (struct ttm_base_object *, | |
163 | enum ttm_ref_type ref_type)) | |
164 | { | |
165 | struct ttm_object_device *tdev = tfile->tdev; | |
166 | int ret; | |
167 | ||
168 | base->shareable = shareable; | |
169 | base->tfile = ttm_object_file_ref(tfile); | |
170 | base->refcount_release = refcount_release; | |
171 | base->ref_obj_release = ref_obj_release; | |
172 | base->object_type = object_type; | |
88071539 | 173 | kref_init(&base->refcount); |
5293908a TH |
174 | spin_lock(&tdev->object_lock); |
175 | ret = drm_ht_just_insert_please_rcu(&tdev->object_hash, | |
176 | &base->hash, | |
177 | (unsigned long)base, 31, 0, 0); | |
cdad0521 | 178 | spin_unlock(&tdev->object_lock); |
88071539 TH |
179 | if (unlikely(ret != 0)) |
180 | goto out_err0; | |
181 | ||
fe25deb7 | 182 | ret = ttm_ref_object_add(tfile, base, TTM_REF_USAGE, NULL, false); |
88071539 TH |
183 | if (unlikely(ret != 0)) |
184 | goto out_err1; | |
185 | ||
186 | ttm_base_object_unref(&base); | |
187 | ||
188 | return 0; | |
189 | out_err1: | |
ae8df2ae | 190 | spin_lock(&tdev->object_lock); |
5293908a | 191 | (void)drm_ht_remove_item_rcu(&tdev->object_hash, &base->hash); |
ae8df2ae | 192 | spin_unlock(&tdev->object_lock); |
88071539 TH |
193 | out_err0: |
194 | return ret; | |
195 | } | |
196 | EXPORT_SYMBOL(ttm_base_object_init); | |
197 | ||
198 | static void ttm_release_base(struct kref *kref) | |
199 | { | |
200 | struct ttm_base_object *base = | |
201 | container_of(kref, struct ttm_base_object, refcount); | |
202 | struct ttm_object_device *tdev = base->tfile->tdev; | |
203 | ||
cdad0521 | 204 | spin_lock(&tdev->object_lock); |
5293908a | 205 | (void)drm_ht_remove_item_rcu(&tdev->object_hash, &base->hash); |
cdad0521 | 206 | spin_unlock(&tdev->object_lock); |
5293908a TH |
207 | |
208 | /* | |
209 | * Note: We don't use synchronize_rcu() here because it's far | |
210 | * too slow. It's up to the user to free the object using | |
211 | * call_rcu() or ttm_base_object_kfree(). | |
212 | */ | |
213 | ||
05efb1ab TH |
214 | ttm_object_file_unref(&base->tfile); |
215 | if (base->refcount_release) | |
88071539 | 216 | base->refcount_release(&base); |
88071539 TH |
217 | } |
218 | ||
219 | void ttm_base_object_unref(struct ttm_base_object **p_base) | |
220 | { | |
221 | struct ttm_base_object *base = *p_base; | |
88071539 TH |
222 | |
223 | *p_base = NULL; | |
224 | ||
cdb650a4 | 225 | kref_put(&base->refcount, ttm_release_base); |
88071539 TH |
226 | } |
227 | EXPORT_SYMBOL(ttm_base_object_unref); | |
228 | ||
229 | struct ttm_base_object *ttm_base_object_lookup(struct ttm_object_file *tfile, | |
230 | uint32_t key) | |
231 | { | |
05efb1ab | 232 | struct ttm_base_object *base = NULL; |
88071539 | 233 | struct drm_hash_item *hash; |
05efb1ab | 234 | struct drm_open_hash *ht = &tfile->ref_hash[TTM_REF_USAGE]; |
88071539 TH |
235 | int ret; |
236 | ||
cdad0521 | 237 | rcu_read_lock(); |
05efb1ab | 238 | ret = drm_ht_find_item_rcu(ht, key, &hash); |
88071539 TH |
239 | |
240 | if (likely(ret == 0)) { | |
05efb1ab TH |
241 | base = drm_hash_entry(hash, struct ttm_ref_object, hash)->obj; |
242 | if (!kref_get_unless_zero(&base->refcount)) | |
