ext4: honor O_(D)SYNC semantic in ext4_fallocate()

Ext4 must make sure the transaction to be commited to the disk when
user opens a file with O_(D)SYNC flag and do a fallocate(2) call.

This problem had been reported by Christoph Hellwig in this thread:
http://www.spinics.net/lists/linux-btrfs/msg13621.html

Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Zheng Liu 2012-06-30 19:12:57 -04:00 committed by Theodore Ts'o
parent 1c8457cadc
commit f4e95b3316
1 changed files with 2 additions and 0 deletions

View File

@ -4420,6 +4420,8 @@ retry:
ext4_falloc_update_inode(inode, mode, new_size,
(map.m_flags & EXT4_MAP_NEW));
ext4_mark_inode_dirty(handle, inode);
if ((file->f_flags & O_SYNC) && ret >= max_blocks)
ext4_handle_sync(handle);
ret2 = ext4_journal_stop(handle);
if (ret2)
break;