qemu/hw/virtio-net.c
Anthony Liguori 404e7a4f4a virtio,pci,qom
Work by Alex to support VGA assignment,
 pci and virtio fixes by Stefan, Jason and myself, and a
 new qmp event for hotplug support by myself.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'mst/tags/for_anthony' into staging

virtio,pci,qom

Work by Alex to support VGA assignment,
pci and virtio fixes by Stefan, Jason and myself, and a
new qmp event for hotplug support by myself.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Tue 26 Mar 2013 02:02:24 PM CDT using RSA key ID D28D5469
# gpg: Can't check signature: public key not found

# By Alex Williamson (13) and others
# Via Michael S. Tsirkin
* mst/tags/for_anthony: (23 commits)
  pcie: Add endpoint capability initialization wrapper
  roms: switch oldnoconfig to olddefconfig
  pcie: Mangle types to match topology
  pci: Create and use API to determine root buses
  pci: Create pci_bus_is_express helper
  pci: Q35, Root Ports, and Switches create PCI Express buses
  pci: Allow PCI bus creation interfaces to specify the type of bus
  pci: Move PCI and PCIE type defines
  pci: Create and register a new PCI Express TypeInfo
  exec: assert that RAMBlock size is non-zero
  pci: refuse empty ROM files
  pci_bridge: Remove duplicate IRQ swizzle function
  pci_bridge: Use a default map_irq function
  pci: Fix INTx routing notifier recursion
  pci_bridge: drop formatting from source
  pci_bridge: factor out common code
  pci: Teach PCI Bridges about VGA routing
  pci: Add PCI VGA helpers
  virtio-pci: guest notifier mask without non-irqfd
  virtio-net: remove layout assumptions for mq ctrl
  ...
2013-03-26 16:16:43 -05:00

1371 lines
40 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 "qemu/iov.h"
#include "hw/virtio.h"
#include "net/net.h"
#include "net/checksum.h"
#include "net/tap.h"
#include "qemu/error-report.h"
#include "qemu/timer.h"
#include "hw/virtio-net.h"
#include "hw/vhost_net.h"
#define VIRTIO_NET_VM_VERSION 11
#define MAC_TABLE_ENTRIES 64
#define MAX_VLAN (1 << 12) /* Per 802.1Q definition */
/*
* Calculate the number of bytes up to and including the given 'field' of
* 'container'.
*/
#define endof(container, field) \
(offsetof(container, field) + sizeof(((container *)0)->field))
typedef struct VirtIOFeature {
uint32_t flags;
size_t end;
} VirtIOFeature;
static VirtIOFeature feature_sizes[] = {
{.flags = 1 << VIRTIO_NET_F_MAC,
.end = endof(struct virtio_net_config, mac)},
{.flags = 1 << VIRTIO_NET_F_STATUS,
.end = endof(struct virtio_net_config, status)},
{.flags = 1 << VIRTIO_NET_F_MQ,
.end = endof(struct virtio_net_config, max_virtqueue_pairs)},
{}
};
static VirtIONetQueue *virtio_net_get_subqueue(NetClientState *nc)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
return &n->vqs[nc->queue_index];
}
static int vq2q(int queue_index)
{
return queue_index / 2;
}
/* 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;
stw_p(&netcfg.status, n->status);
stw_p(&netcfg.max_virtqueue_pairs, n->max_queues);
memcpy(netcfg.mac, n->mac, ETH_ALEN);
memcpy(config, &netcfg, n->config_size);
}
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, n->config_size);
if (!(n->vdev.guest_features >> VIRTIO_NET_F_CTRL_MAC_ADDR & 1) &&
memcmp(netcfg.mac, n->mac, ETH_ALEN)) {
memcpy(n->mac, netcfg.mac, ETH_ALEN);
qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
}
}
static bool virtio_net_started(VirtIONet *n, uint8_t status)
{
return (status & VIRTIO_CONFIG_S_DRIVER_OK) &&
(n->status & VIRTIO_NET_S_LINK_UP) && n->vdev.vm_running;
}
static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
{
NetClientState *nc = qemu_get_queue(n->nic);
int queues = n->multiqueue ? n->max_queues : 1;
if (!nc->peer) {
return;
}
if (nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
return;
}
if (!tap_get_vhost_net(nc->peer)) {
return;
}
if (!!n->vhost_started == virtio_net_started(n, status) &&
!nc->peer->link_down) {
return;
}
if (!n->vhost_started) {
int r;
if (!vhost_net_query(tap_get_vhost_net(nc->peer), &n->vdev)) {
return;
}
n->vhost_started = 1;
