drm/gem: Inline drm_gem_pin() into PRIME helpers

Inline drm_gem_pin() into its only caller drm_gem_map_attach()
and update the documentation in the callback's purpose. Do the
equivalent for drm_gem_unpin(). Also add stricter error checking
on the involved locking.

The pin operation in the GEM object functions is a helper for
PRIME-exported buffer objects. Having drm_gem_pin() gives the
impression of a general-purpose interface, which is not the case.
Removing it makes the pin callback a bit harder to misuse.

v2:
- clarify comment on pin callback (Dmitry)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://lore.kernel.org/r/20250526132634.531789-5-tzimmermann@suse.de

1 files changed, 0 insertions, 32 deletions

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 1e659d2660f7..a0a3b6baa569 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -1184,38 +1184,6 @@ void drm_gem_print_info(struct drm_printer *p, unsigned int indent,
 		obj->funcs->print_info(p, indent, obj);
 }
 
-int drm_gem_pin_locked(struct drm_gem_object *obj)
-{
-	if (obj->funcs->pin)
-		return obj->funcs->pin(obj);
-
-	return 0;
-}
-
-void drm_gem_unpin_locked(struct drm_gem_object *obj)
-{
-	if (obj->funcs->unpin)
-		obj->funcs->unpin(obj);
-}
-
-int drm_gem_pin(struct drm_gem_object *obj)
-{
-	int ret;
-
-	dma_resv_lock(obj->resv, NULL);
-	ret = drm_gem_pin_locked(obj);
-	dma_resv_unlock(obj->resv);
-
-	return ret;
-}
-
-void drm_gem_unpin(struct drm_gem_object *obj)
-{
-	dma_resv_lock(obj->resv, NULL);
-	drm_gem_unpin_locked(obj);
-	dma_resv_unlock(obj->resv);
-}
-
 int drm_gem_vmap_locked(struct drm_gem_object *obj, struct iosys_map *map)
 {
 	int ret;