1 /**************************************************************************
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
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:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
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.
26 **************************************************************************/
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
31 #define pr_fmt(fmt) "[TTM] " fmt
33 #include <drm/ttm/ttm_module.h>
34 #include <drm/ttm/ttm_bo_driver.h>
35 #include <drm/ttm/ttm_placement.h>
36 #include <linux/jiffies.h>
37 #include <linux/slab.h>
38 #include <linux/sched.h>
40 #include <linux/file.h>
41 #include <linux/module.h>
42 #include <linux/atomic.h>
43 #include <linux/reservation.h>
45 #define TTM_ASSERT_LOCKED(param)
46 #define TTM_DEBUG(fmt, arg...)
47 #define TTM_BO_HASH_ORDER 13
49 static int ttm_bo_swapout(struct ttm_mem_shrink *shrink);
50 static void ttm_bo_global_kobj_release(struct kobject *kobj);
52 static struct attribute ttm_bo_count = {
57 static inline int ttm_mem_type_from_place(const struct ttm_place *place,
62 for (i = 0; i <= TTM_PL_PRIV5; i++)
63 if (place->flags & (1 << i)) {
70 static void ttm_mem_type_debug(struct ttm_bo_device *bdev, int mem_type)
72 struct ttm_mem_type_manager *man = &bdev->man[mem_type];
74 pr_err(" has_type: %d\n", man->has_type);
75 pr_err(" use_type: %d\n", man->use_type);
76 pr_err(" flags: 0x%08X\n", man->flags);
77 pr_err(" gpu_offset: 0x%08llX\n", man->gpu_offset);
78 pr_err(" size: %llu\n", man->size);
79 pr_err(" available_caching: 0x%08X\n", man->available_caching);
80 pr_err(" default_caching: 0x%08X\n", man->default_caching);
81 if (mem_type != TTM_PL_SYSTEM)
82 (*man->func->debug)(man, TTM_PFX);
85 static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
86 struct ttm_placement *placement)
90 pr_err("No space for %p (%lu pages, %luK, %luM)\n",
91 bo, bo->mem.num_pages, bo->mem.size >> 10,
93 for (i = 0; i < placement->num_placement; i++) {
94 ret = ttm_mem_type_from_place(&placement->placement[i],
98 pr_err(" placement[%d]=0x%08X (%d)\n",
99 i, placement->placement[i].flags, mem_type);
100 ttm_mem_type_debug(bo->bdev, mem_type);
104 static ssize_t ttm_bo_global_show(struct kobject *kobj,
105 struct attribute *attr,
108 struct ttm_bo_global *glob =
109 container_of(kobj, struct ttm_bo_global, kobj);
111 return snprintf(buffer, PAGE_SIZE, "%lu\n",
112 (unsigned long) atomic_read(&glob->bo_count));
115 static struct attribute *ttm_bo_global_attrs[] = {
120 static const struct sysfs_ops ttm_bo_global_ops = {
121 .show = &ttm_bo_global_show
124 static struct kobj_type ttm_bo_glob_kobj_type = {
125 .release = &ttm_bo_global_kobj_release,
126 .sysfs_ops = &ttm_bo_global_ops,
127 .default_attrs = ttm_bo_global_attrs
131 static inline uint32_t ttm_bo_type_flags(unsigned type)
136 static void ttm_bo_release_list(struct kref *list_kref)
138 struct ttm_buffer_object *bo =
139 container_of(list_kref, struct ttm_buffer_object, list_kref);
140 struct ttm_bo_device *bdev = bo->bdev;
141 size_t acc_size = bo->acc_size;
143 BUG_ON(atomic_read(&bo->list_kref.refcount));
144 BUG_ON(atomic_read(&bo->kref.refcount));
145 BUG_ON(atomic_read(&bo->cpu_writers));
146 BUG_ON(bo->mem.mm_node != NULL);
147 BUG_ON(!list_empty(&bo->lru));
148 BUG_ON(!list_empty(&bo->ddestroy));
151 ttm_tt_destroy(bo->ttm);
152 atomic_dec(&bo->glob->bo_count);
153 if (bo->resv == &bo->ttm_resv)
154 reservation_object_fini(&bo->ttm_resv);
155 mutex_destroy(&bo->wu_mutex);
161 ttm_mem_global_free(bdev->glob->mem_glob, acc_size);
164 void ttm_bo_add_to_lru(struct ttm_buffer_object *bo)
166 struct ttm_bo_device *bdev = bo->bdev;
167 struct ttm_mem_type_manager *man;
169 lockdep_assert_held(&bo->resv->lock.base);
171 if (!(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
173 BUG_ON(!list_empty(&bo->lru));
175 man = &bdev->man[bo->mem.mem_type];
176 list_add_tail(&bo->lru, &man->lru);
177 kref_get(&bo->list_kref);
179 if (bo->ttm && !(bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) {
180 list_add_tail(&bo->swap, &bo->glob->swap_lru);
181 kref_get(&bo->list_kref);
185 EXPORT_SYMBOL(ttm_bo_add_to_lru);
187 int ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
191 if (!list_empty(&bo->swap)) {
192 list_del_init(&bo->swap);
195 if (!list_empty(&bo->lru)) {
196 list_del_init(&bo->lru);
201 * TODO: Add a driver hook to delete from
202 * driver-specific LRU's here.
208 static void ttm_bo_ref_bug(struct kref *list_kref)
213 void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count,
216 kref_sub(&bo->list_kref, count,
217 (never_free) ? ttm_bo_ref_bug : ttm_bo_release_list);
220 void ttm_bo_del_sub_from_lru(struct ttm_buffer_object *bo)
224 spin_lock(&bo->glob->lru_lock);
225 put_count = ttm_bo_del_from_lru(bo);
226 spin_unlock(&bo->glob->lru_lock);
227 ttm_bo_list_ref_sub(bo, put_count, true);
229 EXPORT_SYMBOL(ttm_bo_del_sub_from_lru);
231 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo)
235 lockdep_assert_held(&bo->resv->lock.base);
237 put_count = ttm_bo_del_from_lru(bo);
238 ttm_bo_list_ref_sub(bo, put_count, true);
239 ttm_bo_add_to_lru(bo);
241 EXPORT_SYMBOL(ttm_bo_move_to_lru_tail);
244 * Call bo->mutex locked.