r = vhost_net_start(&n->vdev, n->nic->ncs, queues);
if (r < 0) {
error_report("unable to start vhost net: %d: "
"falling back on userspace virtio", -r);
n->vhost_started = 0;
}
} else {
vhost_net_stop(&n->vdev, n->nic->ncs, queues);
n->vhost_started = 0;
}
}
static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
{
VirtIONet *n = to_virtio_net(vdev);
VirtIONetQueue *q;
int i;
uint8_t queue_status;
virtio_net_vhost_status(n, status);
for (i = 0; i < n->max_queues; i++) {
q = &n->vqs[i];
if ((!n->multiqueue && i != 0) || i >= n->curr_queues) {
queue_status = 0;
} else {
queue_status = status;
}
if (!q->tx_waiting) {
continue;
}
if (virtio_net_started(n, queue_status) && !n->vhost_started) {
if (q->tx_timer) {
qemu_mod_timer(q->tx_timer,
qemu_get_clock_ns(vm_clock) + n->tx_timeout);
} else {
qemu_bh_schedule(q->tx_bh);
}
} else {
if (q->tx_timer) {
qemu_del_timer(q->tx_timer);
} else {
qemu_bh_cancel(q->tx_bh);
}
}
}
}
static void virtio_net_set_link_status(NetClientState *nc)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
uint16_t old_status = n->status;
if (nc->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);
virtio_net_set_status(&n->vdev, n->vdev.status);
}
static void virtio_net_reset(VirtIODevice *vdev)
{
VirtIONet *n = to_virtio_net(vdev);
/* Reset back to compatibility mode */
n->promisc = 1;
n->allmulti = 0;
n->alluni = 0;
n->nomulti = 0;
n->nouni = 0;
n->nobcast = 0;
/* multiqueue is disabled by default */
n->curr_queues = 1;
/* Flush any MAC and VLAN filter table state */
n->mac_table.in_use = 0;
n->mac_table.first_multi = 0;
n->mac_table.multi_overflow = 0;
n->mac_table.uni_overflow = 0;
memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
memcpy(&n->mac[0], &n->nic->conf->macaddr, sizeof(n->mac));
memset(n->vlans, 0, MAX_VLAN >> 3);
}
static void peer_test_vnet_hdr(VirtIONet *n)
{
NetClientState *nc = qemu_get_queue(n->nic);
if (!nc->peer) {
return;
}
if (nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
return;
}
n->has_vnet_hdr = tap_has_vnet_hdr(nc->peer);
}
static int peer_has_vnet_hdr(VirtIONet *n)
{
return n->has_vnet_hdr;
}
static int peer_has_ufo(VirtIONet *n)
{
if (!peer_has_vnet_hdr(n))
return 0;
n->has_ufo = tap_has_ufo(qemu_get_queue(n->nic)->peer);
return n->has_ufo;
}
static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs)
{
int i;
NetClientState *nc;
n->mergeable_rx_bufs = mergeable_rx_bufs;
n->guest_hdr_len = n->mergeable_rx_bufs ?
sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr);
for (i = 0; i < n->max_queues; i++) {
nc = qemu_get_subqueue(n->nic, i);
if (peer_has_vnet_hdr(n) &&
tap_has_vnet_hdr_len(nc->peer, n->guest_hdr_len)) {
tap_set_vnet_hdr_len(nc->peer, n->guest_hdr_len);
n->host_hdr_len = n->guest_hdr_len;
}
}
}
static int peer_attach(VirtIONet *n, int index)
{
NetClientState *nc = qemu_get_subqueue(n->nic, index);
if (!nc->peer) {
return 0;
}
if (nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
return 0;
}
return tap_enable(nc->peer);
}
static int peer_detach(VirtIONet *n, int index)
{
NetClientState *nc = qemu_get_subqueue(n->nic, index);
if (!nc->peer) {
return 0;
}
if (nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
return 0;
}
return tap_disable(nc->peer);
}
static void virtio_net_set_queues(VirtIONet *n)
{
int i;
for (i = 0; i < n->max_queues; i++) {
if (i < n->curr_queues) {
assert(!peer_attach(n, i));
} else {
assert(!peer_detach(n, i));
}
}
}
static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue, int ctrl);
static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
{
VirtIONet *n = to_virtio_net(vdev);
NetClientState *nc = qemu_get_queue(n->nic);
features |= (1 << VIRTIO_NET_F_MAC);
if (!peer_has_vnet_hdr(n)) {
features &= ~(0x1 << VIRTIO_NET_F_CSUM);
features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO4);
features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO6);
features &= ~(0x1 << VIRTIO_NET_F_HOST_ECN);
features &= ~(0x1 << VIRTIO_NET_F_GUEST_CSUM);
features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO4);
