[PATCH net-next V2 04/11] tuntap: simplify error handling in tun_build_skb()
From: Jason Wang <hidden>
Date: 2018-09-12 03:17:02
Subsystem:
networking drivers, the rest, tun/tap driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Willem de Bruijn, Jason Wang
There's no need to duplicate page get logic in each action. So this patch tries to get page and calculate the offset before processing XDP actions (except for XDP_DROP), and undo them when meet errors (we don't care the performance on errors). This will be used for factoring out XDP logic. Signed-off-by: Jason Wang <redacted> --- drivers/net/tun.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 372caf7d67d9..257cf7342d54 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c@@ -1701,17 +1701,13 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, xdp_do_flush_map(); if (err) goto err_redirect; - rcu_read_unlock(); - local_bh_enable(); - return NULL; + goto out; case XDP_TX: get_page(alloc_frag->page); alloc_frag->offset += buflen; if (tun_xdp_tx(tun->dev, &xdp) < 0) goto err_redirect; - rcu_read_unlock(); - local_bh_enable(); - return NULL; + goto out; case XDP_PASS: delta = orig_data - xdp.data; len = xdp.data_end - xdp.data;
@@ -1742,7 +1738,7 @@ static struct sk_buff *tun_build_skb(struct tun_struct *tun, err_redirect: put_page(alloc_frag->page); -err_xdp: +out: rcu_read_unlock(); local_bh_enable(); this_cpu_inc(tun->pcpu_stats->rx_dropped);
--
2.17.1