Commit Graph

60 Commits

Author SHA1 Message Date
Osier Yang
79306739db qemu: Remove bogus error codes for NUMA memory tuning
This is no code between virSaveLastError and virGetLastError will
set an error, remove the bogus codes.
2011-06-27 23:20:15 +08:00
Eric Blake
c4c59e7228 Revert "Asynchronous event for BlockPull completion"
This reverts commit 12cd77a0c5.

Conflicts:

	python/libvirt-override-virConnect.py
	python/libvirt-override.c
	src/remote/remote_protocol.x
2011-06-24 08:41:24 -06:00
Eric Blake
98d83094a0 build: fix NUMA build on RHEL 5
Use NUMA's older nodemask_t (fixed-size map) rather than the newer
'struct bitmask' (variable-size) in order to still compile on RHEL 5,
with its numactl-devel-0.9.8.

* src/qemu/qemu_process.c [HAVE_NUMA]: Prefer back-compat mode.
(qemuProcessInitNumaMemoryPolicy): Use older nodemask_t.
2011-06-24 08:24:10 -06:00
Daniel P. Berrange
c0cd292933 Add missing translation of error message from QEMU reboot patch
* src/qemu/qemu_process.c: Add missing _(...)
2011-06-24 12:25:00 +01:00
Daniel P. Berrange
3ba937da42 Allow automatic kill of guests when a connection is closed
If an application is using libvirt + KVM as a piece of its
internal infrastructure to perform a specific task, it can
be desirable to guarentee the VM dies when the virConnectPtr
disconnects from libvirtd. This ensures the app can't leak
any VMs it was using. Adding VIR_DOMAIN_START_AUTOKILL as
a flag when starting guests enables this to be done.

* include/libvirt/libvirt.h.in: All VIR_DOMAIN_START_AUTOKILL
* src/qemu/qemu_driver.c: Support automatic killing of guests
  upon connection close
* tools/virsh.c: Add --autokill flag to 'start' and 'create'
  commands
2011-06-24 12:15:10 +01:00
Daniel P. Berrange
558b7fd03d Add infrastructure to automatically destroy guests when a connection closes
Sometimes it is useful to be able to automatically destroy a guest when
a connection is closed. For example, kill an incoming migration if
the client managing the migration dies. This introduces a map between
guest 'uuid' strings and virConnectPtr objects. When a connection is
closed, any associated guests are killed off.

* src/qemu/qemu_conf.h: Add autokill hash table to qemu driver
* src/qemu/qemu_process.c, src/qemu/qemu_process.h: Add APIs
  for performing autokill of guests associated with a connection
* src/qemu/qemu_driver.c: Initialize autodestroy map
2011-06-24 12:15:10 +01:00
Daniel P. Berrange
42f43592be Support reboots with the QEMU driver
For controlled shutdown we issue a 'system_powerdown' command
to the QEMU monitor. This triggers an ACPI event which (most)
guest OS wire up to a controlled shutdown. There is no equiv
ACPI event to trigger a controlled reboot. This patch attempts
to fake a reboot.

 - In qemuDomainObjPrivatePtr we have a bool fakeReboot
   flag.
 - The virDomainReboot method sets this flag and then
   triggers a normal 'system_powerdown'.
 - The QEMU process is started with '-no-shutdown'
   so that the guest CPUs pause when it powers off the
   guest
 - When we receive the 'POWEROFF' event from QEMU JSON
   monitor if fakeReboot is not set we invoke the
   qemuProcessKill command and shutdown continues
   normally
 - If fakeReboot was set, we spawn a background thread
   which issues 'system_reset' to perform a warm reboot
   of the guest hardware. Then it issues 'cont' to
   start the CPUs again

