Implement the qemu driver's virDomainQemuMonitorCommand
and hook it into the API entry point.

Changes since v1:
 - Rename the (external) qemuMonitorCommand to qemuDomainMonitorCommand
 - Add virCheckFlags to qemuDomainMonitorCommand

Changes since v2:
 - Drop ATTRIBUTE_UNUSED from the flags

Changes since v3:
 - Add a flag to priv so we only print out monitor command warning once.  Note
   that this has not been plumbed into qemuDomainObjPrivateXMLFormat or
   qemuDomainObjPrivateXMLParse, which means that if you run a monitor command,
   restart libvirtd, and then run another monitor command, you may get an
   an erroneous VIR_INFO.  It's a pretty minor matter, and I didn't think it
   warranted the additional code.
 - Add BeginJob/EndJob calls around EnterMonitor/ExitMonitor
Signed-off-by: NChris Lalancette <clalance@redhat.com>

The patches for shared storage migration were not correctly written
for json mode. Thus the 'blk' and 'inc' parameters were never being
set. In addition they didn't set the QEMU_MONITOR_MIGRATE_BACKGROUND
so migration was synchronous. Due to multiple bugs in QEMU's JSON
impl this wasn't noticed because it treated the sync migration requst
as asynchronous anyway. Finally 'background' parameter was converted
to take arbitrary flags but not renamed, and not all uses were changed
to unsigned int.

* src/qemu/qemu_driver.c: Set QEMU_MONITOR_MIGRATE_BACKGROUND in
  doNativeMigrate
* src/qemu/qemu_monitor_json.c: Process QEMU_MONITOR_MIGRATE_NON_SHARED_DISK
  and QEMU_MONITOR_MIGRATE_NON_SHARED_INC flags
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
  src/qemu/qemu_monitor_json.h, src/qemu/qemu_monitor_text.c,
  src/qemu/qemu_monitor_text.h: change 'int background' to
  'unsigned int flags' in migration APIs. Add logging of flags
  parameter

The virDomainGetBlockInfo API allows query physical block
extent and allocated block extent. These are normally the
same value unless storing a special format like qcow2
inside a block device. In this scenario we can query QEMU
to get the actual allocated extent.

Since last time:

 - Return fatal error in text monitor
 - Only invoke monitor command for block devices
 - Fix error handling JSON code

* src/qemu/qemu_driver.c: Fill in block aloction extent when VM
  is running
* 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
  API to query the highest block extent via info blockstats

QEMU is gaining a new monitor command netdev_add for hotplugging
NICs using the netdev backend code. We already support this on
the command this, though it is disabled. This adds support for
hotplug too, also to remain disabled until 0.13 QEMU is released

* src/qemu/qemu_driver.c: Support netdev hotplug for NICs
* 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
  support for netdev_add and netdev_remove commands

The save process was relying on use of the shell >> append
operator to ensure the save data was placed after the libvirt
header + XML. This doesn't work for block devices though.
Replace this code with use of 'dd' and its 'seek' parameter.
This means that we need to pad the header + XML out to a
multiple of dd block size (in this case we choose 512).

The qemuMonitorMigateToCommand() monitor API is used for both
save/coredump, and migration via UNIX socket. We can't simply
switch this to use 'dd' since this causes problems with the
migration usage. Thus, create a dedicated qemuMonitorMigateToFile
which can accept an filename + offset, and remove the filename
from the current qemuMonitorMigateToCommand() API

* src/qemu/qemu_driver.c: Switch to qemuMonitorMigateToFile
  for save and core dump
* 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: Create
  a new qemuMonitorMigateToFile, separate from the existing
  qemuMonitorMigateToCommand to allow handling file offsets

The parameter for the qemuMonitorDeviceDel() is a device alias,
not a device config string. Rename the parameter reflect this
and avoid confusion to readers.

* 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:
  Rename devicestr to devalias in qemuMonitorDeviceDel()

The QEMU driver is mistakenly calling directly into the text
mode monitor for the domain memory stats query.

