xref: /openbmc/linux/drivers/gpu/drm/ttm/ttm_bo.c (revision a20eefae)
1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2 /**************************************************************************
3  *
4  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
5  * All Rights Reserved.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sub license, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * The above copyright notice and this permission notice (including the
16  * next paragraph) shall be included in all copies or substantial portions
17  * of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25  * USE OR OTHER DEALINGS IN THE SOFTWARE.
26  *
27  **************************************************************************/
28 /*
29  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
30  */
31 
32 #define pr_fmt(fmt) "[TTM] " fmt
33 
34 #include <drm/ttm/ttm_module.h>
35 #include <drm/ttm/ttm_bo_driver.h>
36 #include <drm/ttm/ttm_placement.h>
37 #include <linux/jiffies.h>
38 #include <linux/slab.h>
39 #include <linux/sched.h>
40 #include <linux/mm.h>
41 #include <linux/file.h>
42 #include <linux/module.h>
43 #include <linux/atomic.h>
44 #include <linux/reservation.h>
45 
46 static void ttm_bo_global_kobj_release(struct kobject *kobj);
47 
48 /**
49  * ttm_global_mutex - protecting the global BO state
50  */
51 DEFINE_MUTEX(ttm_global_mutex);
52 unsigned ttm_bo_glob_use_count;
53 struct ttm_bo_global ttm_bo_glob;
54 
55 static struct attribute ttm_bo_count = {
56 	.name = "bo_count",
57 	.mode = S_IRUGO
58 };
59 
60 /* default destructor */
61 static void ttm_bo_default_destroy(struct ttm_buffer_object *bo)
62 {
63 	kfree(bo);
64 }
65 
66 static inline int ttm_mem_type_from_place(const struct ttm_place *place,
67 					  uint32_t *mem_type)
68 {
69 	int pos;
70 
71 	pos = ffs(place->flags & TTM_PL_MASK_MEM);
72 	if (unlikely(!pos))
73 		return -EINVAL;
74 
75 	*mem_type = pos - 1;
76 	return 0;
77 }
78 
79 static void ttm_mem_type_debug(struct ttm_bo_device *bdev, struct drm_printer *p,
80 			       int mem_type)
81 {
82 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
83 
84 	drm_printf(p, "    has_type: %d\n", man->has_type);
85 	drm_printf(p, "    use_type: %d\n", man->use_type);
86 	drm_printf(p, "    flags: 0x%08X\n", man->flags);
87 	drm_printf(p, "    gpu_offset: 0x%08llX\n", man->gpu_offset);
88 	drm_printf(p, "    size: %llu\n", man->size);
89 	drm_printf(p, "    available_caching: 0x%08X\n", man->available_caching);
90 	drm_printf(p, "    default_caching: 0x%08X\n", man->default_caching);
91 	if (mem_type != TTM_PL_SYSTEM)
92 		(*man->func->debug)(man, p);
93 }
94 
95 static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
96 					struct ttm_placement *placement)
97 {
98 	struct drm_printer p = drm_debug_printer(TTM_PFX);
99 	int i, ret, mem_type;
100 
101 	drm_printf(&p, "No space for %p (%lu pages, %luK, %luM)\n",
102 		   bo, bo->mem.num_pages, bo->mem.size >> 10,
103 		   bo->mem.size >> 20);
104 	for (i = 0; i < placement->num_placement; i++) {
105 		ret = ttm_mem_type_from_place(&placement->placement[i],
106 						&mem_type);
107 		if (ret)
108 			return;
109 		drm_printf(&p, "  placement[%d]=0x%08X (%d)\n",
110 			   i, placement->placement[i].flags, mem_type);
111 		ttm_mem_type_debug(bo->bdev, &p, mem_type);
112 	}
113 }
114 
115 static ssize_t ttm_bo_global_show(struct kobject *kobj,
116 				  struct attribute *attr,
117 				  char *buffer)
118 {
119 	struct ttm_bo_global *glob =
120 		container_of(kobj, struct ttm_bo_global, kobj);
121 
122 	return snprintf(buffer, PAGE_SIZE, "%d\n",
123 				atomic_read(&glob->bo_count));
124 }
125 
126 static struct attribute *ttm_bo_global_attrs[] = {
127 	&ttm_bo_count,
128 	NULL
129 };
130 
131 static const struct sysfs_ops ttm_bo_global_ops = {
132 	.show = &ttm_bo_global_show
133 };
134 
135 static struct kobj_type ttm_bo_glob_kobj_type  = {
136 	.release = &ttm_bo_global_kobj_release,
137 	.sysfs_ops = &ttm_bo_global_ops,
138 	.default_attrs = ttm_bo_global_attrs
139 };
140 
141 
142 static inline uint32_t ttm_bo_type_flags(unsigned type)
143 {
144 	return 1 << (type);
145 }
146 
147 static void ttm_bo_release_list(struct kref *list_kref)
148 {
149 	struct ttm_buffer_object *bo =
150 	    container_of(list_kref, struct ttm_buffer_object, list_kref);
151 	struct ttm_bo_device *bdev = bo->bdev;
152 	size_t acc_size = bo->acc_size;
153 
154 	BUG_ON(kref_read(&bo->list_kref));
155 	BUG_ON(kref_read(&bo->kref));
156 	BUG_ON(atomic_read(&bo->cpu_writers));
157 	BUG_ON(bo->mem.mm_node != NULL);
158 	BUG_ON(!list_empty(&bo->lru));
159 	BUG_ON(!list_empty(&bo->ddestroy));
160 	ttm_tt_destroy(bo->ttm);
161 	atomic_dec(&bo->bdev->glob->bo_count);
162 	dma_fence_put(bo->moving);
163 	reservation_object_fini(&bo->ttm_resv);
164 	mutex_destroy(&bo->wu_mutex);
165 	bo->destroy(bo);
166 	ttm_mem_global_free(bdev->glob->mem_glob, acc_size);
167 }
168 
169 static void ttm_bo_add_mem_to_lru(struct ttm_buffer_object *bo,
170 				  struct ttm_mem_reg *mem)
171 {
172 	struct ttm_bo_device *bdev = bo->bdev;
173 	struct ttm_mem_type_manager *man;
174 
175 	reservation_object_assert_held(bo->resv);
176 
177 	if (!list_empty(&bo->lru))
178 		return;
179 
180 	if (mem->placement & TTM_PL_FLAG_NO_EVICT)
181 		return;
182 
183 	man = &bdev->man[mem->mem_type];
184 	list_add_tail(&bo->lru, &man->lru[bo->priority]);
185 	kref_get(&bo->list_kref);
186 
187 	if (bo->ttm && !(bo->ttm->page_flags &
188 			 (TTM_PAGE_FLAG_SG | TTM_PAGE_FLAG_SWAPPED))) {
189 		list_add_tail(&bo->swap, &bdev->glob->swap_lru[bo->priority]);
190 		kref_get(&bo->list_kref);
191 	}
192 }
193 
194 void ttm_bo_add_to_lru(struct ttm_buffer_object *bo)
195 {
196 	ttm_bo_add_mem_to_lru(bo, &bo->mem);
197 }
198 EXPORT_SYMBOL(ttm_bo_add_to_lru);
199 
200 static void ttm_bo_ref_bug(struct kref *list_kref)
201 {
202 	BUG();
203 }
204 
205 void ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
206 {
207 	struct ttm_bo_device *bdev = bo->bdev;
208 	bool notify = false;
209 
210 	if (!list_empty(&bo->swap)) {
211 		list_del_init(&bo->swap);
212 		kref_put(&bo->list_kref, ttm_bo_ref_bug);
213 		notify = true;
214 	}
215 	if (!list_empty(&bo->lru)) {
216 		list_del_init(&bo->lru);
217 		kref_put(&bo->list_kref, ttm_bo_ref_bug);
218 		notify = true;
219 	}
220 
221 	if (notify && bdev->driver->del_from_lru_notify)
222 		bdev->driver->del_from_lru_notify(bo);
223 }
224 
225 void ttm_bo_del_sub_from_lru(struct ttm_buffer_object *bo)
226 {
227 	struct ttm_bo_global *glob = bo->bdev->glob;
228 
229 	spin_lock(&glob->lru_lock);
230 	ttm_bo_del_from_lru(bo);
231 	spin_unlock(&glob->lru_lock);
232 }
233 EXPORT_SYMBOL(ttm_bo_del_sub_from_lru);
234 
235 static void ttm_bo_bulk_move_set_pos(struct ttm_lru_bulk_move_pos *pos,
236 				     struct ttm_buffer_object *bo)
237 {
238 	if (!pos->first)
239 		pos->first = bo;
240 	pos->last = bo;
241 }
242 
243 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
244 			     struct ttm_lru_bulk_move *bulk)
245 {
246 	reservation_object_assert_held(bo->resv);
247 
248 	ttm_bo_del_from_lru(bo);
249 	ttm_bo_add_to_lru(bo);
250 
251 	if (bulk && !(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
252 		switch (bo->mem.mem_type) {
253 		case TTM_PL_TT:
254 			ttm_bo_bulk_move_set_pos(&bulk->tt[bo->priority], bo);
255 			break;
256 
257 		case TTM_PL_VRAM:
