[NET] first bits of net/core/stream.c

Move tcp sk_wmem_queued related functions to net/core/stream.c, will be
used by other SOCK_STREAM protocols, starting with LLC.

Also move the tcp_charge_skb to sock.h, for the same reasons.
Signed-off-by: Arnaldo Carvalho de Melo <acme@conectiva.com.br>

include/net/sock.h

@@ -413,6 +413,21 @@ static inline int sk_acceptq_is_full(struct sock *sk)
 	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
 }
 
+/*
+ * Compute minimal free write space needed to queue new packets.
+ */
+static inline int sk_stream_min_wspace(struct sock *sk)
+{
+	return sk->sk_wmem_queued / 2;
+}
+
+static inline int sk_stream_wspace(struct sock *sk)
+{
+	return sk->sk_sndbuf - sk->sk_wmem_queued;
+}
+
+extern void sk_stream_write_space(struct sock *sk);
+
 /* The per-socket spinlock must be held here. */
 #define sk_add_backlog(__sk, __skb)				\
 do {	if (!(__sk)->sk_backlog.tail) {				\
@@ -902,6 +917,11 @@ sk_dst_check(struct sock *sk, u32 cookie)
 	return dst;
 }
 
+static inline void sk_charge_skb(struct sock *sk, struct sk_buff *skb)
+{
+	sk->sk_wmem_queued   += skb->truesize;
+	sk->sk_forward_alloc -= skb->truesize;
+}
 
 /*
  * 	Queue a received datagram if it will fit. Stream and sequenced

include/net/tcp.h

@@ -870,7 +870,6 @@ extern void			tcp_close(struct sock *sk,
 					  long timeout);
 extern struct sock *		tcp_accept(struct sock *sk, int flags, int *err);
 extern unsigned int		tcp_poll(struct file * file, struct socket *sock, struct poll_table_struct *wait);
-extern void			tcp_write_space(struct sock *sk); 
 
 extern int			tcp_getsockopt(struct sock *sk, int level, 
 					       int optname,
@@ -1195,21 +1194,6 @@ struct tcp_skb_cb {
 
 #include <net/tcp_ecn.h>
 
-
-/*
- *	Compute minimal free write space needed to queue new packets. 
- */
-static inline int tcp_min_write_space(struct sock *sk)
-{
-	return sk->sk_wmem_queued / 2;
-}
- 
-static inline int tcp_wspace(struct sock *sk)
-{
-	return sk->sk_sndbuf - sk->sk_wmem_queued;
-}
-
-
 /* This determines how many packets are "in the network" to the best
  * of our knowledge.  In many cases it is conservative, but where
  * detailed information is available from the receiver (via SACK
@@ -1899,12 +1883,6 @@ static inline void tcp_free_skb(struct sock *sk, struct sk_buff *skb)
 	__kfree_skb(skb);
 }
 
-static inline void tcp_charge_skb(struct sock *sk, struct sk_buff *skb)
-{
-	sk->sk_wmem_queued += skb->truesize;
-	sk->sk_forward_alloc -= skb->truesize;
-}
-
 extern void __tcp_mem_reclaim(struct sock *sk);
 extern int tcp_mem_schedule(struct sock *sk, int size, int kind);
 

net/core/Makefile

@@ -2,7 +2,7 @@
 # Makefile for the Linux networking core.
 #
 
-obj-y := sock.o skbuff.o iovec.o datagram.o scm.o
+obj-y := sock.o skbuff.o iovec.o datagram.o stream.o scm.o
 
