libvirt/src/qemu/qemu_interface.c

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/*
* qemu_interface.c: QEMU interface management
*
* Copyright (C) 2015-2016 Red Hat, Inc.
* Copyright IBM Corp. 2014
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*
* Authors:
* Matthew J. Rosato <mjrosato@linux.vnet.ibm.com>
*/
#include <config.h>
#include "network_conf.h"
#include "domain_audit.h"
#include "domain_nwfilter.h"
#include "qemu_interface.h"
#include "passfd.h"
#include "viralloc.h"
#include "virlog.h"
#include "virstring.h"
#include "virnetdev.h"
#include "virnetdevtap.h"
#include "virnetdevmacvlan.h"
#include "virnetdevbridge.h"
#include "virnetdevvportprofile.h"
#include <sys/stat.h>
#include <fcntl.h>
#define VIR_FROM_THIS VIR_FROM_QEMU
VIR_LOG_INIT("qemu.qemu_interface");
/**
* qemuInterfaceStartDevice:
* @net: net device to start
*
* Based upon the type of device provided, perform the appropriate
* work to completely activate the device and make it reachable from
* the rest of the network.
*/
int
qemuInterfaceStartDevice(virDomainNetDefPtr net)
{
int ret = -1;
virDomainNetType actualType = virDomainNetGetActualType(net);
switch (actualType) {
case VIR_DOMAIN_NET_TYPE_BRIDGE:
case VIR_DOMAIN_NET_TYPE_NETWORK:
if (virDomainNetGetActualBridgeMACTableManager(net)
== VIR_NETWORK_BRIDGE_MAC_TABLE_MANAGER_LIBVIRT) {
/* libvirt is managing the FDB of the bridge this device
* is attaching to, so we have turned off learning and
* unicast_flood on the device to prevent the kernel from
* adding any FDB entries for it. This means we need to
* add an fdb entry ourselves, using the MAC address from
* the interface config.
*/
if (virNetDevBridgeFDBAdd(&net->mac, net->ifname,
VIR_NETDEVBRIDGE_FDB_FLAG_MASTER |
VIR_NETDEVBRIDGE_FDB_FLAG_TEMP) < 0)
goto cleanup;
}
break;
case VIR_DOMAIN_NET_TYPE_DIRECT: {
const char *physdev = virDomainNetGetActualDirectDev(net);
bool isOnline = true;
/* set the physdev online if necessary. It may already be up,
* in which case we shouldn't re-up it just in case that causes
* some sort of "blip" in the physdev's status.
*/
if (physdev && virNetDevGetOnline(physdev, &isOnline) < 0)
goto cleanup;
if (!isOnline && virNetDevSetOnline(physdev, true) < 0)
goto cleanup;
/* macvtap devices share their MAC address with the guest
* domain, and if they are set online prior to the domain CPUs
* being started, the host may send out traffic from this
* device that could confuse other entities on the network (in
* particular, if this new domain is the destination of a
* migration, and the source domain is still running, another
* host may mistakenly direct traffic for the guest to the
* destination domain rather than source domain). To prevent
* this, we create the macvtap device with IFF_UP false
* (i.e. "offline") then wait to bring it online until just as
* we are starting the domain CPUs.
*/
if (virNetDevSetOnline(net->ifname, true) < 0)
goto cleanup;
break;
}
case VIR_DOMAIN_NET_TYPE_ETHERNET:
if (virNetDevIPInfoAddToDev(net->ifname, &net->hostIP) < 0)
goto cleanup;
break;
case VIR_DOMAIN_NET_TYPE_USER:
case VIR_DOMAIN_NET_TYPE_VHOSTUSER:
case VIR_DOMAIN_NET_TYPE_SERVER:
case VIR_DOMAIN_NET_TYPE_CLIENT:
case VIR_DOMAIN_NET_TYPE_MCAST:
case VIR_DOMAIN_NET_TYPE_UDP:
case VIR_DOMAIN_NET_TYPE_INTERNAL:
case VIR_DOMAIN_NET_TYPE_HOSTDEV:
case VIR_DOMAIN_NET_TYPE_LAST:
/* these types all require no action */
break;
}
ret = 0;
cleanup:
return ret;
}
/**
* qemuInterfaceStartDevices:
* @def: domain definition
*
* Set all ifaces associated with this domain to the online state.
