drivers/staging/lustre/lnet/lnet/acceptor.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2012, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36
  37 #define DEBUG_SUBSYSTEM S_LNET
  38 #include <linux/lnet/lib-lnet.h>
  39
  40
  41 static int   accept_port    = 988;
  42 static int   accept_backlog = 127;
  43 static int   accept_timeout = 5;
  44
  45 struct {
  46         int                     pta_shutdown;
  47         socket_t                *pta_sock;
  48         struct completion       pta_signal;
  49 } lnet_acceptor_state;
  50
  51 int
  52 lnet_acceptor_port(void)
  53 {
  54         return accept_port;
  55 }
  56
  57 static inline int
  58 lnet_accept_magic(__u32 magic, __u32 constant)
  59 {
  60         return (magic == constant ||
  61                 magic == __swab32(constant));
  62 }
  63
  64
  65 EXPORT_SYMBOL(lnet_acceptor_port);
  66
  67 static char *accept = "secure";
  68
  69 CFS_MODULE_PARM(accept, "s", charp, 0444,
  70                 "Accept connections (secure|all|none)");
  71 CFS_MODULE_PARM(accept_port, "i", int, 0444,
  72                 "Acceptor's port (same on all nodes)");
  73 CFS_MODULE_PARM(accept_backlog, "i", int, 0444,
  74                 "Acceptor's listen backlog");
  75 CFS_MODULE_PARM(accept_timeout, "i", int, 0644,
  76                 "Acceptor's timeout (seconds)");
  77
  78 static char *accept_type = NULL;
  79
  80 int
  81 lnet_acceptor_get_tunables(void)
  82 {
  83         /* Userland acceptor uses 'accept_type' instead of 'accept', due to
  84          * conflict with 'accept(2)', but kernel acceptor still uses 'accept'
  85          * for compatibility. Hence the trick. */
  86         accept_type = accept;
  87         return 0;
  88 }
  89
  90 int
  91 lnet_acceptor_timeout(void)
  92 {
  93         return accept_timeout;
  94 }
  95 EXPORT_SYMBOL(lnet_acceptor_timeout);
  96
  97 void
  98 lnet_connect_console_error (int rc, lnet_nid_t peer_nid,
  99                            __u32 peer_ip, int peer_port)
 100 {
 101         switch (rc) {
 102         /* "normal" errors */
 103         case -ECONNREFUSED:
 104                 CNETERR("Connection to %s at host %pI4h on port %d was "
 105                         "refused: check that Lustre is running on that node.\n",
 106                         libcfs_nid2str(peer_nid),
 107                         &peer_ip, peer_port);
 108                 break;
 109         case -EHOSTUNREACH:
 110         case -ENETUNREACH:
 111                 CNETERR("Connection to %s at host %pI4h "
 112                         "was unreachable: the network or that node may "
 113                         "be down, or Lustre may be misconfigured.\n",
 114                         libcfs_nid2str(peer_nid), &peer_ip);
 115                 break;
 116         case -ETIMEDOUT:
 117                 CNETERR("Connection to %s at host %pI4h on "
 118                         "port %d took too long: that node may be hung "
 119                         "or experiencing high load.\n",
 120                         libcfs_nid2str(peer_nid),
 121                         &peer_ip, peer_port);
 122                 break;
 123         case -ECONNRESET:
 124                 LCONSOLE_ERROR_MSG(0x11b, "Connection to %s at host %pI4h"
 125                                    " on port %d was reset: "
 126                                    "is it running a compatible version of "
 127                                    "Lustre and is %s one of its NIDs?\n",
 128                                    libcfs_nid2str(peer_nid),
 129                                    &peer_ip, peer_port,
 130                                    libcfs_nid2str(peer_nid));
 131                 break;
 132         case -EPROTO:
 133                 LCONSOLE_ERROR_MSG(0x11c, "Protocol error connecting to %s at "
 134                                    "host %pI4h on port %d: is it running "
 135                                    "a compatible version of Lustre?\n",
 136                                    libcfs_nid2str(peer_nid),
 137                                    &peer_ip, peer_port);
 138                 break;
 139         case -EADDRINUSE:
 140                 LCONSOLE_ERROR_MSG(0x11d, "No privileged ports available to "
 141                                    "connect to %s at host %pI4h on port "
 142                                    "%d\n", libcfs_nid2str(peer_nid),
 143                                    &peer_ip, peer_port);
 144                 break;
 145         default:
 146                 LCONSOLE_ERROR_MSG(0x11e, "Unexpected error %d connecting to %s"
 147                                    " at host %pI4h on port %d\n", rc,
 148                                    libcfs_nid2str(peer_nid),
 149                                    &peer_ip, peer_port);
 150                 break;
 151         }
 152 }
 153 EXPORT_SYMBOL(lnet_connect_console_error);
 154
 155 int
 156 lnet_connect(socket_t **sockp, lnet_nid_t peer_nid,
 157             __u32 local_ip, __u32 peer_ip, int peer_port)
 158 {
 159         lnet_acceptor_connreq_t cr;
 160         socket_t           *sock;
 161         int                  rc;
 162         int                  port;
 163         int                  fatal;
 164
 165         CLASSERT (sizeof(cr) <= 16);        /* not too big to be on the stack */
 166
 167         for (port = LNET_ACCEPTOR_MAX_RESERVED_PORT;
 168              port >= LNET_ACCEPTOR_MIN_RESERVED_PORT;
 169              --port) {
 170                 /* Iterate through reserved ports. */
 171
 172                 rc = libcfs_sock_connect(&sock, &fatal,
 173                                          local_ip, port,
 174                                          peer_ip, peer_port);
 175                 if (rc != 0) {
 176                         if (fatal)
 177                                 goto failed;
 178                         continue;
 179                 }
 180
 181                 CLASSERT (LNET_PROTO_ACCEPTOR_VERSION == 1);
 182
 183                 cr.acr_magic   = LNET_PROTO_ACCEPTOR_MAGIC;
 184                 cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 185                 cr.acr_nid     = peer_nid;
 186
 187                 if (the_lnet.ln_testprotocompat != 0) {
 188                         /* single-shot proto check */
 189                         lnet_net_lock(LNET_LOCK_EX);
 190                         if ((the_lnet.ln_testprotocompat & 4) != 0) {
 191                                 cr.acr_version++;
 192                                 the_lnet.ln_testprotocompat &= ~4;
 193                         }
 194                         if ((the_lnet.ln_testprotocompat & 8) != 0) {
 195                                 cr.acr_magic = LNET_PROTO_MAGIC;
 196                                 the_lnet.ln_testprotocompat &= ~8;
 197                         }
 198                         lnet_net_unlock(LNET_LOCK_EX);
 199                 }
 200
 201                 rc = libcfs_sock_write(sock, &cr, sizeof(cr),
 202                                        accept_timeout);
 203                 if (rc != 0)
 204                         goto failed_sock;
 205
 206                 *sockp = sock;
 207                 return 0;
 208         }
 209
 210         rc = -EADDRINUSE;
 211         goto failed;
 212
 213  failed_sock:
 214         libcfs_sock_release(sock);
 215  failed:
 216         lnet_connect_console_error(rc, peer_nid, peer_ip, peer_port);
 217         return rc;
 218 }
 219 EXPORT_SYMBOL(lnet_connect);
 220
 221
 222 /* Below is the code common for both kernel and MT user-space */
 223
 224 int
 225 lnet_accept(socket_t *sock, __u32 magic)
 226 {
 227         lnet_acceptor_connreq_t cr;
 228         __u32              peer_ip;
 229         int                  peer_port;
 230         int                  rc;
 231         int                  flip;
 232         lnet_ni_t             *ni;
 233         char               *str;
 234
 235         LASSERT (sizeof(cr) <= 16);          /* not too big for the stack */
 236
 237         rc = libcfs_sock_getaddr(sock, 1, &peer_ip, &peer_port);
 238         LASSERT (rc == 0);                    /* we succeeded before */
 239
 240         if (!lnet_accept_magic(magic, LNET_PROTO_ACCEPTOR_MAGIC)) {
 241
 242                 if (lnet_accept_magic(magic, LNET_PROTO_MAGIC)) {
 243                         /* future version compatibility!
