qemu/net/tap.c
Li Qiang ab79237a15 net: tap: use qemu_set_nonblock
The fcntl will change the flags directly, use qemu_set_nonblock()
instead.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Li Qiang <liq3ea@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2019-03-29 15:22:18 +08:00

987 lines
27 KiB
C

/*
* QEMU System Emulator
*
* Copyright (c) 2003-2008 Fabrice Bellard
* Copyright (c) 2009 Red Hat, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "tap_int.h"
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <net/if.h>
#include "net/net.h"
#include "clients.h"
#include "monitor/monitor.h"
#include "sysemu/sysemu.h"
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/cutils.h"
#include "qemu/error-report.h"
#include "qemu/sockets.h"
#include "net/tap.h"
#include "net/vhost_net.h"
typedef struct TAPState {
NetClientState nc;
int fd;
char down_script[1024];
char down_script_arg[128];
uint8_t buf[NET_BUFSIZE];
bool read_poll;
bool write_poll;
bool using_vnet_hdr;
bool has_ufo;
bool enabled;
VHostNetState *vhost_net;
unsigned host_vnet_hdr_len;
Notifier exit;
} TAPState;
static void launch_script(const char *setup_script, const char *ifname,
int fd, Error **errp);
static void tap_send(void *opaque);
static void tap_writable(void *opaque);
static void tap_update_fd_handler(TAPState *s)
{
qemu_set_fd_handler(s->fd,
s->read_poll && s->enabled ? tap_send : NULL,
s->write_poll && s->enabled ? tap_writable : NULL,
s);
}
static void tap_read_poll(TAPState *s, bool enable)
{
s->read_poll = enable;
tap_update_fd_handler(s);
}
static void tap_write_poll(TAPState *s, bool enable)
{
s->write_poll = enable;
tap_update_fd_handler(s);
}
static void tap_writable(void *opaque)
{
TAPState *s = opaque;
tap_write_poll(s, false);
qemu_flush_queued_packets(&s->nc);
}
static ssize_t tap_write_packet(TAPState *s, const struct iovec *iov, int iovcnt)
{
ssize_t len;
do {
len = writev(s->fd, iov, iovcnt);
} while (len == -1 && errno == EINTR);
if (len == -1 && errno == EAGAIN) {
tap_write_poll(s, true);
return 0;
}
return len;
}
static ssize_t tap_receive_iov(NetClientState *nc, const struct iovec *iov,
int iovcnt)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
const struct iovec *iovp = iov;
struct iovec iov_copy[iovcnt + 1];
struct virtio_net_hdr_mrg_rxbuf hdr = { };
if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
iov_copy[0].iov_base = &hdr;
iov_copy[0].iov_len = s->host_vnet_hdr_len;
memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov));
iovp = iov_copy;
iovcnt++;
}
return tap_write_packet(s, iovp, iovcnt);
}
static ssize_t tap_receive_raw(NetClientState *nc, const uint8_t *buf, size_t size)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
struct iovec iov[2];
int iovcnt = 0;
struct virtio_net_hdr_mrg_rxbuf hdr = { };
if (s->host_vnet_hdr_len) {
iov[iovcnt].iov_base = &hdr;
iov[iovcnt].iov_len = s->host_vnet_hdr_len;
iovcnt++;
}
iov[iovcnt].iov_base = (char *)buf;
iov[iovcnt].iov_len = size;
iovcnt++;
return tap_write_packet(s, iov, iovcnt);
}
static ssize_t tap_receive(NetClientState *nc, const uint8_t *buf, size_t size)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
struct iovec iov[1];
if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
return tap_receive_raw(nc, buf, size);
}
iov[0].iov_base = (char *)buf;
iov[0].iov_len = size;
return tap_write_packet(s, iov, 1);
}
#ifndef __sun__
ssize_t tap_read_packet(int tapfd, uint8_t *buf, int maxlen)
{
return read(tapfd, buf, maxlen);
}
#endif
static void tap_send_completed(NetClientState *nc, ssize_t len)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
tap_read_poll(s, true);
}
static void tap_send(void *opaque)
{
TAPState *s = opaque;
int size;
int packets = 0;
while (true) {
uint8_t *buf = s->buf;
size = tap_read_packet(s->fd, s->buf, sizeof(s->buf));
if (size <= 0) {
break;
}
if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
buf += s->host_vnet_hdr_len;
size -= s->host_vnet_hdr_len;
}
size = qemu_send_packet_async(&s->nc, buf, size, tap_send_completed);
if (size == 0) {
tap_read_poll(s, false);
break;
} else if (size < 0) {
break;
}
/*
* When the host keeps receiving more packets while tap_send() is
* running we can hog the QEMU global mutex. Limit the number of
* packets that are processed per tap_send() callback to prevent
* stalling the guest.
