ocfs2/dlm: Handle EAGAIN for compatibility - v2

Mainline commit aad1b15310b9bcd59fa81ab8f2b1513b59553ea8 made the
dlm_begin_reco_handler() return -EAGAIN instead of EAGAIN.

As this error is transmitted over the wire, we want the receiver,
dlm_send_begin_reco_message(), to understand both the older EAGAIN and
the newer -EAGAIN, to allow rolling upgrade of the cluster nodes.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c
index cfb2ae9ab538..ad712211d4ea 100644
--- a/fs/ocfs2/dlm/dlmrecovery.c
+++ b/fs/ocfs2/dlm/dlmrecovery.c
@@ -2639,7 +2639,13 @@ retry:
                              "begin reco msg (%d)\n", dlm->name, nodenum, ret);
                         ret = 0;
                 }
-                if (ret == -EAGAIN) {
+
+                /*
+                 * Prior to commit aad1b15310b9bcd59fa81ab8f2b1513b59553ea8,
+                 * dlm_begin_reco_handler() returned EAGAIN and not -EAGAIN.
+                 * We are handling both for compatibility reasons.
+                 */
+                if (ret == -EAGAIN || ret == EAGAIN) {
                         mlog(0, "%s: trying to start recovery of node "
                              "%u, but node %u is waiting for last recovery "
                              "to complete, backoff for a bit\n", dlm->name,