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authorSamuel Thibault <samuel.thibault@ens-lyon.org>2013-07-27 22:15:01 +0000
committerSamuel Thibault <samuel.thibault@ens-lyon.org>2013-07-27 22:15:01 +0000
commit7996a3d79d55b7f879dfd62e202bbfe2963718d3 (patch)
tree8d9f6759fec4099b9be503c11c7ed174f7204980 /libdde-linux26/contrib/include/net/inet_hashtables.h
parent4fbe7358c7747a9165f776eb19addbb9baf7def2 (diff)
really properly move files
Diffstat (limited to 'libdde-linux26/contrib/include/net/inet_hashtables.h')
-rw-r--r--libdde-linux26/contrib/include/net/inet_hashtables.h398
1 files changed, 398 insertions, 0 deletions
diff --git a/libdde-linux26/contrib/include/net/inet_hashtables.h b/libdde-linux26/contrib/include/net/inet_hashtables.h
new file mode 100644
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+++ b/libdde-linux26/contrib/include/net/inet_hashtables.h
@@ -0,0 +1,398 @@
+/*
+ * 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.
+ *
+ * Authors: Lotsa people, from code originally in tcp
+ *
+ * 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 _INET_HASHTABLES_H
+#define _INET_HASHTABLES_H
+
+
+#include <linux/interrupt.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/socket.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+#include <linux/vmalloc.h>
+
+#include <net/inet_connection_sock.h>
+#include <net/inet_sock.h>
+#include <net/sock.h>
+#include <net/route.h>
+#include <net/tcp_states.h>
+#include <net/netns/hash.h>
+
+#include <asm/atomic.h>
+#include <asm/byteorder.h>
+
+/* This is for all connections with a full identity, no wildcards.
+ * One chain is dedicated to TIME_WAIT sockets.
+ * I'll experiment with dynamic table growth later.
+ */
+struct inet_ehash_bucket {
+ struct hlist_nulls_head chain;
+ struct hlist_nulls_head twchain;
+};
+
+/* There are a few simple rules, which allow for local port reuse by
+ * an application. In essence:
+ *
+ * 1) Sockets bound to different interfaces may share a local port.
+ * Failing that, goto test 2.
+ * 2) If all sockets have sk->sk_reuse set, and none of them are in
+ * TCP_LISTEN state, the port may be shared.
+ * Failing that, goto test 3.
+ * 3) If all sockets are bound to a specific inet_sk(sk)->rcv_saddr local
+ * address, and none of them are the same, the port may be
+ * shared.
+ * Failing this, the port cannot be shared.
+ *
+ * The interesting point, is test #2. This is what an FTP server does
+ * all day. To optimize this case we use a specific flag bit defined
+ * below. As we add sockets to a bind bucket list, we perform a
+ * check of: (newsk->sk_reuse && (newsk->sk_state != TCP_LISTEN))
+ * As long as all sockets added to a bind bucket pass this test,
+ * the flag bit will be set.
+ * The resulting situation is that tcp_v[46]_verify_bind() can just check
+ * for this flag bit, if it is set and the socket trying to bind has
+ * sk->sk_reuse set, we don't even have to walk the owners list at all,
+ * we return that it is ok to bind this socket to the requested local port.
+ *
+ * Sounds like a lot of work, but it is worth it. In a more naive
+ * implementation (ie. current FreeBSD etc.) the entire list of ports
+ * must be walked for each data port opened by an ftp server. Needless
+ * to say, this does not scale at all. With a couple thousand FTP
+ * users logged onto your box, isn't it nice to know that new data
+ * ports are created in O(1) time? I thought so. ;-) -DaveM
+ */
+struct inet_bind_bucket {
+#ifdef CONFIG_NET_NS
+ struct net *ib_net;
+#endif
+ unsigned short port;
+ signed short fastreuse;
+ struct hlist_node node;
+ struct hlist_head owners;
+};
+
+static inline struct net *ib_net(struct inet_bind_bucket *ib)
+{
+ return read_pnet(&ib->ib_net);
+}
+
+#define inet_bind_bucket_for_each(tb, node, head) \
+ hlist_for_each_entry(tb, node, head, node)
+
+struct inet_bind_hashbucket {
+ spinlock_t lock;
+ struct hlist_head chain;
+};
+
+/*
+ * Sockets can be hashed in established or listening table
+ * We must use different 'nulls' end-of-chain value for listening
+ * hash table, or we might find a socket that was closed and
+ * reallocated/inserted into established hash table
+ */
+#define LISTENING_NULLS_BASE (1U << 29)
+struct inet_listen_hashbucket {
+ spinlock_t lock;
+ struct hlist_nulls_head head;
+};
+
+/* This is for listening sockets, thus all sockets which possess wildcards. */
+#define INET_LHTABLE_SIZE 32 /* Yes, really, this is all you need. */
+
+struct inet_hashinfo {
+ /* This is for sockets with full identity only. Sockets here will
+ * always be without wildcards and will have the following invariant:
+ *
+ * TCP_ESTABLISHED <= sk->sk_state < TCP_CLOSE
+ *
+ * TIME_WAIT sockets use a separate chain (twchain).
