Linux-libre 4.7.1-gnupck-4.7.1-gnu

6 files changed, 3611 insertions, 1785 deletions

diff --git a/net/ceph/ceph_common.c b/net/ceph/ceph_common.c
index dcc18c6f7..55d2bfee1 100644
--- a/net/ceph/ceph_common.c
+++ b/net/ceph/ceph_common.c
@@ -651,7 +651,7 @@ EXPORT_SYMBOL(ceph_destroy_client);
 /*
  * true if we have the mon map (and have thus joined the cluster)
  */
-static int have_mon_and_osd_map(struct ceph_client *client)
+static bool have_mon_and_osd_map(struct ceph_client *client)
 {
 	return client->monc.monmap && client->monc.monmap->epoch &&
 	       client->osdc.osdmap && client->osdc.osdmap->epoch;
diff --git a/net/ceph/ceph_strings.c b/net/ceph/ceph_strings.c
index 139a9cb19..3773a4fa1 100644
--- a/net/ceph/ceph_strings.c
+++ b/net/ceph/ceph_strings.c
@@ -27,6 +27,22 @@ __CEPH_FORALL_OSD_OPS(GENERATE_CASE)
 	}
 }
 
+const char *ceph_osd_watch_op_name(int o)
+{
+	switch (o) {
+	case CEPH_OSD_WATCH_OP_UNWATCH:
+		return "unwatch";
+	case CEPH_OSD_WATCH_OP_WATCH:
+		return "watch";
+	case CEPH_OSD_WATCH_OP_RECONNECT:
+		return "reconnect";
+	case CEPH_OSD_WATCH_OP_PING:
+		return "ping";
+	default:
+		return "???";
+	}
+}
+
 const char *ceph_osd_state_name(int s)
 {
 	switch (s) {
diff --git a/net/ceph/debugfs.c b/net/ceph/debugfs.c
index b902fbc78..e77b04ca7 100644
--- a/net/ceph/debugfs.c
+++ b/net/ceph/debugfs.c
@@ -54,24 +54,25 @@ static int osdmap_show(struct seq_file *s, void *p)
 {
 	int i;
 	struct ceph_client *client = s->private;
-	struct ceph_osdmap *map = client->osdc.osdmap;
+	struct ceph_osd_client *osdc = &client->osdc;
+	struct ceph_osdmap *map = osdc->osdmap;
 	struct rb_node *n;
 
 	if (map == NULL)
 		return 0;
 
-	seq_printf(s, "epoch %d\n", map->epoch);
-	seq_printf(s, "flags%s%s\n",
-		   (map->flags & CEPH_OSDMAP_NEARFULL) ?  " NEARFULL" : "",
-		   (map->flags & CEPH_OSDMAP_FULL) ?  " FULL" : "");
+	down_read(&osdc->lock);
+	seq_printf(s, "epoch %d flags 0x%x\n", map->epoch, map->flags);
 
 	for (n = rb_first(&map->pg_pools); n; n = rb_next(n)) {
-		struct ceph_pg_pool_info *pool =
+		struct ceph_pg_pool_info *pi =
 			rb_entry(n, struct ceph_pg_pool_info, node);
 
-		seq_printf(s, "pool %lld pg_num %u (%d) read_tier %lld write_tier %lld\n",
-			   pool->id, pool->pg_num, pool->pg_num_mask,
-			   pool->read_tier, pool->write_tier);
+		seq_printf(s, "pool %lld '%s' type %d size %d min_size %d pg_num %u pg_num_mask %d flags 0x%llx lfor %u read_tier %lld write_tier %lld\n",
+			   pi->id, pi->name, pi->type, pi->size, pi->min_size,
+			   pi->pg_num, pi->pg_num_mask, pi->flags,
+			   pi->last_force_request_resend, pi->read_tier,
+			   pi->write_tier);
 	}
 	for (i = 0; i < map->max_osd; i++) {
 		struct ceph_entity_addr *addr = &map->osd_addr[i];
@@ -103,6 +104,7 @@ static int osdmap_show(struct seq_file *s, void *p)
 			   pg->pgid.seed, pg->primary_temp.osd);
 	}
 
+	up_read(&osdc->lock);
 	return 0;
 }
 
@@ -126,6 +128,7 @@ static int monc_show(struct seq_file *s, void *p)
 					CEPH_SUBSCRIBE_ONETIME ?  "" : "+"));
 		seq_putc(s, '\n');
 	}
+	seq_printf(s, "fs_cluster_id %d\n", monc->fs_cluster_id);
 
 	for (rp = rb_first(&monc->generic_request_tree); rp; rp = rb_next(rp)) {
 		__u16 op;
@@ -143,43 +146,113 @@ static int monc_show(struct seq_file *s, void *p)
 	return 0;
 }
 
-static int osdc_show(struct seq_file *s, void *pp)
+static void dump_target(struct seq_file *s, struct ceph_osd_request_target *t)
 {
-	struct ceph_client *client = s->private;
-	struct ceph_osd_client *osdc = &client->osdc;
-	struct rb_node *p;
+	int i;
 
-	mutex_lock(&osdc->request_mutex);
-	for (p = rb_first(&osdc->requests); p; p = rb_next(p)) {
-		struct ceph_osd_request *req;
-		unsigned int i;
-		int opcode;
+	seq_printf(s, "osd%d\t%llu.%x\t[", t->osd, t->pgid.pool, t->pgid.seed);
+	for (i = 0; i < t->up.size; i++)
+		seq_printf(s, "%s%d", (!i ? "" : ","), t->up.osds[i]);
+	seq_printf(s, "]/%d\t[", t->up.primary);
+	for (i = 0; i < t->acting.size; i++)
+		seq_printf(s, "%s%d", (!i ? "" : ","), t->acting.osds[i]);
+	seq_printf(s, "]/%d\t%*pE\t0x%x", t->acting.primary,
+		   t->target_oid.name_len, t->target_oid.name, t->flags);
+	if (t->paused)
+		seq_puts(s, "\tP");
+}
 
-		req = rb_entry(p, struct ceph_osd_request, r_node);
+static void dump_request(struct seq_file *s, struct ceph_osd_request *req)
+{
+	int i;
 
-		seq_printf(s, "%lld\tosd%d\t%lld.%x\t", req->r_tid,
-			   req->r_osd ? req->r_osd->o_osd : -1,
-			   req->r_pgid.pool, req->r_pgid.seed);
+	seq_printf(s, "%llu\t", req->r_tid);
+	dump_target(s, &req->r_t);
 
-		seq_printf(s, "%.*s", req->r_base_oid.name_len,
-			   req->r_base_oid.name);
+	seq_printf(s, "\t%d\t%u'%llu", req->r_attempts,
+		   le32_to_cpu(req->r_replay_version.epoch),
+		   le64_to_cpu(req->r_replay_version.version));
 
-		if (req->r_reassert_version.epoch)
-			seq_printf(s, "\t%u'%llu",
-			   (unsigned int)le32_to_cpu(req->r_reassert_version.epoch),
-			   le64_to_cpu(req->r_reassert_version.version));
-		else
-			seq_printf(s, "\t");
+	for (i = 0; i < req->r_num_ops; i++) {
+		struct ceph_osd_req_op *op = &req->r_ops[i];
+
+		seq_printf(s, "%s%s", (i == 0 ? "\t" : ","),
+			   ceph_osd_op_name(op->op));
+		if (op->op == CEPH_OSD_OP_WATCH)
+			seq_printf(s, "-%s",
+				   ceph_osd_watch_op_name(op->watch.op));
+	}
+
+	seq_putc(s, '\n');
+}
+
+static void dump_requests(struct seq_file *s, struct ceph_osd *osd)
+{
+	struct rb_node *n;
+
+	mutex_lock(&osd->lock);
+	for (n = rb_first(&osd->o_requests); n; n = rb_next(n)) {
+		struct ceph_osd_request *req =
+		    rb_entry(n, struct ceph_osd_request, r_node);
+
+		dump_request(s, req);
+	}
+
+	mutex_unlock(&osd->lock);
+}
 
-		for (i = 0; i < req->r_num_ops; i++) {
-			opcode = req->r_ops[i].op;
-			seq_printf(s, "%s%s", (i == 0 ? "\t" : ","),
-				   ceph_osd_op_name(opcode));
-		}
+static void dump_linger_request(struct seq_file *s,
+				struct ceph_osd_linger_request *lreq)
+{
+	seq_printf(s, "%llu\t", lreq->linger_id);
+	dump_target(s, &lreq->t);
+
+	seq_printf(s, "\t%u\t%s%s/%d\n", lreq->register_gen,
+		   lreq->is_watch ? "W" : "N", lreq->committed ? "C" : "",
+		   lreq->last_error);
+}
+
+static void dump_linger_requests(struct seq_file *s, struct ceph_osd *osd)
+{
+	struct rb_node *n;
+
+	mutex_lock(&osd->lock);
+	for (n = rb_first(&osd->o_linger_requests); n; n = rb_next(n)) {
+		struct ceph_osd_linger_request *lreq =
+		    rb_entry(n, struct ceph_osd_linger_request, node);
+
+		dump_linger_request(s, lreq);
+	}
+
+	mutex_unlock(&osd->lock);
+}
 
-		seq_printf(s, "\n");
+static int osdc_show(struct seq_file *s, void *pp)
+{
+	struct ceph_client *client = s->private;
+	struct ceph_osd_client *osdc = &client->osdc;
+	struct rb_node *n;
+
+	down_read(&osdc->lock);
+	seq_printf(s, "REQUESTS %d homeless %d\n",
+		   atomic_read(&osdc->num_requests),
+		   atomic_read(&osdc->num_homeless));
+	for (n = rb_first(&osdc->osds); n; n = rb_next(n)) {
+		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
+
+		dump_requests(s, osd);
 	}
-	mutex_unlock(&osdc->request_mutex);
+	dump_requests(s, &osdc->homeless_osd);
+
+	seq_puts(s, "LINGER REQUESTS\n");
+	for (n = rb_first(&osdc->osds); n; n = rb_next(n)) {
+		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
+
+		dump_linger_requests(s, osd);
+	}
+	dump_linger_requests(s, &osdc->homeless_osd);
+
+	up_read(&osdc->lock);
 	return 0;
 }
 
diff --git a/net/ceph/mon_client.c b/net/ceph/mon_client.c
index cf638c009..37c38a7fb 100644
--- a/net/ceph/mon_client.c
+++ b/net/ceph/mon_client.c
@@ -260,20 +260,26 @@ static void __send_subscribe(struct ceph_mon_client *monc)
 	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];
+		char buf[32];
+		int len;
 
 		if (!monc->subs[i].want)
 			continue;
 
-		dout("%s %s start %llu flags 0x%x\n", __func__, s,
+		len = sprintf(buf, "%s", ceph_sub_str[i]);
+		if (i == CEPH_SUB_MDSMAP &&
+		    monc->fs_cluster_id != CEPH_FS_CLUSTER_ID_NONE)
+			len += sprintf(buf + len, ".%d", monc->fs_cluster_id);
+
+		dout("%s %s start %llu flags 0x%x\n", __func__, buf,
 		     le64_to_cpu(monc->subs[i].item.start),
 		     monc->subs[i].item.flags);
-		ceph_encode_string(&p, end, s, strlen(s));
+		ceph_encode_string(&p, end, buf, len);
 		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));
+	BUG_ON(p > end);
 	msg->front.iov_len = p - msg->front.iov_base;
 	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
 	ceph_msg_revoke(msg);
@@ -376,19 +382,13 @@ void ceph_monc_got_map(struct ceph_mon_client *monc, int sub, u32 epoch)
 }
 EXPORT_SYMBOL(ceph_monc_got_map);
 
-/*
- * Register interest in the next osdmap
- */
-void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc)
+void ceph_monc_renew_subs(struct ceph_mon_client *monc)
 {
-	dout("%s have %u\n", __func__, monc->subs[CEPH_SUB_OSDMAP].have);
 	mutex_lock(&monc->mutex);
-	if (__ceph_monc_want_map(monc, CEPH_SUB_OSDMAP,
-				 monc->subs[CEPH_SUB_OSDMAP].have + 1, false))
-		__send_subscribe(monc);
+	__send_subscribe(monc);
 	mutex_unlock(&monc->mutex);
 }
-EXPORT_SYMBOL(ceph_monc_request_next_osdmap);
+EXPORT_SYMBOL(ceph_monc_renew_subs);
 
 /*
  * Wait for an osdmap with a given epoch.
@@ -478,51 +478,17 @@ out:
 /*
  * generic requests (currently statfs, mon_get_version)
  */
-static struct ceph_mon_generic_request *__lookup_generic_req(
-	struct ceph_mon_client *monc, u64 tid)
-{
-	struct ceph_mon_generic_request *req;
-	struct rb_node *n = monc->generic_request_tree.rb_node;
-
-	while (n) {
-		req = rb_entry(n, struct ceph_mon_generic_request, node);
-		if (tid < req->tid)
-			n = n->rb_left;
-		else if (tid > req->tid)
-			n = n->rb_right;
-		else
-			return req;
-	}
-	return NULL;
-}
-
-static void __insert_generic_request(struct ceph_mon_client *monc,
-			    struct ceph_mon_generic_request *new)
-{
-	struct rb_node **p = &monc->generic_request_tree.rb_node;
-	struct rb_node *parent = NULL;
-	struct ceph_mon_generic_request *req = NULL;
-
-	while (*p) {
-		parent = *p;
-		req = rb_entry(parent, struct ceph_mon_generic_request, node);
-		if (new->tid < req->tid)
-			p = &(*p)->rb_left;
-		else if (new->tid > req->tid)
-			p = &(*p)->rb_right;
-		else
-			BUG();
-	}
-
-	rb_link_node(&new->node, parent, p);
-	rb_insert_color(&new->node, &monc->generic_request_tree);
-}
+DEFINE_RB_FUNCS(generic_request, struct ceph_mon_generic_request, tid, node)
 
 static void release_generic_request(struct kref *kref)
 {
 	struct ceph_mon_generic_request *req =
 		container_of(kref, struct ceph_mon_generic_request, kref);
 
+	dout("%s greq %p request %p reply %p\n", __func__, req, req->request,
+	     req->reply);
+	WARN_ON(!RB_EMPTY_NODE(&req->node));
+
 	if (req->reply)
 		ceph_msg_put(req->reply);
 	if (req->request)
@@ -533,7 +499,8 @@ static void release_generic_request(struct kref *kref)
 
 static void put_generic_request(struct ceph_mon_generic_request *req)
 {
-	kref_put(&req->kref, release_generic_request);
+	if (req)
+		kref_put(&req->kref, release_generic_request);
 }
 
 static void get_generic_request(struct ceph_mon_generic_request *req)
@@ -541,6 +508,103 @@ static void get_generic_request(struct ceph_mon_generic_request *req)
 	kref_get(&req->kref);
 }
 
+static struct ceph_mon_generic_request *
+alloc_generic_request(struct ceph_mon_client *monc, gfp_t gfp)
+{
+	struct ceph_mon_generic_request *req;
+
+	req = kzalloc(sizeof(*req), gfp);
+	if (!req)
+		return NULL;
+
+	req->monc = monc;
+	kref_init(&req->kref);
+	RB_CLEAR_NODE(&req->node);
+	init_completion(&req->completion);
+
+	dout("%s greq %p\n", __func__, req);
+	return req;
+}
+
+static void register_generic_request(struct ceph_mon_generic_request *req)
+{
+	struct ceph_mon_client *monc = req->monc;
+
+	WARN_ON(req->tid);
+
+	get_generic_request(req);
+	req->tid = ++monc->last_tid;
+	insert_generic_request(&monc->generic_request_tree, req);
+}
+
+static void send_generic_request(struct ceph_mon_client *monc,
+				 struct ceph_mon_generic_request *req)
+{
+	WARN_ON(!req->tid);
+
+	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
+	req->request->hdr.tid = cpu_to_le64(req->tid);
+	ceph_con_send(&monc->con, ceph_msg_get(req->request));
+}
+
+static void __finish_generic_request(struct ceph_mon_generic_request *req)
+{
+	struct ceph_mon_client *monc = req->monc;
+
+	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
+	erase_generic_request(&monc->generic_request_tree, req);
+
+	ceph_msg_revoke(req->request);
+	ceph_msg_revoke_incoming(req->reply);
+}
+
+static void finish_generic_request(struct ceph_mon_generic_request *req)
+{
+	__finish_generic_request(req);
+	put_generic_request(req);
+}
+
+static void complete_generic_request(struct ceph_mon_generic_request *req)
+{
+	if (req->complete_cb)
+		req->complete_cb(req);
+	else
+		complete_all(&req->completion);
+	put_generic_request(req);
+}
+
+void cancel_generic_request(struct ceph_mon_generic_request *req)
+{
+	struct ceph_mon_client *monc = req->monc;
+	struct ceph_mon_generic_request *lookup_req;
+
+	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
+
+	mutex_lock(&monc->mutex);
+	lookup_req = lookup_generic_request(&monc->generic_request_tree,
+					    req->tid);
+	if (lookup_req) {
+		WARN_ON(lookup_req != req);
+		finish_generic_request(req);
+	}
+
+	mutex_unlock(&monc->mutex);
+}
+
+static int wait_generic_request(struct ceph_mon_generic_request *req)
+{
+	int ret;
+
+	dout("%s greq %p tid %llu\n", __func__, req, req->tid);
+	ret = wait_for_completion_interruptible(&req->completion);
+	if (ret)
+		cancel_generic_request(req);
+	else
+		ret = req->result; /* completed */
+
+	return ret;
+}
+
 static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
 					 struct ceph_msg_header *hdr,
 					 int *skip)
@@ -551,7 +615,7 @@ static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
 	struct ceph_msg *m;
 
 	mutex_lock(&monc->mutex);
-	req = __lookup_generic_req(monc, tid);
+	req = lookup_generic_request(&monc->generic_request_tree, tid);
 	if (!req) {
 		dout("get_generic_reply %lld dne\n", tid);
 		*skip = 1;
@@ -570,42 +634,6 @@ static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
 	return m;
 }
 
-static int __do_generic_request(struct ceph_mon_client *monc, u64 tid,
-				struct ceph_mon_generic_request *req)
-{
-	int err;
-
-	/* register request */
-	req->tid = tid != 0 ? tid : ++monc->last_tid;
-	req->request->hdr.tid = cpu_to_le64(req->tid);
-	__insert_generic_request(monc, req);
-	monc->num_generic_requests++;
-	ceph_con_send(&monc->con, ceph_msg_get(req->request));
-	mutex_unlock(&monc->mutex);
-
-	err = wait_for_completion_interruptible(&req->completion);
-
-	mutex_lock(&monc->mutex);
-	rb_erase(&req->node, &monc->generic_request_tree);
-	monc->num_generic_requests--;
-
-	if (!err)
-		err = req->result;
-	return err;
-}
-
-static int do_generic_request(struct ceph_mon_client *monc,
-			      struct ceph_mon_generic_request *req)
-{
-	int err;
-
-	mutex_lock(&monc->mutex);
-	err = __do_generic_request(monc, 0, req);
-	mutex_unlock(&monc->mutex);
-
-	return err;
-}
-
 /*
  * statfs
  */
@@ -616,22 +644,24 @@ static void handle_statfs_reply(struct ceph_mon_client *monc,
 	struct ceph_mon_statfs_reply *reply = msg->front.iov_base;
 	u64 tid = le64_to_cpu(msg->hdr.tid);
 
+	dout("%s msg %p tid %llu\n", __func__, msg, tid);
+
 	if (msg->front.iov_len != sizeof(*reply))
 		goto bad;
-	dout("handle_statfs_reply %p tid %llu\n", msg, tid);
 
 	mutex_lock(&monc->mutex);
-	req = __lookup_generic_req(monc, tid);
-	if (req) {
-		*(struct ceph_statfs *)req->buf = reply->st;
-		req->result = 0;
-		get_generic_request(req);
+	req = lookup_generic_request(&monc->generic_request_tree, tid);
+	if (!req) {
+		mutex_unlock(&monc->mutex);
+		return;
 	}
+
+	req->result = 0;
+	*req->u.st = reply->st; /* struct */
+	__finish_generic_request(req);
 	mutex_unlock(&monc->mutex);
-	if (req) {
-		complete_all(&req->completion);
-		put_generic_request(req);
-	}
+
+	complete_generic_request(req);
 	return;
 
 bad:
@@ -646,38 +676,38 @@ int ceph_monc_do_statfs(struct ceph_mon_client *monc, struct ceph_statfs *buf)
 {
 	struct ceph_mon_generic_request *req;
 	struct ceph_mon_statfs *h;
-	int err;
+	int ret = -ENOMEM;
 
-	req = kzalloc(sizeof(*req), GFP_NOFS);
+	req = alloc_generic_request(monc, GFP_NOFS);
 	if (!req)
-		return -ENOMEM;
-
-	kref_init(&req->kref);
-	req->buf = buf;
-	init_completion(&req->completion);
+		goto out;
 
-	err = -ENOMEM;
 	req->request = ceph_msg_new(CEPH_MSG_STATFS, sizeof(*h), GFP_NOFS,
 				    true);
 	if (!req->request)
 		goto out;
-	req->reply = ceph_msg_new(CEPH_MSG_STATFS_REPLY, 1024, GFP_NOFS,
-				  true);
+
+	req->reply = ceph_msg_new(CEPH_MSG_STATFS_REPLY, 64, GFP_NOFS, true);
 	if (!req->reply)
 		goto out;
 
+	req->u.st = buf;
+
+	mutex_lock(&monc->mutex);
+	register_generic_request(req);
 	/* fill out request */
 	h = req->request->front.iov_base;
 	h->monhdr.have_version = 0;
 	h->monhdr.session_mon = cpu_to_le16(-1);
 	h->monhdr.session_mon_tid = 0;
 	h->fsid = monc->monmap->fsid;
+	send_generic_request(monc, req);
+	mutex_unlock(&monc->mutex);
 
-	err = do_generic_request(monc, req);
-
+	ret = wait_generic_request(req);
 out:
 	put_generic_request(req);
-	return err;
+	return ret;
 }
 EXPORT_SYMBOL(ceph_monc_do_statfs);
 
@@ -690,7 +720,7 @@ static void handle_get_version_reply(struct ceph_mon_client *monc,
 	void *end = p + msg->front_alloc_len;
 	u64 handle;
 
-	dout("%s %p tid %llu\n", __func__, msg, tid);
+	dout("%s msg %p tid %llu\n", __func__, msg, tid);
 
 	ceph_decode_need(&p, end, 2*sizeof(u64), bad);
 	handle = ceph_decode_64(&p);
@@ -698,77 +728,111 @@ static void handle_get_version_reply(struct ceph_mon_client *monc,
 		goto bad;
 
 	mutex_lock(&monc->mutex);
-	req = __lookup_generic_req(monc, handle);
-	if (req) {
-		*(u64 *)req->buf = ceph_decode_64(&p);
-		req->result = 0;
-		get_generic_request(req);
+	req = lookup_generic_request(&monc->generic_request_tree, handle);
+	if (!req) {
+		mutex_unlock(&monc->mutex);
+		return;
 	}
+
+	req->result = 0;
+	req->u.newest = ceph_decode_64(&p);
+	__finish_generic_request(req);
 	mutex_unlock(&monc->mutex);
-	if (req) {
-		complete_all(&req->completion);
-		put_generic_request(req);
-	}
 
+	complete_generic_request(req);
 	return;
+
 bad:
 	pr_err("corrupt mon_get_version reply, tid %llu\n", tid);
 	ceph_msg_dump(msg);
 }
 
-/*
- * Send MMonGetVersion and wait for the reply.
- *
- * @what: one of "mdsmap", "osdmap" or "monmap"
- */
-int ceph_monc_do_get_version(struct ceph_mon_client *monc, const char *what,
-			     u64 *newest)
+static struct ceph_mon_generic_request *
+__ceph_monc_get_version(struct ceph_mon_client *monc, const char *what,
+			ceph_monc_callback_t cb, u64 private_data)
 {
 	struct ceph_mon_generic_request *req;
-	void *p, *end;
-	u64 tid;
-	int err;
 
-	req = kzalloc(sizeof(*req), GFP_NOFS);
+	req = alloc_generic_request(monc, GFP_NOIO);
 	if (!req)
-		return -ENOMEM;
-
-	kref_init(&req->kref);
-	req->buf = newest;
-	init_completion(&req->completion);
+		goto err_put_req;
 
 	req->request = ceph_msg_new(CEPH_MSG_MON_GET_VERSION,
 				    sizeof(u64) + sizeof(u32) + strlen(what),
-				    GFP_NOFS, true);
-	if (!req->request) {
-		err = -ENOMEM;
-		goto out;
-	}
+				    GFP_NOIO, true);
+	if (!req->request)
+		goto err_put_req;
 
-	req->reply = ceph_msg_new(CEPH_MSG_MON_GET_VERSION_REPLY, 1024,
-				  GFP_NOFS, true);
-	if (!req->reply) {
-		err = -ENOMEM;
-		goto out;
-	}
+	req->reply = ceph_msg_new(CEPH_MSG_MON_GET_VERSION_REPLY, 32, GFP_NOIO,
+				  true);
+	if (!req->reply)
+		goto err_put_req;
 
-	p = req->request->front.iov_base;
-	end = p + req->request->front_alloc_len;
+	req->complete_cb = cb;
+	req->private_data = private_data;
 
-	/* fill out request */
 	mutex_lock(&monc->mutex);
-	tid = ++monc->last_tid;
-	ceph_encode_64(&p, tid); /* handle */
-	ceph_encode_string(&p, end, what, strlen(what));
+	register_generic_request(req);
+	{
+		void *p = req->request->front.iov_base;
+		void *const end = p + req->request->front_alloc_len;
+
+		ceph_encode_64(&p, req->tid); /* handle */
+		ceph_encode_string(&p, end, what, strlen(what));
+		WARN_ON(p != end);
+	}
+	send_generic_request(monc, req);
+	mutex_unlock(&monc->mutex);
 
-	err = __do_generic_request(monc, tid, req);
+	return req;
 
-	mutex_unlock(&monc->mutex);
-out:
+err_put_req:
 	put_generic_request(req);
-	return err;
+	return ERR_PTR(-ENOMEM);
+}
+
+/*
+ * Send MMonGetVersion and wait for the reply.
+ *
+ * @what: one of "mdsmap", "osdmap" or "monmap"
+ */
+int ceph_monc_get_version(struct ceph_mon_client *monc, const char *what,
+			  u64 *newest)
+{
+	struct ceph_mon_generic_request *req;
+	int ret;
+
+	req = __ceph_monc_get_version(monc, what, NULL, 0);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	ret = wait_generic_request(req);
+	if (!ret)
+		*newest = req->u.newest;
+
+	put_generic_request(req);
+	return ret;
 }
-EXPORT_SYMBOL(ceph_monc_do_get_version);
+EXPORT_SYMBOL(ceph_monc_get_version);
+
+/*
+ * Send MMonGetVersion,
+ *
+ * @what: one of "mdsmap", "osdmap" or "monmap"
+ */
+int ceph_monc_get_version_async(struct ceph_mon_client *monc, const char *what,
+				ceph_monc_callback_t cb, u64 private_data)
+{
+	struct ceph_mon_generic_request *req;
+
+	req = __ceph_monc_get_version(monc, what, cb, private_data);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	put_generic_request(req);
+	return 0;
+}
+EXPORT_SYMBOL(ceph_monc_get_version_async);
 
 /*
  * Resend pending generic requests.
@@ -890,7 +954,7 @@ int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
 	if (!monc->m_subscribe_ack)
 		goto out_auth;
 
-	monc->m_subscribe = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 96, GFP_NOFS,
+	monc->m_subscribe = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 128, GFP_NOFS,
 					 true);
 	if (!monc->m_subscribe)
 		goto out_subscribe_ack;
@@ -914,9 +978,10 @@ int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
 
 	INIT_DELAYED_WORK(&monc->delayed_work, delayed_work);
 	monc->generic_request_tree = RB_ROOT;
-	monc->num_generic_requests = 0;
 	monc->last_tid = 0;
 
+	monc->fs_cluster_id = CEPH_FS_CLUSTER_ID_NONE;
+
 	return 0;
 
 out_auth_reply:
@@ -954,6 +1019,8 @@ void ceph_monc_stop(struct ceph_mon_client *monc)
 
 	ceph_auth_destroy(monc->auth);
 
+	WARN_ON(!RB_EMPTY_ROOT(&monc->generic_request_tree));
+
 	ceph_msg_put(monc->m_auth);
 	ceph_msg_put(monc->m_auth_reply);
 	ceph_msg_put(monc->m_subscribe);
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 40a53a70e..894695920 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -19,25 +19,12 @@
 #include <linux/ceph/auth.h>
 #include <linux/ceph/pagelist.h>
 
-#define OSD_OP_FRONT_LEN	4096
 #define OSD_OPREPLY_FRONT_LEN	512
 
 static struct kmem_cache	*ceph_osd_request_cache;
 
 static const struct ceph_connection_operations osd_con_ops;
 
-static void __send_queued(struct ceph_osd_client *osdc);
-static int __reset_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd);
-static void __register_request(struct ceph_osd_client *osdc,
-			       struct ceph_osd_request *req);
-static void __unregister_request(struct ceph_osd_client *osdc,
-				 struct ceph_osd_request *req);
-static void __unregister_linger_request(struct ceph_osd_client *osdc,
-					struct ceph_osd_request *req);
-static void __enqueue_request(struct ceph_osd_request *req);
-static void __send_request(struct ceph_osd_client *osdc,
-			   struct ceph_osd_request *req);
-
 /*
  * Implement client access to distributed object storage cluster.
  *
@@ -56,6 +43,52 @@ static void __send_request(struct ceph_osd_client *osdc,
  * channel with an OSD is reset.
  */
 
+static void link_request(struct ceph_osd *osd, struct ceph_osd_request *req);
+static void unlink_request(struct ceph_osd *osd, struct ceph_osd_request *req);
+static void link_linger(struct ceph_osd *osd,
+			struct ceph_osd_linger_request *lreq);
+static void unlink_linger(struct ceph_osd *osd,
+			  struct ceph_osd_linger_request *lreq);
+
+#if 1
+static inline bool rwsem_is_wrlocked(struct rw_semaphore *sem)
+{
+	bool wrlocked = true;
+
+	if (unlikely(down_read_trylock(sem))) {
+		wrlocked = false;
+		up_read(sem);
+	}
+
+	return wrlocked;
+}
+static inline void verify_osdc_locked(struct ceph_osd_client *osdc)
+{
+	WARN_ON(!rwsem_is_locked(&osdc->lock));
+}
+static inline void verify_osdc_wrlocked(struct ceph_osd_client *osdc)
+{
+	WARN_ON(!rwsem_is_wrlocked(&osdc->lock));
+}
+static inline void verify_osd_locked(struct ceph_osd *osd)
+{
+	struct ceph_osd_client *osdc = osd->o_osdc;
+
+	WARN_ON(!(mutex_is_locked(&osd->lock) &&
+		  rwsem_is_locked(&osdc->lock)) &&
+		!rwsem_is_wrlocked(&osdc->lock));
+}
+static inline void verify_lreq_locked(struct ceph_osd_linger_request *lreq)
+{
+	WARN_ON(!mutex_is_locked(&lreq->lock));
+}
+#else
+static inline void verify_osdc_locked(struct ceph_osd_client *osdc) { }
+static inline void verify_osdc_wrlocked(struct ceph_osd_client *osdc) { }
+static inline void verify_osd_locked(struct ceph_osd *osd) { }
+static inline void verify_lreq_locked(struct ceph_osd_linger_request *lreq) { }
+#endif
+
 /*
  * calculate the mapping of a file extent onto an object, and fill out the
  * request accordingly.  shorten extent as necessary if it crosses an
@@ -144,14 +177,6 @@ osd_req_op_extent_osd_data(struct ceph_osd_request *osd_req,
 }
 EXPORT_SYMBOL(osd_req_op_extent_osd_data);
 
