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: (22 commits)
  ceph: do not carry i_lock for readdir from dcache
  fs/ceph/xattr.c: Use kmemdup
  rbd: passing wrong variable to bvec_kunmap_irq()
  rbd: null vs ERR_PTR
  ceph: fix num_pages_free accounting in pagelist
  ceph: add CEPH_MDS_OP_SETDIRLAYOUT and associated ioctl.
  ceph: don't crash when passed bad mount options
  ceph: fix debugfs warnings
  block: rbd: removing unnecessary test
  block: rbd: fixed may leaks
  ceph: switch from BKL to lock_flocks()
  ceph: preallocate flock state without locks held
  ceph: add pagelist_reserve, pagelist_truncate, pagelist_set_cursor
  ceph: use mapping->nrpages to determine if mapping is empty
  ceph: only invalidate on check_caps if we actually have pages
  ceph: do not hide .snap in root directory
  rbd: introduce rados block device (rbd), based on libceph
  ceph: factor out libceph from Ceph file system
  ceph-rbd: osdc support for osd call and rollback operations
  ceph: messenger and osdc changes for rbd
  ...

1 files changed, 1027 insertions, 0 deletions

diff --git a/net/ceph/mon_client.c b/net/ceph/mon_client.c
new file mode 100644
index 000000000000..8a079399174a
--- /dev/null
+++ b/net/ceph/mon_client.c
@@ -0,0 +1,1027 @@
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/sched.h>
+
+#include <linux/ceph/mon_client.h>
+#include <linux/ceph/libceph.h>
+#include <linux/ceph/decode.h>
+
+#include <linux/ceph/auth.h>
+
+/*
+ * Interact with Ceph monitor cluster.  Handle requests for new map
+ * versions, and periodically resend as needed.  Also implement
+ * statfs() and umount().
+ *
+ * A small cluster of Ceph "monitors" are responsible for managing critical
+ * cluster configuration and state information.  An odd number (e.g., 3, 5)
+ * of cmon daemons use a modified version of the Paxos part-time parliament
+ * algorithm to manage the MDS map (mds cluster membership), OSD map, and
+ * list of clients who have mounted the file system.
+ *
+ * We maintain an open, active session with a monitor at all times in order to
+ * receive timely MDSMap updates.  We periodically send a keepalive byte on the
+ * TCP socket to ensure we detect a failure.  If the connection does break, we
+ * randomly hunt for a new monitor.  Once the connection is reestablished, we
+ * resend any outstanding requests.
+ */
+
+static const struct ceph_connection_operations mon_con_ops;
+
+static int __validate_auth(struct ceph_mon_client *monc);
+
+/*
+ * Decode a monmap blob (e.g., during mount).
+ */
+struct ceph_monmap *ceph_monmap_decode(void *p, void *end)
+{
+        struct ceph_monmap *m = NULL;
+        int i, err = -EINVAL;
+        struct ceph_fsid fsid;
+        u32 epoch, num_mon;
+        u16 version;
+        u32 len;
+
+        ceph_decode_32_safe(&p, end, len, bad);
+        ceph_decode_need(&p, end, len, bad);
+
+        dout("monmap_decode %p %p len %d\n", p, end, (int)(end-p));
+
+        ceph_decode_16_safe(&p, end, version, bad);
+
+        ceph_decode_need(&p, end, sizeof(fsid) + 2*sizeof(u32), bad);
+        ceph_decode_copy(&p, &fsid, sizeof(fsid));
+        epoch = ceph_decode_32(&p);
+
+        num_mon = ceph_decode_32(&p);
+        ceph_decode_need(&p, end, num_mon*sizeof(m->mon_inst[0]), bad);
+
+        if (num_mon >= CEPH_MAX_MON)
+                goto bad;
+        m = kmalloc(sizeof(*m) + sizeof(m->mon_inst[0])*num_mon, GFP_NOFS);
+        if (m == NULL)
+                return ERR_PTR(-ENOMEM);
+        m->fsid = fsid;
+        m->epoch = epoch;
+        m->num_mon = num_mon;
+        ceph_decode_copy(&p, m->mon_inst, num_mon*sizeof(m->mon_inst[0]));
+        for (i = 0; i < num_mon; i++)
+                ceph_decode_addr(&m->mon_inst[i].addr);
+
+        dout("monmap_decode epoch %d, num_mon %d\n", m->epoch,
+             m->num_mon);
+        for (i = 0; i < m->num_mon; i++)
+                dout("monmap_decode  mon%d is %s\n", i,
+                     ceph_pr_addr(&m->mon_inst[i].addr.in_addr));
+        return m;
+
+bad:
+        dout("monmap_decode failed with %d\n", err);
+        kfree(m);
+        return ERR_PTR(err);
+}
+
+/*
+ * return true if *addr is included in the monmap.
