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ttm_bo.c revision 1.1
      1 /**************************************************************************
      2  *
      3  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
      4  * All Rights Reserved.
      5  *
      6  * Permission is hereby granted, free of charge, to any person obtaining a
      7  * copy of this software and associated documentation files (the
      8  * "Software"), to deal in the Software without restriction, including
      9  * without limitation the rights to use, copy, modify, merge, publish,
     10  * distribute, sub license, and/or sell copies of the Software, and to
     11  * permit persons to whom the Software is furnished to do so, subject to
     12  * the following conditions:
     13  *
     14  * The above copyright notice and this permission notice (including the
     15  * next paragraph) shall be included in all copies or substantial portions
     16  * of the Software.
     17  *
     18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
     21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
     22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
     23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
     24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
     25  *
     26  **************************************************************************/
     27 /*
     28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
     29  */
     30 
     31 #define pr_fmt(fmt) "[TTM] " fmt
     32 
     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>
     39 #include <linux/mm.h>
     40 #include <linux/file.h>
     41 #include <linux/module.h>
     42 #include <linux/atomic.h>
     43 
     44 #define TTM_ASSERT_LOCKED(param)
     45 #define TTM_DEBUG(fmt, arg...)
     46 #define TTM_BO_HASH_ORDER 13
     47 
     48 static int ttm_bo_setup_vm(struct ttm_buffer_object *bo);
     49 static int ttm_bo_swapout(struct ttm_mem_shrink *shrink);
     50 static void ttm_bo_global_kobj_release(struct kobject *kobj);
     51 
     52 static struct attribute ttm_bo_count = {
     53 	.name = "bo_count",
     54 	.mode = S_IRUGO
     55 };
     56 
     57 static inline int ttm_mem_type_from_flags(uint32_t flags, uint32_t *mem_type)
     58 {
     59 	int i;
     60 
     61 	for (i = 0; i <= TTM_PL_PRIV5; i++)
     62 		if (flags & (1 << i)) {
     63 			*mem_type = i;
     64 			return 0;
     65 		}
     66 	return -EINVAL;
     67 }
     68 
     69 static void ttm_mem_type_debug(struct ttm_bo_device *bdev, int mem_type)
     70 {
     71 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
     72 
     73 	pr_err("    has_type: %d\n", man->has_type);
     74 	pr_err("    use_type: %d\n", man->use_type);
     75 	pr_err("    flags: 0x%08X\n", man->flags);
     76 	pr_err("    gpu_offset: 0x%08lX\n", man->gpu_offset);
     77 	pr_err("    size: %llu\n", man->size);
     78 	pr_err("    available_caching: 0x%08X\n", man->available_caching);
     79 	pr_err("    default_caching: 0x%08X\n", man->default_caching);
     80 	if (mem_type != TTM_PL_SYSTEM)
     81 		(*man->func->debug)(man, TTM_PFX);
     82 }
     83 
     84 static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
     85 					struct ttm_placement *placement)
     86 {
     87 	int i, ret, mem_type;
     88 
     89 	pr_err("No space for %p (%lu pages, %luK, %luM)\n",
     90 	       bo, bo->mem.num_pages, bo->mem.size >> 10,
     91 	       bo->mem.size >> 20);
     92 	for (i = 0; i < placement->num_placement; i++) {
     93 		ret = ttm_mem_type_from_flags(placement->placement[i],
     94 						&mem_type);
     95 		if (ret)
     96 			return;
     97 		pr_err("  placement[%d]=0x%08X (%d)\n",
     98 		       i, placement->placement[i], mem_type);
     99 		ttm_mem_type_debug(bo->bdev, mem_type);
    100 	}
    101 }
    102 
    103 static ssize_t ttm_bo_global_show(struct kobject *kobj,
    104 				  struct attribute *attr,
    105 				  char *buffer)
    106 {
    107 	struct ttm_bo_global *glob =
    108 		container_of(kobj, struct ttm_bo_global, kobj);
    109 
    110 	return snprintf(buffer, PAGE_SIZE, "%lu\n",
    111 			(unsigned long) atomic_read(&glob->bo_count));
    112 }
    113 
    114 static struct attribute *ttm_bo_global_attrs[] = {
    115 	&ttm_bo_count,
    116 	NULL
    117 };
    118 
    119 static const struct sysfs_ops ttm_bo_global_ops = {
    120 	.show = &ttm_bo_global_show
    121 };
    122 
    123 static struct kobj_type ttm_bo_glob_kobj_type  = {
    124 	.release = &ttm_bo_global_kobj_release,
    125 	.sysfs_ops = &ttm_bo_global_ops,
    126 	.default_attrs = ttm_bo_global_attrs
    127 };
    128 
    129 
    130 static inline uint32_t ttm_bo_type_flags(unsigned type)
    131 {
    132 	return 1 << (type);
    133 }
    134 
    135 static void ttm_bo_release_list(struct kref *list_kref)
    136 {
    137 	struct ttm_buffer_object *bo =
    138 	    container_of(list_kref, struct ttm_buffer_object, list_kref);
    139 	struct ttm_bo_device *bdev = bo->bdev;
    140 	size_t acc_size = bo->acc_size;
    141 
    142 	BUG_ON(atomic_read(&bo->list_kref.refcount));
    143 	BUG_ON(atomic_read(&bo->kref.refcount));
    144 	BUG_ON(atomic_read(&bo->cpu_writers));
    145 	BUG_ON(bo->sync_obj != NULL);
    146 	BUG_ON(bo->mem.mm_node != NULL);
    147 	BUG_ON(!list_empty(&bo->lru));
    148 	BUG_ON(!list_empty(&bo->ddestroy));
    149 
    150 	if (bo->ttm)
    151 		ttm_tt_destroy(bo->ttm);
    152 	atomic_dec(&bo->glob->bo_count);
    153 	if (bo->destroy)
    154 		bo->destroy(bo);
    155 	else {
    156 		kfree(bo);
    157 	}
    158 	ttm_mem_global_free(bdev->glob->mem_glob, acc_size);
    159 }
    160 
    161 int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo, bool interruptible)
    162 {
    163 	if (interruptible) {
    164 		return wait_event_interruptible(bo->event_queue,
    165 					       !ttm_bo_is_reserved(bo));
    166 	} else {
    167 		wait_event(bo->event_queue, !ttm_bo_is_reserved(bo));
    168 		return 0;
    169 	}
    170 }
    171 EXPORT_SYMBOL(ttm_bo_wait_unreserved);
    172 
    173 void ttm_bo_add_to_lru(struct ttm_buffer_object *bo)
    174 {
    175 	struct ttm_bo_device *bdev = bo->bdev;
    176 	struct ttm_mem_type_manager *man;
    177 
    178 	BUG_ON(!ttm_bo_is_reserved(bo));
    179 
    180 	if (!(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
    181 
    182 		BUG_ON(!list_empty(&bo->lru));
    183 
    184 		man = &bdev->man[bo->mem.mem_type];
    185 		list_add_tail(&bo->lru, &man->lru);
    186 		kref_get(&bo->list_kref);
    187 
    188 		if (bo->ttm != NULL) {
    189 			list_add_tail(&bo->swap, &bo->glob->swap_lru);
    190 			kref_get(&bo->list_kref);
    191 		}
    192 	}
    193 }
    194 
    195 int ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
    196 {
    197 	int put_count = 0;
    198 
    199 	if (!list_empty(&bo->swap)) {
    200 		list_del_init(&bo->swap);
    201 		++put_count;
    202 	}
    203 	if (!list_empty(&bo->lru)) {
    204 		list_del_init(&bo->lru);
    205 		++put_count;
    206 	}
    207 
    208 	/*
    209 	 * TODO: Add a driver hook to delete from
    210 	 * driver-specific LRU's here.
    211 	 */
    212 
    213 	return put_count;
    214 }
    215 
    216 int ttm_bo_reserve_locked(struct ttm_buffer_object *bo,
    217 			  bool interruptible,
    218 			  bool no_wait, bool use_sequence, uint32_t sequence)
    219 {
    220 	struct ttm_bo_global *glob = bo->glob;
    221 	int ret;
    222 
    223 	while (unlikely(atomic_read(&bo->reserved) != 0)) {
    224 		/**
    225 		 * Deadlock avoidance for multi-bo reserving.
    226 		 */
    227 		if (use_sequence && bo->seq_valid) {
    228 			/**
    229 			 * We've already reserved this one.
    230 			 */
    231 			if (unlikely(sequence == bo->val_seq))
    232 				return -EDEADLK;
    233 			/**
    234 			 * Already reserved by a thread that will not back
    235 			 * off for us. We need to back off.
    236 			 */
    237 			if (unlikely(sequence - bo->val_seq < (1 << 31)))
    238 				return -EAGAIN;
    239 		}
    240 
    241 		if (no_wait)
    242 			return -EBUSY;
    243 
    244 		spin_unlock(&glob->lru_lock);
    245 		ret = ttm_bo_wait_unreserved(bo, interruptible);
    246 		spin_lock(&glob->lru_lock);
    247 
    248 		if (unlikely(ret))
    249 			return ret;
    250 	}
    251 
    252 	atomic_set(&bo->reserved, 1);
    253 	if (use_sequence) {
    254 		/**
    255 		 * Wake up waiters that may need to recheck for deadlock,
    256 		 * if we decreased the sequence number.
