linux/drivers/s390/crypto/vfio_ap_private.h

164 lines
5.5 KiB
C
Raw Normal View History

s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Private data and functions for adjunct processor VFIO matrix driver.
*
* Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
2018-09-25 19:16:20 -04:00
* Halil Pasic <pasic@linux.ibm.com>
* Pierre Morel <pmorel@linux.ibm.com>
s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
*
* Copyright IBM Corp. 2018
*/
#ifndef _VFIO_AP_PRIVATE_H_
#define _VFIO_AP_PRIVATE_H_
#include <linux/types.h>
#include <linux/mdev.h>
#include <linux/delay.h>
#include <linux/eventfd.h>
s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
#include <linux/mutex.h>
s390: ap: kvm: add PQAP interception for AQIC We prepare the interception of the PQAP/AQIC instruction for the case the AQIC facility is enabled in the guest. First of all we do not want to change existing behavior when intercepting AP instructions without the SIE allowing the guest to use AP instructions. In this patch we only handle the AQIC interception allowed by facility 65 which will be enabled when the complete interception infrastructure will be present. We add a callback inside the KVM arch structure for s390 for a VFIO driver to handle a specific response to the PQAP instruction with the AQIC command and only this command. But we want to be able to return a correct answer to the guest even there is no VFIO AP driver in the kernel. Therefor, we inject the correct exceptions from inside KVM for the case the callback is not initialized, which happens when the vfio_ap driver is not loaded. We do consider the responsibility of the driver to always initialize the PQAP callback if it defines queues by initializing the CRYCB for a guest. If the callback has been setup we call it. If not we setup an answer considering that no queue is available for the guest when no callback has been setup. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Acked-by: Harald Freudenberger <freude@linux.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-05-21 17:34:34 +02:00
#include <linux/kvm_host.h>
#include <linux/vfio.h>
s390/vfio-ap: manage link between queue struct and matrix mdev Let's create links between each queue device bound to the vfio_ap device driver and the matrix mdev to which the queue's APQN is assigned. The idea is to facilitate efficient retrieval of the objects representing the queue devices and matrix mdevs as well as to verify that a queue assigned to a matrix mdev is bound to the driver. The links will be created as follows: * When the queue device is probed, if its APQN is assigned to a matrix mdev, the structures representing the queue device and the matrix mdev will be linked. * When an adapter or domain is assigned to a matrix mdev, for each new APQN assigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be linked. The links will be removed as follows: * When the queue device is removed, if its APQN is assigned to a matrix mdev, the link from the structure representing the matrix mdev to the structure representing the queue will be removed. Since the storage allocated for the vfio_ap_queue will be freed, there is no need to remove the link to the matrix_mdev to which the queue's APQN is assigned. * When an adapter or domain is unassigned from a matrix mdev, for each APQN unassigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be unlinked. * When an mdev is removed, the link from any queues assigned to the mdev to the mdev will be removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-02-01 11:18:09 -05:00
#include <linux/hashtable.h>
s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
#include "ap_bus.h"
#define VFIO_AP_MODULE_NAME "vfio_ap"
#define VFIO_AP_DRV_NAME "vfio_ap"
/**
* struct ap_matrix_dev - Contains the data for the matrix device.
*
s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
* @device: generic device structure associated with the AP matrix device
2018-09-25 19:16:20 -04:00
* @info: the struct containing the output from the PQAP(QCI) instruction
* @mdev_list: the list of mediated matrix devices created
* @mdevs_lock: mutex for locking the AP matrix device. This lock will be
2018-09-25 19:16:20 -04:00
* taken every time we fiddle with state managed by the vfio_ap
* driver, be it using @mdev_list or writing the state of a
* single ap_matrix_mdev device. It's quite coarse but we don't
* expect much contention.
