Currently there is a hook function that is invoked when a
new client connection comes in, which allows an app to
setup private data. This setup will make it difficult to
serialize client state during process re-exec(). Change to
a model where the app registers a callback when creating
the virNetServerPtr instance, which is used to allocate
the client private data immediately during virNetClientPtr
construction.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Daemon uses the following pattern when dispatching APIs with typed
parameters:
VIR_ALLOC_N(params, nparams);
virDomain*(dom, params, &nparams, flags);
virTypedParameterArrayClear(params, nparams);
In case nparams was originally set to 0, virDomain* API would fill it
with the number of typed parameters it can provide and we would use this
number (rather than zero) to clear params. Because VIR_ALLOC* returns
non-NULL pointer even if size is 0, the code would end up walking
through random memory. If we were lucky enough and the memory contained
7 (VIR_TYPED_PARAM_STRING) at the right place, we would try to free a
random pointer and crash.
Let's make sure params stays NULL when nparams is 0.
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
Update the libvirtd dispatch code to use virReportError
instead of the virNetError custom macro
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
When the guest changes its memory balloon applications may want
to know what the new value is, without having to periodically
poll on XML / domain info. Introduce a "balloon change" event
to let apps see this
* include/libvirt/libvirt.h.in: Define the
virConnectDomainEventBalloonChangeCallback callback
and VIR_DOMAIN_EVENT_ID_BALLOON_CHANGE constant
* python/libvirt-override-virConnect.py,
python/libvirt-override.c: Wire up helpers for new event
* daemon/remote.c: Helper for serializing balloon event
* examples/domain-events/events-c/event-test.c,
examples/domain-events/events-python/event-test.py: Add
example of balloon event usage
* src/conf/domain_event.c, src/conf/domain_event.h: Handling
of balloon events
* src/remote/remote_driver.c: Add handler of balloon events
* src/remote/remote_protocol.x: Define wire protocol for
balloon events
* src/remote_protocol-structs: Likewise.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The callback that is invoked when a new RPC client is
initialized does not have any opaque parameter. Add
one so that custom data can be passed into the callback
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The generator doesn't handle lists of virDomainSnapshotPtr, so
this commit requires a bit more work than some RPC additions.
* src/remote/remote_protocol.x
(REMOTE_PROC_DOMAIN_LIST_ALL_SNAPSHOTS)
(REMOTE_PROC_DOMAIN_SNAPSHOT_LIST_ALL_CHILDREN): New RPC calls,
with corresponding structs.
* daemon/remote.c (remoteDispatchDomainListAllSnapshots)
(remoteDispatchDomainSnapshotListAllChildren): New functions.
* src/remote/remote_driver.c (remoteDomainListAllSnapshots)
(remoteDomainSnapshotListAllChildren): Likewise.
* src/remote_protocol-structs: Regenerate.
This patch wires up the RPC protocol handlers for
virConnectListAllDomains(). The RPC generator has no support for the way
how virConnectListAllDomains() returns the results so the handler code
had to be done manually.
The new api is handled by REMOTE_PROC_CONNECT_LIST_ALL_DOMAINS, with
number 273 and marked with high priority.
Commit 2223ea98 removed the only use of 'server' param in
remoteDispatchAuthPolkit(). Mark the parameter with ATTRIBUTE_UNUSED
to fix the build when configuring with polkit0.
DBus connection. The HAL device code further requires that
the DBus connection is integrated with the event loop and
provides such glue logic itself.
The forthcoming FirewallD integration also requires a
dbus connection with event loop integration. Thus we need
to pull the current event loop glue out of the HAL driver.
Thus we create src/util/virdbus.{c,h} files. This contains
just one method virDBusGetSystemBus() which obtains a handle
to the single shared system bus instance, with event glue
automagically setup.
The code is splattered with a mix of
sizeof foo
sizeof (foo)
sizeof(foo)
Standardize on sizeof(foo) and add a syntax check rule to
enforce it
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This patch introduces a new event type for the QMP event
SUSPEND:
VIR_DOMAIN_EVENT_ID_PMSUSPEND
The event doesn't take any data, but considering there might
be reason for wakeup in future, the callback definition is:
typedef void
(*virConnectDomainEventSuspendCallback)(virConnectPtr conn,
virDomainPtr dom,
int reason,
void *opaque);
"reason" is unused currently, always passes "0".
This patch introduces a new event type for the QMP event
WAKEUP:
VIR_DOMAIN_EVENT_ID_PMWAKEUP
The event doesn't take any data, but considering there might
be reason for wakeup in future, the callback definition is:
typedef void
(*virConnectDomainEventWakeupCallback)(virConnectPtr conn,
virDomainPtr dom,
int reason,
void *opaque);
"reason" is unused currently, always passes "0".
This patch introduces a new event type for the QMP event
DEVICE_TRAY_MOVED, which occurs when the tray of a removable
disk is moved (i.e opened or closed):
VIR_DOMAIN_EVENT_ID_TRAY_CHANGE
The event's data includes the device alias and the reason
for tray status' changing, which indicates why the tray
status was changed. Thus the callback definition for the event
is:
enum {
VIR_DOMAIN_EVENT_TRAY_CHANGE_OPEN = 0,
VIR_DOMAIN_EVENT_TRAY_CHANGE_CLOSE,
\#ifdef VIR_ENUM_SENTINELS
VIR_DOMAIN_EVENT_TRAY_CHANGE_LAST
\#endif
} virDomainEventTrayChangeReason;
typedef void
(*virConnectDomainEventTrayChangeCallback)(virConnectPtr conn,
virDomainPtr dom,
const char *devAlias,
int reason,
void *opaque);
Overflow can be user-induced, so it deserves more than being called
an internal error. Note that in general, 32-bit platforms have
far more places to trigger this error (anywhere the public API
used 'unsigned long' but the other side of the connection is a
64-bit server); but some are possible on 64-bit platforms (where
the public API computes the product of two numbers).
* include/libvirt/virterror.h (VIR_ERR_OVERFLOW): New error.
* src/util/virterror.c (virErrorMsg): Translate it.
