Add 'nocow' to storage volume xml so that user can have an option
to set NOCOW flag to the newly created volume. It's useful on btrfs
file system to enhance performance.

Btrfs has low performance when hosting VM images, even more when the guest
in those VM are also using btrfs as file system. One way to mitigate this
bad performance is to turn off COW attributes on VM files. Generally, there
are two ways to turn off COW on btrfs: a) by mounting fs with nodatacow,
then all newly created files will be NOCOW. b) per file. Add the NOCOW file
attribute. It could only be done to empty or new files.

This patch tries the second way, according to 'nocow' option, it could set
NOCOW flag per file:
for raw file images, handle 'nocow' in libvirt code; for non-raw file images,
pass 'nocow=on' option to qemu-img, and let qemu-img to handle that (requires
qemu-img version >= 2.1).
Signed-off-by: NChunyan Liu <cyliu@suse.com>

This new module holds and formats capabilities for emulator. If you
are about to create a new domain, you may want to know what is the
host or hypervisor capable of. To make sure we don't regress on the
XML, the formatting is not something left for each driver to
implement, rather there's general format function.

The domain capabilities is a lockable object (even though the locking
is not necessary yet) which uses reference counter.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This introduces two new attributes "cmd_per_lun" and "max_sectors" same
with the names QEMU uses for virtio-scsi. An example of the XML:

<controller type='scsi' index='0' model='virtio-scsi' cmd_per_lun='50'
max_sectors='512'/>

The corresponding QEMU command line:

-device virtio-scsi-pci,id=scsi0,cmd_per_lun=50,max_sectors=512,
bus=pci.0,addr=0x3
Signed-off-by: NMike Perez <thingee@gmail.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

The interface state for bonds and vlans does seem to reflect the state
of the underlying physical devices, at least in some cases, so it
makes sense to allow reporting it (netcf now does).

The link state/speed for bridge devices is meaningless though, so we
don't even look for it.

The interface xml schema was written with strict rules about the
ordering of the elements. This was never intentional, but just due to
omission of <interleave> in the appropriate places. This patch just
adds in <interleave> wherever there is more than one element, and
re-indents everything else appropriately.

There are two places where you'll find info on page sizes. The first
one is under <cpu/> element, where all supported pages sizes are
listed. Then the second one is under each <cell/> element which refers
to concrete NUMA node. At this place, the size of page's pool is
reported. So the capabilities XML looks something like this:

<capabilities>

  <host>
    <uuid>01281cda-f352-cb11-a9db-e905fe22010c</uuid>
    <cpu>
      <arch>x86_64</arch>
      <model>Westmere</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='1' threads='1'/>
      ...
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='2048'/>
      <pages unit='KiB' size='1048576'/>
    </cpu>
    ...
    <topology>
      <cells num='4'>
        <cell id='0'>
          <memory unit='KiB'>4054408</memory>
          <pages unit='KiB' size='4'>1013602</pages>
          <pages unit='KiB' size='2048'>3</pages>
          <pages unit='KiB' size='1048576'>1</pages>
          <distances/>
          <cpus num='1'>
            <cpu id='0' socket_id='0' core_id='0' siblings='0'/>
          </cpus>
        </cell>
        <cell id='1'>
          <memory unit='KiB'>4071072</memory>
          <pages unit='KiB' size='4'>1017768</pages>
          <pages unit='KiB' size='2048'>3</pages>
          <pages unit='KiB' size='1048576'>1</pages>
          <distances/>
          <cpus num='1'>
            <cpu id='1' socket_id='0' core_id='0' siblings='1'/>
          </cpus>
        </cell>
        ...
      </cells>
    </topology>
    ...
  </host>

  <guest/>

</capabilities>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

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>

This new element is there to represent PCI-Express capabilities
of a PCI devices, like link speed, number of lanes, etc.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

While exposing the info under <interface/> in previous patch works, it
may work only in cases where interface is configured on the host.
However, orchestrating application may want to know the link state and
speed even in that case. That's why we ought to expose this in nodedev
XML too:

virsh # nodedev-dumpxml net_eth0_f0_de_f1_2b_1b_f3
<device>
  <name>net_eth0_f0_de_f1_2b_1b_f3</name>
  <path>/sys/devices/pci0000:00/0000:00:19.0/net/eth0</path>
  <parent>pci_0000_00_19_0</parent>
  <capability type='net'>
    <interface>eth0</interface>
    <address>f0:de:f1:2b:1b:f3</address>
    <link speed='1000' state='up'/>
    <capability type='80203'/>
  </capability>
</device>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Currently it is not possible to determine the speed of an interface
and whether a link is actually detected from the API. Orchestrating
platforms want to be able to determine when the link has failed and
where multiple speeds may be available which one the interface is
actually connected at. This commit introduces an extension to our
interface XML (without implementation to interface driver backends):

