drivers/gpu/drm/i915/gem/i915_gem_object.h - linux - Git at Google

 /*
  * SPDX-License-Identifier: MIT
  *
  * Copyright © 2016 Intel Corporation
  */

 #ifndef __I915_GEM_OBJECT_H__
 #define __I915_GEM_OBJECT_H__

 #include <drm/drm_gem.h>
 #include <drm/drm_file.h>
 #include <drm/drm_device.h>

 #include <drm/i915_drm.h>

 #include "i915_gem_object_types.h"

 #include "i915_gem_gtt.h"

 void i915_gem_init__objects(struct drm_i915_private *i915);

 struct drm_i915_gem_object *i915_gem_object_alloc(void);
 void i915_gem_object_free(struct drm_i915_gem_object *obj);

 void i915_gem_object_init(struct drm_i915_gem_object *obj,
 			  const struct drm_i915_gem_object_ops *ops);
 struct drm_i915_gem_object *
 i915_gem_object_create_shmem(struct drm_i915_private *i915, u64 size);
 struct drm_i915_gem_object *
 i915_gem_object_create_shmem_from_data(struct drm_i915_private *i915,
 				       const void *data, size_t size);

 extern const struct drm_i915_gem_object_ops i915_gem_shmem_ops;
 void __i915_gem_object_release_shmem(struct drm_i915_gem_object *obj,
 				     struct sg_table *pages,
 				     bool needs_clflush);

 int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align);

 void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file);
 void i915_gem_free_object(struct drm_gem_object *obj);

 void i915_gem_flush_free_objects(struct drm_i915_private *i915);

 struct sg_table *
 __i915_gem_object_unset_pages(struct drm_i915_gem_object *obj);
 void i915_gem_object_truncate(struct drm_i915_gem_object *obj);

 /**
  * i915_gem_object_lookup_rcu - look up a temporary GEM object from its handle
  * @filp: DRM file private date
  * @handle: userspace handle
  *
  * Returns:
  *
  * A pointer to the object named by the handle if such exists on @filp, NULL
  * otherwise. This object is only valid whilst under the RCU read lock, and
  * note carefully the object may be in the process of being destroyed.
  */
 static inline struct drm_i915_gem_object *
 i915_gem_object_lookup_rcu(struct drm_file *file, u32 handle)
 {
 #ifdef CONFIG_LOCKDEP
 	WARN_ON(debug_locks && !lock_is_held(&rcu_lock_map));
 #endif
 	return idr_find(&file->object_idr, handle);
 }

 static inline struct drm_i915_gem_object *
 i915_gem_object_lookup(struct drm_file *file, u32 handle)
 {
 	struct drm_i915_gem_object *obj;

 	rcu_read_lock();
 	obj = i915_gem_object_lookup_rcu(file, handle);
 	if (obj && !kref_get_unless_zero(&obj->base.refcount))
 		obj = NULL;
 	rcu_read_unlock();

 	return obj;
 }

 __deprecated
 extern struct drm_gem_object *
 drm_gem_object_lookup(struct drm_file *file, u32 handle);

 __attribute__((nonnull))
 static inline struct drm_i915_gem_object *
 i915_gem_object_get(struct drm_i915_gem_object *obj)
 {
 	drm_gem_object_get(&obj->base);
 	return obj;
 }

 __attribute__((nonnull))
 static inline void
 i915_gem_object_put(struct drm_i915_gem_object *obj)
 {
 	__drm_gem_object_put(&obj->base);
 }

 #define assert_object_held(obj) reservation_object_assert_held((obj)->base.resv)

 static inline void i915_gem_object_lock(struct drm_i915_gem_object *obj)
 {
 	reservation_object_lock(obj->base.resv, NULL);
 }

 static inline int
 i915_gem_object_lock_interruptible(struct drm_i915_gem_object *obj)
 {
 	return reservation_object_lock_interruptible(obj->base.resv, NULL);
 }

 static inline void i915_gem_object_unlock(struct drm_i915_gem_object *obj)
 {
 	reservation_object_unlock(obj->base.resv);
 }

