lguest: Convert net device to virtio 1.0 PCI.

The only real change here (other than using the PCI bus) is that we
didn't negotiate VIRTIO_NET_F_MRG_RXBUF before, so the format of the
packet header changed with virtio 1.0; we need TUNSETVNETHDRSZ on the
tun fd to tell it about the extra two bytes.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2015-02-11 15:16:01 +10:30
parent 5051654764
commit bf6d40344d

View File

@ -68,7 +68,7 @@ typedef uint8_t u8;
/* Use in-kernel ones, which defines VIRTIO_F_VERSION_1 */
#include "../../include/uapi/linux/virtio_config.h"
#include <linux/virtio_net.h>
#include "../../include/uapi/linux/virtio_net.h"
#include "../../include/uapi/linux/virtio_blk.h"
#include <linux/virtio_console.h>
#include <linux/virtio_rng.h>
@ -2224,7 +2224,6 @@ static void init_pci_config(struct pci_config *pci, u16 type,
*
* eg :
* VIRTIO_ID_CONSOLE: class = 0x07, subclass = 0x00
* VIRTIO_ID_NET: class = 0x02, subclass = 0x00
* VIRTIO_ID_RNG: class = 0xff, subclass = 0
*/
pci->class = class;
@ -2485,6 +2484,7 @@ static void configure_device(int fd, const char *tapif, u32 ipaddr)
static int get_tun_device(char tapif[IFNAMSIZ])
{
struct ifreq ifr;
int vnet_hdr_sz;
int netfd;
/* Start with this zeroed. Messy but sure. */
@ -2512,6 +2512,18 @@ static int get_tun_device(char tapif[IFNAMSIZ])
*/
ioctl(netfd, TUNSETNOCSUM, 1);
/*
* In virtio before 1.0 (aka legacy virtio), we added a 16-bit
* field at the end of the network header iff
* VIRTIO_NET_F_MRG_RXBUF was negotiated. For virtio 1.0,
* that became the norm, but we need to tell the tun device
* about our expanded header (which is called
* virtio_net_hdr_mrg_rxbuf in the legacy system).
*/
vnet_hdr_sz = sizeof(struct virtio_net_hdr_mrg_rxbuf);
if (ioctl(netfd, TUNSETVNETHDRSZ, &vnet_hdr_sz) != 0)
err(1, "Setting tun header size to %u", vnet_hdr_sz);
memcpy(tapif, ifr.ifr_name, IFNAMSIZ);
return netfd;
}
@ -2535,12 +2547,12 @@ static void setup_tun_net(char *arg)
net_info->tunfd = get_tun_device(tapif);
/* First we create a new network device. */
dev = new_device("net", VIRTIO_ID_NET);
dev = new_pci_device("net", VIRTIO_ID_NET, 0x02, 0x00);
dev->priv = net_info;
/* Network devices need a recv and a send queue, just like console. */
add_virtqueue(dev, VIRTQUEUE_NUM, net_input);
add_virtqueue(dev, VIRTQUEUE_NUM, net_output);
add_pci_virtqueue(dev, net_input);
add_pci_virtqueue(dev, net_output);
/*
* We need a socket to perform the magic network ioctls to bring up the
@ -2560,7 +2572,7 @@ static void setup_tun_net(char *arg)
p = strchr(arg, ':');
if (p) {
str2mac(p+1, conf.mac);
add_feature(dev, VIRTIO_NET_F_MAC);
add_pci_feature(dev, VIRTIO_NET_F_MAC);
*p = '\0';
}
@ -2574,25 +2586,21 @@ static void setup_tun_net(char *arg)
configure_device(ipfd, tapif, ip);
/* Expect Guest to handle everything except UFO */
add_feature(dev, VIRTIO_NET_F_CSUM);
add_feature(dev, VIRTIO_NET_F_GUEST_CSUM);
add_feature(dev, VIRTIO_NET_F_GUEST_TSO4);
add_feature(dev, VIRTIO_NET_F_GUEST_TSO6);
add_feature(dev, VIRTIO_NET_F_GUEST_ECN);
add_feature(dev, VIRTIO_NET_F_HOST_TSO4);
add_feature(dev, VIRTIO_NET_F_HOST_TSO6);
add_feature(dev, VIRTIO_NET_F_HOST_ECN);
add_pci_feature(dev, VIRTIO_NET_F_CSUM);
add_pci_feature(dev, VIRTIO_NET_F_GUEST_CSUM);
add_pci_feature(dev, VIRTIO_NET_F_GUEST_TSO4);
add_pci_feature(dev, VIRTIO_NET_F_GUEST_TSO6);
add_pci_feature(dev, VIRTIO_NET_F_GUEST_ECN);
add_pci_feature(dev, VIRTIO_NET_F_HOST_TSO4);
add_pci_feature(dev, VIRTIO_NET_F_HOST_TSO6);
add_pci_feature(dev, VIRTIO_NET_F_HOST_ECN);
/* We handle indirect ring entries */
add_feature(dev, VIRTIO_RING_F_INDIRECT_DESC);
/* We're compliant with the damn spec. */
add_feature(dev, VIRTIO_F_ANY_LAYOUT);
set_config(dev, sizeof(conf), &conf);
add_pci_feature(dev, VIRTIO_RING_F_INDIRECT_DESC);
set_device_config(dev, &conf, sizeof(conf));
/* We don't need the socket any more; setup is done. */
close(ipfd);
devices.device_num++;
if (bridging)
verbose("device %u: tun %s attached to bridge: %s\n",
devices.device_num, tapif, arg);