![Simon Horman](/assets/img/avatar_default.png)
This corrects an regression introduced by "net: Use 16bits for *_headers fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In that case skb->tail will be a pointer however skb->network_header is now an offset. This patch corrects the problem by adding a wrapper to return skb tail as an offset regardless of the value of NET_SKBUFF_DATA_USES_OFFSET. It seems that skb->tail that this offset may be more than 64k and some care has been taken to treat such cases as an error. Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
1324 lines
31 KiB
C
1324 lines
31 KiB
C
/*
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* Common framework for low-level network console, dump, and debugger code
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*
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* Sep 8 2003 Matt Mackall <mpm@selenic.com>
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*
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* based on the netconsole code from:
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*
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* Copyright (C) 2001 Ingo Molnar <mingo@redhat.com>
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* Copyright (C) 2002 Red Hat, Inc.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/moduleparam.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/string.h>
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#include <linux/if_arp.h>
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#include <linux/inetdevice.h>
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#include <linux/inet.h>
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#include <linux/interrupt.h>
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#include <linux/netpoll.h>
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#include <linux/sched.h>
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#include <linux/delay.h>
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#include <linux/rcupdate.h>
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#include <linux/workqueue.h>
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#include <linux/slab.h>
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#include <linux/export.h>
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#include <linux/if_vlan.h>
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#include <net/tcp.h>
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#include <net/udp.h>
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#include <net/addrconf.h>
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#include <net/ndisc.h>
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#include <net/ip6_checksum.h>
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#include <asm/unaligned.h>
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#include <trace/events/napi.h>
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/*
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* We maintain a small pool of fully-sized skbs, to make sure the
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* message gets out even in extreme OOM situations.
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*/
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#define MAX_UDP_CHUNK 1460
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#define MAX_SKBS 32
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static struct sk_buff_head skb_pool;
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static atomic_t trapped;
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DEFINE_STATIC_SRCU(netpoll_srcu);
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#define USEC_PER_POLL 50
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#define NETPOLL_RX_ENABLED 1
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#define NETPOLL_RX_DROP 2
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#define MAX_SKB_SIZE \
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(sizeof(struct ethhdr) + \
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sizeof(struct iphdr) + \
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sizeof(struct udphdr) + \
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MAX_UDP_CHUNK)
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static void zap_completion_queue(void);
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static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo);
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static void netpoll_async_cleanup(struct work_struct *work);
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static unsigned int carrier_timeout = 4;
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module_param(carrier_timeout, uint, 0644);
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#define np_info(np, fmt, ...) \
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pr_info("%s: " fmt, np->name, ##__VA_ARGS__)
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#define np_err(np, fmt, ...) \
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pr_err("%s: " fmt, np->name, ##__VA_ARGS__)
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#define np_notice(np, fmt, ...) \
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pr_notice("%s: " fmt, np->name, ##__VA_ARGS__)
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static void queue_process(struct work_struct *work)
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{
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struct netpoll_info *npinfo =
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container_of(work, struct netpoll_info, tx_work.work);
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struct sk_buff *skb;
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unsigned long flags;
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while ((skb = skb_dequeue(&npinfo->txq))) {
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struct net_device *dev = skb->dev;
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const struct net_device_ops *ops = dev->netdev_ops;
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struct netdev_queue *txq;
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if (!netif_device_present(dev) || !netif_running(dev)) {
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__kfree_skb(skb);
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continue;
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}
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txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
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local_irq_save(flags);
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__netif_tx_lock(txq, smp_processor_id());
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if (netif_xmit_frozen_or_stopped(txq) ||
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ops->ndo_start_xmit(skb, dev) != NETDEV_TX_OK) {
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skb_queue_head(&npinfo->txq, skb);
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__netif_tx_unlock(txq);
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local_irq_restore(flags);
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schedule_delayed_work(&npinfo->tx_work, HZ/10);
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return;
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}
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__netif_tx_unlock(txq);
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local_irq_restore(flags);
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}
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}
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static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,
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unsigned short ulen, __be32 saddr, __be32 daddr)
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{
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__wsum psum;
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if (uh->check == 0 || skb_csum_unnecessary(skb))
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return 0;
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psum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0);
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if (skb->ip_summed == CHECKSUM_COMPLETE &&
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!csum_fold(csum_add(psum, skb->csum)))
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return 0;
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skb->csum = psum;
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return __skb_checksum_complete(skb);
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}
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/*
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* Check whether delayed processing was scheduled for our NIC. If so,
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* we attempt to grab the poll lock and use ->poll() to pump the card.
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* If this fails, either we've recursed in ->poll() or it's already
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* running on another CPU.
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*
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* Note: we don't mask interrupts with this lock because we're using
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* trylock here and interrupts are already disabled in the softirq
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* case. Further, we test the poll_owner to avoid recursion on UP
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* systems where the lock doesn't exist.
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*
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* In cases where there is bi-directional communications, reading only
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* one message at a time can lead to packets being dropped by the
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* network adapter, forcing superfluous retries and possibly timeouts.
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* Thus, we set our budget to greater than 1.
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*/
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static int poll_one_napi(struct netpoll_info *npinfo,
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struct napi_struct *napi, int budget)
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{
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int work;
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/* net_rx_action's ->poll() invocations and our's are
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* synchronized by this test which is only made while
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* holding the napi->poll_lock.
