diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 911d64d865f1..b43399d22e23 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -3764,7 +3764,6 @@ void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
 	dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
 
 	/* do we need it? */
-	ceph_monc_got_mdsmap(&mdsc->fsc->client->monc, epoch);
 	mutex_lock(&mdsc->mutex);
 	if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
 		dout("handle_map epoch %u <= our %u\n",
@@ -3791,6 +3790,8 @@ void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
 	mdsc->fsc->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
 
 	__wake_requests(mdsc, &mdsc->waiting_for_map);
+	ceph_monc_got_map(&mdsc->fsc->client->monc, CEPH_SUB_MDSMAP,
+			  mdsc->mdsmap->m_epoch);
 
 	mutex_unlock(&mdsc->mutex);
 	schedule_delayed(mdsc);
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index ca4d5e8457f1..c941fd1a8eb8 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -530,7 +530,7 @@ static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 		goto fail;
 	}
 	fsc->client->extra_mon_dispatch = extra_mon_dispatch;
-	fsc->client->monc.want_mdsmap = 1;
+	ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP, 0, true);
 
 	fsc->mount_options = fsopt;
 
diff --git a/include/linux/ceph/ceph_features.h b/include/linux/ceph/ceph_features.h
index 15151f3c4120..ae2f66833762 100644
--- a/include/linux/ceph/ceph_features.h
+++ b/include/linux/ceph/ceph_features.h
@@ -105,6 +105,7 @@ static inline u64 ceph_sanitize_features(u64 features)
  */
 #define CEPH_FEATURES_SUPPORTED_DEFAULT		\
 	(CEPH_FEATURE_NOSRCADDR |		\
+	 CEPH_FEATURE_SUBSCRIBE2 |		\
 	 CEPH_FEATURE_RECONNECT_SEQ |		\
 	 CEPH_FEATURE_PGID64 |			\
 	 CEPH_FEATURE_PGPOOL3 |			\
@@ -127,6 +128,7 @@ static inline u64 ceph_sanitize_features(u64 features)
 
 #define CEPH_FEATURES_REQUIRED_DEFAULT   \
 	(CEPH_FEATURE_NOSRCADDR |	 \
+	 CEPH_FEATURE_SUBSCRIBE2 |	 \
 	 CEPH_FEATURE_RECONNECT_SEQ |	 \
 	 CEPH_FEATURE_PGID64 |		 \
 	 CEPH_FEATURE_PGPOOL3 |		 \
diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h
index d7d072a25c27..bf74005eedec 100644
--- a/include/linux/ceph/ceph_fs.h
+++ b/include/linux/ceph/ceph_fs.h
@@ -198,8 +198,8 @@ struct ceph_client_mount {
 #define CEPH_SUBSCRIBE_ONETIME    1  /* i want only 1 update after have */
 
 struct ceph_mon_subscribe_item {
-	__le64 have_version;    __le64 have;
-	__u8 onetime;
+	__le64 start;
+	__u8 flags;
 } __attribute__ ((packed));
 
 struct ceph_mon_subscribe_ack {
diff --git a/include/linux/ceph/mon_client.h b/include/linux/ceph/mon_client.h
index 81810dc21f06..8b2d2f0b659e 100644
--- a/include/linux/ceph/mon_client.h
+++ b/include/linux/ceph/mon_client.h
@@ -68,7 +68,8 @@ struct ceph_mon_client {
 
 	bool hunting;
 	int cur_mon;                       /* last monitor i contacted */
-	unsigned long sub_sent, sub_renew_after;
+	unsigned long sub_renew_after;
+	unsigned long sub_renew_sent;
 	struct ceph_connection con;
 
 	/* pending generic requests */
@@ -76,10 +77,12 @@ struct ceph_mon_client {
 	int num_generic_requests;
 	u64 last_tid;
 
-	/* mds/osd map */
-	int want_mdsmap;
-	int want_next_osdmap; /* 1 = want, 2 = want+asked */
-	u32 have_osdmap, have_mdsmap;
+	/* subs, indexed with CEPH_SUB_* */
+	struct {
+		struct ceph_mon_subscribe_item item;
+		bool want;
+		u32 have; /* epoch */
+	} subs[3];
 
