fs/ceph/mon_client.c

   1 #include "ceph_debug.h"
   2
   3 #include <linux/types.h>
   4 #include <linux/random.h>
   5 #include <linux/sched.h>
   6
   7 #include "mon_client.h"
   8 #include "super.h"
   9 #include "auth.h"
  10 #include "decode.h"
  11
  12 /*
  13  * Interact with Ceph monitor cluster.  Handle requests for new map
  14  * versions, and periodically resend as needed.  Also implement
  15  * statfs() and umount().
  16  *
  17  * A small cluster of Ceph "monitors" are responsible for managing critical
  18  * cluster configuration and state information.  An odd number (e.g., 3, 5)
  19  * of cmon daemons use a modified version of the Paxos part-time parliament
  20  * algorithm to manage the MDS map (mds cluster membership), OSD map, and
  21  * list of clients who have mounted the file system.
  22  *
  23  * We maintain an open, active session with a monitor at all times in order to
  24  * receive timely MDSMap updates.  We periodically send a keepalive byte on the
  25  * TCP socket to ensure we detect a failure.  If the connection does break, we
  26  * randomly hunt for a new monitor.  Once the connection is reestablished, we
  27  * resend any outstanding requests.
  28  */
  29
  30 const static struct ceph_connection_operations mon_con_ops;
  31
  32 /*
  33  * Decode a monmap blob (e.g., during mount).
  34  */
  35 struct ceph_monmap *ceph_monmap_decode(void *p, void *end)
  36 {
  37         struct ceph_monmap *m = NULL;
  38         int i, err = -EINVAL;
  39         struct ceph_fsid fsid;
  40         u32 epoch, num_mon;
  41         u16 version;
  42         u32 len;
  43
  44         ceph_decode_32_safe(&p, end, len, bad);
  45         ceph_decode_need(&p, end, len, bad);
  46
  47         dout("monmap_decode %p %p len %d\n", p, end, (int)(end-p));
  48
  49         ceph_decode_16_safe(&p, end, version, bad);
  50
  51         ceph_decode_need(&p, end, sizeof(fsid) + 2*sizeof(u32), bad);
  52         ceph_decode_copy(&p, &fsid, sizeof(fsid));
  53         epoch = ceph_decode_32(&p);
  54
  55         num_mon = ceph_decode_32(&p);
  56         ceph_decode_need(&p, end, num_mon*sizeof(m->mon_inst[0]), bad);
  57
  58         if (num_mon >= CEPH_MAX_MON)
  59                 goto bad;
  60         m = kmalloc(sizeof(*m) + sizeof(m->mon_inst[0])*num_mon, GFP_NOFS);
  61         if (m == NULL)
  62                 return ERR_PTR(-ENOMEM);
  63         m->fsid = fsid;
  64         m->epoch = epoch;
  65         m->num_mon = num_mon;
  66         ceph_decode_copy(&p, m->mon_inst, num_mon*sizeof(m->mon_inst[0]));
  67         for (i = 0; i < num_mon; i++)
  68                 ceph_decode_addr(&m->mon_inst[i].addr);
  69
  70         dout("monmap_decode epoch %d, num_mon %d\n", m->epoch,
  71              m->num_mon);
  72         for (i = 0; i < m->num_mon; i++)
  73                 dout("monmap_decode  mon%d is %s\n", i,
  74                      pr_addr(&m->mon_inst[i].addr.in_addr));
  75         return m;
  76
  77 bad:
  78         dout("monmap_decode failed with %d\n", err);
  79         kfree(m);
  80         return ERR_PTR(err);
  81 }
  82
  83 /*
  84  * return true if *addr is included in the monmap.
  85  */
  86 int ceph_monmap_contains(struct ceph_monmap *m, struct ceph_entity_addr *addr)
  87 {
  88         int i;
  89
  90         for (i = 0; i < m->num_mon; i++)
  91                 if (ceph_entity_addr_equal(addr, &m->mon_inst[i].addr))
  92                         return 1;
  93         return 0;
  94 }
  95
  96 /*
  97  * Close monitor session, if any.
