* INET4 prototypes used by INET6
*/
+struct msghdr;
+struct sock;
+struct sockaddr;
+struct socket;
+
extern void inet_remove_sock(struct sock *sk1);
extern void inet_put_sock(unsigned short num,
struct sock *sk);
#ifndef _INET_HASHTABLES_H
#define _INET_HASHTABLES_H
+#include <linux/ip.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
#include <linux/types.h>
+/* This is for all connections with a full identity, no wildcards.
+ * New scheme, half the table is for TIME_WAIT, the other half is
+ * for the rest. I'll experiment with dynamic table growth later.
+ */
+struct inet_ehash_bucket {
+ rwlock_t lock;
+ struct hlist_head chain;
+} __attribute__((__aligned__(8)));
+
+/* 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 {
+ unsigned short port;
+ signed short fastreuse;
+ struct hlist_node node;
+ struct hlist_head owners;
+};
+
+#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;
+};
+
+/* 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
+ *
+ * First half of the table is for sockets not in TIME_WAIT, second half
+ * is for TIME_WAIT sockets only.
+ */
+ struct inet_ehash_bucket *ehash;
+
+ /* 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;
+
+ int bhash_size;
+ int ehash_size;
+
+ /* 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 hlist_head listening_hash[INET_LHTABLE_SIZE];
+
+ /* 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
+ * are often dirty.
+ */
+ rwlock_t lhash_lock ____cacheline_aligned;
+ atomic_t lhash_users;
+ wait_queue_head_t lhash_wait;
+ spinlock_t portalloc_lock;
+};
+
static inline int inet_ehashfn(const __u32 laddr, const __u16 lport,
const __u32 faddr, const __u16 fport,
const int ehash_size)
return inet_ehashfn(laddr, lport, faddr, fport, ehash_size);
}
+extern struct inet_bind_bucket *
+ inet_bind_bucket_create(kmem_cache_t *cachep,
+ struct inet_bind_hashbucket *head,
+ const unsigned short snum);
+extern void inet_bind_bucket_destroy(kmem_cache_t *cachep,
+ struct inet_bind_bucket *tb);
+
+static inline int inet_bhashfn(const __u16 lport, const int bhash_size)
+{
+ return lport & (bhash_size - 1);
+}
+
+/* These can have wildcards, don't try too hard. */
+static inline int inet_lhashfn(const unsigned short num)
+{
+ return num & (INET_LHTABLE_SIZE - 1);
+}
+
+static inline int inet_sk_listen_hashfn(const struct sock *sk)
+{
+ return inet_lhashfn(inet_sk(sk)->num);
+}
+
#endif /* _INET_HASHTABLES_H */
#include <linux/slab.h>
#include <linux/cache.h>
#include <linux/percpu.h>
+#include <net/inet_hashtables.h>
#include <net/checksum.h>
#include <net/request_sock.h>
#include <net/sock.h>
#endif
#include <linux/seq_file.h>
-/* This is for all connections with a full identity, no wildcards.
- * New scheme, half the table is for TIME_WAIT, the other half is
- * for the rest. I'll experiment with dynamic table growth later.
- */
-struct inet_ehash_bucket {
- rwlock_t lock;
- struct hlist_head chain;
-} __attribute__((__aligned__(8)));
-
-/* This is for listening sockets, thus all sockets which possess wildcards. */
-#define INET_LHTABLE_SIZE 32 /* Yes, really, this is all you need. */
-
-/* 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 {
- unsigned short port;
- signed short fastreuse;
- struct hlist_node node;
- struct hlist_head owners;
-};
-
-#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;
-};
-
-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
- *
- * First half of the table is for sockets not in TIME_WAIT, second half
- * is for TIME_WAIT sockets only.
- */
- struct inet_ehash_bucket *ehash;
-
- /* 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;
-
- int bhash_size;
- int ehash_size;
-
- /* 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 hlist_head listening_hash[INET_LHTABLE_SIZE];
-
- /* 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
- * are often dirty.
