include/linux/virtio_net.h

   1 #ifndef _LINUX_VIRTIO_NET_H
   2 #define _LINUX_VIRTIO_NET_H
   3 /* This header is BSD licensed so anyone can use the definitions to implement
   4  * compatible drivers/servers. */
   5 #include <linux/virtio_config.h>
   6
   7 /* The ID for virtio_net */
   8 #define VIRTIO_ID_NET   1
   9
  10 /* The feature bitmap for virtio net */
  11 #define VIRTIO_NET_F_CSUM       0       /* Host handles pkts w/ partial csum */
  12 #define VIRTIO_NET_F_GUEST_CSUM 1       /* Guest handles pkts w/ partial csum */
  13 #define VIRTIO_NET_F_MAC        5       /* Host has given MAC address. */
  14 #define VIRTIO_NET_F_GSO        6       /* Host handles pkts w/ any GSO type */
  15 #define VIRTIO_NET_F_GUEST_TSO4 7       /* Guest can handle TSOv4 in. */
  16 #define VIRTIO_NET_F_GUEST_TSO6 8       /* Guest can handle TSOv6 in. */
  17 #define VIRTIO_NET_F_GUEST_ECN  9       /* Guest can handle TSO[6] w/ ECN in. */
  18 #define VIRTIO_NET_F_GUEST_UFO  10      /* Guest can handle UFO in. */
  19 #define VIRTIO_NET_F_HOST_TSO4  11      /* Host can handle TSOv4 in. */
  20 #define VIRTIO_NET_F_HOST_TSO6  12      /* Host can handle TSOv6 in. */
  21 #define VIRTIO_NET_F_HOST_ECN   13      /* Host can handle TSO[6] w/ ECN in. */
  22 #define VIRTIO_NET_F_HOST_UFO   14      /* Host can handle UFO in. */
  23 #define VIRTIO_NET_F_MRG_RXBUF  15      /* Host can merge receive buffers. */
  24
  25 struct virtio_net_config
  26 {
  27         /* The config defining mac address (if VIRTIO_NET_F_MAC) */
  28         __u8 mac[6];
  29 } __attribute__((packed));
  30
  31 /* This is the first element of the scatter-gather list.  If you don't
  32  * specify GSO or CSUM features, you can simply ignore the header. */
  33 struct virtio_net_hdr
  34 {
  35 #define VIRTIO_NET_HDR_F_NEEDS_CSUM     1       // Use csum_start, csum_offset
  36         __u8 flags;
  37 #define VIRTIO_NET_HDR_GSO_NONE         0       // Not a GSO frame
  38 #define VIRTIO_NET_HDR_GSO_TCPV4        1       // GSO frame, IPv4 TCP (TSO)
  39 #define VIRTIO_NET_HDR_GSO_UDP          3       // GSO frame, IPv4 UDP (UFO)
  40 #define VIRTIO_NET_HDR_GSO_TCPV6        4       // GSO frame, IPv6 TCP
  41 #define VIRTIO_NET_HDR_GSO_ECN          0x80    // TCP has ECN set
  42         __u8 gso_type;
  43         __u16 hdr_len;          /* Ethernet + IP + tcp/udp hdrs */
  44         __u16 gso_size;         /* Bytes to append to hdr_len per frame */
  45         __u16 csum_start;       /* Position to start checksumming from */
  46         __u16 csum_offset;      /* Offset after that to place checksum */
  47 };
  48
  49 /* This is the version of the header to use when the MRG_RXBUF
  50  * feature has been negotiated. */
  51 struct virtio_net_hdr_mrg_rxbuf {
  52         struct virtio_net_hdr hdr;
  53         __u16 num_buffers;      /* Number of merged rx buffers */
  54 };
  55
  56 #endif /* _LINUX_VIRTIO_NET_H */