blob: 3151acf5ec13afb34480a28a3f4a73deae69990a [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
Joe Perchese6ec269352012-01-29 15:50:43 +000012#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
Anton Vorontsovbff38772009-07-08 11:10:56 -070014#include <linux/moduleparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/netdevice.h>
16#include <linux/etherdevice.h>
17#include <linux/string.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020018#include <linux/if_arp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/inetdevice.h>
20#include <linux/inet.h>
21#include <linux/interrupt.h>
22#include <linux/netpoll.h>
23#include <linux/sched.h>
24#include <linux/delay.h>
25#include <linux/rcupdate.h>
26#include <linux/workqueue.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090027#include <linux/slab.h>
Paul Gortmakerbc3b2d72011-07-15 11:47:34 -040028#include <linux/export.h>
Amerigo Wang689971b2012-08-10 01:24:49 +000029#include <linux/if_vlan.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <net/tcp.h>
31#include <net/udp.h>
32#include <asm/unaligned.h>
David S. Miller9cbc1cb2009-06-15 03:02:23 -070033#include <trace/events/napi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
35/*
36 * We maintain a small pool of fully-sized skbs, to make sure the
37 * message gets out even in extreme OOM situations.
38 */
39
40#define MAX_UDP_CHUNK 1460
41#define MAX_SKBS 32
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -080043static struct sk_buff_head skb_pool;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
45static atomic_t trapped;
46
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -070047#define USEC_PER_POLL 50
David S. Millerd9452e92008-03-04 12:28:49 -080048#define NETPOLL_RX_ENABLED 1
49#define NETPOLL_RX_DROP 2
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Joe Perches6f706242012-01-29 15:50:44 +000051#define MAX_SKB_SIZE \
52 (sizeof(struct ethhdr) + \
53 sizeof(struct iphdr) + \
54 sizeof(struct udphdr) + \
55 MAX_UDP_CHUNK)
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
David S. Miller3578b0c2010-08-03 00:24:04 -070057static void zap_completion_queue(void);
Amerigo Wang28996562012-08-10 01:24:42 +000058static void netpoll_arp_reply(struct sk_buff *skb, struct netpoll_info *npinfo);
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
Anton Vorontsovbff38772009-07-08 11:10:56 -070060static unsigned int carrier_timeout = 4;
61module_param(carrier_timeout, uint, 0644);
62
Joe Perchese6ec269352012-01-29 15:50:43 +000063#define np_info(np, fmt, ...) \
64 pr_info("%s: " fmt, np->name, ##__VA_ARGS__)
65#define np_err(np, fmt, ...) \
66 pr_err("%s: " fmt, np->name, ##__VA_ARGS__)
67#define np_notice(np, fmt, ...) \
68 pr_notice("%s: " fmt, np->name, ##__VA_ARGS__)
69
David Howellsc4028952006-11-22 14:57:56 +000070static void queue_process(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -070071{
David Howells4c1ac1b2006-12-05 14:37:56 +000072 struct netpoll_info *npinfo =
73 container_of(work, struct netpoll_info, tx_work.work);
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 struct sk_buff *skb;
Ingo Molnar36405432006-12-12 17:20:42 +010075 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070077 while ((skb = skb_dequeue(&npinfo->txq))) {
78 struct net_device *dev = skb->dev;
Stephen Hemminger00829822008-11-20 20:14:53 -080079 const struct net_device_ops *ops = dev->netdev_ops;
David S. Millerfd2ea0a2008-07-17 01:56:23 -070080 struct netdev_queue *txq;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070082 if (!netif_device_present(dev) || !netif_running(dev)) {
83 __kfree_skb(skb);
84 continue;
85 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070086
David S. Millerfd2ea0a2008-07-17 01:56:23 -070087 txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
88
Ingo Molnar36405432006-12-12 17:20:42 +010089 local_irq_save(flags);
David S. Millerfd2ea0a2008-07-17 01:56:23 -070090 __netif_tx_lock(txq, smp_processor_id());
Tom Herbert734664982011-11-28 16:32:44 +000091 if (netif_xmit_frozen_or_stopped(txq) ||
Stephen Hemminger00829822008-11-20 20:14:53 -080092 ops->ndo_start_xmit(skb, dev) != NETDEV_TX_OK) {
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070093 skb_queue_head(&npinfo->txq, skb);
David S. Millerfd2ea0a2008-07-17 01:56:23 -070094 __netif_tx_unlock(txq);
Ingo Molnar36405432006-12-12 17:20:42 +010095 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Jarek Poplawski25442ca2007-07-05 17:42:44 -070097 schedule_delayed_work(&npinfo->tx_work, HZ/10);
Stephen Hemminger6c43ff12006-10-26 15:46:53 -070098 return;
99 }
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700100 __netif_tx_unlock(txq);
Ingo Molnar36405432006-12-12 17:20:42 +0100101 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 }
103}
104
Al Virob51655b2006-11-14 21:40:42 -0800105static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,
106 unsigned short ulen, __be32 saddr, __be32 daddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107{
Al Virod6f5493c2006-11-14 21:26:08 -0800108 __wsum psum;
Herbert Xufb286bb2005-11-10 13:01:24 -0800109
Herbert Xu60476372007-04-09 11:59:39 -0700110 if (uh->check == 0 || skb_csum_unnecessary(skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 return 0;
112
Herbert Xufb286bb2005-11-10 13:01:24 -0800113 psum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114
Patrick McHardy84fa7932006-08-29 16:44:56 -0700115 if (skb->ip_summed == CHECKSUM_COMPLETE &&
Al Virod3bc23e2006-11-14 21:24:49 -0800116 !csum_fold(csum_add(psum, skb->csum)))
Herbert Xufb286bb2005-11-10 13:01:24 -0800117 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118
Herbert Xufb286bb2005-11-10 13:01:24 -0800119 skb->csum = psum;
120
121 return __skb_checksum_complete(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122}
123
124/*
125 * Check whether delayed processing was scheduled for our NIC. If so,
126 * we attempt to grab the poll lock and use ->poll() to pump the card.
