interface: add udev based backend for virInterface

Add a read-only udev based backend for virInterface. Useful for distros
that do not have netcf support yet. Multiple libvirt based utilities use
a HAL based fallback when virInterface is not available which is less
than ideal. This implements:
* virConnectNumOfInterfaces()
* virConnectListInterfaces()
* virConnectNumOfDefinedInterfaces()
* virConnectListDefinedInterfaces()
* virConnectListAllInterfaces()
* virConnectInterfaceLookupByName()
* virConnectInterfaceLookupByMACString()
This commit is contained in:
Doug Goldstein 2012-10-06 14:20:25 -05:00 committed by Eric Blake
parent 9c74414ded
commit 5a33366f5c
5 changed files with 533 additions and 13 deletions

View File

@ -2809,18 +2809,12 @@ if test "$with_libvirtd" = "no" ; then
with_interface=no
fi
dnl The interface driver depends on the netcf library
if test "$with_interface:$with_netcf" = "check:yes" ; then
with_interface=yes
fi
if test "$with_interface:$with_netcf" = "check:no" ; then
with_interface=no
fi
if test "$with_interface:$with_netcf" = "yes:no" ; then
AC_MSG_ERROR([Requested the Interface driver without netcf support])
fi
dnl The interface driver depends on the netcf library or udev library
case $with_interface:$with_netcf:$with_udev in
check:*yes*) with_interface=yes ;;
check:no:no) with_interface=no ;;
yes:no:no) AC_MSG_ERROR([Requested the Interface driver without netcf or udev support]) ;;
esac
if test "$with_interface" = "yes" ; then
AC_DEFINE_UNQUOTED([WITH_INTERFACE], [1],

View File

@ -41,6 +41,7 @@ src/hyperv/hyperv_driver.c
src/hyperv/hyperv_util.c
src/hyperv/hyperv_wmi.c
src/interface/interface_backend_netcf.c
src/interface/interface_backend_udev.c
src/internal.h
src/libvirt.c
src/libvirt-qemu.c

View File

@ -558,11 +558,16 @@ INTERFACE_DRIVER_SOURCES =
if WITH_INTERFACE
INTERFACE_DRIVER_SOURCES += \
interface/interface_driver.h
endif
if WITH_NETCF
INTERFACE_DRIVER_SOURCES += \
interface/interface_backend_netcf.c
else
if HAVE_UDEV
INTERFACE_DRIVER_SOURCES += \
interface/interface_backend_udev.c
endif
endif
endif
SECRET_DRIVER_SOURCES = \
@ -1045,6 +1050,11 @@ libvirt_driver_interface_la_LIBADD =
if WITH_NETCF
libvirt_driver_interface_la_CFLAGS += $(NETCF_CFLAGS)
libvirt_driver_interface_la_LIBADD += $(NETCF_LIBS)
else
if HAVE_UDEV
libvirt_driver_interface_la_CFLAGS += $(UDEV_CFLAGS)
libvirt_driver_interface_la_LIBADD += $(UDEV_LIBS)
endif
endif
if WITH_DRIVER_MODULES
libvirt_driver_interface_la_LIBADD += ../gnulib/lib/libgnu.la

