I want to wrap the creation of a dma-buf from a gem object in it, so that the obj->export_dma_buf cache can be atomically filled in.
Instead of creating a new mutex just for that variable I've figured I can reuse the existing dev->object_name_lock, especially since the new semantics will exactly mirror the flink obj->name already protected by that lock.
v2: idr_preload/idr_preload_end is now an atomic section, so need to move the mutex locking outside.
Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch --- drivers/gpu/drm/drm_gem.c | 18 +++++++++--------- include/drm/drmP.h | 2 +- 2 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 1609a3d..2bcffb9 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -92,7 +92,7 @@ drm_gem_init(struct drm_device *dev) { struct drm_gem_mm *mm;
- spin_lock_init(&dev->object_name_lock); + mutex_init(&dev->object_name_lock); idr_init(&dev->object_name_idr);
mm = kzalloc(sizeof(struct drm_gem_mm), GFP_KERNEL); @@ -252,10 +252,10 @@ drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) * checked for a name */
- spin_lock(&obj->dev->object_name_lock); + mutex_lock(&obj->dev->object_name_lock); if (--obj->handle_count == 0) drm_gem_object_handle_free(obj); - spin_unlock(&obj->dev->object_name_lock); + mutex_unlock(&obj->dev->object_name_lock);
drm_gem_object_unreference_unlocked(obj); } @@ -333,16 +333,16 @@ drm_gem_handle_create(struct drm_file *file_priv, * Get the user-visible handle using idr. Preload and perform * allocation under our spinlock. */ + mutex_lock(&dev->object_name_lock); idr_preload(GFP_KERNEL); - spin_lock(&dev->object_name_lock); spin_lock(&file_priv->table_lock);
ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT); drm_gem_object_reference(obj); obj->handle_count++; spin_unlock(&file_priv->table_lock); - spin_unlock(&dev->object_name_lock); idr_preload_end(); + mutex_unlock(&dev->object_name_lock); if (ret < 0) { drm_gem_object_handle_unreference_unlocked(obj); return ret; @@ -513,8 +513,8 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data, if (obj == NULL) return -ENOENT;
+ mutex_lock(&dev->object_name_lock); idr_preload(GFP_KERNEL); - spin_lock(&dev->object_name_lock); /* prevent races with concurrent gem_close. */ if (obj->handle_count == 0) { ret = -ENOENT; @@ -536,8 +536,8 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data, ret = 0;
err: - spin_unlock(&dev->object_name_lock); idr_preload_end(); + mutex_unlock(&dev->object_name_lock); drm_gem_object_unreference_unlocked(obj); return ret; } @@ -560,11 +560,11 @@ drm_gem_open_ioctl(struct drm_device *dev, void *data, if (!(dev->driver->driver_features & DRIVER_GEM)) return -ENODEV;
- spin_lock(&dev->object_name_lock); + mutex_lock(&dev->object_name_lock); obj = idr_find(&dev->object_name_idr, (int) args->name); if (obj) drm_gem_object_reference(obj); - spin_unlock(&dev->object_name_lock); + mutex_unlock(&dev->object_name_lock); if (!obj) return -ENOENT;
diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 4d7ea3d..59a1cf1 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1229,7 +1229,7 @@ struct drm_device {
/** \name GEM information */ /*@{ */ - spinlock_t object_name_lock; + struct mutex object_name_lock; struct idr object_name_idr; /*@} */ int switch_power_state;