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, 2015, 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/completion.h>
  39 #include "../../include/linux/lnet/lib-lnet.h"
  40
  41 static int   accept_port    = 988;
  42 static int   accept_backlog = 127;
  43 static int   accept_timeout = 5;
  44
  45 static struct {
  46         int                     pta_shutdown;
  47         struct socket           *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 EXPORT_SYMBOL(lnet_acceptor_port);
  57
  58 static inline int
  59 lnet_accept_magic(__u32 magic, __u32 constant)
  60 {
  61         return (magic == constant ||
  62                 magic == __swab32(constant));
  63 }
  64
  65 static char *accept = "secure";
  66
  67 module_param(accept, charp, 0444);
  68 MODULE_PARM_DESC(accept, "Accept connections (secure|all|none)");
  69 module_param(accept_port, int, 0444);
  70 MODULE_PARM_DESC(accept_port, "Acceptor's port (same on all nodes)");
  71 module_param(accept_backlog, int, 0444);
  72 MODULE_PARM_DESC(accept_backlog, "Acceptor's listen backlog");
  73 module_param(accept_timeout, int, 0644);
  74 MODULE_PARM_DESC(accept_timeout, "Acceptor's timeout (seconds)");
  75
  76 static char *accept_type;
  77
  78 static int
  79 lnet_acceptor_get_tunables(void)
  80 {
  81         /*
  82          * Userland acceptor uses 'accept_type' instead of 'accept', due to
  83          * conflict with 'accept(2)', but kernel acceptor still uses 'accept'
  84          * for compatibility. Hence the trick.
  85          */
  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 refused: check that Lustre is running on that node.\n",
 105                         libcfs_nid2str(peer_nid),
 106                         &peer_ip, peer_port);
 107                 break;
 108         case -EHOSTUNREACH:
 109         case -ENETUNREACH:
 110                 CNETERR("Connection to %s at host %pI4h was unreachable: the network or that node may be down, or Lustre may be misconfigured.\n",
 111                         libcfs_nid2str(peer_nid), &peer_ip);
 112                 break;
 113         case -ETIMEDOUT:
 114                 CNETERR("Connection to %s at host %pI4h on port %d took too long: that node may be hung or experiencing high load.\n",
 115                         libcfs_nid2str(peer_nid),
 116                         &peer_ip, peer_port);
 117                 break;
 118         case -ECONNRESET:
 119                 LCONSOLE_ERROR_MSG(0x11b, "Connection to %s at host %pI4h on port %d was reset: is it running a compatible version of Lustre and is %s one of its NIDs?\n",
 120                                    libcfs_nid2str(peer_nid),
 121                                    &peer_ip, peer_port,
 122                                    libcfs_nid2str(peer_nid));
 123                 break;
 124         case -EPROTO:
 125                 LCONSOLE_ERROR_MSG(0x11c, "Protocol error connecting to %s at host %pI4h on port %d: is it running a compatible version of Lustre?\n",
 126                                    libcfs_nid2str(peer_nid),
 127                                    &peer_ip, peer_port);
 128                 break;
 129         case -EADDRINUSE:
 130                 LCONSOLE_ERROR_MSG(0x11d, "No privileged ports available to connect to %s at host %pI4h on port %d\n",
 131                                    libcfs_nid2str(peer_nid),
 132                                    &peer_ip, peer_port);
 133                 break;
 134         default:
 135                 LCONSOLE_ERROR_MSG(0x11e, "Unexpected error %d connecting to %s at host %pI4h on port %d\n",
 136                                    rc, libcfs_nid2str(peer_nid),
 137                                    &peer_ip, peer_port);
 138                 break;
 139         }
 140 }
 141 EXPORT_SYMBOL(lnet_connect_console_error);
 142
 143 int
 144 lnet_connect(struct socket **sockp, lnet_nid_t peer_nid,
 145              __u32 local_ip, __u32 peer_ip, int peer_port)
 146 {
 147         lnet_acceptor_connreq_t cr;
 148         struct socket *sock;
 149         int rc;
 150         int port;
 151         int fatal;
 152
 153         CLASSERT(sizeof(cr) <= 16);         /* not too big to be on the stack */
 154
 155         for (port = LNET_ACCEPTOR_MAX_RESERVED_PORT;
 156              port >= LNET_ACCEPTOR_MIN_RESERVED_PORT;
 157              --port) {
 158                 /* Iterate through reserved ports. */
 159
 160                 rc = lnet_sock_connect(&sock, &fatal, local_ip, port, peer_ip,
 161                                        peer_port);
