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/**************************************************************************

 *

 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA

 * All Rights Reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the

 * "Software"), to deal in the Software without restriction, including

 * without limitation the rights to use, copy, modify, merge, publish,

 * distribute, sub license, and/or sell copies of the Software, and to

 * permit persons to whom the Software is furnished to do so, subject to

 * the following conditions:

 *

 * The above copyright notice and this permission notice (including the

 * next paragraph) shall be included in all copies or substantial portions

 * of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL

 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,

 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR

 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE

 * USE OR OTHER DEALINGS IN THE SOFTWARE.

 *

 **************************************************************************/

/*

 * Authors: Thomas Hellstrom 

 */

#define pr_fmt(fmt) "[TTM] " fmt

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#define TTM_ASSERT_LOCKED(param)

#define TTM_DEBUG(fmt, arg...)

#define TTM_BO_HASH_ORDER 13

static inline int ttm_mem_type_from_place(const struct ttm_place *place,

					  uint32_t *mem_type)

{

	int i;

	for (i = 0; i <= TTM_PL_PRIV5; i++)

		if (place->flags & (1 << i)) {

			*mem_type = i;

			return 0;

		}

	return -EINVAL;

}

static inline uint32_t ttm_bo_type_flags(unsigned type)

{

	return 1 << (type);

}

static void ttm_bo_release_list(struct kref *list_kref)

{

	struct ttm_buffer_object *bo =

	    container_of(list_kref, struct ttm_buffer_object, list_kref);

	struct ttm_bo_device *bdev = bo->bdev;

	size_t acc_size = bo->acc_size;

	BUG_ON(atomic_read(&bo->list_kref.refcount));

	BUG_ON(atomic_read(&bo->kref.refcount));

	BUG_ON(atomic_read(&bo->cpu_writers));

	BUG_ON(bo->mem.mm_node != NULL);

	BUG_ON(!list_empty(&bo->lru));

	BUG_ON(!list_empty(&bo->ddestroy));

	if (bo->ttm)

		ttm_tt_destroy(bo->ttm);

	atomic_dec(&bo->glob->bo_count);

	if (bo->resv == &bo->ttm_resv)

		reservation_object_fini(&bo->ttm_resv);

	mutex_destroy(&bo->wu_mutex);

	if (bo->destroy)

		bo->destroy(bo);

	else {

		kfree(bo);

	}

}

void ttm_bo_add_to_lru(struct ttm_buffer_object *bo)

{

	struct ttm_bo_device *bdev = bo->bdev;

	struct ttm_mem_type_manager *man;

	lockdep_assert_held(&bo->resv->lock.base);

	if (!(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {

		BUG_ON(!list_empty(&bo->lru));

		man = &bdev->man[bo->mem.mem_type];

		list_add_tail(&bo->lru, &man->lru);

		kref_get(&bo->list_kref);

		if (bo->ttm != NULL) {

			list_add_tail(&bo->swap, &bo->glob->swap_lru);

			kref_get(&bo->list_kref);

		}

	}

}

EXPORT_SYMBOL(ttm_bo_add_to_lru);

int ttm_bo_del_from_lru(struct ttm_buffer_object *bo)

{

	int put_count = 0;

	if (!list_empty(&bo->swap)) {

		list_del_init(&bo->swap);

		++put_count;

	}

	if (!list_empty(&bo->lru)) {

		list_del_init(&bo->lru);

		++put_count;

	}

	/*

	 * TODO: Add a driver hook to delete from

	 * driver-specific LRU's here.

	 */

	return put_count;

}

static void ttm_bo_ref_bug(struct kref *list_kref)

{

	BUG();

}

void ttm_bo_list_ref_sub(struct ttm_buffer_object *bo, int count,

			 bool never_free)

{

//	kref_sub(&bo->list_kref, count,

//		 (never_free) ? ttm_bo_ref_bug : ttm_bo_release_list);

}

void ttm_bo_del_sub_from_lru(struct ttm_buffer_object *bo)

{

	int put_count;

	spin_lock(&bo->glob->lru_lock);

	put_count = ttm_bo_del_from_lru(bo);

	spin_unlock(&bo->glob->lru_lock);

	ttm_bo_list_ref_sub(bo, put_count, true);

}

EXPORT_SYMBOL(ttm_bo_del_sub_from_lru);

/*

 * Call bo->mutex locked.