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*/
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if (!test_bit(NAPI_STATE_SCHED, &napi->state))
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return budget;
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npinfo->rx_flags |= NETPOLL_RX_DROP;
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atomic_inc(&trapped);
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set_bit(NAPI_STATE_NPSVC, &napi->state);
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work = napi->poll(napi, budget);
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trace_napi_poll(napi);
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clear_bit(NAPI_STATE_NPSVC, &napi->state);
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atomic_dec(&trapped);
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npinfo->rx_flags &= ~NETPOLL_RX_DROP;
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return budget - work;
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}
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static void poll_napi(struct net_device *dev)
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{
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struct napi_struct *napi;
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int budget = 16;
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list_for_each_entry(napi, &dev->napi_list, dev_list) {
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if (napi->poll_owner != smp_processor_id() &&
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spin_trylock(&napi->poll_lock)) {
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budget = poll_one_napi(rcu_dereference_bh(dev->npinfo),
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napi, budget);
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spin_unlock(&napi->poll_lock);
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if (!budget)
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break;
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}
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}
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}
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static void service_neigh_queue(struct netpoll_info *npi)
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{
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if (npi) {
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struct sk_buff *skb;
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while ((skb = skb_dequeue(&npi->neigh_tx)))
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netpoll_neigh_reply(skb, npi);
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}
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}
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static void netpoll_poll_dev(struct net_device *dev)
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{
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const struct net_device_ops *ops;
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struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo);
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/* Don't do any rx activity if the dev_lock mutex is held
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* the dev_open/close paths use this to block netpoll activity
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* while changing device state
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*/
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if (down_trylock(&ni->dev_lock))
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return;
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if (!netif_running(dev)) {
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up(&ni->dev_lock);
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return;
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}
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ops = dev->netdev_ops;
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if (!ops->ndo_poll_controller) {
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up(&ni->dev_lock);
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return;
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}
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/* Process pending work on NIC */
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ops->ndo_poll_controller(dev);
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poll_napi(dev);
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up(&ni->dev_lock);
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if (dev->flags & IFF_SLAVE) {
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if (ni) {
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struct net_device *bond_dev;
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struct sk_buff *skb;
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struct netpoll_info *bond_ni;
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bond_dev = netdev_master_upper_dev_get_rcu(dev);
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bond_ni = rcu_dereference_bh(bond_dev->npinfo);
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while ((skb = skb_dequeue(&ni->neigh_tx))) {
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skb->dev = bond_dev;
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skb_queue_tail(&bond_ni->neigh_tx, skb);
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}
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}
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}
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service_neigh_queue(ni);
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zap_completion_queue();
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}
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void netpoll_rx_disable(struct net_device *dev)
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{
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struct netpoll_info *ni;
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int idx;
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might_sleep();
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idx = srcu_read_lock(&netpoll_srcu);
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ni = srcu_dereference(dev->npinfo, &netpoll_srcu);
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if (ni)
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down(&ni->dev_lock);
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srcu_read_unlock(&netpoll_srcu, idx);
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}
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EXPORT_SYMBOL(netpoll_rx_disable);
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void netpoll_rx_enable(struct net_device *dev)
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{
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struct netpoll_info *ni;
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rcu_read_lock();
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ni = rcu_dereference(dev->npinfo);
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if (ni)
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up(&ni->dev_lock);
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rcu_read_unlock();
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}
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EXPORT_SYMBOL(netpoll_rx_enable);
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static void refill_skbs(void)
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{
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struct sk_buff *skb;
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unsigned long flags;
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spin_lock_irqsave(&skb_pool.lock, flags);