246 static int ttm_bo_add_ttm(struct ttm_buffer_object *bo, bool zero_alloc)
248 struct ttm_bo_device *bdev = bo->bdev;
249 struct ttm_bo_global *glob = bo->glob;
251 uint32_t page_flags = 0;
253 TTM_ASSERT_LOCKED(&bo->mutex);
256 if (bdev->need_dma32)
257 page_flags |= TTM_PAGE_FLAG_DMA32;
260 case ttm_bo_type_device:
262 page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
263 case ttm_bo_type_kernel:
264 bo->ttm = bdev->driver->ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,
265 page_flags, glob->dummy_read_page);
266 if (unlikely(bo->ttm == NULL))
270 bo->ttm = bdev->driver->ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,
271 page_flags | TTM_PAGE_FLAG_SG,
272 glob->dummy_read_page);
273 if (unlikely(bo->ttm == NULL)) {
277 bo->ttm->sg = bo->sg;
280 pr_err("Illegal buffer object type\n");
288 static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
289 struct ttm_mem_reg *mem,
290 bool evict, bool interruptible,
293 struct ttm_bo_device *bdev = bo->bdev;
294 bool old_is_pci = ttm_mem_reg_is_pci(bdev, &bo->mem);
295 bool new_is_pci = ttm_mem_reg_is_pci(bdev, mem);
296 struct ttm_mem_type_manager *old_man = &bdev->man[bo->mem.mem_type];
297 struct ttm_mem_type_manager *new_man = &bdev->man[mem->mem_type];
300 if (old_is_pci || new_is_pci ||
301 ((mem->placement & bo->mem.placement & TTM_PL_MASK_CACHING) == 0)) {
302 ret = ttm_mem_io_lock(old_man, true);
303 if (unlikely(ret != 0))
305 ttm_bo_unmap_virtual_locked(bo);
306 ttm_mem_io_unlock(old_man);
310 * Create and bind a ttm if required.
313 if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
314 if (bo->ttm == NULL) {
315 bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);
316 ret = ttm_bo_add_ttm(bo, zero);
321 ret = ttm_tt_set_placement_caching(bo->ttm, mem->placement);
325 if (mem->mem_type != TTM_PL_SYSTEM) {
326 ret = ttm_tt_bind(bo->ttm, mem);
331 if (bo->mem.mem_type == TTM_PL_SYSTEM) {
332 if (bdev->driver->move_notify)
333 bdev->driver->move_notify(bo, mem);
340 if (bdev->driver->move_notify)
341 bdev->driver->move_notify(bo, mem);
343 if (!(old_man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
344 !(new_man->flags & TTM_MEMTYPE_FLAG_FIXED))
345 ret = ttm_bo_move_ttm(bo, evict, no_wait_gpu, mem);
346 else if (bdev->driver->move)
347 ret = bdev->driver->move(bo, evict, interruptible,
350 ret = ttm_bo_move_memcpy(bo, evict, no_wait_gpu, mem);
353 if (bdev->driver->move_notify) {
354 struct ttm_mem_reg tmp_mem = *mem;
357 bdev->driver->move_notify(bo, mem);
367 if (bdev->driver->invalidate_caches) {
368 ret = bdev->driver->invalidate_caches(bdev, bo->mem.placement);
370 pr_err("Can not flush read caches\n");
375 if (bo->mem.mm_node) {
376 bo->offset = (bo->mem.start << PAGE_SHIFT) +
377 bdev->man[bo->mem.mem_type].gpu_offset;
378 bo->cur_placement = bo->mem.placement;
385 new_man = &bdev->man[bo->mem.mem_type];
386 if ((new_man->flags & TTM_MEMTYPE_FLAG_FIXED) && bo->ttm) {
387 ttm_tt_unbind(bo->ttm);
388 ttm_tt_destroy(bo->ttm);
397 * Will release GPU memory type usage on destruction.
398 * This is the place to put in driver specific hooks to release
399 * driver private resources.
400 * Will release the bo::reserved lock.
403 static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)
405 if (bo->bdev->driver->move_notify)
406 bo->bdev->driver->move_notify(bo, NULL);
409 ttm_tt_unbind(bo->ttm);
410 ttm_tt_destroy(bo->ttm);
413 ttm_bo_mem_put(bo, &bo->mem);
415 ww_mutex_unlock (&bo->resv->lock);
418 static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo)
420 struct reservation_object_list *fobj;
424 fobj = reservation_object_get_list(bo->resv);
425 fence = reservation_object_get_excl(bo->resv);
426 if (fence && !fence->ops->signaled)
427 fence_enable_sw_signaling(fence);
429 for (i = 0; fobj && i < fobj->shared_count; ++i) {
430 fence = rcu_dereference_protected(fobj->shared[i],
431 reservation_object_held(bo->resv));
433 if (!fence->ops->signaled)
434 fence_enable_sw_signaling(fence);
438 static void ttm_bo_cleanup_refs_or_queue(struct ttm_buffer_object *bo)
440 struct ttm_bo_device *bdev = bo->bdev;
441 struct ttm_bo_global *glob = bo->glob;
445 spin_lock(&glob->lru_lock);
446 ret = __ttm_bo_reserve(bo, false, true, false, NULL);
449 if (!ttm_bo_wait(bo, false, false, true)) {
450 put_count = ttm_bo_del_from_lru(bo);
452 spin_unlock(&glob->lru_lock);
453 ttm_bo_cleanup_memtype_use(bo);
455 ttm_bo_list_ref_sub(bo, put_count, true);
459 ttm_bo_flush_all_fences(bo);
462 * Make NO_EVICT bos immediately available to
463 * shrinkers, now that they are queued for
466 if (bo->mem.placement & TTM_PL_FLAG_NO_EVICT) {
467 bo->mem.placement &= ~TTM_PL_FLAG_NO_EVICT;
468 ttm_bo_add_to_lru(bo);
471 __ttm_bo_unreserve(bo);
474 kref_get(&bo->list_kref);
475 list_add_tail(&bo->ddestroy, &bdev->ddestroy);
476 spin_unlock(&glob->lru_lock);
478 schedule_delayed_work(&bdev->wq,
479 ((HZ / 100) < 1) ? 1 : HZ / 100);
483 * function ttm_bo_cleanup_refs_and_unlock
484 * If bo idle, remove from delayed- and lru lists, and unref.