  98  */
  99 static void __close_session(struct ceph_mon_client *monc)
 100 {
 101         if (monc->con) {
 102                 dout("__close_session closing mon%d\n", monc->cur_mon);
 103                 ceph_con_revoke(monc->con, monc->m_auth);
 104                 ceph_con_close(monc->con);
 105                 monc->cur_mon = -1;
 106                 ceph_auth_reset(monc->auth);
 107         }
 108 }
 109
 110 /*
 111  * Open a session with a (new) monitor.
 112  */
 113 static int __open_session(struct ceph_mon_client *monc)
 114 {
 115         char r;
 116         int ret;
 117
 118         if (monc->cur_mon < 0) {
 119                 get_random_bytes(&r, 1);
 120                 monc->cur_mon = r % monc->monmap->num_mon;
 121                 dout("open_session num=%d r=%d -> mon%d\n",
 122                      monc->monmap->num_mon, r, monc->cur_mon);
 123                 monc->sub_sent = 0;
 124                 monc->sub_renew_after = jiffies;  /* i.e., expired */
 125                 monc->want_next_osdmap = !!monc->want_next_osdmap;
 126
 127                 dout("open_session mon%d opening\n", monc->cur_mon);
 128                 monc->con->peer_name.type = CEPH_ENTITY_TYPE_MON;
 129                 monc->con->peer_name.num = cpu_to_le64(monc->cur_mon);
 130                 ceph_con_open(monc->con,
 131                               &monc->monmap->mon_inst[monc->cur_mon].addr);
 132
 133                 /* initiatiate authentication handshake */
 134                 ret = ceph_auth_build_hello(monc->auth,
 135                                             monc->m_auth->front.iov_base,
 136                                             monc->m_auth->front_max);
 137                 monc->m_auth->front.iov_len = ret;
 138                 monc->m_auth->hdr.front_len = cpu_to_le32(ret);
 139                 ceph_msg_get(monc->m_auth);  /* keep our ref */
 140                 ceph_con_send(monc->con, monc->m_auth);
 141         } else {
 142                 dout("open_session mon%d already open\n", monc->cur_mon);
 143         }
 144         return 0;
 145 }
 146
 147 static bool __sub_expired(struct ceph_mon_client *monc)
 148 {
 149         return time_after_eq(jiffies, monc->sub_renew_after);
 150 }
 151
 152 /*
 153  * Reschedule delayed work timer.
 154  */
 155 static void __schedule_delayed(struct ceph_mon_client *monc)
 156 {
 157         unsigned delay;
 158
 159         if (monc->cur_mon < 0 || __sub_expired(monc))
 160                 delay = 10 * HZ;
 161         else
 162                 delay = 20 * HZ;
 163         dout("__schedule_delayed after %u\n", delay);
 164         schedule_delayed_work(&monc->delayed_work, delay);
 165 }
 166
 167 /*
 168  * Send subscribe request for mdsmap and/or osdmap.
 169  */
 170 static void __send_subscribe(struct ceph_mon_client *monc)
 171 {
 172         dout("__send_subscribe sub_sent=%u exp=%u want_osd=%d\n",
 173              (unsigned)monc->sub_sent, __sub_expired(monc),
 174              monc->want_next_osdmap);
 175         if ((__sub_expired(monc) && !monc->sub_sent) ||
 176             monc->want_next_osdmap == 1) {
 177                 struct ceph_msg *msg;
 178                 struct ceph_mon_subscribe_item *i;
 179                 void *p, *end;
 180
 181                 msg = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 96, 0, 0, NULL);
 182                 if (!msg)
 183                         return;
 184
 185                 p = msg->front.iov_base;
 186                 end = p + msg->front.iov_len;
 187
 188                 dout("__send_subscribe to 'mdsmap' %u+\n",
 189                      (unsigned)monc->have_mdsmap);
 190                 if (monc->want_next_osdmap) {
 191                         dout("__send_subscribe to 'osdmap' %u\n",
 192                              (unsigned)monc->have_osdmap);
 193                         ceph_encode_32(&p, 3);
 194                         ceph_encode_string(&p, end, "osdmap", 6);