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while (skb_pool.qlen < MAX_SKBS) {
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skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC);
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if (!skb)
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break;
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__skb_queue_tail(&skb_pool, skb);
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}
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spin_unlock_irqrestore(&skb_pool.lock, flags);
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}
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static void zap_completion_queue(void)
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{
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unsigned long flags;
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struct softnet_data *sd = &get_cpu_var(softnet_data);
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if (sd->completion_queue) {
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struct sk_buff *clist;
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local_irq_save(flags);
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clist = sd->completion_queue;
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sd->completion_queue = NULL;
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local_irq_restore(flags);
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while (clist != NULL) {
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struct sk_buff *skb = clist;
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clist = clist->next;
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if (skb->destructor) {
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atomic_inc(&skb->users);
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dev_kfree_skb_any(skb); /* put this one back */
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} else {
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__kfree_skb(skb);
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}
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}
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}
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put_cpu_var(softnet_data);
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}
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static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve)
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{
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int count = 0;
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struct sk_buff *skb;
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zap_completion_queue();
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refill_skbs();
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repeat:
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skb = alloc_skb(len, GFP_ATOMIC);
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if (!skb)
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skb = skb_dequeue(&skb_pool);
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if (!skb) {
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if (++count < 10) {
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netpoll_poll_dev(np->dev);
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goto repeat;
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}
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return NULL;
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}
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atomic_set(&skb->users, 1);
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skb_reserve(skb, reserve);
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return skb;
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}
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static int netpoll_owner_active(struct net_device *dev)
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{
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struct napi_struct *napi;
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list_for_each_entry(napi, &dev->napi_list, dev_list) {
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if (napi->poll_owner == smp_processor_id())
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return 1;
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}
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return 0;
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}
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/* call with IRQ disabled */
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void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
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struct net_device *dev)
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{
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int status = NETDEV_TX_BUSY;
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unsigned long tries;
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const struct net_device_ops *ops = dev->netdev_ops;
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/* It is up to the caller to keep npinfo alive. */
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struct netpoll_info *npinfo;
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WARN_ON_ONCE(!irqs_disabled());
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npinfo = rcu_dereference_bh(np->dev->npinfo);
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if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) {
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__kfree_skb(skb);
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return;
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}
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/* don't get messages out of order, and no recursion */
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if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) {
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struct netdev_queue *txq;
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txq = netdev_pick_tx(dev, skb);
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/* try until next clock tick */
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for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
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tries > 0; --tries) {
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if (__netif_tx_trylock(txq)) {
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if (!netif_xmit_stopped(txq)) {
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if (vlan_tx_tag_present(skb) &&
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!vlan_hw_offload_capable(netif_skb_features(skb),
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skb->vlan_proto)) {
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skb = __vlan_put_tag(skb, skb->vlan_proto, vlan_tx_tag_get(skb));
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if (unlikely(!skb))
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break;
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skb->vlan_tci = 0;
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}
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status = ops->ndo_start_xmit(skb, dev);
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if (status == NETDEV_TX_OK)
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txq_trans_update(txq);
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}
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__netif_tx_unlock(txq);
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if (status == NETDEV_TX_OK)
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break;
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}
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/* tickle device maybe there is some cleanup */