485 * If not idle, do nothing.
487 * Must be called with lru_lock and reservation held, this function
488 * will drop both before returning.
490 * @interruptible Any sleeps should occur interruptibly.
491 * @no_wait_gpu Never wait for gpu. Return -EBUSY instead.
494 static int ttm_bo_cleanup_refs_and_unlock(struct ttm_buffer_object *bo,
498 struct ttm_bo_global *glob = bo->glob;
502 ret = ttm_bo_wait(bo, false, false, true);
504 if (ret && !no_wait_gpu) {
506 ww_mutex_unlock(&bo->resv->lock);
507 spin_unlock(&glob->lru_lock);
509 lret = reservation_object_wait_timeout_rcu(bo->resv,
519 spin_lock(&glob->lru_lock);
520 ret = __ttm_bo_reserve(bo, false, true, false, NULL);
523 * We raced, and lost, someone else holds the reservation now,
524 * and is probably busy in ttm_bo_cleanup_memtype_use.
526 * Even if it's not the case, because we finished waiting any
527 * delayed destruction would succeed, so just return success
531 spin_unlock(&glob->lru_lock);
536 * remove sync_obj with ttm_bo_wait, the wait should be
537 * finished, and no new wait object should have been added.
539 ret = ttm_bo_wait(bo, false, false, true);
543 if (ret || unlikely(list_empty(&bo->ddestroy))) {
544 __ttm_bo_unreserve(bo);
545 spin_unlock(&glob->lru_lock);
549 put_count = ttm_bo_del_from_lru(bo);
550 list_del_init(&bo->ddestroy);
553 spin_unlock(&glob->lru_lock);
554 ttm_bo_cleanup_memtype_use(bo);
556 ttm_bo_list_ref_sub(bo, put_count, true);
562 * Traverse the delayed list, and call ttm_bo_cleanup_refs on all
563 * encountered buffers.
566 static int ttm_bo_delayed_delete(struct ttm_bo_device *bdev, bool remove_all)
568 struct ttm_bo_global *glob = bdev->glob;
569 struct ttm_buffer_object *entry = NULL;
572 spin_lock(&glob->lru_lock);
573 if (list_empty(&bdev->ddestroy))
576 entry = list_first_entry(&bdev->ddestroy,
577 struct ttm_buffer_object, ddestroy);
578 kref_get(&entry->list_kref);
581 struct ttm_buffer_object *nentry = NULL;
583 if (entry->ddestroy.next != &bdev->ddestroy) {
584 nentry = list_first_entry(&entry->ddestroy,
585 struct ttm_buffer_object, ddestroy);
586 kref_get(&nentry->list_kref);
589 ret = __ttm_bo_reserve(entry, false, true, false, NULL);
590 if (remove_all && ret) {
591 spin_unlock(&glob->lru_lock);
592 ret = __ttm_bo_reserve(entry, false, false,
594 spin_lock(&glob->lru_lock);
598 ret = ttm_bo_cleanup_refs_and_unlock(entry, false,
601 spin_unlock(&glob->lru_lock);
603 kref_put(&entry->list_kref, ttm_bo_release_list);
609 spin_lock(&glob->lru_lock);
610 if (list_empty(&entry->ddestroy))
615 spin_unlock(&glob->lru_lock);
618 kref_put(&entry->list_kref, ttm_bo_release_list);
622 static void ttm_bo_delayed_workqueue(struct work_struct *work)
624 struct ttm_bo_device *bdev =
625 container_of(work, struct ttm_bo_device, wq.work);
627 if (ttm_bo_delayed_delete(bdev, false)) {
628 schedule_delayed_work(&bdev->wq,
629 ((HZ / 100) < 1) ? 1 : HZ / 100);
633 static void ttm_bo_release(struct kref *kref)
635 struct ttm_buffer_object *bo =
636 container_of(kref, struct ttm_buffer_object, kref);
637 struct ttm_bo_device *bdev = bo->bdev;
638 struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
640 drm_vma_offset_remove(&bdev->vma_manager, &bo->vma_node);
641 ttm_mem_io_lock(man, false);
642 ttm_mem_io_free_vm(bo);
643 ttm_mem_io_unlock(man);
644 ttm_bo_cleanup_refs_or_queue(bo);
645 kref_put(&bo->list_kref, ttm_bo_release_list);
648 void ttm_bo_unref(struct ttm_buffer_object **p_bo)
650 struct ttm_buffer_object *bo = *p_bo;
653 kref_put(&bo->kref, ttm_bo_release);
655 EXPORT_SYMBOL(ttm_bo_unref);
657 int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev)
659 return cancel_delayed_work_sync(&bdev->wq);
661 EXPORT_SYMBOL(ttm_bo_lock_delayed_workqueue);
663 void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched)
666 schedule_delayed_work(&bdev->wq,
667 ((HZ / 100) < 1) ? 1 : HZ / 100);
669 EXPORT_SYMBOL(ttm_bo_unlock_delayed_workqueue);
671 static int ttm_bo_evict(struct ttm_buffer_object *bo, bool interruptible,
674 struct ttm_bo_device *bdev = bo->bdev;
675 struct ttm_mem_reg evict_mem;
676 struct ttm_placement placement;
679 ret = ttm_bo_wait(bo, false, interruptible, no_wait_gpu);
681 if (unlikely(ret != 0)) {
682 if (ret != -ERESTARTSYS) {
683 pr_err("Failed to expire sync object before buffer eviction\n");
688 lockdep_assert_held(&bo->resv->lock.base);
691 evict_mem.mm_node = NULL;
692 evict_mem.bus.io_reserved_vm = false;
693 evict_mem.bus.io_reserved_count = 0;
695 placement.num_placement = 0;
696 placement.num_busy_placement = 0;
697 bdev->driver->evict_flags(bo, &placement);
698 ret = ttm_bo_mem_space(bo, &placement, &evict_mem, interruptible,
701 if (ret != -ERESTARTSYS) {
702 pr_err("Failed to find memory space for buffer 0x%p eviction\n",
704 ttm_bo_mem_space_debug(bo, &placement);
709 ret = ttm_bo_handle_move_mem(bo, &evict_mem, true, interruptible,
712 if (ret != -ERESTARTSYS)
713 pr_err("Buffer eviction failed\n");
714 ttm_bo_mem_put(bo, &evict_mem);
722 static int ttm_mem_evict_first(struct ttm_bo_device *bdev,
724 const struct ttm_place *place,
728 struct ttm_bo_global *glob = bdev->glob;
729 struct ttm_mem_type_manager *man = &bdev->man[mem_type];
730 struct ttm_buffer_object *bo;
731 int ret = -EBUSY, put_count;
733 spin_lock(&glob->lru_lock);
734 list_for_each_entry(bo, &man->lru, lru) {
735 ret = __ttm_bo_reserve(bo, false, true, false, NULL);
737 if (place && (place->fpfn || place->lpfn)) {
738 /* Don't evict this BO if it's outside of the
739 * requested placement range
741 if (place->fpfn >= (bo->mem.start + bo->mem.size) ||
742 (place->lpfn && place->lpfn <= bo->mem.start)) {
743 __ttm_bo_unreserve(bo);
754 spin_unlock(&glob->lru_lock);
758 kref_get(&bo->list_kref);
760 if (!list_empty(&bo->ddestroy)) {
761 ret = ttm_bo_cleanup_refs_and_unlock(bo, interruptible,
763 kref_put(&bo->list_kref, ttm_bo_release_list);
767 put_count = ttm_bo_del_from_lru(bo);
768 spin_unlock(&glob->lru_lock);
772 ttm_bo_list_ref_sub(bo, put_count, true);
774 ret = ttm_bo_evict(bo, interruptible, no_wait_gpu);
775 ttm_bo_unreserve(bo);
777 kref_put(&bo->list_kref, ttm_bo_release_list);
781 void ttm_bo_mem_put(struct ttm_buffer_object *bo, struct ttm_mem_reg *mem)
783 struct ttm_mem_type_manager *man = &bo->bdev->man[mem->mem_type];
786 (*man->func->put_node)(man, mem);
788 EXPORT_SYMBOL(ttm_bo_mem_put);
791 * Repeatedly evict memory from the LRU for @mem_type until we create enough
792 * space, or we've evicted everything and there isn't enough space.
794 static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
796 const struct ttm_place *place,
797 struct ttm_mem_reg *mem,
801 struct ttm_bo_device *bdev = bo->bdev;
802 struct ttm_mem_type_manager *man = &bdev->man[mem_type];
806 ret = (*man->func->get_node)(man, bo, place, mem);
807 if (unlikely(ret != 0))
811 ret = ttm_mem_evict_first(bdev, mem_type, place,
812 interruptible, no_wait_gpu);
813 if (unlikely(ret != 0))
816 if (mem->mm_node == NULL)
818 mem->mem_type = mem_type;
822 static uint32_t ttm_bo_select_caching(struct ttm_mem_type_manager *man,
823 uint32_t cur_placement,
824 uint32_t proposed_placement)
826 uint32_t caching = proposed_placement & TTM_PL_MASK_CACHING;
827 uint32_t result = proposed_placement & ~TTM_PL_MASK_CACHING;
830 * Keep current caching if possible.
833 if ((cur_placement & caching) != 0)
834 result |= (cur_placement & caching);
835 else if ((man->default_caching & caching) != 0)
836 result |= man->default_caching;
837 else if ((TTM_PL_FLAG_CACHED & caching) != 0)
838 result |= TTM_PL_FLAG_CACHED;
839 else if ((TTM_PL_FLAG_WC & caching) != 0)
840 result |= TTM_PL_FLAG_WC;
841 else if ((TTM_PL_FLAG_UNCACHED & caching) != 0)
842 result |= TTM_PL_FLAG_UNCACHED;
847 static bool ttm_bo_mt_compatible(struct ttm_mem_type_manager *man,
849 const struct ttm_place *place,
850 uint32_t *masked_placement)
852 uint32_t cur_flags = ttm_bo_type_flags(mem_type);
854 if ((cur_flags & place->flags & TTM_PL_MASK_MEM) == 0)
857 if ((place->flags & man->available_caching) == 0)
860 cur_flags |= (place->flags & man->available_caching);
862 *masked_placement = cur_flags;
867 * Creates space for memory region @mem according to its type.
