So far, libvirt generates the following path for memory:
$memoryBackingDir/$id-$shortName/ram-nodeN
where $memoryBackingDir is the path where QEMU mmaps() memory for
the guest (e.g. /var/lib/libvirt/qemu/ram), $id is domain ID
and $shortName is shortened version of domain name. So for
instance, the generated path may look something like this:
/var/lib/libvirt/qemu/ram/1-QEMUGuest/ram-node0
While in case of embed driver the following path would be
generated by default:
$root/lib/qemu/ram/1-QEMUGuest/ram-node0
which is not clashing with other embed drivers, we allow users to
override the default and have all embed drivers use the same
prefix. This can create clashing paths. Fortunately, we can reuse
the approach for machined name generation
(v6.1.0-178-gc9bd08ee35) and include part of hash of the root in
the generated path.
Note, the important change is in qemuGetMemoryBackingBasePath().
The rest is needed to pass driver around.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
So far, libvirt generates the following path for hugepages:
$mnt/libvirt/qemu/$id-$shortName
where $mnt is the mount point of hugetlbfs corresponding to
hugepages of desired size (e.g. /dev/hugepages), $id is domain ID
and $shortName is shortened version of domain name. So for
instance, the generated path may look something like this:
/dev/hugepages/libvirt/qemu/1-QEMUGuest
But this won't work with embed driver really, because if there
are two instances of embed driver, and they both want to start a
domain with the same name and with hugepages, both drivers will
generate the same path which is not desired. Fortunately, we can
reuse the approach for machined name generation
(v6.1.0-178-gc9bd08ee35) and include part of hash of the root in
the generated path.
Note, the important change is in qemuGetBaseHugepagePath(). The
rest is needed to pass driver around.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
This reverts commit 06a19921b6.
What I haven't realized when writing this ^^ commit is that the
virQEMUDriver structure already stores the root directory path.
And since the pointer is immutable it can be accessed right from
the structure and thus there is no need to duplicate it in the
driver config.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Initially introduced in v3.10.0-rc1~172.
When generating a path for memory-backend-file or -mem-path, qemu
driver will use the following pattern:
$memoryBackingDir/libvirt/qemu/$id-$shortName
where $memoryBackingDir defaults to /var/lib/libvirt/qemu/ram but
can be overridden in qemu.conf. Anyway, the "/libvirt/qemu/" part
looks redundant, because it's already contained in the default,
or creates unnecessary nesting if overridden in qemu.conf.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Introduced in v1.2.17-rc1~121, the assumption was that the
driver->privileged is immutable at the time but it might change
in the future. Well, it did not ever since. It is still immutable
variable. Drop the needless accessor then.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
When initializing virQEMUDriverConfig structure we are given the
root directory for possible embed connection. Save it for future
use. While we could get it later from @uri member, it's not as
easy as dereferencing a pointer (virURIParse() +
virURIGetParam() + error reporting).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Add a 'virtiofsd_debug' option for tuning whether to run virtiofsd
in debug mode.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Tested-by: Andrea Bolognani <abologna@redhat.com>
This enables support for running QEMU embedded to the calling
application process using a URI:
qemu:///embed?root=/some/path
Note that it is important to keep the path reasonably short to
avoid risk of hitting the limit on UNIX socket path names
which is 108 characters.
When using the embedded mode with a root=/var/tmp/embed, the
driver will use the following paths:
logDir: /var/tmp/embed/log/qemu
swtpmLogDir: /var/tmp/embed/log/swtpm
configBaseDir: /var/tmp/embed/etc/qemu
stateDir: /var/tmp/embed/run/qemu
swtpmStateDir: /var/tmp/embed/run/swtpm
cacheDir: /var/tmp/embed/cache/qemu
libDir: /var/tmp/embed/lib/qemu
swtpmStorageDir: /var/tmp/embed/lib/swtpm
defaultTLSx509certdir: /var/tmp/embed/etc/pki/qemu
These are identical whether the embedded driver is privileged
or unprivileged.
