'file' is too generic to know what's going on. Rename it to
'memorysnapshotfile'.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Use the snapshot disk type from the definition now that we validate that
it matches.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The code executed later when creating a snapshot makes all decisions
based on the configured type rather than the actual type of the existing
file, while the check whether the file exists is based solely on the
on-disk type.
Since a block device is allowed to exist even when not reusing existing
files in contrast to regular files this creates a potential for a block
device to squeak past the check but then be influenced by other code
executed later. Specifically this is a problem when creating a snapshot
with the following XML:
<domainsnapshot>
<disks>
<disk name='vdb' type='file'>
<source file='/dev/sdb'/>
</disk>
</disks>
</domainsnapshot>
If the snapshot creation fails, '/dev/sdb' will be removed because it's
considered to be a regular file by the cleanup code.
Add a check that will force that the configured type matches the on-disk
state.
Additional supporting reason is that qemu stopped to accept block
devices with the 'file' backend, thus the above configuration will not
work any more. This allows us to fail sooner.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1972145
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In case when the snapshot target is of VIR_STORAGE_TYPE_BLOCK type and
doesn't exist libvirt won't be able to create it. Reject such a config
sooner.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Separate the 'else if' branches into nested conditions so that it's more
obvious when we'll be adding additional checks later.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Later patches will implement sharing of the backing file, so we'll need
to be able to discriminate the overlays per VM.
Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The code deals with the startup of the VM and just uses the snapshot
code to achieve the desired outcome.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
We store the virQEMUDriverConfig object in the context.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Remove all the arguments which are present in qemuSnapshotDiskContext.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The config is used both with the preparation and execution functions, so
we can store it in the context to simplify other helpers.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Rather than filling various parts of the context from arguments pass in
the whole context.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The code will be later reused when adding support for sharing the
backing image of the snapshot.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Historically, we declared pointer type to our types:
typedef struct _virXXX virXXX;
typedef virXXX *virXXXPtr;
But usefulness of such declaration is questionable, at best.
Unfortunately, we can't drop every such declaration - we have to
carry some over, because they are part of public API (e.g.
virDomainPtr). But for internal types - we can do drop them and
use what every other C project uses 'virXXX *'.
This change was generated by a very ugly shell script that
generated sed script which was then called over each file in the
repository. For the shell script refer to the cover letter:
https://listman.redhat.com/archives/libvir-list/2021-March/msg00537.html
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
The -2 value is misleading because if 'qemuAgentFSFreeze' fails it
doesn't necessarily mean that the command was sent to the agent.
Since callers don't care about the -2 value specifically, remove it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
If we didn't freeze any filesystems we should not even attempt thawing
them. Additionally 'guest-fsfreeze-freeze' fails if the filesystems are
already frozen, where thawing them may break users data integrity if
they used VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE accidentally after an
explicit virDomainFSFreeze and the next snapshot without that flag would
be taken with already thawed filesystems.
This effectively reverts 7c736bab06 .
Libvirt nowadays checks whether the guest agent is connected and pings
it before issuing an command so it's very unlikely that we'd end up in a
situation where qemuSnapshotCreateActiveExternal froze filesystems and
didn't thaw them.
Additionally we now discourage the use of
VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE since users have better control if
they freeze the FS themselves.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Rename the function to virStorageSourceFetchRelativeBackingPath and
return relative paths only. The function is only used to restore the
relative relationship between images so there's no need for it to be
universal.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Up until now we had a runtime code and XML related code in the same
source file inside util directory.
This patch takes the runtime part and extracts it into the new
storage_file directory.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
These files are using functions from virstoragefile.h but are missing
explicit include.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
qemu's qcow2 driver allows control of the metadata cache of qcow2 driver
by the 'cache-size' property. Wire it up to the recently introduced
elements.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Whether a snapshot definition is considered 'current' or active is
stored in the metadata XML libvirt writes when we create metadata.
This means that if we are changing the 'current' snapshot we must
re-write the metadata of the previously 'current' snapshot to update the
field to prevent having multiple active snapshots.