869 * This function first searches for free space in compatible memory types in
870 * the priority order defined by the driver. If free space isn't found, then
871 * ttm_bo_mem_force_space is attempted in priority order to evict and find
874 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
875 struct ttm_placement *placement,
876 struct ttm_mem_reg *mem,
880 struct ttm_bo_device *bdev = bo->bdev;
881 struct ttm_mem_type_manager *man;
882 uint32_t mem_type = TTM_PL_SYSTEM;
883 uint32_t cur_flags = 0;
884 bool type_found = false;
885 bool type_ok = false;
886 bool has_erestartsys = false;
890 for (i = 0; i < placement->num_placement; ++i) {
891 const struct ttm_place *place = &placement->placement[i];
893 ret = ttm_mem_type_from_place(place, &mem_type);
896 man = &bdev->man[mem_type];
897 if (!man->has_type || !man->use_type)
900 type_ok = ttm_bo_mt_compatible(man, mem_type, place,
907 cur_flags = ttm_bo_select_caching(man, bo->mem.placement,
910 * Use the access and other non-mapping-related flag bits from
911 * the memory placement flags to the current flags
913 ttm_flag_masked(&cur_flags, place->flags,
914 ~TTM_PL_MASK_MEMTYPE);
916 if (mem_type == TTM_PL_SYSTEM)
919 ret = (*man->func->get_node)(man, bo, place, mem);
927 if ((type_ok && (mem_type == TTM_PL_SYSTEM)) || mem->mm_node) {
928 mem->mem_type = mem_type;
929 mem->placement = cur_flags;
933 for (i = 0; i < placement->num_busy_placement; ++i) {
934 const struct ttm_place *place = &placement->busy_placement[i];
936 ret = ttm_mem_type_from_place(place, &mem_type);
939 man = &bdev->man[mem_type];
940 if (!man->has_type || !man->use_type)
942 if (!ttm_bo_mt_compatible(man, mem_type, place, &cur_flags))
946 cur_flags = ttm_bo_select_caching(man, bo->mem.placement,
949 * Use the access and other non-mapping-related flag bits from
950 * the memory placement flags to the current flags
952 ttm_flag_masked(&cur_flags, place->flags,
953 ~TTM_PL_MASK_MEMTYPE);
955 if (mem_type == TTM_PL_SYSTEM) {
956 mem->mem_type = mem_type;
957 mem->placement = cur_flags;
962 ret = ttm_bo_mem_force_space(bo, mem_type, place, mem,
963 interruptible, no_wait_gpu);
964 if (ret == 0 && mem->mm_node) {
965 mem->placement = cur_flags;
968 if (ret == -ERESTARTSYS)
969 has_erestartsys = true;
973 printk(KERN_ERR TTM_PFX "No compatible memory type found.\n");
977 return (has_erestartsys) ? -ERESTARTSYS : -ENOMEM;
979 EXPORT_SYMBOL(ttm_bo_mem_space);
981 static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
982 struct ttm_placement *placement,
987 struct ttm_mem_reg mem;
989 lockdep_assert_held(&bo->resv->lock.base);
992 * FIXME: It's possible to pipeline buffer moves.
993 * Have the driver move function wait for idle when necessary,
994 * instead of doing it here.
996 ret = ttm_bo_wait(bo, false, interruptible, no_wait_gpu);
999 mem.num_pages = bo->num_pages;
1000 mem.size = mem.num_pages << PAGE_SHIFT;
1001 mem.page_alignment = bo->mem.page_alignment;
1002 mem.bus.io_reserved_vm = false;
1003 mem.bus.io_reserved_count = 0;
1005 * Determine where to move the buffer.
1007 ret = ttm_bo_mem_space(bo, placement, &mem,
1008 interruptible, no_wait_gpu);
1011 ret = ttm_bo_handle_move_mem(bo, &mem, false,
1012 interruptible, no_wait_gpu);
1014 if (ret && mem.mm_node)
1015 ttm_bo_mem_put(bo, &mem);
1019 static bool ttm_bo_mem_compat(struct ttm_placement *placement,
1020 struct ttm_mem_reg *mem,
1021 uint32_t *new_flags)
1025 for (i = 0; i < placement->num_placement; i++) {
1026 const struct ttm_place *heap = &placement->placement[i];
1028 (mem->start < heap->fpfn ||
1029 (heap->lpfn != 0 && (mem->start + mem->num_pages) > heap->lpfn)))
1032 *new_flags = heap->flags;
1033 if ((*new_flags & mem->placement & TTM_PL_MASK_CACHING) &&
1034 (*new_flags & mem->placement & TTM_PL_MASK_MEM))
1038 for (i = 0; i < placement->num_busy_placement; i++) {
1039 const struct ttm_place *heap = &placement->busy_placement[i];
1041 (mem->start < heap->fpfn ||
1042 (heap->lpfn != 0 && (mem->start + mem->num_pages) > heap->lpfn)))
1045 *new_flags = heap->flags;
1046 if ((*new_flags & mem->placement & TTM_PL_MASK_CACHING) &&
1047 (*new_flags & mem->placement & TTM_PL_MASK_MEM))
1054 int ttm_bo_validate(struct ttm_buffer_object *bo,
1055 struct ttm_placement *placement,
1062 lockdep_assert_held(&bo->resv->lock.base);
1064 * Check whether we need to move buffer.
1066 if (!ttm_bo_mem_compat(placement, &bo->mem, &new_flags)) {
1067 ret = ttm_bo_move_buffer(bo, placement, interruptible,
1073 * Use the access and other non-mapping-related flag bits from
1074 * the compatible memory placement flags to the active flags
1076 ttm_flag_masked(&bo->mem.placement, new_flags,
1077 ~TTM_PL_MASK_MEMTYPE);
1080 * We might need to add a TTM.
