virtio-net: separate virtqueue from VirtIONet

To support multiqueue virtio-net, the first step is to separate the virtqueue
related fields from VirtIONet to a new structure VirtIONetQueue. The following
patches will add an array of VirtIONetQueue to VirtIONet based on this patch.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Jason Wang 2013-01-30 19:12:38 +08:00 committed by Anthony Liguori
parent e78a2b4285
commit 0c87e93e31
1 changed files with 114 additions and 81 deletions

View File

@ -26,28 +26,33 @@
#define MAC_TABLE_ENTRIES 64
#define MAX_VLAN (1 << 12) /* Per 802.1Q definition */
typedef struct VirtIONetQueue {
VirtQueue *rx_vq;
VirtQueue *tx_vq;
QEMUTimer *tx_timer;
QEMUBH *tx_bh;
int tx_waiting;
struct {
VirtQueueElement elem;
ssize_t len;
} async_tx;
struct VirtIONet *n;
} VirtIONetQueue;
typedef struct VirtIONet
{
VirtIODevice vdev;
uint8_t mac[ETH_ALEN];
uint16_t status;
VirtQueue *rx_vq;
VirtQueue *tx_vq;
VirtIONetQueue vq;
VirtQueue *ctrl_vq;
NICState *nic;
QEMUTimer *tx_timer;
QEMUBH *tx_bh;
uint32_t tx_timeout;
int32_t tx_burst;
int tx_waiting;
uint32_t has_vnet_hdr;
size_t host_hdr_len;
size_t guest_hdr_len;
uint8_t has_ufo;
struct {
VirtQueueElement elem;
ssize_t len;
} async_tx;
int mergeable_rx_bufs;
uint8_t promisc;
uint8_t allmulti;
@ -67,6 +72,12 @@ typedef struct VirtIONet
DeviceState *qdev;
} VirtIONet;
static VirtIONetQueue *virtio_net_get_queue(NetClientState *nc)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
return &n->vq;
}
/* TODO
* - we could suppress RX interrupt if we were so inclined.
*/
@ -135,6 +146,8 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
error_report("unable to start vhost net: %d: "
"falling back on userspace virtio", -r);
n->vhost_started = 0;
} else {
n->vhost_started = 1;
}
} else {
vhost_net_stop(&n->vdev, nc, 1);
@ -145,25 +158,26 @@ static void virtio_net_vhost_status(VirtIONet *n, uint8_t status)
static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
{
VirtIONet *n = to_virtio_net(vdev);
VirtIONetQueue *q = &n->vq;
virtio_net_vhost_status(n, status);
if (!n->tx_waiting) {
if (!q->tx_waiting) {
return;
}
if (virtio_net_started(n, status) && !n->vhost_started) {
if (n->tx_timer) {
qemu_mod_timer(n->tx_timer,
if (q->tx_timer) {
qemu_mod_timer(q->tx_timer,
qemu_get_clock_ns(vm_clock) + n->tx_timeout);
} else {
qemu_bh_schedule(n->tx_bh);
qemu_bh_schedule(q->tx_bh);
}
} else {
if (n->tx_timer) {
qemu_del_timer(n->tx_timer);
if (q->tx_timer) {
qemu_del_timer(q->tx_timer);
} else {
qemu_bh_cancel(n->tx_bh);
qemu_bh_cancel(q->tx_bh);
}
}
}
@ -507,35 +521,40 @@ static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq)
static int virtio_net_can_receive(NetClientState *nc)
{
VirtIONet *n = qemu_get_nic_opaque(nc);
VirtIONetQueue *q = virtio_net_get_queue(nc);
if (!n->vdev.vm_running) {
return 0;
}
if (!virtio_queue_ready(n->rx_vq) ||
!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK))
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(VirtIONet *n, int bufsize)
static int virtio_net_has_buffers(VirtIONetQueue *q, int bufsize)
{
if (virtio_queue_empty(n->rx_vq) ||
VirtIONet *n = q->n;
if (virtio_queue_empty(q->rx_vq) ||
(n->mergeable_rx_bufs &&
!virtqueue_avail_bytes(n->rx_vq, bufsize, 0))) {
virtio_queue_set_notification(n->rx_vq, 1);
!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(n->rx_vq) ||
if (virtio_queue_empty(q->rx_vq) ||
(n->mergeable_rx_bufs &&
!virtqueue_avail_bytes(n->rx_vq, bufsize, 0)))
!virtqueue_avail_bytes(q->rx_vq, bufsize, 0))) {
return 0;
}
}
virtio_queue_set_notification(n->rx_vq, 0);
virtio_queue_set_notification(q->rx_vq, 0);
return 1;
}
@ -638,6 +657,7 @@ static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
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_queue(nc);
struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE];
struct virtio_net_hdr_mrg_rxbuf mhdr;
unsigned mhdr_cnt = 0;
@ -648,8 +668,9 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t