features &= ~(0x1 << VIRTIO_NET_F_GUEST_TSO6);
features &= ~(0x1 << VIRTIO_NET_F_GUEST_ECN);
}
if (!peer_has_vnet_hdr(n) || !peer_has_ufo(n)) {
features &= ~(0x1 << VIRTIO_NET_F_GUEST_UFO);
features &= ~(0x1 << VIRTIO_NET_F_HOST_UFO);
}
if (!nc->peer || nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
return features;
}
if (!tap_get_vhost_net(nc->peer)) {
return features;
}
return vhost_net_get_features(tap_get_vhost_net(nc->peer), 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_CSUM);
features |= (1 << VIRTIO_NET_F_HOST_TSO4);
features |= (1 << VIRTIO_NET_F_HOST_TSO6);
features |= (1 << VIRTIO_NET_F_HOST_ECN);
return features;
}
static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features)
{
VirtIONet *n = to_virtio_net(vdev);
int i;
virtio_net_set_multiqueue(n, !!(features & (1 << VIRTIO_NET_F_MQ)),
!!(features & (1 << VIRTIO_NET_F_CTRL_VQ)));
virtio_net_set_mrg_rx_bufs(n, !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF)));
if (n->has_vnet_hdr) {
tap_set_offload(qemu_get_subqueue(n->nic, 0)->peer,
(features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
(features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
(features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
(features >> VIRTIO_NET_F_GUEST_ECN) & 1,
(features >> VIRTIO_NET_F_GUEST_UFO) & 1);
}
for (i = 0; i < n->max_queues; i++) {
NetClientState *nc = qemu_get_subqueue(n->nic, i);
if (!nc->peer || nc->peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) {
continue;
}
if (!tap_get_vhost_net(nc->peer)) {
continue;
}
vhost_net_ack_features(tap_get_vhost_net(nc->peer), features);
}
}
static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd,
struct iovec *iov, unsigned int iov_cnt)
{
uint8_t on;
size_t s;
s = iov_to_buf(iov, iov_cnt, 0, &on, sizeof(on));
if (s != sizeof(on)) {
return VIRTIO_NET_ERR;
}
if (cmd == VIRTIO_NET_CTRL_RX_PROMISC) {
n->promisc = on;
} else if (cmd == VIRTIO_NET_CTRL_RX_ALLMULTI) {
n->allmulti = on;
} else if (cmd == VIRTIO_NET_CTRL_RX_ALLUNI) {
n->alluni = on;
} else if (cmd == VIRTIO_NET_CTRL_RX_NOMULTI) {
n->nomulti = on;
} else if (cmd == VIRTIO_NET_CTRL_RX_NOUNI) {
n->nouni = on;
} else if (cmd == VIRTIO_NET_CTRL_RX_NOBCAST) {
n->nobcast = on;
} else {
return VIRTIO_NET_ERR;
}
return VIRTIO_NET_OK;
}
static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd,
struct iovec *iov, unsigned int iov_cnt)
{
struct virtio_net_ctrl_mac mac_data;
size_t s;
if (cmd == VIRTIO_NET_CTRL_MAC_ADDR_SET) {
if (iov_size(iov, iov_cnt) != sizeof(n->mac)) {
return VIRTIO_NET_ERR;
}
s = iov_to_buf(iov, iov_cnt, 0, &n->mac, sizeof(n->mac));
assert(s == sizeof(n->mac));
qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac);
return VIRTIO_NET_OK;
}
if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET) {
return VIRTIO_NET_ERR;
}
n->mac_table.in_use = 0;
n->mac_table.first_multi = 0;
n->mac_table.uni_overflow = 0;
n->mac_table.multi_overflow = 0;
memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN);
s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
sizeof(mac_data.entries));
mac_data.entries = ldl_p(&mac_data.entries);
if (s != sizeof(mac_data.entries)) {
return VIRTIO_NET_ERR;
}
iov_discard_front(&iov, &iov_cnt, s);
if (mac_data.entries * ETH_ALEN > iov_size(iov, iov_cnt)) {
return VIRTIO_NET_ERR;
}
if (mac_data.entries <= MAC_TABLE_ENTRIES) {
s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs,
mac_data.entries * ETH_ALEN);
if (s != mac_data.entries * ETH_ALEN) {
return VIRTIO_NET_ERR;
}
n->mac_table.in_use += mac_data.entries;
} else {
n->mac_table.uni_overflow = 1;
}
iov_discard_front(&iov, &iov_cnt, mac_data.entries * ETH_ALEN);
n->mac_table.first_multi = n->mac_table.in_use;
s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries,
sizeof(mac_data.entries));
mac_data.entries = ldl_p(&mac_data.entries);
if (s != sizeof(mac_data.entries)) {
return VIRTIO_NET_ERR;
}
iov_discard_front(&iov, &iov_cnt, s);
if (mac_data.entries * ETH_ALEN != iov_size(iov, iov_cnt)) {
return VIRTIO_NET_ERR;
}
if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) {
