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>
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 5b2cbb7..bfce099 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -194,7 +194,6 @@
* @type: object type
*
* LOCKING:
- * Caller must hold DRM mode_config lock.
*
* Create a unique identifier based on @ptr in @dev's identifier space. Used
* for tracking modes, CRTCs and connectors.
@@ -209,15 +208,15 @@
int new_id = 0;
int ret;
- WARN(!mutex_is_locked(&dev->mode_config.mutex),
- "%s called w/o mode_config lock\n", __func__);
again:
if (idr_pre_get(&dev->mode_config.crtc_idr, GFP_KERNEL) == 0) {
DRM_ERROR("Ran out memory getting a mode number\n");
return -EINVAL;
}
+ mutex_lock(&dev->mode_config.idr_mutex);
ret = idr_get_new_above(&dev->mode_config.crtc_idr, obj, 1, &new_id);
+ mutex_unlock(&dev->mode_config.idr_mutex);
if (ret == -EAGAIN)
goto again;
@@ -239,16 +238,20 @@
static void drm_mode_object_put(struct drm_device *dev,
struct drm_mode_object *object)
{
+ mutex_lock(&dev->mode_config.idr_mutex);
idr_remove(&dev->mode_config.crtc_idr, object->id);
+ mutex_unlock(&dev->mode_config.idr_mutex);
}
void *drm_mode_object_find(struct drm_device *dev, uint32_t id, uint32_t type)
{
- struct drm_mode_object *obj;
+ struct drm_mode_object *obj = NULL;
+ mutex_lock(&dev->mode_config.idr_mutex);
obj = idr_find(&dev->mode_config.crtc_idr, id);
if (!obj || (obj->type != type) || (obj->id != id))
- return NULL;
+ obj = NULL;
+ mutex_unlock(&dev->mode_config.idr_mutex);
return obj;
}
@@ -786,6 +789,7 @@
void drm_mode_config_init(struct drm_device *dev)
{
mutex_init(&dev->mode_config.mutex);
+ mutex_init(&dev->mode_config.idr_mutex);
INIT_LIST_HEAD(&dev->mode_config.fb_list);
INIT_LIST_HEAD(&dev->mode_config.fb_kernel_list);
INIT_LIST_HEAD(&dev->mode_config.crtc_list);