 195                         i = p;
 196                         i->have = cpu_to_le64(monc->have_osdmap);
 197                         i->onetime = 1;
 198                         p += sizeof(*i);
 199                         monc->want_next_osdmap = 2;  /* requested */
 200                 } else {
 201                         ceph_encode_32(&p, 2);
 202                 }
 203                 ceph_encode_string(&p, end, "mdsmap", 6);
 204                 i = p;
 205                 i->have = cpu_to_le64(monc->have_mdsmap);
 206                 i->onetime = 0;
 207                 p += sizeof(*i);
 208                 ceph_encode_string(&p, end, "monmap", 6);
 209                 i = p;
 210                 i->have = 0;
 211                 i->onetime = 0;
 212                 p += sizeof(*i);
 213
 214                 msg->front.iov_len = p - msg->front.iov_base;
 215                 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
 216                 ceph_con_send(monc->con, msg);
 217
 218                 monc->sub_sent = jiffies | 1;  /* never 0 */
 219         }
 220 }
 221
 222 static void handle_subscribe_ack(struct ceph_mon_client *monc,
 223                                  struct ceph_msg *msg)
 224 {
 225         unsigned seconds;
 226         struct ceph_mon_subscribe_ack *h = msg->front.iov_base;
 227
 228         if (msg->front.iov_len < sizeof(*h))
 229                 goto bad;
 230         seconds = le32_to_cpu(h->duration);
 231
 232         mutex_lock(&monc->mutex);
 233         if (monc->hunting) {
 234                 pr_info("mon%d %s session established\n",
 235                         monc->cur_mon, pr_addr(&monc->con->peer_addr.in_addr));
 236                 monc->hunting = false;
 237         }
 238         dout("handle_subscribe_ack after %d seconds\n", seconds);
 239         monc->sub_renew_after = monc->sub_sent + (seconds >> 1)*HZ - 1;
 240         monc->sub_sent = 0;
 241         mutex_unlock(&monc->mutex);
 242         return;
 243 bad:
 244         pr_err("got corrupt subscribe-ack msg\n");
 245         ceph_msg_dump(msg);
 246 }
 247
 248 /*
 249  * Keep track of which maps we have
 250  */
 251 int ceph_monc_got_mdsmap(struct ceph_mon_client *monc, u32 got)
 252 {
 253         mutex_lock(&monc->mutex);
 254         monc->have_mdsmap = got;
 255         mutex_unlock(&monc->mutex);
 256         return 0;
 257 }
 258
 259 int ceph_monc_got_osdmap(struct ceph_mon_client *monc, u32 got)
 260 {
 261         mutex_lock(&monc->mutex);
 262         monc->have_osdmap = got;
 263         monc->want_next_osdmap = 0;
 264         mutex_unlock(&monc->mutex);
 265         return 0;
 266 }
 267
 268 /*
 269  * Register interest in the next osdmap
 270  */
 271 void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc)
 272 {
 273         dout("request_next_osdmap have %u\n", monc->have_osdmap);
 274         mutex_lock(&monc->mutex);
 275         if (!monc->want_next_osdmap)
 276                 monc->want_next_osdmap = 1;
 277         if (monc->want_next_osdmap < 2)
 278                 __send_subscribe(monc);
 279         mutex_unlock(&monc->mutex);
 280 }
 281
 282 /*
 283  *
 284  */
 285 int ceph_monc_open_session(struct ceph_mon_client *monc)
 286 {
 287         if (!monc->con) {
 288                 monc->con = kmalloc(sizeof(*monc->con), GFP_KERNEL);
 289                 if (!monc->con)
 290                         return -ENOMEM;
 291                 ceph_con_init(monc->client->msgr, monc->con);
 292                 monc->con->private = monc;
 293                 monc->con->ops = &mon_con_ops;
 294         }
 295
 296         mutex_lock(&monc->mutex);
 297         __open_session(monc);
 298         __schedule_delayed(monc);
 299         mutex_unlock(&monc->mutex);
 300         return 0;
 301 }
 302
 303 /*
 304  * The monitor responds with mount ack indicate mount success.  The
 305  * included client ticket allows the client to talk to MDSs and OSDs.