-struct ceph_osd_data *
-osd_req_op_cls_response_data(struct ceph_osd_request *osd_req,
-			unsigned int which)
-{
-	return osd_req_op_data(osd_req, which, cls, response_data);
-}
-EXPORT_SYMBOL(osd_req_op_cls_response_data);	/* ??? */
-
 void osd_req_op_raw_data_in_pages(struct ceph_osd_request *osd_req,
 			unsigned int which, struct page **pages,
 			u64 length, u32 alignment,
@@ -218,6 +243,8 @@ void osd_req_op_cls_request_data_pagelist(
 
 	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
 	ceph_osd_data_pagelist_init(osd_data, pagelist);
+	osd_req->r_ops[which].cls.indata_len += pagelist->length;
+	osd_req->r_ops[which].indata_len += pagelist->length;
 }
 EXPORT_SYMBOL(osd_req_op_cls_request_data_pagelist);
 
@@ -230,6 +257,8 @@ void osd_req_op_cls_request_data_pages(struct ceph_osd_request *osd_req,
 	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
 	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
 				pages_from_pool, own_pages);
+	osd_req->r_ops[which].cls.indata_len += length;
+	osd_req->r_ops[which].indata_len += length;
 }
 EXPORT_SYMBOL(osd_req_op_cls_request_data_pages);
 
@@ -302,14 +331,76 @@ static void osd_req_op_data_release(struct ceph_osd_request *osd_req,
 	case CEPH_OSD_OP_STAT:
 		ceph_osd_data_release(&op->raw_data_in);
 		break;
+	case CEPH_OSD_OP_NOTIFY_ACK:
+		ceph_osd_data_release(&op->notify_ack.request_data);
+		break;
+	case CEPH_OSD_OP_NOTIFY:
+		ceph_osd_data_release(&op->notify.request_data);
+		ceph_osd_data_release(&op->notify.response_data);
+		break;
 	default:
 		break;
 	}
 }
 
 /*
+ * Assumes @t is zero-initialized.
+ */
+static void target_init(struct ceph_osd_request_target *t)
+{
+	ceph_oid_init(&t->base_oid);
+	ceph_oloc_init(&t->base_oloc);
+	ceph_oid_init(&t->target_oid);
+	ceph_oloc_init(&t->target_oloc);
+
+	ceph_osds_init(&t->acting);
+	ceph_osds_init(&t->up);
+	t->size = -1;
+	t->min_size = -1;
+
+	t->osd = CEPH_HOMELESS_OSD;
+}
+
+static void target_copy(struct ceph_osd_request_target *dest,
+			const struct ceph_osd_request_target *src)
+{
+	ceph_oid_copy(&dest->base_oid, &src->base_oid);
+	ceph_oloc_copy(&dest->base_oloc, &src->base_oloc);
+	ceph_oid_copy(&dest->target_oid, &src->target_oid);
+	ceph_oloc_copy(&dest->target_oloc, &src->target_oloc);
+
+	dest->pgid = src->pgid; /* struct */
+	dest->pg_num = src->pg_num;
+	dest->pg_num_mask = src->pg_num_mask;
+	ceph_osds_copy(&dest->acting, &src->acting);
+	ceph_osds_copy(&dest->up, &src->up);
+	dest->size = src->size;
+	dest->min_size = src->min_size;
+	dest->sort_bitwise = src->sort_bitwise;
+
+	dest->flags = src->flags;
+	dest->paused = src->paused;
+
+	dest->osd = src->osd;
+}
+
+static void target_destroy(struct ceph_osd_request_target *t)
+{
+	ceph_oid_destroy(&t->base_oid);
+	ceph_oid_destroy(&t->target_oid);
+}
+
+/*
  * requests
  */
+static void request_release_checks(struct ceph_osd_request *req)
+{
+	WARN_ON(!RB_EMPTY_NODE(&req->r_node));
+	WARN_ON(!RB_EMPTY_NODE(&req->r_mc_node));
+	WARN_ON(!list_empty(&req->r_unsafe_item));
+	WARN_ON(req->r_osd);
+}
+
 static void ceph_osdc_release_request(struct kref *kref)
 {
 	struct ceph_osd_request *req = container_of(kref,
@@ -318,24 +409,19 @@ static void ceph_osdc_release_request(struct kref *kref)
 
 	dout("%s %p (r_request %p r_reply %p)\n", __func__, req,
 	     req->r_request, req->r_reply);
-	WARN_ON(!RB_EMPTY_NODE(&req->r_node));
-	WARN_ON(!list_empty(&req->r_req_lru_item));
-	WARN_ON(!list_empty(&req->r_osd_item));
-	WARN_ON(!list_empty(&req->r_linger_item));
-	WARN_ON(!list_empty(&req->r_linger_osd_item));
-	WARN_ON(req->r_osd);
+	request_release_checks(req);
 
 	if (req->r_request)
 		ceph_msg_put(req->r_request);
-	if (req->r_reply) {
-		ceph_msg_revoke_incoming(req->r_reply);
+	if (req->r_reply)
 		ceph_msg_put(req->r_reply);
-	}
 
 	for (which = 0; which < req->r_num_ops; which++)
 		osd_req_op_data_release(req, which);
 
+	target_destroy(&req->r_t);
 	ceph_put_snap_context(req->r_snapc);
+
 	if (req->r_mempool)
 		mempool_free(req, req->r_osdc->req_mempool);
 	else if (req->r_num_ops <= CEPH_OSD_SLAB_OPS)
@@ -354,12 +440,66 @@ EXPORT_SYMBOL(ceph_osdc_get_request);
 
 void ceph_osdc_put_request(struct ceph_osd_request *req)
 {
-	dout("%s %p (was %d)\n", __func__, req,
-	     atomic_read(&req->r_kref.refcount));
-	kref_put(&req->r_kref, ceph_osdc_release_request);
+	if (req) {
+		dout("%s %p (was %d)\n", __func__, req,
+		     atomic_read(&req->r_kref.refcount));
+		kref_put(&req->r_kref, ceph_osdc_release_request);
+	}
 }
 EXPORT_SYMBOL(ceph_osdc_put_request);
 
+static void request_init(struct ceph_osd_request *req)
+{
+	/* req only, each op is zeroed in _osd_req_op_init() */
+	memset(req, 0, sizeof(*req));
+
+	kref_init(&req->r_kref);
+	init_completion(&req->r_completion);
+	init_completion(&req->r_safe_completion);
+	RB_CLEAR_NODE(&req->r_node);
+	RB_CLEAR_NODE(&req->r_mc_node);
+	INIT_LIST_HEAD(&req->r_unsafe_item);
+
+	target_init(&req->r_t);
+}
+
+/*
+ * This is ugly, but it allows us to reuse linger registration and ping
+ * requests, keeping the structure of the code around send_linger{_ping}()
+ * reasonable.  Setting up a min_nr=2 mempool for each linger request
+ * and dealing with copying ops (this blasts req only, watch op remains
+ * intact) isn't any better.
+ */
+static void request_reinit(struct ceph_osd_request *req)
+{
+	struct ceph_osd_client *osdc = req->r_osdc;
+	bool mempool = req->r_mempool;
+	unsigned int num_ops = req->r_num_ops;
+	u64 snapid = req->r_snapid;
+	struct ceph_snap_context *snapc = req->r_snapc;
+	bool linger = req->r_linger;
+	struct ceph_msg *request_msg = req->r_request;
+	struct ceph_msg *reply_msg = req->r_reply;
+
+	dout("%s req %p\n", __func__, req);
+	WARN_ON(atomic_read(&req->r_kref.refcount) != 1);
+	request_release_checks(req);
+
+	WARN_ON(atomic_read(&request_msg->kref.refcount) != 1);
+	WARN_ON(atomic_read(&reply_msg->kref.refcount) != 1);
+	target_destroy(&req->r_t);
+
+	request_init(req);
+	req->r_osdc = osdc;
+	req->r_mempool = mempool;
+	req->r_num_ops = num_ops;
+	req->r_snapid = snapid;
+	req->r_snapc = snapc;
+	req->r_linger = linger;
+	req->r_request = request_msg;
+	req->r_reply = reply_msg;
+}
+
 struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
 					       struct ceph_snap_context *snapc,
 					       unsigned int num_ops,
@@ -367,8 +507,6 @@ struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
 					       gfp_t gfp_flags)
 {
 	struct ceph_osd_request *req;
-	struct ceph_msg *msg;
-	size_t msg_size;
 
 	if (use_mempool) {
 		BUG_ON(num_ops > CEPH_OSD_SLAB_OPS);
@@ -383,73 +521,65 @@ struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
 	if (unlikely(!req))
 		return NULL;
 
-	/* req only, each op is zeroed in _osd_req_op_init() */
-	memset(req, 0, sizeof(*req));
-
+	request_init(req);
 	req->r_osdc = osdc;
 	req->r_mempool = use_mempool;
 	req->r_num_ops = num_ops;
+	req->r_snapid = CEPH_NOSNAP;
+	req->r_snapc = ceph_get_snap_context(snapc);
 
-	kref_init(&req->r_kref);
-	init_completion(&req->r_completion);
-	init_completion(&req->r_safe_completion);
-	RB_CLEAR_NODE(&req->r_node);
-	INIT_LIST_HEAD(&req->r_unsafe_item);
-	INIT_LIST_HEAD(&req->r_linger_item);
-	INIT_LIST_HEAD(&req->r_linger_osd_item);
-	INIT_LIST_HEAD(&req->r_req_lru_item);
-	INIT_LIST_HEAD(&req->r_osd_item);
-
-	req->r_base_oloc.pool = -1;
-	req->r_target_oloc.pool = -1;
+	dout("%s req %p\n", __func__, req);
+	return req;
+}
+EXPORT_SYMBOL(ceph_osdc_alloc_request);
 
-	msg_size = OSD_OPREPLY_FRONT_LEN;
-	if (num_ops > CEPH_OSD_SLAB_OPS) {
-		/* ceph_osd_op and rval */
-		msg_size += (num_ops - CEPH_OSD_SLAB_OPS) *
-			    (sizeof(struct ceph_osd_op) + 4);
-	}
+int ceph_osdc_alloc_messages(struct ceph_osd_request *req, gfp_t gfp)
+{
+	struct ceph_osd_client *osdc = req->r_osdc;
+	struct ceph_msg *msg;
+	int msg_size;
 
-	/* create reply message */
-	if (use_mempool)
-		msg = ceph_msgpool_get(&osdc->msgpool_op_reply, 0);
-	else
-		msg = ceph_msg_new(CEPH_MSG_OSD_OPREPLY, msg_size,
-				   gfp_flags, true);
-	if (!msg) {
-		ceph_osdc_put_request(req);
-		return NULL;
-	}
-	req->r_reply = msg;
+	WARN_ON(ceph_oid_empty(&req->r_base_oid));
 
+	/* create request message */
 	msg_size = 4 + 4 + 4; /* client_inc, osdmap_epoch, flags */
 	msg_size += 4 + 4 + 4 + 8; /* mtime, reassert_version */
 	msg_size += 2 + 4 + 8 + 4 + 4; /* oloc */
 	msg_size += 1 + 8 + 4 + 4; /* pgid */
-	msg_size += 4 + CEPH_MAX_OID_NAME_LEN; /* oid */
-	msg_size += 2 + num_ops * sizeof(struct ceph_osd_op);
+	msg_size += 4 + req->r_base_oid.name_len; /* oid */
+	msg_size += 2 + req->r_num_ops * sizeof(struct ceph_osd_op);
 	msg_size += 8; /* snapid */
 	msg_size += 8; /* snap_seq */
-	msg_size += 4 + 8 * (snapc ? snapc->num_snaps : 0); /* snaps */
+	msg_size += 4 + 8 * (req->r_snapc ? req->r_snapc->num_snaps : 0);
 	msg_size += 4; /* retry_attempt */
 
-	/* create request message; allow space for oid */
-	if (use_mempool)
+	if (req->r_mempool)
 		msg = ceph_msgpool_get(&osdc->msgpool_op, 0);
 	else
-		msg = ceph_msg_new(CEPH_MSG_OSD_OP, msg_size, gfp_flags, true);
-	if (!msg) {
-		ceph_osdc_put_request(req);
-		return NULL;
-	}
+		msg = ceph_msg_new(CEPH_MSG_OSD_OP, msg_size, gfp, true);
+	if (!msg)
+		return -ENOMEM;
 
 	memset(msg->front.iov_base, 0, msg->front.iov_len);
-
 	req->r_request = msg;
 
-	return req;
+	/* create reply message */
+	msg_size = OSD_OPREPLY_FRONT_LEN;
+	msg_size += req->r_base_oid.name_len;
+	msg_size += req->r_num_ops * sizeof(struct ceph_osd_op);
+
+	if (req->r_mempool)
+		msg = ceph_msgpool_get(&osdc->msgpool_op_reply, 0);
+	else
+		msg = ceph_msg_new(CEPH_MSG_OSD_OPREPLY, msg_size, gfp, true);
+	if (!msg)
+		return -ENOMEM;
+
+	req->r_reply = msg;
+
+	return 0;
 }
-EXPORT_SYMBOL(ceph_osdc_alloc_request);
+EXPORT_SYMBOL(ceph_osdc_alloc_messages);
 
 static bool osd_req_opcode_valid(u16 opcode)
 {
@@ -587,8 +717,6 @@ void osd_req_op_cls_init(struct ceph_osd_request *osd_req, unsigned int which,
 
 	osd_req_op_cls_request_info_pagelist(osd_req, which, pagelist);
 
-	op->cls.argc = 0;	/* currently unused */
-
 	op->indata_len = payload_len;
 }
 EXPORT_SYMBOL(osd_req_op_cls_init);
@@ -627,21 +755,19 @@ int osd_req_op_xattr_init(struct ceph_osd_request *osd_req, unsigned int which,
 }
 EXPORT_SYMBOL(osd_req_op_xattr_init);
 
-void osd_req_op_watch_init(struct ceph_osd_request *osd_req,
-				unsigned int which, u16 opcode,
-				u64 cookie, u64 version, int flag)
+/*
+ * @watch_opcode: CEPH_OSD_WATCH_OP_*
+ */
+static void osd_req_op_watch_init(struct ceph_osd_request *req, int which,
+				  u64 cookie, u8 watch_opcode)
 {
-	struct ceph_osd_req_op *op = _osd_req_op_init(osd_req, which,
-						      opcode, 0);
-
-	BUG_ON(opcode != CEPH_OSD_OP_NOTIFY_ACK && opcode != CEPH_OSD_OP_WATCH);
+	struct ceph_osd_req_op *op;
 
+	op = _osd_req_op_init(req, which, CEPH_OSD_OP_WATCH, 0);
 	op->watch.cookie = cookie;
-	op->watch.ver = version;
-	if (opcode == CEPH_OSD_OP_WATCH && flag)
-		op->watch.flag = (u8)1;
+	op->watch.op = watch_opcode;
+	op->watch.gen = 0;
 }
-EXPORT_SYMBOL(osd_req_op_watch_init);
 
 void osd_req_op_alloc_hint_init(struct ceph_osd_request *osd_req,
 				unsigned int which,
@@ -686,16 +812,9 @@ static void ceph_osdc_msg_data_add(struct ceph_msg *msg,
 	}
 }
 
-static u64 osd_req_encode_op(struct ceph_osd_request *req,
-			      struct ceph_osd_op *dst, unsigned int which)
+static u32 osd_req_encode_op(struct ceph_osd_op *dst,
+			     const struct ceph_osd_req_op *src)
 {
-	struct ceph_osd_req_op *src;
-	struct ceph_osd_data *osd_data;
-	u64 request_data_len = 0;
-	u64 data_length;
-
-	BUG_ON(which >= req->r_num_ops);
-	src = &req->r_ops[which];
 	if (WARN_ON(!osd_req_opcode_valid(src->op))) {
 		pr_err("unrecognized osd opcode %d\n", src->op);
 
@@ -704,57 +823,36 @@ static u64 osd_req_encode_op(struct ceph_osd_request *req,
 
 	switch (src->op) {
 	case CEPH_OSD_OP_STAT:
-		osd_data = &src->raw_data_in;
-		ceph_osdc_msg_data_add(req->r_reply, osd_data);
 		break;
 	case CEPH_OSD_OP_READ:
 	case CEPH_OSD_OP_WRITE:
 	case CEPH_OSD_OP_WRITEFULL:
 	case CEPH_OSD_OP_ZERO:
 	case CEPH_OSD_OP_TRUNCATE:
-		if (src->op == CEPH_OSD_OP_WRITE ||
-		    src->op == CEPH_OSD_OP_WRITEFULL)
-			request_data_len = src->extent.length;
 		dst->extent.offset = cpu_to_le64(src->extent.offset);
 		dst->extent.length = cpu_to_le64(src->extent.length);
 		dst->extent.truncate_size =
 			cpu_to_le64(src->extent.truncate_size);
 		dst->extent.truncate_seq =
 			cpu_to_le32(src->extent.truncate_seq);
-		osd_data = &src->extent.osd_data;
-		if (src->op == CEPH_OSD_OP_WRITE ||
-		    src->op == CEPH_OSD_OP_WRITEFULL)
-			ceph_osdc_msg_data_add(req->r_request, osd_data);
-		else
-			ceph_osdc_msg_data_add(req->r_reply, osd_data);
 		break;
 	case CEPH_OSD_OP_CALL:
 		dst->cls.class_len = src->cls.class_len;
 		dst->cls.method_len = src->cls.method_len;
-		osd_data = &src->cls.request_info;
-		ceph_osdc_msg_data_add(req->r_request, osd_data);
-		BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGELIST);
-		request_data_len = osd_data->pagelist->length;
-
-		osd_data = &src->cls.request_data;
-		data_length = ceph_osd_data_length(osd_data);
-		if (data_length) {
-			BUG_ON(osd_data->type == CEPH_OSD_DATA_TYPE_NONE);
-			dst->cls.indata_len = cpu_to_le32(data_length);
-			ceph_osdc_msg_data_add(req->r_request, osd_data);
-			src->indata_len += data_length;
-			request_data_len += data_length;
-		}
-		osd_data = &src->cls.response_data;
-		ceph_osdc_msg_data_add(req->r_reply, osd_data);
+		dst->cls.indata_len = cpu_to_le32(src->cls.indata_len);
 		break;
 	case CEPH_OSD_OP_STARTSYNC:
 		break;
-	case CEPH_OSD_OP_NOTIFY_ACK:
 	case CEPH_OSD_OP_WATCH:
 		dst->watch.cookie = cpu_to_le64(src->watch.cookie);
-		dst->watch.ver = cpu_to_le64(src->watch.ver);
-		dst->watch.flag = src->watch.flag;
+		dst->watch.ver = cpu_to_le64(0);
+		dst->watch.op = src->watch.op;
+		dst->watch.gen = cpu_to_le32(src->watch.gen);
+		break;
+	case CEPH_OSD_OP_NOTIFY_ACK:
+		break;
+	case CEPH_OSD_OP_NOTIFY:
+		dst->notify.cookie = cpu_to_le64(src->notify.cookie);
 		break;
 	case CEPH_OSD_OP_SETALLOCHINT:
 		dst->alloc_hint.expected_object_size =
@@ -768,9 +866,6 @@ static u64 osd_req_encode_op(struct ceph_osd_request *req,
 		dst->xattr.value_len = cpu_to_le32(src->xattr.value_len);
 		dst->xattr.cmp_op = src->xattr.cmp_op;
 		dst->xattr.cmp_mode = src->xattr.cmp_mode;
-		osd_data = &src->xattr.osd_data;
-		ceph_osdc_msg_data_add(req->r_request, osd_data);
-		request_data_len = osd_data->pagelist->length;
 		break;
 	case CEPH_OSD_OP_CREATE:
 	case CEPH_OSD_OP_DELETE:
@@ -787,7 +882,7 @@ static u64 osd_req_encode_op(struct ceph_osd_request *req,
 	dst->flags = cpu_to_le32(src->flags);
 	dst->payload_len = cpu_to_le32(src->indata_len);
 
-	return request_data_len;
+	return src->indata_len;
 }
 
 /*
@@ -824,17 +919,15 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
 
 	req = ceph_osdc_alloc_request(osdc, snapc, num_ops, use_mempool,
 					GFP_NOFS);
-	if (!req)
-		return ERR_PTR(-ENOMEM);
-
-	req->r_flags = flags;
+	if (!req) {
+		r = -ENOMEM;
+		goto fail;
+	}
 
 	/* calculate max write size */
 	r = calc_layout(layout, off, plen, &objnum, &objoff, &objlen);
-	if (r < 0) {
-		ceph_osdc_put_request(req);
-		return ERR_PTR(r);
-	}
+	if (r)
+		goto fail;
 
 	if (opcode == CEPH_OSD_OP_CREATE || opcode == CEPH_OSD_OP_DELETE) {
 		osd_req_op_init(req, which, opcode, 0);
@@ -854,194 +947,71 @@ struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
 				       truncate_size, truncate_seq);
 	}
 
+	req->r_flags = flags;
 	req->r_base_oloc.pool = ceph_file_layout_pg_pool(*layout);
+	ceph_oid_printf(&req->r_base_oid, "%llx.%08llx", vino.ino, objnum);
+
+	req->r_snapid = vino.snap;
+	if (flags & CEPH_OSD_FLAG_WRITE)
+		req->r_data_offset = off;
 
-	snprintf(req->r_base_oid.name, sizeof(req->r_base_oid.name),
-		 "%llx.%08llx", vino.ino, objnum);
-	req->r_base_oid.name_len = strlen(req->r_base_oid.name);
+	r = ceph_osdc_alloc_messages(req, GFP_NOFS);
+	if (r)
+		goto fail;
 
 	return req;
+
+fail:
+	ceph_osdc_put_request(req);
+	return ERR_PTR(r);
 }
 EXPORT_SYMBOL(ceph_osdc_new_request);
 
 /*
  * We keep osd requests in an rbtree, sorted by ->r_tid.
  */
-static void __insert_request(struct ceph_osd_client *osdc,
-			     struct ceph_osd_request *new)
-{
-	struct rb_node **p = &osdc->requests.rb_node;
-	struct rb_node *parent = NULL;
-	struct ceph_osd_request *req = NULL;
-
-	while (*p) {
-		parent = *p;
-		req = rb_entry(parent, struct ceph_osd_request, r_node);
-		if (new->r_tid < req->r_tid)
-			p = &(*p)->rb_left;
-		else if (new->r_tid > req->r_tid)
-			p = &(*p)->rb_right;
-		else
-			BUG();
-	}
-
-	rb_link_node(&new->r_node, parent, p);
-	rb_insert_color(&new->r_node, &osdc->requests);
-}
+DEFINE_RB_FUNCS(request, struct ceph_osd_request, r_tid, r_node)
+DEFINE_RB_FUNCS(request_mc, struct ceph_osd_request, r_tid, r_mc_node)
 
-static struct ceph_osd_request *__lookup_request(struct ceph_osd_client *osdc,
-						 u64 tid)
+static bool osd_homeless(struct ceph_osd *osd)
 {
-	struct ceph_osd_request *req;
-	struct rb_node *n = osdc->requests.rb_node;
-
-	while (n) {
-		req = rb_entry(n, struct ceph_osd_request, r_node);
-		if (tid < req->r_tid)
-			n = n->rb_left;
-		else if (tid > req->r_tid)
-			n = n->rb_right;
-		else
-			return req;
-	}
-	return NULL;
+	return osd->o_osd == CEPH_HOMELESS_OSD;
 }
 
-static struct ceph_osd_request *
-__lookup_request_ge(struct ceph_osd_client *osdc,
-		    u64 tid)
+static bool osd_registered(struct ceph_osd *osd)
 {
-	struct ceph_osd_request *req;
-	struct rb_node *n = osdc->requests.rb_node;
-
-	while (n) {
-		req = rb_entry(n, struct ceph_osd_request, r_node);
-		if (tid < req->r_tid) {
-			if (!n->rb_left)
-				return req;
-			n = n->rb_left;
-		} else if (tid > req->r_tid) {
-			n = n->rb_right;
-		} else {
-			return req;
-		}
-	}
-	return NULL;
-}
-
-static void __kick_linger_request(struct ceph_osd_request *req)
-{
-	struct ceph_osd_client *osdc = req->r_osdc;
-	struct ceph_osd *osd = req->r_osd;
+	verify_osdc_locked(osd->o_osdc);
 
-	/*
-	 * Linger requests need to be resent with a new tid to avoid
-	 * the dup op detection logic on the OSDs.  Achieve this with
-	 * a re-register dance instead of open-coding.
-	 */
-	ceph_osdc_get_request(req);
-	if (!list_empty(&req->r_linger_item))
-		__unregister_linger_request(osdc, req);
-	else
-		__unregister_request(osdc, req);
-	__register_request(osdc, req);
-	ceph_osdc_put_request(req);
-
-	/*
-	 * Unless request has been registered as both normal and
-	 * lingering, __unregister{,_linger}_request clears r_osd.
-	 * However, here we need to preserve r_osd to make sure we
-	 * requeue on the same OSD.
-	 */
-	WARN_ON(req->r_osd || !osd);
-	req->r_osd = osd;
-
-	dout("%s requeueing %p tid %llu\n", __func__, req, req->r_tid);
-	__enqueue_request(req);
+	return !RB_EMPTY_NODE(&osd->o_node);
 }
 
 /*
- * Resubmit requests pending on the given osd.
+ * Assumes @osd is zero-initialized.
  */
-static void __kick_osd_requests(struct ceph_osd_client *osdc,
-				struct ceph_osd *osd)
+static void osd_init(struct ceph_osd *osd)
 {
-	struct ceph_osd_request *req, *nreq;
-	LIST_HEAD(resend);
-	LIST_HEAD(resend_linger);
-	int err;
-
-	dout("%s osd%d\n", __func__, osd->o_osd);
-	err = __reset_osd(osdc, osd);
-	if (err)
-		return;
-
-	/*
-	 * Build up a list of requests to resend by traversing the
-	 * osd's list of requests.  Requests for a given object are
-	 * sent in tid order, and that is also the order they're
-	 * kept on this list.  Therefore all requests that are in
-	 * flight will be found first, followed by all requests that
-	 * have not yet been sent.  And to resend requests while
-	 * preserving this order we will want to put any sent
-	 * requests back on the front of the osd client's unsent
-	 * list.
-	 *
-	 * So we build a separate ordered list of already-sent
-	 * requests for the affected osd and splice it onto the
-	 * front of the osd client's unsent list.  Once we've seen a
-	 * request that has not yet been sent we're done.  Those
-	 * requests are already sitting right where they belong.
-	 */
-	list_for_each_entry(req, &osd->o_requests, r_osd_item) {
-		if (!req->r_sent)
-			break;
-
-		if (!req->r_linger) {
-			dout("%s requeueing %p tid %llu\n", __func__, req,
-			     req->r_tid);
-			list_move_tail(&req->r_req_lru_item, &resend);
-			req->r_flags |= CEPH_OSD_FLAG_RETRY;
-		} else {
-			list_move_tail(&req->r_req_lru_item, &resend_linger);
-		}
-	}
-	list_splice(&resend, &osdc->req_unsent);
-
-	/*
-	 * Both registered and not yet registered linger requests are
-	 * enqueued with a new tid on the same OSD.  We add/move them
-	 * to req_unsent/o_requests at the end to keep things in tid
-	 * order.
-	 */
-	list_for_each_entry_safe(req, nreq, &osd->o_linger_requests,
-				 r_linger_osd_item) {
-		WARN_ON(!list_empty(&req->r_req_lru_item));
-		__kick_linger_request(req);
-	}
-
-	list_for_each_entry_safe(req, nreq, &resend_linger, r_req_lru_item)
-		__kick_linger_request(req);
+	atomic_set(&osd->o_ref, 1);
+	RB_CLEAR_NODE(&osd->o_node);
+	osd->o_requests = RB_ROOT;
+	osd->o_linger_requests = RB_ROOT;
+	INIT_LIST_HEAD(&osd->o_osd_lru);
+	INIT_LIST_HEAD(&osd->o_keepalive_item);
+	osd->o_incarnation = 1;
+	mutex_init(&osd->lock);
 }
 
-/*
- * If the osd connection drops, we need to resubmit all requests.
- */
-static void osd_reset(struct ceph_connection *con)
+static void osd_cleanup(struct ceph_osd *osd)
 {
-	struct ceph_osd *osd = con->private;
-	struct ceph_osd_client *osdc;
-
-	if (!osd)
-		return;
-	dout("osd_reset osd%d\n", osd->o_osd);
-	osdc = osd->o_osdc;
-	down_read(&osdc->map_sem);
-	mutex_lock(&osdc->request_mutex);
-	__kick_osd_requests(osdc, osd);
-	__send_queued(osdc);
-	mutex_unlock(&osdc->request_mutex);
-	up_read(&osdc->map_sem);
+	WARN_ON(!RB_EMPTY_NODE(&osd->o_node));
+	WARN_ON(!RB_EMPTY_ROOT(&osd->o_requests));
+	WARN_ON(!RB_EMPTY_ROOT(&osd->o_linger_requests));
+	WARN_ON(!list_empty(&osd->o_osd_lru));
+	WARN_ON(!list_empty(&osd->o_keepalive_item));
+
+	if (osd->o_auth.authorizer) {
+		WARN_ON(osd_homeless(osd));
+		ceph_auth_destroy_authorizer(osd->o_auth.authorizer);
+	}
 }
 
 /*
@@ -1051,22 +1021,15 @@ static struct ceph_osd *create_osd(struct ceph_osd_client *osdc, int onum)
 {
 	struct ceph_osd *osd;
 
-	osd = kzalloc(sizeof(*osd), GFP_NOFS);
-	if (!osd)
-		return NULL;
+	WARN_ON(onum == CEPH_HOMELESS_OSD);
 
-	atomic_set(&osd->o_ref, 1);
+	osd = kzalloc(sizeof(*osd), GFP_NOIO | __GFP_NOFAIL);
+	osd_init(osd);
 	osd->o_osdc = osdc;
 	osd->o_osd = onum;
-	RB_CLEAR_NODE(&osd->o_node);
-	INIT_LIST_HEAD(&osd->o_requests);
-	INIT_LIST_HEAD(&osd->o_linger_requests);
-	INIT_LIST_HEAD(&osd->o_osd_lru);
-	osd->o_incarnation = 1;
 
 	ceph_con_init(&osd->o_con, osd, &osd_con_ops, &osdc->client->msgr);
 
