qemu-e2k/net/vhost-user.c

431 lines
11 KiB
C

/*
* vhost-user.c
*
* Copyright (c) 2013 Virtual Open Systems Sarl.
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "clients.h"
#include "net/vhost_net.h"
#include "net/vhost-user.h"
#include "hw/virtio/vhost-user.h"
#include "chardev/char-fe.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-net.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "trace.h"
typedef struct NetVhostUserState {
NetClientState nc;
CharBackend chr; /* only queue index 0 */
VhostUserState *vhost_user;
VHostNetState *vhost_net;
guint watch;
uint64_t acked_features;
bool started;
} NetVhostUserState;
VHostNetState *vhost_user_get_vhost_net(NetClientState *nc)
{
NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
return s->vhost_net;
}
uint64_t vhost_user_get_acked_features(NetClientState *nc)
{
NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
return s->acked_features;
}
static void vhost_user_stop(int queues, NetClientState *ncs[])
{
NetVhostUserState *s;
int i;
for (i = 0; i < queues; i++) {
assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER);
s = DO_UPCAST(NetVhostUserState, nc, ncs[i]);
if (s->vhost_net) {
/* save acked features */
uint64_t features = vhost_net_get_acked_features(s->vhost_net);
if (features) {
s->acked_features = features;
}
vhost_net_cleanup(s->vhost_net);
}
}
}
static int vhost_user_start(int queues, NetClientState *ncs[],
VhostUserState *be)
{
VhostNetOptions options;
struct vhost_net *net = NULL;
NetVhostUserState *s;
int max_queues;
int i;
options.backend_type = VHOST_BACKEND_TYPE_USER;
for (i = 0; i < queues; i++) {
assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER);
s = DO_UPCAST(NetVhostUserState, nc, ncs[i]);
options.net_backend = ncs[i];
options.opaque = be;
options.busyloop_timeout = 0;
net = vhost_net_init(&options);
if (!net) {
error_report("failed to init vhost_net for queue %d", i);
goto err;
}
if (i == 0) {
max_queues = vhost_net_get_max_queues(net);
if (queues > max_queues) {
error_report("you are asking more queues than supported: %d",
max_queues);
goto err;
}
}
if (s->vhost_net) {
vhost_net_cleanup(s->vhost_net);
g_free(s->vhost_net);
}
s->vhost_net = net;
}
return 0;
err:
if (net) {
vhost_net_cleanup(net);
g_free(net);
}
vhost_user_stop(i, ncs);
return -1;
}
static ssize_t vhost_user_receive(NetClientState *nc, const uint8_t *buf,
size_t size)
{
/* In case of RARP (message size is 60) notify backup to send a fake RARP.
This fake RARP will be sent by backend only for guest
without GUEST_ANNOUNCE capability.
*/
if (size == 60) {
NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc);
int r;
static int display_rarp_failure = 1;
char mac_addr[6];
/* extract guest mac address from the RARP message */
memcpy(mac_addr, &buf[6], 6);
r = vhost_net_notify_migration_done(s->vhost_net, mac_addr);
if ((r != 0) && (display_rarp_failure)) {
fprintf(stderr,
"Vhost user backend fails to broadcast fake RARP\n");
fflush(stderr);
display_rarp_failure = 0;
}
}
return size;
}
static void net_vhost_user_cleanup(NetClientState *nc)
{
NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc);
if (s->vhost_net) {
vhost_net_cleanup(s->vhost_net);
g_free(s->vhost_net);
s->vhost_net = NULL;
}
if (nc->queue_index == 0) {
if (s->watch) {
g_source_remove(s->watch);
s->watch = 0;
}
qemu_chr_fe_deinit(&s->chr, true);
if (s->vhost_user) {
vhost_user_cleanup(s->vhost_user);
g_free(s->vhost_user);
s->vhost_user = NULL;
}
}
qemu_purge_queued_packets(nc);
}
static bool vhost_user_has_vnet_hdr(NetClientState *nc)
{
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
return true;
}
static bool vhost_user_has_ufo(NetClientState *nc)
{
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
return true;
}
static NetClientInfo net_vhost_user_info = {
.type = NET_CLIENT_DRIVER_VHOST_USER,
.size = sizeof(NetVhostUserState),
.receive = vhost_user_receive,
.cleanup = net_vhost_user_cleanup,
.has_vnet_hdr = vhost_user_has_vnet_hdr,
.has_ufo = vhost_user_has_ufo,
};
static gboolean net_vhost_user_watch(GIOChannel *chan, GIOCondition cond,
void *opaque)
{
NetVhostUserState *s = opaque;
qemu_chr_fe_disconnect(&s->chr);
return TRUE;
}
static void net_vhost_user_event(void *opaque, int event);
static void chr_closed_bh(void *opaque)
{
const char *name = opaque;
NetClientState *ncs[MAX_QUEUE_NUM];
NetVhostUserState *s;
Error *err = NULL;
int queues;
queues = qemu_find_net_clients_except(name, ncs,
NET_CLIENT_DRIVER_NIC,
MAX_QUEUE_NUM);
assert(queues < MAX_QUEUE_NUM);
s = DO_UPCAST(NetVhostUserState, nc, ncs[0]);
qmp_set_link(name, false, &err);
vhost_user_stop(queues, ncs);
qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, net_vhost_user_event,
NULL, opaque, NULL, true);
if (err) {
error_report_err(err);
}
}
static void net_vhost_user_event(void *opaque, int event)
{
const char *name = opaque;
NetClientState *ncs[MAX_QUEUE_NUM];
NetVhostUserState *s;
Chardev *chr;
Error *err = NULL;
int queues;
queues = qemu_find_net_clients_except(name, ncs,
NET_CLIENT_DRIVER_NIC,
MAX_QUEUE_NUM);
assert(queues < MAX_QUEUE_NUM);
s = DO_UPCAST(NetVhostUserState, nc, ncs[0]);
chr = qemu_chr_fe_get_driver(&s->chr);
trace_vhost_user_event(chr->label, event);
switch (event) {
case CHR_EVENT_OPENED:
if (vhost_user_start(queues, ncs, s->vhost_user) < 0) {
qemu_chr_fe_disconnect(&s->chr);
return;
}
s->watch = qemu_chr_fe_add_watch(&s->chr, G_IO_HUP,
net_vhost_user_watch, s);
qmp_set_link(name, true, &err);
s->started = true;
break;
case CHR_EVENT_CLOSED:
/* a close event may happen during a read/write, but vhost
* code assumes the vhost_dev remains setup, so delay the
* stop & clear to idle.
