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12#include <linux/moduleparam.h>
13#include <linux/netdevice.h>
14#include <linux/etherdevice.h>
15#include <linux/string.h>
16#include <linux/if_arp.h>
17#include <linux/inetdevice.h>
18#include <linux/inet.h>
19#include <linux/interrupt.h>
20#include <linux/netpoll.h>
21#include <linux/sched.h>
22#include <linux/delay.h>
23#include <linux/rcupdate.h>
24#include <linux/workqueue.h>
25#include <linux/slab.h>
26#include <net/tcp.h>
27#include <net/udp.h>
28#include <asm/unaligned.h>
29#include <trace/events/napi.h>
30
31
32
33
34
35
36#define MAX_UDP_CHUNK 1460
37#define MAX_SKBS 32
38
39static struct sk_buff_head skb_pool;
40
41static atomic_t trapped;
42
43#define USEC_PER_POLL 50
44#define NETPOLL_RX_ENABLED 1
45#define NETPOLL_RX_DROP 2
46
47#define MAX_SKB_SIZE \
48 (MAX_UDP_CHUNK + sizeof(struct udphdr) + \
49 sizeof(struct iphdr) + sizeof(struct ethhdr))
50
51static void zap_completion_queue(void);
52static void arp_reply(struct sk_buff *skb);
53
54static unsigned int carrier_timeout = 4;
55module_param(carrier_timeout, uint, 0644);
56
57static void queue_process(struct work_struct *work)
58{
59 struct netpoll_info *npinfo =
60 container_of(work, struct netpoll_info, tx_work.work);
61 struct sk_buff *skb;
62 unsigned long flags;
63
64 while ((skb = skb_dequeue(&npinfo->txq))) {
65 struct net_device *dev = skb->dev;
66 const struct net_device_ops *ops = dev->netdev_ops;
67 struct netdev_queue *txq;
68
69 if (!netif_device_present(dev) || !netif_running(dev)) {
70 __kfree_skb(skb);
71 continue;
72 }
73
74 txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
75
76 local_irq_save(flags);
77 __netif_tx_lock(txq, smp_processor_id());
78 if (netif_tx_queue_frozen_or_stopped(txq) ||
79 ops->ndo_start_xmit(skb, dev) != NETDEV_TX_OK) {
80 skb_queue_head(&npinfo->txq, skb);
81 __netif_tx_unlock(txq);
82 local_irq_restore(flags);
83
84 schedule_delayed_work(&npinfo->tx_work, HZ/10);
85 return;
86 }
87 __netif_tx_unlock(txq);
88 local_irq_restore(flags);
89 }
90}
91
92static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,
93 unsigned short ulen, __be32 saddr, __be32 daddr)
94{
95 __wsum psum;
96
97 if (uh->check == 0 || skb_csum_unnecessary(skb))
98 return 0;
99
100 psum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0);
101
102 if (skb->ip_summed == CHECKSUM_COMPLETE &&
103 !csum_fold(csum_add(psum, skb->csum)))
104 return 0;
105
106 skb->csum = psum;
107
108 return __skb_checksum_complete(skb);
109}
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127static int poll_one_napi(struct netpoll_info *npinfo,
128 struct napi_struct *napi, int budget)
129{
130 int work;
131
132
133
134
135
136 if (!test_bit(NAPI_STATE_SCHED, &napi->state))
137 return budget;
138
139 npinfo->rx_flags |= NETPOLL_RX_DROP;
140 atomic_inc(&trapped);
141 set_bit(NAPI_STATE_NPSVC, &napi->state);
142
143 work = napi->poll(napi, budget);
144 trace_napi_poll(napi);
145
146 clear_bit(NAPI_STATE_NPSVC, &napi->state);
147 atomic_dec(&trapped);
148 npinfo->rx_flags &= ~NETPOLL_RX_DROP;
149
150 return budget - work;
