[SK_BUFF]: Introduce skb_reset_transport_header(skb)
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / core / netpoll.c
CommitLineData
1da177e4
LT
1/*
2 * Common framework for low-level network console, dump, and debugger code
3 *
4 * Sep 8 2003 Matt Mackall <mpm@selenic.com>
5 *
6 * based on the netconsole code from:
7 *
8 * Copyright (C) 2001 Ingo Molnar <mingo@redhat.com>
9 * Copyright (C) 2002 Red Hat, Inc.
10 */
11
12#include <linux/smp_lock.h>
13#include <linux/netdevice.h>
14#include <linux/etherdevice.h>
15#include <linux/string.h>
14c85021 16#include <linux/if_arp.h>
1da177e4
LT
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 <net/tcp.h>
26#include <net/udp.h>
27#include <asm/unaligned.h>
28
29/*
30 * We maintain a small pool of fully-sized skbs, to make sure the
31 * message gets out even in extreme OOM situations.
32 */
33
34#define MAX_UDP_CHUNK 1460
35#define MAX_SKBS 32
36#define MAX_QUEUE_DEPTH (MAX_SKBS / 2)
37
a1bcfacd 38static struct sk_buff_head skb_pool;
1da177e4
LT
39
40static atomic_t trapped;
41
2bdfe0ba 42#define USEC_PER_POLL 50
1da177e4
LT
43#define NETPOLL_RX_ENABLED 1
44#define NETPOLL_RX_DROP 2
45
46#define MAX_SKB_SIZE \
47 (MAX_UDP_CHUNK + sizeof(struct udphdr) + \
48 sizeof(struct iphdr) + sizeof(struct ethhdr))
49
50static void zap_completion_queue(void);
068c6e98 51static void arp_reply(struct sk_buff *skb);
1da177e4 52
c4028958 53static void queue_process(struct work_struct *work)
1da177e4 54{
4c1ac1b4
DH
55 struct netpoll_info *npinfo =
56 container_of(work, struct netpoll_info, tx_work.work);
1da177e4 57 struct sk_buff *skb;
3640543d 58 unsigned long flags;
1da177e4 59
6c43ff18
SH
60 while ((skb = skb_dequeue(&npinfo->txq))) {
61 struct net_device *dev = skb->dev;
1da177e4 62
6c43ff18
SH
63 if (!netif_device_present(dev) || !netif_running(dev)) {
64 __kfree_skb(skb);
65 continue;
66 }
1da177e4 67
3640543d
IM
68 local_irq_save(flags);
69 netif_tx_lock(dev);
6c43ff18
SH
70 if (netif_queue_stopped(dev) ||
71 dev->hard_start_xmit(skb, dev) != NETDEV_TX_OK) {
72 skb_queue_head(&npinfo->txq, skb);
3640543d
IM
73 netif_tx_unlock(dev);
74 local_irq_restore(flags);
1da177e4 75
6c43ff18
SH
76 schedule_delayed_work(&npinfo->tx_work, HZ/10);
77 return;
78 }
3640543d
IM
79 netif_tx_unlock(dev);
80 local_irq_restore(flags);
1da177e4 81 }
1da177e4
LT
82}
83
b51655b9
AV
84static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,
85 unsigned short ulen, __be32 saddr, __be32 daddr)
1da177e4 86{
d6f5493c 87 __wsum psum;
fb286bb2
HX
88
89 if (uh->check == 0 || skb->ip_summed == CHECKSUM_UNNECESSARY)
1da177e4
LT
90 return 0;
91
fb286bb2
HX
92 psum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0);
93
84fa7933 94 if (skb->ip_summed == CHECKSUM_COMPLETE &&
d3bc23e7 95 !csum_fold(csum_add(psum, skb->csum)))
fb286bb2 96 return 0;
1da177e4 97
fb286bb2 98 skb->csum = psum;
1da177e4 99
fb286bb2 100 return __skb_checksum_complete(skb);
1da177e4
LT
101}
102
103/*
104 * Check whether delayed processing was scheduled for our NIC. If so,
105 * we attempt to grab the poll lock and use ->poll() to pump the card.
