blob: 94acfc89ad976da245bed577511bd7a1c079f6f5 [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>
Andy Shevchenko4cd57732013-06-04 19:46:26 +030015#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/netdevice.h>
17#include <linux/etherdevice.h>
18#include <linux/string.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020019#include <linux/if_arp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/inetdevice.h>
21#include <linux/inet.h>
22#include <linux/interrupt.h>
23#include <linux/netpoll.h>
24#include <linux/sched.h>
25#include <linux/delay.h>
26#include <linux/rcupdate.h>
27#include <linux/workqueue.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090028#include <linux/slab.h>
Paul Gortmakerbc3b2d72011-07-15 11:47:34 -040029#include <linux/export.h>
Amerigo Wang689971b2012-08-10 01:24:49 +000030#include <linux/if_vlan.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <net/tcp.h>
32#include <net/udp.h>
Cong Wangb3d936f2013-01-07 20:52:41 +000033#include <net/addrconf.h>
34#include <net/ndisc.h>
35#include <net/ip6_checksum.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include <asm/unaligned.h>
David S. Miller9cbc1cb2009-06-15 03:02:23 -070037#include <trace/events/napi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39/*
40 * We maintain a small pool of fully-sized skbs, to make sure the
41 * message gets out even in extreme OOM situations.
42 */
43
44#define MAX_UDP_CHUNK 1460
45#define MAX_SKBS 32
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -080047static struct sk_buff_head skb_pool;
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
Lai Jiangshan7f9421c2013-03-15 06:50:52 +000049DEFINE_STATIC_SRCU(netpoll_srcu);
Neil Hormanca99ca12013-02-05 08:05:43 +000050
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -070051#define USEC_PER_POLL 50
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
Joe Perches6f706242012-01-29 15:50:44 +000053#define MAX_SKB_SIZE \
54 (sizeof(struct ethhdr) + \
55 sizeof(struct iphdr) + \
56 sizeof(struct udphdr) + \
57 MAX_UDP_CHUNK)
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
David S. Miller3578b0c2010-08-03 00:24:04 -070059static void zap_completion_queue(void);
Neil Horman2cde6ac2013-02-11 10:25:30 +000060static void netpoll_async_cleanup(struct work_struct *work);
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
Anton Vorontsovbff38772009-07-08 11:10:56 -070062static unsigned int carrier_timeout = 4;
63module_param(carrier_timeout, uint, 0644);
64
Joe Perchese6ec269352012-01-29 15:50:43 +000065#define np_info(np, fmt, ...) \
66 pr_info("%s: " fmt, np->name, ##__VA_ARGS__)
67#define np_err(np, fmt, ...) \
68 pr_err("%s: " fmt, np->name, ##__VA_ARGS__)
69#define np_notice(np, fmt, ...) \
70 pr_notice("%s: " fmt, np->name, ##__VA_ARGS__)
71
Eric W. Biederman944e2942014-03-27 15:37:28 -070072static int netpoll_start_xmit(struct sk_buff *skb, struct net_device *dev,
73 struct netdev_queue *txq)
74{
Eric W. Biederman944e2942014-03-27 15:37:28 -070075 int status = NETDEV_TX_OK;
76 netdev_features_t features;
77
78 features = netif_skb_features(skb);
79
Jiri Pirkodf8a39d2015-01-13 17:13:44 +010080 if (skb_vlan_tag_present(skb) &&
Eric W. Biederman944e2942014-03-27 15:37:28 -070081 !vlan_hw_offload_capable(features, skb->vlan_proto)) {
Jiri Pirko59682502014-11-19 14:04:59 +010082 skb = __vlan_hwaccel_push_inside(skb);
Eric W. Biederman944e2942014-03-27 15:37:28 -070083 if (unlikely(!skb)) {
84 /* This is actually a packet drop, but we
85 * don't want the code that calls this
86 * function to try and operate on a NULL skb.
87 */
88 goto out;
89 }
Eric W. Biederman944e2942014-03-27 15:37:28 -070090 }
91
David S. Millerfa2dbdc2014-08-29 21:55:22 -070092 status = netdev_start_xmit(skb, dev, txq, false);
Eric W. Biederman944e2942014-03-27 15:37:28 -070093
94out:
95 return status;
96}
97
David Howellsc4028952006-11-22 14:57:56 +000098static void queue_process(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -070099{
David Howells4c1ac1b2006-12-05 14:37:56 +0000100 struct netpoll_info *npinfo =
101 container_of(work, struct netpoll_info, tx_work.work);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 struct sk_buff *skb;
Ingo Molnar36405432006-12-12 17:20:42 +0100103 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104
Stephen Hemminger6c43ff12006-10-26 15:46:53 -0700105 while ((skb = skb_dequeue(&npinfo->txq))) {
106 struct net_device *dev = skb->dev;
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700107 struct netdev_queue *txq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108
Stephen Hemminger6c43ff12006-10-26 15:46:53 -0700109 if (!netif_device_present(dev) || !netif_running(dev)) {
Eric W. Biederman080b3c12014-03-27 15:41:04 -0700110 kfree_skb(skb);
Stephen Hemminger6c43ff12006-10-26 15:46:53 -0700111 continue;
112 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113
Daniel Borkmann10c51b56232014-08-27 11:11:27 +0200114 txq = skb_get_tx_queue(dev, skb);
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700115
Ingo Molnar36405432006-12-12 17:20:42 +0100116 local_irq_save(flags);
Eric W. Biederman5efeac42014-03-27 15:42:20 -0700117 HARD_TX_LOCK(dev, txq, smp_processor_id());
Tom Herbert734664982011-11-28 16:32:44 +0000118 if (netif_xmit_frozen_or_stopped(txq) ||
Eric W. Biederman944e2942014-03-27 15:37:28 -0700119 netpoll_start_xmit(skb, dev, txq) != NETDEV_TX_OK) {
Stephen Hemminger6c43ff12006-10-26 15:46:53 -0700120 skb_queue_head(&npinfo->txq, skb);
Eric W. Biederman5efeac42014-03-27 15:42:20 -0700121 HARD_TX_UNLOCK(dev, txq);
Ingo Molnar36405432006-12-12 17:20:42 +0100122 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123
Jarek Poplawski25442ca2007-07-05 17:42:44 -0700124 schedule_delayed_work(&npinfo->tx_work, HZ/10);
Stephen Hemminger6c43ff12006-10-26 15:46:53 -0700125 return;
126 }
Eric W. Biederman5efeac42014-03-27 15:42:20 -0700127 HARD_TX_UNLOCK(dev, txq);
Ingo Molnar36405432006-12-12 17:20:42 +0100128 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 }
130}
131
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132/*
133 * Check whether delayed processing was scheduled for our NIC. If so,
134 * we attempt to grab the poll lock and use ->poll() to pump the card.
