blob: 4581ece48bb24e1308854525306ce4a86f92c56e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020016#include <linux/if_arp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#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
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -080038static struct sk_buff_head skb_pool;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
40static atomic_t trapped;
41
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -070042#define USEC_PER_POLL 50
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#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);
Neil Horman068c6e92006-06-26 00:04:27 -070051static void arp_reply(struct sk_buff *skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
David Howellsc4028952006-11-22 14:57:56 +000053static void queue_process(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -070054{
David Howells4c1ac1b2006-12-05 14:37:56 +000055 struct netpoll_info *npinfo =
56 container_of(work, struct netpoll_info, tx_work.work);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 struct sk_buff *skb;
Ingo Molnar36405432006-12-12 17:20:42 +010058 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070060 while ((skb = skb_dequeue(&npinfo->txq))) {
61 struct net_device *dev = skb->dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -070062
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070063 if (!netif_device_present(dev) || !netif_running(dev)) {
64 __kfree_skb(skb);
65 continue;
66 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
Ingo Molnar36405432006-12-12 17:20:42 +010068 local_irq_save(flags);
69 netif_tx_lock(dev);
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070070 if (netif_queue_stopped(dev) ||
71 dev->hard_start_xmit(skb, dev) != NETDEV_TX_OK) {
72 skb_queue_head(&npinfo->txq, skb);
Ingo Molnar36405432006-12-12 17:20:42 +010073 netif_tx_unlock(dev);
74 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -070075
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070076 schedule_delayed_work(&npinfo->tx_work, HZ/10);
77 return;
78 }
Ingo Molnar36405432006-12-12 17:20:42 +010079 netif_tx_unlock(dev);
80 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 }
82}
83
Al Virob51655b2006-11-14 21:40:42 -080084static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,
85 unsigned short ulen, __be32 saddr, __be32 daddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070086{
Al Virod6f5493c2006-11-14 21:26:08 -080087 __wsum psum;
Herbert Xufb286bb2005-11-10 13:01:24 -080088
89 if (uh->check == 0 || skb->ip_summed == CHECKSUM_UNNECESSARY)
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 return 0;
91
Herbert Xufb286bb2005-11-10 13:01:24 -080092 psum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070093
Patrick McHardy84fa7932006-08-29 16:44:56 -070094 if (skb->ip_summed == CHECKSUM_COMPLETE &&
Al Virod3bc23e2006-11-14 21:24:49 -080095 !csum_fold(csum_add(psum, skb->csum)))
Herbert Xufb286bb2005-11-10 13:01:24 -080096 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
Herbert Xufb286bb2005-11-10 13:01:24 -080098 skb->csum = psum;
99
100 return __skb_checksum_complete(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101}
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{
Jeff Moyer115c1d62005-06-22 22:05:31 -0700121 struct netpoll_info *npinfo = np->dev->npinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 int budget = 16;
123
124 if (test_bit(__LINK_STATE_RX_SCHED, &np->dev->state) &&
Jeff Moyer115c1d62005-06-22 22:05:31 -0700125 npinfo->poll_owner != smp_processor_id() &&
126 spin_trylock(&npinfo->poll_lock)) {
127 npinfo->rx_flags |= NETPOLL_RX_DROP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 atomic_inc(&trapped);
129
130 np->dev->poll(np->dev, &budget);
131
132 atomic_dec(&trapped);
Jeff Moyer115c1d62005-06-22 22:05:31 -0700133 npinfo->rx_flags &= ~NETPOLL_RX_DROP;
134 spin_unlock(&npinfo->poll_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 }
136}
137
Neil Horman068c6e92006-06-26 00:04:27 -0700138static 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 }
Neil Horman068c6e92006-06-26 00:04:27 -0700151}
152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153void netpoll_poll(struct netpoll *np)