127 * If this fails, either we've recursed in ->poll() or it's already
128 * running on another CPU.
129 *
130 * Note: we don't mask interrupts with this lock because we're using
131 * trylock here and interrupts are already disabled in the softirq
132 * case. Further, we test the poll_owner to avoid recursion on UP
133 * systems where the lock doesn't exist.
134 *
135 * In cases where there is bi-directional communications, reading only
136 * one message at a time can lead to packets being dropped by the
137 * network adapter, forcing superfluous retries and possibly timeouts.
138 * Thus, we set our budget to greater than 1.
139 */
David S. Miller0a7606c2007-10-29 21:28:47 -0700140static int poll_one_napi(struct netpoll_info *npinfo,
141 struct napi_struct *napi, int budget)
142{
143 int work;
144
145 /* net_rx_action's ->poll() invocations and our's are
146 * synchronized by this test which is only made while
147 * holding the napi->poll_lock.
148 */
149 if (!test_bit(NAPI_STATE_SCHED, &napi->state))
150 return budget;
151
David S. Millerd9452e92008-03-04 12:28:49 -0800152 npinfo->rx_flags |= NETPOLL_RX_DROP;
David S. Miller0a7606c2007-10-29 21:28:47 -0700153 atomic_inc(&trapped);
Neil Horman7b363e42008-12-09 23:22:26 -0800154 set_bit(NAPI_STATE_NPSVC, &napi->state);
David S. Miller0a7606c2007-10-29 21:28:47 -0700155
156 work = napi->poll(napi, budget);
David S. Miller7d18f112009-05-21 23:30:09 -0700157 trace_napi_poll(napi);
David S. Miller0a7606c2007-10-29 21:28:47 -0700158
Neil Horman7b363e42008-12-09 23:22:26 -0800159 clear_bit(NAPI_STATE_NPSVC, &napi->state);
David S. Miller0a7606c2007-10-29 21:28:47 -0700160 atomic_dec(&trapped);
David S. Millerd9452e92008-03-04 12:28:49 -0800161 npinfo->rx_flags &= ~NETPOLL_RX_DROP;
David S. Miller0a7606c2007-10-29 21:28:47 -0700162
163 return budget - work;
164}
165
Stephen Hemminger51069302007-11-19 19:18:11 -0800166static void poll_napi(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167{
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700168 struct napi_struct *napi;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 int budget = 16;
170
Neil Hormanf13d4932010-10-19 07:04:26 +0000171 list_for_each_entry(napi, &dev->napi_list, dev_list) {
David S. Miller0a7606c2007-10-29 21:28:47 -0700172 if (napi->poll_owner != smp_processor_id() &&
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700173 spin_trylock(&napi->poll_lock)) {
Amerigo Wang28996562012-08-10 01:24:42 +0000174 budget = poll_one_napi(rcu_dereference_bh(dev->npinfo),
175 napi, budget);
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700176 spin_unlock(&napi->poll_lock);
David S. Miller0a7606c2007-10-29 21:28:47 -0700177
Amerigo Wang072a9c42012-08-24 21:41:11 +0000178 if (!budget)
David S. Miller0a7606c2007-10-29 21:28:47 -0700179 break;
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700180 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 }
182}
183
Neil Horman068c6e92006-06-26 00:04:27 -0700184static void service_arp_queue(struct netpoll_info *npi)
185{
Stephen Hemminger51069302007-11-19 19:18:11 -0800186 if (npi) {
187 struct sk_buff *skb;
Neil Horman068c6e92006-06-26 00:04:27 -0700188
Stephen Hemminger51069302007-11-19 19:18:11 -0800189 while ((skb = skb_dequeue(&npi->arp_tx)))
Amerigo Wang28996562012-08-10 01:24:42 +0000190 netpoll_arp_reply(skb, npi);
Neil Horman068c6e92006-06-26 00:04:27 -0700191 }
Neil Horman068c6e92006-06-26 00:04:27 -0700192}
193
Joe Perches234b9212011-06-30 15:08:57 +0000194static void netpoll_poll_dev(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195{
Pavel Emelyanov5e392732009-05-11 00:36:35 +0000196 const struct net_device_ops *ops;
Amerigo Wang28996562012-08-10 01:24:42 +0000197 struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo);
Stephen Hemminger51069302007-11-19 19:18:11 -0800198
Pavel Emelyanov5e392732009-05-11 00:36:35 +0000199 if (!dev || !netif_running(dev))
200 return;
201
202 ops = dev->netdev_ops;
203 if (!ops->ndo_poll_controller)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 return;
205
206 /* Process pending work on NIC */
Stephen Hemmingerd3147742008-11-19 21:32:24 -0800207 ops->ndo_poll_controller(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
Stephen Hemminger51069302007-11-19 19:18:11 -0800209 poll_napi(dev);
210
Eric Dumazet58e05f32012-02-14 10:11:59 +0000211 if (dev->flags & IFF_SLAVE) {
Amerigo Wang28996562012-08-10 01:24:42 +0000212 if (ni) {
Amerigo Wang5a698af2011-02-17 23:43:34 +0000213 struct net_device *bond_dev = dev->master;
214 struct sk_buff *skb;
Amerigo Wang28996562012-08-10 01:24:42 +0000215 struct netpoll_info *bond_ni = rcu_dereference_bh(bond_dev->npinfo);
216 while ((skb = skb_dequeue(&ni->arp_tx))) {
Amerigo Wang5a698af2011-02-17 23:43:34 +0000217 skb->dev = bond_dev;
