From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: [PATCH net-next] tuntap: hardware vlan tx support Date: Tue, 23 Jul 2013 15:15:48 +0800 Message-ID: <1374563748-38821-1-git-send-email-jasowang@redhat.com> Cc: Jason Wang , Basil Gor To: davem@davemloft.net, mst@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Inspired by commit f09e2249c4f5c7c13261ec73f5a7807076af0c8e (macvtap: restore vlan header on user read). This patch adds hardware vlan tx support for tuntap. This is done by copying vlan header directly into userspace in tun_put_user() instead of doing it through __vlan_put_tag() in dev_hard_start_xmit(). This eliminates one unnecessary memove in vlan_insert_tag() for 802.1ad and 802.1q traffic. pktgen test shows about 20% improvement for 802.1q traffic: Before: 662149pps 317Mb/sec (317831520bps) errors: 0 After: 801033pps 384Mb/sec (384495840bps) errors: 0 Cc: Basil Gor Cc: Michael S. Tsirkin Signed-off-by: Jason Wang --- drivers/net/tun.c | 39 +++++++++++++++++++++++++++++++++++---- 1 files changed, 35 insertions(+), 4 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index a72d141..66e265d 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -60,6 +60,7 @@ #include #include #include +#include #include #include #include @@ -1265,6 +1266,7 @@ static ssize_t tun_put_user(struct tun_struct *tun, { struct tun_pi pi = { 0, skb->protocol }; ssize_t total = 0; + int vlan_offset = 0; if (!(tun->flags & TUN_NO_PI)) { if ((len -= sizeof(pi)) < 0) @@ -1328,11 +1330,39 @@ static ssize_t tun_put_user(struct tun_struct *tun, total += tun->vnet_hdr_sz; } - len = min_t(int, skb->len, len); + if (!vlan_tx_tag_present(skb)) + len = min_t(int, skb->len, len); + else { + int copy, ret; + struct { + __be16 h_vlan_proto; + __be16 h_vlan_TCI; + } veth; + veth.h_vlan_proto = skb->vlan_proto; + veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb)); + + vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); + len = min_t(int, skb->len + VLAN_HLEN, len); + + copy = min_t(int, vlan_offset, len); + ret = skb_copy_datagram_const_iovec(skb, 0, iv, total, copy); + len -= copy; + total += copy; + if (ret || !len) + goto done; + + copy = min_t(int, sizeof(veth), len); + ret = memcpy_toiovecend(iv, (void *)&veth, total, copy); + len -= copy; + total += copy; + if (ret || !len) + goto done; + } - skb_copy_datagram_const_iovec(skb, 0, iv, total, len); - total += skb->len; + skb_copy_datagram_const_iovec(skb, vlan_offset, iv, total, len); + total += len; +done: tun->dev->stats.tx_packets++; tun->dev->stats.tx_bytes += len; @@ -1691,7 +1721,8 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) tun_flow_init(tun); dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | - TUN_USER_FEATURES; + TUN_USER_FEATURES | NETIF_F_HW_VLAN_CTAG_TX | + NETIF_F_HW_VLAN_STAG_TX; dev->features = dev->hw_features; dev->vlan_features = dev->features; -- 1.7.1