ext3: Use bitops to read/modify EXT3_I(inode)->i_state

At several places we modify EXT3_I(inode)->i_state without holding i_mutex
(ext3_release_file, ext3_bmap, ext3_journalled_writepage, ext3_do_update_inode,
...). These modifications are racy and we can lose updates to i_state. So
convert handling of i_state to use bitops which are atomic.

Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/include/linux/ext3_fs_i.h b/include/linux/ext3_fs_i.h
index 93e7428..7679acd 100644
--- a/include/linux/ext3_fs_i.h
+++ b/include/linux/ext3_fs_i.h
@@ -87,7 +87,7 @@
 	 * near to their parent directory's inode.
 	 */
 	__u32	i_block_group;
-	__u32	i_state;		/* Dynamic state flags for ext3 */
+	unsigned long	i_state;	/* Dynamic state flags for ext3 */
 
 	/* block reservation info */
 	struct ext3_block_alloc_info *i_block_alloc_info;