 struct dma_fence *
 i915_gem_object_lock_fence(struct drm_i915_gem_object *obj);
 void i915_gem_object_unlock_fence(struct drm_i915_gem_object *obj,
 				  struct dma_fence *fence);

 static inline void
 i915_gem_object_set_readonly(struct drm_i915_gem_object *obj)
 {
 	obj->base.vma_node.readonly = true;
 }

 static inline bool
 i915_gem_object_is_readonly(const struct drm_i915_gem_object *obj)
 {
 	return obj->base.vma_node.readonly;
 }

 static inline bool
 i915_gem_object_has_struct_page(const struct drm_i915_gem_object *obj)
 {
 	return obj->ops->flags & I915_GEM_OBJECT_HAS_STRUCT_PAGE;
 }

 static inline bool
 i915_gem_object_is_shrinkable(const struct drm_i915_gem_object *obj)
 {
 	return obj->ops->flags & I915_GEM_OBJECT_IS_SHRINKABLE;
 }

 static inline bool
 i915_gem_object_is_proxy(const struct drm_i915_gem_object *obj)
 {
 	return obj->ops->flags & I915_GEM_OBJECT_IS_PROXY;
 }

 static inline bool
 i915_gem_object_needs_async_cancel(const struct drm_i915_gem_object *obj)
 {
 	return obj->ops->flags & I915_GEM_OBJECT_ASYNC_CANCEL;
 }

 static inline bool
 i915_gem_object_is_active(const struct drm_i915_gem_object *obj)
 {
 	return READ_ONCE(obj->active_count);
 }

 static inline bool
 i915_gem_object_is_framebuffer(const struct drm_i915_gem_object *obj)
 {
 	return READ_ONCE(obj->framebuffer_references);
 }

 static inline unsigned int
 i915_gem_object_get_tiling(const struct drm_i915_gem_object *obj)
 {
 	return obj->tiling_and_stride & TILING_MASK;
 }

 static inline bool
 i915_gem_object_is_tiled(const struct drm_i915_gem_object *obj)
 {
 	return i915_gem_object_get_tiling(obj) != I915_TILING_NONE;
 }

 static inline unsigned int
 i915_gem_object_get_stride(const struct drm_i915_gem_object *obj)
 {
 	return obj->tiling_and_stride & STRIDE_MASK;
 }

 static inline unsigned int
 i915_gem_tile_height(unsigned int tiling)
 {
 	GEM_BUG_ON(!tiling);
 	return tiling == I915_TILING_Y ? 32 : 8;
 }

 static inline unsigned int
 i915_gem_object_get_tile_height(const struct drm_i915_gem_object *obj)
 {
 	return i915_gem_tile_height(i915_gem_object_get_tiling(obj));
 }

 static inline unsigned int
 i915_gem_object_get_tile_row_size(const struct drm_i915_gem_object *obj)
 {
 	return (i915_gem_object_get_stride(obj) *
 		i915_gem_object_get_tile_height(obj));
 }

 int i915_gem_object_set_tiling(struct drm_i915_gem_object *obj,
 			       unsigned int tiling, unsigned int stride);

 struct scatterlist *
 i915_gem_object_get_sg(struct drm_i915_gem_object *obj,
 		       unsigned int n, unsigned int *offset);

 struct page *
 i915_gem_object_get_page(struct drm_i915_gem_object *obj,
 			 unsigned int n);

 struct page *
 i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj,
 			       unsigned int n);

 dma_addr_t
 i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj,
 				    unsigned long n,
 				    unsigned int *len);

 dma_addr_t
 i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,
 				unsigned long n);

 void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
 				 struct sg_table *pages,
 				 unsigned int sg_page_sizes);

 int ____i915_gem_object_get_pages(struct drm_i915_gem_object *obj);
 int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj);

 static inline int __must_check
 i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
 {
 	might_lock(&obj->mm.lock);

 	if (atomic_inc_not_zero(&obj->mm.pages_pin_count))
 		return 0;

 	return __i915_gem_object_get_pages(obj);
 }

 static inline bool
 i915_gem_object_has_pages(struct drm_i915_gem_object *obj)
 {
 	return !IS_ERR_OR_NULL(READ_ONCE(obj->mm.pages));
 }