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netpoll_poll_dev(np->dev);
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udelay(USEC_PER_POLL);
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}
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WARN_ONCE(!irqs_disabled(),
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"netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pF)\n",
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dev->name, ops->ndo_start_xmit);
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}
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if (status != NETDEV_TX_OK) {
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skb_queue_tail(&npinfo->txq, skb);
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schedule_delayed_work(&npinfo->tx_work,0);
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}
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}
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EXPORT_SYMBOL(netpoll_send_skb_on_dev);
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void netpoll_send_udp(struct netpoll *np, const char *msg, int len)
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{
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int total_len, ip_len, udp_len;
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struct sk_buff *skb;
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struct udphdr *udph;
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struct iphdr *iph;
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struct ethhdr *eth;
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static atomic_t ip_ident;
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struct ipv6hdr *ip6h;
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udp_len = len + sizeof(*udph);
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if (np->ipv6)
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ip_len = udp_len + sizeof(*ip6h);
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else
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ip_len = udp_len + sizeof(*iph);
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total_len = ip_len + LL_RESERVED_SPACE(np->dev);
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skb = find_skb(np, total_len + np->dev->needed_tailroom,
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total_len - len);
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if (!skb)
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return;
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skb_copy_to_linear_data(skb, msg, len);
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skb_put(skb, len);
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skb_push(skb, sizeof(*udph));
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skb_reset_transport_header(skb);
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udph = udp_hdr(skb);
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udph->source = htons(np->local_port);
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udph->dest = htons(np->remote_port);
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udph->len = htons(udp_len);
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|
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if (np->ipv6) {
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udph->check = 0;
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udph->check = csum_ipv6_magic(&np->local_ip.in6,
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&np->remote_ip.in6,
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udp_len, IPPROTO_UDP,
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csum_partial(udph, udp_len, 0));
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if (udph->check == 0)
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udph->check = CSUM_MANGLED_0;
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|
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skb_push(skb, sizeof(*ip6h));
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skb_reset_network_header(skb);
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ip6h = ipv6_hdr(skb);
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/* ip6h->version = 6; ip6h->priority = 0; */
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put_unaligned(0x60, (unsigned char *)ip6h);
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ip6h->flow_lbl[0] = 0;
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ip6h->flow_lbl[1] = 0;
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ip6h->flow_lbl[2] = 0;
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|
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ip6h->payload_len = htons(sizeof(struct udphdr) + len);
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ip6h->nexthdr = IPPROTO_UDP;
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ip6h->hop_limit = 32;
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ip6h->saddr = np->local_ip.in6;
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ip6h->daddr = np->remote_ip.in6;
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|
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eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
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skb_reset_mac_header(skb);
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skb->protocol = eth->h_proto = htons(ETH_P_IPV6);
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} else {
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udph->check = 0;
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udph->check = csum_tcpudp_magic(np->local_ip.ip,
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np->remote_ip.ip,
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udp_len, IPPROTO_UDP,
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csum_partial(udph, udp_len, 0));
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if (udph->check == 0)
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udph->check = CSUM_MANGLED_0;
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skb_push(skb, sizeof(*iph));
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skb_reset_network_header(skb);
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iph = ip_hdr(skb);
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/* iph->version = 4; iph->ihl = 5; */
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put_unaligned(0x45, (unsigned char *)iph);
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iph->tos = 0;
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put_unaligned(htons(ip_len), &(iph->tot_len));
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iph->id = htons(atomic_inc_return(&ip_ident));
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iph->frag_off = 0;
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iph->ttl = 64;
|
|
iph->protocol = IPPROTO_UDP;
|
|
iph->check = 0;
|
|
put_unaligned(np->local_ip.ip, &(iph->saddr));
|
|
put_unaligned(np->remote_ip.ip, &(iph->daddr));
|
|
iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
|
|
|
|
eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
|
|
skb_reset_mac_header(skb);
|
|
skb->protocol = eth->h_proto = htons(ETH_P_IP);
|
|
}
|
|
|
|
memcpy(eth->h_source, np->dev->dev_addr, ETH_ALEN);
|
|
memcpy(eth->h_dest, np->remote_mac, ETH_ALEN);
|
|
|
|
skb->dev = np->dev;
|
|
|
|
netpoll_send_skb(np, skb);
|
|
}
|
|
EXPORT_SYMBOL(netpoll_send_udp);
|
|
|
|
static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo)
|
|
{
|
|
int size, type = ARPOP_REPLY;
|
|
__be32 sip, tip;
|
|
unsigned char *sha;
|
|
struct sk_buff *send_skb;
|
|
struct netpoll *np, *tmp;
|
|
unsigned long flags;
|
|
int hlen, tlen;
|
|
int hits = 0, proto;
|
|
|
|
if (list_empty(&npinfo->rx_np))
|
|
return;
|
|
|
|
/* Before checking the packet, we do some early
