QEMU supports setting vendor and product strings for disk since
1.2.0 (only scsi-disk, scsi-hd, scsi-cd support it), this patch
exposes it with new XML elements <vendor> and <product> of disk
device.

Unmanaged PCI devices were only leaked if pciDeviceListAdd failed but
managed devices were always leaked. And leaking PCI device is likely to
leave PCI config file descriptor open. This patch fixes
qemuReattachPciDevice to either free the PCI device or add it to the
inactivePciHostdevs list.

The device is still referenced from pcidevs and freeing it would leave
an invalid pointer there.

An attempt to attach device that is already attached to a domain results
in the following error:

virsh # attach-device rhel6 pci2 --persistent
error: Failed to attach device from pci2
error: invalid argument: device is already in the domain configuration

The "invalid argument" error code looks wrong, we usually use "operation
invalid" when the action cannot be done in current state.

"disk" is initialized to "dev->data.disk" in the beginning of the
function.

Only one error in qemu_monitor was already using the relatively
new OPERATION_UNSUPPORTED error, even though it is a better fit
for all of the messages related to options that are unsupported
due to the version of qemu in use rather than due to a user's
XML or .conf file choice.  Suggested by Osier Yang.

* src/qemu/qemu_monitor.c (qemuMonitorSendFileHandle)
(qemuMonitorAddHostNetwork, qemuMonitorRemoveHostNetwork)
(qemuMonitorAttachDrive, qemuMonitorDiskSnapshot)
(qemuMonitorDriveMirror, qemuMonitorTransaction)
(qemuMonitorBlockCommit, qemuMonitorDrivePivot)
(qemuMonitorBlockJob, qemuMonitorSystemWakeup)
(qemuMonitorGetVersion, qemuMonitorGetMachines)
(qemuMonitorGetCPUDefinitions, qemuMonitorGetCommands)
(qemuMonitorGetEvents, qemuMonitorGetKVMState)
(qemuMonitorGetObjectTypes, qemuMonitorGetObjectProps)
(qemuMonitorGetTargetArch): Use better error category.

Without this patch, attempts to create a disk snapshot when qemu
is too old results in a cryptic message:

virsh # snapshot-create 23 --disk-only
error: operation failed: Failed to take snapshot: unknown command: 'snapshot_blkdev'

Now it reports:

virsh # snapshot-create 23 --disk-only
error: unsupported configuration: live disk snapshot not supported with this QEMU binary

All versions of qemu that support live disk snapshot also support
QMP (basically upstream qemu 1.1 and later, and backports to RHEL 6.2).

* src/qemu/qemu_capabilities.h (QEMU_CAPS_DISK_SNAPSHOT): New
capability.
* src/qemu/qemu_capabilities.c (qemuCaps): Track it.
(qemuCapsProbeQMPCommands): Set it.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateDiskActive): Use
it.
* src/qemu/qemu_monitor.c (qemuMonitorDiskSnapshot): Simplify.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDiskSnapshot):
Likewise.
* src/qemu/qemu_monitor_text.h (qemuMonitorTextDiskSnapshot):
Delete.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextDiskSnapshot):
Likewise.

Currently to deal with auto-shutdown libvirtd must periodically
poll all stateful drivers. Thus sucks because it requires
acquiring both the driver lock and locks on every single virtual
machine. Instead pass in a "inhibit" callback to virStateInitialize
which drivers can invoke whenever they want to inhibit shutdown
due to existance of active VMs.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When the virStateStop() method is invoked, perform a managed
save of all VMs currently running
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Since we can't (currently) rely on the ability to provide blanket
support for all possible network changes by calling the toplevel
netdev hostside disconnect/connect functions (due to qemu only
supporting a lockstep between initialization of host side and guest
side of devices), in order to support live change of an interface's
nwfilter we need to make a special purpose function to only call the
nwfilter teardown and setup functions if the filter for an interface
(or its parameters) changes. The pattern is nearly identical to that
used to change the bridge that an interface is connected to.

This patch was inspired by a request from Guido Winkelmann
<guido@sagersystems.de>, who tested an earlier version.

The fact that only the guest agent, or ACPI flag can be used
when requesting reboot/shutdown is merely a limitation of the
QEMU driver impl at this time. Thus it should not be in
libvirt.c code
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The default machine type must be stored in the first element of
the caps->machineTypes array. This was done for help output
parsing but not for QMP probing.

Added a helper function qemuSetDefaultMachine to apply the same
fix up for both probing methods.

Further, it was necessary to set caps->nmachineTypes after QMP
probing.
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

detecet by

	http://honk.sigxcpu.org:8001/job/libvirt-build/348/console

https://bugzilla.redhat.com/show_bug.cgi?id=872292

Libvirt should not attempt to call a QMP command that has not been
documented in qemu.git - if future qemu introduces a command by the
same name but with subtly different semantics, then libvirt will be
broken when trying to use that command.

