The legacy "-net" option can be quite confusing for the users since most
people do not expect to get a "vlan" hub between their emulated guest
hardware and the host backend. But so far, we are also not able to get
rid of "-net" completely, since it is the only way to configure on-board
NICs that can not be instantiated via "-device" yet. It's also a little
bit shorter to type "-net nic -net tap" instead of "-device xyz,netdev=n1
-netdev tap,id=n1".
So what we need is a new convenience option that is shorter to type than
the full -device + -netdev stuff, and which can be used to configure the
on-board NICs that can not be handled via -device yet. Thus this patch now
provides such a new option "-n": It adds an entry in the nd_table to
configure a on-board / default NIC, creates a host backend and connects
the two directly, without a confusing "vlan" hub inbetween.
Signed-off-by: Thomas Huth <th...@redhat.com>
---
include/sysemu/sysemu.h | 1 +
net/net.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++
qemu-options.hx | 40 +++++++++++++++++++++----
vl.c | 7 +++++
4 files changed, 120 insertions(+), 6 deletions(-)
diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
index 77bb3da..46ec1bf 100644
--- a/include/sysemu/sysemu.h
+++ b/include/sysemu/sysemu.h
@@ -197,6 +197,7 @@ extern QemuOptsList bdrv_runtime_opts;
extern QemuOptsList qemu_chardev_opts;
extern QemuOptsList qemu_device_opts;
extern QemuOptsList qemu_netdev_opts;
+extern QemuOptsList qemu_n_opts;
extern QemuOptsList qemu_net_opts;
extern QemuOptsList qemu_global_opts;
extern QemuOptsList qemu_mon_opts;
diff --git a/net/net.c b/net/net.c
index fe29cfa..ffd52c6 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1457,6 +1457,67 @@ static int net_init_client(void *dummy, QemuOpts *opts,
Error **errp)
return net_client_init(opts, false, errp);
}
+/* For the convenience "-n" parameter */
+static int net_init_n(void *dummy, QemuOpts *opts, Error **errp)
+{
+ char *mac, *nd_id;
+ int idx, ret;
+ NICInfo *ni;
+ const char *type;
+
+ type = qemu_opt_get(opts, "type");
+ if (type && g_str_equal(type, "none")) {
+ return 0; /* Nothing to do, default_net is cleared in vl.c */
+ }
+
+ idx = nic_get_free_idx();
+ if (idx == -1 || nb_nics >= MAX_NICS) {
+ error_setg(errp, "no more on-board/default NIC slots available");
+ return -1;
+ }
+
+ if (!type) {
+ qemu_opt_set(opts, "type", "user", &error_abort);
+ }
+
+ ni = &nd_table[idx];
+ memset(ni, 0, sizeof(*ni));
+ ni->model = qemu_opt_get_del(opts, "model");
+
+ /* Create an ID if the user did not specify one */
+ nd_id = g_strdup(qemu_opts_id(opts));
+ if (!nd_id) {
+ nd_id = g_strdup_printf("__org.qemu.nic%i\n", idx);
+ qemu_opts_set_id(opts, nd_id);
+ }
+
+ /* Handle MAC address */
+ mac = qemu_opt_get_del(opts, "mac");
+ if (mac) {
+ ret = net_parse_macaddr(ni->macaddr.a, mac);
+ g_free(mac);
+ if (ret) {
+ error_setg(errp, "invalid syntax for ethernet address");
+ return -1;
+ }
+ if (is_multicast_ether_addr(ni->macaddr.a)) {
+ error_setg(errp, "NIC cannot have multicast MAC address");
+ return -1;
+ }
+ }
+ qemu_macaddr_default_if_unset(&ni->macaddr);
+
+ ret = net_client_init(opts, true, errp);
+ if (ret == 0) {
+ ni->netdev = qemu_find_netdev(nd_id);
+ ni->used = true;
+ nb_nics++;
+ }
+
+ g_free(nd_id);
+ return ret;
+}
+
static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
{
return net_client_init(opts, true, errp);
@@ -1474,6 +1535,10 @@ int net_init_clients(Error **errp)
return -1;
}
+ if (qemu_opts_foreach(qemu_find_opts("n"), net_init_n, NULL, errp)) {
