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-rw-r--r--net/ceph/mon_client.c1121
1 files changed, 1121 insertions, 0 deletions
diff --git a/net/ceph/mon_client.c b/net/ceph/mon_client.c
new file mode 100644
index 000000000..2b3cf05e8
--- /dev/null
+++ b/net/ceph/mon_client.c
@@ -0,0 +1,1121 @@
+#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/debugfs.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_msg_revoke(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)
+{
+ dout("__close_session closing mon%d\n", monc->cur_mon);
+ ceph_msg_revoke(monc->m_auth);
+ ceph_msg_revoke_incoming(monc->m_auth_reply);
+ ceph_msg_revoke(monc->m_subscribe);
+ ceph_msg_revoke_incoming(monc->m_subscribe_ack);
+ 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);
+ ceph_con_open(&monc->con,
+ CEPH_ENTITY_TYPE_MON, monc->cur_mon,
+ &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_alloc_len);
+ __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 int 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 int)monc->sub_sent, __sub_expired(monc),
+ monc->want_next_osdmap);
+ if ((__sub_expired(monc) && !monc->sub_sent) ||
+ monc->want_next_osdmap == 1) {
+ struct ceph_msg *msg = monc->m_subscribe;
+ struct ceph_mon_subscribe_item *i;
+ void *p, *end;
+ int num;
+
+ p = msg->front.iov_base;
+ end = p + msg->front_alloc_len;
+
+ 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 int)monc->have_osdmap);
+ ceph_encode_string(&p, end, "osdmap", 6);
+ i = p;
+ i->have = cpu_to_le64(monc->have_osdmap);
+ i->onetime = 1;
+ p += sizeof(*i);
+ monc->want_next_osdmap = 2; /* requested */
+ }
+ if (monc->want_mdsmap) {
+ dout("__send_subscribe to 'mdsmap' %u+\n",
+ (unsigned int)monc->have_mdsmap);
+ ceph_encode_string(&p, end, "mdsmap", 6);
+ i = p;
+ i->have = cpu_to_le64(monc->have_mdsmap);
+ i->onetime = 0;
+ p += sizeof(*i);
+ }
+ ceph_encode_string(&p, end, "monmap", 6);
+ i = p;
+ i->have = 0;
+ i->onetime = 0;
+ p += sizeof(*i);
+
+ msg->front.iov_len = p - msg->front.iov_base;
+ msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
+ ceph_msg_revoke(msg);
+ ceph_con_send(&monc->con, ceph_msg_get(msg));
+
+ monc->sub_sent = jiffies | 1; /* never 0 */
+ }
+}
+
+static void handle_subscribe_ack(struct ceph_mon_client *monc,
+ struct ceph_msg *msg)
+{
+ unsigned int 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);
+}
+EXPORT_SYMBOL(ceph_monc_request_next_osdmap);
+
+int ceph_monc_wait_osdmap(struct ceph_mon_client *monc, u32 epoch,
+ unsigned long timeout)
+{
+ unsigned long started = jiffies;
+ int ret;
+
+ mutex_lock(&monc->mutex);
+ while (monc->have_osdmap < epoch) {
+ mutex_unlock(&monc->mutex);
+
+ if (timeout != 0 && time_after_eq(jiffies, started + timeout))
+ return -ETIMEDOUT;
+
+ ret = wait_event_interruptible_timeout(monc->client->auth_wq,
+ monc->have_osdmap >= epoch, timeout);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&monc->mutex);
+ }
+
+ mutex_unlock(&monc->mutex);
+ return 0;
+}
+EXPORT_SYMBOL(ceph_monc_wait_osdmap);
+
+/*
+ *
+ */
+int ceph_monc_open_session(struct ceph_mon_client *monc)
+{
+ mutex_lock(&monc->mutex);
+ __open_session(monc);
+ __schedule_delayed(monc);
+ mutex_unlock(&monc->mutex);
+ return 0;
+}
+EXPORT_SYMBOL(ceph_monc_open_session);
+
+/*
+ * We require the fsid and global_id in order to initialize our
+ * debugfs dir.