258 			ttm_bo_bulk_move_set_pos(&bulk->vram[bo->priority], bo);
259 			break;
260 		}
261 		if (bo->ttm && !(bo->ttm->page_flags &
262 				 (TTM_PAGE_FLAG_SG | TTM_PAGE_FLAG_SWAPPED)))
263 			ttm_bo_bulk_move_set_pos(&bulk->swap[bo->priority], bo);
264 	}
265 }
266 EXPORT_SYMBOL(ttm_bo_move_to_lru_tail);
267 
268 void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk)
269 {
270 	unsigned i;
271 
272 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
273 		struct ttm_lru_bulk_move_pos *pos = &bulk->tt[i];
274 		struct ttm_mem_type_manager *man;
275 
276 		if (!pos->first)
277 			continue;
278 
279 		reservation_object_assert_held(pos->first->resv);
280 		reservation_object_assert_held(pos->last->resv);
281 
282 		man = &pos->first->bdev->man[TTM_PL_TT];
283 		list_bulk_move_tail(&man->lru[i], &pos->first->lru,
284 				    &pos->last->lru);
285 	}
286 
287 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
288 		struct ttm_lru_bulk_move_pos *pos = &bulk->vram[i];
289 		struct ttm_mem_type_manager *man;
290 
291 		if (!pos->first)
292 			continue;
293 
294 		reservation_object_assert_held(pos->first->resv);
295 		reservation_object_assert_held(pos->last->resv);
296 
297 		man = &pos->first->bdev->man[TTM_PL_VRAM];
298 		list_bulk_move_tail(&man->lru[i], &pos->first->lru,
299 				    &pos->last->lru);
300 	}
301 
302 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
303 		struct ttm_lru_bulk_move_pos *pos = &bulk->swap[i];
304 		struct list_head *lru;
305 
306 		if (!pos->first)
307 			continue;
308 
309 		reservation_object_assert_held(pos->first->resv);
310 		reservation_object_assert_held(pos->last->resv);
311 
312 		lru = &pos->first->bdev->glob->swap_lru[i];
313 		list_bulk_move_tail(lru, &pos->first->swap, &pos->last->swap);
314 	}
315 }
316 EXPORT_SYMBOL(ttm_bo_bulk_move_lru_tail);
317 
318 static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
319 				  struct ttm_mem_reg *mem, bool evict,
320 				  struct ttm_operation_ctx *ctx)
321 {
322 	struct ttm_bo_device *bdev = bo->bdev;
323 	bool old_is_pci = ttm_mem_reg_is_pci(bdev, &bo->mem);
324 	bool new_is_pci = ttm_mem_reg_is_pci(bdev, mem);
325 	struct ttm_mem_type_manager *old_man = &bdev->man[bo->mem.mem_type];
326 	struct ttm_mem_type_manager *new_man = &bdev->man[mem->mem_type];
327 	int ret = 0;
328 
329 	if (old_is_pci || new_is_pci ||
330 	    ((mem->placement & bo->mem.placement & TTM_PL_MASK_CACHING) == 0)) {
331 		ret = ttm_mem_io_lock(old_man, true);
332 		if (unlikely(ret != 0))
333 			goto out_err;
334 		ttm_bo_unmap_virtual_locked(bo);
335 		ttm_mem_io_unlock(old_man);
336 	}
337 
338 	/*
339 	 * Create and bind a ttm if required.
340 	 */
341 
342 	if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
343 		if (bo->ttm == NULL) {
344 			bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);
345 			ret = ttm_tt_create(bo, zero);
346 			if (ret)
347 				goto out_err;
348 		}
349 
350 		ret = ttm_tt_set_placement_caching(bo->ttm, mem->placement);
351 		if (ret)
352 			goto out_err;
353 
354 		if (mem->mem_type != TTM_PL_SYSTEM) {
355 			ret = ttm_tt_bind(bo->ttm, mem, ctx);
356 			if (ret)
357 				goto out_err;
358 		}
359 
360 		if (bo->mem.mem_type == TTM_PL_SYSTEM) {
361 			if (bdev->driver->move_notify)
362 				bdev->driver->move_notify(bo, evict, mem);
363 			bo->mem = *mem;
364 			mem->mm_node = NULL;
365 			goto moved;
366 		}
367 	}
368 
369 	if (bdev->driver->move_notify)
370 		bdev->driver->move_notify(bo, evict, mem);
371 
372 	if (!(old_man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
373 	    !(new_man->flags & TTM_MEMTYPE_FLAG_FIXED))
374 		ret = ttm_bo_move_ttm(bo, ctx, mem);
375 	else if (bdev->driver->move)
376 		ret = bdev->driver->move(bo, evict, ctx, mem);
377 	else
378 		ret = ttm_bo_move_memcpy(bo, ctx, mem);
379 
380 	if (ret) {
381 		if (bdev->driver->move_notify) {
382 			swap(*mem, bo->mem);
383 			bdev->driver->move_notify(bo, false, mem);
384 			swap(*mem, bo->mem);
385 		}
386 
387 		goto out_err;
388 	}
389 
390 moved:
391 	if (bo->evicted) {
392 		if (bdev->driver->invalidate_caches) {
393 			ret = bdev->driver->invalidate_caches(bdev, bo->mem.placement);
394 			if (ret)
395 				pr_err("Can not flush read caches\n");
396 		}
397 		bo->evicted = false;
398 	}
399 
400 	if (bo->mem.mm_node)
401 		bo->offset = (bo->mem.start << PAGE_SHIFT) +
402 		    bdev->man[bo->mem.mem_type].gpu_offset;
403 	else
404 		bo->offset = 0;
405 
406 	ctx->bytes_moved += bo->num_pages << PAGE_SHIFT;
407 	return 0;
408 
409 out_err:
410 	new_man = &bdev->man[bo->mem.mem_type];
411 	if (new_man->flags & TTM_MEMTYPE_FLAG_FIXED) {
412 		ttm_tt_destroy(bo->ttm);
413 		bo->ttm = NULL;
414 	}
415 
416 	return ret;
417 }
418 
419 /**
420  * Call bo::reserved.
421  * Will release GPU memory type usage on destruction.
422  * This is the place to put in driver specific hooks to release
423  * driver private resources.
424  * Will release the bo::reserved lock.
425  */
426 
427 static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)
428 {
429 	if (bo->bdev->driver->move_notify)
430 		bo->bdev->driver->move_notify(bo, false, NULL);
431 
432 	ttm_tt_destroy(bo->ttm);
433 	bo->ttm = NULL;
434 	ttm_bo_mem_put(bo, &bo->mem);
435 }
436 
437 static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo)
438 {
439 	int r;
440 
441 	if (bo->resv == &bo->ttm_resv)
442 		return 0;
443 
444 	BUG_ON(!reservation_object_trylock(&bo->ttm_resv));
445 
446 	r = reservation_object_copy_fences(&bo->ttm_resv, bo->resv);
447 	if (r)
448 		reservation_object_unlock(&bo->ttm_resv);
449 
450 	return r;
451 }
452 
453 static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo)
454 {
455 	struct reservation_object_list *fobj;
456 	struct dma_fence *fence;
457 	int i;
458 
459 	fobj = reservation_object_get_list(&bo->ttm_resv);
460 	fence = reservation_object_get_excl(&bo->ttm_resv);
461 	if (fence && !fence->ops->signaled)
462 		dma_fence_enable_sw_signaling(fence);
463 
464 	for (i = 0; fobj && i < fobj->shared_count; ++i) {
465 		fence = rcu_dereference_protected(fobj->shared[i],
466 					reservation_object_held(bo->resv));
467 
468 		if (!fence->ops->signaled)
469 			dma_fence_enable_sw_signaling(fence);
470 	}
471 }
472 
473 static void ttm_bo_cleanup_refs_or_queue(struct ttm_buffer_object *bo)
474 {
475 	struct ttm_bo_device *bdev = bo->bdev;
476 	struct ttm_bo_global *glob = bdev->glob;
477 	int ret;
478 
479 	ret = ttm_bo_individualize_resv(bo);
480 	if (ret) {
481 		/* Last resort, if we fail to allocate memory for the
482 		 * fences block for the BO to become idle
483 		 */
484 		reservation_object_wait_timeout_rcu(bo->resv, true, false,
485 						    30 * HZ);
486 		spin_lock(&glob->lru_lock);
487 		goto error;
488 	}
489 
490 	spin_lock(&glob->lru_lock);
491 	ret = reservation_object_trylock(bo->resv) ? 0 : -EBUSY;
492 	if (!ret) {
493 		if (reservation_object_test_signaled_rcu(&bo->ttm_resv, true)) {
494 			ttm_bo_del_from_lru(bo);
495 			spin_unlock(&glob->lru_lock);
496 			if (bo->resv != &bo->ttm_resv)
497 				reservation_object_unlock(&bo->ttm_resv);
498 
499 			ttm_bo_cleanup_memtype_use(bo);
500 			reservation_object_unlock(bo->resv);
501 			return;
502 		}
503 
504 		ttm_bo_flush_all_fences(bo);
505 
506 		/*
507 		 * Make NO_EVICT bos immediately available to
508 		 * shrinkers, now that they are queued for
509 		 * destruction.
