net: simplify flags for tx timestamping

This patch removes the abstraction introduced by the union skb_shared_tx in
the shared skb data.

The access of the different union elements at several places led to some
confusion about accessing the shared tx_flags e.g. in skb_orphan_try().

    http://marc.info/?l=linux-netdev&m=128084897415886&w=2

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

9 files changed, 20 insertions, 21 deletions

diff --git a/net/can/raw.c b/net/can/raw.c
index a10e3338f08..7d77e67e57a 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -647,12 +647,12 @@ 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));
+	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
 	if (err < 0)
 		goto free_skb;
 
 	/* to be able to check the received tx sock reference in raw_rcv() */
-	skb_tx(skb)->prevent_sk_orphan = 1;
+	skb_shinfo(skb)->tx_flags |= SKBTX_DRV_NEEDS_SK_REF;
 
 	skb->dev = dev;
 	skb->sk  = sk;
diff --git a/net/core/dev.c b/net/core/dev.c
index 586a11cb439..c1dc8a95f6f 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1902,14 +1902,14 @@ static int dev_gso_segment(struct sk_buff *skb)
 
 /*
  * Try to orphan skb early, right before transmission by the device.
- * We cannot orphan skb if tx timestamp is requested, since
- * drivers need to call skb_tstamp_tx() to send the timestamp.
+ * We cannot orphan skb if tx timestamp is requested or the sk-reference
+ * is needed on driver level for other reasons, e.g. see net/can/raw.c
  */
 static inline void skb_orphan_try(struct sk_buff *skb)
 {
 	struct sock *sk = skb->sk;
 
-	if (sk && !skb_tx(skb)->flags) {
+	if (sk && !skb_shinfo(skb)->tx_flags) {
 		/* skb_tx_hash() wont be able to get sk.
 		 * We copy sk_hash into skb->rxhash
 		 */
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 3a2513f0d0c..99ef721f773 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3016,7 +3016,7 @@ void skb_tstamp_tx(struct sk_buff *orig_skb,
 	} else {
 		/*
 		 * no hardware time stamps available,
-		 * so keep the skb_shared_tx and only
+		 * so keep the shared tx_flags and only
 		 * store software time stamp
 		 */
 		skb->tstamp = ktime_get_real();
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index a0d847c7cba..96bc7f9475a 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -379,7 +379,7 @@ 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;
+	ipc.tx_flags = 0;
 	if (icmp_param->replyopts.optlen) {
 		ipc.opt = &icmp_param->replyopts;
 		if (ipc.opt->srr)
@@ -538,7 +538,7 @@ 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;
+	ipc.tx_flags = 0;
 
 	{
 		struct flowi fl = {
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 04b69896df5..e807492f177 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -953,7 +953,7 @@ alloc_new_skb:
 				else
 					/* only the initial fragment is
 					   time stamped */
-					ipc->shtx.flags = 0;
+					ipc->tx_flags = 0;
 			}
 			if (skb == NULL)
 				goto error;
@@ -964,7 +964,7 @@ alloc_new_skb:
 			skb->ip_summed = csummode;
 			skb->csum = 0;
 			skb_reserve(skb, hh_len);
-			*skb_tx(skb) = ipc->shtx;
+			skb_shinfo(skb)->tx_flags = ipc->tx_flags;
 
 			/*
 			 *	Find where to start putting bytes.
@@ -1384,7 +1384,7 @@ 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;
+	ipc.tx_flags = 0;
 
 	if (replyopts.opt.optlen) {
 		ipc.opt = &replyopts.opt;
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 009a7b2aa1e..1f85ef28989 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -505,7 +505,7 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
 	ipc.addr = inet->inet_saddr;
 	ipc.opt = NULL;
-	ipc.shtx.flags = 0;
+	ipc.tx_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 32e0bef60d0..86e757e162e 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -797,7 +797,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		return -EOPNOTSUPP;
 
 	ipc.opt = NULL;
-	ipc.shtx.flags = 0;
+	ipc.tx_flags = 0;
 
 	if (up->pending) {
 		/*
@@ -845,7 +845,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	ipc.addr = inet->inet_saddr;
 
 	ipc.oif = sk->sk_bound_dev_if;
-	err = sock_tx_timestamp(msg, sk, &ipc.shtx);
+	err = sock_tx_timestamp(sk, &ipc.tx_flags);
 	if (err)
 		return err;
 	if (msg->msg_controllen) {
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 9a17f28b125..3616f27b9d4 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -488,7 +488,7 @@ retry:
 	skb->dev = dev;
 	skb->priority = sk->sk_priority;
 	skb->mark = sk->sk_mark;
-	err = sock_tx_timestamp(msg, sk, skb_tx(skb));
+	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
 	if (err < 0)
 		goto out_unlock;
 
@@ -1209,7 +1209,7 @@ static int packet_snd(struct socket *sock,
 	err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
 	if (err)
 		goto out_free;
-	err = sock_tx_timestamp(msg, sk, skb_tx(skb));
+	err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
 	if (err < 0)
 		goto out_free;
 
diff --git a/net/socket.c b/net/socket.c
index 2270b941bcc..7848d12f5e4 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -535,14 +535,13 @@ void sock_release(struct socket *sock)
 }
 EXPORT_SYMBOL(sock_release);
 
-int sock_tx_timestamp(struct msghdr *msg, struct sock *sk,
-		      union skb_shared_tx *shtx)
+int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags)
 {
-	shtx->flags = 0;
+	*tx_flags = 0;
 	if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
-		shtx->hardware = 1;
+		*tx_flags |= SKBTX_HW_TSTAMP;
 	if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
-		shtx->software = 1;
+		*tx_flags |= SKBTX_SW_TSTAMP;
 	return 0;
 }
 EXPORT_SYMBOL(sock_tx_timestamp);