Commit 4b457bdf authored by Daniel Borkmann's avatar Daniel Borkmann Committed by David S. Miller
Browse files

packet: move hw/sw timestamp extraction into a small helper 



This patch introduces a small, internal helper function, that is used by
PF_PACKET. Based on the flags that are passed, it extracts the packet
timestamp in the receive path. This is merely a refactoring to remove
some duplicate code in tpacket_rcv(), to make it more readable, and to
enable others to use this function in PF_PACKET as well, e.g. for TX.

Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6e94d1ef

net/packet/af_packet.c

+23 −34
Original line number Diff line number Diff line
@@ -1657,6 +1657,26 @@ drop: 
	return 0;

}



static void tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,

				  unsigned int flags)

{

	struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);



	if (shhwtstamps) {

		if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&

		    ktime_to_timespec_cond(shhwtstamps->syststamp, ts))

			return;

		if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&

		    ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))

			return;

	}



	if (ktime_to_timespec_cond(skb->tstamp, ts))

		return;



	getnstimeofday(ts);

}



static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,

		       struct packet_type *pt, struct net_device *orig_dev)

{
@@ -1670,9 +1690,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 
	unsigned long status = TP_STATUS_USER;

	unsigned short macoff, netoff, hdrlen;

	struct sk_buff *copy_skb = NULL;

	struct timeval tv;

	struct timespec ts;

	struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);



	if (skb->pkt_type == PACKET_LOOPBACK)

		goto drop;
@@ -1755,6 +1773,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 
	spin_unlock(&sk->sk_receive_queue.lock);



	skb_copy_bits(skb, 0, h.raw + macoff, snaplen);

	tpacket_get_timestamp(skb, &ts, po->tp_tstamp);



	switch (po->tp_version) {

	case TPACKET_V1:
@@ -1762,18 +1781,8 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 
		h.h1->tp_snaplen = snaplen;

		h.h1->tp_mac = macoff;

		h.h1->tp_net = netoff;

		if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)

				&& shhwtstamps->syststamp.tv64)

			tv = ktime_to_timeval(shhwtstamps->syststamp);

		else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)

				&& shhwtstamps->hwtstamp.tv64)

			tv = ktime_to_timeval(shhwtstamps->hwtstamp);

		else if (skb->tstamp.tv64)

			tv = ktime_to_timeval(skb->tstamp);

		else

			do_gettimeofday(&tv);

		h.h1->tp_sec = tv.tv_sec;

		h.h1->tp_usec = tv.tv_usec;

		h.h1->tp_sec = ts.tv_sec;

		h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;

		hdrlen = sizeof(*h.h1);

		break;

	case TPACKET_V2:
@@ -1781,16 +1790,6 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 
		h.h2->tp_snaplen = snaplen;

		h.h2->tp_mac = macoff;

		h.h2->tp_net = netoff;

		if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)

				&& shhwtstamps->syststamp.tv64)

			ts = ktime_to_timespec(shhwtstamps->syststamp);

		else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)

				&& shhwtstamps->hwtstamp.tv64)

			ts = ktime_to_timespec(shhwtstamps->hwtstamp);

		else if (skb->tstamp.tv64)

			ts = ktime_to_timespec(skb->tstamp);

		else

			getnstimeofday(&ts);

		h.h2->tp_sec = ts.tv_sec;

		h.h2->tp_nsec = ts.tv_nsec;

		if (vlan_tx_tag_present(skb)) {
@@ -1811,16 +1810,6 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 
		h.h3->tp_snaplen = snaplen;

		h.h3->tp_mac = macoff;

		h.h3->tp_net = netoff;

		if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)

				&& shhwtstamps->syststamp.tv64)

			ts = ktime_to_timespec(shhwtstamps->syststamp);

		else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)

				&& shhwtstamps->hwtstamp.tv64)

			ts = ktime_to_timespec(shhwtstamps->hwtstamp);

		else if (skb->tstamp.tv64)

			ts = ktime_to_timespec(skb->tstamp);

		else

			getnstimeofday(&ts);

		h.h3->tp_sec  = ts.tv_sec;

		h.h3->tp_nsec = ts.tv_nsec;

		hdrlen = sizeof(*h.h3);

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