gfs2: fix infinite loop in gfs2_ail1_flush on io error

Before this patch, an IO error encountered in function gfs2_ail1_flush
would cause a deadlock: because of the io error (and its resulting
withdrawn state), buffers stopped being written to the journal.
Buffers would remain on the ail1 list, so gfs2_ail1_start_one would
return 1 to indicate dirty buffers were still on the ail1 list.
However, when function gfs2_ail1_flush got a non-zero return code,
it would goto restart to retry the writes, which meant it would never
finish, and thus the infinite loop.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c
index 68af71eb28c61f151d7c1ba502c07dd6654c1c24..72c8f30b18229d80bca4af2dcc156fc45f8a1603 100644 (file)
--- a/fs/gfs2/log.c
+++ b/fs/gfs2/log.c
@@ -161,7 +161,8 @@ restart:
        list_for_each_entry_reverse(tr, head, tr_list) {
                if (wbc->nr_to_write <= 0)
                        break;
-               if (gfs2_ail1_start_one(sdp, wbc, tr, &withdraw))
+               if (gfs2_ail1_start_one(sdp, wbc, tr, &withdraw) &&
+                   !gfs2_withdrawn(sdp))
                        goto restart;
        }
        spin_unlock(&sdp->sd_ail_lock);