* src/qemu/qemu_command.c: Add -no-shutdown flag if
  we have JSON support
* src/qemu/qemu_domain.h: Add 'fakeReboot' flag to
  qemuDomainObjPrivate struct
* src/qemu/qemu_driver.c: Fake reboot using the
  system_powerdown command if JSON support is available
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
  src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
  src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
  binding for system_reset command
* src/qemu/qemu_process.c: Reset the guest & start CPUs if
  fakeReboot is set
2011-06-24 12:13:47 +01:00
Osier Yang
d61820df98 qemu: Fix memory leak in qemuProcessWaitForMonitor
Move "VIR_FREE(buf) into label "closelog", so that "buf" could be
freed before returning.
2011-06-23 18:15:25 +08:00
Jiri Denemark
6a15cc6b90 qemu: Only check for NUMA availability if required
We only care about NUMA availability if NUMA configuration is requested
in domain XML.
2011-06-23 09:39:54 +02:00
Dirk Herrendoerfer
cbd8227ee0 set and restore MAC address of a NIC when using PASSTHROUGH mode
The following patch addresses the problem that when a PASSTHROUGH
mode DIRECT NIC connection is made the MAC address of the NIC is
not automatically set and reset to the configured VM MAC and
back again.

The attached patch fixes this problem by setting and resetting the MAC
while remembering the previous setting while the VM is running.
This also works if libvirtd is restarted while the VM is running.

the patch passes make syntax-check
2011-06-21 11:49:40 -04:00
Osier Yang
a6f5c9b600 numatune: Support NUMA memory tuning in qemu driver
Implemented as setting NUMA policy between fork and exec as a hook,
using libnuma. Only support memory tuning on domain process currently.

For the nodemask out of range, will report soft warning instead of
hard error in libvirt layer. (Kernel will be silent as long as one
of set bit in the nodemask is valid on the host. E.g. For a host
has two NUMA nodes, kernel will be silent for nodemask "01010101").
So, soft warning is the only thing libvirt can do, as one might want
to specify the numa policy prior to a node that doesn't exist yet,
however, it may come as hotplug soon.
2011-06-20 15:16:16 +08:00
Jiri Denemark
559fcf8a24 qemu: Implement virDomainGetControlInfo 2011-06-16 18:47:12 +02:00
Adam Litke
12cd77a0c5 Asynchronous event for BlockPull completion
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>
2011-06-14 22:48:42 -06:00
Cole Robinson
c0980a3a6e qemu: Fix parsing 'info chardev'
If qemu supports -chardev, our char frontend aliases are ex. 'charserial0'
not just 'serial0'. Typically we don't use this code path because the
pty's are scraped from stdout.
2011-06-14 10:41:19 -04:00
Cole Robinson
d0b1a9a087 qemu: Scrape stdout for virtio console pty
Currently we forget to do this and have to fallback to info chardev (which
also fails, see following patch)
2011-06-14 10:41:19 -04:00
Taku Izumi
d5f3320de7 vcpupin: Fix cpu affinity setting bug of qemu driver
There is the case where cpu affinites for vcpu of qemu doesn't work
correctly. For example, if only one vcpupin setting entry is provided
and its setting is not for vcpu0, it doesn't work.

   # virsh dumpxml VM
   ...
   <vcpu>4</vcpu>
   <cputune>
     <vcpupin vcpu='3' cpuset='9-11'/>
   </cputune>
   ...

   # virsh start VM
   Domain VM started

   # virsh vcpuinfo VM
   VCPU:           0
   CPU:            31
   State:          running
   CPU time:       2.5s
   CPU Affinity:   yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

   VCPU:           1
   CPU:            12
   State:          running
   CPU time:       0.9s
   CPU Affinity:   yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

   VCPU:           2
   CPU:            30
   State:          running
   CPU time:       1.5s
   CPU Affinity:   yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

   VCPU:           3
   CPU:            13
   State:          running
   CPU time:       1.7s
   CPU Affinity:   yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy

This patch fixes this problem.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
2011-06-14 11:17:54 +08:00
Cole Robinson
1ba75cf9aa qemu: Convert virExec usage to virCommand
v2:
    Have virCommand cleanup intermediate process for us

v3:
    Preserve original FD closing behavior

Signed-off-by: Cole Robinson <crobinso@redhat.com>
2011-06-07 11:11:02 -04:00
Osier Yang
ebf6b11ac1 Use VIR_USE_CPU instead of new wheel 2011-06-07 16:51:51 +08:00
Daniel P. Berrange
a018c0b910 Fix check of virKillProcess return status
The error code for virKillProcess is returned in the errno variable
not the return value. THis mistake caused the logs to be filled with
errors when shutting down QEMU processes