154{
David S. Millerc68b9072006-11-14 20:40:49 -0800155 if (!np->dev || !netif_running(np->dev) || !np->dev->poll_controller)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 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
Neil Horman068c6e92006-06-26 00:04:27 -0700163 service_arp_queue(np->dev->npinfo);
164
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165 zap_completion_queue();
166}
167
168static void refill_skbs(void)
169{
170 struct sk_buff *skb;
171 unsigned long flags;
172
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800173 spin_lock_irqsave(&skb_pool.lock, flags);
174 while (skb_pool.qlen < MAX_SKBS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC);
176 if (!skb)
177 break;
178
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800179 __skb_queue_tail(&skb_pool, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 }
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800181 spin_unlock_irqrestore(&skb_pool.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182}
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;
David S. Millerc68b9072006-11-14 20:40:49 -0800200 if (skb->destructor)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 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
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800210static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211{
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800212 int count = 0;
213 struct sk_buff *skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
215 zap_completion_queue();
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800216 refill_skbs();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217repeat:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218
219 skb = alloc_skb(len, GFP_ATOMIC);
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800220 if (!skb)
221 skb = skb_dequeue(&skb_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
223 if (!skb) {
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800224 if (++count < 10) {
225 netpoll_poll(np);
226 goto repeat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 }
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800228 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229 }
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{
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700238 int status = NETDEV_TX_BUSY;
239 unsigned long tries;
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900240 struct net_device *dev = np->dev;
241 struct netpoll_info *npinfo = np->dev->npinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900243 if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
244 __kfree_skb(skb);
245 return;
246 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700248 /* don't get messages out of order, and no recursion */
David S. Millerc68b9072006-11-14 20:40:49 -0800249 if (skb_queue_len(&npinfo->txq) == 0 &&
Andrew Mortone37b8d92006-12-09 14:01:49 -0800250 npinfo->poll_owner != smp_processor_id()) {
Andrew Mortona49f99f2006-12-11 17:24:46 -0800251 unsigned long flags;
252
253 local_irq_save(flags);
Andrew Mortone37b8d92006-12-09 14:01:49 -0800254 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);
Matt Mackallf0d34592005-08-11 19:25:11 -0700260
Andrew Mortone37b8d92006-12-09 14:01:49 -0800261 if (status == NETDEV_TX_OK)
262 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263
Andrew Mortone37b8d92006-12-09 14:01:49 -0800264 /* tickle device maybe there is some cleanup */
265 netpoll_poll(np);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
Andrew Mortone37b8d92006-12-09 14:01:49 -0800267 udelay(USEC_PER_POLL);
268 }
269 netif_tx_unlock(dev);
Matt Mackall0db1d6f2005-08-11 19:25:54 -0700270 }
Andrew Mortona49f99f2006-12-11 17:24:46 -0800271 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700274 if (status != NETDEV_TX_OK) {
Stephen Hemminger5de4a472006-10-26 15:46:55 -0700275 skb_queue_tail(&npinfo->txq, skb);
David Howells4c1ac1b2006-12-05 14:37:56 +0000276 schedule_delayed_work(&npinfo->tx_work,0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278}
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