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debugfs_file;
@@ -93,14 +96,23 @@ extern int ceph_monmap_contains(struct ceph_monmap *m,
 extern int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl);
 extern void ceph_monc_stop(struct ceph_mon_client *monc);
 
+enum {
+	CEPH_SUB_MDSMAP = 0,
+	CEPH_SUB_MONMAP,
+	CEPH_SUB_OSDMAP,
+};
+
+extern const char *ceph_sub_str[];
+
 /*
  * The model here is to indicate that we need a new map of at least
- * epoch @want, and also call in when we receive a map.  We will
+ * epoch @epoch, and also call in when we receive a map.  We will
  * periodically rerequest the map from the monitor cluster until we
  * get what we want.
  */
-extern int ceph_monc_got_mdsmap(struct ceph_mon_client *monc, u32 have);
-extern int ceph_monc_got_osdmap(struct ceph_mon_client *monc, u32 have);
+bool ceph_monc_want_map(struct ceph_mon_client *monc, int sub, u32 epoch,
+			bool continuous);
+void ceph_monc_got_map(struct ceph_mon_client *monc, int sub, u32 epoch);
 
 extern void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc);
 extern int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
diff --git a/net/ceph/debugfs.c b/net/ceph/debugfs.c
index 593dc2eabcc8..b902fbc7863e 100644
--- a/net/ceph/debugfs.c
+++ b/net/ceph/debugfs.c
@@ -112,15 +112,20 @@ static int monc_show(struct seq_file *s, void *p)
 	struct ceph_mon_generic_request *req;
 	struct ceph_mon_client *monc = &client->monc;
 	struct rb_node *rp;
+	int i;
 
 	mutex_lock(&monc->mutex);
 
-	if (monc->have_mdsmap)
-		seq_printf(s, "have mdsmap %u\n", (unsigned int)monc->have_mdsmap);
-	if (monc->have_osdmap)
-		seq_printf(s, "have osdmap %u\n", (unsigned int)monc->have_osdmap);
-	if (monc->want_next_osdmap)
-		seq_printf(s, "want next osdmap\n");
+	for (i = 0; i < ARRAY_SIZE(monc->subs); i++) {
+		seq_printf(s, "have %s %u", ceph_sub_str[i],
+			   monc->subs[i].have);
+		if (monc->subs[i].want)
+			seq_printf(s, " want %llu%s",
+				   le64_to_cpu(monc->subs[i].item.start),
+				   (monc->subs[i].item.flags &
+					CEPH_SUBSCRIBE_ONETIME ?  "" : "+"));
+		seq_putc(s, '\n');
+	}
 
 	for (rp = rb_first(&monc->generic_request_tree); rp; rp = rb_next(rp)) {
 		__u16 op;
diff --git a/net/ceph/mon_client.c b/net/ceph/mon_client.c
index d6af6ca26e8d..89029916315c 100644
--- a/net/ceph/mon_client.c
+++ b/net/ceph/mon_client.c
@@ -140,9 +140,8 @@ static int __open_session(struct ceph_mon_client *monc)
 		monc->cur_mon = r % monc->monmap->num_mon;
 		dout("open_session num=%d r=%d -> mon%d\n",
 		     monc->monmap->num_mon, r, monc->cur_mon);
-		monc->sub_sent = 0;
 		monc->sub_renew_after = jiffies;  /* i.e., expired */
-		monc->want_next_osdmap = !!monc->want_next_osdmap;
+		monc->sub_renew_sent = 0;
 
 		dout("open_session mon%d opening\n", monc->cur_mon);
 		ceph_con_open(&monc->con,
@@ -189,59 +188,58 @@ static void __schedule_delayed(struct ceph_mon_client *monc)
 			      round_jiffies_relative(delay));
 }
 
