On Fri, 4 Apr 2025 15:23:31 +0200
Thomas Zimmermann <tzimmerm...@suse.de> wrote:
> Pin and vmap are two distict operations. Do not mix them.
>
> The helper drm_client_buffer_vmap() maps the pages for fbdev-dma
> and fbdev-shmem. In both cases, the vmap operation ensures that
> the pages are available until the vunmap happens. And as the pages
> in DMA or SHMEM areas cannot be moved, there is no reason to call
> pin. Hence remove the pin call.
>
> Update drm_client_buffer_vunmap() accordingly.
>
> Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
Reviewed-by: Boris Brezillon <boris.brezil...@collabora.com>
> ---
> drivers/gpu/drm/drm_client.c | 22 +++++-----------------
> 1 file changed, 5 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
> index f1de7faf9fb45..154693066a127 100644
> --- a/drivers/gpu/drm/drm_client.c
> +++ b/drivers/gpu/drm/drm_client.c
> @@ -303,34 +303,23 @@ EXPORT_SYMBOL(drm_client_buffer_vunmap_local);
> * Returns:
> * 0 on success, or a negative errno code otherwise.
> */
> -int
> -drm_client_buffer_vmap(struct drm_client_buffer *buffer,
> - struct iosys_map *map_copy)
> +int drm_client_buffer_vmap(struct drm_client_buffer *buffer,
> + struct iosys_map *map_copy)
> {
> struct drm_gem_object *gem = buffer->gem;
> struct iosys_map *map = &buffer->map;
> int ret;
>
> drm_gem_lock(gem);
> -
> - ret = drm_gem_pin_locked(gem);
> - if (ret)
> - goto err_drm_gem_pin_locked;
> ret = drm_gem_vmap_locked(gem, map);
> - if (ret)
> - goto err_drm_gem_vmap;
> -
> drm_gem_unlock(gem);
>
> + if (ret)
> + return ret;
> +
> *map_copy = *map;
>
> return 0;
> -
> -err_drm_gem_vmap:
> - drm_gem_unpin_locked(buffer->gem);
> -err_drm_gem_pin_locked:
> - drm_gem_unlock(gem);
> - return ret;
> }
> EXPORT_SYMBOL(drm_client_buffer_vmap);
>
> @@ -349,7 +338,6 @@ void drm_client_buffer_vunmap(struct drm_client_buffer
> *buffer)
>
> drm_gem_lock(gem);
> drm_gem_vunmap_locked(gem, map);
> - drm_gem_unpin_locked(gem);
> drm_gem_unlock(gem);
> }
> EXPORT_SYMBOL(drm_client_buffer_vunmap);