We also had some code that could never be reached - some of our
commands have an alternate for new vs. old qemu HMP commands; but
if we are new enough to support QMP, we only need a fallback to
the new HMP counterpart, and don't need to try for a QMP counterpart
for the old HMP version.

See also this attempt to convert the three snapshot commands to QMP:
https://lists.gnu.org/archive/html/qemu-devel/2012-07/msg01597.html
although it looks like that will still not happen before qemu 1.3.
That thread eventually decided that qemu would use the name
'save-vm' rather than 'savevm', which mitigates the fact that
libvirt's attempt to use a QMP 'savevm' would be broken, but we
might not be as lucky on the other commands.

* src/qemu/qemu_monitor_json.c (qemuMonitorJSONSetCPU)
(qemuMonitorJSONAddDrive, qemuMonitorJSONDriveDel)
(qemuMonitorJSONCreateSnapshot, qemuMonitorJSONLoadSnapshot)
(qemuMonitorJSONDeleteSnapshot): Use only HMP fallback for now.
(qemuMonitorJSONAddHostNetwork, qemuMonitorJSONRemoveHostNetwork)
(qemuMonitorJSONAttachDrive, qemuMonitorJSONGetGuestDriveAddress):
Delete; QMP implies QEMU_CAPS_DEVICE, which prefers AddNetdev,
RemoveNetdev, and AddDrive anyways (qemu_hotplug.c has all callers).
* src/qemu/qemu_monitor.c (qemuMonitorAddHostNetwork)
(qemuMonitorRemoveHostNetwork, qemuMonitorAttachDrive): Reflect
deleted commands.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONAddHostNetwork)
(qemuMonitorJSONRemoveHostNetwork, qemuMonitorJSONAttachDrive):
Likewise.

https://bugzilla.redhat.com/show_bug.cgi?id=876828

Commit 38c4a9cc introduced a regression in hot unplugging of disks
from qemu, where cgroup device ACLs were no longer being revoked
(thankfully not a security hole: cgroup ACLs only prevent open()
of the disk; so reverting the ACL prevents future abuse but doesn't
stop abuse from an fd that was already opened before the ACL change).

Commit 1b2ebf95 overlooked that there were two spots affected.

* src/qemu/qemu_hotplug.c (qemuDomainDetachDiskDevice):
Transfer backing chain before deletion.
* src/qemu/qemu_driver.c (qemuDomainDetachDeviceDiskLive): Fix
spacing (partly to ensure a different-looking patch).

This patch adds two labels and gets rid of a ton of duplicated code.
This patch also fixes some error message and switches most of them to
proper error reporting functions.

This patch adds macros to help retrieve configuration values from qemu
driver's configuration. Some configuration options are grouped
together in the process.

The virStateInitialize method and several cgroups methods were
using an 'int privileged' parameter or similar for dual-state
values. These are better represented with the bool type.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

As of 1a50ba2c we fail to connect to the
monitor instead of getting an exit status != 0 from qemu itself.  This
breaks capabilities probing for the non QMP case.

Replace the following names

 * struct qemu_snap_remove  with virQEMUSnapRemovePtr
 * struct qemu_snap_reparent with virQEMUSnapReparentPtr
 * struct qemu_save_header with virQEMUSaveHeaderPtr
 * enum qemu_save_formats with virQEMUSaveFormat
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Remove the obsolete 'qemud' naming prefix and underscore
based type name. Introduce virQEMUDriverPtr as the replacement,
in common with LXC driver naming style

Throughout the code, we've always used VIR_DOMAIN_SHUTDOWN* flags
even for virDomainReboot() API and its implementation. Fortunately,
the appropriate macros has the same value. But if we want to keep
things consistent, we should be using the correct macros. This
patch doesn't break anything, luckily.

This reverts 8927c0ea qemu: fix a crash when save file can't be opened
and allows virFileWrapperFdCatchError to be called with NULL instead.

Error messages produced while dispatching guest agent commands didn't
have an apparent reference to the fact that they are dealing with guest
agent commands. This patch fixes up some of the messages to contain that
reference.

using qemu guest agent. As said in previous patch,
@mountPoint must be NULL and @flags zero because
qemu guest agent doesn't support these arguments
yet. If qemu learns them, we can start supporting
them as well.

With QMP capability probing, the version was not set.
virsh version returns:
...
Cannot extract running QEMU hypervisor version

This is fixed by computing caps->version from QMP major,
minor, micro values.
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

QMP Capability probing will fail if QEMU cannot bind to the
QMP monitor socket in the qemu_driver->libDir directory.
That's because the child process is stripped of all
capabilities and this directory is chown'ed to the configured
QEMU user/group (normally qemu:qemu) by the QEMU driver.