s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs,
mac_data.entries * ETH_ALEN);
if (s != mac_data.entries * ETH_ALEN) {
return VIRTIO_NET_ERR;
}
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,
struct iovec *iov, unsigned int iov_cnt)
{
uint16_t vid;
size_t s;
s = iov_to_buf(iov, iov_cnt, 0, &vid, sizeof(vid));
vid = lduw_p(&vid);
if (s != sizeof(vid)) {
return VIRTIO_NET_ERR;
}
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 int virtio_net_handle_mq(VirtIONet *n, uint8_t cmd,
struct iovec *iov, unsigned int iov_cnt)
{
struct virtio_net_ctrl_mq mq;
size_t s;
uint16_t queues;
s = iov_to_buf(iov, iov_cnt, 0, &mq, sizeof(mq));
if (s != sizeof(mq)) {
return VIRTIO_NET_ERR;
}
if (cmd != VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
return VIRTIO_NET_ERR;
}
queues = lduw_p(&mq.virtqueue_pairs);
if (queues < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
queues > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
queues > n->max_queues ||
!n->multiqueue) {
return VIRTIO_NET_ERR;
}
n->curr_queues = queues;
/* stop the backend before changing the number of queues to avoid handling a
* disabled queue */
virtio_net_set_status(&n->vdev, n->vdev.status);
virtio_net_set_queues(n);
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;
size_t s;
struct iovec *iov;
unsigned int iov_cnt;
while (virtqueue_pop(vq, &elem)) {
if (iov_size(elem.in_sg, elem.in_num) < sizeof(status) ||
iov_size(elem.out_sg, elem.out_num) < sizeof(ctrl)) {
error_report("virtio-net ctrl missing headers");
exit(1);
}
iov = elem.out_sg;
iov_cnt = elem.out_num;
s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl));
iov_discard_front(&iov, &iov_cnt, sizeof(ctrl));
if (s != sizeof(ctrl)) {
status = VIRTIO_NET_ERR;
} else if (ctrl.class == VIRTIO_NET_CTRL_RX) {
status = virtio_net_handle_rx_mode(n, ctrl.cmd, iov, iov_cnt);
} else if (ctrl.class == VIRTIO_NET_CTRL_MAC) {
status = virtio_net_handle_mac(n, ctrl.cmd, iov, iov_cnt);
} else if (ctrl.class == VIRTIO_NET_CTRL_VLAN) {
status = virtio_net_handle_vlan_table(n, ctrl.cmd, iov, iov_cnt);
} else if (ctrl.class == VIRTIO_NET_CTRL_MQ) {
status = virtio_net_handle_mq(n, ctrl.cmd, iov, iov_cnt);
}
s = iov_from_buf(elem.in_sg, elem.in_num, 0, &status, sizeof(status));
assert(s == sizeof(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);
int queue_index = vq2q(virtio_get_queue_index(vq));
qemu_flush_queued_packets(qemu_get_subqueue(n->nic, queue_index));
}
static int virtio_net_can_receive(NetClientState *nc)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
VirtIONetQueue *q = virtio_net_get_subqueue(nc);
if (!n->vdev.vm_running) {
return 0;
}
if (nc->queue_index >= n->curr_queues) {
return 0;
}
if (!virtio_queue_ready(q->rx_vq) ||
!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)) {
return 0;
}
return 1;
}
static int virtio_net_has_buffers(VirtIONetQueue *q, int bufsize)
{
VirtIONet *n = q->n;
if (virtio_queue_empty(q->rx_vq) ||
(n->mergeable_rx_bufs &&
!virtqueue_avail_bytes(q->rx_vq, bufsize, 0))) {
virtio_queue_set_notification(q->rx_vq, 1);
/* To avoid a race condition where the guest has made some buffers
* available after the above check but before notification was
* enabled, check for available buffers again.
*/
if (virtio_queue_empty(q->rx_vq) ||
(n->mergeable_rx_bufs &&
!virtqueue_avail_bytes(q->rx_vq, bufsize, 0))) {
return 0;
}
}
virtio_queue_set_notification(q->rx_vq, 0);
return 1;
}
/* dhclient uses AF_PACKET but doesn't pass auxdata to the kernel so
* it never finds out that the packets don't have valid checksums. This
* causes dhclient to get upset. Fedora's carried a patch for ages to
* fix this with Xen but it hasn't appeared in an upstream release of
* dhclient yet.
*
* To avoid breaking existing guests, we catch udp packets and add
* checksums. This is terrible but it's better than hacking the guest
* kernels.
*
* N.B. if we introduce a zero-copy API, this operation is no longer free so
* we should provide a mechanism to disable it to avoid polluting the host
* cache.
