ext4: call blkdev_issue_flush on fsync

To ensure that bits are truly on-disk after an fsync,
we should call blkdev_issue_flush if barriers are supported.

Inspired by an old thread on barriers, by reiserfs & xfs
which do the same, and by a patch SuSE ships with their kernel

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Eric Sandeen 2008-07-11 19:27:31 -04:00 committed by Theodore Ts'o
parent 654b4908bc
commit d755fb3842

View File

@ -27,6 +27,7 @@
#include <linux/sched.h>
#include <linux/writeback.h>
#include <linux/jbd2.h>
#include <linux/blkdev.h>
#include "ext4.h"
#include "ext4_jbd2.h"
@ -45,6 +46,7 @@
int ext4_sync_file(struct file * file, struct dentry *dentry, int datasync)
{
struct inode *inode = dentry->d_inode;
journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
int ret = 0;
J_ASSERT(ext4_journal_current_handle() == NULL);
@ -85,6 +87,8 @@ int ext4_sync_file(struct file * file, struct dentry *dentry, int datasync)
.nr_to_write = 0, /* sys_fsync did this */
};
ret = sync_inode(inode, &wbc);
if (journal && (journal->j_flags & JBD2_BARRIER))
blkdev_issue_flush(inode->i_sb->s_bdev, NULL);
}
out:
return ret;