| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Common framework for low-level network console, dump, and debugger code |
| * |
| * Sep 8 2003 Matt Mackall <mpm@selenic.com> |
| * |
| * based on the netconsole code from: |
| * |
| * Copyright (C) 2001 Ingo Molnar <mingo@redhat.com> |
| * Copyright (C) 2002 Red Hat, Inc. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/moduleparam.h> |
| #include <linux/kernel.h> |
| #include <linux/netdevice.h> |
| #include <linux/etherdevice.h> |
| #include <linux/string.h> |
| #include <linux/if_arp.h> |
| #include <linux/inetdevice.h> |
| #include <linux/inet.h> |
| #include <linux/interrupt.h> |
| #include <linux/netpoll.h> |
| #include <linux/sched.h> |
| #include <linux/delay.h> |
| #include <linux/rcupdate.h> |
| #include <linux/workqueue.h> |
| #include <linux/slab.h> |
| #include <linux/export.h> |
| #include <linux/if_vlan.h> |
| #include <net/tcp.h> |
| #include <net/udp.h> |
| #include <net/addrconf.h> |
| #include <net/ndisc.h> |
| #include <net/ip6_checksum.h> |
| #include <asm/unaligned.h> |
| #include <trace/events/napi.h> |
| #include <linux/kconfig.h> |
| |
| /* |
| * We maintain a small pool of fully-sized skbs, to make sure the |
| * message gets out even in extreme OOM situations. |
| */ |
| |
| #define MAX_UDP_CHUNK 1460 |
| #define MAX_SKBS 32 |
| |
| static struct sk_buff_head skb_pool; |
| |
| DEFINE_STATIC_SRCU(netpoll_srcu); |
| |
| #define USEC_PER_POLL 50 |
| |
| #define MAX_SKB_SIZE \ |
| (sizeof(struct ethhdr) + \ |
| sizeof(struct iphdr) + \ |
| sizeof(struct udphdr) + \ |
| MAX_UDP_CHUNK) |
| |
| static void zap_completion_queue(void); |
| |
| static unsigned int carrier_timeout = 4; |
| module_param(carrier_timeout, uint, 0644); |
| |
| #define np_info(np, fmt, ...) \ |
| pr_info("%s: " fmt, np->name, ##__VA_ARGS__) |
| #define np_err(np, fmt, ...) \ |
| pr_err("%s: " fmt, np->name, ##__VA_ARGS__) |
| #define np_notice(np, fmt, ...) \ |
| pr_notice("%s: " fmt, np->name, ##__VA_ARGS__) |
| |
| static netdev_tx_t netpoll_start_xmit(struct sk_buff *skb, |
| struct net_device *dev, |
| struct netdev_queue *txq) |
| { |
| netdev_tx_t status = NETDEV_TX_OK; |
| netdev_features_t features; |
| |
| features = netif_skb_features(skb); |
| |
| if (skb_vlan_tag_present(skb) && |
| !vlan_hw_offload_capable(features, skb->vlan_proto)) { |
| skb = __vlan_hwaccel_push_inside(skb); |
| if (unlikely(!skb)) { |
| /* This is actually a packet drop, but we |
| * don't want the code that calls this |
| * function to try and operate on a NULL skb. |
| */ |
| goto out; |
| } |
| } |
| |
| status = netdev_start_xmit(skb, dev, txq, false); |
| |
| out: |
| return status; |
| } |
| |
| static void queue_process(struct work_struct *work) |
| { |
| struct netpoll_info *npinfo = |
| container_of(work, struct netpoll_info, tx_work.work); |
| struct sk_buff *skb; |
| unsigned long flags; |
| |
| while ((skb = skb_dequeue(&npinfo->txq))) { |
| struct net_device *dev = skb->dev; |
| struct netdev_queue *txq; |
| unsigned int q_index; |
| |
| if (!netif_device_present(dev) || !netif_running(dev)) { |
| kfree_skb(skb); |
| continue; |
| } |
| |
| local_irq_save(flags); |