106 * If this fails, either we've recursed in ->poll() or it's already
107 * running on another CPU.
108 *
109 * Note: we don't mask interrupts with this lock because we're using
110 * trylock here and interrupts are already disabled in the softirq
111 * case. Further, we test the poll_owner to avoid recursion on UP
112 * systems where the lock doesn't exist.
113 *
114 * In cases where there is bi-directional communications, reading only
115 * one message at a time can lead to packets being dropped by the
116 * network adapter, forcing superfluous retries and possibly timeouts.
117 * Thus, we set our budget to greater than 1.
118 */
119static void poll_napi(struct netpoll *np)
120{
115c1d6e 121 struct netpoll_info *npinfo = np->dev->npinfo;
1da177e4
LT
122 int budget = 16;
123
124 if (test_bit(__LINK_STATE_RX_SCHED, &np->dev->state) &&
115c1d6e
JM
125 npinfo->poll_owner != smp_processor_id() &&
126 spin_trylock(&npinfo->poll_lock)) {
127 npinfo->rx_flags |= NETPOLL_RX_DROP;
1da177e4
LT
128 atomic_inc(&trapped);
129
130 np->dev->poll(np->dev, &budget);
131
132 atomic_dec(&trapped);
115c1d6e
JM
133 npinfo->rx_flags &= ~NETPOLL_RX_DROP;
134 spin_unlock(&npinfo->poll_lock);
1da177e4
LT
135 }
136}
137
068c6e98
NH
138static void service_arp_queue(struct netpoll_info *npi)
139{
140 struct sk_buff *skb;
141
142 if (unlikely(!npi))
143 return;
144
145 skb = skb_dequeue(&npi->arp_tx);
146
147 while (skb != NULL) {
148 arp_reply(skb);
149 skb = skb_dequeue(&npi->arp_tx);
150 }
068c6e98
NH
151}
152
1da177e4
LT
153void netpoll_poll(struct netpoll *np)
154{
c68b9070 155 if (!np->dev || !netif_running(np->dev) || !np->dev->poll_controller)
1da177e4
LT
156 return;
157
158 /* Process pending work on NIC */
159 np->dev->poll_controller(np->dev);
160 if (np->dev->poll)
161 poll_napi(np);
162
068c6e98
NH
163 service_arp_queue(np->dev->npinfo);
164
1da177e4
LT
165 zap_completion_queue();
166}
167
168static void refill_skbs(void)
169{
170 struct sk_buff *skb;
171 unsigned long flags;
172
a1bcfacd
SH
173 spin_lock_irqsave(&skb_pool.lock, flags);
174 while (skb_pool.qlen < MAX_SKBS) {
1da177e4
LT
175 skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC);
176 if (!skb)
177 break;
178
a1bcfacd 179 __skb_queue_tail(&skb_pool, skb);
1da177e4 180 }
a1bcfacd 181 spin_unlock_irqrestore(&skb_pool.lock, flags);
1da177e4
LT
182}
183
184static void zap_completion_queue(void)
185{
186 unsigned long flags;
187 struct softnet_data *sd = &get_cpu_var(softnet_data);
188
189 if (sd->completion_queue) {
190 struct sk_buff *clist;
191
192 local_irq_save(flags);
193 clist = sd->completion_queue;
194 sd->completion_queue = NULL;
195 local_irq_restore(flags);
196
197 while (clist != NULL) {
198 struct sk_buff *skb = clist;
199 clist = clist->next;
c68b9070 200 if (skb->destructor)
1da177e4
LT
201 dev_kfree_skb_any(skb); /* put this one back */
202 else
203 __kfree_skb(skb);
204 }
205 }
206
207 put_cpu_var(softnet_data);
208}
209
a1bcfacd 210static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
