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/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Definitions for the IP router.
*
* Version: @(#)route.h 1.0.4 05/27/93
*
* Authors: Ross Biro, <bir7@leland.Stanford.Edu>
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Fixes:
* Alan Cox : Reformatted. Added ip_rt_local()
* Alan Cox : Support for TCP parameters.
* Alexey Kuznetsov: Major changes for new routing code.
*
* FIXME:
* Modules stuff is broken at the moment.
* Make atomic ops more generic and hide them in asm/...
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _ROUTE_H
#define _ROUTE_H
#include <linux/config.h>
/*
* 0 - no debugging messages
* 1 - rare events and bugs situations (default)
* 2 - trace mode.
*/
#define RT_CACHE_DEBUG 1
#define RT_HASH_DIVISOR 256
#define RT_CACHE_SIZE_MAX 256
#define RTZ_HASH_DIVISOR 256
#if RT_CACHE_DEBUG >= 2
#define RTZ_HASHING_LIMIT 0
#else
#define RTZ_HASHING_LIMIT 16
#endif
/*
* Maximal time to live for unused entry.
*/
#define RT_CACHE_TIMEOUT (HZ*300)
/*
* Prevents LRU trashing, entries considered equivalent,
* if the difference between last use times is less then this number.
*/
#define RT_CACHE_BUBBLE_THRESHOULD (HZ*5)
#include <linux/route.h>
#ifdef __KERNEL__
#define RTF_LOCAL 0x8000
#endif
/*
* Semaphores.
*/
#if defined(__alpha__)
static __inline__ void ATOMIC_INCR(unsigned int * addr)
{
unsigned tmp;
__asm__ __volatile__(
"1:\n\
ldl_l %1,%2\n\
addl %1,1,%1\n\
stl_c %1,%0\n\
beq %1,1b\n"
: "m=" (*addr), "r=&" (tmp)
: "m"(*addr));
}
static __inline__ void ATOMIC_DECR(unsigned int * addr)
{
unsigned tmp;
__asm__ __volatile__(
"1:\n\
ldl_l %1,%2\n\
subl %1,1,%1\n\
stl_c %1,%0\n\
beq %1,1b\n"
: "m=" (*addr), "r=&" (tmp)
: "m"(*addr));
}
static __inline__ int ATOMIC_DECR_AND_CHECK (unsigned int * addr)
{
unsigned tmp;
int result;
__asm__ __volatile__(
"1:\n\
ldl_l %1,%3\n\
subl %1,1,%1\n\
mov %1,%2\n\
stl_c %1,%0\n\
beq %1,1b\n"
: "m=" (*addr), "r=&" (tmp), "r=&"(result)
: "m"(*addr));
return result;
}
#elif defined(__i386__)
#include <asm/bitops.h>
extern __inline__ void ATOMIC_INCR(void * addr)
{
__asm__ __volatile__(
"incl %0"
:"=m" (ADDR));
}
extern __inline__ void ATOMIC_DECR(void * addr)
{
__asm__ __volatile__(
"decl %0"
:"=m" (ADDR));
}
/*
* It is DECR that is ATOMIC, not CHECK!
* If you want to do atomic checks, use cli()/sti(). --ANK
*/
extern __inline__ unsigned long ATOMIC_DECR_AND_CHECK(void * addr)
{
unsigned long retval;
__asm__ __volatile__(
"decl %0\nmovl %0,%1"
: "=m" (ADDR), "=r"(retval));
return retval;
}
#else
static __inline__ void ATOMIC_INCR(unsigned int * addr)
{
(*(__volatile__ unsigned int*)addr)++;
}
static __inline__ void ATOMIC_DECR(unsigned int * addr)
{
(*(__volatile__ unsigned int*)addr)--;
}
static __inline__ int ATOMIC_DECR_AND_CHECK (unsigned int * addr)
{
ATOMIC_DECR(addr);
return *(volatile unsigned int*)addr;
}
#endif
struct rtable
{
struct rtable *rt_next;
__u32 rt_dst;
__u32 rt_src;
__u32 rt_gateway;
unsigned rt_refcnt;
unsigned rt_use;
unsigned long rt_window;
unsigned long rt_lastuse;
struct hh_cache *rt_hh;
struct device *rt_dev;
unsigned short rt_flags;
unsigned short rt_mtu;
unsigned short rt_irtt;
unsigned char rt_tos;
};
extern void ip_rt_flush(struct device *dev);
extern void ip_rt_redirect(__u32 src, __u32 dst, __u32 gw, struct device *dev);
extern struct rtable *ip_rt_slow_route(__u32 daddr, int local);
extern int rt_get_info(char * buffer, char **start, off_t offset, int length, int dummy);
extern int rt_cache_get_info(char *buffer, char **start, off_t offset, int length, int dummy);
extern int ip_rt_ioctl(unsigned int cmd, void *arg);
extern int ip_rt_new(struct rtentry *rt);
extern void ip_rt_check_expire(void);
extern void ip_rt_advice(struct rtable **rp, int advice);
extern void ip_rt_run_bh(void);
extern int ip_rt_lock;
extern unsigned ip_rt_bh_mask;
extern struct rtable *ip_rt_hash_table[RT_HASH_DIVISOR];
extern __inline__ void ip_rt_fast_lock(void)
{
ATOMIC_INCR(&ip_rt_lock);
}
extern __inline__ void ip_rt_fast_unlock(void)
{
ATOMIC_DECR(&ip_rt_lock);
}
extern __inline__ void ip_rt_unlock(void)
{
if (!ATOMIC_DECR_AND_CHECK(&ip_rt_lock) && ip_rt_bh_mask)
ip_rt_run_bh();
}
extern __inline__ unsigned ip_rt_hash_code(__u32 addr)
{
unsigned tmp = addr + (addr>>16);
return (tmp + (tmp>>8)) & 0xFF;
}
extern __inline__ void ip_rt_put(struct rtable * rt)
#ifndef MODULE
{
if (rt)
ATOMIC_DECR(&rt->rt_refcnt);
}
#else
;
#endif
#ifdef CONFIG_KERNELD
extern struct rtable * ip_rt_route(__u32 daddr, int local);
#else
extern __inline__ struct rtable * ip_rt_route(__u32 daddr, int local)
#ifndef MODULE
{
struct rtable * rth;
ip_rt_fast_lock();
for (rth=ip_rt_hash_table[ip_rt_hash_code(daddr)^local]; rth; rth=rth->rt_next)
{
if (rth->rt_dst == daddr)
{
rth->rt_lastuse = jiffies;
ATOMIC_INCR(&rth->rt_use);
ATOMIC_INCR(&rth->rt_refcnt);
ip_rt_unlock();
return rth;
}
}
return ip_rt_slow_route (daddr, local);
}
#else
;
#endif
#endif
extern __inline__ struct rtable * ip_check_route(struct rtable ** rp,
__u32 daddr, int local)
{
struct rtable * rt = *rp;
if (!rt || rt->rt_dst != daddr || !(rt->rt_flags&RTF_UP)
|| ((local==1)^((rt->rt_flags&RTF_LOCAL) != 0)))
{
ip_rt_put(rt);
rt = ip_rt_route(daddr, local);
*rp = rt;
}
return rt;
}
#endif /* _ROUTE_H */
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