* src/qemu/qemu_driver.c: Replace qemuMonitorTextGetMemoryStats with
  qemuMonitorGetMemoryStats
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add the new
  wrapper for qemuMonitorGetMemoryStats
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h: Add
  qemuMonitorJSONGetMemoryStats implementation

Signed-off-by: NChris Lalancette <clalance@redhat.com>

* global: patch created by running:
for f in $(git ls-files '*.[ch]') ; do
    cppi $f > $f.t && mv $f.t $f
done

QEMU has a monitor command 'set_cpu' which allows a specific
CPU to be toggled between online& offline state. libvirt CPU
hotplug does not work in terms of individual indexes CPUs.
Thus to support this, we iteratively toggle the online state
when the total number of vCPUs is adjusted via libvirt

NB, currently untested since QEMU segvs when running this!

* src/qemu/qemu_driver.c: Toggle online state for CPUs when
  doing hotplug
* 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
  monitor API for toggling a CPU's online status via 'set_cpu

when the underlying qemu supports the drive/device model and the
controller has been added this way.
* src/qemu/qemu_driver.c: use qemuMonitorDelDevice() when detaching
  PCI controller and if supported
* src/qemu/qemu_monitor.[ch]: add new qemuMonitorDelDevice() function
* src/qemu/qemu_monitor_json.[ch]: JSON backend for DelDevice command
* src/qemu/qemu_monitor_text.[ch]: Text backend for DelDevice command

When in JSON mode, QEMU requires that 'qmp_capabilities' is run as
the first command in the monitor. This is a no-op when run in the
text mode monitor

* src/qemu/qemu_driver.c: Run capabilities negotiation when
  connecting to the monitor
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
  src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h: Add
  support for the 'qmp_capabilities' command, no-op in text mode.

The old text mode monitor prompts for a password when disks are
encrypted. This interactive approach doesn't work for JSON mode
monitor. Thus there is a new 'block_passwd' command that can be
used.

* src/qemu/qemu_driver.c: Split out code for looking up a disk
  secret from findVolumeQcowPassphrase, into a new method
  getVolumeQcowPassphrase. Enhance qemuInitPasswords() to also
  set the disk encryption password via the monitor
* 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
  support for the 'block_passwd' monitor command.

The way QEMU is started has been changed to use '-device' and
the new style '-drive' syntax. This needs to be mirrored in
the hotplug code, requiring addition of two new APIs.

* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Define APIs
  qemuMonitorAddDevice() and qemuMonitorAddDrive()
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
  src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
  Implement the new monitor APIs

* src/util/json.c, src/util/json.h: Declare returned strings
  to be const
* src/qemu/qemu_monitor.c: Wire up JSON mode for qemuMonitorGetPtyPaths
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h: Fix
  const correctness. Add missing error message in the function
  qemuMonitorJSONGetAllPCIAddresses. Add implementation of the
  qemuMonitorGetPtyPaths function calling 'query-chardev'.

Hotunplug of devices requires that we know their PCI address. Even
hotplug of SCSI drives, required that we know the PCI address of
the SCSI controller to attach the drive to. We can find this out
by running 'info pci' and then correlating the vendor/product IDs
with the devices we booted with.

Although this approach is somewhat fragile, it is the only viable
option with QEMU < 0.12, since there is no way for libvirto set
explicit PCI addresses when creating devices in the first place.
For QEMU > 0.12, this code will not be used.

* src/qemu/qemu_driver.c: Assign all dynamic PCI addresses on
  startup of QEMU VM, matching vendor/product IDs
* 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
  API for fetching PCI device address mapping

The current SCSI hotplug support attaches a brand new SCSI controller
for every disk. This is broken because the semantics differ from those
used when starting the VM initially. In the latter case, each SCSI
controller is filled before a new one is added.

If the user specifies an high drive index (sdazz) then at initial
startup, many intermediate SCSI controllers may be added with no
drives.

This patch changes SCSI hotplug so that it exactly matches the
behaviour of initial startup. First the SCSI controller number is
determined for the drive to be hotplugged. If any controller upto
and including that controller number is not yet present, it is
attached. Then finally the drive is attached to the last controller.