Amerigo Wang28996562012-08-10 01:24:42 +0000218 skb_queue_tail(&bond_ni->arp_tx, skb);
Amerigo Wang5a698af2011-02-17 23:43:34 +0000219 }
220 }
221 }
222
Amerigo Wang28996562012-08-10 01:24:42 +0000223 service_arp_queue(ni);
Neil Horman068c6e92006-06-26 00:04:27 -0700224
David S. Miller3578b0c2010-08-03 00:24:04 -0700225 zap_completion_queue();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226}
227
228static void refill_skbs(void)
229{
230 struct sk_buff *skb;
231 unsigned long flags;
232
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800233 spin_lock_irqsave(&skb_pool.lock, flags);
234 while (skb_pool.qlen < MAX_SKBS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC);
236 if (!skb)
237 break;
238
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800239 __skb_queue_tail(&skb_pool, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 }
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800241 spin_unlock_irqrestore(&skb_pool.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242}
243
David S. Miller3578b0c2010-08-03 00:24:04 -0700244static void zap_completion_queue(void)
245{
246 unsigned long flags;
247 struct softnet_data *sd = &get_cpu_var(softnet_data);
248
249 if (sd->completion_queue) {
250 struct sk_buff *clist;
251
252 local_irq_save(flags);
253 clist = sd->completion_queue;
254 sd->completion_queue = NULL;
255 local_irq_restore(flags);
256
257 while (clist != NULL) {
258 struct sk_buff *skb = clist;
259 clist = clist->next;
260 if (skb->destructor) {
261 atomic_inc(&skb->users);
262 dev_kfree_skb_any(skb); /* put this one back */
263 } else {
264 __kfree_skb(skb);
265 }
266 }
267 }
268
269 put_cpu_var(softnet_data);
270}
271
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800272static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273{
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800274 int count = 0;
275 struct sk_buff *skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276
David S. Miller3578b0c2010-08-03 00:24:04 -0700277 zap_completion_queue();
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800278 refill_skbs();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279repeat:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280
281 skb = alloc_skb(len, GFP_ATOMIC);
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800282 if (!skb)
283 skb = skb_dequeue(&skb_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284
285 if (!skb) {
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800286 if (++count < 10) {
Joe Perches2a49e002011-06-30 15:08:58 +0000287 netpoll_poll_dev(np->dev);
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800288 goto repeat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 }
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800290 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 }
292
293 atomic_set(&skb->users, 1);
294 skb_reserve(skb, reserve);
295 return skb;
296}
297
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700298static int netpoll_owner_active(struct net_device *dev)
299{
300 struct napi_struct *napi;
301
302 list_for_each_entry(napi, &dev->napi_list, dev_list) {
303 if (napi->poll_owner == smp_processor_id())
304 return 1;
305 }
306 return 0;
307}
308
Amerigo Wang28996562012-08-10 01:24:42 +0000309/* call with IRQ disabled */
Neil Hormanc2355e12010-10-13 16:01:49 +0000310void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
311 struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312{
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700313 int status = NETDEV_TX_BUSY;
314 unsigned long tries;
Stephen Hemminger00829822008-11-20 20:14:53 -0800315 const struct net_device_ops *ops = dev->netdev_ops;
Herbert Xude85d992010-06-10 16:12:44 +0000316 /* It is up to the caller to keep npinfo alive. */
Amerigo Wang28996562012-08-10 01:24:42 +0000317 struct netpoll_info *npinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318
Amerigo Wang28996562012-08-10 01:24:42 +0000319 WARN_ON_ONCE(!irqs_disabled());
320
321 npinfo = rcu_dereference_bh(np->dev->npinfo);
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900322 if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
323 __kfree_skb(skb);
324 return;
325 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700327 /* don't get messages out of order, and no recursion */
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700328 if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) {
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700329 struct netdev_queue *txq;
Andrew Mortona49f99f2006-12-11 17:24:46 -0800330
Amerigo Wang8c4c49d2012-09-17 20:16:31 +0000331 txq = netdev_pick_tx(dev, skb);
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700332