To prevent this from happening, the driver startup will now pass
the QEMU uid and gid down to the capability probing code.
All capability probing invocations of QEMU will be run with
the configured QEMU uid instead of libvirtd's.

Furter, the pid file handling is moved to libvirt, as QEMU
cannot write to the qemu_driver->runDir (root:root). This also
means that the libvirt daemonizing must be used.
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

If qemuMonitorOpenUnix is called without a related pid, i.e. for
QMP probing, a connect failure can happen as the result of a race.
Without a pid there is no retry and thus we give up too early.
This changes the code to retry if no pid is supplied.
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

In qemuDomainSaveMemory, wrapperFd might be NULL and should be checked before
calling virFileWrapperFdCatchError. Same in doCoreDump.

Bug: https://bugzilla.redhat.com/show_bug.cgi?id=880919

Change some legacy function names to use 'qemu' as their
prefix instead of 'qemud' which was a hang over from when
the QEMU driver ran inside a separate daemon
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=876828

Commit 38c4a9cc introduced a regression in hot unplugging of disks
from qemu, where cgroup device ACLs were no longer being revoked
(thankfully not a security hole: cgroup ACLs only prevent open()
of the disk; so reverting the ACL prevents future abuse but doesn't
stop abuse from an fd that was already opened before the ACL change).

The actual regression is due to a latent bug.  The hot unplug code
was computing the set of files needing cgroup ACL revocation based
on the XML passed in by the user, rather than based on the domain's
details on which disk was being deleted.  As long as the revoke
path was always recomputing the backing chain, this didn't really
matter; but now that we want to compute the chain exactly once and
remember that computation, we need to hang on to the backing chain
until after the revoke has happened.

* src/qemu/qemu_hotplug.c (qemuDomainDetachPciDiskDevice):
Transfer backing chain before deletion.

Qemu accepts gluster protocol as supported storage backend beside others.
Signed-off-by: NHarsh Prateek Bora <harsh@linux.vnet.ibm.com>

This patch introduces the RNG schema and updates necessary data strucutures
to allow various hypervisors to make use of Gluster protocol as one of the
supported network disk backend. Next patch will add support to make use of
this feature in Qemu since it now supports Gluster protocol as one of the
network based storage backend.

Two new optional attributes for <host> element are introduced - 'transport'
and 'socket'. Valid transport values are tcp, unix or rdma. If none specified,
tcp is assumed. If transport is unix, socket specifies path to unix socket.

This patch allows users to specify disks on gluster backends like this:

    <disk type='network' device='disk'>
      <driver name='qemu' type='raw'/>
      <source protocol='gluster' name='Volume1/image'>
        <host name='example.org' port='6000' transport='tcp'/>
      </source>
      <target dev='vda' bus='virtio'/>
    </disk>

    <disk type='network' device='disk'>
      <driver name='qemu' type='raw'/>
      <source protocol='gluster' name='Volume2/image'>
        <host transport='unix' socket='/path/to/sock'/>
      </source>
      <target dev='vdb' bus='virtio'/>
    </disk>
Signed-off-by: NHarsh Prateek Bora <harsh@linux.vnet.ibm.com>

Although we require various C99 features, we don't yet require a
complete C99 compiler.  On RHEL 5, compilation complained:

qemu/qemu_command.c: In function 'qemuBuildGraphicsCommandLine':
qemu/qemu_command.c:4688: error: 'for' loop initial declaration used outside C99 mode

* src/qemu/qemu_command.c (qemuBuildGraphicsCommandLine): Declare
variable sooner.
* src/qemu/qemu_process.c (qemuProcessInitPasswords): Likewise.

The error "... but the cause is unknown" appeared for XMLs similar to
this:

 <disk type='file' device='cdrom'>
   <driver name='qemu' type='raw'/>
   <source file='/dev/zero'/>
   <target dev='sr0'/>
 </disk>

Notice unsupported disk type (for the driver), but also no address
specified. The first part is not a problem and we should not abort
immediately because of that, but the combination with the address
unknown was causing an unspecified error.

While fixing this, I added an error to one place where this return
value was not managed properly.

I have been testing libvirt v1.0.0 for deployment within my
organization, and in the process discovered what appears to be a bug
that breaks virsh attach-device, when attaching an RBD volume to an
instance. First, here is the error presented, with v1.0.0 (this worked
in v0.10.2):

[root@host ~]# virsh attach-device W5APQ8  G84VV1.xml
error: Failed to attach device from G84VV1.xml
error: cannot open file 'dc3-1-test/G84VV1': No such file or directory

Using git bisect, I narrowed the problem down to this as the first
commit to break this setup:

4d34c929 is the first bad commit