1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * 4 * Copyright (C) 2004 Oracle. All rights reserved. 5 * 6 * ---- 7 * 8 * Callers for this were originally written against a very simple synchronus 9 * API. This implementation reflects those simple callers. Some day I'm sure 10 * we'll need to move to a more robust posting/callback mechanism. 11 * 12 * Transmit calls pass in kernel virtual addresses and block copying this into 13 * the socket's tx buffers via a usual blocking sendmsg. They'll block waiting 14 * for a failed socket to timeout. TX callers can also pass in a poniter to an 15 * 'int' which gets filled with an errno off the wire in response to the 16 * message they send. 17 * 18 * Handlers for unsolicited messages are registered. Each socket has a page 19 * that incoming data is copied into. First the header, then the data. 20 * Handlers are called from only one thread with a reference to this per-socket 21 * page. This page is destroyed after the handler call, so it can't be 22 * referenced beyond the call. Handlers may block but are discouraged from 23 * doing so. 24 * 25 * Any framing errors (bad magic, large payload lengths) close a connection. 26 * 27 * Our sock_container holds the state we associate with a socket. It's current 28 * framing state is held there as well as the refcounting we do around when it 29 * is safe to tear down the socket. The socket is only finally torn down from 30 * the container when the container loses all of its references -- so as long 31 * as you hold a ref on the container you can trust that the socket is valid 32 * for use with kernel socket APIs. 33 * 34 * Connections are initiated between a pair of nodes when the node with the 35 * higher node number gets a heartbeat callback which indicates that the lower 36 * numbered node has started heartbeating. The lower numbered node is passive 37 * and only accepts the connection if the higher numbered node is heartbeating. 38 */ 39 40#include <linux/kernel.h> 41#include <linux/sched/mm.h> 42#include <linux/jiffies.h> 43#include <linux/slab.h> 44#include <linux/idr.h> 45#include <linux/kref.h> 46#include <linux/net.h> 47#include <linux/export.h> 48#include <net/tcp.h> 49#include <trace/events/sock.h> 50 51#include <linux/uaccess.h> 52 53#include "heartbeat.h" 54#include "tcp.h" 55#include "nodemanager.h" 56#define MLOG_MASK_PREFIX ML_TCP 57#include "masklog.h" 58#include "quorum.h" 59 60#include "tcp_internal.h" 61 62#define SC_NODEF_FMT "node %s (num %u) at %pI4:%u" 63#define SC_NODEF_ARGS(sc) sc->sc_node->nd_name, sc->sc_node->nd_num, \ 64 &sc->sc_node->nd_ipv4_address, \ 65 ntohs(sc->sc_node->nd_ipv4_port) 66 67/* 68 * In the following two log macros, the whitespace after the ',' just 69 * before ##args is intentional. Otherwise, gcc 2.95 will eat the 70 * previous token if args expands to nothing. 71 */ 72#define msglog(hdr, fmt, args...) do { \ 73 typeof(hdr) __hdr = (hdr); \ 74 mlog(ML_MSG, "[mag %u len %u typ %u stat %d sys_stat %d " \ 75 "key %08x num %u] " fmt, \ 76 be16_to_cpu(__hdr->magic), be16_to_cpu(__hdr->data_len), \ 77 be16_to_cpu(__hdr->msg_type), be32_to_cpu(__hdr->status), \ 78 be32_to_cpu(__hdr->sys_status), be32_to_cpu(__hdr->key), \ 79 be32_to_cpu(__hdr->msg_num) , ##args); \ 80} while (0) 81 82#define sclog(sc, fmt, args...) do { \ 83 typeof(sc) __sc = (sc); \ 84 mlog(ML_SOCKET, "[sc %p refs %d sock %p node %u page %p " \ 85 "pg_off %zu] " fmt, __sc, \ 86 kref_read(&__sc->sc_kref), __sc->sc_sock, \ 87 __sc->sc_node->nd_num, __sc->sc_page, __sc->sc_page_off , \ 88 ##args); \ 89} while (0) 90 91static DEFINE_RWLOCK(o2net_handler_lock); 92static struct rb_root o2net_handler_tree = RB_ROOT; 93 94static struct o2net_node o2net_nodes[O2NM_MAX_NODES]; 95 96/* XXX someday we'll need better accounting */ 97static struct socket *o2net_listen_sock; 98 99/* 100 * listen work is only queued by the listening socket callbacks on the 101 * o2net_wq. teardown detaches the callbacks before destroying the workqueue. 102 * quorum work is queued as sock containers are shutdown.. stop_listening 103 * tears down all the node's sock containers, preventing future shutdowns 104 * and queued quroum work, before canceling delayed quorum work and 105 * destroying the work queue. 106 */ 107static struct workqueue_struct *o2net_wq; 108static struct work_struct o2net_listen_work; 109 110static struct o2hb_callback_func o2net_hb_up, o2net_hb_down; 111#define O2NET_HB_PRI 0x1 112 113static struct o2net_handshake *o2net_hand; 114static struct o2net_msg *o2net_keep_req, *o2net_keep_resp; 115 116static int o2net_sys_err_translations[O2NET_ERR_MAX] = 117 {[O2NET_ERR_NONE] = 0, 118 [O2NET_ERR_NO_HNDLR] = -ENOPROTOOPT, 119 [O2NET_ERR_OVERFLOW] = -EOVERFLOW, 120 [O2NET_ERR_DIED] = -EHOSTDOWN,}; 121 122/* can't quite avoid *all* internal declarations :/ */ 123static void o2net_sc_connect_completed(struct work_struct *work); 124static void o2net_rx_until_empty(struct work_struct *work); 125static void o2net_shutdown_sc(struct work_struct *work); 126static void o2net_listen_data_ready(struct sock *sk); 127static void o2net_sc_send_keep_req(struct work_struct *work); 128static void o2net_idle_timer(struct timer_list *t); 129static void o2net_sc_postpone_idle(struct o2net_sock_container *sc); 130static void o2net_sc_reset_idle_timer(struct o2net_sock_container *sc); 131 132#ifdef CONFIG_DEBUG_FS 133static void o2net_init_nst(struct o2net_send_tracking *nst, u32 msgtype, 134 u32 msgkey, struct task_struct *task, u8 node) 135{ 136 INIT_LIST_HEAD(&nst->st_net_debug_item); 137 nst->st_task = task; 138 nst->st_msg_type = msgtype; 139 nst->st_msg_key = msgkey; 140 nst->st_node = node; 141} 142 143static inline void o2net_set_nst_sock_time(struct o2net_send_tracking *nst) 144{ 145 nst->st_sock_time = ktime_get(); 146} 147 148static inline void o2net_set_nst_send_time(struct o2net_send_tracking *nst) 149{ 150 nst->st_send_time = ktime_get(); 151} 152 153static inline void o2net_set_nst_status_time(struct o2net_send_tracking *nst) 154{ 155 nst->st_status_time = ktime_get(); 156} 157 158static inline void o2net_set_nst_sock_container(struct o2net_send_tracking *nst, 159 struct o2net_sock_container *sc) 160{ 161 nst->st_sc = sc; 162} 163 164static inline void o2net_set_nst_msg_id(struct o2net_send_tracking *nst, 165 u32 msg_id) 166{ 167 nst->st_id = msg_id; 168} 169 170static inline void o2net_set_sock_timer(struct o2net_sock_container *sc) 171{ 172 sc->sc_tv_timer = ktime_get(); 173} 174 175static inline void o2net_set_data_ready_time(struct o2net_sock_container *sc) 176{ 177 sc->sc_tv_data_ready = ktime_get(); 178} 179 180static inline void o2net_set_advance_start_time(struct o2net_sock_container *sc) 181{ 182 sc->sc_tv_advance_start = ktime_get(); 183} 184 185static inline void o2net_set_advance_stop_time(struct o2net_sock_container *sc) 186{ 187 sc->sc_tv_advance_stop = ktime_get(); 188} 189 190static inline void o2net_set_func_start_time(struct o2net_sock_container *sc) 191{ 192 sc->sc_tv_func_start = ktime_get(); 193} 194 195static inline void o2net_set_func_stop_time(struct o2net_sock_container *sc) 196{ 197 sc->sc_tv_func_stop = ktime_get(); 198} 199 200#else /* CONFIG_DEBUG_FS */ 201# define o2net_init_nst(a, b, c, d, e) 202# define o2net_set_nst_sock_time(a) 203# define o2net_set_nst_send_time(a) 204# define o2net_set_nst_status_time(a) 205# define o2net_set_nst_sock_container(a, b) 206# define o2net_set_nst_msg_id(a, b) 207# define o2net_set_sock_timer(a) 208# define o2net_set_data_ready_time(a) 209# define o2net_set_advance_start_time(a) 210# define o2net_set_advance_stop_time(a) 211# define o2net_set_func_start_time(a) 212# define o2net_set_func_stop_time(a) 213#endif /* CONFIG_DEBUG_FS */ 214 215#ifdef CONFIG_OCFS2_FS_STATS 216static ktime_t o2net_get_func_run_time(struct o2net_sock_container *sc) 217{ 218 return ktime_sub(sc->sc_tv_func_stop, sc->sc_tv_func_start); 219} 220 221static void o2net_update_send_stats(struct o2net_send_tracking *nst, 222 struct o2net_sock_container *sc) 223{ 224 sc->sc_tv_status_total = ktime_add(sc->sc_tv_status_total, 225 ktime_sub(ktime_get(), 226 nst->st_status_time)); 227 sc->sc_tv_send_total = ktime_add(sc->sc_tv_send_total, 