1 #ifndef _VIRTIO_NET_H_
2 # define _VIRTIO_NET_H_
3 
4 /* The feature bitmap for virtio net */
5 #define VIRTIO_NET_F_CSUM       0       /* Host handles pkts w/ partial csum */
6 #define VIRTIO_NET_F_GUEST_CSUM 1       /* Guest handles pkts w/ partial csum */
7 #define VIRTIO_NET_F_MAC        5       /* Host has given MAC address. */
8 #define VIRTIO_NET_F_GSO        6       /* Host handles pkts w/ any GSO type */
9 #define VIRTIO_NET_F_GUEST_TSO4 7       /* Guest can handle TSOv4 in. */
10 #define VIRTIO_NET_F_GUEST_TSO6 8       /* Guest can handle TSOv6 in. */
11 #define VIRTIO_NET_F_GUEST_ECN  9       /* Guest can handle TSO[6] w/ ECN in. */
12 #define VIRTIO_NET_F_GUEST_UFO  10      /* Guest can handle UFO in. */
13 #define VIRTIO_NET_F_HOST_TSO4  11      /* Host can handle TSOv4 in. */
14 #define VIRTIO_NET_F_HOST_TSO6  12      /* Host can handle TSOv6 in. */
15 #define VIRTIO_NET_F_HOST_ECN   13      /* Host can handle TSO[6] w/ ECN in. */
16 #define VIRTIO_NET_F_HOST_UFO   14      /* Host can handle UFO in. */
17 
18 struct virtio_net_config
19 {
20    /* The config defining mac address (if VIRTIO_NET_F_MAC) */
21    u8 mac[6];
22 } __attribute__((packed));
23 
24 /* This is the first element of the scatter-gather list.  If you don't
25  * specify GSO or CSUM features, you can simply ignore the header. */
26 
27 struct virtio_net_hdr
28 {
29 #define VIRTIO_NET_HDR_F_NEEDS_CSUM     1       // Use csum_start, csum_offset
30    uint8_t flags;
31 #define VIRTIO_NET_HDR_GSO_NONE         0       // Not a GSO frame
32 #define VIRTIO_NET_HDR_GSO_TCPV4        1       // GSO frame, IPv4 TCP (TSO)
33 /* FIXME: Do we need this?  If they said they can handle ECN, do they care? */
34 #define VIRTIO_NET_HDR_GSO_TCPV4_ECN    2       // GSO frame, IPv4 TCP w/ ECN
35 #define VIRTIO_NET_HDR_GSO_UDP          3       // GSO frame, IPv4 UDP (UFO)
36 #define VIRTIO_NET_HDR_GSO_TCPV6        4       // GSO frame, IPv6 TCP
37 #define VIRTIO_NET_HDR_GSO_ECN          0x80    // TCP has ECN set
38    uint8_t gso_type;
39    uint16_t hdr_len;
40    uint16_t gso_size;
41    uint16_t csum_start;
42    uint16_t csum_offset;
43 };
44 #endif /* _VIRTIO_NET_H_ */
45