ip: support for TX timestamps on UDP and RAW sockets

Instructions for time stamping outgoing packets are take from the
socket layer and later copied into the new skb.

Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

7 files changed, 19 insertions, 0 deletions

diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt
index a681a65b5bc7..0e58b4539176 100644
--- a/Documentation/networking/timestamping.txt
+++ b/Documentation/networking/timestamping.txt
@@ -56,6 +56,8 @@ and including the link layer, the scm_timestamping control message and
 a sock_extended_err control message with ee_errno==ENOMSG and
 ee_origin==SO_EE_ORIGIN_TIMESTAMPING. A socket with such a pending
 bounced packet is ready for reading as far as select() is concerned.
+If the outgoing packet has to be fragmented, then only the first
+fragment is time stamped and returned to the sending socket.
 
 All three values correspond to the same event in time, but were
 generated in different ways. Each of these values may be empty (= all
diff --git a/include/net/ip.h b/include/net/ip.h
index 10868139e656..4ac7577f98d0 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -55,6 +55,7 @@ struct ipcm_cookie
         __be32                  addr;
         int                     oif;
         struct ip_options       *opt;
+        union skb_shared_tx     shtx;
 };
 
 #define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))
diff --git a/net/can/raw.c b/net/can/raw.c
index 0703cba4bf9f..6aa154e806ae 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -648,6 +648,9 @@ static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
         err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
         if (err < 0)
                 goto free_skb;
+        err = sock_tx_timestamp(msg, sk, skb_tx(skb));
+        if (err < 0)
+                goto free_skb;
         skb->dev = dev;
         skb->sk  = sk;
 
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 705b33b184a3..382800a62b31 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -375,6 +375,7 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
         inet->tos = ip_hdr(skb)->tos;
         daddr = ipc.addr = rt->rt_src;
         ipc.opt = NULL;
+        ipc.shtx.flags = 0;
         if (icmp_param->replyopts.optlen) {
                 ipc.opt = &icmp_param->replyopts;
                 if (ipc.opt->srr)
@@ -532,6 +533,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
         inet_sk(sk)->tos = tos;
         ipc.addr = iph->saddr;
         ipc.opt = &icmp_param.replyopts;
+        ipc.shtx.flags = 0;
 
         {
                 struct flowi fl = {
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 8ebe86dd72af..3e7e910c7c0f 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -935,6 +935,10 @@ alloc_new_skb:
                                                            sk->sk_allocation);
                                 if (unlikely(skb == NULL))
                                         err = -ENOBUFS;
+                                else
+                                        /* only the initial fragment is
+                                           time stamped */
+                                        ipc->shtx.flags = 0;
                         }
                         if (skb == NULL)
                                 goto error;
@@ -945,6 +949,7 @@ alloc_new_skb:
                         skb->ip_summed = csummode;
                         skb->csum = 0;
                         skb_reserve(skb, hh_len);
+                        *skb_tx(skb) = ipc->shtx;
 
                         /*
                          *      Find where to start putting bytes.
@@ -1364,6 +1369,7 @@ void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *ar
 
         daddr = ipc.addr = rt->rt_src;
         ipc.opt = NULL;
+        ipc.shtx.flags = 0;
 
         if (replyopts.opt.optlen) {
                 ipc.opt = &replyopts.opt;
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index dff8bc4e0fac..f774651f0a47 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -493,6 +493,7 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
         ipc.addr = inet->saddr;
         ipc.opt = NULL;
+        ipc.shtx.flags = 0;
         ipc.oif = sk->sk_bound_dev_if;
 
         if (msg->msg_controllen) {
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index c47c989cb1fb..4bd178a111d5 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -596,6 +596,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                 return -EOPNOTSUPP;
 
         ipc.opt = NULL;
+        ipc.shtx.flags = 0;
 
         if (up->pending) {
                 /*
@@ -643,6 +644,9 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
         ipc.addr = inet->saddr;
 
         ipc.oif = sk->sk_bound_dev_if;
+        err = sock_tx_timestamp(msg, sk, &ipc.shtx);
+        if (err)
+                return err;
         if (msg->msg_controllen) {
                 err = ip_cmsg_send(sock_net(sk), msg, &ipc);
                 if (err)