 */

static int ttm_bo_add_ttm(struct ttm_buffer_object *bo, bool zero_alloc)

{

	struct ttm_bo_device *bdev = bo->bdev;

	struct ttm_bo_global *glob = bo->glob;

	int ret = 0;

	uint32_t page_flags = 0;

	TTM_ASSERT_LOCKED(&bo->mutex);

	bo->ttm = NULL;

	if (bdev->need_dma32)

		page_flags |= TTM_PAGE_FLAG_DMA32;

	switch (bo->type) {

	case ttm_bo_type_device:

		if (zero_alloc)

			page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;

	case ttm_bo_type_kernel:

		bo->ttm = bdev->driver->ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,

						      page_flags, glob->dummy_read_page);

		if (unlikely(bo->ttm == NULL))

			ret = -ENOMEM;

		break;

	case ttm_bo_type_sg:

		bo->ttm = bdev->driver->ttm_tt_create(bdev, bo->num_pages << PAGE_SHIFT,

						      page_flags | TTM_PAGE_FLAG_SG,

						      glob->dummy_read_page);

		if (unlikely(bo->ttm == NULL)) {

			ret = -ENOMEM;

			break;

		}

		bo->ttm->sg = bo->sg;

		break;

	default:

		pr_err("Illegal buffer object type\n");

		ret = -EINVAL;

		break;

	}

	return ret;

}

static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,

				  struct ttm_mem_reg *mem,

				  bool evict, bool interruptible,

				  bool no_wait_gpu)

{

	struct ttm_bo_device *bdev = bo->bdev;

	bool old_is_pci = ttm_mem_reg_is_pci(bdev, &bo->mem);

	bool new_is_pci = ttm_mem_reg_is_pci(bdev, mem);

	struct ttm_mem_type_manager *old_man = &bdev->man[bo->mem.mem_type];

	struct ttm_mem_type_manager *new_man = &bdev->man[mem->mem_type];

	int ret = 0;

	if (old_is_pci || new_is_pci ||

	    ((mem->placement & bo->mem.placement & TTM_PL_MASK_CACHING) == 0)) {

		ret = ttm_mem_io_lock(old_man, true);

		if (unlikely(ret != 0))

			goto out_err;

		ttm_bo_unmap_virtual_locked(bo);

		ttm_mem_io_unlock(old_man);

	}

	/*

	 * Create and bind a ttm if required.

	 */

	if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) {

		if (bo->ttm == NULL) {

			bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);

			ret = ttm_bo_add_ttm(bo, zero);

			if (ret)

				goto out_err;

		}

		ret = ttm_tt_set_placement_caching(bo->ttm, mem->placement);

		if (ret)

			goto out_err;

		if (mem->mem_type != TTM_PL_SYSTEM) {

			ret = ttm_tt_bind(bo->ttm, mem);

			if (ret)

				goto out_err;

		}

		if (bo->mem.mem_type == TTM_PL_SYSTEM) {

			if (bdev->driver->move_notify)

				bdev->driver->move_notify(bo, mem);

			bo->mem = *mem;

			mem->mm_node = NULL;

			goto moved;

		}

	}

	if (bdev->driver->move_notify)

		bdev->driver->move_notify(bo, mem);

	if (!(old_man->flags & TTM_MEMTYPE_FLAG_FIXED) &&

	    !(new_man->flags & TTM_MEMTYPE_FLAG_FIXED))

		ret = ttm_bo_move_ttm(bo, evict, no_wait_gpu, mem);

	else if (bdev->driver->move)

		ret = bdev->driver->move(bo, evict, interruptible,

					 no_wait_gpu, mem);

	else

		ret = ttm_bo_move_memcpy(bo, evict, no_wait_gpu, mem);

	if (ret) {

		if (bdev->driver->move_notify) {

			struct ttm_mem_reg tmp_mem = *mem;

			*mem = bo->mem;

			bo->mem = tmp_mem;

			bdev->driver->move_notify(bo, mem);

			bo->mem = *mem;

			*mem = tmp_mem;

		}

		goto out_err;