| /* check if skb->queue_mapping is still valid */ |
| q_index = skb_get_queue_mapping(skb); |
| if (unlikely(q_index >= dev->real_num_tx_queues)) { |
| q_index = q_index % dev->real_num_tx_queues; |
| skb_set_queue_mapping(skb, q_index); |
| } |
| txq = netdev_get_tx_queue(dev, q_index); |
| HARD_TX_LOCK(dev, txq, smp_processor_id()); |
| if (netif_xmit_frozen_or_stopped(txq) || |
| !dev_xmit_complete(netpoll_start_xmit(skb, dev, txq))) { |
| skb_queue_head(&npinfo->txq, skb); |
| HARD_TX_UNLOCK(dev, txq); |
| local_irq_restore(flags); |
| |
| schedule_delayed_work(&npinfo->tx_work, HZ/10); |
| return; |
| } |
| HARD_TX_UNLOCK(dev, txq); |
| local_irq_restore(flags); |
| } |
| } |
| |
| static int netif_local_xmit_active(struct net_device *dev) |
| { |
| int i; |
| |
| for (i = 0; i < dev->num_tx_queues; i++) { |
| struct netdev_queue *txq = netdev_get_tx_queue(dev, i); |
| |
| if (READ_ONCE(txq->xmit_lock_owner) == smp_processor_id()) |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| static void poll_one_napi(struct napi_struct *napi) |
| { |
| int work; |
| |
| /* If we set this bit but see that it has already been set, |
| * that indicates that napi has been disabled and we need |
| * to abort this operation |
| */ |
| if (test_and_set_bit(NAPI_STATE_NPSVC, &napi->state)) |
| return; |
| |
| /* We explicilty pass the polling call a budget of 0 to |
| * indicate that we are clearing the Tx path only. |
| */ |
| work = napi->poll(napi, 0); |
| WARN_ONCE(work, "%pS exceeded budget in poll\n", napi->poll); |
| trace_napi_poll(napi, work, 0); |
| |
| clear_bit(NAPI_STATE_NPSVC, &napi->state); |
| } |
| |
| static void poll_napi(struct net_device *dev) |
| { |
| struct napi_struct *napi; |
| int cpu = smp_processor_id(); |
| |
| list_for_each_entry_rcu(napi, &dev->napi_list, dev_list) { |
| if (cmpxchg(&napi->poll_owner, -1, cpu) == -1) { |
| poll_one_napi(napi); |
| smp_store_release(&napi->poll_owner, -1); |
| } |
| } |
| } |
| |
| void netpoll_poll_dev(struct net_device *dev) |
| { |
| struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo); |
| const struct net_device_ops *ops; |
| |
| /* Don't do any rx activity if the dev_lock mutex is held |
| * the dev_open/close paths use this to block netpoll activity |
| * while changing device state |
| */ |
| if (!ni || down_trylock(&ni->dev_lock)) |
| return; |
| |
| /* Some drivers will take the same locks in poll and xmit, |
| * we can't poll if local CPU is already in xmit. |
| */ |
| if (!netif_running(dev) || netif_local_xmit_active(dev)) { |
| up(&ni->dev_lock); |
| return; |
| } |
| |
| ops = dev->netdev_ops; |
| if (ops->ndo_poll_controller) |
| ops->ndo_poll_controller(dev); |
| |
| poll_napi(dev); |
| |
| up(&ni->dev_lock); |
| |
| zap_completion_queue(); |
| } |
| EXPORT_SYMBOL(netpoll_poll_dev); |
| |
| void netpoll_poll_disable(struct net_device *dev) |
| { |
| struct netpoll_info *ni; |
| int idx; |
| might_sleep(); |
| idx = srcu_read_lock(&netpoll_srcu); |
| ni = srcu_dereference(dev->npinfo, &netpoll_srcu); |
| if (ni) |
| down(&ni->dev_lock); |
| srcu_read_unlock(&netpoll_srcu, idx); |
| } |
| EXPORT_SYMBOL(netpoll_poll_disable); |
| |