 306  */
 307 static void ceph_monc_handle_map(struct ceph_mon_client *monc,
 308                                  struct ceph_msg *msg)
 309 {
 310         struct ceph_client *client = monc->client;
 311         struct ceph_monmap *monmap = NULL, *old = monc->monmap;
 312         void *p, *end;
 313
 314         mutex_lock(&monc->mutex);
 315
 316         dout("handle_monmap\n");
 317         p = msg->front.iov_base;
 318         end = p + msg->front.iov_len;
 319
 320         monmap = ceph_monmap_decode(p, end);
 321         if (IS_ERR(monmap)) {
 322                 pr_err("problem decoding monmap, %d\n",
 323                        (int)PTR_ERR(monmap));
 324                 goto out;
 325         }
 326
 327         if (ceph_check_fsid(monc->client, &monmap->fsid) < 0) {
 328                 kfree(monmap);
 329                 goto out;
 330         }
 331
 332         client->monc.monmap = monmap;
 333         kfree(old);
 334
 335 out:
 336         mutex_unlock(&monc->mutex);
 337         wake_up(&client->mount_wq);
 338 }
 339
 340 /*
 341  * statfs
 342  */
 343 static void handle_statfs_reply(struct ceph_mon_client *monc,
 344                                 struct ceph_msg *msg)
 345 {
 346         struct ceph_mon_statfs_request *req;
 347         struct ceph_mon_statfs_reply *reply = msg->front.iov_base;
 348         u64 tid;
 349
 350         if (msg->front.iov_len != sizeof(*reply))
 351                 goto bad;
 352         tid = le64_to_cpu(msg->hdr.tid);
 353         dout("handle_statfs_reply %p tid %llu\n", msg, tid);
 354
 355         mutex_lock(&monc->mutex);
 356         req = radix_tree_lookup(&monc->statfs_request_tree, tid);
 357         if (req) {
 358                 *req->buf = reply->st;
 359                 req->result = 0;
 360         }
 361         mutex_unlock(&monc->mutex);
 362         if (req)
 363                 complete(&req->completion);
 364         return;
 365
 366 bad:
 367         pr_err("corrupt statfs reply, no tid\n");
 368         ceph_msg_dump(msg);
 369 }
 370
 371 /*
 372  * (re)send a statfs request
 373  */
 374 static int send_statfs(struct ceph_mon_client *monc,
 375                        struct ceph_mon_statfs_request *req)
 376 {
 377         struct ceph_msg *msg;
 378         struct ceph_mon_statfs *h;
 379
 380         dout("send_statfs tid %llu\n", req->tid);
 381         msg = ceph_msg_new(CEPH_MSG_STATFS, sizeof(*h), 0, 0, NULL);
 382         if (IS_ERR(msg))
 383                 return PTR_ERR(msg);
 384         req->request = msg;
 385         msg->hdr.tid = cpu_to_le64(req->tid);
 386         h = msg->front.iov_base;
 387         h->monhdr.have_version = 0;
 388         h->monhdr.session_mon = cpu_to_le16(-1);
 389         h->monhdr.session_mon_tid = 0;
 390         h->fsid = monc->monmap->fsid;
 391         ceph_con_send(monc->con, msg);
 392         return 0;
 393 }
 394
 395 /*
 396  * Do a synchronous statfs().
 397  */
 398 int ceph_monc_do_statfs(struct ceph_mon_client *monc, struct ceph_statfs *buf)
 399 {
 400         struct ceph_mon_statfs_request req;
 401         int err;
 402
 403         req.buf = buf;
 404         init_completion(&req.completion);
 405
 406         /* allocate memory for reply */
 407         err = ceph_msgpool_resv(&monc->msgpool_statfs_reply, 1);
 408         if (err)
 409                 return err;
 410
 411         /* register request */
 412         mutex_lock(&monc->mutex);
 413         req.tid = ++monc->last_tid;
 414         req.last_attempt = jiffies;
 415         req.delay = BASE_DELAY_INTERVAL;
 416         if (radix_tree_insert(&monc->statfs_request_tree, req.tid, &req) < 0) {
 417                 mutex_unlock(&monc->mutex);
 418                 pr_err("ENOMEM in do_statfs\n");
 419                 return -ENOMEM;
 420         }
 421         monc->num_statfs_requests++;
 422         mutex_unlock(&monc->mutex);
 423
 424         /* send request and wait */
 425         err = send_statfs(monc, &req);
 426         if (!err)
 427                 err = wait_for_completion_interruptible(&req.completion);
 428
 429         mutex_lock(&monc->mutex);
 430         radix_tree_delete(&monc->statfs_request_tree, req.tid);
 431         monc->num_statfs_requests--;
 432         ceph_msgpool_resv(&monc->msgpool_statfs_reply, -1);
 433         mutex_unlock(&monc->mutex);
 434
 435         if (!err)
 436                 err = req.result;
 437         return err;
 438 }
 439
 440 /*
 441  * Resend pending statfs requests.
