drm/gem: Provide drm_gem_fb_{vmap,vunmap}()

Move framebuffer vmap code from shadow-buffered plane state into the new
interfaces drm_gem_fb_vmap() and drm_gem_fb_vunmap(). These functions
provide mappings of a framebuffer's BOs into kernel address space. No
functional changes.

v4:
	* remove duplicated blank line
v2:
	* using [static N] for array parameters enables compile-time checks
	* include <drm/drm_fourcc.h> for DRM_FORMAT_MAX_PLANES (kernel
	  test robot)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210730183511.20080-3-tzimmermann@suse.de

1 files changed, 2 insertions, 33 deletions

diff --git a/drivers/gpu/drm/drm_gem_atomic_helper.c b/drivers/gpu/drm/drm_gem_atomic_helper.c
index 86b3c676e0b1..4865870cc60e 100644
--- a/drivers/gpu/drm/drm_gem_atomic_helper.c
+++ b/drivers/gpu/drm/drm_gem_atomic_helper.c
@@ -330,10 +330,7 @@ int drm_gem_prepare_shadow_fb(struct drm_plane *plane, struct drm_plane_state *p
 {
 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
 	struct drm_framebuffer *fb = plane_state->fb;
-	struct drm_gem_object *obj;
-	struct dma_buf_map map;
 	int ret;
-	size_t i;
 
 	if (!fb)
 		return 0;
@@ -342,27 +339,7 @@ int drm_gem_prepare_shadow_fb(struct drm_plane *plane, struct drm_plane_state *p
 	if (ret)
 		return ret;
 
-	for (i = 0; i < ARRAY_SIZE(shadow_plane_state->map); ++i) {
-		obj = drm_gem_fb_get_obj(fb, i);
-		if (!obj)
-			continue;
-		ret = drm_gem_vmap(obj, &map);
-		if (ret)
-			goto err_drm_gem_vunmap;
-		shadow_plane_state->map[i] = map;
-	}
-
-	return 0;
-
-err_drm_gem_vunmap:
-	while (i) {
-		--i;
-		obj = drm_gem_fb_get_obj(fb, i);
-		if (!obj)
-			continue;
-		drm_gem_vunmap(obj, &shadow_plane_state->map[i]);
-	}
-	return ret;
+	return drm_gem_fb_vmap(fb, shadow_plane_state->map);
 }
 EXPORT_SYMBOL(drm_gem_prepare_shadow_fb);
 
@@ -380,19 +357,11 @@ void drm_gem_cleanup_shadow_fb(struct drm_plane *plane, struct drm_plane_state *
 {
 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
 	struct drm_framebuffer *fb = plane_state->fb;
-	size_t i = ARRAY_SIZE(shadow_plane_state->map);
-	struct drm_gem_object *obj;
 
 	if (!fb)
 		return;
 
-	while (i) {
-		--i;
-		obj = drm_gem_fb_get_obj(fb, i);
-		if (!obj)
-			continue;
-		drm_gem_vunmap(obj, &shadow_plane_state->map[i]);
-	}
+	drm_gem_fb_vunmap(fb, shadow_plane_state->map);
 }
 EXPORT_SYMBOL(drm_gem_cleanup_shadow_fb);