 244                          * When LNET unifies protocols over all LNDs, the first
 245                          * thing sent will be a version query.  I send back
 246                          * LNET_PROTO_ACCEPTOR_MAGIC to tell her I'm "old" */
 247
 248                         memset (&cr, 0, sizeof(cr));
 249                         cr.acr_magic = LNET_PROTO_ACCEPTOR_MAGIC;
 250                         cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 251                         rc = libcfs_sock_write(sock, &cr, sizeof(cr),
 252                                                accept_timeout);
 253
 254                         if (rc != 0)
 255                                 CERROR("Error sending magic+version in response"
 256                                        "to LNET magic from %pI4h: %d\n",
 257                                        &peer_ip, rc);
 258                         return -EPROTO;
 259                 }
 260
 261                 if (magic == le32_to_cpu(LNET_PROTO_TCP_MAGIC))
 262                         str = "'old' socknal/tcpnal";
 263                 else if (lnet_accept_magic(magic, LNET_PROTO_RA_MAGIC))
 264                         str = "'old' ranal";
 265                 else
 266                         str = "unrecognised";
 267
 268                 LCONSOLE_ERROR_MSG(0x11f, "Refusing connection from %pI4h"
 269                                    " magic %08x: %s acceptor protocol\n",
 270                                    &peer_ip, magic, str);
 271                 return -EPROTO;
 272         }
 273
 274         flip = (magic != LNET_PROTO_ACCEPTOR_MAGIC);
 275
 276         rc = libcfs_sock_read(sock, &cr.acr_version,
 277                               sizeof(cr.acr_version),
 278                               accept_timeout);
 279         if (rc != 0) {
 280                 CERROR("Error %d reading connection request version from "
 281                        "%pI4h\n", rc, &peer_ip);
 282                 return -EIO;
 283         }
 284
 285         if (flip)
 286                 __swab32s(&cr.acr_version);
 287
 288         if (cr.acr_version != LNET_PROTO_ACCEPTOR_VERSION) {
 289                 /* future version compatibility!
 290                  * An acceptor-specific protocol rev will first send a version
 291                  * query.  I send back my current version to tell her I'm
 292                  * "old". */
 293                 int peer_version = cr.acr_version;
 294
 295                 memset (&cr, 0, sizeof(cr));
 296                 cr.acr_magic = LNET_PROTO_ACCEPTOR_MAGIC;
 297                 cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 298
 299                 rc = libcfs_sock_write(sock, &cr, sizeof(cr),
 300                                        accept_timeout);
 301
 302                 if (rc != 0)
 303                         CERROR("Error sending magic+version in response"
 304                                "to version %d from %pI4h: %d\n",
 305                                peer_version, &peer_ip, rc);
 306                 return -EPROTO;
 307         }
 308
 309         rc = libcfs_sock_read(sock, &cr.acr_nid,
 310                               sizeof(cr) -
 311                               offsetof(lnet_acceptor_connreq_t, acr_nid),
 312                               accept_timeout);
 313         if (rc != 0) {
 314                 CERROR("Error %d reading connection request from "
 315                        "%pI4h\n", rc, &peer_ip);
 316                 return -EIO;
 317         }
 318
 319         if (flip)
 320                 __swab64s(&cr.acr_nid);
 321
 322         ni = lnet_net2ni(LNET_NIDNET(cr.acr_nid));
 323         if (ni == NULL ||              /* no matching net */
 324             ni->ni_nid != cr.acr_nid) { /* right NET, wrong NID! */