	}

moved:

	if (bo->evicted) {

		if (bdev->driver->invalidate_caches) {

			ret = bdev->driver->invalidate_caches(bdev, bo->mem.placement);

			if (ret)

				pr_err("Can not flush read caches\n");

		}

		bo->evicted = false;

	}

	if (bo->mem.mm_node) {

		bo->offset = (bo->mem.start << PAGE_SHIFT) +

		    bdev->man[bo->mem.mem_type].gpu_offset;

		bo->cur_placement = bo->mem.placement;

	} else

		bo->offset = 0;

	return 0;

out_err:

	new_man = &bdev->man[bo->mem.mem_type];

	if ((new_man->flags & TTM_MEMTYPE_FLAG_FIXED) && bo->ttm) {

		ttm_tt_unbind(bo->ttm);

		ttm_tt_destroy(bo->ttm);

		bo->ttm = NULL;

	}

	return ret;

}

/**

 * Call bo::reserved.

 * Will release GPU memory type usage on destruction.

 * This is the place to put in driver specific hooks to release

 * driver private resources.

 * Will release the bo::reserved lock.

 */

static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)

{

	if (bo->bdev->driver->move_notify)

		bo->bdev->driver->move_notify(bo, NULL);

	if (bo->ttm) {

		ttm_tt_unbind(bo->ttm);

		ttm_tt_destroy(bo->ttm);

		bo->ttm = NULL;

	}

	ttm_bo_mem_put(bo, &bo->mem);

	ww_mutex_unlock (&bo->resv->lock);

}

static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo)

{

	struct reservation_object_list *fobj;

	struct fence *fence;

	int i;

	fobj = reservation_object_get_list(bo->resv);

	fence = reservation_object_get_excl(bo->resv);

	if (fence && !fence->ops->signaled)

		fence_enable_sw_signaling(fence);

	for (i = 0; fobj && i < fobj->shared_count; ++i) {

		fence = rcu_dereference_protected(fobj->shared[i],

					reservation_object_held(bo->resv));

		if (!fence->ops->signaled)

			fence_enable_sw_signaling(fence);

	}

}

static void ttm_bo_cleanup_refs_or_queue(struct ttm_buffer_object *bo)

{

	struct ttm_bo_device *bdev = bo->bdev;

	struct ttm_bo_global *glob = bo->glob;

	int put_count;

	int ret;

	spin_lock(&glob->lru_lock);

	ret = __ttm_bo_reserve(bo, false, true, false, NULL);

	if (!ret) {

		if (!ttm_bo_wait(bo, false, false, true)) {

			put_count = ttm_bo_del_from_lru(bo);

			spin_unlock(&glob->lru_lock);

			ttm_bo_cleanup_memtype_use(bo);

			ttm_bo_list_ref_sub(bo, put_count, true);

			return;

		} else

			ttm_bo_flush_all_fences(bo);

		/*

		 * Make NO_EVICT bos immediately available to

		 * shrinkers, now that they are queued for

		 * destruction.

		 */

		if (bo->mem.placement & TTM_PL_FLAG_NO_EVICT) {

			bo->mem.placement &= ~TTM_PL_FLAG_NO_EVICT;

			ttm_bo_add_to_lru(bo);

		}

		__ttm_bo_unreserve(bo);

	}

	kref_get(&bo->list_kref);

	list_add_tail(&bo->ddestroy, &bdev->ddestroy);

	spin_unlock(&glob->lru_lock);

//	schedule_delayed_work(&bdev->wq,

//			      ((HZ / 100) < 1) ? 1 : HZ / 100);

}

/**

 * function ttm_bo_cleanup_refs_and_unlock

 * If bo idle, remove from delayed- and lru lists, and unref.

 * If not idle, do nothing.

 *

 * Must be called with lru_lock and reservation held, this function

 * will drop both before returning.

 *

 * @interruptible         Any sleeps should occur interruptibly.

 * @no_wait_gpu           Never wait for gpu. Return -EBUSY instead.

