Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

Pull Ceph fixes from Sage Weil:
 "Two of Alex's patches deal with a race when reseting server
  connections for open RBD images, one demotes some non-fatal BUGs to
  WARNs, and my patch fixes a protocol feature bit failure path."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  libceph: fix protocol feature mismatch failure path
  libceph: WARN, don't BUG on unexpected connection states
  libceph: always reset osds when kicking
  libceph: move linger requests sooner in kick_requests()

2 files changed, 29 insertions, 28 deletions

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 4d111fd2b492..5ccf87ed8d68 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -506,6 +506,7 @@ static void reset_connection(struct ceph_connection *con)
 {
         /* reset connection, out_queue, msg_ and connect_seq */
         /* discard existing out_queue and msg_seq */
+        dout("reset_connection %p\n", con);
         ceph_msg_remove_list(&con->out_queue);
         ceph_msg_remove_list(&con->out_sent);
 
@@ -561,7 +562,7 @@ void ceph_con_open(struct ceph_connection *con,
         mutex_lock(&con->mutex);
         dout("con_open %p %s\n", con, ceph_pr_addr(&addr->in_addr));
 
-        BUG_ON(con->state != CON_STATE_CLOSED);
+        WARN_ON(con->state != CON_STATE_CLOSED);
         con->state = CON_STATE_PREOPEN;
 
         con->peer_name.type = (__u8) entity_type;
@@ -1506,13 +1507,6 @@ static int process_banner(struct ceph_connection *con)
         return 0;
 }
 
-static void fail_protocol(struct ceph_connection *con)
-{
-        reset_connection(con);
-        BUG_ON(con->state != CON_STATE_NEGOTIATING);
-        con->state = CON_STATE_CLOSED;
-}
-
 static int process_connect(struct ceph_connection *con)
 {
         u64 sup_feat = con->msgr->supported_features;
@@ -1530,7 +1524,7 @@ static int process_connect(struct ceph_connection *con)
                        ceph_pr_addr(&con->peer_addr.in_addr),
                        sup_feat, server_feat, server_feat & ~sup_feat);
                 con->error_msg = "missing required protocol features";
-                fail_protocol(con);
+                reset_connection(con);
                 return -1;
 
         case CEPH_MSGR_TAG_BADPROTOVER:
@@ -1541,7 +1535,7 @@ static int process_connect(struct ceph_connection *con)
                        le32_to_cpu(con->out_connect.protocol_version),
                        le32_to_cpu(con->in_reply.protocol_version));
                 con->error_msg = "protocol version mismatch";
-                fail_protocol(con);
+                reset_connection(con);
                 return -1;
 
         case CEPH_MSGR_TAG_BADAUTHORIZER:
@@ -1631,11 +1625,11 @@ static int process_connect(struct ceph_connection *con)
                                ceph_pr_addr(&con->peer_addr.in_addr),
                                req_feat, server_feat, req_feat & ~server_feat);
                         con->error_msg = "missing required protocol features";
-                        fail_protocol(con);
+                        reset_connection(con);
                         return -1;
                 }
 
-                BUG_ON(con->state != CON_STATE_NEGOTIATING);
+                WARN_ON(con->state != CON_STATE_NEGOTIATING);
                 con->state = CON_STATE_OPEN;
 
                 con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
@@ -2132,7 +2126,6 @@ more:
                 if (ret < 0)
                         goto out;
 
-                BUG_ON(con->state != CON_STATE_CONNECTING);
                 con->state = CON_STATE_NEGOTIATING;
 
                 /*
@@ -2160,7 +2153,7 @@ more:
                 goto more;
         }
 
-        BUG_ON(con->state != CON_STATE_OPEN);
+        WARN_ON(con->state != CON_STATE_OPEN);
 
         if (con->in_base_pos < 0) {
                 /*
@@ -2382,7 +2375,7 @@ static void ceph_fault(struct ceph_connection *con)
         dout("fault %p state %lu to peer %s\n",
              con, con->state, ceph_pr_addr(&con->peer_addr.in_addr));
 
-        BUG_ON(con->state != CON_STATE_CONNECTING &&
+        WARN_ON(con->state != CON_STATE_CONNECTING &&
                con->state != CON_STATE_NEGOTIATING &&
                con->state != CON_STATE_OPEN);
 
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 780caf6b0491..eb9a44478764 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -1270,7 +1270,7 @@ static void reset_changed_osds(struct ceph_osd_client *osdc)
  * Requeue requests whose mapping to an OSD has changed.  If requests map to
  * no osd, request a new map.
  *
- * Caller should hold map_sem for read and request_mutex.
+ * Caller should hold map_sem for read.
  */
 static void kick_requests(struct ceph_osd_client *osdc, int force_resend)
 {
@@ -1284,6 +1284,24 @@ static void kick_requests(struct ceph_osd_client *osdc, int force_resend)
         for (p = rb_first(&osdc->requests); p; ) {
                 req = rb_entry(p, struct ceph_osd_request, r_node);
                 p = rb_next(p);
+
+                /*
+                 * For linger requests that have not yet been
+                 * registered, move them to the linger list; they'll
+                 * be sent to the osd in the loop below.  Unregister
+                 * the request before re-registering it as a linger
+                 * request to ensure the __map_request() below
+                 * will decide it needs to be sent.
+                 */
+                if (req->r_linger && list_empty(&req->r_linger_item)) {
+                        dout("%p tid %llu restart on osd%d\n",
+                             req, req->r_tid,
+                             req->r_osd ? req->r_osd->o_osd : -1);
+                        __unregister_request(osdc, req);
+                        __register_linger_request(osdc, req);
+                        continue;
+                }
+
                 err = __map_request(osdc, req, force_resend);
                 if (err < 0)
                         continue;  /* error */
@@ -1298,17 +1316,6 @@ static void kick_requests(struct ceph_osd_client *osdc, int force_resend)
                                 req->r_flags |= CEPH_OSD_FLAG_RETRY;
                         }
                 }
-                if (req->r_linger && list_empty(&req->r_linger_item)) {
-                        /*
-                         * register as a linger so that we will
-                         * re-submit below and get a new tid
-                         */
-                        dout("%p tid %llu restart on osd%d\n",
-                             req, req->r_tid,
-                             req->r_osd ? req->r_osd->o_osd : -1);
-                        __register_linger_request(osdc, req);
-                        __unregister_request(osdc, req);
-                }
         }
 
         list_for_each_entry_safe(req, nreq, &osdc->req_linger,
@@ -1316,6 +1323,7 @@ static void kick_requests(struct ceph_osd_client *osdc, int force_resend)
                 dout("linger req=%p req->r_osd=%p\n", req, req->r_osd);
 
                 err = __map_request(osdc, req, force_resend);
+                dout("__map_request returned %d\n", err);
                 if (err == 0)
                         continue;  /* no change and no osd was specified */
                 if (err < 0)
@@ -1337,6 +1345,7 @@ static void kick_requests(struct ceph_osd_client *osdc, int force_resend)
                 dout("%d requests for down osds, need new map\n", needmap);
                 ceph_monc_request_next_osdmap(&osdc->client->monc);
         }
+        reset_changed_osds(osdc);
 }
 
 
@@ -1393,7 +1402,6 @@ void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
                                 osdc->osdmap = newmap;
                         }
                         kick_requests(osdc, 0);
-                        reset_changed_osds(osdc);
                 } else {
                         dout("ignoring incremental map %u len %d\n",
                              epoch, maplen);