Stephen Hemminger0db3dc72007-06-27 00:39:42 -0700333 /* try until next clock tick */
334 for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
335 tries > 0; --tries) {
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700336 if (__netif_tx_trylock(txq)) {
Tom Herbert734664982011-11-28 16:32:44 +0000337 if (!netif_xmit_stopped(txq)) {
Amerigo Wang689971b2012-08-10 01:24:49 +0000338 if (vlan_tx_tag_present(skb) &&
339 !(netif_skb_features(skb) & NETIF_F_HW_VLAN_TX)) {
340 skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb));
341 if (unlikely(!skb))
342 break;
343 skb->vlan_tci = 0;
344 }
345
Stephen Hemminger00829822008-11-20 20:14:53 -0800346 status = ops->ndo_start_xmit(skb, dev);
Eric Dumazet08baf562009-05-25 22:58:01 -0700347 if (status == NETDEV_TX_OK)
348 txq_trans_update(txq);
349 }
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700350 __netif_tx_unlock(txq);
Matt Mackallf0d34592005-08-11 19:25:11 -0700351
Andrew Mortone37b8d92006-12-09 14:01:49 -0800352 if (status == NETDEV_TX_OK)
353 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354
Andrew Mortone37b8d92006-12-09 14:01:49 -0800355 }
Stephen Hemminger0db3dc72007-06-27 00:39:42 -0700356
357 /* tickle device maybe there is some cleanup */
Joe Perches2a49e002011-06-30 15:08:58 +0000358 netpoll_poll_dev(np->dev);
Stephen Hemminger0db3dc72007-06-27 00:39:42 -0700359
360 udelay(USEC_PER_POLL);
Matt Mackall0db1d6f2005-08-11 19:25:54 -0700361 }
Dongdong Deng79b1bee2009-08-21 03:33:36 +0000362
363 WARN_ONCE(!irqs_disabled(),
Amerigo Wang28996562012-08-10 01:24:42 +0000364 "netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pF)\n",
Dongdong Deng79b1bee2009-08-21 03:33:36 +0000365 dev->name, ops->ndo_start_xmit);
366
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700369 if (status != NETDEV_TX_OK) {
Stephen Hemminger5de4a472006-10-26 15:46:55 -0700370 skb_queue_tail(&npinfo->txq, skb);
David Howells4c1ac1b2006-12-05 14:37:56 +0000371 schedule_delayed_work(&npinfo->tx_work,0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373}
Neil Hormanc2355e12010-10-13 16:01:49 +0000374EXPORT_SYMBOL(netpoll_send_skb_on_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375
376void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
377{
Eric Dumazet954fba02012-06-12 19:30:21 +0000378 int total_len, ip_len, udp_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 struct sk_buff *skb;
380 struct udphdr *udph;
381 struct iphdr *iph;
382 struct ethhdr *eth;
Eric Dumazetee130402012-08-24 01:47:26 +0000383 static atomic_t ip_ident;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384
385 udp_len = len + sizeof(*udph);
Eric Dumazet954fba02012-06-12 19:30:21 +0000386 ip_len = udp_len + sizeof(*iph);
387 total_len = ip_len + LL_RESERVED_SPACE(np->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388
Eric Dumazet954fba02012-06-12 19:30:21 +0000389 skb = find_skb(np, total_len + np->dev->needed_tailroom,
390 total_len - len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 if (!skb)
392 return;
393
Arnaldo Carvalho de Melo27d7ff42007-03-31 11:55:19 -0300394 skb_copy_to_linear_data(skb, msg, len);
Eric Dumazet954fba02012-06-12 19:30:21 +0000395 skb_put(skb, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396
Arnaldo Carvalho de Melo4bedb452007-03-13 14:28:48 -0300397 skb_push(skb, sizeof(*udph));
398 skb_reset_transport_header(skb);
399 udph = udp_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 udph->source = htons(np->local_port);
401 udph->dest = htons(np->remote_port);
402 udph->len = htons(udp_len);
403 udph->check = 0;
Harvey Harrisone7557af2009-03-28 15:38:31 +0000404 udph->check = csum_tcpudp_magic(np->local_ip,
405 np->remote_ip,
Chris Lalancette8e365ee2006-11-07 14:56:19 -0800406 udp_len, IPPROTO_UDP,
Joe Perches07f07572008-11-19 15:44:53 -0800407 csum_partial(udph, udp_len, 0));
Chris Lalancette8e365ee2006-11-07 14:56:19 -0800408 if (udph->check == 0)
Al Viro5e57dff2006-11-20 18:08:13 -0800409 udph->check = CSUM_MANGLED_0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -0700411 skb_push(skb, sizeof(*iph));
412 skb_reset_network_header(skb);
Arnaldo Carvalho de Meloeddc9ec2007-04-20 22:47:35 -0700413 iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414
415 /* iph->version = 4; iph->ihl = 5; */
416 put_unaligned(0x45, (unsigned char *)iph);
417 iph->tos = 0;
418 put_unaligned(htons(ip_len), &(iph->tot_len));
Eric Dumazetee130402012-08-24 01:47:26 +0000419 iph->id = htons(atomic_inc_return(&ip_ident));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 iph->frag_off = 0;
421 iph->ttl = 64;
422 iph->protocol = IPPROTO_UDP;
423 iph->check = 0;
Harvey Harrisone7557af2009-03-28 15:38:31 +0000424 put_unaligned(np->local_ip, &(iph->saddr));