}
/* hdr_len refers to the header we supply to the guest */
if (!virtio_net_has_buffers(n, size + n->guest_hdr_len - n->host_hdr_len))
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;
@ -663,7 +684,7 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t
total = 0;
if (virtqueue_pop(n->rx_vq, &elem) == 0) {
if (virtqueue_pop(q->rx_vq, &elem) == 0) {
if (i == 0)
return -1;
error_report("virtio-net unexpected empty queue: "
@ -716,7 +737,7 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t
}
/* signal other side */
virtqueue_fill(n->rx_vq, &elem, total, i++);
virtqueue_fill(q->rx_vq, &elem, total, i++);
}
if (mhdr_cnt) {
@ -726,30 +747,32 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t
&mhdr.num_buffers, sizeof mhdr.num_buffers);
}
virtqueue_flush(n->rx_vq, i);
virtio_notify(&n->vdev, n->rx_vq);
virtqueue_flush(q->rx_vq, i);
virtio_notify(&n->vdev, q->rx_vq);
return size;
}
static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq);
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_queue(nc);
virtqueue_push(n->tx_vq, &n->async_tx.elem, 0);
virtio_notify(&n->vdev, n->tx_vq);
virtqueue_push(q->tx_vq, &q->async_tx.elem, 0);
virtio_notify(&n->vdev, q->tx_vq);
n->async_tx.elem.out_num = n->async_tx.len = 0;
q->async_tx.elem.out_num = q->async_tx.len = 0;
virtio_queue_set_notification(n->tx_vq, 1);
virtio_net_flush_tx(n, n->tx_vq);
virtio_queue_set_notification(q->tx_vq, 1);
virtio_net_flush_tx(q);
}
/* TX */
static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
{
VirtIONet *n = q->n;
VirtQueueElement elem;
int32_t num_packets = 0;
if (!(n->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)) {
@ -758,12 +781,12 @@ static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
assert(n->vdev.vm_running);
if (n->async_tx.elem.out_num) {
virtio_queue_set_notification(n->tx_vq, 0);
if (q->async_tx.elem.out_num) {
virtio_queue_set_notification(q->tx_vq, 0);
return num_packets;
}
while (virtqueue_pop(vq, &elem)) {
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];
@ -796,16 +819,16 @@ static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
ret = qemu_sendv_packet_async(qemu_get_queue(n->nic), out_sg, out_num,
virtio_net_tx_complete);
if (ret == 0) {
virtio_queue_set_notification(n->tx_vq, 0);
n->async_tx.elem = elem;
n->async_tx.len = len;
virtio_queue_set_notification(q->tx_vq, 0);
q->async_tx.elem = elem;
q->async_tx.len = len;
return -EBUSY;
}
len += ret;
virtqueue_push(vq, &elem, 0);
virtio_notify(&n->vdev, vq);
virtqueue_push(q->tx_vq, &elem, 0);
virtio_notify(&n->vdev, q->tx_vq);
if (++num_packets >= n->tx_burst) {
break;
@ -817,22 +840,23 @@ static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
VirtIONetQueue *q = &n->vq;
/* This happens when device was stopped but VCPU wasn't. */
if (!n->vdev.vm_running) {
n->tx_waiting = 1;
q->tx_waiting = 1;
return;
}
if (n->tx_waiting) {
if (q->tx_waiting) {
virtio_queue_set_notification(vq, 1);
qemu_del_timer(n->tx_timer);
n->tx_waiting = 0;
virtio_net_flush_tx(n, vq);
qemu_del_timer(q->tx_timer);
q->tx_waiting = 0;
virtio_net_flush_tx(q);
} else {
qemu_mod_timer(n->tx_timer,
qemu_mod_timer(q->tx_timer,
qemu_get_clock_ns(vm_clock) + n->tx_timeout);
n->tx_waiting = 1;
q->tx_waiting = 1;
virtio_queue_set_notification(vq, 0);
}
}
@ -840,48 +864,51 @@ static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
static void virtio_net_handle_tx_bh(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = to_virtio_net(vdev);
VirtIONetQueue *q = &n->vq;
if (unlikely(n->tx_waiting)) {
if (unlikely(q->tx_waiting)) {
return;
}
n->tx_waiting = 1;
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(n->tx_bh);
qemu_bh_schedule(q->tx_bh);
}
static void virtio_net_tx_timer(void *opaque)
{
VirtIONet *n = opaque;
VirtIONetQueue *q = opaque;
VirtIONet *n = q->n;
assert(n->vdev.vm_running);
n->tx_waiting = 0;
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(n->tx_vq, 1);