151}
152
153static void poll_napi(struct net_device *dev)
154{
155 struct napi_struct *napi;
156 int budget = 16;
157
158 list_for_each_entry(napi, &dev->napi_list, dev_list) {
159 if (napi->poll_owner != smp_processor_id() &&
160 spin_trylock(&napi->poll_lock)) {
161 budget = poll_one_napi(dev->npinfo, napi, budget);
162 spin_unlock(&napi->poll_lock);
163
164 if (!budget)
165 break;
166 }
167 }
168}
169
170static void service_arp_queue(struct netpoll_info *npi)
171{
172 if (npi) {
173 struct sk_buff *skb;
174
175 while ((skb = skb_dequeue(&npi->arp_tx)))
176 arp_reply(skb);
177 }
178}
179
180void netpoll_poll_dev(struct net_device *dev)
181{
182 const struct net_device_ops *ops;
183
184 if (!dev || !netif_running(dev))
185 return;
186
187 ops = dev->netdev_ops;
188 if (!ops->ndo_poll_controller)
189 return;
190
191
192 ops->ndo_poll_controller(dev);
193
194 poll_napi(dev);
195
196 service_arp_queue(dev->npinfo);
197
198 zap_completion_queue();
199}
200EXPORT_SYMBOL(netpoll_poll_dev);
201
202void netpoll_poll(struct netpoll *np)
203{
204 netpoll_poll_dev(np->dev);
205}
206EXPORT_SYMBOL(netpoll_poll);
207
208static void refill_skbs(void)
209{
210 struct sk_buff *skb;
211 unsigned long flags;
212
213 spin_lock_irqsave(&skb_pool.lock, flags);
214 while (skb_pool.qlen < MAX_SKBS) {
215 skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC);
216 if (!skb)
217 break;
218
219 __skb_queue_tail(&skb_pool, skb);
220 }
221 spin_unlock_irqrestore(&skb_pool.lock, flags);
222}
223
224static void zap_completion_queue(void)
225{
226 unsigned long flags;
227 struct softnet_data *sd = &get_cpu_var(softnet_data);
228
229 if (sd->completion_queue) {
230 struct sk_buff *clist;
231
232 local_irq_save(flags);
233 clist = sd->completion_queue;
234 sd->completion_queue = NULL;
235 local_irq_restore(flags);
236
237 while (clist != NULL) {
238 struct sk_buff *skb = clist;
239 clist = clist->next;
240 if (skb->destructor) {
241 atomic_inc(&skb->users);
242 dev_kfree_skb_any(skb);
243 } else {
244 __kfree_skb(skb);
245 }
246 }
247 }
248
249 put_cpu_var(softnet_data);
250}
251
252static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
253{
254 int count = 0;
255 struct sk_buff *skb;
256
257 zap_completion_queue();
258 refill_skbs();
259repeat:
260
261 skb = alloc_skb(len, GFP_ATOMIC);
262 if (!skb)
263 skb = skb_dequeue(&skb_pool);
264
265 if (!skb) {
266 if (++count < 10) {
267 netpoll_poll(np);
268 goto repeat;
269 }
270 return NULL;
271 }
272
273 atomic_set(&skb->users, 1);
274 skb_reserve(skb, reserve);
275 return skb;
276}
277
278static int netpoll_owner_active(struct net_device *dev)
279{
280 struct napi_struct *napi;
281
282 list_for_each_entry(napi, &dev->napi_list, dev_list) {
283 if (napi->poll_owner == smp_processor_id())
284 return 1;
285 }
286 return 0;
287}
288
289void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
290 struct net_device *dev)
291{
292 int status = NETDEV_TX_BUSY;
293 unsigned long tries;
294 const struct net_device_ops *ops = dev->netdev_ops;
295
296 struct netpoll_info *npinfo = np->dev->npinfo;
297