 442  */
 443 static void __resend_statfs(struct ceph_mon_client *monc)
 444 {
 445         u64 next_tid = 0;
 446         int got;
 447         int did = 0;
 448         struct ceph_mon_statfs_request *req;
 449
 450         while (1) {
 451                 got = radix_tree_gang_lookup(&monc->statfs_request_tree,
 452                                              (void **)&req,
 453                                              next_tid, 1);
 454                 if (got == 0)
 455                         break;
 456                 did++;
 457                 next_tid = req->tid + 1;
 458
 459                 send_statfs(monc, req);
 460         }
 461 }
 462
 463 /*
 464  * Delayed work.  If we haven't mounted yet, retry.  Otherwise,
 465  * renew/retry subscription as needed (in case it is timing out, or we
 466  * got an ENOMEM).  And keep the monitor connection alive.
 467  */
 468 static void delayed_work(struct work_struct *work)
 469 {
 470         struct ceph_mon_client *monc =
 471                 container_of(work, struct ceph_mon_client, delayed_work.work);
 472
 473         dout("monc delayed_work\n");
 474         mutex_lock(&monc->mutex);
 475         if (monc->hunting) {
 476                 __close_session(monc);
 477                 __open_session(monc);  /* continue hunting */
 478         } else {
 479                 ceph_con_keepalive(monc->con);
 480                 if (monc->auth->ops->is_authenticated(monc->auth))
 481                         __send_subscribe(monc);
 482         }
 483         __schedule_delayed(monc);
 484         mutex_unlock(&monc->mutex);
 485 }
 486
 487 /*
 488  * On startup, we build a temporary monmap populated with the IPs
 489  * provided by mount(2).
 490  */
 491 static int build_initial_monmap(struct ceph_mon_client *monc)
 492 {
 493         struct ceph_mount_args *args = monc->client->mount_args;
 494         struct ceph_entity_addr *mon_addr = args->mon_addr;
 495         int num_mon = args->num_mon;
 496         int i;
 497
 498         /* build initial monmap */
 499         monc->monmap = kzalloc(sizeof(*monc->monmap) +
 500                                num_mon*sizeof(monc->monmap->mon_inst[0]),
 501                                GFP_KERNEL);
 502         if (!monc->monmap)
 503                 return -ENOMEM;
 504         for (i = 0; i < num_mon; i++) {
 505                 monc->monmap->mon_inst[i].addr = mon_addr[i];
 506                 monc->monmap->mon_inst[i].addr.erank = 0;
 507                 monc->monmap->mon_inst[i].addr.nonce = 0;
 508                 monc->monmap->mon_inst[i].name.type =
 509                         CEPH_ENTITY_TYPE_MON;
 510                 monc->monmap->mon_inst[i].name.num = cpu_to_le64(i);
 511         }
 512         monc->monmap->num_mon = num_mon;
 513         monc->have_fsid = false;
 514
 515         /* release addr memory */
 516         kfree(args->mon_addr);
 517         args->mon_addr = NULL;
 518         args->num_mon = 0;
 519         return 0;
 520 }
 521
 522 int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
 523 {
 524         int err = 0;
 525
 526         dout("init\n");
 527         memset(monc, 0, sizeof(*monc));
 528         monc->client = cl;
 529         monc->monmap = NULL;
 530         mutex_init(&monc->mutex);
 531
 532         err = build_initial_monmap(monc);
 533         if (err)
 534                 goto out;
 535
 536         monc->con = NULL;
 537
 538         /* authentication */
 539         monc->auth = ceph_auth_init(cl->mount_args->name,
 540                                     cl->mount_args->secret);
 541         if (IS_ERR(monc->auth))
 542                 return PTR_ERR(monc->auth);
 543         monc->auth->want_keys =
 544                 CEPH_ENTITY_TYPE_AUTH | CEPH_ENTITY_TYPE_MON |