| void netpoll_poll_enable(struct net_device *dev) |
| { |
| struct netpoll_info *ni; |
| rcu_read_lock(); |
| ni = rcu_dereference(dev->npinfo); |
| if (ni) |
| up(&ni->dev_lock); |
| rcu_read_unlock(); |
| } |
| EXPORT_SYMBOL(netpoll_poll_enable); |
| |
| static void refill_skbs(void) |
| { |
| struct sk_buff *skb; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&skb_pool.lock, flags); |
| while (skb_pool.qlen < MAX_SKBS) { |
| skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC); |
| if (!skb) |
| break; |
| |
| __skb_queue_tail(&skb_pool, skb); |
| } |
| spin_unlock_irqrestore(&skb_pool.lock, flags); |
| } |
| |
| static void zap_completion_queue(void) |
| { |
| unsigned long flags; |
| struct softnet_data *sd = &get_cpu_var(softnet_data); |
| |
| if (sd->completion_queue) { |
| struct sk_buff *clist; |
| |
| local_irq_save(flags); |
| clist = sd->completion_queue; |
| sd->completion_queue = NULL; |
| local_irq_restore(flags); |
| |
| while (clist != NULL) { |
| struct sk_buff *skb = clist; |
| clist = clist->next; |
| if (!skb_irq_freeable(skb)) { |
| refcount_set(&skb->users, 1); |
| dev_kfree_skb_any(skb); /* put this one back */ |
| } else { |
| __kfree_skb(skb); |
| } |
| } |
| } |
| |
| put_cpu_var(softnet_data); |
| } |
| |
| static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve) |
| { |
| int count = 0; |
| struct sk_buff *skb; |
| |
| zap_completion_queue(); |
| refill_skbs(); |
| repeat: |
| |
| skb = alloc_skb(len, GFP_ATOMIC); |
| if (!skb) |
| skb = skb_dequeue(&skb_pool); |
| |
| if (!skb) { |
| if (++count < 10) { |
| netpoll_poll_dev(np->dev); |
| goto repeat; |
| } |
| return NULL; |
| } |
| |
| refcount_set(&skb->users, 1); |
| skb_reserve(skb, reserve); |
| return skb; |
| } |
| |
| static int netpoll_owner_active(struct net_device *dev) |
| { |
| struct napi_struct *napi; |
| |
| list_for_each_entry_rcu(napi, &dev->napi_list, dev_list) { |
| if (napi->poll_owner == smp_processor_id()) |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* call with IRQ disabled */ |
| static netdev_tx_t __netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) |
| { |
| netdev_tx_t status = NETDEV_TX_BUSY; |
| struct net_device *dev; |
| unsigned long tries; |
| /* It is up to the caller to keep npinfo alive. */ |
| struct netpoll_info *npinfo; |
| |
| lockdep_assert_irqs_disabled(); |
| |
| dev = np->dev; |
| npinfo = rcu_dereference_bh(dev->npinfo); |
| |
| if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) { |
| dev_kfree_skb_irq(skb); |
| return NET_XMIT_DROP; |
| } |
| |
| /* don't get messages out of order, and no recursion */ |
| if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) { |
| struct netdev_queue *txq; |
| |
| txq = netdev_core_pick_tx(dev, skb, NULL); |
| |
| /* try until next clock tick */ |
| for (tries = jiffies_to_usecs(1)/USEC_PER_POLL; |
| tries > 0; --tries) { |
| if (HARD_TX_TRYLOCK(dev, txq)) { |
| if (!netif_xmit_stopped(txq)) |
| status = netpoll_start_xmit(skb, dev, txq); |
| |
| HARD_TX_UNLOCK(dev, txq); |
| |
| if (dev_xmit_complete(status)) |
| break; |
| |
| } |
| |
| /* tickle device maybe there is some cleanup */ |
| netpoll_poll_dev(np->dev); |
| |
| udelay(USEC_PER_POLL); |