510 		 */
511 		if (bo->mem.placement & TTM_PL_FLAG_NO_EVICT) {
512 			bo->mem.placement &= ~TTM_PL_FLAG_NO_EVICT;
513 			ttm_bo_add_to_lru(bo);
514 		}
515 
516 		reservation_object_unlock(bo->resv);
517 	}
518 	if (bo->resv != &bo->ttm_resv)
519 		reservation_object_unlock(&bo->ttm_resv);
520 
521 error:
522 	kref_get(&bo->list_kref);
523 	list_add_tail(&bo->ddestroy, &bdev->ddestroy);
524 	spin_unlock(&glob->lru_lock);
525 
526 	schedule_delayed_work(&bdev->wq,
527 			      ((HZ / 100) < 1) ? 1 : HZ / 100);
528 }
529 
530 /**
531  * function ttm_bo_cleanup_refs
532  * If bo idle, remove from delayed- and lru lists, and unref.
533  * If not idle, do nothing.
534  *
535  * Must be called with lru_lock and reservation held, this function
536  * will drop the lru lock and optionally the reservation lock before returning.
537  *
538  * @interruptible         Any sleeps should occur interruptibly.
539  * @no_wait_gpu           Never wait for gpu. Return -EBUSY instead.
540  * @unlock_resv           Unlock the reservation lock as well.
541  */
542 
543 static int ttm_bo_cleanup_refs(struct ttm_buffer_object *bo,
544 			       bool interruptible, bool no_wait_gpu,
545 			       bool unlock_resv)
546 {
547 	struct ttm_bo_global *glob = bo->bdev->glob;
548 	struct reservation_object *resv;
549 	int ret;
550 
551 	if (unlikely(list_empty(&bo->ddestroy)))
552 		resv = bo->resv;
553 	else
554 		resv = &bo->ttm_resv;
555 
556 	if (reservation_object_test_signaled_rcu(resv, true))
557 		ret = 0;
558 	else
559 		ret = -EBUSY;
560 
561 	if (ret && !no_wait_gpu) {
562 		long lret;
563 
564 		if (unlock_resv)
565 			reservation_object_unlock(bo->resv);
566 		spin_unlock(&glob->lru_lock);
567 
568 		lret = reservation_object_wait_timeout_rcu(resv, true,
569 							   interruptible,
570 							   30 * HZ);
571 
572 		if (lret < 0)
573 			return lret;
574 		else if (lret == 0)
575 			return -EBUSY;
576 
577 		spin_lock(&glob->lru_lock);
578 		if (unlock_resv && !reservation_object_trylock(bo->resv)) {
579 			/*
580 			 * We raced, and lost, someone else holds the reservation now,
581 			 * and is probably busy in ttm_bo_cleanup_memtype_use.
582 			 *
583 			 * Even if it's not the case, because we finished waiting any
584 			 * delayed destruction would succeed, so just return success
585 			 * here.
586 			 */
587 			spin_unlock(&glob->lru_lock);
588 			return 0;
589 		}
590 		ret = 0;
591 	}
592 
593 	if (ret || unlikely(list_empty(&bo->ddestroy))) {
594 		if (unlock_resv)
595 			reservation_object_unlock(bo->resv);
596 		spin_unlock(&glob->lru_lock);
597 		return ret;
598 	}
599 
600 	ttm_bo_del_from_lru(bo);
601 	list_del_init(&bo->ddestroy);
602 	kref_put(&bo->list_kref, ttm_bo_ref_bug);
603 
604 	spin_unlock(&glob->lru_lock);
605 	ttm_bo_cleanup_memtype_use(bo);
606 
607 	if (unlock_resv)
608 		reservation_object_unlock(bo->resv);
609 
610 	return 0;
611 }
612 
613 /**
614  * Traverse the delayed list, and call ttm_bo_cleanup_refs on all
615  * encountered buffers.
616  */
617 static bool ttm_bo_delayed_delete(struct ttm_bo_device *bdev, bool remove_all)
618 {
619 	struct ttm_bo_global *glob = bdev->glob;
620 	struct list_head removed;
621 	bool empty;
622 
623 	INIT_LIST_HEAD(&removed);
624 
625 	spin_lock(&glob->lru_lock);
626 	while (!list_empty(&bdev->ddestroy)) {
627 		struct ttm_buffer_object *bo;
628 
629 		bo = list_first_entry(&bdev->ddestroy, struct ttm_buffer_object,
630 				      ddestroy);
631 		kref_get(&bo->list_kref);
632 		list_move_tail(&bo->ddestroy, &removed);
633 
634 		if (remove_all || bo->resv != &bo->ttm_resv) {
635 			spin_unlock(&glob->lru_lock);
636 			reservation_object_lock(bo->resv, NULL);
637 
638 			spin_lock(&glob->lru_lock);
639 			ttm_bo_cleanup_refs(bo, false, !remove_all, true);
640 
641 		} else if (reservation_object_trylock(bo->resv)) {
642 			ttm_bo_cleanup_refs(bo, false, !remove_all, true);
643 		} else {
644 			spin_unlock(&glob->lru_lock);
645 		}
646 
647 		kref_put(&bo->list_kref, ttm_bo_release_list);
648 		spin_lock(&glob->lru_lock);
649 	}
650 	list_splice_tail(&removed, &bdev->ddestroy);
651 	empty = list_empty(&bdev->ddestroy);
652 	spin_unlock(&glob->lru_lock);
653 
654 	return empty;
655 }
656 
657 static void ttm_bo_delayed_workqueue(struct work_struct *work)
658 {
659 	struct ttm_bo_device *bdev =
660 	    container_of(work, struct ttm_bo_device, wq.work);
661 
662 	if (!ttm_bo_delayed_delete(bdev, false))
663 		schedule_delayed_work(&bdev->wq,
664 				      ((HZ / 100) < 1) ? 1 : HZ / 100);
665 }
666 
667 static void ttm_bo_release(struct kref *kref)
668 {
669 	struct ttm_buffer_object *bo =
670 	    container_of(kref, struct ttm_buffer_object, kref);
671 	struct ttm_bo_device *bdev = bo->bdev;
672 	struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
673 
674 	drm_vma_offset_remove(&bdev->vma_manager, &bo->vma_node);
675 	ttm_mem_io_lock(man, false);
676 	ttm_mem_io_free_vm(bo);
677 	ttm_mem_io_unlock(man);
678 	ttm_bo_cleanup_refs_or_queue(bo);
679 	kref_put(&bo->list_kref, ttm_bo_release_list);
680 }
681 
682 void ttm_bo_put(struct ttm_buffer_object *bo)
683 {
684 	kref_put(&bo->kref, ttm_bo_release);
685 }
686 EXPORT_SYMBOL(ttm_bo_put);
687 
688 int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev)
689 {
690 	return cancel_delayed_work_sync(&bdev->wq);
691 }
692 EXPORT_SYMBOL(ttm_bo_lock_delayed_workqueue);
693 
694 void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched)
695 {
696 	if (resched)
697 		schedule_delayed_work(&bdev->wq,
698 				      ((HZ / 100) < 1) ? 1 : HZ / 100);
699 }
700 EXPORT_SYMBOL(ttm_bo_unlock_delayed_workqueue);
701 
702 static int ttm_bo_evict(struct ttm_buffer_object *bo,
703 			struct ttm_operation_ctx *ctx)
704 {
705 	struct ttm_bo_device *bdev = bo->bdev;
706 	struct ttm_mem_reg evict_mem;
707 	struct ttm_placement placement;
708 	int ret = 0;
709 
710 	reservation_object_assert_held(bo->resv);
711 
712 	placement.num_placement = 0;
713 	placement.num_busy_placement = 0;
714 	bdev->driver->evict_flags(bo, &placement);
715 
716 	if (!placement.num_placement && !placement.num_busy_placement) {
717 		ret = ttm_bo_pipeline_gutting(bo);
718 		if (ret)
719 			return ret;
720 
721 		return ttm_tt_create(bo, false);
722 	}
723 
724 	evict_mem = bo->mem;
725 	evict_mem.mm_node = NULL;
726 	evict_mem.bus.io_reserved_vm = false;
727 	evict_mem.bus.io_reserved_count = 0;
728 
729 	ret = ttm_bo_mem_space(bo, &placement, &evict_mem, ctx);
730 	if (ret) {
731 		if (ret != -ERESTARTSYS) {
732 			pr_err("Failed to find memory space for buffer 0x%p eviction\n",
733 			       bo);
734 			ttm_bo_mem_space_debug(bo, &placement);
735 		}
736 		goto out;
737 	}
738 
739 	ret = ttm_bo_handle_move_mem(bo, &evict_mem, true, ctx);
740 	if (unlikely(ret)) {
741 		if (ret != -ERESTARTSYS)
742 			pr_err("Buffer eviction failed\n");
743 		ttm_bo_mem_put(bo, &evict_mem);
744 		goto out;
745 	}
746 	bo->evicted = true;
747 out:
748 	return ret;
749 }
750 
751 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
752 			      const struct ttm_place *place)
753 {
754 	/* Don't evict this BO if it's outside of the
755 	 * requested placement range
756 	 */
757 	if (place->fpfn >= (bo->mem.start + bo->mem.size) ||
758 	    (place->lpfn && place->lpfn <= bo->mem.start))
759 		return false;
760 
761 	return true;
762 }
763 EXPORT_SYMBOL(ttm_bo_eviction_valuable);
764 
765 /**
766  * Check the target bo is allowable to be evicted or swapout, including cases:
767  *
768  * a. if share same reservation object with ctx->resv, have assumption
769  * reservation objects should already be locked, so not lock again and
770  * return true directly when either the opreation allow_reserved_eviction
771  * or the target bo already is in delayed free list;
772  *
773  * b. Otherwise, trylock it.