135 * If this fails, either we've recursed in ->poll() or it's already
136 * running on another CPU.
137 *
138 * Note: we don't mask interrupts with this lock because we're using
139 * trylock here and interrupts are already disabled in the softirq
140 * case. Further, we test the poll_owner to avoid recursion on UP
141 * systems where the lock doesn't exist.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 */
Alexander Duyck822d54b2015-09-28 09:16:17 -0700143static void poll_one_napi(struct napi_struct *napi)
David S. Miller0a7606c2007-10-29 21:28:47 -0700144{
Neil Horman2d8bff12015-09-23 14:57:58 -0400145 int work = 0;
David S. Miller0a7606c2007-10-29 21:28:47 -0700146
147 /* net_rx_action's ->poll() invocations and our's are
148 * synchronized by this test which is only made while
149 * holding the napi->poll_lock.
150 */
151 if (!test_bit(NAPI_STATE_SCHED, &napi->state))
Alexander Duyck822d54b2015-09-28 09:16:17 -0700152 return;
David S. Miller0a7606c2007-10-29 21:28:47 -0700153
Neil Horman2d8bff12015-09-23 14:57:58 -0400154 /* If we set this bit but see that it has already been set,
155 * that indicates that napi has been disabled and we need
156 * to abort this operation
157 */
158 if (test_and_set_bit(NAPI_STATE_NPSVC, &napi->state))
Alexander Duyck822d54b2015-09-28 09:16:17 -0700159 return;
David S. Miller0a7606c2007-10-29 21:28:47 -0700160
Alexander Duyck822d54b2015-09-28 09:16:17 -0700161 /* We explicilty pass the polling call a budget of 0 to
162 * indicate that we are clearing the Tx path only.
163 */
164 work = napi->poll(napi, 0);
165 WARN_ONCE(work, "%pF exceeded budget in poll\n", napi->poll);
David S. Miller7d18f112009-05-21 23:30:09 -0700166 trace_napi_poll(napi);
David S. Miller0a7606c2007-10-29 21:28:47 -0700167
Neil Horman7b363e42008-12-09 23:22:26 -0800168 clear_bit(NAPI_STATE_NPSVC, &napi->state);
David S. Miller0a7606c2007-10-29 21:28:47 -0700169}
170
Alexander Duyck822d54b2015-09-28 09:16:17 -0700171static void poll_napi(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172{
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700173 struct napi_struct *napi;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174
Neil Hormanf13d4932010-10-19 07:04:26 +0000175 list_for_each_entry(napi, &dev->napi_list, dev_list) {
David S. Miller0a7606c2007-10-29 21:28:47 -0700176 if (napi->poll_owner != smp_processor_id() &&
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700177 spin_trylock(&napi->poll_lock)) {
Alexander Duyck822d54b2015-09-28 09:16:17 -0700178 poll_one_napi(napi);
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700179 spin_unlock(&napi->poll_lock);
180 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 }
182}
183
Joe Perches234b9212011-06-30 15:08:57 +0000184static void netpoll_poll_dev(struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185{
Pavel Emelyanov5e392732009-05-11 00:36:35 +0000186 const struct net_device_ops *ops;
Amerigo Wang28996562012-08-10 01:24:42 +0000187 struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo);
Stephen Hemminger51069302007-11-19 19:18:11 -0800188
Neil Hormanca99ca12013-02-05 08:05:43 +0000189 /* Don't do any rx activity if the dev_lock mutex is held
190 * the dev_open/close paths use this to block netpoll activity
191 * while changing device state
192 */
Dan Carpentera3dbbc22013-05-06 02:15:13 +0000193 if (down_trylock(&ni->dev_lock))
Neil Hormanca99ca12013-02-05 08:05:43 +0000194 return;
195
Neil Horman959d5fd2013-02-13 11:32:42 -0500196 if (!netif_running(dev)) {
Neil Hormanbd7c4b62013-04-30 05:35:05 +0000197 up(&ni->dev_lock);
Pavel Emelyanov5e392732009-05-11 00:36:35 +0000198 return;
Neil Horman959d5fd2013-02-13 11:32:42 -0500199 }
Pavel Emelyanov5e392732009-05-11 00:36:35 +0000200
201 ops = dev->netdev_ops;
Neil Horman959d5fd2013-02-13 11:32:42 -0500202 if (!ops->ndo_poll_controller) {
Neil Hormanbd7c4b62013-04-30 05:35:05 +0000203 up(&ni->dev_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 return;
Neil Horman959d5fd2013-02-13 11:32:42 -0500205 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206
207 /* Process pending work on NIC */
Stephen Hemmingerd3147742008-11-19 21:32:24 -0800208 ops->ndo_poll_controller(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
Alexander Duyck822d54b2015-09-28 09:16:17 -0700210 poll_napi(dev);
Stephen Hemminger51069302007-11-19 19:18:11 -0800211
Neil Hormanbd7c4b62013-04-30 05:35:05 +0000212 up(&ni->dev_lock);
Neil Hormanca99ca12013-02-05 08:05:43 +0000213
David S. Miller3578b0c2010-08-03 00:24:04 -0700214 zap_completion_queue();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215}
216
Eric W. Biederman66b55522014-03-27 15:39:03 -0700217void netpoll_poll_disable(struct net_device *dev)
Neil Hormanca99ca12013-02-05 08:05:43 +0000218{
219 struct netpoll_info *ni;
220 int idx;
221 might_sleep();
222 idx = srcu_read_lock(&netpoll_srcu);