1da177e4 211{
a1bcfacd
SH
212 int count = 0;
213 struct sk_buff *skb;
1da177e4
LT
214
215 zap_completion_queue();
a1bcfacd 216 refill_skbs();
1da177e4 217repeat:
1da177e4
LT
218
219 skb = alloc_skb(len, GFP_ATOMIC);
a1bcfacd
SH
220 if (!skb)
221 skb = skb_dequeue(&skb_pool);
1da177e4
LT
222
223 if (!skb) {
a1bcfacd
SH
224 if (++count < 10) {
225 netpoll_poll(np);
226 goto repeat;
1da177e4 227 }
a1bcfacd 228 return NULL;
1da177e4
LT
229 }
230
231 atomic_set(&skb->users, 1);
232 skb_reserve(skb, reserve);
233 return skb;
234}
235
236static void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
237{
2bdfe0ba
SH
238 int status = NETDEV_TX_BUSY;
239 unsigned long tries;
4ec93edb
YH
240 struct net_device *dev = np->dev;
241 struct netpoll_info *npinfo = np->dev->npinfo;
2bdfe0ba 242
4ec93edb
YH
243 if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
244 __kfree_skb(skb);
245 return;
246 }
2bdfe0ba
SH
247
248 /* don't get messages out of order, and no recursion */
c68b9070 249 if (skb_queue_len(&npinfo->txq) == 0 &&
e37b8d93 250 npinfo->poll_owner != smp_processor_id()) {
a49f99ff
AM
251 unsigned long flags;
252
253 local_irq_save(flags);
e37b8d93
AM
254 if (netif_tx_trylock(dev)) {
255 /* try until next clock tick */
256 for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
257 tries > 0; --tries) {
258 if (!netif_queue_stopped(dev))
259 status = dev->hard_start_xmit(skb, dev);
260
261 if (status == NETDEV_TX_OK)
262 break;
263
264 /* tickle device maybe there is some cleanup */
265 netpoll_poll(np);
266
267 udelay(USEC_PER_POLL);
268 }
269 netif_tx_unlock(dev);
0db1d6fc 270 }
a49f99ff 271 local_irq_restore(flags);
1da177e4 272 }
1da177e4 273
2bdfe0ba 274 if (status != NETDEV_TX_OK) {
5de4a473 275 skb_queue_tail(&npinfo->txq, skb);
4c1ac1b4 276 schedule_delayed_work(&npinfo->tx_work,0);
1da177e4 277 }
1da177e4
LT
278}
279
280void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
281{
282 int total_len, eth_len, ip_len, udp_len;
283 struct sk_buff *skb;
284 struct udphdr *udph;
285 struct iphdr *iph;
286 struct ethhdr *eth;
287
288 udp_len = len + sizeof(*udph);
289 ip_len = eth_len = udp_len + sizeof(*iph);
290 total_len = eth_len + ETH_HLEN + NET_IP_ALIGN;
291
292 skb = find_skb(np, total_len, total_len - len);
293 if (!skb)
294 return;
295
296 memcpy(skb->data, msg, len);
297 skb->len += len;
298
206daaf7 299 skb->h.uh = udph = (struct udphdr *) skb_push(skb, sizeof(*udph));
1da177e4
LT
300 udph->source = htons(np->local_port);
301 udph->dest = htons(np->remote_port);
302 udph->len = htons(udp_len);
303 udph->check = 0;
8e365eec
CL
304 udph->check = csum_tcpudp_magic(htonl(np->local_ip),
305 htonl(np->remote_ip),
306 udp_len, IPPROTO_UDP,
307 csum_partial((unsigned char *)udph, udp_len, 0));
308 if (udph->check == 0)
5e57dff2 309 udph->check = CSUM_MANGLED_0;
1da177e4 310
e2d1bca7
ACM
311 skb_push(skb, sizeof(*iph));
312 skb_reset_network_header(skb);
eddc9ec5 313 iph = ip_hdr(skb);
1da177e4
LT
314
315 /* iph->version = 4; iph->ihl = 5; */
