lowcomms.c revision 7a936ce71eed7b887b8a0d6c54dd8a9072f71c9f
1/****************************************************************************** 2******************************************************************************* 3** 4** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. 5** Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved. 6** 7** This copyrighted material is made available to anyone wishing to use, 8** modify, copy, or redistribute it subject to the terms and conditions 9** of the GNU General Public License v.2. 10** 11******************************************************************************* 12******************************************************************************/ 13 14/* 15 * lowcomms.c 16 * 17 * This is the "low-level" comms layer. 18 * 19 * It is responsible for sending/receiving messages 20 * from other nodes in the cluster. 21 * 22 * Cluster nodes are referred to by their nodeids. nodeids are 23 * simply 32 bit numbers to the locking module - if they need to 24 * be expanded for the cluster infrastructure then that is it's 25 * responsibility. It is this layer's 26 * responsibility to resolve these into IP address or 27 * whatever it needs for inter-node communication. 28 * 29 * The comms level is two kernel threads that deal mainly with 30 * the receiving of messages from other nodes and passing them 31 * up to the mid-level comms layer (which understands the 32 * message format) for execution by the locking core, and 33 * a send thread which does all the setting up of connections 34 * to remote nodes and the sending of data. Threads are not allowed 35 * to send their own data because it may cause them to wait in times 36 * of high load. Also, this way, the sending thread can collect together 37 * messages bound for one node and send them in one block. 38 * 39 * lowcomms will choose to use wither TCP or SCTP as its transport layer 40 * depending on the configuration variable 'protocol'. This should be set 41 * to 0 (default) for TCP or 1 for SCTP. It shouldbe configured using a 42 * cluster-wide mechanism as it must be the same on all nodes of the cluster 43 * for the DLM to function. 44 * 45 */ 46 47#include <asm/ioctls.h> 48#include <net/sock.h> 49#include <net/tcp.h> 50#include <linux/pagemap.h> 51#include <linux/idr.h> 52#include <linux/file.h> 53#include <linux/mutex.h> 54#include <linux/sctp.h> 55#include <net/sctp/user.h> 56 57#include "dlm_internal.h" 58#include "lowcomms.h" 59#include "midcomms.h" 60#include "config.h" 61 62#define NEEDED_RMEM (4*1024*1024) 63 64struct cbuf { 65 unsigned int base; 66 unsigned int len; 67 unsigned int mask; 68}; 69 70static void cbuf_add(struct cbuf *cb, int n) 71{ 72 cb->len += n; 73} 74 75static int cbuf_data(struct cbuf *cb) 76{ 77 return ((cb->base + cb->len) & cb->mask); 78} 79 80static void cbuf_init(struct cbuf *cb, int size) 81{ 82 cb->base = cb->len = 0; 83 cb->mask = size-1; 84} 85 86static void cbuf_eat(struct cbuf *cb, int n) 87{ 88 cb->len -= n; 89 cb->base += n; 90 cb->base &= cb->mask; 91} 92 93static bool cbuf_empty(struct cbuf *cb) 94{ 95 return cb->len == 0; 96} 97 98struct connection { 99 struct socket *sock; /* NULL if not connected */ 100 uint32_t nodeid; /* So we know who we are in the list */ 101 struct mutex sock_mutex; 102 unsigned long flags; 103#define CF_READ_PENDING 1 104#define CF_WRITE_PENDING 2 105#define CF_CONNECT_PENDING 3 106#define CF_INIT_PENDING 4 107#define CF_IS_OTHERCON 5 108 struct list_head writequeue; /* List of outgoing writequeue_entries */ 109 spinlock_t writequeue_lock; 110 int (*rx_action) (struct connection *); /* What to do when active */ 111 void (*connect_action) (struct connection *); /* What to do to connect */ 112 struct page *rx_page; 113 struct cbuf cb; 114 int retries; 115#define MAX_CONNECT_RETRIES 3 116 int sctp_assoc; 117 struct connection *othercon; 118 struct work_struct rwork; /* Receive workqueue */ 119 struct work_struct swork; /* Send workqueue */ 120}; 121#define sock2con(x) ((struct connection *)(x)->sk_user_data) 122 123/* An entry waiting to be sent */ 124struct writequeue_entry { 125 struct list_head list; 126 struct page *page; 127 int offset; 128 int len; 129 int end; 130 int users; 131 struct connection *con; 132}; 133 134static struct sockaddr_storage *dlm_local_addr[DLM_MAX_ADDR_COUNT]; 135static int dlm_local_count; 136 137/* Work queues */ 138static struct workqueue_struct *recv_workqueue; 139static struct workqueue_struct *send_workqueue; 140 141static DEFINE_IDR(connections_idr); 142static DEFINE_MUTEX(connections_lock); 143static int max_nodeid; 144static struct kmem_cache *con_cache; 145 146static void process_recv_sockets(struct work_struct *work); 147static void process_send_sockets(struct work_struct *work); 148 149/* 150 * If 'allocation' is zero then we don't attempt to create a new 151 * connection structure for this node. 152 */ 153static struct connection *__nodeid2con(int nodeid, gfp_t alloc) 154{ 155 struct connection *con = NULL; 156 int r; 157 int n; 158 159 con = idr_find(&connections_idr, nodeid); 160 if (con || !alloc) 161 return con; 162 163 r = idr_pre_get(&connections_idr, alloc); 164 if (!r) 165 return NULL; 166 167 con = kmem_cache_zalloc(con_cache, alloc); 168 if (!con) 169 return NULL; 170 171 r = idr_get_new_above(&connections_idr, con, nodeid, &n); 172 if (r) { 173 kmem_cache_free(con_cache, con); 174 return NULL; 175 } 176 177 if (n != nodeid) { 178 idr_remove(&connections_idr, n); 179 kmem_cache_free(con_cache, con); 180 return NULL; 181 } 182 183 con->nodeid = nodeid; 184 mutex_init(&con->sock_mutex); 185 INIT_LIST_HEAD(&con->writequeue); 186 spin_lock_init(&con->writequeue_lock); 187 INIT_WORK(&con->swork, process_send_sockets); 188 INIT_WORK(&con->rwork, process_recv_sockets); 189 190 /* Setup action pointers for child sockets */ 191 if (con->nodeid) { 192 struct connection *zerocon = idr_find(&connections_idr, 0); 193 194 con->connect_action = zerocon->connect_action; 195 if (!con->rx_action) 196 con->rx_action = zerocon->rx_action; 197 } 198 199 if (nodeid > max_nodeid) 200 max_nodeid = nodeid; 201 202 return con; 203} 204 205static struct connection *nodeid2con(int nodeid, gfp_t allocation) 206{ 207 struct connection *con; 208 209 mutex_lock(&connections_lock); 210 con = __nodeid2con(nodeid, allocation); 211 mutex_unlock(&connections_lock); 212 213 return con; 214} 215 216/* This is a bit drastic, but only called when things go wrong */ 217static struct connection *assoc2con(int assoc_id) 218{ 219 int i; 220 struct connection *con; 221 222 mutex_lock(&connections_lock); 223 for (i=0; i<=max_nodeid; i++) { 224 con = __nodeid2con(i, 0); 225 if (con && con->sctp_assoc == assoc_id) { 226 mutex_unlock(&connections_lock); 227 return con; 228 } 229 } 230 mutex_unlock(&connections_lock); 231 return NULL; 232} 233 234static int nodeid_to_addr(int nodeid, struct sockaddr *retaddr) 235{ 236 struct sockaddr_storage addr; 237 int error; 238 239 if (!dlm_local_count) 240 return -1; 241 242 error = dlm_nodeid_to_addr(nodeid, &addr); 243 if (error) 244 return error; 245 246 if (dlm_local_addr[0]->ss_family == AF_INET) { 247 struct sockaddr_in *in4 = (struct sockaddr_in *) &addr; 248 struct sockaddr_in *ret4 = (struct sockaddr_in *) retaddr; 249 ret4->sin_addr.s_addr = in4->sin_addr.s_addr; 250 } else { 251 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *) &addr; 252 struct sockaddr_in6 *ret6 = (struct sockaddr_in6 *) retaddr; 253 memcpy(&ret6->sin6_addr, &in6->sin6_addr, 254 sizeof(in6->sin6_addr)); 255 } 256 257 return 0; 258} 259 260/* Data available on socket or listen socket received a connect */ 261static void lowcomms_data_ready(struct sock *sk, int count_unused) 262{ 263 struct connection *con = sock2con(sk); 264 if (con && !test_and_set_bit(CF_READ_PENDING, &con->flags)) 265 queue_work(recv_workqueue, &con->rwork); 266} 267 268static void lowcomms_write_space(struct sock *sk) 269{ 270 struct connection *con = sock2con(sk); 271 272 if (con && !test_and_set_bit(CF_WRITE_PENDING, &con->flags)) 273 queue_work(send_workqueue, &con->swork); 274} 275 276static inline void lowcomms_connect_sock(struct connection *con) 277{ 278 if (!test_and_set_bit(CF_CONNECT_PENDING, &con->flags)) 279 queue_work(send_workqueue, &con->swork); 280} 281 282static void lowcomms_state_change(struct sock *sk) 283{ 284 if (sk->sk_state == TCP_ESTABLISHED) 285 lowcomms_write_space(sk); 286} 287 288/* Make a socket active */ 289static int add_sock(struct socket *sock, struct connection *con) 290{ 291 con->sock = sock; 292 293 /* Install a data_ready callback */ 294 con->sock->sk->sk_data_ready = lowcomms_data_ready; 295 con->sock->sk->sk_write_space = lowcomms_write_space; 296 con->sock->sk->sk_state_change = lowcomms_state_change; 297 con->sock->sk->sk_user_data = con; 298 return 0; 299} 300 301/* Add the port number to an IPv6 or 4 sockaddr and return the address 302 length */ 303static void make_sockaddr(struct sockaddr_storage *saddr, uint16_t port, 304 int *addr_len) 305{ 306 saddr->ss_family = dlm_local_addr[0]->ss_family; 307 if (saddr->ss_family == AF_INET) { 308 struct sockaddr_in *in4_addr = (struct sockaddr_in *)saddr; 309 in4_addr->sin_port = cpu_to_be16(port); 310 *addr_len = sizeof(struct sockaddr_in); 311 memset(&in4_addr->sin_zero, 0, sizeof(in4_addr->sin_zero)); 312 } else { 313 struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)saddr; 314 in6_addr->sin6_port = cpu_to_be16(port); 315 *addr_len = sizeof(struct sockaddr_in6); 316 } 317 memset((char *)saddr + *addr_len, 0, sizeof(struct sockaddr_storage) - *addr_len); 318} 319 320/* Close a remote connection and tidy up */ 321static void close_connection(struct connection *con, bool and_other) 322{ 323 mutex_lock(&con->sock_mutex); 324 325 if (con->sock) { 326 sock_release(con->sock); 327 con->sock = NULL; 328 } 329 if (con->othercon && and_other) { 330 /* Will only re-enter once. */ 331 close_connection(con->othercon, false); 332 } 333 if (con->rx_page) { 334 __free_page(con->rx_page); 335 con->rx_page = NULL; 336 } 337 338 con->retries = 0; 339 mutex_unlock(&con->sock_mutex); 340} 341 342/* We only send shutdown messages to nodes that are not part of the cluster */ 343static void sctp_send_shutdown(sctp_assoc_t associd) 344{ 345 static