774  */
775 static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo,
776 			struct ttm_operation_ctx *ctx, bool *locked, bool *busy)
777 {
778 	bool ret = false;
779 
780 	if (bo->resv == ctx->resv) {
781 		reservation_object_assert_held(bo->resv);
782 		if (ctx->flags & TTM_OPT_FLAG_ALLOW_RES_EVICT
783 		    || !list_empty(&bo->ddestroy))
784 			ret = true;
785 		*locked = false;
786 		if (busy)
787 			*busy = false;
788 	} else {
789 		ret = reservation_object_trylock(bo->resv);
790 		*locked = ret;
791 		if (busy)
792 			*busy = !ret;
793 	}
794 
795 	return ret;
796 }
797 
798 /**
799  * ttm_mem_evict_wait_busy - wait for a busy BO to become available
800  *
801  * @busy_bo: BO which couldn't be locked with trylock
802  * @ctx: operation context
803  * @ticket: acquire ticket
804  *
805  * Try to lock a busy buffer object to avoid failing eviction.
806  */
807 static int ttm_mem_evict_wait_busy(struct ttm_buffer_object *busy_bo,
808 				   struct ttm_operation_ctx *ctx,
809 				   struct ww_acquire_ctx *ticket)
810 {
811 	int r;
812 
813 	if (!busy_bo || !ticket)
814 		return -EBUSY;
815 
816 	if (ctx->interruptible)
817 		r = reservation_object_lock_interruptible(busy_bo->resv,
818 							  ticket);
819 	else
820 		r = reservation_object_lock(busy_bo->resv, ticket);
821 
822 	/*
823 	 * TODO: It would be better to keep the BO locked until allocation is at
824 	 * least tried one more time, but that would mean a much larger rework
825 	 * of TTM.
826 	 */
827 	if (!r)
828 		reservation_object_unlock(busy_bo->resv);
829 
830 	return r == -EDEADLK ? -EBUSY : r;
831 }
832 
833 static int ttm_mem_evict_first(struct ttm_bo_device *bdev,
834 			       uint32_t mem_type,
835 			       const struct ttm_place *place,
836 			       struct ttm_operation_ctx *ctx,
837 			       struct ww_acquire_ctx *ticket)
838 {
839 	struct ttm_buffer_object *bo = NULL, *busy_bo = NULL;
840 	struct ttm_bo_global *glob = bdev->glob;
841 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
842 	bool locked = false;
843 	unsigned i;
844 	int ret;
845 
846 	spin_lock(&glob->lru_lock);
847 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
848 		list_for_each_entry(bo, &man->lru[i], lru) {
849 			bool busy;
850 
851 			if (!ttm_bo_evict_swapout_allowable(bo, ctx, &locked,
852 							    &busy)) {
853 				if (busy && !busy_bo &&
854 				    bo->resv->lock.ctx != ticket)
855 					busy_bo = bo;
856 				continue;
857 			}
858 
859 			if (place && !bdev->driver->eviction_valuable(bo,
860 								      place)) {
861 				if (locked)
862 					reservation_object_unlock(bo->resv);
863 				continue;
864 			}
865 			break;
866 		}
867 
868 		/* If the inner loop terminated early, we have our candidate */
869 		if (&bo->lru != &man->lru[i])
870 			break;
871 
872 		bo = NULL;
873 	}
874 
875 	if (!bo) {
876 		if (busy_bo)
877 			ttm_bo_get(busy_bo);
878 		spin_unlock(&glob->lru_lock);
879 		ret = ttm_mem_evict_wait_busy(busy_bo, ctx, ticket);
880 		if (busy_bo)
881 			ttm_bo_put(busy_bo);
882 		return ret;
883 	}
884 
885 	kref_get(&bo->list_kref);
886 
887 	if (!list_empty(&bo->ddestroy)) {
888 		ret = ttm_bo_cleanup_refs(bo, ctx->interruptible,
889 					  ctx->no_wait_gpu, locked);
890 		kref_put(&bo->list_kref, ttm_bo_release_list);
891 		return ret;
892 	}
893 
894 	ttm_bo_del_from_lru(bo);
895 	spin_unlock(&glob->lru_lock);
896 
897 	ret = ttm_bo_evict(bo, ctx);
898 	if (locked) {
899 		ttm_bo_unreserve(bo);
900 	} else {
901 		spin_lock(&glob->lru_lock);
902 		ttm_bo_add_to_lru(bo);
903 		spin_unlock(&glob->lru_lock);
904 	}
905 
906 	kref_put(&bo->list_kref, ttm_bo_release_list);
907 	return ret;
908 }
909 
910 void ttm_bo_mem_put(struct ttm_buffer_object *bo, struct ttm_mem_reg *mem)
911 {
912 	struct ttm_mem_type_manager *man = &bo->bdev->man[mem->mem_type];
913 
914 	if (mem->mm_node)
915 		(*man->func->put_node)(man, mem);
916 }
917 EXPORT_SYMBOL(ttm_bo_mem_put);
918 
919 /**
920  * Add the last move fence to the BO and reserve a new shared slot.
921  */
922 static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo,
923 				 struct ttm_mem_type_manager *man,
924 				 struct ttm_mem_reg *mem)
925 {
926 	struct dma_fence *fence;
927 	int ret;
928 
929 	spin_lock(&man->move_lock);
930 	fence = dma_fence_get(man->move);
931 	spin_unlock(&man->move_lock);
932 
933 	if (fence) {
934 		reservation_object_add_shared_fence(bo->resv, fence);
935 
936 		ret = reservation_object_reserve_shared(bo->resv, 1);
937 		if (unlikely(ret)) {
938 			dma_fence_put(fence);
939 			return ret;
940 		}
941 
942 		dma_fence_put(bo->moving);
943 		bo->moving = fence;
944 	}
945 
946 	return 0;
947 }
948 
949 /**
950  * Repeatedly evict memory from the LRU for @mem_type until we create enough
951  * space, or we've evicted everything and there isn't enough space.
952  */
953 static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
954 				  const struct ttm_place *place,
955 				  struct ttm_mem_reg *mem,
956 				  struct ttm_operation_ctx *ctx)
957 {
958 	struct ttm_bo_device *bdev = bo->bdev;
959 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
960 	int ret;
961 
962 	do {
963 		ret = (*man->func->get_node)(man, bo, place, mem);
964 		if (unlikely(ret != 0))
965 			return ret;
966 		if (mem->mm_node)
967 			break;
968 		ret = ttm_mem_evict_first(bdev, mem->mem_type, place, ctx,
969 					  bo->resv->lock.ctx);
970 		if (unlikely(ret != 0))
971 			return ret;
972 	} while (1);
973 
974 	return ttm_bo_add_move_fence(bo, man, mem);
975 }
976 
977 static uint32_t ttm_bo_select_caching(struct ttm_mem_type_manager *man,
978 				      uint32_t cur_placement,
979 				      uint32_t proposed_placement)
980 {
981 	uint32_t caching = proposed_placement & TTM_PL_MASK_CACHING;
982 	uint32_t result = proposed_placement & ~TTM_PL_MASK_CACHING;
983 
984 	/**
985 	 * Keep current caching if possible.
986 	 */
987 
988 	if ((cur_placement & caching) != 0)
989 		result |= (cur_placement & caching);
990 	else if ((man->default_caching & caching) != 0)
991 		result |= man->default_caching;
992 	else if ((TTM_PL_FLAG_CACHED & caching) != 0)
993 		result |= TTM_PL_FLAG_CACHED;
994 	else if ((TTM_PL_FLAG_WC & caching) != 0)
995 		result |= TTM_PL_FLAG_WC;
996 	else if ((TTM_PL_FLAG_UNCACHED & caching) != 0)
997 		result |= TTM_PL_FLAG_UNCACHED;
998 
999 	return result;
1000 }
1001 
1002 static bool ttm_bo_mt_compatible(struct ttm_mem_type_manager *man,
1003 				 uint32_t mem_type,
1004 				 const struct ttm_place *place,
1005 				 uint32_t *masked_placement)
1006 {
1007 	uint32_t cur_flags = ttm_bo_type_flags(mem_type);
1008 
1009 	if ((cur_flags & place->flags & TTM_PL_MASK_MEM) == 0)
1010 		return false;
1011 
1012 	if ((place->flags & man->available_caching) == 0)
1013 		return false;
1014 
1015 	cur_flags |= (place->flags & man->available_caching);
1016 
1017 	*masked_placement = cur_flags;
1018 	return true;
1019 }
1020 
1021 /**
1022  * ttm_bo_mem_placement - check if placement is compatible
1023  * @bo: BO to find memory for
1024  * @place: where to search
1025  * @mem: the memory object to fill in
1026  * @ctx: operation context
1027  *
1028  * Check if placement is compatible and fill in mem structure.