298 if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
299 __kfree_skb(skb);
300 return;
301 }
302
303
304 if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) {
305 struct netdev_queue *txq;
306 unsigned long flags;
307
308 txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
309
310 local_irq_save(flags);
311
312 for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
313 tries > 0; --tries) {
314 if (__netif_tx_trylock(txq)) {
315 if (!netif_tx_queue_stopped(txq)) {
316 dev->priv_flags |= IFF_IN_NETPOLL;
317 status = ops->ndo_start_xmit(skb, dev);
318 dev->priv_flags &= ~IFF_IN_NETPOLL;
319 if (status == NETDEV_TX_OK)
320 txq_trans_update(txq);
321 }
322 __netif_tx_unlock(txq);
323
324 if (status == NETDEV_TX_OK)
325 break;
326
327 }
328
329
330 netpoll_poll(np);
331
332 udelay(USEC_PER_POLL);
333 }
334
335 WARN_ONCE(!irqs_disabled(),
336 "netpoll_send_skb(): %s enabled interrupts in poll (%pF)\n",
337 dev->name, ops->ndo_start_xmit);
338
339 local_irq_restore(flags);
340 }
341
342 if (status != NETDEV_TX_OK) {
343 skb_queue_tail(&npinfo->txq, skb);
344 schedule_delayed_work(&npinfo->tx_work,0);
345 }
346}
347EXPORT_SYMBOL(netpoll_send_skb_on_dev);
348
349void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
350{
351 int total_len, eth_len, ip_len, udp_len;
352 struct sk_buff *skb;
353 struct udphdr *udph;
354 struct iphdr *iph;
355 struct ethhdr *eth;
356
357 udp_len = len + sizeof(*udph);
358 ip_len = eth_len = udp_len + sizeof(*iph);
359 total_len = eth_len + ETH_HLEN + NET_IP_ALIGN;
360
361 skb = find_skb(np, total_len, total_len - len);
362 if (!skb)
363 return;
364
365 skb_copy_to_linear_data(skb, msg, len);
366 skb->len += len;
367
368 skb_push(skb, sizeof(*udph));
369 skb_reset_transport_header(skb);
370 udph = udp_hdr(skb);
371 udph->source = htons(np->local_port);
372 udph->dest = htons(np->remote_port);
373 udph->len = htons(udp_len);
374 udph->check = 0;
375 udph->check = csum_tcpudp_magic(np->local_ip,
376 np->remote_ip,
377 udp_len, IPPROTO_UDP,
378 csum_partial(udph, udp_len, 0));
379 if (udph->check == 0)
380 udph->check = CSUM_MANGLED_0;
381
382 skb_push(skb, sizeof(*iph));
383 skb_reset_network_header(skb);
384 iph = ip_hdr(skb);
385
386
387 put_unaligned(0x45, (unsigned char *)iph);
388 iph->tos = 0;
389 put_unaligned(htons(ip_len), &(iph->tot_len));
390 iph->id = 0;
391 iph->frag_off = 0;
392 iph->ttl = 64;
393 iph->protocol = IPPROTO_UDP;
394 iph->check = 0;
395 put_unaligned(np->local_ip, &(iph->saddr));
396 put_unaligned(np->remote_ip, &(iph->daddr));
397 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
398
399 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
400 skb_reset_mac_header(skb);
401 skb->protocol = eth->h_proto = htons(ETH_P_IP);
402 memcpy(eth->h_source, np->dev->dev_addr, ETH_ALEN);
403 memcpy(eth->h_dest, np->remote_mac, ETH_ALEN);
404
405 skb->dev = np->dev;
406
407 netpoll_send_skb(np, skb);
408}
409EXPORT_SYMBOL(netpoll_send_udp);
410
411static void arp_reply(struct sk_buff *skb)
412{
413 struct netpoll_info *npinfo = skb->dev->npinfo;
414 struct arphdr *arp;
415 unsigned char *arp_ptr;