 545                 CEPH_ENTITY_TYPE_OSD | CEPH_ENTITY_TYPE_MDS;
 546
 547         /* msg pools */
 548         err = ceph_msgpool_init(&monc->msgpool_subscribe_ack,
 549                                sizeof(struct ceph_mon_subscribe_ack), 1, false);
 550         if (err < 0)
 551                 goto out_monmap;
 552         err = ceph_msgpool_init(&monc->msgpool_statfs_reply,
 553                                 sizeof(struct ceph_mon_statfs_reply), 0, false);
 554         if (err < 0)
 555                 goto out_pool1;
 556         err = ceph_msgpool_init(&monc->msgpool_auth_reply, 4096, 1, false);
 557         if (err < 0)
 558                 goto out_pool2;
 559
 560         monc->m_auth = ceph_msg_new(CEPH_MSG_AUTH, 4096, 0, 0, NULL);
 561         if (IS_ERR(monc->m_auth)) {
 562                 err = PTR_ERR(monc->m_auth);
 563                 monc->m_auth = NULL;
 564                 goto out_pool3;
 565         }
 566
 567         monc->cur_mon = -1;
 568         monc->hunting = true;
 569         monc->sub_renew_after = jiffies;
 570         monc->sub_sent = 0;
 571
 572         INIT_DELAYED_WORK(&monc->delayed_work, delayed_work);
 573         INIT_RADIX_TREE(&monc->statfs_request_tree, GFP_NOFS);
 574         monc->num_statfs_requests = 0;
 575         monc->last_tid = 0;
 576
 577         monc->have_mdsmap = 0;
 578         monc->have_osdmap = 0;
 579         monc->want_next_osdmap = 1;
 580         return 0;
 581
 582 out_pool3:
 583         ceph_msgpool_destroy(&monc->msgpool_auth_reply);
 584 out_pool2:
 585         ceph_msgpool_destroy(&monc->msgpool_subscribe_ack);
 586 out_pool1:
 587         ceph_msgpool_destroy(&monc->msgpool_statfs_reply);
 588 out_monmap:
 589         kfree(monc->monmap);
 590 out:
 591         return err;
 592 }
 593
 594 void ceph_monc_stop(struct ceph_mon_client *monc)
 595 {
 596         dout("stop\n");
 597         cancel_delayed_work_sync(&monc->delayed_work);
 598
 599         mutex_lock(&monc->mutex);
 600         __close_session(monc);
 601         if (monc->con) {
 602                 monc->con->private = NULL;
 603                 monc->con->ops->put(monc->con);
 604                 monc->con = NULL;
 605         }
 606         mutex_unlock(&monc->mutex);
 607
 608         ceph_auth_destroy(monc->auth);
 609
 610         ceph_msg_put(monc->m_auth);
 611         ceph_msgpool_destroy(&monc->msgpool_subscribe_ack);
 612         ceph_msgpool_destroy(&monc->msgpool_statfs_reply);
 613         ceph_msgpool_destroy(&monc->msgpool_auth_reply);
 614
 615         kfree(monc->monmap);
 616 }
 617
 618
 619 static void handle_auth_reply(struct ceph_mon_client *monc,
 620                               struct ceph_msg *msg)
 621 {
 622         int ret;
 623
 624         mutex_lock(&monc->mutex);
 625         ret = ceph_handle_auth_reply(monc->auth, msg->front.iov_base,
 626                                      msg->front.iov_len,
 627                                      monc->m_auth->front.iov_base,
 628                                      monc->m_auth->front_max);
 629         if (ret < 0) {
 630                 monc->client->mount_err = ret;
 631                 wake_up(&monc->client->mount_wq);
 632         } else if (ret > 0) {
 633                 monc->m_auth->front.iov_len = ret;
 634                 monc->m_auth->hdr.front_len = cpu_to_le32(ret);
 635                 ceph_msg_get(monc->m_auth);  /* keep our ref */
 636                 ceph_con_send(monc->con, monc->m_auth);
 637         } else if (monc->auth->ops->is_authenticated(monc->auth)) {
 638                 dout("authenticated, starting session\n");
 639
 640                 monc->client->msgr->inst.name.type = CEPH_ENTITY_TYPE_CLIENT;
