qemu/hw/virtio-net.c
Alex Williamson 8fd2a2f1a9 virtio-net: Fix MAC filter overflow handling
Overloading the promisc and allmulti flags for indicating filter
table overflow makes it difficult to track the actual requested
operating mode.  Split these out into separate flags.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
2009-06-09 11:38:50 +01:00

665 lines
18 KiB
C

/*
* Virtio Network Device
*
* Copyright IBM, Corp. 2007
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#include "virtio.h"
#include "net.h"
#include "qemu-timer.h"
#include "virtio-net.h"
#define VIRTIO_NET_VM_VERSION 9
#define MAC_TABLE_ENTRIES 32
#define MAX_VLAN (1 << 12) /* Per 802.1Q definition */
typedef struct VirtIONet
{
VirtIODevice vdev;
uint8_t mac[ETH_ALEN];
uint16_t status;
VirtQueue *rx_vq;
VirtQueue *tx_vq;
VirtQueue *ctrl_vq;
VLANClientState *vc;
QEMUTimer *tx_timer;
int tx_timer_active;
int mergeable_rx_bufs;
uint8_t promisc;
uint8_t allmulti;
struct {
int in_use;
uint8_t multi_overflow;
uint8_t uni_overflow;
uint8_t *macs;
} mac_table;
uint32_t *vlans;
} VirtIONet;
/* TODO
* - we could suppress RX interrupt if we were so inclined.
*/
static VirtIONet *to_virtio_net(VirtIODevice *vdev)
{
return (VirtIONet *)vdev;
}
static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
{
VirtIONet *n = to_virtio_net(vdev);
struct virtio_net_config netcfg;
netcfg.status = n->status;
memcpy(netcfg.mac, n->mac, ETH_ALEN);
memcpy(config, &netcfg, sizeof(netcfg));
}
static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
{
VirtIONet *n = to_virtio_net(vdev);
struct virtio_net_config netcfg;
memcpy(&netcfg, config, sizeof(netcfg));
if (memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
memcpy(n->mac, netcfg.mac, ETH_ALEN);
qemu_format_nic_info_str(n->vc, n->mac);
}
}
static void virtio_net_set_link_status(VLANClientState *vc)
{
VirtIONet *n = vc->opaque;
uint16_t old_status = n->status;
if (vc->link_down)
n->status &= ~VIRTIO_NET_S_LINK_UP;
else
n->status |= VIRTIO_NET_S_LINK_UP;
if (n->status != old_status)
virtio_notify_config(&n->vdev);
}
static void virtio_net_reset(VirtIODevice *vdev)
{
VirtIONet *n = to_virtio_net(vdev);
/* Reset back to compatibility mode */
n->promisc = 1;
n->allmulti = 0;
/* Flush any MAC and VLAN filter table state */
n->mac_table.in_use = 0;
n->mac_table.multi_overflow = 0;
n->mac_table.uni_overflow = 0;
memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
memset(n->vlans, 0, MAX_VLAN >> 3);
}
static uint32_t virtio_net_get_features(VirtIODevice *vdev)
{
uint32_t features = (1 << VIRTIO_NET_F_MAC) |
(1 << VIRTIO_NET_F_STATUS) |
(1 << VIRTIO_NET_F_CTRL_VQ) |
(1 << VIRTIO_NET_F_CTRL_RX) |
(1 << VIRTIO_NET_F_CTRL_VLAN);
return features;
}
static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
{
uint32_t features = 0;
/* Linux kernel 2.6.25. It understood MAC (as everyone must),
* but also these: */
features |= (1 << VIRTIO_NET_F_MAC);
features |= (1 << VIRTIO_NET_F_GUEST_CSUM);
features |= (1 << VIRTIO_NET_F_GUEST_TSO4);
features |= (1 << VIRTIO_NET_F_GUEST_TSO6);
features |= (1 << VIRTIO_NET_F_GUEST_ECN);
return features & virtio_net_get_features(vdev);
}
static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
{
VirtIONet *n = to_virtio_net(vdev);
n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF));
}
static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
VirtQueueElement *elem)
{
uint8_t on;
if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(on)) {
fprintf(stderr, "virtio-net ctrl invalid rx mode command\n");
exit(1);
}
on = ldub_p(elem->out_sg[1].iov_base);
if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC)
n->promisc = on;
else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI)
n->allmulti = on;
else
return VIRTIO_NET_ERR;
return VIRTIO_NET_OK;
}
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
VirtQueueElement *elem)
{
struct virtio_net_ctrl_mac mac_data;
if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 ||
elem->out_sg[1].iov_len < sizeof(mac_data) ||