316 put_unaligned(0x45, (unsigned char *)iph);
317 iph->tos = 0;
318 put_unaligned(htons(ip_len), &(iph->tot_len));
319 iph->id = 0;
320 iph->frag_off = 0;
321 iph->ttl = 64;
322 iph->protocol = IPPROTO_UDP;
323 iph->check = 0;
324 put_unaligned(htonl(np->local_ip), &(iph->saddr));
325 put_unaligned(htonl(np->remote_ip), &(iph->daddr));
326 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
327
328 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
459a98ed 329 skb_reset_mac_header(skb);
206daaf7 330 skb->protocol = eth->h_proto = htons(ETH_P_IP);
1da177e4
LT
331 memcpy(eth->h_source, np->local_mac, 6);
332 memcpy(eth->h_dest, np->remote_mac, 6);
333
334 skb->dev = np->dev;
335
336 netpoll_send_skb(np, skb);
337}
338
339static void arp_reply(struct sk_buff *skb)
340{
115c1d6e 341 struct netpoll_info *npinfo = skb->dev->npinfo;
1da177e4
LT
342 struct arphdr *arp;
343 unsigned char *arp_ptr;
344 int size, type = ARPOP_REPLY, ptype = ETH_P_ARP;
252e3346 345 __be32 sip, tip;
47bbec02 346 unsigned char *sha;
1da177e4 347 struct sk_buff *send_skb;
115c1d6e 348 struct netpoll *np = NULL;
1da177e4 349
fbeec2e1
JM
350 if (npinfo->rx_np && npinfo->rx_np->dev == skb->dev)
351 np = npinfo->rx_np;
115c1d6e
JM
352 if (!np)
353 return;
1da177e4
LT
354
355 /* No arp on this interface */
356 if (skb->dev->flags & IFF_NOARP)
357 return;
358
359 if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
360 (2 * skb->dev->addr_len) +
361 (2 * sizeof(u32)))))
362 return;
363
c1d2bbe1 364 skb_reset_network_header(skb);
badff6d0 365 skb_reset_transport_header(skb);
d0a92be0 366 arp = arp_hdr(skb);
1da177e4
LT
367
368 if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
369 arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
370 arp->ar_pro != htons(ETH_P_IP) ||
371 arp->ar_op != htons(ARPOP_REQUEST))
372 return;
373
47bbec02
NH
374 arp_ptr = (unsigned char *)(arp+1);
375 /* save the location of the src hw addr */
376 sha = arp_ptr;
377 arp_ptr += skb->dev->addr_len;
1da177e4 378 memcpy(&sip, arp_ptr, 4);
47bbec02
NH
379 arp_ptr += 4;
380 /* if we actually cared about dst hw addr, it would get copied here */
381 arp_ptr += skb->dev->addr_len;
1da177e4
LT
382 memcpy(&tip, arp_ptr, 4);
383
384 /* Should we ignore arp? */
385 if (tip != htonl(np->local_ip) || LOOPBACK(tip) || MULTICAST(tip))
386 return;
387
388 size = sizeof(struct arphdr) + 2 * (skb->dev->addr_len + 4);
389 send_skb = find_skb(np, size + LL_RESERVED_SPACE(np->dev),
390 LL_RESERVED_SPACE(np->dev));
391
392 if (!send_skb)
393 return;
394
c1d2bbe1 395 skb_reset_network_header(send_skb);
1da177e4
LT
396 arp = (struct arphdr *) skb_put(send_skb, size);
397 send_skb->dev = skb->dev;
398 send_skb->protocol = htons(ETH_P_ARP);
399
400 /* Fill the device header for the ARP frame */
401
402 if (np->dev->hard_header &&
403 np->dev->hard_header(send_skb, skb->dev, ptype,
47bbec02 404 sha, np->local_mac,
c68b9070 405 send_skb->len) < 0) {
1da177e4
LT
406 kfree_skb(send_skb);
407 return;
408 }
409
410 /*
411 * Fill out the arp protocol part.