* @vfio_ap_drv: the vfio_ap device driver
s390/vfio-ap: introduce new mutex to control access to the KVM pointer The vfio_ap device driver registers for notification when the pointer to the KVM object for a guest is set. Recall that the KVM lock (kvm->lock) mutex must be taken outside of the matrix_dev->lock mutex to prevent the reporting by lockdep of a circular locking dependency (a.k.a., a lockdep splat): * see commit 0cc00c8d4050 ("Fix circular lockdep when setting/clearing crypto masks") * see commit 86956e70761b ("replace open coded locks for VFIO_GROUP_NOTIFY_SET_KVM notification") With the introduction of support for hot plugging/unplugging AP devices passed through to a KVM guest, a new guests_lock mutex is introduced to ensure the proper locking order is maintained: struct ap_matrix_dev { ... struct mutex guests_lock; ... } The matrix_dev->guests_lock controls access to the matrix_mdev instances that hold the state for AP devices that have been passed through to a KVM guest. This lock must be held to control access to the KVM pointer (matrix_mdev->kvm) while the vfio_ap device driver is using it to plug/unplug AP devices passed through to the KVM guest. Keep in mind, the proper locking order must be maintained whenever dynamically updating a KVM guest's APCB to plug/unplug adapters, domains and control domains: 1. matrix_dev->guests_lock: required to use the KVM pointer - stored in a struct ap_matrix_mdev instance - to update a KVM guest's APCB 2. matrix_mdev->kvm->lock: required to update a guest's APCB 3. matrix_dev->mdevs_lock: required to access data stored in a struct ap_matrix_mdev instance. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-09-23 22:21:58 -04:00
* @guests_lock: mutex for controlling access to a guest that is using AP
* devices passed through by the vfio_ap device driver. This lock
* will be taken when the AP devices are plugged into or unplugged
* from a guest, and when an ap_matrix_mdev device is added to or
* removed from @mdev_list or the list is iterated.
s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
*/
struct ap_matrix_dev {
struct device device;
2018-09-25 19:16:20 -04:00
struct ap_config_info info;
struct list_head mdev_list;
struct mutex mdevs_lock; /* serializes access to each ap_matrix_mdev */
struct ap_driver *vfio_ap_drv;
s390/vfio-ap: introduce new mutex to control access to the KVM pointer The vfio_ap device driver registers for notification when the pointer to the KVM object for a guest is set. Recall that the KVM lock (kvm->lock) mutex must be taken outside of the matrix_dev->lock mutex to prevent the reporting by lockdep of a circular locking dependency (a.k.a., a lockdep splat): * see commit 0cc00c8d4050 ("Fix circular lockdep when setting/clearing crypto masks") * see commit 86956e70761b ("replace open coded locks for VFIO_GROUP_NOTIFY_SET_KVM notification") With the introduction of support for hot plugging/unplugging AP devices passed through to a KVM guest, a new guests_lock mutex is introduced to ensure the proper locking order is maintained: struct ap_matrix_dev { ... struct mutex guests_lock; ... } The matrix_dev->guests_lock controls access to the matrix_mdev instances that hold the state for AP devices that have been passed through to a KVM guest. This lock must be held to control access to the KVM pointer (matrix_mdev->kvm) while the vfio_ap device driver is using it to plug/unplug AP devices passed through to the KVM guest. Keep in mind, the proper locking order must be maintained whenever dynamically updating a KVM guest's APCB to plug/unplug adapters, domains and control domains: 1. matrix_dev->guests_lock: required to use the KVM pointer - stored in a struct ap_matrix_mdev instance - to update a KVM guest's APCB 2. matrix_mdev->kvm->lock: required to update a guest's APCB 3. matrix_dev->mdevs_lock: required to access data stored in a struct ap_matrix_mdev instance. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-09-23 22:21:58 -04:00
struct mutex guests_lock; /* serializes access to each KVM guest */
struct mdev_parent parent;
struct mdev_type mdev_type;
struct mdev_type *mdev_types[1];
s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
};
extern struct ap_matrix_dev *matrix_dev;
2018-09-25 19:16:20 -04:00
/**
* struct ap_matrix - matrix of adapters, domains and control domains
2018-09-25 19:16:20 -04:00
*
* @apm_max: max adapter number in @apm
* @apm: identifies the AP adapters in the matrix
2018-09-25 19:16:20 -04:00
* @aqm_max: max domain number in @aqm
* @aqm: identifies the AP queues (domains) in the matrix
2018-09-25 19:16:20 -04:00
* @adm_max: max domain number in @adm
* @adm: identifies the AP control domains in the matrix
*
* The AP matrix is comprised of three bit masks identifying the adapters,
* queues (domains) and control domains that belong to an AP matrix. The bits in
* each mask, from left to right, correspond to IDs 0 to 255. When a bit is set
* the corresponding ID belongs to the matrix.
