net/ceph/mon_client.c

   1 #include <linux/ceph/ceph_debug.h>
   2
   3 #include <linux/module.h>
   4 #include <linux/types.h>
   5 #include <linux/slab.h>
   6 #include <linux/random.h>
   7 #include <linux/sched.h>
   8
   9 #include <linux/ceph/mon_client.h>
  10 #include <linux/ceph/libceph.h>
  11 #include <linux/ceph/decode.h>
  12
  13 #include <linux/ceph/auth.h>
  14
  15 /*
  16  * Interact with Ceph monitor cluster.  Handle requests for new map
  17  * versions, and periodically resend as needed.  Also implement
  18  * statfs() and umount().
  19  *
  20  * A small cluster of Ceph "monitors" are responsible for managing critical
  21  * cluster configuration and state information.  An odd number (e.g., 3, 5)
  22  * of cmon daemons use a modified version of the Paxos part-time parliament
  23  * algorithm to manage the MDS map (mds cluster membership), OSD map, and
  24  * list of clients who have mounted the file system.
  25  *
  26  * We maintain an open, active session with a monitor at all times in order to
  27  * receive timely MDSMap updates.  We periodically send a keepalive byte on the
  28  * TCP socket to ensure we detect a failure.  If the connection does break, we
  29  * randomly hunt for a new monitor.  Once the connection is reestablished, we
  30  * resend any outstanding requests.
  31  */
  32
  33 static const struct ceph_connection_operations mon_con_ops;
  34
  35 static int __validate_auth(struct ceph_mon_client *monc);
  36
  37 /*
  38  * Decode a monmap blob (e.g., during mount).
  39  */
  40 struct ceph_monmap *ceph_monmap_decode(void *p, void *end)
  41 {
  42         struct ceph_monmap *m = NULL;
  43         int i, err = -EINVAL;
  44         struct ceph_fsid fsid;
  45         u32 epoch, num_mon;
  46         u16 version;
  47         u32 len;
  48
  49         ceph_decode_32_safe(&p, end, len, bad);
  50         ceph_decode_need(&p, end, len, bad);
  51
  52         dout("monmap_decode %p %p len %d\n", p, end, (int)(end-p));
  53
  54         ceph_decode_16_safe(&p, end, version, bad);
  55
  56         ceph_decode_need(&p, end, sizeof(fsid) + 2*sizeof(u32), bad);
  57         ceph_decode_copy(&p, &fsid, sizeof(fsid));
  58         epoch = ceph_decode_32(&p);
  59
  60         num_mon = ceph_decode_32(&p);
  61         ceph_decode_need(&p, end, num_mon*sizeof(m->mon_inst[0]), bad);
  62
  63         if (num_mon >= CEPH_MAX_MON)
  64                 goto bad;
  65         m = kmalloc(sizeof(*m) + sizeof(m->mon_inst[0])*num_mon, GFP_NOFS);
  66         if (m == NULL)
  67                 return ERR_PTR(-ENOMEM);
  68         m->fsid = fsid;
  69         m->epoch = epoch;
  70         m->num_mon = num_mon;
  71         ceph_decode_copy(&p, m->mon_inst, num_mon*sizeof(m->mon_inst[0]));
  72         for (i = 0; i < num_mon; i++)
  73                 ceph_decode_addr(&m->mon_inst[i].addr);
  74
  75         dout("monmap_decode epoch %d, num_mon %d\n", m->epoch,
  76              m->num_mon);
  77         for (i = 0; i < m->num_mon; i++)
  78                 dout("monmap_decode  mon%d is %s\n", i,
  79                      ceph_pr_addr(&m->mon_inst[i].addr.in_addr));
  80         return m;
  81
  82 bad:
  83         dout("monmap_decode failed with %d\n", err);
  84         kfree(m);
  85         return ERR_PTR(err);
  86 }
  87
  88 /*
  89  * return true if *addr is included in the monmap.
  90  */
  91 int ceph_monmap_contains(struct ceph_monmap *m, struct ceph_entity_addr *addr)
  92 {
  93         int i;
  94
  95         for (i = 0; i < m->num_mon; i++)
  96                 if (memcmp(addr, &m->mon_inst[i].addr, sizeof(*addr)) == 0)
  97                         return 1;
  98         return 0;
  99 }
 100
 101 /*
 102  * Send an auth request.
 103  */
 104 static void __send_prepared_auth_request(struct ceph_mon_client *monc, int len)
 105 {
 106         monc->pending_auth = 1;
 107         monc->m_auth->front.iov_len = len;
 108         monc->m_auth->hdr.front_len = cpu_to_le32(len);
 109         ceph_con_revoke(monc->con, monc->m_auth);
 110         ceph_msg_get(monc->m_auth);  /* keep our ref */
 111         ceph_con_send(monc->con, monc->m_auth);
 112 }
 113
 114 /*
 115  * Close monitor session, if any.
