drm: create mode_config idr lock

Create a separate mode_config IDR lock for simplicity.  The core DRM
config structures (connector, mode, etc. lists) are still protected by
the mode_config mutex, but the CRTC IDR (used for the various identifier
IDs) is now protected by the mode_config idr_mutex.  Simplifies the
locking a bit and removes a warning.

All objects are protected by the config mutex, we may in the future,
split the object further to have reference counts.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 47809ac94bc..d54de24bf37 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -528,7 +528,8 @@ struct drm_mode_group {
  *
  */
 struct drm_mode_config {
-	struct mutex mutex; /* protects configuration and IDR */
+	struct mutex mutex; /* protects configuration (mode lists etc.) */
+	struct mutex idr_mutex; /* for IDR management */
 	struct idr crtc_idr; /* use this idr for all IDs, fb, crtc, connector, modes - just makes life easier */
 	/* this is limited to one for now */
 	int num_fb;