 static inline void
 __i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
 {
 	GEM_BUG_ON(!i915_gem_object_has_pages(obj));

 	atomic_inc(&obj->mm.pages_pin_count);
 }

 static inline bool
 i915_gem_object_has_pinned_pages(struct drm_i915_gem_object *obj)
 {
 	return atomic_read(&obj->mm.pages_pin_count);
 }

 static inline void
 __i915_gem_object_unpin_pages(struct drm_i915_gem_object *obj)
 {
 	GEM_BUG_ON(!i915_gem_object_has_pages(obj));
 	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));

 	atomic_dec(&obj->mm.pages_pin_count);
 }

 static inline void
 i915_gem_object_unpin_pages(struct drm_i915_gem_object *obj)
 {
 	__i915_gem_object_unpin_pages(obj);
 }

 enum i915_mm_subclass { /* lockdep subclass for obj->mm.lock/struct_mutex */
 	I915_MM_NORMAL = 0,
 	I915_MM_SHRINKER /* called "recursively" from direct-reclaim-esque */
 };

 int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj,
 				enum i915_mm_subclass subclass);
 void i915_gem_object_truncate(struct drm_i915_gem_object *obj);
 void i915_gem_object_writeback(struct drm_i915_gem_object *obj);

 enum i915_map_type {
 	I915_MAP_WB = 0,
 	I915_MAP_WC,
 #define I915_MAP_OVERRIDE BIT(31)
 	I915_MAP_FORCE_WB = I915_MAP_WB | I915_MAP_OVERRIDE,
 	I915_MAP_FORCE_WC = I915_MAP_WC | I915_MAP_OVERRIDE,
 };

 /**
  * i915_gem_object_pin_map - return a contiguous mapping of the entire object
  * @obj: the object to map into kernel address space
  * @type: the type of mapping, used to select pgprot_t
  *
  * Calls i915_gem_object_pin_pages() to prevent reaping of the object's
  * pages and then returns a contiguous mapping of the backing storage into
  * the kernel address space. Based on the @type of mapping, the PTE will be
  * set to either WriteBack or WriteCombine (via pgprot_t).
  *
  * The caller is responsible for calling i915_gem_object_unpin_map() when the
  * mapping is no longer required.
  *
  * Returns the pointer through which to access the mapped object, or an
  * ERR_PTR() on error.
  */
 void *__must_check i915_gem_object_pin_map(struct drm_i915_gem_object *obj,
 					   enum i915_map_type type);

 void __i915_gem_object_flush_map(struct drm_i915_gem_object *obj,
 				 unsigned long offset,
 				 unsigned long size);
 static inline void i915_gem_object_flush_map(struct drm_i915_gem_object *obj)
 {
 	__i915_gem_object_flush_map(obj, 0, obj->base.size);
 }

 /**
  * i915_gem_object_unpin_map - releases an earlier mapping
  * @obj: the object to unmap
  *
  * After pinning the object and mapping its pages, once you are finished
  * with your access, call i915_gem_object_unpin_map() to release the pin
  * upon the mapping. Once the pin count reaches zero, that mapping may be
  * removed.
  */
 static inline void i915_gem_object_unpin_map(struct drm_i915_gem_object *obj)
 {
 	i915_gem_object_unpin_pages(obj);
 }

 void __i915_gem_object_release_mmap(struct drm_i915_gem_object *obj);
 void i915_gem_object_release_mmap(struct drm_i915_gem_object *obj);

 void
 i915_gem_object_flush_write_domain(struct drm_i915_gem_object *obj,
 				   unsigned int flush_domains);

 int i915_gem_object_prepare_read(struct drm_i915_gem_object *obj,
 				 unsigned int *needs_clflush);
 int i915_gem_object_prepare_write(struct drm_i915_gem_object *obj,
 				  unsigned int *needs_clflush);
 #define CLFLUSH_BEFORE	BIT(0)
 #define CLFLUSH_AFTER	BIT(1)
 #define CLFLUSH_FLAGS	(CLFLUSH_BEFORE | CLFLUSH_AFTER)