|
|
inspection whether this is interesting at all */
|
|
spin_lock_irqsave(&npinfo->rx_lock, flags);
|
|
list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
|
|
if (np->dev == skb->dev)
|
|
hits++;
|
|
}
|
|
spin_unlock_irqrestore(&npinfo->rx_lock, flags);
|
|
|
|
/* No netpoll struct is using this dev */
|
|
if (!hits)
|
|
return;
|
|
|
|
proto = ntohs(eth_hdr(skb)->h_proto);
|
|
if (proto == ETH_P_IP) {
|
|
struct arphdr *arp;
|
|
unsigned char *arp_ptr;
|
|
/* No arp on this interface */
|
|
if (skb->dev->flags & IFF_NOARP)
|
|
return;
|
|
|
|
if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
|
|
return;
|
|
|
|
skb_reset_network_header(skb);
|
|
skb_reset_transport_header(skb);
|
|
arp = arp_hdr(skb);
|
|
|
|
if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
|
|
arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
|
|
arp->ar_pro != htons(ETH_P_IP) ||
|
|
arp->ar_op != htons(ARPOP_REQUEST))
|
|
return;
|
|
|
|
arp_ptr = (unsigned char *)(arp+1);
|
|
/* save the location of the src hw addr */
|
|
sha = arp_ptr;
|
|
arp_ptr += skb->dev->addr_len;
|
|
memcpy(&sip, arp_ptr, 4);
|
|
arp_ptr += 4;
|
|
/* If we actually cared about dst hw addr,
|
|
it would get copied here */
|
|
arp_ptr += skb->dev->addr_len;
|
|
memcpy(&tip, arp_ptr, 4);
|
|
|
|
/* Should we ignore arp? */
|
|
if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip))
|
|
return;
|
|
|
|
size = arp_hdr_len(skb->dev);
|
|
|
|
spin_lock_irqsave(&npinfo->rx_lock, flags);
|
|
list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
|
|
if (tip != np->local_ip.ip)
|
|
continue;
|
|
|
|
hlen = LL_RESERVED_SPACE(np->dev);
|
|
tlen = np->dev->needed_tailroom;
|
|
send_skb = find_skb(np, size + hlen + tlen, hlen);
|
|
if (!send_skb)
|
|
continue;
|
|
|
|
skb_reset_network_header(send_skb);
|
|
arp = (struct arphdr *) skb_put(send_skb, size);
|
|
send_skb->dev = skb->dev;
|
|
send_skb->protocol = htons(ETH_P_ARP);
|
|
|
|
/* Fill the device header for the ARP frame */
|
|
if (dev_hard_header(send_skb, skb->dev, ETH_P_ARP,
|
|
sha, np->dev->dev_addr,
|
|
send_skb->len) < 0) {
|
|
kfree_skb(send_skb);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Fill out the arp protocol part.
|
|
*
|
|
* we only support ethernet device type,
|
|
* which (according to RFC 1390) should
|
|
* always equal 1 (Ethernet).
|
|
*/
|
|
|
|
arp->ar_hrd = htons(np->dev->type);
|
|
arp->ar_pro = htons(ETH_P_IP);
|
|
arp->ar_hln = np->dev->addr_len;
|
|
arp->ar_pln = 4;
|
|
arp->ar_op = htons(type);
|
|
|
|
arp_ptr = (unsigned char *)(arp + 1);
|
|
memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
|
|
arp_ptr += np->dev->addr_len;
|
|
memcpy(arp_ptr, &tip, 4);
|
|
arp_ptr += 4;
|
|
memcpy(arp_ptr, sha, np->dev->addr_len);
|
|
arp_ptr += np->dev->addr_len;
|
|
memcpy(arp_ptr, &sip, 4);
|
|
|
|
netpoll_send_skb(np, send_skb);
|
|
|
|
/* If there are several rx_hooks for the same address,
|
|
we're fine by sending a single reply */
|
|
break;
|
|
}
|
|
spin_unlock_irqrestore(&npinfo->rx_lock, flags);
|
|
} else if( proto == ETH_P_IPV6) {
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
struct nd_msg *msg;
|
|
u8 *lladdr = NULL;
|
|
struct ipv6hdr *hdr;
|
|
struct icmp6hdr *icmp6h;
|
|
const struct in6_addr *saddr;
|
|
const struct in6_addr *daddr;
|
|
struct inet6_dev *in6_dev = NULL;
|
|
struct in6_addr *target;
|
|
|
|
in6_dev = in6_dev_get(skb->dev);
|
|
if (!in6_dev || !in6_dev->cnf.accept_ra)
|
|
return;
|
|
|
|
if (!pskb_may_pull(skb, skb->len))
|
|
return;
|
|
|
|
msg = (struct nd_msg *)skb_transport_header(skb);
|
|
|
|
__skb_push(skb, skb->data - skb_transport_header(skb));
|
|
|
|
if (ipv6_hdr(skb)->hop_limit != 255)
|
|
return;
|
|
if (msg->icmph.icmp6_code != 0)
|
|
return;
|
|
if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
|
|
return;
|
|
|
|
saddr = &ipv6_hdr(skb)->saddr;
|
|
daddr = &ipv6_hdr(skb)->daddr;
|
|
|
|
size = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
|
|
|
|
spin_lock_irqsave(&npinfo->rx_lock, flags);
|
|
list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
|
|
unsigned long tail_offset;
|
|
|
|
if (!ipv6_addr_equal(daddr, &np->local_ip.in6))
|
|
continue;
|
|
|
|
hlen = LL_RESERVED_SPACE(np->dev);
|
|
tlen = np->dev->needed_tailroom;
|
|
send_skb = find_skb(np, size + hlen + tlen, hlen);
|
|
if (!send_skb)
|
|
continue;
|
|
|
|
send_skb->protocol = htons(ETH_P_IPV6);
|
|
send_skb->dev = skb->dev;
|
|
|
|
skb_reset_network_header(send_skb);
|
|
skb_put(send_skb, sizeof(struct ipv6hdr));
|
|
hdr = ipv6_hdr(send_skb);
|
|
|
|
*(__be32*)hdr = htonl(0x60000000);
|
|
|
|
hdr->payload_len = htons(size);
|
|
hdr->nexthdr = IPPROTO_ICMPV6;
|
|
hdr->hop_limit = 255;
|
|
hdr->saddr = *saddr;
|
|
hdr->daddr = *daddr;
|
|
|
|
tail_offset = skb_tail_offset(skb);
|
|
if (tail_offset > 0xffff) {
|
|
kfree_skb(send_skb);
|
|
continue;
|
|
}
|
|
skb_set_network_header(send_skb, tail_offset);
|
|
skb_put(send_skb, size);
|
|
|
|
icmp6h = (struct icmp6hdr *)skb_transport_header(skb);
|
|
icmp6h->icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
|
|
icmp6h->icmp6_router = 0;
|
|
icmp6h->icmp6_solicited = 1;
|
|
target = (struct in6_addr *)(skb_transport_header(send_skb) + sizeof(struct icmp6hdr));
|
|
*target = msg->target;
|
|
icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, size,
|
|
IPPROTO_ICMPV6,
|
|
csum_partial(icmp6h,
|
|
size, 0));
|
|
|
|
if (dev_hard_header(send_skb, skb->dev, ETH_P_IPV6,
|
|
lladdr, np->dev->dev_addr,
|
|
send_skb->len) < 0) {
|
|
kfree_skb(send_skb);
|
|
continue;
|
|
}
|
|
|
|
netpoll_send_skb(np, send_skb);
|
|
|
|
/* If there are several rx_hooks for the same address,
|
|
we're fine by sending a single reply */
|
|
break;
|
|
}
|
|
spin_unlock_irqrestore(&npinfo->rx_lock, flags);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
static bool pkt_is_ns(struct sk_buff *skb)
|
|
{
|
|
struct nd_msg *msg;
|
|
struct ipv6hdr *hdr;
|
|
|
|
if (skb->protocol != htons(ETH_P_ARP))
|
|
return false;
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + sizeof(struct nd_msg)))
|
|
return false;
|
|
|
|
msg = (struct nd_msg *)skb_transport_header(skb);
|
|
__skb_push(skb, skb->data - skb_transport_header(skb));
|
|
hdr = ipv6_hdr(skb);
|
|
|
|
if (hdr->nexthdr != IPPROTO_ICMPV6)
|
|
return false;
|
|
if (hdr->hop_limit != 255)
|
|
return false;
|
|
if (msg->icmph.icmp6_code != 0)
|
|
return false;
|
|
if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo)
|
|
{
|
|
int proto, len, ulen;
|
|
int hits = 0;
|
|
const struct iphdr *iph;
|
|
struct udphdr *uh;
|
|
struct netpoll *np, *tmp;
|
|
|
|
if (list_empty(&npinfo->rx_np))
|
|
goto out;
|
|
|
|
if (skb->dev->type != ARPHRD_ETHER)
|
|
goto out;
|
|
|
|
/* check if netpoll clients need ARP */
|
|
if (skb->protocol == htons(ETH_P_ARP) && atomic_read(&trapped)) {
|
|
skb_queue_tail(&npinfo->neigh_tx, skb);
|
|
return 1;
|
|
} else if (pkt_is_ns(skb) && atomic_read(&trapped)) {
|
|
skb_queue_tail(&npinfo->neigh_tx, skb);
|
|
return 1;
|
|
}
|
|
|
|
if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
|
|
skb = vlan_untag(skb);
|
|
if (unlikely(!skb))
|
|
goto out;
|
|
}
|
|
|
|
proto = ntohs(eth_hdr(skb)->h_proto);
|
|
if (proto != ETH_P_IP && proto != ETH_P_IPV6)
|
|
goto out;
|
|
if (skb->pkt_type == PACKET_OTHERHOST)
|
|
goto out;
|
|
if (skb_shared(skb))
|
|
goto out;
|
|
|
|
if (proto == ETH_P_IP) {
|
|
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
|
|
goto out;
|
|
iph = (struct iphdr *)skb->data;
|
|
if (iph->ihl < 5 || iph->version != 4)
|
|
goto out;
|
|
if (!pskb_may_pull(skb, iph->ihl*4))
|
|
goto out;
|
|
iph = (struct iphdr *)skb->data;
|
|
if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
|
|
goto out;
|
|
|
|
len = ntohs(iph->tot_len);
|
|
if (skb->len < len || len < iph->ihl*4)
|
|
goto out;
|
|
|
|
/*
|
|
* Our transport medium may have padded the buffer out.
|
|
* Now We trim to the true length of the frame.