1029  * Returns -EBUSY if placement won't work or negative error code.
1030  * 0 when placement can be used.
1031  */
1032 static int ttm_bo_mem_placement(struct ttm_buffer_object *bo,
1033 				const struct ttm_place *place,
1034 				struct ttm_mem_reg *mem,
1035 				struct ttm_operation_ctx *ctx)
1036 {
1037 	struct ttm_bo_device *bdev = bo->bdev;
1038 	uint32_t mem_type = TTM_PL_SYSTEM;
1039 	struct ttm_mem_type_manager *man;
1040 	uint32_t cur_flags = 0;
1041 	int ret;
1042 
1043 	ret = ttm_mem_type_from_place(place, &mem_type);
1044 	if (ret)
1045 		return ret;
1046 
1047 	man = &bdev->man[mem_type];
1048 	if (!man->has_type || !man->use_type)
1049 		return -EBUSY;
1050 
1051 	if (!ttm_bo_mt_compatible(man, mem_type, place, &cur_flags))
1052 		return -EBUSY;
1053 
1054 	cur_flags = ttm_bo_select_caching(man, bo->mem.placement, cur_flags);
1055 	/*
1056 	 * Use the access and other non-mapping-related flag bits from
1057 	 * the memory placement flags to the current flags
1058 	 */
1059 	ttm_flag_masked(&cur_flags, place->flags, ~TTM_PL_MASK_MEMTYPE);
1060 
1061 	mem->mem_type = mem_type;
1062 	mem->placement = cur_flags;
1063 
1064 	if (bo->mem.mem_type < mem_type && !list_empty(&bo->lru)) {
1065 		spin_lock(&bo->bdev->glob->lru_lock);
1066 		ttm_bo_del_from_lru(bo);
1067 		ttm_bo_add_mem_to_lru(bo, mem);
1068 		spin_unlock(&bo->bdev->glob->lru_lock);
1069 	}
1070 
1071 	return 0;
1072 }
1073 
1074 /**
1075  * Creates space for memory region @mem according to its type.
1076  *
1077  * This function first searches for free space in compatible memory types in
1078  * the priority order defined by the driver.  If free space isn't found, then
1079  * ttm_bo_mem_force_space is attempted in priority order to evict and find
1080  * space.
1081  */
1082 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
1083 			struct ttm_placement *placement,
1084 			struct ttm_mem_reg *mem,
1085 			struct ttm_operation_ctx *ctx)
1086 {
1087 	struct ttm_bo_device *bdev = bo->bdev;
1088 	bool type_found = false;
1089 	int i, ret;
1090 
1091 	ret = reservation_object_reserve_shared(bo->resv, 1);
1092 	if (unlikely(ret))
1093 		return ret;
1094 
1095 	mem->mm_node = NULL;
1096 	for (i = 0; i < placement->num_placement; ++i) {
1097 		const struct ttm_place *place = &placement->placement[i];
1098 		struct ttm_mem_type_manager *man;
1099 
1100 		ret = ttm_bo_mem_placement(bo, place, mem, ctx);
1101 		if (ret == -EBUSY)
1102 			continue;
1103 		if (ret)
1104 			goto error;
1105 
1106 		type_found = true;
1107 		mem->mm_node = NULL;
1108 		if (mem->mem_type == TTM_PL_SYSTEM)
1109 			return 0;
1110 
1111 		man = &bdev->man[mem->mem_type];
1112 		ret = (*man->func->get_node)(man, bo, place, mem);
1113 		if (unlikely(ret))
1114 			goto error;
1115 
1116 		if (mem->mm_node) {
1117 			ret = ttm_bo_add_move_fence(bo, man, mem);
1118 			if (unlikely(ret)) {
1119 				(*man->func->put_node)(man, mem);
1120 				goto error;
1121 			}
1122 			return 0;
1123 		}
1124 	}
1125 
1126 	for (i = 0; i < placement->num_busy_placement; ++i) {
1127 		const struct ttm_place *place = &placement->busy_placement[i];
1128 
1129 		ret = ttm_bo_mem_placement(bo, place, mem, ctx);
1130 		if (ret == -EBUSY)
1131 			continue;
1132 		if (ret)
1133 			goto error;
1134 
1135 		type_found = true;
1136 		mem->mm_node = NULL;
1137 		if (mem->mem_type == TTM_PL_SYSTEM)
1138 			return 0;
1139 
1140 		ret = ttm_bo_mem_force_space(bo, place, mem, ctx);
1141 		if (ret == 0 && mem->mm_node)
1142 			return 0;
1143 
1144 		if (ret && ret != -EBUSY)
1145 			goto error;
1146 	}
1147 
1148 	ret = -ENOMEM;
1149 	if (!type_found) {
1150 		pr_err(TTM_PFX "No compatible memory type found\n");
1151 		ret = -EINVAL;
1152 	}
1153 
1154 error:
1155 	if (bo->mem.mem_type == TTM_PL_SYSTEM && !list_empty(&bo->lru)) {
1156 		spin_lock(&bo->bdev->glob->lru_lock);
1157 		ttm_bo_move_to_lru_tail(bo, NULL);
1158 		spin_unlock(&bo->bdev->glob->lru_lock);
1159 	}
1160 
1161 	return ret;
1162 }
1163 EXPORT_SYMBOL(ttm_bo_mem_space);
1164 
1165 static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
1166 			      struct ttm_placement *placement,
1167 			      struct ttm_operation_ctx *ctx)
1168 {
1169 	int ret = 0;
1170 	struct ttm_mem_reg mem;
1171 
1172 	reservation_object_assert_held(bo->resv);
1173 
1174 	mem.num_pages = bo->num_pages;
1175 	mem.size = mem.num_pages << PAGE_SHIFT;
1176 	mem.page_alignment = bo->mem.page_alignment;
1177 	mem.bus.io_reserved_vm = false;
1178 	mem.bus.io_reserved_count = 0;
1179 	/*
1180 	 * Determine where to move the buffer.
1181 	 */
1182 	ret = ttm_bo_mem_space(bo, placement, &mem, ctx);
1183 	if (ret)
1184 		goto out_unlock;
1185 	ret = ttm_bo_handle_move_mem(bo, &mem, false, ctx);
1186 out_unlock:
1187 	if (ret && mem.mm_node)
1188 		ttm_bo_mem_put(bo, &mem);
1189 	return ret;
1190 }
1191 
1192 static bool ttm_bo_places_compat(const struct ttm_place *places,
1193 				 unsigned num_placement,
1194 				 struct ttm_mem_reg *mem,
1195 				 uint32_t *new_flags)
1196 {
1197 	unsigned i;
1198 
1199 	for (i = 0; i < num_placement; i++) {
1200 		const struct ttm_place *heap = &places[i];
1201 
1202 		if (mem->mm_node && (mem->start < heap->fpfn ||
1203 		     (heap->lpfn != 0 && (mem->start + mem->num_pages) > heap->lpfn)))
1204 			continue;
1205 
1206 		*new_flags = heap->flags;
1207 		if ((*new_flags & mem->placement & TTM_PL_MASK_CACHING) &&
1208 		    (*new_flags & mem->placement & TTM_PL_MASK_MEM) &&
1209 		    (!(*new_flags & TTM_PL_FLAG_CONTIGUOUS) ||
1210 		     (mem->placement & TTM_PL_FLAG_CONTIGUOUS)))
1211 			return true;
1212 	}
1213 	return false;
1214 }
1215 
1216 bool ttm_bo_mem_compat(struct ttm_placement *placement,
1217 		       struct ttm_mem_reg *mem,
1218 		       uint32_t *new_flags)
1219 {
1220 	if (ttm_bo_places_compat(placement->placement, placement->num_placement,
1221 				 mem, new_flags))
1222 		return true;
1223 
1224 	if ((placement->busy_placement != placement->placement ||
1225 	     placement->num_busy_placement > placement->num_placement) &&
1226 	    ttm_bo_places_compat(placement->busy_placement,
1227 				 placement->num_busy_placement,
1228 				 mem, new_flags))
1229 		return true;
1230 
1231 	return false;
1232 }
1233 EXPORT_SYMBOL(ttm_bo_mem_compat);
1234 
1235 int ttm_bo_validate(struct ttm_buffer_object *bo,
1236 		    struct ttm_placement *placement,
1237 		    struct ttm_operation_ctx *ctx)
1238 {
1239 	int ret;
1240 	uint32_t new_flags;
1241 
1242 	reservation_object_assert_held(bo->resv);
1243 	/*
1244 	 * Check whether we need to move buffer.