 116  */
 117 static void __close_session(struct ceph_mon_client *monc)
 118 {
 119         if (monc->con) {
 120                 dout("__close_session closing mon%d\n", monc->cur_mon);
 121                 ceph_con_revoke(monc->con, monc->m_auth);
 122                 ceph_con_close(monc->con);
 123                 monc->cur_mon = -1;
 124                 monc->pending_auth = 0;
 125                 ceph_auth_reset(monc->auth);
 126         }
 127 }
 128
 129 /*
 130  * Open a session with a (new) monitor.
 131  */
 132 static int __open_session(struct ceph_mon_client *monc)
 133 {
 134         char r;
 135         int ret;
 136
 137         if (monc->cur_mon < 0) {
 138                 get_random_bytes(&r, 1);
 139                 monc->cur_mon = r % monc->monmap->num_mon;
 140                 dout("open_session num=%d r=%d -> mon%d\n",
 141                      monc->monmap->num_mon, r, monc->cur_mon);
 142                 monc->sub_sent = 0;
 143                 monc->sub_renew_after = jiffies;  /* i.e., expired */
 144                 monc->want_next_osdmap = !!monc->want_next_osdmap;
 145
 146                 dout("open_session mon%d opening\n", monc->cur_mon);
 147                 monc->con->peer_name.type = CEPH_ENTITY_TYPE_MON;
 148                 monc->con->peer_name.num = cpu_to_le64(monc->cur_mon);
 149                 ceph_con_open(monc->con,
 150                               &monc->monmap->mon_inst[monc->cur_mon].addr);
 151
 152                 /* initiatiate authentication handshake */
 153                 ret = ceph_auth_build_hello(monc->auth,
 154                                             monc->m_auth->front.iov_base,
 155                                             monc->m_auth->front_max);
 156                 __send_prepared_auth_request(monc, ret);
 157         } else {
 158                 dout("open_session mon%d already open\n", monc->cur_mon);
 159         }
 160         return 0;
 161 }
 162
 163 static bool __sub_expired(struct ceph_mon_client *monc)
 164 {
 165         return time_after_eq(jiffies, monc->sub_renew_after);
 166 }
 167
 168 /*
 169  * Reschedule delayed work timer.
 170  */
 171 static void __schedule_delayed(struct ceph_mon_client *monc)
 172 {
 173         unsigned delay;
 174
 175         if (monc->cur_mon < 0 || __sub_expired(monc))
 176                 delay = 10 * HZ;
 177         else
 178                 delay = 20 * HZ;
 179         dout("__schedule_delayed after %u\n", delay);
 180         schedule_delayed_work(&monc->delayed_work, delay);
 181 }
 182
 183 /*
 184  * Send subscribe request for mdsmap and/or osdmap.
 185  */
 186 static void __send_subscribe(struct ceph_mon_client *monc)
 187 {
 188         dout("__send_subscribe sub_sent=%u exp=%u want_osd=%d\n",
 189              (unsigned)monc->sub_sent, __sub_expired(monc),
 190              monc->want_next_osdmap);
 191         if ((__sub_expired(monc) && !monc->sub_sent) ||
 192             monc->want_next_osdmap == 1) {
 193                 struct ceph_msg *msg = monc->m_subscribe;
 194                 struct ceph_mon_subscribe_item *i;
 195                 void *p, *end;
 196                 int num;
 197
 198                 p = msg->front.iov_base;
 199                 end = p + msg->front_max;
 200
 201                 num = 1 + !!monc->want_next_osdmap + !!monc->want_mdsmap;
 202                 ceph_encode_32(&p, num);
 203
 204                 if (monc->want_next_osdmap) {
 205                         dout("__send_subscribe to 'osdmap' %u\n",
 206                              (unsigned)monc->have_osdmap);
 207                         ceph_encode_string(&p, end, "osdmap", 6);
 208                         i = p;
 209                         i->have = cpu_to_le64(monc->have_osdmap);
 210                         i->onetime = 1;
 211                         p += sizeof(*i);
 212                         monc->want_next_osdmap = 2;  /* requested */
 213                 }
 214                 if (monc->want_mdsmap) {
