Instead of relying on QEMU to assign PCI addresses and then querying
them with 'info pci', manually assign all PCI addresses before starting
the guest.  These addresses are not stable across reboots. That will
come in a later patch

NB, the PIIX3 (IDE, FDC, ISA-Bridge) will always have slot 1 and
VGA will always have slot 2. We declare the Virtio Balloon gets
slot 3, and then all remaining slots are for configured devices.

* src/qemu/qemu_conf.c: If -device is supported, then assign all PCI
  addresses when building the command line
* src/qemu/qemu_driver.c: Don't query monitor for PCI addresses if
  they have already been assigned
* tests/qemuxml2argvdata/qemuxml2argv-hostdev-pci-address-device.args,
  tests/qemuxml2argvdata/qemuxml2argv-net-virtio-device.args,
  tests/qemuxml2argvdata/qemuxml2argv-sound-device.args,
  tests/qemuxml2argvdata/qemuxml2argv-watchdog-device.args: Update
  to include PCI slot/bus information

QEMU always configures a VGA card. If no video card is included in
the libvirt XML, it is neccessary to explicitly turn off the default
using -vga none

* src/qemu/qemu_conf.c: Pass -vga none if no video card is configured
* tests/qemuargv2xmltest.c, tests/qemuxml2argvtest.c: Test for
  handling -vga none.
* tests/qemuxml2argvdata/qemuxml2argv-nographics-vga.args,
  tests/qemuxml2argvdata/qemuxml2argv-nographics-vga.xml: Test
  data files

Not all QEMU builds default to SDL graphics for their display.
Newer QEMU now has an explicit -sdl flag, which we can use to
explicitly request SDL intead of relying on the default. This
protects libvirt against unexpected changes in graphics default

* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Probe for -sdl
  flag and use it if it is found
* tests/qemuhelptest.c: Add SDL flag to tests

The old syntax was

   -chardev SOMECONFIG
   -nic user,guestfwd=tcp:IP:PORT-chardev:CHARDEV

The new syntax is

   -chardev SOMECONFIG
   -netdev user,guestfwd=tcp:IP:PORT,chardev=ID,id=user-ID

The old syntax is

  -pcidevice host=BUS:SLOT:FUNCTION

The new syntax is

  -device pci-assign,host=BUS:SLOT:FUNCTION,addr=<PCI SLOT>,id=host0

The old syntax was

   -usbdevice host:PRODUCT:VENDOR

Or

   -usbdevice host:BUS.DEV

The new syntax is

   -device usb-host,product=PRODUCT,vendor=VENDOR

Or

   -device usb-host,hostbus=BUS,hostaddr=DEV

The previous syntax was severely limited in its options

  -usbdevice disk:/home/berrange/output.img

The new syntax is the same as for other disk types

  -drive file=/home/berrange/output.img,if=none,id=usb-1,index=1
  -device usb-storage,drive=usb-1

Again, the index= arg is wrong here, and will be removed in a
later merge

The current syntax uses a pair of args

   -net nic,macaddr=52:54:00:56:6c:55,vlan=3,model=pcnet,name=pcnet.0
   -net user,vlan=3,name=user.0

The new syntax does not  need the vlan craziness anymore, and
so has a simplified pair of args

   -netdev user,id=user.0
   -device pcnet,netdev=user.0,id=pcnet.0,mac=52:54:00:56:6c:55,addr=<PCI SLOT>

The current preferred syntax for disk drives uses

  -drive file=/vms/plain.qcow,if=virtio,index=0,boot=on,format=qcow

The new syntax splits this up into a pair of linked args

  -drive file=/vms/plain.qcow,if=none,id=drive-virtio-0,format=qcow2
  -device virtio-blk-pci,drive=drive-virtio-0,id=virtio-0,addr=<PCI SLOT>

SCSI/IDE devices also get a bus property linking them to the
controller

  -device scsi-disk,drive=drive-scsi0-0-0,id=scsi0-0-0,bus=scsi0.0,scsi-id=0
  -device ide-drive,drive=drive-ide0-0-0,id=ide0-0-0,bus=ide0,unit=0

The current syntax for audio devices is a horrible multiplexed
arg

    -soundhw sb16,pcspk,ac97

The new syntax is

    -device sb16,id=sound0

or

    -device AC97,id=sound1,addr=<PCI SLOT>

NB, pcspk still uses the old -soundhw syntax

The current syntax for watchdogs is

    -watchdog i6300esb

The new syntax will now be

    -device i6300esb,id=watchdogNN,addr=<PCI-SLOT>

The current character device syntax uses either

  -serial tty,path=/dev/ttyS2

Or

  -chardev tty,id=serial0,path=/dev/ttyS2 -serial chardev:serial0

With the new -device support, we now prefer

  -chardev file,id=serial0,path=/tmp/serial.log -device isa-serial,chardev=serial0

This patch changes the existing -chardev syntax to use this new
scheme, and fallbacks to the old plain -serial syntax for old
QEMU.

