kernel-ark/include/linux/virtio_net.h
Rusty Russell 34a48579e4 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 <rusty@rustcorp.com.au>
2008-02-04 23:50:02 +11:00

37 lines
1.3 KiB
C

#ifndef _LINUX_VIRTIO_NET_H
#define _LINUX_VIRTIO_NET_H
#include <linux/virtio_config.h>
/* The ID for virtio_net */
#define VIRTIO_ID_NET 1
/* The feature bitmap for virtio net */
#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
{
/* The config defining mac address (if VIRTIO_NET_F_MAC) */
__u8 mac[6];
} __attribute__((packed));
/* This is the first element of the scatter-gather list. If you don't
* specify GSO or CSUM features, you can simply ignore the header. */
struct virtio_net_hdr
{
#define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 // Use csum_start, csum_offset
__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)
#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 */
__u16 csum_start; /* Position to start checksumming from */
__u16 csum_offset; /* Offset after that to place checksum */
};
#endif /* _LINUX_VIRTIO_NET_H */