228 ktime_sub(nst->st_status_time, 229 nst->st_send_time)); 230 sc->sc_tv_acquiry_total = ktime_add(sc->sc_tv_acquiry_total, 231 ktime_sub(nst->st_send_time, 232 nst->st_sock_time)); 233 sc->sc_send_count++; 234} 235 236static void o2net_update_recv_stats(struct o2net_sock_container *sc) 237{ 238 sc->sc_tv_process_total = ktime_add(sc->sc_tv_process_total, 239 o2net_get_func_run_time(sc)); 240 sc->sc_recv_count++; 241} 242 243#else 244 245# define o2net_update_send_stats(a, b) 246 247# define o2net_update_recv_stats(sc) 248 249#endif /* CONFIG_OCFS2_FS_STATS */ 250 251static inline unsigned int o2net_reconnect_delay(void) 252{ 253 return o2nm_single_cluster->cl_reconnect_delay_ms; 254} 255 256static inline unsigned int o2net_keepalive_delay(void) 257{ 258 return o2nm_single_cluster->cl_keepalive_delay_ms; 259} 260 261static inline unsigned int o2net_idle_timeout(void) 262{ 263 return o2nm_single_cluster->cl_idle_timeout_ms; 264} 265 266static inline int o2net_sys_err_to_errno(enum o2net_system_error err) 267{ 268 int trans; 269 BUG_ON(err >= O2NET_ERR_MAX); 270 trans = o2net_sys_err_translations[err]; 271 272 /* Just in case we mess up the translation table above */ 273 BUG_ON(err != O2NET_ERR_NONE && trans == 0); 274 return trans; 275} 276 277static struct o2net_node * o2net_nn_from_num(u8 node_num) 278{ 279 BUG_ON(node_num >= ARRAY_SIZE(o2net_nodes)); 280 return &o2net_nodes[node_num]; 281} 282 283static u8 o2net_num_from_nn(struct o2net_node *nn) 284{ 285 BUG_ON(nn == NULL); 286 return nn - o2net_nodes; 287} 288 289/* ------------------------------------------------------------ */ 290 291static int o2net_prep_nsw(struct o2net_node *nn, struct o2net_status_wait *nsw) 292{ 293 int ret; 294 295 spin_lock(&nn->nn_lock); 296 ret = idr_alloc(&nn->nn_status_idr, nsw, 0, 0, GFP_ATOMIC); 297 if (ret >= 0) { 298 nsw->ns_id = ret; 299 list_add_tail(&nsw->ns_node_item, &nn->nn_status_list); 300 } 301 spin_unlock(&nn->nn_lock); 302 if (ret < 0) 303 return ret; 304 305 init_waitqueue_head(&nsw->ns_wq); 306 nsw->ns_sys_status = O2NET_ERR_NONE; 307 nsw->ns_status = 0; 308 return 0; 309} 310 311static void o2net_complete_nsw_locked(struct o2net_node *nn, 312 struct o2net_status_wait *nsw, 313 enum o2net_system_error sys_status, 314 s32 status) 315{ 316 assert_spin_locked(&nn->nn_lock); 317 318 if (!list_empty(&nsw->ns_node_item)) { 319 list_del_init(&nsw->ns_node_item); 320 nsw->ns_sys_status = sys_status; 321 nsw->ns_status = status; 322 idr_remove(&nn->nn_status_idr, nsw->ns_id); 323 wake_up(&nsw->ns_wq); 324 } 325} 326 327static void o2net_complete_nsw(struct o2net_node *nn, 328 struct o2net_status_wait *nsw, 329 u64 id, enum o2net_system_error sys_status, 330 s32 status) 331{ 332 spin_lock(&nn->nn_lock); 333 if (nsw == NULL) { 334 if (id > INT_MAX) 335 goto out; 336 337 nsw = idr_find(&nn->nn_status_idr, id); 338 if (nsw == NULL) 339 goto out; 340 } 341 342 o2net_complete_nsw_locked(nn, nsw, sys_status, status); 343 344out: 345 spin_unlock(&nn->nn_lock); 346 return; 347} 348 349static void o2net_complete_nodes_nsw(struct o2net_node *nn) 350{ 351 struct o2net_status_wait *nsw, *tmp; 352 unsigned int num_kills = 0; 353 354 assert_spin_locked(&nn->nn_lock); 355 356 list_for_each_entry_safe(nsw, tmp, &nn->nn_status_list, ns_node_item) { 357 o2net_complete_nsw_locked(nn, nsw, O2NET_ERR_DIED, 0); 358 num_kills++; 359 } 360 361 mlog(0, "completed %d messages for node %u\n", num_kills, 362 o2net_num_from_nn(nn)); 363} 364 365static int o2net_nsw_completed(struct o2net_node *nn, 366 struct o2net_status_wait *nsw) 367{ 368 int completed; 369 spin_lock(&nn->nn_lock); 370 completed = list_empty(&nsw->ns_node_item); 371 spin_unlock(&nn->nn_lock); 372 return completed; 373} 374 375/* ------------------------------------------------------------ */ 376 377static void sc_kref_release(struct kref *kref) 378{ 379 struct o2net_sock_container *sc = container_of(kref, 380 struct o2net_sock_container, sc_kref); 381 BUG_ON(timer_pending(&sc->sc_idle_timeout)); 382 383 sclog(sc, "releasing\n"); 384 385 if (sc->sc_sock) { 386 sock_release(sc->sc_sock); 387 sc->sc_sock = NULL; 388 } 389 390 o2nm_undepend_item(&sc->sc_node->nd_item); 391 o2nm_node_put(sc->sc_node); 392 sc->sc_node = NULL; 393 394 o2net_debug_del_sc(sc); 395 396 if (sc->sc_page) 397 __free_page(sc->sc_page); 398 kfree(sc); 399} 400 401static void sc_put(struct o2net_sock_container *sc) 402{ 403 sclog(sc, "put\n"); 404 kref_put(&sc->sc_kref, sc_kref_release); 405} 406static void sc_get(struct o2net_sock_container *sc) 407{ 408 sclog(sc, "get\n"); 409 kref_get(&sc->sc_kref); 410} 411static struct o2net_sock_container *sc_alloc(struct o2nm_node *node) 412{ 413 struct o2net_sock_container *sc, *ret = NULL; 414 struct page *page = NULL; 415 int status = 0; 416 417 page = alloc_page(GFP_NOFS); 418 sc = kzalloc(sizeof(*sc), GFP_NOFS); 419 if (sc == NULL || page == NULL) 420 goto out; 421 422 kref_init(&sc->sc_kref); 423 o2nm_node_get(node); 424 sc->sc_node = node; 425 426 /* pin the node item of the remote node */ 427 status = o2nm_depend_item(&node->nd_item); 428 if (status) { 429 mlog_errno(status); 430 o2nm_node_put(node); 431 goto out; 432 } 433 INIT_WORK(&sc->sc_connect_work, o2net_sc_connect_completed); 434 INIT_WORK(&sc->sc_rx_work, o2net_rx_until_empty); 435 INIT_WORK(&sc->sc_shutdown_work, o2net_shutdown_sc); 436 INIT_DELAYED_WORK(&sc->sc_keepalive_work, o2net_sc_send_keep_req); 437 438 timer_setup(&sc->sc_idle_timeout, o2net_idle_timer, 0); 439 440 sclog(sc, "alloced\n"); 441 442 ret = sc; 443 sc->sc_page = page; 444 o2net_debug_add_sc(sc); 445 sc = NULL; 446 page = NULL; 447 448out: 449 if (page) 450 __free_page(page); 451 kfree(sc); 452 453 return ret; 454} 455 456/* ------------------------------------------------------------ */ 457 458static void o2net_sc_queue_work(struct o2net_sock_container *sc, 459 struct work_struct *work) 460{ 461 sc_get(sc); 462 if (!queue_work(o2net_wq, work)) 463 sc_put(sc); 464} 465static void o2net_sc_queue_delayed_work(struct o2net_sock_container *sc, 466 struct delayed_work *work, 467 int delay) 468{ 469 sc_get(sc); 470 if (!queue_delayed_work(o2net_wq, work, delay)) 471 sc_put(sc); 472} 473static void o2net_sc_cancel_delayed_work(struct o2net_sock_container *sc, 474 struct delayed_work *work) 475{ 476 if (cancel_delayed_work(work)) 477 sc_put(sc); 478} 479 480static atomic_t o2net_connected_peers = ATOMIC_INIT(0); 481 482int o2net_num_connected_peers(void) 483{ 484 return atomic_read(&o2net_connected_peers); 485} 486 487static void o2net_set_nn_state(struct o2net_node *nn, 488 struct o2net_sock_container *sc, 489 unsigned valid, int err) 490{ 491 int was_valid = nn->nn_sc_valid; 492 int was_err = nn->nn_persistent_error; 493 struct o2net_sock_container *old_sc = nn->nn_sc; 494 495 assert_spin_locked(&nn->nn_lock); 496 497 if (old_sc && !sc) 498 atomic_dec(&o2net_connected_peers); 499 else if (!old_sc && sc) 500 atomic_inc(&o2net_connected_peers); 501 502 /* the node num comparison and single connect/accept path should stop 503 * an non-null sc from being overwritten with another */ 504 BUG_ON(sc && nn->nn_sc && nn->nn_sc != sc); 505 mlog_bug_on_msg(err && valid, "err %d valid %u\n", err, valid); 506 mlog_bug_on_msg(valid && !sc, "valid %u sc %p\n", valid, sc); 507 508 if (was_valid && !valid && err == 0) 509 err = -ENOTCONN; 510 511 mlog(ML_CONN, "node %u sc: %p -> %p, valid %u -> %u, err %d -> %d\n", 512 o2net_num_from_nn(nn), nn->nn_sc, sc, nn->nn_sc_valid, valid, 513 nn->nn_persistent_error, err); 514 515 nn->nn_sc = sc; 516 nn->nn_sc_valid = valid ? 1 : 0; 517 nn->nn_persistent_error = err; 518 519 /* mirrors o2net_tx_can_proceed() */ 520 if (nn->nn_persistent_error || nn->nn_sc_valid) 521 wake_up(&nn->nn_sc_wq); 522 523 if (was_valid && !was_err && nn->nn_persistent_error) { 524 o2quo_conn_err(o2net_num_from_nn(nn)); 525 queue_delayed_work(o2net_wq, &nn->nn_still_up, 526 msecs_to_jiffies(O2NET_QUORUM_DELAY_MS)); 527 } 528 529 if (was_valid && !valid) { 530 if (old_sc) 531 printk(KERN_NOTICE "o2net: No longer connected to " 532 SC_NODEF_FMT "\n", SC_NODEF_ARGS(old_sc)); 533 o2net_complete_nodes_nsw(nn); 534 } 535 536 if (!was_valid && valid) { 537 o2quo_conn_up(o2net_num_from_nn(nn)); 538 cancel_delayed_work(&nn->nn_connect_expired); 539 printk(KERN_NOTICE "o2net: %s " SC_NODEF_FMT "\n", 540 o2nm_this_node() > sc->sc_node->nd_num ? 