From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre Morel Subject: Re: [PATCH v6 08/21] s390: vfio-ap: register matrix device with VFIO mdev framework Date: Mon, 9 Jul 2018 17:44:11 +0200 Message-ID: References: <1530306683-7270-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1530306683-7270-9-git-send-email-akrowiak@linux.vnet.ibm.com> Reply-To: pmorel@linux.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <1530306683-7270-9-git-send-email-akrowiak@linux.vnet.ibm.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Tony Krowiak , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com, kwankhede@nvidia.com, bjsdjshi@linux.vnet.ibm.com, pbonzini@redhat.com, alex.williamson@redhat.com, pmorel@linux.vnet.ibm.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, berrange@redhat.com, fiuczy@linux.vnet.ibm.com, buendgen@de.ibm.com, Tony Krowiak List-ID: On 29/06/2018 23:11, Tony Krowiak wrote: > 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] > > Signed-off-by: Tony Krowiak > --- > MAINTAINERS | 1 + > drivers/s390/crypto/Makefile | 2 +- > drivers/s390/crypto/vfio_ap_drv.c | 9 ++ > drivers/s390/crypto/vfio_ap_ops.c | 131 +++++++++++++++++++++++++++++++++ > drivers/s390/crypto/vfio_ap_private.h | 22 +++++- > 5 files changed, 161 insertions(+), 4 deletions(-) > create mode 100644 drivers/s390/crypto/vfio_ap_ops.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 0515dae..3217803 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -12410,6 +12410,7 @@ W: http://www.ibm.com/developerworks/linux/linux390/ > S: Supported > F: drivers/s390/crypto/vfio_ap_drv.c > F: drivers/s390/crypto/vfio_ap_private.h > +F: drivers/s390/crypto/vfio_ap_ops.c > > S390 ZFCP DRIVER > M: Steffen Maier > diff --git a/drivers/s390/crypto/Makefile b/drivers/s390/crypto/Makefile > index 48e466e..8d36b05 100644 > --- a/drivers/s390/crypto/Makefile > +++ b/drivers/s390/crypto/Makefile > @@ -17,5 +17,5 @@ pkey-objs := pkey_api.o > obj-$(CONFIG_PKEY) += pkey.o > > # adjunct processor matrix > -vfio_ap-objs := vfio_ap_drv.o > +vfio_ap-objs := vfio_ap_drv.o vfio_ap_ops.o > obj-$(CONFIG_VFIO_AP) += vfio_ap.o > diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c > index 93db312..b6ff7a4 100644 > --- a/drivers/s390/crypto/vfio_ap_drv.c > +++ b/drivers/s390/crypto/vfio_ap_drv.c > @@ -127,11 +127,20 @@ int __init vfio_ap_init(void) > return ret; > } > > + ret = vfio_ap_mdev_register(matrix_dev); > + if (ret) { > + ap_driver_unregister(&vfio_ap_drv); > + vfio_ap_matrix_dev_destroy(matrix_dev); > + > + return ret; > + } > + > return 0; > } > > void __exit vfio_ap_exit(void) > { > + vfio_ap_mdev_unregister(matrix_dev); > ap_driver_unregister(&vfio_ap_drv); > vfio_ap_matrix_dev_destroy(matrix_dev); > } > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > new file mode 100644 > index 0000000..4e61e33 > --- /dev/null > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -0,0 +1,131 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Adjunct processor matrix VFIO device driver callbacks. > + * > + * Copyright IBM Corp. 2018 > + * Author(s): Tony Krowiak > + * > + */ > +#include > +#include > +#include > +#include > +#include > + > +#include "vfio_ap_private.h" > + > +#define VFOP_AP_MDEV_TYPE_HWVIRT "passthrough" Isn't it a tipping fault ? VFIO != VFOP > +#define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device" > + > +DEFINE_SPINLOCK(mdev_list_lock); > +LIST_HEAD(mdev_list); > + > +static int vfio_ap_mdev_create(struct kobject *kobj, struct mdev_device *mdev) > +{ > + struct ap_matrix_dev *matrix_dev = > + to_ap_matrix_dev(mdev_parent_dev(mdev)); > + struct ap_matrix_mdev *matrix_mdev; > + > + matrix_mdev = kzalloc(sizeof(*matrix_mdev), GFP_KERNEL); > + if (!matrix_mdev) > + return -ENOMEM; > + > + matrix_mdev->name = dev_name(mdev_dev(mdev)); > + mdev_set_drvdata(mdev, matrix_mdev); > + > + if (atomic_dec_if_positive(&matrix_dev->available_instances) < 