Commit 7c6fc394 introduced a regression in the XML produced for older
clients.  The argument at the time was that clients shouldn't be
depending on output-only data for something that is only going to
be triggered for a transient guest; but John Ferlan reported that
the automated testsuite was such a client.  It's better to be safe
than sorry by guaranteeing back-compat cruft.  Note that later
patches will be using <mirror> for active block commit, but there
we don't have to worry about back-compat.

* src/conf/domain_conf.c (virDomainDiskDefFormat): Restore old
style output when necessary.
* docs/schemas/domaincommon.rng: Validate back-compat style.
* docs/formatdomain.html.in: Update the documentation.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror-old.xml:
Update tests.
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror.xml: Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Now that we track a disk mirror as a virStorageSource, we might
as well update the XML to theoretically allow any type of
mirroring destination (not just a local file).  A later patch
will also be reusing <mirror> to track the block commit of the
top layer of a chain, which is another case where libvirt needs
to update the backing chain after the job is finally pivoted,
and since backing chains can have network backing files as the
destination to commit into, it makes more sense to display that
in the XML.

This patch changes output-only XML; it was already documented
that <mirror> does not affect a domain definition at this point
(because qemu doesn't provide persistent bitmaps yet).  Any
application that was starting a block copy job with older libvirt
and then relying on the domain XML to determine if it was
complete will no longer be able to access the file= and format=
attributes of mirror that were previously used.  However, this is
not going to be a problem in practice: the only time a block copy
job works is on a transient domain, and any app that is managing
a transient domain probably already does enough of its own
bookkeeping to know which file it is mirroring into without
having to re-read it from the libvirt XML.  The one thing that
was likely to be used in a mirroring job was the ready=
attribute, which is unchanged.  Meanwhile, I made sure the schema
and parser still accept the old format, even if we no longer
output it, so that upgrading from an older version of libvirt is
seamless.

* docs/schemas/domaincommon.rng (diskMirror): Alter definition.
* src/conf/domain_conf.c (virDomainDiskDefParseXML): Parse two
styles of mirror elements.
(virDomainDiskDefFormat): Output new style.
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror-old.xml: New
file, copied from...
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror.xml: ...here
before modernizing.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror-old*: New
files.
* tests/qemuxml2xmltest.c (mymain): Test both styles.
Signed-off-by: NEric Blake <eblake@redhat.com>

This patch implements formating and parsing code for the backing store
schema defined and documented by the previous patch.

This patch does not aim at providing full persistent storage of disk
backing chains yet. The formatter is supposed to provide the backing
chain detected when starting a domain and thus it is not formatted into
an inactive domain XML. The parser is implemented mainly for the purpose
of testing the XML generated by the formatter and thus it does not
distinguish between no backingStore element and an empty backingStore
element. This will have to change once we fully implement support for
user-supplied backing chains.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

<controller type='pci' index='0' model='pci-root'/>
is auto-added to pc* machine types.
Without this controller PCI bus 0 is not available and
no PCI addresses are assigned by default.

Since older libvirt supported PCI bus 0 even without
this controller, it is removed from the XML when migrating.

<vcpu> is not an optional node. The value for its 'placement'
actually always defaults to 'static' in the underlying codes.
(Even no 'cpuset' and 'placement' is specified, the domain
process will be pinned to all the available pCPUs).

In order to track a block copy job across libvirtd restarts, we
need to save internal XML that tracks the name of the file
holding the mirror.  Displaying this name in dumpxml might also
be useful to the user, even if we don't yet have a way to (re-)
start a domain with mirroring enabled up front.  This is done
with a new <mirror> sub-element to <disk>, as in:

    <disk type='file' device='disk'>
      <driver name='qemu' type='raw'/>
      <source file='/var/lib/libvirt/images/original.img'/>
      <mirror file='/var/lib/libvirt/images/copy.img' format='qcow2' ready='yes'/>
      ...
    </disk>

For now, the element is output-only, in live domains; it is ignored
when defining a domain or hot-plugging a disk (since those contexts
use VIR_DOMAIN_XML_INACTIVE in parsing).  The 'ready' attribute appears
when libvirt knows that the job has changed from the initial pulling
phase over to the mirroring phase, although absence of the attribute
is not a sure indicator of the current phase.  If we come up with a way
to make qemu start with mirroring enabled, we can relax the xml
restriction, and allow <mirror> (but not attribute 'ready') on input.
Testing active-only XML meant tweaking the testsuite slightly, but it
was worth it.