 325                 if (ni != NULL)
 326                         lnet_ni_decref(ni);
 327                 LCONSOLE_ERROR_MSG(0x120, "Refusing connection from %pI4h"
 328                                    " for %s: No matching NI\n",
 329                                    &peer_ip, libcfs_nid2str(cr.acr_nid));
 330                 return -EPERM;
 331         }
 332
 333         if (ni->ni_lnd->lnd_accept == NULL) {
 334                 /* This catches a request for the loopback LND */
 335                 lnet_ni_decref(ni);
 336                 LCONSOLE_ERROR_MSG(0x121, "Refusing connection from %pI4h"
 337                                   " for %s: NI doesn not accept IP connections\n",
 338                                   &peer_ip, libcfs_nid2str(cr.acr_nid));
 339                 return -EPERM;
 340         }
 341
 342         CDEBUG(D_NET, "Accept %s from %pI4h\n",
 343                libcfs_nid2str(cr.acr_nid), &peer_ip);
 344
 345         rc = ni->ni_lnd->lnd_accept(ni, sock);
 346
 347         lnet_ni_decref(ni);
 348         return rc;
 349 }
 350
 351 int
 352 lnet_acceptor(void *arg)
 353 {
 354         socket_t  *newsock;
 355         int         rc;
 356         __u32     magic;
 357         __u32     peer_ip;
 358         int         peer_port;
 359         int         secure = (int)((long_ptr_t)arg);
 360
 361         LASSERT (lnet_acceptor_state.pta_sock == NULL);
 362
 363         cfs_block_allsigs();
 364
 365         rc = libcfs_sock_listen(&lnet_acceptor_state.pta_sock,
 366                                 0, accept_port, accept_backlog);
 367         if (rc != 0) {
 368                 if (rc == -EADDRINUSE)
 369                         LCONSOLE_ERROR_MSG(0x122, "Can't start acceptor on port"
 370                                            " %d: port already in use\n",
 371                                            accept_port);
 372                 else
 373                         LCONSOLE_ERROR_MSG(0x123, "Can't start acceptor on port "
 374                                            "%d: unexpected error %d\n",
 375                                            accept_port, rc);
 376
 377                 lnet_acceptor_state.pta_sock = NULL;
 378         } else {
 379                 LCONSOLE(0, "Accept %s, port %d\n", accept_type, accept_port);
 380         }
 381
 382         /* set init status and unblock parent */
 383         lnet_acceptor_state.pta_shutdown = rc;
 384         complete(&lnet_acceptor_state.pta_signal);
 385
 386         if (rc != 0)
 387                 return rc;
 388
 389         while (!lnet_acceptor_state.pta_shutdown) {
 390
 391                 rc = libcfs_sock_accept(&newsock, lnet_acceptor_state.pta_sock);
 392                 if (rc != 0) {
 393                         if (rc != -EAGAIN) {
 394                                 CWARN("Accept error %d: pausing...\n", rc);
 395                                 cfs_pause(cfs_time_seconds(1));
 396                         }
 397                         continue;
 398                 }
 399
 400                 /* maybe we're waken up with libcfs_sock_abort_accept() */
 401                 if (lnet_acceptor_state.pta_shutdown) {
 402                         libcfs_sock_release(newsock);
 403                         break;
 404                 }
 405
 406                 rc = libcfs_sock_getaddr(newsock, 1, &peer_ip, &peer_port);
 407                 if (rc != 0) {
 408                         CERROR("Can't determine new connection's address\n");
 409                         goto failed;
 410                 }
 411
 412                 if (secure && peer_port > LNET_ACCEPTOR_MAX_RESERVED_PORT) {
 413                         CERROR("Refusing connection from %pI4h: "
