VFIO is (except devices without a physical IOMMU or some mediated devices)
incompatible with discarding of RAM. The kernel will pin basically all VM
memory. Let's convert to ram_block_discard_disable(), which can now
fail, in contrast to qemu_balloon_inhibit().
Leave "x-balloon-allowed" named as it is for now.
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Tony Krowiak <akrowiak@linux.ibm.com>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Pierre Morel <pmorel@linux.ibm.com>
Cc: Eric Farman <farman@linux.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-4-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Devices may have component devices and buses.
Device realization may fail. Realization is recursive: a device's
realize() method realizes its components, and device_set_realized()
realizes its buses (which should in turn realize the devices on that
bus, except bus_set_realized() doesn't implement that, yet).
When realization of a component or bus fails, we need to roll back:
unrealize everything we realized so far. If any of these unrealizes
failed, the device would be left in an inconsistent state. Must not
happen.
device_set_realized() lets it happen: it ignores errors in the roll
back code starting at label child_realize_fail.
Since realization is recursive, unrealization must be recursive, too.
But how could a partly failed unrealize be rolled back? We'd have to
re-realize, which can fail. This design is fundamentally broken.
device_set_realized() does not roll back at all. Instead, it keeps
unrealizing, ignoring further errors.
It can screw up even for a device with no buses: if the lone
dc->unrealize() fails, it still unregisters vmstate, and calls
listeners' unrealize() callback.
bus_set_realized() does not roll back either. Instead, it stops
unrealizing.
Fortunately, no unrealize method can fail, as we'll see below.
To fix the design error, drop parameter @errp from all the unrealize
methods.
Any unrealize method that uses @errp now needs an update. This leads
us to unrealize() methods that can fail. Merely passing it to another
unrealize method cannot cause failure, though. Here are the ones that
do other things with @errp:
* virtio_serial_device_unrealize()
Fails when qbus_set_hotplug_handler() fails, but still does all the
other work. On failure, the device would stay realized with its
resources completely gone. Oops. Can't happen, because
qbus_set_hotplug_handler() can't actually fail here. Pass
&error_abort to qbus_set_hotplug_handler() instead.
* hw/ppc/spapr_drc.c's unrealize()
Fails when object_property_del() fails, but all the other work is
already done. On failure, the device would stay realized with its
vmstate registration gone. Oops. Can't happen, because
object_property_del() can't actually fail here. Pass &error_abort
to object_property_del() instead.
* spapr_phb_unrealize()
Fails and bails out when remove_drcs() fails, but other work is
already done. On failure, the device would stay realized with some
of its resources gone. Oops. remove_drcs() fails only when
chassis_from_bus()'s object_property_get_uint() fails, and it can't
here. Pass &error_abort to remove_drcs() instead.
Therefore, no unrealize method can fail before this patch.
device_set_realized()'s recursive unrealization via bus uses
object_property_set_bool(). Can't drop @errp there, so pass
&error_abort.
We similarly unrealize with object_property_set_bool() elsewhere,
always ignoring errors. Pass &error_abort instead.
Several unrealize methods no longer handle errors from other unrealize
methods: virtio_9p_device_unrealize(),
virtio_input_device_unrealize(), scsi_qdev_unrealize(), ...
Much of the deleted error handling looks wrong anyway.
One unrealize methods no longer ignore such errors:
usb_ehci_pci_exit().
Several realize methods no longer ignore errors when rolling back:
v9fs_device_realize_common(), pci_qdev_unrealize(),
spapr_phb_realize(), usb_qdev_realize(), vfio_ccw_realize(),
virtio_device_realize().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-17-armbru@redhat.com>
No reason for local_err here, use errp directly instead.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20191205174635.18758-21-vsementsov@virtuozzo.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
In my "build everything" tree, changing sysemu/sysemu.h triggers a
recompile of some 5400 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
Almost a third of its inclusions are actually superfluous. Delete
them. Downgrade two more to qapi/qapi-types-run-state.h, and move one
from char/serial.h to char/serial.c.
hw/semihosting/config.c, monitor/monitor.c, qdev-monitor.c, and
stubs/semihost.c define variables declared in sysemu/sysemu.h without
including it. The compiler is cool with that, but include it anyway.
This doesn't reduce actual use much, as it's still included into
widely included headers. The next commit will tackle that.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-27-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
In my "build everything" tree, changing hw/qdev-properties.h triggers
a recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
Many places including hw/qdev-properties.h (directly or via hw/qdev.h)
actually need only hw/qdev-core.h. Include hw/qdev-core.h there
instead.
hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h
and hw/qdev-properties.h, which in turn includes hw/qdev-core.h.
Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h.
While there, delete a few superfluous inclusions of hw/qdev-core.h.
Touching hw/qdev-properties.h now recompiles some 1200 objects.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190812052359.30071-22-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-20-armbru@redhat.com>
In my "build everything" tree, changing migration/vmstate.h triggers a
recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
hw/hw.h supposedly includes it for convenience. Several other headers
include it just to get VMStateDescription. The previous commit made
that unnecessary.
Include migration/vmstate.h only where it's still needed. Touching it
now recompiles only some 1600 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-16-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
It's recommended that VMStateDescription names are decoupled from QOM
type names as the latter may freely change without consideration of
migration compatibility.
