diff options
Diffstat (limited to 'kernel/include/net/inetpeer.h')
-rw-r--r-- | kernel/include/net/inetpeer.h | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/kernel/include/net/inetpeer.h b/kernel/include/net/inetpeer.h new file mode 100644 index 000000000..d5332ddce --- /dev/null +++ b/kernel/include/net/inetpeer.h @@ -0,0 +1,174 @@ +/* + * 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 in6_addr in6; + }; +}; + +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 field + * is not available: rid + * We can share memory with rcu_head to help keep inet_peer small. + */ + union { + struct { + atomic_t rid; /* Frag reception counter */ + }; + 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; + 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); + } +} + +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; + + daddr.addr.in6 = *v6daddr; + daddr.family = AF_INET6; + return inet_getpeer(base, &daddr, create); +} + +/* can be called from BH context or outside */ +void inet_putpeer(struct inet_peer *p); +bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout); + +void inetpeer_invalidate_tree(struct inet_peer_base *); + +/* + * temporary check to make sure we dont access rid, 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); +} +#endif /* _NET_INETPEER_H */ |