 */

static int ttm_bo_cleanup_refs_and_unlock(struct ttm_buffer_object *bo,

					  bool interruptible,

					  bool no_wait_gpu)

{

	struct ttm_bo_global *glob = bo->glob;

	int put_count;

	int ret;

	ret = ttm_bo_wait(bo, false, false, true);

	if (ret && !no_wait_gpu) {

		long lret;

		ww_mutex_unlock(&bo->resv->lock);

		spin_unlock(&glob->lru_lock);

		lret = reservation_object_wait_timeout_rcu(bo->resv,

							   true,

							   interruptible,

							   30 * HZ);

		if (lret < 0)

			return lret;

		else if (lret == 0)

			return -EBUSY;

		spin_lock(&glob->lru_lock);

		ret = __ttm_bo_reserve(bo, false, true, false, NULL);

		/*

		 * We raced, and lost, someone else holds the reservation now,

		 * and is probably busy in ttm_bo_cleanup_memtype_use.

		 *

		 * Even if it's not the case, because we finished waiting any

		 * delayed destruction would succeed, so just return success

		 * here.

		 */

		if (ret) {

			spin_unlock(&glob->lru_lock);

			return 0;

		}

		/*

		 * remove sync_obj with ttm_bo_wait, the wait should be

		 * finished, and no new wait object should have been added.

		 */

		ret = ttm_bo_wait(bo, false, false, true);

		WARN_ON(ret);

	}

	if (ret || unlikely(list_empty(&bo->ddestroy))) {

		__ttm_bo_unreserve(bo);

		spin_unlock(&glob->lru_lock);

		return ret;

	}

	put_count = ttm_bo_del_from_lru(bo);

	list_del_init(&bo->ddestroy);

	++put_count;

	spin_unlock(&glob->lru_lock);

	ttm_bo_cleanup_memtype_use(bo);

	ttm_bo_list_ref_sub(bo, put_count, true);

	return 0;

}

/**

 * Traverse the delayed list, and call ttm_bo_cleanup_refs on all

 * encountered buffers.

 */

static int ttm_bo_delayed_delete(struct ttm_bo_device *bdev, bool remove_all)

{

	struct ttm_bo_global *glob = bdev->glob;

	struct ttm_buffer_object *entry = NULL;

	int ret = 0;

	spin_lock(&glob->lru_lock);

	if (list_empty(&bdev->ddestroy))

		goto out_unlock;

	entry = list_first_entry(&bdev->ddestroy,

		struct ttm_buffer_object, ddestroy);

	kref_get(&entry->list_kref);

	for (;;) {

		struct ttm_buffer_object *nentry = NULL;

		if (entry->ddestroy.next != &bdev->ddestroy) {

			nentry = list_first_entry(&entry->ddestroy,

				struct ttm_buffer_object, ddestroy);

			kref_get(&nentry->list_kref);

		}

		ret = __ttm_bo_reserve(entry, false, true, false, NULL);

		if (remove_all && ret) {

			spin_unlock(&glob->lru_lock);

			ret = __ttm_bo_reserve(entry, false, false,

					       false, NULL);

			spin_lock(&glob->lru_lock);

		}

		if (!ret)

			ret = ttm_bo_cleanup_refs_and_unlock(entry, false,

							     !remove_all);

		else

			spin_unlock(&glob->lru_lock);

		kref_put(&entry->list_kref, ttm_bo_release_list);

		entry = nentry;

		if (ret || !entry)

			goto out;

		spin_lock(&glob->lru_lock);

		if (list_empty(&entry->ddestroy))

			break;

	}

out_unlock:

	spin_unlock(&glob->lru_lock);

out:

	if (entry)

		kref_put(&entry->list_kref, ttm_bo_release_list);

	return ret;

}

static void ttm_bo_delayed_workqueue(struct work_struct *work)

{

	struct ttm_bo_device *bdev =

	    container_of(work, struct ttm_bo_device, wq.work);

	if (ttm_bo_delayed_delete(bdev, false)) {

		schedule_delayed_work(&bdev->wq,

				      ((HZ / 100) < 1) ? 1 : HZ / 100);

	}

}

static void ttm_bo_release(struct kref *kref)

{

	struct ttm_buffer_object *bo =

	    container_of(kref, struct ttm_buffer_object, kref);

	struct ttm_bo_device *bdev = bo->bdev;

	struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];

	drm_vma_offset_remove(&bdev->vma_manager, &bo->vma_node);

	ttm_mem_io_lock(man, false);

	ttm_mem_io_free_vm(bo);

	ttm_mem_io_unlock(man);

	ttm_bo_cleanup_refs_or_queue(bo);

	kref_put(&bo->list_kref, ttm_bo_release_list);

