Commit 0d938863 authored by Thomas Hellström's avatar Thomas Hellström
Browse files

drm/i915/ttm: Implement a function to copy the contents of two TTM-based objects 



When backing up or restoring contents of pinned objects at suspend /
resume time we need to allocate a new object as the backup. Add a function
to facilitate copies between the two. Some data needs to be copied before
the migration context is ready for operation, so make sure we can
disable accelerated copies.

v2:
- Fix a missing return value check (Matthew Auld)

Signed-off-by: default avatarThomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: default avatarMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210922062527.865433-2-thomas.hellstrom@linux.intel.com
parent 2dfa597d

drivers/gpu/drm/i915/gem/i915_gem_ttm.c

+60 −9
Original line number Diff line number Diff line
@@ -429,6 +429,7 @@ i915_ttm_resource_get_st(struct drm_i915_gem_object *obj, 
static int i915_ttm_accel_move(struct ttm_buffer_object *bo,

			       bool clear,

			       struct ttm_resource *dst_mem,

			       struct ttm_tt *dst_ttm,

			       struct sg_table *dst_st)

{

	struct drm_i915_private *i915 = container_of(bo->bdev, typeof(*i915),
@@ -438,14 +439,14 @@ static int i915_ttm_accel_move(struct ttm_buffer_object *bo, 
	struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);

	struct sg_table *src_st;

	struct i915_request *rq;

	struct ttm_tt *ttm = bo->ttm;

	struct ttm_tt *src_ttm = bo->ttm;

	enum i915_cache_level src_level, dst_level;

	int ret;



	if (!i915->gt.migrate.context)

		return -EINVAL;



	dst_level = i915_ttm_cache_level(i915, dst_mem, ttm);

	dst_level = i915_ttm_cache_level(i915, dst_mem, dst_ttm);

	if (clear) {

		if (bo->type == ttm_bo_type_kernel)

			return -EINVAL;
@@ -462,10 +463,10 @@ static int i915_ttm_accel_move(struct ttm_buffer_object *bo, 
		}

		intel_engine_pm_put(i915->gt.migrate.context->engine);

	} else {

		src_st = src_man->use_tt ? i915_ttm_tt_get_st(ttm) :

		src_st = src_man->use_tt ? i915_ttm_tt_get_st(src_ttm) :

			obj->ttm.cached_io_st;



		src_level = i915_ttm_cache_level(i915, bo->resource, ttm);

		src_level = i915_ttm_cache_level(i915, bo->resource, src_ttm);

		intel_engine_pm_get(i915->gt.migrate.context->engine);

		ret = intel_context_migrate_copy(i915->gt.migrate.context,

						 NULL, src_st->sgl, src_level,
@@ -485,11 +486,14 @@ static int i915_ttm_accel_move(struct ttm_buffer_object *bo, 


static void __i915_ttm_move(struct ttm_buffer_object *bo, bool clear,

			    struct ttm_resource *dst_mem,

			    struct sg_table *dst_st)

			    struct ttm_tt *dst_ttm,

			    struct sg_table *dst_st,

			    bool allow_accel)

{

	int ret;

	int ret = -EINVAL;



	ret = i915_ttm_accel_move(bo, clear, dst_mem, dst_st);

	if (allow_accel)

		ret = i915_ttm_accel_move(bo, clear, dst_mem, dst_ttm, dst_st);

	if (ret) {

		struct drm_i915_gem_object *obj = i915_ttm_to_gem(bo);

		struct intel_memory_region *dst_reg, *src_reg;
@@ -504,7 +508,7 @@ static void __i915_ttm_move(struct ttm_buffer_object *bo, bool clear, 
		GEM_BUG_ON(!dst_reg || !src_reg);



		dst_iter = !cpu_maps_iomem(dst_mem) ?

			ttm_kmap_iter_tt_init(&_dst_iter.tt, bo->ttm) :

			ttm_kmap_iter_tt_init(&_dst_iter.tt, dst_ttm) :

			ttm_kmap_iter_iomap_init(&_dst_iter.io, &dst_reg->iomap,

						 dst_st, dst_reg->region.start);
@@ -559,7 +563,7 @@ static int i915_ttm_move(struct ttm_buffer_object *bo, bool evict, 


	clear = !cpu_maps_iomem(bo->resource) && (!ttm || !ttm_tt_is_populated(ttm));

	if (!(clear && ttm && !(ttm->page_flags & TTM_PAGE_FLAG_ZERO_ALLOC)))

		__i915_ttm_move(bo, clear, dst_mem, dst_st);

		__i915_ttm_move(bo, clear, dst_mem, bo->ttm, dst_st, true);



	ttm_bo_move_sync_cleanup(bo, dst_mem);

	i915_ttm_adjust_domains_after_move(obj);
@@ -974,3 +978,50 @@ i915_gem_ttm_system_setup(struct drm_i915_private *i915, 
	intel_memory_region_set_name(mr, "system-ttm");

	return mr;

}



/**

 * i915_gem_obj_copy_ttm - Copy the contents of one ttm-based gem object to

 * another

 * @dst: The destination object

 * @src: The source object

 * @allow_accel: Allow using the blitter. Otherwise TTM memcpy is used.

 * @intr: Whether to perform waits interruptible:

 *

 * Note: The caller is responsible for assuring that the underlying

 * TTM objects are populated if needed and locked.

 *

 * Return: Zero on success. Negative error code on error. If @intr == true,

 * then it may return -ERESTARTSYS or -EINTR.

 */

int i915_gem_obj_copy_ttm(struct drm_i915_gem_object *dst,

			  struct drm_i915_gem_object *src,

			  bool allow_accel, bool intr)

{

	struct ttm_buffer_object *dst_bo = i915_gem_to_ttm(dst);

	struct ttm_buffer_object *src_bo = i915_gem_to_ttm(src);

	struct ttm_operation_ctx ctx = {

		.interruptible = intr,

	};

	struct sg_table *dst_st;

	int ret;



	assert_object_held(dst);

	assert_object_held(src);



	/*

	 * Sync for now. This will change with async moves.

	 */

	ret = ttm_bo_wait_ctx(dst_bo, &ctx);

	if (!ret)

		ret = ttm_bo_wait_ctx(src_bo, &ctx);

	if (ret)

		return ret;



	dst_st = gpu_binds_iomem(dst_bo->resource) ?

		dst->ttm.cached_io_st : i915_ttm_tt_get_st(dst_bo->ttm);



	__i915_ttm_move(src_bo, false, dst_bo->resource, dst_bo->ttm,

			dst_st, allow_accel);



	return 0;

}

drivers/gpu/drm/i915/gem/i915_gem_ttm.h

+4 −0
Original line number Diff line number Diff line
@@ -46,4 +46,8 @@ int __i915_gem_ttm_object_init(struct intel_memory_region *mem, 
			       resource_size_t size,

			       resource_size_t page_size,

			       unsigned int flags);



int i915_gem_obj_copy_ttm(struct drm_i915_gem_object *dst,

			  struct drm_i915_gem_object *src,

			  bool allow_accel, bool intr);

#endif