+ */
+int ceph_monmap_contains(struct ceph_monmap *m, struct ceph_entity_addr *addr)
+{
+        int i;
+
+        for (i = 0; i < m->num_mon; i++)
+                if (memcmp(addr, &m->mon_inst[i].addr, sizeof(*addr)) == 0)
+                        return 1;
+        return 0;
+}
+
+/*
+ * Send an auth request.
+ */
+static void __send_prepared_auth_request(struct ceph_mon_client *monc, int len)
+{
+        monc->pending_auth = 1;
+        monc->m_auth->front.iov_len = len;
+        monc->m_auth->hdr.front_len = cpu_to_le32(len);
+        ceph_con_revoke(monc->con, monc->m_auth);
+        ceph_msg_get(monc->m_auth);  /* keep our ref */
+        ceph_con_send(monc->con, monc->m_auth);
+}
+
+/*
+ * Close monitor session, if any.
+ */
+static void __close_session(struct ceph_mon_client *monc)
+{
+        if (monc->con) {
+                dout("__close_session closing mon%d\n", monc->cur_mon);
+                ceph_con_revoke(monc->con, monc->m_auth);
+                ceph_con_close(monc->con);
+                monc->cur_mon = -1;
+                monc->pending_auth = 0;
+                ceph_auth_reset(monc->auth);
+        }
+}
+
+/*
+ * Open a session with a (new) monitor.
+ */
+static int __open_session(struct ceph_mon_client *monc)
+{
+        char r;
+        int ret;
+
+        if (monc->cur_mon < 0) {
+                get_random_bytes(&r, 1);
+                monc->cur_mon = r % monc->monmap->num_mon;
+                dout("open_session num=%d r=%d -> mon%d\n",
+                     monc->monmap->num_mon, r, monc->cur_mon);
+                monc->sub_sent = 0;
+                monc->sub_renew_after = jiffies;  /* i.e., expired */
+                monc->want_next_osdmap = !!monc->want_next_osdmap;
+
+                dout("open_session mon%d opening\n", monc->cur_mon);
+                monc->con->peer_name.type = CEPH_ENTITY_TYPE_MON;
+                monc->con->peer_name.num = cpu_to_le64(monc->cur_mon);
+                ceph_con_open(monc->con,
+                              &monc->monmap->mon_inst[monc->cur_mon].addr);
+
+                /* initiatiate authentication handshake */
+                ret = ceph_auth_build_hello(monc->auth,
+                                            monc->m_auth->front.iov_base,
+                                            monc->m_auth->front_max);
+                __send_prepared_auth_request(monc, ret);
+        } else {
+                dout("open_session mon%d already open\n", monc->cur_mon);
+        }
+        return 0;
+}
+
+static bool __sub_expired(struct ceph_mon_client *monc)
+{
+        return time_after_eq(jiffies, monc->sub_renew_after);
+}
+
+/*
+ * Reschedule delayed work timer.
+ */
+static void __schedule_delayed(struct ceph_mon_client *monc)
+{
+        unsigned delay;
+
+        if (monc->cur_mon < 0 || __sub_expired(monc))
+                delay = 10 * HZ;
+        else
+                delay = 20 * HZ;
+        dout("__schedule_delayed after %u\n", delay);
+        schedule_delayed_work(&monc->delayed_work, delay);
+}
+
+/*
+ * Send subscribe request for mdsmap and/or osdmap.