|
|
*/
|
|
if (pskb_trim_rcsum(skb, len))
|
|
goto out;
|
|
|
|
iph = (struct iphdr *)skb->data;
|
|
if (iph->protocol != IPPROTO_UDP)
|
|
goto out;
|
|
|
|
len -= iph->ihl*4;
|
|
uh = (struct udphdr *)(((char *)iph) + iph->ihl*4);
|
|
ulen = ntohs(uh->len);
|
|
|
|
if (ulen != len)
|
|
goto out;
|
|
if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr))
|
|
goto out;
|
|
list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
|
|
if (np->local_ip.ip && np->local_ip.ip != iph->daddr)
|
|
continue;
|
|
if (np->remote_ip.ip && np->remote_ip.ip != iph->saddr)
|
|
continue;
|
|
if (np->local_port && np->local_port != ntohs(uh->dest))
|
|
continue;
|
|
|
|
np->rx_hook(np, ntohs(uh->source),
|
|
(char *)(uh+1),
|
|
ulen - sizeof(struct udphdr));
|
|
hits++;
|
|
}
|
|
} else {
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
const struct ipv6hdr *ip6h;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
|
|
goto out;
|
|
ip6h = (struct ipv6hdr *)skb->data;
|
|
if (ip6h->version != 6)
|
|
goto out;
|
|
len = ntohs(ip6h->payload_len);
|
|
if (!len)
|
|
goto out;
|
|
if (len + sizeof(struct ipv6hdr) > skb->len)
|
|
goto out;
|
|
if (pskb_trim_rcsum(skb, len + sizeof(struct ipv6hdr)))
|
|
goto out;
|
|
ip6h = ipv6_hdr(skb);
|
|
if (!pskb_may_pull(skb, sizeof(struct udphdr)))
|
|
goto out;
|
|
uh = udp_hdr(skb);
|
|
ulen = ntohs(uh->len);
|
|
if (ulen != skb->len)
|
|
goto out;
|
|
if (udp6_csum_init(skb, uh, IPPROTO_UDP))
|
|
goto out;
|
|
list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) {
|
|
if (!ipv6_addr_equal(&np->local_ip.in6, &ip6h->daddr))
|
|
continue;
|
|
if (!ipv6_addr_equal(&np->remote_ip.in6, &ip6h->saddr))
|
|
continue;
|
|
if (np->local_port && np->local_port != ntohs(uh->dest))
|
|
continue;
|
|
|
|
np->rx_hook(np, ntohs(uh->source),
|
|
(char *)(uh+1),
|
|
ulen - sizeof(struct udphdr));
|
|
hits++;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
if (!hits)
|
|
goto out;
|
|
|
|
kfree_skb(skb);
|
|
return 1;
|
|
|
|
out:
|
|
if (atomic_read(&trapped)) {
|
|
kfree_skb(skb);
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void netpoll_print_options(struct netpoll *np)
|
|
{
|
|
np_info(np, "local port %d\n", np->local_port);
|
|
if (np->ipv6)
|
|
np_info(np, "local IPv6 address %pI6c\n", &np->local_ip.in6);
|
|
else
|
|
np_info(np, "local IPv4 address %pI4\n", &np->local_ip.ip);
|
|
np_info(np, "interface '%s'\n", np->dev_name);
|
|
np_info(np, "remote port %d\n", np->remote_port);
|
|
if (np->ipv6)
|
|
np_info(np, "remote IPv6 address %pI6c\n", &np->remote_ip.in6);
|
|
else
|
|
np_info(np, "remote IPv4 address %pI4\n", &np->remote_ip.ip);
|
|
np_info(np, "remote ethernet address %pM\n", np->remote_mac);
|
|
}
|
|
EXPORT_SYMBOL(netpoll_print_options);
|
|
|
|
static int netpoll_parse_ip_addr(const char *str, union inet_addr *addr)
|
|
{
|
|
const char *end;
|
|
|
|
if (!strchr(str, ':') &&
|
|
in4_pton(str, -1, (void *)addr, -1, &end) > 0) {
|
|
if (!*end)
|
|
return 0;
|
|
}
|
|
if (in6_pton(str, -1, addr->in6.s6_addr, -1, &end) > 0) {
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
if (!*end)
|
|
return 1;
|
|
#else
|
|
return -1;
|
|
#endif
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
int netpoll_parse_options(struct netpoll *np, char *opt)
|
|
{
|
|
char *cur=opt, *delim;
|
|
int ipv6;
|
|
|
|
if (*cur != '@') {
|
|
if ((delim = strchr(cur, '@')) == NULL)
|
|
goto parse_failed;
|
|
*delim = 0;
|
|
if (kstrtou16(cur, 10, &np->local_port))
|
|
goto parse_failed;
|
|
cur = delim;
|
|
}
|
|
cur++;
|
|
|
|
if (*cur != '/') {
|
|
if ((delim = strchr(cur, '/')) == NULL)
|
|
goto parse_failed;
|
|
*delim = 0;
|
|
ipv6 = netpoll_parse_ip_addr(cur, &np->local_ip);
|
|
if (ipv6 < 0)
|
|
goto parse_failed;
|
|
else
|
|
np->ipv6 = (bool)ipv6;
|
|
cur = delim;
|
|
}
|
|
cur++;
|
|
|
|
if (*cur != ',') {
|
|
/* parse out dev name */
|
|
if ((delim = strchr(cur, ',')) == NULL)
|
|
goto parse_failed;
|
|
*delim = 0;
|
|
strlcpy(np->dev_name, cur, sizeof(np->dev_name));
|
|
cur = delim;
|
|
}
|