Stephen Hemminger206daaf2006-10-19 23:58:23 -0700299 skb->h.uh = udph = (struct udphdr *) skb_push(skb, sizeof(*udph));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 udph->source = htons(np->local_port);
301 udph->dest = htons(np->remote_port);
302 udph->len = htons(udp_len);
303 udph->check = 0;
Chris Lalancette8e365ee2006-11-07 14:56:19 -0800304 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)
Al Viro5e57dff2006-11-20 18:08:13 -0800309 udph->check = CSUM_MANGLED_0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310
Stephen Hemminger206daaf2006-10-19 23:58:23 -0700311 skb->nh.iph = iph = (struct iphdr *)skb_push(skb, sizeof(*iph));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312
313 /* iph->version = 4; iph->ihl = 5; */
314 put_unaligned(0x45, (unsigned char *)iph);
315 iph->tos = 0;
316 put_unaligned(htons(ip_len), &(iph->tot_len));
317 iph->id = 0;
318 iph->frag_off = 0;
319 iph->ttl = 64;
320 iph->protocol = IPPROTO_UDP;
321 iph->check = 0;
322 put_unaligned(htonl(np->local_ip), &(iph->saddr));
323 put_unaligned(htonl(np->remote_ip), &(iph->daddr));
324 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
325
326 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
Stephen Hemminger206daaf2006-10-19 23:58:23 -0700327 skb->mac.raw = skb->data;
328 skb->protocol = eth->h_proto = htons(ETH_P_IP);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 memcpy(eth->h_source, np->local_mac, 6);
330 memcpy(eth->h_dest, np->remote_mac, 6);
331
332 skb->dev = np->dev;
333
334 netpoll_send_skb(np, skb);
335}
336
337static void arp_reply(struct sk_buff *skb)
338{
Jeff Moyer115c1d62005-06-22 22:05:31 -0700339 struct netpoll_info *npinfo = skb->dev->npinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 struct arphdr *arp;
341 unsigned char *arp_ptr;
342 int size, type = ARPOP_REPLY, ptype = ETH_P_ARP;
Al Viro252e3342006-11-14 20:48:11 -0800343 __be32 sip, tip;
Neil Horman47bbec02006-12-08 00:05:55 -0800344 unsigned char *sha;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 struct sk_buff *send_skb;
Jeff Moyer115c1d62005-06-22 22:05:31 -0700346 struct netpoll *np = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700348 if (npinfo->rx_np && npinfo->rx_np->dev == skb->dev)
349 np = npinfo->rx_np;
Jeff Moyer115c1d62005-06-22 22:05:31 -0700350 if (!np)
351 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352
353 /* No arp on this interface */
354 if (skb->dev->flags & IFF_NOARP)
355 return;
356
357 if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
358 (2 * skb->dev->addr_len) +
359 (2 * sizeof(u32)))))
360 return;
361
362 skb->h.raw = skb->nh.raw = skb->data;
363 arp = skb->nh.arph;
364
365 if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
366 arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
367 arp->ar_pro != htons(ETH_P_IP) ||
368 arp->ar_op != htons(ARPOP_REQUEST))
369 return;
370
Neil Horman47bbec02006-12-08 00:05:55 -0800371 arp_ptr = (unsigned char *)(arp+1);
372 /* save the location of the src hw addr */
373 sha = arp_ptr;
374 arp_ptr += skb->dev->addr_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 memcpy(&sip, arp_ptr, 4);
Neil Horman47bbec02006-12-08 00:05:55 -0800376 arp_ptr += 4;
377 /* if we actually cared about dst hw addr, it would get copied here */
378 arp_ptr += skb->dev->addr_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 memcpy(&tip, arp_ptr, 4);
380
381 /* Should we ignore arp? */
382 if (tip != htonl(np->local_ip) || LOOPBACK(tip) || MULTICAST(tip))
383 return;
384
385 size = sizeof(struct arphdr) + 2 * (skb->dev->addr_len + 4);
386 send_skb = find_skb(np, size + LL_RESERVED_SPACE(np->dev),
387 LL_RESERVED_SPACE(np->dev));
388
389 if (!send_skb)
390 return;
391
392 send_skb->nh.raw = send_skb->data;
393 arp = (struct arphdr *) skb_put(send_skb, size);
394 send_skb->dev = skb->dev;
395 send_skb->protocol = htons(ETH_P_ARP);
396
397 /* Fill the device header for the ARP frame */
398
399 if (np->dev->hard_header &&
400 np->dev->hard_header(send_skb, skb->dev, ptype,
Neil Horman47bbec02006-12-08 00:05:55 -0800401 sha, np->local_mac,
David S. Millerc68b9072006-11-14 20:40:49 -0800402 send_skb->len) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 kfree_skb(send_skb);
404 return;
405 }
406
407 /*
408 * Fill out the arp protocol part.