425 put_unaligned(np->remote_ip, &(iph->daddr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
427
428 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
Arnaldo Carvalho de Melo459a98e2007-03-19 15:30:44 -0700429 skb_reset_mac_header(skb);
Stephen Hemminger206daaf2006-10-19 23:58:23 -0700430 skb->protocol = eth->h_proto = htons(ETH_P_IP);
Stephen Hemminger09538642007-11-19 19:23:29 -0800431 memcpy(eth->h_source, np->dev->dev_addr, ETH_ALEN);
432 memcpy(eth->h_dest, np->remote_mac, ETH_ALEN);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433
434 skb->dev = np->dev;
435
436 netpoll_send_skb(np, skb);
437}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000438EXPORT_SYMBOL(netpoll_send_udp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439
Amerigo Wang28996562012-08-10 01:24:42 +0000440static void netpoll_arp_reply(struct sk_buff *skb, struct netpoll_info *npinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441{
442 struct arphdr *arp;
443 unsigned char *arp_ptr;
444 int size, type = ARPOP_REPLY, ptype = ETH_P_ARP;
Al Viro252e3342006-11-14 20:48:11 -0800445 __be32 sip, tip;
Neil Horman47bbec02006-12-08 00:05:55 -0800446 unsigned char *sha;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 struct sk_buff *send_skb;
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000448 struct netpoll *np, *tmp;
449 unsigned long flags;
Herbert Xuae641942011-11-18 02:20:04 +0000450 int hlen, tlen;
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000451 int hits = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000453 if (list_empty(&npinfo->rx_np))
454 return;
455
456 /* Before checking the packet, we do some early
457 inspection whether this is interesting at all */
458 spin_lock_irqsave(&npinfo->rx_lock, flags);
459 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
460 if (np->dev == skb->dev)
461 hits++;
462 }
463 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
464
465 /* No netpoll struct is using this dev */
466 if (!hits)
Jeff Moyer115c1d62005-06-22 22:05:31 -0700467 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468
469 /* No arp on this interface */
470 if (skb->dev->flags & IFF_NOARP)
471 return;
472
Pavel Emelyanov988b7052008-03-03 12:20:57 -0800473 if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 return;
475
Arnaldo Carvalho de Meloc1d2bbe2007-04-10 20:45:18 -0700476 skb_reset_network_header(skb);
Arnaldo Carvalho de Melobadff6d2007-03-13 13:06:52 -0300477 skb_reset_transport_header(skb);
Arnaldo Carvalho de Melod0a92be2007-03-12 20:56:31 -0300478 arp = arp_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479
480 if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
481 arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
482 arp->ar_pro != htons(ETH_P_IP) ||
483 arp->ar_op != htons(ARPOP_REQUEST))
484 return;
485
Neil Horman47bbec02006-12-08 00:05:55 -0800486 arp_ptr = (unsigned char *)(arp+1);
487 /* save the location of the src hw addr */
488 sha = arp_ptr;
489 arp_ptr += skb->dev->addr_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 memcpy(&sip, arp_ptr, 4);
Neil Horman47bbec02006-12-08 00:05:55 -0800491 arp_ptr += 4;
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000492 /* If we actually cared about dst hw addr,
493 it would get copied here */
Neil Horman47bbec02006-12-08 00:05:55 -0800494 arp_ptr += skb->dev->addr_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 memcpy(&tip, arp_ptr, 4);
496
497 /* Should we ignore arp? */
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000498 if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 return;
500
Pavel Emelyanov988b7052008-03-03 12:20:57 -0800501 size = arp_hdr_len(skb->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000503 spin_lock_irqsave(&npinfo->rx_lock, flags);
504 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
505 if (tip != np->local_ip)
506 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507
Herbert Xuae641942011-11-18 02:20:04 +0000508 hlen = LL_RESERVED_SPACE(np->dev);
509 tlen = np->dev->needed_tailroom;
510 send_skb = find_skb(np, size + hlen + tlen, hlen);
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000511 if (!send_skb)
512 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000514 skb_reset_network_header(send_skb);
515 arp = (struct arphdr *) skb_put(send_skb, size);
516 send_skb->dev = skb->dev;
517 send_skb->protocol = htons(ETH_P_ARP);
518
519 /* Fill the device header for the ARP frame */
520 if (dev_hard_header(send_skb, skb->dev, ptype,
521 sha, np->dev->dev_addr,
522 send_skb->len) < 0) {
523 kfree_skb(send_skb);
524 continue;
525 }
526
527 /*
528 * Fill out the arp protocol part.
529 *
530 * we only support ethernet device type,
531 * which (according to RFC 1390) should
532 * always equal 1 (Ethernet).