243 | base = NULL; | |
88071539 | 244 | } |
cdad0521 | 245 | rcu_read_unlock(); |
88071539 | 246 | |
05efb1ab TH |
247 | return base; |
248 | } | |
249 | EXPORT_SYMBOL(ttm_base_object_lookup); | |
88071539 | 250 | |
05efb1ab TH |
251 | struct ttm_base_object * |
252 | ttm_base_object_lookup_for_ref(struct ttm_object_device *tdev, uint32_t key) | |
253 | { | |
254 | struct ttm_base_object *base = NULL; | |
255 | struct drm_hash_item *hash; | |
256 | struct drm_open_hash *ht = &tdev->object_hash; | |
257 | int ret; | |
258 | ||
259 | rcu_read_lock(); | |
260 | ret = drm_ht_find_item_rcu(ht, key, &hash); | |
261 | ||
262 | if (likely(ret == 0)) { | |
263 | base = drm_hash_entry(hash, struct ttm_base_object, hash); | |
264 | if (!kref_get_unless_zero(&base->refcount)) | |
265 | base = NULL; | |
88071539 | 266 | } |
05efb1ab | 267 | rcu_read_unlock(); |
88071539 TH |
268 | |
269 | return base; | |
270 | } | |
05efb1ab | 271 | EXPORT_SYMBOL(ttm_base_object_lookup_for_ref); |
88071539 | 272 | |
0d3215e3 TH |
273 | /** |
274 | * ttm_ref_object_exists - Check whether a caller has a valid ref object | |
275 | * (has opened) a base object. | |
276 | * | |
277 | * @tfile: Pointer to a struct ttm_object_file identifying the caller. | |
278 | * @base: Pointer to a struct base object. | |
279 | * | |
280 | * Checks wether the caller identified by @tfile has put a valid USAGE | |
281 | * reference object on the base object identified by @base. | |
282 | */ | |
283 | bool ttm_ref_object_exists(struct ttm_object_file *tfile, | |
284 | struct ttm_base_object *base) | |
285 | { | |
286 | struct drm_open_hash *ht = &tfile->ref_hash[TTM_REF_USAGE]; | |
287 | struct drm_hash_item *hash; | |
288 | struct ttm_ref_object *ref; | |
289 | ||
290 | rcu_read_lock(); | |
291 | if (unlikely(drm_ht_find_item_rcu(ht, base->hash.key, &hash) != 0)) | |
292 | goto out_false; | |
293 | ||
294 | /* | |
295 | * Verify that the ref object is really pointing to our base object. | |
296 | * Our base object could actually be dead, and the ref object pointing | |
297 | * to another base object with the same handle. | |
298 | */ | |
299 | ref = drm_hash_entry(hash, struct ttm_ref_object, hash); | |
300 | if (unlikely(base != ref->obj)) | |
301 | goto out_false; | |
302 | ||
303 | /* | |
304 | * Verify that the ref->obj pointer was actually valid! | |
305 | */ | |
306 | rmb(); | |
2c935bc5 | 307 | if (unlikely(kref_read(&ref->kref) == 0)) |
0d3215e3 TH |
308 | goto out_false; |
309 | ||
310 | rcu_read_unlock(); | |
311 | return true; | |
312 | ||
313 | out_false: | |
314 | rcu_read_unlock(); | |
315 | return false; | |
316 | } | |
317 | EXPORT_SYMBOL(ttm_ref_object_exists); | |
318 | ||
88071539 TH |
319 | int ttm_ref_object_add(struct ttm_object_file *tfile, |
320 | struct ttm_base_object *base, | |
fe25deb7 TH |
321 | enum ttm_ref_type ref_type, bool *existed, |
322 | bool require_existed) | |
88071539 TH |
323 | { |
324 | struct drm_open_hash *ht = &tfile->ref_hash[ref_type]; | |
325 | struct ttm_ref_object *ref; | |
326 | struct drm_hash_item *hash; | |
327 | struct ttm_mem_global *mem_glob = tfile->tdev->mem_glob; | |
