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

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (59 commits)
  ceph: reuse mon subscribe message instead of allocated anew
  ceph: avoid resending queued message to monitor
  ceph: Storage class should be before const qualifier
  ceph: all allocation functions should get gfp_mask
  ceph: specify max_bytes on readdir replies
  ceph: cleanup pool op strings
  ceph: Use kzalloc
  ceph: use common helper for aborted dir request invalidation
  ceph: cope with out of order (unsafe after safe) mds reply
  ceph: save peer feature bits in connection structure
  ceph: resync headers with userland
  ceph: use ceph. prefix for virtual xattrs
  ceph: throw out dirty caps metadata, data on session teardown
  ceph: attempt mds reconnect if mds closes our session
  ceph: clean up send_mds_reconnect interface
  ceph: wait for mds OPEN reply to indicate reconnect success
  ceph: only send cap releases when mds is OPEN|HUNG
  ceph: dicard cap releases on mds restart
  ceph: make mon client statfs handling more generic
  ceph: drop src address(es) from message header [new protocol feature]
  ...

1 files changed, 237 insertions, 148 deletions

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 24561a557e0..885aa5710cf 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -40,7 +40,7 @@
 static void __wake_requests(struct ceph_mds_client *mdsc,
 			    struct list_head *head);
 
-const static struct ceph_connection_operations mds_con_ops;
+static const struct ceph_connection_operations mds_con_ops;
 
 
 /*
@@ -665,10 +665,10 @@ static struct ceph_msg *create_session_msg(u32 op, u64 seq)
 	struct ceph_msg *msg;
 	struct ceph_mds_session_head *h;
 
-	msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), 0, 0, NULL);
-	if (IS_ERR(msg)) {
+	msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), GFP_NOFS);
+	if (!msg) {
 		pr_err("create_session_msg ENOMEM creating msg\n");
-		return ERR_PTR(PTR_ERR(msg));
+		return NULL;
 	}
 	h = msg->front.iov_base;
 	h->op = cpu_to_le32(op);
@@ -687,7 +687,6 @@ static int __open_session(struct ceph_mds_client *mdsc,
 	struct ceph_msg *msg;
 	int mstate;
 	int mds = session->s_mds;
-	int err = 0;
 
 	/* wait for mds to go active? */
 	mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
@@ -698,13 +697,9 @@ static int __open_session(struct ceph_mds_client *mdsc,
 
 	/* send connect message */
 	msg = create_session_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq);
-	if (IS_ERR(msg)) {
-		err = PTR_ERR(msg);
-		goto out;
-	}
+	if (!msg)
+		return -ENOMEM;
 	ceph_con_send(&session->s_con, msg);
-
-out:
 	return 0;
 }
 
@@ -804,12 +799,49 @@ out:
 }
 
 static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
-				   void *arg)
+				  void *arg)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
+	int drop = 0;
+
 	dout("removing cap %p, ci is %p, inode is %p\n",
 	     cap, ci, &ci->vfs_inode);
-	ceph_remove_cap(cap);
+	spin_lock(&inode->i_lock);
+	__ceph_remove_cap(cap);
+	if (!__ceph_is_any_real_caps(ci)) {
+		struct ceph_mds_client *mdsc =
+			&ceph_sb_to_client(inode->i_sb)->mdsc;
+
+		spin_lock(&mdsc->cap_dirty_lock);
+		if (!list_empty(&ci->i_dirty_item)) {
+			pr_info(" dropping dirty %s state for %p %lld\n",
+				ceph_cap_string(ci->i_dirty_caps),
+				inode, ceph_ino(inode));
+			ci->i_dirty_caps = 0;
+			list_del_init(&ci->i_dirty_item);
+			drop = 1;
+		}
+		if (!list_empty(&ci->i_flushing_item)) {
+			pr_info(" dropping dirty+flushing %s state for %p %lld\n",
+				ceph_cap_string(ci->i_flushing_caps),
+				inode, ceph_ino(inode));
+			ci->i_flushing_caps = 0;
+			list_del_init(&ci->i_flushing_item);
+			mdsc->num_cap_flushing--;
+			drop = 1;
+		}
+		if (drop && ci->i_wrbuffer_ref) {
+			pr_info(" dropping dirty data for %p %lld\n",
+				inode, ceph_ino(inode));
+			ci->i_wrbuffer_ref = 0;
+			ci->i_wrbuffer_ref_head = 0;
+			drop++;
+		}
+		spin_unlock(&mdsc->cap_dirty_lock);
+	}
+	spin_unlock(&inode->i_lock);
+	while (drop--)
+		iput(inode);
 	return 0;
 }
 