2018-09-25 19:16:20 -04:00
*/
struct ap_matrix {
unsigned long apm_max;
DECLARE_BITMAP(apm, 256);
unsigned long aqm_max;
DECLARE_BITMAP(aqm, 256);
unsigned long adm_max;
DECLARE_BITMAP(adm, 256);
};
s390/vfio-ap: manage link between queue struct and matrix mdev Let's create links between each queue device bound to the vfio_ap device driver and the matrix mdev to which the queue's APQN is assigned. The idea is to facilitate efficient retrieval of the objects representing the queue devices and matrix mdevs as well as to verify that a queue assigned to a matrix mdev is bound to the driver. The links will be created as follows: * When the queue device is probed, if its APQN is assigned to a matrix mdev, the structures representing the queue device and the matrix mdev will be linked. * When an adapter or domain is assigned to a matrix mdev, for each new APQN assigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be linked. The links will be removed as follows: * When the queue device is removed, if its APQN is assigned to a matrix mdev, the link from the structure representing the matrix mdev to the structure representing the queue will be removed. Since the storage allocated for the vfio_ap_queue will be freed, there is no need to remove the link to the matrix_mdev to which the queue's APQN is assigned. * When an adapter or domain is unassigned from a matrix mdev, for each APQN unassigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be unlinked. * When an mdev is removed, the link from any queues assigned to the mdev to the mdev will be removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-02-01 11:18:09 -05:00
/**
* struct ap_queue_table - a table of queue objects.
*
* @queues: a hashtable of queues (struct vfio_ap_queue).
*/
struct ap_queue_table {
DECLARE_HASHTABLE(queues, 8);
};
2018-09-25 19:16:20 -04:00
/**
* struct ap_matrix_mdev - Contains the data associated with a matrix mediated
* device.
* @vdev: the vfio device
* @node: allows the ap_matrix_mdev struct to be added to a list
2018-09-25 19:16:20 -04:00
* @matrix: the adapters, usage domains and control domains assigned to the
* mediated matrix device.
* @shadow_apcb: the shadow copy of the APCB field of the KVM guest's CRYCB
* @kvm: the struct holding guest's state
* @pqap_hook: the function pointer to the interception handler for the
* PQAP(AQIC) instruction.