223 ni = srcu_dereference(dev->npinfo, &netpoll_srcu);
224 if (ni)
Neil Hormanbd7c4b62013-04-30 05:35:05 +0000225 down(&ni->dev_lock);
Neil Hormanca99ca12013-02-05 08:05:43 +0000226 srcu_read_unlock(&netpoll_srcu, idx);
Neil Hormanca99ca12013-02-05 08:05:43 +0000227}
Eric W. Biederman66b55522014-03-27 15:39:03 -0700228EXPORT_SYMBOL(netpoll_poll_disable);
Neil Hormanca99ca12013-02-05 08:05:43 +0000229
Eric W. Biederman66b55522014-03-27 15:39:03 -0700230void netpoll_poll_enable(struct net_device *dev)
Neil Hormanca99ca12013-02-05 08:05:43 +0000231{
232 struct netpoll_info *ni;
233 rcu_read_lock();
234 ni = rcu_dereference(dev->npinfo);
235 if (ni)
Neil Hormanbd7c4b62013-04-30 05:35:05 +0000236 up(&ni->dev_lock);
Neil Hormanca99ca12013-02-05 08:05:43 +0000237 rcu_read_unlock();
238}
Eric W. Biederman66b55522014-03-27 15:39:03 -0700239EXPORT_SYMBOL(netpoll_poll_enable);
Neil Hormanca99ca12013-02-05 08:05:43 +0000240
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241static void refill_skbs(void)
242{
243 struct sk_buff *skb;
244 unsigned long flags;
245
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800246 spin_lock_irqsave(&skb_pool.lock, flags);
247 while (skb_pool.qlen < MAX_SKBS) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC);
249 if (!skb)
250 break;
251
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800252 __skb_queue_tail(&skb_pool, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 }
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800254 spin_unlock_irqrestore(&skb_pool.lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255}
256
David S. Miller3578b0c2010-08-03 00:24:04 -0700257static void zap_completion_queue(void)
258{
259 unsigned long flags;
260 struct softnet_data *sd = &get_cpu_var(softnet_data);
261
262 if (sd->completion_queue) {
263 struct sk_buff *clist;
264
265 local_irq_save(flags);
266 clist = sd->completion_queue;
267 sd->completion_queue = NULL;
268 local_irq_restore(flags);
269
270 while (clist != NULL) {
271 struct sk_buff *skb = clist;
272 clist = clist->next;
Eric W. Biedermanb1586f02014-04-01 12:21:02 -0700273 if (!skb_irq_freeable(skb)) {
David S. Miller3578b0c2010-08-03 00:24:04 -0700274 atomic_inc(&skb->users);
275 dev_kfree_skb_any(skb); /* put this one back */
276 } else {
277 __kfree_skb(skb);
278 }
279 }
280 }
281
282 put_cpu_var(softnet_data);
283}
284
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800285static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286{
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800287 int count = 0;
288 struct sk_buff *skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289
David S. Miller3578b0c2010-08-03 00:24:04 -0700290 zap_completion_queue();
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800291 refill_skbs();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292repeat:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293
294 skb = alloc_skb(len, GFP_ATOMIC);
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800295 if (!skb)
296 skb = skb_dequeue(&skb_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297
298 if (!skb) {
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800299 if (++count < 10) {
Joe Perches2a49e002011-06-30 15:08:58 +0000300 netpoll_poll_dev(np->dev);
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800301 goto repeat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 }
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800303 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 }
305
306 atomic_set(&skb->users, 1);
307 skb_reserve(skb, reserve);
308 return skb;
309}
310
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700311static int netpoll_owner_active(struct net_device *dev)
312{
313 struct napi_struct *napi;
314
315 list_for_each_entry(napi, &dev->napi_list, dev_list) {
316 if (napi->poll_owner == smp_processor_id())
317 return 1;
318 }
319 return 0;
320}
321
Amerigo Wang28996562012-08-10 01:24:42 +0000322/* call with IRQ disabled */
Neil Hormanc2355e12010-10-13 16:01:49 +0000323void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
324 struct net_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325{
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700326 int status = NETDEV_TX_BUSY;
327 unsigned long tries;
Herbert Xude85d992010-06-10 16:12:44 +0000328 /* It is up to the caller to keep npinfo alive. */
Amerigo Wang28996562012-08-10 01:24:42 +0000329 struct netpoll_info *npinfo;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330
Amerigo Wang28996562012-08-10 01:24:42 +0000331 WARN_ON_ONCE(!irqs_disabled());
332
333 npinfo = rcu_dereference_bh(np->dev->npinfo);
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900334 if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
Eric W. Biederman080b3c12014-03-27 15:41:04 -0700335 dev_kfree_skb_irq(skb);