412 *
413 * we only support ethernet device type,
414 * which (according to RFC 1390) should always equal 1 (Ethernet).
415 */
416
417 arp->ar_hrd = htons(np->dev->type);
418 arp->ar_pro = htons(ETH_P_IP);
419 arp->ar_hln = np->dev->addr_len;
420 arp->ar_pln = 4;
421 arp->ar_op = htons(type);
422
423 arp_ptr=(unsigned char *)(arp + 1);
424 memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
425 arp_ptr += np->dev->addr_len;
426 memcpy(arp_ptr, &tip, 4);
427 arp_ptr += 4;
47bbec02 428 memcpy(arp_ptr, sha, np->dev->addr_len);
1da177e4
LT
429 arp_ptr += np->dev->addr_len;
430 memcpy(arp_ptr, &sip, 4);
431
432 netpoll_send_skb(np, send_skb);
433}
434
435int __netpoll_rx(struct sk_buff *skb)
436{
437 int proto, len, ulen;
438 struct iphdr *iph;
439 struct udphdr *uh;
068c6e98
NH
440 struct netpoll_info *npi = skb->dev->npinfo;
441 struct netpoll *np = npi->rx_np;
442
fbeec2e1 443 if (!np)
1da177e4
LT
444 goto out;
445 if (skb->dev->type != ARPHRD_ETHER)
446 goto out;
447
448 /* check if netpoll clients need ARP */
724800d6 449 if (skb->protocol == htons(ETH_P_ARP) &&
1da177e4 450 atomic_read(&trapped)) {
068c6e98 451 skb_queue_tail(&npi->arp_tx, skb);
1da177e4
LT
452 return 1;
453 }
454
455 proto = ntohs(eth_hdr(skb)->h_proto);
456 if (proto != ETH_P_IP)
457 goto out;
458 if (skb->pkt_type == PACKET_OTHERHOST)
459 goto out;
460 if (skb_shared(skb))
461 goto out;
462
463 iph = (struct iphdr *)skb->data;
464 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
465 goto out;
466 if (iph->ihl < 5 || iph->version != 4)
467 goto out;
468 if (!pskb_may_pull(skb, iph->ihl*4))
469 goto out;
470 if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
471 goto out;
472
473 len = ntohs(iph->tot_len);
474 if (skb->len < len || len < iph->ihl*4)
475 goto out;
476
5e7d7fa5
AL
477 /*
478 * Our transport medium may have padded the buffer out.
479 * Now We trim to the true length of the frame.
480 */
481 if (pskb_trim_rcsum(skb, len))
482 goto out;
483
1da177e4
LT
484 if (iph->protocol != IPPROTO_UDP)
485 goto out;
486
487 len -= iph->ihl*4;
488 uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);
489 ulen = ntohs(uh->len);
490
491 if (ulen != len)
492 goto out;
fb286bb2 493 if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr))
1da177e4
LT
494 goto out;
495 if (np->local_ip && np->local_ip != ntohl(iph->daddr))
496 goto out;
497 if (np->remote_ip && np->remote_ip != ntohl(iph->saddr))
498 goto out;
499 if (np->local_port && np->local_port != ntohs(uh->dest))
500 goto out;
501
502 np->rx_hook(np, ntohs(uh->source),
503 (char *)(uh+1),
504 ulen - sizeof(struct udphdr));
505
506 kfree_skb(skb);
507 return 1;
508
509out:
510 if (atomic_read(&trapped)) {
511 kfree_skb(skb);
512 return 1;
513 }