+ */
+static void __send_subscribe(struct ceph_mon_client *monc)
+{
+        dout("__send_subscribe sub_sent=%u exp=%u want_osd=%d\n",
+             (unsigned)monc->sub_sent, __sub_expired(monc),
+             monc->want_next_osdmap);
+        if ((__sub_expired(monc) && !monc->sub_sent) ||
+            monc->want_next_osdmap == 1) {
+                struct ceph_msg *msg = monc->m_subscribe;
+                struct ceph_mon_subscribe_item *i;
+                void *p, *end;
+                int num;
+
+                p = msg->front.iov_base;
+                end = p + msg->front_max;
+
+                num = 1 + !!monc->want_next_osdmap + !!monc->want_mdsmap;
+                ceph_encode_32(&p, num);
+
+                if (monc->want_next_osdmap) {
+                        dout("__send_subscribe to 'osdmap' %u\n",
+                             (unsigned)monc->have_osdmap);
+                        ceph_encode_string(&p, end, "osdmap", 6);
+                        i = p;
+                        i->have = cpu_to_le64(monc->have_osdmap);
+                        i->onetime = 1;
+                        p += sizeof(*i);
+                        monc->want_next_osdmap = 2;  /* requested */
+                }
+                if (monc->want_mdsmap) {
+                        dout("__send_subscribe to 'mdsmap' %u+\n",
+                             (unsigned)monc->have_mdsmap);
+                        ceph_encode_string(&p, end, "mdsmap", 6);
+                        i = p;
+                        i->have = cpu_to_le64(monc->have_mdsmap);
+                        i->onetime = 0;
+                        p += sizeof(*i);
+                }
+                ceph_encode_string(&p, end, "monmap", 6);
+                i = p;
+                i->have = 0;
+                i->onetime = 0;
+                p += sizeof(*i);
+
+                msg->front.iov_len = p - msg->front.iov_base;
+                msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
+                ceph_con_revoke(monc->con, msg);
+                ceph_con_send(monc->con, ceph_msg_get(msg));
+
+                monc->sub_sent = jiffies | 1;  /* never 0 */
+        }
+}
+
+static void handle_subscribe_ack(struct ceph_mon_client *monc,
+                                 struct ceph_msg *msg)
+{
+        unsigned seconds;
+        struct ceph_mon_subscribe_ack *h = msg->front.iov_base;
+
+        if (msg->front.iov_len < sizeof(*h))
+                goto bad;
+        seconds = le32_to_cpu(h->duration);
+
+        mutex_lock(&monc->mutex);
+        if (monc->hunting) {
+                pr_info("mon%d %s session established\n",
+                        monc->cur_mon,
+                        ceph_pr_addr(&monc->con->peer_addr.in_addr));
+                monc->hunting = false;
+        }
+        dout("handle_subscribe_ack after %d seconds\n", seconds);
+        monc->sub_renew_after = monc->sub_sent + (seconds >> 1)*HZ - 1;
+        monc->sub_sent = 0;
+        mutex_unlock(&monc->mutex);
+        return;
+bad:
+        pr_err("got corrupt subscribe-ack msg\n");
+        ceph_msg_dump(msg);
+}
+
+/*
+ * Keep track of which maps we have
+ */
+int ceph_monc_got_mdsmap(struct ceph_mon_client *monc, u32 got)
+{
+        mutex_lock(&monc->mutex);
+        monc->have_mdsmap = got;
+        mutex_unlock(&monc->mutex);
+        return 0;
+}
+EXPORT_SYMBOL(ceph_monc_got_mdsmap);
+
+int ceph_monc_got_osdmap(struct ceph_mon_client *monc, u32 got)
+{
+        mutex_lock(&monc->mutex);
+        monc->have_osdmap = got;
+        monc->want_next_osdmap = 0;
+        mutex_unlock(&monc->mutex);
+        return 0;
+}
+
+/*
+ * Register interest in the next osdmap
+ */
+void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc)
+{
+        dout("request_next_osdmap have %u\n", monc->have_osdmap);
+        mutex_lock(&monc->mutex);
+        if (!monc->want_next_osdmap)
+                monc->want_next_osdmap = 1;
+        if (monc->want_next_osdmap < 2)
+                __send_subscribe(monc);
+        mutex_unlock(&monc->mutex);
+}
+
+/*
+ *
+ */
+int ceph_monc_open_session(struct ceph_mon_client *monc)
+{
+        if (!monc->con) {
+                monc->con = kmalloc(sizeof(*monc->con), GFP_KERNEL);
+                if (!monc->con)
+                        return -ENOMEM;
+                ceph_con_init(monc->client->msgr, monc->con);
+                monc->con->private = monc;
+                monc->con->ops = &mon_con_ops;
+        }
+
+        mutex_lock(&monc->mutex);
+        __open_session(monc);
+        __schedule_delayed(monc);
+        mutex_unlock(&monc->mutex);
+        return 0;
+}
+EXPORT_SYMBOL(ceph_monc_open_session);
+
+/*
+ * The monitor responds with mount ack indicate mount success.  The
+ * included client ticket allows the client to talk to MDSs and OSDs.
