virtio: simplify config mechanism.

Previously we used a type/len pair within the config space, but this
seems overkill.  We now simply define a structure which represents the
layout in the config space: the config space can now only be extended
at the end.

The main driver-visible changes:
1) We indicate what fields are present with an explicit feature bit.
2) Virtqueues are explicitly numbered, and not in the config space.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2008-02-04 23:49:56 -05:00
parent f35d9d8aae
commit a586d4f601
11 changed files with 278 additions and 279 deletions

View file

@ -5,16 +5,19 @@
/* The ID for virtio_net */
#define VIRTIO_ID_NET 1
/* The bitmap of config for virtio net */
#define VIRTIO_CONFIG_NET_F 0x40
/* 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
/* The config defining mac address. */
#define VIRTIO_CONFIG_NET_MAC_F 0x41
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. */