533 */
534
535 arp->ar_hrd = htons(np->dev->type);
536 arp->ar_pro = htons(ETH_P_IP);
537 arp->ar_hln = np->dev->addr_len;
538 arp->ar_pln = 4;
539 arp->ar_op = htons(type);
540
541 arp_ptr = (unsigned char *)(arp + 1);
542 memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
543 arp_ptr += np->dev->addr_len;
544 memcpy(arp_ptr, &tip, 4);
545 arp_ptr += 4;
546 memcpy(arp_ptr, sha, np->dev->addr_len);
547 arp_ptr += np->dev->addr_len;
548 memcpy(arp_ptr, &sip, 4);
549
550 netpoll_send_skb(np, send_skb);
551
552 /* If there are several rx_hooks for the same address,
553 we're fine by sending a single reply */
554 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 }
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000556 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557}
558
Amerigo Wang57c5d462012-08-10 01:24:40 +0000559int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560{
561 int proto, len, ulen;
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000562 int hits = 0;
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000563 const struct iphdr *iph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 struct udphdr *uh;
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000565 struct netpoll *np, *tmp;
Neil Horman068c6e92006-06-26 00:04:27 -0700566
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000567 if (list_empty(&npinfo->rx_np))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 goto out;
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000569
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 if (skb->dev->type != ARPHRD_ETHER)
571 goto out;
572
David S. Millerd9452e92008-03-04 12:28:49 -0800573 /* check if netpoll clients need ARP */
YOSHIFUJI Hideaki724800d2007-03-25 20:13:04 -0700574 if (skb->protocol == htons(ETH_P_ARP) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 atomic_read(&trapped)) {
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000576 skb_queue_tail(&npinfo->arp_tx, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 return 1;
578 }
579
Amerigo Wang689971b2012-08-10 01:24:49 +0000580 if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
581 skb = vlan_untag(skb);
582 if (unlikely(!skb))
583 goto out;
584 }
585
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 proto = ntohs(eth_hdr(skb)->h_proto);
587 if (proto != ETH_P_IP)
588 goto out;
589 if (skb->pkt_type == PACKET_OTHERHOST)
590 goto out;
591 if (skb_shared(skb))
592 goto out;
593
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
595 goto out;
Eric Dumazete9278a42011-08-26 06:26:15 +0000596 iph = (struct iphdr *)skb->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 if (iph->ihl < 5 || iph->version != 4)
598 goto out;
599 if (!pskb_may_pull(skb, iph->ihl*4))
600 goto out;
Eric Dumazete9278a42011-08-26 06:26:15 +0000601 iph = (struct iphdr *)skb->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
603 goto out;
604
605 len = ntohs(iph->tot_len);
606 if (skb->len < len || len < iph->ihl*4)
607 goto out;
608
Aubrey.Li5e7d7fa2007-04-17 12:40:20 -0700609 /*
610 * Our transport medium may have padded the buffer out.
611 * Now We trim to the true length of the frame.
612 */
613 if (pskb_trim_rcsum(skb, len))
614 goto out;
615
Eric Dumazete9278a42011-08-26 06:26:15 +0000616 iph = (struct iphdr *)skb->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 if (iph->protocol != IPPROTO_UDP)
618 goto out;
619
620 len -= iph->ihl*4;
621 uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);
622 ulen = ntohs(uh->len);
623
624 if (ulen != len)
625 goto out;
Herbert Xufb286bb2005-11-10 13:01:24 -0800626 if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628
Daniel Borkmann508e14b2010-01-12 14:27:30 +0000629 list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
630 if (np->local_ip && np->local_ip != iph->daddr)
631 continue;
632 if (np->remote_ip && np->remote_ip != iph->saddr)
633 continue;
634 if (np->local_port && np->local_port != ntohs(uh->dest))
635 continue;
636
637 np->rx_hook(np, ntohs(uh->source),
638 (char *)(uh+1),
639 ulen - sizeof(struct udphdr));
640 hits++;
641 }
642
643 if (!hits)
644 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645
646 kfree_skb(skb);
647 return 1;
648
649out:
650 if (atomic_read(&trapped)) {
651 kfree_skb(skb);
652 return 1;
653 }
654
655 return 0;
656}
657
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700658void netpoll_print_options(struct netpoll *np)
659{
Joe Perchese6ec269352012-01-29 15:50:43 +0000660 np_info(np, "local port %d\n", np->local_port);
661 np_info(np, "local IP %pI4\n", &np->local_ip);
662 np_info(np, "interface '%s'\n", np->dev_name);
663 np_info(np, "remote port %d\n", np->remote_port);
664 np_info(np, "remote IP %pI4\n", &np->remote_ip);
665 np_info(np, "remote ethernet address %pM\n", np->remote_mac);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700666}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000667EXPORT_SYMBOL(netpoll_print_options);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700668
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669int netpoll_parse_options(struct netpoll *np, char *opt)
670{
671 char *cur=opt, *delim;
672
David S. Millerc68b9072006-11-14 20:40:49 -0800673 if (*cur != '@') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 if ((delim = strchr(cur, '@')) == NULL)
675 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800676 *delim = 0;
Abhijit Pawar4b5511e2012-12-09 23:12:28 +0000677 if (kstrtou16(cur, 10, &np->local_port))
678 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800679 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 }
681 cur++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682
David S. Millerc68b9072006-11-14 20:40:49 -0800683 if (*cur != '/') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 if ((delim = strchr(cur, '/')) == NULL)
685 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800686 *delim = 0;
Harvey Harrisone7557af2009-03-28 15:38:31 +0000687 np->local_ip = in_aton(cur);
David S. Millerc68b9072006-11-14 20:40:49 -0800688 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 }
690 cur++;
691
David S. Millerc68b9072006-11-14 20:40:49 -0800692 if (*cur != ',') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693 /* parse out dev name */
694 if ((delim = strchr(cur, ',')) == NULL)
695 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800696 *delim = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 strlcpy(np->dev_name, cur, sizeof(np->dev_name));
David S. Millerc68b9072006-11-14 20:40:49 -0800698 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 }
700 cur++;
701
