The VxHS block device will only use the newer formatting options and
avoid the legacy URI syntax.

An excerpt for a sample QEMU command line is:

  -drive file.driver=vxhs,file.vdisk-id=eb90327c-8302-4725-9e1b-4e85ed4dc251,\
   file.server.type=tcp,file.server.host=192.168.0.1,\
   file.server.port=9999,format=raw,if=none,id=drive-virtio-disk0,cache=none \
  -device virtio-blk-pci,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,\
   id=virtio-disk0

Update qemuxml2argvtest with a simple test.
Signed-off-by: NAshish Mittal <Ashish.Mittal@veritas.com>
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Extract out the "guts" of building a server entry into it's own
separately callable/usable function in order to allow building
a server entry for a consumer with src->nhosts == 1.

Add a new virStorageNetProtocol for Veritas HyperScale (VxHS) disks
Signed-off-by: NAshish Mittal <Ashish.Mittal@veritas.com>
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Store the 'drv' field both for the storage node and for the format node
and format them in the test case.
Reviewed-by: NEric Blake <eblake@redhat.com>

Remove the complex and unreliable code which inferred the node name
hierarchy only from data returned by 'query-named-block-nodes'. It turns
out that query-blockstats contain the full hierarchy of nodes as
perceived by qemu so the inference code is not necessary.

In query blockstats, the 'parent' object corresponds to the storage
behind a storage volume and 'backing' corresponds to the lower level of
backing chain. Since all have node names this data can be really easily
used to detect node names.

In addition to the code refactoring the one remaining test case needed
to be fixed along.
Reviewed-by: NEric Blake <eblake@redhat.com>

Make it less confusing by naming the field which refers to the storage
object as 'nodestorage'.
Reviewed-by: NEric Blake <eblake@redhat.com>

The same operation will become useful in other places so rename the
function to be more generic and move it to the top so that it can be
reused earlier in the file.
Reviewed-by: NEric Blake <eblake@redhat.com>

Currently, @port is type of string. Well, that's overkill and
waste of memory. Port is always an integer. Use it as such.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Recent refactors made it so that the function may use uninitialized
pointer, but it actually wanted to use a different variable and value
at all.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

New name is qemuBlockStorageSourceGetGlusterProps and also hardcode the
protocol name rather than calling the ToString function, since this
function can't be made universal.

New name is qemuBlockStorageSourceBuildHostsJSONSocketAddress since it
formats the JSON object in accordance with qemu's SocketAddress type.

Since the new naming in qemu uses 'inet' instead of 'tcp' add a
compatibility layer for gluster which uses the old name.

Rename it to qemuBlockStorageSourceGetBackendProps and refactor it to
return the JSON object instead of filling a pointer since now it's
always expected to return data.

Pure code movement except for the tweaks necessary for cross-usage.

Becase it can be called during migration out (namely on cancelling
blockjobs).
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

To allow updating stats based on the node name, add a helper function
that will fetch the required data from 'query-named-block-nodes' and
return it in hash table for easy lookup.

Detect the node names when setting block threshold and when reconnecting
or when they are cleared when a block job finishes. This operation will
become a no-op once we fully support node names.

qemu for some time already sets node names automatically for the block
nodes. This patch adds code that attempts a best-effort detection of the
node names for the backing chain from the output of
'query-named-block-nodes'. The only drawback is that the data provided
by qemu needs to be matched by the filename as seen by qemu and thus
if two disks share a single backing store file the detection won't work.

This will allow us to use qemu commands such as
'block-set-write-threshold' which only accepts node names.

In this patch only the detection code is added, it will be used later.