1. 根目录:
2. drivers
3. gpu
4. drm
5. radeon
6. radeon_prime.c

/*
 * Copyright 2012 Advanced Micro Devices, Inc.
 *
 * 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
 *
 * based on nouveau_prime.c
 *
 * Authors: Alex Deucher
 */
#include <drm/drmP.h>

#include "radeon.h"
#include <drm/radeon_drm.h>
#include <linux/dma-buf.h>

struct sg_table *radeon_gem_prime_get_sg_table(struct drm_gem_object *obj)
{
	struct radeon_bo *bo = gem_to_radeon_bo(obj);
	int npages = bo->tbo.num_pages;

	return drm_prime_pages_to_sg(bo->tbo.ttm->pages, npages);
}

void *radeon_gem_prime_vmap(struct drm_gem_object *obj)
{
	struct radeon_bo *bo = gem_to_radeon_bo(obj);
	int ret;

	ret = ttm_bo_kmap(&bo->tbo, 0, bo->tbo.num_pages,
			  &bo->dma_buf_vmap);
	if (ret)
		return ERR_PTR(ret);

	return bo->dma_buf_vmap.virtual;
}

void radeon_gem_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
{
	struct radeon_bo *bo = gem_to_radeon_bo(obj);

	ttm_bo_kunmap(&bo->dma_buf_vmap);
}

struct drm_gem_object *radeon_gem_prime_import_sg_table(struct drm_device *dev,
							struct dma_buf_attachment *attach,
							struct sg_table *sg)
{
	struct reservation_object *resv = attach->dmabuf->resv;
	struct radeon_device *rdev = dev->dev_private;
	struct radeon_bo *bo;
	int ret;

	ww_mutex_lock(&resv->lock, NULL);
	ret = radeon_bo_create(rdev, attach->dmabuf->size, PAGE_SIZE, false,
			       RADEON_GEM_DOMAIN_GTT, 0, sg, resv, &bo);
	ww_mutex_unlock(&resv->lock);
	if (ret)
		return ERR_PTR(ret);

	mutex_lock(&rdev->gem.mutex);
	list_add_tail(&bo->list, &rdev->gem.objects);
	mutex_unlock(&rdev->gem.mutex);

	return &bo->gem_base;
}

int radeon_gem_prime_pin(struct drm_gem_object *obj)
{
	struct radeon_bo *bo = gem_to_radeon_bo(obj);
	int ret = 0;

	ret = radeon_bo_reserve(bo, false);
	if (unlikely(ret != 0))
		return ret;

	/* pin buffer into GTT */
	ret = radeon_bo_pin(bo, RADEON_GEM_DOMAIN_GTT, NULL);
	radeon_bo_unreserve(bo);
	return ret;
}

void radeon_gem_prime_unpin(struct drm_gem_object *obj)
{
	struct radeon_bo *bo = gem_to_radeon_bo(obj);
	int ret = 0;

	ret = radeon_bo_reserve(bo, false);
	if (unlikely(ret != 0))
		return;

	radeon_bo_unpin(bo);
	radeon_bo_unreserve(bo);
}


struct reservation_object *radeon_gem_prime_res_obj(struct drm_gem_object *obj)
{
	struct radeon_bo *bo = gem_to_radeon_bo(obj);

	return bo->tbo.resv;
}

struct dma_buf *radeon_gem_prime_export(struct drm_device *dev,
					struct drm_gem_object *gobj,
					int flags)
{
	struct radeon_bo *bo = gem_to_radeon_bo(gobj);
	if (radeon_ttm_tt_has_userptr(bo->tbo.ttm))
		return ERR_PTR(-EPERM);
	return drm_gem_prime_export(dev, gobj, flags);
}