*/
static void work_around_broken_dhclient(struct virtio_net_hdr *hdr,
uint8_t *buf, size_t size)
{
if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */
(size > 27 && size < 1500) && /* normal sized MTU */
(buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */
(buf[23] == 17) && /* ip.protocol == UDP */
(buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */
net_checksum_calculate(buf, size);
hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM;
}
}
static void receive_header(VirtIONet *n, const struct iovec *iov, int iov_cnt,
const void *buf, size_t size)
{
if (n->has_vnet_hdr) {
/* FIXME this cast is evil */
void *wbuf = (void *)buf;
work_around_broken_dhclient(wbuf, wbuf + n->host_hdr_len,
size - n->host_hdr_len);
iov_from_buf(iov, iov_cnt, 0, buf, sizeof(struct virtio_net_hdr));
} else {
struct virtio_net_hdr hdr = {
.flags = 0,
.gso_type = VIRTIO_NET_HDR_GSO_NONE
};
iov_from_buf(iov, iov_cnt, 0, &hdr, sizeof hdr);
}
}
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;
ptr += n->host_hdr_len;
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 !n->nobcast;
} else if (n->nomulti) {
return 0;
} else if (n->allmulti || n->mac_table.multi_overflow) {
return 1;
}
for (i = n->mac_table.first_multi; i < n->mac_table.in_use; i++) {
if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
return 1;
}
}
} else { // unicast
if (n->nouni) {
return 0;
} else if (n->alluni || n->mac_table.uni_overflow) {
return 1;
} else if (!memcmp(ptr, n->mac, ETH_ALEN)) {
return 1;
}
for (i = 0; i < n->mac_table.first_multi; i++) {
if (!memcmp(ptr, &n->mac_table.macs[i * ETH_ALEN], ETH_ALEN)) {
return 1;
}
}
}
return 0;
}
static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
VirtIONetQueue *q = virtio_net_get_subqueue(nc);
struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE];
struct virtio_net_hdr_mrg_rxbuf mhdr;
unsigned mhdr_cnt = 0;
size_t offset, i, guest_offset;
if (!virtio_net_can_receive(nc)) {
return -1;
}
/* hdr_len refers to the header we supply to the guest */
if (!virtio_net_has_buffers(q, size + n->guest_hdr_len - n->host_hdr_len)) {
return 0;
}
if (!receive_filter(n, buf, size))
return size;
offset = i = 0;
while (offset < size) {
VirtQueueElement elem;
int len, total;
const struct iovec *sg = elem.in_sg;
total = 0;
if (virtqueue_pop(q->rx_vq, &elem) == 0) {
if (i == 0)
return -1;
error_report("virtio-net unexpected empty queue: "
"i %zd mergeable %d offset %zd, size %zd, "
"guest hdr len %zd, host hdr len %zd guest features 0x%x",
i, n->mergeable_rx_bufs, offset, size,
n->guest_hdr_len, n->host_hdr_len, n->vdev.guest_features);
exit(1);
}
if (elem.in_num < 1) {
error_report("virtio-net receive queue contains no in buffers");
exit(1);
}
if (i == 0) {
assert(offset == 0);
if (n->mergeable_rx_bufs) {
mhdr_cnt = iov_copy(mhdr_sg, ARRAY_SIZE(mhdr_sg),
sg, elem.in_num,
offsetof(typeof(mhdr), num_buffers),
sizeof(mhdr.num_buffers));
}
receive_header(n, sg, elem.in_num, buf, size);
offset = n->host_hdr_len;
total += n->guest_hdr_len;
guest_offset = n->guest_hdr_len;
} else {
guest_offset = 0;
}
/* copy in packet. ugh */
len = iov_from_buf(sg, elem.in_num, guest_offset,
buf + offset, size - offset);
total += len;
offset += len;
/* If buffers can't be merged, at this point we
* must have consumed the complete packet.
* Otherwise, drop it. */
if (!n->mergeable_rx_bufs && offset < size) {
#if 0
error_report("virtio-net truncated non-mergeable packet: "
"i %zd mergeable %d offset %zd, size %zd, "
"guest hdr len %zd, host hdr len %zd",
i, n->mergeable_rx_bufs,
offset, size, n->guest_hdr_len, n->host_hdr_len);
#endif
return size;
}
/* signal other side */
virtqueue_fill(q->rx_vq, &elem, total, i++);
}
if (mhdr_cnt) {
stw_p(&mhdr.num_buffers, i);
iov_from_buf(mhdr_sg, mhdr_cnt,
0,
&mhdr.num_buffers, sizeof mhdr.num_buffers);
}
virtqueue_flush(q->rx_vq, i);
virtio_notify(&n->vdev, q->rx_vq);
return size;
}
static int32_t virtio_net_flush_tx(VirtIONetQueue *q);
static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
VirtIONetQueue *q = virtio_net_get_subqueue(nc);
virtqueue_push(q->tx_vq, &q->async_tx.elem, 0);
virtio_notify(&n->vdev, q->tx_vq);
q->async_tx.elem.out_num = q->async_tx.len = 0;
virtio_queue_set_notification(q->tx_vq, 1);
virtio_net_flush_tx(q);
}
/* TX */
static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
{
VirtIONet *n = q->n;
VirtQueueElement elem;
int32_t num_packets = 0;
int queue_index = vq2q(virtio_get_queue_index(q->tx_vq));
if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)) {
return num_packets;
}
assert(n->vdev.vm_running);
if (q->async_tx.elem.out_num) {
virtio_queue_set_notification(q->tx_vq, 0);
return num_packets;
}
while (virtqueue_pop(q->tx_vq, &elem)) {
ssize_t ret, len;
unsigned int out_num = elem.out_num;
struct iovec *out_sg = &elem.out_sg[0];
struct iovec sg[VIRTQUEUE_MAX_SIZE];
if (out_num < 1) {
error_report("virtio-net header not in first element");
exit(1);
}
/*
* If host wants to see the guest header as is, we can
* pass it on unchanged. Otherwise, copy just the parts
* that host is interested in.