*/
packets++;
if (packets >= 50) {
break;
}
}
}
static bool tap_has_ufo(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
return s->has_ufo;
}
static bool tap_has_vnet_hdr(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
return !!s->host_vnet_hdr_len;
}
static bool tap_has_vnet_hdr_len(NetClientState *nc, int len)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
return !!tap_probe_vnet_hdr_len(s->fd, len);
}
static void tap_set_vnet_hdr_len(NetClientState *nc, int len)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
assert(len == sizeof(struct virtio_net_hdr_mrg_rxbuf) ||
len == sizeof(struct virtio_net_hdr));
tap_fd_set_vnet_hdr_len(s->fd, len);
s->host_vnet_hdr_len = len;
}
static void tap_using_vnet_hdr(NetClientState *nc, bool using_vnet_hdr)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
assert(!!s->host_vnet_hdr_len == using_vnet_hdr);
s->using_vnet_hdr = using_vnet_hdr;
}
static int tap_set_vnet_le(NetClientState *nc, bool is_le)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
return tap_fd_set_vnet_le(s->fd, is_le);
}
static int tap_set_vnet_be(NetClientState *nc, bool is_be)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
return tap_fd_set_vnet_be(s->fd, is_be);
}
static void tap_set_offload(NetClientState *nc, int csum, int tso4,
int tso6, int ecn, int ufo)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
if (s->fd < 0) {
return;
}
tap_fd_set_offload(s->fd, csum, tso4, tso6, ecn, ufo);
}
static void tap_exit_notify(Notifier *notifier, void *data)
{
TAPState *s = container_of(notifier, TAPState, exit);
Error *err = NULL;
if (s->down_script[0]) {
launch_script(s->down_script, s->down_script_arg, s->fd, &err);
if (err) {
error_report_err(err);
}
}
}
static void tap_cleanup(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
if (s->vhost_net) {
vhost_net_cleanup(s->vhost_net);
g_free(s->vhost_net);
s->vhost_net = NULL;
}
qemu_purge_queued_packets(nc);
tap_exit_notify(&s->exit, NULL);
qemu_remove_exit_notifier(&s->exit);
tap_read_poll(s, false);
tap_write_poll(s, false);
close(s->fd);
s->fd = -1;
}
static void tap_poll(NetClientState *nc, bool enable)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
tap_read_poll(s, enable);
tap_write_poll(s, enable);
}
int tap_get_fd(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
return s->fd;
}
/* fd support */
static NetClientInfo net_tap_info = {
.type = NET_CLIENT_DRIVER_TAP,
.size = sizeof(TAPState),
.receive = tap_receive,
.receive_raw = tap_receive_raw,
.receive_iov = tap_receive_iov,
.poll = tap_poll,
.cleanup = tap_cleanup,
.has_ufo = tap_has_ufo,
.has_vnet_hdr = tap_has_vnet_hdr,
.has_vnet_hdr_len = tap_has_vnet_hdr_len,
.using_vnet_hdr = tap_using_vnet_hdr,
.set_offload = tap_set_offload,
.set_vnet_hdr_len = tap_set_vnet_hdr_len,
.set_vnet_le = tap_set_vnet_le,
.set_vnet_be = tap_set_vnet_be,
};
static TAPState *net_tap_fd_init(NetClientState *peer,
const char *model,
const char *name,
int fd,
int vnet_hdr)
{
NetClientState *nc;
TAPState *s;
nc = qemu_new_net_client(&net_tap_info, peer, model, name);
s = DO_UPCAST(TAPState, nc, nc);
s->fd = fd;
s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0;
s->using_vnet_hdr = false;
s->has_ufo = tap_probe_has_ufo(s->fd);
s->enabled = true;
tap_set_offload(&s->nc, 0, 0, 0, 0, 0);
/*
* Make sure host header length is set correctly in tap:
* it might have been modified by another instance of qemu.