*/
int
qemuInterfaceStartDevices(virDomainDefPtr def)
{
size_t i;
for (i = 0; i < def->nnets; i++) {
if (qemuInterfaceStartDevice(def->nets[i]) < 0)
return -1;
}
return 0;
}
/**
* qemuInterfaceStopDevice:
* @net: net device to stop
*
* Based upon the type of device provided, perform the appropriate
* work to deactivate the device so that packets aren't forwarded to
* it from the rest of the network.
*/
int
qemuInterfaceStopDevice(virDomainNetDefPtr net)
{
int ret = -1;
virDomainNetType actualType = virDomainNetGetActualType(net);
switch (actualType) {
case VIR_DOMAIN_NET_TYPE_BRIDGE:
case VIR_DOMAIN_NET_TYPE_NETWORK:
if (virDomainNetGetActualBridgeMACTableManager(net)
== VIR_NETWORK_BRIDGE_MAC_TABLE_MANAGER_LIBVIRT) {
/* remove the FDB entries that were added during
* qemuInterfaceStartDevices()
*/
if (virNetDevBridgeFDBDel(&net->mac, net->ifname,
VIR_NETDEVBRIDGE_FDB_FLAG_MASTER |
VIR_NETDEVBRIDGE_FDB_FLAG_TEMP) < 0)
goto cleanup;
}
break;
case VIR_DOMAIN_NET_TYPE_DIRECT: {
const char *physdev = virDomainNetGetActualDirectDev(net);
/* macvtap interfaces need to be marked !IFF_UP (ie "down") to
* prevent any host-generated traffic sent from this interface
* from putting bad info into the arp caches of other machines
* on this network.
*/
if (virNetDevSetOnline(net->ifname, false) < 0)
goto cleanup;
/* also mark the physdev down for passthrough macvtap, as the
* physdev has the same MAC address as the macvtap device.
*/
if (virDomainNetGetActualDirectMode(net) ==
VIR_NETDEV_MACVLAN_MODE_PASSTHRU &&
physdev && virNetDevSetOnline(physdev, false) < 0)
goto cleanup;
break;
}
case VIR_DOMAIN_NET_TYPE_ETHERNET:
case VIR_DOMAIN_NET_TYPE_USER:
case VIR_DOMAIN_NET_TYPE_VHOSTUSER:
case VIR_DOMAIN_NET_TYPE_SERVER:
case VIR_DOMAIN_NET_TYPE_CLIENT:
case VIR_DOMAIN_NET_TYPE_MCAST:
case VIR_DOMAIN_NET_TYPE_UDP:
case VIR_DOMAIN_NET_TYPE_INTERNAL:
case VIR_DOMAIN_NET_TYPE_HOSTDEV:
case VIR_DOMAIN_NET_TYPE_LAST:
/* these types all require no action */
break;
}
ret = 0;
cleanup:
return ret;
}
/**
* qemuInterfaceStopDevices:
* @def: domain definition
*
* Make all interfaces associated with this domain inaccessible from
* the rest of the network.
*/
int
qemuInterfaceStopDevices(virDomainDefPtr def)
{
size_t i;
for (i = 0; i < def->nnets; i++) {
if (qemuInterfaceStopDevice(def->nets[i]) < 0)
return -1;
}
return 0;
}
/**
* qemuInterfaceDirectConnect:
* @def: the definition of the VM (needed by 802.1Qbh and audit)
* @driver: pointer to the driver instance
* @net: pointer to the VM's interface description with direct device type
* @tapfd: array of file descriptor return value for the new device
* @tapfdSize: number of file descriptors in @tapfd
* @vmop: VM operation type
*
* Returns 0 on success or -1 in case of error.
*/
int
qemuInterfaceDirectConnect(virDomainDefPtr def,
virQEMUDriverPtr driver,
virDomainNetDefPtr net,
int *tapfd,
size_t tapfdSize,
virNetDevVPortProfileOp vmop)
{
int ret = -1;
char *res_ifname = NULL;
virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
unsigned int macvlan_create_flags = VIR_NETDEV_MACVLAN_CREATE_WITH_TAP;
if (net->model && STREQ(net->model, "virtio"))
macvlan_create_flags |= VIR_NETDEV_MACVLAN_VNET_HDR;
if (virNetDevMacVLanCreateWithVPortProfile(net->ifname,
&net->mac,
virDomainNetGetActualDirectDev(net),
virDomainNetGetActualDirectMode(net),
virDomainNetGetActualVlan(net),
def->uuid,
virDomainNetGetActualVirtPortProfile(net),
&res_ifname,
vmop, cfg->stateDir,
tapfd, tapfdSize,
macvlan_create_flags) < 0)
goto cleanup;
virDomainAuditNetDevice(def, net, res_ifname, true);
VIR_FREE(net->ifname);
net->ifname = res_ifname;
ret = 0;
cleanup:
if (ret < 0) {
while (tapfdSize--)
VIR_FORCE_CLOSE(tapfd[tapfdSize]);
}
virObjectUnref(cfg);
return ret;
}
/**
* qemuCreateInBridgePortWithHelper:
* @cfg: the configuration object in which the helper name is looked up
* @brname: the bridge name
* @ifname: the returned interface name
* @macaddr: the returned MAC address
* @tapfd: file descriptor return value for the new tap device
* @flags: OR of virNetDevTapCreateFlags:
* VIR_NETDEV_TAP_CREATE_VNET_HDR
* - Enable IFF_VNET_HDR on the tap device
*
* This function creates a new tap device on a bridge using an external
* helper. The final name for the bridge will be stored in @ifname.
*
* Returns 0 in case of success or -1 on failure
*/
static int
qemuCreateInBridgePortWithHelper(virQEMUDriverConfigPtr cfg,
const char *brname,
char **ifname,
int *tapfd,
unsigned int flags)
{
virCommandPtr cmd;
char *errbuf = NULL, *cmdstr = NULL;
int pair[2] = { -1, -1 };
if ((flags & ~VIR_NETDEV_TAP_CREATE_VNET_HDR) != VIR_NETDEV_TAP_CREATE_IFUP)
return -1;
if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) < 0) {
virReportSystemError(errno, "%s", _("failed to create socket"));
return -1;
}
if (!virFileIsExecutable(cfg->bridgeHelperName)) {
virReportSystemError(errno, _("'%s' is not a suitable bridge helper"),
cfg->bridgeHelperName);
return -1;
}
cmd = virCommandNew(cfg->bridgeHelperName);
if (flags & VIR_NETDEV_TAP_CREATE_VNET_HDR)
virCommandAddArgFormat(cmd, "--use-vnet");
virCommandAddArgFormat(cmd, "--br=%s", brname);
virCommandAddArgFormat(cmd, "--fd=%d", pair[1]);
virCommandSetErrorBuffer(cmd, &errbuf);
virCommandDoAsyncIO(cmd);
virCommandPassFD(cmd, pair[1],
VIR_COMMAND_PASS_FD_CLOSE_PARENT);
virCommandClearCaps(cmd);
#ifdef CAP_NET_ADMIN
virCommandAllowCap(cmd, CAP_NET_ADMIN);
#endif
if (virCommandRunAsync(cmd, NULL) < 0) {
*tapfd = -1;
goto cleanup;
}
do {
*tapfd = recvfd(pair[0], 0);
} while (*tapfd < 0 && errno == EINTR);
if (*tapfd < 0) {
char ebuf[1024];
char *errstr = NULL;
if (!(cmdstr = virCommandToString(cmd)))
goto cleanup;
virCommandAbort(cmd);
if (errbuf && *errbuf &&
virAsprintf(&errstr, "\nstderr=%s", errbuf) < 0)
goto cleanup;
virReportError(VIR_ERR_INTERNAL_ERROR,
_("%s: failed to communicate with bridge helper: %s%s"),
cmdstr, virStrerror(errno, ebuf, sizeof(ebuf)),
errstr ? errstr : "");
VIR_FREE(errstr);
goto cleanup;
}
if (virNetDevTapGetName(*tapfd, ifname) < 0 ||
virCommandWait(cmd, NULL) < 0) {
VIR_FORCE_CLOSE(*tapfd);
*tapfd = -1;
}
cleanup:
VIR_FREE(cmdstr);
VIR_FREE(errbuf);
virCommandFree(cmd);
VIR_FORCE_CLOSE(pair[0]);
return *tapfd < 0 ? -1 : 0;
}
/* qemuInterfaceEthernetConnect:
* @def: the definition of the VM
* @driver: qemu driver data
* @net: pointer to the VM's interface description
* @tapfd: array of file descriptor return value for the new device
* @tapfdsize: number of file descriptors in @tapfd
*
* Called *only* called if actualType is VIR_DOMAIN_NET_TYPE_ETHERNET
* (i.e. if the connection is made with a tap device)
*/
int
qemuInterfaceEthernetConnect(virDomainDefPtr def,
virQEMUDriverPtr driver,
virDomainNetDefPtr net,
int *tapfd,
size_t tapfdSize)
{
virMacAddr tapmac;
int ret = -1;
unsigned int tap_create_flags = VIR_NETDEV_TAP_CREATE_IFUP;
bool template_ifname = false;
virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
const char *tunpath = "/dev/net/tun";
if (net->backend.tap) {
tunpath = net->backend.tap;
if (!virQEMUDriverIsPrivileged(driver)) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("cannot use custom tap device in session mode"));
goto cleanup;
}
}
if (!net->ifname ||
STRPREFIX(net->ifname, VIR_NET_GENERATED_PREFIX) ||
strchr(net->ifname, '%')) {
VIR_FREE(net->ifname);
if (VIR_STRDUP(net->ifname, VIR_NET_GENERATED_PREFIX "%d") < 0)
goto cleanup;
/* avoid exposing vnet%d in getXMLDesc or error outputs */
template_ifname = true;
}
if (net->model && STREQ(net->model, "virtio"))
tap_create_flags |= VIR_NETDEV_TAP_CREATE_VNET_HDR;
if (virNetDevTapCreate(&net->ifname, tunpath, tapfd, tapfdSize,
tap_create_flags) < 0) {
virDomainAuditNetDevice(def, net, tunpath, false);
goto cleanup;
}
virDomainAuditNetDevice(def, net, tunpath, true);
virMacAddrSet(&tapmac, &net->mac);
tapmac.addr[0] = 0xFE;
if (virNetDevSetMAC(net->ifname, &tapmac) < 0)
goto cleanup;
if (virNetDevSetOnline(net->ifname, true) < 0)
goto cleanup;
if (net->script &&
virNetDevRunEthernetScript(net->ifname, net->script) < 0)
goto cleanup;
if (cfg->macFilter &&
ebtablesAddForwardAllowIn(driver->ebtables,
net->ifname,
&net->mac) < 0)
goto cleanup;
if (net->filter &&
virDomainConfNWFilterInstantiate(def->uuid, net) < 0) {
goto cleanup;
}
ret = 0;
cleanup:
if (ret < 0) {
size_t i;
for (i = 0; i < tapfdSize && tapfd[i] >= 0; i++)
VIR_FORCE_CLOSE(tapfd[i]);
if (template_ifname)
VIR_FREE(net->ifname);
}
virObjectUnref(cfg);
return ret;
}
/* qemuInterfaceBridgeConnect:
* @def: the definition of the VM
* @driver: qemu driver data
* @net: pointer to the VM's interface description
* @tapfd: array of file descriptor return value for the new device
* @tapfdsize: number of file descriptors in @tapfd
*
* Called *only* called if actualType is VIR_DOMAIN_NET_TYPE_NETWORK or
* VIR_DOMAIN_NET_TYPE_BRIDGE (i.e. if the connection is made with a tap
* device connecting to a bridge device)
*/
int
qemuInterfaceBridgeConnect(virDomainDefPtr def,
virQEMUDriverPtr driver,
virDomainNetDefPtr net,
int *tapfd,
qemu: propagate bridge MTU into qemu "host_mtu" option libvirt was able to set the host_mtu option when an MTU was explicitly given in the interface config (with <mtu size='n'/>), set the MTU of a libvirt network in the network config (with the same named subelement), and would automatically set the MTU of any tap device to the MTU of the network. This patch ties that all together (for networks based on tap devices and either Linux host bridges or OVS bridges) by learning the MTU of the network (i.e. the bridge) during qemuInterfaceBridgeConnect(), and returning that value so that it can then be passed to qemuBuildNicDevStr(); qemuBuildNicDevStr() then sets host_mtu in the interface's commandline options. The result is that a higher MTU for all guests connecting to a particular network will be plumbed top to bottom by simply changing the MTU of the network (in libvirt's config for libvirt-managed networks, or directly on the bridge device for simple host bridges or OVS bridges managed outside of libvirt). One question I have about this - it occurred to me that in the case of migrating a guest from a host with an older libvirt to one with a newer libvirt, the guest may have *not* had the host_mtu option on the older machine, but *will* have it on the newer machine. I'm curious if this could lead to incompatibilities between source and destination (I guess it all depends on whether or not the setting of host_mtu has a practical effect on a guest that is already running - Maxime?) Likewise, we could run into problems when migrating from a newer libvirt to older libvirt - The guest would have been told of the higher MTU on the newer libvirt, then migrated to a host that didn't understand <mtu size='blah'/>. (If this really is a problem, it would be a problem with or without the current patch).