-	INIT_LIST_HEAD(&osd->o_keepalive_item);
 	return osd;
 }
 
@@ -1087,114 +1050,115 @@ static void put_osd(struct ceph_osd *osd)
 	dout("put_osd %p %d -> %d\n", osd, atomic_read(&osd->o_ref),
 	     atomic_read(&osd->o_ref) - 1);
 	if (atomic_dec_and_test(&osd->o_ref)) {
-		if (osd->o_auth.authorizer)
-			ceph_auth_destroy_authorizer(osd->o_auth.authorizer);
+		osd_cleanup(osd);
 		kfree(osd);
 	}
 }
 
-/*
- * remove an osd from our map
- */
-static void __remove_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
-{
-	dout("%s %p osd%d\n", __func__, osd, osd->o_osd);
-	WARN_ON(!list_empty(&osd->o_requests));
-	WARN_ON(!list_empty(&osd->o_linger_requests));
-
-	list_del_init(&osd->o_osd_lru);
-	rb_erase(&osd->o_node, &osdc->osds);
-	RB_CLEAR_NODE(&osd->o_node);
-}
-
-static void remove_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
-{
-	dout("%s %p osd%d\n", __func__, osd, osd->o_osd);
-
-	if (!RB_EMPTY_NODE(&osd->o_node)) {
-		ceph_con_close(&osd->o_con);
-		__remove_osd(osdc, osd);
-		put_osd(osd);
-	}
-}
+DEFINE_RB_FUNCS(osd, struct ceph_osd, o_osd, o_node)
 
-static void remove_all_osds(struct ceph_osd_client *osdc)
+static void __move_osd_to_lru(struct ceph_osd *osd)
 {
-	dout("%s %p\n", __func__, osdc);
-	mutex_lock(&osdc->request_mutex);
-	while (!RB_EMPTY_ROOT(&osdc->osds)) {
-		struct ceph_osd *osd = rb_entry(rb_first(&osdc->osds),
-						struct ceph_osd, o_node);
-		remove_osd(osdc, osd);
-	}
-	mutex_unlock(&osdc->request_mutex);
-}
+	struct ceph_osd_client *osdc = osd->o_osdc;
 
-static void __move_osd_to_lru(struct ceph_osd_client *osdc,
-			      struct ceph_osd *osd)
-{
-	dout("%s %p\n", __func__, osd);
+	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
 	BUG_ON(!list_empty(&osd->o_osd_lru));
 
+	spin_lock(&osdc->osd_lru_lock);
 	list_add_tail(&osd->o_osd_lru, &osdc->osd_lru);
+	spin_unlock(&osdc->osd_lru_lock);
+
 	osd->lru_ttl = jiffies + osdc->client->options->osd_idle_ttl;
 }
 
-static void maybe_move_osd_to_lru(struct ceph_osd_client *osdc,
-				  struct ceph_osd *osd)
+static void maybe_move_osd_to_lru(struct ceph_osd *osd)
 {
-	dout("%s %p\n", __func__, osd);
-
-	if (list_empty(&osd->o_requests) &&
-	    list_empty(&osd->o_linger_requests))
-		__move_osd_to_lru(osdc, osd);
+	if (RB_EMPTY_ROOT(&osd->o_requests) &&
+	    RB_EMPTY_ROOT(&osd->o_linger_requests))
+		__move_osd_to_lru(osd);
 }
 
 static void __remove_osd_from_lru(struct ceph_osd *osd)
 {
-	dout("__remove_osd_from_lru %p\n", osd);
+	struct ceph_osd_client *osdc = osd->o_osdc;
+
+	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
+
+	spin_lock(&osdc->osd_lru_lock);
 	if (!list_empty(&osd->o_osd_lru))
 		list_del_init(&osd->o_osd_lru);
+	spin_unlock(&osdc->osd_lru_lock);
 }
 
-static void remove_old_osds(struct ceph_osd_client *osdc)
+/*
+ * Close the connection and assign any leftover requests to the
+ * homeless session.
+ */
+static void close_osd(struct ceph_osd *osd)
 {
-	struct ceph_osd *osd, *nosd;
+	struct ceph_osd_client *osdc = osd->o_osdc;
+	struct rb_node *n;
 
-	dout("__remove_old_osds %p\n", osdc);
-	mutex_lock(&osdc->request_mutex);
-	list_for_each_entry_safe(osd, nosd, &osdc->osd_lru, o_osd_lru) {
-		if (time_before(jiffies, osd->lru_ttl))
-			break;
-		remove_osd(osdc, osd);
+	verify_osdc_wrlocked(osdc);
+	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
+
+	ceph_con_close(&osd->o_con);
+
+	for (n = rb_first(&osd->o_requests); n; ) {
+		struct ceph_osd_request *req =
+		    rb_entry(n, struct ceph_osd_request, r_node);
+
+		n = rb_next(n); /* unlink_request() */
+
+		dout(" reassigning req %p tid %llu\n", req, req->r_tid);
+		unlink_request(osd, req);
+		link_request(&osdc->homeless_osd, req);
+	}
+	for (n = rb_first(&osd->o_linger_requests); n; ) {
+		struct ceph_osd_linger_request *lreq =
+		    rb_entry(n, struct ceph_osd_linger_request, node);
+
+		n = rb_next(n); /* unlink_linger() */
+
+		dout(" reassigning lreq %p linger_id %llu\n", lreq,
+		     lreq->linger_id);
+		unlink_linger(osd, lreq);
+		link_linger(&osdc->homeless_osd, lreq);
 	}
-	mutex_unlock(&osdc->request_mutex);
+
+	__remove_osd_from_lru(osd);
+	erase_osd(&osdc->osds, osd);
+	put_osd(osd);
 }
 
 /*
  * reset osd connect
  */
-static int __reset_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
+static int reopen_osd(struct ceph_osd *osd)
 {
 	struct ceph_entity_addr *peer_addr;
 
-	dout("__reset_osd %p osd%d\n", osd, osd->o_osd);
-	if (list_empty(&osd->o_requests) &&
-	    list_empty(&osd->o_linger_requests)) {
-		remove_osd(osdc, osd);
+	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
+
+	if (RB_EMPTY_ROOT(&osd->o_requests) &&
+	    RB_EMPTY_ROOT(&osd->o_linger_requests)) {
+		close_osd(osd);
 		return -ENODEV;
 	}
 
-	peer_addr = &osdc->osdmap->osd_addr[osd->o_osd];
+	peer_addr = &osd->o_osdc->osdmap->osd_addr[osd->o_osd];
 	if (!memcmp(peer_addr, &osd->o_con.peer_addr, sizeof (*peer_addr)) &&
 			!ceph_con_opened(&osd->o_con)) {
-		struct ceph_osd_request *req;
+		struct rb_node *n;
 
 		dout("osd addr hasn't changed and connection never opened, "
 		     "letting msgr retry\n");
 		/* touch each r_stamp for handle_timeout()'s benfit */
-		list_for_each_entry(req, &osd->o_requests, r_osd_item)
+		for (n = rb_first(&osd->o_requests); n; n = rb_next(n)) {
+			struct ceph_osd_request *req =
+			    rb_entry(n, struct ceph_osd_request, r_node);
 			req->r_stamp = jiffies;
+		}
 
 		return -EAGAIN;
 	}
@@ -1206,455 +1170,1369 @@ static int __reset_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
 	return 0;
 }
 
-static void __insert_osd(struct ceph_osd_client *osdc, struct ceph_osd *new)
+static struct ceph_osd *lookup_create_osd(struct ceph_osd_client *osdc, int o,
+					  bool wrlocked)
 {
-	struct rb_node **p = &osdc->osds.rb_node;
-	struct rb_node *parent = NULL;
-	struct ceph_osd *osd = NULL;
+	struct ceph_osd *osd;
 
-	dout("__insert_osd %p osd%d\n", new, new->o_osd);
-	while (*p) {
-		parent = *p;
-		osd = rb_entry(parent, struct ceph_osd, o_node);
-		if (new->o_osd < osd->o_osd)
-			p = &(*p)->rb_left;
-		else if (new->o_osd > osd->o_osd)
-			p = &(*p)->rb_right;
-		else
-			BUG();
+	if (wrlocked)
+		verify_osdc_wrlocked(osdc);
+	else
+		verify_osdc_locked(osdc);
+
+	if (o != CEPH_HOMELESS_OSD)
+		osd = lookup_osd(&osdc->osds, o);
+	else
+		osd = &osdc->homeless_osd;
+	if (!osd) {
+		if (!wrlocked)
+			return ERR_PTR(-EAGAIN);
+
+		osd = create_osd(osdc, o);
+		insert_osd(&osdc->osds, osd);
+		ceph_con_open(&osd->o_con, CEPH_ENTITY_TYPE_OSD, osd->o_osd,
+			      &osdc->osdmap->osd_addr[osd->o_osd]);
 	}
 
-	rb_link_node(&new->o_node, parent, p);
-	rb_insert_color(&new->o_node, &osdc->osds);
+	dout("%s osdc %p osd%d -> osd %p\n", __func__, osdc, o, osd);
+	return osd;
 }
 
-static struct ceph_osd *__lookup_osd(struct ceph_osd_client *osdc, int o)
+/*
+ * Create request <-> OSD session relation.
+ *
+ * @req has to be assigned a tid, @osd may be homeless.
+ */
+static void link_request(struct ceph_osd *osd, struct ceph_osd_request *req)
 {
-	struct ceph_osd *osd;
-	struct rb_node *n = osdc->osds.rb_node;
-
-	while (n) {
-		osd = rb_entry(n, struct ceph_osd, o_node);
-		if (o < osd->o_osd)
-			n = n->rb_left;
-		else if (o > osd->o_osd)
-			n = n->rb_right;
-		else
-			return osd;
-	}
-	return NULL;
+	verify_osd_locked(osd);
+	WARN_ON(!req->r_tid || req->r_osd);
+	dout("%s osd %p osd%d req %p tid %llu\n", __func__, osd, osd->o_osd,
+	     req, req->r_tid);
+
+	if (!osd_homeless(osd))
+		__remove_osd_from_lru(osd);
+	else
+		atomic_inc(&osd->o_osdc->num_homeless);
+
+	get_osd(osd);
+	insert_request(&osd->o_requests, req);
+	req->r_osd = osd;
 }
 
-static void __schedule_osd_timeout(struct ceph_osd_client *osdc)
+static void unlink_request(struct ceph_osd *osd, struct ceph_osd_request *req)
 {
-	schedule_delayed_work(&osdc->timeout_work,
-			      osdc->client->options->osd_keepalive_timeout);
+	verify_osd_locked(osd);
+	WARN_ON(req->r_osd != osd);
+	dout("%s osd %p osd%d req %p tid %llu\n", __func__, osd, osd->o_osd,
+	     req, req->r_tid);
+
+	req->r_osd = NULL;
+	erase_request(&osd->o_requests, req);
+	put_osd(osd);
+
+	if (!osd_homeless(osd))
+		maybe_move_osd_to_lru(osd);
+	else
+		atomic_dec(&osd->o_osdc->num_homeless);
 }
 
-static void __cancel_osd_timeout(struct ceph_osd_client *osdc)
+static bool __pool_full(struct ceph_pg_pool_info *pi)
 {
-	cancel_delayed_work(&osdc->timeout_work);
+	return pi->flags & CEPH_POOL_FLAG_FULL;
 }
 
-/*
- * Register request, assign tid.  If this is the first request, set up
- * the timeout event.
- */
-static void __register_request(struct ceph_osd_client *osdc,
-			       struct ceph_osd_request *req)
+static bool have_pool_full(struct ceph_osd_client *osdc)
 {
-	req->r_tid = ++osdc->last_tid;
-	req->r_request->hdr.tid = cpu_to_le64(req->r_tid);
-	dout("__register_request %p tid %lld\n", req, req->r_tid);
-	__insert_request(osdc, req);
-	ceph_osdc_get_request(req);
-	osdc->num_requests++;
-	if (osdc->num_requests == 1) {
-		dout(" first request, scheduling timeout\n");
-		__schedule_osd_timeout(osdc);
+	struct rb_node *n;
+
+	for (n = rb_first(&osdc->osdmap->pg_pools); n; n = rb_next(n)) {
+		struct ceph_pg_pool_info *pi =
+		    rb_entry(n, struct ceph_pg_pool_info, node);
+
+		if (__pool_full(pi))
+			return true;
 	}
+
+	return false;
+}
+
+static bool pool_full(struct ceph_osd_client *osdc, s64 pool_id)
+{
+	struct ceph_pg_pool_info *pi;
+
+	pi = ceph_pg_pool_by_id(osdc->osdmap, pool_id);
+	if (!pi)
+		return false;
+
+	return __pool_full(pi);
 }
 
 /*
- * called under osdc->request_mutex
+ * Returns whether a request should be blocked from being sent
+ * based on the current osdmap and osd_client settings.
  */
-static void __unregister_request(struct ceph_osd_client *osdc,
-				 struct ceph_osd_request *req)
+static bool target_should_be_paused(struct ceph_osd_client *osdc,
+				    const struct ceph_osd_request_target *t,
+				    struct ceph_pg_pool_info *pi)
 {
-	if (RB_EMPTY_NODE(&req->r_node)) {
-		dout("__unregister_request %p tid %lld not registered\n",
-			req, req->r_tid);
-		return;
+	bool pauserd = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD);
+	bool pausewr = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR) ||
+		       ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
+		       __pool_full(pi);
+
+	WARN_ON(pi->id != t->base_oloc.pool);
+	return (t->flags & CEPH_OSD_FLAG_READ && pauserd) ||
+	       (t->flags & CEPH_OSD_FLAG_WRITE && pausewr);
+}
+
+enum calc_target_result {
+	CALC_TARGET_NO_ACTION = 0,
+	CALC_TARGET_NEED_RESEND,
+	CALC_TARGET_POOL_DNE,
+};
+
+static enum calc_target_result calc_target(struct ceph_osd_client *osdc,
+					   struct ceph_osd_request_target *t,
+					   u32 *last_force_resend,
+					   bool any_change)
+{
+	struct ceph_pg_pool_info *pi;
+	struct ceph_pg pgid, last_pgid;
+	struct ceph_osds up, acting;
+	bool force_resend = false;
+	bool need_check_tiering = false;
+	bool need_resend = false;
+	bool sort_bitwise = ceph_osdmap_flag(osdc, CEPH_OSDMAP_SORTBITWISE);
+	enum calc_target_result ct_res;
+	int ret;
+
+	pi = ceph_pg_pool_by_id(osdc->osdmap, t->base_oloc.pool);
+	if (!pi) {
+		t->osd = CEPH_HOMELESS_OSD;
+		ct_res = CALC_TARGET_POOL_DNE;
+		goto out;
 	}
 
-	dout("__unregister_request %p tid %lld\n", req, req->r_tid);
-	rb_erase(&req->r_node, &osdc->requests);
-	RB_CLEAR_NODE(&req->r_node);
-	osdc->num_requests--;
+	if (osdc->osdmap->epoch == pi->last_force_request_resend) {
+		if (last_force_resend &&
+		    *last_force_resend < pi->last_force_request_resend) {
+			*last_force_resend = pi->last_force_request_resend;
+			force_resend = true;
+		} else if (!last_force_resend) {
+			force_resend = true;
+		}
+	}
+	if (ceph_oid_empty(&t->target_oid) || force_resend) {
+		ceph_oid_copy(&t->target_oid, &t->base_oid);
+		need_check_tiering = true;
+	}
+	if (ceph_oloc_empty(&t->target_oloc) || force_resend) {
+		ceph_oloc_copy(&t->target_oloc, &t->base_oloc);
+		need_check_tiering = true;
+	}
 
-	if (req->r_osd) {
-		/* make sure the original request isn't in flight. */
-		ceph_msg_revoke(req->r_request);
+	if (need_check_tiering &&
+	    (t->flags & CEPH_OSD_FLAG_IGNORE_OVERLAY) == 0) {
+		if (t->flags & CEPH_OSD_FLAG_READ && pi->read_tier >= 0)
+			t->target_oloc.pool = pi->read_tier;
+		if (t->flags & CEPH_OSD_FLAG_WRITE && pi->write_tier >= 0)
+			t->target_oloc.pool = pi->write_tier;
+	}
 
-		list_del_init(&req->r_osd_item);
-		maybe_move_osd_to_lru(osdc, req->r_osd);
-		if (list_empty(&req->r_linger_osd_item))
-			req->r_osd = NULL;
+	ret = ceph_object_locator_to_pg(osdc->osdmap, &t->target_oid,
+					&t->target_oloc, &pgid);
+	if (ret) {
+		WARN_ON(ret != -ENOENT);
+		t->osd = CEPH_HOMELESS_OSD;
+		ct_res = CALC_TARGET_POOL_DNE;
+		goto out;
+	}
+	last_pgid.pool = pgid.pool;
+	last_pgid.seed = ceph_stable_mod(pgid.seed, t->pg_num, t->pg_num_mask);
+
+	ceph_pg_to_up_acting_osds(osdc->osdmap, &pgid, &up, &acting);
+	if (any_change &&
+	    ceph_is_new_interval(&t->acting,
+				 &acting,
+				 &t->up,
+				 &up,
+				 t->size,
+				 pi->size,
+				 t->min_size,
+				 pi->min_size,
+				 t->pg_num,
+				 pi->pg_num,
+				 t->sort_bitwise,
+				 sort_bitwise,
+				 &last_pgid))
+		force_resend = true;
+
+	if (t->paused && !target_should_be_paused(osdc, t, pi)) {
+		t->paused = false;
+		need_resend = true;
 	}
 
-	list_del_init(&req->r_req_lru_item);
-	ceph_osdc_put_request(req);
+	if (ceph_pg_compare(&t->pgid, &pgid) ||
+	    ceph_osds_changed(&t->acting, &acting, any_change) ||
+	    force_resend) {
+		t->pgid = pgid; /* struct */
+		ceph_osds_copy(&t->acting, &acting);
+		ceph_osds_copy(&t->up, &up);
+		t->size = pi->size;
+		t->min_size = pi->min_size;
+		t->pg_num = pi->pg_num;
+		t->pg_num_mask = pi->pg_num_mask;
+		t->sort_bitwise = sort_bitwise;
+
+		t->osd = acting.primary;
+		need_resend = true;
+	}
+
+	ct_res = need_resend ? CALC_TARGET_NEED_RESEND : CALC_TARGET_NO_ACTION;
+out:
+	dout("%s t %p -> ct_res %d osd %d\n", __func__, t, ct_res, t->osd);
+	return ct_res;
+}
+
+static void setup_request_data(struct ceph_osd_request *req,
+			       struct ceph_msg *msg)
+{
+	u32 data_len = 0;
+	int i;
+
+	if (!list_empty(&msg->data))
+		return;
+
+	WARN_ON(msg->data_length);
+	for (i = 0; i < req->r_num_ops; i++) {
+		struct ceph_osd_req_op *op = &req->r_ops[i];
+
+		switch (op->op) {
+		/* request */
+		case CEPH_OSD_OP_WRITE:
+		case CEPH_OSD_OP_WRITEFULL:
+			WARN_ON(op->indata_len != op->extent.length);
+			ceph_osdc_msg_data_add(msg, &op->extent.osd_data);
+			break;
+		case CEPH_OSD_OP_SETXATTR:
+		case CEPH_OSD_OP_CMPXATTR:
+			WARN_ON(op->indata_len != op->xattr.name_len +
+						  op->xattr.value_len);
+			ceph_osdc_msg_data_add(msg, &op->xattr.osd_data);
+			break;
+		case CEPH_OSD_OP_NOTIFY_ACK:
+			ceph_osdc_msg_data_add(msg,
+					       &op->notify_ack.request_data);
+			break;
+
+		/* reply */
+		case CEPH_OSD_OP_STAT:
+			ceph_osdc_msg_data_add(req->r_reply,
+					       &op->raw_data_in);
+			break;
+		case CEPH_OSD_OP_READ:
+			ceph_osdc_msg_data_add(req->r_reply,
+					       &op->extent.osd_data);
+			break;
+
+		/* both */
+		case CEPH_OSD_OP_CALL:
+			WARN_ON(op->indata_len != op->cls.class_len +
+						  op->cls.method_len +
+						  op->cls.indata_len);
+			ceph_osdc_msg_data_add(msg, &op->cls.request_info);
+			/* optional, can be NONE */
+			ceph_osdc_msg_data_add(msg, &op->cls.request_data);
+			/* optional, can be NONE */
+			ceph_osdc_msg_data_add(req->r_reply,
+					       &op->cls.response_data);
+			break;
+		case CEPH_OSD_OP_NOTIFY:
+			ceph_osdc_msg_data_add(msg,
+					       &op->notify.request_data);
+			ceph_osdc_msg_data_add(req->r_reply,
+					       &op->notify.response_data);
+			break;
+		}
+
+		data_len += op->indata_len;
+	}
+
+	WARN_ON(data_len != msg->data_length);
+}
+
+static void encode_request(struct ceph_osd_request *req, struct ceph_msg *msg)
+{
+	void *p = msg->front.iov_base;
+	void *const end = p + msg->front_alloc_len;
+	u32 data_len = 0;
+	int i;
+
+	if (req->r_flags & CEPH_OSD_FLAG_WRITE) {
+		/* snapshots aren't writeable */
+		WARN_ON(req->r_snapid != CEPH_NOSNAP);
+	} else {
+		WARN_ON(req->r_mtime.tv_sec || req->r_mtime.tv_nsec ||
+			req->r_data_offset || req->r_snapc);
+	}
+
+	setup_request_data(req, msg);
+
+	ceph_encode_32(&p, 1); /* client_inc, always 1 */
+	ceph_encode_32(&p, req->r_osdc->osdmap->epoch);
+	ceph_encode_32(&p, req->r_flags);
+	ceph_encode_timespec(p, &req->r_mtime);
+	p += sizeof(struct ceph_timespec);
+	/* aka reassert_version */
+	memcpy(p, &req->r_replay_version, sizeof(req->r_replay_version));
+	p += sizeof(req->r_replay_version);
+
+	/* oloc */
+	ceph_encode_8(&p, 4);
+	ceph_encode_8(&p, 4);
+	ceph_encode_32(&p, 8 + 4 + 4);
+	ceph_encode_64(&p, req->r_t.target_oloc.pool);
+	ceph_encode_32(&p, -1); /* preferred */
+	ceph_encode_32(&p, 0); /* key len */
+
+	/* pgid */
+	ceph_encode_8(&p, 1);
+	ceph_encode_64(&p, req->r_t.pgid.pool);
+	ceph_encode_32(&p, req->r_t.pgid.seed);
+	ceph_encode_32(&p, -1); /* preferred */
+
+	/* oid */
+	ceph_encode_32(&p, req->r_t.target_oid.name_len);
+	memcpy(p, req->r_t.target_oid.name, req->r_t.target_oid.name_len);
+	p += req->r_t.target_oid.name_len;
 
-	if (osdc->num_requests == 0) {
-		dout(" no requests, canceling timeout\n");
-		__cancel_osd_timeout(osdc);
+	/* ops, can imply data */
+	ceph_encode_16(&p, req->r_num_ops);
+	for (i = 0; i < req->r_num_ops; i++) {
+		data_len += osd_req_encode_op(p, &req->r_ops[i]);
+		p += sizeof(struct ceph_osd_op);
 	}
+
+	ceph_encode_64(&p, req->r_snapid); /* snapid */
+	if (req->r_snapc) {
+		ceph_encode_64(&p, req->r_snapc->seq);
+		ceph_encode_32(&p, req->r_snapc->num_snaps);
+		for (i = 0; i < req->r_snapc->num_snaps; i++)
+			ceph_encode_64(&p, req->r_snapc->snaps[i]);
+	} else {
+		ceph_encode_64(&p, 0); /* snap_seq */
+		ceph_encode_32(&p, 0); /* snaps len */
+	}
+
+	ceph_encode_32(&p, req->r_attempts); /* retry_attempt */
+
+	BUG_ON(p > end);
+	msg->front.iov_len = p - msg->front.iov_base;
+	msg->hdr.version = cpu_to_le16(4); /* MOSDOp v4 */
+	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
+	msg->hdr.data_len = cpu_to_le32(data_len);
+	/*
+	 * The header "data_off" is a hint to the receiver allowing it
+	 * to align received data into its buffers such that there's no
+	 * need to re-copy it before writing it to disk (direct I/O).
+	 */
+	msg->hdr.data_off = cpu_to_le16(req->r_data_offset);
+
+	dout("%s req %p oid %s oid_len %d front %zu data %u\n", __func__,
+	     req, req->r_t.target_oid.name, req->r_t.target_oid.name_len,
+	     msg->front.iov_len, data_len);
 }
 
 /*
- * Cancel a previously queued request message
+ * @req has to be assigned a tid and registered.
  */
-static void __cancel_request(struct ceph_osd_request *req)
+static void send_request(struct ceph_osd_request *req)
 {
-	if (req->r_sent && req->r_osd) {
+	struct ceph_osd *osd = req->r_osd;
+
+	verify_osd_locked(osd);
+	WARN_ON(osd->o_osd != req->r_t.osd);
+
+	/*
+	 * We may have a previously queued request message hanging
+	 * around.  Cancel it to avoid corrupting the msgr.
+	 */
+	if (req->r_sent)
 		ceph_msg_revoke(req->r_request);
-		req->r_sent = 0;
+
+	req->r_flags |= CEPH_OSD_FLAG_KNOWN_REDIR;
+	if (req->r_attempts)
+		req->r_flags |= CEPH_OSD_FLAG_RETRY;
+	else
+		WARN_ON(req->r_flags & CEPH_OSD_FLAG_RETRY);
+
+	encode_request(req, req->r_request);
+
+	dout("%s req %p tid %llu to pg %llu.%x osd%d flags 0x%x attempt %d\n",
+	     __func__, req, req->r_tid, req->r_t.pgid.pool, req->r_t.pgid.seed,
+	     req->r_t.osd, req->r_flags, req->r_attempts);
+
+	req->r_t.paused = false;
+	req->r_stamp = jiffies;
+	req->r_attempts++;
+
+	req->r_sent = osd->o_incarnation;
+	req->r_request->hdr.tid = cpu_to_le64(req->r_tid);
+	ceph_con_send(&osd->o_con, ceph_msg_get(req->r_request));
+}
+
+static void maybe_request_map(struct ceph_osd_client *osdc)
+{
+	bool continuous = false;
+
+	verify_osdc_locked(osdc);
+	WARN_ON(!osdc->osdmap->epoch);
+
+	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
+	    ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD) ||
+	    ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR)) {
+		dout("%s osdc %p continuous\n", __func__, osdc);
+		continuous = true;
+	} else {
+		dout("%s osdc %p onetime\n", __func__, osdc);
 	}
+
+	if (ceph_monc_want_map(&osdc->client->monc, CEPH_SUB_OSDMAP,
+			       osdc->osdmap->epoch + 1, continuous))
+		ceph_monc_renew_subs(&osdc->client->monc);
 }
 
-static void __register_linger_request(struct ceph_osd_client *osdc,
-				    struct ceph_osd_request *req)
+static void send_map_check(struct ceph_osd_request *req);
+
+static void __submit_request(struct ceph_osd_request *req, bool wrlocked)
 {
-	dout("%s %p tid %llu\n", __func__, req, req->r_tid);
-	WARN_ON(!req->r_linger);
+	struct ceph_osd_client *osdc = req->r_osdc;
+	struct ceph_osd *osd;
+	enum calc_target_result ct_res;
+	bool need_send = false;
+	bool promoted = false;
+
+	WARN_ON(req->r_tid || req->r_got_reply);
+	dout("%s req %p wrlocked %d\n", __func__, req, wrlocked);
+
+again:
+	ct_res = calc_target(osdc, &req->r_t, &req->r_last_force_resend, false);
+	if (ct_res == CALC_TARGET_POOL_DNE && !wrlocked)
+		goto promote;
+
+	osd = lookup_create_osd(osdc, req->r_t.osd, wrlocked);
+	if (IS_ERR(osd)) {
+		WARN_ON(PTR_ERR(osd) != -EAGAIN || wrlocked);
+		goto promote;
+	}
+
+	if ((req->r_flags & CEPH_OSD_FLAG_WRITE) &&
+	    ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR)) {
+		dout("req %p pausewr\n", req);
+		req->r_t.paused = true;
+		maybe_request_map(osdc);
+	} else if ((req->r_flags & CEPH_OSD_FLAG_READ) &&
+		   ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD)) {
+		dout("req %p pauserd\n", req);
+		req->r_t.paused = true;
+		maybe_request_map(osdc);
+	} else if ((req->r_flags & CEPH_OSD_FLAG_WRITE) &&
+		   !(req->r_flags & (CEPH_OSD_FLAG_FULL_TRY |
+				     CEPH_OSD_FLAG_FULL_FORCE)) &&
+		   (ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
+		    pool_full(osdc, req->r_t.base_oloc.pool))) {
+		dout("req %p full/pool_full\n", req);
+		pr_warn_ratelimited("FULL or reached pool quota\n");
+		req->r_t.paused = true;
+		maybe_request_map(osdc);
+	} else if (!osd_homeless(osd)) {
+		need_send = true;
+	} else {
+		maybe_request_map(osdc);
+	}
+
+	mutex_lock(&osd->lock);
+	/*
+	 * Assign the tid atomically with send_request() to protect
+	 * multiple writes to the same object from racing with each
+	 * other, resulting in out of order ops on the OSDs.
+	 */
+	req->r_tid = atomic64_inc_return(&osdc->last_tid);
+	link_request(osd, req);
+	if (need_send)
+		send_request(req);
+	mutex_unlock(&osd->lock);
 
+	if (ct_res == CALC_TARGET_POOL_DNE)
+		send_map_check(req);
+
+	if (promoted)
+		downgrade_write(&osdc->lock);
+	return;
+
+promote:
+	up_read(&osdc->lock);
+	down_write(&osdc->lock);
+	wrlocked = true;
+	promoted = true;
+	goto again;
+}
+
+static void account_request(struct ceph_osd_request *req)
+{
+	unsigned int mask = CEPH_OSD_FLAG_ACK | CEPH_OSD_FLAG_ONDISK;
+
+	if (req->r_flags & CEPH_OSD_FLAG_READ) {
+		WARN_ON(req->r_flags & mask);
+		req->r_flags |= CEPH_OSD_FLAG_ACK;
+	} else if (req->r_flags & CEPH_OSD_FLAG_WRITE)
+		WARN_ON(!(req->r_flags & mask));
+	else
+		WARN_ON(1);
+
+	WARN_ON(req->r_unsafe_callback && (req->r_flags & mask) != mask);
+	atomic_inc(&req->r_osdc->num_requests);
+}
+
+static void submit_request(struct ceph_osd_request *req, bool wrlocked)
+{
 	ceph_osdc_get_request(req);
-	list_add_tail(&req->r_linger_item, &osdc->req_linger);
-	if (req->r_osd)
-		list_add_tail(&req->r_linger_osd_item,
-			      &req->r_osd->o_linger_requests);
+	account_request(req);
+	__submit_request(req, wrlocked);
 }
 
-static void __unregister_linger_request(struct ceph_osd_client *osdc,
-					struct ceph_osd_request *req)
+static void __finish_request(struct ceph_osd_request *req)
 {
-	WARN_ON(!req->r_linger);
+	struct ceph_osd_client *osdc = req->r_osdc;
+	struct ceph_osd *osd = req->r_osd;
 
