From: Fabian Frederick <fabf@skynet.be>
Date: Tue, 7 Apr 2015 23:43:50 +0000 (+1000)
Subject: fs/ext4/fsync.c: generic_file_fsync call based on barrier flag
X-Git-Tag: KARO-TXA5-2015-06-26~18^2~496
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a8dd381b912e1ad63ac2fc3f89ed4404aa2d1c7f;p=karo-tx-linux.git

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 a8bc47f75fa0..5b6e9f246233 100644
--- 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;