1245 	 */
1246 	if (!ttm_bo_mem_compat(placement, &bo->mem, &new_flags)) {
1247 		ret = ttm_bo_move_buffer(bo, placement, ctx);
1248 		if (ret)
1249 			return ret;
1250 	} else {
1251 		/*
1252 		 * Use the access and other non-mapping-related flag bits from
1253 		 * the compatible memory placement flags to the active flags
1254 		 */
1255 		ttm_flag_masked(&bo->mem.placement, new_flags,
1256 				~TTM_PL_MASK_MEMTYPE);
1257 	}
1258 	/*
1259 	 * We might need to add a TTM.
1260 	 */
1261 	if (bo->mem.mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {
1262 		ret = ttm_tt_create(bo, true);
1263 		if (ret)
1264 			return ret;
1265 	}
1266 	return 0;
1267 }
1268 EXPORT_SYMBOL(ttm_bo_validate);
1269 
1270 int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
1271 			 struct ttm_buffer_object *bo,
1272 			 unsigned long size,
1273 			 enum ttm_bo_type type,
1274 			 struct ttm_placement *placement,
1275 			 uint32_t page_alignment,
1276 			 struct ttm_operation_ctx *ctx,
1277 			 size_t acc_size,
1278 			 struct sg_table *sg,
1279 			 struct reservation_object *resv,
1280 			 void (*destroy) (struct ttm_buffer_object *))
1281 {
1282 	int ret = 0;
1283 	unsigned long num_pages;
1284 	struct ttm_mem_global *mem_glob = bdev->glob->mem_glob;
1285 	bool locked;
1286 
1287 	ret = ttm_mem_global_alloc(mem_glob, acc_size, ctx);
1288 	if (ret) {
1289 		pr_err("Out of kernel memory\n");
1290 		if (destroy)
1291 			(*destroy)(bo);
1292 		else
1293 			kfree(bo);
1294 		return -ENOMEM;
1295 	}
1296 
1297 	num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1298 	if (num_pages == 0) {
1299 		pr_err("Illegal buffer object size\n");
1300 		if (destroy)
1301 			(*destroy)(bo);
1302 		else
1303 			kfree(bo);
1304 		ttm_mem_global_free(mem_glob, acc_size);
1305 		return -EINVAL;
1306 	}
1307 	bo->destroy = destroy ? destroy : ttm_bo_default_destroy;
1308 
1309 	kref_init(&bo->kref);
1310 	kref_init(&bo->list_kref);
1311 	atomic_set(&bo->cpu_writers, 0);
1312 	INIT_LIST_HEAD(&bo->lru);
1313 	INIT_LIST_HEAD(&bo->ddestroy);
1314 	INIT_LIST_HEAD(&bo->swap);
1315 	INIT_LIST_HEAD(&bo->io_reserve_lru);
1316 	mutex_init(&bo->wu_mutex);
1317 	bo->bdev = bdev;
1318 	bo->type = type;
1319 	bo->num_pages = num_pages;
1320 	bo->mem.size = num_pages << PAGE_SHIFT;
1321 	bo->mem.mem_type = TTM_PL_SYSTEM;
1322 	bo->mem.num_pages = bo->num_pages;
1323 	bo->mem.mm_node = NULL;
1324 	bo->mem.page_alignment = page_alignment;
1325 	bo->mem.bus.io_reserved_vm = false;
1326 	bo->mem.bus.io_reserved_count = 0;
1327 	bo->moving = NULL;
1328 	bo->mem.placement = (TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED);
1329 	bo->acc_size = acc_size;
1330 	bo->sg = sg;
1331 	if (resv) {
1332 		bo->resv = resv;
1333 		reservation_object_assert_held(bo->resv);
1334 	} else {
1335 		bo->resv = &bo->ttm_resv;
1336 	}
1337 	reservation_object_init(&bo->ttm_resv);
1338 	atomic_inc(&bo->bdev->glob->bo_count);
1339 	drm_vma_node_reset(&bo->vma_node);
1340 
1341 	/*
1342 	 * For ttm_bo_type_device buffers, allocate
1343 	 * address space from the device.
1344 	 */
1345 	if (bo->type == ttm_bo_type_device ||
1346 	    bo->type == ttm_bo_type_sg)
1347 		ret = drm_vma_offset_add(&bdev->vma_manager, &bo->vma_node,
1348 					 bo->mem.num_pages);
1349 
1350 	/* passed reservation objects should already be locked,
1351 	 * since otherwise lockdep will be angered in radeon.
1352 	 */
1353 	if (!resv) {
1354 		locked = reservation_object_trylock(bo->resv);
1355 		WARN_ON(!locked);
1356 	}
1357 
1358 	if (likely(!ret))
1359 		ret = ttm_bo_validate(bo, placement, ctx);
1360 
1361 	if (unlikely(ret)) {
1362 		if (!resv)
1363 			ttm_bo_unreserve(bo);
1364 
1365 		ttm_bo_put(bo);
1366 		return ret;
1367 	}
1368 
1369 	if (resv && !(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
1370 		spin_lock(&bdev->glob->lru_lock);
1371 		ttm_bo_add_to_lru(bo);
1372 		spin_unlock(&bdev->glob->lru_lock);
1373 	}
1374 
1375 	return ret;
1376 }
1377 EXPORT_SYMBOL(ttm_bo_init_reserved);
1378 
1379 int ttm_bo_init(struct ttm_bo_device *bdev,
1380 		struct ttm_buffer_object *bo,
1381 		unsigned long size,
1382 		enum ttm_bo_type type,
1383 		struct ttm_placement *placement,
1384 		uint32_t page_alignment,
1385 		bool interruptible,
1386 		size_t acc_size,
1387 		struct sg_table *sg,
1388 		struct reservation_object *resv,
1389 		void (*destroy) (struct ttm_buffer_object *))
1390 {
1391 	struct ttm_operation_ctx ctx = { interruptible, false };
1392 	int ret;
1393 
1394 	ret = ttm_bo_init_reserved(bdev, bo, size, type, placement,
1395 				   page_alignment, &ctx, acc_size,
1396 				   sg, resv, destroy);
1397 	if (ret)
1398 		return ret;
1399 
1400 	if (!resv)
1401 		ttm_bo_unreserve(bo);
1402 
1403 	return 0;
1404 }
1405 EXPORT_SYMBOL(ttm_bo_init);
1406 
1407 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
1408 		       unsigned long bo_size,
1409 		       unsigned struct_size)
1410 {
1411 	unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
1412 	size_t size = 0;
1413 
1414 	size += ttm_round_pot(struct_size);
1415 	size += ttm_round_pot(npages * sizeof(void *));
1416 	size += ttm_round_pot(sizeof(struct ttm_tt));
1417 	return size;
1418 }
1419 EXPORT_SYMBOL(ttm_bo_acc_size);
1420 
1421 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
1422 			   unsigned long bo_size,
1423 			   unsigned struct_size)
1424 {
1425 	unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
1426 	size_t size = 0;
1427 
1428 	size += ttm_round_pot(struct_size);
1429 	size += ttm_round_pot(npages * (2*sizeof(void *) + sizeof(dma_addr_t)));
1430 	size += ttm_round_pot(sizeof(struct ttm_dma_tt));
1431 	return size;
1432 }
1433 EXPORT_SYMBOL(ttm_bo_dma_acc_size);
1434 
1435 int ttm_bo_create(struct ttm_bo_device *bdev,
1436 			unsigned long size,
1437 			enum ttm_bo_type type,
1438 			struct ttm_placement *placement,
1439 			uint32_t page_alignment,
1440 			bool interruptible,
1441 			struct ttm_buffer_object **p_bo)
1442 {
1443 	struct ttm_buffer_object *bo;
1444 	size_t acc_size;
1445 	int ret;
1446 
1447 	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
1448 	if (unlikely(bo == NULL))
1449 		return -ENOMEM;
1450 
1451 	acc_size = ttm_bo_acc_size(bdev, size, sizeof(struct ttm_buffer_object));
1452 	ret = ttm_bo_init(bdev, bo, size, type, placement, page_alignment,
1453 			  interruptible, acc_size,
1454 			  NULL, NULL, NULL);
1455 	if (likely(ret == 0))
1456 		*p_bo = bo;
1457 
1458 	return ret;
1459 }
1460 EXPORT_SYMBOL(ttm_bo_create);
1461 
1462 static int ttm_bo_force_list_clean(struct ttm_bo_device *bdev,
1463 				   unsigned mem_type)
1464 {
1465 	struct ttm_operation_ctx ctx = {
1466 		.interruptible = false,
1467 		.no_wait_gpu = false,
1468 		.flags = TTM_OPT_FLAG_FORCE_ALLOC
1469 	};
1470 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
1471 	struct ttm_bo_global *glob = bdev->glob;
1472 	struct dma_fence *fence;
1473 	int ret;
1474 	unsigned i;
1475 
1476 	/*
1477 	 * Can't use standard list traversal since we're unlocking.