char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; 346 struct msghdr outmessage; 347 struct cmsghdr *cmsg; 348 struct sctp_sndrcvinfo *sinfo; 349 int ret; 350 struct connection *con; 351 352 con = nodeid2con(0,0); 353 BUG_ON(con == NULL); 354 355 outmessage.msg_name = NULL; 356 outmessage.msg_namelen = 0; 357 outmessage.msg_control = outcmsg; 358 outmessage.msg_controllen = sizeof(outcmsg); 359 outmessage.msg_flags = MSG_EOR; 360 361 cmsg = CMSG_FIRSTHDR(&outmessage); 362 cmsg->cmsg_level = IPPROTO_SCTP; 363 cmsg->cmsg_type = SCTP_SNDRCV; 364 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); 365 outmessage.msg_controllen = cmsg->cmsg_len; 366 sinfo = CMSG_DATA(cmsg); 367 memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); 368 369 sinfo->sinfo_flags |= MSG_EOF; 370 sinfo->sinfo_assoc_id = associd; 371 372 ret = kernel_sendmsg(con->sock, &outmessage, NULL, 0, 0); 373 374 if (ret != 0) 375 log_print("send EOF to node failed: %d", ret); 376} 377 378/* INIT failed but we don't know which node... 379 restart INIT on all pending nodes */ 380static void sctp_init_failed(void) 381{ 382 int i; 383 struct connection *con; 384 385 mutex_lock(&connections_lock); 386 for (i=1; i<=max_nodeid; i++) { 387 con = __nodeid2con(i, 0); 388 if (!con) 389 continue; 390 con->sctp_assoc = 0; 391 if (test_and_clear_bit(CF_CONNECT_PENDING, &con->flags)) { 392 if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags)) { 393 queue_work(send_workqueue, &con->swork); 394 } 395 } 396 } 397 mutex_unlock(&connections_lock); 398} 399 400/* Something happened to an association */ 401static void process_sctp_notification(struct connection *con, 402 struct msghdr *msg, char *buf) 403{ 404 union sctp_notification *sn = (union sctp_notification *)buf; 405 406 if (sn->sn_header.sn_type == SCTP_ASSOC_CHANGE) { 407 switch (sn->sn_assoc_change.sac_state) { 408 409 case SCTP_COMM_UP: 410 case SCTP_RESTART: 411 { 412 /* Check that the new node is in the lockspace */ 413 struct sctp_prim prim; 414 int nodeid; 415 int prim_len, ret; 416 int addr_len; 417 struct connection *new_con; 418 struct file *file; 419 sctp_peeloff_arg_t parg; 420 int parglen = sizeof(parg); 421 422 /* 423 * We get this before any data for an association. 424 * We verify that the node is in the cluster and 425 * then peel off a socket for it. 426 */ 427 if ((int)sn->sn_assoc_change.sac_assoc_id <= 0) { 428 log_print("COMM_UP for invalid assoc ID %d", 429 (int)sn->sn_assoc_change.sac_assoc_id); 430 sctp_init_failed(); 431 return; 432 } 433 memset(&prim, 0, sizeof(struct sctp_prim)); 434 prim_len = sizeof(struct sctp_prim); 435 prim.ssp_assoc_id = sn->sn_assoc_change.sac_assoc_id; 436 437 ret = kernel_getsockopt(con->sock, 438 IPPROTO_SCTP, 439 SCTP_PRIMARY_ADDR, 440 (char*)&prim, 441 &prim_len); 442 if (ret < 0) { 443 log_print("getsockopt/sctp_primary_addr on " 444 "new assoc %d failed : %d", 445 (int)sn->sn_assoc_change.sac_assoc_id, 446 ret); 447 448 /* Retry INIT later */ 449 new_con = assoc2con(sn->sn_assoc_change.sac_assoc_id); 450 if (new_con) 451 clear_bit(CF_CONNECT_PENDING, &con->flags); 452 return; 453 } 454 make_sockaddr(&prim.ssp_addr, 0, &addr_len); 455 if (dlm_addr_to_nodeid(&prim.ssp_addr, &nodeid)) { 456 int i; 457 unsigned char *b=(unsigned char *)&prim.ssp_addr; 458 log_print("reject connect from unknown addr"); 459 for (i=0; i<sizeof(struct sockaddr_storage);i++) 460 printk("%02x ", b[i]); 461 printk("\n"); 462 sctp_send_shutdown(prim.ssp_assoc_id); 463 return; 464 } 465 466 new_con = nodeid2con(nodeid, GFP_KERNEL); 467 if (!new_con) 468 return; 469 470 /* Peel off a new sock */ 471 parg.associd = sn->sn_assoc_change.sac_assoc_id; 472 ret = kernel_getsockopt(con->sock, IPPROTO_SCTP, 473 SCTP_SOCKOPT_PEELOFF, 474 (void *)&parg, &parglen); 475 if (ret) { 476 log_print("Can't peel off a socket for " 477 "connection %d to node %d: err=%d\n", 478 parg.associd, nodeid, ret); 479 } 480 file = fget(parg.sd); 481 new_con->sock = SOCKET_I(file->f_dentry->d_inode); 482 add_sock(new_con->sock, new_con); 483 fput(file); 484 put_unused_fd(parg.sd); 485 486 log_print("got new/restarted association %d nodeid %d", 487 (int)sn->sn_assoc_change.sac_assoc_id, nodeid); 488 489 /* Send any pending writes */ 490 clear_bit(CF_CONNECT_PENDING, &new_con->flags); 491 clear_bit(CF_INIT_PENDING, &con->flags); 492 if (!test_and_set_bit(CF_WRITE_PENDING, &new_con->flags)) { 493 queue_work(send_workqueue, &new_con->swork); 494 } 495 if (!test_and_set_bit(CF_READ_PENDING, &new_con->flags)) 496 queue_work(recv_workqueue, &new_con->rwork); 497 } 498 break; 499 500 case SCTP_COMM_LOST: 501 case SCTP_SHUTDOWN_COMP: 502 { 503 con = assoc2con(sn->sn_assoc_change.sac_assoc_id); 504 if (con) { 505 con->sctp_assoc = 0; 506 } 507 } 508 break; 509 510 /* We don't know which INIT failed, so clear the PENDING flags 511 * on them all. if assoc_id is zero then it will then try 512 * again */ 513 514 case SCTP_CANT_STR_ASSOC: 515 { 516 log_print("Can't start SCTP association - retrying"); 517 sctp_init_failed(); 518 } 519 break; 520 521 default: 522 log_print("unexpected SCTP assoc change id=%d state=%d", 523 (int)sn->sn_assoc_change.sac_assoc_id, 524 sn->sn_assoc_change.sac_state); 525 } 526 } 527} 528 529/* Data received from remote end */ 530static int receive_from_sock(struct connection *con) 531{ 532 int ret = 0; 533 struct msghdr msg = {}; 534 struct kvec iov[2]; 535 unsigned len; 536 int r; 537 int call_again_soon = 0; 538 int nvec; 539 char incmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; 540 541 mutex_lock(&con->sock_mutex); 542 543 if (con->sock == NULL) { 544 ret = -EAGAIN; 545 goto out_close; 546 } 547 548 if (con->rx_page == NULL) { 549 /* 550 * This doesn't need to be atomic, but I think it should 551 * improve performance if it is. 552 */ 553 con->rx_page = alloc_page(GFP_ATOMIC); 554 if (con->rx_page == NULL) 555 goto out_resched; 556 cbuf_init(&con->cb, PAGE_CACHE_SIZE); 557 } 558 559 /* Only SCTP needs these really */ 560 memset(&incmsg, 0, sizeof(incmsg)); 561 msg.msg_control = incmsg; 562 msg.msg_controllen = sizeof(incmsg); 563 564 /* 565 * iov[0] is the bit of the circular buffer between the current end 566 * point (cb.base + cb.len) and the end of the buffer. 567 */ 568 iov[0].iov_len = con->cb.base - cbuf_data(&con->cb); 569 iov[0].iov_base = page_address(con->rx_page) + cbuf_data(&con->cb); 570 iov[1].iov_len = 0; 571 nvec = 1; 572 573 /* 574 * iov[1] is the bit of the circular buffer between the start of the 575 * buffer and the start of the currently used section (cb.base) 576 */ 577 if (cbuf_data(&con->cb) >= con->cb.base) { 578 iov[0].iov_len = PAGE_CACHE_SIZE - cbuf_data(&con->cb); 579 iov[1].iov_len = con->cb.base; 580 iov[1].iov_base = page_address(con->rx_page); 581 nvec = 2; 582 } 583 len = iov[0].iov_len + iov[1].iov_len; 584 585 r = ret = kernel_recvmsg(con->sock, &msg, iov, nvec, len, 586 MSG_DONTWAIT | MSG_NOSIGNAL); 587 if (ret <= 0) 588 goto out_close; 589 590 /* Process SCTP notifications */ 591 if (msg.msg_flags & MSG_NOTIFICATION) { 592 msg.msg_control = incmsg; 593 msg.msg_controllen = sizeof(incmsg); 594 595 process_sctp_notification(con, &msg, 596 page_address(con->rx_page) + con->cb.base); 597 mutex_unlock(&con->sock_mutex); 598 return 0; 599 } 600 BUG_ON(con->nodeid == 0); 601 602 if (ret == len) 603 call_again_soon = 1; 604 cbuf_add(&con->cb, ret); 605 ret = dlm_process_incoming_buffer(con->nodeid, 606 page_address(con->rx_page), 607 con->cb.base, con->cb.len, 608 PAGE_CACHE_SIZE); 609 if (ret == -EBADMSG) { 610 log_print("lowcomms: addr=%p, base=%u, len=%u, " 611 "iov_len=%u, iov_base[0]=%p, read=%d", 612 page_address(con->rx_page), con->cb.base, con->cb.len, 613 len, iov[0].iov_base, r); 614 } 615 if (ret < 0) 616 goto out_close; 617 cbuf_eat(&con->cb, ret); 618 619 if (cbuf_empty(&con->cb) && !call_again_soon) { 620 __free_page(con->rx_page); 621 con->rx_page = NULL; 622 } 623 624 if (call_again_soon) 625 goto out_resched; 626 mutex_unlock(&con->sock_mutex); 627 return 0; 628 629out_resched: 630 if (!test_and_set_bit(CF_READ_PENDING, &con->flags)) 631 queue_work(recv_workqueue, &con->rwork); 632 mutex_unlock(&con->sock_mutex); 633 return -EAGAIN; 634 635out_close: 636 mutex_unlock(&con->sock_mutex); 637 if (ret != -EAGAIN) { 638 close_connection(con, false); 639 /* Reconnect when there is something to send */ 640 } 641 /* Don't return success if we really got EOF */ 642 if (ret == 0) 643 ret = -EAGAIN; 644 645 return ret; 646} 647 648/* Listening socket is busy, accept a connection */ 649static int tcp_accept_from_sock(struct connection *con) 650{ 651 int result; 652 struct sockaddr_storage peeraddr; 653 struct socket *newsock; 654 int len; 655 int nodeid; 656 struct connection *newcon; 657 struct connection *addcon; 658 659 memset(&peeraddr, 0, sizeof(peeraddr)); 660 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM, 661 IPPROTO_TCP, &newsock); 662 if (result < 0) 663 return -ENOMEM; 664 665 mutex_lock_nested(&con->sock_mutex, 0); 666 667 result = -ENOTCONN; 668 if (con->sock == NULL) 669 goto accept_err; 670 671 newsock->type = con->sock->type; 672 newsock->ops = con->sock->ops; 673 674 result = con->sock->ops->accept(con->sock, newsock, O_NONBLOCK); 675 if (result < 0) 676 goto accept_err; 677 678 /* Get the connected socket's peer */ 679 memset(&peeraddr, 0, sizeof(peeraddr)); 680 if (newsock->ops->getname(newsock, (struct sockaddr *)&peeraddr, 681 &len, 2)) { 682 result = -ECONNABORTED; 683 goto accept_err; 684 } 685 686 /* Get the new node's NODEID */ 687 make_sockaddr(&peeraddr, 0, &len); 688 if (dlm_addr_to_nodeid(&peeraddr, &nodeid)) { 689 log_print("connect from non cluster node"); 690 sock_release(newsock); 691 mutex_unlock(&con->sock_mutex); 692 return -1; 693 } 694 695 log_print("got connection from %d", nodeid); 696 697 /* Check to see if we already have a connection to this node. This 698 * could happen if the two nodes initiate a connection at roughly 699 * the same time and the connections cross on the wire. 700 * In this case we store the incoming one in "othercon" 701 */ 702 newcon = nodeid2con(nodeid, GFP_KERNEL); 703 if (!newcon) { 704 result = -ENOMEM; 705 goto accept_err; 706 } 707 mutex_lock_nested(&newcon->sock_mutex, 1); 708 if (newcon->sock) { 709 struct