+ */
+static void ceph_monc_handle_map(struct ceph_mon_client *monc,
+                                 struct ceph_msg *msg)
+{
+        struct ceph_client *client = monc->client;
+        struct ceph_monmap *monmap = NULL, *old = monc->monmap;
+        void *p, *end;
+
+        mutex_lock(&monc->mutex);
+
+        dout("handle_monmap\n");
+        p = msg->front.iov_base;
+        end = p + msg->front.iov_len;
+
+        monmap = ceph_monmap_decode(p, end);
+        if (IS_ERR(monmap)) {
+                pr_err("problem decoding monmap, %d\n",
+                       (int)PTR_ERR(monmap));
+                goto out;
+        }
+
+        if (ceph_check_fsid(monc->client, &monmap->fsid) < 0) {
+                kfree(monmap);
+                goto out;
+        }
+
+        client->monc.monmap = monmap;
+        kfree(old);
+
+out:
+        mutex_unlock(&monc->mutex);
+        wake_up_all(&client->auth_wq);
+}
+
+/*
+ * generic requests (e.g., statfs, poolop)
+ */
+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);
+}
+
+static void release_generic_request(struct kref *kref)
+{
+        struct ceph_mon_generic_request *req =
+                container_of(kref, struct ceph_mon_generic_request, kref);
+
+        if (req->reply)
+                ceph_msg_put(req->reply);
+        if (req->request)
+                ceph_msg_put(req->request);
+
+        kfree(req);
+}
+
+static void put_generic_request(struct ceph_mon_generic_request *req)
+{
+        kref_put(&req->kref, release_generic_request);
+}
+
+static void get_generic_request(struct ceph_mon_generic_request *req)
+{
+        kref_get(&req->kref);
+}
+
+static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
+                                         struct ceph_msg_header *hdr,
+                                         int *skip)
+{
+        struct ceph_mon_client *monc = con->private;
+        struct ceph_mon_generic_request *req;
+        u64 tid = le64_to_cpu(hdr->tid);
+        struct ceph_msg *m;
+
+        mutex_lock(&monc->mutex);
+        req = __lookup_generic_req(monc, tid);
+        if (!req) {
+                dout("get_generic_reply %lld dne\n", tid);
+                *skip = 1;
+                m = NULL;
+        } else {
+                dout("get_generic_reply %lld got %p\n", tid, req->reply);
+                m = ceph_msg_get(req->reply);
+                /*
+                 * we don't need to track the connection reading into
+                 * this reply because we only have one open connection
+                 * at a time, ever.
+                 */
+        }
+        mutex_unlock(&monc->mutex);
+        return m;
+}
+
+static int do_generic_request(struct ceph_mon_client *monc,
+                              struct ceph_mon_generic_request *req)
+{
+        int err;
+
+        /* register request */
+        mutex_lock(&monc->mutex);
+        req->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--;
+        mutex_unlock(&monc->mutex);
+
+        if (!err)
+                err = req->result;
+        return err;
+}
+
+/*
+ * statfs
+ */
+static void handle_statfs_reply(struct ceph_mon_client *monc,
+                                struct ceph_msg *msg)
+{
+        struct ceph_mon_generic_request *req;
+        struct ceph_mon_statfs_reply *reply = msg->front.iov_base;
+        u64 tid = le64_to_cpu(msg->hdr.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);
+        }
+        mutex_unlock(&monc->mutex);
+        if (req) {
+                complete_all(&req->completion);
+                put_generic_request(req);
+        }
+        return;
+
+bad:
+        pr_err("corrupt generic reply, tid %llu\n", tid);
+        ceph_msg_dump(msg);
+}
+
+/*
+ * Do a synchronous statfs().