* src/qemu/qemu_process.c: Fix process kill check.
2011-06-04 07:26:07 -04:00
Eric Blake
2834d57175 qemu: avoid memory leak on vcpupin
Detected by Coverity.  This leaked a cpumap on every iteration
of the loop.  Leak introduced in commit 1cc4d02 (v0.9.0).

* src/qemu/qemu_process.c (qemuProcessSetVcpuAffinites): Plug
leak, and hoist allocation outside loop.
2011-06-03 08:11:43 -06:00
Daniel P. Berrange
12317957ec Integrate the QEMU driver with the lock manager infrastructure
The QEMU integrates with the lock manager instructure in a number
of key places

 * During startup, a lock is acquired in between the fork & exec
 * During startup, the libvirtd process acquires a lock before
   setting file labelling
 * During shutdown, the libvirtd process acquires a lock
   before restoring file labelling
 * During hotplug, unplug & media change the libvirtd process
   holds a lock while setting/restoring labels

The main content lock is only ever held by the QEMU child process,
or libvirtd during VM shutdown. The rest of the operations only
require libvirtd to hold the metadata locks, relying on the active
QEMU still holding the content lock.

* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h,
  src/qemu/libvirtd_qemu.aug, src/qemu/test_libvirtd_qemu.aug:
  Add config parameter for configuring lock managers
* src/qemu/qemu_driver.c: Add calls to the lock manager
2011-06-02 10:54:01 +01:00
Daniel P. Berrange
4454a9efc7 Don't kill QEMU process when a monitor I/O parsing error occurs
Currently whenever there is any failure with parsing the monitor,
this is treated in the same was as end-of-file (ie QEMU quit).
The domain is terminated, if not already dead.

With this change, failures in parsing the monitor stream do not
result in the death of QEMU. The guest continues running unchanged,
but all further use of the monitor will be disabled.

The VMM_FAILURE event will be emitted, and the mgmt application
can decide when to kill/restart the guest to re-gain control

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Run a
  different callback for monitor EOF vs error conditions.
* src/qemu/qemu_process.c: Emit VMM_FAILURE event when monitor
  fails
2011-05-29 20:37:29 +08:00
Jiri Denemark
9f1319618a qemu: Update domain state when reconnecting monitor
A qemu domain can get paused when libvirtd is stopped (e.g., because of
I/O error) so we should check its current state when reconnecting to it.
2011-05-16 13:36:08 +02:00
Jiri Denemark
b046c55d40 Implement domain state reason
Only in drivers which use virDomainObj, drivers that query hypervisor
for domain status need to be updated separately in case their hypervisor
supports this functionality.

The reason is also saved into domain state XML so if a domain is not
running (i.e., no state XML exists) the reason will be lost by libvirtd
restart. I think this is an acceptable limitation.
2011-05-16 13:36:08 +02:00
Lai Jiangshan
b65f37a4a1 libvirt,logging: cleanup VIR_XXX0()
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>
2011-05-11 12:41:14 -06:00
Daniel P. Berrange
cbf9f2f2c0 Allow destroying QEMU VM even if a job is active
Introduce a virProcessKill function that can be safely called
even when the job mutex is held. This allows virDomainDestroy
to kill any VM even if it is asleep in a monitor job. The PID
will die and the thread asleep on the monitor will then wake
up releasing the job mutex.

