From mboxrd@z Thu Jan 1 00:00:00 1970 From: Harald Freudenberger Subject: Re: [PATCH v6 08/21] s390: vfio-ap: register matrix device with VFIO mdev framework Date: Tue, 10 Jul 2018 09:03:22 +0200 Message-ID: <63062d1b-164f-8d7e-76bf-8e9b3ac23366@linux.ibm.com> References: <1530306683-7270-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1530306683-7270-9-git-send-email-akrowiak@linux.vnet.ibm.com> <198dfc60-96a8-5c46-f437-38bce5efcf20@linux.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <198dfc60-96a8-5c46-f437-38bce5efcf20@linux.ibm.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: pmorel@linux.ibm.com, 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 09.07.2018 16:17, Pierre Morel wrote: > 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" >> +#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 > > Why isn't it 256 x 256 ? In zcrypt.h there are defines for these: #define MAX_ZDEV_CARDIDS_EXT 256 #define MAX_ZDEV_DOMAINS_EXT 256 /* Maximum number of zcrypt devices */ #define MAX_ZDEV_ENTRIES_EXT (MAX_ZDEV_CARDIDS_EXT * MAX_ZDEV_DOMAINS_EXT) >>   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_ */ > >