 215                         dout("__send_subscribe to 'mdsmap' %u+\n",
 216                              (unsigned)monc->have_mdsmap);
 217                         ceph_encode_string(&p, end, "mdsmap", 6);
 218                         i = p;
 219                         i->have = cpu_to_le64(monc->have_mdsmap);
 220                         i->onetime = 0;
 221                         p += sizeof(*i);
 222                 }
 223                 ceph_encode_string(&p, end, "monmap", 6);
 224                 i = p;
 225                 i->have = 0;
 226                 i->onetime = 0;
 227                 p += sizeof(*i);
 228
 229                 msg->front.iov_len = p - msg->front.iov_base;
 230                 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
 231                 ceph_con_revoke(monc->con, msg);
 232                 ceph_con_send(monc->con, ceph_msg_get(msg));
 233
 234                 monc->sub_sent = jiffies | 1;  /* never 0 */
 235         }
 236 }
 237
 238 static void handle_subscribe_ack(struct ceph_mon_client *monc,
 239                                  struct ceph_msg *msg)
 240 {
 241         unsigned seconds;
 242         struct ceph_mon_subscribe_ack *h = msg->front.iov_base;
 243
 244         if (msg->front.iov_len < sizeof(*h))
 245                 goto bad;
 246         seconds = le32_to_cpu(h->duration);
 247
 248         mutex_lock(&monc->mutex);
 249         if (monc->hunting) {
 250                 pr_info("mon%d %s session established\n",
 251                         monc->cur_mon,
 252                         ceph_pr_addr(&monc->con->peer_addr.in_addr));
 253                 monc->hunting = false;
 254         }
 255         dout("handle_subscribe_ack after %d seconds\n", seconds);
 256         monc->sub_renew_after = monc->sub_sent + (seconds >> 1)*HZ - 1;
 257         monc->sub_sent = 0;
 258         mutex_unlock(&monc->mutex);
 259         return;
 260 bad:
 261         pr_err("got corrupt subscribe-ack msg\n");
 262         ceph_msg_dump(msg);
 263 }
 264
 265 /*
 266  * Keep track of which maps we have
 267  */
 268 int ceph_monc_got_mdsmap(struct ceph_mon_client *monc, u32 got)
 269 {
 270         mutex_lock(&monc->mutex);
 271         monc->have_mdsmap = got;
 272         mutex_unlock(&monc->mutex);
 273         return 0;
 274 }
 275 EXPORT_SYMBOL(ceph_monc_got_mdsmap);
 276
 277 int ceph_monc_got_osdmap(struct ceph_mon_client *monc, u32 got)
 278 {
 279         mutex_lock(&monc->mutex);
 280         monc->have_osdmap = got;
 281         monc->want_next_osdmap = 0;
 282         mutex_unlock(&monc->mutex);
 283         return 0;
 284 }
 285
 286 /*
 287  * Register interest in the next osdmap
 288  */
 289 void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc)
 290 {
 291         dout("request_next_osdmap have %u\n", monc->have_osdmap);
 292         mutex_lock(&monc->mutex);
 293         if (!monc->want_next_osdmap)
 294                 monc->want_next_osdmap = 1;
 295         if (monc->want_next_osdmap < 2)
 296                 __send_subscribe(monc);
 297         mutex_unlock(&monc->mutex);
 298 }
 299
 300 /*
 301  *
 302  */
 303 int ceph_monc_open_session(struct ceph_mon_client *monc)
 304 {
 305         if (!monc->con) {
 306                 monc->con = kmalloc(sizeof(*monc->con), GFP_KERNEL);
 307                 if (!monc->con)
 308                         return -ENOMEM;
 309                 ceph_con_init(monc->client->msgr, monc->con);
 310                 monc->con->private = monc;
 311                 monc->con->ops = &mon_con_ops;
 312         }
 313
 314         mutex_lock(&monc->mutex);
 315         __open_session(monc);
 316         __schedule_delayed(monc);
 317         mutex_unlock(&monc->mutex);
 318         return 0;
 319 }
 320 EXPORT_SYMBOL(ceph_monc_open_session);
 321
 322 /*
 323  * The monitor responds with mount ack indicate mount success.  The
 324  * included client ticket allows the client to talk to MDSs and OSDs.