1082 if (bo->mem.mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {
1083 ret = ttm_bo_add_ttm(bo, true);
1089 EXPORT_SYMBOL(ttm_bo_validate);
1091 int ttm_bo_init(struct ttm_bo_device *bdev,
1092 struct ttm_buffer_object *bo,
1094 enum ttm_bo_type type,
1095 struct ttm_placement *placement,
1096 uint32_t page_alignment,
1098 struct file *persistent_swap_storage,
1100 struct sg_table *sg,
1101 struct reservation_object *resv,
1102 void (*destroy) (struct ttm_buffer_object *))
1105 unsigned long num_pages;
1106 struct ttm_mem_global *mem_glob = bdev->glob->mem_glob;
1109 ret = ttm_mem_global_alloc(mem_glob, acc_size, false, false);
1111 pr_err("Out of kernel memory\n");
1119 num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1120 if (num_pages == 0) {
1121 pr_err("Illegal buffer object size\n");
1126 ttm_mem_global_free(mem_glob, acc_size);
1129 bo->destroy = destroy;
1131 kref_init(&bo->kref);
1132 kref_init(&bo->list_kref);
1133 atomic_set(&bo->cpu_writers, 0);
1134 INIT_LIST_HEAD(&bo->lru);
1135 INIT_LIST_HEAD(&bo->ddestroy);
1136 INIT_LIST_HEAD(&bo->swap);
1137 INIT_LIST_HEAD(&bo->io_reserve_lru);
1138 mutex_init(&bo->wu_mutex);
1140 bo->glob = bdev->glob;
1142 bo->num_pages = num_pages;
1143 bo->mem.size = num_pages << PAGE_SHIFT;
1144 bo->mem.mem_type = TTM_PL_SYSTEM;
1145 bo->mem.num_pages = bo->num_pages;
1146 bo->mem.mm_node = NULL;
1147 bo->mem.page_alignment = page_alignment;
1148 bo->mem.bus.io_reserved_vm = false;
1149 bo->mem.bus.io_reserved_count = 0;
1151 bo->mem.placement = (TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED);
1152 bo->persistent_swap_storage = persistent_swap_storage;
1153 bo->acc_size = acc_size;
1157 lockdep_assert_held(&bo->resv->lock.base);
1159 bo->resv = &bo->ttm_resv;
1160 reservation_object_init(&bo->ttm_resv);
1162 atomic_inc(&bo->glob->bo_count);
1163 drm_vma_node_reset(&bo->vma_node);
1166 * For ttm_bo_type_device buffers, allocate
1167 * address space from the device.
1169 if (bo->type == ttm_bo_type_device ||
1170 bo->type == ttm_bo_type_sg)
1171 ret = drm_vma_offset_add(&bdev->vma_manager, &bo->vma_node,
1174 /* passed reservation objects should already be locked,
1175 * since otherwise lockdep will be angered in radeon.
1178 locked = ww_mutex_trylock(&bo->resv->lock);
1183 ret = ttm_bo_validate(bo, placement, interruptible, false);
1186 ttm_bo_unreserve(bo);
1188 } else if (!(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
1189 spin_lock(&bo->glob->lru_lock);
1190 ttm_bo_add_to_lru(bo);
1191 spin_unlock(&bo->glob->lru_lock);
1199 EXPORT_SYMBOL(ttm_bo_init);
1201 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
1202 unsigned long bo_size,
1203 unsigned struct_size)
1205 unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
1208 size += ttm_round_pot(struct_size);
1209 size += PAGE_ALIGN(npages * sizeof(void *));
1210 size += ttm_round_pot(sizeof(struct ttm_tt));
1213 EXPORT_SYMBOL(ttm_bo_acc_size);
1215 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
1216 unsigned long bo_size,
1217 unsigned struct_size)
1219 unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
1222 size += ttm_round_pot(struct_size);
1223 size += PAGE_ALIGN(npages * sizeof(void *));
1224 size += PAGE_ALIGN(npages * sizeof(dma_addr_t));
1225 size += ttm_round_pot(sizeof(struct ttm_dma_tt));
1228 EXPORT_SYMBOL(ttm_bo_dma_acc_size);
1230 int ttm_bo_create(struct ttm_bo_device *bdev,
1232 enum ttm_bo_type type,
1233 struct ttm_placement *placement,
1234 uint32_t page_alignment,
1236 struct file *persistent_swap_storage,
1237 struct ttm_buffer_object **p_bo)
1239 struct ttm_buffer_object *bo;
1243 bo = kzalloc(sizeof(*bo), GFP_KERNEL);
1244 if (unlikely(bo == NULL))
1247 acc_size = ttm_bo_acc_size(bdev, size, sizeof(struct ttm_buffer_object));
1248 ret = ttm_bo_init(bdev, bo, size, type, placement, page_alignment,
1249 interruptible, persistent_swap_storage, acc_size,
1251 if (likely(ret == 0))
1256 EXPORT_SYMBOL(ttm_bo_create);
1258 static int ttm_bo_force_list_clean(struct ttm_bo_device *bdev,
1259 unsigned mem_type, bool allow_errors)
1261 struct ttm_mem_type_manager *man = &bdev->man[mem_type];
1262 struct ttm_bo_global *glob = bdev->glob;
1266 * Can't use standard list traversal since we're unlocking.