* src/qemu/qemu_driver.c: Kill process before using qemuProcessStop
  to ensure job is released
* src/qemu/qemu_process.c: Add virProcessKill for killing off
  QEMU processes
2011-05-11 09:35:15 +01:00
Daniel P. Berrange
f79cddad55 Make taint warnings also go into the domain logfile
As well as taint warnings going to the main libvirt log,
add taint warnings to the per-domain logfile

  Domain id=3 is tainted: high-privileges
  Domain id=3 is tainted: disk-probing
  Domain id=3 is tainted: shell-scripts
  Domain id=3 is tainted: custom-monitor

* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Enhance
  qemuDomainTaint to also log to the domain logfile
* src/qemu/qemu_driver.c: Pass -1 for logFD to taint methods to
  auto-append to logfile
* src/qemu/qemu_process.c: Pass open logFD at startup for taint
  methods
2011-05-06 12:02:02 +01:00
Daniel P. Berrange
ce1b1f4186 Move qemuProcessLogReadFD and qemuProcessLogFD methods
Move the qemuProcessLogReadFD and qemuProcessLogFD methods
into qemu_domain.c, renaming them to qemuDomainCreateLog
and qemuDomainOpenLog.

* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add
  qemuDomainCreateLog and qemuDomainOpenLog.
* src/qemu/qemu_process.c: Remove qemuProcessLogFD
  and qemuProcessLogReadFD
2011-05-06 12:02:02 +01:00
Daniel P. Berrange
718ac9b52f Log taint warnings in QEMU driver
Wire up logging of VM tainting to the QEMU driver

 - If running QEMU as root user/group or without capabilities
   being cleared
 - If passing custom QEMU command line args
 - If issuing custom QEMU monitor commands
 - If using a network interface config with an associated
   shell script
 - If using a disk config relying on format probing

The warnings, per-VM appear in the main libvirtd logs

  11:56:17.571: 10832: warning : qemuDomainObjTaint:712 : Domain id=1 name='l2' uuid=c7a3edbd-edaf-9455-926a-d65c16db1802 is tainted: high-privileges
  11:56:17.571: 10832: warning : qemuDomainObjTaint:712 : Domain id=1 name='l2' uuid=c7a3edbd-edaf-9455-926a-d65c16db1802 is tainted: disk-probing

The taint flags are reset when the VM is stopped.

* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Helper APIs
  for logging taint warnings
* src/qemu/qemu_driver.c: Log tainting with custom QEMU monitor
  commands and disk/net hotplug with unsupported configs
* src/qemu/qemu_process.c: Log tainting at startup based on
  unsupported configs
2011-05-06 12:02:02 +01:00
Daniel P. Berrange
43c01d3838 Persist qemu capabilities in the domain status file
To cope with the QEMU binary being changed while a VM is running,
it is neccessary to persist the original qemu capabilities at the
time the VM is booted.

* src/qemu/qemu_capabilities.c, src/qemu/qemu_capabilities.h: Add
  an enum for a string rep of every capability
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Support for
  storing capabilities in the domain status XML
* src/qemu/qemu_process.c: Populate & free QEMU capabilities at
  domain startup
2011-05-05 11:33:03 +01:00
Wen Congyang
d2fd997ea6 qemu: fix the check of virDomainObjUnref()'s return value
If vm is unlocked in virDomainObjUnref(), the return value is 0, not less
than 0.
2011-04-19 21:46:09 +08:00
Daniel P. Berrange
ce3ae1b084 build: fix qemu build failure in previous patch
This last minute addition caused a build failure

cc1: warnings being treated as errors
qemu/qemu_process.c: In function 'qemuProcessHandleWatchdog':
qemu/qemu_process.c:436:34: error: ignoring return value of 'virDomainObjUnref', declared with attribute warn_unused_result [-Wunused-result]
make[3]: *** [libvirt_driver_qemu_la-qemu_process.lo] Error 1
2011-04-18 09:27:13 -06:00
Wen Congyang
b060d2e5d4 enhance processWatchdogEvent()
This patch does the following two things:
1. hold an extra reference while handling watchdog event
   If the domain is not persistent, and qemu quits unexpectedly before
   calling processWatchdogEvent(), vm will be freed and the function
   processWatchdogEvent() will be dangerous.

2. unlock qemu driver and vm before returning from processWatchdogEvent()
   When the function processWatchdogEvent() failed, we only free wdEvent,
   but forget to unlock qemu driver and vm, free dumpfile.
2011-04-18 09:38:45 +08:00
Eric Blake
99fa30804b maint: fix grammar errors
Jim Meyering recently improved gnulib to catch various grammar
errors during 'make syntax-check'.