This compares with the system instance which uses
logDir: /var/log/libvirt/qemu
swtpmLogDir: /var/log/swtpm/libvirt/qemu
configBaseDir: /etc/libvirt/qemu
stateDir: /run/libvirt/qemu
swtpmStateDir: /run/libvirt/qemu/swtpm
cacheDir: /var/cache/libvirt/qemu
libDir: /var/lib/libvirt/qemu
swtpmStorageDir: /var/lib/libvirt/swtpm
defaultTLSx509certdir: /etc/pki/qemu
At this time all features present in the QEMU driver are available when
running in embedded mode, availability matching whether the embedded
driver is privileged or unprivileged.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When QEMU uid/gid is set to non-root this is pointless as if we just
used a regular setuid/setgid call, the process will have all its
capabilities cleared anyway by the kernel.
When QEMU uid/gid is set to root, this is almost (always?) never
what people actually want. People make QEMU run as root in order
to access some privileged resource that libvirt doesn't support
yet and this often requires capabilities. As a result they have
to go find the qemu.conf param to turn this off. This is not
viable for libguestfs - they want to control everything via the
XML security label to request running as root regardless of the
qemu.conf settings for user/group.
Clearing capabilities was implemented originally because there
was a proposal in Fedora to change permissions such that root,
with no capabilities would not be able to compromise the system.
ie a locked down root account. This never went anywhere though,
and as a result clearing capabilities when running as root does
not really get us any security benefit AFAICT. The root user
can easily do something like create a cronjob, which will then
faithfully be run with full capabilities, trivially bypassing
the restriction we place.
IOW, our clearing of capabilities is both useless from a security
POV, and breaks valid use cases when people need to run as root.
This removes the clear_emulator_capabilities configuration
option from qemu.conf, and always runs QEMU with capabilities
when root. The behaviour when non-root is unchanged.
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Avoid grabbing the whole virCapsPtr object when we only need the
host CPU information.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Avoid grabbing the whole virCapsPtr object when we only need the
NUMA information.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Instead of using the virCapsPtr to get the default security model,
pass this in via the parser config.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
As part of a goal to eliminate the need to use virCapsPtr for anything
other than the virConnectGetCapabilies() API impl, cache the host arch
against the QEMU driver struct and use that field directly.
In the tests we move virArchFromHost() globally in testutils.c so that
every test runs with a fixed default architecture reported.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This previous commit introduced a simpler free callback for
hash data with only 1 arg, the value to free:
commit 49288fac96
Author: Peter Krempa <pkrempa@redhat.com>
Date: Wed Oct 9 15:26:37 2019 +0200
util: hash: Add possibility to use simpler data free function in virHash
It missed two functions in the hash table code which need
to call the alternate data free function, virHashRemoveEntry
and virHashRemoveSet.
After the previous patch though, there is no code that
makes functional use of the 2nd key arg in the data
free function. There is merely one log message that can
be dropped.
We can thus purge the current virHashDataFree callback
entirely, and rename virHashDataFreeSimple to replace
it.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Libvirt currently uses the VIR_AUTOUNREF macro for auto cleanup of
virObject instances. GLib approaches things differently with GObject,
reusing their g_autoptr() concept.
This introduces support for g_autoptr() with virObject, to facilitate
the conversion to GObject.
Only virObject classes which are currently used with VIR_AUTOREF are
updated. Any others should be converted to GObject before introducing
use of autocleanup.
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@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>
For now it's just a helper for building a qemu virDomainCapsPtr,
used in qemuConnectGetDomainCapabilities
Reviewed-by: Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
This is similar to the existing directory for snapshots; the domain
will save one xml file per checkpoint, for reloading on the next
libvirtd restart. Fortunately, since checkpoints mandate RNG
validation, we are assured that the checkpoint name will be usable as
a file name (no abuse of '../escape' as a checkpoint name, for
example).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Some VM configurations may result in a large number of threads created by
the associated qemu process which can exceed the system default limit. The
maximum number of threads allowed per process is controlled by the pids
cgroup controller and is set to 16k when creating VMs with systemd's
machined service. The maximum number of threads per process is recorded
in the pids.max file under the machine's pids controller cgroup hierarchy,
e.g.
$cgrp-mnt/pids/machine.slice/machine-qemu\\x2d1\\x2dtest.scope/pids.max
Maximum threads per process is controlled with the TasksMax property of
the systemd scope for the machine. This patch adds an option to qemu.conf
which can be used to override the maximum number of threads allowed per
qemu process. If the value of option is greater than zero, it will be set
in the TasksMax property of the machine's scope after creating the machine.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
When we allow multiple instances of the driver for the same user
account, using a separate root directory, we need to ensure mutual
exclusion. Use a pidfile to guarantee this.