541 "Connected to" : "Accepted connection from", 542 SC_NODEF_ARGS(sc)); 543 } 544 545 /* trigger the connecting worker func as long as we're not valid, 546 * it will back off if it shouldn't connect. This can be called 547 * from node config teardown and so needs to be careful about 548 * the work queue actually being up. */ 549 if (!valid && o2net_wq) { 550 unsigned long delay; 551 /* delay if we're within a RECONNECT_DELAY of the 552 * last attempt */ 553 delay = (nn->nn_last_connect_attempt + 554 msecs_to_jiffies(o2net_reconnect_delay())) 555 - jiffies; 556 if (delay > msecs_to_jiffies(o2net_reconnect_delay())) 557 delay = 0; 558 mlog(ML_CONN, "queueing conn attempt in %lu jiffies\n", delay); 559 queue_delayed_work(o2net_wq, &nn->nn_connect_work, delay); 560 561 /* 562 * Delay the expired work after idle timeout. 563 * 564 * We might have lots of failed connection attempts that run 565 * through here but we only cancel the connect_expired work when 566 * a connection attempt succeeds. So only the first enqueue of 567 * the connect_expired work will do anything. The rest will see 568 * that it's already queued and do nothing. 569 */ 570 delay += msecs_to_jiffies(o2net_idle_timeout()); 571 queue_delayed_work(o2net_wq, &nn->nn_connect_expired, delay); 572 } 573 574 /* keep track of the nn's sc ref for the caller */ 575 if ((old_sc == NULL) && sc) 576 sc_get(sc); 577 if (old_sc && (old_sc != sc)) { 578 o2net_sc_queue_work(old_sc, &old_sc->sc_shutdown_work); 579 sc_put(old_sc); 580 } 581} 582 583/* see o2net_register_callbacks() */ 584static void o2net_data_ready(struct sock *sk) 585{ 586 void (*ready)(struct sock *sk); 587 struct o2net_sock_container *sc; 588 589 trace_sk_data_ready(sk); 590 591 read_lock_bh(&sk->sk_callback_lock); 592 sc = sk->sk_user_data; 593 if (sc) { 594 sclog(sc, "data_ready hit\n"); 595 o2net_set_data_ready_time(sc); 596 o2net_sc_queue_work(sc, &sc->sc_rx_work); 597 ready = sc->sc_data_ready; 598 } else { 599 ready = sk->sk_data_ready; 600 } 601 read_unlock_bh(&sk->sk_callback_lock); 602 603 ready(sk); 604} 605 606/* see o2net_register_callbacks() */ 607static void o2net_state_change(struct sock *sk) 608{ 609 void (*state_change)(struct sock *sk); 610 struct o2net_sock_container *sc; 611 612 read_lock_bh(&sk->sk_callback_lock); 613 sc = sk->sk_user_data; 614 if (sc == NULL) { 615 state_change = sk->sk_state_change; 616 goto out; 617 } 618 619 sclog(sc, "state_change to %d\n", sk->sk_state); 620 621 state_change = sc->sc_state_change; 622 623 switch(sk->sk_state) { 624 /* ignore connecting sockets as they make progress */ 625 case TCP_SYN_SENT: 626 case TCP_SYN_RECV: 627 break; 628 case TCP_ESTABLISHED: 629 o2net_sc_queue_work(sc, &sc->sc_connect_work); 630 break; 631 default: 632 printk(KERN_INFO "o2net: Connection to " SC_NODEF_FMT 633 " shutdown, state %d\n", 634 SC_NODEF_ARGS(sc), sk->sk_state); 635 o2net_sc_queue_work(sc, &sc->sc_shutdown_work); 636 break; 637 } 638out: 639 read_unlock_bh(&sk->sk_callback_lock); 640 state_change(sk); 641} 642 643/* 644 * we register callbacks so we can queue work on events before calling 645 * the original callbacks. our callbacks our careful to test user_data 646 * to discover when they've reaced with o2net_unregister_callbacks(). 647 */ 648static void o2net_register_callbacks(struct sock *sk, 649 struct o2net_sock_container *sc) 650{ 651 write_lock_bh(&sk->sk_callback_lock); 652 653 /* accepted sockets inherit the old listen socket data ready */ 654 if (sk->sk_data_ready == o2net_listen_data_ready) { 655 sk->sk_data_ready = sk->sk_user_data; 656 sk->sk_user_data = NULL; 657 } 658 659 BUG_ON(sk->sk_user_data != NULL); 660 sk->sk_user_data = sc; 661 sc_get(sc); 662 663 sc->sc_data_ready = sk->sk_data_ready; 664 sc->sc_state_change = sk->sk_state_change; 665 sk->sk_data_ready = o2net_data_ready; 666 sk->sk_state_change = o2net_state_change; 667 668 mutex_init(&sc->sc_send_lock); 669 670 write_unlock_bh(&sk->sk_callback_lock); 671} 672 673static int o2net_unregister_callbacks(struct sock *sk, 674 struct o2net_sock_container *sc) 675{ 676 int ret = 0; 677 678 write_lock_bh(&sk->sk_callback_lock); 679 if (sk->sk_user_data == sc) { 680 ret = 1; 681 sk->sk_user_data = NULL; 682 sk->sk_data_ready = sc->sc_data_ready; 683 sk->sk_state_change = sc->sc_state_change; 684 } 685 write_unlock_bh(&sk->sk_callback_lock); 686 687 return ret; 688} 689 690/* 691 * this is a little helper that is called by callers who have seen a problem 692 * with an sc and want to detach it from the nn if someone already hasn't beat 693 * them to it. if an error is given then the shutdown will be persistent 694 * and pending transmits will be canceled. 695 */ 696static void o2net_ensure_shutdown(struct o2net_node *nn, 697 struct o2net_sock_container *sc, 698 int err) 699{ 700 spin_lock(&nn->nn_lock); 701 if (nn->nn_sc == sc) 702 o2net_set_nn_state(nn, NULL, 0, err); 703 spin_unlock(&nn->nn_lock); 704} 705 706/* 707 * This work queue function performs the blocking parts of socket shutdown. A 708 * few paths lead here. set_nn_state will trigger this callback if it sees an 709 * sc detached from the nn. state_change will also trigger this callback 710 * directly when it sees errors. In that case we need to call set_nn_state 711 * ourselves as state_change couldn't get the nn_lock and call set_nn_state 712 * itself. 713 */ 714static void o2net_shutdown_sc(struct work_struct *work) 715{ 716 struct o2net_sock_container *sc = 717 container_of(work, struct o2net_sock_container, 718 sc_shutdown_work); 719 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); 720 721 sclog(sc, "shutting down\n"); 722 723 /* drop the callbacks ref and call shutdown only once */ 724 if (o2net_unregister_callbacks(sc->sc_sock->sk, sc)) { 725 /* we shouldn't flush as we're in the thread, the 726 * races with pending sc work structs are harmless */ 727 del_timer_sync(&sc->sc_idle_timeout); 728 o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work); 729 sc_put(sc); 730 kernel_sock_shutdown(sc->sc_sock, SHUT_RDWR); 731 } 732 733 /* not fatal so failed connects before the other guy has our 734 * heartbeat can be retried */ 735 o2net_ensure_shutdown(nn, sc, 0); 736 sc_put(sc); 737} 738 739/* ------------------------------------------------------------ */ 740 741static int o2net_handler_cmp(struct o2net_msg_handler *nmh, u32 msg_type, 742 u32 key) 743{ 744 int ret = memcmp(&nmh->nh_key, &key, sizeof(key)); 745 746 if (ret == 0) 747 ret = memcmp(&nmh->nh_msg_type, &msg_type, sizeof(msg_type)); 748 749 return ret; 750} 751 752static struct o2net_msg_handler * 753o2net_handler_tree_lookup(u32 msg_type, u32 key, struct rb_node ***ret_p, 754 struct rb_node **ret_parent) 755{ 756 struct rb_node **p = &o2net_handler_tree.rb_node; 757 struct rb_node *parent = NULL; 758 struct o2net_msg_handler *nmh, *ret = NULL; 759 int cmp; 760 761 while (*p) { 762 parent = *p; 763 nmh = rb_entry(parent, struct o2net_msg_handler, nh_node); 764 cmp = o2net_handler_cmp(nmh, msg_type, key); 765 766 if (cmp < 0) 767 p = &(*p)->rb_left; 768 else if (cmp > 0) 769 p = &(*p)->rb_right; 770 else { 771 ret = nmh; 772 break; 773 } 774 } 775 776 if (ret_p != NULL) 777 *ret_p = p; 778 if (ret_parent != NULL) 779 *ret_parent = parent; 780 781 return ret; 782} 783 784static void o2net_handler_kref_release(struct kref *kref) 785{ 786 struct o2net_msg_handler *nmh; 787 nmh = container_of(kref, struct o2net_msg_handler, nh_kref); 788 789 kfree(nmh); 790} 791 792static void o2net_handler_put(struct o2net_msg_handler *nmh) 793{ 794 kref_put(&nmh->nh_kref, o2net_handler_kref_release); 795} 796 797/* max_len is protection for the handler func. incoming messages won't 798 * be given to the handler if their payload is longer than the max. */ 799int o2net_register_handler(u32 msg_type, u32 key, u32 max_len, 800 o2net_msg_handler_func *func, void *data, 801 o2net_post_msg_handler_func *post_func, 802 struct list_head *unreg_list) 803{ 804 struct o2net_msg_handler *nmh = NULL; 805 struct rb_node **p, *parent; 806 int ret = 