Link: https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg02175.html
CC: qemu-trivial@nongnu.org
Signed-off-by: Li Qiang <liq3ea@163.com>
Message-Id: <20190521151543.92274-3-liq3ea@163.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Introduces hot plug/unplug support for the vfio-ap device.
To hot plug a vfio-ap device using the QEMU device_add command:
(qemu) device_add vfio-ap,sysfsdev=$path-to-mdev
Where $path-to-mdev is the absolute path to the mediated matrix device
to which AP resources to be used by the guest have been assigned.
A vfio-ap device can be hot plugged only if:
1. A vfio-ap device has not been attached to the virtual machine's ap-bus
via the QEMU command line or a prior hot plug action.
2. The guest was started with the CPU model feature for AP enabled
(e.g., -cpu host,ap=on)
To hot unplug a vfio-ap device using the QEMU device_del command:
(qemu) device_del vfio-ap,sysfsdev=$path-to-mdev
Where $path-to-mdev is the absolute path to the mediated matrix device
specified when the vfio-ap device was attached to the virtual machine's
ap-bus.
A vfio-ap device can be hot unplugged only if:
1. A vfio-ap device has been attached to the virtual machine's ap-bus
via the QEMU command line or a prior hot plug action.
2. The guest was started with the CPU model feature for AP enabled
(e.g., -cpu host,ap=on)
Please note that a hot plug handler is not necessary for the vfio-ap device
because the AP matrix configuration for the guest is performed by the
kernel device driver when the vfio-ap device is realized. The vfio-ap device
represents a VFIO mediated device created in the host sysfs for use by a guest.
The mdev device is configured with an AP matrix (i.e., adapters and domains) via
its sysfs attribute interfaces prior to starting the guest or plugging a vfio-ap
device in. When the device is realized, a file descriptor is opened on the mdev
device which results in a callback to the vfio_ap kernel device driver. The
device driver then configures the AP matrix in the guest's SIE state description
from the AP matrix assigned via the mdev device's sysfs interfaces. The AP
devices will be created for the guest when the AP bus running on the guest
subsequently performs its periodic scan for AP devices.
The qdev_simple_device_unplug_cb() callback function is used for the same
reaons; namely, the vfio_ap kernel device driver will perform the AP resource
de-configuration for the guest when the vfio-ap device is unplugged. When the
vfio-ap device is unrealized, the mdev device file descriptor is closed which
results in a callback to the vfio_ap kernel device driver. The device driver
then clears the AP matrix configuration in the guest's SIE state description
and resets all of the affected queues. The AP devices created for the guest
will be removed when the AP bus running on the guest subsequently performs
its periodic scan and finds there are no longer any AP resources assigned to the
guest.
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Pierre Morel <pmorel@linux.ibm.com>
Message-Id: <1550519397-25359-2-git-send-email-akrowiak@linux.ibm.com>
[CH: adapt to changed qbus_set_hotplug_handler() signature]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes, with the changes
to the following files manually reverted:
contrib/libvhost-user/libvhost-user-glib.h
contrib/libvhost-user/libvhost-user.c
contrib/libvhost-user/libvhost-user.h
linux-user/mips64/cpu_loop.c
linux-user/mips64/signal.c
linux-user/sparc64/cpu_loop.c
linux-user/sparc64/signal.c
linux-user/x86_64/cpu_loop.c
linux-user/x86_64/signal.c
target/s390x/gen-features.c
tests/migration/s390x/a-b-bios.c
tests/test-rcu-simpleq.c
tests/test-rcu-tailq.c
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181204172535.2799-1-armbru@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Acked-by: Yuval Shaia <yuval.shaia@oracle.com>
Acked-by: Viktor Prutyanov <viktor.prutyanov@phystech.edu>
vfio-ap devices do not pin any pages in the host. Therefore, they
are compatible with memory ballooning.
Flag them as compatible, so both vfio-ap and a balloon can be
used simultaneously.
Cc: qemu-stable@nongnu.org
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
If ioctl(..., VFIO_DEVICE_RESET) fails, we want to report errno
instead of ret (which is always -1 on error).
Fixes Coverity issue CID 1396176.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Introduces a VFIO based AP device. The device is defined via
the QEMU command line by specifying:
-device vfio-ap,sysfsdev=<path-to-mediated-matrix-device>
There may be only one vfio-ap device configured for a guest.
The mediated matrix device is created by the VFIO AP device
driver by writing a UUID to a sysfs attribute file (see
docs/vfio-ap.txt). The mediated matrix device will be named
after the UUID. Symbolic links to the $uuid are created in
many places, so the path to the mediated matrix device $uuid
can be specified in any of the following ways:
/sys/devices/vfio_ap/matrix/$uuid
/sys/devices/vfio_ap/matrix/mdev_supported_types/vfio_ap-passthrough/devices/$uuid
/sys/bus/mdev/devices/$uuid
/sys/bus/mdev/drivers/vfio_mdev/$uuid
When the vfio-ap device is realized, it acquires and opens the
VFIO iommu group to which the mediated matrix device is
bound. This causes a VFIO group notification event to be
signaled. The vfio_ap device driver's group notification
handler will get called at which time the device driver
will configure the the AP devices to which the guest will
be granted access.
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Tested-by: Pierre Morel <pmorel@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Pierre Morel <pmorel@linux.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20181010170309.12045-6-akrowiak@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[CH: added missing g_free and device category]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
