When domain XML contains any of the elements for setting up CPU
scheduling parameters (period, quota, emulator_period, or
emulator_quota) we need cpu cgroup to enforce the configuration.
However, the existing code would just ignore silently such settings if
either cgroups were not available at all cpu cgroup was not available.
Moreover, APIs for manipulating CPU scheduler parameters were already
failing if cpu cgroup was not available. This patch makes cpu cgroup
mandatory for all domains that use CPU scheduling elements in their XML.

The variable max_id is initialized again in the step of
getting cpu mapping variable map2. But in the next for loop
we still expect original value of max_id, the bug will
crash libvirtd when using on NUMA machine with big number
of cpus.

virDomainVcpuPinAdd does a realloc on vcpupin_list if the new vcpu pin
definition doesn't fit into the array. The list is an array of pointers
but the function definition didn't support returning the changed pointer
to the caller if it was realloced. This caused segfaults if realloc
would change the base pointer.

Commit d0c0e79a left behind some dead
code (hasDAC can't be efectively set to true, because
virSecurityManagerNew fails to load the "dac" driver).

This patch also enhances the condition for adding the default
auto-detected security manager if the manager array is allocated but
empty.

Also the configuration file for qemu driver still contains reference to
the DAC driver that can't be enabled manualy.

Before commit 05447e3a, qemuAgentCommand
blocked until it got a reply or appropriate event. When new parameter
was added to qemuAgentCommand in the above commit, all existing callers
of it were updated in a wrong way changing them from blocking to
5-seconds timeout.

The @timeout parameter of qemuAgentSend is both redundant and confusing.
This patch should not result in any functional changes.

This bug was revealed by the crash described in

  https://bugzilla.redhat.com/show_bug.cgi?id=852383

The vlan info pointer sent to virNetDevOpenvswitchAddPort should never
be non-NULL unless there is at least one tag. The factthat such a vlan
info pointer was receveid pointed out that a caller was passing the
wrong pointer. Instead of sending &net->vlan, the result of
virDomainNetGetActualVlan(net) should be sent - that function will
look for vlan info in net->data.network.actual->vlan, and in cany case
return NULL instead of a pointer if the vlan info it finds has no
tags.

Aside from causing the crash, sending a hardcoded &net->vlan has the
effect of ignoring vlan info from a <network> or <portgroup> config.

As the next boot doesn't have to worry about the previous numa
params setting (there is no).

If no 'security_driver' config option was set, then the code
just loaded the 'dac' security driver. This is a regression
on previous behaviour, where we would probe for a possible
security driver. ie default to SELinux if available.

This changes things so that it 'security_driver' is not set,
we once again do probing. For simplicity we also always
create the stack driver, even if there is only one driver
active.

The desired semantics are:

 - security_driver not set
     -> probe for selinux/apparmour/nop
     -> auto-add DAC driver
 - security_driver set to a string
     -> add that one driver
     -> auto-add DAC driver
 - security_driver set to a list
     -> add all drivers in list
     -> auto-add DAC driver

It is not allowed, or possible to specify 'dac' in the
security_driver config param, since that is always
enabled.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The security driver loading code in qemu has a flaw that causes it to
register the DAC security driver twice. This causes problems (machines
unable to start) as the two DAC drivers clash together.

This patch refactors the code to allow loading the DAC driver even if
its specified in configuration (it can't be registered as a common
security driver), and does not add the driver twice.

If cgroups are enabled in general but cpu cgroup is disabled in
qemu.conf or not mounted at all, libvirt would refuse to start any
domain even though scheduler parameters are not set in domain XML.

This patch makes cpu cgroup mandatory only for domains that actually
want to use it.

To keep the internal data structure consistent.

With current flow in qemudDomainDefine we might lose data
when updating an existing domain. We parse given XML and
overwrite the configuration.  Then we try to save the new
config. However, this step may fail and we don't perform any
roll back.  In fact, we remove the domain from the list of
domains held up by qemu driver. This is okay as long as the
domain was brand new one.

Currently, if a syscall in qemu_agent.c fails we report an internal
error even though we should be reporting a system error.

Currently, when guest agent is configured but not responsive
(e.g. due to appropriate service not running in the guest)
we return VIR_ERR_INTERNAL_ERROR. Both are wrong. Therefore
we need to introduce new error code to reflect this case.

With the latest patches libvirt supports qemu agent monitor
passthrough. However, function in qemu driver is called
qemuDrvDomainAgentCommand. s/Drv// as used in all other names.