View File

@ -0,0 +1,513 @@
/*
* interface_backend_udev.c: udev backend for virInterface
*
* Copyright (C) 2012 Doug Goldstein <cardoe@cardoe.com>
*
* 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/>.
*/
#include <config.h>
#include <libudev.h>
#include "virterror_internal.h"
#include "datatypes.h"
#include "interface_driver.h"
#include "interface_conf.h"
#include "memory.h"
#define VIR_FROM_THIS VIR_FROM_INTERFACE
struct udev_iface_driver {
struct udev *udev;
};
typedef enum {
VIR_UDEV_IFACE_ACTIVE,
VIR_UDEV_IFACE_INACTIVE,
VIR_UDEV_IFACE_ALL
} virUdevStatus ;
static const char *
virUdevStatusString(virUdevStatus status)
{
switch (status) {
case VIR_UDEV_IFACE_ACTIVE:
return "active";
case VIR_UDEV_IFACE_INACTIVE:
return "inactive";
case VIR_UDEV_IFACE_ALL:
return "all";
}
return "";
}
static struct udev_enumerate * ATTRIBUTE_NONNULL(1)
udevIfaceGetDevices(struct udev *udev, virUdevStatus status)
{
struct udev_enumerate *enumerate;
/* Create a new enumeration to create a list */
enumerate = udev_enumerate_new(udev);
if (!enumerate)
return NULL;
/* Enumerate all network subsystem devices */
udev_enumerate_add_match_subsystem(enumerate, "net");
/* Ignore devices that are part of a bridge */
udev_enumerate_add_nomatch_sysattr(enumerate, "brport/state", NULL);
/* State of the device */
switch (status) {
case VIR_UDEV_IFACE_ACTIVE:
udev_enumerate_add_match_sysattr(enumerate, "operstate", "up");
break;
case VIR_UDEV_IFACE_INACTIVE:
udev_enumerate_add_match_sysattr(enumerate, "operstate", "down");
break;
case VIR_UDEV_IFACE_ALL:
break;
}
/* We don't want to see the TUN devices that QEMU creates for other guests
* running on this machine. By saying nomatch NULL, we just are getting
* devices without the tun_flags sysattr.
*/
udev_enumerate_add_nomatch_sysattr(enumerate, "tun_flags", NULL);
return enumerate;
}
static virDrvOpenStatus
udevIfaceOpenInterface(virConnectPtr conn,
virConnectAuthPtr auth ATTRIBUTE_UNUSED,
unsigned int flags)
{
struct udev_iface_driver *driverState = NULL;
virCheckFlags(0, VIR_DRV_OPEN_ERROR);
if (VIR_ALLOC(driverState) < 0) {
virReportOOMError();
goto err;
}
driverState->udev = udev_new();
if (!driverState->udev) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("failed to create udev context"));
goto err;
}
conn->interfacePrivateData = driverState;
return VIR_DRV_OPEN_SUCCESS;
err:
VIR_FREE(driverState);
return VIR_DRV_OPEN_ERROR;
}
static int
udevIfaceCloseInterface(virConnectPtr conn)
{
struct udev_iface_driver *driverState;
if (conn->interfacePrivateData != NULL) {
driverState = conn->interfacePrivateData;
udev_unref(driverState->udev);
VIR_FREE(driverState);
}
conn->interfacePrivateData = NULL;
return 0;
}
static int
udevIfaceNumOfInterfacesByStatus(virConnectPtr conn, virUdevStatus status)
{
struct udev_iface_driver *driverState = conn->interfacePrivateData;
struct udev *udev = udev_ref(driverState->udev);
struct udev_enumerate *enumerate = NULL;
struct udev_list_entry *devices;
struct udev_list_entry *dev_entry;
int count = 0;
enumerate = udevIfaceGetDevices(udev, status);
if (!enumerate) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("failed to get number of %s interfaces on host"),
virUdevStatusString(status));
count = -1;
goto err;
}
/* Do the scan to load up the enumeration */
udev_enumerate_scan_devices(enumerate);
/* Get a list we can walk */
devices = udev_enumerate_get_list_entry(enumerate);
/* For each item so we can count */
udev_list_entry_foreach(dev_entry, devices) {
count++;
}
err:
if (enumerate)
udev_enumerate_unref(enumerate);
udev_unref(udev);
return count;
}
static int
udevIfaceListInterfacesByStatus(virConnectPtr conn,
char **const names,
int names_len,
virUdevStatus status)
{
struct udev_iface_driver *driverState = conn->interfacePrivateData;
struct udev *udev = udev_ref(driverState->udev);
struct udev_enumerate *enumerate = NULL;
struct udev_list_entry *devices;
