From 34a48579e4fb380604d06f0409db3851bd22d785 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 4 Feb 2008 23:50:02 -0500 Subject: [PATCH] virtio: Tweak virtio_net defines 1) Turn GSO on virtio net into an all-or-nothing (keep checksumming separate). Having multiple bits is a pain: if you can't support something you should handle it in software, which is still a performance win. 2) Make VIRTIO_NET_HDR_GSO_ECN a flag in the header, so it can apply to IPv6 or v4. 3) Rename VIRTIO_NET_F_NO_CSUM to VIRTIO_NET_F_CSUM (ie. means we do checksumming). 4) Add csum and gso params to virtio_net to allow more testing. Signed-off-by: Rusty Russell --- drivers/net/virtio_net.c | 32 ++++++++++++++++---------------- include/linux/virtio_net.h | 12 ++++-------- 2 files changed, 20 insertions(+), 24 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 3492ae0951de..73f01db59ab9 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -24,6 +24,10 @@ #include #include +static int csum = 1, gso = 1; +module_param(csum, bool, 0444); +module_param(gso, bool, 0444); + /* FIXME: MTU in config. */ #define MAX_PACKET_LEN (ETH_HLEN+ETH_DATA_LEN) @@ -88,13 +92,10 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb, if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) { pr_debug("GSO!\n"); - switch (hdr->gso_type) { + switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { case VIRTIO_NET_HDR_GSO_TCPV4: skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; break; - case VIRTIO_NET_HDR_GSO_TCPV4_ECN: - skb_shinfo(skb)->gso_type = SKB_GSO_TCP_ECN; - break; case VIRTIO_NET_HDR_GSO_UDP: skb_shinfo(skb)->gso_type = SKB_GSO_UDP; break; @@ -108,6 +109,9 @@ static void receive_skb(struct net_device *dev, struct sk_buff *skb, goto frame_err; } + if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN) + skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; + skb_shinfo(skb)->gso_size = hdr->gso_size; if (skb_shinfo(skb)->gso_size == 0) { if (net_ratelimit()) @@ -244,9 +248,7 @@ static int start_xmit(struct sk_buff *skb, struct net_device *dev) if (skb_is_gso(skb)) { hdr->hdr_len = skb_transport_header(skb) - skb->data; hdr->gso_size = skb_shinfo(skb)->gso_size; - if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN) - hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4_ECN; - else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) + if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; @@ -254,6 +256,8 @@ static int start_xmit(struct sk_buff *skb, struct net_device *dev) hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP; else BUG(); + if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN) + hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; } else { hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE; hdr->gso_size = hdr->hdr_len = 0; @@ -330,17 +334,13 @@ static int virtnet_probe(struct virtio_device *vdev) SET_NETDEV_DEV(dev, &vdev->dev); /* Do we support "hardware" checksums? */ - if (vdev->config->feature(vdev, VIRTIO_NET_F_NO_CSUM)) { + if (csum && vdev->config->feature(vdev, VIRTIO_NET_F_CSUM)) { /* This opens up the world of extra features. */ dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; - if (vdev->config->feature(vdev, VIRTIO_NET_F_TSO4)) - dev->features |= NETIF_F_TSO; - if (vdev->config->feature(vdev, VIRTIO_NET_F_UFO)) - dev->features |= NETIF_F_UFO; - if (vdev->config->feature(vdev, VIRTIO_NET_F_TSO4_ECN)) - dev->features |= NETIF_F_TSO_ECN; - if (vdev->config->feature(vdev, VIRTIO_NET_F_TSO6)) - dev->features |= NETIF_F_TSO6; + if (gso && vdev->config->feature(vdev, VIRTIO_NET_F_GSO)) { + dev->features |= NETIF_F_TSO | NETIF_F_UFO + | NETIF_F_TSO_ECN | NETIF_F_TSO6; + } } /* Configuration may specify what MAC to use. Otherwise random. */ diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index 1456f7b936d0..1ea3351df609 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -6,12 +6,9 @@ #define VIRTIO_ID_NET 1 /* The feature bitmap for virtio net */ -#define VIRTIO_NET_F_NO_CSUM 0 -#define VIRTIO_NET_F_TSO4 1 -#define VIRTIO_NET_F_UFO 2 -#define VIRTIO_NET_F_TSO4_ECN 3 -#define VIRTIO_NET_F_TSO6 4 -#define VIRTIO_NET_F_MAC 5 +#define VIRTIO_NET_F_CSUM 0 /* Can handle pkts w/ partial csum */ +#define VIRTIO_NET_F_MAC 5 /* Host has given MAC address. */ +#define VIRTIO_NET_F_GSO 6 /* Can handle pkts w/ any GSO type */ struct virtio_net_config { @@ -27,10 +24,9 @@ struct virtio_net_hdr __u8 flags; #define VIRTIO_NET_HDR_GSO_NONE 0 // Not a GSO frame #define VIRTIO_NET_HDR_GSO_TCPV4 1 // GSO frame, IPv4 TCP (TSO) -/* FIXME: Do we need this? If they said they can handle ECN, do they care? */ -#define VIRTIO_NET_HDR_GSO_TCPV4_ECN 2 // GSO frame, IPv4 TCP w/ ECN #define VIRTIO_NET_HDR_GSO_UDP 3 // GSO frame, IPv4 UDP (UFO) #define VIRTIO_NET_HDR_GSO_TCPV6 4 // GSO frame, IPv6 TCP +#define VIRTIO_NET_HDR_GSO_ECN 0x80 // TCP has ECN set __u8 gso_type; __u16 hdr_len; /* Ethernet + IP + tcp/udp hdrs */ __u16 gso_size; /* Bytes to append to gso_hdr_len per frame */ -- 2.39.2