    257 		 */
    258 		if (unlikely((bo->val_seq - sequence < (1 << 31))
    259 			     || !bo->seq_valid))
    260 			wake_up_all(&bo->event_queue);
    261 
    262 		bo->val_seq = sequence;
    263 		bo->seq_valid = true;
    264 	} else {
    265 		bo->seq_valid = false;
    266 	}
    267 
    268 	return 0;
    269 }
    270 EXPORT_SYMBOL(ttm_bo_reserve);
    271 
    272 static void ttm_bo_ref_bug(struct kref *list_kref)
    273 {
    274 	BUG();
    275 }
    276 
    277 void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count,
    278 			 bool never_free)
    279 {
    280 	kref_sub(&bo->list_kref, count,
    281 		 (never_free) ? ttm_bo_ref_bug : ttm_bo_release_list);
    282 }
    283 
    284 int ttm_bo_reserve(struct ttm_buffer_object *bo,
    285 		   bool interruptible,
    286 		   bool no_wait, bool use_sequence, uint32_t sequence)
    287 {
    288 	struct ttm_bo_global *glob = bo->glob;
    289 	int put_count = 0;
    290 	int ret;
    291 
    292 	spin_lock(&glob->lru_lock);
    293 	ret = ttm_bo_reserve_locked(bo, interruptible, no_wait, use_sequence,
    294 				    sequence);
    295 	if (likely(ret == 0))
    296 		put_count = ttm_bo_del_from_lru(bo);
    297 	spin_unlock(&glob->lru_lock);
    298 
    299 	ttm_bo_list_ref_sub(bo, put_count, true);
    300 
    301 	return ret;
    302 }
    303 
    304 void ttm_bo_unreserve_locked(struct ttm_buffer_object *bo)
    305 {
    306 	ttm_bo_add_to_lru(bo);
    307 	atomic_set(&bo->reserved, 0);
    308 	wake_up_all(&bo->event_queue);
    309 }
    310 
    311 void ttm_bo_unreserve(struct ttm_buffer_object *bo)
    312 {
    313 	struct ttm_bo_global *glob = bo->glob;
    314 
    315 	spin_lock(&glob->lru_lock);
    316 	ttm_bo_unreserve_locked(bo);
    317 	spin_unlock(&glob->lru_lock);
    318 }
    319 EXPORT_SYMBOL(ttm_bo_unreserve);
    320 
    321 /*
    322  * Call bo->mutex locked.
    323  */
    324 static int ttm_bo_add_ttm(struct ttm_buffer_object *bo, bool zero_alloc)
    325 {
    326 	struct ttm_bo_device *bdev = bo->bdev;
    327 	struct ttm_bo_global *glob = bo->glob;
    328 	int ret = 0;
    329 	uint32_t page_flags = 0;
    330 
    331 	TTM_ASSERT_LOCKED(&bo->mutex);
    332 	bo->ttm = NULL;
    333 
    334 	if (bdev->need_dma32)
    335 		page_flags |= TTM_PAGE_FLAG_DMA32;
    336 
    337 	switch (bo->type) {
    338 	case ttm_bo_type_device:
    339 		if (zero_alloc)
    340 			page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
    341 	case ttm_bo_type_kernel:
    342 		bo->ttm = bdev->driver->ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,
    343 						      page_flags, glob->dummy_read_page);
    344 		if (unlikely(bo->ttm == NULL))
    345 			ret = -ENOMEM;
    346 		break;
    347 	case ttm_bo_type_sg:
    348 		bo->ttm = bdev->driver->ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,
    349 						      page_flags | TTM_PAGE_FLAG_SG,
    350 						      glob->dummy_read_page);
    351 		if (unlikely(bo->ttm == NULL)) {
    352 			ret = -ENOMEM;
    353 			break;
    354 		}
    355 		bo->ttm->sg = bo->sg;
    356 		break;
    357 	default:
    358 		pr_err("Illegal buffer object type\n");
    359 		ret = -EINVAL;
    360 		break;
    361 	}
    362 
    363 	return ret;
    364 }
    365 
    366 static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
    367 				  struct ttm_mem_reg *mem,
    368 				  bool evict, bool interruptible,
    369 				  bool no_wait_gpu)
    370 {
    371 	struct ttm_bo_device *bdev = bo->bdev;
    372 	bool old_is_pci = ttm_mem_reg_is_pci(bdev, &bo->mem);
    373 	bool new_is_pci = ttm_mem_reg_is_pci(bdev, mem);
    374 	struct ttm_mem_type_manager *old_man = &bdev->man[bo->mem.mem_type];
    375 	struct ttm_mem_type_manager *new_man = &bdev->man[mem->mem_type];
    376 	int ret = 0;
    377 
    378 	if (old_is_pci || new_is_pci ||
    379 	    ((mem->placement & bo->mem.placement & TTM_PL_MASK_CACHING) == 0)) {
    380 		ret = ttm_mem_io_lock(old_man, true);
    381 		if (unlikely(ret != 0))
    382 			goto out_err;
    383 		ttm_bo_unmap_virtual_locked(bo);
    384 		ttm_mem_io_unlock(old_man);
    385 	}
    386 
    387 	/*
    388 	 * Create and bind a ttm if required.
    389 	 */
    390 
    391 	if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
    392 		if (bo->ttm == NULL) {
    393 			bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);
    394 			ret = ttm_bo_add_ttm(bo, zero);
    395 			if (ret)
    396 				goto out_err;
    397 		}
    398 
    399 		ret = ttm_tt_set_placement_caching(bo->ttm, mem->placement);
    400 		if (ret)
    401 			goto out_err;
    402 
    403 		if (mem->mem_type != TTM_PL_SYSTEM) {
    404 			ret = ttm_tt_bind(bo->ttm, mem);
    405 			if (ret)
    406 				goto out_err;
    407 		}
    408 
    409 		if (bo->mem.mem_type == TTM_PL_SYSTEM) {
    410 			if (bdev->driver->move_notify)
    411 				bdev->driver->move_notify(bo, mem);
    412 			bo->mem = *mem;
    413 			mem->mm_node = NULL;
    414 			goto moved;
    415 		}
    416 	}
    417 
    418 	if (bdev->driver->move_notify)
    419 		bdev->driver->move_notify(bo, mem);
    420 
    421 	if (!(old_man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
    422 	    !(new_man->flags & TTM_MEMTYPE_FLAG_FIXED))
    423 		ret = ttm_bo_move_ttm(bo, evict, no_wait_gpu, mem);
    424 	else if (bdev->driver->move)
    425 		ret = bdev->driver->move(bo, evict, interruptible,
    426 					 no_wait_gpu, mem);
    427 	else
    428 		ret = ttm_bo_move_memcpy(bo, evict, no_wait_gpu, mem);
    429 
    430 	if (ret) {
    431 		if (bdev->driver->move_notify) {
    432 			struct ttm_mem_reg tmp_mem = *mem;
    433 			*mem = bo->mem;
    434 			bo->mem = tmp_mem;
    435 			bdev->driver->move_notify(bo, mem);
    436 			bo->mem = *mem;
    437 			*mem = tmp_mem;
    438 		}
    439 
    440 		goto out_err;
    441 	}
    442 
    443 moved:
    444 	if (bo->evicted) {
    445 		ret = bdev->driver->invalidate_caches(bdev, bo->mem.placement);
    446 		if (ret)
    447 			pr_err("Can not flush read caches\n");
    448 		bo->evicted = false;
    449 	}
    450 
    451 	if (bo->mem.mm_node) {
    452 		bo->offset = (bo->mem.start << PAGE_SHIFT) +
    453 		    bdev->man[bo->mem.mem_type].gpu_offset;
    454 		bo->cur_placement = bo->mem.placement;
    455 	} else
    456 		bo->offset = 0;
    457 
    458 	return 0;
    459 
    460 out_err:
    461 	new_man = &bdev->man[bo->mem.mem_type];
    462 	if ((new_man->flags & TTM_MEMTYPE_FLAG_FIXED) && bo->ttm) {
    463 		ttm_tt_unbind(bo->ttm);
    464 		ttm_tt_destroy(bo->ttm);
    465 		bo->ttm = NULL;
    466 	}
    467 
    468 	return ret;
    469 }
    470 
    471 /**
    472  * Call bo::reserved.
    473  * Will release GPU memory type usage on destruction.
    474  * This is the place to put in driver specific hooks to release
    475  * driver private resources.
    476  * Will release the bo::reserved lock.
    477  */
    478 
    479 static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)
    480 {
    481 	if (bo->bdev->driver->move_notify)
    482 		bo->bdev->driver->move_notify(bo, NULL);
    483 
    484 	if (bo->ttm) {
    485 		ttm_tt_unbind(bo->ttm);
    486 		ttm_tt_destroy(bo->ttm);
    487 		bo->ttm = NULL;
    488 	}
    489 	ttm_bo_mem_put(bo, &bo->mem);
    490 
    491 	atomic_set(&bo->reserved, 0);
    492 	wake_up_all(&bo->event_queue);
    493 
    494 	/*
    495 	 * Since the final reference to this bo may not be dropped by
    496 	 * the current task we have to put a memory barrier here to make
    497 	 * sure the changes done in this function are always visible.
    498 	 *
    499 	 * This function only needs protection against the final kref_put.
    500 	 */
    501 	smp_mb__before_atomic_dec();
    502 }
    503 
    504 static void ttm_bo_cleanup_refs_or_queue(struct ttm_buffer_object *bo)
    505 {
    506 	struct ttm_bo_device *bdev = bo->bdev;
    507 	struct ttm_bo_global *glob = bo->glob;
    508 	struct ttm_bo_driver *driver = bdev->driver;
    509 	void *sync_obj = NULL;
    510 	int put_count;
    511 	int ret;
    512 
    513 	spin_lock(&glob->lru_lock);
    514 	ret = ttm_bo_reserve_locked(bo, false, true, false, 0);
    515 
    516 	spin_lock(&bdev->fence_lock);
    517 	(void) ttm_bo_wait(bo, false, false, true);
    518 	if (!ret && !bo->sync_obj) {
    519 		spin_unlock(&bdev->fence_lock);
    520 		put_count = ttm_bo_del_from_lru(bo);
    521 
    522 		spin_unlock(&glob->lru_lock);
    523 		ttm_bo_cleanup_memtype_use(bo);
    524 
    525 		ttm_bo_list_ref_sub(bo, put_count, true);
    526 
    527 		return;
    528 	}
    529 	if (bo->sync_obj)
    530 		sync_obj = driver->sync_obj_ref(bo->sync_obj);
    531 	spin_unlock(&bdev->fence_lock);
    532 
    533 	if (!ret) {
    534 		atomic_set(&bo->reserved, 0);
    535 		wake_up_all(&bo->event_queue);
    536 	}
    537 
    538 	kref_get(&bo->list_kref);
    539 	list_add_tail(&bo->ddestroy, &bdev->ddestroy);
    540 	spin_unlock(&glob->lru_lock);
    541 
    542 	if (sync_obj) {
    543 		driver->sync_obj_flush(sync_obj);
    544 		driver->sync_obj_unref(&sync_obj);
    545 	}
    546 	schedule_delayed_work(&bdev->wq,
    547 			      ((HZ / 100) < 1) ? 1 : HZ / 100);
    548 }
    549 
    550 /**
    551  * function ttm_bo_cleanup_refs_and_unlock
    552  * If bo idle, remove from delayed- and lru lists, and unref.
    553  * If not idle, do nothing.
    554  *
    555  * Must be called with lru_lock and reservation held, this function
    556  * will drop both before returning.
    557  *
    558  * @interruptible         Any sleeps should occur interruptibly.
    559  * @no_wait_gpu           Never wait for gpu. Return -EBUSY instead.
    560  */
    561 
    562 static int ttm_bo_cleanup_refs_and_unlock(struct ttm_buffer_object *bo,
    563 					  bool interruptible,
    564 					  bool no_wait_gpu)
    565 {
    566 	struct ttm_bo_device *bdev = bo->bdev;
    567 	struct ttm_bo_driver *driver = bdev->driver;
    568 	struct ttm_bo_global *glob = bo->glob;
    569 	int put_count;
    570 	int ret;
    571 
    572 	spin_lock(&bdev->fence_lock);
    573 	ret = ttm_bo_wait(bo, false, false, true);
    574 
    575 	if (ret && !no_wait_gpu) {
    576 		void *sync_obj;
    577 
    578 		/*
    579 		 * Take a reference to the fence and unreserve,
    580 		 * at this point the buffer should be dead, so
    581 		 * no new sync objects can be attached.
    582 		 */
    583 		sync_obj = driver->sync_obj_ref(bo->sync_obj);
    584 		spin_unlock(&bdev->fence_lock);
    585 
    586 		atomic_set(&bo->reserved, 0);
    587 		wake_up_all(&bo->event_queue);
    588 		spin_unlock(&glob->lru_lock);
    589 
    590 		ret = driver->sync_obj_wait(sync_obj, false, interruptible);
    591 		driver->sync_obj_unref(&sync_obj);
    592 		if (ret)
    593 			return ret;
    594 
    595 		/*
    596 		 * remove sync_obj with ttm_bo_wait, the wait should be
    597 		 * finished, and no new wait object should have been added.
    598 		 */
    599 		spin_lock(&bdev->fence_lock);
    600 		ret = ttm_bo_wait(bo, false, false, true);
    601 		WARN_ON(ret);
    602 		spin_unlock(&bdev->fence_lock);
    603 		if (ret)
    604 			return ret;
    605 
    606 		spin_lock(&glob->lru_lock);
    607 		ret = ttm_bo_reserve_locked(bo, false, true, false, 0);
    608 
    609 		/*
    610 		 * We raced, and lost, someone else holds the reservation now,
    611 		 * and is probably busy in ttm_bo_cleanup_memtype_use.
    612 		 *
    613 		 * Even if it's not the case, because we finished waiting any
    614 		 * delayed destruction would succeed, so just return success
    615 		 * here.
    616 		 */
    617 		if (ret) {
    618 			spin_unlock(&glob->lru_lock);
    619 			return 0;
    620 		}
    621 	} else
    622 		spin_unlock(&bdev->fence_lock);
    623 
    624 	if (ret || unlikely(list_empty(&bo->ddestroy))) {
    625 		atomic_set(&bo->reserved, 0);
    626 		wake_up_all(&bo->event_queue);
    627 		spin_unlock(&glob->lru_lock);
    628 		return ret;
    629 	}
    630 
    631 	put_count = ttm_bo_del_from_lru(bo);
    632 	list_del_init(&bo->ddestroy);
    633 	++put_count;
    634 
    635 	spin_unlock(&glob->lru_lock);
    636 	ttm_bo_cleanup_memtype_use(bo);
    637 
    638 	ttm_bo_list_ref_sub(bo, put_count, true);
    639 
    640 	return 0;
    641 }
    642 
    643 /**
    644  * Traverse the delayed list, and call ttm_bo_cleanup_refs on all
    645  * encountered buffers.
    646  */
    647 
    648 static int ttm_bo_delayed_delete(struct ttm_bo_device *bdev, bool remove_all)
    649 {
    650 	struct ttm_bo_global *glob = bdev->glob;
    651 	struct ttm_buffer_object *entry = NULL;
    652 	int ret = 0;
    653 
    654 	spin_lock(&glob->lru_lock);
    655 	if (list_empty(&bdev->ddestroy))
    656 		goto out_unlock;
    657 
    658 	entry = list_first_entry(&bdev->ddestroy,
    659 		struct ttm_buffer_object, ddestroy);
    660 	kref_get(&entry->list_kref);
    661 
    662 	for (;;) {
    663 		struct ttm_buffer_object *nentry = NULL;
    664 
    665 		if (entry->ddestroy.next != &bdev->ddestroy) {
    666 			nentry = list_first_entry(&entry->ddestroy,
    667 				struct ttm_buffer_object, ddestroy);
    668 			kref_get(&nentry->list_kref);
    669 		}
    670 
    671 		ret = ttm_bo_reserve_locked(entry, false, !remove_all, false, 0);
    672 		if (!ret)
    673 			ret = ttm_bo_cleanup_refs_and_unlock(entry, false,
    674 							     !remove_all);
    675 		else
    676 			spin_unlock(&glob->lru_lock);
    677 
    678 		kref_put(&entry->list_kref, ttm_bo_release_list);
    679 		entry = nentry;
    680 
    681 		if (ret || !entry)
    682 			goto out;
    683 
    684 		spin_lock(&glob->lru_lock);
    685 		if (list_empty(&entry->ddestroy))
    686 			break;
    687 	}
    688 
    689 out_unlock:
    690 	spin_unlock(&glob->lru_lock);
    691 out:
    692 	if (entry)
    693 		kref_put(&entry->list_kref, ttm_bo_release_list);
    694 	return ret;
    695 }
    696 
    697 static void ttm_bo_delayed_workqueue(struct work_struct *work)
    698 {
    699 	struct ttm_bo_device *bdev =
    700 	    container_of(work, struct ttm_bo_device, wq.work);
    701 
    702 	if (ttm_bo_delayed_delete(bdev, false)) {
    703 		schedule_delayed_work(&bdev->wq,
    704 				      ((HZ / 100) < 1) ? 1 : HZ / 100);
    705 	}
    706 }
    707 
    708 static void ttm_bo_release(struct kref *kref)
    709 {
    710 	struct ttm_buffer_object *bo =
    711 	    container_of(kref, struct ttm_buffer_object, kref);
    712 	struct ttm_bo_device *bdev = bo->bdev;
    713 	struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
    714 
    715 	write_lock(&bdev->vm_lock);
    716 	if (likely(bo->vm_node != NULL)) {
    717 		rb_erase(&bo->vm_rb, &bdev->addr_space_rb);
    718 		drm_mm_put_block(bo->vm_node);
    719 		bo->vm_node = NULL;
    720 	}
    721 	write_unlock(&bdev->vm_lock);
    722 	ttm_mem_io_lock(man, false);
    723 	ttm_mem_io_free_vm(bo);
