kernel-ark/include/linux/netpoll.h
David S. Miller d9452e9f81 [NETPOLL]: Revert two bogus cleanups that broke netconsole.
Based upon a report by Andrew Morton and code analysis done
by Jarek Poplawski.

This reverts 33f807ba0d ("[NETPOLL]:
Kill NETPOLL_RX_DROP, set but never tested.")  and
c7b6ea24b4 ("[NETPOLL]: Don't need
rx_flags.").

The rx_flags did get tested for zero vs. non-zero and therefore we do
need those tests and that code which sets NETPOLL_RX_DROP et al.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-04 12:28:49 -08:00

124 lines
2.7 KiB
C

/*
* Common code for low-level network console, dump, and debugger code
*
* Derived from netconsole, kgdb-over-ethernet, and netdump patches
*/
#ifndef _LINUX_NETPOLL_H
#define _LINUX_NETPOLL_H
#include <linux/netdevice.h>
#include <linux/interrupt.h>
#include <linux/rcupdate.h>
#include <linux/list.h>
struct netpoll {
struct net_device *dev;
char dev_name[IFNAMSIZ];
const char *name;
void (*rx_hook)(struct netpoll *, int, char *, int);
u32 local_ip, remote_ip;
u16 local_port, remote_port;
u8 remote_mac[ETH_ALEN];
};
struct netpoll_info {
atomic_t refcnt;
int rx_flags;
spinlock_t rx_lock;
struct netpoll *rx_np; /* netpoll that registered an rx_hook */
struct sk_buff_head arp_tx; /* list of arp requests to reply to */
struct sk_buff_head txq;
struct delayed_work tx_work;
};
void netpoll_poll(struct netpoll *np);
void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
void netpoll_print_options(struct netpoll *np);
int netpoll_parse_options(struct netpoll *np, char *opt);
int netpoll_setup(struct netpoll *np);
int netpoll_trap(void);
void netpoll_set_trap(int trap);
void netpoll_cleanup(struct netpoll *np);
int __netpoll_rx(struct sk_buff *skb);
#ifdef CONFIG_NETPOLL
static inline int netpoll_rx(struct sk_buff *skb)
{
struct netpoll_info *npinfo = skb->dev->npinfo;
unsigned long flags;
int ret = 0;
if (!npinfo || (!npinfo->rx_np && !npinfo->rx_flags))
return 0;
spin_lock_irqsave(&npinfo->rx_lock, flags);
/* check rx_flags again with the lock held */
if (npinfo->rx_flags && __netpoll_rx(skb))
ret = 1;
spin_unlock_irqrestore(&npinfo->rx_lock, flags);
return ret;
}
static inline int netpoll_receive_skb(struct sk_buff *skb)
{
if (!list_empty(&skb->dev->napi_list))
return netpoll_rx(skb);
return 0;
}
static inline void *netpoll_poll_lock(struct napi_struct *napi)
{
struct net_device *dev = napi->dev;
rcu_read_lock(); /* deal with race on ->npinfo */
if (dev && dev->npinfo) {
spin_lock(&napi->poll_lock);
napi->poll_owner = smp_processor_id();
return napi;
}
return NULL;
}
static inline void netpoll_poll_unlock(void *have)
{
struct napi_struct *napi = have;
if (napi) {
napi->poll_owner = -1;
spin_unlock(&napi->poll_lock);
}
rcu_read_unlock();
}
static inline void netpoll_netdev_init(struct net_device *dev)
{
INIT_LIST_HEAD(&dev->napi_list);
}
#else
static inline int netpoll_rx(struct sk_buff *skb)
{
return 0;
}
static inline int netpoll_receive_skb(struct sk_buff *skb)
{
return 0;
}
static inline void *netpoll_poll_lock(struct napi_struct *napi)
{
return NULL;
}
static inline void netpoll_poll_unlock(void *have)
{
}
static inline void netpoll_netdev_init(struct net_device *dev)
{
}
#endif
#endif