* .gnulib: Update to latest, for syntax-check improvements.
* include/libvirt/libvirt.h.in (virConnectAuthCallbackPtr): Use
cannot rather than two words.
* src/driver.c: Likewise.
* src/driver.h (VIR_SECRET_GET_VALUE_INTERNAL_CALL): Likewise.
* src/remote/remote_driver.c (initialize_gnutls): Likewise.
* src/util/pci.c (pciBindDeviceToStub): Likewise.
* src/storage/storage_backend.c (virStorageBackendCreateQemuImg):
Likewise.
(virStorageBackendUpdateVolTargetInfoFD): Avoid doubled word.
* docs/formatdomain.html.in: Likewise.
* src/qemu/qemu_process.c (qemuProcessStart): Likewise.
* cfg.mk (exclude_file_name_regexp--sc_prohibit_can_not)
(exclude_file_name_regexp--sc_prohibit_doubled_word): Exclude
existing translation problems.
2011-04-12 09:06:14 -06:00
Jiri Denemark
87e78b2bc0 qemu: Support for overriding NPROC limit
This patch adds max_processes option to qemu.conf which can be used to
override system default limit on number of processes that are allowed to
be running for qemu user.
2011-04-06 12:08:59 +02:00
Jiri Denemark
69afdf14b8 qemu: Rewrite LOOKUP_PTYS macro into a function
The macro is huge and gives us nothing but headache when maintaining it.
2011-04-05 14:02:55 +02:00
Matthias Bolte
fb7f0051a2 qemu: Use heap allocated memory to read the monitor greeting
Removing a 4kb stack allocation.

Reduce stack buffer for virStrerror to the common 1kb instead of 4kb.
2011-04-05 08:55:27 +02:00
Eric Blake
0d166c6b7c build: detect potentential uninitialized variables
Even with -Wuninitialized (which is part of autobuild.sh
--enable-compile-warnings=error), gcc does NOT catch this
use of an uninitialized variable:

{
  if (cond)
    goto error;
  int a = 1;
error:
  printf("%d", a);
}

which prints 0 (supposing the stack started life wiped) if
cond was true.  Clang will catch it, but we don't use clang
as often.  Using gcc -Wjump-misses-init catches it, but also
gives false positives:

{
  if (cond)
    goto error;
  int a = 1;
  return a;
error:
  return 0;
}

Here, a was never used in the scope of the error block, so
declaring it after goto is technically fine (and clang agrees).
However, given that our HACKING already documents a preference
to C89 decl-before-statement, the false positive warning is
enough of a prod to comply with HACKING.

[Personally, I'd _really_ rather use C99 decl-after-statement
to minimize scope, but until gcc can efficiently and reliably
catch scoping and uninitialized usage bugs, I'll settle with
the compromise of enforcing a coding standard that happens to
reject false positives if it can also detect real bugs.]