1478 	 */
1479 
1480 	spin_lock(&glob->lru_lock);
1481 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
1482 		while (!list_empty(&man->lru[i])) {
1483 			spin_unlock(&glob->lru_lock);
1484 			ret = ttm_mem_evict_first(bdev, mem_type, NULL, &ctx,
1485 						  NULL);
1486 			if (ret)
1487 				return ret;
1488 			spin_lock(&glob->lru_lock);
1489 		}
1490 	}
1491 	spin_unlock(&glob->lru_lock);
1492 
1493 	spin_lock(&man->move_lock);
1494 	fence = dma_fence_get(man->move);
1495 	spin_unlock(&man->move_lock);
1496 
1497 	if (fence) {
1498 		ret = dma_fence_wait(fence, false);
1499 		dma_fence_put(fence);
1500 		if (ret)
1501 			return ret;
1502 	}
1503 
1504 	return 0;
1505 }
1506 
1507 int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type)
1508 {
1509 	struct ttm_mem_type_manager *man;
1510 	int ret = -EINVAL;
1511 
1512 	if (mem_type >= TTM_NUM_MEM_TYPES) {
1513 		pr_err("Illegal memory type %d\n", mem_type);
1514 		return ret;
1515 	}
1516 	man = &bdev->man[mem_type];
1517 
1518 	if (!man->has_type) {
1519 		pr_err("Trying to take down uninitialized memory manager type %u\n",
1520 		       mem_type);
1521 		return ret;
1522 	}
1523 
1524 	man->use_type = false;
1525 	man->has_type = false;
1526 
1527 	ret = 0;
1528 	if (mem_type > 0) {
1529 		ret = ttm_bo_force_list_clean(bdev, mem_type);
1530 		if (ret) {
1531 			pr_err("Cleanup eviction failed\n");
1532 			return ret;
1533 		}
1534 
1535 		ret = (*man->func->takedown)(man);
1536 	}
1537 
1538 	dma_fence_put(man->move);
1539 	man->move = NULL;
1540 
1541 	return ret;
1542 }
1543 EXPORT_SYMBOL(ttm_bo_clean_mm);
1544 
1545 int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type)
1546 {
1547 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
1548 
1549 	if (mem_type == 0 || mem_type >= TTM_NUM_MEM_TYPES) {
1550 		pr_err("Illegal memory manager memory type %u\n", mem_type);
1551 		return -EINVAL;
1552 	}
1553 
1554 	if (!man->has_type) {
1555 		pr_err("Memory type %u has not been initialized\n", mem_type);
1556 		return 0;
1557 	}
1558 
1559 	return ttm_bo_force_list_clean(bdev, mem_type);
1560 }
1561 EXPORT_SYMBOL(ttm_bo_evict_mm);
1562 
1563 int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
1564 			unsigned long p_size)
1565 {
1566 	int ret;
1567 	struct ttm_mem_type_manager *man;
1568 	unsigned i;
1569 
1570 	BUG_ON(type >= TTM_NUM_MEM_TYPES);
1571 	man = &bdev->man[type];
1572 	BUG_ON(man->has_type);
1573 	man->io_reserve_fastpath = true;
1574 	man->use_io_reserve_lru = false;
1575 	mutex_init(&man->io_reserve_mutex);
1576 	spin_lock_init(&man->move_lock);
1577 	INIT_LIST_HEAD(&man->io_reserve_lru);
1578 
1579 	ret = bdev->driver->init_mem_type(bdev, type, man);
1580 	if (ret)
1581 		return ret;
1582 	man->bdev = bdev;
1583 
1584 	if (type != TTM_PL_SYSTEM) {
1585 		ret = (*man->func->init)(man, p_size);
1586 		if (ret)
1587 			return ret;
1588 	}
1589 	man->has_type = true;
1590 	man->use_type = true;
1591 	man->size = p_size;
1592 
1593 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
1594 		INIT_LIST_HEAD(&man->lru[i]);
1595 	man->move = NULL;
1596 
1597 	return 0;
1598 }
1599 EXPORT_SYMBOL(ttm_bo_init_mm);
1600 
1601 static void ttm_bo_global_kobj_release(struct kobject *kobj)
1602 {
1603 	struct ttm_bo_global *glob =
1604 		container_of(kobj, struct ttm_bo_global, kobj);
1605 
1606 	__free_page(glob->dummy_read_page);
1607 }
1608 
1609 static void ttm_bo_global_release(void)
1610 {
1611 	struct ttm_bo_global *glob = &ttm_bo_glob;
1612 
1613 	mutex_lock(&ttm_global_mutex);
1614 	if (--ttm_bo_glob_use_count > 0)
1615 		goto out;
1616 
1617 	kobject_del(&glob->kobj);
1618 	kobject_put(&glob->kobj);
1619 	ttm_mem_global_release(&ttm_mem_glob);
1620 	memset(glob, 0, sizeof(*glob));
1621 out:
1622 	mutex_unlock(&ttm_global_mutex);
1623 }
1624 
1625 static int ttm_bo_global_init(void)
1626 {
1627 	struct ttm_bo_global *glob = &ttm_bo_glob;
1628 	int ret = 0;
1629 	unsigned i;
1630 
1631 	mutex_lock(&ttm_global_mutex);
1632 	if (++ttm_bo_glob_use_count > 1)
1633 		goto out;
1634 
1635 	ret = ttm_mem_global_init(&ttm_mem_glob);
1636 	if (ret)
1637 		goto out;
1638 
1639 	spin_lock_init(&glob->lru_lock);
1640 	glob->mem_glob = &ttm_mem_glob;
1641 	glob->mem_glob->bo_glob = glob;
1642 	glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32);
1643 
1644 	if (unlikely(glob->dummy_read_page == NULL)) {
1645 		ret = -ENOMEM;
1646 		goto out;
1647 	}
1648 
1649 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
1650 		INIT_LIST_HEAD(&glob->swap_lru[i]);
1651 	INIT_LIST_HEAD(&glob->device_list);
1652 	atomic_set(&glob->bo_count, 0);
1653 
1654 	ret = kobject_init_and_add(
1655 		&glob->kobj, &ttm_bo_glob_kobj_type, ttm_get_kobj(), "buffer_objects");
1656 	if (unlikely(ret != 0))
1657 		kobject_put(&glob->kobj);
1658 out:
1659 	mutex_unlock(&ttm_global_mutex);
1660 	return ret;
1661 }
1662 
1663 int ttm_bo_device_release(struct ttm_bo_device *bdev)
1664 {
1665 	int ret = 0;
1666 	unsigned i = TTM_NUM_MEM_TYPES;
1667 	struct ttm_mem_type_manager *man;
1668 	struct ttm_bo_global *glob = bdev->glob;
1669 
1670 	while (i--) {
1671 		man = &bdev->man[i];
1672 		if (man->has_type) {
1673 			man->use_type = false;
1674 			if ((i != TTM_PL_SYSTEM) && ttm_bo_clean_mm(bdev, i)) {
1675 				ret = -EBUSY;
1676 				pr_err("DRM memory manager type %d is not clean\n",
1677 				       i);
1678 			}
1679 			man->has_type = false;
1680 		}
1681 	}
1682 
1683 	mutex_lock(&ttm_global_mutex);
1684 	list_del(&bdev->device_list);
1685 	mutex_unlock(&ttm_global_mutex);
1686 
1687 	cancel_delayed_work_sync(&bdev->wq);
1688 
1689 	if (ttm_bo_delayed_delete(bdev, true))
1690 		pr_debug("Delayed destroy list was clean\n");
1691 
1692 	spin_lock(&glob->lru_lock);
1693 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
1694 		if (list_empty(&bdev->man[0].lru[0]))
1695 			pr_debug("Swap list %d was clean\n", i);
1696 	spin_unlock(&glob->lru_lock);
1697 
1698 	drm_vma_offset_manager_destroy(&bdev->vma_manager);
1699 
1700 	if (!ret)
1701 		ttm_bo_global_release();
1702 
1703 	return ret;
1704 }
1705 EXPORT_SYMBOL(ttm_bo_device_release);
1706 
1707 int ttm_bo_device_init(struct ttm_bo_device *bdev,
1708 		       struct ttm_bo_driver *driver,
1709 		       struct address_space *mapping,
1710 		       bool need_dma32)
1711 {
1712 	struct ttm_bo_global *glob = &ttm_bo_glob;
1713 	int ret;
1714 
1715 	ret = ttm_bo_global_init();
1716 	if (ret)
1717 		return ret;
1718 
1719 	bdev->driver = driver;
1720 
1721 	memset(bdev->man, 0, sizeof(bdev->man));
1722 
1723 	/*
1724 	 * Initialize the system memory buffer type.
1725 	 * Other types need to be driver / IOCTL initialized.