}

void ttm_bo_unref(struct ttm_buffer_object **p_bo)

{

	struct ttm_buffer_object *bo = *p_bo;

	*p_bo = NULL;

	kref_put(&bo->kref, ttm_bo_release);

}

EXPORT_SYMBOL(ttm_bo_unref);

void ttm_bo_mem_put(struct ttm_buffer_object *bo, struct ttm_mem_reg *mem)

{

	struct ttm_mem_type_manager *man = &bo->bdev->man[mem->mem_type];

	if (mem->mm_node)

		(*man->func->put_node)(man, mem);

}

EXPORT_SYMBOL(ttm_bo_mem_put);

/**

 * Repeatedly evict memory from the LRU for @mem_type until we create enough

 * space, or we've evicted everything and there isn't enough space.

 */

static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,

					uint32_t mem_type,

					const struct ttm_place *place,

					struct ttm_mem_reg *mem,

					bool interruptible,

					bool no_wait_gpu)

{

	struct ttm_bo_device *bdev = bo->bdev;

	struct ttm_mem_type_manager *man = &bdev->man[mem_type];

	int ret;

	do {

		ret = (*man->func->get_node)(man, bo, place, mem);

		if (unlikely(ret != 0))

			return ret;

		if (mem->mm_node)

			break;

//		ret = ttm_mem_evict_first(bdev, mem_type,

//					  interruptible, no_wait_gpu);

//		if (unlikely(ret != 0))

//			return ret;

	} while (1);

	if (mem->mm_node == NULL)

		return -ENOMEM;

	mem->mem_type = mem_type;

	return 0;

}

static uint32_t ttm_bo_select_caching(struct ttm_mem_type_manager *man,

				      uint32_t cur_placement,

				      uint32_t proposed_placement)

{

	uint32_t caching = proposed_placement & TTM_PL_MASK_CACHING;

	uint32_t result = proposed_placement & ~TTM_PL_MASK_CACHING;

	/**

	 * Keep current caching if possible.

	 */

	if ((cur_placement & caching) != 0)

		result |= (cur_placement & caching);

	else if ((man->default_caching & caching) != 0)

		result |= man->default_caching;

	else if ((TTM_PL_FLAG_CACHED & caching) != 0)

		result |= TTM_PL_FLAG_CACHED;

	else if ((TTM_PL_FLAG_WC & caching) != 0)

		result |= TTM_PL_FLAG_WC;

	else if ((TTM_PL_FLAG_UNCACHED & caching) != 0)

		result |= TTM_PL_FLAG_UNCACHED;

	return result;

}

static bool ttm_bo_mt_compatible(struct ttm_mem_type_manager *man,

				 uint32_t mem_type,

				 const struct ttm_place *place,

				 uint32_t *masked_placement)

{

	uint32_t cur_flags = ttm_bo_type_flags(mem_type);

	if ((cur_flags & place->flags & TTM_PL_MASK_MEM) == 0)

		return false;

	if ((place->flags & man->available_caching) == 0)

		return false;

	cur_flags |= (place->flags & man->available_caching);

	*masked_placement = cur_flags;

	return true;

}

/**

 * Creates space for memory region @mem according to its type.

 *

 * This function first searches for free space in compatible memory types in

 * the priority order defined by the driver.  If free space isn't found, then

 * ttm_bo_mem_force_space is attempted in priority order to evict and find

 * space.

 */

int ttm_bo_mem_space(struct ttm_buffer_object *bo,

			struct ttm_placement *placement,

			struct ttm_mem_reg *mem,

			bool interruptible,

			bool no_wait_gpu)

{

	struct ttm_bo_device *bdev = bo->bdev;

	struct ttm_mem_type_manager *man;

	uint32_t mem_type = TTM_PL_SYSTEM;

	uint32_t cur_flags = 0;

	bool type_found = false;

	bool type_ok = false;

	bool has_erestartsys = false;

	int i, ret;

	mem->mm_node = NULL;

	for (i = 0; i < placement->num_placement; ++i) {

		const struct ttm_place *place = &placement->placement[i];

		ret = ttm_mem_type_from_place(place, &mem_type);

		if (ret)

			return ret;

		man = &bdev->man[mem_type];

		type_ok = ttm_bo_mt_compatible(man, mem_type, place,

						&cur_flags);

		if (!type_ok)

			continue;

		cur_flags = ttm_bo_select_caching(man, bo->mem.placement,

						  cur_flags);