    724 	ttm_mem_io_unlock(man);
    725 	ttm_bo_cleanup_refs_or_queue(bo);
    726 	kref_put(&bo->list_kref, ttm_bo_release_list);
    727 }
    728 
    729 void ttm_bo_unref(struct ttm_buffer_object **p_bo)
    730 {
    731 	struct ttm_buffer_object *bo = *p_bo;
    732 
    733 	*p_bo = NULL;
    734 	kref_put(&bo->kref, ttm_bo_release);
    735 }
    736 EXPORT_SYMBOL(ttm_bo_unref);
    737 
    738 int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev)
    739 {
    740 	return cancel_delayed_work_sync(&bdev->wq);
    741 }
    742 EXPORT_SYMBOL(ttm_bo_lock_delayed_workqueue);
    743 
    744 void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched)
    745 {
    746 	if (resched)
    747 		schedule_delayed_work(&bdev->wq,
    748 				      ((HZ / 100) < 1) ? 1 : HZ / 100);
    749 }
    750 EXPORT_SYMBOL(ttm_bo_unlock_delayed_workqueue);
    751 
    752 static int ttm_bo_evict(struct ttm_buffer_object *bo, bool interruptible,
    753 			bool no_wait_gpu)
    754 {
    755 	struct ttm_bo_device *bdev = bo->bdev;
    756 	struct ttm_mem_reg evict_mem;
    757 	struct ttm_placement placement;
    758 	int ret = 0;
    759 
    760 	spin_lock(&bdev->fence_lock);
    761 	ret = ttm_bo_wait(bo, false, interruptible, no_wait_gpu);
    762 	spin_unlock(&bdev->fence_lock);
    763 
    764 	if (unlikely(ret != 0)) {
    765 		if (ret != -ERESTARTSYS) {
    766 			pr_err("Failed to expire sync object before buffer eviction\n");
    767 		}
    768 		goto out;
    769 	}
    770 
    771 	BUG_ON(!ttm_bo_is_reserved(bo));
    772 
    773 	evict_mem = bo->mem;
    774 	evict_mem.mm_node = NULL;
    775 	evict_mem.bus.io_reserved_vm = false;
    776 	evict_mem.bus.io_reserved_count = 0;
    777 
    778 	placement.fpfn = 0;
    779 	placement.lpfn = 0;
    780 	placement.num_placement = 0;
    781 	placement.num_busy_placement = 0;
    782 	bdev->driver->evict_flags(bo, &placement);
    783 	ret = ttm_bo_mem_space(bo, &placement, &evict_mem, interruptible,
    784 				no_wait_gpu);
    785 	if (ret) {
    786 		if (ret != -ERESTARTSYS) {
    787 			pr_err("Failed to find memory space for buffer 0x%p eviction\n",
    788 			       bo);
    789 			ttm_bo_mem_space_debug(bo, &placement);
    790 		}
    791 		goto out;
    792 	}
    793 
    794 	ret = ttm_bo_handle_move_mem(bo, &evict_mem, true, interruptible,
    795 				     no_wait_gpu);
    796 	if (ret) {
    797 		if (ret != -ERESTARTSYS)
    798 			pr_err("Buffer eviction failed\n");
    799 		ttm_bo_mem_put(bo, &evict_mem);
    800 		goto out;
    801 	}
    802 	bo->evicted = true;
    803 out:
    804 	return ret;
    805 }
    806 
    807 static int ttm_mem_evict_first(struct ttm_bo_device *bdev,
    808 				uint32_t mem_type,
    809 				bool interruptible,
    810 				bool no_wait_gpu)
    811 {
    812 	struct ttm_bo_global *glob = bdev->glob;
    813 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
    814 	struct ttm_buffer_object *bo;
    815 	int ret = -EBUSY, put_count;
    816 
    817 	spin_lock(&glob->lru_lock);
    818 	list_for_each_entry(bo, &man->lru, lru) {
    819 		ret = ttm_bo_reserve_locked(bo, false, true, false, 0);
    820 		if (!ret)
    821 			break;
    822 	}
    823 
    824 	if (ret) {
    825 		spin_unlock(&glob->lru_lock);
    826 		return ret;
    827 	}
    828 
    829 	kref_get(&bo->list_kref);
    830 
    831 	if (!list_empty(&bo->ddestroy)) {
    832 		ret = ttm_bo_cleanup_refs_and_unlock(bo, interruptible,
    833 						     no_wait_gpu);
    834 		kref_put(&bo->list_kref, ttm_bo_release_list);
    835 		return ret;
    836 	}
    837 
    838 	put_count = ttm_bo_del_from_lru(bo);
    839 	spin_unlock(&glob->lru_lock);
    840 
    841 	BUG_ON(ret != 0);
    842 
    843 	ttm_bo_list_ref_sub(bo, put_count, true);
    844 
    845 	ret = ttm_bo_evict(bo, interruptible, no_wait_gpu);
    846 	ttm_bo_unreserve(bo);
    847 
    848 	kref_put(&bo->list_kref, ttm_bo_release_list);
    849 	return ret;
    850 }
    851 
    852 void ttm_bo_mem_put(struct ttm_buffer_object *bo, struct ttm_mem_reg *mem)
    853 {
    854 	struct ttm_mem_type_manager *man = &bo->bdev->man[mem->mem_type];
    855 
    856 	if (mem->mm_node)
    857 		(*man->func->put_node)(man, mem);
    858 }
    859 EXPORT_SYMBOL(ttm_bo_mem_put);
    860 
    861 /**
    862  * Repeatedly evict memory from the LRU for @mem_type until we create enough
    863  * space, or we've evicted everything and there isn't enough space.
    864  */
    865 static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
    866 					uint32_t mem_type,
    867 					struct ttm_placement *placement,
    868 					struct ttm_mem_reg *mem,
    869 					bool interruptible,
    870 					bool no_wait_gpu)
    871 {
    872 	struct ttm_bo_device *bdev = bo->bdev;
    873 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
    874 	int ret;
    875 
    876 	do {
    877 		ret = (*man->func->get_node)(man, bo, placement, mem);
    878 		if (unlikely(ret != 0))
    879 			return ret;
    880 		if (mem->mm_node)
    881 			break;
    882 		ret = ttm_mem_evict_first(bdev, mem_type,
    883 					  interruptible, no_wait_gpu);
    884 		if (unlikely(ret != 0))
    885 			return ret;
    886 	} while (1);
    887 	if (mem->mm_node == NULL)
    888 		return -ENOMEM;
    889 	mem->mem_type = mem_type;
    890 	return 0;
    891 }
    892 
    893 static uint32_t ttm_bo_select_caching(struct ttm_mem_type_manager *man,
    894 				      uint32_t cur_placement,
    895 				      uint32_t proposed_placement)
    896 {
    897 	uint32_t caching = proposed_placement & TTM_PL_MASK_CACHING;
    898 	uint32_t result = proposed_placement & ~TTM_PL_MASK_CACHING;
    899 
    900 	/**
    901 	 * Keep current caching if possible.
    902 	 */
    903 
    904 	if ((cur_placement & caching) != 0)
    905 		result |= (cur_placement & caching);
    906 	else if ((man->default_caching & caching) != 0)
    907 		result |= man->default_caching;
    908 	else if ((TTM_PL_FLAG_CACHED & caching) != 0)
    909 		result |= TTM_PL_FLAG_CACHED;
    910 	else if ((TTM_PL_FLAG_WC & caching) != 0)
    911 		result |= TTM_PL_FLAG_WC;
    912 	else if ((TTM_PL_FLAG_UNCACHED & caching) != 0)
    913 		result |= TTM_PL_FLAG_UNCACHED;
    914 
    915 	return result;
    916 }
    917 
    918 static bool ttm_bo_mt_compatible(struct ttm_mem_type_manager *man,
    919 				 uint32_t mem_type,
    920 				 uint32_t proposed_placement,
    921 				 uint32_t *masked_placement)
    922 {
    923 	uint32_t cur_flags = ttm_bo_type_flags(mem_type);
    924 
    925 	if ((cur_flags & proposed_placement & TTM_PL_MASK_MEM) == 0)
    926 		return false;
    927 
    928 	if ((proposed_placement & man->available_caching) == 0)
    929 		return false;
    930 
    931 	cur_flags |= (proposed_placement & man->available_caching);
    932 
    933 	*masked_placement = cur_flags;
    934 	return true;
    935 }
    936 
    937 /**
    938  * Creates space for memory region @mem according to its type.
    939  *
    940  * This function first searches for free space in compatible memory types in
    941  * the priority order defined by the driver.  If free space isn't found, then
    942  * ttm_bo_mem_force_space is attempted in priority order to evict and find
    943  * space.