328 | int ret = -EINVAL; | |
329 | ||
05efb1ab TH |
330 | if (base->tfile != tfile && !base->shareable) |
331 | return -EPERM; | |
332 | ||
88071539 TH |
333 | if (existed != NULL) |
334 | *existed = true; | |
335 | ||
336 | while (ret == -EINVAL) { | |
05efb1ab TH |
337 | rcu_read_lock(); |
338 | ret = drm_ht_find_item_rcu(ht, base->hash.key, &hash); | |
88071539 TH |
339 | |
340 | if (ret == 0) { | |
341 | ref = drm_hash_entry(hash, struct ttm_ref_object, hash); | |
c66f8543 | 342 | if (kref_get_unless_zero(&ref->kref)) { |
05efb1ab TH |
343 | rcu_read_unlock(); |
344 | break; | |
345 | } | |
88071539 TH |
346 | } |
347 | ||
05efb1ab | 348 | rcu_read_unlock(); |
fe25deb7 TH |
349 | if (require_existed) |
350 | return -EPERM; | |
351 | ||
88071539 TH |
352 | ret = ttm_mem_global_alloc(mem_glob, sizeof(*ref), |
353 | false, false); | |
354 | if (unlikely(ret != 0)) | |
355 | return ret; | |
356 | ref = kmalloc(sizeof(*ref), GFP_KERNEL); | |
357 | if (unlikely(ref == NULL)) { | |
358 | ttm_mem_global_free(mem_glob, sizeof(*ref)); | |
359 | return -ENOMEM; | |
360 | } | |
361 | ||
362 | ref->hash.key = base->hash.key; | |
363 | ref->obj = base; | |
364 | ref->tfile = tfile; | |
365 | ref->ref_type = ref_type; | |
366 | kref_init(&ref->kref); | |
367 | ||
05efb1ab TH |
368 | spin_lock(&tfile->lock); |
369 | ret = drm_ht_insert_item_rcu(ht, &ref->hash); | |
88071539 TH |
370 | |
371 | if (likely(ret == 0)) { | |
372 | list_add_tail(&ref->head, &tfile->ref_list); | |
373 | kref_get(&base->refcount); | |
05efb1ab | 374 | spin_unlock(&tfile->lock); |
88071539 TH |
375 | if (existed != NULL) |
376 | *existed = false; | |
377 | break; | |
378 | } | |
379 | ||
05efb1ab | 380 | spin_unlock(&tfile->lock); |
88071539 TH |
381 | BUG_ON(ret != -EINVAL); |
382 | ||
383 | ttm_mem_global_free(mem_glob, sizeof(*ref)); | |
384 | kfree(ref); | |
385 | } | |
386 | ||
387 | return ret; | |
388 | } | |
389 | EXPORT_SYMBOL(ttm_ref_object_add); | |
390 | ||
391 | static void ttm_ref_object_release(struct kref *kref) | |
392 | { | |
393 | struct ttm_ref_object *ref = | |
394 | container_of(kref, struct ttm_ref_object, kref); | |
395 | struct ttm_base_object *base = ref->obj; | |
396 | struct ttm_object_file *tfile = ref->tfile; | |
397 | struct drm_open_hash *ht; | |
398 | struct ttm_mem_global *mem_glob = tfile->tdev->mem_glob; | |
399 | ||
400 | ht = &tfile->ref_hash[ref->ref_type]; | |
05efb1ab | 401 | (void)drm_ht_remove_item_rcu(ht, &ref->hash); |
88071539 | 402 | list_del(&ref->head); |
05efb1ab | 403 | spin_unlock(&tfile->lock); |
88071539 TH |
404 | |
405 | if (ref->ref_type != TTM_REF_USAGE && base->ref_obj_release) | |
406 | base->ref_obj_release(base, ref->ref_type); | |
407 | ||
408 | ttm_base_object_unref(&ref->obj); | |
409 | ttm_mem_global_free(mem_glob, sizeof(*ref)); | |
05efb1ab TH |
410 | kfree_rcu(ref, rcu_head); |
411 | spin_lock(&tfile->lock); | |
88071539 TH |
412 | } |
413 | ||
414 | int ttm_ref_object_base_unref(struct ttm_object_file *tfile, | |
415 | unsigned long key, enum ttm_ref_type ref_type) | |
416 | { | |
417 | struct drm_open_hash *ht = &tfile->ref_hash[ref_type]; | |