409 *
410 * we only support ethernet device type,
411 * which (according to RFC 1390) should always equal 1 (Ethernet).
412 */
413
414 arp->ar_hrd = htons(np->dev->type);
415 arp->ar_pro = htons(ETH_P_IP);
416 arp->ar_hln = np->dev->addr_len;
417 arp->ar_pln = 4;
418 arp->ar_op = htons(type);
419
420 arp_ptr=(unsigned char *)(arp + 1);
421 memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
422 arp_ptr += np->dev->addr_len;
423 memcpy(arp_ptr, &tip, 4);
424 arp_ptr += 4;
Neil Horman47bbec02006-12-08 00:05:55 -0800425 memcpy(arp_ptr, sha, np->dev->addr_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 arp_ptr += np->dev->addr_len;
427 memcpy(arp_ptr, &sip, 4);
428
429 netpoll_send_skb(np, send_skb);
430}
431
432int __netpoll_rx(struct sk_buff *skb)
433{
434 int proto, len, ulen;
435 struct iphdr *iph;
436 struct udphdr *uh;
Neil Horman068c6e92006-06-26 00:04:27 -0700437 struct netpoll_info *npi = skb->dev->npinfo;
438 struct netpoll *np = npi->rx_np;
439
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700440 if (!np)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441 goto out;
442 if (skb->dev->type != ARPHRD_ETHER)
443 goto out;
444
445 /* check if netpoll clients need ARP */
446 if (skb->protocol == __constant_htons(ETH_P_ARP) &&
447 atomic_read(&trapped)) {
Neil Horman068c6e92006-06-26 00:04:27 -0700448 skb_queue_tail(&npi->arp_tx, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 return 1;
450 }
451
452 proto = ntohs(eth_hdr(skb)->h_proto);
453 if (proto != ETH_P_IP)
454 goto out;
455 if (skb->pkt_type == PACKET_OTHERHOST)
456 goto out;
457 if (skb_shared(skb))
458 goto out;
459
460 iph = (struct iphdr *)skb->data;
461 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
462 goto out;
463 if (iph->ihl < 5 || iph->version != 4)
464 goto out;
465 if (!pskb_may_pull(skb, iph->ihl*4))
466 goto out;
467 if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
468 goto out;
469
470 len = ntohs(iph->tot_len);
471 if (skb->len < len || len < iph->ihl*4)
472 goto out;
473
Aubrey.Li5e7d7fa2007-04-17 12:40:20 -0700474 /*
475 * Our transport medium may have padded the buffer out.
476 * Now We trim to the true length of the frame.
477 */
478 if (pskb_trim_rcsum(skb, len))
479 goto out;
480
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 if (iph->protocol != IPPROTO_UDP)
482 goto out;
483
484 len -= iph->ihl*4;
485 uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);
486 ulen = ntohs(uh->len);
487
488 if (ulen != len)
489 goto out;
Herbert Xufb286bb2005-11-10 13:01:24 -0800490 if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 goto out;
492 if (np->local_ip && np->local_ip != ntohl(iph->daddr))
493 goto out;
494 if (np->remote_ip && np->remote_ip != ntohl(iph->saddr))
495 goto out;
496 if (np->local_port && np->local_port != ntohs(uh->dest))
497 goto out;
498
499 np->rx_hook(np, ntohs(uh->source),
500 (char *)(uh+1),
501 ulen - sizeof(struct udphdr));
502
503 kfree_skb(skb);
504 return 1;
505
506out:
507 if (atomic_read(&trapped)) {
508 kfree_skb(skb);
509 return 1;
510 }
511
512 return 0;
513}
514
515int netpoll_parse_options(struct netpoll *np, char *opt)
516{
517 char *cur=opt, *delim;
518
David S. Millerc68b9072006-11-14 20:40:49 -0800519 if (*cur != '@') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 if ((delim = strchr(cur, '@')) == NULL)
521 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800522 *delim = 0;
523 np->local_port = simple_strtol(cur, NULL, 10);
524 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525 }
526 cur++;
527 printk(KERN_INFO "%s: local port %d\n", np->name, np->local_port);
528