*/
if (tap_probe_vnet_hdr_len(s->fd, s->host_vnet_hdr_len)) {
tap_fd_set_vnet_hdr_len(s->fd, s->host_vnet_hdr_len);
}
tap_read_poll(s, true);
s->vhost_net = NULL;
s->exit.notify = tap_exit_notify;
qemu_add_exit_notifier(&s->exit);
return s;
}
static void launch_script(const char *setup_script, const char *ifname,
int fd, Error **errp)
{
int pid, status;
char *args[3];
char **parg;
/* try to launch network script */
pid = fork();
if (pid < 0) {
error_setg_errno(errp, errno, "could not launch network script %s",
setup_script);
return;
}
if (pid == 0) {
int open_max = sysconf(_SC_OPEN_MAX), i;
for (i = 3; i < open_max; i++) {
if (i != fd) {
close(i);
}
}
parg = args;
*parg++ = (char *)setup_script;
*parg++ = (char *)ifname;
*parg = NULL;
execv(setup_script, args);
_exit(1);
} else {
while (waitpid(pid, &status, 0) != pid) {
/* loop */
}
if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
return;
}
error_setg(errp, "network script %s failed with status %d",
setup_script, status);
}
}
static int recv_fd(int c)
{
int fd;
uint8_t msgbuf[CMSG_SPACE(sizeof(fd))];
struct msghdr msg = {
.msg_control = msgbuf,
.msg_controllen = sizeof(msgbuf),
};
struct cmsghdr *cmsg;
struct iovec iov;
uint8_t req[1];
ssize_t len;
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
cmsg->cmsg_len = CMSG_LEN(sizeof(fd));
msg.msg_controllen = cmsg->cmsg_len;
iov.iov_base = req;
iov.iov_len = sizeof(req);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
len = recvmsg(c, &msg, 0);
if (len > 0) {
memcpy(&fd, CMSG_DATA(cmsg), sizeof(fd));
return fd;
}
return len;
}
static int net_bridge_run_helper(const char *helper, const char *bridge,
Error **errp)
{
sigset_t oldmask, mask;
int pid, status;
char *args[5];
char **parg;
int sv[2];
sigemptyset(&mask);
sigaddset(&mask, SIGCHLD);
sigprocmask(SIG_BLOCK, &mask, &oldmask);
if (socketpair(PF_UNIX, SOCK_STREAM, 0, sv) == -1) {
error_setg_errno(errp, errno, "socketpair() failed");
return -1;
}
/* try to launch bridge helper */
pid = fork();
if (pid < 0) {
error_setg_errno(errp, errno, "Can't fork bridge helper");
return -1;
}
if (pid == 0) {
int open_max = sysconf(_SC_OPEN_MAX), i;
char fd_buf[6+10];
char br_buf[6+IFNAMSIZ] = {0};
char helper_cmd[PATH_MAX + sizeof(fd_buf) + sizeof(br_buf) + 15];
for (i = 3; i < open_max; i++) {
if (i != sv[1]) {
close(i);
}
}
snprintf(fd_buf, sizeof(fd_buf), "%s%d", "--fd=", sv[1]);
if (strrchr(helper, ' ') || strrchr(helper, '\t')) {
/* assume helper is a command */
if (strstr(helper, "--br=") == NULL) {
snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge);
}
snprintf(helper_cmd, sizeof(helper_cmd), "%s %s %s %s",
helper, "--use-vnet", fd_buf, br_buf);
parg = args;
*parg++ = (char *)"sh";
*parg++ = (char *)"-c";
*parg++ = helper_cmd;
*parg++ = NULL;
execv("/bin/sh", args);
} else {
/* assume helper is just the executable path name */
snprintf(br_buf, sizeof(br_buf), "%s%s", "--br=", bridge);
parg = args;
*parg++ = (char *)helper;
*parg++ = (char *)"--use-vnet";
*parg++ = fd_buf;
*parg++ = br_buf;
*parg++ = NULL;
execv(helper, args);
}
_exit(1);
} else {
int fd;