 325  */
 326 static void ceph_monc_handle_map(struct ceph_mon_client *monc,
 327                                  struct ceph_msg *msg)
 328 {
 329         struct ceph_client *client = monc->client;
 330         struct ceph_monmap *monmap = NULL, *old = monc->monmap;
 331         void *p, *end;
 332
 333         mutex_lock(&monc->mutex);
 334
 335         dout("handle_monmap\n");
 336         p = msg->front.iov_base;
 337         end = p + msg->front.iov_len;
 338
 339         monmap = ceph_monmap_decode(p, end);
 340         if (IS_ERR(monmap)) {
 341                 pr_err("problem decoding monmap, %d\n",
 342                        (int)PTR_ERR(monmap));
 343                 goto out;
 344         }
 345
 346         if (ceph_check_fsid(monc->client, &monmap->fsid) < 0) {
 347                 kfree(monmap);
 348                 goto out;
 349         }
 350
 351         client->monc.monmap = monmap;
 352         kfree(old);
 353
 354 out:
 355         mutex_unlock(&monc->mutex);
 356         wake_up_all(&client->auth_wq);
 357 }
 358
 359 /*
 360  * generic requests (e.g., statfs, poolop)
 361  */
 362 static struct ceph_mon_generic_request *__lookup_generic_req(
 363         struct ceph_mon_client *monc, u64 tid)
 364 {
 365         struct ceph_mon_generic_request *req;
 366         struct rb_node *n = monc->generic_request_tree.rb_node;
 367
 368         while (n) {
 369                 req = rb_entry(n, struct ceph_mon_generic_request, node);
 370                 if (tid < req->tid)
 371                         n = n->rb_left;
 372                 else if (tid > req->tid)
 373                         n = n->rb_right;
 374                 else
 375                         return req;
 376         }
 377         return NULL;
 378 }
 379
 380 static void __insert_generic_request(struct ceph_mon_client *monc,
 381                             struct ceph_mon_generic_request *new)
 382 {
 383         struct rb_node **p = &monc->generic_request_tree.rb_node;
 384         struct rb_node *parent = NULL;
 385         struct ceph_mon_generic_request *req = NULL;
 386
 387         while (*p) {
 388                 parent = *p;
 389                 req = rb_entry(parent, struct ceph_mon_generic_request, node);
 390                 if (new->tid < req->tid)
 391                         p = &(*p)->rb_left;
 392                 else if (new->tid > req->tid)
 393                         p = &(*p)->rb_right;
 394                 else
 395                         BUG();
 396         }
 397
 398         rb_link_node(&new->node, parent, p);
 399         rb_insert_color(&new->node, &monc->generic_request_tree);
 400 }
 401
 402 static void release_generic_request(struct kref *kref)
 403 {
 404         struct ceph_mon_generic_request *req =
 405                 container_of(kref, struct ceph_mon_generic_request, kref);
 406
 407         if (req->reply)
 408                 ceph_msg_put(req->reply);
 409         if (req->request)
 410                 ceph_msg_put(req->request);
 411
 412         kfree(req);
 413 }
 414
 415 static void put_generic_request(struct ceph_mon_generic_request *req)
 416 {
 417         kref_put(&req->kref, release_generic_request);
 418 }
 419
 420 static void get_generic_request(struct ceph_mon_generic_request *req)
 421 {
 422         kref_get(&req->kref);
 423 }
 424
 425 static struct ceph_msg *get_generic_reply(struct ceph_connection *con,
 426                                          struct ceph_msg_header *hdr,
 427                                          int *skip)
 428 {
 429         struct ceph_mon_client *monc = con->private;
 430         struct ceph_mon_generic_request *req;
 431         u64 tid = le64_to_cpu(hdr->tid);
 432         struct ceph_msg *m;
 433
 434         mutex_lock(&monc->mutex);
 435         req = __lookup_generic_req(monc, tid);
 436         if (!req) {
 437                 dout("get_generic_reply %lld dne\n", tid);
 438                 *skip = 1;
 439                 m = NULL;
 440         } else {
 441                 dout("get_generic_reply %lld got %p\n", tid, req->reply);
 442                 m = ceph_msg_get(req->reply);
 443                 /*
 444                  * we don't need to track the connection reading into
 445                  * this reply because we only have one open connection
 446                  * at a time, ever.
 447                  */
 448         }
 449         mutex_unlock(&monc->mutex);
 450         return m;
 451 }
 452
 453 static int do_generic_request(struct ceph_mon_client *monc,
 454                               struct ceph_mon_generic_request *req)
 455 {
 456         int err;
 457
 458         /* register request */
 459         mutex_lock(&monc->mutex);
 460         req->tid = ++monc->last_tid;
 461         req->request->hdr.tid = cpu_to_le64(req->tid);
 462         __insert_generic_request(monc, req);
 463         monc->num_generic_requests++;
 464         ceph_con_send(monc->con, ceph_msg_get(req->request));
 465         mutex_unlock(&monc->mutex);
 466
 467         err = wait_for_completion_interruptible(&req->completion);
 468
 469         mutex_lock(&monc->mutex);
 470         rb_erase(&req->node, &monc->generic_request_tree);
 471         monc->num_generic_requests--;
 472         mutex_unlock(&monc->mutex);
 473
 474         if (!err)
 475                 err = req->result;
 476         return err;
 477 }
 478
 479 /*
 480  * statfs
 481  */
 482 static void handle_statfs_reply(struct ceph_mon_client *monc,
 483                                 struct ceph_msg *msg)
 484 {
 485         struct ceph_mon_generic_request *req;
 486         struct ceph_mon_statfs_reply *reply = msg->front.iov_base;
 487         u64 tid = le64_to_cpu(msg->hdr.tid);
 488
 489         if (msg->front.iov_len != sizeof(*reply))
 490                 goto bad;
 491         dout("handle_statfs_reply %p tid %llu\n", msg, tid);
 492
 493         mutex_lock(&monc->mutex);
 494         req = __lookup_generic_req(monc, tid);
 495         if (req) {
 496                 *(struct ceph_statfs *)req->buf = reply->st;
 497                 req->result = 0;
 498                 get_generic_request(req);
 499         }
 500         mutex_unlock(&monc->mutex);
 501         if (req) {
 502                 complete_all(&req->completion);
 503                 put_generic_request(req);
 504         }
 505         return;
 506
 507 bad:
 508         pr_err("corrupt generic reply, tid %llu\n", tid);
 509         ceph_msg_dump(msg);
 510 }
 511
 512 /*
 513  * Do a synchronous statfs().
