Commit e4a2a304 authored by Jason Wang's avatar Jason Wang Committed by David S. Miller
Browse files

net: sock: introduce SOCK_XDP 



This patch introduces a new sock flag - SOCK_XDP. This will be used
for notifying the upper layer that XDP program is attached on the
lower socket, and requires for extra headroom.

TUN will be the first user.

Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9708d2b5

drivers/net/tun.c

+19 −0
Original line number Diff line number Diff line
@@ -869,6 +869,9 @@ static int tun_attach(struct tun_struct *tun, struct file *file, 
		tun_napi_init(tun, tfile, napi);

	}



	if (rtnl_dereference(tun->xdp_prog))

		sock_set_flag(&tfile->sk, SOCK_XDP);



	tun_set_real_num_queues(tun);



	/* device is allowed to go away first, so no need to hold extra
@@ -1241,13 +1244,29 @@ static int tun_xdp_set(struct net_device *dev, struct bpf_prog *prog, 
		       struct netlink_ext_ack *extack)

{

	struct tun_struct *tun = netdev_priv(dev);

	struct tun_file *tfile;

	struct bpf_prog *old_prog;

	int i;



	old_prog = rtnl_dereference(tun->xdp_prog);

	rcu_assign_pointer(tun->xdp_prog, prog);

	if (old_prog)

		bpf_prog_put(old_prog);



	for (i = 0; i < tun->numqueues; i++) {

		tfile = rtnl_dereference(tun->tfiles[i]);

		if (prog)

			sock_set_flag(&tfile->sk, SOCK_XDP);

		else

			sock_reset_flag(&tfile->sk, SOCK_XDP);

	}

	list_for_each_entry(tfile, &tun->disabled, next) {

		if (prog)

			sock_set_flag(&tfile->sk, SOCK_XDP);

		else

			sock_reset_flag(&tfile->sk, SOCK_XDP);

	}



	return 0;

}

include/net/sock.h

+1 −0
Original line number Diff line number Diff line
@@ -800,6 +800,7 @@ enum sock_flags { 
	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */

	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */

	SOCK_TXTIME,

	SOCK_XDP, /* XDP is attached */

};



#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))

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