+ */
+ struct inet_ehash_bucket *ehash;
+ spinlock_t *ehash_locks;
+ unsigned int ehash_size;
+ unsigned int ehash_locks_mask;
+
+ /* Ok, let's try this, I give up, we do need a local binding
+ * TCP hash as well as the others for fast bind/connect.
+ */
+ struct inet_bind_hashbucket *bhash;
+
+ unsigned int bhash_size;
+ /* Note : 4 bytes padding on 64 bit arches */
+
+ struct kmem_cache *bind_bucket_cachep;
+
+ /* All the above members are written once at bootup and
+ * never written again _or_ are predominantly read-access.
+ *
+ * Now align to a new cache line as all the following members
+ * might be often dirty.
+ */
+ /* All sockets in TCP_LISTEN state will be in here. This is the only
+ * table where wildcard'd TCP sockets can exist. Hash function here
+ * is just local port number.
+ */
+ struct inet_listen_hashbucket listening_hash[INET_LHTABLE_SIZE]
+ ____cacheline_aligned_in_smp;
+
+};
+
+static inline struct inet_ehash_bucket *inet_ehash_bucket(
+ struct inet_hashinfo *hashinfo,
+ unsigned int hash)
+{
+ return &hashinfo->ehash[hash & (hashinfo->ehash_size - 1)];
+}
+
+static inline spinlock_t *inet_ehash_lockp(
+ struct inet_hashinfo *hashinfo,
+ unsigned int hash)
+{
+ return &hashinfo->ehash_locks[hash & hashinfo->ehash_locks_mask];
+}
+
+static inline int inet_ehash_locks_alloc(struct inet_hashinfo *hashinfo)
+{
+ unsigned int i, size = 256;
+#if defined(CONFIG_PROVE_LOCKING)
+ unsigned int nr_pcpus = 2;
+#else
+ unsigned int nr_pcpus = num_possible_cpus();
+#endif
+ if (nr_pcpus >= 4)
+ size = 512;
+ if (nr_pcpus >= 8)
+ size = 1024;
+ if (nr_pcpus >= 16)
+ size = 2048;
+ if (nr_pcpus >= 32)
+ size = 4096;
+ if (sizeof(spinlock_t) != 0) {
+#ifdef CONFIG_NUMA
+ if (size * sizeof(spinlock_t) > PAGE_SIZE)
+ hashinfo->ehash_locks = vmalloc(size * sizeof(spinlock_t));
+ else
+#endif
+ hashinfo->ehash_locks = kmalloc(size * sizeof(spinlock_t),
+ GFP_KERNEL);
+ if (!hashinfo->ehash_locks)
+ return ENOMEM;
+ for (i = 0; i < size; i++)
+ spin_lock_init(&hashinfo->ehash_locks[i]);
+ }
+ hashinfo->ehash_locks_mask = size - 1;
+ return 0;
+}
+
+static inline void inet_ehash_locks_free(struct inet_hashinfo *hashinfo)
+{
+ if (hashinfo->ehash_locks) {
+#ifdef CONFIG_NUMA
+ unsigned int size = (hashinfo->ehash_locks_mask + 1) *
+ sizeof(spinlock_t);
+ if (size > PAGE_SIZE)
+ vfree(hashinfo->ehash_locks);
+ else
+#endif
+ kfree(hashinfo->ehash_locks);
+ hashinfo->ehash_locks = NULL;
+ }
+}
+
+extern struct inet_bind_bucket *
+ inet_bind_bucket_create(struct kmem_cache *cachep,
+ struct net *net,
+ struct inet_bind_hashbucket *head,
+ const unsigned short snum);
+extern void inet_bind_bucket_destroy(struct kmem_cache *cachep,
+ struct inet_bind_bucket *tb);
+
+static inline int inet_bhashfn(struct net *net,
+ const __u16 lport, const int bhash_size)
+{
+ return (lport + net_hash_mix(net)) & (bhash_size - 1);
+}
+
+extern void inet_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
+ const unsigned short snum);
+
+/* These can have wildcards, don't try too hard. */
