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()

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);
 

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);