ext4: call blkdev_issue_flush on fsync From: Eric Sandeen 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 Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/fsync.c | 4 ++++ 1 file changed, 4 insertions(+) Index: linux-2.6.26-rc9/fs/ext4/fsync.c =================================================================== --- linux-2.6.26-rc9.orig/fs/ext4/fsync.c 2008-07-11 16:04:29.000000000 -0700 +++ linux-2.6.26-rc9/fs/ext4/fsync.c 2008-07-11 16:05:06.000000000 -0700 @@ -27,6 +27,7 @@ #include #include #include +#include #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, s .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;