@@ -821,6 +853,7 @@ static void remove_session_caps(struct ceph_mds_session *session)
 	dout("remove_session_caps on %p\n", session);
 	iterate_session_caps(session, remove_session_caps_cb, NULL);
 	BUG_ON(session->s_nr_caps > 0);
+	BUG_ON(!list_empty(&session->s_cap_flushing));
 	cleanup_cap_releases(session);
 }
 
@@ -883,8 +916,8 @@ static int send_renew_caps(struct ceph_mds_client *mdsc,
 		ceph_mds_state_name(state));
 	msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
 				 ++session->s_renew_seq);
-	if (IS_ERR(msg))
-		return PTR_ERR(msg);
+	if (!msg)
+		return -ENOMEM;
 	ceph_con_send(&session->s_con, msg);
 	return 0;
 }
@@ -931,17 +964,15 @@ static int request_close_session(struct ceph_mds_client *mdsc,
 				 struct ceph_mds_session *session)
 {
 	struct ceph_msg *msg;
-	int err = 0;
 
 	dout("request_close_session mds%d state %s seq %lld\n",
 	     session->s_mds, session_state_name(session->s_state),
 	     session->s_seq);
 	msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
-	if (IS_ERR(msg))
-		err = PTR_ERR(msg);
-	else
-		ceph_con_send(&session->s_con, msg);
-	return err;
+	if (!msg)
+		return -ENOMEM;
+	ceph_con_send(&session->s_con, msg);
+	return 0;
 }
 
 /*
@@ -1059,7 +1090,7 @@ static int add_cap_releases(struct ceph_mds_client *mdsc,
 	while (session->s_num_cap_releases < session->s_nr_caps + extra) {
 		spin_unlock(&session->s_cap_lock);
 		msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE,
-				   0, 0, NULL);
+				   GFP_NOFS);
 		if (!msg)
 			goto out_unlocked;
 		dout("add_cap_releases %p msg %p now %d\n", session, msg,
@@ -1151,10 +1182,8 @@ static void send_cap_releases(struct ceph_mds_client *mdsc,
 	struct ceph_msg *msg;
 
 	dout("send_cap_releases mds%d\n", session->s_mds);
-	while (1) {
-		spin_lock(&session->s_cap_lock);
-		if (list_empty(&session->s_cap_releases_done))
-			break;
+	spin_lock(&session->s_cap_lock);
+	while (!list_empty(&session->s_cap_releases_done)) {
 		msg = list_first_entry(&session->s_cap_releases_done,
 				 struct ceph_msg, list_head);
 		list_del_init(&msg->list_head);
@@ -1162,10 +1191,49 @@ static void send_cap_releases(struct ceph_mds_client *mdsc,
 		msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
 		dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
 		ceph_con_send(&session->s_con, msg);
+		spin_lock(&session->s_cap_lock);
 	}
 	spin_unlock(&session->s_cap_lock);
 }
 
+static void discard_cap_releases(struct ceph_mds_client *mdsc,
+				 struct ceph_mds_session *session)
+{
+	struct ceph_msg *msg;
+	struct ceph_mds_cap_release *head;
+	unsigned num;
+
+	dout("discard_cap_releases mds%d\n", session->s_mds);
+	spin_lock(&session->s_cap_lock);
+
+	/* zero out the in-progress message */
+	msg = list_first_entry(&session->s_cap_releases,
+			       struct ceph_msg, list_head);
+	head = msg->front.iov_base;
+	num = le32_to_cpu(head->num);
+	dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg, num);
+	head->num = cpu_to_le32(0);
+	session->s_num_cap_releases += num;
+
+	/* requeue completed messages */
+	while (!list_empty(&session->s_cap_releases_done)) {
+		msg = list_first_entry(&session->s_cap_releases_done,
+				 struct ceph_msg, list_head);
+		list_del_init(&msg->list_head);
+
+		head = msg->front.iov_base;
+		num = le32_to_cpu(head->num);
+		dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg,
+		     num);
+		session->s_num_cap_releases += num;
+		head->num = cpu_to_le32(0);
+		msg->front.iov_len = sizeof(*head);
+		list_add(&msg->list_head, &session->s_cap_releases);
+	}
+
+	spin_unlock(&session->s_cap_lock);
+}
+
 /*
  * requests
  */
@@ -1181,6 +1249,7 @@ ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
 	if (!req)
 		return ERR_PTR(-ENOMEM);
 