 static inline void
 i915_gem_object_finish_access(struct drm_i915_gem_object *obj)
 {
 	i915_gem_object_unpin_pages(obj);
 	i915_gem_object_unlock(obj);
 }

 static inline struct intel_engine_cs *
 i915_gem_object_last_write_engine(struct drm_i915_gem_object *obj)
 {
 	struct intel_engine_cs *engine = NULL;
 	struct dma_fence *fence;

 	rcu_read_lock();
 	fence = reservation_object_get_excl_rcu(obj->base.resv);
 	rcu_read_unlock();

 	if (fence && dma_fence_is_i915(fence) && !dma_fence_is_signaled(fence))
 		engine = to_request(fence)->engine;
 	dma_fence_put(fence);

 	return engine;
 }

 void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj,
 					 unsigned int cache_level);
 void i915_gem_object_flush_if_display(struct drm_i915_gem_object *obj);

 int __must_check
 i915_gem_object_set_to_wc_domain(struct drm_i915_gem_object *obj, bool write);
 int __must_check
 i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write);
 int __must_check
 i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write);
 struct i915_vma * __must_check
 i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj,
 				     u32 alignment,
 				     const struct i915_ggtt_view *view,
 				     unsigned int flags);
 void i915_gem_object_unpin_from_display_plane(struct i915_vma *vma);

 static inline bool cpu_write_needs_clflush(struct drm_i915_gem_object *obj)
 {
 	if (obj->cache_dirty)
 		return false;

 	if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE))
 		return true;

 	return obj->pin_global; /* currently in use by HW, keep flushed */
 }

 static inline void __start_cpu_write(struct drm_i915_gem_object *obj)
 {
 	obj->read_domains = I915_GEM_DOMAIN_CPU;
 	obj->write_domain = I915_GEM_DOMAIN_CPU;
 	if (cpu_write_needs_clflush(obj))
 		obj->cache_dirty = true;
 }

 int i915_gem_object_wait(struct drm_i915_gem_object *obj,
 			 unsigned int flags,
 			 long timeout);
 int i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
 				  unsigned int flags,
 				  const struct i915_sched_attr *attr);
 #define I915_PRIORITY_DISPLAY I915_USER_PRIORITY(I915_PRIORITY_MAX)

 #endif
	/*
	* SPDX-License-Identifier: MIT
	*
	* Copyright © 2016 Intel Corporation
	*/

	#ifndef __I915_GEM_OBJECT_H__
	#define __I915_GEM_OBJECT_H__

	#include <drm/drm_gem.h>
	#include <drm/drm_file.h>
	#include <drm/drm_device.h>

	#include <drm/i915_drm.h>

	#include "i915_gem_object_types.h"

	#include "i915_gem_gtt.h"

	void i915_gem_init__objects(struct drm_i915_private *i915);

	struct drm_i915_gem_object *i915_gem_object_alloc(void);
	void i915_gem_object_free(struct drm_i915_gem_object *obj);

	void i915_gem_object_init(struct drm_i915_gem_object *obj,
	const struct drm_i915_gem_object_ops *ops);
	struct drm_i915_gem_object *
	i915_gem_object_create_shmem(struct drm_i915_private *i915, u64 size);
	struct drm_i915_gem_object *
	i915_gem_object_create_shmem_from_data(struct drm_i915_private *i915,
	const void *data, size_t size);

	extern const struct drm_i915_gem_object_ops i915_gem_shmem_ops;
	void __i915_gem_object_release_shmem(struct drm_i915_gem_object *obj,
	struct sg_table *pages,
	bool needs_clflush);

	int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align);

	void i915_gem_close_object(struct drm_gem_object gem, struct drm_file file);
	void i915_gem_free_object(struct drm_gem_object *obj);

	void i915_gem_flush_free_objects(struct drm_i915_private *i915);

	struct sg_table *
	__i915_gem_object_unset_pages(struct drm_i915_gem_object *obj);
	void i915_gem_object_truncate(struct drm_i915_gem_object *obj);