418 | struct ttm_ref_object *ref; | |
419 | struct drm_hash_item *hash; | |
420 | int ret; | |
421 | ||
05efb1ab | 422 | spin_lock(&tfile->lock); |
88071539 TH |
423 | ret = drm_ht_find_item(ht, key, &hash); |
424 | if (unlikely(ret != 0)) { | |
05efb1ab | 425 | spin_unlock(&tfile->lock); |
88071539 TH |
426 | return -EINVAL; |
427 | } | |
428 | ref = drm_hash_entry(hash, struct ttm_ref_object, hash); | |
429 | kref_put(&ref->kref, ttm_ref_object_release); | |
05efb1ab | 430 | spin_unlock(&tfile->lock); |
88071539 TH |
431 | return 0; |
432 | } | |
433 | EXPORT_SYMBOL(ttm_ref_object_base_unref); | |
434 | ||
435 | void ttm_object_file_release(struct ttm_object_file **p_tfile) | |
436 | { | |
437 | struct ttm_ref_object *ref; | |
438 | struct list_head *list; | |
439 | unsigned int i; | |
440 | struct ttm_object_file *tfile = *p_tfile; | |
441 | ||
442 | *p_tfile = NULL; | |
05efb1ab | 443 | spin_lock(&tfile->lock); |
88071539 TH |
444 | |
445 | /* | |
446 | * Since we release the lock within the loop, we have to | |
447 | * restart it from the beginning each time. | |
448 | */ | |
449 | ||
450 | while (!list_empty(&tfile->ref_list)) { | |
451 | list = tfile->ref_list.next; | |
452 | ref = list_entry(list, struct ttm_ref_object, head); | |
453 | ttm_ref_object_release(&ref->kref); | |
454 | } | |
455 | ||
3ce7803c | 456 | spin_unlock(&tfile->lock); |
88071539 TH |
457 | for (i = 0; i < TTM_REF_NUM; ++i) |
458 | drm_ht_remove(&tfile->ref_hash[i]); | |
459 | ||
88071539 TH |
460 | ttm_object_file_unref(&tfile); |
461 | } | |
462 | EXPORT_SYMBOL(ttm_object_file_release); | |
463 | ||
464 | struct ttm_object_file *ttm_object_file_init(struct ttm_object_device *tdev, | |
465 | unsigned int hash_order) | |
466 | { | |
467 | struct ttm_object_file *tfile = kmalloc(sizeof(*tfile), GFP_KERNEL); | |
468 | unsigned int i; | |
469 | unsigned int j = 0; | |
470 | int ret; | |
471 | ||
472 | if (unlikely(tfile == NULL)) | |
473 | return NULL; | |
474 | ||
05efb1ab | 475 | spin_lock_init(&tfile->lock); |
88071539 TH |
476 | tfile->tdev = tdev; |
477 | kref_init(&tfile->refcount); | |
478 | INIT_LIST_HEAD(&tfile->ref_list); | |
479 | ||
480 | for (i = 0; i < TTM_REF_NUM; ++i) { | |
481 | ret = drm_ht_create(&tfile->ref_hash[i], hash_order); | |
482 | if (ret) { | |
483 | j = i; | |
484 | goto out_err; | |
485 | } | |
486 | } | |
487 | ||
488 | return tfile; | |
489 | out_err: | |
490 | for (i = 0; i < j; ++i) | |
491 | drm_ht_remove(&tfile->ref_hash[i]); | |
492 | ||
493 | kfree(tfile); | |
494 | ||
495 | return NULL; | |
496 | } | |
497 | EXPORT_SYMBOL(ttm_object_file_init); | |
498 | ||
65981f76 TH |
499 | struct ttm_object_device * |
500 | ttm_object_device_init(struct ttm_mem_global *mem_glob, | |
501 | unsigned int hash_order, | |
502 | const struct dma_buf_ops *ops) | |
88071539 TH |
503 | { |
504 | struct ttm_object_device *tdev = kmalloc(sizeof(*tdev), GFP_KERNEL); | |
505 | int ret; | |
506 | ||
507 | if (unlikely(tdev == NULL)) | |
508 | return NULL; | |
509 | ||
510 | tdev->mem_glob = mem_glob; | |
cdad0521 | 511 | spin_lock_init(&tdev->object_lock); |
88071539 TH |