 514  */
 515 int ceph_monc_do_statfs(struct ceph_mon_client *monc, struct ceph_statfs *buf)
 516 {
 517         struct ceph_mon_generic_request *req;
 518         struct ceph_mon_statfs *h;
 519         int err;
 520
 521         req = kzalloc(sizeof(*req), GFP_NOFS);
 522         if (!req)
 523                 return -ENOMEM;
 524
 525         kref_init(&req->kref);
 526         req->buf = buf;
 527         req->buf_len = sizeof(*buf);
 528         init_completion(&req->completion);
 529
 530         err = -ENOMEM;
 531         req->request = ceph_msg_new(CEPH_MSG_STATFS, sizeof(*h), GFP_NOFS);
 532         if (!req->request)
 533                 goto out;
 534         req->reply = ceph_msg_new(CEPH_MSG_STATFS_REPLY, 1024, GFP_NOFS);
 535         if (!req->reply)
 536                 goto out;
 537
 538         /* fill out request */
 539         h = req->request->front.iov_base;
 540         h->monhdr.have_version = 0;
 541         h->monhdr.session_mon = cpu_to_le16(-1);
 542         h->monhdr.session_mon_tid = 0;
 543         h->fsid = monc->monmap->fsid;
 544
 545         err = do_generic_request(monc, req);
 546
 547 out:
 548         kref_put(&req->kref, release_generic_request);
 549         return err;
 550 }
 551 EXPORT_SYMBOL(ceph_monc_do_statfs);
 552
 553 /*
 554  * pool ops
 555  */
 556 static int get_poolop_reply_buf(const char *src, size_t src_len,
 557                                 char *dst, size_t dst_len)
 558 {
 559         u32 buf_len;
 560
 561         if (src_len != sizeof(u32) + dst_len)
 562                 return -EINVAL;
 563
 564         buf_len = le32_to_cpu(*(u32 *)src);
 565         if (buf_len != dst_len)
 566                 return -EINVAL;
 567
 568         memcpy(dst, src + sizeof(u32), dst_len);
 569         return 0;
 570 }
 571
 572 static void handle_poolop_reply(struct ceph_mon_client *monc,
 573                                 struct ceph_msg *msg)
 574 {
 575         struct ceph_mon_generic_request *req;
 576         struct ceph_mon_poolop_reply *reply = msg->front.iov_base;
 577         u64 tid = le64_to_cpu(msg->hdr.tid);
 578
 579         if (msg->front.iov_len < sizeof(*reply))
 580                 goto bad;
 581         dout("handle_poolop_reply %p tid %llu\n", msg, tid);
 582
 583         mutex_lock(&monc->mutex);
 584         req = __lookup_generic_req(monc, tid);
 585         if (req) {
 586                 if (req->buf_len &&
 587                     get_poolop_reply_buf(msg->front.iov_base + sizeof(*reply),
 588                                      msg->front.iov_len - sizeof(*reply),
 589                                      req->buf, req->buf_len) < 0) {
 590                         mutex_unlock(&monc->mutex);
 591                         goto bad;
 592                 }
 593                 req->result = le32_to_cpu(reply->reply_code);
 594                 get_generic_request(req);
 595         }
 596         mutex_unlock(&monc->mutex);
 597         if (req) {
 598                 complete(&req->completion);
 599                 put_generic_request(req);
 600         }
 601         return;
 602
 603 bad:
 604         pr_err("corrupt generic reply, tid %llu\n", tid);
 605         ceph_msg_dump(msg);
 606 }
 607
 608 /*
 609  * Do a synchronous pool op.