* src/libvirt.c (virDomainSetVcpusFlags, virDomainGetVcpuPinInfo)
(virDomainGetVcpus, virDomainGetCPUStats): Use it.
* daemon/remote.c (HYPER_TO_TYPE): Likewise.
* src/qemu/qemu_driver.c (qemuDomainBlockResize): Likewise.
The RPC code assumed that the array returned by the driver would be
fully populated; that is, ncpus on entry resulted in ncpus * return
value on exit. However, while we don't support holes in the middle
of ncpus, we do want to permit the case of ncpus on entry being
longer than the array returned by the driver (that is, it should be
safe for the caller to pass ncpus=128 on entry, and the driver will
stop populating the array when it hits max_id).
Additionally, a successful return implies that the caller will then
use virTypedParamArrayClear on the entire array; for this to not
free uninitialized memory, the driver must ensure that all skipped
entries are explicitly zeroed (the RPC driver did this, but not
the qemu driver).
There are now three cases:
server 0.9.10 and client 0.9.10 or newer: No impact - there were no
hypervisor drivers that supported cpu stats
server 0.9.11 or newer and client 0.9.10: if the client calls with
ncpus beyond the max, then the rpc call will fail on the client side
and disconnect the client, but the server is no worse for the wear
server 0.9.11 or newer and client 0.9.11: the server can return a
truncated array and the client will do just fine
I reproduced the problem by using a host with 2 CPUs, and doing:
virsh cpu-stats $dom --start 1 --count 2
* daemon/remote.c (remoteDispatchDomainGetCPUStats): Allow driver
to omit tail of array.
* src/remote/remote_driver.c (remoteDomainGetCPUStats):
Accommodate driver that omits tail of array.
* src/libvirt.c (virDomainGetCPUStats): Document this.
* src/qemu/qemu_driver.c (qemuDomainGetPercpuStats): Clear all
unpopulated entries.
Regression introduced in commit 7033c5f2, due to improper conversion
from snprintf to virAsprintf.
* daemon/remote.c (remoteDispatchAuthList): Check return value
correctly.
Sometimes, its easier to run children with 2>&1 in shell notation,
and just deal with stdout and stderr interleaved. This was already
possible for fd handling; extend it to also work when doing string
capture of a child process.
* docs/internals/command.html.in: Document this.
* src/util/command.c (virCommandSetErrorBuffer): Likewise.
(virCommandRun, virExecWithHook): Implement it.
* tests/commandtest.c (test14): Test it.
* daemon/remote.c (remoteDispatchAuthPolkit): Use new command
feature.
GCC complaints about uninitialized use of len, which however is only
used when errors != NULL and in that case len is always initialized.
It's trivial to silence this by always initializing len.
Using new function 'virTypedParameterArrayClear' to simplify block of codes.
* daemon/remote.c, src/remote/remote_driver.c: simplify codes.
Signed-off-by: Alex Jia <ajia@redhat.com>
Unlike other users of virTypedParameter with RPC, this interface
can return zero-filled entries because the interface assumes
2 dimensional array. We compress these entries out from the
server when generating the over-the-wire contents, then reconstitute
them in the client.
Signed-off-by: Eric Blake <eblake@redhat.com>
Several not uncommon issues can be diagnosed through pkcheck output, like
lack of/malfunctioning desktop agent, or lack of/malfunctioning polkit
dbus agent.
And hook it up for policykit auth. This allows virt-manager to detect
that the user clicked the policykit 'cancel' button and not throw
an 'authentication failed' error message at the user.
Convert daemon code to handle 64-bit pid_t (even though at the
moment, it is not compiled on mingw).
* daemon/remote.c (remoteDispatchAuthList)
(remoteDispatchAuthPolkit): Print pid_t via %lld.
Preparation for another patch that refactors common patterns
into the new file for fewer lines of code overall.
* src/util/util.h (virTypedParameterArrayClear): Move...
* src/util/virtypedparam.h: ...to new file.
(virTypedParameterArrayValidate, virTypedParameterAssign): New
prototypes.
* src/util/util.c (virTypedParameterArrayClear): Likewise.
* src/util/virtypedparam.c: New file.
* po/POTFILES.in: Mark file for translation.
* src/Makefile.am (UTIL_SOURCES): Build it.
* src/libvirt_private.syms (util.h): Split...
(virtypedparam.h): to new section.
(virkeycode.h): Sort.
* daemon/remote.c: Adjust callers.
* tools/virsh.c: Likewise.
To avoid a namespace clash with forthcoming identity APIs,
rename the virNet*GetLocalIdentity() APIs to have the form
virNet*GetUNIXIdentity()
* daemon/remote.c, src/libvirt_private.syms: Update
for renamed APIs
* src/rpc/virnetserverclient.c, src/rpc/virnetserverclient.h,
src/rpc/virnetsocket.c, src/rpc/virnetsocket.h: s/LocalIdentity/UNIXIdentity/
Most severe here is a latent (but currently untriggered) memory leak
if any hypervisor ever adds a string interface property; the
remainder are mainly cosmetic.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_BANDWIDTH_*): Move
macros closer to interface that uses them, and document type.
* src/libvirt.c (virDomainSetInterfaceParameters)
(virDomainGetInterfaceParameters): Formatting tweaks.
* daemon/remote.c (remoteDispatchDomainGetInterfaceParameters):
Avoid memory leak.
* src/libvirt_public.syms (LIBVIRT_0.9.9): Sort lines.
* src/libvirt_private.syms (domain_conf.h): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSetInterfaceParameters): Fix
comments, break long lines.
* daemon/remote.c: implement the server side support
* src/remote/remote_driver.c: implement the client side support
* src/remote/remote_protocol.x: definitions for the new entry points
* src/remote_protocol-structs: structure definitions
The RPC code had several latent memory leaks and an attempt to
free the wrong string, but thankfully nothing triggered them
(blkiotune was the only one returning a string, and always as
the last parameter). Also, our cleanups for rpcgen ended up
nuking a line of code that renders VIR_TYPED_PARAM_INT broken,
because it was the only use of 'i' in a function, even though
it was a member usage rather than a standalone declaration.