1269 spin_lock(&glob->lru_lock);
1270 while (!list_empty(&man->lru)) {
1271 spin_unlock(&glob->lru_lock);
1272 ret = ttm_mem_evict_first(bdev, mem_type, NULL, false, false);
1277 pr_err("Cleanup eviction failed\n");
1280 spin_lock(&glob->lru_lock);
1282 spin_unlock(&glob->lru_lock);
1286 int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type)
1288 struct ttm_mem_type_manager *man;
1291 if (mem_type >= TTM_NUM_MEM_TYPES) {
1292 pr_err("Illegal memory type %d\n", mem_type);
1295 man = &bdev->man[mem_type];
1297 if (!man->has_type) {
1298 pr_err("Trying to take down uninitialized memory manager type %u\n",
1303 man->use_type = false;
1304 man->has_type = false;
1308 ttm_bo_force_list_clean(bdev, mem_type, false);
1310 ret = (*man->func->takedown)(man);
1315 EXPORT_SYMBOL(ttm_bo_clean_mm);
1317 int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type)
1319 struct ttm_mem_type_manager *man = &bdev->man[mem_type];
1321 if (mem_type == 0 || mem_type >= TTM_NUM_MEM_TYPES) {
1322 pr_err("Illegal memory manager memory type %u\n", mem_type);
1326 if (!man->has_type) {
1327 pr_err("Memory type %u has not been initialized\n", mem_type);
1331 return ttm_bo_force_list_clean(bdev, mem_type, true);
1333 EXPORT_SYMBOL(ttm_bo_evict_mm);
1335 int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
1336 unsigned long p_size)
1339 struct ttm_mem_type_manager *man;
1341 BUG_ON(type >= TTM_NUM_MEM_TYPES);
1342 man = &bdev->man[type];
1343 BUG_ON(man->has_type);
1344 man->io_reserve_fastpath = true;
1345 man->use_io_reserve_lru = false;
1346 mutex_init(&man->io_reserve_mutex);
1347 INIT_LIST_HEAD(&man->io_reserve_lru);
1349 ret = bdev->driver->init_mem_type(bdev, type, man);
1355 if (type != TTM_PL_SYSTEM) {
1356 ret = (*man->func->init)(man, p_size);
1360 man->has_type = true;
1361 man->use_type = true;
1364 INIT_LIST_HEAD(&man->lru);
1368 EXPORT_SYMBOL(ttm_bo_init_mm);
1370 static void ttm_bo_global_kobj_release(struct kobject *kobj)
1372 struct ttm_bo_global *glob =
1373 container_of(kobj, struct ttm_bo_global, kobj);
1375 ttm_mem_unregister_shrink(glob->mem_glob, &glob->shrink);
1376 __free_page(glob->dummy_read_page);
1380 void ttm_bo_global_release(struct drm_global_reference *ref)
1382 struct ttm_bo_global *glob = ref->object;
1384 kobject_del(&glob->kobj);
1385 kobject_put(&glob->kobj);
1387 EXPORT_SYMBOL(ttm_bo_global_release);
1389 int ttm_bo_global_init(struct drm_global_reference *ref)
1391 struct ttm_bo_global_ref *bo_ref =
1392 container_of(ref, struct ttm_bo_global_ref, ref);
1393 struct ttm_bo_global *glob = ref->object;
1396 mutex_init(&glob->device_list_mutex);
1397 spin_lock_init(&glob->lru_lock);
1398 glob->mem_glob = bo_ref->mem_glob;
1399 glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32);
1401 if (unlikely(glob->dummy_read_page == NULL)) {
1406 INIT_LIST_HEAD(&glob->swap_lru);
1407 INIT_LIST_HEAD(&glob->device_list);
1409 ttm_mem_init_shrink(&glob->shrink, ttm_bo_swapout);
1410 ret = ttm_mem_register_shrink(glob->mem_glob, &glob->shrink);
1411 if (unlikely(ret != 0)) {
1412 pr_err("Could not register buffer object swapout\n");
1416 atomic_set(&glob->bo_count, 0);
1418 ret = kobject_init_and_add(
1419 &glob->kobj, &ttm_bo_glob_kobj_type, ttm_get_kobj(), "buffer_objects");
1420 if (unlikely(ret != 0))
1421 kobject_put(&glob->kobj);
1424 __free_page(glob->dummy_read_page);
1429 EXPORT_SYMBOL(ttm_bo_global_init);
1432 int ttm_bo_device_release(struct ttm_bo_device *bdev)
1435 unsigned i = TTM_NUM_MEM_TYPES;
1436 struct ttm_mem_type_manager *man;
1437 struct ttm_bo_global *glob = bdev->glob;
1440 man = &bdev->man[i];
1441 if (man->has_type) {
1442 man->use_type = false;
1443 if ((i != TTM_PL_SYSTEM) && ttm_bo_clean_mm(bdev, i)) {
1445 pr_err("DRM memory manager type %d is not clean\n",
1448 man->has_type = false;
1452 mutex_lock(&glob->device_list_mutex);
1453 list_del(&bdev->device_list);
1454 mutex_unlock(&glob->device_list_mutex);
1456 cancel_delayed_work_sync(&bdev->wq);
1458 while (ttm_bo_delayed_delete(bdev, true))
1461 spin_lock(&glob->lru_lock);
1462 if (list_empty(&bdev->ddestroy))
1463 TTM_DEBUG("Delayed destroy list was clean\n");
1465 if (list_empty(&bdev->man[0].lru))
1466 TTM_DEBUG("Swap list was clean\n");
1467 spin_unlock(&glob->lru_lock);
1469 drm_vma_offset_manager_destroy(&bdev->vma_manager);
1473 EXPORT_SYMBOL(ttm_bo_device_release);
1475 int ttm_bo_device_init(struct ttm_bo_device *bdev,
1476 struct ttm_bo_global *glob,
1477 struct ttm_bo_driver *driver,
1478 struct address_space *mapping,
1479 uint64_t file_page_offset,
1484 bdev->driver = driver;
1486 memset(bdev->man, 0, sizeof(bdev->man));
1489 * Initialize the system memory buffer type.
1490 * Other types need to be driver / IOCTL initialized.
1492 ret = ttm_bo_init_mm(bdev, TTM_PL_SYSTEM, 0);
1493 if (unlikely(ret != 0))
1496 drm_vma_offset_manager_init(&bdev->vma_manager, file_page_offset,
1498 INIT_DELAYED_WORK(&bdev->wq, ttm_bo_delayed_workqueue);
1499 INIT_LIST_HEAD(&bdev->ddestroy);
1500 bdev->dev_mapping = mapping;
1502 bdev->need_dma32 = need_dma32;
1504 mutex_lock(&glob->device_list_mutex);
1505 list_add_tail(&bdev->device_list, &glob->device_list);
1506 mutex_unlock(&glob->device_list_mutex);
1512 EXPORT_SYMBOL(ttm_bo_device_init);
1515 * buffer object vm functions.
