1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Common framework for low-level network console, dump, and debugger code 4 * 5 * Sep 8 2003 Matt Mackall <mpm@selenic.com> 6 * 7 * based on the netconsole code from: 8 * 9 * Copyright (C) 2001 Ingo Molnar <mingo@redhat.com> 10 * Copyright (C) 2002 Red Hat, Inc. 11 */ 12 13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 14 15 #include <linux/moduleparam.h> 16 #include <linux/kernel.h> 17 #include <linux/netdevice.h> 18 #include <linux/etherdevice.h> 19 #include <linux/string.h> 20 #include <linux/if_arp.h> 21 #include <linux/inetdevice.h> 22 #include <linux/inet.h> 23 #include <linux/interrupt.h> 24 #include <linux/netpoll.h> 25 #include <linux/sched.h> 26 #include <linux/delay.h> 27 #include <linux/rcupdate.h> 28 #include <linux/workqueue.h> 29 #include <linux/slab.h> 30 #include <linux/export.h> 31 #include <linux/if_vlan.h> 32 #include <net/tcp.h> 33 #include <net/udp.h> 34 #include <net/addrconf.h> 35 #include <net/ndisc.h> 36 #include <net/ip6_checksum.h> 37 #include <asm/unaligned.h> 38 #include <trace/events/napi.h> 39 #include <linux/kconfig.h> 40 41 /* 42 * We maintain a small pool of fully-sized skbs, to make sure the 43 * message gets out even in extreme OOM situations. 44 */ 45 46 #define MAX_UDP_CHUNK 1460 47 #define MAX_SKBS 32 48 49 static struct sk_buff_head skb_pool; 50 51 DEFINE_STATIC_SRCU(netpoll_srcu); 52 53 #define USEC_PER_POLL 50 54 55 #define MAX_SKB_SIZE \ 56 (sizeof(struct ethhdr) + \ 57 sizeof(struct iphdr) + \ 58 sizeof(struct udphdr) + \ 59 MAX_UDP_CHUNK) 60 61 static void zap_completion_queue(void); 62 63 static unsigned int carrier_timeout = 4; 64 module_param(carrier_timeout, uint, 0644); 65 66 #define np_info(np, fmt, ...) \ 67 pr_info("%s: " fmt, np->name, ##__VA_ARGS__) 68 #define np_err(np, fmt, ...) \ 69 pr_err("%s: " fmt, np->name, ##__VA_ARGS__) 70 #define np_notice(np, fmt, ...) \ 71 pr_notice("%s: " fmt, np->name, ##__VA_ARGS__) 72 73 static netdev_tx_t netpoll_start_xmit(struct sk_buff *skb, 74 struct net_device *dev, 75 struct netdev_queue *txq) 76 { 77 netdev_tx_t status = NETDEV_TX_OK; 78 netdev_features_t features; 79 80 features = netif_skb_features(skb); 81 82 if (skb_vlan_tag_present(skb) && 83 !vlan_hw_offload_capable(features, skb->vlan_proto)) { 84 skb = __vlan_hwaccel_push_inside(skb); 85 if (unlikely(!skb)) { 86 /* This is actually a packet drop, but we 87 * don't want the code that calls this 88 * function to try and operate on a NULL skb. 89 */ 90 goto out; 91 } 92 } 93 94 status = netdev_start_xmit(skb, dev, txq, false); 95 96 out: 97 return status; 98 } 99 100 static void queue_process(struct work_struct *work) 101 { 102 struct netpoll_info *npinfo = 103 container_of(work, struct netpoll_info, tx_work.work); 104 struct sk_buff *skb; 105 unsigned long flags; 106 107 while ((skb = skb_dequeue(&npinfo->txq))) { 108 struct net_device *dev = skb->dev; 109 struct netdev_queue *txq; 110 unsigned int q_index; 111 112 if (!netif_device_present(dev) || !netif_running(dev)) { 113 kfree_skb(skb); 114 continue; 115 } 116 117 local_irq_save(flags); 