Re: [PATCH 08/10] tun: Re-uanble UFO support.
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: 2014-12-17 22:33:40
Also in:
virtualization
subs: re-enable On Wed, Dec 17, 2014 at 01:20:53PM -0500, Vladislav Yasevich wrote:
Now that UFO is split into v4 and v6 parts, we can bring back v4 support without any trouble. Continue to handle legacy applications by selecting the IPv6 fragment id but do not change the gso type. Thist
s/Thist/this/
makes sure that two legacy VMs may still communicate.
This means IPv6 skbs with UFO (not UFO6) flag set are present in the stack. If possible, I think it would be better to make GSO type correct: UFO6, and then convert to UFO when copying to guest. A similar approach should be possible for OVS?
quoted hunk ↗ jump to hunk
Based on original work from Ben Hutchings. Fixes: 88e0e0e5aa7a ("drivers/net: Disable UFO through virtio") CC: Ben Hutchings <redacted> Signed-off-by: Vladislav Yasevich <redacted> --- drivers/net/tun.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-)diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 9dd3746..8c32fca 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c@@ -175,7 +175,7 @@ struct tun_struct { struct net_device *dev; netdev_features_t set_features; #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \ - NETIF_F_TSO6) + NETIF_F_TSO6|NETIF_F_UFO) int vnet_hdr_sz; int sndbuf;@@ -1152,20 +1152,15 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; break; case VIRTIO_NET_HDR_GSO_UDP: - { - static bool warned; - - if (!warned) { - warned = true; - netdev_warn(tun->dev, - "%s: using disabled UFO feature; please fix this program\n", - current->comm); - } skb_shinfo(skb)->gso_type = SKB_GSO_UDP; - if (skb->protocol == htons(ETH_P_IPV6)) + if (vlan_get_protocol(skb) == htons(ETH_P_IPV6)) { + /* This allows legacy application to work. + * Do not change the gso_type as it may + * not be upderstood by legacy applications.
Shouldn't we handle legacy applications when passing packets to userspace?
quoted hunk ↗ jump to hunk
+ */ ipv6_proxy_select_ident(skb); + } break; - } default: tun->dev->stats.rx_frame_errors++; kfree_skb(skb);@@ -1273,6 +1268,8 @@ static ssize_t tun_put_user(struct tun_struct *tun, gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; else if (sinfo->gso_type & SKB_GSO_TCPV6) gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; + else if (sinfo->gso_type & SKB_GSO_UDP) + gso.gso_type = VIRTIO_NET_HDR_GSO_UDP; else { pr_err("unexpected GSO type: " "0x%x, gso_size %d, hdr_len %d\n",@@ -1780,6 +1777,11 @@ static int set_offload(struct tun_struct *tun, unsigned long arg) features |= NETIF_F_TSO6; arg &= ~(TUN_F_TSO4|TUN_F_TSO6); } + + if (arg & TUN_F_UFO) { + features |= NETIF_F_UFO; + arg &= ~TUN_F_UFO; + } } /* This gives the user a way to test for new features in future by-- 1.9.3