1726 	 */
1727 	ret = ttm_bo_init_mm(bdev, TTM_PL_SYSTEM, 0);
1728 	if (unlikely(ret != 0))
1729 		goto out_no_sys;
1730 
1731 	drm_vma_offset_manager_init(&bdev->vma_manager,
1732 				    DRM_FILE_PAGE_OFFSET_START,
1733 				    DRM_FILE_PAGE_OFFSET_SIZE);
1734 	INIT_DELAYED_WORK(&bdev->wq, ttm_bo_delayed_workqueue);
1735 	INIT_LIST_HEAD(&bdev->ddestroy);
1736 	bdev->dev_mapping = mapping;
1737 	bdev->glob = glob;
1738 	bdev->need_dma32 = need_dma32;
1739 	mutex_lock(&ttm_global_mutex);
1740 	list_add_tail(&bdev->device_list, &glob->device_list);
1741 	mutex_unlock(&ttm_global_mutex);
1742 
1743 	return 0;
1744 out_no_sys:
1745 	ttm_bo_global_release();
1746 	return ret;
1747 }
1748 EXPORT_SYMBOL(ttm_bo_device_init);
1749 
1750 /*
1751  * buffer object vm functions.
1752  */
1753 
1754 bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem)
1755 {
1756 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
1757 
1758 	if (!(man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
1759 		if (mem->mem_type == TTM_PL_SYSTEM)
1760 			return false;
1761 
1762 		if (man->flags & TTM_MEMTYPE_FLAG_CMA)
1763 			return false;
1764 
1765 		if (mem->placement & TTM_PL_FLAG_CACHED)
1766 			return false;
1767 	}
1768 	return true;
1769 }
1770 
1771 void ttm_bo_unmap_virtual_locked(struct ttm_buffer_object *bo)
1772 {
1773 	struct ttm_bo_device *bdev = bo->bdev;
1774 
1775 	drm_vma_node_unmap(&bo->vma_node, bdev->dev_mapping);
1776 	ttm_mem_io_free_vm(bo);
1777 }
1778 
1779 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo)
1780 {
1781 	struct ttm_bo_device *bdev = bo->bdev;
1782 	struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
1783 
1784 	ttm_mem_io_lock(man, false);
1785 	ttm_bo_unmap_virtual_locked(bo);
1786 	ttm_mem_io_unlock(man);
1787 }
1788 
1789 
1790 EXPORT_SYMBOL(ttm_bo_unmap_virtual);
1791 
1792 int ttm_bo_wait(struct ttm_buffer_object *bo,
1793 		bool interruptible, bool no_wait)
1794 {
1795 	long timeout = 15 * HZ;
1796 
1797 	if (no_wait) {
1798 		if (reservation_object_test_signaled_rcu(bo->resv, true))
1799 			return 0;
1800 		else
1801 			return -EBUSY;
1802 	}
1803 
1804 	timeout = reservation_object_wait_timeout_rcu(bo->resv, true,
1805 						      interruptible, timeout);
1806 	if (timeout < 0)
1807 		return timeout;
1808 
1809 	if (timeout == 0)
1810 		return -EBUSY;
1811 
1812 	reservation_object_add_excl_fence(bo->resv, NULL);
1813 	return 0;
1814 }
1815 EXPORT_SYMBOL(ttm_bo_wait);
1816 
1817 int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait)
1818 {
1819 	int ret = 0;
1820 
1821 	/*
1822 	 * Using ttm_bo_reserve makes sure the lru lists are updated.
1823 	 */
1824 
1825 	ret = ttm_bo_reserve(bo, true, no_wait, NULL);
1826 	if (unlikely(ret != 0))
1827 		return ret;
1828 	ret = ttm_bo_wait(bo, true, no_wait);
1829 	if (likely(ret == 0))
1830 		atomic_inc(&bo->cpu_writers);
1831 	ttm_bo_unreserve(bo);
1832 	return ret;
1833 }
1834 EXPORT_SYMBOL(ttm_bo_synccpu_write_grab);
1835 
1836 void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo)
1837 {
1838 	atomic_dec(&bo->cpu_writers);
1839 }
1840 EXPORT_SYMBOL(ttm_bo_synccpu_write_release);
1841 
1842 /**
1843  * A buffer object shrink method that tries to swap out the first
1844  * buffer object on the bo_global::swap_lru list.
1845  */
1846 int ttm_bo_swapout(struct ttm_bo_global *glob, struct ttm_operation_ctx *ctx)
1847 {
1848 	struct ttm_buffer_object *bo;
1849 	int ret = -EBUSY;
1850 	bool locked;
1851 	unsigned i;
1852 
1853 	spin_lock(&glob->lru_lock);
1854 	for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
1855 		list_for_each_entry(bo, &glob->swap_lru[i], swap) {
1856 			if (ttm_bo_evict_swapout_allowable(bo, ctx, &locked,
1857 							   NULL)) {
1858 				ret = 0;
1859 				break;
1860 			}
1861 		}
1862 		if (!ret)
1863 			break;
1864 	}
1865 
1866 	if (ret) {
1867 		spin_unlock(&glob->lru_lock);
1868 		return ret;
1869 	}
1870 
1871 	kref_get(&bo->list_kref);
1872 
1873 	if (!list_empty(&bo->ddestroy)) {
1874 		ret = ttm_bo_cleanup_refs(bo, false, false, locked);
1875 		kref_put(&bo->list_kref, ttm_bo_release_list);
1876 		return ret;
1877 	}
1878 
1879 	ttm_bo_del_from_lru(bo);
1880 	spin_unlock(&glob->lru_lock);
1881 
1882 	/**
1883 	 * Move to system cached
1884 	 */
1885 
1886 	if (bo->mem.mem_type != TTM_PL_SYSTEM ||
1887 	    bo->ttm->caching_state != tt_cached) {
1888 		struct ttm_operation_ctx ctx = { false, false };
1889 		struct ttm_mem_reg evict_mem;
1890 
1891 		evict_mem = bo->mem;
1892 		evict_mem.mm_node = NULL;
1893 		evict_mem.placement = TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED;
1894 		evict_mem.mem_type = TTM_PL_SYSTEM;
1895 
1896 		ret = ttm_bo_handle_move_mem(bo, &evict_mem, true, &ctx);
1897 		if (unlikely(ret != 0))
1898 			goto out;
1899 	}
1900 
1901 	/**
1902 	 * Make sure BO is idle.
1903 	 */
1904 
1905 	ret = ttm_bo_wait(bo, false, false);
1906 	if (unlikely(ret != 0))
1907 		goto out;
1908 
1909 	ttm_bo_unmap_virtual(bo);
1910 
1911 	/**
1912 	 * Swap out. Buffer will be swapped in again as soon as
1913 	 * anyone tries to access a ttm page.
1914 	 */
1915 
1916 	if (bo->bdev->driver->swap_notify)
1917 		bo->bdev->driver->swap_notify(bo);
1918 
1919 	ret = ttm_tt_swapout(bo->ttm, bo->persistent_swap_storage);
1920 out:
1921 
1922 	/**
1923 	 *
1924 	 * Unreserve without putting on LRU to avoid swapping out an
1925 	 * already swapped buffer.
1926 	 */
1927 	if (locked)
1928 		reservation_object_unlock(bo->resv);
1929 	kref_put(&bo->list_kref, ttm_bo_release_list);
1930 	return ret;
1931 }
1932 EXPORT_SYMBOL(ttm_bo_swapout);
1933 
1934 void ttm_bo_swapout_all(struct ttm_bo_device *bdev)
1935 {
1936 	struct ttm_operation_ctx ctx = {
1937 		.interruptible = false,
1938 		.no_wait_gpu = false
1939 	};
1940 
1941 	while (ttm_bo_swapout(bdev->glob, &ctx) == 0)
1942 		;
1943 }
1944 EXPORT_SYMBOL(ttm_bo_swapout_all);
1945 
1946 /**
1947  * ttm_bo_wait_unreserved - interruptible wait for a buffer object to become
1948  * unreserved
1949  *
1950  * @bo: Pointer to buffer
1951  */
1952 int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo)
1953 {
1954 	int ret;
1955 
1956 	/*
1957 	 * In the absense of a wait_unlocked API,
1958 	 * Use the bo::wu_mutex to avoid triggering livelocks due to
1959 	 * concurrent use of this function. Note that this use of
1960 	 * bo::wu_mutex can go away if we change locking order to
1961 	 * mmap_sem -> bo::reserve.
1962 	 */
1963 	ret = mutex_lock_interruptible(&bo->wu_mutex);
1964 	if (unlikely(ret != 0))
1965 		return -ERESTARTSYS;
1966 	if (!ww_mutex_is_locked(&bo->resv->lock))
1967 		goto out_unlock;
1968 	ret = reservation_object_lock_interruptible(bo->resv, NULL);
1969 	if (ret == -EINTR)
1970 		ret = -ERESTARTSYS;
1971 	if (unlikely(ret != 0))
1972 		goto out_unlock;
1973 	reservation_object_unlock(bo->resv);
1974 
1975 out_unlock:
1976 	mutex_unlock(&bo->wu_mutex);
1977 	return ret;
1978 }
1979