0; 807 808 if (max_len > O2NET_MAX_PAYLOAD_BYTES) { 809 mlog(0, "max_len for message handler out of range: %u\n", 810 max_len); 811 ret = -EINVAL; 812 goto out; 813 } 814 815 if (!msg_type) { 816 mlog(0, "no message type provided: %u, %p\n", msg_type, func); 817 ret = -EINVAL; 818 goto out; 819 820 } 821 if (!func) { 822 mlog(0, "no message handler provided: %u, %p\n", 823 msg_type, func); 824 ret = -EINVAL; 825 goto out; 826 } 827 828 nmh = kzalloc(sizeof(struct o2net_msg_handler), GFP_NOFS); 829 if (nmh == NULL) { 830 ret = -ENOMEM; 831 goto out; 832 } 833 834 nmh->nh_func = func; 835 nmh->nh_func_data = data; 836 nmh->nh_post_func = post_func; 837 nmh->nh_msg_type = msg_type; 838 nmh->nh_max_len = max_len; 839 nmh->nh_key = key; 840 /* the tree and list get this ref.. they're both removed in 841 * unregister when this ref is dropped */ 842 kref_init(&nmh->nh_kref); 843 INIT_LIST_HEAD(&nmh->nh_unregister_item); 844 845 write_lock(&o2net_handler_lock); 846 if (o2net_handler_tree_lookup(msg_type, key, &p, &parent)) 847 ret = -EEXIST; 848 else { 849 rb_link_node(&nmh->nh_node, parent, p); 850 rb_insert_color(&nmh->nh_node, &o2net_handler_tree); 851 list_add_tail(&nmh->nh_unregister_item, unreg_list); 852 853 mlog(ML_TCP, "registered handler func %p type %u key %08x\n", 854 func, msg_type, key); 855 /* we've had some trouble with handlers seemingly vanishing. */ 856 mlog_bug_on_msg(o2net_handler_tree_lookup(msg_type, key, &p, 857 &parent) == NULL, 858 "couldn't find handler we *just* registered " 859 "for type %u key %08x\n", msg_type, key); 860 } 861 write_unlock(&o2net_handler_lock); 862 863out: 864 if (ret) 865 kfree(nmh); 866 867 return ret; 868} 869EXPORT_SYMBOL_GPL(o2net_register_handler); 870 871void o2net_unregister_handler_list(struct list_head *list) 872{ 873 struct o2net_msg_handler *nmh, *n; 874 875 write_lock(&o2net_handler_lock); 876 list_for_each_entry_safe(nmh, n, list, nh_unregister_item) { 877 mlog(ML_TCP, "unregistering handler func %p type %u key %08x\n", 878 nmh->nh_func, nmh->nh_msg_type, nmh->nh_key); 879 rb_erase(&nmh->nh_node, &o2net_handler_tree); 880 list_del_init(&nmh->nh_unregister_item); 881 kref_put(&nmh->nh_kref, o2net_handler_kref_release); 882 } 883 write_unlock(&o2net_handler_lock); 884} 885EXPORT_SYMBOL_GPL(o2net_unregister_handler_list); 886 887static struct o2net_msg_handler *o2net_handler_get(u32 msg_type, u32 key) 888{ 889 struct o2net_msg_handler *nmh; 890 891 read_lock(&o2net_handler_lock); 892 nmh = o2net_handler_tree_lookup(msg_type, key, NULL, NULL); 893 if (nmh) 894 kref_get(&nmh->nh_kref); 895 read_unlock(&o2net_handler_lock); 896 897 return nmh; 898} 899 900/* ------------------------------------------------------------ */ 901 902static int o2net_recv_tcp_msg(struct socket *sock, void *data, size_t len) 903{ 904 struct kvec vec = { .iov_len = len, .iov_base = data, }; 905 struct msghdr msg = { .msg_flags = MSG_DONTWAIT, }; 906 iov_iter_kvec(&msg.msg_iter, ITER_DEST, &vec, 1, len); 907 return sock_recvmsg(sock, &msg, MSG_DONTWAIT); 908} 909 910static int o2net_send_tcp_msg(struct socket *sock, struct kvec *vec, 911 size_t veclen, size_t total) 912{ 913 int ret; 914 struct msghdr msg = {.msg_flags = 0,}; 915 916 if (sock == NULL) { 917 ret = -EINVAL; 918 goto out; 919 } 920 921 ret = kernel_sendmsg(sock, &msg, vec, veclen, total); 922 if (likely(ret == total)) 923 return 0; 924 mlog(ML_ERROR, "sendmsg returned %d instead of %zu\n", ret, total); 925 if (ret >= 0) 926 ret = -EPIPE; /* should be smarter, I bet */ 927out: 928 mlog(0, "returning error: %d\n", ret); 929 return ret; 930} 931 932static void o2net_sendpage(struct o2net_sock_container *sc, 933 void *virt, size_t size) 934{ 935 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); 936 struct msghdr msg = {}; 937 struct bio_vec bv; 938 ssize_t ret; 939 940 bvec_set_virt(&bv, virt, size); 941 iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bv, 1, size); 942 943 while (1) { 944 msg.msg_flags = MSG_DONTWAIT | MSG_SPLICE_PAGES; 945 mutex_lock(&sc->sc_send_lock); 946 ret = sock_sendmsg(sc->sc_sock, &msg); 947 mutex_unlock(&sc->sc_send_lock); 948 949 if (ret == size) 950 break; 951 if (ret == (ssize_t)-EAGAIN) { 952 mlog(0, "sendpage of size %zu to " SC_NODEF_FMT 953 " returned EAGAIN\n", size, SC_NODEF_ARGS(sc)); 954 cond_resched(); 955 continue; 956 } 957 mlog(ML_ERROR, "sendpage of size %zu to " SC_NODEF_FMT 958 " failed with %zd\n", size, SC_NODEF_ARGS(sc), ret); 959 o2net_ensure_shutdown(nn, sc, 0); 960 break; 961 } 962} 963 964static void o2net_init_msg(struct o2net_msg *msg, u16 data_len, u16 msg_type, u32 key) 965{ 966 memset(msg, 0, sizeof(struct o2net_msg)); 967 msg->magic = cpu_to_be16(O2NET_MSG_MAGIC); 968 msg->data_len = cpu_to_be16(data_len); 969 msg->msg_type = cpu_to_be16(msg_type); 970 msg->sys_status = cpu_to_be32(O2NET_ERR_NONE); 971 msg->status = 0; 972 msg->key = cpu_to_be32(key); 973} 974 975static int o2net_tx_can_proceed(struct o2net_node *nn, 976 struct o2net_sock_container **sc_ret, 977 int *error) 978{ 979 int ret = 0; 980 981 spin_lock(&nn->nn_lock); 982 if (nn->nn_persistent_error) { 983 ret = 1; 984 *sc_ret = NULL; 985 *error = nn->nn_persistent_error; 986 } else if (nn->nn_sc_valid) { 987 kref_get(&nn->nn_sc->sc_kref); 988 989 ret = 1; 990 *sc_ret = nn->nn_sc; 991 *error = 0; 992 } 993 spin_unlock(&nn->nn_lock); 994 995 return ret; 996} 997 998/* Get a map of all nodes to which this node is currently connected to */ 999void o2net_fill_node_map(unsigned long *map, unsigned int bits) 1000{ 1001 struct o2net_sock_container *sc; 1002 int node, ret; 1003 1004 bitmap_zero(map, bits); 1005 for (node = 0; node < O2NM_MAX_NODES; ++node) { 1006 if (!o2net_tx_can_proceed(o2net_nn_from_num(node), &sc, &ret)) 1007 continue; 1008 if (!ret) { 1009 set_bit(node, map); 1010 sc_put(sc); 1011 } 1012 } 1013} 1014EXPORT_SYMBOL_GPL(o2net_fill_node_map); 1015 1016int o2net_send_message_vec(u32 msg_type, u32 key, struct kvec *caller_vec, 1017 size_t caller_veclen, u8 target_node, int *status) 1018{ 1019 int ret = 0; 1020 struct o2net_msg *msg = NULL; 1021 size_t veclen, caller_bytes = 0; 1022 struct kvec *vec = NULL; 1023 struct o2net_sock_container *sc = NULL; 1024 struct o2net_node *nn = o2net_nn_from_num(target_node); 1025 struct o2net_status_wait nsw = { 1026 .ns_node_item = LIST_HEAD_INIT(nsw.ns_node_item), 1027 }; 1028 struct o2net_send_tracking nst; 1029 1030 o2net_init_nst(&nst, msg_type, key, current, target_node); 1031 1032 if (o2net_wq == NULL) { 1033 mlog(0, "attempt to tx without o2netd running\n"); 1034 ret = -ESRCH; 1035 goto out; 1036 } 1037 1038 if (caller_veclen == 0) { 1039 mlog(0, "bad kvec array length\n"); 1040 ret = -EINVAL; 1041 goto out; 1042 } 1043 1044 caller_bytes = iov_length((struct iovec *)caller_vec, caller_veclen); 1045 if (caller_bytes > O2NET_MAX_PAYLOAD_BYTES) { 1046 mlog(0, "total payload len %zu too large\n", caller_bytes); 1047 ret = -EINVAL; 1048 goto out; 1049 } 1050 1051 if (target_node == o2nm_this_node()) { 1052 ret = -ELOOP; 1053 goto out; 1054 } 1055 1056 o2net_debug_add_nst(&nst); 1057 1058 o2net_set_nst_sock_time(&nst); 1059 1060 wait_event(nn->nn_sc_wq, o2net_tx_can_proceed(nn, &sc, &ret)); 1061 if (ret) 1062 goto out; 1063 1064 o2net_set_nst_sock_container(&nst, sc); 1065 1066 veclen = caller_veclen + 1; 1067 vec = kmalloc_array(veclen, sizeof(struct kvec), GFP_ATOMIC); 1068 if (vec == NULL) { 1069 mlog(0, "failed to %zu element kvec!\n", veclen); 1070 ret = -ENOMEM; 1071 goto out; 1072 } 1073 1074 msg = kmalloc(sizeof(struct o2net_msg), GFP_ATOMIC); 1075 if (!msg) { 1076 mlog(0, "failed to allocate a o2net_msg!