  <interface type='ethernet' name='eth0'>
    <start mode='none'/>
    <mac address='aa:bb:cc:dd:ee:ff'/>
    <link speed='1000' state='up'/>
    <mtu size='1492'/>
    ...
  </interface>

Where @speed is negotiated link speed in Mbits per second, and state
is the current NIC state (can be one of the following:  "unknown",
"notpresent", "down", "lowerlayerdown","testing", "dormant", "up").
Signed-off-by: NMichal Privoznik <mprivozn@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>

A PCI device can be associated with a specific NUMA node. Later, when
a guest is pinned to one NUMA node the PCI device can be assigned on
different NUMA node. This makes DMA transfers travel across nodes and
thus results in suboptimal performance. We should expose the NUMA node
locality for PCI devices so management applications can make better
decisions.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

If user or management application wants to create a guest,
it may be useful to know the cost of internode latencies
before the guest resources are pinned. For example:

<capabilities>

  <host>
    ...
    <topology>
      <cells num='2'>
        <cell id='0'>
          <memory unit='KiB'>4004132</memory>
          <distances>
            <sibling id='0' value='10'/>
            <sibling id='1' value='20'/>
          </distances>
          <cpus num='2'>
            <cpu id='0' socket_id='0' core_id='0' siblings='0'/>
            <cpu id='2' socket_id='0' core_id='2' siblings='2'/>
          </cpus>
        </cell>
        <cell id='1'>
          <memory unit='KiB'>4030064</memory>
          <distances>
            <sibling id='0' value='20'/>
            <sibling id='1' value='10'/>
          </distances>
          <cpus num='2'>
            <cpu id='1' socket_id='0' core_id='0' siblings='1'/>
            <cpu id='3' socket_id='0' core_id='2' siblings='3'/>
          </cpus>
        </cell>
      </cells>
    </topology>
    ...
  </host>
  ...
</capabilities>

We can see the distance from node1 to node0 is 20 and within nodes 10.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

ppce500v2 is not machine supported by official release of QEMU.
It should be replaced by ppce500.
Signed-off-by: NJán Tomko <jtomko@redhat.com>

The XML for quite a longish backing chain is shown below:

  <disk type='network' device='disk'>
    <driver name='qemu' type='qcow2'/>
    <source protocol='nbd' name='bar'>
      <host transport='unix' socket='/var/run/nbdsock'/>
    </source>
    <backingStore type='block' index='1'>
      <format type='qcow2'/>
      <source dev='/dev/HostVG/QEMUGuest1'/>
      <backingStore type='file' index='2'>
        <format type='qcow2'/>
        <source file='/tmp/image2.qcow'/>
        <backingStore type='file' index='3'>
          <format type='qcow2'/>
          <source file='/tmp/image3.qcow'/>
          <backingStore type='file' index='4'>
            <format type='qcow2'/>
            <source file='/tmp/image4.qcow'/>
            <backingStore type='file' index='5'>
              <format type='qcow2'/>
              <source file='/tmp/image5.qcow'/>
              <backingStore type='file' index='6'>
                <format type='raw'/>
                <source file='/tmp/Fedora-17-x86_64-Live-KDE.iso'/>
                <backingStore/>
              </backingStore>
            </backingStore>
          </backingStore>
        </backingStore>
      </backingStore>
    </backingStore>
    <target dev='vdb' bus='virtio'/>
  </disk>

Various disk types and formats can be mixed in one chain. The
<backingStore/> empty element marks the end of the backing chain and it
is there mostly for future support of parsing the chain provided by a
user. If it's missing, we are supposed to probe for the rest of the
chain ourselves, otherwise complete chain was provided by the user. The
index attributes of backingStore elements can be used to unambiguously
identify a specific part of the image chain.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

I noticed that depending on the <driver> attributes the user passed
in, the output may omit the <driver> element altogether.  For example,
the rerror_policy has had this problem since commit 4bb4109f in Oct
2011.  But in adding testsuite coverage to expose it, I found another
problem: the C code is just fine without a driver name, but the
XML validator required either a name or a cache mode.