+const char *ceph_sub_str[] = {
+	[CEPH_SUB_MDSMAP] = "mdsmap",
+	[CEPH_SUB_MONMAP] = "monmap",
+	[CEPH_SUB_OSDMAP] = "osdmap",
+};
+
 /*
- * Send subscribe request for mdsmap and/or osdmap.
+ * Send subscribe request for one or more maps, according to
+ * monc->subs.
  */
 static void __send_subscribe(struct ceph_mon_client *monc)
 {
-	dout("__send_subscribe sub_sent=%u exp=%u want_osd=%d\n",
-	     (unsigned int)monc->sub_sent, __sub_expired(monc),
-	     monc->want_next_osdmap);
-	if ((__sub_expired(monc) && !monc->sub_sent) ||
-	    monc->want_next_osdmap == 1) {
-		struct ceph_msg *msg = monc->m_subscribe;
-		struct ceph_mon_subscribe_item *i;
-		void *p, *end;
-		int num;
+	struct ceph_msg *msg = monc->m_subscribe;
+	void *p = msg->front.iov_base;
+	void *const end = p + msg->front_alloc_len;
+	int num = 0;
+	int i;
 
-		p = msg->front.iov_base;
-		end = p + msg->front_alloc_len;
+	dout("%s sent %lu\n", __func__, monc->sub_renew_sent);
 
-		num = 1 + !!monc->want_next_osdmap + !!monc->want_mdsmap;
-		ceph_encode_32(&p, num);
+	BUG_ON(monc->cur_mon < 0);
 
-		if (monc->want_next_osdmap) {
-			dout("__send_subscribe to 'osdmap' %u\n",
-			     (unsigned int)monc->have_osdmap);
-			ceph_encode_string(&p, end, "osdmap", 6);
-			i = p;
-			i->have = cpu_to_le64(monc->have_osdmap);
-			i->onetime = 1;
-			p += sizeof(*i);
-			monc->want_next_osdmap = 2;  /* requested */
-		}
-		if (monc->want_mdsmap) {
-			dout("__send_subscribe to 'mdsmap' %u+\n",
-			     (unsigned int)monc->have_mdsmap);
-			ceph_encode_string(&p, end, "mdsmap", 6);
-			i = p;
-			i->have = cpu_to_le64(monc->have_mdsmap);
-			i->onetime = 0;
-			p += sizeof(*i);
-		}
-		ceph_encode_string(&p, end, "monmap", 6);
-		i = p;
-		i->have = 0;
-		i->onetime = 0;
-		p += sizeof(*i);
+	if (!monc->sub_renew_sent)
+		monc->sub_renew_sent = jiffies | 1; /* never 0 */
 
-		msg->front.iov_len = p - msg->front.iov_base;
-		msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
-		ceph_msg_revoke(msg);
-		ceph_con_send(&monc->con, ceph_msg_get(msg));
+	msg->hdr.version = cpu_to_le16(2);
 
-		monc->sub_sent = jiffies | 1;  /* never 0 */
+	for (i = 0; i < ARRAY_SIZE(monc->subs); i++) {
+		if (monc->subs[i].want)
+			num++;
 	}
+	BUG_ON(num < 1); /* monmap sub is always there */
+	ceph_encode_32(&p, num);
+	for (i = 0; i < ARRAY_SIZE(monc->subs); i++) {
+		const char *s = ceph_sub_str[i];
+
+		if (!monc->subs[i].want)
+			continue;
+
+		dout("%s %s start %llu flags 0x%x\n", __func__, s,
+		     le64_to_cpu(monc->subs[i].item.start),
+		     monc->subs[i].item.flags);
+		ceph_encode_string(&p, end, s, strlen(s));
+		memcpy(p, &monc->subs[i].item, sizeof(monc->subs[i].item));
+		p += sizeof(monc->subs[i].item);
+	}
+
+	BUG_ON(p != (end - 35 - (ARRAY_SIZE(monc->subs) - num) * 19));
+	msg->front.iov_len = p - msg->front.iov_base;
+	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
+	ceph_msg_revoke(msg);
+	ceph_con_send(&monc->con, ceph_msg_get(msg));
 }
 
 static void handle_subscribe_ack(struct ceph_mon_client *monc,
@@ -255,9 +253,16 @@ static void handle_subscribe_ack(struct ceph_mon_client *monc,
 	seconds = le32_to_cpu(h->duration);
 