\n"); 1077 ret = -ENOMEM; 1078 goto out; 1079 } 1080 1081 o2net_init_msg(msg, caller_bytes, msg_type, key); 1082 1083 vec[0].iov_len = sizeof(struct o2net_msg); 1084 vec[0].iov_base = msg; 1085 memcpy(&vec[1], caller_vec, caller_veclen * sizeof(struct kvec)); 1086 1087 ret = o2net_prep_nsw(nn, &nsw); 1088 if (ret) 1089 goto out; 1090 1091 msg->msg_num = cpu_to_be32(nsw.ns_id); 1092 o2net_set_nst_msg_id(&nst, nsw.ns_id); 1093 1094 o2net_set_nst_send_time(&nst); 1095 1096 /* finally, convert the message header to network byte-order 1097 * and send */ 1098 mutex_lock(&sc->sc_send_lock); 1099 ret = o2net_send_tcp_msg(sc->sc_sock, vec, veclen, 1100 sizeof(struct o2net_msg) + caller_bytes); 1101 mutex_unlock(&sc->sc_send_lock); 1102 msglog(msg, "sending returned %d\n", ret); 1103 if (ret < 0) { 1104 mlog(0, "error returned from o2net_send_tcp_msg=%d\n", ret); 1105 goto out; 1106 } 1107 1108 /* wait on other node's handler */ 1109 o2net_set_nst_status_time(&nst); 1110 wait_event(nsw.ns_wq, o2net_nsw_completed(nn, &nsw)); 1111 1112 o2net_update_send_stats(&nst, sc); 1113 1114 /* Note that we avoid overwriting the callers status return 1115 * variable if a system error was reported on the other 1116 * side. Callers beware. */ 1117 ret = o2net_sys_err_to_errno(nsw.ns_sys_status); 1118 if (status && !ret) 1119 *status = nsw.ns_status; 1120 1121 mlog(0, "woken, returning system status %d, user status %d\n", 1122 ret, nsw.ns_status); 1123out: 1124 o2net_debug_del_nst(&nst); /* must be before dropping sc and node */ 1125 if (sc) 1126 sc_put(sc); 1127 kfree(vec); 1128 kfree(msg); 1129 o2net_complete_nsw(nn, &nsw, 0, 0, 0); 1130 return ret; 1131} 1132EXPORT_SYMBOL_GPL(o2net_send_message_vec); 1133 1134int o2net_send_message(u32 msg_type, u32 key, void *data, u32 len, 1135 u8 target_node, int *status) 1136{ 1137 struct kvec vec = { 1138 .iov_base = data, 1139 .iov_len = len, 1140 }; 1141 return o2net_send_message_vec(msg_type, key, &vec, 1, 1142 target_node, status); 1143} 1144EXPORT_SYMBOL_GPL(o2net_send_message); 1145 1146static int o2net_send_status_magic(struct socket *sock, struct o2net_msg *hdr, 1147 enum o2net_system_error syserr, int err) 1148{ 1149 struct kvec vec = { 1150 .iov_base = hdr, 1151 .iov_len = sizeof(struct o2net_msg), 1152 }; 1153 1154 BUG_ON(syserr >= O2NET_ERR_MAX); 1155 1156 /* leave other fields intact from the incoming message, msg_num 1157 * in particular */ 1158 hdr->sys_status = cpu_to_be32(syserr); 1159 hdr->status = cpu_to_be32(err); 1160 hdr->magic = cpu_to_be16(O2NET_MSG_STATUS_MAGIC); // twiddle the magic 1161 hdr->data_len = 0; 1162 1163 msglog(hdr, "about to send status magic %d\n", err); 1164 /* hdr has been in host byteorder this whole time */ 1165 return o2net_send_tcp_msg(sock, &vec, 1, sizeof(struct o2net_msg)); 1166} 1167 1168/* this returns -errno if the header was unknown or too large, etc. 1169 * after this is called the buffer us reused for the next message */ 1170static int o2net_process_message(struct o2net_sock_container *sc, 1171 struct o2net_msg *hdr) 1172{ 1173 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); 1174 int ret = 0, handler_status; 1175 enum o2net_system_error syserr; 1176 struct o2net_msg_handler *nmh = NULL; 1177 void *ret_data = NULL; 1178 1179 msglog(hdr, "processing message\n"); 1180 1181 o2net_sc_postpone_idle(sc); 1182 1183 switch(be16_to_cpu(hdr->magic)) { 1184 case O2NET_MSG_STATUS_MAGIC: 1185 /* special type for returning message status */ 1186 o2net_complete_nsw(nn, NULL, 1187 be32_to_cpu(hdr->msg_num), 1188 be32_to_cpu(hdr->sys_status), 1189 be32_to_cpu(hdr->status)); 1190 goto out; 1191 case O2NET_MSG_KEEP_REQ_MAGIC: 1192 o2net_sendpage(sc, o2net_keep_resp, 1193 sizeof(*o2net_keep_resp)); 1194 goto out; 1195 case O2NET_MSG_KEEP_RESP_MAGIC: 1196 goto out; 1197 case O2NET_MSG_MAGIC: 1198 break; 1199 default: 1200 msglog(hdr, "bad magic\n"); 1201 ret = -EINVAL; 1202 goto out; 1203 } 1204 1205 /* find a handler for it */ 1206 handler_status = 0; 1207 nmh = o2net_handler_get(be16_to_cpu(hdr->msg_type), 1208 be32_to_cpu(hdr->key)); 1209 if (!nmh) { 1210 mlog(ML_TCP, "couldn't find handler for type %u key %08x\n", 1211 be16_to_cpu(hdr->msg_type), be32_to_cpu(hdr->key)); 1212 syserr = O2NET_ERR_NO_HNDLR; 1213 goto out_respond; 1214 } 1215 1216 syserr = O2NET_ERR_NONE; 1217 1218 if (be16_to_cpu(hdr->data_len) > nmh->nh_max_len) 1219 syserr = O2NET_ERR_OVERFLOW; 1220 1221 if (syserr != O2NET_ERR_NONE) 1222 goto out_respond; 1223 1224 o2net_set_func_start_time(sc); 1225 sc->sc_msg_key = be32_to_cpu(hdr->key); 1226 sc->sc_msg_type = be16_to_cpu(hdr->msg_type); 1227 handler_status = (nmh->nh_func)(hdr, sizeof(struct o2net_msg) + 1228 be16_to_cpu(hdr->data_len), 1229 nmh->nh_func_data, &ret_data); 1230 o2net_set_func_stop_time(sc); 1231 1232 o2net_update_recv_stats(sc); 1233 1234out_respond: 1235 /* this destroys the hdr, so don't use it after this */ 1236 mutex_lock(&sc->sc_send_lock); 1237 ret = o2net_send_status_magic(sc->sc_sock, hdr, syserr, 1238 handler_status); 1239 mutex_unlock(&sc->sc_send_lock); 1240 hdr = NULL; 1241 mlog(0, "sending handler status %d, syserr %d returned %d\n", 1242 handler_status, syserr, ret); 1243 1244 if (nmh) { 1245 BUG_ON(ret_data != NULL && nmh->nh_post_func == NULL); 1246 if (nmh->nh_post_func) 1247 (nmh->nh_post_func)(handler_status, nmh->nh_func_data, 1248 ret_data); 1249 } 1250 1251out: 1252 if (nmh) 1253 o2net_handler_put(nmh); 1254 return ret; 1255} 1256 1257static int o2net_check_handshake(struct o2net_sock_container *sc) 1258{ 1259 struct o2net_handshake *hand = page_address(sc->sc_page); 1260 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); 1261 1262 if (hand->protocol_version != cpu_to_be64(O2NET_PROTOCOL_VERSION)) { 1263 printk(KERN_NOTICE "o2net: " SC_NODEF_FMT " Advertised net " 1264 "protocol version %llu but %llu is required. " 1265 "Disconnecting.\n", SC_NODEF_ARGS(sc), 1266 (unsigned long long)be64_to_cpu(hand->protocol_version), 1267 O2NET_PROTOCOL_VERSION); 1268 1269 /* don't bother reconnecting if its the wrong version. */ 1270 o2net_ensure_shutdown(nn, sc, -ENOTCONN); 1271 return -1; 1272 } 1273 1274 /* 1275 * Ensure timeouts are consistent with other nodes, otherwise 1276 * we can end up with one node thinking that the other must be down, 1277 * but isn't. This can ultimately cause corruption. 1278 */ 1279 if (be32_to_cpu(hand->o2net_idle_timeout_ms) != 1280 o2net_idle_timeout()) { 1281 printk(KERN_NOTICE "o2net: " SC_NODEF_FMT " uses a network " 1282 "idle timeout of %u ms, but we use %u ms locally. " 1283 "Disconnecting.\n", SC_NODEF_ARGS(sc), 1284 be32_to_cpu(hand->o2net_idle_timeout_ms), 1285 o2net_idle_timeout()); 1286 o2net_ensure_shutdown(nn, sc, -ENOTCONN); 1287 return -1; 1288 } 1289 1290 if (be32_to_cpu(hand->o2net_keepalive_delay_ms) != 1291 o2net_keepalive_delay()) { 1292 printk(KERN_NOTICE "o2net: " SC_NODEF_FMT " uses a keepalive " 1293 "delay of %u ms, but we use %u ms locally. " 1294 "Disconnecting.\n", SC_NODEF_ARGS(sc), 1295 be32_to_cpu(hand->o2net_keepalive_delay_ms), 1296 o2net_keepalive_delay()); 1297 o2net_ensure_shutdown(nn, sc, -ENOTCONN); 1298 return -1; 1299 } 1300 1301 if (be32_to_cpu(hand->o2hb_heartbeat_timeout_ms) != 1302 O2HB_MAX_WRITE_TIMEOUT_MS) { 1303 printk(KERN_NOTICE "o2net: " SC_NODEF_FMT " uses a heartbeat " 1304 "timeout of %u ms, but we use %u ms locally. " 1305 "Disconnecting.\n", SC_NODEF_ARGS(sc), 1306 be32_to_cpu(hand->o2hb_heartbeat_timeout_ms), 1307 O2HB_MAX_WRITE_TIMEOUT_MS); 1308 o2net_ensure_shutdown(nn, sc, -ENOTCONN); 1309 return -1; 1310 } 1311 1312 sc->sc_handshake_ok = 1; 1313 1314 spin_lock(&nn->nn_lock); 1315 /* set valid and queue the idle timers only if it hasn't been 1316 * shut down already */ 1317 if (nn->nn_sc == sc) { 1318 o2net_sc_reset_idle_timer(sc); 1319 atomic_set(&nn->nn_timeout, 0); 1320 o2net_set_nn_state(nn, sc, 1, 0); 1321 } 1322 spin_unlock(&nn->nn_lock); 1323 1324 /* shift everything up as though it wasn't there */ 1325 sc->sc_page_off -= sizeof(struct o2net_handshake); 1326 if (sc->sc_page_off) 1327 memmove(hand, hand + 1, sc->sc_page_off); 1328 1329 return 0; 1330} 1331 1332/* this demuxes the queued rx bytes into header or payload bits and calls 1333 * handlers as each full message is read off the socket. it returns -error, 1334 * == 0 eof, or > 0 for progress made.