In my quest for reusing variables I failed to edit one variable when
fixing details between two patch versions. That results in a failure
to start qemu with autoport and spice tls, because qemu is trying to
bind two sockets to the same port.

Commit 4b03d591 changed the pinning
behavior in a way that makes some machines non-startable.

The comment mentioning that we cannot control each vcpu when there is
not VCPU<-> PID mapping available is true, however, this isn't
necessarily an error, because this can be caused by old QEMU without
support for "query-cpus" command as well as a software emulated
machines that don't create more than one process.

The name 'virDomainDiskSnapshot' didn't fit in with our normal
conventions of using a prefix hinting that it is related to a
virDomainSnapshotPtr.  Also, a future patch will reuse the
enum for declaring where the VM memory is stored.

* src/conf/snapshot_conf.h (virDomainDiskSnapshot): Rename...
(virDomainSnapshotLocation): ...to this.
(_virDomainSnapshotDiskDef): Update clients.
* src/conf/domain_conf.h (_virDomainDiskDef): Likewise.
* src/libvirt_private.syms (domain_conf.h): Likewise.
* src/conf/domain_conf.c (virDomainDiskDefParseXML)
(virDomainDiskDefFormat): Likewise.
* src/conf/snapshot_conf.c: (virDomainSnapshotDiskDefParseXML)
(virDomainSnapshotAlignDisks, virDomainSnapshotDefFormat):
Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDiskPrepare)
(qemuDomainSnapshotCreateSingleDiskActive)
(qemuDomainSnapshotCreateDiskActive, qemuDomainSnapshotCreateXML):
Likewise.

This has several benefits:
1. Future snapshot-related code has a definite place to go (and I
_will_ be adding some)
2. Snapshot errors now use the VIR_FROM_DOMAIN_SNAPSHOT error
classification, which has been underutilized (previously only in
libvirt.c)

* src/conf/domain_conf.h, domain_conf.c: Split...
* src/conf/snapshot_conf.h, snapshot_conf.c: ...into new files.
* src/Makefile.am (DOMAIN_CONF_SOURCES): Build new files.
* po/POTFILES.in: Mark new file for translation.
* src/vbox/vbox_tmpl.c: Update caller.
* src/esx/esx_driver.c: Likewise.
* src/qemu/qemu_command.c: Likewise.
* src/qemu/qemu_domain.h: Likewise.

We were failing to react to allocation failure when initializing
a snapshot object list.  Changing things to store a pointer
instead of a complete object adds one more possible point of
allocation failure, but at the same time, will make it easier to
react to failure now, as well as making it easier for a future
patch to split all virDomainSnapshotPtr handling into a separate
file, as I continue to add even more snapshot code.

Luckily, there was only one client outside of domain_conf.c that
was actually peeking inside the object, and a new wrapper function
was easy.

* src/conf/domain_conf.h (_virDomainObj): Use a pointer.
(virDomainSnapshotObjListInit): Rename.
(virDomainSnapshotObjListFree, virDomainSnapshotForEach): New
declarations.
(_virDomainSnapshotObjList): Move definitions...
* src/conf/domain_conf.c: ...here.
(virDomainSnapshotObjListInit, virDomainSnapshotObjListDeinit):
Rename...
(virDomainSnapshotObjListNew, virDomainSnapshotObjListFree): ...to
these.
(virDomainSnapshotForEach): New function.
(virDomainObjDispose, virDomainListPopulate): Adjust callers.
* src/qemu/qemu_domain.c (qemuDomainSnapshotDiscard)
(qemuDomainSnapshotDiscardAllMetadata): Likewise.
* src/qemu/qemu_migration.c (qemuMigrationIsAllowed): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotLoad)
(qemuDomainUndefineFlags, qemuDomainSnapshotCreateXML)
(qemuDomainSnapshotListNames, qemuDomainSnapshotNum)
(qemuDomainListAllSnapshots)
(qemuDomainSnapshotListChildrenNames)
(qemuDomainSnapshotNumChildren)
(qemuDomainSnapshotListAllChildren)
(qemuDomainSnapshotLookupByName, qemuDomainSnapshotGetParent)
(qemuDomainSnapshotGetXMLDesc, qemuDomainSnapshotIsCurrent)
(qemuDomainSnapshotHasMetadata, qemuDomainRevertToSnapshot)
(qemuDomainSnapshotDelete): Likewise.
* src/libvirt_private.syms (domain_conf.h): Export new function.

The recent virDomainQemuAgentCommand addition is part of 0.10.0;
also, grouping all libvirt-qemu.so callbacks together makes them
easier to identify.