118 /* check if skb->queue_mapping is still valid */ 119 q_index = skb_get_queue_mapping(skb); 120 if (unlikely(q_index >= dev->real_num_tx_queues)) { 121 q_index = q_index % dev->real_num_tx_queues; 122 skb_set_queue_mapping(skb, q_index); 123 } 124 txq = netdev_get_tx_queue(dev, q_index); 125 HARD_TX_LOCK(dev, txq, smp_processor_id()); 126 if (netif_xmit_frozen_or_stopped(txq) || 127 !dev_xmit_complete(netpoll_start_xmit(skb, dev, txq))) { 128 skb_queue_head(&npinfo->txq, skb); 129 HARD_TX_UNLOCK(dev, txq); 130 local_irq_restore(flags); 131 132 schedule_delayed_work(&npinfo->tx_work, HZ/10); 133 return; 134 } 135 HARD_TX_UNLOCK(dev, txq); 136 local_irq_restore(flags); 137 } 138 } 139 140 static int netif_local_xmit_active(struct net_device *dev) 141 { 142 int i; 143 144 for (i = 0; i < dev->num_tx_queues; i++) { 145 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 146 147 if (READ_ONCE(txq->xmit_lock_owner) == smp_processor_id()) 148 return 1; 149 } 150 151 return 0; 152 } 153 154 static void poll_one_napi(struct napi_struct *napi) 155 { 156 int work; 157 158 /* If we set this bit but see that it has already been set, 159 * that indicates that napi has been disabled and we need 160 * to abort this operation 161 */ 162 if (test_and_set_bit(NAPI_STATE_NPSVC, &napi->state)) 163 return; 164 165 /* We explicilty pass the polling call a budget of 0 to 166 * indicate that we are clearing the Tx path only. 167 */ 168 work = napi->poll(napi, 0); 169 WARN_ONCE(work, "%pS exceeded budget in poll\n", napi->poll); 170 trace_napi_poll(napi, work, 0); 171 172 clear_bit(NAPI_STATE_NPSVC, &napi->state); 173 } 174 175 static void poll_napi(struct net_device *dev) 176 { 177 struct napi_struct *napi; 178 int cpu = smp_processor_id(); 179 180 list_for_each_entry_rcu(napi, &dev->napi_list, dev_list) { 181 if (cmpxchg(&napi->poll_owner, -1, cpu) == -1) { 182 poll_one_napi(napi); 183 smp_store_release(&napi->poll_owner, -1); 184 } 185 } 186 } 187 188 void netpoll_poll_dev(struct net_device *dev) 189 { 190 struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo); 191 const struct net_device_ops *ops; 192 193 /* Don't do any rx activity if the dev_lock mutex is held 194 * the dev_open/close paths use this to block netpoll activity 195 * while changing device state 196 */ 197 if (!ni || down_trylock(&ni->dev_lock)) 198 return; 199 200 /* Some drivers will take the same locks in poll and xmit, 201 * we can't poll if local CPU is already in xmit. 202 */ 203 if (!netif_running(dev) || netif_local_xmit_active(dev)) { 204 up(&ni->dev_lock); 205 return; 206 } 207 208 ops = dev->netdev_ops; 209 if (ops->ndo_poll_controller) 210 ops->ndo_poll_controller(dev); 211 212 poll_napi(dev); 213 214 up(&ni->dev_lock); 215 216 zap_completion_queue(); 217 } 218 EXPORT_SYMBOL(netpoll_poll_dev); 219 220 void netpoll_poll_disable(struct net_device *dev) 221 { 222 struct netpoll_info *ni; 223 int idx; 224 might_sleep(); 225 idx = srcu_read_lock(&netpoll_srcu); 226 ni = srcu_dereference(dev->npinfo, &netpoll_srcu); 227 if (ni) 228 down(&ni->dev_lock); 229 srcu_read_unlock(&netpoll_srcu, idx); 