* src/conf/domain_conf.c (virDomainDiskDefFormat): Update
conditional.
* docs/schemas/domaincommon.rng (diskDriver): Simplify.
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-copy-on-read.xml:
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-copy-on-read.args:
New files.
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-discard.xml:
Enhance test.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-discard.xml:
Likewise.
* tests/qemuxml2argvtest.c (mymain): New test.
* tests/qemuxml2xmltest.c (mymain): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

To make <disk> schema more maintainable and to allow for moving the
pieces to a common file in the future. It relies on the ability to
override definitions as part of an include, set up in the previous
patch.

The diff is a bit hard to read, because it mixes reindentation
with refactoring; 'git diff -b --patience' may help.

* docs/schemas/domaincommon.rng (disk): Refactor into pieces.
(diskSource, diskSourceFile, diskSourceBlock, diskSourceDir)
(diskSourceVolume: New defines.
(diskSourceNetwork): Revise scope.
* docs/schemas/domainsnapshot.rng (disksnapshot): Adjust.
* tests/domainsnapshotxml2xmlin/disk-seclabel-invalid.xml,
tests/domainsnapshotxml2xmlin/disk-network-seclabel-invalid.xml: New
tests to check seclabel is forbidden in domain snapshot by schema.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

This patch is my first experience playing with nested grammars,
as documented in http://relaxng.org/tutorial-20011203.html#IDA3PZR.
I plan on doing more overrides in order to make the RelaxNG
grammar mirror the C code refactoring into a common
virStorageSource, but where different clients of that source do
not support the same subset of functionality.  By starting with
something fairly easy to validate, I can make sure my later
patches will be possible.

This patch adds a use of the no-op <ref
name='sourceStartupPolicy'/> to the disksnapshot definition, so
that the snapshot version of a type='file' <source> more closely
resembles the version in domaincommon.  A future patch will merge
the two files into using a common define, but this patch is
sufficient for testing that adding <source
startupPolicy='optional'/> in any of the
tests/domainsnapshotxml2xmlin/*.xml files still gets rejected
unless it occurs within the <domain> subelement, because the
definition of startupPolicy is empty outside of domain.rng.

* docs/schemas/storagecommon.rng (storageStartupPolicy)
(storageSourceExtra): Create no-op defaults.
* docs/schemas/domainsnapshot.rng (domain): Use nested grammar
to avoid restricting <domain>.
(storageSourceExtra): Create new override.
(disksnapshot): Access overrides through common names.
* docs/schemas/domaincommon.rng (disk): Access overrides through
common names.
* docs/schemas/domain.rng (storageStartupPolicy)
(storageSourceExtra): Create new overrides.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Domain snapshots should only permit an external snapshot into
a storage format that permits a backing chain, since the new
snapshot file necessarily must be backed by the existing file.
The C code for the qemu driver is a little bit stricter in
currently enforcing only qcow2 or qed, but at the XML parser
level, including virt-xml-validate, it is fairly easy to
enforce that a user can't request a 'raw' external snapshot.

* docs/schemas/storagecommon.rng (storageFormat): Split out...
(storageFormatBacking): ...new sublist.
* docs/schemas/domainsnapshot.rng (disksnapshotdriver): Use new
type.
* src/util/virstoragefile.h (virStorageFileFormat): Rearrange for
easier code management.
* src/util/virstoragefile.c (virStorageFileFormat, fileTypeInfo):
Likewise.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefParseXML): Use
new marker to limit selection of formats.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

We had incomplete RelaxNG support for storage formats listed
in virstoragefile.h: commit 027bf2ea added 'vdi' but forgot
to update the <volume> and <domain> xml lists; the <volume>
list was also missing 'fat' and 'vhd'.  Maintaining two lists
is a recipe for them getting out of sync, so make the list
common so that both contexts benefit the next time we add a
format in a single location.

* docs/schemas/domaincommon.rng (storageFormat): Move...
* docs/schemas/storagecommon.rng: ...here, and add vdi.
* docs/schemas/storagevol.rng (formatfile): Use common list.
Signed-off-by: NEric Blake <eblake@redhat.com>

In general, we try to make virt-xml-validate tolerant of input
elements in any order when possible.  However, as written, the
RNG grammar did not permit <source> unless there was an explicit
type= attribute (even though the C code manages just fine by
defaulting to type='file').  After making the attribute optional
on the 'file' branch, I noticed that the use of diskspec was now
redundant with the branch when no <source> was supplied.