 610  */
 611 int ceph_monc_do_poolop(struct ceph_mon_client *monc, u32 op,
 612                         u32 pool, u64 snapid,
 613                         char *buf, int len)
 614 {
 615         struct ceph_mon_generic_request *req;
 616         struct ceph_mon_poolop *h;
 617         int err;
 618
 619         req = kzalloc(sizeof(*req), GFP_NOFS);
 620         if (!req)
 621                 return -ENOMEM;
 622
 623         kref_init(&req->kref);
 624         req->buf = buf;
 625         req->buf_len = len;
 626         init_completion(&req->completion);
 627
 628         err = -ENOMEM;
 629         req->request = ceph_msg_new(CEPH_MSG_POOLOP, sizeof(*h), GFP_NOFS);
 630         if (!req->request)
 631                 goto out;
 632         req->reply = ceph_msg_new(CEPH_MSG_POOLOP_REPLY, 1024, GFP_NOFS);
 633         if (!req->reply)
 634                 goto out;
 635
 636         /* fill out request */
 637         req->request->hdr.version = cpu_to_le16(2);
 638         h = req->request->front.iov_base;
 639         h->monhdr.have_version = 0;
 640         h->monhdr.session_mon = cpu_to_le16(-1);
 641         h->monhdr.session_mon_tid = 0;
 642         h->fsid = monc->monmap->fsid;
 643         h->pool = cpu_to_le32(pool);
 644         h->op = cpu_to_le32(op);
 645         h->auid = 0;
 646         h->snapid = cpu_to_le64(snapid);
 647         h->name_len = 0;
 648
 649         err = do_generic_request(monc, req);
 650
 651 out:
 652         kref_put(&req->kref, release_generic_request);
 653         return err;
 654 }
 655
 656 int ceph_monc_create_snapid(struct ceph_mon_client *monc,
 657                             u32 pool, u64 *snapid)
 658 {
 659         return ceph_monc_do_poolop(monc,  POOL_OP_CREATE_UNMANAGED_SNAP,
 660                                    pool, 0, (char *)snapid, sizeof(*snapid));
 661
 662 }
 663 EXPORT_SYMBOL(ceph_monc_create_snapid);
 664
 665 int ceph_monc_delete_snapid(struct ceph_mon_client *monc,
 666                             u32 pool, u64 snapid)
 667 {
 668         return ceph_monc_do_poolop(monc,  POOL_OP_CREATE_UNMANAGED_SNAP,
 669                                    pool, snapid, 0, 0);
 670
 671 }
 672
 673 /*
 674  * Resend pending generic requests.
 675  */
 676 static void __resend_generic_request(struct ceph_mon_client *monc)
 677 {
 678         struct ceph_mon_generic_request *req;
 679         struct rb_node *p;
 680
 681         for (p = rb_first(&monc->generic_request_tree); p; p = rb_next(p)) {
 682                 req = rb_entry(p, struct ceph_mon_generic_request, node);
 683                 ceph_con_revoke(monc->con, req->request);
 684                 ceph_con_send(monc->con, ceph_msg_get(req->request));
 685         }
 686 }
 687
 688 /*
 689  * Delayed work.  If we haven't mounted yet, retry.  Otherwise,
 690  * renew/retry subscription as needed (in case it is timing out, or we
 691  * got an ENOMEM).  And keep the monitor connection alive.
 692  */
 693 static void delayed_work(struct work_struct *work)
 694 {
 695         struct ceph_mon_client *monc =
 696                 container_of(work, struct ceph_mon_client, delayed_work.work);
 697
 698         dout("monc delayed_work\n");
 699         mutex_lock(&monc->mutex);
 700         if (monc->hunting) {
 701                 __close_session(monc);
 702                 __open_session(monc);  /* continue hunting */
 703         } else {
 704                 ceph_con_keepalive(monc->con);
 705
 706                 __validate_auth(monc);
 707
 708                 if (monc->auth->ops->is_authenticated(monc->auth))
 709                         __send_subscribe(monc);
 710         }
 711         __schedule_delayed(monc);
 712         mutex_unlock(&monc->mutex);
 713 }
 714
 715 /*
 716  * On startup, we build a temporary monmap populated with the IPs
 717  * provided by mount(2).
 718  */
 719 static int build_initial_monmap(struct ceph_mon_client *monc)
 720 {
 721         struct ceph_options *opt = monc->client->options;
 722         struct ceph_entity_addr *mon_addr = opt->mon_addr;
 723         int num_mon = opt->num_mon;
 724         int i;
 725
 726         /* build initial monmap */
 727         monc->monmap = kzalloc(sizeof(*monc->monmap) +
 728                                num_mon*sizeof(monc->monmap->mon_inst[0]),
 729                                GFP_KERNEL);
 730         if (!monc->monmap)
 731                 return -ENOMEM;
 732         for (i = 0; i < num_mon; i++) {
 733                 monc->monmap->mon_inst[i].addr = mon_addr[i];
 734                 monc->monmap->mon_inst[i].addr.nonce = 0;
 735                 monc->monmap->mon_inst[i].name.type =
 736                         CEPH_ENTITY_TYPE_MON;
 737                 monc->monmap->mon_inst[i].name.num = cpu_to_le64(i);
 738         }
 739         monc->monmap->num_mon = num_mon;
 740         monc->have_fsid = false;
 741         return 0;
 742 }
 743