230 } 231 232 void netpoll_poll_enable(struct net_device *dev) 233 { 234 struct netpoll_info *ni; 235 rcu_read_lock(); 236 ni = rcu_dereference(dev->npinfo); 237 if (ni) 238 up(&ni->dev_lock); 239 rcu_read_unlock(); 240 } 241 242 static void refill_skbs(void) 243 { 244 struct sk_buff *skb; 245 unsigned long flags; 246 247 spin_lock_irqsave(&skb_pool.lock, flags); 248 while (skb_pool.qlen < MAX_SKBS) { 249 skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC); 250 if (!skb) 251 break; 252 253 __skb_queue_tail(&skb_pool, skb); 254 } 255 spin_unlock_irqrestore(&skb_pool.lock, flags); 256 } 257 258 static void zap_completion_queue(void) 259 { 260 unsigned long flags; 261 struct softnet_data *sd = &get_cpu_var(softnet_data); 262 263 if (sd->completion_queue) { 264 struct sk_buff *clist; 265 266 local_irq_save(flags); 267 clist = sd->completion_queue; 268 sd->completion_queue = NULL; 269 local_irq_restore(flags); 270 271 while (clist != NULL) { 272 struct sk_buff *skb = clist; 273 clist = clist->next; 274 if (!skb_irq_freeable(skb)) { 275 refcount_set(&skb->users, 1); 276 dev_kfree_skb_any(skb); /* put this one back */ 277 } else { 278 __kfree_skb(skb); 279 } 280 } 281 } 282 283 put_cpu_var(softnet_data); 284 } 285 286 static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve) 287 { 288 int count = 0; 289 struct sk_buff *skb; 290 291 zap_completion_queue(); 292 refill_skbs(); 293 repeat: 294 295 skb = alloc_skb(len, GFP_ATOMIC); 296 if (!skb) 297 skb = skb_dequeue(&skb_pool); 298 299 if (!skb) { 300 if (++count < 10) { 301 netpoll_poll_dev(np->dev); 302 goto repeat; 303 } 304 return NULL; 305 } 306 307 refcount_set(&skb->users, 1); 308 skb_reserve(skb, reserve); 309 return skb; 310 } 311 312 static int netpoll_owner_active(struct net_device *dev) 313 { 314 struct napi_struct *napi; 315 316 list_for_each_entry_rcu(napi, &dev->napi_list, dev_list) { 317 if (READ_ONCE(napi->poll_owner) == smp_processor_id()) 318 return 1; 319 } 320 return 0; 321 } 322 323 /* call with IRQ disabled */ 324 static netdev_tx_t __netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) 325 { 326 netdev_tx_t status = NETDEV_TX_BUSY; 327 struct net_device *dev; 328 unsigned long tries; 329 /* It is up to the caller to keep npinfo alive. */ 330 struct netpoll_info *npinfo; 331 332 lockdep_assert_irqs_disabled(); 333 334 dev = np->dev; 335 npinfo = rcu_dereference_bh(dev->npinfo); 336 337 if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) { 338 dev_kfree_skb_irq(skb); 339 return NET_XMIT_DROP; 340 } 341 342 /* don't get messages out of order, and no recursion */ 343 if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) { 344 struct netdev_queue *txq; 345 346 txq = netdev_core_pick_tx(dev, skb, NULL); 347 348 /* try until next clock tick */ 349 for (tries = jiffies_to_usecs(1)/USEC_PER_POLL; 350 tries > 0; --tries) { 351 if (HARD_TX_TRYLOCK(dev, txq)) { 352 if (!netif_xmit_stopped(txq)) 353 status = netpoll_start_xmit(skb, dev, txq); 354 355 HARD_TX_UNLOCK(dev, txq); 356 357 if (dev_xmit_complete(status)) 358 break; 359 360 } 361 362 /* tickle device maybe there