+ */
+static bool have_debugfs_info(struct ceph_mon_client *monc)
+{
+ dout("have_debugfs_info fsid %d globalid %lld\n",
+ (int)monc->client->have_fsid, monc->auth->global_id);
+ return monc->client->have_fsid && monc->auth->global_id > 0;
+}
+
+/*
+ * 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;
+ int had_debugfs_info, init_debugfs = 0;
+
+ mutex_lock(&monc->mutex);
+
+ had_debugfs_info = have_debugfs_info(monc);
+
+ 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);
+
+ if (!client->have_fsid) {
+ client->have_fsid = true;
+ if (!had_debugfs_info && have_debugfs_info(monc)) {
+ pr_info("client%lld fsid %pU\n",
+ ceph_client_id(monc->client),
+ &monc->client->fsid);
+ init_debugfs = 1;
+ }
+ mutex_unlock(&monc->mutex);
+
+ if (init_debugfs) {
+ /*
+ * do debugfs initialization without mutex to avoid
+ * creating a locking dependency
+ */
+ ceph_debugfs_client_init(monc->client);
+ }
+
+ goto out_unlocked;
+ }
+out:
+ mutex_unlock(&monc->mutex);
+out_unlocked:
+ wake_up_all(&client->auth_wq);
+}
+
+/*
+ * 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);
+}
+
+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);
+ *skip = 0;
+ 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, 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
+ */
+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 statfs 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;
+ init_completion(&req->completion);
+
+ 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);
+ 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:
+ put_generic_request(req);
+ return err;
+}
+EXPORT_SYMBOL(ceph_monc_do_statfs);
+
+static void handle_get_version_reply(struct ceph_mon_client *monc,
+ struct ceph_msg *msg)
+{
+ struct ceph_mon_generic_request *req;
+ u64 tid = le64_to_cpu(msg->hdr.tid);
+ void *p = msg->front.iov_base;
+ void *end = p + msg->front_alloc_len;
+ u64 handle;
+
+ dout("%s %p tid %llu\n", __func__, msg, tid);
+
+ ceph_decode_need(&p, end, 2*sizeof(u64), bad);
+ handle = ceph_decode_64(&p);
+ if (tid != 0 && tid != handle)
+ 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);
+ }
+ mutex_unlock(&monc->mutex);
+ if (req) {
+ complete_all(&req->completion);
+ put_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)
+{
+ struct ceph_mon_generic_request *req;
+ void *p, *end;
+ u64 tid;
+ int err;
+
+ req = kzalloc(sizeof(*req), GFP_NOFS);
+ if (!req)
+ return -ENOMEM;
+
+ kref_init(&req->kref);
+ req->buf = newest;
+ init_completion(&req->completion);
+
+ 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;
+ }
+
+ req->reply = ceph_msg_new(CEPH_MSG_MON_GET_VERSION_REPLY, 1024,
+ GFP_NOFS, true);
+ if (!req->reply) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ p = req->request->front.iov_base;
+ end = p + req->request->front_alloc_len;
+
+ /* 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));
+
+ err = __do_generic_request(monc, tid, req);
+
+ mutex_unlock(&monc->mutex);
+out:
+ put_generic_request(req);
+ return err;
+}
+EXPORT_SYMBOL(ceph_monc_do_get_version);
+
+/*
+ * 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_msg_revoke(req->request);
+ ceph_msg_revoke_incoming(req->reply);
+ 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 (ceph_auth_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;
+ 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;
+
+ /* connection */
+ /* authentication */
+ monc->auth = ceph_auth_init(cl->options->name,
+ cl->options->key);
+ if (IS_ERR(monc->auth)) {
+ err = PTR_ERR(monc->auth);
+ goto out_monmap;
+ }
+ 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, true);
+ if (!monc->m_subscribe_ack)
+ goto out_auth;
+
+ monc->m_subscribe = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 96, GFP_NOFS,
+ true);
+ if (!monc->m_subscribe)
+ goto out_subscribe_ack;
+
+ monc->m_auth_reply = ceph_msg_new(CEPH_MSG_AUTH_REPLY, 4096, GFP_NOFS,
+ true);
+ if (!monc->m_auth_reply)
+ goto out_subscribe;
+
+ monc->m_auth = ceph_msg_new(CEPH_MSG_AUTH, 4096, GFP_NOFS, true);
+ monc->pending_auth = 0;
+ if (!monc->m_auth)
+ goto out_auth_reply;
+
+ ceph_con_init(&monc->con, monc, &mon_con_ops,
+ &monc->client->msgr);
+
+ 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_auth:
+ ceph_auth_destroy(monc->auth);
+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);
+
+ mutex_unlock(&monc->mutex);
+
+ /*
+ * flush msgr queue before we destroy ourselves to ensure that:
+ * - any work that references our embedded con is finished.