-	if (list_empty(&req->r_linger_item)) {
-		dout("%s %p tid %llu not registered\n", __func__, req,
-		     req->r_tid);
+	verify_osd_locked(osd);
+	dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
+
+	WARN_ON(lookup_request_mc(&osdc->map_checks, req->r_tid));
+	unlink_request(osd, req);
+	atomic_dec(&osdc->num_requests);
+
+	/*
+	 * If an OSD has failed or returned and a request has been sent
+	 * twice, it's possible to get a reply and end up here while the
+	 * request message is queued for delivery.  We will ignore the
+	 * reply, so not a big deal, but better to try and catch it.
+	 */
+	ceph_msg_revoke(req->r_request);
+	ceph_msg_revoke_incoming(req->r_reply);
+}
+
+static void finish_request(struct ceph_osd_request *req)
+{
+	__finish_request(req);
+	ceph_osdc_put_request(req);
+}
+
+static void __complete_request(struct ceph_osd_request *req)
+{
+	if (req->r_callback)
+		req->r_callback(req);
+	else
+		complete_all(&req->r_completion);
+}
+
+/*
+ * Note that this is open-coded in handle_reply(), which has to deal
+ * with ack vs commit, dup acks, etc.
+ */
+static void complete_request(struct ceph_osd_request *req, int err)
+{
+	dout("%s req %p tid %llu err %d\n", __func__, req, req->r_tid, err);
+
+	req->r_result = err;
+	__finish_request(req);
+	__complete_request(req);
+	complete_all(&req->r_safe_completion);
+	ceph_osdc_put_request(req);
+}
+
+static void cancel_map_check(struct ceph_osd_request *req)
+{
+	struct ceph_osd_client *osdc = req->r_osdc;
+	struct ceph_osd_request *lookup_req;
+
+	verify_osdc_wrlocked(osdc);
+
+	lookup_req = lookup_request_mc(&osdc->map_checks, req->r_tid);
+	if (!lookup_req)
 		return;
+
+	WARN_ON(lookup_req != req);
+	erase_request_mc(&osdc->map_checks, req);
+	ceph_osdc_put_request(req);
+}
+
+static void cancel_request(struct ceph_osd_request *req)
+{
+	dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
+
+	cancel_map_check(req);
+	finish_request(req);
+}
+
+static void check_pool_dne(struct ceph_osd_request *req)
+{
+	struct ceph_osd_client *osdc = req->r_osdc;
+	struct ceph_osdmap *map = osdc->osdmap;
+
+	verify_osdc_wrlocked(osdc);
+	WARN_ON(!map->epoch);
+
+	if (req->r_attempts) {
+		/*
+		 * We sent a request earlier, which means that
+		 * previously the pool existed, and now it does not
+		 * (i.e., it was deleted).
+		 */
+		req->r_map_dne_bound = map->epoch;
+		dout("%s req %p tid %llu pool disappeared\n", __func__, req,
+		     req->r_tid);
+	} else {
+		dout("%s req %p tid %llu map_dne_bound %u have %u\n", __func__,
+		     req, req->r_tid, req->r_map_dne_bound, map->epoch);
+	}
+
+	if (req->r_map_dne_bound) {
+		if (map->epoch >= req->r_map_dne_bound) {
+			/* we had a new enough map */
+			pr_info_ratelimited("tid %llu pool does not exist\n",
+					    req->r_tid);
+			complete_request(req, -ENOENT);
+		}
+	} else {
+		send_map_check(req);
 	}
+}
+
+static void map_check_cb(struct ceph_mon_generic_request *greq)
+{
+	struct ceph_osd_client *osdc = &greq->monc->client->osdc;
+	struct ceph_osd_request *req;
+	u64 tid = greq->private_data;
 
-	dout("%s %p tid %llu\n", __func__, req, req->r_tid);
-	list_del_init(&req->r_linger_item);
+	WARN_ON(greq->result || !greq->u.newest);
 
-	if (req->r_osd) {
-		list_del_init(&req->r_linger_osd_item);
-		maybe_move_osd_to_lru(osdc, req->r_osd);
-		if (list_empty(&req->r_osd_item))
-			req->r_osd = NULL;
+	down_write(&osdc->lock);
+	req = lookup_request_mc(&osdc->map_checks, tid);
+	if (!req) {
+		dout("%s tid %llu dne\n", __func__, tid);
+		goto out_unlock;
 	}
+
+	dout("%s req %p tid %llu map_dne_bound %u newest %llu\n", __func__,
+	     req, req->r_tid, req->r_map_dne_bound, greq->u.newest);
+	if (!req->r_map_dne_bound)
+		req->r_map_dne_bound = greq->u.newest;
+	erase_request_mc(&osdc->map_checks, req);
+	check_pool_dne(req);
+
 	ceph_osdc_put_request(req);
+out_unlock:
+	up_write(&osdc->lock);
 }
 
-void ceph_osdc_set_request_linger(struct ceph_osd_client *osdc,
-				  struct ceph_osd_request *req)
+static void send_map_check(struct ceph_osd_request *req)
 {
-	if (!req->r_linger) {
-		dout("set_request_linger %p\n", req);
-		req->r_linger = 1;
+	struct ceph_osd_client *osdc = req->r_osdc;
+	struct ceph_osd_request *lookup_req;
+	int ret;
+
+	verify_osdc_wrlocked(osdc);
+
+	lookup_req = lookup_request_mc(&osdc->map_checks, req->r_tid);
+	if (lookup_req) {
+		WARN_ON(lookup_req != req);
+		return;
 	}
+
+	ceph_osdc_get_request(req);
+	insert_request_mc(&osdc->map_checks, req);
+	ret = ceph_monc_get_version_async(&osdc->client->monc, "osdmap",
+					  map_check_cb, req->r_tid);
+	WARN_ON(ret);
 }
-EXPORT_SYMBOL(ceph_osdc_set_request_linger);
 
 /*
- * Returns whether a request should be blocked from being sent
- * based on the current osdmap and osd_client settings.
- *
- * Caller should hold map_sem for read.
+ * lingering requests, watch/notify v2 infrastructure
  */
-static bool __req_should_be_paused(struct ceph_osd_client *osdc,
-				   struct ceph_osd_request *req)
+static void linger_release(struct kref *kref)
+{
+	struct ceph_osd_linger_request *lreq =
+	    container_of(kref, struct ceph_osd_linger_request, kref);
+
+	dout("%s lreq %p reg_req %p ping_req %p\n", __func__, lreq,
+	     lreq->reg_req, lreq->ping_req);
+	WARN_ON(!RB_EMPTY_NODE(&lreq->node));
+	WARN_ON(!RB_EMPTY_NODE(&lreq->osdc_node));
+	WARN_ON(!RB_EMPTY_NODE(&lreq->mc_node));
+	WARN_ON(!list_empty(&lreq->scan_item));
+	WARN_ON(!list_empty(&lreq->pending_lworks));
+	WARN_ON(lreq->osd);
+
+	if (lreq->reg_req)
+		ceph_osdc_put_request(lreq->reg_req);
+	if (lreq->ping_req)
+		ceph_osdc_put_request(lreq->ping_req);
+	target_destroy(&lreq->t);
+	kfree(lreq);
+}
+
+static void linger_put(struct ceph_osd_linger_request *lreq)
 {
-	bool pauserd = ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_PAUSERD);
-	bool pausewr = ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_PAUSEWR) ||
-		ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL);
-	return (req->r_flags & CEPH_OSD_FLAG_READ && pauserd) ||
-		(req->r_flags & CEPH_OSD_FLAG_WRITE && pausewr);
+	if (lreq)
+		kref_put(&lreq->kref, linger_release);
+}
+
+static struct ceph_osd_linger_request *
+linger_get(struct ceph_osd_linger_request *lreq)
+{
+	kref_get(&lreq->kref);
+	return lreq;
+}
+
+static struct ceph_osd_linger_request *
+linger_alloc(struct ceph_osd_client *osdc)
+{
+	struct ceph_osd_linger_request *lreq;
+
+	lreq = kzalloc(sizeof(*lreq), GFP_NOIO);
+	if (!lreq)
+		return NULL;
+
+	kref_init(&lreq->kref);
+	mutex_init(&lreq->lock);
+	RB_CLEAR_NODE(&lreq->node);
+	RB_CLEAR_NODE(&lreq->osdc_node);
+	RB_CLEAR_NODE(&lreq->mc_node);
+	INIT_LIST_HEAD(&lreq->scan_item);
+	INIT_LIST_HEAD(&lreq->pending_lworks);
+	init_completion(&lreq->reg_commit_wait);
+	init_completion(&lreq->notify_finish_wait);
+
+	lreq->osdc = osdc;
+	target_init(&lreq->t);
+
+	dout("%s lreq %p\n", __func__, lreq);
+	return lreq;
 }
 
+DEFINE_RB_INSDEL_FUNCS(linger, struct ceph_osd_linger_request, linger_id, node)
+DEFINE_RB_FUNCS(linger_osdc, struct ceph_osd_linger_request, linger_id, osdc_node)
+DEFINE_RB_FUNCS(linger_mc, struct ceph_osd_linger_request, linger_id, mc_node)
+
 /*
- * Calculate mapping of a request to a PG.  Takes tiering into account.
+ * Create linger request <-> OSD session relation.
+ *
+ * @lreq has to be registered, @osd may be homeless.
  */
-static int __calc_request_pg(struct ceph_osdmap *osdmap,
-			     struct ceph_osd_request *req,
-			     struct ceph_pg *pg_out)
+static void link_linger(struct ceph_osd *osd,
+			struct ceph_osd_linger_request *lreq)
 {
-	bool need_check_tiering;
+	verify_osd_locked(osd);
+	WARN_ON(!lreq->linger_id || lreq->osd);
+	dout("%s osd %p osd%d lreq %p linger_id %llu\n", __func__, osd,
+	     osd->o_osd, lreq, lreq->linger_id);
 
-	need_check_tiering = false;
-	if (req->r_target_oloc.pool == -1) {
-		req->r_target_oloc = req->r_base_oloc; /* struct */
-		need_check_tiering = true;
+	if (!osd_homeless(osd))
+		__remove_osd_from_lru(osd);
+	else
+		atomic_inc(&osd->o_osdc->num_homeless);
+
+	get_osd(osd);
+	insert_linger(&osd->o_linger_requests, lreq);
+	lreq->osd = osd;
+}
+
+static void unlink_linger(struct ceph_osd *osd,
+			  struct ceph_osd_linger_request *lreq)
+{
+	verify_osd_locked(osd);
+	WARN_ON(lreq->osd != osd);
+	dout("%s osd %p osd%d lreq %p linger_id %llu\n", __func__, osd,
+	     osd->o_osd, lreq, lreq->linger_id);
+
+	lreq->osd = NULL;
+	erase_linger(&osd->o_linger_requests, lreq);
+	put_osd(osd);
+
+	if (!osd_homeless(osd))
+		maybe_move_osd_to_lru(osd);
+	else
+		atomic_dec(&osd->o_osdc->num_homeless);
+}
+
+static bool __linger_registered(struct ceph_osd_linger_request *lreq)
+{
+	verify_osdc_locked(lreq->osdc);
+
+	return !RB_EMPTY_NODE(&lreq->osdc_node);
+}
+
+static bool linger_registered(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
+	bool registered;
+
+	down_read(&osdc->lock);
+	registered = __linger_registered(lreq);
+	up_read(&osdc->lock);
+
+	return registered;
+}
+
+static void linger_register(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
+
+	verify_osdc_wrlocked(osdc);
+	WARN_ON(lreq->linger_id);
+
+	linger_get(lreq);
+	lreq->linger_id = ++osdc->last_linger_id;
+	insert_linger_osdc(&osdc->linger_requests, lreq);
+}
+
+static void linger_unregister(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
+
+	verify_osdc_wrlocked(osdc);
+
+	erase_linger_osdc(&osdc->linger_requests, lreq);
+	linger_put(lreq);
+}
+
+static void cancel_linger_request(struct ceph_osd_request *req)
+{
+	struct ceph_osd_linger_request *lreq = req->r_priv;
+
+	WARN_ON(!req->r_linger);
+	cancel_request(req);
+	linger_put(lreq);
+}
+
+struct linger_work {
+	struct work_struct work;
+	struct ceph_osd_linger_request *lreq;
+	struct list_head pending_item;
+	unsigned long queued_stamp;
+
+	union {
+		struct {
+			u64 notify_id;
+			u64 notifier_id;
+			void *payload; /* points into @msg front */
+			size_t payload_len;
+
+			struct ceph_msg *msg; /* for ceph_msg_put() */
+		} notify;
+		struct {
+			int err;
+		} error;
+	};
+};
+
+static struct linger_work *lwork_alloc(struct ceph_osd_linger_request *lreq,
+				       work_func_t workfn)
+{
+	struct linger_work *lwork;
+
+	lwork = kzalloc(sizeof(*lwork), GFP_NOIO);
+	if (!lwork)
+		return NULL;
+
+	INIT_WORK(&lwork->work, workfn);
+	INIT_LIST_HEAD(&lwork->pending_item);
+	lwork->lreq = linger_get(lreq);
+
+	return lwork;
+}
+
+static void lwork_free(struct linger_work *lwork)
+{
+	struct ceph_osd_linger_request *lreq = lwork->lreq;
+
+	mutex_lock(&lreq->lock);
+	list_del(&lwork->pending_item);
+	mutex_unlock(&lreq->lock);
+
+	linger_put(lreq);
+	kfree(lwork);
+}
+
+static void lwork_queue(struct linger_work *lwork)
+{
+	struct ceph_osd_linger_request *lreq = lwork->lreq;
+	struct ceph_osd_client *osdc = lreq->osdc;
+
+	verify_lreq_locked(lreq);
+	WARN_ON(!list_empty(&lwork->pending_item));
+
+	lwork->queued_stamp = jiffies;
+	list_add_tail(&lwork->pending_item, &lreq->pending_lworks);
+	queue_work(osdc->notify_wq, &lwork->work);
+}
+
+static void do_watch_notify(struct work_struct *w)
+{
+	struct linger_work *lwork = container_of(w, struct linger_work, work);
+	struct ceph_osd_linger_request *lreq = lwork->lreq;
+
+	if (!linger_registered(lreq)) {
+		dout("%s lreq %p not registered\n", __func__, lreq);
+		goto out;
 	}
-	if (req->r_target_oid.name_len == 0) {
-		ceph_oid_copy(&req->r_target_oid, &req->r_base_oid);
-		need_check_tiering = true;
+
+	WARN_ON(!lreq->is_watch);
+	dout("%s lreq %p notify_id %llu notifier_id %llu payload_len %zu\n",
+	     __func__, lreq, lwork->notify.notify_id, lwork->notify.notifier_id,
+	     lwork->notify.payload_len);
+	lreq->wcb(lreq->data, lwork->notify.notify_id, lreq->linger_id,
+		  lwork->notify.notifier_id, lwork->notify.payload,
+		  lwork->notify.payload_len);
+
+out:
+	ceph_msg_put(lwork->notify.msg);
+	lwork_free(lwork);
+}
+
+static void do_watch_error(struct work_struct *w)
+{
+	struct linger_work *lwork = container_of(w, struct linger_work, work);
+	struct ceph_osd_linger_request *lreq = lwork->lreq;
+
+	if (!linger_registered(lreq)) {
+		dout("%s lreq %p not registered\n", __func__, lreq);
+		goto out;
 	}
 
-	if (need_check_tiering &&
-	    (req->r_flags & CEPH_OSD_FLAG_IGNORE_OVERLAY) == 0) {
-		struct ceph_pg_pool_info *pi;
-
-		pi = ceph_pg_pool_by_id(osdmap, req->r_target_oloc.pool);
-		if (pi) {
-			if ((req->r_flags & CEPH_OSD_FLAG_READ) &&
-			    pi->read_tier >= 0)
-				req->r_target_oloc.pool = pi->read_tier;
-			if ((req->r_flags & CEPH_OSD_FLAG_WRITE) &&
-			    pi->write_tier >= 0)
-				req->r_target_oloc.pool = pi->write_tier;
+	dout("%s lreq %p err %d\n", __func__, lreq, lwork->error.err);
+	lreq->errcb(lreq->data, lreq->linger_id, lwork->error.err);
+
+out:
+	lwork_free(lwork);
+}
+
+static void queue_watch_error(struct ceph_osd_linger_request *lreq)
+{
+	struct linger_work *lwork;
+
+	lwork = lwork_alloc(lreq, do_watch_error);
+	if (!lwork) {
+		pr_err("failed to allocate error-lwork\n");
+		return;
+	}
+
+	lwork->error.err = lreq->last_error;
+	lwork_queue(lwork);
+}
+
+static void linger_reg_commit_complete(struct ceph_osd_linger_request *lreq,
+				       int result)
+{
+	if (!completion_done(&lreq->reg_commit_wait)) {
+		lreq->reg_commit_error = (result <= 0 ? result : 0);
+		complete_all(&lreq->reg_commit_wait);
+	}
+}
+
+static void linger_commit_cb(struct ceph_osd_request *req)
+{
+	struct ceph_osd_linger_request *lreq = req->r_priv;
+
+	mutex_lock(&lreq->lock);
+	dout("%s lreq %p linger_id %llu result %d\n", __func__, lreq,
+	     lreq->linger_id, req->r_result);
+	WARN_ON(!__linger_registered(lreq));
+	linger_reg_commit_complete(lreq, req->r_result);
+	lreq->committed = true;
+
+	if (!lreq->is_watch) {
+		struct ceph_osd_data *osd_data =
+		    osd_req_op_data(req, 0, notify, response_data);
+		void *p = page_address(osd_data->pages[0]);
+
+		WARN_ON(req->r_ops[0].op != CEPH_OSD_OP_NOTIFY ||
+			osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+
+		/* make note of the notify_id */
+		if (req->r_ops[0].outdata_len >= sizeof(u64)) {
+			lreq->notify_id = ceph_decode_64(&p);
+			dout("lreq %p notify_id %llu\n", lreq,
+			     lreq->notify_id);
+		} else {
+			dout("lreq %p no notify_id\n", lreq);
 		}
-		/* !pi is caught in ceph_oloc_oid_to_pg() */
 	}
 
-	return ceph_oloc_oid_to_pg(osdmap, &req->r_target_oloc,
-				   &req->r_target_oid, pg_out);
+	mutex_unlock(&lreq->lock);
+	linger_put(lreq);
 }
 
-static void __enqueue_request(struct ceph_osd_request *req)
+static int normalize_watch_error(int err)
 {
-	struct ceph_osd_client *osdc = req->r_osdc;
+	/*
+	 * Translate ENOENT -> ENOTCONN so that a delete->disconnection
+	 * notification and a failure to reconnect because we raced with
+	 * the delete appear the same to the user.
+	 */
+	if (err == -ENOENT)
+		err = -ENOTCONN;
+
+	return err;
+}
+
+static void linger_reconnect_cb(struct ceph_osd_request *req)
+{
+	struct ceph_osd_linger_request *lreq = req->r_priv;
+
+	mutex_lock(&lreq->lock);
+	dout("%s lreq %p linger_id %llu result %d last_error %d\n", __func__,
+	     lreq, lreq->linger_id, req->r_result, lreq->last_error);
+	if (req->r_result < 0) {
+		if (!lreq->last_error) {
+			lreq->last_error = normalize_watch_error(req->r_result);
+			queue_watch_error(lreq);
+		}
+	}
+
+	mutex_unlock(&lreq->lock);
+	linger_put(lreq);
+}
+
+static void send_linger(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_request *req = lreq->reg_req;
+	struct ceph_osd_req_op *op = &req->r_ops[0];
 
-	dout("%s %p tid %llu to osd%d\n", __func__, req, req->r_tid,
-	     req->r_osd ? req->r_osd->o_osd : -1);
+	verify_osdc_wrlocked(req->r_osdc);
+	dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
 
-	if (req->r_osd) {
-		__remove_osd_from_lru(req->r_osd);
-		list_add_tail(&req->r_osd_item, &req->r_osd->o_requests);
-		list_move_tail(&req->r_req_lru_item, &osdc->req_unsent);
+	if (req->r_osd)
+		cancel_linger_request(req);
+
+	request_reinit(req);
+	ceph_oid_copy(&req->r_base_oid, &lreq->t.base_oid);
+	ceph_oloc_copy(&req->r_base_oloc, &lreq->t.base_oloc);
+	req->r_flags = lreq->t.flags;
+	req->r_mtime = lreq->mtime;
+
+	mutex_lock(&lreq->lock);
+	if (lreq->is_watch && lreq->committed) {
+		WARN_ON(op->op != CEPH_OSD_OP_WATCH ||
+			op->watch.cookie != lreq->linger_id);
+		op->watch.op = CEPH_OSD_WATCH_OP_RECONNECT;
+		op->watch.gen = ++lreq->register_gen;
+		dout("lreq %p reconnect register_gen %u\n", lreq,
+		     op->watch.gen);
+		req->r_callback = linger_reconnect_cb;
 	} else {
-		list_move_tail(&req->r_req_lru_item, &osdc->req_notarget);
+		if (!lreq->is_watch)
+			lreq->notify_id = 0;
+		else
+			WARN_ON(op->watch.op != CEPH_OSD_WATCH_OP_WATCH);
+		dout("lreq %p register\n", lreq);
+		req->r_callback = linger_commit_cb;
 	}
+	mutex_unlock(&lreq->lock);
+
+	req->r_priv = linger_get(lreq);
+	req->r_linger = true;
+
+	submit_request(req, true);
 }
 
-/*
- * Pick an osd (the first 'up' osd in the pg), allocate the osd struct
- * (as needed), and set the request r_osd appropriately.  If there is
- * no up osd, set r_osd to NULL.  Move the request to the appropriate list
- * (unsent, homeless) or leave on in-flight lru.
- *
- * Return 0 if unchanged, 1 if changed, or negative on error.
- *
- * Caller should hold map_sem for read and request_mutex.
- */
-static int __map_request(struct ceph_osd_client *osdc,
-			 struct ceph_osd_request *req, int force_resend)
+static void linger_ping_cb(struct ceph_osd_request *req)
 {
-	struct ceph_pg pgid;
-	int acting[CEPH_PG_MAX_SIZE];
-	int num, o;
-	int err;
-	bool was_paused;
-
-	dout("map_request %p tid %lld\n", req, req->r_tid);
-
-	err = __calc_request_pg(osdc->osdmap, req, &pgid);
-	if (err) {
-		list_move(&req->r_req_lru_item, &osdc->req_notarget);
-		return err;
-	}
-	req->r_pgid = pgid;
-
-	num = ceph_calc_pg_acting(osdc->osdmap, pgid, acting, &o);
-	if (num < 0)
-		num = 0;
-
-	was_paused = req->r_paused;
-	req->r_paused = __req_should_be_paused(osdc, req);
-	if (was_paused && !req->r_paused)
-		force_resend = 1;
-
-	if ((!force_resend &&
-	     req->r_osd && req->r_osd->o_osd == o &&
-	     req->r_sent >= req->r_osd->o_incarnation &&
-	     req->r_num_pg_osds == num &&
-	     memcmp(req->r_pg_osds, acting, sizeof(acting[0])*num) == 0) ||
-	    (req->r_osd == NULL && o == -1) ||
-	    req->r_paused)
-		return 0;  /* no change */
-
-	dout("map_request tid %llu pgid %lld.%x osd%d (was osd%d)\n",
-	     req->r_tid, pgid.pool, pgid.seed, o,
-	     req->r_osd ? req->r_osd->o_osd : -1);
-
-	/* record full pg acting set */
-	memcpy(req->r_pg_osds, acting, sizeof(acting[0]) * num);
-	req->r_num_pg_osds = num;
-
-	if (req->r_osd) {
-		__cancel_request(req);
-		list_del_init(&req->r_osd_item);
-		list_del_init(&req->r_linger_osd_item);
-		req->r_osd = NULL;
-	}
-
-	req->r_osd = __lookup_osd(osdc, o);
-	if (!req->r_osd && o >= 0) {
-		err = -ENOMEM;
-		req->r_osd = create_osd(osdc, o);
-		if (!req->r_osd) {
-			list_move(&req->r_req_lru_item, &osdc->req_notarget);
-			goto out;
+	struct ceph_osd_linger_request *lreq = req->r_priv;
+
+	mutex_lock(&lreq->lock);
+	dout("%s lreq %p linger_id %llu result %d ping_sent %lu last_error %d\n",
+	     __func__, lreq, lreq->linger_id, req->r_result, lreq->ping_sent,
+	     lreq->last_error);
+	if (lreq->register_gen == req->r_ops[0].watch.gen) {
+		if (!req->r_result) {
+			lreq->watch_valid_thru = lreq->ping_sent;
+		} else if (!lreq->last_error) {
+			lreq->last_error = normalize_watch_error(req->r_result);
+			queue_watch_error(lreq);
 		}
+	} else {
+		dout("lreq %p register_gen %u ignoring old pong %u\n", lreq,
+		     lreq->register_gen, req->r_ops[0].watch.gen);
+	}
+
+	mutex_unlock(&lreq->lock);
+	linger_put(lreq);
+}
 
-		dout("map_request osd %p is osd%d\n", req->r_osd, o);
-		__insert_osd(osdc, req->r_osd);
+static void send_linger_ping(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
+	struct ceph_osd_request *req = lreq->ping_req;
+	struct ceph_osd_req_op *op = &req->r_ops[0];
 
-		ceph_con_open(&req->r_osd->o_con,
-			      CEPH_ENTITY_TYPE_OSD, o,
-			      &osdc->osdmap->osd_addr[o]);
+	if (ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD)) {
+		dout("%s PAUSERD\n", __func__);
+		return;
 	}
 
-	__enqueue_request(req);
-	err = 1;   /* osd or pg changed */
+	lreq->ping_sent = jiffies;
+	dout("%s lreq %p linger_id %llu ping_sent %lu register_gen %u\n",
+	     __func__, lreq, lreq->linger_id, lreq->ping_sent,
+	     lreq->register_gen);
 
-out:
-	return err;
+	if (req->r_osd)
+		cancel_linger_request(req);
+
+	request_reinit(req);
+	target_copy(&req->r_t, &lreq->t);
+
+	WARN_ON(op->op != CEPH_OSD_OP_WATCH ||
+		op->watch.cookie != lreq->linger_id ||
+		op->watch.op != CEPH_OSD_WATCH_OP_PING);
+	op->watch.gen = lreq->register_gen;
+	req->r_callback = linger_ping_cb;
+	req->r_priv = linger_get(lreq);
+	req->r_linger = true;
+
+	ceph_osdc_get_request(req);
+	account_request(req);
+	req->r_tid = atomic64_inc_return(&osdc->last_tid);
+	link_request(lreq->osd, req);
+	send_request(req);
 }
 
-/*
- * caller should hold map_sem (for read) and request_mutex
- */
-static void __send_request(struct ceph_osd_client *osdc,
-			   struct ceph_osd_request *req)
+static void linger_submit(struct ceph_osd_linger_request *lreq)
 {
-	void *p;
+	struct ceph_osd_client *osdc = lreq->osdc;
+	struct ceph_osd *osd;
 
-	dout("send_request %p tid %llu to osd%d flags %d pg %lld.%x\n",
-	     req, req->r_tid, req->r_osd->o_osd, req->r_flags,
-	     (unsigned long long)req->r_pgid.pool, req->r_pgid.seed);
+	calc_target(osdc, &lreq->t, &lreq->last_force_resend, false);
+	osd = lookup_create_osd(osdc, lreq->t.osd, true);
+	link_linger(osd, lreq);
 
-	/* fill in message content that changes each time we send it */
-	put_unaligned_le32(osdc->osdmap->epoch, req->r_request_osdmap_epoch);
-	put_unaligned_le32(req->r_flags, req->r_request_flags);
-	put_unaligned_le64(req->r_target_oloc.pool, req->r_request_pool);
-	p = req->r_request_pgid;
-	ceph_encode_64(&p, req->r_pgid.pool);
-	ceph_encode_32(&p, req->r_pgid.seed);
-	put_unaligned_le64(1, req->r_request_attempts);  /* FIXME */
-	memcpy(req->r_request_reassert_version, &req->r_reassert_version,
-	       sizeof(req->r_reassert_version));
+	send_linger(lreq);
+}
 
-	req->r_stamp = jiffies;
-	list_move_tail(&req->r_req_lru_item, &osdc->req_lru);
+static void cancel_linger_map_check(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
+	struct ceph_osd_linger_request *lookup_lreq;
 
-	ceph_msg_get(req->r_request); /* send consumes a ref */
+	verify_osdc_wrlocked(osdc);
 
-	req->r_sent = req->r_osd->o_incarnation;
+	lookup_lreq = lookup_linger_mc(&osdc->linger_map_checks,
+				       lreq->linger_id);
+	if (!lookup_lreq)
+		return;
 
-	ceph_con_send(&req->r_osd->o_con, req->r_request);
+	WARN_ON(lookup_lreq != lreq);
+	erase_linger_mc(&osdc->linger_map_checks, lreq);
+	linger_put(lreq);
 }
 
 /*
- * Send any requests in the queue (req_unsent).
+ * @lreq has to be both registered and linked.
  */
-static void __send_queued(struct ceph_osd_client *osdc)
+static void __linger_cancel(struct ceph_osd_linger_request *lreq)
 {
-	struct ceph_osd_request *req, *tmp;
+	if (lreq->is_watch && lreq->ping_req->r_osd)
+		cancel_linger_request(lreq->ping_req);
+	if (lreq->reg_req->r_osd)
+		cancel_linger_request(lreq->reg_req);
+	cancel_linger_map_check(lreq);
+	unlink_linger(lreq->osd, lreq);
+	linger_unregister(lreq);
+}
+
+static void linger_cancel(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
 
-	dout("__send_queued\n");
-	list_for_each_entry_safe(req, tmp, &osdc->req_unsent, r_req_lru_item)
-		__send_request(osdc, req);
+	down_write(&osdc->lock);
+	if (__linger_registered(lreq))
+		__linger_cancel(lreq);
+	up_write(&osdc->lock);
 }
 
-/*
- * Caller should hold map_sem for read and request_mutex.
- */
-static int __ceph_osdc_start_request(struct ceph_osd_client *osdc,
-				     struct ceph_osd_request *req,
-				     bool nofail)
-{
-	int rc;
-
-	__register_request(osdc, req);
-	req->r_sent = 0;
-	req->r_got_reply = 0;
-	rc = __map_request(osdc, req, 0);
-	if (rc < 0) {
-		if (nofail) {
-			dout("osdc_start_request failed map, "
-				" will retry %lld\n", req->r_tid);
-			rc = 0;
-		} else {
-			__unregister_request(osdc, req);
-		}
-		return rc;
+static void send_linger_map_check(struct ceph_osd_linger_request *lreq);
+
+static void check_linger_pool_dne(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
+	struct ceph_osdmap *map = osdc->osdmap;
+
+	verify_osdc_wrlocked(osdc);
+	WARN_ON(!map->epoch);
+
+	if (lreq->register_gen) {
+		lreq->map_dne_bound = map->epoch;
+		dout("%s lreq %p linger_id %llu pool disappeared\n", __func__,
+		     lreq, lreq->linger_id);
+	} else {
+		dout("%s lreq %p linger_id %llu map_dne_bound %u have %u\n",
+		     __func__, lreq, lreq->linger_id, lreq->map_dne_bound,
+		     map->epoch);
 	}
 