* daemon/remote.c (remoteSerializeTypedParameters): Free the
correct array element.
(remoteDispatchDomainGetSchedulerParameters)
(remoteDispatchDomainGetSchedulerParametersFlags)
(remoteDispatchDomainBlockStatsFlags)
(remoteDispatchDomainGetMemoryParameters): Don't leak strings.
* src/rpc/genprotocol.pl: Don't nuke member-usage of 'buf' or 'i'.
Support Block I/O Throttle setting and query to remote driver.
Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
The src/util/network.c file is a dumping ground for many different
APIs. Split it up into 5 pieces, along functional lines
- src/util/virnetdevbandwidth.c: virNetDevBandwidth type & helper APIs
- src/util/virnetdevvportprofile.c: virNetDevVPortProfile type & helper APIs
- src/util/virsocketaddr.c: virSocketAddr and APIs
- src/conf/netdev_bandwidth_conf.c: XML parsing / formatting
for virNetDevBandwidth
- src/conf/netdev_vport_profile_conf.c: XML parsing / formatting
for virNetDevVPortProfile
* src/util/network.c, src/util/network.h: Split into 5 pieces
* src/conf/netdev_bandwidth_conf.c, src/conf/netdev_bandwidth_conf.h,
src/conf/netdev_vport_profile_conf.c, src/conf/netdev_vport_profile_conf.h,
src/util/virnetdevbandwidth.c, src/util/virnetdevbandwidth.h,
src/util/virnetdevvportprofile.c, src/util/virnetdevvportprofile.h,
src/util/virsocketaddr.c, src/util/virsocketaddr.h: New pieces
* daemon/libvirtd.h, daemon/remote.c, src/conf/domain_conf.c,
src/conf/domain_conf.h, src/conf/network_conf.c,
src/conf/network_conf.h, src/conf/nwfilter_conf.h,
src/esx/esx_util.h, src/network/bridge_driver.c,
src/qemu/qemu_conf.c, src/rpc/virnetsocket.c,
src/rpc/virnetsocket.h, src/util/dnsmasq.h, src/util/interface.h,
src/util/iptables.h, src/util/macvtap.c, src/util/macvtap.h,
src/util/virnetdev.h, src/util/virnetdevtap.c,
tools/virsh.c: Update include files
Send and receive string typed parameters across RPC. This also
completes the back-compat mentioned in the previous patch - the
only time we have an older client talking to a newer server is
if RPC is in use, so filtering out strings during RPC prevents
returning an unknown type to the older client.
* src/remote/remote_protocol.x (remote_typed_param_value): Add
another union value.
* daemon/remote.c (remoteDeserializeTypedParameters): Handle
strings on rpc.
(remoteSerializeTypedParameters): Likewise; plus filter out
strings when replying to older clients. Adjust callers.
* src/remote/remote_driver.c (remoteFreeTypedParameters)
(remoteSerializeTypedParameters)
(remoteDeserializeTypedParameters): Handle strings on rpc.
* src/rpc/gendispatch.pl: Properly clean up typed arrays.
* src/remote_protocol-structs: Update.
Based on an initial patch by Hu Tao, with feedback from
Daniel P. Berrange.
Signed-off-by: Eric Blake <eblake@redhat.com>
Since it needs to access file descriptors passed in the msg,
the RPC driver for virDomainOpenGraphics needs to be manually
implemented.
* daemon/remote.c: RPC server dispatcher
* src/remote/remote_driver.c: RPC client dispatcher
* src/remote/remote_protocol.x: Define protocol
The RPC server classes are extended to allow FDs to be received
from clients with calls. There is not currently any way for a
procedure to pass FDs back to the client with replies
* daemon/remote.c, src/rpc/gendispatch.pl: Change virNetMessageHeaderPtr
param to virNetMessagePtr in dispatcher impls
* src/rpc/virnetserver.c, src/rpc/virnetserverclient.c,
src/rpc/virnetserverprogram.c, src/rpc/virnetserverprogram.h:
Extend to support FD passing
If a disk source gets dropped because it is not accessible,
mgmt application might want to be informed about this. Therefore
we need to emit an event. The event presented in this patch
is however a bit superset of what written above. The reason is simple:
an intention to be easily expanded, e.g. on 'user ejected disk
in guest' events. Therefore, callback gets source string and disk alias
(which should be unique among a domain) and reason (an integer);
The libvirtd daemon had a few crude system tap probes. Some of
these were broken during the RPC rewrite. The new modular RPC
code is structured in a way that allows much more effective
tracing. Instead of trying to hook up the original probes,
define a new set of probes for the RPC and event code.
The master probes file is now src/probes.d. This contains
probes for virNetServerClientPtr, virNetClientPtr, virSocketPtr
virNetTLSContextPtr and virNetTLSSessionPtr modules. Also add
probes for the poll event loop.
The src/dtrace2systemtap.pl script can convert the probes.d
file into a libvirt_probes.stp file to make use from systemtap
much simpler.
The src/rpc/gensystemtap.pl script can generate a set of
systemtap functions for translating RPC enum values into
printable strings. This works for all RPC header enums (program,
type, status, procedure) and also the authentication enum
The PROBE macro will automatically generate a VIR_DEBUG
statement, so any place with a PROBE can remove any existing
manual DEBUG statements.
* daemon/libvirtd.stp, daemon/probes.d: Remove obsolete probing
* daemon/libvirtd.h: Remove probe macros
* daemon/Makefile.am: Remove all probe buildings/install
* daemon/remote.c: Update authentication probes
* src/dtrace2systemtap.pl, src/rpc/gensystemtap.pl: Scripts
to generate STP files
* src/internal.h: Add probe macros
* src/probes.d: Master list of probes
* src/rpc/virnetclient.c, src/rpc/virnetserverclient.c,
src/rpc/virnetsocket.c, src/rpc/virnettlscontext.c,
src/util/event_poll.c: Insert probe points, removing any
DEBUG statements that duplicate the info
Bug introduced in commit 675464b. On an OOM, this would try to
dereference a char* and free the contents as a pointer, which is
doomed to failure.
Adding a syntax check will prevent mistakes like this in the future.
* cfg.mk (sc_prohibit_internal_functions): New syntax check.
(exclude_file_name_regexp--sc_prohibit_internal_functions): Add
exemptions.
* daemon/remote.c (remoteRelayDomainEventIOError)
(remoteRelayDomainEventIOErrorReason)
(remoteRelayDomainEventGraphics, remoteRelayDomainEventBlockJob):
Use correct free function.
remoteRelayDomainEventBlockJob, remoteRelayDomainEventIOError,
remoteRelayDomainEventIOErrorReason and remoteRelayDomainEventGraphics
were using const string directly in rpc structure, before calling
remoteDispatchDomainEventSend(). But that routine now frees up all
the pointed allocated memory from the rpc structure and we end up
with a double free.
This now strdup() all the strings passed and provide mem_error goto
labels to be used when an allocation error occurs.
Note that the cleanup isn't completely finished because all relaying
function also call make_nonnull_domain() which also allocate a string
and never handle the error case. This patches doesn't try to address
this as this is only error correctness a priori and touches far more
functions in this module:
* daemon/remote.c: fix string allocations and memory error handling
for remoteRelayDomainEventBlockJob, remoteRelayDomainEventIOError,
remoteRelayDomainEventIOErrorReason and remoteRelayDomainEventGraphics
Commit 2c85644b0b attempted to
fix a problem with tracking RPC messages from streams by doing
- if (msg->header.type == VIR_NET_REPLY) {
+ if (msg->header.type == VIR_NET_REPLY ||
+ (msg->header.type == VIR_NET_STREAM &&
+ msg->header.status != VIR_NET_CONTINUE)) {
client->nrequests--;
In other words any stream packet, with status NET_OK or NET_ERROR
would cause nrequests to be decremented. This is great if the
packet from from a synchronous virStreamFinish or virStreamAbort
API call, but wildly wrong if from a server initiated abort.
The latter resulted in 'nrequests' being decremented below zero.
This then causes all I/O for that client to be stopped.
Instead of trying to infer whether we need to decrement the
nrequests field, from the message type/status, introduce an
explicit 'bool tracked' field to mark whether the virNetMessagePtr
object is subject to tracking.
Also add a virNetMessageClear function to allow a message
contents to be cleared out, without adversely impacting the
'tracked' field as a naive memset() would do
* src/rpc/virnetmessage.c, src/rpc/virnetmessage.h: Add
a 'bool tracked' field and virNetMessageClear() API
* daemon/remote.c, daemon/stream.c, src/rpc/virnetclientprogram.c,
src/rpc/virnetclientstream.c, src/rpc/virnetserverclient.c,
src/rpc/virnetserverprogram.c: Switch over to use
virNetMessageClear() and pass in the 'bool tracked' value
when creating messages.
When dispatching domain events we will create an XDR struct
containing the event info. Some of this data may be allocated
on the heap and so must be freed. The graphics event dispatcher
had a broken attempt to free one field, but missed others. All
the events have a dom->name string that needs freeing. The code
should have used the xdr_free() procedure for doing all this
* daemon/remote.c: Use xdr_free after dispatching events
Every active stream results in a reference being held on the
virNetServerClientPtr object. This meant that if a client quit
with any streams active, although all I/O was stopped the
virNetServerClientPtr object would leak. This causes libvirtd
to leak any file handles associated with open streams when a
client quit
To fix this, when we call virNetServerClientClose there is a
callback invoked which lets the daemon release the streams
and thus the extra references
* daemon/remote.c: Add a hook to close all streams
* daemon/stream.c, daemon/stream.h: Add API for releasing
all streams
* src/rpc/virnetserverclient.c, src/rpc/virnetserverclient.h:
Allow registration of a hook to trigger when closing client
When an operation started by virDomainBlockPull completes (either with
success or with failure), raise an event to indicate the final status.
This API allow users to avoid polling on virDomainGetBlockJobInfo if
they would prefer to use an event mechanism.
* daemon/remote.c: Dispatch events to client
* include/libvirt/libvirt.h.in: Define event ID and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
src/libvirt_private.syms: Extend API to handle the new event
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
for block_stream completion and emit a libvirt block pull event
* src/remote/remote_driver.c: Receive and dispatch events to application
* src/remote/remote_protocol.x: Wire protocol definition for the event
* src/remote_protocol-structs: structure definitions for protocol verification
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c: Watch for BLOCK_STREAM_COMPLETED event
from QEMU monitor
The generator can handle everything except virDomainGetBlockJobInfo().
* src/remote/remote_protocol.x: provide defines for the new entry points
* src/remote/remote_driver.c daemon/remote.c: implement the client and
server side for virDomainGetBlockJobInfo.
* src/remote_protocol-structs: structure definitions for protocol verification
* src/rpc/gendispatch.pl: Permit some unsigned long parameters
There were two API in driver.c that were silently masking flags
bits prior to calling out to the drivers, and several others
that were explicitly masking flags bits. This is not
forward-compatible - if we ever have that many flags in the
future, then talking to an old server that masks out the
flags would be indistinguishable from talking to a new server
that can honor the flag. In general, libvirt.c should forward
_all_ flags on to drivers, and only the drivers should reject
unknown flags.
In the case of virDrvSecretGetValue, the solution is to separate
the internal driver callback function to have two parameters
instead of one, with only one parameter affected by the public
API. In the case of virDomainGetXMLDesc, it turns out that
no one was ever mixing VIR_DOMAIN_XML_INTERNAL_STATUS with
the dumpxml path in the first place; that internal flag was
only used in saving and restoring state files, which happened
to be in functions internal to a single file, so there is no
mixing of the internal flag with a public flags argument.
Additionally, virDomainMemoryStats passed a flags argument
over RPC, but not to the driver.
* src/driver.h (VIR_DOMAIN_XML_FLAGS_MASK)
(VIR_SECRET_GET_VALUE_FLAGS_MASK): Delete.
(virDrvSecretGetValue): Separate out internal flags.
(virDrvDomainMemoryStats): Provide missing flags argument.
* src/driver.c (verify): Drop unused check.
* src/conf/domain_conf.h (virDomainObjParseFile): Delete
declaration.
(virDomainXMLInternalFlags): Move...
* src/conf/domain_conf.c: ...here. Delete redundant include.
(virDomainObjParseFile): Make static.
* src/libvirt.c (virDomainGetXMLDesc, virSecretGetValue): Update
clients.
(virDomainMemoryPeek, virInterfaceGetXMLDesc)
(virDomainMemoryStats, virDomainBlockPeek, virNetworkGetXMLDesc)
(virStoragePoolGetXMLDesc, virStorageVolGetXMLDesc)
(virNodeNumOfDevices, virNodeListDevices, virNWFilterGetXMLDesc):
Don't mask unknown flags.
* src/interface/netcf_driver.c (interfaceGetXMLDesc): Reject
unknown flags.
* src/secret/secret_driver.c (secretGetValue): Update clients.
* src/remote/remote_driver.c (remoteSecretGetValue)
(remoteDomainMemoryStats): Likewise.
* src/qemu/qemu_process.c (qemuProcessGetVolumeQcowPassphrase):
Likewise.
* src/qemu/qemu_driver.c (qemudDomainMemoryStats): Likewise.
* daemon/remote.c (remoteDispatchDomainMemoryStats): Likewise.
The dispatch for the CLOSE RPC call was invoking the method
virNetServerClientClose(). This caused the client connection
to be immediately terminated. This meant the reply to the
final RPC message was never sent. Prior to the RPC rewrite
we merely flagged the connection for closing, and actually
closed it when the next RPC call dispatch had completed.
* daemon/remote.c: Flag connection for a delayed close
* daemon/stream.c: Update to use new API for closing
failed connection
* src/rpc/virnetserverclient.c, src/rpc/virnetserverclient.h:
Add support for a delayed connection close. Rename the
virNetServerClientMarkClose method to virNetServerClientImmediateClose
to clarify its semantics
Version 1.3 of <sys/sdt.h> uses this macro
#define STAP_CAST(t) (size_t)t
that breaks like this if t is a function
remote.c:1775: error: cast from function call of type 'const char *'
to non-matching type 'long unsigned int' [-Wbad-function-cast]
For that to work it should probably look like this
#define STAP_CAST(t) ((size_t)(t))
In systemtap 1.4 this was completely rewritten.
Anyway, before commit df0b57a95a t was always a variable, but now
also a function is used here, namely virNetSASLSessionGetIdentity.
Use an intermediate variable to avoid this problem.
This guts the libvirtd daemon, removing all its networking and
RPC handling code. Instead it calls out to the new virServerPtr
APIs for all its RPC & networking work
As a fallout all libvirtd daemon error reporting now takes place
via the normal internal error reporting APIs. There is no need
to call separate error reporting APIs in RPC code, nor should
code use VIR_WARN/VIR_ERROR for reporting fatal problems anymore.
* daemon/qemu_dispatch_*.h, daemon/remote_dispatch_*.h: Remove
old generated dispatcher code
* daemon/qemu_dispatch.h, daemon/remote_dispatch.h: New dispatch
code
* daemon/dispatch.c, daemon/dispatch.h: Remove obsoleted code
* daemon/remote.c, daemon/remote.h: Rewrite for new dispatch
APIs
* daemon/libvirtd.c, daemon/libvirtd.h: Remove all networking
code
* daemon/stream.c, daemon/stream.h: Update for new APIs
* daemon/Makefile.am: Link to libvirt-net-rpc-server.la
We already have a public virDomainPinVcpu, which implies that
Pin and Vcpu are treated as separate words. Unreleased commit
e261987c introduced virDomainGetVcpupinInfo as the first public
API that used Vcpupin, although we had prior internal uses of
that spelling. For consistency, change the spelling to be two
words everywhere, regardless of whether pin comes first or last.
* daemon/remote.c: Treat vcpu and pin as separate words.
* include/libvirt/libvirt.h.in: Likewise.
* src/conf/domain_conf.c: Likewise.
* src/conf/domain_conf.h: Likewise.
* src/driver.h: Likewise.
* src/libvirt.c: Likewise.
* src/libvirt_private.syms: Likewise.
* src/libvirt_public.syms: Likewise.
* src/libxl/libxl_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/xen/xend_internal.c: Likewise.
* tools/virsh.c: Likewise.
* src/remote/remote_protocol.x: Likewise.
* src/remote_protocol-structs: Likewise.
Suggested by Matthias Bolte.
Integer overflow and remote code are never a nice mix.
This has existed since commit 56cd414.
* src/libvirt.c (virDomainGetVcpus): Reject overflow up front.
* src/remote/remote_driver.c (remoteDomainGetVcpus): Avoid overflow
on sending rpc.
* daemon/remote.c (remoteDispatchDomainGetVcpus): Avoid overflow on
receiving rpc.
Removes special case code from the generator and handle additional
methods.
The generated version of remoteDispatchDomainPinVcpu(Flags) has no
length check, but this check was useless anyway as it was applied to
data that was already deserialized from its XDR form.
When an operation started by virDomainBlockPullAll completes (either with
success or with failure), raise an event to indicate the final status. This
allows an API user to avoid polling on virDomainBlockPullInfo if they would
prefer to use the event mechanism.
* daemon/remote.c: Dispatch events to client
* include/libvirt/libvirt.h.in: Define event ID and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
src/libvirt_private.syms: Extend API to handle the new event
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
for block_stream completion and emit a libvirt block pull event
* src/remote/remote_driver.c: Receive and dispatch events to application
* src/remote/remote_protocol.x: Wire protocol definition for the event
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c: Watch for BLOCK_STREAM_COMPLETED event
from QEMU monitor
Signed-off-by: Adam Litke <agl@us.ibm.com>
The generator can handle DomainBlockPullAll and DomainBlockPullAbort.
DomainBlockPull and DomainBlockPullInfo must be written by hand.
* src/remote/remote_protocol.x: provide defines for the new entry points
* src/remote/remote_driver.c daemon/remote.c: implement the client and
server side
* src/remote_protocol-structs: structure definitions for protocol verification
Signed-off-by: Adam Litke <agl@us.ibm.com>
Remove some special case code that took care of mapping hyper to the
correct C types.
