fs/ext4/fsync.c: generic_file_fsync call based on barrier flag

generic_file_fsync has been updated to issue a flush for older
filesystems.

This patch tests for barrier flag in ext4 mount flags and calls the right
function.

Lukas said:

: Note that the actual generic_file_fsync change fixes a real bug in ext4
: where we would _not_ send a flush on sync if we have file system
: without journal.
:
: Ted, it would be useful to mention that in the commit description
: along with the commit id:
:
: ac13a829f6adb674015ab399594c089990104af7 fs/libfs.c: add generic
: data flush to fsync

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Suggested-by: Jan Kara <jack@suse.cz>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index a8bc47f75fa0946582ce5562ebdea334cead1ac6..5b6e9f2462331f7750bc80ecc38f9349f0b5a5de 100644 (file)
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -107,7 +107,10 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
        }
 
        if (!journal) {
-               ret = generic_file_fsync(file, start, end, datasync);
+               if (test_opt(inode->i_sb, BARRIER))
+                       ret = generic_file_fsync(file, start, end, datasync);
+               else
+                       ret = __generic_file_fsync(file, start, end, datasync);
                if (!ret && !hlist_empty(&inode->i_dentry))
                        ret = ext4_sync_parent(inode);
                goto out;