| } |
| |
| WARN_ONCE(!irqs_disabled(), |
| "netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pS)\n", |
| dev->name, dev->netdev_ops->ndo_start_xmit); |
| |
| } |
| |
| if (!dev_xmit_complete(status)) { |
| skb_queue_tail(&npinfo->txq, skb); |
| schedule_delayed_work(&npinfo->tx_work,0); |
| } |
| return NETDEV_TX_OK; |
| } |
| |
| netdev_tx_t netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) |
| { |
| unsigned long flags; |
| netdev_tx_t ret; |
| |
| if (unlikely(!np)) { |
| dev_kfree_skb_irq(skb); |
| ret = NET_XMIT_DROP; |
| } else { |
| local_irq_save(flags); |
| ret = __netpoll_send_skb(np, skb); |
| local_irq_restore(flags); |
| } |
| return ret; |
| } |
| EXPORT_SYMBOL(netpoll_send_skb); |
| |
| void netpoll_send_udp(struct netpoll *np, const char *msg, int len) |
| { |
| int total_len, ip_len, udp_len; |
| struct sk_buff *skb; |
| struct udphdr *udph; |
| struct iphdr *iph; |
| struct ethhdr *eth; |
| static atomic_t ip_ident; |
| struct ipv6hdr *ip6h; |
| |
| if (!IS_ENABLED(CONFIG_PREEMPT_RT)) |
| WARN_ON_ONCE(!irqs_disabled()); |
| |
| udp_len = len + sizeof(*udph); |
| if (np->ipv6) |
| ip_len = udp_len + sizeof(*ip6h); |
| else |
| ip_len = udp_len + sizeof(*iph); |
| |
| total_len = ip_len + LL_RESERVED_SPACE(np->dev); |
| |
| skb = find_skb(np, total_len + np->dev->needed_tailroom, |
| total_len - len); |
| if (!skb) |
| return; |
| |
| skb_copy_to_linear_data(skb, msg, len); |
| skb_put(skb, len); |
| |
| skb_push(skb, sizeof(*udph)); |
| skb_reset_transport_header(skb); |
| udph = udp_hdr(skb); |
| udph->source = htons(np->local_port); |
| udph->dest = htons(np->remote_port); |
| udph->len = htons(udp_len); |
| |
| if (np->ipv6) { |
| udph->check = 0; |
| udph->check = csum_ipv6_magic(&np->local_ip.in6, |
| &np->remote_ip.in6, |
| udp_len, IPPROTO_UDP, |
| csum_partial(udph, udp_len, 0)); |
| if (udph->check == 0) |
| udph->check = CSUM_MANGLED_0; |
| |
| skb_push(skb, sizeof(*ip6h)); |
| skb_reset_network_header(skb); |
| ip6h = ipv6_hdr(skb); |
| |
| /* ip6h->version = 6; ip6h->priority = 0; */ |
| *(unsigned char *)ip6h = 0x60; |
| ip6h->flow_lbl[0] = 0; |
| ip6h->flow_lbl[1] = 0; |
| ip6h->flow_lbl[2] = 0; |
| |
| ip6h->payload_len = htons(sizeof(struct udphdr) + len); |
| ip6h->nexthdr = IPPROTO_UDP; |
| ip6h->hop_limit = 32; |
| ip6h->saddr = np->local_ip.in6; |
| ip6h->daddr = np->remote_ip.in6; |
| |
| eth = skb_push(skb, ETH_HLEN); |
| skb_reset_mac_header(skb); |
| skb->protocol = eth->h_proto = htons(ETH_P_IPV6); |
| } else { |
| udph->check = 0; |
| udph->check = csum_tcpudp_magic(np->local_ip.ip, |
| np->remote_ip.ip, |
| udp_len, IPPROTO_UDP, |
| csum_partial(udph, udp_len, 0)); |
| if (udph->check == 0) |
| udph->check = CSUM_MANGLED_0; |
| |
| skb_push(skb, sizeof(*iph)); |
| skb_reset_network_header(skb); |
| iph = ip_hdr(skb); |
| |
| /* iph->version = 4; iph->ihl = 5; */ |
| *(unsigned char *)iph = 0x45; |
| iph->tos = 0; |
| put_unaligned(htons(ip_len), &(iph->tot_len)); |
| iph->id = htons(atomic_inc_return(&ip_ident)); |
| iph->frag_off = 0; |
| 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 = skb_push(skb, ETH_HLEN); |
| skb_reset_mac_header(skb); |
