/kernel/include/net/inetpeer.h
C Header | 186 lines | 133 code | 33 blank | 20 comment | 5 complexity | c95b15c2d5d016594ba52aa6d36333c8 MD5 | raw file
- /*
- * INETPEER - A storage for permanent information about peers
- *
- * Authors: Andrey V. Savochkin <saw@msu.ru>
- */
- #ifndef _NET_INETPEER_H
- #define _NET_INETPEER_H
- #include <linux/types.h>
- #include <linux/init.h>
- #include <linux/jiffies.h>
- #include <linux/spinlock.h>
- #include <linux/rtnetlink.h>
- #include <net/ipv6.h>
- #include <linux/atomic.h>
- struct inetpeer_addr_base {
- union {
- __be32 a4;
- __be32 a6[4];
- };
- };
- struct inetpeer_addr {
- struct inetpeer_addr_base addr;
- __u16 family;
- };
- struct inet_peer {
- /* group together avl_left,avl_right,v4daddr to speedup lookups */
- struct inet_peer __rcu *avl_left, *avl_right;
- struct inetpeer_addr daddr;
- __u32 avl_height;
- u32 metrics[RTAX_MAX];
- u32 rate_tokens; /* rate limiting for ICMP */
- unsigned long rate_last;
- union {
- struct list_head gc_list;
- struct rcu_head gc_rcu;
- };
- /*
- * Once inet_peer is queued for deletion (refcnt == -1), following fields
- * are not available: rid, ip_id_count
- * We can share memory with rcu_head to help keep inet_peer small.
- */
- union {
- struct {
- atomic_t rid; /* Frag reception counter */
- atomic_t ip_id_count; /* IP ID for the next packet */
- };
- struct rcu_head rcu;
- struct inet_peer *gc_next;
- };
- /* following fields might be frequently dirtied */
- __u32 dtime; /* the time of last use of not referenced entries */
- atomic_t refcnt;
- };
- struct inet_peer_base {
- struct inet_peer __rcu *root;
- seqlock_t lock;
- u32 flush_seq;
- int total;
- };
- #define INETPEER_BASE_BIT 0x1UL
- static inline struct inet_peer *inetpeer_ptr(unsigned long val)
- {
- BUG_ON(val & INETPEER_BASE_BIT);
- return (struct inet_peer *) val;
- }
- static inline struct inet_peer_base *inetpeer_base_ptr(unsigned long val)
- {
- if (!(val & INETPEER_BASE_BIT))
- return NULL;
- val &= ~INETPEER_BASE_BIT;
- return (struct inet_peer_base *) val;
- }
- static inline bool inetpeer_ptr_is_peer(unsigned long val)
- {
- return !(val & INETPEER_BASE_BIT);
- }
- static inline void __inetpeer_ptr_set_peer(unsigned long *val, struct inet_peer *peer)
- {
- /* This implicitly clears INETPEER_BASE_BIT */
- *val = (unsigned long) peer;
- }
- static inline bool inetpeer_ptr_set_peer(unsigned long *ptr, struct inet_peer *peer)
- {
- unsigned long val = (unsigned long) peer;
- unsigned long orig = *ptr;
- if (!(orig & INETPEER_BASE_BIT) ||
- cmpxchg(ptr, orig, val) != orig)
- return false;
- return true;
- }
- static inline void inetpeer_init_ptr(unsigned long *ptr, struct inet_peer_base *base)
- {
- *ptr = (unsigned long) base | INETPEER_BASE_BIT;
- }
- static inline void inetpeer_transfer_peer(unsigned long *to, unsigned long *from)
- {
- unsigned long val = *from;
- *to = val;
- if (inetpeer_ptr_is_peer(val)) {
- struct inet_peer *peer = inetpeer_ptr(val);
- atomic_inc(&peer->refcnt);
- }
- }
- extern void inet_peer_base_init(struct inet_peer_base *);
- void inet_initpeers(void) __init;
- #define INETPEER_METRICS_NEW (~(u32) 0)
- static inline bool inet_metrics_new(const struct inet_peer *p)
- {
- return p->metrics[RTAX_LOCK-1] == INETPEER_METRICS_NEW;
- }
- /* can be called with or without local BH being disabled */
- struct inet_peer *inet_getpeer(struct inet_peer_base *base,
- const struct inetpeer_addr *daddr,
- int create);
- static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
- __be32 v4daddr,
- int create)
- {
- struct inetpeer_addr daddr;
- daddr.addr.a4 = v4daddr;
- daddr.family = AF_INET;
- return inet_getpeer(base, &daddr, create);
- }
- static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
- const struct in6_addr *v6daddr,
- int create)
- {
- struct inetpeer_addr daddr;
- *(struct in6_addr *)daddr.addr.a6 = *v6daddr;
- daddr.family = AF_INET6;
- return inet_getpeer(base, &daddr, create);
- }
- /* can be called from BH context or outside */
- extern void inet_putpeer(struct inet_peer *p);
- extern bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
- extern void inetpeer_invalidate_tree(struct inet_peer_base *);
- extern void inetpeer_invalidate_family(int family);
- /*
- * temporary check to make sure we dont access rid, ip_id_count, tcp_ts,
- * tcp_ts_stamp if no refcount is taken on inet_peer
- */
- static inline void inet_peer_refcheck(const struct inet_peer *p)
- {
- WARN_ON_ONCE(atomic_read(&p->refcnt) <= 0);
- }
- /* can be called with or without local BH being disabled */
- static inline int inet_getid(struct inet_peer *p, int more)
- {
- more++;
- inet_peer_refcheck(p);
- return atomic_add_return(more, &p->ip_id_count) - more;
- }
- #endif /* _NET_INETPEER_H */