2017-02-03 16:55:20 +00:00
size_t *tapfdSize,
unsigned int *mtu)
{
const char *brname;
int ret = -1;
unsigned int tap_create_flags = VIR_NETDEV_TAP_CREATE_IFUP;
bool template_ifname = false;
virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
const char *tunpath = "/dev/net/tun";
if (net->backend.tap) {
tunpath = net->backend.tap;
if (!(virQEMUDriverIsPrivileged(driver))) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("cannot use custom tap device in session mode"));
goto cleanup;
}
}
if (!(brname = virDomainNetGetActualBridgeName(net))) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("Missing bridge name"));
goto cleanup;
}
if (!net->ifname ||
STRPREFIX(net->ifname, VIR_NET_GENERATED_PREFIX) ||
strchr(net->ifname, '%')) {
VIR_FREE(net->ifname);
if (VIR_STRDUP(net->ifname, VIR_NET_GENERATED_PREFIX "%d") < 0)
goto cleanup;
/* avoid exposing vnet%d in getXMLDesc or error outputs */
template_ifname = true;
}
if (net->model && STREQ(net->model, "virtio"))
tap_create_flags |= VIR_NETDEV_TAP_CREATE_VNET_HDR;
if (virQEMUDriverIsPrivileged(driver)) {
if (virNetDevTapCreateInBridgePort(brname, &net->ifname, &net->mac,
def->uuid, tunpath, tapfd, *tapfdSize,
virDomainNetGetActualVirtPortProfile(net),
virDomainNetGetActualVlan(net),
qemu: propagate bridge MTU into qemu "host_mtu" option libvirt was able to set the host_mtu option when an MTU was explicitly given in the interface config (with <mtu size='n'/>), set the MTU of a libvirt network in the network config (with the same named subelement), and would automatically set the MTU of any tap device to the MTU of the network. This patch ties that all together (for networks based on tap devices and either Linux host bridges or OVS bridges) by learning the MTU of the network (i.e. the bridge) during qemuInterfaceBridgeConnect(), and returning that value so that it can then be passed to qemuBuildNicDevStr(); qemuBuildNicDevStr() then sets host_mtu in the interface's commandline options. The result is that a higher MTU for all guests connecting to a particular network will be plumbed top to bottom by simply changing the MTU of the network (in libvirt's config for libvirt-managed networks, or directly on the bridge device for simple host bridges or OVS bridges managed outside of libvirt). One question I have about this - it occurred to me that in the case of migrating a guest from a host with an older libvirt to one with a newer libvirt, the guest may have *not* had the host_mtu option on the older machine, but *will* have it on the newer machine. I'm curious if this could lead to incompatibilities between source and destination (I guess it all depends on whether or not the setting of host_mtu has a practical effect on a guest that is already running - Maxime?) Likewise, we could run into problems when migrating from a newer libvirt to older libvirt - The guest would have been told of the higher MTU on the newer libvirt, then migrated to a host that didn't understand <mtu size='blah'/>. (If this really is a problem, it would be a problem with or without the current patch).
2017-02-03 16:55:20 +00:00
net->mtu, mtu,
tap_create_flags) < 0) {
virDomainAuditNetDevice(def, net, tunpath, false);
goto cleanup;
}
if (virDomainNetGetActualBridgeMACTableManager(net)
== VIR_NETWORK_BRIDGE_MAC_TABLE_MANAGER_LIBVIRT) {
/* libvirt is managing the FDB of the bridge this device
* is attaching to, so we need to turn off learning and
* unicast_flood on the device to prevent the kernel from
* adding any FDB entries for it. We will add add an fdb
* entry ourselves (during qemuInterfaceStartDevices(),
* using the MAC address from the interface config.
