Merge commit 'v2.6.32' into reiserfs/kill-bkl

Merge-reason: The tree was based 2.6.31. It's better to be up to date
with 2.6.32. Although no conflicting changes were made in between,
it gives benchmarking results closer to the lastest kernel behaviour.

1 files changed, 154 insertions, 14 deletions

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 33b59bd92c4..cf538ed5ef6 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -288,9 +288,7 @@ try_again:
 		err = ulen;
 
 out_free:
-	lock_sock(sk);
-	skb_free_datagram(sk, skb);
-	release_sock(sk);
+	skb_free_datagram_locked(sk, skb);
 out:
 	return err;
 
@@ -638,6 +636,47 @@ static void udp_v6_flush_pending_frames(struct sock *sk)
 	}
 }
 
+/**
+ * 	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
+ * 	@sk: 	socket we are sending on
+ * 	@skb: 	sk_buff containing the filled-in UDP header
+ * 	        (checksum field must be zeroed out)
+ */
+static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb,
+				 const struct in6_addr *saddr,
+				 const struct in6_addr *daddr, int len)
+{
+	unsigned int offset;
+	struct udphdr *uh = udp_hdr(skb);
+	__wsum csum = 0;
+
+	if (skb_queue_len(&sk->sk_write_queue) == 1) {
+		/* Only one fragment on the socket.  */
+		skb->csum_start = skb_transport_header(skb) - skb->head;
+		skb->csum_offset = offsetof(struct udphdr, check);
+		uh->check = ~csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, 0);
+	} else {
+		/*
+		 * HW-checksum won't work as there are two or more
+		 * fragments on the socket so that all csums of sk_buffs
+		 * should be together
+		 */
+		offset = skb_transport_offset(skb);
+		skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
+
+		skb->ip_summed = CHECKSUM_NONE;
+
+		skb_queue_walk(&sk->sk_write_queue, skb) {
+			csum = csum_add(csum, skb->csum);
+		}
+
+		uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP,
+					    csum);
+		if (uh->check == 0)
+			uh->check = CSUM_MANGLED_0;
+	}
+}
+
 /*
  *	Sending
  */
@@ -668,7 +707,11 @@ static int udp_v6_push_pending_frames(struct sock *sk)
 
 	if (is_udplite)
 		csum = udplite_csum_outgoing(sk, skb);
-	 else
+	else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
+		udp6_hwcsum_outgoing(sk, skb, &fl->fl6_src, &fl->fl6_dst,
+				     up->len);
+		goto send;
+	} else
 		csum = udp_csum_outgoing(sk, skb);
 
 	/* add protocol-dependent pseudo-header */
@@ -677,13 +720,20 @@ static int udp_v6_push_pending_frames(struct sock *sk)
 	if (uh->check == 0)
 		uh->check = CSUM_MANGLED_0;
 
+send:
 	err = ip6_push_pending_frames(sk);
+	if (err) {
+		if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
+			UDP6_INC_STATS_USER(sock_net(sk),
+					    UDP_MIB_SNDBUFERRORS, is_udplite);
+			err = 0;
+		}
+	} else
+		UDP6_INC_STATS_USER(sock_net(sk),
+				    UDP_MIB_OUTDATAGRAMS, is_udplite);
 out:
 	up->len = 0;
 	up->pending = 0;
-	if (!err)
-		UDP6_INC_STATS_USER(sock_net(sk),
-				UDP_MIB_OUTDATAGRAMS, is_udplite);
 	return err;
 }
 
@@ -900,11 +950,8 @@ do_udp_sendmsg:
 			hlimit = ip6_dst_hoplimit(dst);
 	}
 
-	if (tclass < 0) {
+	if (tclass < 0)
 		tclass = np->tclass;
-		if (tclass < 0)
-			tclass = 0;
-	}
 
 	if (msg->msg_flags&MSG_CONFIRM)
 		goto do_confirm;
@@ -995,7 +1042,7 @@ void udpv6_destroy_sock(struct sock *sk)
  *	Socket option code for UDP
  */
 int udpv6_setsockopt(struct sock *sk, int level, int optname,
-		     char __user *optval, int optlen)
+		     char __user *optval, unsigned int optlen)
 {
 	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
 		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
@@ -1005,7 +1052,7 @@ int udpv6_setsockopt(struct sock *sk, int level, int optname,
 