*/
assert(n->host_hdr_len <= n->guest_hdr_len);
if (n->host_hdr_len != n->guest_hdr_len) {
unsigned sg_num = iov_copy(sg, ARRAY_SIZE(sg),
out_sg, out_num,
0, n->host_hdr_len);
sg_num += iov_copy(sg + sg_num, ARRAY_SIZE(sg) - sg_num,
out_sg, out_num,
n->guest_hdr_len, -1);
out_num = sg_num;
out_sg = sg;
}
len = n->guest_hdr_len;
ret = qemu_sendv_packet_async(qemu_get_subqueue(n->nic, queue_index),
out_sg, out_num, virtio_net_tx_complete);
if (ret == 0) {
virtio_queue_set_notification(q->tx_vq, 0);
q->async_tx.elem = elem;
q->async_tx.len = len;
return -EBUSY;
}
len += ret;
virtqueue_push(q->tx_vq, &elem, 0);
virtio_notify(&n->vdev, q->tx_vq);
if (++num_packets >= n->tx_burst) {
break;
}
}
return num_packets;
}
static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
VirtIONetQueue *q = &n->vqs[vq2q(virtio_get_queue_index(vq))];
/* This happens when device was stopped but VCPU wasn't. */
if (!n->vdev.vm_running) {
q->tx_waiting = 1;
return;
}
if (q->tx_waiting) {
virtio_queue_set_notification(vq, 1);
qemu_del_timer(q->tx_timer);
q->tx_waiting = 0;
virtio_net_flush_tx(q);
} else {
qemu_mod_timer(q->tx_timer,
qemu_get_clock_ns(vm_clock) + n->tx_timeout);
q->tx_waiting = 1;
virtio_queue_set_notification(vq, 0);
}
}
static void virtio_net_handle_tx_bh(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
VirtIONetQueue *q = &n->vqs[vq2q(virtio_get_queue_index(vq))];
if (unlikely(q->tx_waiting)) {
return;
}
q->tx_waiting = 1;
/* This happens when device was stopped but VCPU wasn't. */
if (!n->vdev.vm_running) {
return;
}
virtio_queue_set_notification(vq, 0);
qemu_bh_schedule(q->tx_bh);
}
static void virtio_net_tx_timer(void *opaque)
{
VirtIONetQueue *q = opaque;
VirtIONet *n = q->n;
assert(n->vdev.vm_running);
q->tx_waiting = 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(q->tx_vq, 1);
virtio_net_flush_tx(q);
}
static void virtio_net_tx_bh(void *opaque)
{
VirtIONetQueue *q = opaque;
VirtIONet *n = q->n;
int32_t ret;
assert(n->vdev.vm_running);
q->tx_waiting = 0;
/* Just in case the driver is not ready on more */
if (unlikely(!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)))
return;
ret = virtio_net_flush_tx(q);
if (ret == -EBUSY) {
return; /* Notification re-enable handled by tx_complete */
}
/* If we flush a full burst of packets, assume there are
* more coming and immediately reschedule */
if (ret >= n->tx_burst) {
qemu_bh_schedule(q->tx_bh);
q->tx_waiting = 1;
return;
}
/* If less than a full burst, re-enable notification and flush
* anything that may have come in while we weren't looking. If
* we find something, assume the guest is still active and reschedule */
virtio_queue_set_notification(q->tx_vq, 1);
if (virtio_net_flush_tx(q) > 0) {
virtio_queue_set_notification(q->tx_vq, 0);
qemu_bh_schedule(q->tx_bh);
q->tx_waiting = 1;
}
}
static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue, int ctrl)
{
VirtIODevice *vdev = &n->vdev;
int i, max = multiqueue ? n->max_queues : 1;
n->multiqueue = multiqueue;
for (i = 2; i <= n->max_queues * 2 + 1; i++) {
virtio_del_queue(vdev, i);
}
for (i = 1; i < max; i++) {
n->vqs[i].rx_vq = virtio_add_queue(vdev, 256, virtio_net_handle_rx);
if (n->vqs[i].tx_timer) {
n->vqs[i].tx_vq =
virtio_add_queue(vdev, 256, virtio_net_handle_tx_timer);
n->vqs[i].tx_timer = qemu_new_timer_ns(vm_clock,
virtio_net_tx_timer,
&n->vqs[i]);
} else {
n->vqs[i].tx_vq =
virtio_add_queue(vdev, 256, virtio_net_handle_tx_bh);
n->vqs[i].tx_bh = qemu_bh_new(virtio_net_tx_bh, &n->vqs[i]);
}
n->vqs[i].tx_waiting = 0;
n->vqs[i].n = n;
}
if (ctrl) {