The monitor device changes to

  -chardev socket,id=monitor,path=/tmp/test-monitor,server,nowait -mon chardev=monitor

In addition, this patch adds --nodefaults, which kills off the
default serial, parallel, vga and nic devices. THis avoids the
need for us to explicitly turn each off

When starting a guest, give every device a unique alias. This will
be used for the 'id' parameter in -device args in later patches.
It can also be used to uniquely identify devices in the monitor

For old QEMU without -device, assign disk names based on QEMU's
historical naming scheme.

* src/qemu/qemu_conf.c: Assign unique device aliases
* src/qemu/qemu_driver.c: Remove obsolete qemudDiskDeviceName
  and use the device alias in eject & blockstats commands

Probe for the new -device flag and if available set the -nodefaults
flag, instead of using -net none, -serial none or -parallel none.
Other device types will be converted to use -device in later patches.
The -nodefaults flag will help avoid unwelcome surprises from future
QEMU releases

* src/qemu/qemu_conf.c: Probe for -device. Add -nodefaults flag.
  Remove -net none, -serial none or -parallel none
* src/qemu/qemu_conf.h: Define QEMU_CMD_FLAG_DEVICE
* tests/qemuhelpdata/qemu-0.12.1: New data file for 0.12.1 QEMU
* tests/qemuhelptest.c: Test feature extraction from 0.12.1 QEMU

This patch introduces the support for giving all devices a short,
unique name, henceforth known as a 'device alias'.  These aliases
are not set by the end user, instead being assigned by the hypervisor
if it decides it want to support this concept.

The QEMU driver sets them whenever using the -device arg syntax
and uses them for improved hotplug/hotunplug. it is the intent
that other APIs (block / interface stats & device hotplug) be
able to accept device alias names in the future.

The XML syntax is

   <alias name="video0"/>

This may appear in any type of device that supports device info.

* src/conf/domain_conf.c, src/conf/domain_conf.h: Add a 'alias'
  field to virDomainDeviceInfo struct & parse/format it in XML
* src/libvirt_private.syms: Export virDomainDefClearDeviceAliases
* src/qemu/qemu_conf.c: Replace use of "nic_name" field with the
  standard device alias
* src/qemu/qemu_driver.c: Clear device aliases at shutdown

Existing applications using libvirt are not aware of the disk
controller concept. Thus, after parsing the <disk> definitions
in the XML, it is neccessary to create <controller> elements
to satisfy all requested disks, as per their defined drive
addresses

* src/conf/domain_conf.c, src/conf/domain_conf.h,
  src/libvirt_private.syms: Add virDomainDefAddDiskControllers()
  method for populating disk controllers, and call it after
  parsing disk definitions.
* src/qemu/qemu_conf.c: Call virDomainDefAddDiskControllers()
  when doing ARGV -> XML conversion
* tests/qemuxml2argvdata/qemuxml2argv*.xml: Add disk controller
  data to all data files which don't have it already

The current code for using -drive simply sets the -drive 'index'
parameter. QEMU internally converts this to bus/unit depending
on the type of drive. This does not give us precise control over
the bus/unit assignment though. This change switches over to make
libvirt explicitly calculate the bus/unit number.

In addition bus/unit/index are actually irrelevant for VirtIO
disks, since each virtio disk is a separate PCI device. No disk
controller is involved.

Doing the conversion to bus/unit in libvirt allows us to correctly
attach SCSI controllers when required.

* src/qemu/qemu_conf.c: Specify bus/unit instead of index for
  disks
* tests/qemuxml2argvdata/qemuxml2argv-disk*.args: Switch over from
  using index=NNNN, to bus=NN, unit=NN for SCSI/IDE/Floppy disks

To enable it to be called from multiple locations, split out
the code for building the -drive arg string. This will be needed
by later patches which do drive hotplug, the conversion to use
-device, and the conversion to controller/bus/unit addressing

* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Add qemuBuildDriveStr
  for building -drive arg string

When parsing the <disk> element specification, if no <address>
is provided for the disk, then automatically assign one based on
the <target dev='sdXX'/> device name. This provides for backwards
compatability with existing applications using libvirt, while also
allowing new apps to have complete fine grained control.

* src/conf/domain_conf.h, src/conf/domain_conf.c,
  src/libvirt_private.syms: Add virDomainDiskDefAssignAddress()
  for assigning a controller/bus/unit address based on disk target
* src/qemu/qemu_conf.c: Call virDomainDiskDefAssignAddress() after
  generating XML from ARGV
* tests/qemuxml2argvdata/*.xml: Add in drive address information
  to all XML files

The -mem-prealloc flag should be used when using large pages
This ensures qemu tries to allocate all required memory immediately,
rather than when first used. The latter mode will crash qemu
if hugepages aren't available when accessed, while the former
should gracefully fallback to non-hugepages.

