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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/net/tap.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/net/tap.c')
-rw-r--r--qemu/net/tap.c930
1 files changed, 930 insertions, 0 deletions
diff --git a/qemu/net/tap.c b/qemu/net/tap.c
new file mode 100644
index 000000000..bd01590e8
--- /dev/null
+++ b/qemu/net/tap.c
@@ -0,0 +1,930 @@
+/*
+ * 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 "tap_int.h"
+
+#include "config-host.h"
+
+#include <sys/ioctl.h>
+#include <sys/stat.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 "qemu-common.h"
+#include "qemu/error-report.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;
+} 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_OPTIONS_KIND_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_OPTIONS_KIND_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_OPTIONS_KIND_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_OPTIONS_KIND_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_OPTIONS_KIND_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_cleanup(NetClientState *nc)
+{
+ TAPState *s = DO_UPCAST(TAPState, nc, nc);
+ Error *err = NULL;
+
+ if (s->vhost_net) {
+ vhost_net_cleanup(s->vhost_net);
+ s->vhost_net = NULL;
+ }
+
+ qemu_purge_queued_packets(nc);
+
+ if (s->down_script[0]) {
+ launch_script(s->down_script, s->down_script_arg, s->fd, &err);
+ if (err) {
+ error_report_err(err);
+ }
+ }
+
+ 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_OPTIONS_KIND_TAP);
+ return s->fd;
+}
+
+/* fd support */
+
+static NetClientInfo net_tap_info = {
+ .type = NET_CLIENT_OPTIONS_KIND_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;
+ 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 NetClientOptions *opts, const char *name,
+ NetClientState *peer, Error **errp)
+{
+ const NetdevBridgeOptions *bridge;
+ const char *helper, *br;
+ TAPState *s;
+ int fd, vnet_hdr;
+
+ assert(opts->kind == NET_CLIENT_OPTIONS_KIND_BRIDGE);
+ bridge = opts->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;
+ }
+
+ fcntl(fd, F_SETFL, O_NONBLOCK);
+ 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_vhostfd || tap->has_vhostfds) {
+ vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err);
+ if (vhostfd == -1) {
+ error_propagate(errp, err);
+ return;
+ }
+ } else {
+ vhostfd = open("/dev/vhost-net", O_RDWR);
+ if (vhostfd < 0) {
+ error_setg_errno(errp, errno,
+ "tap: open vhost char device failed");
+ return;
+ }
+ }
+ options.opaque = (void *)(uintptr_t)vhostfd;
+
+ s->vhost_net = vhost_net_init(&options);
+ if (!s->vhost_net) {
+ error_setg(errp,
+ "vhost-net requested but could not be initialized");
+ return;
+ }
+ } else if (tap->has_vhostfd || tap->has_vhostfds) {
+ error_setg(errp, "vhostfd= 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 NetClientOptions *opts, 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(opts->kind == NET_CLIENT_OPTIONS_KIND_TAP);
+ tap = opts->tap;
+ queues = tap->has_queues ? tap->queues : 1;
+ vhostfdname = tap->has_vhostfd ? tap->vhostfd : NULL;
+
+ /* QEMU vlans does 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 QEMU vlans");
+ 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;
+ }
+
+ fcntl(fd, F_SETFL, O_NONBLOCK);
+
+ 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[MAX_TAP_QUEUES];
+ char *vhost_fds[MAX_TAP_QUEUES];
+ int nfds, nvhosts;
+
+ 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;
+ }
+
+ 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");
+ return -1;
+ }
+ }
+
+ for (i = 0; i < nfds; i++) {
+ fd = monitor_fd_param(cur_mon, fds[i], &err);
+ if (fd == -1) {
+ error_propagate(errp, err);
+ return -1;
+ }
+
+ fcntl(fd, F_SETFL, O_NONBLOCK);
+
+ 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");
+ return -1;
+ }
+
+ 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);
+ return -1;
+ }
+ }
+ } 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, DEFAULT_BRIDGE_INTERFACE,
+ errp);
+ if (fd == -1) {
+ return -1;
+ }
+
+ fcntl(fd, F_SETFL, O_NONBLOCK);
+ 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_OPTIONS_KIND_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;
+ }
+}