		/*

		 * Use the access and other non-mapping-related flag bits from

		 * the memory placement flags to the current flags

		 */

		ttm_flag_masked(&cur_flags, place->flags,

				~TTM_PL_MASK_MEMTYPE);

		if (mem_type == TTM_PL_SYSTEM)

			break;

		if (man->has_type && man->use_type) {

			type_found = true;

			ret = (*man->func->get_node)(man, bo, place, mem);

			if (unlikely(ret))

				return ret;

		}

		if (mem->mm_node)

			break;

	}

	if ((type_ok && (mem_type == TTM_PL_SYSTEM)) || mem->mm_node) {

		mem->mem_type = mem_type;

		mem->placement = cur_flags;

		return 0;

	}

	if (!type_found)

		return -EINVAL;

	for (i = 0; i < placement->num_busy_placement; ++i) {

		const struct ttm_place *place = &placement->busy_placement[i];

		ret = ttm_mem_type_from_place(place, &mem_type);

		if (ret)

			return ret;

		man = &bdev->man[mem_type];

		if (!man->has_type)

			continue;

		if (!ttm_bo_mt_compatible(man, mem_type, place, &cur_flags))

			continue;

		cur_flags = ttm_bo_select_caching(man, bo->mem.placement,

						  cur_flags);

		/*

		 * Use the access and other non-mapping-related flag bits from

		 * the memory placement flags to the current flags

		 */

		ttm_flag_masked(&cur_flags, place->flags,

				~TTM_PL_MASK_MEMTYPE);

		if (mem_type == TTM_PL_SYSTEM) {

			mem->mem_type = mem_type;

			mem->placement = cur_flags;

			mem->mm_node = NULL;

			return 0;

		}

		ret = ttm_bo_mem_force_space(bo, mem_type, place, mem,

						interruptible, no_wait_gpu);

		if (ret == 0 && mem->mm_node) {

			mem->placement = cur_flags;

			return 0;

		}

		if (ret == -ERESTARTSYS)

			has_erestartsys = true;

	}

	ret = (has_erestartsys) ? -ERESTARTSYS : -ENOMEM;

	return ret;

}

EXPORT_SYMBOL(ttm_bo_mem_space);

static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,

			struct ttm_placement *placement,

			bool interruptible,

			bool no_wait_gpu)

{

	int ret = 0;

	struct ttm_mem_reg mem;

	lockdep_assert_held(&bo->resv->lock.base);

	/*

	 * FIXME: It's possible to pipeline buffer moves.

	 * Have the driver move function wait for idle when necessary,

	 * instead of doing it here.

	 */

	ret = ttm_bo_wait(bo, false, interruptible, no_wait_gpu);

	if (ret)

		return ret;

	mem.num_pages = bo->num_pages;

	mem.size = mem.num_pages << PAGE_SHIFT;

	mem.page_alignment = bo->mem.page_alignment;

	mem.bus.io_reserved_vm = false;

	mem.bus.io_reserved_count = 0;

	/*

	 * Determine where to move the buffer.

	 */

	ret = ttm_bo_mem_space(bo, placement, &mem,

			       interruptible, no_wait_gpu);

	if (ret)

		goto out_unlock;

	ret = ttm_bo_handle_move_mem(bo, &mem, false,

				     interruptible, no_wait_gpu);

out_unlock:

	if (ret && mem.mm_node)

		ttm_bo_mem_put(bo, &mem);

	return ret;

}

static bool ttm_bo_mem_compat(struct ttm_placement *placement,

			      struct ttm_mem_reg *mem,

			      uint32_t *new_flags)

{

	int i;

	for (i = 0; i < placement->num_placement; i++) {

		const struct ttm_place *heap = &placement->placement[i];

		if (mem->mm_node &&

		    (mem->start < heap->fpfn ||

		     (heap->lpfn != 0 && (mem->start + mem->num_pages) > heap->lpfn)))

			continue;