 #ifdef CONFIG_COMPAT
 int compat_udpv6_setsockopt(struct sock *sk, int level, int optname,
-			    char __user *optval, int optlen)
+			    char __user *optval, unsigned int optlen)
 {
 	if (level == SOL_UDP  ||  level == SOL_UDPLITE)
 		return udp_lib_setsockopt(sk, level, optname, optval, optlen,
@@ -1032,9 +1079,102 @@ int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
 }
 #endif
 
-static struct inet6_protocol udpv6_protocol = {
+static int udp6_ufo_send_check(struct sk_buff *skb)
+{
+	struct ipv6hdr *ipv6h;
+	struct udphdr *uh;
+
+	if (!pskb_may_pull(skb, sizeof(*uh)))
+		return -EINVAL;
+
+	ipv6h = ipv6_hdr(skb);
+	uh = udp_hdr(skb);
+
+	uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
+				     IPPROTO_UDP, 0);
+	skb->csum_start = skb_transport_header(skb) - skb->head;
+	skb->csum_offset = offsetof(struct udphdr, check);
+	skb->ip_summed = CHECKSUM_PARTIAL;
+	return 0;
+}
+
+static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, int features)
+{
+	struct sk_buff *segs = ERR_PTR(-EINVAL);
+	unsigned int mss;
+	unsigned int unfrag_ip6hlen, unfrag_len;
+	struct frag_hdr *fptr;
+	u8 *mac_start, *prevhdr;
+	u8 nexthdr;
+	u8 frag_hdr_sz = sizeof(struct frag_hdr);
+	int offset;
+	__wsum csum;
+
+	mss = skb_shinfo(skb)->gso_size;
+	if (unlikely(skb->len <= mss))
+		goto out;
+
+	if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
+		/* Packet is from an untrusted source, reset gso_segs. */
+		int type = skb_shinfo(skb)->gso_type;
+
+		if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
+			     !(type & (SKB_GSO_UDP))))
+			goto out;
+
+		skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
+
+		segs = NULL;
+		goto out;
+	}
+
+	/* Do software UFO. Complete and fill in the UDP checksum as HW cannot
+	 * do checksum of UDP packets sent as multiple IP fragments.
+	 */
+	offset = skb->csum_start - skb_headroom(skb);
+	csum = skb_checksum(skb, offset, skb->len- offset, 0);
+	offset += skb->csum_offset;
+	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
+	skb->ip_summed = CHECKSUM_NONE;
+
+	/* Check if there is enough headroom to insert fragment header. */
+	if ((skb_headroom(skb) < frag_hdr_sz) &&
+	    pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
+		goto out;
+
+	/* Find the unfragmentable header and shift it left by frag_hdr_sz
+	 * bytes to insert fragment header.
+	 */
+	unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
+	nexthdr = *prevhdr;
+	*prevhdr = NEXTHDR_FRAGMENT;
+	unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
+		     unfrag_ip6hlen;
+	mac_start = skb_mac_header(skb);
+	memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
+
+	skb->mac_header -= frag_hdr_sz;
+	skb->network_header -= frag_hdr_sz;
+
+	fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
+	fptr->nexthdr = nexthdr;
+	fptr->reserved = 0;
+	ipv6_select_ident(fptr);
+
+	/* Fragment the skb. ipv6 header and the remaining fields of the
+	 * fragment header are updated in ipv6_gso_segment()
+	 */
+	segs = skb_segment(skb, features);
+
+out:
+	return segs;
+}
+
+static const struct inet6_protocol udpv6_protocol = {
 	.handler	=	udpv6_rcv,
 	.err_handler	=	udpv6_err,
+	.gso_send_check =	udp6_ufo_send_check,
+	.gso_segment	=	udp6_ufo_fragment,
 	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
 };