416 int size, type = ARPOP_REPLY, ptype = ETH_P_ARP;
417 __be32 sip, tip;
418 unsigned char *sha;
419 struct sk_buff *send_skb;
420 struct netpoll *np, *tmp;
421 unsigned long flags;
422 int hits = 0;
423
424 if (list_empty(&npinfo->rx_np))
425 return;
426
427
428
429 spin_lock_irqsave(&npinfo->rx_lock, flags);
430 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
431 if (np->dev == skb->dev)
432 hits++;
433 }
434 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
435
436
437 if (!hits)
438 return;
439
440
441 if (skb->dev->flags & IFF_NOARP)
442 return;
443
444 if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
445 return;
446
447 skb_reset_network_header(skb);
448 skb_reset_transport_header(skb);
449 arp = arp_hdr(skb);
450
451 if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
452 arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
453 arp->ar_pro != htons(ETH_P_IP) ||
454 arp->ar_op != htons(ARPOP_REQUEST))
455 return;
456
457 arp_ptr = (unsigned char *)(arp+1);
458
459 sha = arp_ptr;
460 arp_ptr += skb->dev->addr_len;
461 memcpy(&sip, arp_ptr, 4);
462 arp_ptr += 4;
463
464
465 arp_ptr += skb->dev->addr_len;
466 memcpy(&tip, arp_ptr, 4);
467
468
469 if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip))
470 return;
471
472 size = arp_hdr_len(skb->dev);
473
474 spin_lock_irqsave(&npinfo->rx_lock, flags);
475 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
476 if (tip != np->local_ip)
477 continue;
478
479 send_skb = find_skb(np, size + LL_ALLOCATED_SPACE(np->dev),
480 LL_RESERVED_SPACE(np->dev));
481 if (!send_skb)
482 continue;
483
484 skb_reset_network_header(send_skb);
485 arp = (struct arphdr *) skb_put(send_skb, size);
486 send_skb->dev = skb->dev;
487 send_skb->protocol = htons(ETH_P_ARP);
488
489
490 if (dev_hard_header(send_skb, skb->dev, ptype,
491 sha, np->dev->dev_addr,
492 send_skb->len) < 0) {
493 kfree_skb(send_skb);
494 continue;
495 }
496
497
498
499
500
501
502
503
504
505 arp->ar_hrd = htons(np->dev->type);
506 arp->ar_pro = htons(ETH_P_IP);
507 arp->ar_hln = np->dev->addr_len;
508 arp->ar_pln = 4;
509 arp->ar_op = htons(type);
510
511 arp_ptr = (unsigned char *)(arp + 1);
512 memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
513 arp_ptr += np->dev->addr_len;
514 memcpy(arp_ptr, &tip, 4);
515 arp_ptr += 4;
516 memcpy(arp_ptr, sha, np->dev->addr_len);
517 arp_ptr += np->dev->addr_len;
518 memcpy(arp_ptr, &sip, 4);
519
520 netpoll_send_skb(np, send_skb);
521
522
523
524 break;
525 }
526 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
527}
528
529int __netpoll_rx(struct sk_buff *skb)
530{
531 int proto, len, ulen;
532 int hits = 0;
533 struct iphdr *iph;
534 struct udphdr *uh;
535 struct netpoll_info *npinfo = skb->dev->npinfo;
536 struct netpoll *np, *tmp;
537
538 if (list_empty(&npinfo->rx_np))
539 goto out;
540
541 if (skb->dev->type != ARPHRD_ETHER)
542 goto out;
543
544
545 if (skb->protocol == htons(ETH_P_ARP) &&
546 atomic_read(&trapped)) {
547 skb_queue_tail(&npinfo->arp_tx, skb);
548 return 1;
549 }
550
551 proto = ntohs(eth_hdr(skb)->h_proto);