YOSHIFUJI Hideaki4ec93ed2007-02-09 23:24:36 +0900336 return;
337 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700339 /* don't get messages out of order, and no recursion */
Stephen Hemmingerbea33482007-10-03 16:41:36 -0700340 if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) {
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700341 struct netdev_queue *txq;
Andrew Mortona49f99f2006-12-11 17:24:46 -0800342
Jason Wangf663dd92014-01-10 16:18:26 +0800343 txq = netdev_pick_tx(dev, skb, NULL);
David S. Millerfd2ea0a2008-07-17 01:56:23 -0700344
Stephen Hemminger0db3dc72007-06-27 00:39:42 -0700345 /* try until next clock tick */
346 for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
347 tries > 0; --tries) {
Eric W. Biederman5efeac42014-03-27 15:42:20 -0700348 if (HARD_TX_TRYLOCK(dev, txq)) {
Eric W. Biederman944e2942014-03-27 15:37:28 -0700349 if (!netif_xmit_stopped(txq))
350 status = netpoll_start_xmit(skb, dev, txq);
Amerigo Wang689971b2012-08-10 01:24:49 +0000351
Eric W. Biederman5efeac42014-03-27 15:42:20 -0700352 HARD_TX_UNLOCK(dev, txq);
Matt Mackallf0d34592005-08-11 19:25:11 -0700353
Andrew Mortone37b8d92006-12-09 14:01:49 -0800354 if (status == NETDEV_TX_OK)
355 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
Andrew Mortone37b8d92006-12-09 14:01:49 -0800357 }
Stephen Hemminger0db3dc72007-06-27 00:39:42 -0700358
359 /* tickle device maybe there is some cleanup */
Joe Perches2a49e002011-06-30 15:08:58 +0000360 netpoll_poll_dev(np->dev);
Stephen Hemminger0db3dc72007-06-27 00:39:42 -0700361
362 udelay(USEC_PER_POLL);
Matt Mackall0db1d6f2005-08-11 19:25:54 -0700363 }
Dongdong Deng79b1bee2009-08-21 03:33:36 +0000364
365 WARN_ONCE(!irqs_disabled(),
Amerigo Wang28996562012-08-10 01:24:42 +0000366 "netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pF)\n",
Eric W. Biederman944e2942014-03-27 15:37:28 -0700367 dev->name, dev->netdev_ops->ndo_start_xmit);
Dongdong Deng79b1bee2009-08-21 03:33:36 +0000368
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370
Stephen Hemminger2bdfe0b2006-10-26 15:46:54 -0700371 if (status != NETDEV_TX_OK) {
Stephen Hemminger5de4a472006-10-26 15:46:55 -0700372 skb_queue_tail(&npinfo->txq, skb);
David Howells4c1ac1b2006-12-05 14:37:56 +0000373 schedule_delayed_work(&npinfo->tx_work,0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375}
Neil Hormanc2355e12010-10-13 16:01:49 +0000376EXPORT_SYMBOL(netpoll_send_skb_on_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
378void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
379{
Eric Dumazet954fba02012-06-12 19:30:21 +0000380 int total_len, ip_len, udp_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 struct sk_buff *skb;
382 struct udphdr *udph;
383 struct iphdr *iph;
384 struct ethhdr *eth;
Eric Dumazetee130402012-08-24 01:47:26 +0000385 static atomic_t ip_ident;
Cong Wangb3d936f2013-01-07 20:52:41 +0000386 struct ipv6hdr *ip6h;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
Nikolay Aleksandrovc9fd56b2015-08-28 15:44:25 -0700388 WARN_ON_ONCE(!irqs_disabled());
389
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390 udp_len = len + sizeof(*udph);
Cong Wangb3d936f2013-01-07 20:52:41 +0000391 if (np->ipv6)
392 ip_len = udp_len + sizeof(*ip6h);
393 else
Cong Wangb7394d22013-01-07 20:52:39 +0000394 ip_len = udp_len + sizeof(*iph);
395
Eric Dumazet954fba02012-06-12 19:30:21 +0000396 total_len = ip_len + LL_RESERVED_SPACE(np->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Eric Dumazet954fba02012-06-12 19:30:21 +0000398 skb = find_skb(np, total_len + np->dev->needed_tailroom,
399 total_len - len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 if (!skb)
401 return;
402
Arnaldo Carvalho de Melo27d7ff42007-03-31 11:55:19 -0300403 skb_copy_to_linear_data(skb, msg, len);
Eric Dumazet954fba02012-06-12 19:30:21 +0000404 skb_put(skb, len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405
Arnaldo Carvalho de Melo4bedb452007-03-13 14:28:48 -0300406 skb_push(skb, sizeof(*udph));
407 skb_reset_transport_header(skb);
408 udph = udp_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 udph->source = htons(np->local_port);
410 udph->dest = htons(np->remote_port);
411 udph->len = htons(udp_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412
Cong Wangb3d936f2013-01-07 20:52:41 +0000413 if (np->ipv6) {
414 udph->check = 0;
415 udph->check = csum_ipv6_magic(&np->local_ip.in6,
416 &np->remote_ip.in6,
417 udp_len, IPPROTO_UDP,
418 csum_partial(udph, udp_len, 0));
419 if (udph->check == 0)
420 udph->check = CSUM_MANGLED_0;
421
422 skb_push(skb, sizeof(*ip6h));
423 skb_reset_network_header(skb);
424 ip6h = ipv6_hdr(skb);
425
426 /* ip6h->version = 6; ip6h->priority = 0; */
427 put_unaligned(0x60, (unsigned char *)ip6h);
428 ip6h->flow_lbl[0] = 0;
429 ip6h->flow_lbl[1] = 0;
430 ip6h->flow_lbl[2] = 0;
431
432 ip6h->payload_len = htons(sizeof(struct udphdr) + len);