 744 int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
 745 {
 746         int err = 0;
 747
 748         dout("init\n");
 749         memset(monc, 0, sizeof(*monc));
 750         monc->client = cl;
 751         monc->monmap = NULL;
 752         mutex_init(&monc->mutex);
 753
 754         err = build_initial_monmap(monc);
 755         if (err)
 756                 goto out;
 757
 758         monc->con = NULL;
 759
 760         /* authentication */
 761         monc->auth = ceph_auth_init(cl->options->name,
 762                                     cl->options->key);
 763         if (IS_ERR(monc->auth))
 764                 return PTR_ERR(monc->auth);
 765         monc->auth->want_keys =
 766                 CEPH_ENTITY_TYPE_AUTH | CEPH_ENTITY_TYPE_MON |
 767                 CEPH_ENTITY_TYPE_OSD | CEPH_ENTITY_TYPE_MDS;
 768
 769         /* msgs */
 770         err = -ENOMEM;
 771         monc->m_subscribe_ack = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE_ACK,
 772                                      sizeof(struct ceph_mon_subscribe_ack),
 773                                      GFP_NOFS);
 774         if (!monc->m_subscribe_ack)
 775                 goto out_monmap;
 776
 777         monc->m_subscribe = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 96, GFP_NOFS);
 778         if (!monc->m_subscribe)
 779                 goto out_subscribe_ack;
 780
 781         monc->m_auth_reply = ceph_msg_new(CEPH_MSG_AUTH_REPLY, 4096, GFP_NOFS);
 782         if (!monc->m_auth_reply)
 783                 goto out_subscribe;
 784
 785         monc->m_auth = ceph_msg_new(CEPH_MSG_AUTH, 4096, GFP_NOFS);
 786         monc->pending_auth = 0;
 787         if (!monc->m_auth)
 788                 goto out_auth_reply;
 789
 790         monc->cur_mon = -1;
 791         monc->hunting = true;
 792         monc->sub_renew_after = jiffies;
 793         monc->sub_sent = 0;
 794
 795         INIT_DELAYED_WORK(&monc->delayed_work, delayed_work);
 796         monc->generic_request_tree = RB_ROOT;
 797         monc->num_generic_requests = 0;
 798         monc->last_tid = 0;
 799
 800         monc->have_mdsmap = 0;
 801         monc->have_osdmap = 0;
 802         monc->want_next_osdmap = 1;
 803         return 0;
 804
 805 out_auth_reply:
 806         ceph_msg_put(monc->m_auth_reply);
 807 out_subscribe:
 808         ceph_msg_put(monc->m_subscribe);
 809 out_subscribe_ack:
 810         ceph_msg_put(monc->m_subscribe_ack);
 811 out_monmap:
 812         kfree(monc->monmap);
 813 out:
 814         return err;
 815 }
 816 EXPORT_SYMBOL(ceph_monc_init);
 817
 818 void ceph_monc_stop(struct ceph_mon_client *monc)
 819 {
 820         dout("stop\n");
 821         cancel_delayed_work_sync(&monc->delayed_work);
 822
 823         mutex_lock(&monc->mutex);
 824         __close_session(monc);
 825         if (monc->con) {
 826                 monc->con->private = NULL;
 827                 monc->con->ops->put(monc->con);
 828                 monc->con = NULL;
 829         }
 830         mutex_unlock(&monc->mutex);
 831
 832         ceph_auth_destroy(monc->auth);
 833
 834         ceph_msg_put(monc->m_auth);
 835         ceph_msg_put(monc->m_auth_reply);
 836         ceph_msg_put(monc->m_subscribe);
 837         ceph_msg_put(monc->m_subscribe_ack);
 838
 839         kfree(monc->monmap);
 840 }
 841 EXPORT_SYMBOL(ceph_monc_stop);
 842
 843 static void handle_auth_reply(struct ceph_mon_client *monc,
 844                               struct ceph_msg *msg)
 845 {
 846         int ret;
 847         int was_auth = 0;
 848
 849         mutex_lock(&monc->mutex);
 850         if (monc->auth->ops)
 851                 was_auth = monc->auth->ops->is_authenticated(monc->auth);
 852         monc->pending_auth = 0;
 853         ret = ceph_handle_auth_reply(monc->auth, msg->front.iov_base,
 854                                      msg->front.iov_len,
 855                                      monc->m_auth->front.iov_base,
 856                                      monc->m_auth->front_max);
 857         if (ret < 0) {
 858                 monc->client->auth_err = ret;
 859                 wake_up_all(&monc->client->auth_wq);
 860         } else if (ret > 0) {
 861                 __send_prepared_auth_request(monc, ret);
 862         } else if (!was_auth && monc->auth->ops->is_authenticated(monc->auth)) {
 863                 dout("authenticated, starting session\n");
 864
 865                 monc->client->msgr->inst.name.type = CEPH_ENTITY_TYPE_CLIENT;
 866                 monc->client->msgr->inst.name.num =
 867                                         cpu_to_le64(monc->auth->global_id);
 868
 869                 __send_subscribe(monc);
 870                 __resend_generic_request(monc);
 871         }
 872         mutex_unlock(&monc->mutex);
 873 }
 874
 875 static int __validate_auth(struct ceph_mon_client *monc)
 876 {
 877         int ret;
 878
 879         if (monc->pending_auth)
