[PATCH 11/18] drm/armada: Don't grab dev->struct_mutex for in mmap offset ioctl

[Daniel Vetter]

Since David Herrmann's mmap vma manager rework we don't need to grab
dev->struct_mutex any more to prevent races when looking up the mmap
offset. Drop it and instead don't forget to use the unref_unlocked
variant (since the drm core still cares).

While at it also fix a leak when this ioctl is called on an imported
buffer.

Cc: Russell King <rmk+kernel at arm.linux.org.uk>
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
---
 drivers/gpu/drm/armada/armada_gem.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/armada/armada_gem.c b/drivers/gpu/drm/armada/armada_gem.c
index 580e10acaa3a..95df74227ec0 100644
--- a/drivers/gpu/drm/armada/armada_gem.c
+++ b/drivers/gpu/drm/armada/armada_gem.c
@@ -273,18 +273,16 @@ int armada_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
 	struct armada_gem_object *obj;
 	int ret = 0;
 
-	mutex_lock(&dev->struct_mutex);
 	obj = armada_gem_object_lookup(dev, file, handle);
 	if (!obj) {
 		DRM_ERROR("failed to lookup gem object\n");
-		ret = -EINVAL;
-		goto err_unlock;
+		return -EINVAL;
 	}
 
 	/* Don't allow imported objects to be mapped */
 	if (obj->obj.import_attach) {
 		ret = -EINVAL;
-		goto err_unlock;
+		goto err_unref;
 	}
 
 	ret = drm_gem_create_mmap_offset(&obj->obj);
@@ -293,9 +291,8 @@ int armada_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
 		DRM_DEBUG_DRIVER("handle %#x offset %llx\n", handle, *offset);
 	}
 
-	drm_gem_object_unreference(&obj->obj);
- err_unlock:
-	mutex_unlock(&dev->struct_mutex);
+err_unref:
+	drm_gem_object_unreference_unlocked(&obj->obj);
 
 	return ret;
 }
-- 
2.1.4