David S. Millerc68b9072006-11-14 20:40:49 -0800529 if (*cur != '/') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 if ((delim = strchr(cur, '/')) == NULL)
531 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800532 *delim = 0;
533 np->local_ip = ntohl(in_aton(cur));
534 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535
536 printk(KERN_INFO "%s: local IP %d.%d.%d.%d\n",
537 np->name, HIPQUAD(np->local_ip));
538 }
539 cur++;
540
David S. Millerc68b9072006-11-14 20:40:49 -0800541 if (*cur != ',') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 /* parse out dev name */
543 if ((delim = strchr(cur, ',')) == NULL)
544 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800545 *delim = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 strlcpy(np->dev_name, cur, sizeof(np->dev_name));
David S. Millerc68b9072006-11-14 20:40:49 -0800547 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 }
549 cur++;
550
551 printk(KERN_INFO "%s: interface %s\n", np->name, np->dev_name);
552
David S. Millerc68b9072006-11-14 20:40:49 -0800553 if (*cur != '@') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 /* dst port */
555 if ((delim = strchr(cur, '@')) == NULL)
556 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800557 *delim = 0;
558 np->remote_port = simple_strtol(cur, NULL, 10);
559 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 }
561 cur++;
562 printk(KERN_INFO "%s: remote port %d\n", np->name, np->remote_port);
563
564 /* dst ip */
565 if ((delim = strchr(cur, '/')) == NULL)
566 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800567 *delim = 0;
568 np->remote_ip = ntohl(in_aton(cur));
569 cur = delim + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570
571 printk(KERN_INFO "%s: remote IP %d.%d.%d.%d\n",
David S. Millerc68b9072006-11-14 20:40:49 -0800572 np->name, HIPQUAD(np->remote_ip));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573
David S. Millerc68b9072006-11-14 20:40:49 -0800574 if (*cur != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 /* MAC address */
576 if ((delim = strchr(cur, ':')) == NULL)
577 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800578 *delim = 0;
579 np->remote_mac[0] = simple_strtol(cur, NULL, 16);
580 cur = delim + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 if ((delim = strchr(cur, ':')) == NULL)
582 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800583 *delim = 0;
584 np->remote_mac[1] = simple_strtol(cur, NULL, 16);
585 cur = delim + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 if ((delim = strchr(cur, ':')) == NULL)
587 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800588 *delim = 0;
589 np->remote_mac[2] = simple_strtol(cur, NULL, 16);
590 cur = delim + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 if ((delim = strchr(cur, ':')) == NULL)
592 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800593 *delim = 0;
594 np->remote_mac[3] = simple_strtol(cur, NULL, 16);
595 cur = delim + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 if ((delim = strchr(cur, ':')) == NULL)
597 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800598 *delim = 0;
599 np->remote_mac[4] = simple_strtol(cur, NULL, 16);
600 cur = delim + 1;
601 np->remote_mac[5] = simple_strtol(cur, NULL, 16);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 }
603
604 printk(KERN_INFO "%s: remote ethernet address "
605 "%02x:%02x:%02x:%02x:%02x:%02x\n",
606 np->name,
607 np->remote_mac[0],
608 np->remote_mac[1],
609 np->remote_mac[2],
610 np->remote_mac[3],
611 np->remote_mac[4],
612 np->remote_mac[5]);
613
614 return 0;
615
616 parse_failed:
617 printk(KERN_INFO "%s: couldn't parse config at %s!\n",