    944  */
    945 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
    946 			struct ttm_placement *placement,
    947 			struct ttm_mem_reg *mem,
    948 			bool interruptible,
    949 			bool no_wait_gpu)
    950 {
    951 	struct ttm_bo_device *bdev = bo->bdev;
    952 	struct ttm_mem_type_manager *man;
    953 	uint32_t mem_type = TTM_PL_SYSTEM;
    954 	uint32_t cur_flags = 0;
    955 	bool type_found = false;
    956 	bool type_ok = false;
    957 	bool has_erestartsys = false;
    958 	int i, ret;
    959 
    960 	mem->mm_node = NULL;
    961 	for (i = 0; i < placement->num_placement; ++i) {
    962 		ret = ttm_mem_type_from_flags(placement->placement[i],
    963 						&mem_type);
    964 		if (ret)
    965 			return ret;
    966 		man = &bdev->man[mem_type];
    967 
    968 		type_ok = ttm_bo_mt_compatible(man,
    969 						mem_type,
    970 						placement->placement[i],
    971 						&cur_flags);
    972 
    973 		if (!type_ok)
    974 			continue;
    975 
    976 		cur_flags = ttm_bo_select_caching(man, bo->mem.placement,
    977 						  cur_flags);
    978 		/*
    979 		 * Use the access and other non-mapping-related flag bits from
    980 		 * the memory placement flags to the current flags
    981 		 */
    982 		ttm_flag_masked(&cur_flags, placement->placement[i],
    983 				~TTM_PL_MASK_MEMTYPE);
    984 
    985 		if (mem_type == TTM_PL_SYSTEM)
    986 			break;
    987 
    988 		if (man->has_type && man->use_type) {
    989 			type_found = true;
    990 			ret = (*man->func->get_node)(man, bo, placement, mem);
    991 			if (unlikely(ret))
    992 				return ret;
    993 		}
    994 		if (mem->mm_node)
    995 			break;
    996 	}
    997 
    998 	if ((type_ok && (mem_type == TTM_PL_SYSTEM)) || mem->mm_node) {
    999 		mem->mem_type = mem_type;
   1000 		mem->placement = cur_flags;
   1001 		return 0;
   1002 	}
   1003 
   1004 	if (!type_found)
   1005 		return -EINVAL;
   1006 
   1007 	for (i = 0; i < placement->num_busy_placement; ++i) {
   1008 		ret = ttm_mem_type_from_flags(placement->busy_placement[i],
   1009 						&mem_type);
   1010 		if (ret)
   1011 			return ret;
   1012 		man = &bdev->man[mem_type];
   1013 		if (!man->has_type)
   1014 			continue;
   1015 		if (!ttm_bo_mt_compatible(man,
   1016 						mem_type,
   1017 						placement->busy_placement[i],
   1018 						&cur_flags))
   1019 			continue;
   1020 
   1021 		cur_flags = ttm_bo_select_caching(man, bo->mem.placement,
   1022 						  cur_flags);
   1023 		/*
   1024 		 * Use the access and other non-mapping-related flag bits from
   1025 		 * the memory placement flags to the current flags
   1026 		 */
   1027 		ttm_flag_masked(&cur_flags, placement->busy_placement[i],
   1028 				~TTM_PL_MASK_MEMTYPE);
   1029 
   1030 
   1031 		if (mem_type == TTM_PL_SYSTEM) {
   1032 			mem->mem_type = mem_type;
   1033 			mem->placement = cur_flags;
   1034 			mem->mm_node = NULL;
   1035 			return 0;
   1036 		}
   1037 
   1038 		ret = ttm_bo_mem_force_space(bo, mem_type, placement, mem,
   1039 						interruptible, no_wait_gpu);
   1040 		if (ret == 0 && mem->mm_node) {
   1041 			mem->placement = cur_flags;
   1042 			return 0;
   1043 		}
   1044 		if (ret == -ERESTARTSYS)
   1045 			has_erestartsys = true;
   1046 	}
   1047 	ret = (has_erestartsys) ? -ERESTARTSYS : -ENOMEM;
   1048 	return ret;
   1049 }
   1050 EXPORT_SYMBOL(ttm_bo_mem_space);
   1051 
   1052 int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
   1053 			struct ttm_placement *placement,
   1054 			bool interruptible,
   1055 			bool no_wait_gpu)
   1056 {
   1057 	int ret = 0;
   1058 	struct ttm_mem_reg mem;
   1059 	struct ttm_bo_device *bdev = bo->bdev;
   1060 
   1061 	BUG_ON(!ttm_bo_is_reserved(bo));
   1062 
   1063 	/*
   1064 	 * FIXME: It's possible to pipeline buffer moves.
   1065 	 * Have the driver move function wait for idle when necessary,
   1066 	 * instead of doing it here.
   1067 	 */
   1068 	spin_lock(&bdev->fence_lock);
   1069 	ret = ttm_bo_wait(bo, false, interruptible, no_wait_gpu);
   1070 	spin_unlock(&bdev->fence_lock);
   1071 	if (ret)
   1072 		return ret;
   1073 	mem.num_pages = bo->num_pages;
   1074 	mem.size = mem.num_pages << PAGE_SHIFT;
   1075 	mem.page_alignment = bo->mem.page_alignment;
   1076 	mem.bus.io_reserved_vm = false;
   1077 	mem.bus.io_reserved_count = 0;
   1078 	/*
   1079 	 * Determine where to move the buffer.
   1080 	 */
   1081 	ret = ttm_bo_mem_space(bo, placement, &mem,
   1082 			       interruptible, no_wait_gpu);
   1083 	if (ret)
   1084 		goto out_unlock;
   1085 	ret = ttm_bo_handle_move_mem(bo, &mem, false,
   1086 				     interruptible, no_wait_gpu);
   1087 out_unlock:
   1088 	if (ret && mem.mm_node)
   1089 		ttm_bo_mem_put(bo, &mem);
   1090 	return ret;
   1091 }
   1092 
   1093 static int ttm_bo_mem_compat(struct ttm_placement *placement,
   1094 			     struct ttm_mem_reg *mem)
   1095 {
   1096 	int i;
   1097 
   1098 	if (mem->mm_node && placement->lpfn != 0 &&
   1099 	    (mem->start < placement->fpfn ||
   1100 	     mem->start + mem->num_pages > placement->lpfn))
   1101 		return -1;
   1102 
   1103 	for (i = 0; i < placement->num_placement; i++) {
   1104 		if ((placement->placement[i] & mem->placement &
   1105 			TTM_PL_MASK_CACHING) &&
   1106 			(placement->placement[i] & mem->placement &
   1107 			TTM_PL_MASK_MEM))
   1108 			return i;
   1109 	}
   1110 	return -1;
   1111 }
   1112 
   1113 int ttm_bo_validate(struct ttm_buffer_object *bo,
   1114 			struct ttm_placement *placement,
   1115 			bool interruptible,
   1116 			bool no_wait_gpu)
   1117 {
   1118 	int ret;
   1119 
   1120 	BUG_ON(!ttm_bo_is_reserved(bo));
   1121 	/* Check that range is valid */
   1122 	if (placement->lpfn || placement->fpfn)
   1123 		if (placement->fpfn > placement->lpfn ||
   1124 			(placement->lpfn - placement->fpfn) < bo->num_pages)
   1125 			return -EINVAL;
   1126 	/*
   1127 	 * Check whether we need to move buffer.
   1128 	 */
   1129 	ret = ttm_bo_mem_compat(placement, &bo->mem);
   1130 	if (ret < 0) {
   1131 		ret = ttm_bo_move_buffer(bo, placement, interruptible,
   1132 					 no_wait_gpu);
   1133 		if (ret)
   1134 			return ret;
   1135 	} else {
   1136 		/*
   1137 		 * Use the access and other non-mapping-related flag bits from
   1138 		 * the compatible memory placement flags to the active flags
   1139 		 */
   1140 		ttm_flag_masked(&bo->mem.placement, placement->placement[ret],
   1141 				~TTM_PL_MASK_MEMTYPE);
   1142 	}
   1143 	/*
   1144 	 * We might need to add a TTM.
   1145 	 */
   1146 	if (bo->mem.mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {
   1147 		ret = ttm_bo_add_ttm(bo, true);
   1148 		if (ret)
   1149 			return ret;
   1150 	}
   1151 	return 0;
   1152 }
   1153 EXPORT_SYMBOL(ttm_bo_validate);
   1154 
   1155 int ttm_bo_check_placement(struct ttm_buffer_object *bo,
   1156 				struct ttm_placement *placement)
   1157 {
   1158 	BUG_ON((placement->fpfn || placement->lpfn) &&
   1159 	       (bo->mem.num_pages > (placement->lpfn - placement->fpfn)));
   1160 
   1161 	return 0;
   1162 }
   1163 
   1164 int ttm_bo_init(struct ttm_bo_device *bdev,
   1165 		struct ttm_buffer_object *bo,
   1166 		unsigned long size,
   1167 		enum ttm_bo_type type,
   1168 		struct ttm_placement *placement,
   1169 		uint32_t page_alignment,
   1170 		bool interruptible,
   1171 		struct file *persistent_swap_storage,
   1172 		size_t acc_size,
   1173 		struct sg_table *sg,
   1174 		void (*destroy) (struct ttm_buffer_object *))
   1175 {
   1176 	int ret = 0;
   1177 	unsigned long num_pages;
   1178 	struct ttm_mem_global *mem_glob = bdev->glob->mem_glob;
   1179 
   1180 	ret = ttm_mem_global_alloc(mem_glob, acc_size, false, false);
   1181 	if (ret) {
   1182 		pr_err("Out of kernel memory\n");
   1183 		if (destroy)
   1184 			(*destroy)(bo);
   1185 		else
   1186 			kfree(bo);
   1187 		return -ENOMEM;
   1188 	}
   1189 
   1190 	num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
   1191 	if (num_pages == 0) {
   1192 		pr_err("Illegal buffer object size\n");
   1193 		if (destroy)
   1194 			(*destroy)(bo);
   1195 		else
   1196 			kfree(bo);
   1197 		ttm_mem_global_free(mem_glob, acc_size);
   1198 		return -EINVAL;
   1199 	}
   1200 	bo->destroy = destroy;
   1201 
   1202 	kref_init(&bo->kref);
   1203 	kref_init(&bo->list_kref);
   1204 	atomic_set(&bo->cpu_writers, 0);
   1205 	atomic_set(&bo->reserved, 1);
   1206 	init_waitqueue_head(&bo->event_queue);
   1207 	INIT_LIST_HEAD(&bo->lru);
   1208 	INIT_LIST_HEAD(&bo->ddestroy);
   1209 	INIT_LIST_HEAD(&bo->swap);
   1210 	INIT_LIST_HEAD(&bo->io_reserve_lru);
   1211 	bo->bdev = bdev;
   1212 	bo->glob = bdev->glob;
   1213 	bo->type = type;
   1214 	bo->num_pages = num_pages;
   1215 	bo->mem.size = num_pages << PAGE_SHIFT;
   1216 	bo->mem.mem_type = TTM_PL_SYSTEM;
   1217 	bo->mem.num_pages = bo->num_pages;
   1218 	bo->mem.mm_node = NULL;
   1219 	bo->mem.page_alignment = page_alignment;
   1220 	bo->mem.bus.io_reserved_vm = false;
   1221 	bo->mem.bus.io_reserved_count = 0;
   1222 	bo->priv_flags = 0;
   1223 	bo->mem.placement = (TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED);
   1224 	bo->seq_valid = false;
   1225 	bo->persistent_swap_storage = persistent_swap_storage;
   1226 	bo->acc_size = acc_size;
   1227 	bo->sg = sg;
   1228 	atomic_inc(&bo->glob->bo_count);
   1229 
   1230 	ret = ttm_bo_check_placement(bo, placement);
   1231 	if (unlikely(ret != 0))
   1232 		goto out_err;
   1233 
   1234 	/*
   1235 	 * For ttm_bo_type_device buffers, allocate
   1236 	 * address space from the device.
