Subject: [PATCH 3/12][DECNET] Don't use sk_protinfo + private sock slab cache

From: Arnaldo Carvalho de Melo <[email-masked]>
Date: Fri, 21 Jan 2005 01:19:03 -0200

Hi David/Patrick,

	Please see the log in the patch.

Best Regards,

- Arnaldo

===================================================================

[email-masked], 2005-01-20 20:36:07-02:00, [email-masked]
  [DECNET] Don't use sk_protinfo + private sock slab cache
  
  DecNET already uses a private sock slab cache, but initializes sk->sk_protinfo,
  pointing to (sk + 1), this is wrong because at sk_free time we call
  sk->sk_destruct, that by default points to sock_def_destruct, that does a kfree
  on sk->sk_protinfo, since it was initialized at net_proto_family->create() time
  (dn_create), but in decnet sk_protinfo was not kmalloced, it was allocated
  piggybacked to struct sock.
  
  This doesn't causes problems because decnet sets sk->sk_destruct to a custom
  function that doesn't calls kfree(sk->sk_protinfo), but to reach a long time
  goal of killing sk_protinfo lets just make DN_SK return sk + 1.
  
  I left merging dn_scp with dn_sock for later, as the current state suits my
  needs to introduce connection_sock.
  
  Signed-off-by: Arnaldo Carvalho de Melo <[email-masked]>
  Signed-off-by: David S. Miller <[email-masked]>

 include/net/dn.h       |    6 +++++-
 net/decnet/af_decnet.c |    3 +--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff -Nru a/include/net/dn.h b/include/net/dn.h
--- a/include/net/dn.h	2005-01-21 00:23:40 -02:00
+++ b/include/net/dn.h	2005-01-21 00:23:40 -02:00
@@ -2,6 +2,7 @@
 #define _NET_DN_H
 
 #include <linux/dn.h>
+#include <net/sock.h>
 #include <asm/byteorder.h>
 
 typedef unsigned short dn_address;
@@ -133,7 +134,10 @@
 
 };
 
-#define DN_SK(__sk) ((struct dn_scp *)(__sk)->sk_protinfo)
+static inline struct dn_scp *DN_SK(struct sock *sk)
+{
+	return (struct dn_scp *)(sk + 1);
+}
 
 /*
  * src,dst : Source and Destination DECnet addresses
diff -Nru a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
--- a/net/decnet/af_decnet.c	2005-01-21 00:23:40 -02:00
+++ b/net/decnet/af_decnet.c	2005-01-21 00:23:40 -02:00
@@ -456,8 +456,6 @@
 	if  (!sk)
 		goto out;
 
-	sk->sk_protinfo = scp = (struct dn_scp *)(sk + 1);
-
 	if (sock)
 		sock->ops = &dn_proto_ops;
 	sock_init_data(sock, sk);
@@ -471,6 +469,7 @@
 	sk->sk_allocation  = gfp;
 
 	/* Initialization of DECnet Session Control Port		*/
+	scp = DN_SK(sk);
 	scp->state	= DN_O;		/* Open			*/
 	scp->numdat	= 1;		/* Next data seg to tx	*/
 	scp->numoth	= 1;		/* Next oth data to tx  */