-	if (req->r_osd == NULL) {
-		dout("send_request %p no up osds in pg\n", req);
-		ceph_monc_request_next_osdmap(&osdc->client->monc);
+	if (lreq->map_dne_bound) {
+		if (map->epoch >= lreq->map_dne_bound) {
+			/* we had a new enough map */
+			pr_info("linger_id %llu pool does not exist\n",
+				lreq->linger_id);
+			linger_reg_commit_complete(lreq, -ENOENT);
+			__linger_cancel(lreq);
+		}
 	} else {
-		__send_queued(osdc);
+		send_linger_map_check(lreq);
 	}
+}
 
-	return 0;
+static void linger_map_check_cb(struct ceph_mon_generic_request *greq)
+{
+	struct ceph_osd_client *osdc = &greq->monc->client->osdc;
+	struct ceph_osd_linger_request *lreq;
+	u64 linger_id = greq->private_data;
+
+	WARN_ON(greq->result || !greq->u.newest);
+
+	down_write(&osdc->lock);
+	lreq = lookup_linger_mc(&osdc->linger_map_checks, linger_id);
+	if (!lreq) {
+		dout("%s linger_id %llu dne\n", __func__, linger_id);
+		goto out_unlock;
+	}
+
+	dout("%s lreq %p linger_id %llu map_dne_bound %u newest %llu\n",
+	     __func__, lreq, lreq->linger_id, lreq->map_dne_bound,
+	     greq->u.newest);
+	if (!lreq->map_dne_bound)
+		lreq->map_dne_bound = greq->u.newest;
+	erase_linger_mc(&osdc->linger_map_checks, lreq);
+	check_linger_pool_dne(lreq);
+
+	linger_put(lreq);
+out_unlock:
+	up_write(&osdc->lock);
+}
+
+static void send_linger_map_check(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_client *osdc = lreq->osdc;
+	struct ceph_osd_linger_request *lookup_lreq;
+	int ret;
+
+	verify_osdc_wrlocked(osdc);
+
+	lookup_lreq = lookup_linger_mc(&osdc->linger_map_checks,
+				       lreq->linger_id);
+	if (lookup_lreq) {
+		WARN_ON(lookup_lreq != lreq);
+		return;
+	}
+
+	linger_get(lreq);
+	insert_linger_mc(&osdc->linger_map_checks, lreq);
+	ret = ceph_monc_get_version_async(&osdc->client->monc, "osdmap",
+					  linger_map_check_cb, lreq->linger_id);
+	WARN_ON(ret);
+}
+
+static int linger_reg_commit_wait(struct ceph_osd_linger_request *lreq)
+{
+	int ret;
+
+	dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
+	ret = wait_for_completion_interruptible(&lreq->reg_commit_wait);
+	return ret ?: lreq->reg_commit_error;
+}
+
+static int linger_notify_finish_wait(struct ceph_osd_linger_request *lreq)
+{
+	int ret;
+
+	dout("%s lreq %p linger_id %llu\n", __func__, lreq, lreq->linger_id);
+	ret = wait_for_completion_interruptible(&lreq->notify_finish_wait);
+	return ret ?: lreq->notify_finish_error;
 }
 
 /*
- * Timeout callback, called every N seconds when 1 or more osd
- * requests has been active for more than N seconds.  When this
- * happens, we ping all OSDs with requests who have timed out to
- * ensure any communications channel reset is detected.  Reset the
- * request timeouts another N seconds in the future as we go.
- * Reschedule the timeout event another N seconds in future (unless
- * there are no open requests).
+ * Timeout callback, called every N seconds.  When 1 or more OSD
+ * requests has been active for more than N seconds, we send a keepalive
+ * (tag + timestamp) to its OSD to ensure any communications channel
+ * reset is detected.
  */
 static void handle_timeout(struct work_struct *work)
 {
 	struct ceph_osd_client *osdc =
 		container_of(work, struct ceph_osd_client, timeout_work.work);
 	struct ceph_options *opts = osdc->client->options;
-	struct ceph_osd_request *req;
-	struct ceph_osd *osd;
-	struct list_head slow_osds;
-	dout("timeout\n");
-	down_read(&osdc->map_sem);
-
-	ceph_monc_request_next_osdmap(&osdc->client->monc);
+	unsigned long cutoff = jiffies - opts->osd_keepalive_timeout;
+	LIST_HEAD(slow_osds);
+	struct rb_node *n, *p;
 
-	mutex_lock(&osdc->request_mutex);
+	dout("%s osdc %p\n", __func__, osdc);
+	down_write(&osdc->lock);
 
 	/*
 	 * ping osds that are a bit slow.  this ensures that if there
 	 * is a break in the TCP connection we will notice, and reopen
 	 * a connection with that osd (from the fault callback).
 	 */
-	INIT_LIST_HEAD(&slow_osds);
-	list_for_each_entry(req, &osdc->req_lru, r_req_lru_item) {
-		if (time_before(jiffies,
-				req->r_stamp + opts->osd_keepalive_timeout))
-			break;
+	for (n = rb_first(&osdc->osds); n; n = rb_next(n)) {
+		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
+		bool found = false;
+
+		for (p = rb_first(&osd->o_requests); p; p = rb_next(p)) {
+			struct ceph_osd_request *req =
+			    rb_entry(p, struct ceph_osd_request, r_node);
+
+			if (time_before(req->r_stamp, cutoff)) {
+				dout(" req %p tid %llu on osd%d is laggy\n",
+				     req, req->r_tid, osd->o_osd);
+				found = true;
+			}
+		}
+		for (p = rb_first(&osd->o_linger_requests); p; p = rb_next(p)) {
+			struct ceph_osd_linger_request *lreq =
+			    rb_entry(p, struct ceph_osd_linger_request, node);
+
+			dout(" lreq %p linger_id %llu is served by osd%d\n",
+			     lreq, lreq->linger_id, osd->o_osd);
+			found = true;
+
+			mutex_lock(&lreq->lock);
+			if (lreq->is_watch && lreq->committed && !lreq->last_error)
+				send_linger_ping(lreq);
+			mutex_unlock(&lreq->lock);
+		}
 
-		osd = req->r_osd;
-		BUG_ON(!osd);
-		dout(" tid %llu is slow, will send keepalive on osd%d\n",
-		     req->r_tid, osd->o_osd);
-		list_move_tail(&osd->o_keepalive_item, &slow_osds);
+		if (found)
+			list_move_tail(&osd->o_keepalive_item, &slow_osds);
 	}
+
+	if (atomic_read(&osdc->num_homeless) || !list_empty(&slow_osds))
+		maybe_request_map(osdc);
+
 	while (!list_empty(&slow_osds)) {
-		osd = list_entry(slow_osds.next, struct ceph_osd,
-				 o_keepalive_item);
+		struct ceph_osd *osd = list_first_entry(&slow_osds,
+							struct ceph_osd,
+							o_keepalive_item);
 		list_del_init(&osd->o_keepalive_item);
 		ceph_con_keepalive(&osd->o_con);
 	}
 
-	__schedule_osd_timeout(osdc);
-	__send_queued(osdc);
-	mutex_unlock(&osdc->request_mutex);
-	up_read(&osdc->map_sem);
+	up_write(&osdc->lock);
+	schedule_delayed_work(&osdc->timeout_work,
+			      osdc->client->options->osd_keepalive_timeout);
 }
 
 static void handle_osds_timeout(struct work_struct *work)
@@ -1663,12 +2541,20 @@ static void handle_osds_timeout(struct work_struct *work)
 		container_of(work, struct ceph_osd_client,
 			     osds_timeout_work.work);
 	unsigned long delay = osdc->client->options->osd_idle_ttl / 4;
+	struct ceph_osd *osd, *nosd;
 
-	dout("osds timeout\n");
-	down_read(&osdc->map_sem);
-	remove_old_osds(osdc);
-	up_read(&osdc->map_sem);
+	dout("%s osdc %p\n", __func__, osdc);
+	down_write(&osdc->lock);
+	list_for_each_entry_safe(osd, nosd, &osdc->osd_lru, o_osd_lru) {
+		if (time_before(jiffies, osd->lru_ttl))
+			break;
 
+		WARN_ON(!RB_EMPTY_ROOT(&osd->o_requests));
+		WARN_ON(!RB_EMPTY_ROOT(&osd->o_linger_requests));
+		close_osd(osd);
+	}
+
+	up_write(&osdc->lock);
 	schedule_delayed_work(&osdc->osds_timeout_work,
 			      round_jiffies_relative(delay));
 }
@@ -1776,107 +2662,76 @@ e_inval:
 	goto out;
 }
 
-static void complete_request(struct ceph_osd_request *req)
-{
-	complete_all(&req->r_safe_completion);  /* fsync waiter */
-}
+struct MOSDOpReply {
+	struct ceph_pg pgid;
+	u64 flags;
+	int result;
+	u32 epoch;
+	int num_ops;
+	u32 outdata_len[CEPH_OSD_MAX_OPS];
+	s32 rval[CEPH_OSD_MAX_OPS];
+	int retry_attempt;
+	struct ceph_eversion replay_version;
+	u64 user_version;
+	struct ceph_request_redirect redirect;
+};
 
-/*
- * handle osd op reply.  either call the callback if it is specified,
- * or do the completion to wake up the waiting thread.
- */
-static void handle_reply(struct ceph_osd_client *osdc, struct ceph_msg *msg)
+static int decode_MOSDOpReply(const struct ceph_msg *msg, struct MOSDOpReply *m)
 {
-	void *p, *end;
-	struct ceph_osd_request *req;
-	struct ceph_request_redirect redir;
-	u64 tid;
-	int object_len;
-	unsigned int numops;
-	int payload_len, flags;
-	s32 result;
-	s32 retry_attempt;
-	struct ceph_pg pg;
-	int err;
-	u32 reassert_epoch;
-	u64 reassert_version;
-	u32 osdmap_epoch;
-	int already_completed;
-	u32 bytes;
+	void *p = msg->front.iov_base;
+	void *const end = p + msg->front.iov_len;
+	u16 version = le16_to_cpu(msg->hdr.version);
+	struct ceph_eversion bad_replay_version;
 	u8 decode_redir;
-	unsigned int i;
-
-	tid = le64_to_cpu(msg->hdr.tid);
-	dout("handle_reply %p tid %llu\n", msg, tid);
+	u32 len;
+	int ret;
+	int i;
 
-	p = msg->front.iov_base;
-	end = p + msg->front.iov_len;
+	ceph_decode_32_safe(&p, end, len, e_inval);
+	ceph_decode_need(&p, end, len, e_inval);
+	p += len; /* skip oid */
 
-	ceph_decode_need(&p, end, 4, bad);
-	object_len = ceph_decode_32(&p);
-	ceph_decode_need(&p, end, object_len, bad);
-	p += object_len;
+	ret = ceph_decode_pgid(&p, end, &m->pgid);
+	if (ret)
+		return ret;
 
-	err = ceph_decode_pgid(&p, end, &pg);
-	if (err)
-		goto bad;
+	ceph_decode_64_safe(&p, end, m->flags, e_inval);
+	ceph_decode_32_safe(&p, end, m->result, e_inval);
+	ceph_decode_need(&p, end, sizeof(bad_replay_version), e_inval);
+	memcpy(&bad_replay_version, p, sizeof(bad_replay_version));
+	p += sizeof(bad_replay_version);
+	ceph_decode_32_safe(&p, end, m->epoch, e_inval);
 
-	ceph_decode_need(&p, end, 8 + 4 + 4 + 8 + 4, bad);
-	flags = ceph_decode_64(&p);
-	result = ceph_decode_32(&p);
-	reassert_epoch = ceph_decode_32(&p);
-	reassert_version = ceph_decode_64(&p);
-	osdmap_epoch = ceph_decode_32(&p);
-
-	/* lookup */
-	down_read(&osdc->map_sem);
-	mutex_lock(&osdc->request_mutex);
-	req = __lookup_request(osdc, tid);
-	if (req == NULL) {
-		dout("handle_reply tid %llu dne\n", tid);
-		goto bad_mutex;
-	}
-	ceph_osdc_get_request(req);
+	ceph_decode_32_safe(&p, end, m->num_ops, e_inval);
+	if (m->num_ops > ARRAY_SIZE(m->outdata_len))
+		goto e_inval;
 
-	dout("handle_reply %p tid %llu req %p result %d\n", msg, tid,
-	     req, result);
-
-	ceph_decode_need(&p, end, 4, bad_put);
-	numops = ceph_decode_32(&p);
-	if (numops > CEPH_OSD_MAX_OPS)
-		goto bad_put;
-	if (numops != req->r_num_ops)
-		goto bad_put;
-	payload_len = 0;
-	ceph_decode_need(&p, end, numops * sizeof(struct ceph_osd_op), bad_put);
-	for (i = 0; i < numops; i++) {
+	ceph_decode_need(&p, end, m->num_ops * sizeof(struct ceph_osd_op),
+			 e_inval);
+	for (i = 0; i < m->num_ops; i++) {
 		struct ceph_osd_op *op = p;
-		int len;
 
-		len = le32_to_cpu(op->payload_len);
-		req->r_ops[i].outdata_len = len;
-		dout(" op %d has %d bytes\n", i, len);
-		payload_len += len;
+		m->outdata_len[i] = le32_to_cpu(op->payload_len);
 		p += sizeof(*op);
 	}
-	bytes = le32_to_cpu(msg->hdr.data_len);
-	if (payload_len != bytes) {
-		pr_warn("sum of op payload lens %d != data_len %d\n",
-			payload_len, bytes);
-		goto bad_put;
-	}
 
-	ceph_decode_need(&p, end, 4 + numops * 4, bad_put);
-	retry_attempt = ceph_decode_32(&p);
-	for (i = 0; i < numops; i++)
-		req->r_ops[i].rval = ceph_decode_32(&p);
+	ceph_decode_32_safe(&p, end, m->retry_attempt, e_inval);
+	for (i = 0; i < m->num_ops; i++)
+		ceph_decode_32_safe(&p, end, m->rval[i], e_inval);
 
-	if (le16_to_cpu(msg->hdr.version) >= 6) {
-		p += 8 + 4; /* skip replay_version */
-		p += 8; /* skip user_version */
+	if (version >= 5) {
+		ceph_decode_need(&p, end, sizeof(m->replay_version), e_inval);
+		memcpy(&m->replay_version, p, sizeof(m->replay_version));
+		p += sizeof(m->replay_version);
+		ceph_decode_64_safe(&p, end, m->user_version, e_inval);
+	} else {
+		m->replay_version = bad_replay_version; /* struct */
+		m->user_version = le64_to_cpu(m->replay_version.version);
+	}
 
-		if (le16_to_cpu(msg->hdr.version) >= 7)
-			ceph_decode_8_safe(&p, end, decode_redir, bad_put);
+	if (version >= 6) {
+		if (version >= 7)
+			ceph_decode_8_safe(&p, end, decode_redir, e_inval);
 		else
 			decode_redir = 1;
 	} else {
@@ -1884,228 +2739,410 @@ static void handle_reply(struct ceph_osd_client *osdc, struct ceph_msg *msg)
 	}
 
 	if (decode_redir) {
-		err = ceph_redirect_decode(&p, end, &redir);
-		if (err)
-			goto bad_put;
+		ret = ceph_redirect_decode(&p, end, &m->redirect);
+		if (ret)
+			return ret;
 	} else {
-		redir.oloc.pool = -1;
+		ceph_oloc_init(&m->redirect.oloc);
 	}
 
-	if (redir.oloc.pool != -1) {
-		dout("redirect pool %lld\n", redir.oloc.pool);
+	return 0;
 
-		__unregister_request(osdc, req);
+e_inval:
+	return -EINVAL;
+}
 
-		req->r_target_oloc = redir.oloc; /* struct */
+/*
+ * We are done with @req if
+ *   - @m is a safe reply, or
+ *   - @m is an unsafe reply and we didn't want a safe one
+ */
+static bool done_request(const struct ceph_osd_request *req,
+			 const struct MOSDOpReply *m)
+{
+	return (m->result < 0 ||
+		(m->flags & CEPH_OSD_FLAG_ONDISK) ||
+		!(req->r_flags & CEPH_OSD_FLAG_ONDISK));
+}
 
-		/*
-		 * Start redirect requests with nofail=true.  If
-		 * mapping fails, request will end up on the notarget
-		 * list, waiting for the new osdmap (which can take
-		 * a while), even though the original request mapped
-		 * successfully.  In the future we might want to follow
-		 * original request's nofail setting here.
-		 */
-		err = __ceph_osdc_start_request(osdc, req, true);
-		BUG_ON(err);
+/*
+ * handle osd op reply.  either call the callback if it is specified,
+ * or do the completion to wake up the waiting thread.
+ *
+ * ->r_unsafe_callback is set?	yes			no
+ *
+ * first reply is OK (needed	r_cb/r_completion,	r_cb/r_completion,
+ * any or needed/got safe)	r_safe_completion	r_safe_completion
+ *
+ * first reply is unsafe	r_unsafe_cb(true)	(nothing)
+ *
+ * when we get the safe reply	r_unsafe_cb(false),	r_cb/r_completion,
+ *				r_safe_completion	r_safe_completion
+ */
+static void handle_reply(struct ceph_osd *osd, struct ceph_msg *msg)
+{
+	struct ceph_osd_client *osdc = osd->o_osdc;
+	struct ceph_osd_request *req;
+	struct MOSDOpReply m;
+	u64 tid = le64_to_cpu(msg->hdr.tid);
+	u32 data_len = 0;
+	bool already_acked;
+	int ret;
+	int i;
 
-		goto out_unlock;
-	}
+	dout("%s msg %p tid %llu\n", __func__, msg, tid);
 
-	already_completed = req->r_got_reply;
-	if (!req->r_got_reply) {
-		req->r_result = result;
-		dout("handle_reply result %d bytes %d\n", req->r_result,
-		     bytes);
-		if (req->r_result == 0)
-			req->r_result = bytes;
+	down_read(&osdc->lock);
+	if (!osd_registered(osd)) {
+		dout("%s osd%d unknown\n", __func__, osd->o_osd);
+		goto out_unlock_osdc;
+	}
+	WARN_ON(osd->o_osd != le64_to_cpu(msg->hdr.src.num));
 
-		/* in case this is a write and we need to replay, */
-		req->r_reassert_version.epoch = cpu_to_le32(reassert_epoch);
-		req->r_reassert_version.version = cpu_to_le64(reassert_version);
+	mutex_lock(&osd->lock);
+	req = lookup_request(&osd->o_requests, tid);
+	if (!req) {
+		dout("%s osd%d tid %llu unknown\n", __func__, osd->o_osd, tid);
+		goto out_unlock_session;
+	}
 
-		req->r_got_reply = 1;
-	} else if ((flags & CEPH_OSD_FLAG_ONDISK) == 0) {
-		dout("handle_reply tid %llu dup ack\n", tid);
-		goto out_unlock;
+	ret = decode_MOSDOpReply(msg, &m);
+	if (ret) {
+		pr_err("failed to decode MOSDOpReply for tid %llu: %d\n",
+		       req->r_tid, ret);
+		ceph_msg_dump(msg);
+		goto fail_request;
+	}
+	dout("%s req %p tid %llu flags 0x%llx pgid %llu.%x epoch %u attempt %d v %u'%llu uv %llu\n",
+	     __func__, req, req->r_tid, m.flags, m.pgid.pool, m.pgid.seed,
+	     m.epoch, m.retry_attempt, le32_to_cpu(m.replay_version.epoch),
+	     le64_to_cpu(m.replay_version.version), m.user_version);
+
+	if (m.retry_attempt >= 0) {
+		if (m.retry_attempt != req->r_attempts - 1) {
+			dout("req %p tid %llu retry_attempt %d != %d, ignoring\n",
+			     req, req->r_tid, m.retry_attempt,
+			     req->r_attempts - 1);
+			goto out_unlock_session;
+		}
+	} else {
+		WARN_ON(1); /* MOSDOpReply v4 is assumed */
 	}
 
-	dout("handle_reply tid %llu flags %d\n", tid, flags);
+	if (!ceph_oloc_empty(&m.redirect.oloc)) {
+		dout("req %p tid %llu redirect pool %lld\n", req, req->r_tid,
+		     m.redirect.oloc.pool);
+		unlink_request(osd, req);
+		mutex_unlock(&osd->lock);
+
+		ceph_oloc_copy(&req->r_t.target_oloc, &m.redirect.oloc);
+		req->r_flags |= CEPH_OSD_FLAG_REDIRECTED;
+		req->r_tid = 0;
+		__submit_request(req, false);
+		goto out_unlock_osdc;
+	}
 
-	if (req->r_linger && (flags & CEPH_OSD_FLAG_ONDISK))
-		__register_linger_request(osdc, req);
+	if (m.num_ops != req->r_num_ops) {
+		pr_err("num_ops %d != %d for tid %llu\n", m.num_ops,
+		       req->r_num_ops, req->r_tid);
+		goto fail_request;
+	}
+	for (i = 0; i < req->r_num_ops; i++) {
+		dout(" req %p tid %llu op %d rval %d len %u\n", req,
+		     req->r_tid, i, m.rval[i], m.outdata_len[i]);
+		req->r_ops[i].rval = m.rval[i];
+		req->r_ops[i].outdata_len = m.outdata_len[i];
+		data_len += m.outdata_len[i];
+	}
+	if (data_len != le32_to_cpu(msg->hdr.data_len)) {
+		pr_err("sum of lens %u != %u for tid %llu\n", data_len,
+		       le32_to_cpu(msg->hdr.data_len), req->r_tid);
+		goto fail_request;
+	}
+	dout("%s req %p tid %llu acked %d result %d data_len %u\n", __func__,
+	     req, req->r_tid, req->r_got_reply, m.result, data_len);
+
+	already_acked = req->r_got_reply;
+	if (!already_acked) {
+		req->r_result = m.result ?: data_len;
+		req->r_replay_version = m.replay_version; /* struct */
+		req->r_got_reply = true;
+	} else if (!(m.flags & CEPH_OSD_FLAG_ONDISK)) {
+		dout("req %p tid %llu dup ack\n", req, req->r_tid);
+		goto out_unlock_session;
+	}
 
-	/* either this is a read, or we got the safe response */
-	if (result < 0 ||
-	    (flags & CEPH_OSD_FLAG_ONDISK) ||
-	    ((flags & CEPH_OSD_FLAG_WRITE) == 0))
-		__unregister_request(osdc, req);
+	if (done_request(req, &m)) {
+		__finish_request(req);
+		if (req->r_linger) {
+			WARN_ON(req->r_unsafe_callback);
+			dout("req %p tid %llu cb (locked)\n", req, req->r_tid);
+			__complete_request(req);
+		}
+	}
 
-	mutex_unlock(&osdc->request_mutex);
-	up_read(&osdc->map_sem);
+	mutex_unlock(&osd->lock);
+	up_read(&osdc->lock);
 
-	if (!already_completed) {
-		if (req->r_unsafe_callback &&
-		    result >= 0 && !(flags & CEPH_OSD_FLAG_ONDISK))
+	if (done_request(req, &m)) {
+		if (already_acked && req->r_unsafe_callback) {
+			dout("req %p tid %llu safe-cb\n", req, req->r_tid);
+			req->r_unsafe_callback(req, false);
+		} else if (!req->r_linger) {
+			dout("req %p tid %llu cb\n", req, req->r_tid);
+			__complete_request(req);
+		}
+		if (m.flags & CEPH_OSD_FLAG_ONDISK)
+			complete_all(&req->r_safe_completion);
+		ceph_osdc_put_request(req);
+	} else {
+		if (req->r_unsafe_callback) {
+			dout("req %p tid %llu unsafe-cb\n", req, req->r_tid);
 			req->r_unsafe_callback(req, true);
-		if (req->r_callback)
-			req->r_callback(req, msg);
-		else
-			complete_all(&req->r_completion);
+		} else {
+			WARN_ON(1);
+		}
 	}
 
-	if (flags & CEPH_OSD_FLAG_ONDISK) {
-		if (req->r_unsafe_callback && already_completed)
-			req->r_unsafe_callback(req, false);
-		complete_request(req);
+	return;
+
+fail_request:
+	complete_request(req, -EIO);
+out_unlock_session:
+	mutex_unlock(&osd->lock);
+out_unlock_osdc:
+	up_read(&osdc->lock);
+}
+
+static void set_pool_was_full(struct ceph_osd_client *osdc)
+{
+	struct rb_node *n;
+
+	for (n = rb_first(&osdc->osdmap->pg_pools); n; n = rb_next(n)) {
+		struct ceph_pg_pool_info *pi =
+		    rb_entry(n, struct ceph_pg_pool_info, node);
+
+		pi->was_full = __pool_full(pi);
 	}
+}
 
-out:
-	dout("req=%p req->r_linger=%d\n", req, req->r_linger);
-	ceph_osdc_put_request(req);
-	return;
-out_unlock:
-	mutex_unlock(&osdc->request_mutex);
-	up_read(&osdc->map_sem);
-	goto out;
+static bool pool_cleared_full(struct ceph_osd_client *osdc, s64 pool_id)
+{
+	struct ceph_pg_pool_info *pi;
 
-bad_put:
-	req->r_result = -EIO;
-	__unregister_request(osdc, req);
-	if (req->r_callback)
-		req->r_callback(req, msg);
-	else
-		complete_all(&req->r_completion);
-	complete_request(req);
-	ceph_osdc_put_request(req);
-bad_mutex:
-	mutex_unlock(&osdc->request_mutex);
-	up_read(&osdc->map_sem);
-bad:
-	pr_err("corrupt osd_op_reply got %d %d\n",
-	       (int)msg->front.iov_len, le32_to_cpu(msg->hdr.front_len));
-	ceph_msg_dump(msg);
+	pi = ceph_pg_pool_by_id(osdc->osdmap, pool_id);
+	if (!pi)
+		return false;
+
+	return pi->was_full && !__pool_full(pi);
 }
 
-static void reset_changed_osds(struct ceph_osd_client *osdc)
+static enum calc_target_result
+recalc_linger_target(struct ceph_osd_linger_request *lreq)
 {
-	struct rb_node *p, *n;
+	struct ceph_osd_client *osdc = lreq->osdc;
+	enum calc_target_result ct_res;
 
-	dout("%s %p\n", __func__, osdc);
-	for (p = rb_first(&osdc->osds); p; p = n) {
-		struct ceph_osd *osd = rb_entry(p, struct ceph_osd, o_node);
+	ct_res = calc_target(osdc, &lreq->t, &lreq->last_force_resend, true);
+	if (ct_res == CALC_TARGET_NEED_RESEND) {
+		struct ceph_osd *osd;
 
-		n = rb_next(p);
-		if (!ceph_osd_is_up(osdc->osdmap, osd->o_osd) ||
-		    memcmp(&osd->o_con.peer_addr,
-			   ceph_osd_addr(osdc->osdmap,
-					 osd->o_osd),
-			   sizeof(struct ceph_entity_addr)) != 0)
-			__reset_osd(osdc, osd);
+		osd = lookup_create_osd(osdc, lreq->t.osd, true);
+		if (osd != lreq->osd) {
+			unlink_linger(lreq->osd, lreq);
+			link_linger(osd, lreq);
+		}
 	}
+
+	return ct_res;
 }
 
 /*
- * 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.
+ * Requeue requests whose mapping to an OSD has changed.
  */
-static void kick_requests(struct ceph_osd_client *osdc, bool force_resend,
-			  bool force_resend_writes)
+static void scan_requests(struct ceph_osd *osd,
+			  bool force_resend,
+			  bool cleared_full,
+			  bool check_pool_cleared_full,
+			  struct rb_root *need_resend,
+			  struct list_head *need_resend_linger)
 {
-	struct ceph_osd_request *req, *nreq;
-	struct rb_node *p;
-	int needmap = 0;
-	int err;
-	bool force_resend_req;
+	struct ceph_osd_client *osdc = osd->o_osdc;
+	struct rb_node *n;
+	bool force_resend_writes;
+
+	for (n = rb_first(&osd->o_linger_requests); n; ) {
+		struct ceph_osd_linger_request *lreq =
+		    rb_entry(n, struct ceph_osd_linger_request, node);
+		enum calc_target_result ct_res;
+
+		n = rb_next(n); /* recalc_linger_target() */
+
+		dout("%s lreq %p linger_id %llu\n", __func__, lreq,
+		     lreq->linger_id);
+		ct_res = recalc_linger_target(lreq);
+		switch (ct_res) {
+		case CALC_TARGET_NO_ACTION:
+			force_resend_writes = cleared_full ||
+			    (check_pool_cleared_full &&
+			     pool_cleared_full(osdc, lreq->t.base_oloc.pool));
+			if (!force_resend && !force_resend_writes)
+				break;
+
+			/* fall through */
+		case CALC_TARGET_NEED_RESEND:
+			cancel_linger_map_check(lreq);
+			/*
+			 * scan_requests() for the previous epoch(s)
+			 * may have already added it to the list, since
+			 * it's not unlinked here.
+			 */
+			if (list_empty(&lreq->scan_item))
+				list_add_tail(&lreq->scan_item, need_resend_linger);
+			break;
+		case CALC_TARGET_POOL_DNE:
+			check_linger_pool_dne(lreq);
+			break;
+		}
+	}
 
-	dout("kick_requests %s %s\n", force_resend ? " (force resend)" : "",
-		force_resend_writes ? " (force resend writes)" : "");
-	mutex_lock(&osdc->request_mutex);
-	for (p = rb_first(&osdc->requests); p; ) {
-		req = rb_entry(p, struct ceph_osd_request, r_node);
-		p = rb_next(p);
+	for (n = rb_first(&osd->o_requests); n; ) {
+		struct ceph_osd_request *req =
+		    rb_entry(n, struct ceph_osd_request, r_node);
+		enum calc_target_result ct_res;
+
+		n = rb_next(n); /* unlink_request(), check_pool_dne() */
+
+		dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
+		ct_res = calc_target(osdc, &req->r_t,
+				     &req->r_last_force_resend, false);
+		switch (ct_res) {
+		case CALC_TARGET_NO_ACTION:
+			force_resend_writes = cleared_full ||
+			    (check_pool_cleared_full &&
+			     pool_cleared_full(osdc, req->r_t.base_oloc.pool));
+			if (!force_resend &&
+			    (!(req->r_flags & CEPH_OSD_FLAG_WRITE) ||
+			     !force_resend_writes))
+				break;
+
+			/* fall through */
+		case CALC_TARGET_NEED_RESEND:
+			cancel_map_check(req);
+			unlink_request(osd, req);
+			insert_request(need_resend, req);
+			break;
+		case CALC_TARGET_POOL_DNE:
+			check_pool_dne(req);
+			break;
+		}
+	}
+}
 