* acinclude.m4 (LIBVIRT_COMPILE_WARNINGS): Add -Wjump-misses-init.
* src/util/util.c (__virExec): Adjust offenders.
* src/conf/domain_conf.c (virDomainTimerDefParseXML): Likewise.
* src/remote/remote_driver.c (doRemoteOpen): Likewise.
* src/phyp/phyp_driver.c (phypGetLparNAME, phypGetLparProfile)
(phypGetVIOSFreeSCSIAdapter, phypVolumeGetKey)
(phypGetStoragePoolDevice)
(phypVolumeGetPhysicalVolumeByStoragePool)
(phypVolumeGetPath): Likewise.
* src/vbox/vbox_tmpl.c (vboxNetworkUndefineDestroy)
(vboxNetworkCreate, vboxNetworkDumpXML)
(vboxNetworkDefineCreateXML): Likewise.
* src/xenapi/xenapi_driver.c (getCapsObject)
(xenapiDomainDumpXML): Likewise.
* src/xenapi/xenapi_utils.c (createVMRecordFromXml): Likewise.
* src/security/security_selinux.c (SELinuxGenNewContext):
Likewise.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeEjectableMedia):
Likewise.
* src/qemu/qemu_process.c (qemuProcessWaitForMonitor): Likewise.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextGetPtyPaths):
Likewise.
* src/qemu/qemu_driver.c (qemudDomainShutdown)
(qemudDomainBlockStats, qemudDomainMemoryPeek): Likewise.
* src/storage/storage_backend_iscsi.c
(virStorageBackendCreateIfaceIQN): Likewise.
* src/node_device/node_device_udev.c (udevProcessPCI): Likewise.
2011-04-04 11:26:29 -06:00
Wen Congyang
4a3976211d fix memory leak in qemuProcessHandleGraphics()
If strdup("x509dname") or strdup("saslUsername") success, but
strdup(x509dname) or strdup(saslUsername) failed, subject->nidentity
is not the num elements of subject->identities, and we will leak some
memory.
2011-04-03 09:13:53 +08:00
Wen Congyang
19f916a764 do not lock vm while allocating memory
There is no need to lock vm while allocating memory. If allocating
memory failed, we forgot to unlock vm.
2011-04-03 09:13:46 +08:00
Jiri Denemark
72ab0b6dc8 qemu: Ignore libvirt debug messages in qemu log
qemu driver uses a 4K buffer for reading qemu log file. This is enough
when only qemu's output is present in the log file. However, when
debugging messages are turned on, intermediate libvirt process fills the
log with a bunch of debugging messages before it executes qemu binary.
In such a case the buffer may become too small. However, we are not
really interested in libvirt messages so they can be filtered out from
the buffer.
2011-04-01 08:48:32 +02:00
Osier Yang
1cc4d0259c cputune: Support cputune for qemu driver
When domain startup, setting cpu affinity and cpu shares according
to the cputune xml specified in domain xml.

Modify "qemudDomainPinVcpu" to update domain config for vcpupin,
and modify "qemuSetSchedulerParameters" to update domain config
for cpu shares.

v1 - v2:
   * Use "VIR_ALLOC_N" instead of "VIR_ALLOC_VAR"
   * But keep raising error when it fails on adding vcpupin xml
     entry, as I still don't have a better idea yet.
2011-03-29 22:13:46 +08:00
Eric Blake
ef701fd8cb docs: document recent hook additions
* src/qemu/qemu_process.c (qemuProcessStart, qemuProcessStop): Fix
typos.
* docs/hooks.html.in: Document 'prepare' and 'release' hooks.
2011-03-28 09:51:04 -06:00
Eric Blake
72d4ff5b7c build: enforce reference count checking
Add the compiler attribute to ensure we don't introduce any more
ref bugs like were just patched in commit 9741f34, then explicitly
mark the remaining places in code that are safe.

* src/qemu/qemu_monitor.h (qemuMonitorUnref): Mark
ATTRIBUTE_RETURN_CHECK.
* src/conf/domain_conf.h (virDomainObjUnref): Likewise.
* src/conf/domain_conf.c (virDomainObjParseXML)
(virDomainLoadStatus): Fix offenders.
* src/openvz/openvz_conf.c (openvzLoadDomains): Likewise.
* src/vmware/vmware_conf.c (vmwareLoadDomains): Likewise.
* src/qemu/qemu_domain.c (qemuDomainObjBeginJob)
(qemuDomainObjBeginJobWithDriver)
(qemuDomainObjExitRemoteWithDriver): Likewise.
* src/qemu/qemu_monitor.c (QEMU_MONITOR_CALLBACK): Likewise.
Suggested by Daniel P. Berrange.
2011-03-24 15:29:18 -06:00
Thibault Vincent
3415eeb53e qemu: add two hook script events "prepare" and "release"
Fix for bug https://bugzilla.redhat.com/show_bug.cgi?id=618970

