The only reason we need it at build time is to find its location in
$PATH so it can be hardcoded into the libvirt binary (and avoid the
possibility of someone adding in a malicious binary somewhere earlier
in the path, I guess).
Only 'recommend' passt during installation though, since it is not
needed unless someone is actually using it.
There is no need to add in a build-time "WITH_PASST" option (IMO),
since it adds very little to the size of the code - "PASST" (the path
to the binary) will just be set to "passt", so if someone does manage
to build and install passt on an older version of Fedora or RHEL, it
will still work (as long as it's installed somewhere in the path).
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This consists of (1) adding the necessary args to the qemu commandline
netdev option, and (2) starting a passt process prior to starting
qemu, and making sure that it is terminated when it's no longer
needed. Under normal circumstances, passt will terminate itself as
soon as qemu closes its socket, but in case of some error where qemu
is never started, or fails to startup completely, we need to terminate
passt manually.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
passt support requires "-netdev stream", which was added to QEMU in
qemu-7.2.0.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This implements XML config to represent a subset of the features
supported by 'passt' (https://passt.top), which is an alternative
backend for emulated network devices that requires no elevated
privileges (similar to slirp, but "better").
Along with setting the backend to use passt (via <backend
type='passt'/> when the interface type='user'), we also support
passt's --log-file and --interface options (via the <backend>
subelement logFile and upstream attributes) and its --tcp-ports and
--udp-ports options (which selectively forward incoming connections to
the host on to the guest) via the new <portForward> subelement of
<interface>. Here is an example of the config for a network interface
that uses passt to connect:
<interface type='user'>
<mac address='52:54:00:a8:33:fc'/>
<ip address='192.168.221.122' family='ipv4'/>
<model type='virtio'/>
<backend type='passt' logFile='/tmp/xyzzy.log' upstream='eth0'/>
<portForward address='10.0.0.1' proto='tcp' dev='eth0'>
<range start='2022' to='22'/>
<range start='5000' end='5099' to='1000'/>
<range start='5010' end='5029' exclude='yes'/>
</portForward>
<portForward proto='udp'>
<range start='10101'/>
</portForward>
</interface>
In this case:
* the guest will be offered address 192.168.221.122 for its interface
via DHCP
* the passt process will write all log messages to /tmp/xyzzy.log
* routes to the outside for the guest will be derived from the
addresses and routes associated with the host interface "eth0".
* incoming tcp port 2022 to the host will be forwarded to port 22
on the guest.
* incoming tcp ports 5000-5099 (with the exception of ports 5010-5029)
to the host will be forwarded to port 1000-1099 on the guest.
* incoming udp packets on port 10101 will be forwarded (unchanged) to
the guest.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Initial support for network devices using passt (https://passt.top)
for the backend connection will require:
* new attributes of the <backend> subelement:
* "type" that can have the value "passt" (to differentiate from
slirp, because both slirp and passt will use <interface
type='user'>)
* "logFile" (a path to a file that passt should use for its logging)
* "upstream" (a netdev name, e.g. "eth0").
* a new subelement <portForward> (described in more detail later)
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This will allow us to call parser/formatter functions with a pointer
to just the backend part.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This fits better with the element containing the value (<driver>), and
allows us to use virDomainNetBackend* for things in the <backend>
element.
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Enable the qemuxml2xml variant and add output data for qemuxml2argvtest.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Assert support for VIR_DOMAIN_DEF_FEATURE_DISK_FD in the qemu driver
now that all code paths are adapted.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Probing stats and block copy to a FD passed image is not yet supported.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
We assume that FD passed images already exist so all existance checks
are skipped.
For the case that a FD-passed image is passed without a terminated
backing chain (thus forcing us to detect) we attempt to read the header
from the FD.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Unfortunately unlike with DAC we can't simply ignore labelling for the
FD and it also influences the on-disk state.
Thus we need to relabel the FD and we also store the existing label in
cases when the user will request best-effort label replacement.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
DAC security label is irrelevant once you have the FD. Disable all
labelling for such images.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Prepare the internal data for passing FDs instead of having qemu open
the file internally.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
When starting up a VM with FD-passed images we need to look up the
corresponding named FD set and associate it with the virStorageSource
based on the name.
The association is brought into virStorageSource as security labelling
code will need to access the FD to perform selinux labelling.
Similarly when startup is complete in certain cases we no longer need to
keep the copy of FDs and thus can close them.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The helper will be used in various places that need to check that a disk
source struct is using FD passing.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The new helper qemuDomainStartupCleanup is used to perform cleanup after
a startup of a VM (successful or not). The initial implementation just
calls qemuDomainSecretDestroy, which can be un-exported.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The 'fdgroup' will allow users to specify a passed FD (via the
'virDomainFDAssociate()' API) to be used instead of opening a path.
This is useful in cases when e.g. the file is not accessible from inside
a container.
Since this uses the same disk type as when we open files via names this
patch also introduces a hypervisor feature which the hypervisor asserts
that code paths are ready for this possibility.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Introduce a new argument type for testQemuInfoSetArgs named ARG_FD_GROUP
which allows users to instantiate tests with populated FD passing hash
table.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Implement passing and storage of FDs for the qemu driver. The FD tuples
are g_object instances stored in a per-domain hash table and are
automatically removed once the connection is closed.
In the future we can consider supporting also to not tie the lifetime of
the passed FDs bound to the connection.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
For FD-passing of disk sources we'll need to keep the FDs around.
Introduce a data type helper based on a g_object so that we get
reference counting.
One instance will (due to security labelling) will need to be part of
the virStorageSource struct thus it's declared in the storage_source_conf
module.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The API can be used to associate one or more (e.g. a RO and RW fd for a
disk backend image) FDs to a VM. They can be then used per definition.