David S. Millerc68b9072006-11-14 20:40:49 -0800702 if (*cur != '@') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 /* dst port */
704 if ((delim = strchr(cur, '@')) == NULL)
705 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800706 *delim = 0;
Amerigo Wang5fc05f82010-03-21 22:59:58 +0000707 if (*cur == ' ' || *cur == '\t')
Joe Perchese6ec269352012-01-29 15:50:43 +0000708 np_info(np, "warning: whitespace is not allowed\n");
Abhijit Pawar4b5511e2012-12-09 23:12:28 +0000709 if (kstrtou16(cur, 10, &np->remote_port))
710 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800711 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712 }
713 cur++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714
715 /* dst ip */
716 if ((delim = strchr(cur, '/')) == NULL)
717 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800718 *delim = 0;
Harvey Harrisone7557af2009-03-28 15:38:31 +0000719 np->remote_ip = in_aton(cur);
David S. Millerc68b9072006-11-14 20:40:49 -0800720 cur = delim + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721
David S. Millerc68b9072006-11-14 20:40:49 -0800722 if (*cur != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723 /* MAC address */
Alexey Dobriyan4940fc82011-05-07 23:00:07 +0000724 if (!mac_pton(cur, np->remote_mac))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 goto parse_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 }
727
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700728 netpoll_print_options(np);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729
730 return 0;
731
732 parse_failed:
Joe Perchese6ec269352012-01-29 15:50:43 +0000733 np_info(np, "couldn't parse config at '%s'!\n", cur);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 return -1;
735}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000736EXPORT_SYMBOL(netpoll_parse_options);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737
Amerigo Wang47be03a22012-08-10 01:24:37 +0000738int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp)
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000739{
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000740 struct netpoll_info *npinfo;
741 const struct net_device_ops *ops;
742 unsigned long flags;
743 int err;
744
Jiri Pirko30fdd8a02012-07-17 05:22:35 +0000745 np->dev = ndev;
746 strlcpy(np->dev_name, ndev->name, IFNAMSIZ);
747
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000748 if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
749 !ndev->netdev_ops->ndo_poll_controller) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000750 np_err(np, "%s doesn't support polling, aborting\n",
751 np->dev_name);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000752 err = -ENOTSUPP;
753 goto out;
754 }
755
756 if (!ndev->npinfo) {
Amerigo Wang47be03a22012-08-10 01:24:37 +0000757 npinfo = kmalloc(sizeof(*npinfo), gfp);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000758 if (!npinfo) {
759 err = -ENOMEM;
760 goto out;
761 }
762
763 npinfo->rx_flags = 0;
764 INIT_LIST_HEAD(&npinfo->rx_np);
765
766 spin_lock_init(&npinfo->rx_lock);
767 skb_queue_head_init(&npinfo->arp_tx);
768 skb_queue_head_init(&npinfo->txq);
769 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
770
771 atomic_set(&npinfo->refcnt, 1);
772
773 ops = np->dev->netdev_ops;
774 if (ops->ndo_netpoll_setup) {
Amerigo Wang47be03a22012-08-10 01:24:37 +0000775 err = ops->ndo_netpoll_setup(ndev, npinfo, gfp);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000776 if (err)
777 goto free_npinfo;
778 }
779 } else {
780 npinfo = ndev->npinfo;
781 atomic_inc(&npinfo->refcnt);
782 }
783
784 npinfo->netpoll = np;
785
786 if (np->rx_hook) {
787 spin_lock_irqsave(&npinfo->rx_lock, flags);
788 npinfo->rx_flags |= NETPOLL_RX_ENABLED;
789 list_add_tail(&np->rx, &npinfo->rx_np);
790 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
791 }
792
793 /* last thing to do is link it to the net device structure */
Eric Dumazetcf778b02012-01-12 04:41:32 +0000794 rcu_assign_pointer(ndev->npinfo, npinfo);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000795
796 return 0;
797
798free_npinfo:
799 kfree(npinfo);
800out:
801 return err;
802}
803EXPORT_SYMBOL_GPL(__netpoll_setup);
804
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805int netpoll_setup(struct netpoll *np)
806{
807 struct net_device *ndev = NULL;
808 struct in_device *in_dev;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700809 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810
811 if (np->dev_name)
Eric W. Biederman881d9662007-09-17 11:56:21 -0700812 ndev = dev_get_by_name(&init_net, np->dev_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 if (!ndev) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000814 np_err(np, "%s doesn't exist, aborting\n", np->dev_name);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700815 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 }
817
WANG Cong0c1ad042011-06-09 00:28:13 -0700818 if (ndev->master) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000819 np_err(np, "%s is a slave device, aborting\n", np->dev_name);
Dan Carpenter83fe32d2011-06-11 18:55:22 -0700820 err = -EBUSY;
821 goto put;
WANG Cong0c1ad042011-06-09 00:28:13 -0700822 }
823
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824 if (!netif_running(ndev)) {
825 unsigned long atmost, atleast;
826
Joe Perchese6ec269352012-01-29 15:50:43 +0000827 np_info(np, "device %s not up yet, forcing it\n", np->dev_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828
Stephen Hemminger6756ae42006-03-20 22:23:58 -0800829 rtnl_lock();
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700830 err = dev_open(ndev);
831 rtnl_unlock();
832
833 if (err) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000834 np_err(np, "failed to open %s\n", ndev->name);
Herbert Xudbaa1542010-06-10 16:12:46 +0000835 goto put;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837
838 atleast = jiffies + HZ/10;
Anton Vorontsovbff38772009-07-08 11:10:56 -0700839 atmost = jiffies + carrier_timeout * HZ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 while (!netif_carrier_ok(ndev)) {
841 if (time_after(jiffies, atmost)) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000842 np_notice(np, "timeout waiting for carrier\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843 break;
844 }
Anton Vorontsov1b614fb2009-07-08 20:09:44 -0700845 msleep(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 }
847
848 /* If carrier appears to come up instantly, we don't
849 * trust it and pause so that we don't pump all our
850 * queued console messages into the bitbucket.