connection *othercon = newcon->othercon; 710 711 if (!othercon) { 712 othercon = kmem_cache_zalloc(con_cache, GFP_KERNEL); 713 if (!othercon) { 714 log_print("failed to allocate incoming socket"); 715 mutex_unlock(&newcon->sock_mutex); 716 result = -ENOMEM; 717 goto accept_err; 718 } 719 othercon->nodeid = nodeid; 720 othercon->rx_action = receive_from_sock; 721 mutex_init(&othercon->sock_mutex); 722 INIT_WORK(&othercon->swork, process_send_sockets); 723 INIT_WORK(&othercon->rwork, process_recv_sockets); 724 set_bit(CF_IS_OTHERCON, &othercon->flags); 725 } 726 if (!othercon->sock) { 727 newcon->othercon = othercon; 728 othercon->sock = newsock; 729 newsock->sk->sk_user_data = othercon; 730 add_sock(newsock, othercon); 731 addcon = othercon; 732 } 733 else { 734 printk("Extra connection from node %d attempted\n", nodeid); 735 result = -EAGAIN; 736 mutex_unlock(&newcon->sock_mutex); 737 goto accept_err; 738 } 739 } 740 else { 741 newsock->sk->sk_user_data = newcon; 742 newcon->rx_action = receive_from_sock; 743 add_sock(newsock, newcon); 744 addcon = newcon; 745 } 746 747 mutex_unlock(&newcon->sock_mutex); 748 749 /* 750 * Add it to the active queue in case we got data 751 * beween processing the accept adding the socket 752 * to the read_sockets list 753 */ 754 if (!test_and_set_bit(CF_READ_PENDING, &addcon->flags)) 755 queue_work(recv_workqueue, &addcon->rwork); 756 mutex_unlock(&con->sock_mutex); 757 758 return 0; 759 760accept_err: 761 mutex_unlock(&con->sock_mutex); 762 sock_release(newsock); 763 764 if (result != -EAGAIN) 765 log_print("error accepting connection from node: %d", result); 766 return result; 767} 768 769static void free_entry(struct writequeue_entry *e) 770{ 771 __free_page(e->page); 772 kfree(e); 773} 774 775/* Initiate an SCTP association. 776 This is a special case of send_to_sock() in that we don't yet have a 777 peeled-off socket for this association, so we use the listening socket 778 and add the primary IP address of the remote node. 779 */ 780static void sctp_init_assoc(struct connection *con) 781{ 782 struct sockaddr_storage rem_addr; 783 char outcmsg[CMSG_SPACE(sizeof(struct sctp_sndrcvinfo))]; 784 struct msghdr outmessage; 785 struct cmsghdr *cmsg; 786 struct sctp_sndrcvinfo *sinfo; 787 struct connection *base_con; 788 struct writequeue_entry *e; 789 int len, offset; 790 int ret; 791 int addrlen; 792 struct kvec iov[1]; 793 794 if (test_and_set_bit(CF_INIT_PENDING, &con->flags)) 795 return; 796 797 if (con->retries++ > MAX_CONNECT_RETRIES) 798 return; 799 800 log_print("Initiating association with node %d", con->nodeid); 801 802 if (nodeid_to_addr(con->nodeid, (struct sockaddr *)&rem_addr)) { 803 log_print("no address for nodeid %d", con->nodeid); 804 return; 805 } 806 base_con = nodeid2con(0, 0); 807 BUG_ON(base_con == NULL); 808 809 make_sockaddr(&rem_addr, dlm_config.ci_tcp_port, &addrlen); 810 811 outmessage.msg_name = &rem_addr; 812 outmessage.msg_namelen = addrlen; 813 outmessage.msg_control = outcmsg; 814 outmessage.msg_controllen = sizeof(outcmsg); 815 outmessage.msg_flags = MSG_EOR; 816 817 spin_lock(&con->writequeue_lock); 818 e = list_entry(con->writequeue.next, struct writequeue_entry, 819 list); 820 821 BUG_ON((struct list_head *) e == &con->writequeue); 822 823 len = e->len; 824 offset = e->offset; 825 spin_unlock(&con->writequeue_lock); 826 kmap(e->page); 827 828 /* Send the first block off the write queue */ 829 iov[0].iov_base = page_address(e->page)+offset; 830 iov[0].iov_len = len; 831 832 cmsg = CMSG_FIRSTHDR(&outmessage); 833 cmsg->cmsg_level = IPPROTO_SCTP; 834 cmsg->cmsg_type = SCTP_SNDRCV; 835 cmsg->cmsg_len = CMSG_LEN(sizeof(struct sctp_sndrcvinfo)); 836 sinfo = CMSG_DATA(cmsg); 837 memset(sinfo, 0x00, sizeof(struct sctp_sndrcvinfo)); 838 sinfo->sinfo_ppid = cpu_to_le32(dlm_our_nodeid()); 839 outmessage.msg_controllen = cmsg->cmsg_len; 840 841 ret = kernel_sendmsg(base_con->sock, &outmessage, iov, 1, len); 842 if (ret < 0) { 843 log_print("Send first packet to node %d failed: %d", 844 con->nodeid, ret); 845 846 /* Try again later */ 847 clear_bit(CF_CONNECT_PENDING, &con->flags); 848 clear_bit(CF_INIT_PENDING, &con->flags); 849 } 850 else { 851 spin_lock(&con->writequeue_lock); 852 e->offset += ret; 853 e->len -= ret; 854 855 if (e->len == 0 && e->users == 0) { 856 list_del(&e->list); 857 kunmap(e->page); 858 free_entry(e); 859 } 860 spin_unlock(&con->writequeue_lock); 861 } 862} 863 864/* Connect a new socket to its peer */ 865static void tcp_connect_to_sock(struct connection *con) 866{ 867 int result = -EHOSTUNREACH; 868 struct sockaddr_storage saddr, src_addr; 869 int addr_len; 870 struct socket *sock; 871 872 if (con->nodeid == 0) { 873 log_print("attempt to connect sock 0 foiled"); 874 return; 875 } 876 877 mutex_lock(&con->sock_mutex); 878 if (con->retries++ > MAX_CONNECT_RETRIES) 879 goto out; 880 881 /* Some odd races can cause double-connects, ignore them */ 882 if (con->sock) { 883 result = 0; 884 goto out; 885 } 886 887 /* Create a socket to communicate with */ 888 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM, 889 IPPROTO_TCP, &sock); 890 if (result < 0) 891 goto