433 ip6h->nexthdr = IPPROTO_UDP;
434 ip6h->hop_limit = 32;
435 ip6h->saddr = np->local_ip.in6;
436 ip6h->daddr = np->remote_ip.in6;
437
438 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
439 skb_reset_mac_header(skb);
440 skb->protocol = eth->h_proto = htons(ETH_P_IPV6);
441 } else {
Cong Wangb7394d22013-01-07 20:52:39 +0000442 udph->check = 0;
443 udph->check = csum_tcpudp_magic(np->local_ip.ip,
444 np->remote_ip.ip,
445 udp_len, IPPROTO_UDP,
446 csum_partial(udph, udp_len, 0));
447 if (udph->check == 0)
448 udph->check = CSUM_MANGLED_0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449
Cong Wangb7394d22013-01-07 20:52:39 +0000450 skb_push(skb, sizeof(*iph));
451 skb_reset_network_header(skb);
452 iph = ip_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453
Cong Wangb7394d22013-01-07 20:52:39 +0000454 /* iph->version = 4; iph->ihl = 5; */
455 put_unaligned(0x45, (unsigned char *)iph);
456 iph->tos = 0;
457 put_unaligned(htons(ip_len), &(iph->tot_len));
458 iph->id = htons(atomic_inc_return(&ip_ident));
459 iph->frag_off = 0;
460 iph->ttl = 64;
461 iph->protocol = IPPROTO_UDP;
462 iph->check = 0;
463 put_unaligned(np->local_ip.ip, &(iph->saddr));
464 put_unaligned(np->remote_ip.ip, &(iph->daddr));
465 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
466
467 eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
468 skb_reset_mac_header(skb);
469 skb->protocol = eth->h_proto = htons(ETH_P_IP);
470 }
471
Joe Perchesc62326a2014-01-20 09:52:18 -0800472 ether_addr_copy(eth->h_source, np->dev->dev_addr);
473 ether_addr_copy(eth->h_dest, np->remote_mac);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474
475 skb->dev = np->dev;
476
477 netpoll_send_skb(np, skb);
478}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000479EXPORT_SYMBOL(netpoll_send_udp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700481void netpoll_print_options(struct netpoll *np)
482{
Joe Perchese6ec269352012-01-29 15:50:43 +0000483 np_info(np, "local port %d\n", np->local_port);
Cong Wangb3d936f2013-01-07 20:52:41 +0000484 if (np->ipv6)
485 np_info(np, "local IPv6 address %pI6c\n", &np->local_ip.in6);
486 else
Cong Wangb7394d22013-01-07 20:52:39 +0000487 np_info(np, "local IPv4 address %pI4\n", &np->local_ip.ip);
Joe Perchese6ec269352012-01-29 15:50:43 +0000488 np_info(np, "interface '%s'\n", np->dev_name);
489 np_info(np, "remote port %d\n", np->remote_port);
Cong Wangb3d936f2013-01-07 20:52:41 +0000490 if (np->ipv6)
491 np_info(np, "remote IPv6 address %pI6c\n", &np->remote_ip.in6);
492 else
Cong Wangb7394d22013-01-07 20:52:39 +0000493 np_info(np, "remote IPv4 address %pI4\n", &np->remote_ip.ip);
Joe Perchese6ec269352012-01-29 15:50:43 +0000494 np_info(np, "remote ethernet address %pM\n", np->remote_mac);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700495}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000496EXPORT_SYMBOL(netpoll_print_options);
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700497
Cong Wangb7394d22013-01-07 20:52:39 +0000498static int netpoll_parse_ip_addr(const char *str, union inet_addr *addr)
499{
500 const char *end;
501
502 if (!strchr(str, ':') &&
503 in4_pton(str, -1, (void *)addr, -1, &end) > 0) {
504 if (!*end)
505 return 0;
506 }
507 if (in6_pton(str, -1, addr->in6.s6_addr, -1, &end) > 0) {
508#if IS_ENABLED(CONFIG_IPV6)
509 if (!*end)
510 return 1;
511#else
512 return -1;
513#endif
514 }
515 return -1;
516}
517
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518int netpoll_parse_options(struct netpoll *np, char *opt)
519{
520 char *cur=opt, *delim;
Cong Wangb7394d22013-01-07 20:52:39 +0000521 int ipv6;
Sabrina Dubroca00fe11b2014-02-06 18:34:12 +0100522 bool ipversion_set = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523
David S. Millerc68b9072006-11-14 20:40:49 -0800524 if (*cur != '@') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525 if ((delim = strchr(cur, '@')) == NULL)
526 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800527 *delim = 0;
Abhijit Pawar4b5511e2012-12-09 23:12:28 +0000528 if (kstrtou16(cur, 10, &np->local_port))
529 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800530 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 }
532 cur++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533
David S. Millerc68b9072006-11-14 20:40:49 -0800534 if (*cur != '/') {
Sabrina Dubroca00fe11b2014-02-06 18:34:12 +0100535 ipversion_set = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 if ((delim = strchr(cur, '/')) == NULL)
537 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800538 *delim = 0;
Cong Wangb7394d22013-01-07 20:52:39 +0000539 ipv6 = netpoll_parse_ip_addr(cur, &np->local_ip);
540 if (ipv6 < 0)
541 goto parse_failed;
542 else
543 np->ipv6 = (bool)ipv6;
David S. Millerc68b9072006-11-14 20:40:49 -0800544 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 }
