libvirt/src/util/virnetlink.h
Laine Stump 97d26e470d util: fallback to ioctl(SIOCBRDELBR) if netlink RTM_DELLINK fails
commit 09778e09 switched from using ioctl(SIOCBRDELBR) for bridge
device deletion to using a netlink RTM_DELLINK message, which is the
more modern way to delete a bridge (and also doesn't require the
bridge to be ~IFF_UP to succeed). However, although older kernels
(e.g. 2.6.32, in RHEL6/CentOS6) support deleting *some* link types
with RTM_NEWLINK, they don't support deleting bridges, and there is no
compile-time way to figure this out.

This patch moves the body of the SIOCBRDELBR version of
virNetDevBridgeDelete() into a static function, calls the new function
from the original, and also calls the new function from the
RTM_DELLINK version if the RTM_DELLINK message generates an EOPNOTSUPP
error. Since RTM_DELLINK is done from the subordinate function
virNetlinkDelLink, which is also called for other purposes (deleting a
macvtap interface), a function pointer called "fallback" has been
added to the arglist of virNetlinkDelLink() - if that arg != NULL, the
provided function will be called when (and only when) RTM_DELLINK
fails with EOPNOTSUPP.

Resolves:  https://bugzilla.redhat.com/show_bug.cgi?id=1252780 (part 2)
2015-08-28 16:39:30 -04:00

111 lines
3.6 KiB
C

/*
* Copyright (C) 2010-2013, 2015 Red Hat, Inc.
* Copyright (C) 2010-2012 IBM Corporation
*
* 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/>.
*/
#ifndef __VIR_NETLINK_H__
# define __VIR_NETLINK_H__
# include "internal.h"
# include "virmacaddr.h"
# if defined(__linux__) && defined(HAVE_LIBNL)
/* Work around a bug where older libnl-1 headers expected older gcc
* semantics of 'extern inline' that conflict with C99 semantics. */
# ifdef HAVE_LIBNL1
# define inline
# endif
# include <netlink/msg.h>
# ifdef HAVE_LIBNL1
# undef inline
# endif
# else
struct nl_msg;
struct sockaddr_nl;
struct nlattr;
struct nlmsghdr;
# endif /* __linux__ */
int virNetlinkStartup(void);
void virNetlinkShutdown(void);
int virNetlinkCommand(struct nl_msg *nl_msg,
struct nlmsghdr **resp, unsigned int *respbuflen,
uint32_t src_pid, uint32_t dst_pid,
unsigned int protocol, unsigned int groups);
typedef int (*virNetlinkDelLinkFallback)(const char *ifname);
int virNetlinkDelLink(const char *ifname, virNetlinkDelLinkFallback fallback);
int virNetlinkGetErrorCode(struct nlmsghdr *resp, unsigned int recvbuflen);
typedef void (*virNetlinkEventHandleCallback)(struct nlmsghdr *,
unsigned int length,
struct sockaddr_nl *peer,
bool *handled,
void *opaque);
typedef void (*virNetlinkEventRemoveCallback)(int watch,
const virMacAddr *macaddr,
void *opaque);
/**
* stopNetlinkEventServer: stop the monitor to receive netlink messages for libvirtd
*/
int virNetlinkEventServiceStop(unsigned int protocol);
/**
* stopNetlinkEventServerAll: stop all the monitors to receive netlink messages for libvirtd
*/
int virNetlinkEventServiceStopAll(void);
/**
* startNetlinkEventServer: start a monitor to receive netlink messages for libvirtd
*/
int virNetlinkEventServiceStart(unsigned int protocol, unsigned int groups);
/**
* virNetlinkEventServiceIsRunning: returns if the netlink event service is running.
*/
bool virNetlinkEventServiceIsRunning(unsigned int protocol);
/**
* virNetlinkEventServiceLocalPid: returns nl_pid used to bind() netlink socket
*/
int virNetlinkEventServiceLocalPid(unsigned int protocol);
/**
* virNetlinkEventAddClient: register a callback for handling of netlink messages
*/
int virNetlinkEventAddClient(virNetlinkEventHandleCallback handleCB,
virNetlinkEventRemoveCallback removeCB,
void *opaque, const virMacAddr *macaddr,
unsigned int protocol);
/**
* virNetlinkEventRemoveClient: unregister a callback from a netlink monitor
*/
int virNetlinkEventRemoveClient(int watch, const virMacAddr *macaddr,
unsigned int protocol);
#endif /* __VIR_NETLINK_H__ */