This allows creating a GEM CMA object without an associated DMA memory buffer, and will be used to implement DRM PRIME support.
Signed-off-by: Laurent Pinchart laurent.pinchart+renesas@ideasonboard.com --- drivers/gpu/drm/drm_gem_cma_helper.c | 83 +++++++++++++++++++++--------------- 1 file changed, 48 insertions(+), 35 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c index 0a7e011..8cce330 100644 --- a/drivers/gpu/drm/drm_gem_cma_helper.c +++ b/drivers/gpu/drm/drm_gem_cma_helper.c @@ -32,62 +32,73 @@ static unsigned int get_gem_mmap_offset(struct drm_gem_object *obj) return (unsigned int)obj->map_list.hash.key << PAGE_SHIFT; }
-static void drm_gem_cma_buf_destroy(struct drm_device *drm, - struct drm_gem_cma_object *cma_obj) -{ - dma_free_writecombine(drm->dev, cma_obj->base.size, cma_obj->vaddr, - cma_obj->paddr); -} - /* - * drm_gem_cma_create - allocate an object with the given size + * __drm_gem_cma_create - Create a GEM CMA object without allocating memory + * @drm: The drm device + * @size: The GEM object size * - * returns a struct drm_gem_cma_object* on success or ERR_PTR values - * on failure. + * This function creates and initializes a GEM CMA object of the given size, but + * doesn't allocate any memory to back the object. + * + * Return 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) +static struct drm_gem_cma_object * +__drm_gem_cma_create(struct drm_device *drm, unsigned int size) { struct drm_gem_cma_object *cma_obj; struct drm_gem_object *gem_obj; int ret;
- size = round_up(size, PAGE_SIZE); - cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL); if (!cma_obj) return ERR_PTR(-ENOMEM);
- 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 err_dma_alloc; - } - gem_obj = &cma_obj->base;
ret = drm_gem_object_init(drm, gem_obj, size); if (ret) - goto err_obj_init; + goto error;
ret = drm_gem_create_mmap_offset(gem_obj); - if (ret) - goto err_create_mmap_offset; + if (ret) { + drm_gem_object_release(gem_obj); + goto error; + }
return cma_obj;
-err_create_mmap_offset: - drm_gem_object_release(gem_obj); +error: + kfree(cma_obj); + return ERR_PTR(ret); +}
-err_obj_init: - drm_gem_cma_buf_destroy(drm, cma_obj); +/* + * 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;
-err_dma_alloc: - kfree(cma_obj); + size = round_up(size, PAGE_SIZE);
- return ERR_PTR(ret); + 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); + drm_gem_cma_free_object(&cma_obj->base); + return ERR_PTR(-ENOMEM); + } + + return cma_obj; } EXPORT_SYMBOL_GPL(drm_gem_cma_create);
@@ -143,11 +154,13 @@ void drm_gem_cma_free_object(struct drm_gem_object *gem_obj) if (gem_obj->map_list.map) drm_gem_free_mmap_offset(gem_obj);
- drm_gem_object_release(gem_obj); - cma_obj = to_drm_gem_cma_obj(gem_obj);
- drm_gem_cma_buf_destroy(gem_obj->dev, cma_obj); + if (cma_obj->vaddr) + dma_free_writecombine(gem_obj->dev->dev, cma_obj->base.size, + cma_obj->vaddr, cma_obj->paddr); + + drm_gem_object_release(gem_obj);
kfree(cma_obj); }