View this patch with 'git diff -b' for a better picture of the
schema change.

* docs/schemas/domaincommon.rng (disk): Hoist 'diskspec' out of
choice, make type='file' default, and still preserve interleave.
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-source-pool.xml:
* tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-discard.xml:
New files.
* tests/qemuxml2argvdata/qemuxml2argv-disk-source-pool.xml:
* tests/qemuxml2argvdata/qemuxml2argv-disk-drive-discard.xml:
Reorder XML.
* tests/qemuxml2xmltest.c (mymain): Cover new files.
Signed-off-by: NEric Blake <eblake@redhat.com>

Having two tiny files with a couple definitions didn't make
as much sense as one common file, especially since I plan to
add more definitions and use it in more places.

* docs/schemas/storageencryption.rng: Merge this...
* docs/schemas/storagefilefeatures.rng: ...and this, into...
* docs/schemas/storagecommon.rng: ...this new file.
* docs/schemas/Makefile.am (schema_DATA): Reflect renames.
* docs/schemas/storagevol.rng: Likewise.
* docs/schemas/domaincommon.rng: Likewise.
* libvirt.spec.in: Likewise.
* mingw-libvirt.spec.in: Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

This patch adds an element to QEMU's capability XML, to
show if the underlying QEMU binary supports the live disk
snapshotting or not.
This allows any client to know ahead of time if the feature
is available.

Without this information available, the only way to check
for the snapshot support is to request one and check for
errors.
Signed-off-by: NFrancesco Romani <fromani@redhat.com>

Add VIR_DOMAIN_HOSTDEV_PCI_BACKEND_XEN. For legacy xen, it will use "pciback" as
stub driver.

There is no keyboard support currently in libvirt.

For some platforms (PPC64 QEMU) this makes graphics unusable,
since the keyboard is not implicit and it can't be added via libvirt.
Signed-off-by: NLi Zhang <zhlcindy@linux.vnet.ibm.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

Add a new character device backend called 'spiceport' that uses
spice's channel for communications and apart from spicevmc can be used
as a backend for any character device from libvirt's point of view.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Add a new <timer> for the HyperV reference time counter enlightenment
and the iTSC reference page for Windows guests.

This feature provides a paravirtual approach to track timer events for
the guest (similar to kvmclock) with the option to use real hardware
clock on systems with a iTSC with compensation across various hosts.

According to the documentation describing various tunables for domain
timers not all the fields are supported by all the driver types. Express
these in the RNG:

- rtc, platform: Only these support the "track" attribute.
- tsc: only one to support "frequency" and "mode" attributes
- hpet, pit: tickpolicy/catchup attribute/element
- kvmclock: no extra attributes are supported

Additionally the attributes of the <catchup> element for
tickpolicy='catchup' are optional according to the parsing code. Express
this in the XML and fix a spurious space added while formatting the
<catchup> element and add tests for it.

Add support for specifying various types when doing snapshots. This will
later allow to do snapshots on network backed volumes. Disks of type
'volume' are not supported by snapshots (yet).

Also amend the test suite to check parsing of the various new disk
types that can now be specified.

spice-server offers an API to disable file transfer messages
on the agent channel between the client and the guest.
This is supported in qemu through the disable-agent-file-xfer option.

This patch exposes this option to libvirt.
Adds a new element 'filetransfer', with one property,
'enable', which accepts a boolean.
Default is enabled, for backward compatibility.

Depends on the capability exported in the first patch of the series.
Signed-off-by: NFrancesco Romani <fromani@redhat.com>

This patch introduces new xml elements under <blkiotune>,
we use these new elements to setup the throttle blkio
cgroup for domain. The new blkiotune node looks like this:

<blkiotune>
  <device>
    <path>/path/to/block</path>
    <weight>1000</weight>
    <read_iops_sec>10000</read_iops_sec>
    <write_iops_sec>10000</write_iops_sec>
    <read_bytes_sec>1000000</read_bytes_sec>
    <write_bytes_sec>1000000</write_bytes_sec>
  </device>
</blkiotune>
Signed-off-by: NGuan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>

When idmap was added to LXC, we forgot to cover it in the testsuite.
The schema was missing an <element> layer, and as a result,
virt-xml-validate was failing on valid dumpxml output.

