Commit 78cd6f7b authored by Thomas Huth's avatar Thomas Huth Committed by Jason Wang
Browse files

net: Add a new convenience option "--nic" to configure default/on-board NICs 



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 "--nic": 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.

Reviewed-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: default avatarThomas Huth <thuth@redhat.com>
Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
parent 7cc28cb0

include/sysemu/sysemu.h

+1 −0
Original line number Diff line number Diff line
@@ -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_nic_opts;

extern QemuOptsList qemu_net_opts;

extern QemuOptsList qemu_global_opts;

extern QemuOptsList qemu_mon_opts;

net/net.c

+78 −0
Original line number Diff line number Diff line
@@ -1462,6 +1462,67 @@ static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp) 
    return net_client_init(opts, true, errp);

}



/* For the convenience "--nic" parameter */

static int net_param_nic(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;

}



int net_init_clients(Error **errp)

{

    net_change_state_entry =
@@ -1474,6 +1535,10 @@ int net_init_clients(Error **errp) 
        return -1;

    }



    if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, 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_nic_opts = {

    .name = "nic",

    .implied_opt_name = "type",

    .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_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",

qemu-options.hx

+34 −6
Original line number Diff line number Diff line
@@ -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("nic", HAS_ARG, QEMU_OPTION_nic,

    "--nic [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"

    "--nic 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 --nic [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 --nic 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

vl.c

+7 −0
Original line number Diff line number Diff line
@@ -3091,6 +3091,7 @@ 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_nic_opts);

    qemu_add_opts(&qemu_net_opts);

    qemu_add_opts(&qemu_rtc_opts);

    qemu_add_opts(&qemu_global_opts);
@@ -3311,6 +3312,12 @@ int main(int argc, char **argv, char **envp) 
                    exit(1);

                }

                break;

            case QEMU_OPTION_nic:

                default_net = 0;

                if (net_client_parse(qemu_find_opts("nic"), optarg) == -1) {

                    exit(1);

                }

                break;

            case QEMU_OPTION_net:

                default_net = 0;

                if (net_client_parse(qemu_find_opts("net"), optarg) == -1) {