The "prepare" hook is called very early in the VM statup process
before device labeling, so that it can allocate ressources not
managed by libvirt, such as DRBD, or for instance create missing
bridges and vlan interfaces.
* src/util/hooks.c src/util/hooks.h: add definitions for new hooks
  VIR_HOOK_QEMU_OP_PREPARE and VIR_HOOK_QEMU_OP_RELEASE
* src/qemu/qemu_process.c: use them in qemuProcessStart and
  qemuProcessStop()
2011-03-22 21:12:36 +08:00
Eric Blake
496084175a qemu: respect locking rules
THREADS.txt states that the contents of vm should not be read or
modified while the vm lock is not held, but that the lock must not
be held while performing a monitor command.  This fixes all the
offenders that I could find.

* src/qemu/qemu_process.c (qemuProcessStartCPUs)
(qemuProcessInitPasswords, qemuProcessStart): Don't modify or
refer to vm state outside lock.
* src/qemu/qemu_driver.c (qemudDomainHotplugVcpus): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeGraphicsPasswords):
Likewise.
2011-03-18 13:32:17 -06:00
Jiri Denemark
3b8bf4a3a9 qemu: Fix warnings in event handlers
Some qemu monitor event handlers were issuing inadequate warning when
virDomainSaveStatus() failed. They copied the message from I/O error
handler without customizing it to provide better information on why
virDomainSaveStatus() was called.
2011-03-10 14:18:37 +01:00
Eric Blake
48096a0064 audit: rename remaining qemu audit functions
Also add ATTRIBUTE_NONNULL markers.

* src/qemu/qemu_audit.h: The pattern qemuDomainXXXAudit is
inconsistent; prefer qemuAuditXXX instead.
* src/qemu/qemu_audit.c: Reflect the renames.
* src/qemu/qemu_driver.c: Likewise.
* src/qemu/qemu_hotplug.c: Likewise.
* src/qemu/qemu_migration.c: Likewise.
* src/qemu/qemu_process.c: Likewise.
2011-03-09 11:35:20 -07:00
Laine Stump
f8ac67909d qemu: avoid corruption of domain hashtable and misuse of freed domains
This was also found while investigating

   https://bugzilla.redhat.com/show_bug.cgi?id=670848

An EOF on a domain's monitor socket results in an event being queued
to handle the EOF. The handler calls qemuProcessHandleMonitorEOF. If
it is a transient domain, this leads to a call to
virDomainRemoveInactive, which removes the domain from the driver's
hashtable and unref's it. Nowhere in this code is the qemu driver lock
acquired.

However, all modifications to the driver's domain hashtable *must* be
done while holding the driver lock, otherwise the hashtable can become
corrupt, and (even more likely) another thread could call a different
hashtable function and acquire a pointer to the domain that is in the
process of being destroyed.

To prevent such a disaster, qemuProcessHandleMonitorEOF must get the
qemu driver lock *before* it gets the DomainObj's lock, and hold it
until it is finished with the DomainObj. This guarantees that nobody
else modifies the hashtable at the same time, and that anyone who had
already gotten the DomainObj from the hashtable prior to this call has
finished with it before we remove/destroy it.
2011-03-04 08:13:11 -05:00
Laine Stump
e570ca1246 qemu: Add missing lock of virDomainObj before calling virDomainUnref
This was found while researching the root cause of:

https://bugzilla.redhat.com/show_bug.cgi?id=670848

virDomainUnref should only be called with the lock held for the
virDomainObj in question. However, when a transient qemu domain gets
EOF on its monitor socket, it queues an event which frees the monitor,
which unref's the virDomainObj without first locking it. If another
thread has already locked the virDomainObj, the modification of the
refcount could potentially be corrupted. In an extreme case, it could
also be potentially unlocked by virDomainObjFree, thus left open to
modification by anyone else who would have otherwise waited for the
lock (not to mention the fact that they would be accessing freed
data!).

The solution is to have qemuMonitorFree lock the domain object right
before unrefing it. Since the caller to qemuMonitorFree doesn't expect
this lock to be held, if the refcount doesn't go all the way to 0,
qemuMonitorFree must unlock it after the unref.
2011-03-04 08:12:58 -05:00