In privileged libvirtd this ends up locking
/var/run/libvirt/qemu/driver.pid
In unprivileged libvirtd this ends up locking
/run/user/$UID/libvirt/qemu/run/driver.pid
NB, the latter can vary depending on $XDG_RUNTIME_DIR
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In cases when e.g. a new feature breaks upstream behaviour it's useful
to allow users to disable the new feature to verify the regression and
possibly use it as a workaround until a fix is available.
The new qemu.conf option named "capability_filters" allows to remove
qemu capabilities from the detected bitmap.
This patch introduces the configuration infrastructure to parse the
option and pass it around.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
qemu_conf.c deals with the configuration file. Better fit for the
structure and freeing function will be qemu_domain.c where the rest of
the namespace parsing/formatting stuff resides.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The data injected via the namespace may contain also other things than
commandline passthrough definitions. Rename it to make it more
universal.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Unused as of:
commit f136b83139
qemu: Rework setting process affinity
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Add an option that lets the user specify the secret
that unlocks the server TLS key.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Introduce a set of bool variables with the 'present' suffix
to track whether the value was actually specified.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Require that all headers are guarded by a symbol named
LIBVIRT_$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>
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.
In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.
With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to find the
author of a particular bit of code.
This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.
The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
For metadata locking we might need an extra fork() which given
latest attempts to do fewer fork()-s is suboptimal. Therefore,
there will be a qemu.conf knob to {en|dis}able this feature. But
since the feature is actually not metadata locking itself rather
than remembering of the original owner of the file this is named
as 'rememberOwner'. But patches for that feature are not even
posted yet so there is actually no qemu.conf entry in this patch
nor a way to enable this feature.
Even though this is effectively a dead code for now it is still
desired.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
This config option allows users to set and enable lock manager
for domain metadata. The lock manager is going to be used by
security drivers to serialize each other when changing a file
ownership or changing the SELinux label. The only supported lock
manager is 'lockd' for now.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The option is insecure and it has been long enough for users to migrate
their disk files to use explicit format. Drop the option and related
code.
The config parser still parses it and rejects statup if it's still
present in the config in enabled state.
The augeas lens is also kept so that users can disable it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extend qemu_conf with user and group for running the tpm-emulator
and add directories to the configuration for the locations of the
log, state, and socket of the tpm-emulator.
Also add these new directories to the QEMU Makefile.inc.am and
the RPM spec file libvirt.spec.in.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Just like we allow users overriding path to bridge-helper
detected at compile time we can allow them to override path to
qemu-pr-helper.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Host tcp4/tcp6 ports is a global resource thus we need to make
port accounting also global or we have issues described in [1] when
port allocator ranges of different instances are overlapped (which
is by default for qemu for example).
Let's have only one global port allocator object that take care
of the entire ports range (0 - 65535) and introduce port range object
for clients to specify desired auto allocation band.
[1] https://www.redhat.com/archives/libvir-list/2017-December/msg00600.html
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Rather than expecting callers to pass a virConnectPtr into the
virDomainDiskTranslateSourcePool() method, just acquire a connection
to the storage driver when needed.
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This reverts commit 038eb472a0.
On reflection adding defaults for arbitrary guest XML device config
settings to the qemu.conf is not a sustainable path. Removing the
support for rx/tx queue size so that it doesn't set a bad precedent.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In 2074ef6cd4 and c56cdf259 (and friends) we've added two
attributes to virtio NICs: rx_queue_size and tx_queue_size.
However, sysadmins might want to set these on per-host basis but
don't necessarily have an access to domain XML (e.g. because they
are generated by some other app). So let's expose them under
qemu.conf (the settings from domain XML still take precedence as
they are more specific ones).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
In some cases management application needs to allocate memory for
qemu upfront and then just let qemu use that. Since we don't want
to expose path for memory-backend-file anywhere in the domain
XML, we can generate predictable paths. In this case:
$memoryBackingDir/libvirt/qemu/$shortName/$alias
where $shortName is result of virDomainDefGetShortName().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
