drm/vmwgfx: Fix a circular locking dependency bug.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index 3e4e670..356dc93 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -113,6 +113,7 @@
 	unsigned long static_buffer_size;
 	bool using_bounce_buffer;
 	uint32_t capabilities;
+	struct mutex fifo_mutex;
 	struct rw_semaphore rwsem;
 };
 
@@ -213,7 +214,7 @@
 	 * Fencing and IRQs.
 	 */
 
-	uint32_t fence_seq;
+	atomic_t fence_seq;
 	wait_queue_head_t fence_queue;
 	wait_queue_head_t fifo_queue;
 	atomic_t fence_queue_waiters;