+ */
+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;
+
+        req = kzalloc(sizeof(*req), GFP_NOFS);
+        if (!req)
+                return -ENOMEM;
+
+        kref_init(&req->kref);
+        req->buf = buf;
+        req->buf_len = sizeof(*buf);
+        init_completion(&req->completion);
+
+        err = -ENOMEM;
+        req->request = ceph_msg_new(CEPH_MSG_STATFS, sizeof(*h), GFP_NOFS);
+        if (!req->request)
+                goto out;
+        req->reply = ceph_msg_new(CEPH_MSG_STATFS_REPLY, 1024, GFP_NOFS);
+        if (!req->reply)
+                goto out;
+
+        /* 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;
+
+        err = do_generic_request(monc, req);
+
+out:
+        kref_put(&req->kref, release_generic_request);
+        return err;
+}
+EXPORT_SYMBOL(ceph_monc_do_statfs);
+
+/*
+ * pool ops
+ */
+static int get_poolop_reply_buf(const char *src, size_t src_len,
+                                char *dst, size_t dst_len)
+{
+        u32 buf_len;
+
+        if (src_len != sizeof(u32) + dst_len)
+                return -EINVAL;
+
+        buf_len = le32_to_cpu(*(u32 *)src);
+        if (buf_len != dst_len)
+                return -EINVAL;
+
+        memcpy(dst, src + sizeof(u32), dst_len);
+        return 0;
+}
+
+static void handle_poolop_reply(struct ceph_mon_client *monc,
+                                struct ceph_msg *msg)
+{
+        struct ceph_mon_generic_request *req;
+        struct ceph_mon_poolop_reply *reply = msg->front.iov_base;
+        u64 tid = le64_to_cpu(msg->hdr.tid);
+
+        if (msg->front.iov_len < sizeof(*reply))
+                goto bad;
+        dout("handle_poolop_reply %p tid %llu\n", msg, tid);
+
+        mutex_lock(&monc->mutex);
+        req = __lookup_generic_req(monc, tid);
+        if (req) {
+                if (req->buf_len &&
+                    get_poolop_reply_buf(msg->front.iov_base + sizeof(*reply),
+                                     msg->front.iov_len - sizeof(*reply),
+                                     req->buf, req->buf_len) < 0) {
+                        mutex_unlock(&monc->mutex);
+                        goto bad;
+                }
+                req->result = le32_to_cpu(reply->reply_code);
+                get_generic_request(req);
+        }
+        mutex_unlock(&monc->mutex);
+        if (req) {
+                complete(&req->completion);
+                put_generic_request(req);
+        }
+        return;
+
+bad:
+        pr_err("corrupt generic reply, tid %llu\n", tid);
+        ceph_msg_dump(msg);
+}
+
+/*
+ * Do a synchronous pool op.
+ */
+int ceph_monc_do_poolop(struct ceph_mon_client *monc, u32 op,
+                        u32 pool, u64 snapid,
+                        char *buf, int len)
+{
+        struct ceph_mon_generic_request *req;
+        struct ceph_mon_poolop *h;
+        int err;
+
+        req = kzalloc(sizeof(*req), GFP_NOFS);
+        if (!req)
+                return -ENOMEM;
+
+        kref_init(&req->kref);
+        req->buf = buf;
+        req->buf_len = len;
+        init_completion(&req->completion);
+
+        err = -ENOMEM;
+        req->request = ceph_msg_new(CEPH_MSG_POOLOP, sizeof(*h), GFP_NOFS);
+        if (!req->request)
+                goto out;
+        req->reply = ceph_msg_new(CEPH_MSG_POOLOP_REPLY, 1024, GFP_NOFS);
+        if (!req->reply)
+                goto out;
+
+        /* fill out request */
+        req->request->hdr.version = cpu_to_le16(2);
+        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;
+        h->pool = cpu_to_le32(pool);
+        h->op = cpu_to_le32(op);
+        h->auid = 0;
+        h->snapid = cpu_to_le64(snapid);
+        h->name_len = 0;
+
+        err = do_generic_request(monc, req);
+
+out:
+        kref_put(&req->kref, release_generic_request);
+        return err;
+}
+
+int ceph_monc_create_snapid(struct ceph_mon_client *monc,
+                            u32 pool, u64 *snapid)
+{
+        return ceph_monc_do_poolop(monc,  POOL_OP_CREATE_UNMANAGED_SNAP,
+                                   pool, 0, (char *)snapid, sizeof(*snapid));
+
+}
+EXPORT_SYMBOL(ceph_monc_create_snapid);
+
+int ceph_monc_delete_snapid(struct ceph_mon_client *monc,
+                            u32 pool, u64 snapid)
+{
+        return ceph_monc_do_poolop(monc,  POOL_OP_CREATE_UNMANAGED_SNAP,
+                                   pool, snapid, 0, 0);
+
+}
+
+/*
+ * Resend pending generic requests.
