2 files changed, 74 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);
 
diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index 421e029a6b3e..2bc0605c8bca 100644
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -15,6 +15,8 @@
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_modeset_helper.h>
 
+#include "drm_internal.h"
+
 #define AFBC_HEADER_SIZE		16
 #define AFBC_TH_LAYOUT_ALIGNMENT	8
 #define AFBC_HDR_ALIGN			64
@@ -310,6 +312,76 @@ drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file,
 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty);
 
 /**
+ * drm_gem_fb_vmap - maps all framebuffer BOs into kernel address space
+ * @fb: the framebuffer
+ * @map: returns the mapping's address for each BO
+ *
+ * This function maps all buffer objects of the given framebuffer into
+ * kernel address space and stores them in struct dma_buf_map. If the
+ * mapping operation fails for one of the BOs, the function unmaps the
+ * already established mappings automatically.
+ *
+ * See drm_gem_fb_vunmap() for unmapping.
+ *
+ * Returns:
+ * 0 on success, or a negative errno code otherwise.
+ */
+int drm_gem_fb_vmap(struct drm_framebuffer *fb,
+		    struct dma_buf_map map[static DRM_FORMAT_MAX_PLANES])
+{
+	struct drm_gem_object *obj;
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < DRM_FORMAT_MAX_PLANES; ++i) {
+		obj = drm_gem_fb_get_obj(fb, i);
+		if (!obj)
+			continue;
+		ret = drm_gem_vmap(obj, &map[i]);
+		if (ret)
+			goto err_drm_gem_vunmap;
+	}
+
+	return 0;
+
+err_drm_gem_vunmap:
+	while (i) {
+		--i;
+		obj = drm_gem_fb_get_obj(fb, i);
+		if (!obj)
+			continue;
+		drm_gem_vunmap(obj, &map[i]);
+	}
+	return ret;
+}
+EXPORT_SYMBOL(drm_gem_fb_vmap);
+
+/**
+ * drm_gem_fb_vunmap - unmaps framebuffer BOs from kernel address space
+ * @fb: the framebuffer
+ * @map: mapping addresses as returned by drm_gem_fb_vmap()
+ *
+ * This function unmaps all buffer objects of the given framebuffer.
+ *
+ * See drm_gem_fb_vmap() for more information.
+ */
+void drm_gem_fb_vunmap(struct drm_framebuffer *fb,
+		       struct dma_buf_map map[static DRM_FORMAT_MAX_PLANES])
+{
+	unsigned int i = DRM_FORMAT_MAX_PLANES;
+	struct drm_gem_object *obj;
+
+	while (i) {
+		--i;
+		obj = drm_gem_fb_get_obj(fb, i);
+		if (!obj)
+			continue;
+		drm_gem_vunmap(obj, &map[i]);
+	}
+}
+EXPORT_SYMBOL(drm_gem_fb_vunmap);
+
+/**
  * drm_gem_fb_begin_cpu_access - prepares GEM buffer objects for CPU access
  * @fb: the framebuffer
  * @dir: access mode