struct udev_list_entry *dev_entry;
int count = 0;
enumerate = udevIfaceGetDevices(udev, status);
if (!enumerate) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("failed to get list of %s interfaces on host"),
virUdevStatusString(status));
goto err;
}
/* Do the scan to load up the enumeration */
udev_enumerate_scan_devices(enumerate);
/* Get a list we can walk */
devices = udev_enumerate_get_list_entry(enumerate);
/* For each item so we can count */
udev_list_entry_foreach(dev_entry, devices) {
struct udev_device *dev;
const char *path;
/* Ensure we won't exceed the size of our array */
if (count > names_len)
break;
path = udev_list_entry_get_name(dev_entry);
dev = udev_device_new_from_syspath(udev, path);
names[count] = strdup(udev_device_get_sysname(dev));
udev_device_unref(dev);
/* If strdup() failed, we are out of memory */
if (!names[count]) {
virReportOOMError();
goto err;
}
count++;
}
udev_enumerate_unref(enumerate);
udev_unref(udev);
return count;
err:
if (enumerate)
udev_enumerate_unref(enumerate);
udev_unref(udev);
for (names_len = 0; names_len < count; names_len++)
VIR_FREE(names[names_len]);
return -1;
}
static int
udevIfaceNumOfInterfaces(virConnectPtr conn)
{
return udevIfaceNumOfInterfacesByStatus(conn, VIR_UDEV_IFACE_ACTIVE);
}
static int
udevIfaceListInterfaces(virConnectPtr conn,
char **const names,
int names_len)
{
return udevIfaceListInterfacesByStatus(conn, names, names_len,
VIR_UDEV_IFACE_ACTIVE);
}
static int
udevIfaceNumOfDefinedInterfaces(virConnectPtr conn)
{
return udevIfaceNumOfInterfacesByStatus(conn, VIR_UDEV_IFACE_INACTIVE);
}
static int
udevIfaceListDefinedInterfaces(virConnectPtr conn,
char **const names,
int names_len)
{
return udevIfaceListInterfacesByStatus(conn, names, names_len,
VIR_UDEV_IFACE_INACTIVE);
}
static int
udevIfaceListAllInterfaces(virConnectPtr conn,
virInterfacePtr **ifaces,
unsigned int flags)
{
struct udev_iface_driver *driverState = conn->interfacePrivateData;
struct udev *udev;
struct udev_enumerate *enumerate = NULL;
struct udev_list_entry *devices;
struct udev_list_entry *dev_entry;
virInterfacePtr *ifaces_list;
virInterfacePtr iface_obj;
int tmp_count;
int count = 0;
int status = 0;
int ret;
virCheckFlags(VIR_CONNECT_LIST_INTERFACES_ACTIVE |
VIR_CONNECT_LIST_INTERFACES_INACTIVE, -1);
/* Grab a udev reference */
udev = udev_ref(driverState->udev);
/* List all interfaces in case we support more filter flags in the future */
enumerate = udevIfaceGetDevices(udev, VIR_UDEV_IFACE_ALL);
if (!enumerate) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("failed to get list of %s interfaces on host"),
virUdevStatusString(status));
ret = -1;
goto cleanup;
}
/* Do the scan to load up the enumeration */
udev_enumerate_scan_devices(enumerate);
/* Get a list we can walk */
devices = udev_enumerate_get_list_entry(enumerate);
/* For each item so we can count */
udev_list_entry_foreach(dev_entry, devices) {
count++;
}
/* If we've got nothing, exit out */
if (count == 0) {
ret = 0;
goto cleanup;
}
/* If we're asked for the ifaces then alloc up memory */
if (ifaces) {
if (VIR_ALLOC_N(ifaces_list, count + 1) < 0) {
virReportOOMError();
ret = -1;
goto cleanup;
}
}
/* Get a list we can walk */
devices = udev_enumerate_get_list_entry(enumerate);
/* reset our iterator */
count = 0;
/* Walk through each device */
udev_list_entry_foreach(dev_entry, devices) {
struct udev_device *dev;
const char *path;
const char *name;
const char *macaddr;
int add_to_list;
path = udev_list_entry_get_name(dev_entry);
dev = udev_device_new_from_syspath(udev, path);
name = udev_device_get_sysname(dev);
macaddr = udev_device_get_sysattr_value(dev, "address");
status = STREQ(udev_device_get_sysattr_value(dev, "operstate"), "up");
udev_device_unref(dev);
/* Filter the results */
if (status && (flags & VIR_CONNECT_LIST_INTERFACES_ACTIVE))
add_to_list = 1;