NB, this breaks SCSI hotunplug, because there is no 'drive_del'
command in current QEMU. Previous SCSI hotunplug was broken in
any case because it was unplugging the entire controller, not
just the drive in question.

A future QEMU will allow proper SCSI hotunplug of a drive.

This patch is derived from work done by Wolfgang Mauerer on disk
controllers.

* src/qemu/qemu_driver.c: Fix SCSI hotplug to add a drive to
 the correct controller, instead of just attaching a new
  controller.
* 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
  support for 'drive_add' command

This patch allows for explicit hotplug/unplug of SCSI controllers.
Ordinarily this is not required, since QEMU/libvirt will attach
a new SCSI controller whenever one is required. Allowing explicit
hotplug of controllers though, enables the caller to specify a
static PCI address, instead of auto-assigning the next available
PCI slot. Or it will when we have static PCI addressing.

This patch is derived from Wolfgang Mauerer's disk controller
patch series.

* src/qemu/qemu_driver.c: Support hotplug & unplug of SCSI
  controllers
* 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
  new API for attaching PCI SCSI controllers

Convert the QEMU monitor APIs over to use virDomainDeviceAddress
structs for passing addresses in/out, instead of individual bits.
This makes the number of parameters smaller & easier to deal with.
No functional change

* src/qemu/qemu_driver.c, src/qemu/qemu_monitor.c,
  src/qemu/qemu_monitor.h, src/qemu/qemu_monitor_text.c,
  src/qemu/qemu_monitor_text.h: Change monitor hotplug APIs to
  take an explicit address ptr for all host/guest addresses

Initial support for the new QEMU monitor protocol  using JSON
as the data encoding format instead of plain text

* po/POTFILES.in: Add src/qemu/qemu_monitor_json.c
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Hack to turn on QMP
  mode. Replace with a version number check on >= 0.12 later
* src/qemu/qemu_monitor.c: Delegate to json monitor if enabled
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h: Add
  impl of QMP protocol
* src/Makefile.am: Add src/qemu/qemu_monitor_json.{c,h}

The current QEMU disk media change does not support setting the
disk format. The new JSON monitor will support this, so add an
extra parameter to pass this info in

* src/qemu/qemu_driver.c: Pass in disk format when changing media
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c,
  src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
  Add a 'format' arg to qemuMonitorChangeMedia()

Change the QEMU monitor file handle watch to poll for both
read & write events, as well as EOF. All I/O to/from the
QEMU monitor FD is now done in the event callback thread.

When the QEMU driver needs to send a command, it puts the
data to be sent into a qemuMonitorMessagePtr object instance,
queues it for dispatch, and then goes to sleep on a condition
variable. The event thread sends all the data, and then waits
for the reply to arrive, putting the response / error data
back into the qemuMonitorMessagePtr and notifying the condition
variable.

There is a temporary hack in the disk passphrase callback to
avoid acquiring the domain lock.  This avoids a deadlock in
the command processing, since the domain lock is still held
when running monitor commands. The next commit will remove
the locking when running commands & thus allow re-introduction
of locking the disk passphrase callback

* src/qemu/qemu_driver.c: Temporarily don't acquire lock in
  disk passphrase callback. To be reverted in next commit
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Remove
  raw I/O functions, and a generic qemuMonitorSend() for
  invoking a command
* src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
  Remove all low level I/O, and use the new qemuMonitorSend()
  API. Provide a qemuMonitorTextIOProcess() method for detecting
  command/reply/prompt boundaries in the monitor data stream

Change the QEMU driver to not directly invoke the text mode monitor
APIs. Instead add a generic wrapper layer, which will eventually
invoke either the text or JSON protocol code as needed. Pass an
qemuMonitorPtr object into the monitor APIs instead of virDomainObjPtr
to complete the de-coupling of the monitor impl from virDomainObj
data structures