Reported by Eduard - Gabriel Munteanu on IRC.

* docs/schemas/domaincommon.rng (idmap): Include <idmap> element,
and support interleaves.
* tests/lxcxml2xmldata/lxc-idmap.xml: New file.
* tests/lxcxml2xmltest.c (mymain): Test it.
Signed-off-by: NEric Blake <eblake@redhat.com>

AArch64 qemu has similar behavior as armv7l, like use of mmio etc.
This patch adds similar bypass checks what we have for armv7l to aarch64.
E.g. we are enabling mmio transport for Nicdev.
Making addDefaultUSB and addDefaultMemballoon to false etc.

V3:
- Adding missing domain rng schema for aarcg64 and test case in
  testutilsqemu.c which was causing test suite failure
  while running make check.

V2:
- Added testcase to qemuxml2argvtest as suggested
  during review comments of V1.

V1:
- Initial patch.
Signed-off-by: NAnup Patel <anup.patel@linaro.org>
Signed-off-by: NPranavkumar Sawargaonkar <pranavkumar@linaro.org>

Extract the definition to a new type to allow avoiding of duplication.

panic device is a device that enables libvirt to receive notification
of guest panic event.
Signed-off-by: NEric Blake <eblake@redhat.com>

For example:
<address type='isa' iobase='0x505' irq='0x1'/>
Signed-off-by: NEric Blake <eblake@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1035118

When outputting the XML for the RNG device, the code didn't format the
PCI address info. Additionally the schema wasn't expecting the info
although it was being parsed and used internally. Fix those mistakes and
add test for the PCI info section.

In the 'directory' and 'netfs' storage pools, a user can see
both 'file' and 'dir' storage volume types, to know when they
can descend into a subdirectory.  But in a network-based storage
pool, such as the upcoming 'gluster' pool, we use 'network'
instead of 'file', and did not have any counterpart for a
directory until this patch.  Adding a new volume type
'network-dir' is better than reusing 'dir', because it makes
it clear that the only way to access 'network' volumes within
that container is through the network mounting (leaving 'dir'
for something accessible in the local file system).

* include/libvirt/libvirt.h.in (virStorageVolType): Expand enum.
* docs/formatstorage.html.in: Document it.
* docs/schemasa/storagevol.rng (vol): Allow new value.
* src/conf/storage_conf.c (virStorageVol): Use new value.
* src/qemu/qemu_command.c (qemuBuildVolumeString): Fix client.
* src/qemu/qemu_conf.c (qemuTranslateDiskSourcePool): Likewise.
* tools/virsh-volume.c (vshVolumeTypeToString): Likewise.
* src/storage/storage_backend_fs.c
(virStorageBackendFileSystemVolDelete): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Add support for a new <pool type='gluster'>, similar to
RBD and Sheepdog.  Terminology wise, a gluster volume
forms a libvirt storage pool, within the gluster volume,
individual files are treated as libvirt storage volumes.

* docs/schemas/storagepool.rng (poolgluster): New pool type.
* docs/formatstorage.html.in: Document gluster.
* docs/storage.html.in: Likewise, and contrast it with netfs.
* tests/storagepoolxml2xmlin/pool-gluster.xml: New test.
* tests/storagepoolxml2xmlout/pool-gluster.xml: Likewise.
* tests/storagepoolxml2xmltest.c (mymain): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

I got annoyed at having to use both 'virsh vol-list $pool --details'
AND 'virsh vol-dumpxml $vol $pool' to learn if I had populated
the volume correctly.  Since two-thirds of the data present in
virStorageVolGetInfo() already appears in virStorageVolGetXMLDesc(),
this just adds the remaining piece of information, as:

<volume type='...'>
  ...
</volume>

* docs/formatstorage.html.in: Document new <volume type=...>.
* docs/schemas/storagevol.rng (vol): Add it to RelaxNG.
* src/conf/storage_conf.h (virStorageVolTypeToString): Declare.
* src/conf/storage_conf.c (virStorageVolTargetDefFormat): Output
the metatype.
(virStorageVolDefParseXML): Parse it, for unit tests.
* tests/storagevolxml2xmlout/vol-*.xml: Update tests to match.
Signed-off-by: NEric Blake <eblake@redhat.com>