618 np->name, cur);
619 return -1;
620}
621
622int netpoll_setup(struct netpoll *np)
623{
624 struct net_device *ndev = NULL;
625 struct in_device *in_dev;
Jeff Moyer115c1d62005-06-22 22:05:31 -0700626 struct netpoll_info *npinfo;
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700627 unsigned long flags;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700628 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629
630 if (np->dev_name)
631 ndev = dev_get_by_name(np->dev_name);
632 if (!ndev) {
633 printk(KERN_ERR "%s: %s doesn't exist, aborting.\n",
634 np->name, np->dev_name);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700635 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 }
637
638 np->dev = ndev;
Jeff Moyer115c1d62005-06-22 22:05:31 -0700639 if (!ndev->npinfo) {
640 npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700641 if (!npinfo) {
642 err = -ENOMEM;
Jeff Moyer115c1d62005-06-22 22:05:31 -0700643 goto release;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700644 }
Jeff Moyer115c1d62005-06-22 22:05:31 -0700645
Jeff Moyer11513122005-08-11 19:23:04 -0700646 npinfo->rx_flags = 0;
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700647 npinfo->rx_np = NULL;
Ingo Molnara9f6a0d2005-09-09 13:10:41 -0700648 spin_lock_init(&npinfo->poll_lock);
Jeff Moyer115c1d62005-06-22 22:05:31 -0700649 npinfo->poll_owner = -1;
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700650
Ingo Molnara9f6a0d2005-09-09 13:10:41 -0700651 spin_lock_init(&npinfo->rx_lock);
Neil Horman068c6e92006-06-26 00:04:27 -0700652 skb_queue_head_init(&npinfo->arp_tx);
Stephen Hemmingerb6cd27e2006-10-26 15:46:51 -0700653 skb_queue_head_init(&npinfo->txq);
David Howells4c1ac1b2006-12-05 14:37:56 +0000654 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
Stephen Hemmingerb6cd27e2006-10-26 15:46:51 -0700655
Stephen Hemminger93ec2c72006-10-26 15:46:50 -0700656 atomic_set(&npinfo->refcnt, 1);
657 } else {
Jeff Moyer115c1d62005-06-22 22:05:31 -0700658 npinfo = ndev->npinfo;
Stephen Hemminger93ec2c72006-10-26 15:46:50 -0700659 atomic_inc(&npinfo->refcnt);
660 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661
662 if (!ndev->poll_controller) {
663 printk(KERN_ERR "%s: %s doesn't support polling, aborting.\n",
664 np->name, np->dev_name);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700665 err = -ENOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 goto release;
667 }
668
669 if (!netif_running(ndev)) {
670 unsigned long atmost, atleast;
671
672 printk(KERN_INFO "%s: device %s not up yet, forcing it\n",
673 np->name, np->dev_name);
674
Stephen Hemminger6756ae42006-03-20 22:23:58 -0800675 rtnl_lock();
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700676 err = dev_open(ndev);
677 rtnl_unlock();
678
679 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 printk(KERN_ERR "%s: failed to open %s\n",
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700681 np->name, ndev->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 goto release;
683 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684
685 atleast = jiffies + HZ/10;
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900686 atmost = jiffies + 4*HZ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 while (!netif_carrier_ok(ndev)) {
688 if (time_after(jiffies, atmost)) {
689 printk(KERN_NOTICE
690 "%s: timeout waiting for carrier\n",
691 np->name);
692 break;
693 }
694 cond_resched();
695 }
696
697 /* If carrier appears to come up instantly, we don't
698 * trust it and pause so that we don't pump all our
699 * queued console messages into the bitbucket.