+	mutex_init(&req->r_fill_mutex);
 	req->r_started = jiffies;
 	req->r_resend_mds = -1;
 	INIT_LIST_HEAD(&req->r_unsafe_dir_item);
@@ -1251,7 +1320,7 @@ retry:
 			len += 1 + temp->d_name.len;
 		temp = temp->d_parent;
 		if (temp == NULL) {
-			pr_err("build_path_dentry corrupt dentry %p\n", dentry);
+			pr_err("build_path corrupt dentry %p\n", dentry);
 			return ERR_PTR(-EINVAL);
 		}
 	}
@@ -1267,7 +1336,7 @@ retry:
 		struct inode *inode = temp->d_inode;
 
 		if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
-			dout("build_path_dentry path+%d: %p SNAPDIR\n",
+			dout("build_path path+%d: %p SNAPDIR\n",
 			     pos, temp);
 		} else if (stop_on_nosnap && inode &&
 			   ceph_snap(inode) == CEPH_NOSNAP) {
@@ -1278,20 +1347,18 @@ retry:
 				break;
 			strncpy(path + pos, temp->d_name.name,
 				temp->d_name.len);
-			dout("build_path_dentry path+%d: %p '%.*s'\n",
-			     pos, temp, temp->d_name.len, path + pos);
 		}
 		if (pos)
 			path[--pos] = '/';
 		temp = temp->d_parent;
 		if (temp == NULL) {
-			pr_err("build_path_dentry corrupt dentry\n");
+			pr_err("build_path corrupt dentry\n");
 			kfree(path);
 			return ERR_PTR(-EINVAL);
 		}
 	}
 	if (pos != 0) {
-		pr_err("build_path_dentry did not end path lookup where "
+		pr_err("build_path did not end path lookup where "
 		       "expected, namelen is %d, pos is %d\n", len, pos);
 		/* presumably this is only possible if racing with a
 		   rename of one of the parent directories (we can not
@@ -1303,7 +1370,7 @@ retry:
 
 	*base = ceph_ino(temp->d_inode);
 	*plen = len;
-	dout("build_path_dentry on %p %d built %llx '%.*s'\n",
+	dout("build_path on %p %d built %llx '%.*s'\n",
 	     dentry, atomic_read(&dentry->d_count), *base, len, path);
 	return path;
 }
@@ -1426,9 +1493,11 @@ static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
 	if (req->r_old_dentry_drop)
 		len += req->r_old_dentry->d_name.len;
 
-	msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, 0, 0, NULL);
-	if (IS_ERR(msg))
+	msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, GFP_NOFS);
+	if (!msg) {
+		msg = ERR_PTR(-ENOMEM);
 		goto out_free2;
+	}
 
 	msg->hdr.tid = cpu_to_le64(req->r_tid);
 
@@ -1517,9 +1586,9 @@ static int __prepare_send_request(struct ceph_mds_client *mdsc,
 	}
 	msg = create_request_message(mdsc, req, mds);
 	if (IS_ERR(msg)) {
-		req->r_reply = ERR_PTR(PTR_ERR(msg));
+		req->r_err = PTR_ERR(msg);
 		complete_request(mdsc, req);
-		return -PTR_ERR(msg);
+		return PTR_ERR(msg);
 	}
 	req->r_request = msg;
 
@@ -1552,7 +1621,7 @@ static int __do_request(struct ceph_mds_client *mdsc,
 	int mds = -1;
 	int err = -EAGAIN;
 