* src/qemu/qemu_conf.h: Remove qemuDomainObjPrivate definition
* src/qemu/qemu_driver.c: Add qemuDomainObjPrivate definition.
  Pass qemuMonitorPtr into all monitor APIs instead of the
  virDomainObjPtr instance.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add thin
  wrappers for all qemuMonitorXXX command APIs, calling into
  qemu_monitor_text.c/h
* src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
  Rename qemuMonitor -> qemuMonitorText & update to accept
  qemuMonitorPtr instead of virDomainObjPtr

The upcoming tunnelled migration needs to be able to set
a migration in progress in the background, as well as
be able to cancel a migration when a problem has happened.
This patch allows for both of these to properly work.
Signed-off-by: NChris Lalancette <clalance@redhat.com>

* src/qemu/qemu_monitor_text.h: Remove qemudMonitorCommand,
  qemudMonitorCommandWithFd, qemudMonitorCommandWithHandler,
  qemudMonitorCommandExtra low level APIs
* src/qemu/qemu_monitor_text.c: Replace s/qemud/qemuMonitor/

* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Add new
  qemuMonitorRemoveHostNetwork() command for removing host
  networks
* src/qemu/qemu_driver.c: Convert NIC hotplug methods over
  to use qemuMonitorRemoveHostNetwork()

* src/qemu/qemu_conf.h, src/qemu/qemu_conf.c: Remove prefix arg
  from qemuBuildHostNetStr which is no longer required
* src/qemu/qemu_driver.c: Refactor to use qemuMonitorAddHostNetwork()
  API for adding host network
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorAddHostNetwork() method for adding host networks

* src/qemu/qemu_conf.c: Remove separator from qemuBuildNicStr()
  args, and remove hardcoded 'nic' prefix. Leave it upto callers
  instead
* src/qemu/qemu_driver.c: Switch over to using the new
  qemuMonitorAddPCINetwork() method for NIC hotplug
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorAddPCINetwork API for PCI network device hotplug

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorCloseFileHandle and qemuMonitorSendFileHandle
  APIs for processing file handles
* src/qemu/qemu_driver.c: Convert NIC hotplug method over to
  use   qemuMonitorCloseFileHandle and qemuMonitorSendFileHandle

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  API qemuMonitorAddPCIDisk()
* src/qemu/qemu_driver.c: Convert over to using the new
  qemuMonitorAddPCIDisk() method, and remove now obsolete
  qemudEscape() method

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new API
  qemuMonitorRemovePCIDevice() for removing PCI device
* src/qemu/qemu_driver.c: Convert all places removing PCI devices
  over to new qemuMonitorRemovePCIDevice() API

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  API qemuMonitorAddPCIHostDevice()
* src/qemu/qemu_driver.c: Switch to using qemuMonitorAddPCIHostDevice()
  for PCI host device hotplug

One API adds an exact device based on bus+dev, the other adds
any device matching vendor+product

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorAddUSBDeviceExact() and qemuMonitorAddUSBDeviceMatch()
  commands.
* src/qemu/qemu_driver.c: Switch over to using the new
    qemuMonitorAddUSBDeviceExact() and qemuMonitorAddUSBDeviceMatch()

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorAddUSBDisk() API
* src/qemu/qemu_driver.c: Switch USB disk hotplug to the new
  src/qemu/qemu_driver.c API.

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorMigrateToCommand() API
* src/qemu/qemu_driver.c: Switch over to using the
  qemuMonitorMigrateToCommand() API for core dumps and save
  to file APIs

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new API
  qemuMonitorMigrateToHost() for doing TCP migration
* src/qemu/qemu_driver.c: Convert to use qemuMonitorMigrateToHost().
  Also handle proper URIs (tcp:// as well as tcp:)

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorGetMigrationStatus() command.
* src/qemu/qemu_driver.c: Use new qemuMonitorGetMigrationStatus()
  command to check completion status.

* src/qemu/qemu_driver.c: Use new qemuMonitorSetMigrationSpeed()
  API during migration
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Add new
  qemuMonitorSetMigrationSpeed() API

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add a new
  qemuMonitorGetBlockStatsInfo() command
* src/qemu/qemu_driver.c: Remove directly use of blockstats in
  favour of calling qemuMonitorGetBlockStatsInfo()