552 if (proto != ETH_P_IP)
553 goto out;
554 if (skb->pkt_type == PACKET_OTHERHOST)
555 goto out;
556 if (skb_shared(skb))
557 goto out;
558
559 iph = (struct iphdr *)skb->data;
560 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
561 goto out;
562 if (iph->ihl < 5 || iph->version != 4)
563 goto out;
564 if (!pskb_may_pull(skb, iph->ihl*4))
565 goto out;
566 if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
567 goto out;
568
569 len = ntohs(iph->tot_len);
570 if (skb->len < len || len < iph->ihl*4)
571 goto out;
572
573
574
575
576
577 if (pskb_trim_rcsum(skb, len))
578 goto out;
579
580 if (iph->protocol != IPPROTO_UDP)
581 goto out;
582
583 len -= iph->ihl*4;
584 uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);
585 ulen = ntohs(uh->len);
586
587 if (ulen != len)
588 goto out;
589 if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr))
590 goto out;
591
592 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
593 if (np->local_ip && np->local_ip != iph->daddr)
594 continue;
595 if (np->remote_ip && np->remote_ip != iph->saddr)
596 continue;
597 if (np->local_port && np->local_port != ntohs(uh->dest))
598 continue;
599
600 np->rx_hook(np, ntohs(uh->source),
601 (char *)(uh+1),
602 ulen - sizeof(struct udphdr));
603 hits++;
604 }
605
606 if (!hits)
607 goto out;
608
609 kfree_skb(skb);
610 return 1;
611
612out:
613 if (atomic_read(&trapped)) {
614 kfree_skb(skb);
615 return 1;
616 }
617
618 return 0;
619}
620
621void netpoll_print_options(struct netpoll *np)
622{
623 printk(KERN_INFO "%s: local port %d\n",
624 np->name, np->local_port);
625 printk(KERN_INFO "%s: local IP %pI4\n",
626 np->name, &np->local_ip);
627 printk(KERN_INFO "%s: interface '%s'\n",
628 np->name, np->dev_name);
629 printk(KERN_INFO "%s: remote port %d\n",
630 np->name, np->remote_port);
631 printk(KERN_INFO "%s: remote IP %pI4\n",
632 np->name, &np->remote_ip);
633 printk(KERN_INFO "%s: remote ethernet address %pM\n",
634 np->name, np->remote_mac);
635}
636EXPORT_SYMBOL(netpoll_print_options);
637
638int netpoll_parse_options(struct netpoll *np, char *opt)
639{
640 char *cur=opt, *delim;
641
642 if (*cur != '@') {
643 if ((delim = strchr(cur, '@')) == NULL)
644 goto parse_failed;
645 *delim = 0;
646 np->local_port = simple_strtol(cur, NULL, 10);
647 cur = delim;
648 }
649 cur++;
650
651 if (*cur != '/') {
652 if ((delim = strchr(cur, '/')) == NULL)
653 goto parse_failed;
654 *delim = 0;
655 np->local_ip = in_aton(cur);
656 cur = delim;
657 }
658 cur++;
659
660 if (*cur != ',') {
661
662 if ((delim = strchr(cur, ',')) == NULL)
663 goto parse_failed;
664 *delim = 0;
665 strlcpy(np->dev_name, cur, sizeof(np->dev_name));
666 cur = delim;
667 }
668 cur++;
669
670 if (*cur != '@') {
671
672 if ((delim = strchr(cur, '@')) == NULL)
673 goto parse_failed;
674 *delim = 0;
675 if (*cur == ' ' || *cur == '\t')
676 printk(KERN_INFO "%s: warning: whitespace"
677 "is not allowed\n", np->name);
678 np->remote_port = simple_strtol(cur, NULL, 10);
679 cur = delim;
680 }
681 cur++;
682
683
684 if ((delim = strchr(cur, '/')) == NULL)
685 goto parse_failed;
686 *delim = 0;