is some cleanup */ 363 netpoll_poll_dev(np->dev); 364 365 udelay(USEC_PER_POLL); 366 } 367 368 WARN_ONCE(!irqs_disabled(), 369 "netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pS)\n", 370 dev->name, dev->netdev_ops->ndo_start_xmit); 371 372 } 373 374 if (!dev_xmit_complete(status)) { 375 skb_queue_tail(&npinfo->txq, skb); 376 schedule_delayed_work(&npinfo->tx_work,0); 377 } 378 return NETDEV_TX_OK; 379 } 380 381 netdev_tx_t netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) 382 { 383 unsigned long flags; 384 netdev_tx_t ret; 385 386 if (unlikely(!np)) { 387 dev_kfree_skb_irq(skb); 388 ret = NET_XMIT_DROP; 389 } else { 390 local_irq_save(flags); 391 ret = __netpoll_send_skb(np, skb); 392 local_irq_restore(flags); 393 } 394 return ret; 395 } 396 EXPORT_SYMBOL(netpoll_send_skb); 397 398 void netpoll_send_udp(struct netpoll *np, const char *msg, int len) 399 { 400 int total_len, ip_len, udp_len; 401 struct sk_buff *skb; 402 struct udphdr *udph; 403 struct iphdr *iph; 404 struct ethhdr *eth; 405 static atomic_t ip_ident; 406 struct ipv6hdr *ip6h; 407 408 if (!IS_ENABLED(CONFIG_PREEMPT_RT)) 409 WARN_ON_ONCE(!irqs_disabled()); 410 411 udp_len = len + sizeof(*udph); 412 if (np->ipv6) 413 ip_len = udp_len + sizeof(*ip6h); 414 else 415 ip_len = udp_len + sizeof(*iph); 416 417 total_len = ip_len + LL_RESERVED_SPACE(np->dev); 418 419 skb = find_skb(np, total_len + np->dev->needed_tailroom, 420 total_len - len); 421 if (!skb) 422 return; 423 424 skb_copy_to_linear_data(skb, msg, len); 425 skb_put(skb, len); 426 427 skb_push(skb, sizeof(*udph)); 428 skb_reset_transport_header(skb); 429 udph = udp_hdr(skb); 430 udph->source = htons(np->local_port); 431 udph->dest = htons(np->remote_port); 432 udph->len = htons(udp_len); 433 434 if (np->ipv6) { 435 udph->check = 0; 436 udph->check = csum_ipv6_magic(&np->local_ip.in6, 437 &np->remote_ip.in6, 438 udp_len, IPPROTO_UDP, 439 csum_partial(udph, udp_len, 0)); 440 if (udph->check == 0) 441 udph->check = CSUM_MANGLED_0; 442 443 skb_push(skb, sizeof(*ip6h)); 444 skb_reset_network_header(skb); 445 ip6h = ipv6_hdr(skb); 446 447 /* ip6h->version = 6; ip6h->priority = 0; */ 448 *(unsigned char *)ip6h = 0x60; 449 ip6h->flow_lbl[0] = 0; 450 ip6h->flow_lbl[1] = 0; 451 ip6h->flow_lbl[2] = 0; 452 453 ip6h->payload_len = htons(sizeof(struct udphdr) + len); 454 ip6h->nexthdr = IPPROTO_UDP; 455 ip6h->hop_limit = 32; 456 ip6h->saddr = np->local_ip.in6; 457 ip6h->daddr = np->remote_ip.in6; 458 459 eth = skb_push(skb, ETH_HLEN); 460 skb_reset_mac_header(skb); 461 skb->protocol = eth->h_proto = htons(ETH_P_IPV6); 462 } else { 463 udph->check = 0; 464 udph->check = csum_tcpudp_magic(np->local_ip.ip, 465 np->remote_ip.ip, 466 udp_len, IPPROTO_UDP, 467 csum_partial(udph, udp_len, 0)); 468 if (udph->check == 0) 469 udph->check = CSUM_MANGLED_0; 470 471 skb_push(skb, sizeof(*iph)); 472 skb_reset_network_header(skb); 473 iph = ip_hdr(skb); 474 475 /* iph->version = 4; iph->ihl = 5; */ 476 *(unsigned char *)iph = 0x45; 477 iph->tos = 0; 478 put_unaligned(htons(ip_len), &(iph->tot_len)); 479 iph->id = htons(atomic_inc_return(&ip_ident)); 