[DECNET]: Tidy send side socket SKB allocation.
Patch from Steve Whitehouse which I've vetted and tested:
"This patch is really intended has a move towards fixing the
sendmsg/recvmsg functions in various ways so that we will finally
have working nagle. Also reduces code duplication."
Signed-off-by: Patrick Caulfield <patrick@tykepenguin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index 621680f..348f36b 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -1876,8 +1876,27 @@
return mss_now;
}
+/*
+ * N.B. We get the timeout wrong here, but then we always did get it
+ * wrong before and this is another step along the road to correcting
+ * it. It ought to get updated each time we pass through the routine,
+ * but in practise it probably doesn't matter too much for now.
+ */
+static inline struct sk_buff *dn_alloc_send_pskb(struct sock *sk,
+ unsigned long datalen, int noblock,
+ int *errcode)
+{
+ struct sk_buff *skb = sock_alloc_send_skb(sk, datalen,
+ noblock, errcode);
+ if (skb) {
+ skb->protocol = __constant_htons(ETH_P_DNA_RT);
+ skb->pkt_type = PACKET_OUTGOING;
+ }
+ return skb;
+}
+
static int dn_sendmsg(struct kiocb *iocb, struct socket *sock,
- struct msghdr *msg, size_t size)
+ struct msghdr *msg, size_t size)
{
struct sock *sk = sock->sk;
struct dn_scp *scp = DN_SK(sk);
@@ -1892,7 +1911,7 @@
struct dn_skb_cb *cb;
size_t len;
unsigned char fctype;
- long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
+ long timeo;
if (flags & ~(MSG_TRYHARD|MSG_OOB|MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL|MSG_MORE|MSG_CMSG_COMPAT))
return -EOPNOTSUPP;
@@ -1900,18 +1919,21 @@
if (addr_len && (addr_len != sizeof(struct sockaddr_dn)))
return -EINVAL;
+ lock_sock(sk);
+ timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
/*
* The only difference between stream sockets and sequenced packet
* sockets is that the stream sockets always behave as if MSG_EOR
* has been set.
*/
if (sock->type == SOCK_STREAM) {
- if (flags & MSG_EOR)
- return -EINVAL;
+ if (flags & MSG_EOR) {
+ err = -EINVAL;
+ goto out;
+ }
flags |= MSG_EOR;
}
- lock_sock(sk);
err = dn_check_state(sk, addr, addr_len, &timeo, flags);
if (err)
@@ -1980,8 +2002,12 @@
/*
* Get a suitably sized skb.
+ * 64 is a bit of a hack really, but its larger than any
+ * link-layer headers and has served us well as a good
+ * guess as to their real length.
*/
- skb = dn_alloc_send_skb(sk, &len, flags & MSG_DONTWAIT, timeo, &err);
+ skb = dn_alloc_send_pskb(sk, len + 64 + DN_MAX_NSP_DATA_HEADER,
+ flags & MSG_DONTWAIT, &err);
if (err)
break;
@@ -1991,7 +2017,7 @@
cb = DN_SKB_CB(skb);
- skb_reserve(skb, DN_MAX_NSP_DATA_HEADER);
+ skb_reserve(skb, 64 + DN_MAX_NSP_DATA_HEADER);
if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
err = -EFAULT;
diff --git a/net/decnet/dn_nsp_out.c b/net/decnet/dn_nsp_out.c
index e0bebf4..53633d3 100644
--- a/net/decnet/dn_nsp_out.c
+++ b/net/decnet/dn_nsp_out.c
@@ -137,69 +137,6 @@
}
/*
- * Wrapper for the above, for allocs of data skbs. We try and get the
- * whole size thats been asked for (plus 11 bytes of header). If this
- * fails, then we try for any size over 16 bytes for SOCK_STREAMS.
- */
-struct sk_buff *dn_alloc_send_skb(struct sock *sk, size_t *size, int noblock, long timeo, int *err)
-{
- int space;
- int len;
- struct sk_buff *skb = NULL;
-
- *err = 0;
-
- while(skb == NULL) {
- if (signal_pending(current)) {
- *err = sock_intr_errno(timeo);
- break;
- }
-
- if (sk->sk_shutdown & SEND_SHUTDOWN) {
- *err = EINVAL;
- break;
- }
-
- if (sk->sk_err)
- break;
-
- len = *size + 11;
- space = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
-
- if (space < len) {
- if ((sk->sk_socket->type == SOCK_STREAM) &&
- (space >= (16 + 11)))
- len = space;
- }
-
- if (space < len) {
- set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
- if (noblock) {
- *err = EWOULDBLOCK;
- break;
- }
-
- clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
- SOCK_SLEEP_PRE(sk)
-
- if ((sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc)) <
- len)
- schedule();
-
- SOCK_SLEEP_POST(sk)
- continue;
- }
-
- if ((skb = dn_alloc_skb(sk, len, sk->sk_allocation)) == NULL)
- continue;
-
- *size = len - 11;
- }
-
- return skb;
-}
-
-/*
* Calculate persist timer based upon the smoothed round
* trip time and the variance. Backoff according to the
* nsp_backoff[] array.