 162                 if (rc != 0) {
 163                         if (fatal)
 164                                 goto failed;
 165                         continue;
 166                 }
 167
 168                 CLASSERT(LNET_PROTO_ACCEPTOR_VERSION == 1);
 169
 170                 cr.acr_magic   = LNET_PROTO_ACCEPTOR_MAGIC;
 171                 cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 172                 cr.acr_nid     = peer_nid;
 173
 174                 if (the_lnet.ln_testprotocompat != 0) {
 175                         /* single-shot proto check */
 176                         lnet_net_lock(LNET_LOCK_EX);
 177                         if ((the_lnet.ln_testprotocompat & 4) != 0) {
 178                                 cr.acr_version++;
 179                                 the_lnet.ln_testprotocompat &= ~4;
 180                         }
 181                         if ((the_lnet.ln_testprotocompat & 8) != 0) {
 182                                 cr.acr_magic = LNET_PROTO_MAGIC;
 183                                 the_lnet.ln_testprotocompat &= ~8;
 184                         }
 185                         lnet_net_unlock(LNET_LOCK_EX);
 186                 }
 187
 188                 rc = lnet_sock_write(sock, &cr, sizeof(cr), accept_timeout);
 189                 if (rc != 0)
 190                         goto failed_sock;
 191
 192                 *sockp = sock;
 193                 return 0;
 194         }
 195
 196         rc = -EADDRINUSE;
 197         goto failed;
 198
 199  failed_sock:
 200         sock_release(sock);
 201  failed:
 202         lnet_connect_console_error(rc, peer_nid, peer_ip, peer_port);
 203         return rc;
 204 }
 205 EXPORT_SYMBOL(lnet_connect);
 206
 207 /* Below is the code common for both kernel and MT user-space */
 208
 209 static int
 210 lnet_accept(struct socket *sock, __u32 magic)
 211 {
 212         lnet_acceptor_connreq_t cr;
 213         __u32 peer_ip;
 214         int peer_port;
 215         int rc;
 216         int flip;
 217         lnet_ni_t *ni;
 218         char *str;
 219
 220         LASSERT(sizeof(cr) <= 16);           /* not too big for the stack */
 221
 222         rc = lnet_sock_getaddr(sock, 1, &peer_ip, &peer_port);
 223         LASSERT(rc == 0);                     /* we succeeded before */
 224
 225         if (!lnet_accept_magic(magic, LNET_PROTO_ACCEPTOR_MAGIC)) {
 226                 if (lnet_accept_magic(magic, LNET_PROTO_MAGIC)) {
 227                         /*
 228                          * future version compatibility!
 229                          * When LNET unifies protocols over all LNDs, the first
 230                          * thing sent will be a version query. I send back
 231                          * LNET_PROTO_ACCEPTOR_MAGIC to tell her I'm "old"
 232                          */
 233                         memset(&cr, 0, sizeof(cr));
 234                         cr.acr_magic = LNET_PROTO_ACCEPTOR_MAGIC;
 235                         cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 236                         rc = lnet_sock_write(sock, &cr, sizeof(cr),
 237                                              accept_timeout);
 238
 239                         if (rc != 0)
 240                                 CERROR("Error sending magic+version in response to LNET magic from %pI4h: %d\n",
 241                                        &peer_ip, rc);
 242                         return -EPROTO;
 243                 }
 244
 245                 if (magic == le32_to_cpu(LNET_PROTO_TCP_MAGIC))
 246                         str = "'old' socknal/tcpnal";
 247                 else
 248                         str = "unrecognised";
 249
 250                 LCONSOLE_ERROR_MSG(0x11f, "Refusing connection from %pI4h magic %08x: %s acceptor protocol\n",
 251                                    &peer_ip, magic, str);
 252                 return -EPROTO;
 253         }
 254
 255         flip = (magic != LNET_PROTO_ACCEPTOR_MAGIC);
 256
 257         rc = lnet_sock_read(sock, &cr.acr_version, sizeof(cr.acr_version),
 258                             accept_timeout);
 259         if (rc != 0) {
 260                 CERROR("Error %d reading connection request version from %pI4h\n",
 261                        rc, &peer_ip);
 262                 return -EIO;
 263         }
 264
 265         if (flip)
 266                 __swab32s(&cr.acr_version);
 267
 268         if (cr.acr_version != LNET_PROTO_ACCEPTOR_VERSION) {
 269                 /*
 270                  * future version compatibility!