+static int handle_one_map(struct ceph_osd_client *osdc,
+			  void *p, void *end, bool incremental,
+			  struct rb_root *need_resend,
+			  struct list_head *need_resend_linger)
+{
+	struct ceph_osdmap *newmap;
+	struct rb_node *n;
+	bool skipped_map = false;
+	bool was_full;
+
+	was_full = ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL);
+	set_pool_was_full(osdc);
+
+	if (incremental)
+		newmap = osdmap_apply_incremental(&p, end, osdc->osdmap);
+	else
+		newmap = ceph_osdmap_decode(&p, end);
+	if (IS_ERR(newmap))
+		return PTR_ERR(newmap);
+
+	if (newmap != osdc->osdmap) {
 		/*
-		 * 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.
+		 * Preserve ->was_full before destroying the old map.
+		 * For pools that weren't in the old map, ->was_full
+		 * should be false.
 		 */
-		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);
-			ceph_osdc_get_request(req);
-			__unregister_request(osdc, req);
-			__register_linger_request(osdc, req);
-			ceph_osdc_put_request(req);
-			continue;
+		for (n = rb_first(&newmap->pg_pools); n; n = rb_next(n)) {
+			struct ceph_pg_pool_info *pi =
+			    rb_entry(n, struct ceph_pg_pool_info, node);
+			struct ceph_pg_pool_info *old_pi;
+
+			old_pi = ceph_pg_pool_by_id(osdc->osdmap, pi->id);
+			if (old_pi)
+				pi->was_full = old_pi->was_full;
+			else
+				WARN_ON(pi->was_full);
 		}
 
-		force_resend_req = force_resend ||
-			(force_resend_writes &&
-				req->r_flags & CEPH_OSD_FLAG_WRITE);
-		err = __map_request(osdc, req, force_resend_req);
-		if (err < 0)
-			continue;  /* error */
-		if (req->r_osd == NULL) {
-			dout("%p tid %llu maps to no osd\n", req, req->r_tid);
-			needmap++;  /* request a newer map */
-		} else if (err > 0) {
-			if (!req->r_linger) {
-				dout("%p tid %llu requeued on osd%d\n", req,
-				     req->r_tid,
-				     req->r_osd ? req->r_osd->o_osd : -1);
-				req->r_flags |= CEPH_OSD_FLAG_RETRY;
-			}
+		if (osdc->osdmap->epoch &&
+		    osdc->osdmap->epoch + 1 < newmap->epoch) {
+			WARN_ON(incremental);
+			skipped_map = true;
 		}
+
+		ceph_osdmap_destroy(osdc->osdmap);
+		osdc->osdmap = newmap;
 	}
 
-	list_for_each_entry_safe(req, nreq, &osdc->req_linger,
-				 r_linger_item) {
-		dout("linger req=%p req->r_osd=%p\n", req, req->r_osd);
-
-		err = __map_request(osdc, req,
-				    force_resend || force_resend_writes);
-		dout("__map_request returned %d\n", err);
-		if (err < 0)
-			continue;  /* hrm! */
-		if (req->r_osd == NULL || err > 0) {
-			if (req->r_osd == NULL) {
-				dout("lingering %p tid %llu maps to no osd\n",
-				     req, req->r_tid);
-				/*
-				 * A homeless lingering request makes
-				 * no sense, as it's job is to keep
-				 * a particular OSD connection open.
-				 * Request a newer map and kick the
-				 * request, knowing that it won't be
-				 * resent until we actually get a map
-				 * that can tell us where to send it.
-				 */
-				needmap++;
-			}
+	was_full &= !ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL);
+	scan_requests(&osdc->homeless_osd, skipped_map, was_full, true,
+		      need_resend, need_resend_linger);
+
+	for (n = rb_first(&osdc->osds); n; ) {
+		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
+
+		n = rb_next(n); /* close_osd() */
+
+		scan_requests(osd, skipped_map, was_full, true, need_resend,
+			      need_resend_linger);
+		if (!ceph_osd_is_up(osdc->osdmap, osd->o_osd) ||
+		    memcmp(&osd->o_con.peer_addr,
+			   ceph_osd_addr(osdc->osdmap, osd->o_osd),
+			   sizeof(struct ceph_entity_addr)))
+			close_osd(osd);
+	}
 
-			dout("kicking lingering %p tid %llu osd%d\n", req,
-			     req->r_tid, req->r_osd ? req->r_osd->o_osd : -1);
-			__register_request(osdc, req);
-			__unregister_linger_request(osdc, req);
+	return 0;
+}
+
+static void kick_requests(struct ceph_osd_client *osdc,
+			  struct rb_root *need_resend,
+			  struct list_head *need_resend_linger)
+{
+	struct ceph_osd_linger_request *lreq, *nlreq;
+	struct rb_node *n;
+
+	for (n = rb_first(need_resend); n; ) {
+		struct ceph_osd_request *req =
+		    rb_entry(n, struct ceph_osd_request, r_node);
+		struct ceph_osd *osd;
+
+		n = rb_next(n);
+		erase_request(need_resend, req); /* before link_request() */
+
+		WARN_ON(req->r_osd);
+		calc_target(osdc, &req->r_t, NULL, false);
+		osd = lookup_create_osd(osdc, req->r_t.osd, true);
+		link_request(osd, req);
+		if (!req->r_linger) {
+			if (!osd_homeless(osd) && !req->r_t.paused)
+				send_request(req);
+		} else {
+			cancel_linger_request(req);
 		}
 	}
-	reset_changed_osds(osdc);
-	mutex_unlock(&osdc->request_mutex);
 
-	if (needmap) {
-		dout("%d requests for down osds, need new map\n", needmap);
-		ceph_monc_request_next_osdmap(&osdc->client->monc);
+	list_for_each_entry_safe(lreq, nlreq, need_resend_linger, scan_item) {
+		if (!osd_homeless(lreq->osd))
+			send_linger(lreq);
+
+		list_del_init(&lreq->scan_item);
 	}
 }
 
-
 /*
  * Process updated osd map.
  *
@@ -2115,27 +3152,31 @@ static void kick_requests(struct ceph_osd_client *osdc, bool force_resend,
  */
 void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
 {
-	void *p, *end, *next;
+	void *p = msg->front.iov_base;
+	void *const end = p + msg->front.iov_len;
 	u32 nr_maps, maplen;
 	u32 epoch;
-	struct ceph_osdmap *newmap = NULL, *oldmap;
-	int err;
 	struct ceph_fsid fsid;
-	bool was_full;
+	struct rb_root need_resend = RB_ROOT;
+	LIST_HEAD(need_resend_linger);
+	bool handled_incremental = false;
+	bool was_pauserd, was_pausewr;
+	bool pauserd, pausewr;
+	int err;
 
-	dout("handle_map have %u\n", osdc->osdmap ? osdc->osdmap->epoch : 0);
-	p = msg->front.iov_base;
-	end = p + msg->front.iov_len;
+	dout("%s have %u\n", __func__, osdc->osdmap->epoch);
+	down_write(&osdc->lock);
 
 	/* verify fsid */
 	ceph_decode_need(&p, end, sizeof(fsid), bad);
 	ceph_decode_copy(&p, &fsid, sizeof(fsid));
 	if (ceph_check_fsid(osdc->client, &fsid) < 0)
-		return;
-
-	down_write(&osdc->map_sem);
+		goto bad;
 
-	was_full = ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL);
+	was_pauserd = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD);
+	was_pausewr = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR) ||
+		      ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
+		      have_pool_full(osdc);
 
 	/* incremental maps */
 	ceph_decode_32_safe(&p, end, nr_maps, bad);
@@ -2145,34 +3186,23 @@ void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
 		epoch = ceph_decode_32(&p);
 		maplen = ceph_decode_32(&p);
 		ceph_decode_need(&p, end, maplen, bad);
-		next = p + maplen;
-		if (osdc->osdmap && osdc->osdmap->epoch+1 == epoch) {
+		if (osdc->osdmap->epoch &&
+		    osdc->osdmap->epoch + 1 == epoch) {
 			dout("applying incremental map %u len %d\n",
 			     epoch, maplen);
-			newmap = osdmap_apply_incremental(&p, next,
-							  osdc->osdmap,
-							  &osdc->client->msgr);
-			if (IS_ERR(newmap)) {
-				err = PTR_ERR(newmap);
+			err = handle_one_map(osdc, p, p + maplen, true,
+					     &need_resend, &need_resend_linger);
+			if (err)
 				goto bad;
-			}
-			BUG_ON(!newmap);
-			if (newmap != osdc->osdmap) {
-				ceph_osdmap_destroy(osdc->osdmap);
-				osdc->osdmap = newmap;
-			}
-			was_full = was_full ||
-				ceph_osdmap_flag(osdc->osdmap,
-						 CEPH_OSDMAP_FULL);
-			kick_requests(osdc, 0, was_full);
+			handled_incremental = true;
 		} else {
 			dout("ignoring incremental map %u len %d\n",
 			     epoch, maplen);
 		}
-		p = next;
+		p += maplen;
 		nr_maps--;
 	}
-	if (newmap)
+	if (handled_incremental)
 		goto done;
 
 	/* full maps */
@@ -2186,455 +3216,647 @@ void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
 		if (nr_maps > 1) {
 			dout("skipping non-latest full map %u len %d\n",
 			     epoch, maplen);
-		} else if (osdc->osdmap && osdc->osdmap->epoch >= epoch) {
+		} else if (osdc->osdmap->epoch >= epoch) {
 			dout("skipping full map %u len %d, "
 			     "older than our %u\n", epoch, maplen,
 			     osdc->osdmap->epoch);
 		} else {
-			int skipped_map = 0;
-
 			dout("taking full map %u len %d\n", epoch, maplen);
-			newmap = ceph_osdmap_decode(&p, p+maplen);
-			if (IS_ERR(newmap)) {
-				err = PTR_ERR(newmap);
+			err = handle_one_map(osdc, p, p + maplen, false,
+					     &need_resend, &need_resend_linger);
+			if (err)
 				goto bad;
-			}
-			BUG_ON(!newmap);
-			oldmap = osdc->osdmap;
-			osdc->osdmap = newmap;
-			if (oldmap) {
-				if (oldmap->epoch + 1 < newmap->epoch)
-					skipped_map = 1;
-				ceph_osdmap_destroy(oldmap);
-			}
-			was_full = was_full ||
-				ceph_osdmap_flag(osdc->osdmap,
-						 CEPH_OSDMAP_FULL);
-			kick_requests(osdc, skipped_map, was_full);
 		}
 		p += maplen;
 		nr_maps--;
 	}
 
-	if (!osdc->osdmap)
-		goto bad;
 done:
-	downgrade_write(&osdc->map_sem);
-	ceph_monc_got_map(&osdc->client->monc, CEPH_SUB_OSDMAP,
-			  osdc->osdmap->epoch);
-
 	/*
 	 * subscribe to subsequent osdmap updates if full to ensure
 	 * we find out when we are no longer full and stop returning
 	 * ENOSPC.
 	 */
-	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL) ||
-		ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_PAUSERD) ||
-		ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_PAUSEWR))
-		ceph_monc_request_next_osdmap(&osdc->client->monc);
-
-	mutex_lock(&osdc->request_mutex);
-	__send_queued(osdc);
-	mutex_unlock(&osdc->request_mutex);
-	up_read(&osdc->map_sem);
+	pauserd = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSERD);
+	pausewr = ceph_osdmap_flag(osdc, CEPH_OSDMAP_PAUSEWR) ||
+		  ceph_osdmap_flag(osdc, CEPH_OSDMAP_FULL) ||
+		  have_pool_full(osdc);
+	if (was_pauserd || was_pausewr || pauserd || pausewr)
+		maybe_request_map(osdc);
+
+	kick_requests(osdc, &need_resend, &need_resend_linger);
+
+	ceph_monc_got_map(&osdc->client->monc, CEPH_SUB_OSDMAP,
+			  osdc->osdmap->epoch);
+	up_write(&osdc->lock);
 	wake_up_all(&osdc->client->auth_wq);
 	return;
 
 bad:
 	pr_err("osdc handle_map corrupt msg\n");
 	ceph_msg_dump(msg);
-	up_write(&osdc->map_sem);
+	up_write(&osdc->lock);
 }
 
 /*
- * watch/notify callback event infrastructure
- *
- * These callbacks are used both for watch and notify operations.
+ * Resubmit requests pending on the given osd.
  */
-static void __release_event(struct kref *kref)
+static void kick_osd_requests(struct ceph_osd *osd)
 {
-	struct ceph_osd_event *event =
-		container_of(kref, struct ceph_osd_event, kref);
+	struct rb_node *n;
 
-	dout("__release_event %p\n", event);
-	kfree(event);
-}
+	for (n = rb_first(&osd->o_requests); n; ) {
+		struct ceph_osd_request *req =
+		    rb_entry(n, struct ceph_osd_request, r_node);
 
-static void get_event(struct ceph_osd_event *event)
-{
-	kref_get(&event->kref);
-}
+		n = rb_next(n); /* cancel_linger_request() */
 
-void ceph_osdc_put_event(struct ceph_osd_event *event)
-{
-	kref_put(&event->kref, __release_event);
+		if (!req->r_linger) {
+			if (!req->r_t.paused)
+				send_request(req);
+		} else {
+			cancel_linger_request(req);
+		}
+	}
+	for (n = rb_first(&osd->o_linger_requests); n; n = rb_next(n)) {
+		struct ceph_osd_linger_request *lreq =
+		    rb_entry(n, struct ceph_osd_linger_request, node);
+
+		send_linger(lreq);
+	}
 }
-EXPORT_SYMBOL(ceph_osdc_put_event);
 
-static void __insert_event(struct ceph_osd_client *osdc,
-			     struct ceph_osd_event *new)
+/*
+ * If the osd connection drops, we need to resubmit all requests.
+ */
+static void osd_fault(struct ceph_connection *con)
 {
-	struct rb_node **p = &osdc->event_tree.rb_node;
-	struct rb_node *parent = NULL;
-	struct ceph_osd_event *event = NULL;
+	struct ceph_osd *osd = con->private;
+	struct ceph_osd_client *osdc = osd->o_osdc;
 
-	while (*p) {
-		parent = *p;
-		event = rb_entry(parent, struct ceph_osd_event, node);
-		if (new->cookie < event->cookie)
-			p = &(*p)->rb_left;
-		else if (new->cookie > event->cookie)
-			p = &(*p)->rb_right;
-		else
-			BUG();
+	dout("%s osd %p osd%d\n", __func__, osd, osd->o_osd);
+
+	down_write(&osdc->lock);
+	if (!osd_registered(osd)) {
+		dout("%s osd%d unknown\n", __func__, osd->o_osd);
+		goto out_unlock;
 	}
 
-	rb_link_node(&new->node, parent, p);
-	rb_insert_color(&new->node, &osdc->event_tree);
+	if (!reopen_osd(osd))
+		kick_osd_requests(osd);
+	maybe_request_map(osdc);
+
+out_unlock:
+	up_write(&osdc->lock);
 }
 
-static struct ceph_osd_event *__find_event(struct ceph_osd_client *osdc,
-					        u64 cookie)
+/*
+ * Process osd watch notifications
+ */
+static void handle_watch_notify(struct ceph_osd_client *osdc,
+				struct ceph_msg *msg)
 {
-	struct rb_node **p = &osdc->event_tree.rb_node;
-	struct rb_node *parent = NULL;
-	struct ceph_osd_event *event = NULL;
+	void *p = msg->front.iov_base;
+	void *const end = p + msg->front.iov_len;
+	struct ceph_osd_linger_request *lreq;
+	struct linger_work *lwork;
+	u8 proto_ver, opcode;
+	u64 cookie, notify_id;
+	u64 notifier_id = 0;
+	s32 return_code = 0;
+	void *payload = NULL;
+	u32 payload_len = 0;
 
-	while (*p) {
-		parent = *p;
-		event = rb_entry(parent, struct ceph_osd_event, node);
-		if (cookie < event->cookie)
-			p = &(*p)->rb_left;
-		else if (cookie > event->cookie)
-			p = &(*p)->rb_right;
-		else
-			return event;
+	ceph_decode_8_safe(&p, end, proto_ver, bad);
+	ceph_decode_8_safe(&p, end, opcode, bad);
+	ceph_decode_64_safe(&p, end, cookie, bad);
+	p += 8; /* skip ver */
+	ceph_decode_64_safe(&p, end, notify_id, bad);
+
+	if (proto_ver >= 1) {
+		ceph_decode_32_safe(&p, end, payload_len, bad);
+		ceph_decode_need(&p, end, payload_len, bad);
+		payload = p;
+		p += payload_len;
 	}
-	return NULL;
-}
 
-static void __remove_event(struct ceph_osd_event *event)
-{
-	struct ceph_osd_client *osdc = event->osdc;
+	if (le16_to_cpu(msg->hdr.version) >= 2)
+		ceph_decode_32_safe(&p, end, return_code, bad);
+
+	if (le16_to_cpu(msg->hdr.version) >= 3)
+		ceph_decode_64_safe(&p, end, notifier_id, bad);
 
-	if (!RB_EMPTY_NODE(&event->node)) {
-		dout("__remove_event removed %p\n", event);
-		rb_erase(&event->node, &osdc->event_tree);
-		ceph_osdc_put_event(event);
+	down_read(&osdc->lock);
+	lreq = lookup_linger_osdc(&osdc->linger_requests, cookie);
+	if (!lreq) {
+		dout("%s opcode %d cookie %llu dne\n", __func__, opcode,
+		     cookie);
+		goto out_unlock_osdc;
+	}
+
+	mutex_lock(&lreq->lock);
+	dout("%s opcode %d cookie %llu lreq %p is_watch %d\n", __func__,
+	     opcode, cookie, lreq, lreq->is_watch);
+	if (opcode == CEPH_WATCH_EVENT_DISCONNECT) {
+		if (!lreq->last_error) {
+			lreq->last_error = -ENOTCONN;
+			queue_watch_error(lreq);
+		}
+	} else if (!lreq->is_watch) {
+		/* CEPH_WATCH_EVENT_NOTIFY_COMPLETE */
+		if (lreq->notify_id && lreq->notify_id != notify_id) {
+			dout("lreq %p notify_id %llu != %llu, ignoring\n", lreq,
+			     lreq->notify_id, notify_id);
+		} else if (!completion_done(&lreq->notify_finish_wait)) {
+			struct ceph_msg_data *data =
+			    list_first_entry_or_null(&msg->data,
+						     struct ceph_msg_data,
+						     links);
+
+			if (data) {
+				if (lreq->preply_pages) {
+					WARN_ON(data->type !=
+							CEPH_MSG_DATA_PAGES);
+					*lreq->preply_pages = data->pages;
+					*lreq->preply_len = data->length;
+				} else {
+					ceph_release_page_vector(data->pages,
+					       calc_pages_for(0, data->length));
+				}
+			}
+			lreq->notify_finish_error = return_code;
+			complete_all(&lreq->notify_finish_wait);
+		}
 	} else {
-		dout("__remove_event didn't remove %p\n", event);
+		/* CEPH_WATCH_EVENT_NOTIFY */
+		lwork = lwork_alloc(lreq, do_watch_notify);
+		if (!lwork) {
+			pr_err("failed to allocate notify-lwork\n");
+			goto out_unlock_lreq;
+		}
+
+		lwork->notify.notify_id = notify_id;
+		lwork->notify.notifier_id = notifier_id;
+		lwork->notify.payload = payload;
+		lwork->notify.payload_len = payload_len;
+		lwork->notify.msg = ceph_msg_get(msg);
+		lwork_queue(lwork);
 	}
+
+out_unlock_lreq:
+	mutex_unlock(&lreq->lock);
+out_unlock_osdc:
+	up_read(&osdc->lock);
+	return;
+
+bad:
+	pr_err("osdc handle_watch_notify corrupt msg\n");
 }
 
-int ceph_osdc_create_event(struct ceph_osd_client *osdc,
-			   void (*event_cb)(u64, u64, u8, void *),
-			   void *data, struct ceph_osd_event **pevent)
+/*
+ * Register request, send initial attempt.
+ */
+int ceph_osdc_start_request(struct ceph_osd_client *osdc,
+			    struct ceph_osd_request *req,
+			    bool nofail)
 {
-	struct ceph_osd_event *event;
+	down_read(&osdc->lock);
+	submit_request(req, false);
+	up_read(&osdc->lock);
 
-	event = kmalloc(sizeof(*event), GFP_NOIO);
-	if (!event)
-		return -ENOMEM;
-
-	dout("create_event %p\n", event);
-	event->cb = event_cb;
-	event->one_shot = 0;
-	event->data = data;
-	event->osdc = osdc;
-	INIT_LIST_HEAD(&event->osd_node);
-	RB_CLEAR_NODE(&event->node);
-	kref_init(&event->kref);   /* one ref for us */
-	kref_get(&event->kref);    /* one ref for the caller */
-
-	spin_lock(&osdc->event_lock);
-	event->cookie = ++osdc->event_count;
-	__insert_event(osdc, event);
-	spin_unlock(&osdc->event_lock);
-
-	*pevent = event;
 	return 0;
 }
-EXPORT_SYMBOL(ceph_osdc_create_event);
+EXPORT_SYMBOL(ceph_osdc_start_request);
 
-void ceph_osdc_cancel_event(struct ceph_osd_event *event)
+/*
+ * Unregister a registered request.  The request is not completed (i.e.
+ * no callbacks or wakeups) - higher layers are supposed to know what
+ * they are canceling.
+ */
+void ceph_osdc_cancel_request(struct ceph_osd_request *req)
 {
-	struct ceph_osd_client *osdc = event->osdc;
+	struct ceph_osd_client *osdc = req->r_osdc;
 
-	dout("cancel_event %p\n", event);
-	spin_lock(&osdc->event_lock);
-	__remove_event(event);
-	spin_unlock(&osdc->event_lock);
-	ceph_osdc_put_event(event); /* caller's */
+	down_write(&osdc->lock);
+	if (req->r_osd)
+		cancel_request(req);
+	up_write(&osdc->lock);
 }
-EXPORT_SYMBOL(ceph_osdc_cancel_event);
-
+EXPORT_SYMBOL(ceph_osdc_cancel_request);
 
-static void do_event_work(struct work_struct *work)
+/*
+ * @timeout: in jiffies, 0 means "wait forever"
+ */
+static int wait_request_timeout(struct ceph_osd_request *req,
+				unsigned long timeout)
 {
-	struct ceph_osd_event_work *event_work =
-		container_of(work, struct ceph_osd_event_work, work);
-	struct ceph_osd_event *event = event_work->event;
-	u64 ver = event_work->ver;
-	u64 notify_id = event_work->notify_id;
-	u8 opcode = event_work->opcode;
+	long left;
+
+	dout("%s req %p tid %llu\n", __func__, req, req->r_tid);
+	left = wait_for_completion_killable_timeout(&req->r_completion,
+						ceph_timeout_jiffies(timeout));
+	if (left <= 0) {
+		left = left ?: -ETIMEDOUT;
+		ceph_osdc_cancel_request(req);
 
-	dout("do_event_work completing %p\n", event);
-	event->cb(ver, notify_id, opcode, event->data);
-	dout("do_event_work completed %p\n", event);
-	ceph_osdc_put_event(event);
-	kfree(event_work);
+		/* kludge - need to to wake ceph_osdc_sync() */
+		complete_all(&req->r_safe_completion);
+	} else {
+		left = req->r_result; /* completed */
+	}
+
+	return left;
 }
 
+/*
+ * wait for a request to complete
+ */
+int ceph_osdc_wait_request(struct ceph_osd_client *osdc,
+			   struct ceph_osd_request *req)
+{
+	return wait_request_timeout(req, 0);
+}
+EXPORT_SYMBOL(ceph_osdc_wait_request);
 
 /*
- * Process osd watch notifications
+ * sync - wait for all in-flight requests to flush.  avoid starvation.
  */
-static void handle_watch_notify(struct ceph_osd_client *osdc,
-				struct ceph_msg *msg)
+void ceph_osdc_sync(struct ceph_osd_client *osdc)
 {
-	void *p, *end;
-	u8 proto_ver;
-	u64 cookie, ver, notify_id;
-	u8 opcode;
-	struct ceph_osd_event *event;
-	struct ceph_osd_event_work *event_work;
+	struct rb_node *n, *p;
+	u64 last_tid = atomic64_read(&osdc->last_tid);
 
-	p = msg->front.iov_base;
-	end = p + msg->front.iov_len;
+again:
+	down_read(&osdc->lock);
+	for (n = rb_first(&osdc->osds); n; n = rb_next(n)) {
+		struct ceph_osd *osd = rb_entry(n, struct ceph_osd, o_node);
 
-	ceph_decode_8_safe(&p, end, proto_ver, bad);
-	ceph_decode_8_safe(&p, end, opcode, bad);
-	ceph_decode_64_safe(&p, end, cookie, bad);
-	ceph_decode_64_safe(&p, end, ver, bad);
-	ceph_decode_64_safe(&p, end, notify_id, bad);
+		mutex_lock(&osd->lock);
+		for (p = rb_first(&osd->o_requests); p; p = rb_next(p)) {
+			struct ceph_osd_request *req =
+			    rb_entry(p, struct ceph_osd_request, r_node);
+
+			if (req->r_tid > last_tid)
+				break;
 
-	spin_lock(&osdc->event_lock);
-	event = __find_event(osdc, cookie);
-	if (event) {
-		BUG_ON(event->one_shot);
-		get_event(event);
-	}
-	spin_unlock(&osdc->event_lock);
-	dout("handle_watch_notify cookie %lld ver %lld event %p\n",
-	     cookie, ver, event);
-	if (event) {
-		event_work = kmalloc(sizeof(*event_work), GFP_NOIO);
-		if (!event_work) {
-			pr_err("couldn't allocate event_work\n");
-			ceph_osdc_put_event(event);
-			return;
+			if (!(req->r_flags & CEPH_OSD_FLAG_WRITE))
+				continue;
+
+			ceph_osdc_get_request(req);
+			mutex_unlock(&osd->lock);
+			up_read(&osdc->lock);
+			dout("%s waiting on req %p tid %llu last_tid %llu\n",
+			     __func__, req, req->r_tid, last_tid);
+			wait_for_completion(&req->r_safe_completion);
+			ceph_osdc_put_request(req);
+			goto again;
 		}
-		INIT_WORK(&event_work->work, do_event_work);
-		event_work->event = event;
-		event_work->ver = ver;
-		event_work->notify_id = notify_id;
-		event_work->opcode = opcode;
 
-		queue_work(osdc->notify_wq, &event_work->work);
+		mutex_unlock(&osd->lock);
 	}
 
-	return;
+	up_read(&osdc->lock);
+	dout("%s done last_tid %llu\n", __func__, last_tid);
+}
+EXPORT_SYMBOL(ceph_osdc_sync);
 
-bad:
-	pr_err("osdc handle_watch_notify corrupt msg\n");
+static struct ceph_osd_request *
+alloc_linger_request(struct ceph_osd_linger_request *lreq)
+{
+	struct ceph_osd_request *req;
+
+	req = ceph_osdc_alloc_request(lreq->osdc, NULL, 1, false, GFP_NOIO);
+	if (!req)
+		return NULL;
+
+	ceph_oid_copy(&req->r_base_oid, &lreq->t.base_oid);
+	ceph_oloc_copy(&req->r_base_oloc, &lreq->t.base_oloc);
+
+	if (ceph_osdc_alloc_messages(req, GFP_NOIO)) {
+		ceph_osdc_put_request(req);
+		return NULL;
+	}
+
+	return req;
 }
 
 /*
- * build new request AND message
- *
+ * Returns a handle, caller owns a ref.
  */
-void ceph_osdc_build_request(struct ceph_osd_request *req, u64 off,
-				struct ceph_snap_context *snapc, u64 snap_id,
-				struct timespec *mtime)
-{
-	struct ceph_msg *msg = req->r_request;
-	void *p;
-	size_t msg_size;
-	int flags = req->r_flags;
-	u64 data_len;
-	unsigned int i;
-
-	req->r_snapid = snap_id;
-	req->r_snapc = ceph_get_snap_context(snapc);
-
-	/* encode request */
-	msg->hdr.version = cpu_to_le16(4);
-
-	p = msg->front.iov_base;
-	ceph_encode_32(&p, 1);   /* client_inc  is always 1 */
-	req->r_request_osdmap_epoch = p;
-	p += 4;
-	req->r_request_flags = p;
-	p += 4;
-	if (req->r_flags & CEPH_OSD_FLAG_WRITE)
-		ceph_encode_timespec(p, mtime);
-	p += sizeof(struct ceph_timespec);
-	req->r_request_reassert_version = p;
-	p += sizeof(struct ceph_eversion); /* will get filled in */
-
-	/* oloc */
-	ceph_encode_8(&p, 4);
-	ceph_encode_8(&p, 4);
-	ceph_encode_32(&p, 8 + 4 + 4);
-	req->r_request_pool = p;
-	p += 8;
-	ceph_encode_32(&p, -1);  /* preferred */
-	ceph_encode_32(&p, 0);   /* key len */
+struct ceph_osd_linger_request *
+ceph_osdc_watch(struct ceph_osd_client *osdc,
+		struct ceph_object_id *oid,
+		struct ceph_object_locator *oloc,
+		rados_watchcb2_t wcb,
+		rados_watcherrcb_t errcb,
+		void *data)
+{
+	struct ceph_osd_linger_request *lreq;
+	int ret;
 
-	ceph_encode_8(&p, 1);
-	req->r_request_pgid = p;
-	p += 8 + 4;
-	ceph_encode_32(&p, -1);  /* preferred */
+	lreq = linger_alloc(osdc);
+	if (!lreq)
+		return ERR_PTR(-ENOMEM);
 
-	/* oid */
-	ceph_encode_32(&p, req->r_base_oid.name_len);
-	memcpy(p, req->r_base_oid.name, req->r_base_oid.name_len);
-	dout("oid '%.*s' len %d\n", req->r_base_oid.name_len,
-	     req->r_base_oid.name, req->r_base_oid.name_len);
-	p += req->r_base_oid.name_len;
-
-	/* ops--can imply data */
-	ceph_encode_16(&p, (u16)req->r_num_ops);
-	data_len = 0;
-	for (i = 0; i < req->r_num_ops; i++) {
-		data_len += osd_req_encode_op(req, p, i);
-		p += sizeof(struct ceph_osd_op);
+	lreq->is_watch = true;
+	lreq->wcb = wcb;
+	lreq->errcb = errcb;
+	lreq->data = data;
+	lreq->watch_valid_thru = jiffies;
+
+	ceph_oid_copy(&lreq->t.base_oid, oid);
+	ceph_oloc_copy(&lreq->t.base_oloc, oloc);
+	lreq->t.flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
+	lreq->mtime = CURRENT_TIME;
+
+	lreq->reg_req = alloc_linger_request(lreq);
+	if (!lreq->reg_req) {
+		ret = -ENOMEM;
+		goto err_put_lreq;
 	}
 
-	/* snaps */
-	ceph_encode_64(&p, req->r_snapid);
-	ceph_encode_64(&p, req->r_snapc ? req->r_snapc->seq : 0);
-	ceph_encode_32(&p, req->r_snapc ? req->r_snapc->num_snaps : 0);
-	if (req->r_snapc) {
-		for (i = 0; i < snapc->num_snaps; i++) {
-			ceph_encode_64(&p, req->r_snapc->snaps[i]);
-		}
+	lreq->ping_req = alloc_linger_request(lreq);
+	if (!lreq->ping_req) {
+		ret = -ENOMEM;
+		goto err_put_lreq;
 	}
 
