Commit 5462dc83 authored by Dmitry Osipenko's avatar Dmitry Osipenko
Browse files

drm/gem: Document locking rule of vmap and evict callbacks 



The vmap/vunmap/evict GEM callbacks are always invoked with a held GEM's
reservation lock. Document this locking rule for clarity.

Reviewed-by: default avatarBoris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Acked-by: default avatarThomas Zimmermann <tzimmermann@suse.d>
Signed-off-by: default avatarDmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250322212608.40511-4-dmitry.osipenko@collabora.com
parent 9a0fd089

include/drm/drm_gem.h

+6 −3
Original line number Diff line number Diff line
@@ -159,7 +159,8 @@ struct drm_gem_object_funcs { 
	 * @vmap:

	 *

	 * Returns a virtual address for the buffer. Used by the

	 * drm_gem_dmabuf_vmap() helper.

	 * drm_gem_dmabuf_vmap() helper. Called with a held GEM reservation

	 * lock.

	 *

	 * This callback is optional.

	 */
@@ -169,7 +170,8 @@ struct drm_gem_object_funcs { 
	 * @vunmap:

	 *

	 * Releases the address previously returned by @vmap. Used by the

	 * drm_gem_dmabuf_vunmap() helper.

	 * drm_gem_dmabuf_vunmap() helper. Called with a held GEM reservation

	 * lock.

	 *

	 * This callback is optional.

	 */
@@ -192,7 +194,8 @@ struct drm_gem_object_funcs { 
	 * @evict:

	 *

	 * Evicts gem object out from memory. Used by the drm_gem_object_evict()

	 * helper. Returns 0 on success, -errno otherwise.

	 * helper. Returns 0 on success, -errno otherwise. Called with a held

	 * GEM reservation lock.

	 *

	 * This callback is optional.

	 */