Commit Graph

14 Commits

Author SHA1 Message Date
Pavel Hrdina
09c12ba248 qemu_dbus: use emulator cgroup for dbus-daemon
All other helper processes are moved to cgroup with QEMU emulator
thread as we keep the root VM cgroup without any processes. This
assumption is validated in qemuRestoreCgroupState() which is called
when libvirtd is restarted and reconnected to all running VMs.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-11-03 21:26:32 +01:00
Pavel Hrdina
b43acd8e82 qemu: remove dead code that setup cgroups for helper processes
In both cases priv->cgroup will always be NULL because it is called
before the QEMU process is started and cgroups are configured.

In qemuProcessLaunch() the call order is following:

    qemuExtDevicesStart()
    ...
    virCommandRun()
    ...
    qemuSetupCgroup()

where qemuDBusStart() is called from qemuExtDevicesStart() but we
cgroups are created in qemuSetupCgroup().

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-11-03 21:26:32 +01:00
Bihong Yu
3ee423c363 qemu: pre-create the dbus directory in qemuStateInitialize
There are races condiction to make '/run/libvirt/qemu/dbus' directory in
virDirCreateNoFork() while concurrent start VMs, and get "failed to create
directory '/run/libvirt/qemu/dbus': File exists" error message. pre-create the
dbus directory in qemuStateInitialize.

Signed-off-by: Bihong Yu <yubihong@huawei.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2020-07-22 09:40:15 +02:00
Laine Stump
b8b58e22b9 qemu: use g_auto() for all virBuffers
Signed-off-by: Laine Stump <laine@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-07-08 16:34:02 -04:00
Marc-André Lureau
8e1ac0d384 qemu-dbus: register DBus bus to the VM cgroup
External devices are started before cgroup is created. Add the DBus
daemon to the VM cgroup with the rest of the external devices.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-04-22 09:58:10 +02:00
Marc-André Lureau
5f56cb8bc8 qemu-dbus: remove unused variable
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-04-22 09:58:10 +02:00
Marc-André Lureau
a86094d694 qemu-dbus: prevent double start of the bus daemon
Allow calling qemuDBusStart() multiple times (as may be done by
qemu-slirp already).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-04-22 09:58:10 +02:00
Marc-André Lureau
6077ae7b40 qemu: add dbus-vmstate helper migration support
Helper processes may have their state migrated with QEMU data stream
thanks to the QEMU "dbus-vmstate".

libvirt maintains the list of helpers to be migrated. The
"dbus-vmstate" is added when required, and given the list of helper
Ids that must be migrated, on save & load sides.

See also:
https://git.qemu.org/?p=qemu.git;a=blob;f=docs/interop/dbus-vmstate.rst

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>
2020-03-24 15:57:33 +01:00
Marc-André Lureau
8ef82dec5c qemu: add a DBus daemon helper unit
Add a unit to start & stop a private dbus-daemon.

The daemon is meant to be started on demand, and associated with a
QEMU process. It should be stopped when the QEMU process is stopped.

The current policy is permissive like a session bus. Stricter
policies can be added later, following recommendations from:
https://git.qemu.org/?p=qemu.git;a=blob;f=docs/interop/dbus.rst

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>
2020-03-24 15:57:33 +01:00
Marc-André Lureau
62f696c333 qemu: remove dbus-vmstate code
This code was based on a per-helper instance and peer-to-peer
connections. The code that landed in qemu master for v5.0 is relying
on a single instance and DBus bus.

Instead of trying to adapt the existing dbus-vmstate code, let's
remove it and resubmit. That should make reviewing easier.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-03-24 15:57:33 +01:00
Ján Tomko
ce36e33c10 qemu: use g_strdup instead of VIR_STRDUP
Replace all occurrences of
  if (VIR_STRDUP(a, b) < 0)
     /* effectively dead code */
with:
  a = g_strdup(b);

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-21 12:51:57 +02:00
Ján Tomko
483a14f871 Remove all usage of VIR_RETURN_PTR
Prefer:
    return g_steal_pointer(&ptr);

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-16 15:59:41 +02:00
Ján Tomko
45678bd70a Use g_autoptr instead of VIR_AUTOPTR
Since commit 44e7f02915
    util: rewrite auto cleanup macros to use glib's equivalent

VIR_AUTOPTR aliases to g_autoptr. Replace all of its use by the GLib
macro version.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-10-16 12:06:43 +02:00
Marc-André Lureau
2b0251af68 qemu: add dbus-vmstate
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>
2019-09-06 12:47:47 +02:00