0) { > + kfree(matrix_mdev); > + return -EPERM; > + } > + > + spin_lock_bh(&mdev_list_lock); > + list_add(&matrix_mdev->list, &mdev_list); > + spin_unlock_bh(&mdev_list_lock); > + > + return 0; > +} > + > +static int vfio_ap_mdev_remove(struct mdev_device *mdev) > +{ > + struct ap_matrix_dev *matrix_dev = > + to_ap_matrix_dev(mdev_parent_dev(mdev)); > + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); > + > + spin_lock_bh(&mdev_list_lock); > + list_del(&matrix_mdev->list); > + spin_unlock_bh(&mdev_list_lock); > + kfree(matrix_mdev); > + mdev_set_drvdata(mdev, NULL); > + atomic_inc(&matrix_dev->available_instances); > + > + return 0; > +} > + > +static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf) > +{ > + return sprintf(buf, "%s\n", VFIO_AP_MDEV_NAME_HWVIRT); > +} > + > +MDEV_TYPE_ATTR_RO(name); > + > +static ssize_t available_instances_show(struct kobject *kobj, > + struct device *dev, char *buf) > +{ > + struct ap_matrix_dev *matrix_dev = to_ap_matrix_dev(dev); > + > + return sprintf(buf, "%d\n", > + atomic_read(&matrix_dev->available_instances)); > +} > + > +MDEV_TYPE_ATTR_RO(available_instances); > + > +static ssize_t device_api_show(struct kobject *kobj, struct device *dev, > + char *buf) > +{ > + return sprintf(buf, "%s\n", VFIO_DEVICE_API_AP_STRING); > +} > + > +MDEV_TYPE_ATTR_RO(device_api); > + > +static struct attribute *vfio_ap_mdev_type_attrs[] = { > + &mdev_type_attr_name.attr, > + &mdev_type_attr_device_api.attr, > + &mdev_type_attr_available_instances.attr, > + NULL, > +}; > + > +static struct attribute_group vfio_ap_mdev_hwvirt_type_group = { > + .name = VFOP_AP_MDEV_TYPE_HWVIRT, > + .attrs = vfio_ap_mdev_type_attrs, > +}; > + > +static struct attribute_group *vfio_ap_mdev_type_groups[] = { > + &vfio_ap_mdev_hwvirt_type_group, > + NULL, > +}; > + > +static const struct mdev_parent_ops vfio_ap_matrix_ops = { > + .owner = THIS_MODULE, > + .supported_type_groups = vfio_ap_mdev_type_groups, > + .create = vfio_ap_mdev_create, > + .remove = vfio_ap_mdev_remove, > +}; > + > +int vfio_ap_mdev_register(struct ap_matrix_dev *matrix_dev) > +{ > + int ret; > + > + ret = mdev_register_device(&matrix_dev->device, &vfio_ap_matrix_ops); > + if (ret) > + return ret; > + > + atomic_set(&matrix_dev->available_instances, > + AP_MATRIX_MAX_AVAILABLE_INSTANCES); > + > + return 0; > +} > + > +void vfio_ap_mdev_unregister(struct ap_matrix_dev *matrix_dev) > +{ > + mdev_unregister_device(&matrix_dev->device); > +} > diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h > index 19c0b60..3de1275 100644 > --- a/drivers/s390/crypto/vfio_ap_private.h > +++ b/drivers/s390/crypto/vfio_ap_private.h > @@ -10,20 +10,36 @@ > #define _VFIO_AP_PRIVATE_H_ > > #include > +#include > +#include > > #include "ap_bus.h" > > #define VFIO_AP_MODULE_NAME "vfio_ap" > #define VFIO_AP_DRV_NAME "vfio_ap" > +/** > + * There must be one mediated matrix device for every guest using AP devices. > + * If every APQN is assigned to a guest, then the maximum number of guests with > + * a unique APQN assigned would be 255 adapters x 255 domains = 72351 guests. > + */ > +#define AP_MATRIX_MAX_AVAILABLE_INSTANCES 72351 > > struct ap_matrix_dev { > struct device device; > + atomic_t available_instances; > +}; > + > +struct ap_matrix_mdev { > + const char *name; > + struct list_head list; > }; > > -static inline struct ap_matrix_dev > -*to_ap_matrix_parent_dev(struct device *dev) > +static struct ap_matrix_dev *to_ap_matrix_dev(struct device *dev) > { > - return container_of(dev, struct ap_matrix_dev, device.parent); > + return container_of(dev, struct ap_matrix_dev, device); > } > > +extern int vfio_ap_mdev_register(struct ap_matrix_dev *matrix_dev); > +extern void vfio_ap_mdev_unregister(struct ap_matrix_dev *matrix_dev); > + > #endif /* _VFIO_AP_PRIVATE_H_ */ -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany