Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Require that all headers are guarded by a symbol named

  LIBVIRT_$FILENAME

where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.

Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The copy on read functionality is done using a separate layer in the
backing chain. Add function to generate properties for it.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

With 'transaction' support we don't need to keep around the multipurpose
code which would create the snapshot if 'transaction' is not supported.

To simplify this add a new helper that just wraps the arguments for
'blockdev-snapshot-sync' operation in 'transaction' and use it instead
of qemuBlockSnapshotAddLegacy.

Additionally this allows to format the arguments prior to creating the
file for simpler cleanup.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Introduce a new setup function for all the related configuration and
move the setup and attachment of the PR code.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Create a new "Prepare" function and move the drive add code into the new
helpers. This will eventually allow to simplify and unify the attaching
code for use with blockdev at the same time as providing compatibility
with older qemus.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

These helpers add infrastructure which simplifies adding and rolling
back virStorageSources to a running qemu instance. Using of the helper
structure and separate functions allows for a much cleaner code in the
section dealing with the monitor.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

When using blockdev-add and friends, libvirt will need to create also
properties for the qcow2/raw/... format handler in qemu. This patch adds
the infrastructure and implements all formats known to libvirt including
all properties which are expressed at the format level in qemu.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

The gluster protocol in qemu uses two styles, one of which is legacy and
not covered by the QAPI schema.

To allow using of the new style in the blockdev-add code, add a
parameter for qemuBlockStorageSourceGetBackendProps which will switch
between the two modes.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

Storage source format backing a shared device (e.g. running a cluster
filesystem) needs to support the sharing so that metadata are not
corrupted. Add a central function for checking this.

Extract the part formatting the basic URI part so that it can be reused
to format JSON backing definitions. Parts specific to the command line
format will remain in qemuBuildNetworkDriveURI. The new function is
called qemuBlockStorageSourceGetURI.

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>

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.