514
515 return 0;
516}
517
518int netpoll_parse_options(struct netpoll *np, char *opt)
519{
520 char *cur=opt, *delim;
521
c68b9070 522 if (*cur != '@') {
1da177e4
LT
523 if ((delim = strchr(cur, '@')) == NULL)
524 goto parse_failed;
c68b9070
DM
525 *delim = 0;
526 np->local_port = simple_strtol(cur, NULL, 10);
527 cur = delim;
1da177e4
LT
528 }
529 cur++;
530 printk(KERN_INFO "%s: local port %d\n", np->name, np->local_port);
531
c68b9070 532 if (*cur != '/') {
1da177e4
LT
533 if ((delim = strchr(cur, '/')) == NULL)
534 goto parse_failed;
c68b9070
DM
535 *delim = 0;
536 np->local_ip = ntohl(in_aton(cur));
537 cur = delim;
1da177e4
LT
538
539 printk(KERN_INFO "%s: local IP %d.%d.%d.%d\n",
540 np->name, HIPQUAD(np->local_ip));
541 }
542 cur++;
543
c68b9070 544 if (*cur != ',') {
1da177e4
LT
545 /* parse out dev name */
546 if ((delim = strchr(cur, ',')) == NULL)
547 goto parse_failed;
c68b9070 548 *delim = 0;
1da177e4 549 strlcpy(np->dev_name, cur, sizeof(np->dev_name));
c68b9070 550 cur = delim;
1da177e4
LT
551 }
552 cur++;
553
554 printk(KERN_INFO "%s: interface %s\n", np->name, np->dev_name);
555
c68b9070 556 if (*cur != '@') {
1da177e4
LT
557 /* dst port */
558 if ((delim = strchr(cur, '@')) == NULL)
559 goto parse_failed;
c68b9070
DM
560 *delim = 0;
561 np->remote_port = simple_strtol(cur, NULL, 10);
562 cur = delim;
1da177e4
LT
563 }
564 cur++;
565 printk(KERN_INFO "%s: remote port %d\n", np->name, np->remote_port);
566
567 /* dst ip */
568 if ((delim = strchr(cur, '/')) == NULL)
569 goto parse_failed;
c68b9070
DM
570 *delim = 0;
571 np->remote_ip = ntohl(in_aton(cur));
572 cur = delim + 1;
1da177e4
LT
573
574 printk(KERN_INFO "%s: remote IP %d.%d.%d.%d\n",
c68b9070 575 np->name, HIPQUAD(np->remote_ip));
1da177e4 576
c68b9070 577 if (*cur != 0) {
1da177e4
LT
578 /* MAC address */
579 if ((delim = strchr(cur, ':')) == NULL)
580 goto parse_failed;
c68b9070
DM
581 *delim = 0;
582 np->remote_mac[0] = simple_strtol(cur, NULL, 16);
583 cur = delim + 1;
1da177e4
LT
584 if ((delim = strchr(cur, ':')) == NULL)
585 goto parse_failed;
c68b9070
DM
586 *delim = 0;
587 np->remote_mac[1] = simple_strtol(cur, NULL, 16);
588 cur = delim + 1;
1da177e4
LT
589 if ((delim = strchr(cur, ':')) == NULL)
590 goto parse_failed;
c68b9070
DM
591 *delim = 0;
592 np->remote_mac[2] = simple_strtol(cur, NULL, 16);
593 cur = delim + 1;
1da177e4
LT
594 if ((delim = strchr(cur, ':')) == NULL)
595 goto parse_failed;
c68b9070
DM
596 *delim = 0;
597 np->remote_mac[3] = simple_strtol(cur, NULL, 16);
598 cur = delim + 1;
1da177e4
LT
599 if ((delim = strchr(cur, ':')) == NULL)
600 goto parse_failed;
c68b9070
DM
601 *delim = 0;
602 np->remote_mac[4] = simple_strtol(cur, NULL, 16);
603 cur = delim + 1;