-	if (req->r_reply)
+	if (req->r_err || req->r_got_result)
 		goto out;
 
 	if (req->r_timeout &&
@@ -1609,7 +1678,7 @@ out:
 	return err;
 
 finish:
-	req->r_reply = ERR_PTR(err);
+	req->r_err = err;
 	complete_request(mdsc, req);
 	goto out;
 }
@@ -1630,10 +1699,9 @@ static void __wake_requests(struct ceph_mds_client *mdsc,
 
 /*
  * Wake up threads with requests pending for @mds, so that they can
- * resubmit their requests to a possibly different mds.  If @all is set,
- * wake up if their requests has been forwarded to @mds, too.
+ * resubmit their requests to a possibly different mds.
  */
-static void kick_requests(struct ceph_mds_client *mdsc, int mds, int all)
+static void kick_requests(struct ceph_mds_client *mdsc, int mds)
 {
 	struct ceph_mds_request *req;
 	struct rb_node *p;
@@ -1689,64 +1757,78 @@ int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
 	__register_request(mdsc, req, dir);
 	__do_request(mdsc, req);
 
-	/* wait */
-	if (!req->r_reply) {
-		mutex_unlock(&mdsc->mutex);
-		if (req->r_timeout) {
-			err = (long)wait_for_completion_interruptible_timeout(
-				&req->r_completion, req->r_timeout);
-			if (err == 0)
-				req->r_reply = ERR_PTR(-EIO);
-			else if (err < 0)
-				req->r_reply = ERR_PTR(err);
-		} else {
-                        err = wait_for_completion_interruptible(
-                                &req->r_completion);
-                        if (err)
-                                req->r_reply = ERR_PTR(err);
-		}
-		mutex_lock(&mdsc->mutex);
+	if (req->r_err) {
+		err = req->r_err;
+		__unregister_request(mdsc, req);
+		dout("do_request early error %d\n", err);
+		goto out;
 	}
 
-	if (IS_ERR(req->r_reply)) {
-		err = PTR_ERR(req->r_reply);
-		req->r_reply = NULL;
+	/* wait */
+	mutex_unlock(&mdsc->mutex);
+	dout("do_request waiting\n");
+	if (req->r_timeout) {
+		err = (long)wait_for_completion_interruptible_timeout(
+			&req->r_completion, req->r_timeout);
+		if (err == 0)
+			err = -EIO;
+	} else {
+		err = wait_for_completion_interruptible(&req->r_completion);
+	}
+	dout("do_request waited, got %d\n", err);
+	mutex_lock(&mdsc->mutex);
 
-		if (err == -ERESTARTSYS) {
-			/* aborted */
-			req->r_aborted = true;
+	/* only abort if we didn't race with a real reply */
+	if (req->r_got_result) {
+		err = le32_to_cpu(req->r_reply_info.head->result);
+	} else if (err < 0) {
+		dout("aborted request %lld with %d\n", req->r_tid, err);
 
-			if (req->r_locked_dir &&
-			    (req->r_op & CEPH_MDS_OP_WRITE)) {
-				struct ceph_inode_info *ci =
-					ceph_inode(req->r_locked_dir);
+		/*
+		 * ensure we aren't running concurrently with
+		 * ceph_fill_trace or ceph_readdir_prepopulate, which
+		 * rely on locks (dir mutex) held by our caller.
+		 */
+		mutex_lock(&req->r_fill_mutex);
+		req->r_err = err;
+		req->r_aborted = true;
+		mutex_unlock(&req->r_fill_mutex);
 
-				dout("aborted, clearing I_COMPLETE on %p\n", 
-				     req->r_locked_dir);
-				spin_lock(&req->r_locked_dir->i_lock);
-				ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
-				ci->i_release_count++;
-				spin_unlock(&req->r_locked_dir->i_lock);
-			}
-		} else {
-			/* clean up this request */
-			__unregister_request(mdsc, req);
-			if (!list_empty(&req->r_unsafe_item))
-				list_del_init(&req->r_unsafe_item);
-			complete(&req->r_safe_completion);
-		}
-	} else if (req->r_err) {
-		err = req->r_err;
+		if (req->r_locked_dir &&
+		    (req->r_op & CEPH_MDS_OP_WRITE))
+			ceph_invalidate_dir_request(req);
 	} else {
-		err = le32_to_cpu(req->r_reply_info.head->result);
+		err = req->r_err;
 	}
-	mutex_unlock(&mdsc->mutex);
 