 271                  * An acceptor-specific protocol rev will first send a version
 272                  * query.  I send back my current version to tell her I'm
 273                  * "old".
 274                  */
 275                 int peer_version = cr.acr_version;
 276
 277                 memset(&cr, 0, sizeof(cr));
 278                 cr.acr_magic = LNET_PROTO_ACCEPTOR_MAGIC;
 279                 cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 280
 281                 rc = lnet_sock_write(sock, &cr, sizeof(cr), accept_timeout);
 282                 if (rc != 0)
 283                         CERROR("Error sending magic+version in response to version %d from %pI4h: %d\n",
 284                                peer_version, &peer_ip, rc);
 285                 return -EPROTO;
 286         }
 287
 288         rc = lnet_sock_read(sock, &cr.acr_nid,
 289                             sizeof(cr) -
 290                             offsetof(lnet_acceptor_connreq_t, acr_nid),
 291                             accept_timeout);
 292         if (rc != 0) {
 293                 CERROR("Error %d reading connection request from %pI4h\n",
 294                        rc, &peer_ip);
 295                 return -EIO;
 296         }
 297
 298         if (flip)
 299                 __swab64s(&cr.acr_nid);
 300
 301         ni = lnet_net2ni(LNET_NIDNET(cr.acr_nid));
 302         if (!ni ||             /* no matching net */
 303             ni->ni_nid != cr.acr_nid) { /* right NET, wrong NID! */
 304                 if (ni)
 305                         lnet_ni_decref(ni);
 306                 LCONSOLE_ERROR_MSG(0x120, "Refusing connection from %pI4h for %s: No matching NI\n",
 307                                    &peer_ip, libcfs_nid2str(cr.acr_nid));
 308                 return -EPERM;
 309         }
 310
 311         if (!ni->ni_lnd->lnd_accept) {
 312                 /* This catches a request for the loopback LND */
 313                 lnet_ni_decref(ni);
 314                 LCONSOLE_ERROR_MSG(0x121, "Refusing connection from %pI4h for %s: NI doesn not accept IP connections\n",
 315                                    &peer_ip, libcfs_nid2str(cr.acr_nid));
 316                 return -EPERM;
 317         }
 318
 319         CDEBUG(D_NET, "Accept %s from %pI4h\n",
 320                libcfs_nid2str(cr.acr_nid), &peer_ip);
 321
 322         rc = ni->ni_lnd->lnd_accept(ni, sock);
 323
 324         lnet_ni_decref(ni);
 325         return rc;
 326 }
 327
 328 static int
 329 lnet_acceptor(void *arg)
 330 {
 331         struct socket *newsock;
 332         int rc;
 333         __u32 magic;
 334         __u32 peer_ip;
 335         int peer_port;
 336         int secure = (int)((long_ptr_t)arg);
 337
 338         LASSERT(!lnet_acceptor_state.pta_sock);
 339
 340         cfs_block_allsigs();
 341
 342         rc = lnet_sock_listen(&lnet_acceptor_state.pta_sock, 0, accept_port,
 343                               accept_backlog);
 344         if (rc != 0) {
 345                 if (rc == -EADDRINUSE)
 346                         LCONSOLE_ERROR_MSG(0x122, "Can't start acceptor on port %d: port already in use\n",
 347                                            accept_port);
 348                 else
 349                         LCONSOLE_ERROR_MSG(0x123, "Can't start acceptor on port %d: unexpected error %d\n",
 350                                            accept_port, rc);
 351
 352                 lnet_acceptor_state.pta_sock = NULL;
 353         } else {
 354                 LCONSOLE(0, "Accept %s, port %d\n", accept_type, accept_port);
 355         }
 356
 357         /* set init status and unblock parent */
 358         lnet_acceptor_state.pta_shutdown = rc;
 359         complete(&lnet_acceptor_state.pta_signal);
 360
 361         if (rc != 0)
 362                 return rc;
 363
 364         while (!lnet_acceptor_state.pta_shutdown) {
 365                 rc = lnet_sock_accept(&newsock, lnet_acceptor_state.pta_sock);
 366                 if (rc != 0) {
 367                         if (rc != -EAGAIN) {
 368                                 CWARN("Accept error %d: pausing...\n", rc);
 369                                 set_current_state(TASK_UNINTERRUPTIBLE);
