path: root/drivers/gpu/drm/i915/i915_gem_execbuffer.c

/*
 * Copyright © 2008,2010 Intel Corporation
 *
 * 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, sublicense,
 * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS 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:
 *    Eric Anholt <eric@anholt.net>
 *    Chris Wilson <chris@chris-wilson.co.uk>
 *
 */

#include <drm/drmP.h>
#include <drm/i915_drm.h>
#include "i915_drv.h"
#include "i915_trace.h"
#include "intel_drv.h"
#include <linux/dma_remapping.h>

struct eb_objects {
	int and;
	struct hlist_head buckets[0];
};

static struct eb_objects *
eb_create(int size)
{
	struct eb_objects *eb;
	int count = PAGE_SIZE / sizeof(struct hlist_head) / 2;
	BUILD_BUG_ON(!is_power_of_2(PAGE_SIZE / sizeof(struct hlist_head)));
	while (count > size)
		count >>= 1;
	eb = kzalloc(count*sizeof(struct hlist_head) +
		     sizeof(struct eb_objects),
		     GFP_KERNEL);
	if (eb == NULL)
		return eb;

	eb->and = count - 1;
	return eb;
}

static void
eb_reset(struct eb_objects *eb)
{
	memset(eb->buckets, 0, (eb->and+1)*sizeof(struct hlist_head));
}

static void
eb_add_object(struct eb_objects *eb, struct drm_i915_gem_object *obj)
{
	hlist_add_head(&obj->exec_node,
		       &eb->buckets[obj->exec_handle & eb->and]);
}

static struct drm_i915_gem_object *
eb_get_object(struct eb_objects *eb, unsigned long handle)
{
	struct hlist_head *head;
	struct hlist_node *node;
	struct drm_i915_gem_object *obj;

	head = &eb->buckets[handle & eb->and];
	hlist_for_each(node, head) {
		obj = hlist_entry(node, struct drm_i915_gem_object, exec_node);
		if (obj->exec_handle == handle)
			return obj;
	}

	return NULL;
}

static void
eb_destroy(struct eb_objects *eb)
{
	kfree(eb);
}

static inline int use_cpu_reloc(struct drm_i915_gem_object *obj)
{
	return (obj->base.write_domain == I915_GEM_DOMAIN_CPU ||
		!obj->map_and_fenceable ||
		obj->cache_level != I915_CACHE_NONE);
}

static int
i915_gem_execbuffer_relocate_entry(struct drm_i915_gem_object *obj,
				   struct eb_objects *eb,
				   struct drm_i915_gem_relocation_entry *reloc)
{
	struct drm_device *dev = obj->base.dev;
	struct drm_gem_object