 880                 return 0;
 881
 882         ret = ceph_build_auth(monc->auth, monc->m_auth->front.iov_base,
 883                               monc->m_auth->front_max);
 884         if (ret <= 0)
 885                 return ret; /* either an error, or no need to authenticate */
 886         __send_prepared_auth_request(monc, ret);
 887         return 0;
 888 }
 889
 890 int ceph_monc_validate_auth(struct ceph_mon_client *monc)
 891 {
 892         int ret;
 893
 894         mutex_lock(&monc->mutex);
 895         ret = __validate_auth(monc);
 896         mutex_unlock(&monc->mutex);
 897         return ret;
 898 }
 899 EXPORT_SYMBOL(ceph_monc_validate_auth);
 900
 901 /*
 902  * handle incoming message
 903  */
 904 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
 905 {
 906         struct ceph_mon_client *monc = con->private;
 907         int type = le16_to_cpu(msg->hdr.type);
 908
 909         if (!monc)
 910                 return;
 911
 912         switch (type) {
 913         case CEPH_MSG_AUTH_REPLY:
 914                 handle_auth_reply(monc, msg);
 915                 break;
 916
 917         case CEPH_MSG_MON_SUBSCRIBE_ACK:
 918                 handle_subscribe_ack(monc, msg);
 919                 break;
 920
 921         case CEPH_MSG_STATFS_REPLY:
 922                 handle_statfs_reply(monc, msg);
 923                 break;
 924
 925         case CEPH_MSG_POOLOP_REPLY:
 926                 handle_poolop_reply(monc, msg);
 927                 break;
 928
 929         case CEPH_MSG_MON_MAP:
 930                 ceph_monc_handle_map(monc, msg);
 931                 break;
 932
 933         case CEPH_MSG_OSD_MAP:
 934                 ceph_osdc_handle_map(&monc->client->osdc, msg);
 935                 break;
 936
 937         default:
 938                 /* can the chained handler handle it? */
 939                 if (monc->client->extra_mon_dispatch &&
 940                     monc->client->extra_mon_dispatch(monc->client, msg) == 0)
 941                         break;
 942
 943                 pr_err("received unknown message type %d %s\n", type,
 944                        ceph_msg_type_name(type));
 945         }
 946         ceph_msg_put(msg);
 947 }
 948
 949 /*
 950  * Allocate memory for incoming message
 951  */
 952 static struct ceph_msg *mon_alloc_msg(struct ceph_connection *con,
 953                                       struct ceph_msg_header *hdr,
 954                                       int *skip)
 955 {
 956         struct ceph_mon_client *monc = con->private;
 957         int type = le16_to_cpu(hdr->type);
 958         int front_len = le32_to_cpu(hdr->front_len);
 959         struct ceph_msg *m = NULL;
 960
 961         *skip = 0;
 962
 963         switch (type) {
 964         case CEPH_MSG_MON_SUBSCRIBE_ACK:
 965                 m = ceph_msg_get(monc->m_subscribe_ack);
 966                 break;
 967         case CEPH_MSG_POOLOP_REPLY:
 968         case CEPH_MSG_STATFS_REPLY:
 969                 return get_generic_reply(con, hdr, skip);
 970         case CEPH_MSG_AUTH_REPLY:
 971                 m = ceph_msg_get(monc->m_auth_reply);
 972                 break;
 973         case CEPH_MSG_MON_MAP:
 974         case CEPH_MSG_MDS_MAP:
 975         case CEPH_MSG_OSD_MAP:
 976                 m = ceph_msg_new(type, front_len, GFP_NOFS);
 977                 break;
 978         }
 979
 980         if (!m) {
 981                 pr_info("alloc_msg unknown type %d\n", type);
 982                 *skip = 1;
 983         }
 984         return m;
 985 }
 986
 987 /*
 988  * If the monitor connection resets, pick a new monitor and resubmit
 989  * any pending requests.
 990  */
 991 static void mon_fault(struct ceph_connection *con)
 992 {
 993         struct ceph_mon_client *monc = con->private;
 994
 995         if (!monc)
 996                 return;
 997
 998         dout("mon_fault\n");
 999         mutex_lock(&monc->mutex);
1000         if (!con->private)
1001                 goto out;
1002
1003         if (monc->con && !monc->hunting)
1004                 pr_info("mon%d %s session lost, "
1005                         "hunting for new mon\n", monc->cur_mon,
1006                         ceph_pr_addr(&monc->con->peer_addr.in_addr));
1007
1008         __close_session(monc);
1009         if (!monc->hunting) {
1010                 /* start hunting */
1011                 monc->hunting = true;
1012                 __open_session(monc);
1013         } else {
1014                 /* already hunting, let's wait a bit */
1015                 __schedule_delayed(monc);
1016         }
1017 out:
1018         mutex_unlock(&monc->mutex);
1019 }
1020
1021 static const struct ceph_connection_operations mon_con_ops = {
1022         .get = ceph_con_get,
1023         .put = ceph_con_put,
1024         .dispatch = dispatch,
1025         .fault = mon_fault,
1026         .alloc_msg = mon_alloc_msg,
1027 };