* @mdev: the mediated device
s390/vfio-ap: manage link between queue struct and matrix mdev Let's create links between each queue device bound to the vfio_ap device driver and the matrix mdev to which the queue's APQN is assigned. The idea is to facilitate efficient retrieval of the objects representing the queue devices and matrix mdevs as well as to verify that a queue assigned to a matrix mdev is bound to the driver. The links will be created as follows: * When the queue device is probed, if its APQN is assigned to a matrix mdev, the structures representing the queue device and the matrix mdev will be linked. * When an adapter or domain is assigned to a matrix mdev, for each new APQN assigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be linked. The links will be removed as follows: * When the queue device is removed, if its APQN is assigned to a matrix mdev, the link from the structure representing the matrix mdev to the structure representing the queue will be removed. Since the storage allocated for the vfio_ap_queue will be freed, there is no need to remove the link to the matrix_mdev to which the queue's APQN is assigned. * When an adapter or domain is unassigned from a matrix mdev, for each APQN unassigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be unlinked. * When an mdev is removed, the link from any queues assigned to the mdev to the mdev will be removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-02-01 11:18:09 -05:00
* @qtable: table of queues (struct vfio_ap_queue) assigned to the mdev
* @req_trigger eventfd ctx for signaling userspace to return a device
s390/vfio-ap: handle config changed and scan complete notification This patch implements two new AP driver callbacks: void (*on_config_changed)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); void (*on_scan_complete)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); The on_config_changed callback is invoked at the start of the AP bus scan function when it determines that the host AP configuration information has changed since the previous scan. The vfio_ap device driver registers a callback function for this callback that performs the following operations: 1. Unplugs the adapters, domains and control domains removed from the host's AP configuration from the guests to which they are assigned in a single operation. 2. Stores bitmaps identifying the adapters, domains and control domains added to the host's AP configuration with the structure representing the mediated device. When the vfio_ap device driver's probe callback is subsequently invoked, the probe function will recognize that the queue is being probed due to a change in the host's AP configuration and the plugging of the queue into the guest will be bypassed. The on_scan_complete callback is invoked after the ap bus scan is completed if the host AP configuration data has changed. The vfio_ap device driver registers a callback function for this callback that hot plugs each queue and control domain added to the AP configuration for each guest using them in a single hot plug operation. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2022-04-04 09:40:10 -04:00
* @apm_add: bitmap of APIDs added to the host's AP configuration
* @aqm_add: bitmap of APQIs added to the host's AP configuration
* @adm_add: bitmap of control domain numbers added to the host's AP
* configuration
2018-09-25 19:16:20 -04:00
*/
struct ap_matrix_mdev {
struct vfio_device vdev;
2018-09-25 19:16:20 -04:00
struct list_head node;
struct ap_matrix matrix;
struct ap_matrix shadow_apcb;
struct kvm *kvm;
crypto_hook pqap_hook;
struct mdev_device *mdev;
s390/vfio-ap: manage link between queue struct and matrix mdev Let's create links between each queue device bound to the vfio_ap device driver and the matrix mdev to which the queue's APQN is assigned. The idea is to facilitate efficient retrieval of the objects representing the queue devices and matrix mdevs as well as to verify that a queue assigned to a matrix mdev is bound to the driver. The links will be created as follows: * When the queue device is probed, if its APQN is assigned to a matrix mdev, the structures representing the queue device and the matrix mdev will be linked. * When an adapter or domain is assigned to a matrix mdev, for each new APQN assigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be linked. The links will be removed as follows: * When the queue device is removed, if its APQN is assigned to a matrix mdev, the link from the structure representing the matrix mdev to the structure representing the queue will be removed. Since the storage allocated for the vfio_ap_queue will be freed, there is no need to remove the link to the matrix_mdev to which the queue's APQN is assigned. * When an adapter or domain is unassigned from a matrix mdev, for each APQN unassigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be unlinked. * When an mdev is removed, the link from any queues assigned to the mdev to the mdev will be removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-02-01 11:18:09 -05:00
struct ap_queue_table qtable;
struct eventfd_ctx *req_trigger;