|
cur++;
|
|
|
|
if (*cur != '@') {
|
|
/* dst port */
|
|
if ((delim = strchr(cur, '@')) == NULL)
|
|
goto parse_failed;
|
|
*delim = 0;
|
|
if (*cur == ' ' || *cur == '\t')
|
|
np_info(np, "warning: whitespace is not allowed\n");
|
|
if (kstrtou16(cur, 10, &np->remote_port))
|
|
goto parse_failed;
|
|
cur = delim;
|
|
}
|
|
cur++;
|
|
|
|
/* dst ip */
|
|
if ((delim = strchr(cur, '/')) == NULL)
|
|
goto parse_failed;
|
|
*delim = 0;
|
|
ipv6 = netpoll_parse_ip_addr(cur, &np->remote_ip);
|
|
if (ipv6 < 0)
|
|
goto parse_failed;
|
|
else if (np->ipv6 != (bool)ipv6)
|
|
goto parse_failed;
|
|
else
|
|
np->ipv6 = (bool)ipv6;
|
|
cur = delim + 1;
|
|
|
|
if (*cur != 0) {
|
|
/* MAC address */
|
|
if (!mac_pton(cur, np->remote_mac))
|
|
goto parse_failed;
|
|
}
|
|
|
|
netpoll_print_options(np);
|
|
|
|
return 0;
|
|
|
|
parse_failed:
|
|
np_info(np, "couldn't parse config at '%s'!\n", cur);
|
|
return -1;
|
|
}
|
|
EXPORT_SYMBOL(netpoll_parse_options);
|
|
|
|
int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp)
|
|
{
|
|
struct netpoll_info *npinfo;
|
|
const struct net_device_ops *ops;
|
|
unsigned long flags;
|
|
int err;
|
|
|
|
np->dev = ndev;
|
|
strlcpy(np->dev_name, ndev->name, IFNAMSIZ);
|
|
INIT_WORK(&np->cleanup_work, netpoll_async_cleanup);
|
|
|
|
if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) ||
|
|
!ndev->netdev_ops->ndo_poll_controller) {
|
|
np_err(np, "%s doesn't support polling, aborting\n",
|
|
np->dev_name);
|
|
err = -ENOTSUPP;
|
|
goto out;
|
|
}
|
|
|
|
if (!ndev->npinfo) {
|
|
npinfo = kmalloc(sizeof(*npinfo), gfp);
|
|
if (!npinfo) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
npinfo->rx_flags = 0;
|
|
INIT_LIST_HEAD(&npinfo->rx_np);
|
|
|
|
spin_lock_init(&npinfo->rx_lock);
|
|
sema_init(&npinfo->dev_lock, 1);
|
|
skb_queue_head_init(&npinfo->neigh_tx);
|
|
skb_queue_head_init(&npinfo->txq);
|
|
INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
|
|
|
|
atomic_set(&npinfo->refcnt, 1);
|
|
|
|
ops = np->dev->netdev_ops;
|
|
if (ops->ndo_netpoll_setup) {
|
|
err = ops->ndo_netpoll_setup(ndev, npinfo, gfp);
|
|
if (err)
|
|
goto free_npinfo;
|
|
}
|
|
} else {
|
|
npinfo = rtnl_dereference(ndev->npinfo);
|
|
atomic_inc(&npinfo->refcnt);
|
|
}
|
|
|
|
npinfo->netpoll = np;
|
|
|
|
if (np->rx_hook) {
|
|
spin_lock_irqsave(&npinfo->rx_lock, flags);
|
|
npinfo->rx_flags |= NETPOLL_RX_ENABLED;
|
|
list_add_tail(&np->rx, &npinfo->rx_np);
|
|
spin_unlock_irqrestore(&npinfo->rx_lock, flags);
|
|
}
|
|
|
|
/* last thing to do is link it to the net device structure */
|
|
rcu_assign_pointer(ndev->npinfo, npinfo);
|
|
|
|
return 0;
|
|
|
|
free_npinfo:
|
|
kfree(npinfo);
|
|
out:
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__netpoll_setup);
|
|
|
|
int netpoll_setup(struct netpoll *np)
|
|
{
|
|
struct net_device *ndev = NULL;
|
|
struct in_device *in_dev;
|
|
int err;
|
|
|
|
rtnl_lock();
|
|
if (np->dev_name) {
|
|
struct net *net = current->nsproxy->net_ns;
|
|
ndev = __dev_get_by_name(net, np->dev_name);
|
|
}
|
|
if (!ndev) {
|
|
np_err(np, "%s doesn't exist, aborting\n", np->dev_name);
|
|
err = -ENODEV;
|
|
goto unlock;
|
|
}
|
|
dev_hold(ndev);
|
|
|
|
if (netdev_master_upper_dev_get(ndev)) {
|
|
np_err(np, "%s is a slave device, aborting\n", np->dev_name);
|
|
err = -EBUSY;
|
|
goto put;
|
|
}
|
|
|
|
if (!netif_running(ndev)) {
|
|
unsigned long atmost, atleast;
|
|
|
|
np_info(np, "device %s not up yet, forcing it\n", np->dev_name);
|
|
|
|
err = dev_open(ndev);
|
|
|
|
if (err) {
|
|
np_err(np, "failed to open %s\n", ndev->name);
|
|
goto put;
|
|
}
|
|
|
|
rtnl_unlock();
|
|
atleast = jiffies + HZ/10;
|
|
atmost = jiffies + carrier_timeout * HZ;
|
|
while (!netif_carrier_ok(ndev)) {
|
|
if (time_after(jiffies, atmost)) {
|
|
np_notice(np, "timeout waiting for carrier\n");
|
|
break;
|
|
}
|
|
msleep(1);
|
|
}
|
|
|
|
/* If carrier appears to come up instantly, we don't
|
|
* trust it and pause so that we don't pump all our
|
|
* queued console messages into the bitbucket.
