/**
* drm_gem_cma_create - allocate an object with the given size
* @drm: DRM device
* @size: size of the object to allocate
*
* This function creates a CMA GEM object and allocates a contiguous chunk of
* memory as backing store. The backing memory has the writecombine attribute
* set.
*
* Returns:
* A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
* error code on failure.
*/
struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,
size_t size)
{
struct drm_gem_cma_object *cma_obj;
int ret;
size = round_up(size, PAGE_SIZE);
cma_obj = __drm_gem_cma_create(drm, size);
if (IS_ERR(cma_obj))
return cma_obj;
cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
&cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
if (!cma_obj->vaddr) {
dev_err(drm->dev, "failed to allocate buffer with size %zu\n",
size);
ret = -ENOMEM;
goto error;
}
return cma_obj;
error:
drm->driver->gem_free_object(&cma_obj->base);
return ERR_PTR(ret);
}
/*
* drm_gem_cma_create - allocate an object with the given size
*
* returns a struct drm_gem_cma_object* on success or ERR_PTR values
* on failure.
*/
struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,
unsigned int size)
{
struct drm_gem_cma_object *cma_obj;
struct sg_table *sgt = NULL;
int ret;
size = round_up(size, PAGE_SIZE);
cma_obj = __drm_gem_cma_create(drm, size);
if (IS_ERR(cma_obj))
return cma_obj;
cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
&cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
if (!cma_obj->vaddr) {
dev_err(drm->dev, "failed to allocate buffer with size %d\n",
size);
ret = -ENOMEM;
goto error;
}
sgt = kzalloc(sizeof(*cma_obj->sgt), GFP_KERNEL);
if (sgt == NULL) {
ret = -ENOMEM;
goto error;
}
ret = dma_get_sgtable(drm->dev, sgt, cma_obj->vaddr,
cma_obj->paddr, size);
if (ret < 0)
goto error;
cma_obj->sgt = sgt;
return cma_obj;
error:
kfree(sgt);
drm_gem_cma_free_object(&cma_obj->base);
return ERR_PTR(ret);
}
struct drm_gem_object *
drm_gem_cma_prime_import_sg_table(struct drm_device *dev, size_t size,
struct sg_table *sgt)
{
struct drm_gem_cma_object *cma_obj;
if (sgt->nents != 1)
return ERR_PTR(-EINVAL);
/* Create a CMA GEM buffer. */
cma_obj = __drm_gem_cma_create(dev, size);
if (IS_ERR(cma_obj))
return ERR_PTR(PTR_ERR(cma_obj));
cma_obj->paddr = sg_dma_address(sgt->sgl);
cma_obj->sgt = sgt;
DRM_DEBUG_PRIME("dma_addr = 0x%x, size = %zu\n", cma_obj->paddr, size);
return &cma_obj->base;
}
/**
* drm_gem_cma_prime_import_sg_table - produce a CMA GEM object from another
* driver's scatter/gather table of pinned pages
* @dev: device to import into
* @attach: DMA-BUF attachment
* @sgt: scatter/gather table of pinned pages
*
* This function imports a scatter/gather table exported via DMA-BUF by
* another driver. Imported buffers must be physically contiguous in memory
* (i.e. the scatter/gather table must contain a single entry). Drivers that
* use the CMA helpers should set this as their DRM driver's
* ->gem_prime_import_sg_table() callback.
*
* Returns:
* A pointer to a newly created GEM object or an ERR_PTR-encoded negative
* error code on failure.
*/
struct drm_gem_object *
drm_gem_cma_prime_import_sg_table(struct drm_device *dev,
struct dma_buf_attachment *attach,
struct sg_table *sgt)
{
struct drm_gem_cma_object *cma_obj;
if (sgt->nents != 1)
return ERR_PTR(-EINVAL);
/* Create a CMA GEM buffer. */
cma_obj = __drm_gem_cma_create(dev, attach->dmabuf->size);
if (IS_ERR(cma_obj))
return ERR_CAST(cma_obj);
cma_obj->paddr = sg_dma_address(sgt->sgl);
cma_obj->sgt = sgt;
DRM_DEBUG_PRIME("dma_addr = %pad, size = %zu\n", &cma_obj->paddr, attach->dmabuf->size);
return &cma_obj->base;
}