-	req->r_request_attempts = p;
-	p += 4;
-
-	/* data */
-	if (flags & CEPH_OSD_FLAG_WRITE) {
-		u16 data_off;
-
-		/*
-		 * The header "data_off" is a hint to the receiver
-		 * allowing it to align received data into its
-		 * buffers such that there's no need to re-copy
-		 * it before writing it to disk (direct I/O).
-		 */
-		data_off = (u16) (off & 0xffff);
-		req->r_request->hdr.data_off = cpu_to_le16(data_off);
+	down_write(&osdc->lock);
+	linger_register(lreq); /* before osd_req_op_* */
+	osd_req_op_watch_init(lreq->reg_req, 0, lreq->linger_id,
+			      CEPH_OSD_WATCH_OP_WATCH);
+	osd_req_op_watch_init(lreq->ping_req, 0, lreq->linger_id,
+			      CEPH_OSD_WATCH_OP_PING);
+	linger_submit(lreq);
+	up_write(&osdc->lock);
+
+	ret = linger_reg_commit_wait(lreq);
+	if (ret) {
+		linger_cancel(lreq);
+		goto err_put_lreq;
 	}
-	req->r_request->hdr.data_len = cpu_to_le32(data_len);
 
-	BUG_ON(p > msg->front.iov_base + msg->front.iov_len);
-	msg_size = p - msg->front.iov_base;
-	msg->front.iov_len = msg_size;
-	msg->hdr.front_len = cpu_to_le32(msg_size);
+	return lreq;
 
-	dout("build_request msg_size was %d\n", (int)msg_size);
+err_put_lreq:
+	linger_put(lreq);
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL(ceph_osdc_build_request);
+EXPORT_SYMBOL(ceph_osdc_watch);
 
 /*
- * Register request, send initial attempt.
+ * Releases a ref.
+ *
+ * Times out after mount_timeout to preserve rbd unmap behaviour
+ * introduced in 2894e1d76974 ("rbd: timeout watch teardown on unmap
+ * with mount_timeout").
  */
-int ceph_osdc_start_request(struct ceph_osd_client *osdc,
-			    struct ceph_osd_request *req,
-			    bool nofail)
+int ceph_osdc_unwatch(struct ceph_osd_client *osdc,
+		      struct ceph_osd_linger_request *lreq)
 {
-	int rc;
+	struct ceph_options *opts = osdc->client->options;
+	struct ceph_osd_request *req;
+	int ret;
 
-	down_read(&osdc->map_sem);
-	mutex_lock(&osdc->request_mutex);
+	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_NOIO);
+	if (!req)
+		return -ENOMEM;
 
-	rc = __ceph_osdc_start_request(osdc, req, nofail);
+	ceph_oid_copy(&req->r_base_oid, &lreq->t.base_oid);
+	ceph_oloc_copy(&req->r_base_oloc, &lreq->t.base_oloc);
+	req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
+	req->r_mtime = CURRENT_TIME;
+	osd_req_op_watch_init(req, 0, lreq->linger_id,
+			      CEPH_OSD_WATCH_OP_UNWATCH);
 
-	mutex_unlock(&osdc->request_mutex);
-	up_read(&osdc->map_sem);
+	ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
+	if (ret)
+		goto out_put_req;
 
-	return rc;
+	ceph_osdc_start_request(osdc, req, false);
+	linger_cancel(lreq);
+	linger_put(lreq);
+	ret = wait_request_timeout(req, opts->mount_timeout);
+
+out_put_req:
+	ceph_osdc_put_request(req);
+	return ret;
 }
-EXPORT_SYMBOL(ceph_osdc_start_request);
+EXPORT_SYMBOL(ceph_osdc_unwatch);
 
-/*
- * Unregister a registered request.  The request is not completed (i.e.
- * no callbacks or wakeups) - higher layers are supposed to know what
- * they are canceling.
- */
-void ceph_osdc_cancel_request(struct ceph_osd_request *req)
+static int osd_req_op_notify_ack_init(struct ceph_osd_request *req, int which,
+				      u64 notify_id, u64 cookie, void *payload,
+				      size_t payload_len)
 {
-	struct ceph_osd_client *osdc = req->r_osdc;
+	struct ceph_osd_req_op *op;
+	struct ceph_pagelist *pl;
+	int ret;
+
+	op = _osd_req_op_init(req, which, CEPH_OSD_OP_NOTIFY_ACK, 0);
+
+	pl = kmalloc(sizeof(*pl), GFP_NOIO);
+	if (!pl)
+		return -ENOMEM;
 
-	mutex_lock(&osdc->request_mutex);
-	if (req->r_linger)
-		__unregister_linger_request(osdc, req);
-	__unregister_request(osdc, req);
-	mutex_unlock(&osdc->request_mutex);
+	ceph_pagelist_init(pl);
+	ret = ceph_pagelist_encode_64(pl, notify_id);
+	ret |= ceph_pagelist_encode_64(pl, cookie);
+	if (payload) {
+		ret |= ceph_pagelist_encode_32(pl, payload_len);
+		ret |= ceph_pagelist_append(pl, payload, payload_len);
+	} else {
+		ret |= ceph_pagelist_encode_32(pl, 0);
+	}
+	if (ret) {
+		ceph_pagelist_release(pl);
+		return -ENOMEM;
+	}
 
-	dout("%s %p tid %llu canceled\n", __func__, req, req->r_tid);
+	ceph_osd_data_pagelist_init(&op->notify_ack.request_data, pl);
+	op->indata_len = pl->length;
+	return 0;
 }
-EXPORT_SYMBOL(ceph_osdc_cancel_request);
 
-/*
- * wait for a request to complete
- */
-int ceph_osdc_wait_request(struct ceph_osd_client *osdc,
-			   struct ceph_osd_request *req)
+int ceph_osdc_notify_ack(struct ceph_osd_client *osdc,
+			 struct ceph_object_id *oid,
+			 struct ceph_object_locator *oloc,
+			 u64 notify_id,
+			 u64 cookie,
+			 void *payload,
+			 size_t payload_len)
+{
+	struct ceph_osd_request *req;
+	int ret;
+
+	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_NOIO);
+	if (!req)
+		return -ENOMEM;
+
+	ceph_oid_copy(&req->r_base_oid, oid);
+	ceph_oloc_copy(&req->r_base_oloc, oloc);
+	req->r_flags = CEPH_OSD_FLAG_READ;
+
+	ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
+	if (ret)
+		goto out_put_req;
+
+	ret = osd_req_op_notify_ack_init(req, 0, notify_id, cookie, payload,
+					 payload_len);
+	if (ret)
+		goto out_put_req;
+
+	ceph_osdc_start_request(osdc, req, false);
+	ret = ceph_osdc_wait_request(osdc, req);
+
+out_put_req:
+	ceph_osdc_put_request(req);
+	return ret;
+}
+EXPORT_SYMBOL(ceph_osdc_notify_ack);
+
+static int osd_req_op_notify_init(struct ceph_osd_request *req, int which,
+				  u64 cookie, u32 prot_ver, u32 timeout,
+				  void *payload, size_t payload_len)
 {
-	int rc;
+	struct ceph_osd_req_op *op;
+	struct ceph_pagelist *pl;
+	int ret;
 
-	dout("%s %p tid %llu\n", __func__, req, req->r_tid);
+	op = _osd_req_op_init(req, which, CEPH_OSD_OP_NOTIFY, 0);
+	op->notify.cookie = cookie;
 
-	rc = wait_for_completion_interruptible(&req->r_completion);
-	if (rc < 0) {
-		dout("%s %p tid %llu interrupted\n", __func__, req, req->r_tid);
-		ceph_osdc_cancel_request(req);
-		complete_request(req);
-		return rc;
+	pl = kmalloc(sizeof(*pl), GFP_NOIO);
+	if (!pl)
+		return -ENOMEM;
+
+	ceph_pagelist_init(pl);
+	ret = ceph_pagelist_encode_32(pl, 1); /* prot_ver */
+	ret |= ceph_pagelist_encode_32(pl, timeout);
+	ret |= ceph_pagelist_encode_32(pl, payload_len);
+	ret |= ceph_pagelist_append(pl, payload, payload_len);
+	if (ret) {
+		ceph_pagelist_release(pl);
+		return -ENOMEM;
 	}
 
-	dout("%s %p tid %llu result %d\n", __func__, req, req->r_tid,
-	     req->r_result);
-	return req->r_result;
+	ceph_osd_data_pagelist_init(&op->notify.request_data, pl);
+	op->indata_len = pl->length;
+	return 0;
 }
-EXPORT_SYMBOL(ceph_osdc_wait_request);
 
 /*
- * sync - wait for all in-flight requests to flush.  avoid starvation.
+ * @timeout: in seconds
+ *
+ * @preply_{pages,len} are initialized both on success and error.
+ * The caller is responsible for:
+ *
+ *     ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len))
  */
-void ceph_osdc_sync(struct ceph_osd_client *osdc)
+int ceph_osdc_notify(struct ceph_osd_client *osdc,
+		     struct ceph_object_id *oid,
+		     struct ceph_object_locator *oloc,
+		     void *payload,
+		     size_t payload_len,
+		     u32 timeout,
+		     struct page ***preply_pages,
+		     size_t *preply_len)
 {
-	struct ceph_osd_request *req;
-	u64 last_tid, next_tid = 0;
+	struct ceph_osd_linger_request *lreq;
+	struct page **pages;
+	int ret;
 
-	mutex_lock(&osdc->request_mutex);
-	last_tid = osdc->last_tid;
-	while (1) {
-		req = __lookup_request_ge(osdc, next_tid);
-		if (!req)
-			break;
-		if (req->r_tid > last_tid)
-			break;
+	WARN_ON(!timeout);
+	if (preply_pages) {
+		*preply_pages = NULL;
+		*preply_len = 0;
+	}
 
-		next_tid = req->r_tid + 1;
-		if ((req->r_flags & CEPH_OSD_FLAG_WRITE) == 0)
-			continue;
+	lreq = linger_alloc(osdc);
+	if (!lreq)
+		return -ENOMEM;
 
-		ceph_osdc_get_request(req);
-		mutex_unlock(&osdc->request_mutex);
-		dout("sync waiting on tid %llu (last is %llu)\n",
-		     req->r_tid, last_tid);
-		wait_for_completion(&req->r_safe_completion);
-		mutex_lock(&osdc->request_mutex);
-		ceph_osdc_put_request(req);
+	lreq->preply_pages = preply_pages;
+	lreq->preply_len = preply_len;
+
+	ceph_oid_copy(&lreq->t.base_oid, oid);
+	ceph_oloc_copy(&lreq->t.base_oloc, oloc);
+	lreq->t.flags = CEPH_OSD_FLAG_READ;
+
+	lreq->reg_req = alloc_linger_request(lreq);
+	if (!lreq->reg_req) {
+		ret = -ENOMEM;
+		goto out_put_lreq;
 	}
-	mutex_unlock(&osdc->request_mutex);
-	dout("sync done (thru tid %llu)\n", last_tid);
+
+	/* for notify_id */
+	pages = ceph_alloc_page_vector(1, GFP_NOIO);
+	if (IS_ERR(pages)) {
+		ret = PTR_ERR(pages);
+		goto out_put_lreq;
+	}
+
+	down_write(&osdc->lock);
+	linger_register(lreq); /* before osd_req_op_* */
+	ret = osd_req_op_notify_init(lreq->reg_req, 0, lreq->linger_id, 1,
+				     timeout, payload, payload_len);
+	if (ret) {
+		linger_unregister(lreq);
+		up_write(&osdc->lock);
+		ceph_release_page_vector(pages, 1);
+		goto out_put_lreq;
+	}
+	ceph_osd_data_pages_init(osd_req_op_data(lreq->reg_req, 0, notify,
+						 response_data),
+				 pages, PAGE_SIZE, 0, false, true);
+	linger_submit(lreq);
+	up_write(&osdc->lock);
+
+	ret = linger_reg_commit_wait(lreq);
+	if (!ret)
+		ret = linger_notify_finish_wait(lreq);
+	else
+		dout("lreq %p failed to initiate notify %d\n", lreq, ret);
+
+	linger_cancel(lreq);
+out_put_lreq:
+	linger_put(lreq);
+	return ret;
+}
+EXPORT_SYMBOL(ceph_osdc_notify);
+
+/*
+ * Return the number of milliseconds since the watch was last
+ * confirmed, or an error.  If there is an error, the watch is no
+ * longer valid, and should be destroyed with ceph_osdc_unwatch().
+ */
+int ceph_osdc_watch_check(struct ceph_osd_client *osdc,
+			  struct ceph_osd_linger_request *lreq)
+{
+	unsigned long stamp, age;
+	int ret;
+
+	down_read(&osdc->lock);
+	mutex_lock(&lreq->lock);
+	stamp = lreq->watch_valid_thru;
+	if (!list_empty(&lreq->pending_lworks)) {
+		struct linger_work *lwork =
+		    list_first_entry(&lreq->pending_lworks,
+				     struct linger_work,
+				     pending_item);
+
+		if (time_before(lwork->queued_stamp, stamp))
+			stamp = lwork->queued_stamp;
+	}
+	age = jiffies - stamp;
+	dout("%s lreq %p linger_id %llu age %lu last_error %d\n", __func__,
+	     lreq, lreq->linger_id, age, lreq->last_error);
+	/* we are truncating to msecs, so return a safe upper bound */
+	ret = lreq->last_error ?: 1 + jiffies_to_msecs(age);
+
+	mutex_unlock(&lreq->lock);
+	up_read(&osdc->lock);
+	return ret;
 }
-EXPORT_SYMBOL(ceph_osdc_sync);
 
 /*
  * Call all pending notify callbacks - for use after a watch is
@@ -2646,6 +3868,13 @@ void ceph_osdc_flush_notifies(struct ceph_osd_client *osdc)
 }
 EXPORT_SYMBOL(ceph_osdc_flush_notifies);
 
+void ceph_osdc_maybe_request_map(struct ceph_osd_client *osdc)
+{
+	down_read(&osdc->lock);
+	maybe_request_map(osdc);
+	up_read(&osdc->lock);
+}
+EXPORT_SYMBOL(ceph_osdc_maybe_request_map);
 
 /*
  * init, shutdown
@@ -2656,43 +3885,35 @@ int ceph_osdc_init(struct ceph_osd_client *osdc, struct ceph_client *client)
 
 	dout("init\n");
 	osdc->client = client;
-	osdc->osdmap = NULL;
-	init_rwsem(&osdc->map_sem);
-	init_completion(&osdc->map_waiters);
-	osdc->last_requested_map = 0;
-	mutex_init(&osdc->request_mutex);
-	osdc->last_tid = 0;
+	init_rwsem(&osdc->lock);
 	osdc->osds = RB_ROOT;
 	INIT_LIST_HEAD(&osdc->osd_lru);
-	osdc->requests = RB_ROOT;
-	INIT_LIST_HEAD(&osdc->req_lru);
-	INIT_LIST_HEAD(&osdc->req_unsent);
-	INIT_LIST_HEAD(&osdc->req_notarget);
-	INIT_LIST_HEAD(&osdc->req_linger);
-	osdc->num_requests = 0;
+	spin_lock_init(&osdc->osd_lru_lock);
+	osd_init(&osdc->homeless_osd);
+	osdc->homeless_osd.o_osdc = osdc;
+	osdc->homeless_osd.o_osd = CEPH_HOMELESS_OSD;
+	osdc->linger_requests = RB_ROOT;
+	osdc->map_checks = RB_ROOT;
+	osdc->linger_map_checks = RB_ROOT;
 	INIT_DELAYED_WORK(&osdc->timeout_work, handle_timeout);
 	INIT_DELAYED_WORK(&osdc->osds_timeout_work, handle_osds_timeout);
-	spin_lock_init(&osdc->event_lock);
-	osdc->event_tree = RB_ROOT;
-	osdc->event_count = 0;
-
-	schedule_delayed_work(&osdc->osds_timeout_work,
-	    round_jiffies_relative(osdc->client->options->osd_idle_ttl));
 
 	err = -ENOMEM;
+	osdc->osdmap = ceph_osdmap_alloc();
+	if (!osdc->osdmap)
+		goto out;
+
 	osdc->req_mempool = mempool_create_slab_pool(10,
 						     ceph_osd_request_cache);
 	if (!osdc->req_mempool)
-		goto out;
+		goto out_map;
 
 	err = ceph_msgpool_init(&osdc->msgpool_op, CEPH_MSG_OSD_OP,
-				OSD_OP_FRONT_LEN, 10, true,
-				"osd_op");
+				PAGE_SIZE, 10, true, "osd_op");
 	if (err < 0)
 		goto out_mempool;
 	err = ceph_msgpool_init(&osdc->msgpool_op_reply, CEPH_MSG_OSD_OPREPLY,
-				OSD_OPREPLY_FRONT_LEN, 10, true,
-				"osd_op_reply");
+				PAGE_SIZE, 10, true, "osd_op_reply");
 	if (err < 0)
 		goto out_msgpool;
 
@@ -2701,6 +3922,11 @@ int ceph_osdc_init(struct ceph_osd_client *osdc, struct ceph_client *client)
 	if (!osdc->notify_wq)
 		goto out_msgpool_reply;
 
+	schedule_delayed_work(&osdc->timeout_work,
+			      osdc->client->options->osd_keepalive_timeout);
+	schedule_delayed_work(&osdc->osds_timeout_work,
+	    round_jiffies_relative(osdc->client->options->osd_idle_ttl));
+
 	return 0;
 
 out_msgpool_reply:
@@ -2709,6 +3935,8 @@ out_msgpool:
 	ceph_msgpool_destroy(&osdc->msgpool_op);
 out_mempool:
 	mempool_destroy(osdc->req_mempool);
+out_map:
+	ceph_osdmap_destroy(osdc->osdmap);
 out:
 	return err;
 }
@@ -2719,11 +3947,25 @@ void ceph_osdc_stop(struct ceph_osd_client *osdc)
 	destroy_workqueue(osdc->notify_wq);
 	cancel_delayed_work_sync(&osdc->timeout_work);
 	cancel_delayed_work_sync(&osdc->osds_timeout_work);
-	if (osdc->osdmap) {
-		ceph_osdmap_destroy(osdc->osdmap);
-		osdc->osdmap = NULL;
+
+	down_write(&osdc->lock);
+	while (!RB_EMPTY_ROOT(&osdc->osds)) {
+		struct ceph_osd *osd = rb_entry(rb_first(&osdc->osds),
+						struct ceph_osd, o_node);
+		close_osd(osd);
 	}
-	remove_all_osds(osdc);
+	up_write(&osdc->lock);
+	WARN_ON(atomic_read(&osdc->homeless_osd.o_ref) != 1);
+	osd_cleanup(&osdc->homeless_osd);
+
+	WARN_ON(!list_empty(&osdc->osd_lru));
+	WARN_ON(!RB_EMPTY_ROOT(&osdc->linger_requests));
+	WARN_ON(!RB_EMPTY_ROOT(&osdc->map_checks));
+	WARN_ON(!RB_EMPTY_ROOT(&osdc->linger_map_checks));
+	WARN_ON(atomic_read(&osdc->num_requests));
+	WARN_ON(atomic_read(&osdc->num_homeless));
+
+	ceph_osdmap_destroy(osdc->osdmap);
 	mempool_destroy(osdc->req_mempool);
 	ceph_msgpool_destroy(&osdc->msgpool_op);
 	ceph_msgpool_destroy(&osdc->msgpool_op_reply);
@@ -2752,15 +3994,12 @@ int ceph_osdc_readpages(struct ceph_osd_client *osdc,
 		return PTR_ERR(req);
 
 	/* it may be a short read due to an object boundary */
-
 	osd_req_op_extent_osd_data_pages(req, 0,
 				pages, *plen, page_align, false, false);
 
 	dout("readpages  final extent is %llu~%llu (%llu bytes align %d)\n",
 	     off, *plen, *plen, page_align);
 
-	ceph_osdc_build_request(req, off, NULL, vino.snap, NULL);
-
 	rc = ceph_osdc_start_request(osdc, req, false);
 	if (!rc)
 		rc = ceph_osdc_wait_request(osdc, req);
@@ -2786,7 +4025,6 @@ int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
 	int rc = 0;
 	int page_align = off & ~PAGE_MASK;
 
-	BUG_ON(vino.snap != CEPH_NOSNAP);	/* snapshots aren't writeable */
 	req = ceph_osdc_new_request(osdc, layout, vino, off, &len, 0, 1,
 				    CEPH_OSD_OP_WRITE,
 				    CEPH_OSD_FLAG_ONDISK | CEPH_OSD_FLAG_WRITE,
@@ -2800,8 +4038,7 @@ int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
 				false, false);
 	dout("writepages %llu~%llu (%llu bytes)\n", off, len, len);
 
-	ceph_osdc_build_request(req, off, snapc, CEPH_NOSNAP, mtime);
-
+	req->r_mtime = *mtime;
 	rc = ceph_osdc_start_request(osdc, req, true);
 	if (!rc)
 		rc = ceph_osdc_wait_request(osdc, req);
@@ -2841,19 +4078,15 @@ EXPORT_SYMBOL(ceph_osdc_cleanup);
 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
 {
 	struct ceph_osd *osd = con->private;
-	struct ceph_osd_client *osdc;
+	struct ceph_osd_client *osdc = osd->o_osdc;
 	int type = le16_to_cpu(msg->hdr.type);
 
-	if (!osd)
-		goto out;
-	osdc = osd->o_osdc;
-
 	switch (type) {
 	case CEPH_MSG_OSD_MAP:
 		ceph_osdc_handle_map(osdc, msg);
 		break;
 	case CEPH_MSG_OSD_OPREPLY:
-		handle_reply(osdc, msg);
+		handle_reply(osd, msg);
 		break;
 	case CEPH_MSG_WATCH_NOTIFY:
 		handle_watch_notify(osdc, msg);
@@ -2863,7 +4096,7 @@ static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
 		pr_err("received unknown message type %d %s\n", type,
 		       ceph_msg_type_name(type));
 	}
-out:
+
 	ceph_msg_put(msg);
 }
 
@@ -2878,21 +4111,27 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
 {
 	struct ceph_osd *osd = con->private;
 	struct ceph_osd_client *osdc = osd->o_osdc;
-	struct ceph_msg *m;
+	struct ceph_msg *m = NULL;
 	struct ceph_osd_request *req;
 	int front_len = le32_to_cpu(hdr->front_len);
 	int data_len = le32_to_cpu(hdr->data_len);
-	u64 tid;
+	u64 tid = le64_to_cpu(hdr->tid);
 
-	tid = le64_to_cpu(hdr->tid);
-	mutex_lock(&osdc->request_mutex);
-	req = __lookup_request(osdc, tid);
+	down_read(&osdc->lock);
+	if (!osd_registered(osd)) {
+		dout("%s osd%d unknown, skipping\n", __func__, osd->o_osd);
+		*skip = 1;
+		goto out_unlock_osdc;
+	}
+	WARN_ON(osd->o_osd != le64_to_cpu(hdr->src.num));
+
+	mutex_lock(&osd->lock);
+	req = lookup_request(&osd->o_requests, tid);
 	if (!req) {
 		dout("%s osd%d tid %llu unknown, skipping\n", __func__,
 		     osd->o_osd, tid);
-		m = NULL;
 		*skip = 1;
-		goto out;
+		goto out_unlock_session;
 	}
 
 	ceph_msg_revoke_incoming(req->r_reply);
@@ -2904,7 +4143,7 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
 		m = ceph_msg_new(CEPH_MSG_OSD_OPREPLY, front_len, GFP_NOFS,
 				 false);
 		if (!m)
-			goto out;
+			goto out_unlock_session;
 		ceph_msg_put(req->r_reply);
 		req->r_reply = m;
 	}
@@ -2915,14 +4154,49 @@ static struct ceph_msg *get_reply(struct ceph_connection *con,
 			req->r_reply->data_length);
 		m = NULL;
 		*skip = 1;
-		goto out;
+		goto out_unlock_session;
 	}
 
 	m = ceph_msg_get(req->r_reply);
 	dout("get_reply tid %lld %p\n", tid, m);
 
-out:
-	mutex_unlock(&osdc->request_mutex);
+out_unlock_session:
+	mutex_unlock(&osd->lock);
+out_unlock_osdc:
+	up_read(&osdc->lock);
+	return m;
+}
+
+/*
+ * TODO: switch to a msg-owned pagelist
+ */
+static struct ceph_msg *alloc_msg_with_page_vector(struct ceph_msg_header *hdr)
+{
+	struct ceph_msg *m;
+	int type = le16_to_cpu(hdr->type);
+	u32 front_len = le32_to_cpu(hdr->front_len);
+	u32 data_len = le32_to_cpu(hdr->data_len);
+
+	m = ceph_msg_new(type, front_len, GFP_NOIO, false);
+	if (!m)
+		return NULL;
+
+	if (data_len) {
+		struct page **pages;
+		struct ceph_osd_data osd_data;
+
+		pages = ceph_alloc_page_vector(calc_pages_for(0, data_len),
+					       GFP_NOIO);
+		if (!pages) {
+			ceph_msg_put(m);
+			return NULL;
+		}
+
+		ceph_osd_data_pages_init(&osd_data, pages, data_len, 0, false,
+					 false);
+		ceph_osdc_msg_data_add(m, &osd_data);
+	}
+
 	return m;
 }
 
@@ -2932,18 +4206,17 @@ static struct ceph_msg *alloc_msg(struct ceph_connection *con,
 {
 	struct ceph_osd *osd = con->private;
 	int type = le16_to_cpu(hdr->type);
-	int front = le32_to_cpu(hdr->front_len);
 
 	*skip = 0;
 	switch (type) {
 	case CEPH_MSG_OSD_MAP:
 	case CEPH_MSG_WATCH_NOTIFY:
-		return ceph_msg_new(type, front, GFP_NOFS, false);
+		return alloc_msg_with_page_vector(hdr);
 	case CEPH_MSG_OSD_OPREPLY:
 		return get_reply(con, hdr, skip);
 	default:
-		pr_info("alloc_msg unexpected msg type %d from osd%d\n", type,
-			osd->o_osd);
+		pr_warn("%s osd%d unknown msg type %d, skipping\n", __func__,
+			osd->o_osd, type);
 		*skip = 1;
 		return NULL;
 	}
@@ -3047,5 +4320,5 @@ static const struct ceph_connection_operations osd_con_ops = {
 	.alloc_msg = alloc_msg,
 	.sign_message = osd_sign_message,
 	.check_message_signature = osd_check_message_signature,
-	.fault = osd_reset,
+	.fault = osd_fault,
 };
diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c
index 243574c8c..7e480bf75 100644
--- a/net/ceph/osdmap.c
+++ b/net/ceph/osdmap.c
@@ -380,23 +380,24 @@ bad:
 	return ERR_PTR(err);
 }
 
-/*
- * rbtree of pg_mapping for handling pg_temp (explicit mapping of pgid
- * to a set of osds) and primary_temp (explicit primary setting)
- */
-static int pgid_cmp(struct ceph_pg l, struct ceph_pg r)
+int ceph_pg_compare(const struct ceph_pg *lhs, const struct ceph_pg *rhs)
 {
-	if (l.pool < r.pool)
+	if (lhs->pool < rhs->pool)
 		return -1;
-	if (l.pool > r.pool)
+	if (lhs->pool > rhs->pool)
 		return 1;
-	if (l.seed < r.seed)
+	if (lhs->seed < rhs->seed)
 		return -1;
-	if (l.seed > r.seed)
+	if (lhs->seed > rhs->seed)
 		return 1;
+
 	return 0;
 }
 
+/*
+ * rbtree of pg_mapping for handling pg_temp (explicit mapping of pgid
+ * to a set of osds) and primary_temp (explicit primary setting)
+ */
 static int __insert_pg_mapping(struct ceph_pg_mapping *new,
 			       struct rb_root *root)
 {
@@ -409,7 +410,7 @@ static int __insert_pg_mapping(struct ceph_pg_mapping *new,
 	while (*p) {
 		parent = *p;
 		pg = rb_entry(parent, struct ceph_pg_mapping, node);
-		c = pgid_cmp(new->pgid, pg->pgid);
+		c = ceph_pg_compare(&new->pgid, &pg->pgid);
 		if (c < 0)
 			p = &(*p)->rb_left;
 		else if (c > 0)
@@ -432,7 +433,7 @@ static struct ceph_pg_mapping *__lookup_pg_mapping(struct rb_root *root,
 
 	while (n) {
 		pg = rb_entry(n, struct ceph_pg_mapping, node);
-		c = pgid_cmp(pgid, pg->pgid);
+		c = ceph_pg_compare(&pgid, &pg->pgid);
 		if (c < 0) {
 			n = n->rb_left;
 		} else if (c > 0) {
@@ -596,7 +597,9 @@ static int decode_pool(void **p, void *end, struct ceph_pg_pool_info *pi)
 	*p += 4;  /* skip crash_replay_interval */
 
 	if (ev >= 7)
-		*p += 1;  /* skip min_size */
+		pi->min_size = ceph_decode_8(p);
+	else
+		pi->min_size = pi->size - pi->size / 2;
 
 	if (ev >= 8)
 		*p += 8 + 8;  /* skip quota_max_* */
@@ -616,6 +619,50 @@ static int decode_pool(void **p, void *end, struct ceph_pg_pool_info *pi)
 		pi->write_tier = -1;
 	}
 
+	if (ev >= 10) {
+		/* skip properties */
+		num = ceph_decode_32(p);
+		while (num--) {
+			len = ceph_decode_32(p);
+			*p += len; /* key */
+			len = ceph_decode_32(p);
+			*p += len; /* val */
+		}
+	}
+
+	if (ev >= 11) {
+		/* skip hit_set_params */
+		*p += 1 + 1; /* versions */
+		len = ceph_decode_32(p);
+		*p += len;
+
+		*p += 4; /* skip hit_set_period */
+		*p += 4; /* skip hit_set_count */
+	}
+
+	if (ev >= 12)
+		*p += 4; /* skip stripe_width */
+
+	if (ev >= 13) {
+		*p += 8; /* skip target_max_bytes */
+		*p += 8; /* skip target_max_objects */
+		*p += 4; /* skip cache_target_dirty_ratio_micro */
+		*p += 4; /* skip cache_target_full_ratio_micro */
+		*p += 4; /* skip cache_min_flush_age */
+		*p += 4; /* skip cache_min_evict_age */
+	}
+
+	if (ev >=  14) {
+		/* skip erasure_code_profile */
+		len = ceph_decode_32(p);
+		*p += len;
+	}
+
+	if (ev >= 15)
+		pi->last_force_request_resend = ceph_decode_32(p);
+	else
+		pi->last_force_request_resend = 0;
+
 	/* ignore the rest */
 
 	*p = pool_end;
@@ -660,6 +707,23 @@ bad:
 /*
  * osd map
  */
+struct ceph_osdmap *ceph_osdmap_alloc(void)
+{
+	struct ceph_osdmap *map;
+
+	map = kzalloc(sizeof(*map), GFP_NOIO);
+	if (!map)
+		return NULL;
+
+	map->pg_pools = RB_ROOT;
+	map->pool_max = -1;
+	map->pg_temp = RB_ROOT;
+	map->primary_temp = RB_ROOT;
+	mutex_init(&map->crush_scratch_mutex);
+
+	return map;
+}
+
 void ceph_osdmap_destroy(struct ceph_osdmap *map)
 {
 	dout("osdmap_destroy %p\n", map);
@@ -1183,14 +1247,10 @@ struct ceph_osdmap *ceph_osdmap_decode(void **p, void *end)
 	struct ceph_osdmap *map;
 	int ret;
 
-	map = kzalloc(sizeof(*map), GFP_NOFS);
+	map = ceph_osdmap_alloc();
 	if (!map)
 		return ERR_PTR(-ENOMEM);
 
