ceph: clean up send_mds_reconnect interface

Pass a ceph_mds_session, since the caller has it.

Remove the dead code for sending empty reconnects.  It used to be used
when the MDS contacted _us_ to solicit a reconnect, and we could reply
saying "go away, I have no session."  Now we only send reconnects based
on the mds map, and only when we do in fact have an open session.

Signed-off-by: Sage Weil <sage@newdream.net>

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 972ec5a..e310b4b 100644 (file)
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2177,50 +2177,38 @@ out:
  *
  * called with mdsc->mutex held.
  */
-static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
+static void send_mds_reconnect(struct ceph_mds_client *mdsc,
+                              struct ceph_mds_session *session)
 {
-       struct ceph_mds_session *session = NULL;
        struct ceph_msg *reply;
        struct rb_node *p;
+       int mds = session->s_mds;
        int err = -ENOMEM;
        struct ceph_pagelist *pagelist;
 
-       pr_info("reconnect to recovering mds%d\n", mds);
+       pr_info("mds%d reconnect start\n", mds);
 
        pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
        if (!pagelist)
                goto fail_nopagelist;
        ceph_pagelist_init(pagelist);
 
-       err = -ENOMEM;
        reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0);
        if (!reply)
                goto fail_nomsg;
 
-       /* find session */
-       session = __ceph_lookup_mds_session(mdsc, mds);
-       mutex_unlock(&mdsc->mutex);    /* drop lock for duration */
-
-       if (session) {
-               mutex_lock(&session->s_mutex);
-
-               session->s_state = CEPH_MDS_SESSION_RECONNECTING;
-               session->s_seq = 0;
+       mutex_lock(&session->s_mutex);
+       session->s_state = CEPH_MDS_SESSION_RECONNECTING;
+       session->s_seq = 0;
 
-               ceph_con_open(&session->s_con,
-                             ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
+       ceph_con_open(&session->s_con,
+                     ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
 
-               /* replay unsafe requests */
-               replay_unsafe_requests(mdsc, session);
-       } else {
-               dout("no session for mds%d, will send short reconnect\n",
-                    mds);
-       }
+       /* replay unsafe requests */
+       replay_unsafe_requests(mdsc, session);
 
        down_read(&mdsc->snap_rwsem);
 
-       if (!session)
-               goto send;
        dout("session %p state %s\n", session,
             session_state_name(session->s_state));
 
@@ -2255,7 +2243,6 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
                        goto fail;
        }
 
-send:
        reply->pagelist = pagelist;
        reply->hdr.data_len = cpu_to_le32(pagelist->length);
        reply->nr_pages = calc_pages_for(0, pagelist->length);
@@ -2267,23 +2254,18 @@ send:
        __wake_requests(mdsc, &session->s_waiting);
        mutex_unlock(&mdsc->mutex);
 
-       ceph_put_mds_session(session);
-
        up_read(&mdsc->snap_rwsem);
-       mutex_lock(&mdsc->mutex);
        return;
 
 fail:
        ceph_msg_put(reply);
        up_read(&mdsc->snap_rwsem);
        mutex_unlock(&session->s_mutex);
-       ceph_put_mds_session(session);
 fail_nomsg:
        ceph_pagelist_release(pagelist);
        kfree(pagelist);
 fail_nopagelist:
        pr_err("error %d preparing reconnect for mds%d\n", err, mds);
-       mutex_lock(&mdsc->mutex);
        return;
 }
 
@@ -2345,8 +2327,11 @@ static void check_new_map(struct ceph_mds_client *mdsc,
                 * send reconnect?
                 */
                if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
-                   newstate >= CEPH_MDS_STATE_RECONNECT)
-                       send_mds_reconnect(mdsc, i);
+                   newstate >= CEPH_MDS_STATE_RECONNECT) {
+                       mutex_unlock(&mdsc->mutex);
+                       send_mds_reconnect(mdsc, s);
+                       mutex_lock(&mdsc->mutex);
+               }
 
                /*
                 * kick request on any mds that has gone active.