This is an issue for LXC loop devices when you are trying to get loop
devices info using `ioctl`. Modern apps uses `/sys/dev/block` to grab
information about devices, but if you use the method mention you won't
be able to retrive the associated file with that loop device. See
example below from cryptsetup sources:
static char *_ioctl_backing_file(const char *loop)
{
struct loop_info64 lo64 = {0};
int loop_fd;
loop_fd = open(loop, O_RDONLY);
if (loop_fd < 0)
return NULL;
if (ioctl(loop_fd, LOOP_GET_STATUS64, &lo64) < 0) {
close(loop_fd);
return NULL;
}
lo64.lo_file_name[LO_NAME_SIZE-2] = '*';
lo64.lo_file_name[LO_NAME_SIZE-1] = 0;
close(loop_fd);
return strdup((char*)lo64.lo_file_name);
}
It will return an empty string because lo_file_name was not set.
Function `virFileLoopDeviceOpenSearch()` is using `ioctl` to query data,
but it is not checking `lo_file_name` field.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
When the network interface is of "user" type, and QEMU has the "-net
socket,fd=" datagram support, call qemuInterfacePrepareSlirp() to
probe and associate a slirp-helper with the interface.
The usage of automated slirp-helper can be prevented with
disableSlirp (in particular when resuming a
VM that didn't start with slirp-helper before).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
If a slirp-helper is associated with a network interface (after
probing & preparing succesfully), pass the socket fd to QEMU and use
"-net socket,fd=".
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
If a slirp-helper is associated with a network interface,
prepare/start/stop the process via qemu-extdevice.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
For VM started and migrated/saved without slirp-helpers, let's prevent
the automatic setup (as it would fail to migrate otherwise).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Save & restore the slirp helper PID associated with a network
interface & the probed features.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
The unit provides the functions associated with a slirp-helper:
- probing / checking capabilities
- opening the socketpair
- starting / stoping the helper
- registering for dbus-vmstate migration
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
A slirp helper is a process that provides user-mode networking through
a unix domain socket. It is expected to follow the following
specification:
https://gitlab.freedesktop.org/slirp/libslirp-rs/blob/master/src/bin/README.rst
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Add dbusVMStates to keep a list of dbus-vmstate objects needed for
migration. They are populated on the command line during start or
qemuDBusVMStateAdd/Remove() will hotplug them as needed.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Add a generic way to run a command through the security management.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
pid filenames (from swtpm and other helpers from this series) are
based on VM shortname, which is derived from VM id. If the id is reset
to early, the state filenames will not be found.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This object is being proposed to qemu upstream "Add dbus-vmstate
object". It handles data migration of external processes.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Datagram socket is available since qemu 4.0, commit
fdec16e3c2a614e2861f3086b05d444b5d8c3406 ("net/socket: learn to talk
with a unix dgram socket").
Required for slirp-helper communication.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Once QEMU is started, the qemuDomainLogContext is owned by it, and can
no longer be used from libvirt. Instead, use
qemuDomainLogAppendMessage() which will redirect the log.
This is not strictly necessary for swtpm, but the following patches
are going to reuse qemuExtDeviceLogCommand().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
dbus_message_new() does not construct correct replies by itself, it is
recommended to use dbus_message_new_method_return() instead.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
It is failing, because it ends up being parsed with version='default'
and expects '1.2' instead.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Implicitly the query depth is limited by the length of the QAPI schema
query, but 'alternate' and 'array' QAPI meta-types don't consume a part
of the query string thus a loop on such types would get our traversal
code stuck in an infinite loop. Prevent this from happening by limiting
the nesting depth to 1000.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
After parsing a video device with a model type of
VIR_DOMAIN_VIDEO_TYPE_NONE, all device info is cleared (see
virDomainDefPostParseVideo()) in order to avoid formatting any
auto-generated values for the XML. Subsequently, however, an alias is
generated for the video device (e.g. 'video0'), which results in an
alias property being formatted in the XML output anyway. This creates
confusion if the user has explicitly provided an alias for the video
device since the alias will change.