+static inline int inet_lhashfn(struct net *net, const unsigned short num)
+{
+ return (num + net_hash_mix(net)) & (INET_LHTABLE_SIZE - 1);
+}
+
+static inline int inet_sk_listen_hashfn(const struct sock *sk)
+{
+ return inet_lhashfn(sock_net(sk), inet_sk(sk)->num);
+}
+
+/* Caller must disable local BH processing. */
+extern void __inet_inherit_port(struct sock *sk, struct sock *child);
+
+extern void inet_put_port(struct sock *sk);
+
+void inet_hashinfo_init(struct inet_hashinfo *h);
+
+extern void __inet_hash_nolisten(struct sock *sk);
+extern void inet_hash(struct sock *sk);
+extern void inet_unhash(struct sock *sk);
+
+extern struct sock *__inet_lookup_listener(struct net *net,
+ struct inet_hashinfo *hashinfo,
+ const __be32 daddr,
+ const unsigned short hnum,
+ const int dif);
+
+static inline struct sock *inet_lookup_listener(struct net *net,
+ struct inet_hashinfo *hashinfo,
+ __be32 daddr, __be16 dport, int dif)
+{
+ return __inet_lookup_listener(net, hashinfo, daddr, ntohs(dport), dif);
+}
+
+/* Socket demux engine toys. */
+/* What happens here is ugly; there's a pair of adjacent fields in
+ struct inet_sock; __be16 dport followed by __u16 num. We want to
+ search by pair, so we combine the keys into a single 32bit value
+ and compare with 32bit value read from &...->dport. Let's at least
+ make sure that it's not mixed with anything else...
+ On 64bit targets we combine comparisons with pair of adjacent __be32
+ fields in the same way.
+*/
+typedef __u32 __bitwise __portpair;
+#ifdef __BIG_ENDIAN
+#define INET_COMBINED_PORTS(__sport, __dport) \
+ ((__force __portpair)(((__force __u32)(__be16)(__sport) << 16) | (__u32)(__dport)))
+#else /* __LITTLE_ENDIAN */
+#define INET_COMBINED_PORTS(__sport, __dport) \
+ ((__force __portpair)(((__u32)(__dport) << 16) | (__force __u32)(__be16)(__sport)))
+#endif
+
+#if (BITS_PER_LONG == 64)
+typedef __u64 __bitwise __addrpair;
+#ifdef __BIG_ENDIAN
+#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
+ const __addrpair __name = (__force __addrpair) ( \
+ (((__force __u64)(__be32)(__saddr)) << 32) | \
+ ((__force __u64)(__be32)(__daddr)));
+#else /* __LITTLE_ENDIAN */
+#define INET_ADDR_COOKIE(__name, __saddr, __daddr) \
+ const __addrpair __name = (__force __addrpair) ( \
+ (((__force __u64)(__be32)(__daddr)) << 32) | \
+ ((__force __u64)(__be32)(__saddr)));
+#endif /* __BIG_ENDIAN */
+#define INET_MATCH(__sk, __net, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
+ (((__sk)->sk_hash == (__hash)) && net_eq(sock_net(__sk), (__net)) && \
+ ((*((__addrpair *)&(inet_sk(__sk)->daddr))) == (__cookie)) && \
+ ((*((__portpair *)&(inet_sk(__sk)->dport))) == (__ports)) && \
+ (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
+#define INET_TW_MATCH(__sk, __net, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
+ (((__sk)->sk_hash == (__hash)) && net_eq(sock_net(__sk), (__net)) && \
+ ((*((__addrpair *)&(inet_twsk(__sk)->tw_daddr))) == (__cookie)) && \
+ ((*((__portpair *)&(inet_twsk(__sk)->tw_dport))) == (__ports)) && \
+ (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
