[PATCH 07/11] drm: Check locking in drm_for_each_fb

[Daniel Vetter]

Ever since framebuffers are reference counted we have a special lock
for the global fb list. Make sure users of that list do hold that
lock when using the new iterators.

Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
---
 include/drm/drm_crtc.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index a912ba06cf45..3646c47b43de 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1602,6 +1602,10 @@ static inline struct drm_property *drm_property_find(struct drm_device *dev,
 	     encoder = list_next_entry(encoder, head))
 
 #define drm_for_each_fb(fb, dev) \
-	list_for_each_entry(fb, &(dev)->mode_config.fb_list, head)
+	for (WARN_ON(!mutex_is_locked(&(dev)->mode_config.fb_lock)),		\
+	     fb = list_first_entry(&(dev)->mode_config.fb_list,	\
+					  struct drm_framebuffer, head);	\
+	     &fb->head != (&(dev)->mode_config.fb_list);			\
+	     fb = list_next_entry(fb, head))
 
 #endif /* __DRM_CRTC_H__ */
-- 
2.1.4