+ */
+static void __resend_generic_request(struct ceph_mon_client *monc)
+{
+        struct ceph_mon_generic_request *req;
+        struct rb_node *p;
+
+        for (p = rb_first(&monc->generic_request_tree); p; p = rb_next(p)) {
+                req = rb_entry(p, struct ceph_mon_generic_request, node);
+                ceph_con_revoke(monc->con, req->request);
+                ceph_con_send(monc->con, ceph_msg_get(req->request));
+        }
+}
+
+/*
+ * Delayed work.  If we haven't mounted yet, retry.  Otherwise,
+ * renew/retry subscription as needed (in case it is timing out, or we
+ * got an ENOMEM).  And keep the monitor connection alive.
+ */
+static void delayed_work(struct work_struct *work)
+{
+        struct ceph_mon_client *monc =
+                container_of(work, struct ceph_mon_client, delayed_work.work);
+
+        dout("monc delayed_work\n");
+        mutex_lock(&monc->mutex);
+        if (monc->hunting) {
+                __close_session(monc);
+                __open_session(monc);  /* continue hunting */
+        } else {
+                ceph_con_keepalive(monc->con);
+
+                __validate_auth(monc);
+
+                if (monc->auth->ops->is_authenticated(monc->auth))
+                        __send_subscribe(monc);
+        }
+        __schedule_delayed(monc);
+        mutex_unlock(&monc->mutex);
+}
+
+/*
+ * On startup, we build a temporary monmap populated with the IPs
+ * provided by mount(2).
+ */
+static int build_initial_monmap(struct ceph_mon_client *monc)
+{
+        struct ceph_options *opt = monc->client->options;
+        struct ceph_entity_addr *mon_addr = opt->mon_addr;
+        int num_mon = opt->num_mon;
+        int i;
+
+        /* build initial monmap */
+        monc->monmap = kzalloc(sizeof(*monc->monmap) +
+                               num_mon*sizeof(monc->monmap->mon_inst[0]),
+                               GFP_KERNEL);
+        if (!monc->monmap)
+                return -ENOMEM;
+        for (i = 0; i < num_mon; i++) {
+                monc->monmap->mon_inst[i].addr = mon_addr[i];
+                monc->monmap->mon_inst[i].addr.nonce = 0;
+                monc->monmap->mon_inst[i].name.type =
+                        CEPH_ENTITY_TYPE_MON;
+                monc->monmap->mon_inst[i].name.num = cpu_to_le64(i);
+        }
+        monc->monmap->num_mon = num_mon;
+        monc->have_fsid = false;
+        return 0;
+}
+
+int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
+{
+        int err = 0;
+
+        dout("init\n");
+        memset(monc, 0, sizeof(*monc));
+        monc->client = cl;
+        monc->monmap = NULL;
+        mutex_init(&monc->mutex);
+
+        err = build_initial_monmap(monc);
+        if (err)
+                goto out;
+
+        monc->con = NULL;
+
+        /* authentication */
+        monc->auth = ceph_auth_init(cl->options->name,
+                                    cl->options->secret);
+        if (IS_ERR(monc->auth))
+                return PTR_ERR(monc->auth);
+        monc->auth->want_keys =
+                CEPH_ENTITY_TYPE_AUTH | CEPH_ENTITY_TYPE_MON |
+                CEPH_ENTITY_TYPE_OSD | CEPH_ENTITY_TYPE_MDS;
+
+        /* msgs */
+        err = -ENOMEM;
+        monc->m_subscribe_ack = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE_ACK,
+                                     sizeof(struct ceph_mon_subscribe_ack),
+                                     GFP_NOFS);
+        if (!monc->m_subscribe_ack)
+                goto out_monmap;
+
+        monc->m_subscribe = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 96, GFP_NOFS);
+        if (!monc->m_subscribe)
+                goto out_subscribe_ack;
+
+        monc->m_auth_reply = ceph_msg_new(CEPH_MSG_AUTH_REPLY, 4096, GFP_NOFS);
