---

yaml
---
r: 145014
b: refs/heads/master
c: 2a8964d
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 33b9817e2ae097c7b8d256e3510ac6c54fc6d9d0
+refs/heads/master: 2a8964d63d50dd2d65d71d342bc7fb6ef4117614

trunk/fs/ext4/inode.c

@@ -1149,6 +1149,7 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
 	int retval;
 
 	clear_buffer_mapped(bh);
+	clear_buffer_unwritten(bh);
 
 	/*
 	 * Try to see if we can get  the block without requesting
@@ -1178,6 +1179,18 @@ int ext4_get_blocks_wrap(handle_t *handle, struct inode *inode, sector_t block,
 	if (retval > 0 && buffer_mapped(bh))
 		return retval;
 
+	/*
+	 * When we call get_blocks without the create flag, the
+	 * BH_Unwritten flag could have gotten set if the blocks
+	 * requested were part of a uninitialized extent.  We need to
+	 * clear this flag now that we are committed to convert all or
+	 * part of the uninitialized extent to be an initialized
+	 * extent.  This is because we need to avoid the combination
+	 * of BH_Unwritten and BH_Mapped flags being simultaneously
+	 * set on the buffer_head.
+	 */
+	clear_buffer_unwritten(bh);
+
 	/*
 	 * New blocks allocate and/or writing to uninitialized extent
 	 * will possibly result in updating i_data, so we take