 	mutex_lock(&monc->mutex);
-	dout("handle_subscribe_ack after %d seconds\n", seconds);
-	monc->sub_renew_after = monc->sub_sent + (seconds >> 1)*HZ - 1;
-	monc->sub_sent = 0;
+	if (monc->sub_renew_sent) {
+		monc->sub_renew_after = monc->sub_renew_sent +
+					    (seconds >> 1) * HZ - 1;
+		dout("%s sent %lu duration %d renew after %lu\n", __func__,
+		     monc->sub_renew_sent, seconds, monc->sub_renew_after);
+		monc->sub_renew_sent = 0;
+	} else {
+		dout("%s sent %lu renew after %lu, ignoring\n", __func__,
+		     monc->sub_renew_sent, monc->sub_renew_after);
+	}
 	mutex_unlock(&monc->mutex);
 	return;
 bad:
@@ -266,36 +271,82 @@ bad:
 }
 
 /*
- * Keep track of which maps we have
+ * Register interest in a map
+ *
+ * @sub: one of CEPH_SUB_*
+ * @epoch: X for "every map since X", or 0 for "just the latest"
  */
-int ceph_monc_got_mdsmap(struct ceph_mon_client *monc, u32 got)
+static bool __ceph_monc_want_map(struct ceph_mon_client *monc, int sub,
+				 u32 epoch, bool continuous)
 {
-	mutex_lock(&monc->mutex);
-	monc->have_mdsmap = got;
-	mutex_unlock(&monc->mutex);
-	return 0;
-}
-EXPORT_SYMBOL(ceph_monc_got_mdsmap);
+	__le64 start = cpu_to_le64(epoch);
+	u8 flags = !continuous ? CEPH_SUBSCRIBE_ONETIME : 0;
 
-int ceph_monc_got_osdmap(struct ceph_mon_client *monc, u32 got)
+	dout("%s %s epoch %u continuous %d\n", __func__, ceph_sub_str[sub],
+	     epoch, continuous);
+
+	if (monc->subs[sub].want &&
+	    monc->subs[sub].item.start == start &&
+	    monc->subs[sub].item.flags == flags)
+		return false;
+
+	monc->subs[sub].item.start = start;
+	monc->subs[sub].item.flags = flags;
+	monc->subs[sub].want = true;
+
+	return true;
+}
+
+bool ceph_monc_want_map(struct ceph_mon_client *monc, int sub, u32 epoch,
+			bool continuous)
+{
+	bool need_request;
+
+	mutex_lock(&monc->mutex);
+	need_request = __ceph_monc_want_map(monc, sub, epoch, continuous);
+	mutex_unlock(&monc->mutex);
+
+	return need_request;
+}
+EXPORT_SYMBOL(ceph_monc_want_map);
+
+/*
+ * Keep track of which maps we have
+ *
+ * @sub: one of CEPH_SUB_*
+ */
+static void __ceph_monc_got_map(struct ceph_mon_client *monc, int sub,
+				u32 epoch)
+{
+	dout("%s %s epoch %u\n", __func__, ceph_sub_str[sub], epoch);
+
+	if (monc->subs[sub].want) {
+		if (monc->subs[sub].item.flags & CEPH_SUBSCRIBE_ONETIME)
+			monc->subs[sub].want = false;
+		else
+			monc->subs[sub].item.start = cpu_to_le64(epoch + 1);
+	}
+
+	monc->subs[sub].have = epoch;
+}
+
+void ceph_monc_got_map(struct ceph_mon_client *monc, int sub, u32 epoch)
 {
 	mutex_lock(&monc->mutex);
-	monc->have_osdmap = got;
-	monc->want_next_osdmap = 0;
+	__ceph_monc_got_map(monc, sub, epoch);
 	mutex_unlock(&monc->mutex);
-	return 0;
 }
+EXPORT_SYMBOL(ceph_monc_got_map);
 
