From d39d938c8228a4c5860138a53cf2b9ae4c4baec2 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Sat, 31 Jan 2015 10:40:16 -0500 Subject: [PATCH] ipv6: Introduce udpv6_send_skb() Now that we can individually construct IPv6 skbs to send, add a udpv6_send_skb() function to populate the udp header and send the skb. This allows udp_v6_push_pending_frames() to re-use this function as well as enables us to add lockless sendmsg() support. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller --- net/ipv6/udp.c | 67 +++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 40 insertions(+), 27 deletions(-) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index e41f017..67a3d70 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -990,9 +990,10 @@ static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, { unsigned int offset; struct udphdr *uh = udp_hdr(skb); + struct sk_buff *frags = skb_shinfo(skb)->frag_list; __wsum csum = 0; - if (skb_queue_len(&sk->sk_write_queue) == 1) { + if (!frags) { /* Only one fragment on the socket. */ skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct udphdr, check); @@ -1008,9 +1009,9 @@ static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, skb->ip_summed = CHECKSUM_NONE; - skb_queue_walk(&sk->sk_write_queue, skb) { - csum = csum_add(csum, skb->csum); - } + do { + csum = csum_add(csum, frags->csum); + } while ((frags = frags->next)); uh->check = csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, csum); @@ -1023,26 +1024,15 @@ static void udp6_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, * Sending */ -static int udp_v6_push_pending_frames(struct sock *sk) +static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6) { - struct sk_buff *skb; + struct sock *sk = skb->sk; struct udphdr *uh; - struct udp_sock *up = udp_sk(sk); - struct inet_sock *inet = inet_sk(sk); - struct flowi6 *fl6; int err = 0; int is_udplite = IS_UDPLITE(sk); __wsum csum = 0; - - if (up->pending == AF_INET) - return udp_push_pending_frames(sk); - - fl6 = &inet->cork.fl.u.ip6; - - /* Grab the skbuff where UDP header space exists. */ - skb = skb_peek(&sk->sk_write_queue); - if (skb == NULL) - goto out; + int offset = skb_transport_offset(skb); + int len = skb->len - offset; /* * Create a UDP header @@ -1050,29 +1040,28 @@ static int udp_v6_push_pending_frames(struct sock *sk) uh = udp_hdr(skb); uh->source = fl6->fl6_sport; uh->dest = fl6->fl6_dport; - uh->len = htons(up->len); + uh->len = htons(len); uh->check = 0; if (is_udplite) - csum = udplite_csum_outgoing(sk, skb); - else if (up->no_check6_tx) { /* UDP csum disabled */ + csum = udplite_csum(skb); + else if (udp_sk(sk)->no_check6_tx) { /* UDP csum disabled */ skb->ip_summed = CHECKSUM_NONE; goto send; } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ - udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, - up->len); + udp6_hwcsum_outgoing(sk, skb, &fl6->saddr, &fl6->daddr, len); goto send; } else - csum = udp_csum_outgoing(sk, skb); + csum = udp_csum(skb); /* add protocol-dependent pseudo-header */ uh->check = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, - up->len, fl6->flowi6_proto, csum); + len, fl6->flowi6_proto, csum); if (uh->check == 0) uh->check = CSUM_MANGLED_0; send: - err = ip6_push_pending_frames(sk); + err = ip6_send_skb(skb); if (err) { if (err == -ENOBUFS && !inet6_sk(sk)->recverr) { UDP6_INC_STATS_USER(sock_net(sk), @@ -1082,6 +1071,30 @@ send: } else UDP6_INC_STATS_USER(sock_net(sk), UDP_MIB_OUTDATAGRAMS, is_udplite); + return err; +} + +static int udp_v6_push_pending_frames(struct sock *sk) +{ + struct sk_buff *skb; + struct udp_sock *up = udp_sk(sk); + struct flowi6 fl6; + int err = 0; + + if (up->pending == AF_INET) + return udp_push_pending_frames(sk); + + /* ip6_finish_skb will release the cork, so make a copy of + * fl6 here. + */ + fl6 = inet_sk(sk)->cork.fl.u.ip6; + + skb = ip6_finish_skb(sk); + if (!skb) + goto out; + + err = udp_v6_send_skb(skb, &fl6); + out: up->len = 0; up->pending = 0; -- 2.7.4