*/ 1335static int o2net_advance_rx(struct o2net_sock_container *sc) 1336{ 1337 struct o2net_msg *hdr; 1338 int ret = 0; 1339 void *data; 1340 size_t datalen; 1341 1342 sclog(sc, "receiving\n"); 1343 o2net_set_advance_start_time(sc); 1344 1345 if (unlikely(sc->sc_handshake_ok == 0)) { 1346 if(sc->sc_page_off < sizeof(struct o2net_handshake)) { 1347 data = page_address(sc->sc_page) + sc->sc_page_off; 1348 datalen = sizeof(struct o2net_handshake) - sc->sc_page_off; 1349 ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen); 1350 if (ret > 0) 1351 sc->sc_page_off += ret; 1352 } 1353 1354 if (sc->sc_page_off == sizeof(struct o2net_handshake)) { 1355 o2net_check_handshake(sc); 1356 if (unlikely(sc->sc_handshake_ok == 0)) 1357 ret = -EPROTO; 1358 } 1359 goto out; 1360 } 1361 1362 /* do we need more header? */ 1363 if (sc->sc_page_off < sizeof(struct o2net_msg)) { 1364 data = page_address(sc->sc_page) + sc->sc_page_off; 1365 datalen = sizeof(struct o2net_msg) - sc->sc_page_off; 1366 ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen); 1367 if (ret > 0) { 1368 sc->sc_page_off += ret; 1369 /* only swab incoming here.. we can 1370 * only get here once as we cross from 1371 * being under to over */ 1372 if (sc->sc_page_off == sizeof(struct o2net_msg)) { 1373 hdr = page_address(sc->sc_page); 1374 if (be16_to_cpu(hdr->data_len) > 1375 O2NET_MAX_PAYLOAD_BYTES) 1376 ret = -EOVERFLOW; 1377 } 1378 } 1379 if (ret <= 0) 1380 goto out; 1381 } 1382 1383 if (sc->sc_page_off < sizeof(struct o2net_msg)) { 1384 /* oof, still don't have a header */ 1385 goto out; 1386 } 1387 1388 /* this was swabbed above when we first read it */ 1389 hdr = page_address(sc->sc_page); 1390 1391 msglog(hdr, "at page_off %zu\n", sc->sc_page_off); 1392 1393 /* do we need more payload? */ 1394 if (sc->sc_page_off - sizeof(struct o2net_msg) < be16_to_cpu(hdr->data_len)) { 1395 /* need more payload */ 1396 data = page_address(sc->sc_page) + sc->sc_page_off; 1397 datalen = (sizeof(struct o2net_msg) + be16_to_cpu(hdr->data_len)) - 1398 sc->sc_page_off; 1399 ret = o2net_recv_tcp_msg(sc->sc_sock, data, datalen); 1400 if (ret > 0) 1401 sc->sc_page_off += ret; 1402 if (ret <= 0) 1403 goto out; 1404 } 1405 1406 if (sc->sc_page_off - sizeof(struct o2net_msg) == be16_to_cpu(hdr->data_len)) { 1407 /* we can only get here once, the first time we read 1408 * the payload.. so set ret to progress if the handler 1409 * works out. after calling this the message is toast */ 1410 ret = o2net_process_message(sc, hdr); 1411 if (ret == 0) 1412 ret = 1; 1413 sc->sc_page_off = 0; 1414 } 1415 1416out: 1417 sclog(sc, "ret = %d\n", ret); 1418 o2net_set_advance_stop_time(sc); 1419 return ret; 1420} 1421 1422/* this work func is triggerd by data ready. it reads until it can read no 1423 * more. it interprets 0, eof, as fatal. if data_ready hits while we're doing 1424 * our work the work struct will be marked and we'll be called again. */ 1425static void o2net_rx_until_empty(struct work_struct *work) 1426{ 1427 struct o2net_sock_container *sc = 1428 container_of(work, struct o2net_sock_container, sc_rx_work); 1429 int ret; 1430 1431 do { 1432 ret = o2net_advance_rx(sc); 1433 } while (ret > 0); 1434 1435 if (ret <= 0 && ret != -EAGAIN) { 1436 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); 1437 sclog(sc, "saw error %d, closing\n", ret); 1438 /* not permanent so read failed handshake can retry */ 1439 o2net_ensure_shutdown(nn, sc, 0); 1440 } 1441 1442 sc_put(sc); 1443} 1444 1445static void o2net_initialize_handshake(void) 1446{ 1447 o2net_hand->o2hb_heartbeat_timeout_ms = cpu_to_be32( 1448 O2HB_MAX_WRITE_TIMEOUT_MS); 1449 o2net_hand->o2net_idle_timeout_ms = cpu_to_be32(o2net_idle_timeout()); 1450 o2net_hand->o2net_keepalive_delay_ms = cpu_to_be32( 1451 o2net_keepalive_delay()); 1452 o2net_hand->o2net_reconnect_delay_ms = cpu_to_be32( 1453 o2net_reconnect_delay()); 1454} 1455 1456/* ------------------------------------------------------------ */ 1457 1458/* called when a connect completes and after a sock is accepted. the 1459 * rx path will see the response and mark the sc valid */ 1460static void o2net_sc_connect_completed(struct work_struct *work) 1461{ 1462 struct o2net_sock_container *sc = 1463 container_of(work, struct o2net_sock_container, 1464 sc_connect_work); 1465 1466 mlog(ML_MSG, "sc sending handshake with ver %llu id %llx\n", 1467 (unsigned long long)O2NET_PROTOCOL_VERSION, 1468 (unsigned long long)be64_to_cpu(o2net_hand->connector_id)); 1469 1470 o2net_initialize_handshake(); 1471 o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand)); 1472 sc_put(sc); 1473} 1474 1475/* this is called as a work_struct func. */ 1476static void o2net_sc_send_keep_req(struct work_struct *work) 1477{ 1478 struct o2net_sock_container *sc = 1479 container_of(work, struct o2net_sock_container, 1480 sc_keepalive_work.work); 1481 1482 o2net_sendpage(sc, o2net_keep_req, sizeof(*o2net_keep_req)); 1483 sc_put(sc); 1484} 1485 1486/* socket shutdown does a del_timer_sync against this as it tears down. 1487 * we can't start this timer until we've got to the point in sc buildup 1488 * where shutdown is going to be involved */ 1489static void o2net_idle_timer(struct timer_list *t) 1490{ 1491 struct o2net_sock_container *sc = from_timer(sc, t, sc_idle_timeout); 1492 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); 1493#ifdef CONFIG_DEBUG_FS 1494 unsigned long msecs = ktime_to_ms(ktime_get()) - 1495 ktime_to_ms(sc->sc_tv_timer); 1496#else 1497 unsigned long msecs = o2net_idle_timeout(); 1498#endif 1499 1500 printk(KERN_NOTICE "o2net: Connection to " SC_NODEF_FMT " has been " 1501 "idle for %lu.%lu secs.\n", 1502 SC_NODEF_ARGS(sc), msecs / 1000, msecs % 1000); 1503 1504 /* idle timerout happen, don't shutdown the connection, but 1505 * make fence decision. Maybe the connection can recover before 1506 * the decision is made. 1507 */ 1508 atomic_set(&nn->nn_timeout, 1); 1509 o2quo_conn_err(o2net_num_from_nn(nn)); 1510 queue_delayed_work(o2net_wq, &nn->nn_still_up, 1511 msecs_to_jiffies(O2NET_QUORUM_DELAY_MS)); 1512 1513 o2net_sc_reset_idle_timer(sc); 1514 1515} 1516 1517static void o2net_sc_reset_idle_timer(struct o2net_sock_container *sc) 1518{ 1519 o2net_sc_cancel_delayed_work(sc, &sc->sc_keepalive_work); 1520 o2net_sc_queue_delayed_work(sc, &sc->sc_keepalive_work, 1521 msecs_to_jiffies(o2net_keepalive_delay())); 1522 o2net_set_sock_timer(sc); 1523 mod_timer(&sc->sc_idle_timeout, 1524 jiffies + msecs_to_jiffies(o2net_idle_timeout())); 1525} 1526 1527static void o2net_sc_postpone_idle(struct o2net_sock_container *sc) 1528{ 1529 struct o2net_node *nn = o2net_nn_from_num(sc->sc_node->nd_num); 1530 1531 /* clear fence decision since the connection recover from timeout*/ 1532 if (atomic_read(&nn->nn_timeout)) { 1533 o2quo_conn_up(o2net_num_from_nn(nn)); 1534 cancel_delayed_work(&nn->nn_still_up); 1535 atomic_set(&nn->nn_timeout, 0); 1536 } 1537 1538 /* Only push out an existing timer */ 1539 if (timer_pending(&sc->sc_idle_timeout)) 1540 o2net_sc_reset_idle_timer(sc); 1541} 1542 1543/* this work func is kicked whenever a path sets the nn state which doesn't 1544 * have valid set. This includes seeing hb come up, losing a connection, 1545 * having a connect attempt fail, etc. This centralizes the logic which decides 1546 * if a connect attempt should be made or if we should give up and all future 1547 * transmit attempts should fail */ 1548static void o2net_start_connect(struct work_struct *work) 1549{ 1550 struct o2net_node *nn = 1551 container_of(work, struct o2net_node, nn_connect_work.work); 1552 struct o2net_sock_container *sc = NULL; 1553 struct o2nm_node *node = NULL, *mynode = NULL; 1554 struct socket *sock = NULL; 1555 struct sockaddr_in myaddr = {0, }, remoteaddr = {0, }; 1556 int ret = 0, stop; 1557 unsigned int timeout; 1558 unsigned int nofs_flag; 1559 1560 /* 1561 * sock_create allocates the sock with GFP_KERNEL. We must 1562 * prevent the filesystem from being reentered by memory reclaim. 1563 */ 1564 nofs_flag = memalloc_nofs_save(); 1565 /* if we're greater we initiate tx, otherwise we accept */ 1566 if (o2nm_this_node() <= o2net_num_from_nn(nn)) 1567 goto out; 1568 1569 /* watch for racing with tearing a node down */ 1570 node = o2nm_get_node_by_num(o2net_num_from_nn(nn)); 1571 if (node == NULL) 1572 goto out; 1573 1574 mynode = o2nm_get_node_by_num(o2nm_this_node()); 1575 if (mynode == NULL) 1576 goto out; 1577 1578 spin_lock(&nn->nn_lock); 1579 /* 1580 * see if we already have one pending or have given up. 1581 * For nn_timeout, it is set when we close the connection 1582 * because of the idle time out. So it means that we have 1583 * at least connected to that node successfully once, 1584 * now try to connect to it again. 