-	map->pg_temp = RB_ROOT;
-	map->primary_temp = RB_ROOT;
-	mutex_init(&map->crush_scratch_mutex);
-
 	ret = osdmap_decode(p, end, map);
 	if (ret) {
 		ceph_osdmap_destroy(map);
@@ -1201,11 +1261,119 @@ struct ceph_osdmap *ceph_osdmap_decode(void **p, void *end)
 }
 
 /*
+ * Encoding order is (new_up_client, new_state, new_weight).  Need to
+ * apply in the (new_weight, new_state, new_up_client) order, because
+ * an incremental map may look like e.g.
+ *
+ *     new_up_client: { osd=6, addr=... } # set osd_state and addr
+ *     new_state: { osd=6, xorstate=EXISTS } # clear osd_state
+ */
+static int decode_new_up_state_weight(void **p, void *end,
+				      struct ceph_osdmap *map)
+{
+	void *new_up_client;
+	void *new_state;
+	void *new_weight_end;
+	u32 len;
+
+	new_up_client = *p;
+	ceph_decode_32_safe(p, end, len, e_inval);
+	len *= sizeof(u32) + sizeof(struct ceph_entity_addr);
+	ceph_decode_need(p, end, len, e_inval);
+	*p += len;
+
+	new_state = *p;
+	ceph_decode_32_safe(p, end, len, e_inval);
+	len *= sizeof(u32) + sizeof(u8);
+	ceph_decode_need(p, end, len, e_inval);
+	*p += len;
+
+	/* new_weight */
+	ceph_decode_32_safe(p, end, len, e_inval);
+	while (len--) {
+		s32 osd;
+		u32 w;
+
+		ceph_decode_need(p, end, 2*sizeof(u32), e_inval);
+		osd = ceph_decode_32(p);
+		w = ceph_decode_32(p);
+		BUG_ON(osd >= map->max_osd);
+		pr_info("osd%d weight 0x%x %s\n", osd, w,
+		     w == CEPH_OSD_IN ? "(in)" :
+		     (w == CEPH_OSD_OUT ? "(out)" : ""));
+		map->osd_weight[osd] = w;
+
+		/*
+		 * If we are marking in, set the EXISTS, and clear the
+		 * AUTOOUT and NEW bits.
+		 */
+		if (w) {
+			map->osd_state[osd] |= CEPH_OSD_EXISTS;
+			map->osd_state[osd] &= ~(CEPH_OSD_AUTOOUT |
+						 CEPH_OSD_NEW);
+		}
+	}
+	new_weight_end = *p;
+
+	/* new_state (up/down) */
+	*p = new_state;
+	len = ceph_decode_32(p);
+	while (len--) {
+		s32 osd;
+		u8 xorstate;
+		int ret;
+
+		osd = ceph_decode_32(p);
+		xorstate = ceph_decode_8(p);
+		if (xorstate == 0)
+			xorstate = CEPH_OSD_UP;
+		BUG_ON(osd >= map->max_osd);
+		if ((map->osd_state[osd] & CEPH_OSD_UP) &&
+		    (xorstate & CEPH_OSD_UP))
+			pr_info("osd%d down\n", osd);
+		if ((map->osd_state[osd] & CEPH_OSD_EXISTS) &&
+		    (xorstate & CEPH_OSD_EXISTS)) {
+			pr_info("osd%d does not exist\n", osd);
+			map->osd_weight[osd] = CEPH_OSD_IN;
+			ret = set_primary_affinity(map, osd,
+						   CEPH_OSD_DEFAULT_PRIMARY_AFFINITY);
+			if (ret)
+				return ret;
+			memset(map->osd_addr + osd, 0, sizeof(*map->osd_addr));
+			map->osd_state[osd] = 0;
+		} else {
+			map->osd_state[osd] ^= xorstate;
+		}
+	}
+
+	/* new_up_client */
+	*p = new_up_client;
+	len = ceph_decode_32(p);
+	while (len--) {
+		s32 osd;
+		struct ceph_entity_addr addr;
+
+		osd = ceph_decode_32(p);
+		ceph_decode_copy(p, &addr, sizeof(addr));
+		ceph_decode_addr(&addr);
+		BUG_ON(osd >= map->max_osd);
+		pr_info("osd%d up\n", osd);
+		map->osd_state[osd] |= CEPH_OSD_EXISTS | CEPH_OSD_UP;
+		map->osd_addr[osd] = addr;
+	}
+
+	*p = new_weight_end;
+	return 0;
+
+e_inval:
+	return -EINVAL;
+}
+
+/*
  * decode and apply an incremental map update.
  */
 struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
-					     struct ceph_osdmap *map,
-					     struct ceph_messenger *msgr)
+					     struct ceph_osdmap *map)
 {
 	struct crush_map *newcrush = NULL;
 	struct ceph_fsid fsid;
@@ -1299,49 +1467,10 @@ struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
 			__remove_pg_pool(&map->pg_pools, pi);
 	}
 
-	/* new_up */
-	ceph_decode_32_safe(p, end, len, e_inval);
-	while (len--) {
-		u32 osd;
-		struct ceph_entity_addr addr;
-		ceph_decode_32_safe(p, end, osd, e_inval);
-		ceph_decode_copy_safe(p, end, &addr, sizeof(addr), e_inval);
-		ceph_decode_addr(&addr);
-		pr_info("osd%d up\n", osd);
-		BUG_ON(osd >= map->max_osd);
-		map->osd_state[osd] |= CEPH_OSD_UP | CEPH_OSD_EXISTS;
-		map->osd_addr[osd] = addr;
-	}
-
-	/* new_state */
-	ceph_decode_32_safe(p, end, len, e_inval);
-	while (len--) {
-		u32 osd;
-		u8 xorstate;
-		ceph_decode_32_safe(p, end, osd, e_inval);
-		xorstate = **(u8 **)p;
-		(*p)++;  /* clean flag */
-		if (xorstate == 0)
-			xorstate = CEPH_OSD_UP;
-		if (xorstate & CEPH_OSD_UP)
-			pr_info("osd%d down\n", osd);
-		if (osd < map->max_osd)
-			map->osd_state[osd] ^= xorstate;
-	}
-
-	/* new_weight */
-	ceph_decode_32_safe(p, end, len, e_inval);
-	while (len--) {
-		u32 osd, off;
-		ceph_decode_need(p, end, sizeof(u32)*2, e_inval);
-		osd = ceph_decode_32(p);
-		off = ceph_decode_32(p);
-		pr_info("osd%d weight 0x%x %s\n", osd, off,
-		     off == CEPH_OSD_IN ? "(in)" :
-		     (off == CEPH_OSD_OUT ? "(out)" : ""));
-		if (osd < map->max_osd)
-			map->osd_weight[osd] = off;
-	}
+	/* new_up_client, new_state, new_weight */
+	err = decode_new_up_state_weight(p, end, map);
+	if (err)
+		goto bad;
 
 	/* new_pg_temp */
 	err = decode_new_pg_temp(p, end, map);
@@ -1381,8 +1510,252 @@ bad:
 	return ERR_PTR(err);
 }
 
+void ceph_oid_copy(struct ceph_object_id *dest,
+		   const struct ceph_object_id *src)
+{
+	WARN_ON(!ceph_oid_empty(dest));
+
+	if (src->name != src->inline_name) {
+		/* very rare, see ceph_object_id definition */
+		dest->name = kmalloc(src->name_len + 1,
+				     GFP_NOIO | __GFP_NOFAIL);
+	}
 
+	memcpy(dest->name, src->name, src->name_len + 1);
+	dest->name_len = src->name_len;
+}
+EXPORT_SYMBOL(ceph_oid_copy);
 
+static __printf(2, 0)
+int oid_printf_vargs(struct ceph_object_id *oid, const char *fmt, va_list ap)
+{
+	int len;
+
+	WARN_ON(!ceph_oid_empty(oid));
+
+	len = vsnprintf(oid->inline_name, sizeof(oid->inline_name), fmt, ap);
+	if (len >= sizeof(oid->inline_name))
+		return len;
+
+	oid->name_len = len;
+	return 0;
+}
+
+/*
+ * If oid doesn't fit into inline buffer, BUG.
+ */
+void ceph_oid_printf(struct ceph_object_id *oid, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	BUG_ON(oid_printf_vargs(oid, fmt, ap));
+	va_end(ap);
+}
+EXPORT_SYMBOL(ceph_oid_printf);
+
+static __printf(3, 0)
+int oid_aprintf_vargs(struct ceph_object_id *oid, gfp_t gfp,
+		      const char *fmt, va_list ap)
+{
+	va_list aq;
+	int len;
+
+	va_copy(aq, ap);
+	len = oid_printf_vargs(oid, fmt, aq);
+	va_end(aq);
+
+	if (len) {
+		char *external_name;
+
+		external_name = kmalloc(len + 1, gfp);
+		if (!external_name)
+			return -ENOMEM;
+
+		oid->name = external_name;
+		WARN_ON(vsnprintf(oid->name, len + 1, fmt, ap) != len);
+		oid->name_len = len;
+	}
+
+	return 0;
+}
+
+/*
+ * If oid doesn't fit into inline buffer, allocate.
+ */
+int ceph_oid_aprintf(struct ceph_object_id *oid, gfp_t gfp,
+		     const char *fmt, ...)
+{
+	va_list ap;
+	int ret;
+
+	va_start(ap, fmt);
+	ret = oid_aprintf_vargs(oid, gfp, fmt, ap);
+	va_end(ap);
+
+	return ret;
+}
+EXPORT_SYMBOL(ceph_oid_aprintf);
+
+void ceph_oid_destroy(struct ceph_object_id *oid)
+{
+	if (oid->name != oid->inline_name)
+		kfree(oid->name);
+}
+EXPORT_SYMBOL(ceph_oid_destroy);
+
+/*
+ * osds only
+ */
+static bool __osds_equal(const struct ceph_osds *lhs,
+			 const struct ceph_osds *rhs)
+{
+	if (lhs->size == rhs->size &&
+	    !memcmp(lhs->osds, rhs->osds, rhs->size * sizeof(rhs->osds[0])))
+		return true;
+
+	return false;
+}
+
+/*
+ * osds + primary
+ */
+static bool osds_equal(const struct ceph_osds *lhs,
+		       const struct ceph_osds *rhs)
+{
+	if (__osds_equal(lhs, rhs) &&
+	    lhs->primary == rhs->primary)
+		return true;
+
+	return false;
+}
+
+static bool osds_valid(const struct ceph_osds *set)
+{
+	/* non-empty set */
+	if (set->size > 0 && set->primary >= 0)
+		return true;
+
+	/* empty can_shift_osds set */
+	if (!set->size && set->primary == -1)
+		return true;
+
+	/* empty !can_shift_osds set - all NONE */
+	if (set->size > 0 && set->primary == -1) {
+		int i;
+
+		for (i = 0; i < set->size; i++) {
+			if (set->osds[i] != CRUSH_ITEM_NONE)
+				break;
+		}
+		if (i == set->size)
+			return true;
+	}
+
+	return false;
+}
+
+void ceph_osds_copy(struct ceph_osds *dest, const struct ceph_osds *src)
+{
+	memcpy(dest->osds, src->osds, src->size * sizeof(src->osds[0]));
+	dest->size = src->size;
+	dest->primary = src->primary;
+}
+
+static bool is_split(const struct ceph_pg *pgid,
+		     u32 old_pg_num,
+		     u32 new_pg_num)
+{
+	int old_bits = calc_bits_of(old_pg_num);
+	int old_mask = (1 << old_bits) - 1;
+	int n;
+
+	WARN_ON(pgid->seed >= old_pg_num);
+	if (new_pg_num <= old_pg_num)
+		return false;
+
+	for (n = 1; ; n++) {
+		int next_bit = n << (old_bits - 1);
+		u32 s = next_bit | pgid->seed;
+
+		if (s < old_pg_num || s == pgid->seed)
+			continue;
+		if (s >= new_pg_num)
+			break;
+
+		s = ceph_stable_mod(s, old_pg_num, old_mask);
+		if (s == pgid->seed)
+			return true;
+	}
+
+	return false;
+}
+
+bool ceph_is_new_interval(const struct ceph_osds *old_acting,
+			  const struct ceph_osds *new_acting,
+			  const struct ceph_osds *old_up,
+			  const struct ceph_osds *new_up,
+			  int old_size,
+			  int new_size,
+			  int old_min_size,
+			  int new_min_size,
+			  u32 old_pg_num,
+			  u32 new_pg_num,
+			  bool old_sort_bitwise,
+			  bool new_sort_bitwise,
+			  const struct ceph_pg *pgid)
+{
+	return !osds_equal(old_acting, new_acting) ||
+	       !osds_equal(old_up, new_up) ||
+	       old_size != new_size ||
+	       old_min_size != new_min_size ||
+	       is_split(pgid, old_pg_num, new_pg_num) ||
+	       old_sort_bitwise != new_sort_bitwise;
+}
+
+static int calc_pg_rank(int osd, const struct ceph_osds *acting)
+{
+	int i;
+
+	for (i = 0; i < acting->size; i++) {
+		if (acting->osds[i] == osd)
+			return i;
+	}
+
+	return -1;
+}
+
+static bool primary_changed(const struct ceph_osds *old_acting,
+			    const struct ceph_osds *new_acting)
+{
+	if (!old_acting->size && !new_acting->size)
+		return false; /* both still empty */
+
+	if (!old_acting->size ^ !new_acting->size)
+		return true; /* was empty, now not, or vice versa */
+
+	if (old_acting->primary != new_acting->primary)
+		return true; /* primary changed */
+
+	if (calc_pg_rank(old_acting->primary, old_acting) !=
+	    calc_pg_rank(new_acting->primary, new_acting))
+		return true;
+
+	return false; /* same primary (tho replicas may have changed) */
+}
+
+bool ceph_osds_changed(const struct ceph_osds *old_acting,
+		       const struct ceph_osds *new_acting,
+		       bool any_change)
+{
+	if (primary_changed(old_acting, new_acting))
+		return true;
+
+	if (any_change && !__osds_equal(old_acting, new_acting))
+		return true;
+
+	return false;
+}
 
 /*
  * calculate file layout from given offset, length.
@@ -1455,30 +1828,71 @@ invalid:
 EXPORT_SYMBOL(ceph_calc_file_object_mapping);
 
 /*
- * Calculate mapping of a (oloc, oid) pair to a PG.  Should only be
- * called with target's (oloc, oid), since tiering isn't taken into
- * account.
+ * Map an object into a PG.
+ *
+ * Should only be called with target_oid and target_oloc (as opposed to
+ * base_oid and base_oloc), since tiering isn't taken into account.
  */
-int ceph_oloc_oid_to_pg(struct ceph_osdmap *osdmap,
-			struct ceph_object_locator *oloc,
-			struct ceph_object_id *oid,
-			struct ceph_pg *pg_out)
+int ceph_object_locator_to_pg(struct ceph_osdmap *osdmap,
+			      struct ceph_object_id *oid,
+			      struct ceph_object_locator *oloc,
+			      struct ceph_pg *raw_pgid)
 {
 	struct ceph_pg_pool_info *pi;
 
-	pi = __lookup_pg_pool(&osdmap->pg_pools, oloc->pool);
+	pi = ceph_pg_pool_by_id(osdmap, oloc->pool);
 	if (!pi)
-		return -EIO;
+		return -ENOENT;
 
-	pg_out->pool = oloc->pool;
-	pg_out->seed = ceph_str_hash(pi->object_hash, oid->name,
-				     oid->name_len);
+	raw_pgid->pool = oloc->pool;
+	raw_pgid->seed = ceph_str_hash(pi->object_hash, oid->name,
+				       oid->name_len);
 
-	dout("%s '%.*s' pgid %llu.%x\n", __func__, oid->name_len, oid->name,
-	     pg_out->pool, pg_out->seed);
+	dout("%s %s -> raw_pgid %llu.%x\n", __func__, oid->name,
+	     raw_pgid->pool, raw_pgid->seed);
 	return 0;
 }
-EXPORT_SYMBOL(ceph_oloc_oid_to_pg);
+EXPORT_SYMBOL(ceph_object_locator_to_pg);
+
+/*
+ * Map a raw PG (full precision ps) into an actual PG.
+ */
+static void raw_pg_to_pg(struct ceph_pg_pool_info *pi,
+			 const struct ceph_pg *raw_pgid,
+			 struct ceph_pg *pgid)
+{
+	pgid->pool = raw_pgid->pool;
+	pgid->seed = ceph_stable_mod(raw_pgid->seed, pi->pg_num,
+				     pi->pg_num_mask);
+}
+
+/*
+ * Map a raw PG (full precision ps) into a placement ps (placement
+ * seed).  Include pool id in that value so that different pools don't
+ * use the same seeds.
+ */
+static u32 raw_pg_to_pps(struct ceph_pg_pool_info *pi,
+			 const struct ceph_pg *raw_pgid)
+{
+	if (pi->flags & CEPH_POOL_FLAG_HASHPSPOOL) {
+		/* hash pool id and seed so that pool PGs do not overlap */
+		return crush_hash32_2(CRUSH_HASH_RJENKINS1,
+				      ceph_stable_mod(raw_pgid->seed,
+						      pi->pgp_num,
+						      pi->pgp_num_mask),
+				      raw_pgid->pool);
+	} else {
+		/*
+		 * legacy behavior: add ps and pool together.  this is
+		 * not a great approach because the PGs from each pool
+		 * will overlap on top of each other: 0.5 == 1.4 ==
+		 * 2.3 == ...
+		 */
+		return ceph_stable_mod(raw_pgid->seed, pi->pgp_num,
+				       pi->pgp_num_mask) +
+		       (unsigned)raw_pgid->pool;
+	}
+}
 
 static int do_crush(struct ceph_osdmap *map, int ruleno, int x,
 		    int *result, int result_max,
@@ -1497,84 +1911,92 @@ static int do_crush(struct ceph_osdmap *map, int ruleno, int x,
 }
 
 /*
- * Calculate raw (crush) set for given pgid.
+ * Calculate raw set (CRUSH output) for given PG.  The result may
+ * contain nonexistent OSDs.  ->primary is undefined for a raw set.
  *
- * Return raw set length, or error.
+ * Placement seed (CRUSH input) is returned through @ppps.
  */
-static int pg_to_raw_osds(struct ceph_osdmap *osdmap,
-			  struct ceph_pg_pool_info *pool,
-			  struct ceph_pg pgid, u32 pps, int *osds)
+static void pg_to_raw_osds(struct ceph_osdmap *osdmap,
+			   struct ceph_pg_pool_info *pi,
+			   const struct ceph_pg *raw_pgid,
+			   struct ceph_osds *raw,
+			   u32 *ppps)
 {
+	u32 pps = raw_pg_to_pps(pi, raw_pgid);
 	int ruleno;
 	int len;
 
-	/* crush */
-	ruleno = crush_find_rule(osdmap->crush, pool->crush_ruleset,
-				 pool->type, pool->size);
+	ceph_osds_init(raw);
+	if (ppps)
+		*ppps = pps;
+
+	ruleno = crush_find_rule(osdmap->crush, pi->crush_ruleset, pi->type,
+				 pi->size);
 	if (ruleno < 0) {
 		pr_err("no crush rule: pool %lld ruleset %d type %d size %d\n",
-		       pgid.pool, pool->crush_ruleset, pool->type,
-		       pool->size);
-		return -ENOENT;
+		       pi->id, pi->crush_ruleset, pi->type, pi->size);
+		return;
 	}
 
-	len = do_crush(osdmap, ruleno, pps, osds,
-		       min_t(int, pool->size, CEPH_PG_MAX_SIZE),
+	len = do_crush(osdmap, ruleno, pps, raw->osds,
+		       min_t(int, pi->size, ARRAY_SIZE(raw->osds)),
 		       osdmap->osd_weight, osdmap->max_osd);
 	if (len < 0) {
 		pr_err("error %d from crush rule %d: pool %lld ruleset %d type %d size %d\n",
-		       len, ruleno, pgid.pool, pool->crush_ruleset,
-		       pool->type, pool->size);
-		return len;
+		       len, ruleno, pi->id, pi->crush_ruleset, pi->type,
+		       pi->size);
+		return;
 	}
 
-	return len;
+	raw->size = len;
 }
 
 /*
- * Given raw set, calculate up set and up primary.
+ * Given raw set, calculate up set and up primary.  By definition of an
+ * up set, the result won't contain nonexistent or down OSDs.
  *
- * Return up set length.  *primary is set to up primary osd id, or -1
- * if up set is empty.
+ * This is done in-place - on return @set is the up set.  If it's
+ * empty, ->primary will remain undefined.
  */
-static int raw_to_up_osds(struct ceph_osdmap *osdmap,
-			  struct ceph_pg_pool_info *pool,
-			  int *osds, int len, int *primary)
+static void raw_to_up_osds(struct ceph_osdmap *osdmap,
+			   struct ceph_pg_pool_info *pi,
+			   struct ceph_osds *set)
 {
-	int up_primary = -1;
 	int i;
 
-	if (ceph_can_shift_osds(pool)) {
+	/* ->primary is undefined for a raw set */
+	BUG_ON(set->primary != -1);
+
+	if (ceph_can_shift_osds(pi)) {
 		int removed = 0;
 
-		for (i = 0; i < len; i++) {
-			if (ceph_osd_is_down(osdmap, osds[i])) {
+		/* shift left */
+		for (i = 0; i < set->size; i++) {
+			if (ceph_osd_is_down(osdmap, set->osds[i])) {
 				removed++;
 				continue;
 			}
 			if (removed)
-				osds[i - removed] = osds[i];
+				set->osds[i - removed] = set->osds[i];
 		}
-
-		len -= removed;
-		if (len > 0)
-			up_primary = osds[0];
+		set->size -= removed;
+		if (set->size > 0)
+			set->primary = set->osds[0];
 	} else {
-		for (i = len - 1; i >= 0; i--) {
-			if (ceph_osd_is_down(osdmap, osds[i]))
-				osds[i] = CRUSH_ITEM_NONE;
+		/* set down/dne devices to NONE */
+		for (i = set->size - 1; i >= 0; i--) {
+			if (ceph_osd_is_down(osdmap, set->osds[i]))
+				set->osds[i] = CRUSH_ITEM_NONE;
 			else
-				up_primary = osds[i];
+				set->primary = set->osds[i];
 		}
 	}
-
-	*primary = up_primary;
-	return len;
 }
 
-static void apply_primary_affinity(struct ceph_osdmap *osdmap, u32 pps,
-				   struct ceph_pg_pool_info *pool,
-				   int *osds, int len, int *primary)
+static void apply_primary_affinity(struct ceph_osdmap *osdmap,
+				   struct ceph_pg_pool_info *pi,
+				   u32 pps,
+				   struct ceph_osds *up)
 {
 	int i;
 	int pos = -1;
@@ -1586,8 +2008,8 @@ static void apply_primary_affinity(struct ceph_osdmap *osdmap, u32 pps,
 	if (!osdmap->osd_primary_affinity)
 		return;
 
-	for (i = 0; i < len; i++) {
-		int osd = osds[i];
+	for (i = 0; i < up->size; i++) {
+		int osd = up->osds[i];
 
 		if (osd != CRUSH_ITEM_NONE &&
 		    osdmap->osd_primary_affinity[osd] !=
@@ -1595,7 +2017,7 @@ static void apply_primary_affinity(struct ceph_osdmap *osdmap, u32 pps,
 			break;
 		}
 	}
-	if (i == len)
+	if (i == up->size)
 		return;
 
 	/*
@@ -1603,8 +2025,8 @@ static void apply_primary_affinity(struct ceph_osdmap *osdmap, u32 pps,
 	 * osd into the hash/rng so that a proportional fraction of an
 	 * osd's pgs get rejected as primary.
 	 */
-	for (i = 0; i < len; i++) {
-		int osd = osds[i];
+	for (i = 0; i < up->size; i++) {
+		int osd = up->osds[i];
 		u32 aff;
 
 		if (osd == CRUSH_ITEM_NONE)
@@ -1629,135 +2051,110 @@ static void apply_primary_affinity(struct ceph_osdmap *osdmap, u32 pps,
 	if (pos < 0)
 		return;
 
-	*primary = osds[pos];
+	up->primary = up->osds[pos];
 
-	if (ceph_can_shift_osds(pool) && pos > 0) {
+	if (ceph_can_shift_osds(pi) && pos > 0) {
 		/* move the new primary to the front */
 		for (i = pos; i > 0; i--)
-			osds[i] = osds[i - 1];
-		osds[0] = *primary;
+			up->osds[i] = up->osds[i - 1];
+		up->osds[0] = up->primary;
 	}
 }
 
 /*
- * Given up set, apply pg_temp and primary_temp mappings.
+ * Get pg_temp and primary_temp mappings for given PG.
  *
- * Return acting set length.  *primary is set to acting primary osd id,
- * or -1 if acting set is empty.
+ * Note that a PG may have none, only pg_temp, only primary_temp or
+ * both pg_temp and primary_temp mappings.  This means @temp isn't
+ * always a valid OSD set on return: in the "only primary_temp" case,
+ * @temp will have its ->primary >= 0 but ->size == 0.
  */
-static int apply_temps(struct ceph_osdmap *osdmap,
-		       struct ceph_pg_pool_info *pool, struct ceph_pg pgid,
-		       int *osds, int len, int *primary)
+static void get_temp_osds(struct ceph_osdmap *osdmap,
+			  struct ceph_pg_pool_info *pi,
+			  const struct ceph_pg *raw_pgid,
+			  struct ceph_osds *temp)
 {
+	struct ceph_pg pgid;
 	struct ceph_pg_mapping *pg;
-	int temp_len;
-	int temp_primary;
 	int i;
 
-	/* raw_pg -> pg */
-	pgid.seed = ceph_stable_mod(pgid.seed, pool->pg_num,
-				    pool->pg_num_mask);
+	raw_pg_to_pg(pi, raw_pgid, &pgid);
+	ceph_osds_init(temp);
 
 	/* pg_temp? */
 	pg = __lookup_pg_mapping(&osdmap->pg_temp, pgid);
 	if (pg) {
-		temp_len = 0;
-		temp_primary = -1;
-
 		for (i = 0; i < pg->pg_temp.len; i++) {
 			if (ceph_osd_is_down(osdmap, pg->pg_temp.osds[i])) {
-				if (ceph_can_shift_osds(pool))
+				if (ceph_can_shift_osds(pi))
 					continue;
-				else
-					osds[temp_len++] = CRUSH_ITEM_NONE;
+
+				temp->osds[temp->size++] = CRUSH_ITEM_NONE;
 			} else {
-				osds[temp_len++] = pg->pg_temp.osds[i];
+				temp->osds[temp->size++] = pg->pg_temp.osds[i];
 			}
 		}
 
 		/* apply pg_temp's primary */
-		for (i = 0; i < temp_len; i++) {
-			if (osds[i] != CRUSH_ITEM_NONE) {
-				temp_primary = osds[i];
+		for (i = 0; i < temp->size; i++) {
+			if (temp->osds[i] != CRUSH_ITEM_NONE) {
+				temp->primary = temp->osds[i];
 				break;
 			}
 		}
-	} else {
-		temp_len = len;
-		temp_primary = *primary;
 	}
 
 	/* primary_temp? */
 	pg = __lookup_pg_mapping(&osdmap->primary_temp, pgid);
 	if (pg)
-		temp_primary = pg->primary_temp.osd;
-
-	*primary = temp_primary;
-	return temp_len;
+		temp->primary = pg->primary_temp.osd;
 }
 
 /*
- * Calculate acting set for given pgid.
+ * Map a PG to its acting set as well as its up set.
  *
- * Return acting set length, or error.  *primary is set to acting
- * primary osd id, or -1 if acting set is empty or on error.
+ * Acting set is used for data mapping purposes, while up set can be
+ * recorded for detecting interval changes and deciding whether to
+ * resend a request.
  */
-int ceph_calc_pg_acting(struct ceph_osdmap *osdmap, struct ceph_pg pgid,
-			int *osds, int *primary)
+void ceph_pg_to_up_acting_osds(struct ceph_osdmap *osdmap,
+			       const struct ceph_pg *raw_pgid,
+			       struct ceph_osds *up,
+			       struct ceph_osds *acting)
 {
-	struct ceph_pg_pool_info *pool;
+	struct ceph_pg_pool_info *pi;
 	u32 pps;
-	int len;
 
-	pool = __lookup_pg_pool(&osdmap->pg_pools, pgid.pool);
-	if (!pool) {
-		*primary = -1;
-		return -ENOENT;
+	pi = ceph_pg_pool_by_id(osdmap, raw_pgid->pool);
+	if (!pi) {
+		ceph_osds_init(up);
+		ceph_osds_init(acting);
+		goto out;
 	}
 
-	if (pool->flags & CEPH_POOL_FLAG_HASHPSPOOL) {
-		/* hash pool id and seed so that pool PGs do not overlap */
-		pps = crush_hash32_2(CRUSH_HASH_RJENKINS1,
-				     ceph_stable_mod(pgid.seed, pool->pgp_num,
-						     pool->pgp_num_mask),
-				     pgid.pool);
-	} else {
-		/*
-		 * legacy behavior: add ps and pool together.  this is
-		 * not a great approach because the PGs from each pool
-		 * will overlap on top of each other: 0.5 == 1.4 ==
-		 * 2.3 == ...
-		 */
-		pps = ceph_stable_mod(pgid.seed, pool->pgp_num,
-				      pool->pgp_num_mask) +
-			(unsigned)pgid.pool;
+	pg_to_raw_osds(osdmap, pi, raw_pgid, up, &pps);
+	raw_to_up_osds(osdmap, pi, up);
+	apply_primary_affinity(osdmap, pi, pps, up);
+	get_temp_osds(osdmap, pi, raw_pgid, acting);
+	if (!acting->size) {
+		memcpy(acting->osds, up->osds, up->size * sizeof(up->osds[0]));
+		acting->size = up->size;
+		if (acting->primary == -1)
+			acting->primary = up->primary;
 	}
-
-	len = pg_to_raw_osds(osdmap, pool, pgid, pps, osds);
-	if (len < 0) {
-		*primary = -1;
-		return len;
-	}
-
-	len = raw_to_up_osds(osdmap, pool, osds, len, primary);
-
-	apply_primary_affinity(osdmap, pps, pool, osds, len, primary);
-
-	len = apply_temps(osdmap, pool, pgid, osds, len, primary);
-
-	return len;
+out:
+	WARN_ON(!osds_valid(up) || !osds_valid(acting));
 }
 
 /*
- * Return primary osd for given pgid, or -1 if none.
+ * Return acting primary for given PG, or -1 if none.
  */
-int ceph_calc_pg_primary(struct ceph_osdmap *osdmap, struct ceph_pg pgid)
+int ceph_pg_to_acting_primary(struct ceph_osdmap *osdmap,
+			      const struct ceph_pg *raw_pgid)
 {
-	int osds[CEPH_PG_MAX_SIZE];
-	int primary;
-
-	ceph_calc_pg_acting(osdmap, pgid, osds, &primary);
+	struct ceph_osds up, acting;
 
-	return primary;
+	ceph_pg_to_up_acting_osds(osdmap, raw_pgid, &up, &acting);
+	return acting.primary;
 }
-EXPORT_SYMBOL(ceph_calc_pg_primary);
+EXPORT_SYMBOL(ceph_pg_to_acting_primary);