| skb->protocol = eth->h_proto = htons(ETH_P_IP); |
| } |
| |
| ether_addr_copy(eth->h_source, np->dev->dev_addr); |
| ether_addr_copy(eth->h_dest, np->remote_mac); |
| |
| skb->dev = np->dev; |
| |
| netpoll_send_skb(np, skb); |
| } |
| EXPORT_SYMBOL(netpoll_send_udp); |
| |
| 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; |
| bool ipversion_set = false; |
| |
| 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 != '/') { |
| ipversion_set = true; |
| 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; |
| strscpy(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 (ipversion_set && 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) |
| { |
| struct netpoll_info *npinfo; |
| const struct net_device_ops *ops; |
| int err; |
| |
| np->dev = ndev; |
| strscpy(np->dev_name, ndev->name, IFNAMSIZ); |
| |
| if (ndev->priv_flags & IFF_DISABLE_NETPOLL) { |
| 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_KERNEL); |
| if (!npinfo) { |
| err = -ENOMEM; |
| goto out; |
| } |
| |
| sema_init(&npinfo->dev_lock, 1); |
| skb_queue_head_init(&npinfo->txq); |
| INIT_DELAYED_WORK(&npinfo->tx_work, queue_process); |
| |
| refcount_set(&npinfo->refcnt, 1); |
| |
| ops = np->dev->netdev_ops; |
| if (ops->ndo_netpoll_setup) { |
| err = ops->ndo_netpoll_setup(ndev, npinfo); |
| if (err) |
| goto free_npinfo; |
| } |
| } else { |
| npinfo = rtnl_dereference(ndev->npinfo); |
| refcount_inc(&npinfo->refcnt); |
| } |
| |
| npinfo->netpoll = np; |
| |
| /* 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[0]) { |
| 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, NULL); |
| |
| 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) { |
| const struct in_ifaddr *ifa; |
| |
| in_dev = __in_dev_get_rtnl(ndev); |
| if (!in_dev) |
| goto put_noaddr; |
| |
| ifa = rtnl_dereference(in_dev->ifa_list); |
| if (!ifa) { |
| put_noaddr: |
| np_err(np, "no IP address for %s, aborting\n", |
| np->dev_name); |
| err = -EDESTADDRREQ; |
| goto put; |
| } |
| |
| np->local_ip.ip = ifa->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) != |
| !!(ipv6_addr_type(&np->remote_ip.in6) & 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); |
| 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->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; |
| |
| npinfo = rtnl_dereference(np->dev->npinfo); |
| if (!npinfo) |
| return; |
| |
| synchronize_srcu(&netpoll_srcu); |
| |
| if (refcount_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_INIT_POINTER(np->dev->npinfo, NULL); |
| call_rcu(&npinfo->rcu, rcu_cleanup_netpoll_info); |
| } else |
| RCU_INIT_POINTER(np->dev->npinfo, NULL); |
| } |
| EXPORT_SYMBOL_GPL(__netpoll_cleanup); |
| |
| void __netpoll_free(struct netpoll *np) |
| { |
| ASSERT_RTNL(); |
| |
| /* Wait for transmitting packets to finish before freeing. */ |
| synchronize_rcu(); |
| __netpoll_cleanup(np); |
| kfree(np); |
| } |
| EXPORT_SYMBOL_GPL(__netpoll_free); |
| |
| void netpoll_cleanup(struct netpoll *np) |
| { |
| rtnl_lock(); |
| if (!np->dev) |
| goto out; |
| __netpoll_cleanup(np); |
| dev_put(np->dev); |
| np->dev = NULL; |
| out: |
| rtnl_unlock(); |
| } |
| EXPORT_SYMBOL(netpoll_cleanup); |