480 iph->frag_off = 0; 481 iph->ttl = 64; 482 iph->protocol = IPPROTO_UDP; 483 iph->check = 0; 484 put_unaligned(np->local_ip.ip, &(iph->saddr)); 485 put_unaligned(np->remote_ip.ip, &(iph->daddr)); 486 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); 487 488 eth = skb_push(skb, ETH_HLEN); 489 skb_reset_mac_header(skb); 490 skb->protocol = eth->h_proto = htons(ETH_P_IP); 491 } 492 493 ether_addr_copy(eth->h_source, np->dev->dev_addr); 494 ether_addr_copy(eth->h_dest, np->remote_mac); 495 496 skb->dev = np->dev; 497 498 netpoll_send_skb(np, skb); 499 } 500 EXPORT_SYMBOL(netpoll_send_udp); 501 502 void netpoll_print_options(struct netpoll *np) 503 { 504 np_info(np, "local port %d\n", np->local_port); 505 if (np->ipv6) 506 np_info(np, "local IPv6 address %pI6c\n", &np->local_ip.in6); 507 else 508 np_info(np, "local IPv4 address %pI4\n", &np->local_ip.ip); 509 np_info(np, "interface '%s'\n", np->dev_name); 510 np_info(np, "remote port %d\n", np->remote_port); 511 if (np->ipv6) 512 np_info(np, "remote IPv6 address %pI6c\n", &np->remote_ip.in6); 513 else 514 np_info(np, "remote IPv4 address %pI4\n", &np->remote_ip.ip); 515 np_info(np, "remote ethernet address %pM\n", np->remote_mac); 516 } 517 EXPORT_SYMBOL(netpoll_print_options); 518 519 static int netpoll_parse_ip_addr(const char *str, union inet_addr *addr) 520 { 521 const char *end; 522 523 if (!strchr(str, ':') && 524 in4_pton(str, -1, (void *)addr, -1, &end) > 0) { 525 if (!*end) 526 return 0; 527 } 528 if (in6_pton(str, -1, addr->in6.s6_addr, -1, &end) > 0) { 529 #if IS_ENABLED(CONFIG_IPV6) 530 if (!*end) 531 return 1; 532 #else 533 return -1; 534 #endif 535 } 536 return -1; 537 } 538 539 int netpoll_parse_options(struct netpoll *np, char *opt) 540 { 541 char *cur=opt, *delim; 542 int ipv6; 543 bool ipversion_set = false; 544 545 if (*cur != '@') { 546 if ((delim = strchr(cur, '@')) == NULL) 547 goto parse_failed; 548 *delim = 0; 549 if (kstrtou16(cur, 10, &np->local_port)) 550 goto parse_failed; 551 cur = delim; 552 } 553 cur++; 554 555 if (*cur != '/') { 556 ipversion_set = true; 557 if ((delim = strchr(cur, '/')) == NULL) 558 goto parse_failed; 559 *delim = 0; 560 ipv6 = netpoll_parse_ip_addr(cur, &np->local_ip); 561 if (ipv6 < 0) 562 goto parse_failed; 563 else 564 np->ipv6 = (bool)ipv6; 565 cur = delim; 566 } 567 cur++; 568 569 if (*cur != ',') { 570 /* parse out dev name */ 571 if ((delim = strchr(cur, ',')) == NULL) 572 goto parse_failed; 573 *delim = 0; 574 strscpy(np->dev_name, cur, sizeof(np->dev_name)); 575 cur = delim; 576 } 577 cur++; 578 579 if (*cur != '@') { 580 /* dst port */ 581 if ((delim = strchr(cur, '@')) == NULL) 582 goto parse_failed; 583 *delim = 0; 584 if (*cur == ' ' || *cur == '\t') 585 np_info(np, "warning: whitespace is not allowed\n"); 586 if (kstrtou16(cur, 10, &np->remote_port)) 587 goto parse_failed; 588 cur = delim; 589 } 590 cur++; 591 592 /* dst ip */ 593 if ((delim = strchr(cur, '/')) == NULL) 594 goto parse_failed; 595 *delim = 0; 596 ipv6 = netpoll_parse_ip_addr(cur, &np->remote_ip); 597 if (ipv6 < 0) 598 goto parse_failed; 599 else if (ipversion_set && np->ipv6 != (bool)ipv6) 600 goto parse_failed; 601 else 602 np->ipv6 = (bool)ipv6; 603 cur = delim + 1; 604 605 if (*cur != 0) { 606 /* MAC address */ 607 if (!mac_pton(cur, np->remote_mac)) 608 goto parse_failed; 609 } 610 611 netpoll_print_options(np); 612 613 return 0; 614 615 parse_failed: 616 np_info(np, "couldn't parse config at '%s'!