elem->out_sg[2].iov_len < sizeof(mac_data))
return VIRTIO_NET_ERR;
n->mac_table.in_use = 0;
n->mac_table.uni_overflow = 0;
n->mac_table.multi_overflow = 0;
memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
mac_data.entries = ldl_le_p(elem->out_sg[1].iov_base);
if (sizeof(mac_data.entries) +
(mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len)
return VIRTIO_NET_ERR;
if (mac_data.entries <= MAC_TABLE_ENTRIES) {
memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data),
mac_data.entries * ETH_ALEN);
n->mac_table.in_use += mac_data.entries;
} else {
n->mac_table.uni_overflow = 1;
}
mac_data.entries = ldl_le_p(elem->out_sg[2].iov_base);
if (sizeof(mac_data.entries) +
(mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len)
return VIRTIO_NET_ERR;
if (mac_data.entries) {
if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN),
elem->out_sg[2].iov_base + sizeof(mac_data),
mac_data.entries * ETH_ALEN);
n->mac_table.in_use += mac_data.entries;
} else {
n->mac_table.multi_overflow = 1;
}
}
return VIRTIO_NET_OK;
}
static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd,
VirtQueueElement *elem)
{
uint16_t vid;
if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(vid)) {
fprintf(stderr, "virtio-net ctrl invalid vlan command\n");
return VIRTIO_NET_ERR;
}
vid = lduw_le_p(elem->out_sg[1].iov_base);
if (vid >= MAX_VLAN)
return VIRTIO_NET_ERR;
if (cmd == VIRTIO_NET_CTRL_VLAN_ADD)
n->vlans[vid >> 5] |= (1U << (vid & 0x1f));
else if (cmd == VIRTIO_NET_CTRL_VLAN_DEL)
n->vlans[vid >> 5] &= ~(1U << (vid & 0x1f));
else
return VIRTIO_NET_ERR;
return VIRTIO_NET_OK;
}
static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
struct virtio_net_ctrl_hdr ctrl;
virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
VirtQueueElement elem;
while (virtqueue_pop(vq, &elem)) {
if ((elem.in_num < 1) || (elem.out_num < 1)) {
fprintf(stderr, "virtio-net ctrl missing headers\n");
exit(1);
}
if (elem.out_sg[0].iov_len < sizeof(ctrl) ||
elem.in_sg[elem.in_num - 1].iov_len < sizeof(status)) {
fprintf(stderr, "virtio-net ctrl header not in correct element\n");
exit(1);
}
ctrl.class = ldub_p(elem.out_sg[0].iov_base);
ctrl.cmd = ldub_p(elem.out_sg[0].iov_base + sizeof(ctrl.class));
if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE)
status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem);
else if (ctrl.class == VIRTIO_NET_CTRL_MAC)
status = virtio_net_handle_mac(n, ctrl.cmd, &elem);
else if (ctrl.class == VIRTIO_NET_CTRL_VLAN)
status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem);
stb_p(elem.in_sg[elem.in_num - 1].iov_base, status);
virtqueue_push(vq, &elem, sizeof(status));
virtio_notify(vdev, vq);
}
}
/* RX */
static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
qemu_flush_queued_packets(n->vc);
}
static int do_virtio_net_can_receive(VirtIONet *n, int bufsize)
{
if (!virtio_queue_ready(n->rx_vq) ||
!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
return 0;
if (virtio_queue_empty(n->rx_vq) ||
(n->mergeable_rx_bufs &&
!virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
virtio_queue_set_notification(n->rx_vq, 1);
return 0;
}
virtio_queue_set_notification(n->rx_vq, 0);
return 1;
}
static int virtio_net_can_receive(VLANClientState *vc)
{
VirtIONet *n = vc->opaque;
return do_virtio_net_can_receive(n, VIRTIO_NET_MAX_BUFSIZE);
}
static int iov_fill(struct iovec *iov, int iovcnt, const void *buf, int count)
{
int offset, i;
offset = i = 0;
while (offset < count && i < iovcnt) {
int len = MIN(iov[i].iov_len, count - offset);
memcpy(iov[i].iov_base, buf + offset, len);
offset += len;
i++;
}
return offset;
}
static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
const void *buf, size_t size, size_t hdr_len)
{
struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)iov[0].iov_base;
int offset = 0;
hdr->flags = 0;
hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
/* We only ever receive a struct virtio_net_hdr from the tapfd,
* but we may be passing along a larger header to the guest.