546 cur++;
547
David S. Millerc68b9072006-11-14 20:40:49 -0800548 if (*cur != ',') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 /* parse out dev name */
550 if ((delim = strchr(cur, ',')) == NULL)
551 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800552 *delim = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 strlcpy(np->dev_name, cur, sizeof(np->dev_name));
David S. Millerc68b9072006-11-14 20:40:49 -0800554 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 }
556 cur++;
557
David S. Millerc68b9072006-11-14 20:40:49 -0800558 if (*cur != '@') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 /* dst port */
560 if ((delim = strchr(cur, '@')) == NULL)
561 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800562 *delim = 0;
Amerigo Wang5fc05f82010-03-21 22:59:58 +0000563 if (*cur == ' ' || *cur == '\t')
Joe Perchese6ec269352012-01-29 15:50:43 +0000564 np_info(np, "warning: whitespace is not allowed\n");
Abhijit Pawar4b5511e2012-12-09 23:12:28 +0000565 if (kstrtou16(cur, 10, &np->remote_port))
566 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800567 cur = delim;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 }
569 cur++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570
571 /* dst ip */
572 if ((delim = strchr(cur, '/')) == NULL)
573 goto parse_failed;
David S. Millerc68b9072006-11-14 20:40:49 -0800574 *delim = 0;
Cong Wangb7394d22013-01-07 20:52:39 +0000575 ipv6 = netpoll_parse_ip_addr(cur, &np->remote_ip);
576 if (ipv6 < 0)
577 goto parse_failed;
Sabrina Dubroca00fe11b2014-02-06 18:34:12 +0100578 else if (ipversion_set && np->ipv6 != (bool)ipv6)
Cong Wangb7394d22013-01-07 20:52:39 +0000579 goto parse_failed;
580 else
581 np->ipv6 = (bool)ipv6;
David S. Millerc68b9072006-11-14 20:40:49 -0800582 cur = delim + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583
David S. Millerc68b9072006-11-14 20:40:49 -0800584 if (*cur != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 /* MAC address */
Alexey Dobriyan4940fc82011-05-07 23:00:07 +0000586 if (!mac_pton(cur, np->remote_mac))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 goto parse_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 }
589
Satyam Sharma0bcc1812007-08-10 15:35:05 -0700590 netpoll_print_options(np);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591
592 return 0;
593
594 parse_failed:
Joe Perchese6ec269352012-01-29 15:50:43 +0000595 np_info(np, "couldn't parse config at '%s'!\n", cur);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 return -1;
597}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000598EXPORT_SYMBOL(netpoll_parse_options);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
Eric W. Biedermana8779ec2014-03-27 15:36:38 -0700600int __netpoll_setup(struct netpoll *np, struct net_device *ndev)
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000601{
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000602 struct netpoll_info *npinfo;
603 const struct net_device_ops *ops;
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000604 int err;
605
Jiri Pirko30fdd8a02012-07-17 05:22:35 +0000606 np->dev = ndev;
607 strlcpy(np->dev_name, ndev->name, IFNAMSIZ);
Neil Horman2cde6ac2013-02-11 10:25:30 +0000608 INIT_WORK(&np->cleanup_work, netpoll_async_cleanup);
Jiri Pirko30fdd8a02012-07-17 05:22:35 +0000609
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000610 if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
611 !ndev->netdev_ops->ndo_poll_controller) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000612 np_err(np, "%s doesn't support polling, aborting\n",
613 np->dev_name);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000614 err = -ENOTSUPP;
615 goto out;
616 }
617
618 if (!ndev->npinfo) {
Eric W. Biedermana8779ec2014-03-27 15:36:38 -0700619 npinfo = kmalloc(sizeof(*npinfo), GFP_KERNEL);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000620 if (!npinfo) {
621 err = -ENOMEM;
622 goto out;
623 }
624
Neil Hormanbd7c4b62013-04-30 05:35:05 +0000625 sema_init(&npinfo->dev_lock, 1);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000626 skb_queue_head_init(&npinfo->txq);
627 INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
628
629 atomic_set(&npinfo->refcnt, 1);
630
631 ops = np->dev->netdev_ops;
632 if (ops->ndo_netpoll_setup) {
Eric W. Biedermana8779ec2014-03-27 15:36:38 -0700633 err = ops->ndo_netpoll_setup(ndev, npinfo);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000634 if (err)
635 goto free_npinfo;
636 }
637 } else {
Neil Horman0790bbb2013-02-11 10:25:31 +0000638 npinfo = rtnl_dereference(ndev->npinfo);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000639 atomic_inc(&npinfo->refcnt);
640 }
641
642 npinfo->netpoll = np;
643
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000644 /* last thing to do is link it to the net device structure */