	/**
	* i915_gem_object_lookup_rcu - look up a temporary GEM object from its handle
	* @filp: DRM file private date
	* @handle: userspace handle
	*
	* Returns:
	*
	* A pointer to the object named by the handle if such exists on @filp, NULL
	* otherwise. This object is only valid whilst under the RCU read lock, and
	* note carefully the object may be in the process of being destroyed.
	*/
	static inline struct drm_i915_gem_object *
	i915_gem_object_lookup_rcu(struct drm_file *file, u32 handle)
	{
	#ifdef CONFIG_LOCKDEP
	WARN_ON(debug_locks && !lock_is_held(&rcu_lock_map));
	#endif
	return idr_find(&file->object_idr, handle);
	}

	static inline struct drm_i915_gem_object *
	i915_gem_object_lookup(struct drm_file *file, u32 handle)
	{
	struct drm_i915_gem_object *obj;

	rcu_read_lock();
	obj = i915_gem_object_lookup_rcu(file, handle);
	if (obj && !kref_get_unless_zero(&obj->base.refcount))
	obj = NULL;
	rcu_read_unlock();

	return obj;
	}

	__deprecated
	extern struct drm_gem_object *
	drm_gem_object_lookup(struct drm_file *file, u32 handle);

	__attribute__((nonnull))
	static inline struct drm_i915_gem_object *
	i915_gem_object_get(struct drm_i915_gem_object *obj)
	{
	drm_gem_object_get(&obj->base);
	return obj;
	}

	__attribute__((nonnull))
	static inline void
	i915_gem_object_put(struct drm_i915_gem_object *obj)
	{
	__drm_gem_object_put(&obj->base);
	}

	#define assert_object_held(obj) reservation_object_assert_held((obj)->base.resv)

	static inline void i915_gem_object_lock(struct drm_i915_gem_object *obj)
	{
	reservation_object_lock(obj->base.resv, NULL);
	}

	static inline int
	i915_gem_object_lock_interruptible(struct drm_i915_gem_object *obj)
	{
	return reservation_object_lock_interruptible(obj->base.resv, NULL);
	}

	static inline void i915_gem_object_unlock(struct drm_i915_gem_object *obj)
	{
	reservation_object_unlock(obj->base.resv);
	}

	struct dma_fence *
	i915_gem_object_lock_fence(struct drm_i915_gem_object *obj);
	void i915_gem_object_unlock_fence(struct drm_i915_gem_object *obj,
	struct dma_fence *fence);

	static inline void
	i915_gem_object_set_readonly(struct drm_i915_gem_object *obj)
	{
	obj->base.vma_node.readonly = true;
	}

	static inline bool
	i915_gem_object_is_readonly(const struct drm_i915_gem_object *obj)
	{
	return obj->base.vma_node.readonly;
	}

	static inline bool
	i915_gem_object_has_struct_page(const struct drm_i915_gem_object *obj)
	{
	return obj->ops->flags & I915_GEM_OBJECT_HAS_STRUCT_PAGE;
	}

	static inline bool
	i915_gem_object_is_shrinkable(const struct drm_i915_gem_object *obj)
	{
	return obj->ops->flags & I915_GEM_OBJECT_IS_SHRINKABLE;
	}

	static inline bool
	i915_gem_object_is_proxy(const struct drm_i915_gem_object *obj)
	{
	return obj->ops->flags & I915_GEM_OBJECT_IS_PROXY;
	}

	static inline bool
	i915_gem_object_needs_async_cancel(const struct drm_i915_gem_object *obj)
	{
	return obj->ops->flags & I915_GEM_OBJECT_ASYNC_CANCEL;
	}

	static inline bool
	i915_gem_object_is_active(const struct drm_i915_gem_object *obj)
	{
	return READ_ONCE(obj->active_count);
	}

	static inline bool
	i915_gem_object_is_framebuffer(const struct drm_i915_gem_object *obj)
	{
	return READ_ONCE(obj->framebuffer_references);
	}

	static inline unsigned int
	i915_gem_object_get_tiling(const struct drm_i915_gem_object *obj)
	{
	return obj->tiling_and_stride & TILING_MASK;
	}

	static inline bool
	i915_gem_object_is_tiled(const struct drm_i915_gem_object *obj)
	{
	return i915_gem_object_get_tiling(obj) != I915_TILING_NONE;
	}