*/
iov[0].iov_base += hdr_len;
iov[0].iov_len -= hdr_len;
return offset;
}
static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
{
static const uint8_t bcast[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
static const uint8_t vlan[] = {0x81, 0x00};
uint8_t *ptr = (uint8_t *)buf;
int i;
if (n->promisc)
return 1;
if (!memcmp(&ptr[12], vlan, sizeof(vlan))) {
int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff;
if (!(n->vlans[vid >> 5] & (1U << (vid & 0x1f))))
return 0;
}
if (ptr[0] & 1) { // multicast
if (!memcmp(ptr, bcast, sizeof(bcast))) {
return 1;
} else if (n->allmulti || n->mac_table.multi_overflow) {
return 1;
}
} else { // unicast
if (n->mac_table.uni_overflow) {
return 1;
} else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
return 1;
}
}
for (i = 0; i < n->mac_table.in_use; i++) {
if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN))
return 1;
}
return 0;
}
static ssize_t virtio_net_receive(VLANClientState *vc, const uint8_t *buf, size_t size)
{
VirtIONet *n = vc->opaque;
struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL;
size_t hdr_len, offset, i;
if (!do_virtio_net_can_receive(n, size))
return 0;
if (!receive_filter(n, buf, size))
return size;
/* hdr_len refers to the header we supply to the guest */
hdr_len = n->mergeable_rx_bufs ?
sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
offset = i = 0;
while (offset < size) {
VirtQueueElement elem;
int len, total;
struct iovec sg[VIRTQUEUE_MAX_SIZE];
len = total = 0;
if ((i != 0 && !n->mergeable_rx_bufs) ||
virtqueue_pop(n->rx_vq, &elem) == 0) {
if (i == 0)
return -1;
fprintf(stderr, "virtio-net truncating packet\n");
exit(1);
}
if (elem.in_num < 1) {
fprintf(stderr, "virtio-net receive queue contains no in buffers\n");
exit(1);
}
if (!n->mergeable_rx_bufs && elem.in_sg[0].iov_len != hdr_len) {
fprintf(stderr, "virtio-net header not in first element\n");
exit(1);
}
memcpy(&sg, &elem.in_sg[0], sizeof(sg[0]) * elem.in_num);
if (i == 0) {
if (n->mergeable_rx_bufs)
mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base;
offset += receive_header(n, sg, elem.in_num,
buf + offset, size - offset, hdr_len);
total += hdr_len;
}
/* copy in packet. ugh */
len = iov_fill(sg, elem.in_num,
buf + offset, size - offset);
total += len;
/* signal other side */
virtqueue_fill(n->rx_vq, &elem, total, i++);
offset += len;
}
if (mhdr)
mhdr->num_buffers = i;
virtqueue_flush(n->rx_vq, i);
virtio_notify(&n->vdev, n->rx_vq);
return size;
}
/* TX */
static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
{
VirtQueueElement elem;
int has_vnet_hdr = 0;
if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
return;
while (virtqueue_pop(vq, &elem)) {
ssize_t len = 0;
unsigned int out_num = elem.out_num;
struct iovec *out_sg = &elem.out_sg[0];
unsigned hdr_len;
/* hdr_len refers to the header received from the guest */
hdr_len = n->mergeable_rx_bufs ?
sizeof(struct virtio_net_hdr_mrg_rxbuf) :
sizeof(struct virtio_net_hdr);
if (out_num < 1 || out_sg->iov_len != hdr_len) {
fprintf(stderr, "virtio-net header not in first element\n");
exit(1);
}
/* ignore the header if GSO is not supported */
if (!has_vnet_hdr) {
out_num--;
out_sg++;
len += hdr_len;
} else if (n->mergeable_rx_bufs) {
/* tapfd expects a struct virtio_net_hdr */
hdr_len -= sizeof(struct virtio_net_hdr);
out_sg->iov_len -= hdr_len;
len += hdr_len;
}
len += qemu_sendv_packet(n->vc, out_sg, out_num);
virtqueue_push(vq, &elem, len);
virtio_notify(&n->vdev, vq);
}
}
static void virtio_net_handle_tx(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
if (n->tx_timer_active) {
virtio_queue_set_notification(vq, 1);
qemu_del_timer(n->tx_timer);
n->tx_timer_active = 0;
virtio_net_flush_tx(n, vq);
} else {
qemu_mod_timer(n->tx_timer,
qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
n->tx_timer_active = 1;
virtio_queue_set_notification(vq, 0);