int saved_errno;
close(sv[1]);
do {
fd = recv_fd(sv[0]);
} while (fd == -1 && errno == EINTR);
saved_errno = errno;
close(sv[0]);
while (waitpid(pid, &status, 0) != pid) {
/* loop */
}
sigprocmask(SIG_SETMASK, &oldmask, NULL);
if (fd < 0) {
error_setg_errno(errp, saved_errno,
"failed to recv file descriptor");
return -1;
}
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
error_setg(errp, "bridge helper failed");
return -1;
}
return fd;
}
}
int net_init_bridge(const Netdev *netdev, const char *name,
NetClientState *peer, Error **errp)
{
const NetdevBridgeOptions *bridge;
const char *helper, *br;
TAPState *s;
int fd, vnet_hdr;
assert(netdev->type == NET_CLIENT_DRIVER_BRIDGE);
bridge = &netdev->u.bridge;
helper = bridge->has_helper ? bridge->helper : DEFAULT_BRIDGE_HELPER;
br = bridge->has_br ? bridge->br : DEFAULT_BRIDGE_INTERFACE;
fd = net_bridge_run_helper(helper, br, errp);
if (fd == -1) {
return -1;
}
qemu_set_nonblock(fd);
vnet_hdr = tap_probe_vnet_hdr(fd);
s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr);
snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s,br=%s", helper,
br);
return 0;
}
static int net_tap_init(const NetdevTapOptions *tap, int *vnet_hdr,
const char *setup_script, char *ifname,
size_t ifname_sz, int mq_required, Error **errp)
{
Error *err = NULL;
int fd, vnet_hdr_required;
if (tap->has_vnet_hdr) {
*vnet_hdr = tap->vnet_hdr;
vnet_hdr_required = *vnet_hdr;
} else {
*vnet_hdr = 1;
vnet_hdr_required = 0;
}
TFR(fd = tap_open(ifname, ifname_sz, vnet_hdr, vnet_hdr_required,
mq_required, errp));
if (fd < 0) {
return -1;
}
if (setup_script &&
setup_script[0] != '\0' &&
strcmp(setup_script, "no") != 0) {
launch_script(setup_script, ifname, fd, &err);
if (err) {
error_propagate(errp, err);
close(fd);
return -1;
}
}
return fd;
}
#define MAX_TAP_QUEUES 1024
static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
const char *model, const char *name,
const char *ifname, const char *script,
const char *downscript, const char *vhostfdname,
int vnet_hdr, int fd, Error **errp)
{
Error *err = NULL;
TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr);
int vhostfd;
tap_set_sndbuf(s->fd, tap, &err);
if (err) {
error_propagate(errp, err);
return;
}
if (tap->has_fd || tap->has_fds) {
snprintf(s->nc.info_str, sizeof(s->nc.info_str), "fd=%d", fd);
} else if (tap->has_helper) {
snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s",
tap->helper);
} else {
snprintf(s->nc.info_str, sizeof(s->nc.info_str),
"ifname=%s,script=%s,downscript=%s", ifname, script,
downscript);
if (strcmp(downscript, "no") != 0) {
snprintf(s->down_script, sizeof(s->down_script), "%s", downscript);
snprintf(s->down_script_arg, sizeof(s->down_script_arg),
"%s", ifname);
}
}
if (tap->has_vhost ? tap->vhost :
vhostfdname || (tap->has_vhostforce && tap->vhostforce)) {
VhostNetOptions options;
options.backend_type = VHOST_BACKEND_TYPE_KERNEL;
options.net_backend = &s->nc;
if (tap->has_poll_us) {
options.busyloop_timeout = tap->poll_us;
} else {
options.busyloop_timeout = 0;
}
if (vhostfdname) {
vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err);