	static inline unsigned int
	i915_gem_object_get_stride(const struct drm_i915_gem_object *obj)
	{
	return obj->tiling_and_stride & STRIDE_MASK;
	}

	static inline unsigned int
	i915_gem_tile_height(unsigned int tiling)
	{
	GEM_BUG_ON(!tiling);
	return tiling == I915_TILING_Y ? 32 : 8;
	}

	static inline unsigned int
	i915_gem_object_get_tile_height(const struct drm_i915_gem_object *obj)
	{
	return i915_gem_tile_height(i915_gem_object_get_tiling(obj));
	}

	static inline unsigned int
	i915_gem_object_get_tile_row_size(const struct drm_i915_gem_object *obj)
	{
	return (i915_gem_object_get_stride(obj) *
	i915_gem_object_get_tile_height(obj));
	}

	int i915_gem_object_set_tiling(struct drm_i915_gem_object *obj,
	unsigned int tiling, unsigned int stride);

	struct scatterlist *
	i915_gem_object_get_sg(struct drm_i915_gem_object *obj,
	unsigned int n, unsigned int *offset);

	struct page *
	i915_gem_object_get_page(struct drm_i915_gem_object *obj,
	unsigned int n);

	struct page *
	i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj,
	unsigned int n);

	dma_addr_t
	i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj,
	unsigned long n,
	unsigned int *len);

	dma_addr_t
	i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,
	unsigned long n);

	void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
	struct sg_table *pages,
	unsigned int sg_page_sizes);

	int ____i915_gem_object_get_pages(struct drm_i915_gem_object *obj);
	int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj);

	static inline int __must_check
	i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
	{
	might_lock(&obj->mm.lock);

	if (atomic_inc_not_zero(&obj->mm.pages_pin_count))
	return 0;

	return __i915_gem_object_get_pages(obj);
	}

	static inline bool
	i915_gem_object_has_pages(struct drm_i915_gem_object *obj)
	{
	return !IS_ERR_OR_NULL(READ_ONCE(obj->mm.pages));
	}

	static inline void
	__i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
	{
	GEM_BUG_ON(!i915_gem_object_has_pages(obj));

	atomic_inc(&obj->mm.pages_pin_count);
	}

	static inline bool
	i915_gem_object_has_pinned_pages(struct drm_i915_gem_object *obj)
	{
	return atomic_read(&obj->mm.pages_pin_count);
	}

	static inline void
	__i915_gem_object_unpin_pages(struct drm_i915_gem_object *obj)
	{
	GEM_BUG_ON(!i915_gem_object_has_pages(obj));
	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));

	atomic_dec(&obj->mm.pages_pin_count);
	}

	static inline void
	i915_gem_object_unpin_pages(struct drm_i915_gem_object *obj)
	{
	__i915_gem_object_unpin_pages(obj);
	}

	enum i915_mm_subclass { /* lockdep subclass for obj->mm.lock/struct_mutex */
	I915_MM_NORMAL = 0,
	I915_MM_SHRINKER /* called "recursively" from direct-reclaim-esque */
	};

	int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj,
	enum i915_mm_subclass subclass);
	void i915_gem_object_truncate(struct drm_i915_gem_object *obj);
	void i915_gem_object_writeback(struct drm_i915_gem_object *obj);

	enum i915_map_type {
	I915_MAP_WB = 0,
	I915_MAP_WC,
	#define I915_MAP_OVERRIDE BIT(31)
	I915_MAP_FORCE_WB = I915_MAP_WB \| I915_MAP_OVERRIDE,
	I915_MAP_FORCE_WC = I915_MAP_WC \| I915_MAP_OVERRIDE,
	};