+out:
+	mutex_unlock(&mdsc->mutex);
 	dout("do_request %p done, result %d\n", req, err);
 	return err;
 }
 
 /*
+ * Invalidate dir I_COMPLETE, dentry lease state on an aborted MDS
+ * namespace request.
+ */
+void ceph_invalidate_dir_request(struct ceph_mds_request *req)
+{
+	struct inode *inode = req->r_locked_dir;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+
+	dout("invalidate_dir_request %p (I_COMPLETE, lease(s))\n", inode);
+	spin_lock(&inode->i_lock);
+	ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
+	ci->i_release_count++;
+	spin_unlock(&inode->i_lock);
+
+	if (req->r_dentry)
+		ceph_invalidate_dentry_lease(req->r_dentry);
+	if (req->r_old_dentry)
+		ceph_invalidate_dentry_lease(req->r_old_dentry);
+}
+
+/*
  * Handle mds reply.
  *
  * We take the session mutex and parse and process the reply immediately.
@@ -1797,6 +1879,12 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
 		mutex_unlock(&mdsc->mutex);
 		goto out;
 	}
+	if (req->r_got_safe && !head->safe) {
+		pr_warning("got unsafe after safe on %llu from mds%d\n",
+			   tid, mds);
+		mutex_unlock(&mdsc->mutex);
+		goto out;
+	}
 
 	result = le32_to_cpu(head->result);
 
@@ -1838,11 +1926,7 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
 			mutex_unlock(&mdsc->mutex);
 			goto out;
 		}
-	}
-
-	BUG_ON(req->r_reply);
-
-	if (!head->safe) {
+	} else {
 		req->r_got_unsafe = true;
 		list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
 	}
@@ -1871,21 +1955,30 @@ static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
 	}
 
 	/* insert trace into our cache */
+	mutex_lock(&req->r_fill_mutex);
 	err = ceph_fill_trace(mdsc->client->sb, req, req->r_session);
 	if (err == 0) {
 		if (result == 0 && rinfo->dir_nr)
 			ceph_readdir_prepopulate(req, req->r_session);
 		ceph_unreserve_caps(&req->r_caps_reservation);
 	}
+	mutex_unlock(&req->r_fill_mutex);
 
 	up_read(&mdsc->snap_rwsem);
 out_err:
-	if (err) {
-		req->r_err = err;
+	mutex_lock(&mdsc->mutex);
+	if (!req->r_aborted) {
+		if (err) {
+			req->r_err = err;
+		} else {
+			req->r_reply = msg;
+			ceph_msg_get(msg);
+			req->r_got_result = true;
+		}
 	} else {
-		req->r_reply = msg;
-		ceph_msg_get(msg);
+		dout("reply arrived after request %lld was aborted\n", tid);
 	}
+	mutex_unlock(&mdsc->mutex);
 
 	add_cap_releases(mdsc, req->r_session, -1);
 	mutex_unlock(&session->s_mutex);
@@ -1984,6 +2077,8 @@ static void handle_session(struct ceph_mds_session *session,
 
 	switch (op) {
 	case CEPH_SESSION_OPEN:
+		if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
+			pr_info("mds%d reconnect success\n", session->s_mds);
 		session->s_state = CEPH_MDS_SESSION_OPEN;
 		renewed_caps(mdsc, session, 0);
 		wake = 1;
@@ -1997,10 +2092,12 @@ static void handle_session(struct ceph_mds_session *session,
 		break;
 
 	case CEPH_SESSION_CLOSE:
+		if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
+			pr_info("mds%d reconnect denied\n", session->s_mds);
 		remove_session_caps(session);
 		wake = 1; /* for good measure */
 		complete(&mdsc->session_close_waiters);
-		kick_requests(mdsc, mds, 0);      /* cur only */
+		kick_requests(mdsc, mds);
 		break;
 
 	case CEPH_SESSION_STALE:
@@ -2132,54 +2229,44 @@ out:
  *
  * called with mdsc->mutex held.
  */
-static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
+static void send_mds_reconnect(struct ceph_mds_client *mdsc,
+			       struct ceph_mds_session *session)
 {
-	struct ceph_mds_session *session = NULL;
 	struct ceph_msg *reply;
 	struct rb_node *p;
+	int mds = session->s_mds;
 	int err = -ENOMEM;
 	struct ceph_pagelist *pagelist;
 