		*new_flags = heap->flags;

		if ((*new_flags & mem->placement & TTM_PL_MASK_CACHING) &&

		    (*new_flags & mem->placement & TTM_PL_MASK_MEM))

			return true;

	}

	for (i = 0; i < placement->num_busy_placement; i++) {

		const struct ttm_place *heap = &placement->busy_placement[i];

		if (mem->mm_node &&

		    (mem->start < heap->fpfn ||

		     (heap->lpfn != 0 && (mem->start + mem->num_pages) > heap->lpfn)))

			continue;

		*new_flags = heap->flags;

		if ((*new_flags & mem->placement & TTM_PL_MASK_CACHING) &&

		    (*new_flags & mem->placement & TTM_PL_MASK_MEM))

			return true;

	}

	return false;

}

int ttm_bo_validate(struct ttm_buffer_object *bo,

			struct ttm_placement *placement,

			bool interruptible,

			bool no_wait_gpu)

{

	int ret;

	uint32_t new_flags;

	lockdep_assert_held(&bo->resv->lock.base);

	/*

	 * Check whether we need to move buffer.

	 */

	if (!ttm_bo_mem_compat(placement, &bo->mem, &new_flags)) {

		ret = ttm_bo_move_buffer(bo, placement, interruptible,

					 no_wait_gpu);

		if (ret)

			return ret;

	} else {

		/*

		 * Use the access and other non-mapping-related flag bits from

		 * the compatible memory placement flags to the active flags

		 */

		ttm_flag_masked(&bo->mem.placement, new_flags,

				~TTM_PL_MASK_MEMTYPE);

	}

	/*

	 * We might need to add a TTM.

	 */

	if (bo->mem.mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {

		ret = ttm_bo_add_ttm(bo, true);

		if (ret)

			return ret;

	}

	return 0;

}

EXPORT_SYMBOL(ttm_bo_validate);

int ttm_bo_init(struct ttm_bo_device *bdev,

        struct ttm_buffer_object *bo,

        unsigned long size,

        enum ttm_bo_type type,

        struct ttm_placement *placement,

        uint32_t page_alignment,

        bool interruptible,

        struct file *persistent_swap_storage,

        size_t acc_size,

        struct sg_table *sg,

		struct reservation_object *resv,

        void (*destroy) (struct ttm_buffer_object *))

{

    int ret = 0;

    unsigned long num_pages;

    bool locked;

    num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;

    if (num_pages == 0) {

        pr_err("Illegal buffer object size\n");

        if (destroy)

            (*destroy)(bo);

        else

            kfree(bo);

        return -EINVAL;

    }

    bo->destroy = destroy;

    kref_init(&bo->kref);

    kref_init(&bo->list_kref);

	atomic_set(&bo->cpu_writers, 0);

    INIT_LIST_HEAD(&bo->lru);

    INIT_LIST_HEAD(&bo->ddestroy);

    INIT_LIST_HEAD(&bo->swap);

    INIT_LIST_HEAD(&bo->io_reserve_lru);

    mutex_init(&bo->wu_mutex);

    bo->bdev = bdev;

    bo->glob = bdev->glob;

    bo->type = type;

    bo->num_pages = num_pages;

    bo->mem.size = num_pages << PAGE_SHIFT;

    bo->mem.mem_type = TTM_PL_SYSTEM;

    bo->mem.num_pages = bo->num_pages;

    bo->mem.mm_node = NULL;

    bo->mem.page_alignment = page_alignment;

    bo->mem.bus.io_reserved_vm = false;

    bo->mem.bus.io_reserved_count = 0;

    bo->priv_flags = 0;

    bo->mem.placement = (TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED);

    bo->persistent_swap_storage = persistent_swap_storage;

    bo->acc_size = acc_size;

    bo->sg = sg;

	if (resv) {

		bo->resv = resv;

		lockdep_assert_held(&bo->resv->lock.base);

	} else {

		bo->resv = &bo->ttm_resv;

		reservation_object_init(&bo->ttm_resv);

	}

	atomic_inc(&bo->glob->bo_count);

    drm_vma_node_reset(&bo->vma_node);

    /*

     * For ttm_bo_type_device buffers, allocate

     * address space from the device.

