ceph: remove req from unsafe list when unregistering it

commit df963ea8a082d31521a120e8e31a29ad8a1dc215 upstream.

There's no reason a request should ever be on a s_unsafe list but not
in the request tree.

Link: http://tracker.ceph.com/issues/18474
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 239bc9cba28ce8d4da09ecce617b6af9df80a1d2..f54f77037d22b56fa0c563d633160ae1b56e6fa5 100644 (file)
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -644,6 +644,9 @@ static void __unregister_request(struct ceph_mds_client *mdsc,
 {
        dout("__unregister_request %p tid %lld\n", req, req->r_tid);
 
+       /* Never leave an unregistered request on an unsafe list! */
+       list_del_init(&req->r_unsafe_item);
+
        if (req->r_tid == mdsc->oldest_tid) {
                struct rb_node *p = rb_next(&req->r_node);
                mdsc->oldest_tid = 0;
@@ -1051,7 +1054,6 @@ static void cleanup_session_requests(struct ceph_mds_client *mdsc,
        while (!list_empty(&session->s_unsafe)) {
                req = list_first_entry(&session->s_unsafe,
                                       struct ceph_mds_request, r_unsafe_item);
-               list_del_init(&req->r_unsafe_item);
                pr_warn_ratelimited(" dropping unsafe request %llu\n",
                                    req->r_tid);
                __unregister_request(mdsc, req);
@@ -2477,7 +2479,6 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
                         * useful we could do with a revised return value.
                         */
                        dout("got safe reply %llu, mds%d\n", tid, mds);
-                       list_del_init(&req->r_unsafe_item);
 
                        /* last unsafe request during umount? */
                        if (mdsc->stopping && !__get_oldest_req(mdsc))