out_err; 892 893 memset(&saddr, 0, sizeof(saddr)); 894 if (dlm_nodeid_to_addr(con->nodeid, &saddr)) 895 goto out_err; 896 897 sock->sk->sk_user_data = con; 898 con->rx_action = receive_from_sock; 899 con->connect_action = tcp_connect_to_sock; 900 add_sock(sock, con); 901 902 /* Bind to our cluster-known address connecting to avoid 903 routing problems */ 904 memcpy(&src_addr, dlm_local_addr[0], sizeof(src_addr)); 905 make_sockaddr(&src_addr, 0, &addr_len); 906 result = sock->ops->bind(sock, (struct sockaddr *) &src_addr, 907 addr_len); 908 if (result < 0) { 909 log_print("could not bind for connect: %d", result); 910 /* This *may* not indicate a critical error */ 911 } 912 913 make_sockaddr(&saddr, dlm_config.ci_tcp_port, &addr_len); 914 915 log_print("connecting to %d", con->nodeid); 916 result = 917 sock->ops->connect(sock, (struct sockaddr *)&saddr, addr_len, 918 O_NONBLOCK); 919 if (result == -EINPROGRESS) 920 result = 0; 921 if (result == 0) 922 goto out; 923 924out_err: 925 if (con->sock) { 926 sock_release(con->sock); 927 con->sock = NULL; 928 } 929 /* 930 * Some errors are fatal and this list might need adjusting. For other 931 * errors we try again until the max number of retries is reached. 932 */ 933 if (result != -EHOSTUNREACH && result != -ENETUNREACH && 934 result != -ENETDOWN && result != EINVAL 935 && result != -EPROTONOSUPPORT) { 936 lowcomms_connect_sock(con); 937 result = 0; 938 } 939out: 940 mutex_unlock(&con->sock_mutex); 941 return; 942} 943 944static struct socket *tcp_create_listen_sock(struct connection *con, 945 struct sockaddr_storage *saddr) 946{ 947 struct socket *sock = NULL; 948 int result = 0; 949 int one = 1; 950 int addr_len; 951 952 if (dlm_local_addr[0]->ss_family == AF_INET) 953 addr_len = sizeof(struct sockaddr_in); 954 else 955 addr_len = sizeof(struct sockaddr_in6); 956 957 /* Create a socket to communicate with */ 958 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_STREAM, 959 IPPROTO_TCP, &sock); 960 if (result < 0) { 961 log_print("Can't create listening comms socket"); 962 goto create_out; 963 } 964 965 result = kernel_setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, 966 (char *)&one, sizeof(one)); 967 968 if (result < 0) { 969 log_print("Failed to set SO_REUSEADDR on socket: %d", result); 970 } 971 sock->sk->sk_user_data = con; 972 con->rx_action = tcp_accept_from_sock; 973 con->connect_action = tcp_connect_to_sock; 974 con->sock = sock; 975 976 /* Bind to our port */ 977 make_sockaddr(saddr, dlm_config.ci_tcp_port, &addr_len); 978 result = sock->ops->bind(sock, (struct sockaddr *) saddr, addr_len); 979 if (result < 0) { 980 log_print("Can't bind to port %d", dlm_config.ci_tcp_port); 981 sock_release(sock); 982 sock = NULL; 983 con->sock = NULL; 984 goto create_out; 985 } 986 result = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, 987 (char *)&one, sizeof(one)); 988 if (result < 0) { 989 log_print("Set keepalive failed: %d", result); 990 } 991 992 result = sock->ops->listen(sock, 5); 993 if (result < 0) { 994 log_print("Can't listen on port %d", dlm_config.ci_tcp_port); 995 sock_release(sock); 996 sock = NULL; 997 goto create_out; 998 } 999 1000create_out: 1001 return sock; 1002} 1003 1004/* Get local addresses */ 1005static void init_local(void) 1006{ 1007 struct sockaddr_storage sas, *addr; 1008 int i; 1009 1010 dlm_local_count = 0; 1011 for (i = 0; i < DLM_MAX_ADDR_COUNT - 1; i++) { 1012 if (dlm_our_addr(&sas, i)) 1013 break; 1014 1015 addr = kmalloc(sizeof(*addr), GFP_KERNEL); 1016 if (!addr) 1017 break; 1018 memcpy(addr, &sas, sizeof(*addr)); 1019 dlm_local_addr[dlm_local_count++] = addr; 1020 } 1021} 1022 1023/* Bind to an IP address. SCTP allows multiple address so it can do 1024 multi-homing */ 1025static int add_sctp_bind_addr(struct connection *sctp_con, 1026 struct sockaddr_storage *addr, 1027 int addr_len, int num) 1028{ 1029 int result = 0; 1030 1031 if (num == 1) 1032 result = kernel_bind(sctp_con->sock, 1033 (struct sockaddr *) addr, 1034 addr_len); 1035 else 1036 result = kernel_setsockopt(sctp_con->sock, SOL_SCTP, 1037 SCTP_SOCKOPT_BINDX_ADD, 1038 (char *)addr, addr_len); 1039 1040 if (result < 0) 1041 log_print("Can't bind to port %d addr number %d", 1042 dlm_config.ci_tcp_port, num); 1043 1044 return result; 1045} 1046 1047/* Initialise SCTP socket and bind to all interfaces */ 1048static int sctp_listen_for_all(void) 1049{ 1050 struct socket *sock = NULL; 1051 struct sockaddr_storage localaddr; 1052 struct sctp_event_subscribe subscribe; 1053 int result = -EINVAL, num = 1, i, addr_len; 1054 struct connection *con = nodeid2con(0, GFP_KERNEL); 1055 int bufsize = NEEDED_RMEM; 1056 1057 if (!con) 1058 return -ENOMEM; 1059 1060 log_print("Using SCTP for communications"); 1061 1062 result = sock_create_kern(dlm_local_addr[0]->ss_family, SOCK_SEQPACKET, 1063 IPPROTO_SCTP, &sock); 1064 if (result < 0) { 1065 log_print("Can't create comms socket, check SCTP is loaded"); 1066 goto out; 1067 } 1068 1069 /* Listen for events */ 1070 memset(&subscribe, 0, sizeof(subscribe)); 1071 subscribe.sctp_data_io_event = 1; 1072 subscribe.sctp_association_event = 1; 1073 