   1237 	 */
   1238 	if (bo->type == ttm_bo_type_device ||
   1239 	    bo->type == ttm_bo_type_sg) {
   1240 		ret = ttm_bo_setup_vm(bo);
   1241 		if (ret)
   1242 			goto out_err;
   1243 	}
   1244 
   1245 	ret = ttm_bo_validate(bo, placement, interruptible, false);
   1246 	if (ret)
   1247 		goto out_err;
   1248 
   1249 	ttm_bo_unreserve(bo);
   1250 	return 0;
   1251 
   1252 out_err:
   1253 	ttm_bo_unreserve(bo);
   1254 	ttm_bo_unref(&bo);
   1255 
   1256 	return ret;
   1257 }
   1258 EXPORT_SYMBOL(ttm_bo_init);
   1259 
   1260 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
   1261 		       unsigned long bo_size,
   1262 		       unsigned struct_size)
   1263 {
   1264 	unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
   1265 	size_t size = 0;
   1266 
   1267 	size += ttm_round_pot(struct_size);
   1268 	size += PAGE_ALIGN(npages * sizeof(void *));
   1269 	size += ttm_round_pot(sizeof(struct ttm_tt));
   1270 	return size;
   1271 }
   1272 EXPORT_SYMBOL(ttm_bo_acc_size);
   1273 
   1274 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
   1275 			   unsigned long bo_size,
   1276 			   unsigned struct_size)
   1277 {
   1278 	unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
   1279 	size_t size = 0;
   1280 
   1281 	size += ttm_round_pot(struct_size);
   1282 	size += PAGE_ALIGN(npages * sizeof(void *));
   1283 	size += PAGE_ALIGN(npages * sizeof(dma_addr_t));
   1284 	size += ttm_round_pot(sizeof(struct ttm_dma_tt));
   1285 	return size;
   1286 }
   1287 EXPORT_SYMBOL(ttm_bo_dma_acc_size);
   1288 
   1289 int ttm_bo_create(struct ttm_bo_device *bdev,
   1290 			unsigned long size,
   1291 			enum ttm_bo_type type,
   1292 			struct ttm_placement *placement,
   1293 			uint32_t page_alignment,
   1294 			bool interruptible,
   1295 			struct file *persistent_swap_storage,
   1296 			struct ttm_buffer_object **p_bo)
   1297 {
   1298 	struct ttm_buffer_object *bo;
   1299 	size_t acc_size;
   1300 	int ret;
   1301 
   1302 	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
   1303 	if (unlikely(bo == NULL))
   1304 		return -ENOMEM;
   1305 
   1306 	acc_size = ttm_bo_acc_size(bdev, size, sizeof(struct ttm_buffer_object));
   1307 	ret = ttm_bo_init(bdev, bo, size, type, placement, page_alignment,
   1308 			  interruptible, persistent_swap_storage, acc_size,
   1309 			  NULL, NULL);
   1310 	if (likely(ret == 0))
   1311 		*p_bo = bo;
   1312 
   1313 	return ret;
   1314 }
   1315 EXPORT_SYMBOL(ttm_bo_create);
   1316 
   1317 static int ttm_bo_force_list_clean(struct ttm_bo_device *bdev,
   1318 					unsigned mem_type, bool allow_errors)
   1319 {
   1320 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
   1321 	struct ttm_bo_global *glob = bdev->glob;
   1322 	int ret;
   1323 
   1324 	/*
   1325 	 * Can't use standard list traversal since we're unlocking.
   1326 	 */
   1327 
   1328 	spin_lock(&glob->lru_lock);
   1329 	while (!list_empty(&man->lru)) {
   1330 		spin_unlock(&glob->lru_lock);
   1331 		ret = ttm_mem_evict_first(bdev, mem_type, false, false);
   1332 		if (ret) {
   1333 			if (allow_errors) {
   1334 				return ret;
   1335 			} else {
   1336 				pr_err("Cleanup eviction failed\n");
   1337 			}
   1338 		}
   1339 		spin_lock(&glob->lru_lock);
   1340 	}
   1341 	spin_unlock(&glob->lru_lock);
   1342 	return 0;
   1343 }
   1344 
   1345 int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type)
   1346 {
   1347 	struct ttm_mem_type_manager *man;
   1348 	int ret = -EINVAL;
   1349 
   1350 	if (mem_type >= TTM_NUM_MEM_TYPES) {
   1351 		pr_err("Illegal memory type %d\n", mem_type);
   1352 		return ret;
   1353 	}
   1354 	man = &bdev->man[mem_type];
   1355 
   1356 	if (!man->has_type) {
   1357 		pr_err("Trying to take down uninitialized memory manager type %u\n",
   1358 		       mem_type);
   1359 		return ret;
   1360 	}
   1361 
   1362 	man->use_type = false;
   1363 	man->has_type = false;
   1364 
   1365 	ret = 0;
   1366 	if (mem_type > 0) {
   1367 		ttm_bo_force_list_clean(bdev, mem_type, false);
   1368 
   1369 		ret = (*man->func->takedown)(man);
   1370 	}
   1371 
   1372 	return ret;
   1373 }
   1374 EXPORT_SYMBOL(ttm_bo_clean_mm);
   1375 
   1376 int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type)
   1377 {
   1378 	struct ttm_mem_type_manager *man = &bdev->man[mem_type];
   1379 
   1380 	if (mem_type == 0 || mem_type >= TTM_NUM_MEM_TYPES) {
   1381 		pr_err("Illegal memory manager memory type %u\n", mem_type);
   1382 		return -EINVAL;
   1383 	}
   1384 
   1385 	if (!man->has_type) {
   1386 		pr_err("Memory type %u has not been initialized\n", mem_type);
   1387 		return 0;
   1388 	}
   1389 
   1390 	return ttm_bo_force_list_clean(bdev, mem_type, true);
   1391 }
   1392 EXPORT_SYMBOL(ttm_bo_evict_mm);
   1393 
   1394 int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
   1395 			unsigned long p_size)
   1396 {
   1397 	int ret = -EINVAL;
   1398 	struct ttm_mem_type_manager *man;
   1399 
   1400 	BUG_ON(type >= TTM_NUM_MEM_TYPES);
   1401 	man = &bdev->man[type];
   1402 	BUG_ON(man->has_type);
   1403 	man->io_reserve_fastpath = true;
   1404 	man->use_io_reserve_lru = false;
   1405 	mutex_init(&man->io_reserve_mutex);
   1406 	INIT_LIST_HEAD(&man->io_reserve_lru);
   1407 
   1408 	ret = bdev->driver->init_mem_type(bdev, type, man);
   1409 	if (ret)
   1410 		return ret;
   1411 	man->bdev = bdev;
   1412 
   1413 	ret = 0;
   1414 	if (type != TTM_PL_SYSTEM) {
   1415 		ret = (*man->func->init)(man, p_size);
   1416 		if (ret)
   1417 			return ret;
   1418 	}
   1419 	man->has_type = true;
   1420 	man->use_type = true;
   1421 	man->size = p_size;
   1422 
   1423 	INIT_LIST_HEAD(&man->lru);
   1424 
   1425 	return 0;
   1426 }
   1427 EXPORT_SYMBOL(ttm_bo_init_mm);
   1428 
   1429 static void ttm_bo_global_kobj_release(struct kobject *kobj)
   1430 {
   1431 	struct ttm_bo_global *glob =
   1432 		container_of(kobj, struct ttm_bo_global, kobj);
   1433 
   1434 	ttm_mem_unregister_shrink(glob->mem_glob, &glob->shrink);
   1435 	__free_page(glob->dummy_read_page);
   1436 	kfree(glob);
   1437 }
   1438 
   1439 void ttm_bo_global_release(struct drm_global_reference *ref)
   1440 {
   1441 	struct ttm_bo_global *glob = ref->object;
   1442 
   1443 	kobject_del(&glob->kobj);
   1444 	kobject_put(&glob->kobj);
   1445 }
   1446 EXPORT_SYMBOL(ttm_bo_global_release);
   1447 
   1448 int ttm_bo_global_init(struct drm_global_reference *ref)
   1449 {
   1450 	struct ttm_bo_global_ref *bo_ref =
   1451 		container_of(ref, struct ttm_bo_global_ref, ref);
   1452 	struct ttm_bo_global *glob = ref->object;
   1453 	int ret;
   1454 
   1455 	mutex_init(&glob->device_list_mutex);