* src/qemu/qemu_conf.c: add -mem-prealloc flag to qemu command line
  when using large pages

The behavior for the qemu balloon device has changed.  Formerly, a virtio
balloon device was provided by default.  Now, '-balloon virtio' must be
specified on the command line to enable it.  This patch causes libvirt to
add '-balloon virtio' to the command line whenever the -balloon option is
available.
* src/qemu/qemu_conf.c src/qemu/qemu_conf.h: check for the new flag and
  add "-baloon vitio" to qemu command when needed
* tests/qemuhelptest.c: add the new flag for detection

* src/qemu/qemu_conf.h: Remove QEMU_CMD_FLAG_0_12 and just leave
  the lone JSON flag
* src/qemu/qemu_conf.c: Enable JSON on QEMU 0.13 or later, but
  leave it disabled for now

* src/qemu/qemu_conf.c: CPU models should be probed only if the
  a guest's XML contains CPU model, not each time a qemu command line
  is generated.

* src/qemu/qemu_conf.c src/qemu/qemu_conf.h src/qemu/qemu_driver.c:
  add the new entry point, extend capabilities and code to interract
  with qemu

Change -monitor, -serial and -parallel output to use -chardev if it is
available.
* src/qemu/qemu_conf.c: Update qemudBuildCommandLine to use -chardev where
  available.
* tests/qemuxml2argvtest.c tests/qemuxml2argvdata/: Add -chardev equivalents
  for all current serial and parallel tests.

Replace free(virBufferContentAndReset()) with virBufferFreeAndReset().
Update documentation and replace all remaining calls to free() with
calls to VIR_FREE(). Also add missing calls to virBufferFreeAndReset()
and virReportOOMError() in OOM error cases.

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}

* src/qemu/qemu_conf.c: Fix default disk type to be 'FILE'
  again, after previous commit accidentally changed it

Introduce a new type="dir"  mode for <disks> that allows use of
QEMU's  virtual FAT block device driver. eg

    <disk type='dir' device='floppy'>
      <source dir='/tmp/test'/>
      <target dev='fda' bus='fdc'/>
      <readonly/>
    </disk>

gets turned into

  -drive file=fat:floppy:/tmp/test,if=floppy,index=0

Only read-only disks are supported with virtual FAT mode

* src/conf/domain_conf.c, src/conf/domain_conf.h: Add type="dir"
* docs/schemas/domain.rng: Document new disk type
* src/xen/xend_internal.c, src/xen/xm_internal.c: Raise error for
  unsupported disk types
* tests/qemuxml2argvdata/qemuxml2argv-disk-cdrom-empty.args: Fix
  empty disk file handling
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fat.args,
  tests/qemuxml2argvdata/qemuxml2argv-disk-drive-fat.xml,
  tests/qemuxml2argvdata/qemuxml2argv-floppy-drive-fat.args,
  tests/qemuxml2argvdata/qemuxml2argv-floppy-drive-fat.xml
  tests/qemuxml2argvtest.c: Test QEMU vitual FAT driver
* src/qemu/qemu_conf.c: Support generating fat:/some/dir type
  disk args
* src/security/security_selinux.c: Temporarily skip labelling
  of directory based disks

Recent qemu releases require command option '-enable-qemu' in order
for the kvm functionality be activated. Libvirt needs to pass this flag
to qemu when starting a domain. Note that without the option,
even if both the kernel and qemu support KVM, KVM will not be activated
and VMs will be very slow.

* src/qemu/qemu_conf.h src/qemu/qemu_conf.c: parse the extra command
  line option from help and add it when running kvm
* tests/qemuhelptest.c: this modified the flags output for qemu-0.10.5
  and qemu-kvm-0.11.0-rc2 regression tests

* src/qemu/qemu_conf.c: Remove and inline qemudBuildCommandLineChrDevTargetStr

* src/conf/domain_conf.h src/conf/domain_conf.c: add the new entry in
  the enum and lists of virDomainDiskBus
* src/qemu/qemu_conf.c: same for virDomainDiskQEMUBus

* src/qemu/qemu_conf.c: don't initialize ebtables if
  disabled

* src/qemu/qemu_conf.c: Update qemudBuildCommandLineChrDevStr to use a
  virBuffer

* src/qemu_qemu_conf.c: Cleanup usage of virBuffer in qemudBuildCommandLine

allows the following to be specified in a domain:
<channel type='pipe'>
  <source path='/tmp/guestfwd'/>
  <target type='guestfwd' address='10.0.2.1' port='4600'/>
</channel>

* proxy/Makefile.am: add network.c as dep of domain_conf.c
* docs/schemas/domain.rng src/conf/domain_conf.[ch]: extend the domain
  schemas and the parsing/serialization side for the new construct

QEmu support will add the following on the qemu command line:
 -chardev pipe,id=channel0,path=/tmp/guestfwd
 -net user,guestfwd=tcp:10.0.2.1:4600-chardev:channel0

* src/qemu/qemu_conf.c: Add argument output for channel
* tests/qemuxml2(argv|xml)test.c: Add test for <channel> domain syntax

* src/qemu/qemu_conf.h: defines a new QEMUD_CMD_FLAG_CHARDEV flag
* src/qemu/qemu_conf.c: parse the output for -chardev and set flag
  appropriately