+ * - any osd_client or other work that may reference an authorizer
+ * finishes before we shut down the auth subsystem.
+ */
+ ceph_msgr_flush();
+
+ 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;
+ int had_debugfs_info, init_debugfs = 0;
+
+ mutex_lock(&monc->mutex);
+ had_debugfs_info = have_debugfs_info(monc);
+ was_auth = ceph_auth_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_alloc_len);
+ 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 && ceph_auth_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);
+ }
+
+ if (!had_debugfs_info && have_debugfs_info(monc)) {
+ pr_info("client%lld fsid %pU\n",
+ ceph_client_id(monc->client),
+ &monc->client->fsid);
+ init_debugfs = 1;
+ }
+ mutex_unlock(&monc->mutex);
+
+ if (init_debugfs) {
+ /*
+ * do debugfs initialization without mutex to avoid
+ * creating a locking dependency
+ */
+ ceph_debugfs_client_init(monc->client);
+ }
+}
+
+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_alloc_len);
+ 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_MON_GET_VERSION_REPLY:
+ handle_get_version_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_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_GET_VERSION_REPLY:
+ if (le64_to_cpu(hdr->tid) != 0)
+ return get_generic_reply(con, hdr, skip);
+
+ /*
+ * Older OSDs don't set reply tid even if the orignal
+ * request had a non-zero tid. Workaround this weirdness
+ * by falling through to the allocate case.
+ */
+ case CEPH_MSG_MON_MAP:
+ case CEPH_MSG_MDS_MAP:
+ case CEPH_MSG_OSD_MAP:
+ m = ceph_msg_new(type, front_len, GFP_NOFS, false);
+ if (!m)
+ return NULL; /* ENOMEM--return skip == 0 */
+ break;
+ }
+
+ if (!m) {
+ pr_info("alloc_msg unknown type %d\n", type);
+ *skip = 1;
+ } else if (front_len > m->front_alloc_len) {
+ pr_warn("mon_alloc_msg front %d > prealloc %d (%u#%llu)\n",
+ front_len, m->front_alloc_len,
+ (unsigned int)con->peer_name.type,
+ le64_to_cpu(con->peer_name.num));
+ ceph_msg_put(m);
+ m = ceph_msg_new(type, front_len, GFP_NOFS, false);
+ }
+
+ 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->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);
+}
+
+/*
+ * We can ignore refcounting on the connection struct, as all references
+ * will come from the messenger workqueue, which is drained prior to
+ * mon_client destruction.
+ */
+static struct ceph_connection *con_get(struct ceph_connection *con)
+{
+ return con;
+}
+
+static void con_put(struct ceph_connection *con)
+{
+}
+
+static const struct ceph_connection_operations mon_con_ops = {
+ .get = con_get,
+ .put = con_put,
+ .dispatch = dispatch,
+ .fault = mon_fault,
+ .alloc_msg = mon_alloc_msg,
+};