Commit 51a0d5e5 authored by Marc Kleine-Budde's avatar Marc Kleine-Budde
Browse files

can: raw: add support for SO_TXTIME/SCM_TXTIME 

This patch calls into sock_cmsg_send() to parse the user supplied
control information into a struct sockcm_cookie. Then assign the
requested transmit time to the skb.

This makes it possible to use the Earliest TXTIME First (ETF) packet
scheduler with the CAN_RAW protocol. The user can send a CAN_RAW frame
with a TXTIME and the kernel (with the ETF scheduler) will take care
of sending it to the network interface.

Link: https://lore.kernel.org/all/20220502091946.1916211-3-mkl@pengutronix.de


Acked-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 2af84932

net/can/raw.c

+10 −1
Original line number Diff line number Diff line
@@ -772,6 +772,7 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 
{

	struct sock *sk = sock->sk;

	struct raw_sock *ro = raw_sk(sk);

	struct sockcm_cookie sockc;

	struct sk_buff *skb;

	struct net_device *dev;

	int ifindex;
@@ -817,10 +818,18 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 
	if (err < 0)

		goto free_skb;



	skb_setup_tx_timestamp(skb, sk->sk_tsflags);

	sockcm_init(&sockc, sk);

	if (msg->msg_controllen) {

		err = sock_cmsg_send(sk, msg, &sockc);

		if (unlikely(err))

			goto free_skb;

	}



	skb->dev = dev;

	skb->priority = sk->sk_priority;

	skb->tstamp = sockc.transmit_time;



	skb_setup_tx_timestamp(skb, sockc.tsflags);



	err = can_send(skb, ro->loopback);