687 np->remote_ip = in_aton(cur);
688 cur = delim + 1;
689
690 if (*cur != 0) {
691
692 if ((delim = strchr(cur, ':')) == NULL)
693 goto parse_failed;
694 *delim = 0;
695 np->remote_mac[0] = simple_strtol(cur, NULL, 16);
696 cur = delim + 1;
697 if ((delim = strchr(cur, ':')) == NULL)
698 goto parse_failed;
699 *delim = 0;
700 np->remote_mac[1] = simple_strtol(cur, NULL, 16);
701 cur = delim + 1;
702 if ((delim = strchr(cur, ':')) == NULL)
703 goto parse_failed;
704 *delim = 0;
705 np->remote_mac[2] = simple_strtol(cur, NULL, 16);
706 cur = delim + 1;
707 if ((delim = strchr(cur, ':')) == NULL)
708 goto parse_failed;
709 *delim = 0;
710 np->remote_mac[3] = simple_strtol(cur, NULL, 16);
711 cur = delim + 1;
712 if ((delim = strchr(cur, ':')) == NULL)
713 goto parse_failed;
714 *delim = 0;
715 np->remote_mac[4] = simple_strtol(cur, NULL, 16);
716 cur = delim + 1;
717 np->remote_mac[5] = simple_strtol(cur, NULL, 16);
718 }
719
720 netpoll_print_options(np);
721
722 return 0;
723
724 parse_failed:
725 printk(KERN_INFO "%s: couldn't parse config at '%s'!\n",
726 np->name, cur);
727 return -1;
728}
729EXPORT_SYMBOL(netpoll_parse_options);
730
731int __netpoll_setup(struct netpoll *np)
732{
733 struct net_device *ndev = np->dev;
734 struct netpoll_info *npinfo;
735 const struct net_device_ops *ops;
736 unsigned long flags;
737 int err;
738
739 if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
740 !ndev->netdev_ops->ndo_poll_controller) {
741 printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
742 np->name, np->dev_name);
743 err = -ENOTSUPP;
744 goto out;
745 }
746
747 if (!ndev->npinfo) {
748 npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
749 if (!npinfo) {
750 err = -ENOMEM;
751 goto out;
752 }
753
754 npinfo->rx_flags = 0;
755 INIT_LIST_HEAD(&npinfo->rx_np);
756
757 spin_lock_init(&npinfo->rx_lock);
758 skb_queue_head_init(&npinfo->arp_tx);
759 skb_queue_head_init(&npinfo->txq);
760 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
761
762 atomic_set(&npinfo->refcnt, 1);
763
764 ops = np->dev->netdev_ops;
765 if (ops->ndo_netpoll_setup) {
766 err = ops->ndo_netpoll_setup(ndev, npinfo);
767 if (err)
768 goto free_npinfo;
769 }
770 } else {
771 npinfo = ndev->npinfo;
772 atomic_inc(&npinfo->refcnt);
773 }
774
775 npinfo->netpoll = np;
776
777 if (np->rx_hook) {
778 spin_lock_irqsave(&npinfo->rx_lock, flags);
779 npinfo->rx_flags |= NETPOLL_RX_ENABLED;
780 list_add_tail(&np->rx, &npinfo->rx_np);
781 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
782 }
783
784
785 rcu_assign_pointer(ndev->npinfo, npinfo);
786
787 return 0;
788
789free_npinfo:
790 kfree(npinfo);
791out:
792 return err;
793}
794EXPORT_SYMBOL_GPL(__netpoll_setup);
795
796int netpoll_setup(struct netpoll *np)
797{
798 struct net_device *ndev = NULL;
799 struct in_device *in_dev;
800 int err;
801
802 if (np->dev_name)
803 ndev = dev_get_by_name(&init_net, np->dev_name);
804 if (!ndev) {
805 printk(KERN_ERR "%s: %s doesn't exist, aborting.\n",
806 np->name, np->dev_name);
807 return -ENODEV;
808 }
809
810 if (!netif_running(ndev)) {