+        if (!monc->m_auth_reply)
+                goto out_subscribe;
+
+        monc->m_auth = ceph_msg_new(CEPH_MSG_AUTH, 4096, GFP_NOFS);
+        monc->pending_auth = 0;
+        if (!monc->m_auth)
+                goto out_auth_reply;
+
+        monc->cur_mon = -1;
+        monc->hunting = true;
+        monc->sub_renew_after = jiffies;
+        monc->sub_sent = 0;
+
+        INIT_DELAYED_WORK(&monc->delayed_work, delayed_work);
+        monc->generic_request_tree = RB_ROOT;
+        monc->num_generic_requests = 0;
+        monc->last_tid = 0;
+
+        monc->have_mdsmap = 0;
+        monc->have_osdmap = 0;
+        monc->want_next_osdmap = 1;
+        return 0;
+
+out_auth_reply:
+        ceph_msg_put(monc->m_auth_reply);
+out_subscribe:
+        ceph_msg_put(monc->m_subscribe);
+out_subscribe_ack:
+        ceph_msg_put(monc->m_subscribe_ack);
+out_monmap:
+        kfree(monc->monmap);
+out:
+        return err;
+}
+EXPORT_SYMBOL(ceph_monc_init);
+
+void ceph_monc_stop(struct ceph_mon_client *monc)
+{
+        dout("stop\n");
+        cancel_delayed_work_sync(&monc->delayed_work);
+
+        mutex_lock(&monc->mutex);
+        __close_session(monc);
+        if (monc->con) {
+                monc->con->private = NULL;
+                monc->con->ops->put(monc->con);
+                monc->con = NULL;
+        }
+        mutex_unlock(&monc->mutex);
+
+        ceph_auth_destroy(monc->auth);
+
+        ceph_msg_put(monc->m_auth);
+        ceph_msg_put(monc->m_auth_reply);
+        ceph_msg_put(monc->m_subscribe);
+        ceph_msg_put(monc->m_subscribe_ack);
+
+        kfree(monc->monmap);
+}
+EXPORT_SYMBOL(ceph_monc_stop);
+
+static void handle_auth_reply(struct ceph_mon_client *monc,
+                              struct ceph_msg *msg)
+{
+        int ret;
+        int was_auth = 0;
+
+        mutex_lock(&monc->mutex);
+        if (monc->auth->ops)
+                was_auth = monc->auth->ops->is_authenticated(monc->auth);
+        monc->pending_auth = 0;
+        ret = ceph_handle_auth_reply(monc->auth, msg->front.iov_base,
+                                     msg->front.iov_len,
+                                     monc->m_auth->front.iov_base,
+                                     monc->m_auth->front_max);
+        if (ret < 0) {
+                monc->client->auth_err = ret;
+                wake_up_all(&monc->client->auth_wq);
+        } else if (ret > 0) {
+                __send_prepared_auth_request(monc, ret);
+        } else if (!was_auth && monc->auth->ops->is_authenticated(monc->auth)) {
+                dout("authenticated, starting session\n");
+
+                monc->client->msgr->inst.name.type = CEPH_ENTITY_TYPE_CLIENT;
+                monc->client->msgr->inst.name.num =
+                                        cpu_to_le64(monc->auth->global_id);
+
+                __send_subscribe(monc);
+                __resend_generic_request(monc);
+        }
+        mutex_unlock(&monc->mutex);
+}
+
+static int __validate_auth(struct ceph_mon_client *monc)
+{
+        int ret;
+
+        if (monc->pending_auth)
+                return 0;
+
+        ret = ceph_build_auth(monc->auth, monc->m_auth->front.iov_base,
+                              monc->m_auth->front_max);
+        if (ret <= 0)
+                return ret; /* either an error, or no need to authenticate */
+        __send_prepared_auth_request(monc, ret);
+        return 0;
+}
+
+int ceph_monc_validate_auth(struct ceph_mon_client *monc)
+{
+        int ret;
+
+        mutex_lock(&monc->mutex);
+        ret = __validate_auth(monc);
+        mutex_unlock(&monc->mutex);
+        return ret;
+}
+EXPORT_SYMBOL(ceph_monc_validate_auth);
+
+/*
+ * handle incoming message
+ */