s390/vfio-ap: handle config changed and scan complete notification This patch implements two new AP driver callbacks: void (*on_config_changed)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); void (*on_scan_complete)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); The on_config_changed callback is invoked at the start of the AP bus scan function when it determines that the host AP configuration information has changed since the previous scan. The vfio_ap device driver registers a callback function for this callback that performs the following operations: 1. Unplugs the adapters, domains and control domains removed from the host's AP configuration from the guests to which they are assigned in a single operation. 2. Stores bitmaps identifying the adapters, domains and control domains added to the host's AP configuration with the structure representing the mediated device. When the vfio_ap device driver's probe callback is subsequently invoked, the probe function will recognize that the queue is being probed due to a change in the host's AP configuration and the plugging of the queue into the guest will be bypassed. The on_scan_complete callback is invoked after the ap bus scan is completed if the host AP configuration data has changed. The vfio_ap device driver registers a callback function for this callback that hot plugs each queue and control domain added to the AP configuration for each guest using them in a single hot plug operation. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2022-04-04 09:40:10 -04:00
DECLARE_BITMAP(apm_add, AP_DEVICES);
DECLARE_BITMAP(aqm_add, AP_DOMAINS);
DECLARE_BITMAP(adm_add, AP_DOMAINS);
2018-09-25 19:16:20 -04:00
};
/**
* struct vfio_ap_queue - contains the data associated with a queue bound to the
* vfio_ap device driver
* @matrix_mdev: the matrix mediated device
* @saved_iova: the notification indicator byte (nib) address
* @apqn: the APQN of the AP queue device
* @saved_isc: the guest ISC registered with the GIB interface
s390/vfio-ap: manage link between queue struct and matrix mdev Let's create links between each queue device bound to the vfio_ap device driver and the matrix mdev to which the queue's APQN is assigned. The idea is to facilitate efficient retrieval of the objects representing the queue devices and matrix mdevs as well as to verify that a queue assigned to a matrix mdev is bound to the driver. The links will be created as follows: * When the queue device is probed, if its APQN is assigned to a matrix mdev, the structures representing the queue device and the matrix mdev will be linked. * When an adapter or domain is assigned to a matrix mdev, for each new APQN assigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be linked. The links will be removed as follows: * When the queue device is removed, if its APQN is assigned to a matrix mdev, the link from the structure representing the matrix mdev to the structure representing the queue will be removed. Since the storage allocated for the vfio_ap_queue will be freed, there is no need to remove the link to the matrix_mdev to which the queue's APQN is assigned. * When an adapter or domain is unassigned from a matrix mdev, for each APQN unassigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be unlinked. * When an mdev is removed, the link from any queues assigned to the mdev to the mdev will be removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-02-01 11:18:09 -05:00
* @mdev_qnode: allows the vfio_ap_queue struct to be added to a hashtable
* @reset_status: the status from the last reset of the queue
* @reset_work: work to wait for queue reset to complete
*/
struct vfio_ap_queue {
struct ap_matrix_mdev *matrix_mdev;
dma_addr_t saved_iova;
int apqn;
#define VFIO_AP_ISC_INVALID 0xff
unsigned char saved_isc;
s390/vfio-ap: manage link between queue struct and matrix mdev Let's create links between each queue device bound to the vfio_ap device driver and the matrix mdev to which the queue's APQN is assigned. The idea is to facilitate efficient retrieval of the objects representing the queue devices and matrix mdevs as well as to verify that a queue assigned to a matrix mdev is bound to the driver. The links will be created as follows: * When the queue device is probed, if its APQN is assigned to a matrix mdev, the structures representing the queue device and the matrix mdev will be linked. * When an adapter or domain is assigned to a matrix mdev, for each new APQN assigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be linked. The links will be removed as follows: * When the queue device is removed, if its APQN is assigned to a matrix mdev, the link from the structure representing the matrix mdev to the structure representing the queue will be removed. Since the storage allocated for the vfio_ap_queue will be freed, there is no need to remove the link to the matrix_mdev to which the queue's APQN is assigned. * When an adapter or domain is unassigned from a matrix mdev, for each APQN unassigned that references a queue device bound to the vfio_ap device driver, the structures representing the queue device and the matrix mdev will be unlinked. * When an mdev is removed, the link from any queues assigned to the mdev to the mdev will be removed. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-02-01 11:18:09 -05:00
struct hlist_node mdev_qnode;
struct ap_queue_status reset_status;
struct work_struct reset_work;
};
int vfio_ap_mdev_register(void);
void vfio_ap_mdev_unregister(void);
int vfio_ap_mdev_probe_queue(struct ap_device *queue);