n->ctrl_vq = virtio_add_queue(vdev, 64, virtio_net_handle_ctrl);
}
virtio_net_set_queues(n);
}
static void virtio_net_save(QEMUFile *f, void *opaque)
{
int i;
VirtIONet *n = opaque;
/* At this point, backend must be stopped, otherwise
* it might keep writing to memory. */
assert(!n->vhost_started);
virtio_save(&n->vdev, f);
qemu_put_buffer(f, n->mac, ETH_ALEN);
qemu_put_be32(f, n->vqs[0].tx_waiting);
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, n->has_vnet_hdr);
qemu_put_byte(f, n->mac_table.multi_overflow);
qemu_put_byte(f, n->mac_table.uni_overflow);
qemu_put_byte(f, n->alluni);
qemu_put_byte(f, n->nomulti);
qemu_put_byte(f, n->nouni);
qemu_put_byte(f, n->nobcast);
qemu_put_byte(f, n->has_ufo);
if (n->max_queues > 1) {
qemu_put_be16(f, n->max_queues);
qemu_put_be16(f, n->curr_queues);
for (i = 1; i < n->curr_queues; i++) {
qemu_put_be32(f, n->vqs[i].tx_waiting);
}
}
}
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
{
VirtIONet *n = opaque;
int ret, i, link_down;
if (version_id < 2 || version_id > VIRTIO_NET_VM_VERSION)
return -EINVAL;
ret = virtio_load(&n->vdev, f);
if (ret) {
return ret;
}
qemu_get_buffer(f, n->mac, ETH_ALEN);
n->vqs[0].tx_waiting = qemu_get_be32(f);
virtio_net_set_mrg_rx_bufs(n, 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) {
uint8_t *buf = g_malloc0(n->mac_table.in_use);
qemu_get_buffer(f, buf, n->mac_table.in_use * ETH_ALEN);
g_free(buf);
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) {
if (qemu_get_be32(f) && !peer_has_vnet_hdr(n)) {
error_report("virtio-net: saved image requires vnet_hdr=on");
return -1;
}
if (n->has_vnet_hdr) {
tap_set_offload(qemu_get_queue(n->nic)->peer,
(n->vdev.guest_features >> VIRTIO_NET_F_GUEST_CSUM) & 1,
(n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO4) & 1,
(n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO6) & 1,
(n->vdev.guest_features >> VIRTIO_NET_F_GUEST_ECN) & 1,
(n->vdev.guest_features >> VIRTIO_NET_F_GUEST_UFO) & 1);
}
}
if (version_id >= 9) {
n->mac_table.multi_overflow = qemu_get_byte(f);
n->mac_table.uni_overflow = qemu_get_byte(f);
}
if (version_id >= 10) {
n->alluni = qemu_get_byte(f);
n->nomulti = qemu_get_byte(f);
n->nouni = qemu_get_byte(f);
n->nobcast = qemu_get_byte(f);
}
if (version_id >= 11) {
if (qemu_get_byte(f) && !peer_has_ufo(n)) {
error_report("virtio-net: saved image requires TUN_F_UFO support");
return -1;
}
}
if (n->max_queues > 1) {
if (n->max_queues != qemu_get_be16(f)) {
error_report("virtio-net: different max_queues ");
return -1;
}
n->curr_queues = qemu_get_be16(f);
for (i = 1; i < n->curr_queues; i++) {
n->vqs[i].tx_waiting = qemu_get_be32(f);
}
}
virtio_net_set_queues(n);
/* Find the first multicast entry in the saved MAC filter */
for (i = 0; i < n->mac_table.in_use; i++) {
if (n->mac_table.macs[i * ETH_ALEN] & 1) {
break;
}
}
n->mac_table.first_multi = i;
/* nc.link_down can't be migrated, so infer link_down according
* to link status bit in n->status */
link_down = (n->status & VIRTIO_NET_S_LINK_UP) == 0;
for (i = 0; i < n->max_queues; i++) {
qemu_get_subqueue(n->nic, i)->link_down = link_down;
}
return 0;
}
static void virtio_net_cleanup(NetClientState *nc)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
n->nic = NULL;
}
static NetClientInfo net_virtio_info = {
.type = NET_CLIENT_OPTIONS_KIND_NIC,
.size = sizeof(NICState),
.can_receive = virtio_net_can_receive,
.receive = virtio_net_receive,
.cleanup = virtio_net_cleanup,
.link_status_changed = virtio_net_set_link_status,
};
static bool virtio_net_guest_notifier_pending(VirtIODevice *vdev, int idx)