*/
if (virNetDevBridgePortSetLearning(brname, net->ifname, false) < 0)
goto cleanup;
if (virNetDevBridgePortSetUnicastFlood(brname, net->ifname, false) < 0)
goto cleanup;
}
} else {
if (qemuCreateInBridgePortWithHelper(cfg, brname,
&net->ifname,
tapfd, tap_create_flags) < 0) {
virDomainAuditNetDevice(def, net, tunpath, false);
goto cleanup;
}
/* qemuCreateInBridgePortWithHelper can only create a single FD */
if (*tapfdSize > 1) {
VIR_WARN("Ignoring multiqueue network request");
*tapfdSize = 1;
}
}
virDomainAuditNetDevice(def, net, tunpath, true);
if (cfg->macFilter &&
ebtablesAddForwardAllowIn(driver->ebtables,
net->ifname,
&net->mac) < 0)
goto cleanup;
if (net->filter &&
virDomainConfNWFilterInstantiate(def->uuid, net) < 0) {
goto cleanup;
}
ret = 0;
cleanup:
if (ret < 0) {
size_t i;
for (i = 0; i < *tapfdSize && tapfd[i] >= 0; i++)
VIR_FORCE_CLOSE(tapfd[i]);
if (template_ifname)
VIR_FREE(net->ifname);
}
virObjectUnref(cfg);
return ret;
}
/**
* qemuInterfaceOpenVhostNet:
* @def: domain definition
* @net: network definition
* @qemuCaps: qemu binary capabilities
* @vhostfd: array of opened vhost-net device
* @vhostfdSize: number of file descriptors in @vhostfd array
*
* Open vhost-net, multiple times - if requested.
* In case, no vhost-net is needed, @vhostfdSize is set to 0
* and 0 is returned.
*
* Returns: 0 on success
* -1 on failure
*/
int
qemuInterfaceOpenVhostNet(virDomainDefPtr def,
virDomainNetDefPtr net,
virQEMUCapsPtr qemuCaps,
int *vhostfd,
size_t *vhostfdSize)
{
size_t i;
const char *vhostnet_path = net->backend.vhost;
if (!vhostnet_path)
vhostnet_path = "/dev/vhost-net";
/* If running a plain QEMU guest, or
* if the config says explicitly to not use vhost, return now*/
if (def->virtType != VIR_DOMAIN_VIRT_KVM ||
net->driver.virtio.name == VIR_DOMAIN_NET_BACKEND_TYPE_QEMU) {
*vhostfdSize = 0;
return 0;
}
/* If qemu doesn't support vhost-net mode (including the -netdev command
* option), don't try to open the device.
*/
if (!(virQEMUCapsGet(qemuCaps, QEMU_CAPS_VHOST_NET) &&
qemuDomainSupportsNetdev(def, qemuCaps, net))) {
if (net->driver.virtio.name == VIR_DOMAIN_NET_BACKEND_TYPE_VHOST) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
"%s", _("vhost-net is not supported with "
"this QEMU binary"));
return -1;
}
*vhostfdSize = 0;
return 0;
}
/* If the nic model isn't virtio, don't try to open. */
if (!(net->model && STREQ(net->model, "virtio"))) {
if (net->driver.virtio.name == VIR_DOMAIN_NET_BACKEND_TYPE_VHOST) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
"%s", _("vhost-net is only supported for "
"virtio network interfaces"));
return -1;
}
*vhostfdSize = 0;
return 0;
}
for (i = 0; i < *vhostfdSize; i++) {
vhostfd[i] = open(vhostnet_path, O_RDWR);
/* If the config says explicitly to use vhost and we couldn't open it,
* report an error.
*/
if (vhostfd[i] < 0) {
virDomainAuditNetDevice(def, net, vhostnet_path, false);
if (net->driver.virtio.name == VIR_DOMAIN_NET_BACKEND_TYPE_VHOST) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
"%s", _("vhost-net was requested for an interface, "
"but is unavailable"));
goto error;
}
VIR_WARN("Unable to open vhost-net. Opened so far %zu, requested %zu",
i, *vhostfdSize);
*vhostfdSize = i;
break;
}
}
virDomainAuditNetDevice(def, net, vhostnet_path, *vhostfdSize);
return 0;
error:
while (i--)
VIR_FORCE_CLOSE(vhostfd[i]);
return -1;
}