void vfio_ap_mdev_remove_queue(struct ap_device *queue);
s390/vfio-ap: implement in-use callback for vfio_ap driver Let's implement the callback to indicate when an APQN is in use by the vfio_ap device driver. The callback is invoked whenever a change to the apmask or aqmask would result in one or more queue devices being removed from the driver. The vfio_ap device driver will indicate a resource is in use if the APQN of any of the queue devices to be removed are assigned to any of the matrix mdevs under the driver's control. There is potential for a deadlock condition between the matrix_dev->guests_lock used to lock the guest during assignment of adapters and domains and the ap_perms_mutex locked by the AP bus when changes are made to the sysfs apmask/aqmask attributes. The AP Perms lock controls access to the objects that store the adapter numbers (ap_perms) and domain numbers (aq_perms) for the sysfs /sys/bus/ap/apmask and /sys/bus/ap/aqmask attributes. These attributes identify which queues are reserved for the zcrypt default device drivers. Before allowing a bit to be removed from either mask, the AP bus must check with the vfio_ap device driver to verify that none of the queues are assigned to any of its mediated devices. The apmask/aqmask attributes can be written or read at any time from userspace, so care must be taken to prevent a deadlock with asynchronous operations that might be taking place in the vfio_ap device driver. For example, consider the following: 1. A system administrator assigns an adapter to a mediated device under the control of the vfio_ap device driver. The driver will need to first take the matrix_dev->guests_lock to potentially hot plug the adapter into the KVM guest. 2. At the same time, a system administrator sets a bit in the sysfs /sys/bus/ap/ap_mask attribute. To complete the operation, the AP bus must: a. Take the ap_perms_mutex lock to update the object storing the values for the /sys/bus/ap/ap_mask attribute. b. Call the vfio_ap device driver's in-use callback to verify that the queues now being reserved for the default zcrypt drivers are not assigned to a mediated device owned by the vfio_ap device driver. To do the verification, the in-use callback function takes the matrix_dev->guests_lock, but has to wait because it is already held by the operation in 1 above. 3. The vfio_ap device driver calls an AP bus function to verify that the new queues resulting from the assignment of the adapter in step 1 are not reserved for the default zcrypt device driver. This AP bus function tries to take the ap_perms_mutex lock but gets stuck waiting for the waiting for the lock due to step 2a above. Consequently, we have the following deadlock situation: matrix_dev->guests_lock locked (1) ap_perms_mutex lock locked (2a) Waiting for matrix_dev->gusts_lock (2b) which is currently held (1) Waiting for ap_perms_mutex lock (3) which is currently held (2a) To prevent this deadlock scenario, the function called in step 3 will no longer take the ap_perms_mutex lock and require the caller to take the lock. The lock will be the first taken by the adapter/domain assignment functions in the vfio_ap device driver to maintain the proper locking order. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2021-09-30 11:43:38 -04:00
int vfio_ap_mdev_resource_in_use(unsigned long *apm, unsigned long *aqm);
s390/vfio-ap: handle config changed and scan complete notification This patch implements two new AP driver callbacks: void (*on_config_changed)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); void (*on_scan_complete)(struct ap_config_info *new_config_info, struct ap_config_info *old_config_info); The on_config_changed callback is invoked at the start of the AP bus scan function when it determines that the host AP configuration information has changed since the previous scan. The vfio_ap device driver registers a callback function for this callback that performs the following operations: 1. Unplugs the adapters, domains and control domains removed from the host's AP configuration from the guests to which they are assigned in a single operation. 2. Stores bitmaps identifying the adapters, domains and control domains added to the host's AP configuration with the structure representing the mediated device. When the vfio_ap device driver's probe callback is subsequently invoked, the probe function will recognize that the queue is being probed due to a change in the host's AP configuration and the plugging of the queue into the guest will be bypassed. The on_scan_complete callback is invoked after the ap bus scan is completed if the host AP configuration data has changed. The vfio_ap device driver registers a callback function for this callback that hot plugs each queue and control domain added to the AP configuration for each guest using them in a single hot plug operation. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2022-04-04 09:40:10 -04:00
void vfio_ap_on_cfg_changed(struct ap_config_info *new_config_info,
struct ap_config_info *old_config_info);
void vfio_ap_on_scan_complete(struct ap_config_info *new_config_info,
struct ap_config_info *old_config_info);
s390: vfio-ap: base implementation of VFIO AP device driver 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>
2018-09-25 19:16:19 -04:00
#endif /* _VFIO_AP_PRIVATE_H_ */