virtio_net_flush_tx(n, n->tx_vq);
virtio_queue_set_notification(q->tx_vq, 1);
virtio_net_flush_tx(q);
}
static void virtio_net_tx_bh(void *opaque)
{
VirtIONet *n = opaque;
VirtIONetQueue *q = opaque;
VirtIONet *n = q->n;
int32_t ret;
assert(n->vdev.vm_running);
n->tx_waiting = 0;
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(n, n->tx_vq);
ret = virtio_net_flush_tx(q);
if (ret == -EBUSY) {
return; /* Notification re-enable handled by tx_complete */
}
@ -889,25 +916,26 @@ static void virtio_net_tx_bh(void *opaque)
/* If we flush a full burst of packets, assume there are
* more coming and immediately reschedule */
if (ret >= n->tx_burst) {
qemu_bh_schedule(n->tx_bh);
n->tx_waiting = 1;
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(n->tx_vq, 1);
if (virtio_net_flush_tx(n, n->tx_vq) > 0) {
virtio_queue_set_notification(n->tx_vq, 0);
qemu_bh_schedule(n->tx_bh);
n->tx_waiting = 1;
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_save(QEMUFile *f, void *opaque)
{
VirtIONet *n = opaque;
VirtIONetQueue *q = &n->vq;
/* At this point, backend must be stopped, otherwise
* it might keep writing to memory. */
@ -915,7 +943,7 @@ static void virtio_net_save(QEMUFile *f, void *opaque)
virtio_save(&n->vdev, f);
qemu_put_buffer(f, n->mac, ETH_ALEN);
qemu_put_be32(f, n->tx_waiting);
qemu_put_be32(f, q->tx_waiting);
qemu_put_be32(f, n->mergeable_rx_bufs);
qemu_put_be16(f, n->status);
qemu_put_byte(f, n->promisc);
@ -936,6 +964,7 @@ static void virtio_net_save(QEMUFile *f, void *opaque)
static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
{
VirtIONet *n = opaque;
VirtIONetQueue *q = &n->vq;
int i;
int ret;
@ -948,7 +977,7 @@ static int virtio_net_load(QEMUFile *f, void *opaque, int version_id)
}
qemu_get_buffer(f, n->mac, ETH_ALEN);
n->tx_waiting = qemu_get_be32(f);
q->tx_waiting = qemu_get_be32(f);
virtio_net_set_mrg_rx_bufs(n, qemu_get_be32(f));
@ -1085,7 +1114,8 @@ VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
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->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
n->vq.rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx);
n->vq.n = n;
if (net->tx && strcmp(net->tx, "timer") && strcmp(net->tx, "bh")) {
error_report("virtio-net: "
@ -1095,12 +1125,14 @@ VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
}
if (net->tx && !strcmp(net->tx, "timer")) {
n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx_timer);
n->tx_timer = qemu_new_timer_ns(vm_clock, virtio_net_tx_timer, n);
n->vq.tx_vq = virtio_add_queue(&n->vdev, 256,
virtio_net_handle_tx_timer);
n->vq.tx_timer = qemu_new_timer_ns(vm_clock,
virtio_net_tx_timer, &n->vq);
n->tx_timeout = net->txtimer;
} else {
n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx_bh);
n->tx_bh = qemu_bh_new(virtio_net_tx_bh, n);
n->vq.tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx_bh);
n->vq.tx_bh = qemu_bh_new(virtio_net_tx_bh, &n->vq);
}
n->ctrl_vq = virtio_add_queue(&n->vdev, 64, virtio_net_handle_ctrl);
qemu_macaddr_default_if_unset(&conf->macaddr);
@ -1118,7 +1150,7 @@ VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
qemu_format_nic_info_str(qemu_get_queue(n->nic), conf->macaddr.a);
n->tx_waiting = 0;
n->vq.tx_waiting = 0;
n->tx_burst = net->txburst;
virtio_net_set_mrg_rx_bufs(n, 0);
n->promisc = 1; /* for compatibility */
@ -1139,6 +1171,7 @@ VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
void virtio_net_exit(VirtIODevice *vdev)
{
VirtIONet *n = DO_UPCAST(VirtIONet, vdev, vdev);
VirtIONetQueue *q = &n->vq;
/* This will stop vhost backend if appropriate. */
virtio_net_set_status(vdev, 0);
@ -1150,11 +1183,11 @@ void virtio_net_exit(VirtIODevice *vdev)
g_free(n->mac_table.macs);
g_free(n->vlans);
if (n->tx_timer) {
qemu_del_timer(n->tx_timer);
qemu_free_timer(n->tx_timer);
if (q->tx_timer) {
qemu_del_timer(q->tx_timer);
qemu_free_timer(q->tx_timer);
} else {
qemu_bh_delete(n->tx_bh);
qemu_bh_delete(q->tx_bh);
}
qemu_del_nic(n->nic);