 /*
  * Register interest in the next osdmap
  */
 void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc)
 {
-	dout("request_next_osdmap have %u\n", monc->have_osdmap);
+	dout("%s have %u\n", __func__, monc->subs[CEPH_SUB_OSDMAP].have);
 	mutex_lock(&monc->mutex);
-	if (!monc->want_next_osdmap)
-		monc->want_next_osdmap = 1;
-	if (monc->want_next_osdmap < 2)
+	if (__ceph_monc_want_map(monc, CEPH_SUB_OSDMAP,
+				 monc->subs[CEPH_SUB_OSDMAP].have + 1, false))
 		__send_subscribe(monc);
 	mutex_unlock(&monc->mutex);
 }
@@ -314,15 +365,15 @@ int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
 	long ret;
 
 	mutex_lock(&monc->mutex);
-	while (monc->have_osdmap < epoch) {
+	while (monc->subs[CEPH_SUB_OSDMAP].have < epoch) {
 		mutex_unlock(&monc->mutex);
 
 		if (timeout && time_after_eq(jiffies, started + timeout))
 			return -ETIMEDOUT;
 
 		ret = wait_event_interruptible_timeout(monc->client->auth_wq,
-						monc->have_osdmap >= epoch,
-						ceph_timeout_jiffies(timeout));
+				     monc->subs[CEPH_SUB_OSDMAP].have >= epoch,
+				     ceph_timeout_jiffies(timeout));
 		if (ret < 0)
 			return ret;
 
@@ -335,11 +386,14 @@ int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
 EXPORT_SYMBOL(ceph_monc_wait_osdmap);
 
 /*
- *
+ * Open a session with a random monitor.  Request monmap and osdmap,
+ * which are waited upon in __ceph_open_session().
  */
 int ceph_monc_open_session(struct ceph_mon_client *monc)
 {
 	mutex_lock(&monc->mutex);
+	__ceph_monc_want_map(monc, CEPH_SUB_MONMAP, 0, true);
+	__ceph_monc_want_map(monc, CEPH_SUB_OSDMAP, 0, false);
 	__open_session(monc);
 	__schedule_delayed(monc);
 	mutex_unlock(&monc->mutex);
@@ -375,6 +429,7 @@ static void ceph_monc_handle_map(struct ceph_mon_client *monc,
 	client->monc.monmap = monmap;
 	kfree(old);
 
+	__ceph_monc_got_map(monc, CEPH_SUB_MONMAP, monc->monmap->epoch);
 	client->have_fsid = true;
 
 out:
@@ -725,8 +780,14 @@ static void delayed_work(struct work_struct *work)
 			__validate_auth(monc);
 		}
 
-		if (is_auth)
-			__send_subscribe(monc);
+		if (is_auth) {
+			unsigned long now = jiffies;
+
+			dout("%s renew subs? now %lu renew after %lu\n",
+			     __func__, now, monc->sub_renew_after);
+			if (time_after_eq(now, monc->sub_renew_after))
+				__send_subscribe(monc);
+		}
 	}
 	__schedule_delayed(monc);
 	mutex_unlock(&monc->mutex);
@@ -815,16 +876,13 @@ int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
 	monc->cur_mon = -1;
 	monc->hunting = true;
 	monc->sub_renew_after = jiffies;
-	monc->sub_sent = 0;
+	monc->sub_renew_sent = 0;
 
 	INIT_DELAYED_WORK(&monc->delayed_work, delayed_work);
 	monc->generic_request_tree = RB_ROOT;
 	monc->num_generic_requests = 0;
 	monc->last_tid = 0;
 
-	monc->have_mdsmap = 0;
-	monc->have_osdmap = 0;
-	monc->want_next_osdmap = 1;
 	return 0;
 
 out_auth_reply:
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 5bc053778fed..3309112e23d0 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -2187,7 +2187,8 @@ void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
 		goto bad;
 done:
 	downgrade_write(&osdc->map_sem);
-	ceph_monc_got_osdmap(&osdc->client->monc, osdc->osdmap->epoch);
+	ceph_monc_got_map(&osdc->client->monc, CEPH_SUB_OSDMAP,
+			  osdc->osdmap->epoch);
 
 	/*
 	 * subscribe to subsequent osdmap updates if full to ensure