1585 */ 1586 timeout = atomic_read(&nn->nn_timeout); 1587 stop = (nn->nn_sc || 1588 (nn->nn_persistent_error && 1589 (nn->nn_persistent_error != -ENOTCONN || timeout == 0))); 1590 spin_unlock(&nn->nn_lock); 1591 if (stop) 1592 goto out; 1593 1594 nn->nn_last_connect_attempt = jiffies; 1595 1596 sc = sc_alloc(node); 1597 if (sc == NULL) { 1598 mlog(0, "couldn't allocate sc\n"); 1599 ret = -ENOMEM; 1600 goto out; 1601 } 1602 1603 ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock); 1604 if (ret < 0) { 1605 mlog(0, "can't create socket: %d\n", ret); 1606 goto out; 1607 } 1608 sc->sc_sock = sock; /* freed by sc_kref_release */ 1609 1610 sock->sk->sk_allocation = GFP_ATOMIC; 1611 sock->sk->sk_use_task_frag = false; 1612 1613 myaddr.sin_family = AF_INET; 1614 myaddr.sin_addr.s_addr = mynode->nd_ipv4_address; 1615 myaddr.sin_port = htons(0); /* any port */ 1616 1617 ret = sock->ops->bind(sock, (struct sockaddr *)&myaddr, 1618 sizeof(myaddr)); 1619 if (ret) { 1620 mlog(ML_ERROR, "bind failed with %d at address %pI4\n", 1621 ret, &mynode->nd_ipv4_address); 1622 goto out; 1623 } 1624 1625 tcp_sock_set_nodelay(sc->sc_sock->sk); 1626 tcp_sock_set_user_timeout(sock->sk, O2NET_TCP_USER_TIMEOUT); 1627 1628 o2net_register_callbacks(sc->sc_sock->sk, sc); 1629 1630 spin_lock(&nn->nn_lock); 1631 /* handshake completion will set nn->nn_sc_valid */ 1632 o2net_set_nn_state(nn, sc, 0, 0); 1633 spin_unlock(&nn->nn_lock); 1634 1635 remoteaddr.sin_family = AF_INET; 1636 remoteaddr.sin_addr.s_addr = node->nd_ipv4_address; 1637 remoteaddr.sin_port = node->nd_ipv4_port; 1638 1639 ret = sc->sc_sock->ops->connect(sc->sc_sock, 1640 (struct sockaddr *)&remoteaddr, 1641 sizeof(remoteaddr), 1642 O_NONBLOCK); 1643 if (ret == -EINPROGRESS) 1644 ret = 0; 1645 1646out: 1647 if (ret && sc) { 1648 printk(KERN_NOTICE "o2net: Connect attempt to " SC_NODEF_FMT 1649 " failed with errno %d\n", SC_NODEF_ARGS(sc), ret); 1650 /* 0 err so that another will be queued and attempted 1651 * from set_nn_state */ 1652 o2net_ensure_shutdown(nn, sc, 0); 1653 } 1654 if (sc) 1655 sc_put(sc); 1656 if (node) 1657 o2nm_node_put(node); 1658 if (mynode) 1659 o2nm_node_put(mynode); 1660 1661 memalloc_nofs_restore(nofs_flag); 1662 return; 1663} 1664 1665static void o2net_connect_expired(struct work_struct *work) 1666{ 1667 struct o2net_node *nn = 1668 container_of(work, struct o2net_node, nn_connect_expired.work); 1669 1670 spin_lock(&nn->nn_lock); 1671 if (!nn->nn_sc_valid) { 1672 printk(KERN_NOTICE "o2net: No connection established with " 1673 "node %u after %u.%u seconds, check network and" 1674 " cluster configuration.\n", 1675 o2net_num_from_nn(nn), 1676 o2net_idle_timeout() / 1000, 1677 o2net_idle_timeout() % 1000); 1678 1679 o2net_set_nn_state(nn, NULL, 0, 0); 1680 } 1681 spin_unlock(&nn->nn_lock); 1682} 1683 1684static void o2net_still_up(struct work_struct *work) 1685{ 1686 struct o2net_node *nn = 1687 container_of(work, struct o2net_node, nn_still_up.work); 1688 1689 o2quo_hb_still_up(o2net_num_from_nn(nn)); 1690} 1691 1692/* ------------------------------------------------------------ */ 1693 1694void o2net_disconnect_node(struct o2nm_node *node) 1695{ 1696 struct o2net_node *nn = o2net_nn_from_num(node->nd_num); 1697 1698 /* don't reconnect until it's heartbeating again */ 1699 spin_lock(&nn->nn_lock); 1700 atomic_set(&nn->nn_timeout, 0); 1701 o2net_set_nn_state(nn, NULL, 0, -ENOTCONN); 1702 spin_unlock(&nn->nn_lock); 1703 1704 if (o2net_wq) { 1705 cancel_delayed_work(&nn->nn_connect_expired); 1706 cancel_delayed_work(&nn->nn_connect_work); 1707 cancel_delayed_work(&nn->nn_still_up); 1708 flush_workqueue(o2net_wq); 1709 } 1710} 1711 1712static void o2net_hb_node_down_cb(struct o2nm_node *node, int node_num, 1713 void *data) 1714{ 1715 o2quo_hb_down(node_num); 1716 1717 if (!node) 1718 return; 1719 1720 if (node_num != o2nm_this_node()) 1721 o2net_disconnect_node(node); 1722 1723 BUG_ON(atomic_read(&o2net_connected_peers) < 0); 1724} 1725 1726static void o2net_hb_node_up_cb(struct o2nm_node *node, int node_num, 1727 void *data) 1728{ 1729 struct o2net_node *nn = o2net_nn_from_num(node_num); 1730 1731 o2quo_hb_up(node_num); 1732 1733 BUG_ON(!node); 1734 1735 /* ensure an immediate connect attempt */ 1736 nn->nn_last_connect_attempt = jiffies - 1737 (msecs_to_jiffies(o2net_reconnect_delay()) + 1); 1738 1739 if (node_num != o2nm_this_node()) { 1740 /* believe it or not, accept and node heartbeating testing 1741 * can succeed for this node before we got here.. so 1742 * only use set_nn_state to clear the persistent error 1743 * if that hasn't already happened */ 1744 spin_lock(&nn->nn_lock); 1745 atomic_set(&nn->nn_timeout, 0); 1746 if (nn->nn_persistent_error) 1747 o2net_set_nn_state(nn, NULL, 0, 0); 1748 spin_unlock(&nn->nn_lock); 1749 } 1750} 1751 1752void o2net_unregister_hb_callbacks(void) 1753{ 1754 o2hb_unregister_callback(NULL, &o2net_hb_up); 1755 o2hb_unregister_callback(NULL, &o2net_hb_down); 1756} 1757 1758int o2net_register_hb_callbacks(void) 1759{ 1760 int ret; 1761 1762 o2hb_setup_callback(&o2net_hb_down, O2HB_NODE_DOWN_CB, 1763 o2net_hb_node_down_cb, NULL, O2NET_HB_PRI); 1764 o2hb_setup_callback(&o2net_hb_up, O2HB_NODE_UP_CB, 1765 o2net_hb_node_up_cb, NULL, O2NET_HB_PRI); 1766 1767 ret = o2hb_register_callback(NULL, &o2net_hb_up); 1768 if (ret == 0) 1769 ret = o2hb_register_callback(NULL, &o2net_hb_down); 1770 1771 if (ret) 1772 o2net_unregister_hb_callbacks(); 1773 1774 return ret; 1775} 1776 1777/* ------------------------------------------------------------ */ 1778 1779static int o2net_accept_one(struct socket *sock, int *more) 1780{ 1781 int ret; 1782 struct sockaddr_in sin; 1783 struct socket *new_sock = NULL; 1784 struct o2nm_node *node = NULL; 1785 struct o2nm_node *local_node = NULL; 1786 struct o2net_sock_container *sc = NULL; 1787 struct o2net_node *nn; 1788 unsigned int nofs_flag; 1789 1790 /* 1791 * sock_create_lite allocates the sock with GFP_KERNEL. We must 1792 * prevent the filesystem from being reentered by memory reclaim. 1793 */ 1794 nofs_flag = memalloc_nofs_save(); 1795 1796 BUG_ON(sock == NULL); 1797 *more = 0; 1798 ret = sock_create_lite(sock->sk->sk_family, sock->sk->sk_type, 1799 sock->sk->sk_protocol, &new_sock); 1800 if (ret) 1801 goto out; 1802 1803 new_sock->type = sock->type; 1804 new_sock->ops = sock->ops; 1805 ret = sock->ops->accept(sock, new_sock, O_NONBLOCK, false); 1806 if (ret < 0) 1807 goto out; 1808 1809 *more = 1; 1810 new_sock->sk->sk_allocation = GFP_ATOMIC; 1811 1812 tcp_sock_set_nodelay(new_sock->sk); 1813 tcp_sock_set_user_timeout(new_sock->sk, O2NET_TCP_USER_TIMEOUT); 1814 1815 ret = new_sock->ops->getname(new_sock, (struct sockaddr *) &sin, 1); 1816 if (ret < 0) 1817 goto out; 1818 1819 node = o2nm_get_node_by_ip(sin.sin_addr.s_addr); 1820 if (node == NULL) { 1821 printk(KERN_NOTICE "o2net: Attempt to connect from unknown " 1822 "node at %pI4:%d\n", &sin.sin_addr.s_addr, 1823 ntohs(sin.sin_port)); 1824 ret = -EINVAL; 1825 goto out; 1826 } 1827 1828 if (o2nm_this_node() >= node->nd_num) { 1829 local_node = o2nm_get_node_by_num(o2nm_this_node()); 1830 if (local_node) 1831 printk(KERN_NOTICE "o2net: Unexpected connect attempt " 1832 "seen at node '%s' (%u, %pI4:%d) from " 1833 "node '%s' (%u, %pI4:%d)\n", 1834 local_node->nd_name, local_node->nd_num, 1835 &(local_node->nd_ipv4_address), 1836 ntohs(local_node->nd_ipv4_port), 1837 node->nd_name, 1838 node->nd_num, &sin.sin_addr.s_addr, 1839 ntohs(sin.sin_port)); 1840 ret = -EINVAL; 1841 goto out; 1842 } 1843 1844 /* this happens all the time when the other node sees our heartbeat 1845 * and tries to connect before we see their heartbeat */ 1846 if (!o2hb_check_node_heartbeating_from_callback(node->nd_num)) { 1847 mlog(ML_CONN, "attempt to connect from node '%s' at " 1848 "%pI4:%d but it isn't heartbeating\n", 1849 node->nd_name, &sin.sin_addr.s_addr, 1850 ntohs(sin.sin_port)); 1851 ret = -EINVAL; 1852 goto out; 1853 } 1854 1855 nn = o2net_nn_from_num(node->nd_num); 1856 1857 spin_lock(&nn->nn_lock); 1858 if (nn->nn_sc) 1859 ret = -EBUSY; 1860 else 1861 ret = 0; 1862 spin_unlock(&nn->nn_lock); 1863 if (ret) { 1864 printk(KERN_NOTICE "o2net: Attempt to connect from node '%s' " 1865 "at %pI4:%d but it already has an open connection\n", 1866 node->nd_name, &sin.sin_addr.s_addr, 1867 ntohs(sin.sin_port)); 1868 goto out; 1869 } 1870 1871 sc = sc_alloc(node); 1872 if (sc == NULL) { 1873 ret = -ENOMEM; 1874 goto out; 1875 } 1876 1877 sc->sc_sock = new_sock; 1878 new_sock = NULL; 1879 1880 spin_lock(&nn->nn_lock); 1881 atomic_set(&nn->nn_timeout, 0); 1882 o2net_set_nn_state(nn, sc, 0, 0); 1883 spin_unlock(&nn->nn_lock); 1884 1885 o2net_register_callbacks(sc->sc_sock->sk, sc); 1886 o2net_sc_queue_work(sc, &sc->sc_rx_work); 1887 1888 o2net_initialize_handshake(); 1889 o2net_sendpage(sc, o2net_hand, sizeof(*o2net_hand)); 1890 1891out: 1892 if (new_sock) 1893 sock_release(new_sock); 1894 if (node) 1895 o2nm_node_put(node); 1896 if (local_node) 1897 o2nm_node_put(local_node); 1898 if (sc) 1899 sc_put(sc); 1900 1901 memalloc_nofs_restore(nofs_flag); 1902 return ret; 1903} 1904 1905/* 1906 * This function is invoked in response to one or more 1907 * pending accepts at softIRQ level. We must drain the 1908 * entire que before returning. 