| 1 | /* |
| 2 | * Common code for low-level network console, dump, and debugger code |
| 3 | * |
| 4 | * Derived from netconsole, kgdb-over-ethernet, and netdump patches |
| 5 | */ |
| 6 | |
| 7 | #ifndef _LINUX_NETPOLL_H |
| 8 | #define _LINUX_NETPOLL_H |
| 9 | |
| 10 | #include <linux/netdevice.h> |
| 11 | #include <linux/interrupt.h> |
| 12 | #include <linux/rcupdate.h> |
| 13 | #include <linux/list.h> |
| 14 | |
| 15 | struct netpoll { |
| 16 | struct net_device *dev; |
| 17 | char dev_name[IFNAMSIZ]; |
| 18 | const char *name; |
| 19 | void (*rx_hook)(struct netpoll *, int, char *, int); |
| 20 | |
| 21 | __be32 local_ip, remote_ip; |
| 22 | u16 local_port, remote_port; |
| 23 | u8 remote_mac[ETH_ALEN]; |
| 24 | |
| 25 | struct list_head rx; /* rx_np list element */ |
| 26 | }; |
| 27 | |
| 28 | struct netpoll_info { |
| 29 | atomic_t refcnt; |
| 30 | |
| 31 | int rx_flags; |
| 32 | spinlock_t rx_lock; |
| 33 | struct list_head rx_np; /* netpolls that registered an rx_hook */ |
| 34 | |
| 35 | struct sk_buff_head arp_tx; /* list of arp requests to reply to */ |
| 36 | struct sk_buff_head txq; |
| 37 | |
| 38 | struct delayed_work tx_work; |
| 39 | |
| 40 | struct netpoll *netpoll; |
| 41 | }; |
| 42 | |
| 43 | void netpoll_send_udp(struct netpoll *np, const char *msg, int len); |
| 44 | void netpoll_print_options(struct netpoll *np); |
| 45 | int netpoll_parse_options(struct netpoll *np, char *opt); |
| 46 | int __netpoll_setup(struct netpoll *np); |
| 47 | int netpoll_setup(struct netpoll *np); |
| 48 | int netpoll_trap(void); |
| 49 | void netpoll_set_trap(int trap); |
| 50 | void __netpoll_cleanup(struct netpoll *np); |
| 51 | void netpoll_cleanup(struct netpoll *np); |
| 52 | int __netpoll_rx(struct sk_buff *skb); |
| 53 | void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, |
| 54 | struct net_device *dev); |
| 55 | static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) |
| 56 | { |
| 57 | netpoll_send_skb_on_dev(np, skb, np->dev); |
| 58 | } |
| 59 | |
| 60 | |
| 61 | |
| 62 | #ifdef CONFIG_NETPOLL |
| 63 | static inline bool netpoll_rx(struct sk_buff *skb) |
| 64 | { |
| 65 | struct netpoll_info *npinfo; |
| 66 | unsigned long flags; |
| 67 | bool ret = false; |
| 68 | |
| 69 | local_irq_save(flags); |
| 70 | npinfo = rcu_dereference_bh(skb->dev->npinfo); |
| 71 | |
| 72 | if (!npinfo || (list_empty(&npinfo->rx_np) && !npinfo->rx_flags)) |
| 73 | goto out; |
| 74 | |
| 75 | spin_lock(&npinfo->rx_lock); |
| 76 | /* check rx_flags again with the lock held */ |
| 77 | if (npinfo->rx_flags && __netpoll_rx(skb)) |
| 78 | ret = true; |
| 79 | spin_unlock(&npinfo->rx_lock); |
| 80 | |
| 81 | out: |
| 82 | local_irq_restore(flags); |
| 83 | return ret; |
| 84 | } |
| 85 | |
| 86 | static inline int netpoll_rx_on(struct sk_buff *skb) |
| 87 | { |
| 88 | struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo); |
| 89 | |
| 90 | return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags); |
| 91 | } |
| 92 | |
| 93 | static inline int netpoll_receive_skb(struct sk_buff *skb) |
| 94 | { |
| 95 | if (!list_empty(&skb->dev->napi_list)) |
| 96 | return netpoll_rx(skb); |
| 97 | return 0; |
| 98 | } |
| 99 | |
| 100 | static inline void *netpoll_poll_lock(struct napi_struct *napi) |
| 101 | { |
| 102 | struct net_device *dev = napi->dev; |
| 103 | |
| 104 | if (dev && dev->npinfo) { |
| 105 | spin_lock(&napi->poll_lock); |
| 106 | napi->poll_owner = smp_processor_id(); |
| 107 | return napi; |
| 108 | } |
| 109 | return NULL; |
| 110 | } |
| 111 | |
| 112 | static inline void netpoll_poll_unlock(void *have) |
| 113 | { |
| 114 | struct napi_struct *napi = have; |
| 115 | |
| 116 | if (napi) { |
| 117 | napi->poll_owner = -1; |
| 118 | spin_unlock(&napi->poll_lock); |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | static inline int netpoll_tx_running(struct net_device *dev) |
| 123 | { |
| 124 | return irqs_disabled(); |
| 125 | } |
| 126 | |
| 127 | #else |
| 128 | static inline bool netpoll_rx(struct sk_buff *skb) |
| 129 | { |
| 130 | return 0; |
| 131 | } |
| 132 | static inline int netpoll_rx_on(struct sk_buff *skb) |
| 133 | { |
| 134 | return 0; |
| 135 | } |
| 136 | static inline int netpoll_receive_skb(struct sk_buff *skb) |
| 137 | { |
| 138 | return 0; |
| 139 | } |
| 140 | static inline void *netpoll_poll_lock(struct napi_struct *napi) |
| 141 | { |
| 142 | return NULL; |
| 143 | } |
| 144 | static inline void netpoll_poll_unlock(void *have) |
| 145 | { |
| 146 | } |
| 147 | static inline void netpoll_netdev_init(struct net_device *dev) |
| 148 | { |
| 149 | } |
| 150 | static inline int netpoll_tx_running(struct net_device *dev) |
| 151 | { |
| 152 | return 0; |
| 153 | } |
| 154 | #endif |
| 155 | |
| 156 | #endif |