+#else /* 32-bit arch */
+#define INET_ADDR_COOKIE(__name, __saddr, __daddr)
+#define INET_MATCH(__sk, __net, __hash, __cookie, __saddr, __daddr, __ports, __dif) \
+ (((__sk)->sk_hash == (__hash)) && net_eq(sock_net(__sk), (__net)) && \
+ (inet_sk(__sk)->daddr == (__saddr)) && \
+ (inet_sk(__sk)->rcv_saddr == (__daddr)) && \
+ ((*((__portpair *)&(inet_sk(__sk)->dport))) == (__ports)) && \
+ (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
+#define INET_TW_MATCH(__sk, __net, __hash,__cookie, __saddr, __daddr, __ports, __dif) \
+ (((__sk)->sk_hash == (__hash)) && net_eq(sock_net(__sk), (__net)) && \
+ (inet_twsk(__sk)->tw_daddr == (__saddr)) && \
+ (inet_twsk(__sk)->tw_rcv_saddr == (__daddr)) && \
+ ((*((__portpair *)&(inet_twsk(__sk)->tw_dport))) == (__ports)) && \
+ (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
+#endif /* 64-bit arch */
+
+/*
+ * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so we need
+ * not check it for lookups anymore, thanks Alexey. -DaveM
+ *
+ * Local BH must be disabled here.
+ */
+extern struct sock * __inet_lookup_established(struct net *net,
+ struct inet_hashinfo *hashinfo,
+ const __be32 saddr, const __be16 sport,
+ const __be32 daddr, const u16 hnum, const int dif);
+
+static inline struct sock *
+ inet_lookup_established(struct net *net, struct inet_hashinfo *hashinfo,
+ const __be32 saddr, const __be16 sport,
+ const __be32 daddr, const __be16 dport,
+ const int dif)
+{
+ return __inet_lookup_established(net, hashinfo, saddr, sport, daddr,
+ ntohs(dport), dif);
+}
+
+static inline struct sock *__inet_lookup(struct net *net,
+ struct inet_hashinfo *hashinfo,
+ const __be32 saddr, const __be16 sport,
+ const __be32 daddr, const __be16 dport,
+ const int dif)
+{
+ u16 hnum = ntohs(dport);
+ struct sock *sk = __inet_lookup_established(net, hashinfo,
+ saddr, sport, daddr, hnum, dif);
+
+ return sk ? : __inet_lookup_listener(net, hashinfo, daddr, hnum, dif);
+}
+
+static inline struct sock *inet_lookup(struct net *net,
+ struct inet_hashinfo *hashinfo,
+ const __be32 saddr, const __be16 sport,
+ const __be32 daddr, const __be16 dport,
+ const int dif)
+{
+ struct sock *sk;
+
+ local_bh_disable();
+ sk = __inet_lookup(net, hashinfo, saddr, sport, daddr, dport, dif);
+ local_bh_enable();
+
+ return sk;
+}
+
+static inline struct sock *__inet_lookup_skb(struct inet_hashinfo *hashinfo,
+ struct sk_buff *skb,
+ const __be16 sport,
+ const __be16 dport)
+{
+ struct sock *sk;
+ const struct iphdr *iph = ip_hdr(skb);
+
+ if (unlikely(sk = skb_steal_sock(skb)))
+ return sk;
+ else
+ return __inet_lookup(dev_net(skb->dst->dev), hashinfo,
+ iph->saddr, sport,
+ iph->daddr, dport, inet_iif(skb));
+}
+
+extern int __inet_hash_connect(struct inet_timewait_death_row *death_row,
+ struct sock *sk, u32 port_offset,
+ int (*check_established)(struct inet_timewait_death_row *,
+ struct sock *, __u16, struct inet_timewait_sock **),
+ void (*hash)(struct sock *sk));
+extern int inet_hash_connect(struct inet_timewait_death_row *death_row,
+ struct sock *sk);
+#endif /* _INET_HASHTABLES_H */