 obj-$(CONFIG_SYSCTL) += sysctl_net_core.o
 

net/core/stream.c

+/*
+ *     SUCS NET3:
+ *
+ *     Generic stream handling routines. These are generic for most
+ *     protocols. Even IP. Tonight 8-).
+ *     This is used because TCP, LLC (others too) layer all have mostly
+ *     identical sendmsg() and recvmsg() code.
+ *     So we (will) share it here.
+ *
+ *     Authors:        Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *                     (from old tcp.c code)
+ *                     Alan Cox <alan@redhat.com> (Borrowed comments 8-))
+ */
+
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/signal.h>
+#include <linux/wait.h>
+#include <net/sock.h>
+
+/**
+ * sk_stream_write_space - stream socket write_space callback.
+ * sk - socket
+ *
+ * FIXME: write proper description
+ */
+void sk_stream_write_space(struct sock *sk)
+{
+	struct socket *sock = sk->sk_socket;
+
+	if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && sock) {
+		clear_bit(SOCK_NOSPACE, &sock->flags);
+
+		if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
+			wake_up_interruptible(sk->sk_sleep);
+		if (sock->fasync_list && !(sk->sk_shutdown & SEND_SHUTDOWN))
+			sock_wake_async(sock, 2, POLL_OUT);
+	}
+}
+
+EXPORT_SYMBOL(sk_stream_write_space);

net/ipv4/tcp.c

@@ -447,7 +447,7 @@ unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
 			mask |= POLLIN | POLLRDNORM;
 
 		if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
-			if (tcp_wspace(sk) >= tcp_min_write_space(sk)) {
+			if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)) {
 				mask |= POLLOUT | POLLWRNORM;
 			} else {  /* send SIGIO later */
 				set_bit(SOCK_ASYNC_NOSPACE,
@@ -458,7 +458,7 @@ unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
 				 * wspace test but before the flags are set,
 				 * IO signal will be lost.
 				 */
-				if (tcp_wspace(sk) >= tcp_min_write_space(sk))
+				if (sk_stream_wspace(sk) >= sk_stream_min_wspace(sk))
 					mask |= POLLOUT | POLLWRNORM;
 			}
 		}
@@ -469,24 +469,6 @@ unsigned int tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
 	return mask;
 }
 
-/*
- *	TCP socket write_space callback.
- */
-void tcp_write_space(struct sock *sk)
-{
-	struct socket *sock = sk->sk_socket;
-
-	if (tcp_wspace(sk) >= tcp_min_write_space(sk) && sock) {
-		clear_bit(SOCK_NOSPACE, &sock->flags);
-
-		if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
-			wake_up_interruptible(sk->sk_sleep);
-
-		if (sock->fasync_list && !(sk->sk_shutdown & SEND_SHUTDOWN))
-			sock_wake_async(sock, 2, POLL_OUT);
-	}
-}
-
 int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
 {
 	struct tcp_opt *tp = tcp_sk(sk);
@@ -796,7 +778,7 @@ static inline void skb_entail(struct sock *sk, struct tcp_opt *tp,
 	TCP_SKB_CB(skb)->flags = TCPCB_FLAG_ACK;
 	TCP_SKB_CB(skb)->sacked = 0;
 	__skb_queue_tail(&sk->sk_write_queue, skb);
-	tcp_charge_skb(sk, skb);
+	sk_charge_skb(sk, skb);
 	if (!tp->send_head)
 		tp->send_head = skb;
 	else if (tp->nonagle&TCP_NAGLE_PUSH)
@@ -2635,4 +2617,3 @@ EXPORT_SYMBOL(tcp_shutdown);
 EXPORT_SYMBOL(tcp_sockets_allocated);
 EXPORT_SYMBOL(tcp_statistics);
 EXPORT_SYMBOL(tcp_timewait_cachep);
-EXPORT_SYMBOL(tcp_write_space);

net/ipv4/tcp_ipv4.c

@@ -2081,7 +2081,7 @@ static int tcp_v4_init_sock(struct sock *sk)
 
 	sk->sk_state = TCP_CLOSE;
 