-	pr_info("reconnect to recovering mds%d\n", mds);
+	pr_info("mds%d reconnect start\n", mds);
 
 	pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
 	if (!pagelist)
 		goto fail_nopagelist;
 	ceph_pagelist_init(pagelist);
 
-	reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, 0, 0, NULL);
-	if (IS_ERR(reply)) {
-		err = PTR_ERR(reply);
+	reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, GFP_NOFS);
+	if (!reply)
 		goto fail_nomsg;
-	}
-
-	/* find session */
-	session = __ceph_lookup_mds_session(mdsc, mds);
-	mutex_unlock(&mdsc->mutex);    /* drop lock for duration */
 
-	if (session) {
-		mutex_lock(&session->s_mutex);
+	mutex_lock(&session->s_mutex);
+	session->s_state = CEPH_MDS_SESSION_RECONNECTING;
+	session->s_seq = 0;
 
-		session->s_state = CEPH_MDS_SESSION_RECONNECTING;
-		session->s_seq = 0;
+	ceph_con_open(&session->s_con,
+		      ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
 
-		ceph_con_open(&session->s_con,
-			      ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
-
-		/* replay unsafe requests */
-		replay_unsafe_requests(mdsc, session);
-	} else {
-		dout("no session for mds%d, will send short reconnect\n",
-		     mds);
-	}
+	/* replay unsafe requests */
+	replay_unsafe_requests(mdsc, session);
 
 	down_read(&mdsc->snap_rwsem);
 
-	if (!session)
-		goto send;
 	dout("session %p state %s\n", session,
 	     session_state_name(session->s_state));
 
+	/* drop old cap expires; we're about to reestablish that state */
+	discard_cap_releases(mdsc, session);
+
 	/* traverse this session's caps */
 	err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);
 	if (err)
@@ -2208,36 +2295,29 @@ static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
 			goto fail;
 	}
 
-send:
 	reply->pagelist = pagelist;
 	reply->hdr.data_len = cpu_to_le32(pagelist->length);
 	reply->nr_pages = calc_pages_for(0, pagelist->length);
 	ceph_con_send(&session->s_con, reply);
 
-	session->s_state = CEPH_MDS_SESSION_OPEN;
 	mutex_unlock(&session->s_mutex);
 
 	mutex_lock(&mdsc->mutex);
 	__wake_requests(mdsc, &session->s_waiting);
 	mutex_unlock(&mdsc->mutex);
 
-	ceph_put_mds_session(session);
-
 	up_read(&mdsc->snap_rwsem);
-	mutex_lock(&mdsc->mutex);
 	return;
 
 fail:
 	ceph_msg_put(reply);
 	up_read(&mdsc->snap_rwsem);
 	mutex_unlock(&session->s_mutex);
-	ceph_put_mds_session(session);
 fail_nomsg:
 	ceph_pagelist_release(pagelist);
 	kfree(pagelist);
 fail_nopagelist:
 	pr_err("error %d preparing reconnect for mds%d\n", err, mds);
-	mutex_lock(&mdsc->mutex);
 	return;
 }
 
@@ -2290,7 +2370,7 @@ static void check_new_map(struct ceph_mds_client *mdsc,
 			}
 
 			/* kick any requests waiting on the recovering mds */
-			kick_requests(mdsc, i, 1);
+			kick_requests(mdsc, i);
 		} else if (oldstate == newstate) {
 			continue;  /* nothing new with this mds */
 		}
@@ -2299,22 +2379,21 @@ static void check_new_map(struct ceph_mds_client *mdsc,
 		 * send reconnect?
 		 */
 		if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
-		    newstate >= CEPH_MDS_STATE_RECONNECT)
-			send_mds_reconnect(mdsc, i);
+		    newstate >= CEPH_MDS_STATE_RECONNECT) {
+			mutex_unlock(&mdsc->mutex);
+			send_mds_reconnect(mdsc, s);
+			mutex_lock(&mdsc->mutex);
+		}
 
