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

Those were pointed by DanB in his review but not yet fixed

* src/qemu/qemu_driver.c: qemudWaitForMonitor() use EnterMonitorWithDriver()
  and ExitMonitorWithDriver() there
* src/qemu/qemu_monitor_text.c: checking fro strdu failure and hash
  table add error in qemuMonitorTextGetPtyPaths()

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 QEMU 0.10.0 release (and possibly other 0.10.x) has a bug where
it sometimes/often forgets to display the initial monitor greeting
line, soley printing a (qemu).  This in turn confuses the text
console parsing because it has a '(qemu)' it is not expecting. The
confusion results in a negative malloc. Bad things follow.

This re-writes the text console handling to be more robust. The key
idea is that it should only look for a (qemu), once it has seen the
original command echo'd back. This ensures it'll skip the bogus stray
(qemu) with broken QEMUs.

* src/qemu/qemu_monitor.c: Add some (disabled) debug code
* src/qemu/qemu_monitor_text.c: Re-write way command replies
  are detected

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()

* src/qemu/qemu_monitor_text.c: Add missing underscore in the
  migrate_cancel monitor command impl

The qemuMonitorEscape() method, and the VIR_ENUM for migration
status will be needed by the JSON monitor too, so move that code
into the shared qemu_monitor.c file instead of qemu_monitor_text.c

* src/qemu/qemu_monitor.h: Declare qemuMonitorMigrationStatus enum
  and qemuMonitorEscapeArg and qemuMonitorEscapeShell methods
* src/qemu/qemu_monitor.c: Implement qemuMonitorMigrationStatus enum
  and qemuMonitorEscapeArg and qemuMonitorEscapeShell methods
* src/qemu/qemu_monitor_text.c: Remove above methods/enum

* src/qemu/qemu_monitor.c src/qemu/qemu_monitor_text.c: cast size_t to
  int when passing to '%d'

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

Decouple the monitor code from the virDomainDefPtr structure
by moving the disk encryption lookup code back into the
qemu_driver.c file. Instead provide a function callback to
the monitor code which can be invoked to retrieve encryption
data as required.

* src/qemu/qemu_driver.c: Add findDomainDiskEncryption,
  and findVolumeQcowPassphrase. Pass address of the method
  findVolumeQcowPassphrase into qemuMonitorOpen()
* src/qemu/qemu_monitor.c: Associate a disk
  encryption function callback with the qemuMonitorPtr
  object.
* src/qemu/qemu_monitor_text.c: Remove findDomainDiskEncryption
  and findVolumeQcowPassphrase.

Introduce a new qemuDomainObjPrivate object which is used to store
the private QEMU specific data associated with each virDomainObjPtr
instance. This contains a single member, an instance of the new
qemuMonitorPtr object which encapsulates the QEMU monitor state.
The internals of the latter are private to the qemu_monitor* files,
not to be shown to qemu_driver.c

* src/qemu/qemu_conf.h: Definition of qemuDomainObjPrivate.
* src/qemu/qemu_driver.c: Register a functions for creating
  and freeing qemuDomainObjPrivate instances with the domain
  capabilities. Remove the qemudDispatchVMEvent() watch since
  I/O watches are now handled by the monitor code itself. Pass
  a new qemuHandleMonitorEOF() callback into qemuMonitorOpen
  to allow notification when the monitor quits.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Introduce
  the 'qemuMonitor' object. Temporarily add new APIs
  qemuMonitorWrite, qemuMonitorRead, qemuMonitorWaitForInput
  to allow text based monitor impl to perform I/O.
* src/qemu/qemu_monitor_text.c: Call APIs for reading/writing
  to monitor instead of accessing the file handle directly.

Fix migration, broken in two different ways by the QEMU monitor
abstraction.  Note that the QEMU console emits a "\r\n" as the
line-ending.

* src/qemu/qemu_monitor_text.c (qemuMonitorGetMigrationStatus):
Fix "info migrate" command and its output's parsing.

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.c: Always print command and reply
  in qemuMonitorCommandWithHandler. Print all args in each monitor
  command API & remove redundant relpy printing

* 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()