As the list of procedures that is allowed to map hyper to long is fixed
put it in the generator instead annotations in the .x files. This
results in simpler .x file parsing code.
Use macros for hyper to long assignments that perform overflow checks
when long is smaller than hyper. Map hyper to long long by default.
Suggested by Eric Blake.
This introduces a new domain
VIR_DOMAIN_EVENT_ID_CONTROL_ERROR
Which uses the existing generic callback
typedef void (*virConnectDomainEventGenericCallback)(virConnectPtr conn,
virDomainPtr dom,
void *opaque);
This event is intended to be emitted when there is a failure in
some part of the domain virtualization system. Whether the domain
continues to run/exist after the failure is an implementation
detail specific to the hypervisor.
The idea is that with some types of failure, hypervisors may
prefer to leave the domain running in a "degraded" mode of
operation. For example, if something goes wrong with the QEMU
monitor, it is possible to leave the guest OS running quite
happily. The mgmt app will simply loose the ability todo various
tasks. The mgmt app can then choose how/when to deal with the
failure that occured.
* daemon/remote.c: Dispatch of new event
* examples/domain-events/events-c/event-test.c: Demo catch
of event
* include/libvirt/libvirt.h.in: Define event ID and callback
* src/conf/domain_event.c, src/conf/domain_event.h: Internal
event handling
* src/remote/remote_driver.c: Receipt of new event from daemon
* src/remote/remote_protocol.x: Wire protocol for new event
* src/remote_protocol-structs: add new event for checks
The current virDomainMigrateFinish3 method signature attempts to
distinguish two types of errors, by allowing return with ret== 0,
but ddomain == NULL, to indicate a failure to start the guest.
This is flawed, because when ret == 0, there is no way for the
virErrorPtr details to be sent back to the client.
Change the signature of virDomainMigrateFinish3 so it simply
returns a virDomainPtr, in the same way as virDomainMigrateFinish2
The disk locking code will protect against the only possible
failure mode this doesn't account for (loosing conenctivity to
libvirtd after Finish3 starts the CPUs, but before the client
sees the reply for Finish3).
* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Change
virDomainMigrateFinish3 to return a virDomainPtr instead of int
* src/remote/remote_driver.c, src/remote/remote_protocol.x,
daemon/remote.c, src/qemu/qemu_driver.c, src/qemu/qemu_migration.c:
Update for API change
The virDomainMigratePerform3 currently has a single URI parameter
whose meaning varies. It is either
- A QEMU migration URI (normal migration)
- A libvirtd connection URI (peer2peer migration)
Unfortunately when using peer2peer migration, without also
using tunnelled migration, it is possible that both URIs are
required.
This adds a second URI parameter to the virDomainMigratePerform3
method, to cope with this scenario. Each parameter how has a fixed
meaning.
NB, there is no way to actually take advantage of this yet,
since virDomainMigrate/virDomainMigrateToURI do not have any
way to provide the 2 separate URIs
* daemon/remote.c, src/remote/remote_driver.c,
src/remote/remote_protocol.x, src/remote_protocol-structs: Add
the second URI parameter to perform3 message
* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Add
the second URI parameter to Perform3 method
* src/libvirt_internal.h, src/qemu/qemu_migration.c,
src/qemu/qemu_migration.h: Update to handle URIs correctly
This extends the v3 migration protocol such that the
virDomainMigrateBegin3 and virDomainMigratePerform3
methods accept an application supplied XML config for
the target VM.
If the 'xmlin' parameter is NULL, then Begin3 uses the
current guest XML as normal. A driver implementing the
Begin3 method should either reject all non-NULL 'xmlin'
parameters, or strictly validate that the app supplied
XML does not change guest ABI.
The Perform3 method also needed the xmlin parameter to
cope with the Peer2Peer migration sequence.
NB it is not yet possible to use this capability since
neither of the public virDomainMigrate/virDomainMigrateToURI
methods have a way to pass in XML.
* daemon/remote.c, src/remote/remote_driver.c,
src/remote/remote_protocol.x, src/remote_protocol-structs:
Add 'remote_string xmlin' parameter to begin3/perform3
RPC messages
* src/libvirt.c, src/driver.h, src/libvirt_internal.h: Add
'const char *xmlin' parameter to Begin3/Perform3 methods
* src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
src/qemu/qemu_migration.h: Pass xmlin parameter around
migration methods
virStreamNew needs to dispatch the error that virGetStream reports
on failure.
remoteCreateClientStream can fail due to virStreamNew or due to
VIR_ALLOC. Report OOM error for VIR_ALLOC failure to report errors
in all error cases.
Remove OOM error reporting from remoteCreateClientStream callers.
We were 31/73 on whether to translate; since less than 50% translated
and since VIR_INFO is less than VIR_WARN which also doesn't translate,
this makes sense.
* cfg.mk (sc_prohibit_gettext_markup): Add VIR_INFO, since it
falls between WARN and DEBUG.
* daemon/libvirtd.c (qemudDispatchSignalEvent, remoteCheckAccess)
(qemudDispatchServer): Adjust offenders.
* daemon/remote.c (remoteDispatchAuthPolkit): Likewise.
* src/network/bridge_driver.c (networkReloadIptablesRules)
(networkStartNetworkDaemon, networkShutdownNetworkDaemon)
(networkCreate, networkDefine, networkUndefine): Likewise.
* src/qemu/qemu_driver.c (qemudDomainDefine)
(qemudDomainUndefine): Likewise.
* src/storage/storage_driver.c (storagePoolCreate)
(storagePoolDefine, storagePoolUndefine, storagePoolStart)
(storagePoolDestroy, storagePoolDelete, storageVolumeCreateXML)
(storageVolumeCreateXMLFrom, storageVolumeDelete): Likewise.
* src/util/bridge.c (brProbeVnetHdr): Likewise.
* po/POTFILES.in: Drop src/util/bridge.c.
These VIR_XXXX0 APIs make us confused, use the non-0-suffix APIs instead.
How do these coversions works? The magic is using the gcc extension of ##.