+ return -1;
+ }
+
if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp))
{
return -1;
}
@@ -1549,6 +1614,19 @@ QemuOptsList qemu_netdev_opts = {
},
};
+QemuOptsList qemu_n_opts = {
+ .name = "n",
+ .implied_opt_name = "type",
+ .head = QTAILQ_HEAD_INITIALIZER(qemu_n_opts.head),
+ .desc = {
+ /*
+ * no elements => accept any params
+ * validation will happen later
+ */
+ { /* end of list */ }
+ },
+};
+
QemuOptsList qemu_net_opts = {
.name = "net",
.implied_opt_name = "type",
diff --git a/qemu-options.hx b/qemu-options.hx
index f6172e5..5e4c64d 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2004,13 +2004,34 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
#endif
"-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
" configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL)
+DEF("n", HAS_ARG, QEMU_OPTION_n,
+ "-n [tap|bridge|"
+#ifdef CONFIG_SLIRP
+ "user|"
+#endif
+#ifdef __linux__
+ "l2tpv3|"
+#endif
+#ifdef CONFIG_VDE
+ "vde|"
+#endif
+#ifdef CONFIG_NETMAP
+ "netmap|"
+#endif
+#ifdef CONFIG_POSIX
+ "vhost-user|"
+#endif
+ "socket][,option][,...][mac=macaddr]\n"
+ " initialize an on-board / default host NIC (using MAC
address\n"
+ " macaddr) and connect it to the given host network
backend\n"
+ "-n none use it alone to have zero network devices (the default is
to\n"
+ " provided a 'user' network connection)\n",
+ QEMU_ARCH_ALL)
DEF("net", HAS_ARG, QEMU_OPTION_net,
"-net
nic[,vlan=n][,netdev=nd][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
" configure or create an on-board (or machine default) NIC
and\n"
" connect it either to VLAN 'n' or the netdev 'nd' (for
pluggable\n"
" NICs please use '-device devtype,netdev=nd' instead)\n"
- "-net none use it alone to have zero network devices. If no -net
option\n"
- " is provided, the default is '-net nic -net user'\n"
"-net ["
#ifdef CONFIG_SLIRP
"user|"
@@ -2456,10 +2477,17 @@ qemu -m 512 -object
memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,sha
-device virtio-net-pci,netdev=net0
@end example
-@item -net none
-Indicate that no network devices should be configured. It is used to
-override the default configuration (@option{-net nic -net user}) which
-is activated if no @option{-net} options are provided.
+@item -n
[tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr]
+
+This option is a shortcut for setting both, the on-board (default) guest NIC
+hardware and the host network backend in one go. The host backend options are
+the same as with the corresponding @option{--netdev} option. The guest NIC
+hardware MAC address can be set with @option{mac=@var{macaddr}}.
+
+@item -n none
+Indicate that no network devices should be configured. It is used to override
+the default configuration (default NIC with @option{--net user} backend) which
+is activated if no other networking options are provided.
ETEXI
STEXI
diff --git a/vl.c b/vl.c
index 7e95711..b84c702 100644
--- a/vl.c
+++ b/vl.c
@@ -3094,6 +3094,7 @@ int main(int argc, char **argv, char **envp)
qemu_add_opts(&qemu_chardev_opts);
qemu_add_opts(&qemu_device_opts);
qemu_add_opts(&qemu_netdev_opts);
+ qemu_add_opts(&qemu_n_opts);
qemu_add_opts(&qemu_net_opts);
qemu_add_opts(&qemu_rtc_opts);
qemu_add_opts(&qemu_global_opts);
@@ -3314,6 +3315,12 @@ int main(int argc, char **argv, char **envp)
exit(1);
}
break;
+ case QEMU_OPTION_n:
+ default_net = 0;
+ if (net_client_parse(qemu_find_opts("n"), optarg) == -1) {
+ exit(1);
+ }
+ break;
case QEMU_OPTION_net:
default_net = 0;
if (net_client_parse(qemu_find_opts("net"), optarg) == -1) {
--
1.8.3.1