Unfortunately the snapshot creation code didn't do this properly, which
resulted in the following error:
error : qemuDomainSnapshotLoad:430 : internal error: Too many snapshots claiming to be current for domain snapshot-test
being printed if libvirtd was terminated and restarted.
Introduce qemuSnapshotSetCurrent which writes out the old snapshot's
metadata when updating the current snapshot.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In some cases such as when creating an internal inactive snapshot we
know that the domain definition in the snapshot is equivalent to the
current definition. Additionally we set up the current definition for
the snapshotting but not the one contained in the snapshot. Thus in some
cases the caller knows better which def to use.
Make qemuDomainSnapshotForEachQcow2 take the definition by the caller
and copy the logic for selecting the definition to callers where we
don't know for sure that the above claim applies.
This fixes internal inactive snapshots when <disk type='volume'> is used
as we translate the pool/vol combo only in the current def.
Resolves: https://gitlab.com/libvirt/libvirt/-/issues/97
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
If domain name is changed since snapshot we need to update it to current in
config taken from snapshot.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Don't hide our use of GHashTable behind our typedef. This will also
promote the use of glibs hash function directly.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Matt Coleman <matt@datto.com>
All users of virHashTable pass strings as the name/key of the entry.
Make this an official requirement by turning the variables to 'const
char *'.
For any other case it's better to use glib's GHashTable.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
To implement <transient/> disks we'll need to install an overlay on top
of the original disk image which will be discarded after the VM is
turned off. This was initially implemented by qemu but libvirt never
picked up this option as the overlays were created by qemu without
libvirt involvment which didn't work with SELinux.
With blockdev the qemu feature became unsupported so we need to do this
via the snapshot code anyways.
The helpers introduced in this patch prepare a fake snapshot disk
definition for a disk which is configured as <transient/> and use it to
create a snapshot (without actually modifying metadata or persistent
def).
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Tested-by: Ján Tomko <jtomko@redhat.com>
'ndd' tracks the actual number of snapshot disks filled into the
structure and is incremented by the functions filling the context, thus
it must not be set when initializing the context.
Fixes: 8c2ecdf131
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The container itself needs to be freed too.
Fixes: 8c2ecdf131
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Make it obvious that the snapshot is prepared for the active external
snapshot case.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extract the code which invokes the monitor and finalizes the snapshot
into a separate function for easier reuse.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Add a container struct which holds all data needed to create and clean
up after a (for now external) snapshot. This will aggregate all the
'qemuSnapshotDiskDataPtr' the 'actions' of a transaction QMP command and
everything needed for cleanup at any given point.
This aggregation allows to simplify the arguments of the functions which
prepare the snapshot data and additionally will simplify the code
necessary for creating overlays on top of <transient/> disks.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Be more specific about the role of the function. It's creating the disk
portion of an external active snapshot.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
After virDomainSnapshotAlignDisks is called the definitions of disks in
the snapshot definition and in the domain definition are in the same
order so they can be addressed using the same index.
This frees up 'idx' to be removed later.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Add an abort() on the class/object allocation failures so that
virStorageSourceNew() always returns a virStorageSource and remove
checks from all callers.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This patch is just revert of [1]. Actually we should NOT pass
QEMU_ASYNC_JOB_NONE as that patch suggests while we are in async job in order
to acquire nested jobs correctly. The patch tries to fix issues introduced by
another patch [2] where jobs are mistakenly cleared out in qemuProcessStop.
Later patch [3] fixed the issue introduced by patch [2]. Now we need to revert
[1] as well as we now still have same concurrency crash issues as [3] described
but for the force revert.
[1] 0c4408c83: qemu: Don't use asyncJob after stop during snapshot revert
[2] 888aa4b6b: qemuDomainObjPrivateDataClear: Don't leak @migParams
[3] d75f865fb: qemu: fix concurrency crash bug in snapshot revert
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
We've dumped all the snapshot helpers and related code into
qemu_driver.c. It accounted for ~10% of overal size of qemu_driver.c.
Separate the code to qemu_snapshot.c/h.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>