else if (!status && (flags & VIR_CONNECT_LIST_INTERFACES_INACTIVE))
add_to_list = 1;
/* If we matched a filter, then add it */
if (add_to_list) {
if (ifaces) {
iface_obj = virGetInterface(conn, name, macaddr);
ifaces_list[count] = iface_obj;
}
count++;
}
}
/* Drop our refcounts */
udev_enumerate_unref(enumerate);
udev_unref(udev);
/* Trim the array to its final size */
if (ifaces) {
ignore_value(VIR_REALLOC_N(ifaces_list, count + 1));
*ifaces = ifaces_list;
}
return count;
cleanup:
if (enumerate)
udev_enumerate_unref(enumerate);
udev_unref(udev);
if (ifaces) {
for (tmp_count = 0; tmp_count < count; tmp_count++)
virInterfaceFree(ifaces_list[tmp_count]);
}
VIR_FREE(ifaces_list);
return ret;
}
static virInterfacePtr
udevIfaceLookupByName(virConnectPtr conn, const char *name)
{
struct udev_iface_driver *driverState = conn->interfacePrivateData;
struct udev *udev = udev_ref(driverState->udev);
struct udev_device *dev;
const char *macaddr;
virInterfacePtr ret = NULL;
/* get a device reference based on the device name */
dev = udev_device_new_from_subsystem_sysname(udev, "net", name);
if (!dev) {
virReportError(VIR_ERR_NO_INTERFACE,
_("couldn't find interface named '%s'"),
name);
goto err;
}
macaddr = udev_device_get_sysattr_value(dev, "address");
ret = virGetInterface(conn, name, macaddr);
udev_device_unref(dev);
err:
udev_unref(udev);
return ret;
}
static virInterfacePtr
udevIfaceLookupByMACString(virConnectPtr conn, const char *macstr)
{
struct udev_iface_driver *driverState = conn->interfacePrivateData;
struct udev *udev = udev_ref(driverState->udev);
struct udev_enumerate *enumerate = NULL;
struct udev_list_entry *dev_entry;
struct udev_device *dev;
const char *name;
virInterfacePtr ret = NULL;
enumerate = udevIfaceGetDevices(udev, VIR_UDEV_IFACE_ALL);
if (!enumerate) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("failed to lookup interface with MAC address '%s'"),
macstr);
goto err;
}
/* Match on MAC */
udev_enumerate_add_match_sysattr(enumerate, "address", macstr);
/* Do the scan to load up the enumeration */
udev_enumerate_scan_devices(enumerate);
/* Get a list we can walk */
dev_entry = udev_enumerate_get_list_entry(enumerate);
/* Check that we got something back */
if (!dev_entry) {
virReportError(VIR_ERR_NO_INTERFACE,
_("couldn't find interface with MAC address '%s'"),
macstr);
goto err;
}
/* Check that we didn't get multiple items back */
if (udev_list_entry_get_next(dev_entry)) {
virReportError(VIR_ERR_MULTIPLE_INTERFACES,
_("the MAC address '%s' matches multiple interfaces"),
macstr);
goto err;
}
dev = udev_device_new_from_syspath(udev, udev_list_entry_get_name(dev_entry));
name = udev_device_get_sysname(dev);
ret = virGetInterface(conn, name, macstr);
udev_device_unref(dev);
err:
if (enumerate)
udev_enumerate_unref(enumerate);
udev_unref(udev);
return ret;
}
static virInterfaceDriver udevIfaceDriver = {
"udev",
.open = udevIfaceOpenInterface, /* 0.10.3 */
.close = udevIfaceCloseInterface, /* 0.10.3 */
.numOfInterfaces = udevIfaceNumOfInterfaces, /* 0.10.3 */
.listInterfaces = udevIfaceListInterfaces, /* 0.10.3 */
.numOfDefinedInterfaces = udevIfaceNumOfDefinedInterfaces, /* 0.10.3 */
.listDefinedInterfaces = udevIfaceListDefinedInterfaces, /* 0.10.3 */
.listAllInterfaces = udevIfaceListAllInterfaces, /* 0.10.3 */
.interfaceLookupByName = udevIfaceLookupByName, /* 0.10.3 */
.interfaceLookupByMACString = udevIfaceLookupByMACString, /* 0.10.3 */
};
int
interfaceRegister(void) {
if (virRegisterInterfaceDriver(&udevIfaceDriver) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("failed to register udev interface driver"));
return -1;
}
return 0;
}

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@ -2708,6 +2708,8 @@ vshShowVersion(vshControl *ctl ATTRIBUTE_UNUSED)
vshPrint(ctl, " Interface");
# if defined(WITH_NETCF)
vshPrint(ctl, " netcf");
# elif defined(HAVE_UDEV)
vshPrint(ctl, " udev");
# endif
#endif
#ifdef WITH_NWFILTER