When __VA_ARGS__ is empty, "##" will swallow the "," in "fmt," to
avoid compile error.
example: origin after CPP
high_level_api("%d", a_int) low_level_api("%d", a_int)
high_level_api("a string") low_level_api("a string")
About 400 conversions.
8 special conversions:
VIR_XXXX0("") -> VIR_XXXX("msg") (avoid empty format) 2 conversions
VIR_XXXX0(string_literal_with_%) -> VIR_XXXX(%->%%) 0 conversions
VIR_XXXX0(non_string_literal) -> VIR_XXXX("%s", non_string_literal)
(for security) 6 conversions
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
In preparation for removing generated files, it is necessary
to tell automake that the generated files must be distributed
but not directly compiled (since they are included into the
body of a larger .c file that is compiled). Hence, even though
these files are code and not headers in the strict sense of
the word, it is easier to rename them to .h for automake's sake.
* daemon/remote_client_bodies.c: Rename to .h.
* daemon/qemu_client_bodies.c: Likewise.
* src/remote/remote_client_bodies.c: Likewise.
* src/remote/qemu_client_bodies.c: Likewise.
* daemon/Makefile.am (remote_dispatch_bodies.c)
(qemu_dispatch_bodies.c): Rename to .h.
(remote.c, EXTRA_DIST): Reflect rename.
* daemon/remote.c: Likewise.
* daemon/remote_generator.pl: Likewise.
* src/Makefile.am (remote/remote_driver.c): Likewise.
* src/remote/remote_driver.c: Likewise.
* po/POTFILES.in: Likewise.
* cfg.mk (exclude_file_name_regexp--sc_require_config_h)
(exclude_file_name_regexp--sc_require_config_h_first)
(exclude_file_name_regexp--sc_prohibit_empty_lines_at_EOF):
Likewise.
This patch just covers the simple functions without explicit return
values. There is more to be handled.
The generator collects the members of the XDR argument structs and uses
this information to generate the function bodies.
Exclude the generated files from offending syntax-checks.
Suggested by Richard W.M. Jones
Clang found three instances of uninitialized use of nparams in
the cleanup path. Unfortunately, one is a false positive: clang
couldn't see that ret->params.params_val is guaranteed to be
NULL unless allocated within a function, and that nparams is
guaranteed to be assigned prior to the allocation; hoisting the
assignment to nparams to be earlier in the function shuts up
that false positive. But two of the reports also happened to
highlight a real bug - the error path can dereference NULL.
Regression introduced in commit 158ba873.
* daemon/remote.c (remoteDispatchDomainGetMemoryParameters)
(remoteDispatchDomainGetBlkioParameters): Don't clear fields if
array was not allocated.
(remoteDispatchDomainGetSchedulerParameters): Initialize nparams
earlier.
Replace some occurrances of
virDomainPtr domain;
virNetworkPtr network;
With
virDomainPtr dom;
virNetworkPtr net;
* daemon/remote.c: Fix variable naming to follow standard
Replace cases of
type = virConnectGetType(conn);
if (type == NULL)
goto cleanup;
With
if (!(type = virConnectGetType(conn)))
goto cleanup;
* daemon/remote.c: Write error checks in compat form
Replace all occurrances of
if (....) {
goto cleanup;
}
With
if (.....)
goto cleanup;
to save one line of code
* daemon/remote.c: Remove curly braces on single line conditionals
The libvirt APIs reserve any negative value for indicating an
error. Thus checks
if (virXXXX() == -1)
Should instead be
if (virXXXX() < 0)
* daemon/remote.c: s/ == -1/ < 0/
The dispatcher functions have numerous places where they
return to the caller. This leads to duplicated cleanup
code, often resulting in memory leaks. It makes it harder
to ensure that errors are dispatched before freeing objects,
which may overwrite the original error.
The standard pattern is now
remoteDispatchXXX(...) {
int rv = -1;
....
if (XXX < 0)
goto cleanup;
...
if (XXXX < 0)
goto cleanup;
...
rv = 0;
cleanup:
if (rv < 0)
remoteDispatchError(rerr);
...free all other stuff..
return rv;
}
* daemon/remote.c: Centralize all cleanup paths
* daemon/stream.c: s/remoteDispatchConnError/remoteDispatchError/
* daemon/dispatch.c, daemon/dispatch.h: Replace
remoteDispatchConnError with remoteDispatchError
removing unused virConnectPtr
The daemon dispatcher code had an obsolete macro
#define REMOTE_DEBUG(fmt, ...) VIR_DEBUG(fmt, __VA_ARGS__)
This can be trivially removed
* daemon/remote.c: s/REMOTE_DEBUG/VIR_DEBUG/
Many functions did not check for whether a connection was
open. Replace the macro which obscures control flow, with
explicit checks, and ensure all dispatcher code has checks.
* daemon/remote.c: Add connection checks
A lot of code in libvirtd's dispatcher used the style
dom = get_nonnull_domain (conn, args->dom);
Instead of the normal libvirt style
dom = get_nonnull_domain(conn, args->dom);
* daemon/remote.c: Remove all whitelist before function brackets
Commit f44bfb7 was supposed to make sure no additional libvirt API (esp.
*Free) is called before remoteDispatchConnError() is called on error.
However, the patch missed two instances.
Child processes don't always reach _exit(); if they die from a
signal, then any messages should still be accurate. Most users
either expect a 0 status (thankfully, if status==0, then
WIFEXITED(status) is true and WEXITSTATUS(status)==0 for all
known platforms) or were filtering on WIFEXITED before printing
a status, but a few were missing this check. Additionally,
nwfilter_ebiptables_driver was making an assumption that works
on Linux (where WEXITSTATUS shifts and WTERMSIG just masks)
but fails on other platforms (where WEXITSTATUS just masks and
WTERMSIG shifts).
* src/util/command.h (virCommandTranslateStatus): New helper.
* src/libvirt_private.syms (command.h): Export it.
* src/util/command.c (virCommandTranslateStatus): New function.
(virCommandWait): Use it to also diagnose status from signals.
* src/security/security_apparmor.c (load_profile): Likewise.