 370                                 schedule_timeout(cfs_time_seconds(1));
 371                         }
 372                         continue;
 373                 }
 374
 375                 /* maybe the LNet acceptor thread has been waken */
 376                 if (lnet_acceptor_state.pta_shutdown) {
 377                         sock_release(newsock);
 378                         break;
 379                 }
 380
 381                 rc = lnet_sock_getaddr(newsock, 1, &peer_ip, &peer_port);
 382                 if (rc != 0) {
 383                         CERROR("Can't determine new connection's address\n");
 384                         goto failed;
 385                 }
 386
 387                 if (secure && peer_port > LNET_ACCEPTOR_MAX_RESERVED_PORT) {
 388                         CERROR("Refusing connection from %pI4h: insecure port %d\n",
 389                                &peer_ip, peer_port);
 390                         goto failed;
 391                 }
 392
 393                 rc = lnet_sock_read(newsock, &magic, sizeof(magic),
 394                                     accept_timeout);
 395                 if (rc != 0) {
 396                         CERROR("Error %d reading connection request from %pI4h\n",
 397                                rc, &peer_ip);
 398                         goto failed;
 399                 }
 400
 401                 rc = lnet_accept(newsock, magic);
 402                 if (rc != 0)
 403                         goto failed;
 404
 405                 continue;
 406
 407 failed:
 408                 sock_release(newsock);
 409         }
 410
 411         sock_release(lnet_acceptor_state.pta_sock);
 412         lnet_acceptor_state.pta_sock = NULL;
 413
 414         CDEBUG(D_NET, "Acceptor stopping\n");
 415
 416         /* unblock lnet_acceptor_stop() */
 417         complete(&lnet_acceptor_state.pta_signal);
 418         return 0;
 419 }
 420
 421 static inline int
 422 accept2secure(const char *acc, long *sec)
 423 {
 424         if (!strcmp(acc, "secure")) {
 425                 *sec = 1;
 426                 return 1;
 427         } else if (!strcmp(acc, "all")) {
 428                 *sec = 0;
 429                 return 1;
 430         } else if (!strcmp(acc, "none")) {
 431                 return 0;
 432         }
 433
 434         LCONSOLE_ERROR_MSG(0x124, "Can't parse 'accept=\"%s\"'\n",
 435                            acc);
 436         return -EINVAL;
 437 }
 438
 439 int
 440 lnet_acceptor_start(void)
 441 {
 442         int rc;
 443         long rc2;
 444         long secure;
 445
 446         LASSERT(!lnet_acceptor_state.pta_sock);
 447
 448         rc = lnet_acceptor_get_tunables();
 449         if (rc != 0)
 450                 return rc;
 451
 452         init_completion(&lnet_acceptor_state.pta_signal);
 453         rc = accept2secure(accept_type, &secure);
 454         if (rc <= 0)
 455                 return rc;
 456
 457         if (lnet_count_acceptor_nis() == 0)  /* not required */
 458                 return 0;
 459
 460         rc2 = PTR_ERR(kthread_run(lnet_acceptor,
 461                                   (void *)(ulong_ptr_t)secure,
 462                                   "acceptor_%03ld", secure));
 463         if (IS_ERR_VALUE(rc2)) {
 464                 CERROR("Can't start acceptor thread: %ld\n", rc2);
 465
 466                 return -ESRCH;
 467         }
 468
 469         /* wait for acceptor to startup */
 470         wait_for_completion(&lnet_acceptor_state.pta_signal);
 471
 472         if (!lnet_acceptor_state.pta_shutdown) {
 473                 /* started OK */
 474                 LASSERT(lnet_acceptor_state.pta_sock);
 475                 return 0;
 476         }
 477
 478         LASSERT(!lnet_acceptor_state.pta_sock);
 479
 480         return -ENETDOWN;
 481 }
 482
 483 void
 484 lnet_acceptor_stop(void)
 485 {
 486         if (!lnet_acceptor_state.pta_sock) /* not running */
 487                 return;
 488
 489         lnet_acceptor_state.pta_shutdown = 1;
 490         wake_up_all(sk_sleep(lnet_acceptor_state.pta_sock->sk));
 491
 492         /* block until acceptor signals exit */
 493         wait_for_completion(&lnet_acceptor_state.pta_signal);
 494 }