     */

	if (bo->type == ttm_bo_type_device ||

	    bo->type == ttm_bo_type_sg)

		ret = drm_vma_offset_add(&bdev->vma_manager, &bo->vma_node,

					 bo->mem.num_pages);

	/* passed reservation objects should already be locked,

	 * since otherwise lockdep will be angered in radeon.

	 */

	if (!resv) {

		locked = ww_mutex_trylock(&bo->resv->lock);

		WARN_ON(!locked);

	}

	if (likely(!ret))

		ret = ttm_bo_validate(bo, placement, interruptible, false);

	if (!resv)

		ttm_bo_unreserve(bo);

	if (unlikely(ret))

		ttm_bo_unref(&bo);

    return ret;

}

EXPORT_SYMBOL(ttm_bo_init);

size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,

		       unsigned long bo_size,

		       unsigned struct_size)

{

	unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;

	size_t size = 0;

	size += ttm_round_pot(struct_size);

	size += PAGE_ALIGN(npages * sizeof(void *));

	size += ttm_round_pot(sizeof(struct ttm_tt));

	return size;

}

EXPORT_SYMBOL(ttm_bo_acc_size);

size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,

			   unsigned long bo_size,

			   unsigned struct_size)

{

	unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;

	size_t size = 0;

	size += ttm_round_pot(struct_size);

	size += PAGE_ALIGN(npages * sizeof(void *));

	size += PAGE_ALIGN(npages * sizeof(dma_addr_t));

	size += ttm_round_pot(sizeof(struct ttm_dma_tt));

	return size;

}

EXPORT_SYMBOL(ttm_bo_dma_acc_size);

int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,

			unsigned long p_size)

{

	int ret = -EINVAL;

	struct ttm_mem_type_manager *man;

	BUG_ON(type >= TTM_NUM_MEM_TYPES);

	man = &bdev->man[type];

	BUG_ON(man->has_type);

	man->io_reserve_fastpath = true;

	man->use_io_reserve_lru = false;

	mutex_init(&man->io_reserve_mutex);

	INIT_LIST_HEAD(&man->io_reserve_lru);

	ret = bdev->driver->init_mem_type(bdev, type, man);

	if (ret)

		return ret;

	man->bdev = bdev;

	ret = 0;

	if (type != TTM_PL_SYSTEM) {

		ret = (*man->func->init)(man, p_size);

		if (ret)

			return ret;

	}

	man->has_type = true;

	man->use_type = true;

	man->size = p_size;

	INIT_LIST_HEAD(&man->lru);

	return 0;

}

EXPORT_SYMBOL(ttm_bo_init_mm);

void ttm_bo_global_release(struct drm_global_reference *ref)

{

	struct ttm_bo_global *glob = ref->object;

}

EXPORT_SYMBOL(ttm_bo_global_release);

int ttm_bo_global_init(struct drm_global_reference *ref)

{

    struct ttm_bo_global_ref *bo_ref =

        container_of(ref, struct ttm_bo_global_ref, ref);

    struct ttm_bo_global *glob = ref->object;

    int ret;

    mutex_init(&glob->device_list_mutex);

    spin_lock_init(&glob->lru_lock);

    glob->mem_glob = bo_ref->mem_glob;

	glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32);

    if (unlikely(glob->dummy_read_page == NULL)) {

        ret = -ENOMEM;

        goto out_no_drp;

    }

    INIT_LIST_HEAD(&glob->swap_lru);

    INIT_LIST_HEAD(&glob->device_list);

    atomic_set(&glob->bo_count, 0);

    return 0;

out_no_drp:

    kfree(glob);

    return ret;

}

EXPORT_SYMBOL(ttm_bo_global_init);

int ttm_bo_device_init(struct ttm_bo_device *bdev,

		       struct ttm_bo_global *glob,

		       struct ttm_bo_driver *driver,

		       struct address_space *mapping,

		       uint64_t file_page_offset,

		       bool need_dma32)

{

	int ret = -EINVAL;

	bdev->driver = driver;

	memset(bdev->man, 0, sizeof(bdev->man));

	/*

	 * Initialize the system memory buffer type.

	 * Other types need to be driver / IOCTL initialized.

	 */