[NET]: Introduce inet_connection_sock

This creates struct inet_connection_sock, moving members out of struct
tcp_sock that are shareable with other INET connection oriented
protocols, such as DCCP, that in my private tree already uses most of
these members.

The functions that operate on these members were renamed, using a
inet_csk_ prefix while not being moved yet to a new file, so as to
ease the review of these changes.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 86 insertions, 0 deletions

diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
new file mode 100644
index 000000000000..ef609396e41b
--- /dev/null
+++ b/include/net/inet_connection_sock.h
@@ -0,0 +1,86 @@
+/*
+ * NET          Generic infrastructure for INET connection oriented protocols.
+ *
+ *              Definitions for inet_connection_sock 
+ *
+ * Authors:     Many people, see the TCP sources
+ *
+ *              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_CONNECTION_SOCK_H
+#define _INET_CONNECTION_SOCK_H
+
+#include <linux/ip.h>
+#include <linux/timer.h>
+#include <net/request_sock.h>
+
+struct inet_bind_bucket;
+struct inet_hashinfo;
+
+/** inet_connection_sock - INET connection oriented sock
+ *
+ * @icsk_accept_queue:     FIFO of established children 
+ * @icsk_bind_hash:        Bind node
+ * @icsk_timeout:          Timeout
+ * @icsk_retransmit_timer: Resend (no ack)
+ * @icsk_rto:              Retransmit timeout
+ * @icsk_retransmits:      Number of unrecovered [RTO] timeouts
+ * @icsk_pending:          Scheduled timer event
+ * @icsk_backoff:          Backoff
+ * @icsk_syn_retries:      Number of allowed SYN (or equivalent) retries
+ * @icsk_ack:              Delayed ACK control data
+ */
+struct inet_connection_sock {
+        /* inet_sock has to be the first member! */
+        struct inet_sock          icsk_inet;
+        struct request_sock_queue icsk_accept_queue;
+        struct inet_bind_bucket   *icsk_bind_hash;
+        unsigned long             icsk_timeout;
+        struct timer_list         icsk_retransmit_timer;
+        struct timer_list         icsk_delack_timer;
+        __u32                     icsk_rto;
+        __u8                      icsk_retransmits;
+        __u8                      icsk_pending;
+        __u8                      icsk_backoff;
+        __u8                      icsk_syn_retries;
+        struct {
+                __u8              pending;       /* ACK is pending                         */
+                __u8              quick;         /* Scheduled number of quick acks         */
+                __u8              pingpong;      /* The session is interactive             */
+                __u8              blocked;       /* Delayed ACK was blocked by socket lock */
+                __u32             ato;           /* Predicted tick of soft clock           */
+                unsigned long     timeout;       /* Currently scheduled timeout            */
+                __u32             lrcvtime;      /* timestamp of last received data packet */
+                __u16             last_seg_size; /* Size of last incoming segment          */
+                __u16             rcv_mss;       /* MSS used for delayed ACK decisions     */ 
+        } icsk_ack;
+};
+
+static inline struct inet_connection_sock *inet_csk(const struct sock *sk)
+{
+        return (struct inet_connection_sock *)sk;
+}
+
+extern void inet_csk_init_xmit_timers(struct sock *sk,
+                                      void (*retransmit_handler)(unsigned long),
+                                      void (*delack_handler)(unsigned long),
+                                      void (*keepalive_handler)(unsigned long));
+extern void inet_csk_clear_xmit_timers(struct sock *sk);
+
+extern struct request_sock *inet_csk_search_req(const struct sock *sk,
+                                                struct request_sock ***prevp,
+                                                const __u16 rport,
+                                                const __u32 raddr,
+                                                const __u32 laddr);
+extern int inet_csk_get_port(struct inet_hashinfo *hashinfo,
+                             struct sock *sk, unsigned short snum);
+
+extern struct dst_entry* inet_csk_route_req(struct sock *sk,
+                                            const struct request_sock *req);
+
+#endif /* _INET_CONNECTION_SOCK_H */