To avoid this, don't clear the user-defined alias for video devices of
type "none".
https://bugzilla.redhat.com/show_bug.cgi?id=1720612
Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
When we set cpu.max period we need to parse the cpu.max file first as
it contains both quota and period values separated by space. When only
a single number is written to that file it will set quota. However,
in order to change period we need to write both values.
The code was prepared for that but mistakenly used new line to end the
string with the first value.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1749227
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
When blockdev is used we always should use the blockdev mode for
non-shared storage migration.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Remove libvirt's support check for the target of an external snapshot to
the blockdev code or qemu. This will potentially require a more complex
cleanup but removes a level of hardcoded feature checks.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Use the code for creating or attaching new storage source in the
snapshot code and switch to 'blockdev-snapshot' for creating the
snapshot itself.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
With blockdev we'll be able to support protocols which are not supported
by the storage backends in libvirt. This means that we have to be able
to skip the creation and relative storage path reading if it's not
supported. This will make it impossible to use relative backing for
network protocols but that would be almost insane anyways.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
After we always assume support for the 'transaction' command
(c358adc571) and follow-up cleanups
qemuDomainSnapshotCreateSingleDiskActive lost its value. Move the code
into appropriate helpers and remove the function.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Fix and unify the naming of external snapshot preparation functions.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Make qemuDomainSnapshotDiskDataCleanup cleanup section friendly by
moving the error preservation code inside it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We changed to always saving the status and config XMLs to simplify
code. After a few more refactors it's now possible to move it to the
appropriate place and save the XMLs only on success again.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When we take a snapshot we must properly remove our locking
infrastructure locks. This was broken by commit 3817fa10c4 which
attempted to properly track the readonly state for the image as the
locking code was executed after this change. Since we forced the image
which was locked as read-write to read-only prior to unlocking it the
write lock was not dropped.
Fix it by moving the locking code prior to modifying the readonly flag.
https://bugzilla.redhat.com/show_bug.cgi?id=1745618
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The code preparing data for creating/attaching the target image of block
copy didn't use the correct reference to the existing backing chain in
case when the copy should inherit it. This meant that qemu actually
opened a second copy of the chain and operated on that.
This would de-sync qemu from libvirt's view of node names. Luckily this
is only hypothetical at this point since it happens only when -blockdev
is enabled.
Fix it by passing 'mirrorBacking' which has the proper data as the
backing store when calling
qemuBuildStorageSourceChainAttachPrepareBlockdevTop.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In some cases we'll need to pass in a backing store which is not
recorded as the backing store of @src. Export backingStore as variable
and fix all callers to pass in the backing store. No semantic changes
for now.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
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>
Extract the loop and supporting infrastructure to the caller as only one
of the two callers actually cares about looping and rename the helper to
qemuBuildStorageSourceChainAttachPrepareBlockdevOne.
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>
Move all bits of the formatting of the 'backing' attribute to a single
condition and make it use a single extracted copy of the backing store.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Since libvirt stores the backing chain into the XML in a nested way it
is the prime possibility to hit libxml2's parsing limit of 256 layers.
Introduce code which will crawl the backing chain and verify that it's
not too deep. The maximum nesting is set to 200 layers so that there's
still some space left for additional properties or nesting into snapshot
XMLs.
The check is applied to all disk use cases (starting, hotplug, media
change) as well as block copy which changes image and snapshots.
We simply report an error and refuse the operation.
Without this check a restart of libvirtd would result in the status XML
failing to be parsed and thus losing the VM.
https://bugzilla.redhat.com/show_bug.cgi?id=1524278
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
With blockdev we must issue the block_set_io_throttle QMP command to
setup disk throttling as we currently can't do it with the 'throttle'
layer.
Unfortunately there's nothing we can do if it fails.
https://bugzilla.redhat.com/show_bug.cgi?id=1733163
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