subscribe.sctp_send_failure_event = 1; 1074 subscribe.sctp_shutdown_event = 1; 1075 subscribe.sctp_partial_delivery_event = 1; 1076 1077 result = kernel_setsockopt(sock, SOL_SOCKET, SO_RCVBUFFORCE, 1078 (char *)&bufsize, sizeof(bufsize)); 1079 if (result) 1080 log_print("Error increasing buffer space on socket %d", result); 1081 1082 result = kernel_setsockopt(sock, SOL_SCTP, SCTP_EVENTS, 1083 (char *)&subscribe, sizeof(subscribe)); 1084 if (result < 0) { 1085 log_print("Failed to set SCTP_EVENTS on socket: result=%d", 1086 result); 1087 goto create_delsock; 1088 } 1089 1090 /* Init con struct */ 1091 sock->sk->sk_user_data = con; 1092 con->sock = sock; 1093 con->sock->sk->sk_data_ready = lowcomms_data_ready; 1094 con->rx_action = receive_from_sock; 1095 con->connect_action = sctp_init_assoc; 1096 1097 /* Bind to all interfaces. */ 1098 for (i = 0; i < dlm_local_count; i++) { 1099 memcpy(&localaddr, dlm_local_addr[i], sizeof(localaddr)); 1100 make_sockaddr(&localaddr, dlm_config.ci_tcp_port, &addr_len); 1101 1102 result = add_sctp_bind_addr(con, &localaddr, addr_len, num); 1103 if (result) 1104 goto create_delsock; 1105 ++num; 1106 } 1107 1108 result = sock->ops->listen(sock, 5); 1109 if (result < 0) { 1110 log_print("Can't set socket listening"); 1111 goto create_delsock; 1112 } 1113 1114 return 0; 1115 1116create_delsock: 1117 sock_release(sock); 1118 con->sock = NULL; 1119out: 1120 return result; 1121} 1122 1123static int tcp_listen_for_all(void) 1124{ 1125 struct socket *sock = NULL; 1126 struct connection *con = nodeid2con(0, GFP_KERNEL); 1127 int result = -EINVAL; 1128 1129 if (!con) 1130 return -ENOMEM; 1131 1132 /* We don't support multi-homed hosts */ 1133 if (dlm_local_addr[1] != NULL) { 1134 log_print("TCP protocol can't handle multi-homed hosts, " 1135 "try SCTP"); 1136 return -EINVAL; 1137 } 1138 1139 log_print("Using TCP for communications"); 1140 1141 sock = tcp_create_listen_sock(con, dlm_local_addr[0]); 1142 if (sock) { 1143 add_sock(sock, con); 1144 result = 0; 1145 } 1146 else { 1147 result = -EADDRINUSE; 1148 } 1149 1150 return result; 1151} 1152 1153 1154 1155static struct writequeue_entry *new_writequeue_entry(struct connection *con, 1156 gfp_t allocation) 1157{ 1158 struct writequeue_entry *entry; 1159 1160 entry = kmalloc(sizeof(struct writequeue_entry), allocation); 1161 if (!entry) 1162 return NULL; 1163 1164 entry->page = alloc_page(allocation); 1165 if (!entry->page) { 1166 kfree(entry); 1167 return NULL; 1168 } 1169 1170 entry->offset = 0; 1171 entry->len = 0; 1172 entry->end = 0; 1173 entry->users = 0; 1174 entry->con = con; 1175 1176 return entry; 1177} 1178 1179void *dlm_lowcomms_get_buffer(int nodeid, int len, gfp_t allocation, char **ppc) 1180{ 1181 struct connection *con; 1182 struct writequeue_entry *e; 1183 int offset = 0; 1184 int users = 0; 1185 1186 con = nodeid2con(nodeid, allocation); 1187 if (!con) 1188 return NULL; 1189 1190 spin_lock(&con->writequeue_lock); 1191 e = list_entry(con->writequeue.prev, struct writequeue_entry, list); 1192 if ((&e->list == &con->writequeue) || 1193 (PAGE_CACHE_SIZE - e->end < len)) { 1194 e = NULL; 1195 } else { 1196 offset = e->end; 1197 e->end += len; 1198 users = e->users++; 1199 } 1200 spin_unlock(&con->writequeue_lock); 1201 1202 if (e) { 1203 got_one: 1204 if (users == 0) 1205 kmap(e->page); 1206 *ppc = page_address(e->page) + offset; 1207 return e; 1208 } 1209 1210 e = new_writequeue_entry(con, allocation); 1211 if (e) { 1212 spin_lock(&con->writequeue_lock); 1213 offset = e->end; 1214 e->end += len; 1215 users = e->users++; 1216 list_add_tail(&e->list, &con->writequeue); 1217 spin_unlock(&con->writequeue_lock); 1218 goto got_one; 1219 } 1220 return NULL; 1221} 1222 1223void dlm_lowcomms_commit_buffer(void *mh) 1224{ 1225 struct writequeue_entry *e = (struct writequeue_entry *)mh; 1226 struct connection *con = e->con; 1227 int users; 1228 1229 spin_lock(&con->writequeue_lock); 1230 users = --e->users; 1231 if (users) 1232 goto out; 1233 e->len = e->end - e->offset; 1234 kunmap(e->page); 1235 spin_unlock(&con->writequeue_lock); 1236 1237 if (!test_and_set_bit(CF_WRITE_PENDING, &con->flags)) { 1238 queue_work(send_workqueue, &con->swork); 1239 } 1240 return; 1241 1242out: 1243 spin_unlock(&con->writequeue_lock); 1244 return; 1245} 1246 1247/* Send a message */ 1248static void send_to_sock(struct connection *con) 1249{ 1250 int ret = 0; 1251 ssize_t(*sendpage) (struct socket *, struct page *, int, size_t, int); 1252 const int msg_flags = MSG_DONTWAIT | MSG_NOSIGNAL; 1253 struct writequeue_entry *e; 1254 int len, offset; 1255 1256 mutex_lock(&con->sock_mutex); 1257 if (con->sock == NULL) 1258 goto out_connect; 1259 1260 sendpage = con->sock->ops->sendpage; 1261 1262 spin_lock(&con->writequeue_lock); 1263 for (;;) { 1264 e = list_entry(con->writequeue.next, struct writequeue_entry, 1265 list); 1266 if ((struct list_head *) e == &con->writequeue) 1267 break; 1268 1269 len = e->len; 1270 offset = e->offset; 1271 BUG_ON(len == 0 && e->users == 0); 1272 spin_unlock(&con->writequeue_lock); 1273 kmap(e->page); 1274 1275 ret = 0; 1276 if (len) { 1277 ret = sendpage(con->sock, e->page, offset, len, 1278 msg_flags); 1279 if (ret == -EAGAIN || ret == 0) { 1280 cond_resched(); 1281 goto out; 1282 } 1283 if (ret <= 0) 1284 goto send_error; 1285 } 1286 /* Don't starve people filling buffers */ 1287 cond_resched(); 1288 1289 spin_lock(&con->writequeue_lock); 1290 e->offset += ret; 1291 e->len -= ret; 1292 1293 if (e->len == 0 && e->users == 0) { 1294 list_del(&e->list); 1295 kunmap(e->page); 1296 free_entry(e); 1297 continue; 1298 } 1299 } 1300 spin_unlock(&con->writequeue_lock); 1301out: 1302 mutex_unlock(&con->sock_mutex); 1303 return; 1304 1305send_error: 1306 mutex_unlock(&con->sock_mutex); 1307 close_connection(con, false); 1308 lowcomms_connect_sock(con); 1309 return; 1310 1311out_connect: 1312 mutex_unlock(&con->sock_mutex); 1313 if (!test_bit(CF_INIT_PENDING, &con->flags)) 1314 lowcomms_connect_sock(con); 1315 return; 1316} 1317 1318static void clean_one_writequeue(struct connection *con) 1319{ 1320 struct list_head *list; 1321 struct list_head *temp; 1322 1323 spin_lock(&con->writequeue_lock); 1324 list_for_each_safe(list, temp, &con->writequeue) { 1325 struct writequeue_entry *e = 1326 list_entry(list, struct writequeue_entry, list); 1327 list_del(&e->list); 1328 free_entry(e); 1329 } 1330 spin_unlock(&con->writequeue_lock); 1331} 1332 1333/* Called from recovery when it knows that a node has 1334 left the cluster */ 1335int dlm_lowcomms_close(int nodeid) 1336{ 1337 struct connection *con; 1338 1339 log_print("closing connection to node %d", nodeid); 1340 con = nodeid2con(nodeid, 0); 1341 if (con) { 1342 clean_one_writequeue(con); 1343 close_connection(con, true); 1344 } 1345 return 0; 1346} 1347 1348/* Receive workqueue function */ 1349static void process_recv_sockets(struct work_struct *work) 1350{ 1351 struct connection *con = container_of(work, struct connection, rwork); 1352 int err; 1353 1354 clear_bit(CF_READ_PENDING, &con->flags); 1355 do { 1356 err = con->rx_action(con); 1357 } while (!err); 1358} 1359 1360/* Send workqueue function */ 1361static void process_send_sockets(struct work_struct *work) 1362{ 1363 struct connection *con = container_of(work, struct connection, swork); 1364 1365 if (test_and_clear_bit(CF_CONNECT_PENDING, &con->flags)) { 1366 con->connect_action(con); 1367 } 1368 clear_bit(CF_WRITE_PENDING, &con->flags); 1369 send_to_sock(con); 1370} 1371 1372 1373/* Discard all entries on the write queues */ 1374static void clean_writequeues(void) 1375{ 1376 int nodeid; 1377 1378 for (nodeid = 1; nodeid <= max_nodeid; nodeid++) { 1379 struct connection *con = __nodeid2con(nodeid, 0); 1380 1381 if (con) 1382 clean_one_writequeue(con); 1383 } 1384} 1385 1386static void work_stop(void) 1387{ 1388 destroy_workqueue(recv_workqueue); 1389 destroy_workqueue(send_workqueue); 1390} 1391 1392static int work_start(void) 1393{ 1394 int error; 1395 recv_workqueue = create_workqueue("dlm_recv"); 1396 error = IS_ERR(recv_workqueue); 1397 if (error) { 1398 log_print("can't start dlm_recv %d", error); 1399 return error; 1400 } 1401 1402 send_workqueue = create_singlethread_workqueue("dlm_send"); 1403 error = IS_ERR(send_workqueue); 1404 if (error) { 1405 log_print("can't start dlm_send %d", error); 1406 destroy_workqueue(recv_workqueue); 1407 return error; 1408 } 1409 1410 return 0; 1411} 1412 1413void dlm_lowcomms_stop(void) 1414{ 1415 int i; 1416 struct connection *con; 1417 1418 /* Set all the flags to prevent any 1419 socket activity. 1420 */ 1421 mutex_lock(&connections_lock); 1422 for (i = 0; i <= max_nodeid; i++) { 1423 con = __nodeid2con(i, 0); 1424 if (con) { 1425 con->flags |= 0x0F; 1426 if (con->sock) 1427 con->sock->sk->sk_user_data = NULL; 1428 } 1429 } 1430 mutex_unlock(&connections_lock); 1431 1432 work_stop(); 1433 1434 mutex_lock(&connections_lock); 1435 clean_writequeues(); 1436 1437 for (i = 0; i <= max_nodeid; i++) { 1438 con = __nodeid2con(i, 0); 1439 if (con) { 1440 close_connection(con, true); 1441 if (con->othercon) 1442 kmem_cache_free(con_cache, con->othercon); 1443 kmem_cache_free(con_cache, con); 1444 } 1445 } 1446 max_nodeid = 0; 1447 mutex_unlock(&connections_lock); 1448 kmem_cache_destroy(con_cache); 1449 idr_init(&connections_idr); 1450} 1451 1452int dlm_lowcomms_start(void) 1453{ 1454 int error = -EINVAL; 1455 struct connection *con; 1456 1457 init_local(); 1458 if (!dlm_local_count) { 1459 error = -ENOTCONN; 1460 log_print("no local IP address has been set"); 1461 goto out; 1462 } 1463 1464 error = -ENOMEM; 1465 con_cache = kmem_cache_create("dlm_conn", sizeof(struct connection), 1466 __alignof__(struct connection), 0, 1467 NULL); 1468 if (!con_cache) 1469 goto out; 1470 1471 /* Start listening */ 1472 if (dlm_config.ci_protocol == 0) 1473 error = tcp_listen_for_all(); 1474 else 1475 error = sctp_listen_for_all(); 1476 if (error) 1477 goto fail_unlisten; 1478 1479 error = work_start(); 1480 if (error) 1481 goto fail_unlisten; 1482 1483 return 0; 1484 1485fail_unlisten: 1486 con = nodeid2con(0,0); 1487 if (con) { 1488 close_connection(con, false); 1489 kmem_cache_free(con_cache, con); 1490 } 1491 kmem_cache_destroy(con_cache); 1492 1493out: 1494 return error; 1495} 1496