604 np->remote_mac[5] = simple_strtol(cur, NULL, 16);
1da177e4
LT
605 }
606
607 printk(KERN_INFO "%s: remote ethernet address "
608 "%02x:%02x:%02x:%02x:%02x:%02x\n",
609 np->name,
610 np->remote_mac[0],
611 np->remote_mac[1],
612 np->remote_mac[2],
613 np->remote_mac[3],
614 np->remote_mac[4],
615 np->remote_mac[5]);
616
617 return 0;
618
619 parse_failed:
620 printk(KERN_INFO "%s: couldn't parse config at %s!\n",
621 np->name, cur);
622 return -1;
623}
624
625int netpoll_setup(struct netpoll *np)
626{
627 struct net_device *ndev = NULL;
628 struct in_device *in_dev;
115c1d6e 629 struct netpoll_info *npinfo;
fbeec2e1 630 unsigned long flags;
b41848b6 631 int err;
1da177e4
LT
632
633 if (np->dev_name)
634 ndev = dev_get_by_name(np->dev_name);
635 if (!ndev) {
636 printk(KERN_ERR "%s: %s doesn't exist, aborting.\n",
637 np->name, np->dev_name);
b41848b6 638 return -ENODEV;
1da177e4
LT
639 }
640
641 np->dev = ndev;
115c1d6e
JM
642 if (!ndev->npinfo) {
643 npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
b41848b6
SH
644 if (!npinfo) {
645 err = -ENOMEM;
115c1d6e 646 goto release;
b41848b6 647 }
115c1d6e 648
11513128 649 npinfo->rx_flags = 0;
fbeec2e1 650 npinfo->rx_np = NULL;
a9f6a0dd 651 spin_lock_init(&npinfo->poll_lock);
115c1d6e 652 npinfo->poll_owner = -1;
2bdfe0ba 653
a9f6a0dd 654 spin_lock_init(&npinfo->rx_lock);
068c6e98 655 skb_queue_head_init(&npinfo->arp_tx);
b6cd27ed 656 skb_queue_head_init(&npinfo->txq);
4c1ac1b4 657 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
b6cd27ed 658
93ec2c72
SH
659 atomic_set(&npinfo->refcnt, 1);
660 } else {
115c1d6e 661 npinfo = ndev->npinfo;
93ec2c72
SH
662 atomic_inc(&npinfo->refcnt);
663 }
1da177e4
LT
664
665 if (!ndev->poll_controller) {
666 printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
667 np->name, np->dev_name);
b41848b6 668 err = -ENOTSUPP;
1da177e4
LT
669 goto release;
670 }
671
672 if (!netif_running(ndev)) {
673 unsigned long atmost, atleast;
674
675 printk(KERN_INFO "%s: device %s not up yet, forcing it\n",
676 np->name, np->dev_name);
677
6756ae4b 678 rtnl_lock();
b41848b6
SH
679 err = dev_open(ndev);
680 rtnl_unlock();
681
682 if (err) {
1da177e4 683 printk(KERN_ERR "%s: failed to open %s\n",
b41848b6 684 np->name, ndev->name);
1da177e4
LT
685 goto release;
686 }
1da177e4
LT
687
688 atleast = jiffies + HZ/10;
4ec93edb 689 atmost = jiffies + 4*HZ;
1da177e4
LT
690 while (!netif_carrier_ok(ndev)) {
691 if (time_after(jiffies, atmost)) {
692 printk(KERN_NOTICE
693 "%s: timeout waiting for carrier\n",
694 np->name);
695 break;
696 }
697 cond_resched();
698 }
699
700 /* If carrier appears to come up instantly, we don't
701 * trust it and pause so that we don't pump all our
702 * queued console messages into the bitbucket.