Eric Dumazetcf778b02012-01-12 04:41:32 +0000645 rcu_assign_pointer(ndev->npinfo, npinfo);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000646
647 return 0;
648
649free_npinfo:
650 kfree(npinfo);
651out:
652 return err;
653}
654EXPORT_SYMBOL_GPL(__netpoll_setup);
655
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656int netpoll_setup(struct netpoll *np)
657{
658 struct net_device *ndev = NULL;
659 struct in_device *in_dev;
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700660 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661
Cong Wangf92d3182013-01-14 23:34:06 +0000662 rtnl_lock();
Cong Wang556e6252013-01-27 15:55:21 +0000663 if (np->dev_name) {
664 struct net *net = current->nsproxy->net_ns;
665 ndev = __dev_get_by_name(net, np->dev_name);
666 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 if (!ndev) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000668 np_err(np, "%s doesn't exist, aborting\n", np->dev_name);
Cong Wangf92d3182013-01-14 23:34:06 +0000669 err = -ENODEV;
670 goto unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 }
Cong Wang5bd30d32013-01-17 12:21:08 +0800672 dev_hold(ndev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673
Jiri Pirko49bd8fb02013-01-03 22:48:55 +0000674 if (netdev_master_upper_dev_get(ndev)) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000675 np_err(np, "%s is a slave device, aborting\n", np->dev_name);
Dan Carpenter83fe32d2011-06-11 18:55:22 -0700676 err = -EBUSY;
677 goto put;
WANG Cong0c1ad042011-06-09 00:28:13 -0700678 }
679
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 if (!netif_running(ndev)) {
681 unsigned long atmost, atleast;
682
Joe Perchese6ec269352012-01-29 15:50:43 +0000683 np_info(np, "device %s not up yet, forcing it\n", np->dev_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700685 err = dev_open(ndev);
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700686
687 if (err) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000688 np_err(np, "failed to open %s\n", ndev->name);
Herbert Xudbaa1542010-06-10 16:12:46 +0000689 goto put;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691
Cong Wangf92d3182013-01-14 23:34:06 +0000692 rtnl_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693 atleast = jiffies + HZ/10;
Anton Vorontsovbff38772009-07-08 11:10:56 -0700694 atmost = jiffies + carrier_timeout * HZ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695 while (!netif_carrier_ok(ndev)) {
696 if (time_after(jiffies, atmost)) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000697 np_notice(np, "timeout waiting for carrier\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 break;
699 }
Anton Vorontsov1b614fb2009-07-08 20:09:44 -0700700 msleep(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 }
702
703 /* If carrier appears to come up instantly, we don't
704 * trust it and pause so that we don't pump all our
705 * queued console messages into the bitbucket.
706 */
707
708 if (time_before(jiffies, atleast)) {
Joe Perchese6ec269352012-01-29 15:50:43 +0000709 np_notice(np, "carrier detect appears untrustworthy, waiting 4 seconds\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710 msleep(4000);
711 }
Cong Wangf92d3182013-01-14 23:34:06 +0000712 rtnl_lock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 }
714
Cong Wangb7394d22013-01-07 20:52:39 +0000715 if (!np->local_ip.ip) {
716 if (!np->ipv6) {
Cong Wangf92d3182013-01-14 23:34:06 +0000717 in_dev = __in_dev_get_rtnl(ndev);
Cong Wangb7394d22013-01-07 20:52:39 +0000718
719 if (!in_dev || !in_dev->ifa_list) {
Cong Wangb7394d22013-01-07 20:52:39 +0000720 np_err(np, "no IP address for %s, aborting\n",
721 np->dev_name);
722 err = -EDESTADDRREQ;
723 goto put;
724 }
725
726 np->local_ip.ip = in_dev->ifa_list->ifa_local;
Cong Wangb7394d22013-01-07 20:52:39 +0000727 np_info(np, "local IP %pI4\n", &np->local_ip.ip);
Cong Wangb3d936f2013-01-07 20:52:41 +0000728 } else {
729#if IS_ENABLED(CONFIG_IPV6)
730 struct inet6_dev *idev;
731
732 err = -EDESTADDRREQ;
Cong Wangb3d936f2013-01-07 20:52:41 +0000733 idev = __in6_dev_get(ndev);
734 if (idev) {
735 struct inet6_ifaddr *ifp;
736
737 read_lock_bh(&idev->lock);
738 list_for_each_entry(ifp, &idev->addr_list, if_list) {
739 if (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)
740 continue;
741 np->local_ip.in6 = ifp->addr;
742 err = 0;
743 break;
744 }
745 read_unlock_bh(&idev->lock);
746 }
Cong Wangb3d936f2013-01-07 20:52:41 +0000747 if (err) {
748 np_err(np, "no IPv6 address for %s, aborting\n",
749 np->dev_name);
750 goto put;
751 } else
752 np_info(np, "local IPv6 %pI6c\n", &np->local_ip.in6);
753#else
754 np_err(np, "IPv6 is not supported %s, aborting\n",
755 np->dev_name);
Cong Wange39363a2013-01-22 17:39:11 +0000756 err = -EINVAL;
Cong Wangb3d936f2013-01-07 20:52:41 +0000757 goto put;
758#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760 }
761