* src/storage/storage_backend.c
(virStorageBackendQEMUImgBackingFormat): Likewise.
* src/util/util.c (virExecDaemonize, virRunWithHook)
(virFileOperation, virDirCreate): Likewise.
* daemon/remote.c (remoteDispatchAuthPolkit): Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c (ebiptablesExecCLI):
Likewise.
Bug https://bugzilla.redhat.com/show_bug.cgi?id=689374 reported libvirtd
crash during error dispatch.
The reason is that libvirtd uses remoteDispatchConnError() with non-NULL
conn parameter which means that virConnGetLastError() is used instead of
its thread safe replacement virGetLastError().
So when several libvirtd threads are reporting errors at the same time,
the errors can get mixed or corrupted or in case of bad luck libvirtd
itself crashes.
Since Daniel B. is going to rewrite this code from scratch on top of his
RPC infrastructure, I tried to come up with a minimal fix. Thus,
remoteDispatchConnError() now just ignores its conn argument and always
calls virGetLastError(). However, several callers had to be touched as
well, since no libvirt API is allowed to be called before dispatching
the error. Doing so would reset the error and we would have nothing to
dispatch. As a result of that, the code is not very nice but that
doesn't really make daemon/remote.c worse than it is now :-) And it will
all die soon, which is good.
The bug report also contains a reproducer in C which detects both mixed
up error messages and libvirtd crash. Before this patch, I was able to
crash libvirtd in about 20 seconds up to 3 minutes depending on number
of CPU cores (more is better) and luck.
Done mechanically with:
$ git grep -l '\bDEBUG0\? *(' | xargs -L1 sed -i 's/\bDEBUG0\? *(/VIR_&/'
followed by manual deletion of qemudDebug in daemon/libvirtd.c, along
with a single 'make syntax-check' fallout in the same file, and the
actual deletion in src/util/logging.h.
* src/util/logging.h (DEBUG, DEBUG0): Delete.
* daemon/libvirtd.h (qemudDebug): Likewise.
* global: Change remaining clients over to VIR_DEBUG counterpart.
To make it easier to investigate problems with async event
delivery, add two more debugging lines
* daemon/remote.c: Debug when an event is queued for dispatch
* src/remote/remote_driver.c: Debug when an event is received
for processing
This provides an implementation of the virDomainOpenConsole
API for the remote driver client and server.
* daemon/remote.c: Server side impl
* src/remote/remote_driver.c: Client impl
* src/remote/remote_protocol.x: Wire definition
Commit e8066d53 broke the build with polkit0:
remote.c: In function 'remoteDispatchAuthPolkit':
remote.c:4177: error: 'rv' undeclared (first use in this function)
Add missing identifier.
Revert most of commit a8b5f9bd27.
The audit hooks will be re-added directly in the QEMU driver code
in a future commit
* daemon/remote.c: Remove all audit logging hooks
* src/qemu/qemu_driver.c: Remove all audit logging hooks
With SystemTap 1.0 a part of the generated macros in probes.h
expands to:
volatile __typeof__(((name))) arg2 = (name);
GCC reports an 'invalid initialize' error when name has type
char[]. Therfore, add casts to char* to avoid this.
It is useful to know where the client is connecting from,
so include the socket address in probe data.
* daemon/libvirtd.h: Use virSocketAddr for storing client
address and keep printable address handy for logging
* daemon/libvirtd.c: Include socket address in client
connect/disconnect probes
* daemon/probes.d: Add socket address to probes
* examples/systemtap/client.stp: Print socket address
* src/util/network.h: Add sockaddr_un to virSocketAddr union
Adds initial support for dtrace static probes in libvirtd
daemon, assuming use of systemtap dtrace compat shim on
Linux. The probes are inserted for network client connect,
disconnect, TLS handshake states and authentication protocol
states.
This can be tested by running the xample program and then
attempting to connect with any libvirt client (virsh,
virt-manager, etc).
# stap examples/systemtap/client.stp
Client fd=44 connected readonly=0
Client fd=44 auth polkit deny pid:24997,uid:500
Client fd=44 disconnected
Client fd=46 connected readonly=1
Client fd=46 auth sasl allow test
Client fd=46 disconnected
The libvirtd.stp file should also really not be required,
since it is duplicated info that is already available in
the main probes.d definition file. A script to autogenerate
the .stp file is needed, either in libvirtd tree, or better
as part of systemtap itself.
* Makefile.am: Add examples/systemtap subdir
* autobuild.sh: Disable dtrace for mingw32
* configure.ac: Add check for dtrace
* daemon/.gitignore: Ignore generated dtrace probe file
* daemon/Makefile.am: Build dtrace probe header & object
files
* daemon/libvirtd.stp: SystemTAP convenience probeset
* daemon/libvirtd.c: Add connect/disconnect & TLS probes
* daemon/remote.c: Add SASL and PolicyKit auth probes
* daemon/probes.d: Master probe definition
* daemon/libvirtd.h: Add convenience macro for probes
so that compilation is a no-op when dtrace is not available
* examples/systemtap/Makefile.am, examples/systemtap/client.stp
Example systemtap script using dtrace probe markers
* libvirt.spec.in: Enable dtrace on F13/RHEL6
* mingw32-libvirt.spec.in: Force disable dtrace
The addrToString functionality is now available via the
virSocketFormatAddrFull method.
* daemon/remote.c, src/remote/remote_driver.c: Remove
addrToString methods
If getnameinfo() with NI_NUMERICHOST set fails, there are no
grounds to expect inet_ntop to succeed, since these calls
are functionally equivalent. Remove useless inet_ntop code
in the getnameinfo() error path.
* daemon/remote.c, src/remote/remote_driver.c: Remove
calls to inet_ntop
Most operations are audited at the libvirtd level; auditing in
src/libvirt.c would result in two audit entries per operation (one in
the client, one in libvirtd).
The only exception is a domain stopping of its own will (e.g. because
the user clicks on "shutdown" inside the interface). There can often be
no client connected at the time the domain stops, so libvirtd does not
have any virConnectPtr object on which to attach an event watch. This
patch therefore adds auditing directly inside the qemu driver (other
drivers are not supported).
