[GFS2] Add writepages for GFS2 jdata

This patch resolves a lock ordering issue where we had been getting
a transaction lock in the wrong order with respect to the page lock.
By using writepages rather than just writepage, it is then possible
to start a transaction before locking the page, and thus matching the
locking order elsewhere in the code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index 70b404d2774b..1e1fe8def375 100644
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -650,7 +650,7 @@ static void gfs2_ordered_write(struct gfs2_sbd *sdp)
                 get_bh(bh);
                 gfs2_log_unlock(sdp);
                 lock_buffer(bh);
-                if (test_clear_buffer_dirty(bh)) {
+                if (buffer_mapped(bh) && test_clear_buffer_dirty(bh)) {
                         bh->b_end_io = end_buffer_write_sync;
                         submit_bh(WRITE, bh);
                 } else {