Libudev relies on having a subsystem link for non-root devices. To
avoid libudev (and potentially other userspace tools) choking on the
matrix device let us introduce a matrix bus and with it the matrix
bus subsytem. Also make the matrix device reside within the matrix
bus.
Doing this we remove the forced link from the matrix device to the
vfio_ap driver and the device_type we do not need anymore.
Since the associated matrix driver is not the vfio_ap driver any more,
we have to change the search for the devices on the vfio_ap driver in
the function vfio_ap_verify_queue_reserved.
Fixes: 1fde573413 ("s390: vfio-ap: base implementation of VFIO AP device driver")
Cc: stable@vger.kernel.org
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The driver uses test_facility(), but does not include the
corresponding include file explicitly. The driver currently builds
only thanks to the following include chain:
vfio_ap_drv.c
<linux/module.h>
<linux/elf.h>
<asm/elf.h>
<linux/compat.h>
<asm/uaccess.h>
<asm/facility.h>
Files should not rely on such fragile implicit includes.
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
no functional change, just hygiene.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Registers the matrix device created by the VFIO AP device
driver with the VFIO mediated device framework.
Registering the matrix device will create the sysfs
structures needed to create mediated matrix devices
each of which will be used to configure the AP matrix
for a guest and connect it to the VFIO AP device driver.
Registering the matrix device with the VFIO mediated device
framework will create the following sysfs structures:
/sys/devices/vfio_ap/matrix/
...... [mdev_supported_types]
......... [vfio_ap-passthrough]
............ create
To create a mediated device for the AP matrix device, write a UUID
to the create file:
uuidgen > create
A symbolic link to the mediated device's directory will be created in the
devices subdirectory named after the generated $uuid:
/sys/devices/vfio_ap/matrix/
...... [mdev_supported_types]
......... [vfio_ap-passthrough]
............ [devices]
............... [$uuid]
A symbolic link to the mediated device will also be created
in the vfio_ap matrix's directory:
/sys/devices/vfio_ap/matrix/[$uuid]
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Farhan Ali <alifm@linux.ibm.com>
Message-Id: <20180925231641.4954-6-akrowiak@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Introduces a new AP device driver. This device driver
is built on the VFIO mediated device framework. The framework
provides sysfs interfaces that facilitate passthrough
access by guests to devices installed on the linux host.
The VFIO AP device driver will serve two purposes:
1. Provide the interfaces to reserve AP devices for exclusive
use by KVM guests. This is accomplished by unbinding the
devices to be reserved for guest usage from the zcrypt
device driver and binding them to the VFIO AP device driver.
2. Implements the functions, callbacks and sysfs attribute
interfaces required to create one or more VFIO mediated
devices each of which will be used to configure the AP
matrix for a guest and serve as a file descriptor
for facilitating communication between QEMU and the
VFIO AP device driver.
When the VFIO AP device driver is initialized:
* It registers with the AP bus for control of type 10 (CEX4
and newer) AP queue devices. This limitation was imposed
due to:
1. A desire to keep the code as simple as possible;
2. Some older models are no longer supported by the kernel
and others are getting close to end of service.
3. A lack of older systems on which to test older devices.
The probe and remove callbacks will be provided to support
the binding/unbinding of AP queue devices to/from the VFIO
AP device driver.
* Creates a matrix device, /sys/devices/vfio_ap/matrix,
to serve as the parent of the mediated devices created, one
for each guest, and to hold the APQNs of the AP devices bound to
the VFIO AP device driver.
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Tested-by: Farhan Ali <alifm@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20180925231641.4954-5-akrowiak@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Pierre Morel