700 */
701
702 if (time_before(jiffies, atleast)) {
703 printk(KERN_NOTICE "%s: carrier detect appears"
704 " untrustworthy, waiting 4 seconds\n",
705 np->name);
706 msleep(4000);
707 }
708 }
709
Kris Katterjohn38602882006-01-17 15:15:38 -0800710 if (is_zero_ether_addr(np->local_mac) && ndev->dev_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 memcpy(np->local_mac, ndev->dev_addr, 6);
712
713 if (!np->local_ip) {
714 rcu_read_lock();
Herbert Xue5ed6392005-10-03 14:35:55 -0700715 in_dev = __in_dev_get_rcu(ndev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716
717 if (!in_dev || !in_dev->ifa_list) {
718 rcu_read_unlock();
719 printk(KERN_ERR "%s: no IP address for %s, aborting\n",
720 np->name, np->dev_name);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700721 err = -EDESTADDRREQ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722 goto release;
723 }
724
725 np->local_ip = ntohl(in_dev->ifa_list->ifa_local);
726 rcu_read_unlock();
727 printk(KERN_INFO "%s: local IP %d.%d.%d.%d\n",
728 np->name, HIPQUAD(np->local_ip));
729 }
730
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700731 if (np->rx_hook) {
732 spin_lock_irqsave(&npinfo->rx_lock, flags);
733 npinfo->rx_flags |= NETPOLL_RX_ENABLED;
734 npinfo->rx_np = np;
735 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
736 }
Ingo Molnar26520762005-08-11 19:26:42 -0700737
738 /* fill up the skb queue */
739 refill_skbs();
740
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700741 /* last thing to do is link it to the net device structure */
Jeff Moyer115c1d62005-06-22 22:05:31 -0700742 ndev->npinfo = npinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743
Matt Mackall53fb95d2005-08-11 19:27:43 -0700744 /* avoid racing with NAPI reading npinfo */
745 synchronize_rcu();
746
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 return 0;
748
749 release:
Jeff Moyer115c1d62005-06-22 22:05:31 -0700750 if (!ndev->npinfo)
751 kfree(npinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 np->dev = NULL;
753 dev_put(ndev);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700754 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755}
756
David S. Millerc68b9072006-11-14 20:40:49 -0800757static int __init netpoll_init(void)
758{
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800759 skb_queue_head_init(&skb_pool);
760 return 0;
761}
762core_initcall(netpoll_init);
763
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764void netpoll_cleanup(struct netpoll *np)
765{
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700766 struct netpoll_info *npinfo;
767 unsigned long flags;
768
Jeff Moyer115c1d62005-06-22 22:05:31 -0700769 if (np->dev) {
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700770 npinfo = np->dev->npinfo;
Stephen Hemminger93ec2c72006-10-26 15:46:50 -0700771 if (npinfo) {
772 if (npinfo->rx_np == np) {
773 spin_lock_irqsave(&npinfo->rx_lock, flags);
774 npinfo->rx_np = NULL;
775 npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
776 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
777 }
778
779 np->dev->npinfo = NULL;
780 if (atomic_dec_and_test(&npinfo->refcnt)) {
781 skb_queue_purge(&npinfo->arp_tx);
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900782 skb_queue_purge(&npinfo->txq);
Stephen Hemminger6c43ff12006-10-26 15:46:53 -0700783 cancel_rearming_delayed_work(&npinfo->tx_work);
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900784 flush_scheduled_work();
Stephen Hemminger93ec2c72006-10-26 15:46:50 -0700785
786 kfree(npinfo);
787 }
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700788 }
Stephen Hemminger93ec2c72006-10-26 15:46:50 -0700789
Jeff Moyer115c1d62005-06-22 22:05:31 -0700790 dev_put(np->dev);
791 }
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700792
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 np->dev = NULL;
794}
795
796int netpoll_trap(void)
797{
798 return atomic_read(&trapped);
799}
800
801void netpoll_set_trap(int trap)
802{
803 if (trap)
804 atomic_inc(&trapped);
805 else
806 atomic_dec(&trapped);
807}
808
809EXPORT_SYMBOL(netpoll_set_trap);
810EXPORT_SYMBOL(netpoll_trap);
811EXPORT_SYMBOL(netpoll_parse_options);
812EXPORT_SYMBOL(netpoll_setup);
813EXPORT_SYMBOL(netpoll_cleanup);
814EXPORT_SYMBOL(netpoll_send_udp);
815EXPORT_SYMBOL(netpoll_poll);