* docs/schemas/domaincommon.rng (diskspec): Add diskMirror.
* docs/formatdomain.html.in (elementsDisks): Document it.
* src/conf/domain_conf.h (_virDomainDiskDef): New members.
* src/conf/domain_conf.c (virDomainDiskDefFree): Clean them.
(virDomainDiskDefParseXML): Parse them, but only internally.
(virDomainDiskDefFormat): Output them.
* tests/qemuxml2argvdata/qemuxml2argv-disk-mirror.xml: New test file.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-mirror.xml: Likewise.
* tests/qemuxml2xmltest.c (testInfo): Alter members.
(testCompareXMLToXMLHelper): Allow more test control.
(mymain): Run new test.

Make it obvious to 'dumpxml' readers what unit we are using,
since our default of KiB for memory (1024) differs from qemu's
default of MiB; and differs from our use of bytes for storage.

Tests were updated via:

$ find tests/*data tests/*out -name '*.xml' | \
  xargs sed -i 's/<\(memory\|currentMemory\|hard_limit\|soft_limit\|min_guarantee\|swap_hard_limit\)>/<\1 unit='"'KiB'>/"
$ find tests/*data tests/*out -name '*.xml' | \
  xargs sed -i 's/<\(capacity\|allocation\|available\)>/<\1 unit='"'bytes'>/"

followed by a few fixes for the stragglers.

Note that with this patch, the RNG for <memory> still forbids
validation of anything except unit='KiB', since the code silently
ignores the attribute; a later patch will expand <memory> to allow
scaled input in the code and update the RNG to match.

* docs/schemas/basictypes.rng (unit): Add 'bytes'.
(scaledInteger): New define.
* docs/schemas/storagevol.rng (sizing): Use it.
* docs/schemas/storagepool.rng (sizing): Likewise.
* docs/schemas/domaincommon.rng (memoryKBElement): New define; use
for memory elements.
* src/conf/storage_conf.c (virStoragePoolDefFormat)
(virStorageVolDefFormat): Likewise.
* src/conf/domain_conf.h (_virDomainDef): Document unit used
internally.
* src/conf/storage_conf.h (_virStoragePoolDef, _virStorageVolDef):
Likewise.
* tests/*data/*.xml: Update all tests.
* tests/*out/*.xml: Likewise.
* tests/define-dev-segfault: Likewise.
* tests/openvzutilstest.c (testReadNetworkConf): Likewise.
* tests/qemuargv2xmltest.c (blankProblemElements): Likewise.

* src/conf/domain_conf.h: Add new member "target" to struct
  _virDomainDeviceDriveAddress.

* src/conf/domain_conf.c: Parse and format "target"

* Lots of tests (.xml) in tests/domainsnapshotxml2xmlout,
  tests/qemuxml2argvdata, tests/qemuxml2xmloutdata, and
  tests/vmx2xmldata/ are modified for newly introduced
  attribute "target" for address of "drive" type.

Some tools, such as virt-manager, prefers having the default USB
controller explicit in the XML document. This patch makes sure there
is one. With this patch, it is now possible to switch from USB1 to
USB2 from the release 0.9.1 of virt-manager.

Fix tests to pass with this change.

Use it in all places where a memory or storage request size is converted
to a larger granularity. This avoids requesting too small memory or storage
sizes that could result from the truncation done by a simple division.

This extends the round up fix in 6002e040
to the whole codebase.

Instead of reporting errors for odd values in the VMX code round them up.

Update the QEMU Argv tests accordingly as the original memory size 219200
isn't a even multiple of 1024 and is rounded up to 215 megabyte now. Change
it to 219100 and 219136. Use two different values intentionally to make
sure that rounding up works.

Update virsh.pod accordingly, as rounding down and rejecting are replaced
by rounding up.

To allow compatibility with older QEMU PCI device slot assignment
it is necessary to explicitly track the balloon device in the
XML. This introduces a new device

   <memballoon model='virtio|xen'/>

It can also have a PCI address, auto-assigned if necessary.

The memballoon will be automatically added to all Xen and QEMU
guests by default.

* docs/schemas/domain.rng: Add <memballoon> element
* src/conf/domain_conf.c, src/conf/domain_conf.h: parsing
  and formatting for memballoon device. Always add a memory
  balloon device to Xen/QEMU if none exists in XML
* src/libvirt_private.syms: Export memballoon model APIs
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Honour the
  PCI device address in memory balloon device
* tests/*: Update to test new functionality

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

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