 414                                "insecure port %d\n",
 415                                &peer_ip, peer_port);
 416                         goto failed;
 417                 }
 418
 419                 rc = libcfs_sock_read(newsock, &magic, sizeof(magic),
 420                                       accept_timeout);
 421                 if (rc != 0) {
 422                         CERROR("Error %d reading connection request from "
 423                                "%pI4h\n", rc, &peer_ip);
 424                         goto failed;
 425                 }
 426
 427                 rc = lnet_accept(newsock, magic);
 428                 if (rc != 0)
 429                         goto failed;
 430
 431                 continue;
 432
 433         failed:
 434                 libcfs_sock_release(newsock);
 435         }
 436
 437         libcfs_sock_release(lnet_acceptor_state.pta_sock);
 438         lnet_acceptor_state.pta_sock = NULL;
 439
 440         CDEBUG(D_NET, "Acceptor stopping\n");
 441
 442         /* unblock lnet_acceptor_stop() */
 443         complete(&lnet_acceptor_state.pta_signal);
 444         return 0;
 445 }
 446
 447 static inline int
 448 accept2secure(const char *acc, long *sec)
 449 {
 450         if (!strcmp(acc, "secure")) {
 451                 *sec = 1;
 452                 return 1;
 453         } else if (!strcmp(acc, "all")) {
 454                 *sec = 0;
 455                 return 1;
 456         } else if (!strcmp(acc, "none")) {
 457                 return 0;
 458         } else {
 459                 LCONSOLE_ERROR_MSG(0x124, "Can't parse 'accept=\"%s\"'\n",
 460                                    acc);
 461                 return -EINVAL;
 462         }
 463 }
 464
 465 int
 466 lnet_acceptor_start(void)
 467 {
 468         int  rc;
 469         long rc2;
 470         long secure;
 471
 472         LASSERT (lnet_acceptor_state.pta_sock == NULL);
 473
 474         rc = lnet_acceptor_get_tunables();
 475         if (rc != 0)
 476                 return rc;
 477
 478
 479         init_completion(&lnet_acceptor_state.pta_signal);
 480         rc = accept2secure(accept_type, &secure);
 481         if (rc <= 0) {
 482                 fini_completion(&lnet_acceptor_state.pta_signal);
 483                 return rc;
 484         }
 485
 486         if (lnet_count_acceptor_nis() == 0)  /* not required */
 487                 return 0;
 488
 489         rc2 = PTR_ERR(kthread_run(lnet_acceptor,
 490                                   (void *)(ulong_ptr_t)secure,
 491                                   "acceptor_%03ld", secure));
 492         if (IS_ERR_VALUE(rc2)) {
 493                 CERROR("Can't start acceptor thread: %ld\n", rc2);
 494                 fini_completion(&lnet_acceptor_state.pta_signal);
 495
 496                 return -ESRCH;
 497         }
 498
 499         /* wait for acceptor to startup */
 500         wait_for_completion(&lnet_acceptor_state.pta_signal);
 501
 502         if (!lnet_acceptor_state.pta_shutdown) {
 503                 /* started OK */
 504                 LASSERT(lnet_acceptor_state.pta_sock != NULL);
 505                 return 0;
 506         }
 507
 508         LASSERT(lnet_acceptor_state.pta_sock == NULL);
 509         fini_completion(&lnet_acceptor_state.pta_signal);
 510
 511         return -ENETDOWN;
 512 }
 513
 514 void
 515 lnet_acceptor_stop(void)
 516 {
 517         if (lnet_acceptor_state.pta_sock == NULL) /* not running */
 518                 return;
 519
 520         lnet_acceptor_state.pta_shutdown = 1;
 521         libcfs_sock_abort_accept(lnet_acceptor_state.pta_sock);
 522
 523         /* block until acceptor signals exit */
 524         wait_for_completion(&lnet_acceptor_state.pta_signal);
 525
 526         fini_completion(&lnet_acceptor_state.pta_signal);
 527 }