851 */
852
853 if (time_before(jiffies, atleast)) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000854 np_notice(np, "carrier detect appears untrustworthy, waiting 4 seconds\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855 msleep(4000);
856 }
857 }
858
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 if (!np->local_ip) {
860 rcu_read_lock();
Herbert Xue5ed6392005-10-03 14:35:55 -0700861 in_dev = __in_dev_get_rcu(ndev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862
863 if (!in_dev || !in_dev->ifa_list) {
864 rcu_read_unlock();
Joe Perchese6ec269352012-01-29 15:50:43 +0000865 np_err(np, "no IP address for %s, aborting\n",
866 np->dev_name);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700867 err = -EDESTADDRREQ;
Herbert Xudbaa1542010-06-10 16:12:46 +0000868 goto put;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869 }
870
Harvey Harrisone7557af2009-03-28 15:38:31 +0000871 np->local_ip = in_dev->ifa_list->ifa_local;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872 rcu_read_unlock();
Joe Perchese6ec269352012-01-29 15:50:43 +0000873 np_info(np, "local IP %pI4\n", &np->local_ip);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874 }
875
Herbert Xudbaa1542010-06-10 16:12:46 +0000876 /* fill up the skb queue */
877 refill_skbs();
878
879 rtnl_lock();
Amerigo Wang47be03a22012-08-10 01:24:37 +0000880 err = __netpoll_setup(np, ndev, GFP_KERNEL);
Herbert Xudbaa1542010-06-10 16:12:46 +0000881 rtnl_unlock();
Matt Mackall53fb95d2005-08-11 19:27:43 -0700882
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000883 if (err)
884 goto put;
885
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 return 0;
887
Jiri Slaby21edbb22010-03-16 05:29:54 +0000888put:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 dev_put(ndev);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700890 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000892EXPORT_SYMBOL(netpoll_setup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893
David S. Millerc68b9072006-11-14 20:40:49 -0800894static int __init netpoll_init(void)
895{
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800896 skb_queue_head_init(&skb_pool);
897 return 0;
898}
899core_initcall(netpoll_init);
900
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000901static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head)
902{
903 struct netpoll_info *npinfo =
904 container_of(rcu_head, struct netpoll_info, rcu);
905
906 skb_queue_purge(&npinfo->arp_tx);
907 skb_queue_purge(&npinfo->txq);
908
909 /* we can't call cancel_delayed_work_sync here, as we are in softirq */
910 cancel_delayed_work(&npinfo->tx_work);
911
912 /* clean after last, unfinished work */
913 __skb_queue_purge(&npinfo->txq);
914 /* now cancel it again */
915 cancel_delayed_work(&npinfo->tx_work);
916 kfree(npinfo);
917}
918
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000919void __netpoll_cleanup(struct netpoll *np)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920{
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700921 struct netpoll_info *npinfo;
922 unsigned long flags;
923
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000924 npinfo = np->dev->npinfo;
925 if (!npinfo)
Herbert Xudbaa1542010-06-10 16:12:46 +0000926 return;
Stephen Hemminger93ec2c72006-10-26 15:46:50 -0700927
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000928 if (!list_empty(&npinfo->rx_np)) {
929 spin_lock_irqsave(&npinfo->rx_lock, flags);
930 list_del(&np->rx);
931 if (list_empty(&npinfo->rx_np))
932 npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
933 spin_unlock_irqrestore(&npinfo->rx_lock, flags);
Jeff Moyer115c1d62005-06-22 22:05:31 -0700934 }
Herbert Xudbaa1542010-06-10 16:12:46 +0000935
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000936 if (atomic_dec_and_test(&npinfo->refcnt)) {
937 const struct net_device_ops *ops;
938
939 ops = np->dev->netdev_ops;
940 if (ops->ndo_netpoll_cleanup)
941 ops->ndo_netpoll_cleanup(np->dev);
942
Stephen Hemmingera9b3cd72011-08-01 16:19:00 +0000943 RCU_INIT_POINTER(np->dev->npinfo, NULL);
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000944 call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info);
Herbert Xudbaa1542010-06-10 16:12:46 +0000945 }
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000946}
947EXPORT_SYMBOL_GPL(__netpoll_cleanup);
948
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000949static void rcu_cleanup_netpoll(struct rcu_head *rcu_head)
950{
951 struct netpoll *np = container_of(rcu_head, struct netpoll, rcu);
952
953 __netpoll_cleanup(np);
954 kfree(np);
955}
956
957void __netpoll_free_rcu(struct netpoll *np)
958{
959 call_rcu_bh(&np->rcu, rcu_cleanup_netpoll);
960}
961EXPORT_SYMBOL_GPL(__netpoll_free_rcu);
962
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000963void netpoll_cleanup(struct netpoll *np)
964{
965 if (!np->dev)
966 return;
967
968 rtnl_lock();
969 __netpoll_cleanup(np);
970 rtnl_unlock();
Herbert Xudbaa1542010-06-10 16:12:46 +0000971
972 dev_put(np->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973 np->dev = NULL;
974}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000975EXPORT_SYMBOL(netpoll_cleanup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976
977int netpoll_trap(void)
978{
979 return atomic_read(&trapped);
980}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000981EXPORT_SYMBOL(netpoll_trap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700982
983void netpoll_set_trap(int trap)
984{
985 if (trap)
986 atomic_inc(&trapped);
987 else
988 atomic_dec(&trapped);
989}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990EXPORT_SYMBOL(netpoll_set_trap);