512 | atomic_set(&tdev->object_count, 0); |
513 | ret = drm_ht_create(&tdev->object_hash, hash_order); | |
65981f76 TH |
514 | if (ret != 0) |
515 | goto out_no_object_hash; | |
88071539 | 516 | |
65981f76 TH |
517 | tdev->ops = *ops; |
518 | tdev->dmabuf_release = tdev->ops.release; | |
519 | tdev->ops.release = ttm_prime_dmabuf_release; | |
520 | tdev->dma_buf_size = ttm_round_pot(sizeof(struct dma_buf)) + | |
521 | ttm_round_pot(sizeof(struct file)); | |
522 | return tdev; | |
88071539 | 523 | |
65981f76 | 524 | out_no_object_hash: |
88071539 TH |
525 | kfree(tdev); |
526 | return NULL; | |
527 | } | |
528 | EXPORT_SYMBOL(ttm_object_device_init); | |
529 | ||
530 | void ttm_object_device_release(struct ttm_object_device **p_tdev) | |
531 | { | |
532 | struct ttm_object_device *tdev = *p_tdev; | |
533 | ||
534 | *p_tdev = NULL; | |
535 | ||
88071539 | 536 | drm_ht_remove(&tdev->object_hash); |
88071539 TH |
537 | |
538 | kfree(tdev); | |
539 | } | |
540 | EXPORT_SYMBOL(ttm_object_device_release); | |
65981f76 TH |
541 | |
542 | /** | |
543 | * get_dma_buf_unless_doomed - get a dma_buf reference if possible. | |
544 | * | |
545 | * @dma_buf: Non-refcounted pointer to a struct dma-buf. | |
546 | * | |
547 | * Obtain a file reference from a lookup structure that doesn't refcount | |
548 | * the file, but synchronizes with its release method to make sure it has | |
549 | * not been freed yet. See for example kref_get_unless_zero documentation. | |
550 | * Returns true if refcounting succeeds, false otherwise. | |
551 | * | |
552 | * Nobody really wants this as a public API yet, so let it mature here | |
553 | * for some time... | |
554 | */ | |
555 | static bool __must_check get_dma_buf_unless_doomed(struct dma_buf *dmabuf) | |
556 | { | |
557 | return atomic_long_inc_not_zero(&dmabuf->file->f_count) != 0L; | |
558 | } | |
559 | ||
560 | /** | |
561 | * ttm_prime_refcount_release - refcount release method for a prime object. | |
562 | * | |
563 | * @p_base: Pointer to ttm_base_object pointer. | |
564 | * | |
565 | * This is a wrapper that calls the refcount_release founction of the | |
566 | * underlying object. At the same time it cleans up the prime object. | |
567 | * This function is called when all references to the base object we | |
568 | * derive from are gone. | |
569 | */ | |
570 | static void ttm_prime_refcount_release(struct ttm_base_object **p_base) | |
571 | { | |
572 | struct ttm_base_object *base = *p_base; | |
573 | struct ttm_prime_object *prime; | |
574 | ||
575 | *p_base = NULL; | |
576 | prime = container_of(base, struct ttm_prime_object, base); | |
577 | BUG_ON(prime->dma_buf != NULL); | |
578 | mutex_destroy(&prime->mutex); | |
579 | if (prime->refcount_release) | |
580 | prime->refcount_release(&base); | |
581 | } | |
582 | ||
583 | /** | |
584 | * ttm_prime_dmabuf_release - Release method for the dma-bufs we export | |
585 | * | |
586 | * @dma_buf: | |
587 | * | |
588 | * This function first calls the dma_buf release method the driver | |
589 | * provides. Then it cleans up our dma_buf pointer used for lookup, | |
590 | * and finally releases the reference the dma_buf has on our base | |