Herbert Xudbaa1542010-06-10 16:12:46 +0000762 /* fill up the skb queue */
763 refill_skbs();
764
Eric W. Biedermana8779ec2014-03-27 15:36:38 -0700765 err = __netpoll_setup(np, ndev);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000766 if (err)
767 goto put;
768
Cong Wangf92d3182013-01-14 23:34:06 +0000769 rtnl_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 return 0;
771
Jiri Slaby21edbb22010-03-16 05:29:54 +0000772put:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773 dev_put(ndev);
Cong Wangf92d3182013-01-14 23:34:06 +0000774unlock:
775 rtnl_unlock();
Stephen Hemmingerb41848b2006-10-26 15:46:52 -0700776 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000778EXPORT_SYMBOL(netpoll_setup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779
David S. Millerc68b9072006-11-14 20:40:49 -0800780static int __init netpoll_init(void)
781{
Stephen Hemmingera1bcfac2006-11-14 10:43:58 -0800782 skb_queue_head_init(&skb_pool);
783 return 0;
784}
785core_initcall(netpoll_init);
786
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000787static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head)
788{
789 struct netpoll_info *npinfo =
790 container_of(rcu_head, struct netpoll_info, rcu);
791
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000792 skb_queue_purge(&npinfo->txq);
793
794 /* we can't call cancel_delayed_work_sync here, as we are in softirq */
795 cancel_delayed_work(&npinfo->tx_work);
796
797 /* clean after last, unfinished work */
798 __skb_queue_purge(&npinfo->txq);
799 /* now cancel it again */
800 cancel_delayed_work(&npinfo->tx_work);
801 kfree(npinfo);
802}
803
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000804void __netpoll_cleanup(struct netpoll *np)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805{
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700806 struct netpoll_info *npinfo;
Jeff Moyerfbeec2e2005-06-22 22:05:59 -0700807
Neil Horman0790bbb2013-02-11 10:25:31 +0000808 /* rtnl_dereference would be preferable here but
809 * rcu_cleanup_netpoll path can put us in here safely without
810 * holding the rtnl, so plain rcu_dereference it is
811 */
812 npinfo = rtnl_dereference(np->dev->npinfo);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000813 if (!npinfo)
Herbert Xudbaa1542010-06-10 16:12:46 +0000814 return;
Stephen Hemminger93ec2c72006-10-26 15:46:50 -0700815
Neil Hormanca99ca12013-02-05 08:05:43 +0000816 synchronize_srcu(&netpoll_srcu);
817
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000818 if (atomic_dec_and_test(&npinfo->refcnt)) {
819 const struct net_device_ops *ops;
820
821 ops = np->dev->netdev_ops;
822 if (ops->ndo_netpoll_cleanup)
823 ops->ndo_netpoll_cleanup(np->dev);
824
Monam Agarwalfcb144b2014-03-24 00:42:46 +0530825 RCU_INIT_POINTER(np->dev->npinfo, NULL);
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000826 call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info);
david decotignyefa95b02014-07-08 15:14:41 -0700827 } else
828 RCU_INIT_POINTER(np->dev->npinfo, NULL);
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000829}
830EXPORT_SYMBOL_GPL(__netpoll_cleanup);
831
Neil Horman2cde6ac2013-02-11 10:25:30 +0000832static void netpoll_async_cleanup(struct work_struct *work)
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000833{
Neil Horman2cde6ac2013-02-11 10:25:30 +0000834 struct netpoll *np = container_of(work, struct netpoll, cleanup_work);
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000835
Neil Horman2cde6ac2013-02-11 10:25:30 +0000836 rtnl_lock();
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000837 __netpoll_cleanup(np);
Neil Horman2cde6ac2013-02-11 10:25:30 +0000838 rtnl_unlock();
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000839 kfree(np);
840}
841
Neil Horman2cde6ac2013-02-11 10:25:30 +0000842void __netpoll_free_async(struct netpoll *np)
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000843{
Neil Horman2cde6ac2013-02-11 10:25:30 +0000844 schedule_work(&np->cleanup_work);
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000845}
Neil Horman2cde6ac2013-02-11 10:25:30 +0000846EXPORT_SYMBOL_GPL(__netpoll_free_async);
Amerigo Wang38e6bc12012-08-10 01:24:38 +0000847
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000848void netpoll_cleanup(struct netpoll *np)
849{
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000850 rtnl_lock();
Nikolay Aleksandrovd0fe8c882013-09-19 15:02:35 +0200851 if (!np->dev)
852 goto out;
Herbert Xu8fdd95e2010-06-10 16:12:48 +0000853 __netpoll_cleanup(np);
Herbert Xudbaa1542010-06-10 16:12:46 +0000854 dev_put(np->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855 np->dev = NULL;
Nikolay Aleksandrovd0fe8c882013-09-19 15:02:35 +0200856out:
857 rtnl_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858}
Eric Dumazet9e34a5b2010-07-09 21:22:04 +0000859EXPORT_SYMBOL(netpoll_cleanup);