{
VirtIONet *n = to_virtio_net(vdev);
NetClientState *nc = qemu_get_subqueue(n->nic, vq2q(idx));
assert(n->vhost_started);
return vhost_net_virtqueue_pending(tap_get_vhost_net(nc->peer), idx);
}
static void virtio_net_guest_notifier_mask(VirtIODevice *vdev, int idx,
bool mask)
{
VirtIONet *n = to_virtio_net(vdev);
NetClientState *nc = qemu_get_subqueue(n->nic, vq2q(idx));
assert(n->vhost_started);
vhost_net_virtqueue_mask(tap_get_vhost_net(nc->peer),
vdev, idx, mask);
}
VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
virtio_net_conf *net, uint32_t host_features)
{
VirtIONet *n;
int i, config_size = 0;
for (i = 0; feature_sizes[i].flags != 0; i++) {
if (host_features & feature_sizes[i].flags) {
config_size = MAX(feature_sizes[i].end, config_size);
}
}
n = (VirtIONet *)virtio_common_init("virtio-net", VIRTIO_ID_NET,
config_size, sizeof(VirtIONet));
n->config_size = config_size;
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->vdev.set_status = virtio_net_set_status;
n->vdev.guest_notifier_mask = virtio_net_guest_notifier_mask;
n->vdev.guest_notifier_pending = virtio_net_guest_notifier_pending;
n->max_queues = MAX(conf->queues, 1);
n->vqs = g_malloc0(sizeof(VirtIONetQueue) * n->max_queues);
n->vqs[0].rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
n->curr_queues = 1;
n->vqs[0].n = n;
n->tx_timeout = net->txtimer;
if (net->tx && strcmp(net->tx, "timer") && strcmp(net->tx, "bh")) {
error_report("virtio-net: "
"Unknown option tx=%s, valid options: \"timer\" \"bh\"",
net->tx);
error_report("Defaulting to \"bh\"");
}
if (net->tx && !strcmp(net->tx, "timer")) {
n->vqs[0].tx_vq = virtio_add_queue(&n->vdev, 256,
virtio_net_handle_tx_timer);
n->vqs[0].tx_timer = qemu_new_timer_ns(vm_clock, virtio_net_tx_timer,
&n->vqs[0]);
} else {
n->vqs[0].tx_vq = virtio_add_queue(&n->vdev, 256,
virtio_net_handle_tx_bh);
n->vqs[0].tx_bh = qemu_bh_new(virtio_net_tx_bh, &n->vqs[0]);
}
n->ctrl_vq = virtio_add_queue(&n->vdev, 64, virtio_net_handle_ctrl);
qemu_macaddr_default_if_unset(&conf->macaddr);
memcpy(&n->mac[0], &conf->macaddr, sizeof(n->mac));
n->status = VIRTIO_NET_S_LINK_UP;
n->nic = qemu_new_nic(&net_virtio_info, conf, object_get_typename(OBJECT(dev)), dev->id, n);
peer_test_vnet_hdr(n);
if (peer_has_vnet_hdr(n)) {
for (i = 0; i < n->max_queues; i++) {
tap_using_vnet_hdr(qemu_get_subqueue(n->nic, i)->peer, true);
}
n->host_hdr_len = sizeof(struct virtio_net_hdr);
} else {
n->host_hdr_len = 0;
}
qemu_format_nic_info_str(qemu_get_queue(n->nic), conf->macaddr.a);
n->vqs[0].tx_waiting = 0;
n->tx_burst = net->txburst;
virtio_net_set_mrg_rx_bufs(n, 0);
n->promisc = 1; /* for compatibility */
n->mac_table.macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN);
n->vlans = g_malloc0(MAX_VLAN >> 3);
n->qdev = dev;
register_savevm(dev, "virtio-net", -1, VIRTIO_NET_VM_VERSION,
virtio_net_save, virtio_net_load, n);
add_boot_device_path(conf->bootindex, dev, "/ethernet-phy@0");
return &n->vdev;
}
void virtio_net_exit(VirtIODevice *vdev)
{
VirtIONet *n = DO_UPCAST(VirtIONet, vdev, vdev);
int i;
/* This will stop vhost backend if appropriate. */
virtio_net_set_status(vdev, 0);
unregister_savevm(n->qdev, "virtio-net", n);
g_free(n->mac_table.macs);
g_free(n->vlans);
for (i = 0; i < n->max_queues; i++) {
VirtIONetQueue *q = &n->vqs[i];
NetClientState *nc = qemu_get_subqueue(n->nic, i);
qemu_purge_queued_packets(nc);
if (q->tx_timer) {
qemu_del_timer(q->tx_timer);
qemu_free_timer(q->tx_timer);
} else {
qemu_bh_delete(q->tx_bh);
}
}
g_free(n->vqs);
qemu_del_nic(n->nic);
virtio_cleanup(&n->vdev);
}