From: Jason Wang <jasowang@redhat.com>
Date: Wed, 12 Sep 2018 11:16:59 +0800
Subject: net: sock: introduce SOCK_XDP
Patch-mainline: v4.20-rc1
Git-commit: e4a2a3048ed93f0c354ad837f1d45fc8d389d538
References: bsc#1109837
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: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/tun.c | 19 +++++++++++++++++++
include/net/sock.h | 1 +
2 files changed, 20 insertions(+)
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -869,6 +869,9 @@ static int tun_attach(struct tun_struct
tun_napi_init(tun, tfile, napi, napi_frags);
}
+ 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
@@ -1204,13 +1207,29 @@ static int tun_xdp_set(struct net_device
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;
}
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -782,6 +782,7 @@ enum sock_flags {
SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
+ SOCK_XDP, /* XDP is attached */
};
#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))