591 | * object. | |
592 | */ | |
593 | static void ttm_prime_dmabuf_release(struct dma_buf *dma_buf) | |
594 | { | |
595 | struct ttm_prime_object *prime = | |
596 | (struct ttm_prime_object *) dma_buf->priv; | |
597 | struct ttm_base_object *base = &prime->base; | |
598 | struct ttm_object_device *tdev = base->tfile->tdev; | |
599 | ||
600 | if (tdev->dmabuf_release) | |
601 | tdev->dmabuf_release(dma_buf); | |
602 | mutex_lock(&prime->mutex); | |
603 | if (prime->dma_buf == dma_buf) | |
604 | prime->dma_buf = NULL; | |
605 | mutex_unlock(&prime->mutex); | |
606 | ttm_mem_global_free(tdev->mem_glob, tdev->dma_buf_size); | |
607 | ttm_base_object_unref(&base); | |
608 | } | |
609 | ||
610 | /** | |
611 | * ttm_prime_fd_to_handle - Get a base object handle from a prime fd | |
612 | * | |
613 | * @tfile: A struct ttm_object_file identifying the caller. | |
614 | * @fd: The prime / dmabuf fd. | |
615 | * @handle: The returned handle. | |
616 | * | |
617 | * This function returns a handle to an object that previously exported | |
618 | * a dma-buf. Note that we don't handle imports yet, because we simply | |
619 | * have no consumers of that implementation. | |
620 | */ | |
621 | int ttm_prime_fd_to_handle(struct ttm_object_file *tfile, | |
622 | int fd, u32 *handle) | |
623 | { | |
624 | struct ttm_object_device *tdev = tfile->tdev; | |
625 | struct dma_buf *dma_buf; | |
626 | struct ttm_prime_object *prime; | |
627 | struct ttm_base_object *base; | |
628 | int ret; | |
629 | ||
630 | dma_buf = dma_buf_get(fd); | |
631 | if (IS_ERR(dma_buf)) | |
632 | return PTR_ERR(dma_buf); | |
633 | ||
634 | if (dma_buf->ops != &tdev->ops) | |
635 | return -ENOSYS; | |
636 | ||
637 | prime = (struct ttm_prime_object *) dma_buf->priv; | |
638 | base = &prime->base; | |
639 | *handle = base->hash.key; | |
fe25deb7 | 640 | ret = ttm_ref_object_add(tfile, base, TTM_REF_USAGE, NULL, false); |
65981f76 TH |
641 | |
642 | dma_buf_put(dma_buf); | |
643 | ||
644 | return ret; | |
645 | } | |
646 | EXPORT_SYMBOL_GPL(ttm_prime_fd_to_handle); | |
647 | ||
648 | /** | |
649 | * ttm_prime_handle_to_fd - Return a dma_buf fd from a ttm prime object | |
650 | * | |
651 | * @tfile: Struct ttm_object_file identifying the caller. | |
652 | * @handle: Handle to the object we're exporting from. | |
653 | * @flags: flags for dma-buf creation. We just pass them on. | |
654 | * @prime_fd: The returned file descriptor. | |
655 | * | |
656 | */ | |
657 | int ttm_prime_handle_to_fd(struct ttm_object_file *tfile, | |
658 | uint32_t handle, uint32_t flags, | |
659 | int *prime_fd) | |
660 | { | |
661 | struct ttm_object_device *tdev = tfile->tdev; | |
662 | struct ttm_base_object *base; | |
663 | struct dma_buf *dma_buf; | |
664 | struct ttm_prime_object *prime; | |
665 | int ret; | |
666 | ||
667 | base = ttm_base_object_lookup(tfile, handle); | |
668 | if (unlikely(base == NULL || | |
669 | base->object_type != ttm_prime_type)) { | |
670 | ret = -ENOENT; | |
671 | goto out_unref; | |
672 | } | |
673 | ||
674 | prime = container_of(base, struct ttm_prime_object, base); | |
675 | if (unlikely(!base->shareable)) { | |
