[RFC PATCH 4/4] ceph: queue request when CLEANRECOVER is set

[Jeff Layton <jlayton@kernel.org>]

Ilya noticed that the first access to a blacklisted mount would often
get back -EACCES, but then subsequent calls would be OK. The problem is
in __do_request. If the session is marked as REJECTED, a hard error is
returned instead of waiting for a new session to come into being.

When the session is REJECTED and the mount was done with
recover_session=clean, queue the request to the waiting_for_map queue,
which will be awoken after tearing down the old session.

URL: https://tracker.ceph.com/issues/47385
Reported-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/ceph/mds_client.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index fd16db6ecb0a..b07e7adf146f 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2819,7 +2819,10 @@ static void __do_request(struct ceph_mds_client *mdsc,
 	if (session->s_state != CEPH_MDS_SESSION_OPEN &&
 	    session->s_state != CEPH_MDS_SESSION_HUNG) {
 		if (session->s_state == CEPH_MDS_SESSION_REJECTED) {
-			err = -EACCES;
+			if (ceph_test_mount_opt(mdsc->fsc, CLEANRECOVER))
+				list_add(&req->r_wait, &mdsc->waiting_for_map);
+			else
+				err = -EACCES;
 			goto out_session;
 		}
 		/*
-- 
2.26.2