   1456 	spin_lock_init(&glob->lru_lock);
   1457 	glob->mem_glob = bo_ref->mem_glob;
   1458 	glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32);
   1459 
   1460 	if (unlikely(glob->dummy_read_page == NULL)) {
   1461 		ret = -ENOMEM;
   1462 		goto out_no_drp;
   1463 	}
   1464 
   1465 	INIT_LIST_HEAD(&glob->swap_lru);
   1466 	INIT_LIST_HEAD(&glob->device_list);
   1467 
   1468 	ttm_mem_init_shrink(&glob->shrink, ttm_bo_swapout);
   1469 	ret = ttm_mem_register_shrink(glob->mem_glob, &glob->shrink);
   1470 	if (unlikely(ret != 0)) {
   1471 		pr_err("Could not register buffer object swapout\n");
   1472 		goto out_no_shrink;
   1473 	}
   1474 
   1475 	atomic_set(&glob->bo_count, 0);
   1476 
   1477 	ret = kobject_init_and_add(
   1478 		&glob->kobj, &ttm_bo_glob_kobj_type, ttm_get_kobj(), "buffer_objects");
   1479 	if (unlikely(ret != 0))
   1480 		kobject_put(&glob->kobj);
   1481 	return ret;
   1482 out_no_shrink:
   1483 	__free_page(glob->dummy_read_page);
   1484 out_no_drp:
   1485 	kfree(glob);
   1486 	return ret;
   1487 }
   1488 EXPORT_SYMBOL(ttm_bo_global_init);
   1489 
   1490 
   1491 int ttm_bo_device_release(struct ttm_bo_device *bdev)
   1492 {
   1493 	int ret = 0;
   1494 	unsigned i = TTM_NUM_MEM_TYPES;
   1495 	struct ttm_mem_type_manager *man;
   1496 	struct ttm_bo_global *glob = bdev->glob;
   1497 
   1498 	while (i--) {
   1499 		man = &bdev->man[i];
   1500 		if (man->has_type) {
   1501 			man->use_type = false;
   1502 			if ((i != TTM_PL_SYSTEM) && ttm_bo_clean_mm(bdev, i)) {
   1503 				ret = -EBUSY;
   1504 				pr_err("DRM memory manager type %d is not clean\n",
   1505 				       i);
   1506 			}
   1507 			man->has_type = false;
   1508 		}
   1509 	}
   1510 
   1511 	mutex_lock(&glob->device_list_mutex);
   1512 	list_del(&bdev->device_list);
   1513 	mutex_unlock(&glob->device_list_mutex);
   1514 
   1515 	cancel_delayed_work_sync(&bdev->wq);
   1516 
   1517 	while (ttm_bo_delayed_delete(bdev, true))
   1518 		;
   1519 
   1520 	spin_lock(&glob->lru_lock);
   1521 	if (list_empty(&bdev->ddestroy))
   1522 		TTM_DEBUG("Delayed destroy list was clean\n");
   1523 
   1524 	if (list_empty(&bdev->man[0].lru))
   1525 		TTM_DEBUG("Swap list was clean\n");
   1526 	spin_unlock(&glob->lru_lock);
   1527 
   1528 	BUG_ON(!drm_mm_clean(&bdev->addr_space_mm));
   1529 	write_lock(&bdev->vm_lock);
   1530 	drm_mm_takedown(&bdev->addr_space_mm);
   1531 	write_unlock(&bdev->vm_lock);
   1532 
   1533 	return ret;
   1534 }
   1535 EXPORT_SYMBOL(ttm_bo_device_release);
   1536 
   1537 int ttm_bo_device_init(struct ttm_bo_device *bdev,
   1538 		       struct ttm_bo_global *glob,
   1539 		       struct ttm_bo_driver *driver,
   1540 		       uint64_t file_page_offset,
   1541 		       bool need_dma32)
   1542 {
   1543 	int ret = -EINVAL;
   1544 
   1545 	rwlock_init(&bdev->vm_lock);
   1546 	bdev->driver = driver;
   1547 
   1548 	memset(bdev->man, 0, sizeof(bdev->man));
   1549 
   1550 	/*
   1551 	 * Initialize the system memory buffer type.
   1552 	 * Other types need to be driver / IOCTL initialized.
   1553 	 */
   1554 	ret = ttm_bo_init_mm(bdev, TTM_PL_SYSTEM, 0);
   1555 	if (unlikely(ret != 0))
   1556 		goto out_no_sys;
   1557 
   1558 	bdev->addr_space_rb = RB_ROOT;
   1559 	ret = drm_mm_init(&bdev->addr_space_mm, file_page_offset, 0x10000000);
   1560 	if (unlikely(ret != 0))
   1561 		goto out_no_addr_mm;
   1562 
   1563 	INIT_DELAYED_WORK(&bdev->wq, ttm_bo_delayed_workqueue);
   1564 	INIT_LIST_HEAD(&bdev->ddestroy);
   1565 	bdev->dev_mapping = NULL;
   1566 	bdev->glob = glob;
   1567 	bdev->need_dma32 = need_dma32;
   1568 	bdev->val_seq = 0;
   1569 	spin_lock_init(&bdev->fence_lock);
   1570 	mutex_lock(&glob->device_list_mutex);
   1571 	list_add_tail(&bdev->device_list, &glob->device_list);
   1572 	mutex_unlock(&glob->device_list_mutex);
   1573 
   1574 	return 0;
   1575 out_no_addr_mm:
   1576 	ttm_bo_clean_mm(bdev, 0);
   1577 out_no_sys:
   1578 	return ret;
   1579 }
   1580 EXPORT_SYMBOL(ttm_bo_device_init);
   1581 
   1582 /*
   1583  * buffer object vm functions.
   1584  */
   1585 
   1586 bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem)
   1587 {
   1588 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
   1589 
   1590 	if (!(man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
   1591 		if (mem->mem_type == TTM_PL_SYSTEM)
   1592 			return false;
   1593 
   1594 		if (man->flags & TTM_MEMTYPE_FLAG_CMA)
   1595 			return false;
   1596 
   1597 		if (mem->placement & TTM_PL_FLAG_CACHED)
   1598 			return false;
   1599 	}
   1600 	return true;
   1601 }
   1602 
   1603 void ttm_bo_unmap_virtual_locked(struct ttm_buffer_object *bo)
   1604 {
   1605 	struct ttm_bo_device *bdev = bo->bdev;
   1606 	loff_t offset = (loff_t) bo->addr_space_offset;
   1607 	loff_t holelen = ((loff_t) bo->mem.num_pages) << PAGE_SHIFT;
   1608 
   1609 	if (!bdev->dev_mapping)
   1610 		return;
   1611 	unmap_mapping_range(bdev->dev_mapping, offset, holelen, 1);
   1612 	ttm_mem_io_free_vm(bo);
   1613 }
   1614 
   1615 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo)
   1616 {
   1617 	struct ttm_bo_device *bdev = bo->bdev;
   1618 	struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
   1619 
   1620 	ttm_mem_io_lock(man, false);
   1621 	ttm_bo_unmap_virtual_locked(bo);
   1622 	ttm_mem_io_unlock(man);
   1623 }
   1624 
   1625 
   1626 EXPORT_SYMBOL(ttm_bo_unmap_virtual);
   1627 
   1628 static void ttm_bo_vm_insert_rb(struct ttm_buffer_object *bo)
   1629 {
   1630 	struct ttm_bo_device *bdev = bo->bdev;
   1631 	struct rb_node **cur = &bdev->addr_space_rb.rb_node;
   1632 	struct rb_node *parent = NULL;
   1633 	struct ttm_buffer_object *cur_bo;
   1634 	unsigned long offset = bo->vm_node->start;
   1635 	unsigned long cur_offset;
   1636 
   1637 	while (*cur) {
   1638 		parent = *cur;
   1639 		cur_bo = rb_entry(parent, struct ttm_buffer_object, vm_rb);
   1640 		cur_offset = cur_bo->vm_node->start;
   1641 		if (offset < cur_offset)
   1642 			cur = &parent->rb_left;
   1643 		else if (offset > cur_offset)
   1644 			cur = &parent->rb_right;
   1645 		else
   1646 			BUG();
   1647 	}
   1648 
   1649 	rb_link_node(&bo->vm_rb, parent, cur);
   1650 	rb_insert_color(&bo->vm_rb, &bdev->addr_space_rb);
   1651 }
   1652 
   1653 /**
   1654  * ttm_bo_setup_vm:
   1655  *
   1656  * @bo: the buffer to allocate address space for
   1657  *
   1658  * Allocate address space in the drm device so that applications
   1659  * can mmap the buffer and access the contents. This only
   1660  * applies to ttm_bo_type_device objects as others are not
   1661  * placed in the drm device address space.