 		/*
-		 * kick requests on any mds that has gone active.
-		 *
-		 * kick requests on cur or forwarder: we may have sent
-		 * the request to mds1, mds1 told us it forwarded it
-		 * to mds2, but then we learn mds1 failed and can't be
-		 * sure it successfully forwarded our request before
-		 * it died.
+		 * kick request on any mds that has gone active.
 		 */
 		if (oldstate < CEPH_MDS_STATE_ACTIVE &&
 		    newstate >= CEPH_MDS_STATE_ACTIVE) {
-			pr_info("mds%d reconnect completed\n", s->s_mds);
-			kick_requests(mdsc, i, 1);
+			if (oldstate != CEPH_MDS_STATE_CREATING &&
+			    oldstate != CEPH_MDS_STATE_STARTING)
+				pr_info("mds%d recovery completed\n", s->s_mds);
+			kick_requests(mdsc, i);
 			ceph_kick_flushing_caps(mdsc, s);
 			wake_up_session_caps(s, 1);
 		}
@@ -2457,8 +2536,8 @@ void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
 	dnamelen = dentry->d_name.len;
 	len += dnamelen;
 
-	msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, 0, 0, NULL);
-	if (IS_ERR(msg))
+	msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS);
+	if (!msg)
 		return;
 	lease = msg->front.iov_base;
 	lease->action = action;
@@ -2603,7 +2682,9 @@ static void delayed_work(struct work_struct *work)
 		else
 			ceph_con_keepalive(&s->s_con);
 		add_cap_releases(mdsc, s, -1);
-		send_cap_releases(mdsc, s);
+		if (s->s_state == CEPH_MDS_SESSION_OPEN ||
+		    s->s_state == CEPH_MDS_SESSION_HUNG)
+			send_cap_releases(mdsc, s);
 		mutex_unlock(&s->s_mutex);
 		ceph_put_mds_session(s);
 
@@ -2620,6 +2701,9 @@ int ceph_mdsc_init(struct ceph_mds_client *mdsc, struct ceph_client *client)
 	mdsc->client = client;
 	mutex_init(&mdsc->mutex);
 	mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
+	if (mdsc->mdsmap == NULL)
+		return -ENOMEM;
+
 	init_completion(&mdsc->safe_umount_waiters);
 	init_completion(&mdsc->session_close_waiters);
 	INIT_LIST_HEAD(&mdsc->waiting_for_map);
@@ -2645,6 +2729,7 @@ int ceph_mdsc_init(struct ceph_mds_client *mdsc, struct ceph_client *client)
 	init_waitqueue_head(&mdsc->cap_flushing_wq);
 	spin_lock_init(&mdsc->dentry_lru_lock);
 	INIT_LIST_HEAD(&mdsc->dentry_lru);
+
 	return 0;
 }
 
@@ -2740,6 +2825,9 @@ void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
 {
 	u64 want_tid, want_flush;
 
+	if (mdsc->client->mount_state == CEPH_MOUNT_SHUTDOWN)
+		return;
+
 	dout("sync\n");
 	mutex_lock(&mdsc->mutex);
 	want_tid = mdsc->last_tid;
@@ -2922,9 +3010,10 @@ static void con_put(struct ceph_connection *con)
 static void peer_reset(struct ceph_connection *con)
 {
 	struct ceph_mds_session *s = con->private;
+	struct ceph_mds_client *mdsc = s->s_mdsc;
 
-	pr_err("mds%d gave us the boot.  IMPLEMENT RECONNECT.\n",
-	       s->s_mds);
+	pr_warning("mds%d closed our session\n", s->s_mds);
+	send_mds_reconnect(mdsc, s);
 }
 
 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
@@ -3031,7 +3120,7 @@ static int invalidate_authorizer(struct ceph_connection *con)
 	return ceph_monc_validate_auth(&mdsc->client->monc);
 }
 
-const static struct ceph_connection_operations mds_con_ops = {
+static const struct ceph_connection_operations mds_con_ops = {
 	.get = con_get,
 	.put = con_put,
 	.dispatch = dispatch,