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>

1 files changed, 16 insertions, 31 deletions

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 972ec5ae2ac4..e310b4be5588 100644
--- 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.