1518 bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem)
1520 struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
1522 if (!(man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
1523 if (mem->mem_type == TTM_PL_SYSTEM)
1526 if (man->flags & TTM_MEMTYPE_FLAG_CMA)
1529 if (mem->placement & TTM_PL_FLAG_CACHED)
1535 void ttm_bo_unmap_virtual_locked(struct ttm_buffer_object *bo)
1537 struct ttm_bo_device *bdev = bo->bdev;
1539 drm_vma_node_unmap(&bo->vma_node, bdev->dev_mapping);
1540 ttm_mem_io_free_vm(bo);
1543 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo)
1545 struct ttm_bo_device *bdev = bo->bdev;
1546 struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
1548 ttm_mem_io_lock(man, false);
1549 ttm_bo_unmap_virtual_locked(bo);
1550 ttm_mem_io_unlock(man);
1554 EXPORT_SYMBOL(ttm_bo_unmap_virtual);
1556 int ttm_bo_wait(struct ttm_buffer_object *bo,
1557 bool lazy, bool interruptible, bool no_wait)
1559 struct reservation_object_list *fobj;
1560 struct reservation_object *resv;
1562 long timeout = 15 * HZ;
1566 fobj = reservation_object_get_list(resv);
1567 excl = reservation_object_get_excl(resv);
1569 if (!fence_is_signaled(excl)) {
1573 timeout = fence_wait_timeout(excl,
1574 interruptible, timeout);
1578 for (i = 0; fobj && timeout > 0 && i < fobj->shared_count; ++i) {
1579 struct fence *fence;
1580 fence = rcu_dereference_protected(fobj->shared[i],
1581 reservation_object_held(resv));
1583 if (!fence_is_signaled(fence)) {
1587 timeout = fence_wait_timeout(fence,
1588 interruptible, timeout);
1598 reservation_object_add_excl_fence(resv, NULL);
1599 clear_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags);
1602 EXPORT_SYMBOL(ttm_bo_wait);
1604 int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait)
1609 * Using ttm_bo_reserve makes sure the lru lists are updated.
1612 ret = ttm_bo_reserve(bo, true, no_wait, false, NULL);
1613 if (unlikely(ret != 0))
1615 ret = ttm_bo_wait(bo, false, true, no_wait);
1616 if (likely(ret == 0))
1617 atomic_inc(&bo->cpu_writers);
1618 ttm_bo_unreserve(bo);
1621 EXPORT_SYMBOL(ttm_bo_synccpu_write_grab);
1623 void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo)
1625 atomic_dec(&bo->cpu_writers);
1627 EXPORT_SYMBOL(ttm_bo_synccpu_write_release);
1630 * A buffer object shrink method that tries to swap out the first
1631 * buffer object on the bo_global::swap_lru list.
1634 static int ttm_bo_swapout(struct ttm_mem_shrink *shrink)
1636 struct ttm_bo_global *glob =
1637 container_of(shrink, struct ttm_bo_global, shrink);
1638 struct ttm_buffer_object *bo;
1641 uint32_t swap_placement = (TTM_PL_FLAG_CACHED | TTM_PL_FLAG_SYSTEM);
1643 spin_lock(&glob->lru_lock);
1644 list_for_each_entry(bo, &glob->swap_lru, swap) {
1645 ret = __ttm_bo_reserve(bo, false, true, false, NULL);
1651 spin_unlock(&glob->lru_lock);
1655 kref_get(&bo->list_kref);
1657 if (!list_empty(&bo->ddestroy)) {
1658 ret = ttm_bo_cleanup_refs_and_unlock(bo, false, false);
1659 kref_put(&bo->list_kref, ttm_bo_release_list);
1663 put_count = ttm_bo_del_from_lru(bo);
1664 spin_unlock(&glob->lru_lock);
1666 ttm_bo_list_ref_sub(bo, put_count, true);
1669 * Wait for GPU, then move to system cached.
1672 ret = ttm_bo_wait(bo, false, false, false);
1674 if (unlikely(ret != 0))
1677 if ((bo->mem.placement & swap_placement) != swap_placement) {
1678 struct ttm_mem_reg evict_mem;
1680 evict_mem = bo->mem;
1681 evict_mem.mm_node = NULL;
1682 evict_mem.placement = TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED;
1683 evict_mem.mem_type = TTM_PL_SYSTEM;
1685 ret = ttm_bo_handle_move_mem(bo, &evict_mem, true,
1687 if (unlikely(ret != 0))
1691 ttm_bo_unmap_virtual(bo);
1694 * Swap out. Buffer will be swapped in again as soon as
1695 * anyone tries to access a ttm page.
1698 if (bo->bdev->driver->swap_notify)
1699 bo->bdev->driver->swap_notify(bo);
1701 ret = ttm_tt_swapout(bo->ttm, bo->persistent_swap_storage);
1706 * Unreserve without putting on LRU to avoid swapping out an
1707 * already swapped buffer.
1710 __ttm_bo_unreserve(bo);
1711 kref_put(&bo->list_kref, ttm_bo_release_list);
1715 void ttm_bo_swapout_all(struct ttm_bo_device *bdev)
1717 while (ttm_bo_swapout(&bdev->glob->shrink) == 0)
1720 EXPORT_SYMBOL(ttm_bo_swapout_all);
1723 * ttm_bo_wait_unreserved - interruptible wait for a buffer object to become
1726 * @bo: Pointer to buffer
1728 int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo)
1733 * In the absense of a wait_unlocked API,
1734 * Use the bo::wu_mutex to avoid triggering livelocks due to
1735 * concurrent use of this function. Note that this use of
1736 * bo::wu_mutex can go away if we change locking order to
1737 * mmap_sem -> bo::reserve.
1739 ret = mutex_lock_interruptible(&bo->wu_mutex);
1740 if (unlikely(ret != 0))
1741 return -ERESTARTSYS;
1742 if (!ww_mutex_is_locked(&bo->resv->lock))
1744 ret = __ttm_bo_reserve(bo, true, false, false, NULL);
1745 if (unlikely(ret != 0))
1747 __ttm_bo_unreserve(bo);
1750 mutex_unlock(&bo->wu_mutex);