ext4: Enable extent format for symlinks.

This patch enables extent-formatted normal symlinks.  Using extents
format allows a symlink to refer to a block number larger than 2^32
on large filesystems.  We still don't enable extent format for fast
symlinks, which are contained in the inode itself.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 28aa2ed..6861194 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2217,6 +2217,8 @@
 			goto out_stop;
 		}
 	} else {
+		/* clear the extent format for fast symlink */
+		EXT4_I(inode)->i_flags &= ~EXT4_EXTENTS_FL;
 		inode->i_op = &ext4_fast_symlink_inode_operations;
 		memcpy((char*)&EXT4_I(inode)->i_data,symname,l);
 		inode->i_size = l-1;