The primary use case for now is for complex deployment where
libvirtd/virtqemud may be run inside a container and getting the image
into the container is complicated.
In the future it will also allow passing e.g. vhost FDs and other
resources to a VM without the need to have a filesystem representation
for it.
Passing raw FDs has few intricacies and thus libvirt will by default not
restore security labels.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The patch moving the code didn't faithfully represent the typecasting
of the 'bandwidth' variable needed to properly convert from the legacy
'unsigned long' argument which resulted in a build failure on 32 bit
systems:
../src/qemu/qemu_block.c: In function ‘qemuBlockCommit’:
../src/qemu/qemu_block.c:3249:23: error: comparison is always false due to limited range of data type [-Werror=type-limits]
3249 | if (bandwidth > LLONG_MAX >> 20) {
| ^
Fix it by returning the check into qemuDomainBlockCommit as it's needed
only because of the legacy argument type in the old API and use
'unsigned long long' for qemuBlockCommit.
Fixes: f5a77198bf
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Some compilers aren't happy when an automatically freed variable is used
just to free something (thus it's only assigned in the code):
When compiling qemuSnapshotDelete after recent commits they complain:
../src/qemu/qemu_snapshot.c:3153:61: error: variable 'delData' set but not used [-Werror,-Wunused-but-set-variable]
g_autoslist(qemuSnapshotDeleteExternalData) delData = NULL;
^
To work around the issue we can restructure the code which also has the
following semantic implications:
- since qemuSnapshotDeleteExternalPrepare does validation we error out
sooner than attempting to start the VM
- we read the temporary variable at least in one code path
Fixes: 4a4d89a925
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Use a temporary variable to avoid memory alignment issues on ARM:
../src/nwfilter/nwfilter_dhcpsnoop.c: In function ‘virNWFilterSnoopLeaseFileLoad’:
../src/nwfilter/nwfilter_dhcpsnoop.c:1745:20: error: cast increases required alignment of target type [-Werror=cast-align]
1745 | (unsigned long long *) &ipl.timeout,
|
Fixes: 0d278aa089
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Now that deletion of external snapshot is implemented document the
current virDomainSnapshotDelete supported state.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
If the daemon crashes or is restarted while the snapshot delete is in
progress we have to handle it gracefully to not leave any block jobs
active.
For now we will simply abort the snapshot delete operation so user can
start it again. We need to refuse deleting external snapshots if there
is already another active job as we would have to figure out which jobs
we can abort.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
When daemon is restarted and libvirt tries to recover domain jobs we
need to know if the snapshot job was a snapshot delete in order to
safely abort running QEMU block jobs.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
When deleting external snapshots the operation may fail at any point
which could lead to situation that some disks finished the block commit
operation but for some disks it failed and the libvirt job ends.
In order to make sure that the qcow2 images are in consistent state
introduce new element "<snapshotDeleteInProgress/>" that will mark the
disk in snapshot metadata as invalid until the snapshot delete is
completed successfully.
This will prevent deleting snapshot with the invalid disk and in future
reverting to snapshot with the invalid disk.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
With external snapshots we need to modify the metadata bit more then
what is required for internal snapshots. Mainly the storage source
location changes with every external snapshot.
This means that if we delete non-leaf snapshot we need to update all
children snapshots and modify the disk sources for all affected disks.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
When deleting snapshot we are starting block-commit job over all disks
that are part of the snapshot.
This operation may fail as it writes data changes to the backing qcow2
image so we need to wait for all the disks to finish the operation and
wait for correct signal from QEMU. If deleting active snapshot we will
get `ready` signal and for inactive snapshots we need to disable
autofinalize in order to get `pending` signal.
At this point if commit for any disk fails for some reason and we abort
the VM is still in consistent state and user can fix the reason why the
deletion failed.
After that we do `pivot` or `finalize` if it's active snapshot or not to
finish the block job. It still may fail but there is nothing else we can
do about it.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
In order to save some CPU cycles we will collect all the necessary data
to delete external snapshot before we even start. They will be later
used by code that deletes the snapshots and updates metadata when
needed.
With external snapshots we need data that libvirt gets from running QEMU
process so if the VM is not running we need to start paused QEMU process
for the snapshot deletion and kill at afterwards.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Deleting external snapshots will require to run it as async domain job,
the same way as we do for snapshot creation.
For internal snapshots modify the job mask in order to forbid any other
job to be started.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Deleting internal snapshot when the currently active disk image is
different than where the internal snapshot was taken doesn't work
correctly.
This applies to a running VM only as we are using QMP command and
talking to the QEMU process that is using different disk.
This works correctly when the VM is shut of as in this case we spawn
qemu-img process to delete the snapshot.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Prepare the validation function for external snapshot delete support.
There is one exception when deleting `children-only` snapshots. If the
snapshot tree is like this example:
snap1 (external)
|
+- snap2 (internal)
|
+- snap3 (internal)
|
+- snap4 (internal)
and user calls `snapshot-delete snap1 --children-only` the current
snapshot is external but all the children snapshots are internal only
and we are able to delete it.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Extract the code deleting external snapshot metadata to separate
function.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Previously the reparent happened before the actual snapshot deletion.
This change moves the code closer to the rest of the code handling
snapshot metadata when deletion happens. This makes the metadate
deletion happen after the data files are deleted.
Following patch will extract it into separate function
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
This simplifies the code a bit by reusing existing parts that deletes
a single snapshot.
The drawback of this change is that we will now call the re-parent bits
to keep the metadata in sync for every child even though it will get
deleted as well.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Extract code that deletes children of specific snapshot to separate
function.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Extract code that deletes single snapshot to separate function.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