|
|
*/
|
|
|
|
if (time_before(jiffies, atleast)) {
|
|
np_notice(np, "carrier detect appears untrustworthy, waiting 4 seconds\n");
|
|
msleep(4000);
|
|
}
|
|
rtnl_lock();
|
|
}
|
|
|
|
if (!np->local_ip.ip) {
|
|
if (!np->ipv6) {
|
|
in_dev = __in_dev_get_rtnl(ndev);
|
|
|
|
if (!in_dev || !in_dev->ifa_list) {
|
|
np_err(np, "no IP address for %s, aborting\n",
|
|
np->dev_name);
|
|
err = -EDESTADDRREQ;
|
|
goto put;
|
|
}
|
|
|
|
np->local_ip.ip = in_dev->ifa_list->ifa_local;
|
|
np_info(np, "local IP %pI4\n", &np->local_ip.ip);
|
|
} else {
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
struct inet6_dev *idev;
|
|
|
|
err = -EDESTADDRREQ;
|
|
idev = __in6_dev_get(ndev);
|
|
if (idev) {
|
|
struct inet6_ifaddr *ifp;
|
|
|
|
read_lock_bh(&idev->lock);
|
|
list_for_each_entry(ifp, &idev->addr_list, if_list) {
|
|
if (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)
|
|
continue;
|
|
np->local_ip.in6 = ifp->addr;
|
|
err = 0;
|
|
break;
|
|
}
|
|
read_unlock_bh(&idev->lock);
|
|
}
|
|
if (err) {
|
|
np_err(np, "no IPv6 address for %s, aborting\n",
|
|
np->dev_name);
|
|
goto put;
|
|
} else
|
|
np_info(np, "local IPv6 %pI6c\n", &np->local_ip.in6);
|
|
#else
|
|
np_err(np, "IPv6 is not supported %s, aborting\n",
|
|
np->dev_name);
|
|
err = -EINVAL;
|
|
goto put;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/* fill up the skb queue */
|
|
refill_skbs();
|
|
|
|
err = __netpoll_setup(np, ndev, GFP_KERNEL);
|
|
if (err)
|
|
goto put;
|
|
|
|
rtnl_unlock();
|
|
return 0;
|
|
|
|
put:
|
|
dev_put(ndev);
|
|
unlock:
|
|
rtnl_unlock();
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(netpoll_setup);
|
|
|
|
static int __init netpoll_init(void)
|
|
{
|
|
skb_queue_head_init(&skb_pool);
|
|
return 0;
|
|
}
|
|
core_initcall(netpoll_init);
|
|
|
|
static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head)
|
|
{
|
|
struct netpoll_info *npinfo =
|
|
container_of(rcu_head, struct netpoll_info, rcu);
|
|
|
|
skb_queue_purge(&npinfo->neigh_tx);
|
|
skb_queue_purge(&npinfo->txq);
|
|
|
|
/* we can't call cancel_delayed_work_sync here, as we are in softirq */
|
|
cancel_delayed_work(&npinfo->tx_work);
|
|
|
|
/* clean after last, unfinished work */
|
|
__skb_queue_purge(&npinfo->txq);
|
|
/* now cancel it again */
|
|
cancel_delayed_work(&npinfo->tx_work);
|
|
kfree(npinfo);
|
|
}
|
|
|
|
void __netpoll_cleanup(struct netpoll *np)
|
|
{
|
|
struct netpoll_info *npinfo;
|
|
unsigned long flags;
|
|
|
|
/* rtnl_dereference would be preferable here but
|
|
* rcu_cleanup_netpoll path can put us in here safely without
|
|
* holding the rtnl, so plain rcu_dereference it is
|
|
*/
|
|
npinfo = rtnl_dereference(np->dev->npinfo);
|
|
if (!npinfo)
|
|
return;
|
|
|
|
if (!list_empty(&npinfo->rx_np)) {
|
|
spin_lock_irqsave(&npinfo->rx_lock, flags);
|
|
list_del(&np->rx);
|
|
if (list_empty(&npinfo->rx_np))
|
|
npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
|
|
spin_unlock_irqrestore(&npinfo->rx_lock, flags);
|
|
}
|
|
|
|
synchronize_srcu(&netpoll_srcu);
|
|
|
|
if (atomic_dec_and_test(&npinfo->refcnt)) {
|
|
const struct net_device_ops *ops;
|
|
|
|
ops = np->dev->netdev_ops;
|
|
if (ops->ndo_netpoll_cleanup)
|
|
ops->ndo_netpoll_cleanup(np->dev);
|
|
|
|
rcu_assign_pointer(np->dev->npinfo, NULL);
|
|
call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(__netpoll_cleanup);
|
|
|
|
static void netpoll_async_cleanup(struct work_struct *work)
|
|
{
|
|
struct netpoll *np = container_of(work, struct netpoll, cleanup_work);
|
|
|
|
rtnl_lock();
|
|
__netpoll_cleanup(np);
|
|
rtnl_unlock();
|
|
kfree(np);
|
|
}
|
|
|
|
void __netpoll_free_async(struct netpoll *np)
|
|
{
|
|
schedule_work(&np->cleanup_work);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__netpoll_free_async);
|
|
|
|
void netpoll_cleanup(struct netpoll *np)
|
|
{
|
|
if (!np->dev)
|
|
return;
|
|
|
|
rtnl_lock();
|
|
__netpoll_cleanup(np);
|
|
rtnl_unlock();
|
|
|
|
dev_put(np->dev);
|
|
np->dev = NULL;
|
|
}
|
|
EXPORT_SYMBOL(netpoll_cleanup);
|
|
|
|
int netpoll_trap(void)
|
|
{
|
|
return atomic_read(&trapped);
|
|
}
|
|
EXPORT_SYMBOL(netpoll_trap);
|
|
|
|
void netpoll_set_trap(int trap)
|
|
{
|
|
if (trap)
|
|
atomic_inc(&trapped);
|
|
else
|
|
atomic_dec(&trapped);
|
|
}
|
|
EXPORT_SYMBOL(netpoll_set_trap);
|