-	sk->sk_write_space = tcp_write_space;
+	sk->sk_write_space = sk_stream_write_space;
 	sk->sk_use_write_queue = 1;
 
 	tp->af_specific = &ipv4_specific;

net/ipv4/tcp_minisocks.c

@@ -720,7 +720,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct open_request *req,
 		newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
 		newsk->sk_callback_lock = RW_LOCK_UNLOCKED;
 		skb_queue_head_init(&newsk->sk_error_queue);
-		newsk->sk_write_space = tcp_write_space;
+		newsk->sk_write_space = sk_stream_write_space;
 
 		if ((filter = newsk->sk_filter) != NULL)
 			sk_filter_charge(newsk, filter);

net/ipv4/tcp_output.c

@@ -326,7 +326,7 @@ static void tcp_queue_skb(struct sock *sk, struct sk_buff *skb)
 	/* Advance write_seq and place onto the write_queue. */
 	tp->write_seq = TCP_SKB_CB(skb)->end_seq;
 	__skb_queue_tail(&sk->sk_write_queue, skb);
-	tcp_charge_skb(sk, skb);
+	sk_charge_skb(sk, skb);
 
 	/* Queue it, remembering where we must start sending. */
 	if (tp->send_head == NULL)
@@ -439,7 +439,7 @@ static int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len)
 	buff = tcp_alloc_skb(sk, nsize, GFP_ATOMIC);
 	if (buff == NULL)
 		return -ENOMEM; /* We'll just try again later. */
-	tcp_charge_skb(sk, buff);
+	sk_charge_skb(sk, buff);
 
 	/* Correct the sequence numbers. */
 	TCP_SKB_CB(buff)->seq = TCP_SKB_CB(skb)->seq + len;
@@ -1169,7 +1169,7 @@ int tcp_send_synack(struct sock *sk)
 			__skb_unlink(skb, &sk->sk_write_queue);
 			__skb_queue_head(&sk->sk_write_queue, nskb);
 			tcp_free_skb(sk, skb);
-			tcp_charge_skb(sk, nskb);
+			sk_charge_skb(sk, nskb);
 			skb = nskb;
 		}
 
@@ -1329,7 +1329,7 @@ int tcp_connect(struct sock *sk)
 	TCP_SKB_CB(buff)->when = tcp_time_stamp;
 	tp->retrans_stamp = TCP_SKB_CB(buff)->when;
 	__skb_queue_tail(&sk->sk_write_queue, buff);
-	tcp_charge_skb(sk, buff);
+	sk_charge_skb(sk, buff);
 	tp->packets_out++;
 	tcp_transmit_skb(sk, skb_clone(buff, GFP_KERNEL));
 	TCP_INC_STATS(TcpActiveOpens);

net/ipv6/tcp_ipv6.c

@@ -1879,7 +1879,7 @@ static int tcp_v6_init_sock(struct sock *sk)
 
 	tp->af_specific = &ipv6_specific;
 
-	sk->sk_write_space = tcp_write_space;
+	sk->sk_write_space = sk_stream_write_space;
 	sk->sk_use_write_queue = 1;
 
 	sk->sk_sndbuf = sysctl_tcp_wmem[1];

net/sunrpc/svcsock.c

@@ -125,7 +125,7 @@ svc_sock_wspace(struct svc_sock *svsk)
 	int wspace;
 
 	if (svsk->sk_sock->type == SOCK_STREAM)
-		wspace = tcp_wspace(svsk->sk_sk);
+		wspace = sk_stream_wspace(svsk->sk_sk);
 	else
 		wspace = sock_wspace(svsk->sk_sk);
 

net/sunrpc/xprt.c

@@ -1086,8 +1086,8 @@ xprt_write_space(struct sock *sk)
 
 	/* Wait until we have enough socket memory */
 	if (xprt->stream) {
-		/* from net/ipv4/tcp.c:tcp_write_space */
-		if (tcp_wspace(sk) < tcp_min_write_space(sk))
+		/* from net/core/stream.c:sk_stream_write_space */
+		if (sk_stream_wspace(sk) < sk_stream_min_wspace(sk))
 			goto out;
 	} else {
 		/* from net/core/sock.c:sock_def_write_space */