Eric Blake <ebl...@redhat.com> wrote:
> You also need to add a line documenting this field:
>
> # @ifname: #optional Set the interface name that will be used (since
> 1.5).
Done. I also added an example with -netdev and -device
(seems this question is not covered in docs).
Signed-off-by: Alexandre Kandalintsev <s...@messir.net>
---
include/net/net.h | 1 +
net/tap.c | 25 ++++++++++++++++---------
qapi-schema.json | 1 +
qemu-bridge-helper.c | 12 ++++++++++--
qemu-options.hx | 18 ++++++++++++++++--
5 files changed, 44 insertions(+), 13 deletions(-)
diff --git a/include/net/net.h b/include/net/net.h
index cb049a1..4b25eb5 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -172,6 +172,7 @@ NetClientState *net_hub_port_find(int hub_id);
#define DEFAULT_NETWORK_DOWN_SCRIPT "/etc/qemu-ifdown"
#define DEFAULT_BRIDGE_HELPER CONFIG_QEMU_HELPERDIR "/qemu-bridge-helper"
#define DEFAULT_BRIDGE_INTERFACE "br0"
+#define DEFAULT_BRIDGE_IFNAME "tap%d"
void qdev_set_nic_properties(DeviceState *dev, NICInfo *nd);
diff --git a/net/tap.c b/net/tap.c
index ce79699..d1d5b6a 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -424,11 +424,11 @@ static int recv_fd(int c)
return len;
}
-static int net_bridge_run_helper(const char *helper, const char *bridge)
+static int net_bridge_run_helper(const char *helper, const char *bridge, const
char *ifname)
{
sigset_t oldmask, mask;
int pid, status;
- char *args[5];
+ char *args[6];
char **parg;
int sv[2];
@@ -446,6 +446,7 @@ static int net_bridge_run_helper(const char *helper, const
char *bridge)
int open_max = sysconf(_SC_OPEN_MAX), i;
char fd_buf[6+10];
char br_buf[6+IFNAMSIZ] = {0};
+ char ifname_buf[9+IFNAMSIZ] = {0};
char helper_cmd[PATH_MAX + sizeof(fd_buf) + sizeof(br_buf) + 15];
for (i = 0; i < open_max; i++) {
@@ -459,6 +460,10 @@ static int net_bridge_run_helper(const char *helper, const
char *bridge)
snprintf(fd_buf, sizeof(fd_buf), "%s%d", "--fd=", sv[1]);
+ if (ifname) {
+ snprintf(ifname_buf, sizeof(ifname_buf), "%s%s", "--ifname=",
ifname);
+ }
+
if (strrchr(helper, ' ') || strrchr(helper, '\t')) {
/* assume helper is a command */
@@ -466,8 +471,8 @@ static int net_bridge_run_helper(const char *helper, const
char *bridge)
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);
+ snprintf(helper_cmd, sizeof(helper_cmd), "%s %s %s %s %s",
+ helper, "--use-vnet", fd_buf, br_buf, ifname_buf);
parg = args;
*parg++ = (char *)"sh";
@@ -486,6 +491,7 @@ static int net_bridge_run_helper(const char *helper, const
char *bridge)
*parg++ = (char *)"--use-vnet";
*parg++ = fd_buf;
*parg++ = br_buf;
+ *parg++ = ifname_buf;
*parg++ = NULL;
execv(helper, args);
@@ -524,7 +530,7 @@ int net_init_bridge(const NetClientOptions *opts, const
char *name,
NetClientState *peer)
{
const NetdevBridgeOptions *bridge;
- const char *helper, *br;
+ const char *helper, *br, *ifname;
TAPState *s;
int fd, vnet_hdr;
@@ -534,8 +540,9 @@ int net_init_bridge(const NetClientOptions *opts, const
char *name,
helper = bridge->has_helper ? bridge->helper : DEFAULT_BRIDGE_HELPER;
br = bridge->has_br ? bridge->br : DEFAULT_BRIDGE_INTERFACE;
+ ifname = bridge->has_ifname ? bridge->ifname : DEFAULT_BRIDGE_IFNAME;
- fd = net_bridge_run_helper(helper, br);
+ fd = net_bridge_run_helper(helper, br, ifname);
if (fd == -1) {
return -1;
}
@@ -686,11 +693,12 @@ int net_init_tap(const NetClientOptions *opts, const char
*name,
const char *script = NULL; /* suppress wrong "uninit'd use" gcc warning */
const char *downscript = NULL;
const char *vhostfdname;
+ const char *br;
char ifname[128];
assert(opts->kind == NET_CLIENT_OPTIONS_KIND_TAP);
tap = opts->tap;
- queues = tap->has_queues ? tap->queues : 1;
+ 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.
@@ -775,8 +783,7 @@ int net_init_tap(const NetClientOptions *opts, const char
*name,
"queues=, and fds= are invalid with helper=");
return -1;
}
-
- fd = net_bridge_run_helper(tap->helper, DEFAULT_BRIDGE_INTERFACE);
+ fd = net_bridge_run_helper(tap->helper, DEFAULT_BRIDGE_INTERFACE,
NULL);
if (fd == -1) {
return -1;
}
diff --git a/qapi-schema.json b/qapi-schema.json
index 088f4e1..be2373a 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2676,6 +2676,7 @@
{ 'type': 'NetdevBridgeOptions',
'data': {
'*br': 'str',
+ '*ifname': 'str',
'*helper': 'str' } }
##
diff --git a/qemu-bridge-helper.c b/qemu-bridge-helper.c
index 287bfd5..39486b1 100644
--- a/qemu-bridge-helper.c
+++ b/qemu-bridge-helper.c
@@ -67,7 +67,7 @@ typedef QSIMPLEQ_HEAD(ACLList, ACLRule) ACLList;
static void usage(void)
{
fprintf(stderr,
- "Usage: qemu-bridge-helper [--use-vnet] --br=bridge
--fd=unixfd\n");
+ "Usage: qemu-bridge-helper [--use-vnet] [--ifname=name]
--br=bridge --fd=unixfd\n");
}
static int parse_acl_file(const char *filename, ACLList *acl_list)
@@ -233,6 +233,7 @@ int main(int argc, char **argv)
int use_vnet = 0;
int mtu;
const char *bridge = NULL;
+ const char *ifname = NULL;
char iface[IFNAMSIZ];
int index;
ACLRule *acl_rule;
@@ -259,6 +260,8 @@ int main(int argc, char **argv)
bridge = &argv[index][5];
} else if (strncmp(argv[index], "--fd=", 5) == 0) {
unixfd = atoi(&argv[index][5]);
+ } else if (strncmp(argv[index], "--ifname=", 9) == 0) {
+ ifname = &argv[index][9];
} else {
usage();
return EXIT_FAILURE;
@@ -330,7 +333,12 @@ int main(int argc, char **argv)
/* request a tap device, disable PI, and add vnet header support if
* requested and it's available. */
- prep_ifreq(&ifr, "tap%d");
+ if (ifname) {
+ /* prep_ifreq will truncate the name if it is too long */
+ prep_ifreq(&ifr, ifname);
+ } else {
+ prep_ifreq(&ifr, "tap%d");
+ }
ifr.ifr_flags = IFF_TAP|IFF_NO_PI;
if (use_vnet && has_vnet_hdr(fd)) {
ifr.ifr_flags |= IFF_VNET_HDR;
diff --git a/qemu-options.hx b/qemu-options.hx
index d7afeab..dd49c6c 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -1379,7 +1379,7 @@ DEF("net", HAS_ARG, QEMU_OPTION_net,
" use vhostforce=on to force vhost on for non-MSIX virtio
guests\n"
" use 'vhostfd=h' to connect to an already opened vhost net
device\n"
" use 'vhostfds=x:y:...:z to connect to multiple already
opened vhost net devices\n"
- "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
+ "-net
bridge[,vlan=n][,name=str][,br=bridge][,helper=helper][,ifname=ifname]\n"
" connects a host TAP network interface to a host bridge
device 'br'\n"
" (default=" DEFAULT_BRIDGE_INTERFACE ") using the program
'helper'\n"
" (default=" DEFAULT_BRIDGE_HELPER ")\n"
@@ -1621,7 +1621,7 @@ qemu-system-i386 linux.img \
-net nic -net
tap,"helper=/usr/local/libexec/qemu-bridge-helper"
@end example
-@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
+@item -netdev
bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}][,ifname=@var{ifname}]
@item -net
bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
Connect a host TAP network interface to a host bridge device.
@@ -1630,6 +1630,10 @@ attach it to the bridge. The default network helper
executable is
@file{/usr/local/libexec/qemu-bridge-helper} and the default bridge
device is @file{br0}.
+The name of the host tap interface can be changed by @var{ifname} parameter.
+The default value is @file{tapX} where X is a number. The parameter --ifname
+will be passed to the helper if this option is used.
+
Examples:
@example
@@ -1644,6 +1648,16 @@ qemu-system-i386 linux.img -net bridge -net
nic,model=virtio
qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
@end example
+@example
+# Create two virtual interfaces, put them into different bridges
+# and give interfaces meaningful names.
+# PS intbr and extbr should be allowed in /etc/qemu/bridge.conf
+qemu-system-x86_64 --enable-kvm -m 512 -name virt \
+-device e1000,mac=52:54:DB:22:F9:7D,netdev=extbr -netdev
bridge,id=extbr,br=extbr,ifname=virt_ext \
+-device e1000,mac=52:54:AC:8C:B6:6D,netdev=intbr -netdev
bridge,id=intbr,br=intbr,ifname=virt_int \
+-drive file=/home/virtuals/virt.raw,if=virtio
+@end example
+
@item -netdev
socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}]
[,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
--
1.8.2
--
Alexandre Kandalintsev