+static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
+{
+        struct ceph_mon_client *monc = con->private;
+        int type = le16_to_cpu(msg->hdr.type);
+
+        if (!monc)
+                return;
+
+        switch (type) {
+        case CEPH_MSG_AUTH_REPLY:
+                handle_auth_reply(monc, msg);
+                break;
+
+        case CEPH_MSG_MON_SUBSCRIBE_ACK:
+                handle_subscribe_ack(monc, msg);
+                break;
+
+        case CEPH_MSG_STATFS_REPLY:
+                handle_statfs_reply(monc, msg);
+                break;
+
+        case CEPH_MSG_POOLOP_REPLY:
+                handle_poolop_reply(monc, msg);
+                break;
+
+        case CEPH_MSG_MON_MAP:
+                ceph_monc_handle_map(monc, msg);
+                break;
+
+        case CEPH_MSG_OSD_MAP:
+                ceph_osdc_handle_map(&monc->client->osdc, msg);
+                break;
+
+        default:
+                /* can the chained handler handle it? */
+                if (monc->client->extra_mon_dispatch &&
+                    monc->client->extra_mon_dispatch(monc->client, msg) == 0)
+                        break;
+                        
+                pr_err("received unknown message type %d %s\n", type,
+                       ceph_msg_type_name(type));
+        }
+        ceph_msg_put(msg);
+}
+
+/*
+ * Allocate memory for incoming message
+ */
+static struct ceph_msg *mon_alloc_msg(struct ceph_connection *con,
+                                      struct ceph_msg_header *hdr,
+                                      int *skip)
+{
+        struct ceph_mon_client *monc = con->private;
+        int type = le16_to_cpu(hdr->type);
+        int front_len = le32_to_cpu(hdr->front_len);
+        struct ceph_msg *m = NULL;
+
+        *skip = 0;
+
+        switch (type) {
+        case CEPH_MSG_MON_SUBSCRIBE_ACK:
+                m = ceph_msg_get(monc->m_subscribe_ack);
+                break;
+        case CEPH_MSG_POOLOP_REPLY:
+        case CEPH_MSG_STATFS_REPLY:
+                return get_generic_reply(con, hdr, skip);
+        case CEPH_MSG_AUTH_REPLY:
+                m = ceph_msg_get(monc->m_auth_reply);
+                break;
+        case CEPH_MSG_MON_MAP:
+        case CEPH_MSG_MDS_MAP:
+        case CEPH_MSG_OSD_MAP:
+                m = ceph_msg_new(type, front_len, GFP_NOFS);
+                break;
+        }
+
+        if (!m) {
+                pr_info("alloc_msg unknown type %d\n", type);
+                *skip = 1;
+        }
+        return m;
+}
+
+/*
+ * If the monitor connection resets, pick a new monitor and resubmit
+ * any pending requests.
+ */
+static void mon_fault(struct ceph_connection *con)
+{
+        struct ceph_mon_client *monc = con->private;
+
+        if (!monc)
+                return;
+
+        dout("mon_fault\n");
+        mutex_lock(&monc->mutex);
+        if (!con->private)
+                goto out;
+
+        if (monc->con && !monc->hunting)
+                pr_info("mon%d %s session lost, "
+                        "hunting for new mon\n", monc->cur_mon,
+                        ceph_pr_addr(&monc->con->peer_addr.in_addr));
+
+        __close_session(monc);
+        if (!monc->hunting) {
+                /* start hunting */
+                monc->hunting = true;
+                __open_session(monc);
+        } else {
+                /* already hunting, let's wait a bit */
+                __schedule_delayed(monc);
+        }
+out:
+        mutex_unlock(&monc->mutex);
+}
+
+static const struct ceph_connection_operations mon_con_ops = {
+        .get = ceph_con_get,
+        .put = ceph_con_put,
+        .dispatch = dispatch,
+        .fault = mon_fault,
+        .alloc_msg = mon_alloc_msg,
+};