Pass backing store as an argument rather than extracting it locally and
fix the callers.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Pass in backing store explicitly to qemuBlockStorageSourceGetBlockdevProps
and fix the callers.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
QEMU finally exposes an interface which allows us to instruct it to
format or create arbitrary images. This is required for blockdev
integration of block copy and snapshots as we need to pre-format images
prior to use with blockdev-add.
This path introduces job handling and also helpers for formatting and
attaching a whole image described by a virStorageSource.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In case when the backing store can be represented with something
simpler such as a URI we can use it rather than falling back to the
json: pseudo-protocol.
In cases when it's not worth it (e.g. with the old ugly NBD or RBD
strings) let's switch to json.
The function is exported as we'll need it when overwriting the ugly
strings qemu would come up with during blockjobs.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
For the modern use cases we are going to use 'blockdev-snapshot' instead
of 'blockdev-snapshot-sync'.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
QEMU allows us to create storage on certain network protocols which
allow image creation through their API. Wire up the generator for using
it with libvirt as well as for local files.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
'blockdev-add' allows us to use qemu to format images to our desired
format. This patch implements helpers which convert a
virStorageSourcePtr into JSON objects describing the required
configuration.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
To allow using -blockdev with blockjobs QEMU needs to reopen files in
read-write mode when modifying the backing chain. To achieve this we
need to use 'auto-read-only' for the backing files rather than the
normal 'read-only' property. That way qemu knows that the files need to
be reopened.
Note that the format drivers (e.g. qcow2) are still opened with the
read-only property enabled when being a member of the backing chain
since they are supposed to be immutable unless a block job is started.
QEMU v4.0 (since commit 23dece19da4) allows also dynamic behaviour for
auto-read-only which allows us to use sVirt as we only grant write
permissions to files when doing a blockjob.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When formatting new qcow2 images we need to provide the backing store
string which should not contain any authentication or irrelevant data.
Add a flag for qemuBlockStorageSourceGetBackendProps which allows to
skip the irrelevant data.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
These are meant to replace the ad-hoc helpers qemuHotplugDiskSourceAttach...
and the open-coded version in qemu_command.c for use in command line
generation.
The functions for preparing for attach of chains unfortunately need to
be in qemu_command.c as they use function defined by that file and
inclusion hierarchy.
In this patch new functions are introduced and subsequent patches then
refactor individual parts to use them.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Move it to qemu_block.c and call it qemuBlockStorageSourceDetachPrepare.
It will be reused in other parts as well.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján 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: Daniel 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: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján 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: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján 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: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján 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: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján 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: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John 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: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John 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: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John 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.
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: Eric 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.
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.
