linux-zen-server/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c

154 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2011 Texas Instruments Incorporated - https://www.ti.com/
* Author: Rob Clark <rob.clark@linaro.org>
*/
#include <linux/dma-buf.h>
#include <linux/highmem.h>
#include <drm/drm_prime.h>
#include "omap_drv.h"
MODULE_IMPORT_NS(DMA_BUF);
/* -----------------------------------------------------------------------------
* DMABUF Export
*/
static struct sg_table *omap_gem_map_dma_buf(
struct dma_buf_attachment *attachment,
enum dma_data_direction dir)
{
struct drm_gem_object *obj = attachment->dmabuf->priv;
struct sg_table *sg;
sg = omap_gem_get_sg(obj, dir);
if (IS_ERR(sg))
return sg;
return sg;
}
static void omap_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
struct sg_table *sg, enum dma_data_direction dir)
{
struct drm_gem_object *obj = attachment->dmabuf->priv;
omap_gem_put_sg(obj, sg);
}
static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer,
enum dma_data_direction dir)
{
struct drm_gem_object *obj = buffer->priv;
struct page **pages;
if (omap_gem_flags(obj) & OMAP_BO_TILED_MASK) {
/* TODO we would need to pin at least part of the buffer to
* get de-tiled view. For now just reject it.
*/
return -ENOMEM;
}
/* make sure we have the pages: */
return omap_gem_get_pages(obj, &pages, true);
}
static int omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer,
enum dma_data_direction dir)
{
struct drm_gem_object *obj = buffer->priv;
omap_gem_put_pages(obj);
return 0;
}
static int omap_gem_dmabuf_mmap(struct dma_buf *buffer,
struct vm_area_struct *vma)
{
struct drm_gem_object *obj = buffer->priv;
int ret = 0;
dma_resv_assert_held(buffer->resv);
ret = drm_gem_mmap_obj(obj, omap_gem_mmap_size(obj), vma);
if (ret < 0)
return ret;
return omap_gem_mmap_obj(obj, vma);
}
static const struct dma_buf_ops omap_dmabuf_ops = {
.map_dma_buf = omap_gem_map_dma_buf,
.unmap_dma_buf = omap_gem_unmap_dma_buf,
.release = drm_gem_dmabuf_release,
.begin_cpu_access = omap_gem_dmabuf_begin_cpu_access,
.end_cpu_access = omap_gem_dmabuf_end_cpu_access,
.mmap = omap_gem_dmabuf_mmap,
};
struct dma_buf *omap_gem_prime_export(struct drm_gem_object *obj, int flags)
{
DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
exp_info.ops = &omap_dmabuf_ops;
exp_info.size = omap_gem_mmap_size(obj);
exp_info.flags = flags;
exp_info.priv = obj;
exp_info.resv = obj->resv;
return drm_gem_dmabuf_export(obj->dev, &exp_info);
}
/* -----------------------------------------------------------------------------
* DMABUF Import
*/
struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev,
struct dma_buf *dma_buf)
{
struct dma_buf_attachment *attach;
struct drm_gem_object *obj;
struct sg_table *sgt;
int ret;
if (dma_buf->ops == &omap_dmabuf_ops) {
obj = dma_buf->priv;
if (obj->dev == dev) {
/*
* Importing dmabuf exported from out own gem increases
* refcount on gem itself instead of f_count of dmabuf.
*/
drm_gem_object_get(obj);
return obj;
}
}
attach = dma_buf_attach(dma_buf, dev->dev);
if (IS_ERR(attach))
return ERR_CAST(attach);
get_dma_buf(dma_buf);
sgt = dma_buf_map_attachment_unlocked(attach, DMA_TO_DEVICE);
if (IS_ERR(sgt)) {
ret = PTR_ERR(sgt);
goto fail_detach;
}
obj = omap_gem_new_dmabuf(dev, dma_buf->size, sgt);
if (IS_ERR(obj)) {
ret = PTR_ERR(obj);
goto fail_unmap;
}
obj->import_attach = attach;
return obj;
fail_unmap:
dma_buf_unmap_attachment_unlocked(attach, sgt, DMA_TO_DEVICE);
fail_detach:
dma_buf_detach(dma_buf, attach);
dma_buf_put(dma_buf);
return ERR_PTR(ret);
}