811 unsigned long atmost, atleast;
812
813 printk(KERN_INFO "%s: device %s not up yet, forcing it\n",
814 np->name, np->dev_name);
815
816 rtnl_lock();
817 err = dev_open(ndev);
818 rtnl_unlock();
819
820 if (err) {
821 printk(KERN_ERR "%s: failed to open %s\n",
822 np->name, ndev->name);
823 goto put;
824 }
825
826 atleast = jiffies + HZ/10;
827 atmost = jiffies + carrier_timeout * HZ;
828 while (!netif_carrier_ok(ndev)) {
829 if (time_after(jiffies, atmost)) {
830 printk(KERN_NOTICE
831 "%s: timeout waiting for carrier\n",
832 np->name);
833 break;
834 }
835 msleep(1);
836 }
837
838
839
840
841
842
843 if (time_before(jiffies, atleast)) {
844 printk(KERN_NOTICE "%s: carrier detect appears"
845 " untrustworthy, waiting 4 seconds\n",
846 np->name);
847 msleep(4000);
848 }
849 }
850
851 if (!np->local_ip) {
852 rcu_read_lock();
853 in_dev = __in_dev_get_rcu(ndev);
854
855 if (!in_dev || !in_dev->ifa_list) {
856 rcu_read_unlock();
857 printk(KERN_ERR "%s: no IP address for %s, aborting\n",
858 np->name, np->dev_name);
859 err = -EDESTADDRREQ;
860 goto put;
861 }
862
863 np->local_ip = in_dev->ifa_list->ifa_local;
864 rcu_read_unlock();
865 printk(KERN_INFO "%s: local IP %pI4\n", np->name, &np->local_ip);
866 }
867
868 np->dev = ndev;
869
870
871 refill_skbs();
872
873 rtnl_lock();
874 err = __netpoll_setup(np);
875 rtnl_unlock();
876
877 if (err)
878 goto put;
879
880 return 0;
881
882put:
883 dev_put(ndev);
884 return err;
885}
886EXPORT_SYMBOL(netpoll_setup);
887
888static int __init netpoll_init(void)
889{
890 skb_queue_head_init(&skb_pool);
891 return 0;
892}
893core_initcall(netpoll_init);
894
895void __netpoll_cleanup(struct netpoll *np)
896{
897 struct netpoll_info *npinfo;
898 unsigned long flags;
899
900 npinfo = np->dev->npinfo;
901 if (!npinfo)
902 return;
903
904 if (!list_empty(&npinfo->rx_np)) {
905 spin_lock_irqsave(&npinfo->rx_lock, flags);
906 list_del(&np->rx);
907 if (list_empty(&npinfo->rx_np))
908 npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
909 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
910 }
911
912 if (atomic_dec_and_test(&npinfo->refcnt)) {
913 const struct net_device_ops *ops;
914
915 ops = np->dev->netdev_ops;
916 if (ops->ndo_netpoll_cleanup)
917 ops->ndo_netpoll_cleanup(np->dev);
918
919 rcu_assign_pointer(np->dev->npinfo, NULL);
920
921
922 synchronize_rcu_bh();
923
924 skb_queue_purge(&npinfo->arp_tx);
925 skb_queue_purge(&npinfo->txq);
926 cancel_delayed_work_sync(&npinfo->tx_work);
927
928
929 __skb_queue_purge(&npinfo->txq);
930 kfree(npinfo);
931 }
932}
933EXPORT_SYMBOL_GPL(__netpoll_cleanup);
934
935void netpoll_cleanup(struct netpoll *np)
936{
937 if (!np->dev)
938 return;
939
940 rtnl_lock();
941 __netpoll_cleanup(np);
942 rtnl_unlock();
943
944 dev_put(np->dev);
945 np->dev = NULL;
946}
947EXPORT_SYMBOL(netpoll_cleanup);
948
949int netpoll_trap(void)
950{
951 return atomic_read(&trapped);
952}
953EXPORT_SYMBOL(netpoll_trap);
954
955void netpoll_set_trap(int trap)
956{
957 if (trap)
958 atomic_inc(&trapped);
959 else
960 atomic_dec(&trapped);
961}
962EXPORT_SYMBOL(netpoll_set_trap);
963