* FIXME: better handle failure in vhost code, remove bh
*/
if (s->watch) {
AioContext *ctx = qemu_get_current_aio_context();
g_source_remove(s->watch);
s->watch = 0;
qemu_chr_fe_set_handlers(&s->chr, NULL, NULL, NULL, NULL,
NULL, NULL, false);
aio_bh_schedule_oneshot(ctx, chr_closed_bh, opaque);
}
break;
}
if (err) {
error_report_err(err);
}
}
static int net_vhost_user_init(NetClientState *peer, const char *device,
const char *name, Chardev *chr,
int queues)
{
Error *err = NULL;
NetClientState *nc, *nc0 = NULL;
VhostUserState *user = NULL;
NetVhostUserState *s = NULL;
int i;
assert(name);
assert(queues > 0);
user = vhost_user_init();
if (!user) {
error_report("failed to init vhost_user");
goto err;
}
for (i = 0; i < queues; i++) {
nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name);
snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s",
i, chr->label);
nc->queue_index = i;
if (!nc0) {
nc0 = nc;
s = DO_UPCAST(NetVhostUserState, nc, nc);
if (!qemu_chr_fe_init(&s->chr, chr, &err)) {
error_report_err(err);
goto err;
}
user->chr = &s->chr;
}
s = DO_UPCAST(NetVhostUserState, nc, nc);
s->vhost_user = user;
}
s = DO_UPCAST(NetVhostUserState, nc, nc0);
do {
if (qemu_chr_fe_wait_connected(&s->chr, &err) < 0) {
error_report_err(err);
goto err;
}
qemu_chr_fe_set_handlers(&s->chr, NULL, NULL,
net_vhost_user_event, NULL, nc0->name, NULL,
true);
} while (!s->started);
assert(s->vhost_net);
return 0;
err:
if (user) {
vhost_user_cleanup(user);
g_free(user);
if (s) {
s->vhost_user = NULL;
}
}
if (nc0) {
qemu_del_net_client(nc0);
}
return -1;
}
static Chardev *net_vhost_claim_chardev(
const NetdevVhostUserOptions *opts, Error **errp)
{
Chardev *chr = qemu_chr_find(opts->chardev);
if (chr == NULL) {
error_setg(errp, "chardev \"%s\" not found", opts->chardev);
return NULL;
}
if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_RECONNECTABLE)) {
error_setg(errp, "chardev \"%s\" is not reconnectable",
opts->chardev);
return NULL;
}
if (!qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_FD_PASS)) {
error_setg(errp, "chardev \"%s\" does not support FD passing",
opts->chardev);
return NULL;
}
return chr;
}
static int net_vhost_check_net(void *opaque, QemuOpts *opts, Error **errp)
{
const char *name = opaque;
const char *driver, *netdev;
driver = qemu_opt_get(opts, "driver");
netdev = qemu_opt_get(opts, "netdev");
if (!driver || !netdev) {
return 0;
}
if (strcmp(netdev, name) == 0 &&
!g_str_has_prefix(driver, "virtio-net-")) {
error_setg(errp, "vhost-user requires frontend driver virtio-net-*");
return -1;
}
return 0;
}
int net_init_vhost_user(const Netdev *netdev, const char *name,
NetClientState *peer, Error **errp)
{
int queues;
const NetdevVhostUserOptions *vhost_user_opts;
Chardev *chr;
assert(netdev->type == NET_CLIENT_DRIVER_VHOST_USER);
vhost_user_opts = &netdev->u.vhost_user;
chr = net_vhost_claim_chardev(vhost_user_opts, errp);
if (!chr) {
return -1;
}
/* verify net frontend */
if (qemu_opts_foreach(qemu_find_opts("device"), net_vhost_check_net,
(char *)name, errp)) {
return -1;
}
queues = vhost_user_opts->has_queues ? vhost_user_opts->queues : 1;
if (queues < 1 || queues > MAX_QUEUE_NUM) {
error_setg(errp,
"vhost-user number of queues must be in range [1, %d]",
MAX_QUEUE_NUM);
return -1;
}
return net_vhost_user_init(peer, "vhost_user", name, chr, queues);
}