1909 */ 1910 1911static void o2net_accept_many(struct work_struct *work) 1912{ 1913 struct socket *sock = o2net_listen_sock; 1914 int more; 1915 1916 /* 1917 * It is critical to note that due to interrupt moderation 1918 * at the network driver level, we can't assume to get a 1919 * softIRQ for every single conn since tcp SYN packets 1920 * can arrive back-to-back, and therefore many pending 1921 * accepts may result in just 1 softIRQ. If we terminate 1922 * the o2net_accept_one() loop upon seeing an err, what happens 1923 * to the rest of the conns in the queue? If no new SYN 1924 * arrives for hours, no softIRQ will be delivered, 1925 * and the connections will just sit in the queue. 1926 */ 1927 1928 for (;;) { 1929 o2net_accept_one(sock, &more); 1930 if (!more) 1931 break; 1932 cond_resched(); 1933 } 1934} 1935 1936static void o2net_listen_data_ready(struct sock *sk) 1937{ 1938 void (*ready)(struct sock *sk); 1939 1940 trace_sk_data_ready(sk); 1941 1942 read_lock_bh(&sk->sk_callback_lock); 1943 ready = sk->sk_user_data; 1944 if (ready == NULL) { /* check for teardown race */ 1945 ready = sk->sk_data_ready; 1946 goto out; 1947 } 1948 1949 /* This callback may called twice when a new connection 1950 * is being established as a child socket inherits everything 1951 * from a parent LISTEN socket, including the data_ready cb of 1952 * the parent. This leads to a hazard. In o2net_accept_one() 1953 * we are still initializing the child socket but have not 1954 * changed the inherited data_ready callback yet when 1955 * data starts arriving. 1956 * We avoid this hazard by checking the state. 1957 * For the listening socket, the state will be TCP_LISTEN; for the new 1958 * socket, will be TCP_ESTABLISHED. Also, in this case, 1959 * sk->sk_user_data is not a valid function pointer. 1960 */ 1961 1962 if (sk->sk_state == TCP_LISTEN) { 1963 queue_work(o2net_wq, &o2net_listen_work); 1964 } else { 1965 ready = NULL; 1966 } 1967 1968out: 1969 read_unlock_bh(&sk->sk_callback_lock); 1970 if (ready != NULL) 1971 ready(sk); 1972} 1973 1974static int o2net_open_listening_sock(__be32 addr, __be16 port) 1975{ 1976 struct socket *sock = NULL; 1977 int ret; 1978 struct sockaddr_in sin = { 1979 .sin_family = PF_INET, 1980 .sin_addr = { .s_addr = addr }, 1981 .sin_port = port, 1982 }; 1983 1984 ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock); 1985 if (ret < 0) { 1986 printk(KERN_ERR "o2net: Error %d while creating socket\n", ret); 1987 goto out; 1988 } 1989 1990 sock->sk->sk_allocation = GFP_ATOMIC; 1991 1992 write_lock_bh(&sock->sk->sk_callback_lock); 1993 sock->sk->sk_user_data = sock->sk->sk_data_ready; 1994 sock->sk->sk_data_ready = o2net_listen_data_ready; 1995 write_unlock_bh(&sock->sk->sk_callback_lock); 1996 1997 o2net_listen_sock = sock; 1998 INIT_WORK(&o2net_listen_work, o2net_accept_many); 1999 2000 sock->sk->sk_reuse = SK_CAN_REUSE; 2001 ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin)); 2002 if (ret < 0) { 2003 printk(KERN_ERR "o2net: Error %d while binding socket at " 2004 "%pI4:%u\n", ret, &addr, ntohs(port)); 2005 goto out; 2006 } 2007 2008 ret = sock->ops->listen(sock, 64); 2009 if (ret < 0) 2010 printk(KERN_ERR "o2net: Error %d while listening on %pI4:%u\n", 2011 ret, &addr, ntohs(port)); 2012 2013out: 2014 if (ret) { 2015 o2net_listen_sock = NULL; 2016 if (sock) 2017 sock_release(sock); 2018 } 2019 return ret; 2020} 2021 2022/* 2023 * called from node manager when we should bring up our network listening 2024 * socket. node manager handles all the serialization to only call this 2025 * once and to match it with o2net_stop_listening(). note, 2026 * o2nm_this_node() doesn't work yet as we're being called while it 2027 * is being set up. 2028 */ 2029int o2net_start_listening(struct o2nm_node *node) 2030{ 2031 int ret = 0; 2032 2033 BUG_ON(o2net_wq != NULL); 2034 BUG_ON(o2net_listen_sock != NULL); 2035 2036 mlog(ML_KTHREAD, "starting o2net thread...\n"); 2037 o2net_wq = alloc_ordered_workqueue("o2net", WQ_MEM_RECLAIM); 2038 if (o2net_wq == NULL) { 2039 mlog(ML_ERROR, "unable to launch o2net thread\n"); 2040 return -ENOMEM; /* ? */ 2041 } 2042 2043 ret = o2net_open_listening_sock(node->nd_ipv4_address, 2044 node->nd_ipv4_port); 2045 if (ret) { 2046 destroy_workqueue(o2net_wq); 2047 o2net_wq = NULL; 2048 } else 2049 o2quo_conn_up(node->nd_num); 2050 2051 return ret; 2052} 2053 2054/* again, o2nm_this_node() doesn't work here as we're involved in 2055 * tearing it down */ 2056void o2net_stop_listening(struct o2nm_node *node) 2057{ 2058 struct socket *sock = o2net_listen_sock; 2059 size_t i; 2060 2061 BUG_ON(o2net_wq == NULL); 2062 BUG_ON(o2net_listen_sock == NULL); 2063 2064 /* stop the listening socket from generating work */ 2065 write_lock_bh(&sock->sk->sk_callback_lock); 2066 sock->sk->sk_data_ready = sock->sk->sk_user_data; 2067 sock->sk->sk_user_data = NULL; 2068 write_unlock_bh(&sock->sk->sk_callback_lock); 2069 2070 for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) { 2071 struct o2nm_node *node = o2nm_get_node_by_num(i); 2072 if (node) { 2073 o2net_disconnect_node(node); 2074 o2nm_node_put(node); 2075 } 2076 } 2077 2078 /* finish all work and tear down the work queue */ 2079 mlog(ML_KTHREAD, "waiting for o2net thread to exit....\n"); 2080 destroy_workqueue(o2net_wq); 2081 o2net_wq = NULL; 2082 2083 sock_release(o2net_listen_sock); 2084 o2net_listen_sock = NULL; 2085 2086 o2quo_conn_err(node->nd_num); 2087} 2088 2089/* ------------------------------------------------------------ */ 2090 2091int o2net_init(void) 2092{ 2093 struct folio *folio; 2094 void *p; 2095 unsigned long i; 2096 2097 o2quo_init(); 2098 o2net_debugfs_init(); 2099 2100 folio = folio_alloc(GFP_KERNEL | __GFP_ZERO, 0); 2101 if (!folio) 2102 goto out; 2103 2104 p = folio_address(folio); 2105 o2net_hand = p; 2106 p += sizeof(struct o2net_handshake); 2107 o2net_keep_req = p; 2108 p += sizeof(struct o2net_msg); 2109 o2net_keep_resp = p; 2110 2111 o2net_hand->protocol_version = cpu_to_be64(O2NET_PROTOCOL_VERSION); 2112 o2net_hand->connector_id = cpu_to_be64(1); 2113 2114 o2net_keep_req->magic = cpu_to_be16(O2NET_MSG_KEEP_REQ_MAGIC); 2115 o2net_keep_resp->magic = cpu_to_be16(O2NET_MSG_KEEP_RESP_MAGIC); 2116 2117 for (i = 0; i < ARRAY_SIZE(o2net_nodes); i++) { 2118 struct o2net_node *nn = o2net_nn_from_num(i); 2119 2120 atomic_set(&nn->nn_timeout, 0); 2121 spin_lock_init(&nn->nn_lock); 2122 INIT_DELAYED_WORK(&nn->nn_connect_work, o2net_start_connect); 2123 INIT_DELAYED_WORK(&nn->nn_connect_expired, 2124 o2net_connect_expired); 2125 INIT_DELAYED_WORK(&nn->nn_still_up, o2net_still_up); 2126 /* until we see hb from a node we'll return einval */ 2127 nn->nn_persistent_error = -ENOTCONN; 2128 init_waitqueue_head(&nn->nn_sc_wq); 2129 idr_init(&nn->nn_status_idr); 2130 INIT_LIST_HEAD(&nn->nn_status_list); 2131 } 2132 2133 return 0; 2134 2135out: 2136 o2net_debugfs_exit(); 2137 o2quo_exit(); 2138 return -ENOMEM; 2139} 2140 2141void o2net_exit(void) 2142{ 2143 o2quo_exit(); 2144 o2net_debugfs_exit(); 2145 folio_put(virt_to_folio(o2net_hand)); 2146} 2147