	/**
	* i915_gem_object_pin_map - return a contiguous mapping of the entire object
	* @obj: the object to map into kernel address space
	* @type: the type of mapping, used to select pgprot_t
	*
	* Calls i915_gem_object_pin_pages() to prevent reaping of the object's
	* pages and then returns a contiguous mapping of the backing storage into
	* the kernel address space. Based on the @type of mapping, the PTE will be
	* set to either WriteBack or WriteCombine (via pgprot_t).
	*
	* The caller is responsible for calling i915_gem_object_unpin_map() when the
	* mapping is no longer required.
	*
	* Returns the pointer through which to access the mapped object, or an
	* ERR_PTR() on error.
	*/
	void __must_check i915_gem_object_pin_map(struct drm_i915_gem_object obj,
	enum i915_map_type type);

	void __i915_gem_object_flush_map(struct drm_i915_gem_object *obj,
	unsigned long offset,
	unsigned long size);
	static inline void i915_gem_object_flush_map(struct drm_i915_gem_object *obj)
	{
	__i915_gem_object_flush_map(obj, 0, obj->base.size);
	}

	/**
	* i915_gem_object_unpin_map - releases an earlier mapping
	* @obj: the object to unmap
	*
	* After pinning the object and mapping its pages, once you are finished
	* with your access, call i915_gem_object_unpin_map() to release the pin
	* upon the mapping. Once the pin count reaches zero, that mapping may be
	* removed.
	*/
	static inline void i915_gem_object_unpin_map(struct drm_i915_gem_object *obj)
	{
	i915_gem_object_unpin_pages(obj);
	}

	void __i915_gem_object_release_mmap(struct drm_i915_gem_object *obj);
	void i915_gem_object_release_mmap(struct drm_i915_gem_object *obj);

	void
	i915_gem_object_flush_write_domain(struct drm_i915_gem_object *obj,
	unsigned int flush_domains);

	int i915_gem_object_prepare_read(struct drm_i915_gem_object *obj,
	unsigned int *needs_clflush);
	int i915_gem_object_prepare_write(struct drm_i915_gem_object *obj,
	unsigned int *needs_clflush);
	#define CLFLUSH_BEFORE BIT(0)
	#define CLFLUSH_AFTER BIT(1)
	#define CLFLUSH_FLAGS (CLFLUSH_BEFORE \| CLFLUSH_AFTER)

	static inline void
	i915_gem_object_finish_access(struct drm_i915_gem_object *obj)
	{
	i915_gem_object_unpin_pages(obj);
	i915_gem_object_unlock(obj);
	}

	static inline struct intel_engine_cs *
	i915_gem_object_last_write_engine(struct drm_i915_gem_object *obj)
	{
	struct intel_engine_cs *engine = NULL;
	struct dma_fence *fence;

	rcu_read_lock();
	fence = reservation_object_get_excl_rcu(obj->base.resv);
	rcu_read_unlock();

	if (fence && dma_fence_is_i915(fence) && !dma_fence_is_signaled(fence))
	engine = to_request(fence)->engine;
	dma_fence_put(fence);

	return engine;
	}

	void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj,
	unsigned int cache_level);
	void i915_gem_object_flush_if_display(struct drm_i915_gem_object *obj);

	int __must_check
	i915_gem_object_set_to_wc_domain(struct drm_i915_gem_object *obj, bool write);
	int __must_check
	i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write);
	int __must_check
	i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write);
	struct i915_vma * __must_check
	i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj,
	u32 alignment,
	const struct i915_ggtt_view *view,
	unsigned int flags);
	void i915_gem_object_unpin_from_display_plane(struct i915_vma *vma);

	static inline bool cpu_write_needs_clflush(struct drm_i915_gem_object *obj)
	{
	if (obj->cache_dirty)
	return false;

	if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE))
	return true;

	return obj->pin_global; /* currently in use by HW, keep flushed */
	}

	static inline void __start_cpu_write(struct drm_i915_gem_object *obj)
	{
	obj->read_domains = I915_GEM_DOMAIN_CPU;
	obj->write_domain = I915_GEM_DOMAIN_CPU;
	if (cpu_write_needs_clflush(obj))
	obj->cache_dirty = true;
	}

	int i915_gem_object_wait(struct drm_i915_gem_object *obj,
	unsigned int flags,
	long timeout);
	int i915_gem_object_wait_priority(struct drm_i915_gem_object *obj,
	unsigned int flags,
	const struct i915_sched_attr *attr);
	#define I915_PRIORITY_DISPLAY I915_USER_PRIORITY(I915_PRIORITY_MAX)

	#endif