[PATCH net-next 0/4] net: remove clear_sk() method

[PATCH net-next 0/4] net: remove clear_sk() method

[Eric Dumazet]

Since IPv6 socket lookups no longer dereference pinet6 pointer
and UDP lost SLAB_DESTROY_BY_RCU special rules, we no longer
need special clear_sk() methods.

Eric Dumazet (4):
  ipv6: udp: remove udp_v6_clear_sk()
  udp: get rid of sk_prot_clear_portaddr_nulls()
  ipv6: tcp: get rid of tcp_v6_clear_sk()
  net: remove clear_sk() method

 include/net/sock.h  |  3 ---
 net/core/sock.c     | 26 ++------------------------
 net/ipv4/udp.c      |  1 -
 net/ipv4/udplite.c  |  1 -
 net/ipv6/tcp_ipv6.c | 12 ------------
 net/ipv6/udp.c      | 12 ------------
 net/ipv6/udp_impl.h |  2 --
 net/ipv6/udplite.c  |  1 -
 8 files changed, 2 insertions(+), 56 deletions(-)

-- 
2.8.0.rc3.226.g39d4020

[PATCH net-next 1/4] ipv6: udp: remove udp_v6_clear_sk()

[Eric Dumazet]

Now RCU lookups of ipv6 udp sockets no longer dereference
pinet6 field, we can get rid of udp_v6_clear_sk() helper.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv6/udp.c      | 13 +------------
 net/ipv6/udp_impl.h |  2 --
 net/ipv6/udplite.c  |  2 +-
 3 files changed, 2 insertions(+), 15 deletions(-)

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 81e2f98b958d..c86b9417f44e 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1424,17 +1424,6 @@ void udp6_proc_exit(struct net *net)
 }
 #endif /* CONFIG_PROC_FS */
 
-void udp_v6_clear_sk(struct sock *sk, int size)
-{
-	struct inet_sock *inet = inet_sk(sk);
-
-	/* we do not want to clear pinet6 field, because of RCU lookups */
-	sk_prot_clear_portaddr_nulls(sk, offsetof(struct inet_sock, pinet6));
-
-	size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
-	memset(&inet->pinet6 + 1, 0, size);
-}
-
 /* ------------------------------------------------------------------------ */
 
 struct proto udpv6_prot = {
@@ -1466,7 +1455,7 @@ struct proto udpv6_prot = {
 	.compat_setsockopt = compat_udpv6_setsockopt,
 	.compat_getsockopt = compat_udpv6_getsockopt,
 #endif
-	.clear_sk	   = udp_v6_clear_sk,
+	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 
 static struct inet_protosw udpv6_protosw = {
diff --git a/net/ipv6/udp_impl.h b/net/ipv6/udp_impl.h
index 0682c031ccdc..f6eb1ab34f4b 100644
--- a/net/ipv6/udp_impl.h
+++ b/net/ipv6/udp_impl.h
@@ -29,8 +29,6 @@ int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
 int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
 void udpv6_destroy_sock(struct sock *sk);
 
-void udp_v6_clear_sk(struct sock *sk, int size);
-
 #ifdef CONFIG_PROC_FS
 int udp6_seq_show(struct seq_file *seq, void *v);
 #endif
diff --git a/net/ipv6/udplite.c b/net/ipv6/udplite.c
index 9cf097e206e9..118057a5b759 100644
--- a/net/ipv6/udplite.c
+++ b/net/ipv6/udplite.c
@@ -56,7 +56,7 @@ struct proto udplitev6_prot = {
 	.compat_setsockopt = compat_udpv6_setsockopt,
 	.compat_getsockopt = compat_udpv6_getsockopt,
 #endif
-	.clear_sk	   = udp_v6_clear_sk,
+	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 
 static struct inet_protosw udplite6_protosw = {
-- 
2.8.0.rc3.226.g39d4020

[PATCH net-next 2/4] udp: get rid of sk_prot_clear_portaddr_nulls()

[Eric Dumazet]

Since we no longer use SLAB_DESTROY_BY_RCU for UDP,
we do not need sk_prot_clear_portaddr_nulls() helper.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/sock.h |  2 --
 net/core/sock.c    | 18 ------------------
 net/ipv4/udp.c     |  1 -
 net/ipv4/udplite.c |  1 -
 net/ipv6/udp.c     |  1 -
 net/ipv6/udplite.c |  1 -
 6 files changed, 24 deletions(-)

diff --git a/include/net/sock.h b/include/net/sock.h
index 2aab9b63bf16..1bc57609f8e1 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1242,8 +1242,6 @@ static inline int __sk_prot_rehash(struct sock *sk)
 	return sk->sk_prot->hash(sk);
 }
 
-void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
-
 /* About 10 seconds */
 #define SOCK_DESTROY_TIME (10*HZ)
 
diff --git a/net/core/sock.c b/net/core/sock.c
index 25dab8b60223..2b09c2967e21 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1315,24 +1315,6 @@ static void sock_copy(struct sock *nsk, const struct sock *osk)
 #endif
 }
 
-void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
-{
-	unsigned long nulls1, nulls2;
-
-	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
-	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
-	if (nulls1 > nulls2)
-		swap(nulls1, nulls2);
-
-	if (nulls1 != 0)
-		memset((char *)sk, 0, nulls1);
-	memset((char *)sk + nulls1 + sizeof(void *), 0,
-	       nulls2 - nulls1 - sizeof(void *));
-	memset((char *)sk + nulls2 + sizeof(void *), 0,
-	       size - nulls2 - sizeof(void *));
-}
-EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
-
 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
 		int family)
 {
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 8f5f7f6026f7..5c5807612cc0 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -2223,7 +2223,6 @@ struct proto udp_prot = {
 	.compat_setsockopt = compat_udp_setsockopt,
 	.compat_getsockopt = compat_udp_getsockopt,
 #endif
-	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 EXPORT_SYMBOL(udp_prot);
 
diff --git a/net/ipv4/udplite.c b/net/ipv4/udplite.c
index 3b3efbda48e1..67fc9d96e67d 100644
--- a/net/ipv4/udplite.c
+++ b/net/ipv4/udplite.c
@@ -61,7 +61,6 @@ struct proto 	udplite_prot = {
 	.compat_setsockopt = compat_udp_setsockopt,
 	.compat_getsockopt = compat_udp_getsockopt,
 #endif
-	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 EXPORT_SYMBOL(udplite_prot);
 