* src/libvirt_qemu.syms: Fix release symbol.
* src/qemu/qemu_driver.c (qemuDriver): Likewise.
* src/remote/remote_driver.c (remote_driver): Likewise.
* src/driver.h (_virDriver): Group qemu-specific callbacks.

If a domain is pmsuspended then virsh suspend will succeed. Beside
obvious flaw, virsh resume will report success and change domain
state to running which is another mistake. Therefore we must forbid
any attempts for suspend and resume when pmsuspended.

Add qemuDrvDomainAgentCommand() for .qemuDomainArbitraryAgentCommand
to qemu driver.
Signed-off-by: NMATSUDA Daiki <matsudadik@intellilink.co.jp>

Add a function qemuAgentArbitraryCommand() for general qemu agent command.
Signed-off-by: NMATSUDA Daiki <matsudadik@intellilink.co.jp>

Add @seconds variable to qemuAgentSend().
When @timemout is true, @seconds controls how long to wait for a
response (if @seconds is VIR_DOMAIN_QEMU_AGENT_COMMAND_DEFAULT,
default to QEMU_AGENT_WAIT_TIME).
In addition, @seconds must be >= 0 or VIR_DOMAIN_QEMU_AGENT_COMMAND_DEFAULT.
If @timeout is false, @seconds is ignored.
Signed-off-by: NMATSUDA Daiki <matsudadik@intellilink.co.jp>

allow the user change/get emulator's period and quota when the vm is running.

This patch introduces support of setting emulator's period and
quota to limit cpu bandwidth when the vm starts.  Also updates
XML Schema for new entries and docs.

This patch changes the behaviour of xml element cputune.period
and cputune.quota to limit cpu bandwidth only for vcpus, and no
longer limit cpu bandwidth for the whole guest.

The reasons to do this are:

  - This matches docs of cputune.period and cputune.quota.
  - The other parts excepting vcpus are treated as "emulator",
    and there are separate period/quota settings for emulator
    in the subsequent patches

Introduce 2 APIs to support emulator threads pin in qemu driver.

    1) qemudDomainPinEmulator: setup emulator threads pin info.
    2) qemudDomainGetEmulatorPinInfo: get all emulator threads pin info.

They are similar to qemudDomainPinVcpuFlags and qemudDomainGetVcpuPinInfo.
And also, remoteDispatchDomainPinEmulatorFlags and remoteDispatchDomainGetEmulatorPinInfo
functions are introduced.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>

Emulator threads should also be pinned by sched_setaffinity(), just
the same as vcpu threads.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>

Introduce qemuSetupCgroupEmulatorPin() function to add emulator
threads pin info to cpuset cgroup, the same as vcpupin.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>

vcpu threads pin are implemented using sched_setaffinity(), but
not controlled by cgroup. This patch does the following things:

    1) enable cpuset cgroup
    2) reflect all the vcpu threads pin info to cgroup
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>

Create a new cgroup and move all emulator threads to the new cgroup.
And then we can do the other things:
1. limit only vcpu usage rather than the whole qemu
2. limit for emulator threads(include vhost-net threads)
Signed-off-by: NWen Congyang <wency@cn.fujitsu.com>
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>

Qemu command line generation for geometry override and testcases.
Signed-off-by: NJ.B. Joret <jb@linux.vnet.ibm.com>
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

After the cleanup of remote display port allocation, I noticed some
messages that didn't make a lot of sense the way they were written. So
I rephrased them.

The defines QEMU_REMOTE_PORT_MIN and QEMU_REMOTE_PORT_MAX were used to
find free port when starting domains. As this was hard-coded to the
same ports as default VNC servers, there were races with these other
programs. This patch includes the possibility to change the default
starting port as well as the maximum port (mostly for completeness) in
qemu config file.

Support for two new config options in qemu.conf is added:
 - remote_port_min (defaults to QEMU_REMOTE_PORT_MIN and
   must be >= than this value)
 - remote_port_max (defaults to QEMU_REMOTE_PORT_MAX and
   must be <= than this value)

Port allocations for SPICE and VNC behave almost the same (with
default ports), but there is some mess in the code. This patch clears
these inconsistencies and makes sure the same behavior will be used
when ports for remote displays are changed.

Changes:
 - hard-coded number 5900 removed (handled elsewhere like with VNC)
 - reservedVNCPorts renamed to reservedRemotePorts (it's not just for
   VNC anymore)
 - QEMU_VNC_PORT_{MIN,MAX} renamed to QEMU_REMOTE_PORT_{MIN,MAX}
 - port allocation unified for VNC and SPICE