 641                 monc->client->msgr->inst.name.num = monc->auth->global_id;
 642
 643                 __send_subscribe(monc);
 644                 __resend_statfs(monc);
 645         }
 646         mutex_unlock(&monc->mutex);
 647 }
 648
 649 /*
 650  * handle incoming message
 651  */
 652 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
 653 {
 654         struct ceph_mon_client *monc = con->private;
 655         int type = le16_to_cpu(msg->hdr.type);
 656
 657         if (!monc)
 658                 return;
 659
 660         switch (type) {
 661         case CEPH_MSG_AUTH_REPLY:
 662                 handle_auth_reply(monc, msg);
 663                 break;
 664
 665         case CEPH_MSG_MON_SUBSCRIBE_ACK:
 666                 handle_subscribe_ack(monc, msg);
 667                 break;
 668
 669         case CEPH_MSG_STATFS_REPLY:
 670                 handle_statfs_reply(monc, msg);
 671                 break;
 672
 673         case CEPH_MSG_MON_MAP:
 674                 ceph_monc_handle_map(monc, msg);
 675                 break;
 676
 677         case CEPH_MSG_MDS_MAP:
 678                 ceph_mdsc_handle_map(&monc->client->mdsc, msg);
 679                 break;
 680
 681         case CEPH_MSG_OSD_MAP:
 682                 ceph_osdc_handle_map(&monc->client->osdc, msg);
 683                 break;
 684
 685         default:
 686                 pr_err("received unknown message type %d %s\n", type,
 687                        ceph_msg_type_name(type));
 688         }
 689         ceph_msg_put(msg);
 690 }
 691
 692 /*
 693  * Allocate memory for incoming message
 694  */
 695 static struct ceph_msg *mon_alloc_msg(struct ceph_connection *con,
 696                                       struct ceph_msg_header *hdr)
 697 {
 698         struct ceph_mon_client *monc = con->private;
 699         int type = le16_to_cpu(hdr->type);
 700         int front = le32_to_cpu(hdr->front_len);
 701
 702         switch (type) {
 703         case CEPH_MSG_MON_SUBSCRIBE_ACK:
 704                 return ceph_msgpool_get(&monc->msgpool_subscribe_ack, front);
 705         case CEPH_MSG_STATFS_REPLY:
 706                 return ceph_msgpool_get(&monc->msgpool_statfs_reply, front);
 707         case CEPH_MSG_AUTH_REPLY:
 708                 return ceph_msgpool_get(&monc->msgpool_auth_reply, front);
 709         }
 710         return ceph_alloc_msg(con, hdr);
 711 }
 712
 713 /*
 714  * If the monitor connection resets, pick a new monitor and resubmit
 715  * any pending requests.
 716  */
 717 static void mon_fault(struct ceph_connection *con)
 718 {
 719         struct ceph_mon_client *monc = con->private;
 720
 721         if (!monc)
 722                 return;
 723
 724         dout("mon_fault\n");
 725         mutex_lock(&monc->mutex);
 726         if (!con->private)
 727                 goto out;
 728
 729         if (monc->con && !monc->hunting)
 730                 pr_info("mon%d %s session lost, "
 731                         "hunting for new mon\n", monc->cur_mon,
 732                         pr_addr(&monc->con->peer_addr.in_addr));
 733
 734         __close_session(monc);
 735         if (!monc->hunting) {
 736                 /* start hunting */
 737                 monc->hunting = true;
 738                 __open_session(monc);
 739         } else {
 740                 /* already hunting, let's wait a bit */
 741                 __schedule_delayed(monc);
 742         }
 743 out:
 744         mutex_unlock(&monc->mutex);
 745 }
 746
 747 const static struct ceph_connection_operations mon_con_ops = {
 748         .get = ceph_con_get,
 749         .put = ceph_con_put,
 750         .dispatch = dispatch,
 751         .fault = mon_fault,
 752         .alloc_msg = mon_alloc_msg,
 753         .alloc_middle = ceph_alloc_middle,
 754 };