if (vhostfd == -1) {
if (tap->has_vhostforce && tap->vhostforce) {
error_propagate(errp, err);
} else {
warn_report_err(err);
}
return;
}
qemu_set_nonblock(vhostfd);
} else {
vhostfd = open("/dev/vhost-net", O_RDWR);
if (vhostfd < 0) {
if (tap->has_vhostforce && tap->vhostforce) {
error_setg_errno(errp, errno,
"tap: open vhost char device failed");
} else {
warn_report("tap: open vhost char device failed: %s",
strerror(errno));
}
return;
}
qemu_set_nonblock(vhostfd);
}
options.opaque = (void *)(uintptr_t)vhostfd;
s->vhost_net = vhost_net_init(&options);
if (!s->vhost_net) {
if (tap->has_vhostforce && tap->vhostforce) {
error_setg(errp, VHOST_NET_INIT_FAILED);
} else {
warn_report(VHOST_NET_INIT_FAILED);
}
return;
}
} else if (vhostfdname) {
error_setg(errp, "vhostfd(s)= is not valid without vhost");
}
}
static int get_fds(char *str, char *fds[], int max)
{
char *ptr = str, *this;
size_t len = strlen(str);
int i = 0;
while (i < max && ptr < str + len) {
this = strchr(ptr, ':');
if (this == NULL) {
fds[i] = g_strdup(ptr);
} else {
fds[i] = g_strndup(ptr, this - ptr);
}
i++;
if (this == NULL) {
break;
} else {
ptr = this + 1;
}
}
return i;
}
int net_init_tap(const Netdev *netdev, const char *name,
NetClientState *peer, Error **errp)
{
const NetdevTapOptions *tap;
int fd, vnet_hdr = 0, i = 0, queues;
/* for the no-fd, no-helper case */
const char *script = NULL; /* suppress wrong "uninit'd use" gcc warning */
const char *downscript = NULL;
Error *err = NULL;
const char *vhostfdname;
char ifname[128];
assert(netdev->type == NET_CLIENT_DRIVER_TAP);
tap = &netdev->u.tap;
queues = tap->has_queues ? tap->queues : 1;
vhostfdname = tap->has_vhostfd ? tap->vhostfd : NULL;
/* QEMU hubs do not support multiqueue tap, in this case peer is set.
* For -netdev, peer is always NULL. */
if (peer && (tap->has_queues || tap->has_fds || tap->has_vhostfds)) {
error_setg(errp, "Multiqueue tap cannot be used with hubs");
return -1;
}
if (tap->has_fd) {
if (tap->has_ifname || tap->has_script || tap->has_downscript ||
tap->has_vnet_hdr || tap->has_helper || tap->has_queues ||
tap->has_fds || tap->has_vhostfds) {
error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, "
"helper=, queues=, fds=, and vhostfds= "
"are invalid with fd=");
return -1;
}
fd = monitor_fd_param(cur_mon, tap->fd, &err);
if (fd == -1) {
error_propagate(errp, err);
return -1;
}
qemu_set_nonblock(fd);
vnet_hdr = tap_probe_vnet_hdr(fd);
net_init_tap_one(tap, peer, "tap", name, NULL,
script, downscript,
vhostfdname, vnet_hdr, fd, &err);
if (err) {
error_propagate(errp, err);
return -1;
}
} else if (tap->has_fds) {
char **fds;
char **vhost_fds;
int nfds = 0, nvhosts = 0;
int ret = 0;
if (tap->has_ifname || tap->has_script || tap->has_downscript ||
tap->has_vnet_hdr || tap->has_helper || tap->has_queues ||
tap->has_vhostfd) {
error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, "
"helper=, queues=, and vhostfd= "
"are invalid with fds=");
return -1;
}
fds = g_new0(char *, MAX_TAP_QUEUES);
vhost_fds = g_new0(char *, MAX_TAP_QUEUES);
nfds = get_fds(tap->fds, fds, MAX_TAP_QUEUES);