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index c86b9417f44e..9f0b025cc750 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1455,7 +1455,6 @@ struct proto udpv6_prot = {
 	.compat_setsockopt = compat_udpv6_setsockopt,
 	.compat_getsockopt = compat_udpv6_getsockopt,
 #endif
-	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 
 static struct inet_protosw udpv6_protosw = {
diff --git a/net/ipv6/udplite.c b/net/ipv6/udplite.c
index 118057a5b759..5cf0099b86f7 100644
--- a/net/ipv6/udplite.c
+++ b/net/ipv6/udplite.c
@@ -56,7 +56,6 @@ struct proto udplitev6_prot = {
 	.compat_setsockopt = compat_udpv6_setsockopt,
 	.compat_getsockopt = compat_udpv6_getsockopt,
 #endif
-	.clear_sk	   = sk_prot_clear_portaddr_nulls,
 };
 
 static struct inet_protosw udplite6_protosw = {
-- 
2.8.0.rc3.226.g39d4020

[PATCH net-next 3/4] ipv6: tcp: get rid of tcp_v6_clear_sk()

[Eric Dumazet]

Now RCU lookups of IPv6 TCP sockets no longer dereference pinet6,
we do not need tcp_v6_clear_sk() anymore.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv6/tcp_ipv6.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 33df8b8575cc..e0f46439e391 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1862,17 +1862,6 @@ void tcp6_proc_exit(struct net *net)
 }
 #endif
 
-static void tcp_v6_clear_sk(struct sock *sk, int size)
-{
-	struct inet_sock *inet = inet_sk(sk);
-
-	/* we do not want to clear pinet6 field, because of RCU lookups */
-	sk_prot_clear_nulls(sk, offsetof(struct inet_sock, pinet6));
-
-	size -= offsetof(struct inet_sock, pinet6) + sizeof(inet->pinet6);
-	memset(&inet->pinet6 + 1, 0, size);
-}
-
 struct proto tcpv6_prot = {
 	.name			= "TCPv6",
 	.owner			= THIS_MODULE,
@@ -1914,7 +1903,6 @@ struct proto tcpv6_prot = {
 	.compat_setsockopt	= compat_tcp_setsockopt,
 	.compat_getsockopt	= compat_tcp_getsockopt,
 #endif
-	.clear_sk		= tcp_v6_clear_sk,
 	.diag_destroy		= tcp_abort,
 };
 
-- 
2.8.0.rc3.226.g39d4020

[PATCH net-next 4/4] net: remove clear_sk() method

[Eric Dumazet]

We no longer use this handler, we can delete it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/sock.h | 1 -
 net/core/sock.c    | 8 ++------
 2 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/include/net/sock.h b/include/net/sock.h
index 1bc57609f8e1..c797c57f4d9f 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1020,7 +1020,6 @@ struct proto {
 	void			(*unhash)(struct sock *sk);
 	void			(*rehash)(struct sock *sk);
 	int			(*get_port)(struct sock *sk, unsigned short snum);
-	void			(*clear_sk)(struct sock *sk, int size);
 
 	/* Keeping track of sockets in use */
 #ifdef CONFIG_PROC_FS
diff --git a/net/core/sock.c b/net/core/sock.c
index 2b09c2967e21..51a730485649 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1326,12 +1326,8 @@ static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
 		if (!sk)
 			return sk;
-		if (priority & __GFP_ZERO) {
-			if (prot->clear_sk)
-				prot->clear_sk(sk, prot->obj_size);
-			else
-				sk_prot_clear_nulls(sk, prot->obj_size);
-		}
+		if (priority & __GFP_ZERO)
+			sk_prot_clear_nulls(sk, prot->obj_size);
 	} else
 		sk = kmalloc(prot->obj_size, priority);
 
-- 
2.8.0.rc3.226.g39d4020

Re: [PATCH net-next 0/4] net: remove clear_sk() method

[David Miller]

From: Eric Dumazet <edumazet@google.com>
Date: Tue, 23 Aug 2016 11:39:25 -0700

> Since IPv6 socket lookups no longer dereference pinet6 pointer
> and UDP lost SLAB_DESTROY_BY_RCU special rules, we no longer
> need special clear_sk() methods.

Series applied, thanks Eric.

There were some merge conflicts because I applied David Ahern's
sock diag udp patches first.

Please double check my work.

Thanks.

Re: [PATCH net-next 0/4] net: remove clear_sk() method

[Eric Dumazet]

On Tue, 2016-08-23 at 23:37 -0700, David Miller wrote:
> From: Eric Dumazet <edumazet@google.com>
> Date: Tue, 23 Aug 2016 11:39:25 -0700
> 
> > Since IPv6 socket lookups no longer dereference pinet6 pointer
> > and UDP lost SLAB_DESTROY_BY_RCU special rules, we no longer
> > need special clear_sk() methods.
> 
> Series applied, thanks Eric.
> 
> There were some merge conflicts because I applied David Ahern's
> sock diag udp patches first.
> 
> Please double check my work.

Sure, this all looks fine to me, thanks David !