- */
- rwlock_t lhash_lock ____cacheline_aligned;
- atomic_t lhash_users;
- wait_queue_head_t lhash_wait;
- spinlock_t portalloc_lock;
-};
-
extern struct inet_hashinfo tcp_hashinfo;
#define tcp_ehash (tcp_hashinfo.ehash)
#define tcp_bhash (tcp_hashinfo.bhash)
#define tcp_portalloc_lock (tcp_hashinfo.portalloc_lock)
extern kmem_cache_t *tcp_bucket_cachep;
-extern struct inet_bind_bucket *
- inet_bind_bucket_create(kmem_cache_t *cachep,
- struct inet_bind_hashbucket *head,
- const unsigned short snum);
-extern void inet_bind_bucket_destroy(kmem_cache_t *cachep,
- struct inet_bind_bucket *tb);
-extern int tcp_port_rover;
-/* These are AF independent. */
-static inline int inet_bhashfn(const __u16 lport, const int bhash_size)
-{
- return lport & (bhash_size - 1);
-}
+extern int tcp_port_rover;
extern void tcp_bind_hash(struct sock *sk, struct inet_bind_bucket *tb,
unsigned short snum);
ipv6_addr_equal(&inet6_sk(__sk)->rcv_saddr, (__daddr)) && \
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
-/* These can have wildcards, don't try too hard. */
-static inline int inet_lhashfn(const unsigned short num)
-{
- return num & (INET_LHTABLE_SIZE - 1);
-}
-
-static inline int inet_sk_listen_hashfn(const struct sock *sk)
-{
- return inet_lhashfn(inet_sk(sk)->num);
-}
-
#define MAX_TCP_HEADER (128 + MAX_HEADER)
/*
obj-y := route.o inetpeer.o protocol.o \
ip_input.o ip_fragment.o ip_forward.o ip_options.o \
- ip_output.o ip_sockglue.o \
+ ip_output.o ip_sockglue.o inet_hashtables.o \
tcp.o tcp_input.o tcp_output.o tcp_timer.o tcp_ipv4.o \
tcp_minisocks.o tcp_cong.o \
datagram.o raw.o udp.o arp.o icmp.o devinet.o af_inet.o igmp.o \
--- /dev/null
+/*
+ * 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.
+ *
+ * Generic INET transport hashtables
+ *
+ * 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.
+ */
+
+#include <linux/config.h>
+#include <linux/slab.h>
+
+#include <net/inet_hashtables.h>
+
+/*
+ * Allocate and initialize a new local port bind bucket.
+ * The bindhash mutex for snum's hash chain must be held here.
+ */
+struct inet_bind_bucket *inet_bind_bucket_create(kmem_cache_t *cachep,
+ struct inet_bind_hashbucket *head,
+ const unsigned short snum)
+{
+ struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, SLAB_ATOMIC);
+
+ if (tb != NULL) {
+ tb->port = snum;
+ tb->fastreuse = 0;
+ INIT_HLIST_HEAD(&tb->owners);
+ hlist_add_head(&tb->node, &head->chain);
+ }
+ return tb;
+}
+
+EXPORT_SYMBOL(inet_bind_bucket_create);
+
+/*
+ * Caller must hold hashbucket lock for this tb with local BH disabled
+ */
+void inet_bind_bucket_destroy(kmem_cache_t *cachep, struct inet_bind_bucket *tb)
+{
+ if (hlist_empty(&tb->owners)) {
+ __hlist_del(&tb->node);
+ kmem_cache_free(cachep, tb);
+ }
+}
int sysctl_local_port_range[2] = { 1024, 4999 };
int tcp_port_rover = 1024 - 1;
-/* Allocate and initialize a new local port bind bucket.
- * The bindhash mutex for snum's hash chain must be held here.
- */
-struct inet_bind_bucket *inet_bind_bucket_create(kmem_cache_t *cachep,
- struct inet_bind_hashbucket *head,
- const unsigned short snum)
-{
- struct inet_bind_bucket *tb = kmem_cache_alloc(cachep, SLAB_ATOMIC);
- if (tb) {
- tb->port = snum;
- tb->fastreuse = 0;
- INIT_HLIST_HEAD(&tb->owners);
- hlist_add_head(&tb->node, &head->chain);
- }
- return tb;
-}
-
-/* Caller must hold hashbucket lock for this tb with local BH disabled */
-void inet_bind_bucket_destroy(kmem_cache_t *cachep, struct inet_bind_bucket *tb)
-{
- if (hlist_empty(&tb->owners)) {
- __hlist_del(&tb->node);
- kmem_cache_free(cachep, tb);
- }
-}
-
/* Caller must disable local BH processing. */
static __inline__ void __tcp_inherit_port(struct sock *sk, struct sock *child)
{