703 */
704
705 if (time_before(jiffies, atleast)) {
706 printk(KERN_NOTICE "%s: carrier detect appears"
707 " untrustworthy, waiting 4 seconds\n",
708 np->name);
709 msleep(4000);
710 }
711 }
712
3860288e 713 if (is_zero_ether_addr(np->local_mac) && ndev->dev_addr)
1da177e4
LT
714 memcpy(np->local_mac, ndev->dev_addr, 6);
715
716 if (!np->local_ip) {
717 rcu_read_lock();
e5ed6399 718 in_dev = __in_dev_get_rcu(ndev);
1da177e4
LT
719
720 if (!in_dev || !in_dev->ifa_list) {
721 rcu_read_unlock();
722 printk(KERN_ERR "%s: no IP address for %s, aborting\n",
723 np->name, np->dev_name);
b41848b6 724 err = -EDESTADDRREQ;
1da177e4
LT
725 goto release;
726 }
727
728 np->local_ip = ntohl(in_dev->ifa_list->ifa_local);
729 rcu_read_unlock();
730 printk(KERN_INFO "%s: local IP %d.%d.%d.%d\n",
731 np->name, HIPQUAD(np->local_ip));
732 }
733
fbeec2e1
JM
734 if (np->rx_hook) {
735 spin_lock_irqsave(&npinfo->rx_lock, flags);
736 npinfo->rx_flags |= NETPOLL_RX_ENABLED;
737 npinfo->rx_np = np;
738 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
739 }
26520765
IM
740
741 /* fill up the skb queue */
742 refill_skbs();
743
fbeec2e1 744 /* last thing to do is link it to the net device structure */
115c1d6e 745 ndev->npinfo = npinfo;
1da177e4 746
53fb95d3
MM
747 /* avoid racing with NAPI reading npinfo */
748 synchronize_rcu();
749
1da177e4
LT
750 return 0;
751
752 release:
115c1d6e
JM
753 if (!ndev->npinfo)
754 kfree(npinfo);
1da177e4
LT
755 np->dev = NULL;
756 dev_put(ndev);
b41848b6 757 return err;
1da177e4
LT
758}
759
c68b9070
DM
760static int __init netpoll_init(void)
761{
a1bcfacd
SH
762 skb_queue_head_init(&skb_pool);
763 return 0;
764}
765core_initcall(netpoll_init);
766
1da177e4
LT
767void netpoll_cleanup(struct netpoll *np)
768{
fbeec2e1
JM
769 struct netpoll_info *npinfo;
770 unsigned long flags;
771
115c1d6e 772 if (np->dev) {
fbeec2e1 773 npinfo = np->dev->npinfo;
93ec2c72
SH
774 if (npinfo) {
775 if (npinfo->rx_np == np) {
776 spin_lock_irqsave(&npinfo->rx_lock, flags);
777 npinfo->rx_np = NULL;
778 npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
779 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
780 }
781
782 np->dev->npinfo = NULL;
783 if (atomic_dec_and_test(&npinfo->refcnt)) {
784 skb_queue_purge(&npinfo->arp_tx);
4ec93edb 785 skb_queue_purge(&npinfo->txq);
6c43ff18 786 cancel_rearming_delayed_work(&npinfo->tx_work);
4ec93edb 787 flush_scheduled_work();
93ec2c72
SH
788
789 kfree(npinfo);
790 }
fbeec2e1 791 }
93ec2c72 792
115c1d6e
JM
793 dev_put(np->dev);
794 }
fbeec2e1 795
1da177e4
LT
796 np->dev = NULL;
797}
798
799int netpoll_trap(void)
800{
801 return atomic_read(&trapped);
802}
803
804void netpoll_set_trap(int trap)
805{
806 if (trap)
807 atomic_inc(&trapped);
808 else
809 atomic_dec(&trapped);
810}
811
812EXPORT_SYMBOL(netpoll_set_trap);
813EXPORT_SYMBOL(netpoll_trap);
814EXPORT_SYMBOL(netpoll_parse_options);
815EXPORT_SYMBOL(netpoll_setup);
816EXPORT_SYMBOL(netpoll_cleanup);
817EXPORT_SYMBOL(netpoll_send_udp);
818EXPORT_SYMBOL(netpoll_poll);