   1662  */
   1663 
   1664 static int ttm_bo_setup_vm(struct ttm_buffer_object *bo)
   1665 {
   1666 	struct ttm_bo_device *bdev = bo->bdev;
   1667 	int ret;
   1668 
   1669 retry_pre_get:
   1670 	ret = drm_mm_pre_get(&bdev->addr_space_mm);
   1671 	if (unlikely(ret != 0))
   1672 		return ret;
   1673 
   1674 	write_lock(&bdev->vm_lock);
   1675 	bo->vm_node = drm_mm_search_free(&bdev->addr_space_mm,
   1676 					 bo->mem.num_pages, 0, 0);
   1677 
   1678 	if (unlikely(bo->vm_node == NULL)) {
   1679 		ret = -ENOMEM;
   1680 		goto out_unlock;
   1681 	}
   1682 
   1683 	bo->vm_node = drm_mm_get_block_atomic(bo->vm_node,
   1684 					      bo->mem.num_pages, 0);
   1685 
   1686 	if (unlikely(bo->vm_node == NULL)) {
   1687 		write_unlock(&bdev->vm_lock);
   1688 		goto retry_pre_get;
   1689 	}
   1690 
   1691 	ttm_bo_vm_insert_rb(bo);
   1692 	write_unlock(&bdev->vm_lock);
   1693 	bo->addr_space_offset = ((uint64_t) bo->vm_node->start) << PAGE_SHIFT;
   1694 
   1695 	return 0;
   1696 out_unlock:
   1697 	write_unlock(&bdev->vm_lock);
   1698 	return ret;
   1699 }
   1700 
   1701 int ttm_bo_wait(struct ttm_buffer_object *bo,
   1702 		bool lazy, bool interruptible, bool no_wait)
   1703 {
   1704 	struct ttm_bo_driver *driver = bo->bdev->driver;
   1705 	struct ttm_bo_device *bdev = bo->bdev;
   1706 	void *sync_obj;
   1707 	int ret = 0;
   1708 
   1709 	if (likely(bo->sync_obj == NULL))
   1710 		return 0;
   1711 
   1712 	while (bo->sync_obj) {
   1713 
   1714 		if (driver->sync_obj_signaled(bo->sync_obj)) {
   1715 			void *tmp_obj = bo->sync_obj;
   1716 			bo->sync_obj = NULL;
   1717 			clear_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags);
   1718 			spin_unlock(&bdev->fence_lock);
   1719 			driver->sync_obj_unref(&tmp_obj);
   1720 			spin_lock(&bdev->fence_lock);
   1721 			continue;
   1722 		}
   1723 
   1724 		if (no_wait)
   1725 			return -EBUSY;
   1726 
   1727 		sync_obj = driver->sync_obj_ref(bo->sync_obj);
   1728 		spin_unlock(&bdev->fence_lock);
   1729 		ret = driver->sync_obj_wait(sync_obj,
   1730 					    lazy, interruptible);
   1731 		if (unlikely(ret != 0)) {
   1732 			driver->sync_obj_unref(&sync_obj);
   1733 			spin_lock(&bdev->fence_lock);
   1734 			return ret;
   1735 		}
   1736 		spin_lock(&bdev->fence_lock);
   1737 		if (likely(bo->sync_obj == sync_obj)) {
   1738 			void *tmp_obj = bo->sync_obj;
   1739 			bo->sync_obj = NULL;
   1740 			clear_bit(TTM_BO_PRIV_FLAG_MOVING,
   1741 				  &bo->priv_flags);
   1742 			spin_unlock(&bdev->fence_lock);
   1743 			driver->sync_obj_unref(&sync_obj);
   1744 			driver->sync_obj_unref(&tmp_obj);
   1745 			spin_lock(&bdev->fence_lock);
   1746 		} else {
   1747 			spin_unlock(&bdev->fence_lock);
   1748 			driver->sync_obj_unref(&sync_obj);
   1749 			spin_lock(&bdev->fence_lock);
   1750 		}
   1751 	}
   1752 	return 0;
   1753 }
   1754 EXPORT_SYMBOL(ttm_bo_wait);
   1755 
   1756 int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait)
   1757 {
   1758 	struct ttm_bo_device *bdev = bo->bdev;
   1759 	int ret = 0;
   1760 
   1761 	/*
   1762 	 * Using ttm_bo_reserve makes sure the lru lists are updated.
   1763 	 */
   1764 
   1765 	ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
   1766 	if (unlikely(ret != 0))
   1767 		return ret;
   1768 	spin_lock(&bdev->fence_lock);
   1769 	ret = ttm_bo_wait(bo, false, true, no_wait);
   1770 	spin_unlock(&bdev->fence_lock);
   1771 	if (likely(ret == 0))
   1772 		atomic_inc(&bo->cpu_writers);
   1773 	ttm_bo_unreserve(bo);
   1774 	return ret;
   1775 }
   1776 EXPORT_SYMBOL(ttm_bo_synccpu_write_grab);
   1777 
   1778 void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo)
   1779 {
   1780 	atomic_dec(&bo->cpu_writers);
   1781 }
   1782 EXPORT_SYMBOL(ttm_bo_synccpu_write_release);
   1783 
   1784 /**
   1785  * A buffer object shrink method that tries to swap out the first
   1786  * buffer object on the bo_global::swap_lru list.
   1787  */
   1788 
   1789 static int ttm_bo_swapout(struct ttm_mem_shrink *shrink)
   1790 {
   1791 	struct ttm_bo_global *glob =
   1792 	    container_of(shrink, struct ttm_bo_global, shrink);
   1793 	struct ttm_buffer_object *bo;
   1794 	int ret = -EBUSY;
   1795 	int put_count;
   1796 	uint32_t swap_placement = (TTM_PL_FLAG_CACHED | TTM_PL_FLAG_SYSTEM);
   1797 
   1798 	spin_lock(&glob->lru_lock);
   1799 	list_for_each_entry(bo, &glob->swap_lru, swap) {
   1800 		ret = ttm_bo_reserve_locked(bo, false, true, false, 0);
   1801 		if (!ret)
   1802 			break;
   1803 	}
   1804 
   1805 	if (ret) {
   1806 		spin_unlock(&glob->lru_lock);
   1807 		return ret;
   1808 	}
   1809 
   1810 	kref_get(&bo->list_kref);
   1811 
   1812 	if (!list_empty(&bo->ddestroy)) {
   1813 		ret = ttm_bo_cleanup_refs_and_unlock(bo, false, false);
   1814 		kref_put(&bo->list_kref, ttm_bo_release_list);
   1815 		return ret;
   1816 	}
   1817 
   1818 	put_count = ttm_bo_del_from_lru(bo);
   1819 	spin_unlock(&glob->lru_lock);
   1820 
   1821 	ttm_bo_list_ref_sub(bo, put_count, true);
   1822 
   1823 	/**
   1824 	 * Wait for GPU, then move to system cached.
   1825 	 */
   1826 
   1827 	spin_lock(&bo->bdev->fence_lock);
   1828 	ret = ttm_bo_wait(bo, false, false, false);
   1829 	spin_unlock(&bo->bdev->fence_lock);
   1830 
   1831 	if (unlikely(ret != 0))
   1832 		goto out;
   1833 
   1834 	if ((bo->mem.placement & swap_placement) != swap_placement) {
   1835 		struct ttm_mem_reg evict_mem;
   1836 
   1837 		evict_mem = bo->mem;
   1838 		evict_mem.mm_node = NULL;
   1839 		evict_mem.placement = TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED;
   1840 		evict_mem.mem_type = TTM_PL_SYSTEM;
   1841 
   1842 		ret = ttm_bo_handle_move_mem(bo, &evict_mem, true,
   1843 					     false, false);
   1844 		if (unlikely(ret != 0))
   1845 			goto out;
   1846 	}
   1847 
   1848 	ttm_bo_unmap_virtual(bo);
   1849 
   1850 	/**
   1851 	 * Swap out. Buffer will be swapped in again as soon as
   1852 	 * anyone tries to access a ttm page.
   1853 	 */
   1854 
   1855 	if (bo->bdev->driver->swap_notify)
   1856 		bo->bdev->driver->swap_notify(bo);
   1857 
   1858 	ret = ttm_tt_swapout(bo->ttm, bo->persistent_swap_storage);
   1859 out:
   1860 
   1861 	/**
   1862 	 *
   1863 	 * Unreserve without putting on LRU to avoid swapping out an
   1864 	 * already swapped buffer.
   1865 	 */
   1866 
   1867 	atomic_set(&bo->reserved, 0);
   1868 	wake_up_all(&bo->event_queue);
   1869 	kref_put(&bo->list_kref, ttm_bo_release_list);
   1870 	return ret;
   1871 }
   1872 
   1873 void ttm_bo_swapout_all(struct ttm_bo_device *bdev)
   1874 {
   1875 	while (ttm_bo_swapout(&bdev->glob->shrink) == 0)
   1876 		;
   1877 }
   1878 EXPORT_SYMBOL(ttm_bo_swapout_all);
   1879