676 | ret = -EPERM; | |
677 | goto out_unref; | |
678 | } | |
679 | ||
680 | ret = mutex_lock_interruptible(&prime->mutex); | |
681 | if (unlikely(ret != 0)) { | |
682 | ret = -ERESTARTSYS; | |
683 | goto out_unref; | |
684 | } | |
685 | ||
686 | dma_buf = prime->dma_buf; | |
687 | if (!dma_buf || !get_dma_buf_unless_doomed(dma_buf)) { | |
d8fbe341 SS |
688 | DEFINE_DMA_BUF_EXPORT_INFO(exp_info); |
689 | ||
690 | exp_info.ops = &tdev->ops; | |
691 | exp_info.size = prime->size; | |
692 | exp_info.flags = flags; | |
693 | exp_info.priv = prime; | |
65981f76 TH |
694 | |
695 | /* | |
696 | * Need to create a new dma_buf, with memory accounting. | |
697 | */ | |
698 | ret = ttm_mem_global_alloc(tdev->mem_glob, tdev->dma_buf_size, | |
699 | false, true); | |
700 | if (unlikely(ret != 0)) { | |
701 | mutex_unlock(&prime->mutex); | |
702 | goto out_unref; | |
703 | } | |
704 | ||
d8fbe341 | 705 | dma_buf = dma_buf_export(&exp_info); |
65981f76 TH |
706 | if (IS_ERR(dma_buf)) { |
707 | ret = PTR_ERR(dma_buf); | |
708 | ttm_mem_global_free(tdev->mem_glob, | |
709 | tdev->dma_buf_size); | |
710 | mutex_unlock(&prime->mutex); | |
711 | goto out_unref; | |
712 | } | |
713 | ||
714 | /* | |
715 | * dma_buf has taken the base object reference | |
716 | */ | |
717 | base = NULL; | |
718 | prime->dma_buf = dma_buf; | |
719 | } | |
720 | mutex_unlock(&prime->mutex); | |
721 | ||
722 | ret = dma_buf_fd(dma_buf, flags); | |
723 | if (ret >= 0) { | |
724 | *prime_fd = ret; | |
725 | ret = 0; | |
726 | } else | |
727 | dma_buf_put(dma_buf); | |
728 | ||
729 | out_unref: | |
730 | if (base) | |
731 | ttm_base_object_unref(&base); | |
732 | return ret; | |
733 | } | |
734 | EXPORT_SYMBOL_GPL(ttm_prime_handle_to_fd); | |
735 | ||
736 | /** | |
737 | * ttm_prime_object_init - Initialize a ttm_prime_object | |
738 | * | |
739 | * @tfile: struct ttm_object_file identifying the caller | |
740 | * @size: The size of the dma_bufs we export. | |
741 | * @prime: The object to be initialized. | |
742 | * @shareable: See ttm_base_object_init | |
743 | * @type: See ttm_base_object_init | |
744 | * @refcount_release: See ttm_base_object_init | |
745 | * @ref_obj_release: See ttm_base_object_init | |
746 | * | |
747 | * Initializes an object which is compatible with the drm_prime model | |
748 | * for data sharing between processes and devices. | |
749 | */ | |
750 | int ttm_prime_object_init(struct ttm_object_file *tfile, size_t size, | |
751 | struct ttm_prime_object *prime, bool shareable, | |
752 | enum ttm_object_type type, | |
753 | void (*refcount_release) (struct ttm_base_object **), | |
754 | void (*ref_obj_release) (struct ttm_base_object *, | |
755 | enum ttm_ref_type ref_type)) | |
756 | { | |
757 | mutex_init(&prime->mutex); | |
758 | prime->size = PAGE_ALIGN(size); | |
759 | prime->real_type = type; | |
760 | prime->dma_buf = NULL; | |
761 | prime->refcount_release = refcount_release; | |
762 | return ttm_base_object_init(tfile, &prime->base, shareable, | |
763 | ttm_prime_type, | |
764 | ttm_prime_refcount_release, | |
765 | ref_obj_release); | |
766 | } | |
767 | EXPORT_SYMBOL(ttm_prime_object_init); |