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

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

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

Support for memory statistics reporting is accepted for qemu inclusion.
Statistics are reported via the monitor command 'info balloon' as a comma
seprated list:

(qemu) info balloon
balloon: actual=1024,mem_swapped_in=0,mem_swapped_out=0,major_page_faults=88,minor_page_faults=105535,free_mem=1017065472,total_mem=1045229568

Libvirt, qemu, and the guest operating system may support a subset of the
statistics defined by the virtio spec.  Thus, only statistics recognized by
components will be reported.

* src/qemu/qemu_driver.c src/qemu/qemu_monitor_text.[ch]: implement the
  new entry point by using info balloon monitor command

This change makes the QEMU driver get pty paths from the output of the
monitor 'info chardev' command. This output is structured, and contains
both the name of the device and the path on the same line. This is
considerably more reliable than parsing the startup log output, which
requires the parsing code to know which order QEMU will print pty
information in.

Note that we still need to parse the log output as the monitor itself
may be on a pty. This should be rare, however, and the new code will
replace all pty paths parsed by the log output method once the monitor
is available.

* src/qemu/qemu_monitor.(c|h) src/qemu_monitor_text.(c|h): Implement
  qemuMonitorGetPtyPaths().
* src/qemu/qemu_driver.c: Get pty path information using
  qemuMonitorGetPtyPaths().

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()

* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Add new APIs
  qemuMonitorSaveVirtualMemory() and qemuMonitorSavePhysicalMemory()
* src/qemu/qemu_driver.c: Use the new qemuMonitorSaveVirtualMemory()
  and qemuMonitorSavePhysicalMemory() APIs

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new APis
  qemuMonitorChangeMedia and qemuMonitorEjectMedia. Pull in code
  for qemudEscape
* src/qemu/qemu_driver.c: Remove code that directly issues 'eject'
  and 'change' commands in favour of API calls.

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add new
  qemuMonitorSetBalloon() based on existing code in
  qemudDomainSetMemoryBalloon
* src/qemu/qemu_driver.c: Remove use of qemudDomainSetMemoryBalloon()
  in favour of qemuMonitorSetBalloon(). Fix error code when balloon
  is not supported

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Pull old
  qemudDomainGetMemoryBalloon() code into a new method called
  qemuMonitorGetBalloonInfo()
* src/qemu/qemu_driver.c: Update to call qemuMonitorGetBalloonInfo()
  and remove qemudDomainGetMemoryBalloon().

* src/qemu/qemu_driver.c: Remove use of 'system_powerdown'
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Add a new
  qemuMonitorSystemPowerdown() api call

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add a new
  qemuMonitorStopCPUs() API
* src/qemu/qemu_driver.c: Replace direct monitor commands for 'stop'
  with qemuMonitorStopCPUs()

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Rename
  Rename qemudMonitorSendCont to qemuMonitorStartCPUs
* src/qemu/qemu_driver.c: Update callers for new name

* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add a
  new qemuMonitorSetVNCPassword() API
* src/qemu/qemu_driver.c: Refactor qemudInitPasswords to
  call qemuMonitorSetVNCPassword()

* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Add a new
  qemuMonitorGetCPUInfo() command
* src/qemu/qemu_driver.c: Refactor qemudDetectVcpuPIDs to
  use qemuMonitorGetCPUInfo()

Pull out all the QEMU monitor interaction code to a separate
file. This will make life easier when we need to drop in a
new implementation for the forthcoming QMP machine friendly
monitor support.

Next step is to add formal APIs for each monitor command,
and remove direct commands for sending/receiving generic
data.

* src/Makefile.am: Add qemu_monitor.c to build
* src/qemu/qemu_driver.c: Remove code for monitor interaction
* src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: New
  file for monitor interaction
* po/POTFILES.in: Add src/qemu/qemu_monitor_text.c