if (tap->has_vhostfds) {
nvhosts = get_fds(tap->vhostfds, vhost_fds, MAX_TAP_QUEUES);
if (nfds != nvhosts) {
error_setg(errp, "The number of fds passed does not match "
"the number of vhostfds passed");
ret = -1;
goto free_fail;
}
}
for (i = 0; i < nfds; i++) {
fd = monitor_fd_param(cur_mon, fds[i], &err);
if (fd == -1) {
error_propagate(errp, err);
ret = -1;
goto free_fail;
}
qemu_set_nonblock(fd);
if (i == 0) {
vnet_hdr = tap_probe_vnet_hdr(fd);
} else if (vnet_hdr != tap_probe_vnet_hdr(fd)) {
error_setg(errp,
"vnet_hdr not consistent across given tap fds");
ret = -1;
goto free_fail;
}
net_init_tap_one(tap, peer, "tap", name, ifname,
script, downscript,
tap->has_vhostfds ? vhost_fds[i] : NULL,
vnet_hdr, fd, &err);
if (err) {
error_propagate(errp, err);
ret = -1;
goto free_fail;
}
}
free_fail:
for (i = 0; i < nvhosts; i++) {
g_free(vhost_fds[i]);
}
for (i = 0; i < nfds; i++) {
g_free(fds[i]);
}
g_free(fds);
g_free(vhost_fds);
return ret;
} else if (tap->has_helper) {
if (tap->has_ifname || tap->has_script || tap->has_downscript ||
tap->has_vnet_hdr || tap->has_queues || tap->has_vhostfds) {
error_setg(errp, "ifname=, script=, downscript=, vnet_hdr=, "
"queues=, and vhostfds= are invalid with helper=");
return -1;
}
fd = net_bridge_run_helper(tap->helper,
tap->has_br ?
tap->br : DEFAULT_BRIDGE_INTERFACE,
errp);
if (fd == -1) {
return -1;
}
qemu_set_nonblock(fd);
vnet_hdr = tap_probe_vnet_hdr(fd);
net_init_tap_one(tap, peer, "bridge", name, ifname,
script, downscript, vhostfdname,
vnet_hdr, fd, &err);
if (err) {
error_propagate(errp, err);
close(fd);
return -1;
}
} else {
if (tap->has_vhostfds) {
error_setg(errp, "vhostfds= is invalid if fds= wasn't specified");
return -1;
}
script = tap->has_script ? tap->script : DEFAULT_NETWORK_SCRIPT;
downscript = tap->has_downscript ? tap->downscript :
DEFAULT_NETWORK_DOWN_SCRIPT;
if (tap->has_ifname) {
pstrcpy(ifname, sizeof ifname, tap->ifname);
} else {
ifname[0] = '\0';
}
for (i = 0; i < queues; i++) {
fd = net_tap_init(tap, &vnet_hdr, i >= 1 ? "no" : script,
ifname, sizeof ifname, queues > 1, errp);
if (fd == -1) {
return -1;
}
if (queues > 1 && i == 0 && !tap->has_ifname) {
if (tap_fd_get_ifname(fd, ifname)) {
error_setg(errp, "Fail to get ifname");
close(fd);
return -1;
}
}
net_init_tap_one(tap, peer, "tap", name, ifname,
i >= 1 ? "no" : script,
i >= 1 ? "no" : downscript,
vhostfdname, vnet_hdr, fd, &err);
if (err) {
error_propagate(errp, err);
close(fd);
return -1;
}
}
}
return 0;
}
VHostNetState *tap_get_vhost_net(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
return s->vhost_net;
}
int tap_enable(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
int ret;
if (s->enabled) {
return 0;
} else {
ret = tap_fd_enable(s->fd);
if (ret == 0) {
s->enabled = true;
tap_update_fd_handler(s);
}
return ret;
}
}
int tap_disable(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
int ret;
if (s->enabled == 0) {
return 0;
} else {
ret = tap_fd_disable(s->fd);
if (ret == 0) {
qemu_purge_queued_packets(nc);
s->enabled = false;
tap_update_fd_handler(s);
}
return ret;
}
}