}
}
static void virtio_net_tx_timer(void *opaque)
{
VirtIONet *n = opaque;
n->tx_timer_active = 0;
/* Just in case the driver is not ready on more */
if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
return;
virtio_queue_set_notification(n->tx_vq, 1);
virtio_net_flush_tx(n, n->tx_vq);
}
static void virtio_net_save(QEMUFile *f, void *opaque)
{
VirtIONet *n = opaque;
virtio_save(&n->vdev, f);
qemu_put_buffer(f, n->mac, ETH_ALEN);
qemu_put_be32(f, n->tx_timer_active);
qemu_put_be32(f, n->mergeable_rx_bufs);
qemu_put_be16(f, n->status);
qemu_put_byte(f, n->promisc);
qemu_put_byte(f, n->allmulti);
qemu_put_be32(f, n->mac_table.in_use);
qemu_put_buffer(f, n->mac_table.macs, n->mac_table.in_use * ETH_ALEN);
qemu_put_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
qemu_put_be32(f, 0); /* vnet-hdr placeholder */
qemu_put_byte(f, n->mac_table.multi_overflow);
qemu_put_byte(f, n->mac_table.uni_overflow);
}
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
{
VirtIONet *n = opaque;
if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
return -EINVAL;
virtio_load(&n->vdev, f);
qemu_get_buffer(f, n->mac, ETH_ALEN);
n->tx_timer_active = qemu_get_be32(f);
n->mergeable_rx_bufs = qemu_get_be32(f);
if (version_id >= 3)
n->status = qemu_get_be16(f);
if (version_id >= 4) {
if (version_id < 8) {
n->promisc = qemu_get_be32(f);
n->allmulti = qemu_get_be32(f);
} else {
n->promisc = qemu_get_byte(f);
n->allmulti = qemu_get_byte(f);
}
}
if (version_id >= 5) {
n->mac_table.in_use = qemu_get_be32(f);
/* MAC_TABLE_ENTRIES may be different from the saved image */
if (n->mac_table.in_use <= MAC_TABLE_ENTRIES) {
qemu_get_buffer(f, n->mac_table.macs,
n->mac_table.in_use * ETH_ALEN);
} else if (n->mac_table.in_use) {
qemu_fseek(f, n->mac_table.in_use * ETH_ALEN, SEEK_CUR);
n->mac_table.multi_overflow = n->mac_table.uni_overflow = 1;
n->mac_table.in_use = 0;
}
}
if (version_id >= 6)
qemu_get_buffer(f, (uint8_t *)n->vlans, MAX_VLAN >> 3);
if (version_id >= 7 && qemu_get_be32(f)) {
fprintf(stderr,
"virtio-net: saved image requires vnet header support\n");
exit(1);
}
if (version_id >= 9) {
n->mac_table.multi_overflow = qemu_get_byte(f);
n->mac_table.uni_overflow = qemu_get_byte(f);
}
if (n->tx_timer_active) {
qemu_mod_timer(n->tx_timer,
qemu_get_clock(vm_clock) + TX_TIMER_INTERVAL);
}
return 0;
}
static void virtio_net_cleanup(VLANClientState *vc)
{
VirtIONet *n = vc->opaque;
unregister_savevm("virtio-net", n);
qemu_free(n->mac_table.macs);
qemu_free(n->vlans);
qemu_del_timer(n->tx_timer);
qemu_free_timer(n->tx_timer);
virtio_cleanup(&n->vdev);
}
VirtIODevice *virtio_net_init(DeviceState *dev)
{
VirtIONet *n;
static int virtio_net_id;
n = (VirtIONet *)virtio_common_init("virtio-net", VIRTIO_ID_NET,
sizeof(struct virtio_net_config),
sizeof(VirtIONet));
n->vdev.get_config = virtio_net_get_config;
n->vdev.set_config = virtio_net_set_config;
n->vdev.get_features = virtio_net_get_features;
n->vdev.set_features = virtio_net_set_features;
n->vdev.bad_features = virtio_net_bad_features;
n->vdev.reset = virtio_net_reset;
n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx);
n->ctrl_vq = virtio_add_queue(&n->vdev, 16, virtio_net_handle_ctrl);
qdev_get_macaddr(dev, n->mac);
n->status = VIRTIO_NET_S_LINK_UP;
n->vc = qdev_get_vlan_client(dev,
virtio_net_can_receive,
virtio_net_receive, NULL,
virtio_net_cleanup, n);
n->vc->link_status_changed = virtio_net_set_link_status;
qemu_format_nic_info_str(n->vc, n->mac);
n->tx_timer = qemu_new_timer(vm_clock, virtio_net_tx_timer, n);
n->tx_timer_active = 0;
n->mergeable_rx_bufs = 0;
n->promisc = 1; /* for compatibility */
n->mac_table.macs = qemu_mallocz(MAC_TABLE_ENTRIES * ETH_ALEN);
n->vlans = qemu_mallocz(MAX_VLAN >> 3);
register_savevm("virtio-net", virtio_net_id++, VIRTIO_NET_VM_VERSION,
virtio_net_save, virtio_net_load, n);
return &n->vdev;
}