\n", cur); 617 return -1; 618 } 619 EXPORT_SYMBOL(netpoll_parse_options); 620 621 int __netpoll_setup(struct netpoll *np, struct net_device *ndev) 622 { 623 struct netpoll_info *npinfo; 624 const struct net_device_ops *ops; 625 int err; 626 627 np->dev = ndev; 628 strscpy(np->dev_name, ndev->name, IFNAMSIZ); 629 630 if (ndev->priv_flags & IFF_DISABLE_NETPOLL) { 631 np_err(np, "%s doesn't support polling, aborting\n", 632 np->dev_name); 633 err = -ENOTSUPP; 634 goto out; 635 } 636 637 if (!ndev->npinfo) { 638 npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL); 639 if (!npinfo) { 640 err = -ENOMEM; 641 goto out; 642 } 643 644 sema_init(&npinfo->dev_lock, 1); 645 skb_queue_head_init(&npinfo->txq); 646 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process); 647 648 refcount_set(&npinfo->refcnt, 1); 649 650 ops = np->dev->netdev_ops; 651 if (ops->ndo_netpoll_setup) { 652 err = ops->ndo_netpoll_setup(ndev, npinfo); 653 if (err) 654 goto free_npinfo; 655 } 656 } else { 657 npinfo = rtnl_dereference(ndev->npinfo); 658 refcount_inc(&npinfo->refcnt); 659 } 660 661 npinfo->netpoll = np; 662 663 /* last thing to do is link it to the net device structure */ 664 rcu_assign_pointer(ndev->npinfo, npinfo); 665 666 return 0; 667 668 free_npinfo: 669 kfree(npinfo); 670 out: 671 return err; 672 } 673 EXPORT_SYMBOL_GPL(__netpoll_setup); 674 675 int netpoll_setup(struct netpoll *np) 676 { 677 struct net_device *ndev = NULL; 678 struct in_device *in_dev; 679 int err; 680 681 rtnl_lock(); 682 if (np->dev_name[0]) { 683 struct net *net = current->nsproxy->net_ns; 684 ndev = __dev_get_by_name(net, np->dev_name); 685 } 686 if (!ndev) { 687 np_err(np, "%s doesn't exist, aborting\n", np->dev_name); 688 err = -ENODEV; 689 goto unlock; 690 } 691 netdev_hold(ndev, &np->dev_tracker, GFP_KERNEL); 692 693 if (netdev_master_upper_dev_get(ndev)) { 694 np_err(np, "%s is a slave device, aborting\n", np->dev_name); 695 err = -EBUSY; 696 goto put; 697 } 698 699 if (!netif_running(ndev)) { 700 unsigned long atmost; 701 702 np_info(np, "device %s not up yet, forcing it\n", np->dev_name); 703 704 err = dev_open(ndev, NULL); 705 706 if (err) { 707 np_err(np, "failed to open %s\n", ndev->name); 708 goto put; 709 } 710 711 rtnl_unlock(); 712 atmost = jiffies + carrier_timeout * HZ; 713 while (!netif_carrier_ok(ndev)) { 714 if (time_after(jiffies, atmost)) { 715 np_notice(np, "timeout waiting for carrier\n"); 716 break; 717 } 718 msleep(1); 719 } 720 721 rtnl_lock(); 722 } 723 724 if (!np->local_ip.ip) { 725 if (!np->ipv6) { 726 const struct in_ifaddr *ifa; 727 728 in_dev = __in_dev_get_rtnl(ndev); 729 if (!in_dev) 730 goto put_noaddr; 731 732 ifa = rtnl_dereference(in_dev->ifa_list); 733 if (!ifa) { 734 put_noaddr: 735 np_err(np, "no IP address for %s, aborting\n", 736 np->dev_name); 737 err = -EDESTADDRREQ; 738 goto put; 739 } 740 741 np->local_ip.ip = ifa->ifa_local; 742 np_info(np, "local IP %pI4\n", &np->local_ip.ip); 743 } else { 744 #if IS_ENABLED(CONFIG_IPV6) 745 struct inet6_dev *idev; 746 747 err = -EDESTADDRREQ; 748 idev = __in6_dev_get(ndev); 749 if (idev) { 750 struct inet6_ifaddr *ifp; 751 752 read_lock_bh(&idev->lock); 753 list_for_each_entry(ifp, &idev->addr_list, if_list) { 754 if (!!(ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL) != 755 !!(ipv6_addr_type(&np->remote_ip.in6) & IPV6_ADDR_LINKLOCAL)) 756 continue; 757 np->local_ip.in6 = ifp->addr; 758 err = 0; 759 break; 760 } 761 read_unlock_bh(&idev->lock); 762 } 763 if (err) { 764 np_err(np, "no IPv6 address for %s, aborting\n", 765 np->dev_name); 766 goto put; 767 } else 768 np_info(np, "local IPv6 %pI6c\n", &np->local_ip.in6); 769 #else 770 np_err(np, "IPv6 is not supported %s, aborting\n", 771 np->dev_name); 772 err = -EINVAL; 773 goto put; 774 #endif 775 } 776 } 777 778 /* fill up the skb queue */ 779 refill_skbs(); 780 781 err = __netpoll_setup(np, ndev); 782 if (err) 783 goto put; 784 rtnl_unlock(); 785 return 0; 786 787 put: 788 netdev_put(ndev, &np->dev_tracker); 789 unlock: 790 rtnl_unlock(); 791 return err; 792 } 793 EXPORT_SYMBOL(netpoll_setup); 794 795 static int __init netpoll_init(void) 796 { 797 skb_queue_head_init(&skb_pool); 798 return 0; 799 } 800 core_initcall(netpoll_init); 801 802 static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head) 803 { 804 struct netpoll_info *npinfo = 805 container_of(rcu_head, struct netpoll_info, rcu); 806 807 skb_queue_purge(&npinfo->txq); 808 809 /* we can't call cancel_delayed_work_sync here, as we are in softirq */ 810 cancel_delayed_work(&npinfo->tx_work); 811 812 /* clean after last, unfinished work */ 813 __skb_queue_purge(&npinfo->txq); 814 /* now cancel it again */ 815 cancel_delayed_work(&npinfo->tx_work); 816 kfree(npinfo); 817 } 818 819 void __netpoll_cleanup(struct netpoll *np) 820 { 821 struct netpoll_info *npinfo; 822 823 npinfo = rtnl_dereference(np->dev->npinfo); 824 if (!npinfo) 825 return; 826 827 synchronize_srcu(&netpoll_srcu); 828 829 if (refcount_dec_and_test(&npinfo->refcnt)) { 830 const struct net_device_ops *ops; 831 832 ops = np->dev->netdev_ops; 833 if (ops->ndo_netpoll_cleanup) 834 ops->ndo_netpoll_cleanup(np->dev); 835 836 RCU_INIT_POINTER(np->dev->npinfo, NULL); 837 call_rcu(&npinfo->rcu, rcu_cleanup_netpoll_info); 838 } else 839 RCU_INIT_POINTER(np->dev->npinfo, NULL); 840 } 841 EXPORT_SYMBOL_GPL(__netpoll_cleanup); 842 843 void __netpoll_free(struct netpoll *np) 844 { 845 ASSERT_RTNL(); 846 847 /* Wait for transmitting packets to finish before freeing. */ 848 synchronize_rcu(); 849 __netpoll_cleanup(np); 850 kfree(np); 851 } 852 EXPORT_SYMBOL_GPL(__netpoll_free); 853 854 void netpoll_cleanup(struct netpoll *np) 855 { 856 rtnl_lock(); 857 if (!np->dev) 858 goto out; 859 __netpoll_cleanup(np); 860 netdev_put(np->dev, &np->dev_tracker); 861 np->dev = NULL; 862 out: 863 rtnl_unlock(); 864 } 865 EXPORT_SYMBOL(netpoll_cleanup); 866