[PATCH v3 3/5] drm/gem: Clear mapping addresses for unused framebuffer planes

[Thomas Zimmermann]

Set the returned mapping address to NULL if a framebuffer plane does
not have a BO associated with it. Likewise, ignore mappings of NULL
during framebuffer unmap operations. Allows users of the functions to
perform unmap operations of certain BOs by themselfes.

Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
Reviewed-by: Sam Ravnborg <s...@ravnborg.org>
---
 drivers/gpu/drm/drm_gem_framebuffer_helper.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c 
b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index 243affbad437..02928607a716 100644
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -336,8 +336,10 @@ int drm_gem_fb_vmap(struct drm_framebuffer *fb,
 
        for (i = 0; i < DRM_FORMAT_MAX_PLANES; ++i) {
                obj = drm_gem_fb_get_obj(fb, i);
-               if (!obj)
+               if (!obj) {
+                       dma_buf_map_clear(&map[i]);
                        continue;
+               }
                ret = drm_gem_vmap(obj, &map[i]);
                if (ret)
                        goto err_drm_gem_vunmap;
@@ -377,6 +379,8 @@ void drm_gem_fb_vunmap(struct drm_framebuffer *fb,
                obj = drm_gem_fb_get_obj(fb, i);
                if (!obj)
                        continue;
+               if (dma_buf_map_is_null(&map[i]))
+                       continue;
                drm_gem_vunmap(obj, &map[i]);
        }
 }
-- 
2.32.0