linux/drivers/gpu/drm/i915/i915_scatterlist.c

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

#include "i915_scatterlist.h"
#include "i915_ttm_buddy_manager.h"

#include <drm/drm_buddy.h>
#include <drm/drm_mm.h>

#include <linux/slab.h>

bool i915_sg_trim(struct sg_table *orig_st)
{ … }

static void i915_refct_sgt_release(struct kref *ref)
{ … }

static const struct i915_refct_sgt_ops rsgt_ops = …;

/**
 * i915_refct_sgt_init - Initialize a struct i915_refct_sgt with default ops
 * @rsgt: The struct i915_refct_sgt to initialize.
 * @size: The size of the underlying memory buffer.
 */
void i915_refct_sgt_init(struct i915_refct_sgt *rsgt, size_t size)
{ … }

/**
 * i915_rsgt_from_mm_node - Create a refcounted sg_table from a struct
 * drm_mm_node
 * @node: The drm_mm_node.
 * @region_start: An offset to add to the dma addresses of the sg list.
 * @page_alignment: Required page alignment for each sg entry. Power of two.
 *
 * Create a struct sg_table, initializing it from a struct drm_mm_node,
 * taking a maximum segment length into account, splitting into segments
 * if necessary.
 *
 * Return: A pointer to a kmalloced struct i915_refct_sgt on success, negative
 * error code cast to an error pointer on failure.
 */
struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node,
					      u64 region_start,
					      u32 page_alignment)
{ … }

/**
 * i915_rsgt_from_buddy_resource - Create a refcounted sg_table from a struct
 * i915_buddy_block list
 * @res: The struct i915_ttm_buddy_resource.
 * @region_start: An offset to add to the dma addresses of the sg list.
 * @page_alignment: Required page alignment for each sg entry. Power of two.
 *
 * Create a struct sg_table, initializing it from struct i915_buddy_block list,
 * taking a maximum segment length into account, splitting into segments
 * if necessary.
 *
 * Return: A pointer to a kmalloced struct i915_refct_sgts on success, negative
 * error code cast to an error pointer on failure.
 */
struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res,
						     u64 region_start,
						     u32 page_alignment)
{ … }

#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
#include "selftests/scatterlist.c"
#endif