These routines will be wired into a KVM ioctl, to be issued from userspace to (dis)associate a specific zPCI device with the issuing KVM. This will create/delete a relationship between KVM, zPCI device and the associated IOMMU domain for the device.
Signed-off-by: Matthew Rosato <[email protected]> --- arch/s390/include/asm/kvm_host.h | 2 + arch/s390/include/asm/kvm_pci.h | 2 + arch/s390/kvm/kvm-s390.c | 5 + arch/s390/kvm/pci.c | 225 +++++++++++++++++++++++++++++++ arch/s390/kvm/pci.h | 5 + 5 files changed, 239 insertions(+) diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index bf61ab05f98c..bd171abbb8ef 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -965,6 +965,8 @@ struct kvm_arch{ DECLARE_BITMAP(idle_mask, KVM_MAX_VCPUS); struct kvm_s390_gisa_interrupt gisa_int; struct kvm_s390_pv pv; + struct list_head kzdev_list; + spinlock_t kzdev_list_lock; }; #define KVM_HVA_ERR_BAD (-1UL) diff --git a/arch/s390/include/asm/kvm_pci.h b/arch/s390/include/asm/kvm_pci.h index ebc0da5d9ac1..47ce18b5bddd 100644 --- a/arch/s390/include/asm/kvm_pci.h +++ b/arch/s390/include/asm/kvm_pci.h @@ -21,6 +21,8 @@ struct kvm_zdev { struct zpci_dev *zdev; struct kvm *kvm; struct iommu_domain *dom; /* Used to invoke IOMMU API for RPCIT */ + struct notifier_block nb; + struct list_head entry; }; int kvm_s390_pci_dev_open(struct zpci_dev *zdev); diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index d91b2547f0bf..84acaf59a7d3 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2775,6 +2775,9 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) kvm_s390_crypto_init(kvm); + if (IS_ENABLED(CONFIG_VFIO_PCI)) + kvm_s390_pci_init_list(kvm); + mutex_init(&kvm->arch.float_int.ais_lock); spin_lock_init(&kvm->arch.float_int.lock); for (i = 0; i < FIRQ_LIST_COUNT; i++) @@ -2860,6 +2863,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm) if (!kvm_is_ucontrol(kvm)) gmap_remove(kvm->arch.gmap); kvm_s390_destroy_adapters(kvm); + if (IS_ENABLED(CONFIG_VFIO_PCI)) + kvm_s390_pci_clear_list(kvm); kvm_s390_clear_float_irqs(kvm); kvm_s390_vsie_destroy(kvm); KVM_EVENT(3, "vm 0x%pK destroyed", kvm); diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c index 1c42d25de697..28fe95f13c33 100644 --- a/arch/s390/kvm/pci.c +++ b/arch/s390/kvm/pci.c @@ -9,6 +9,7 @@ #include <linux/kvm_host.h> #include <linux/pci.h> +#include <linux/vfio.h> #include <asm/kvm_pci.h> #include <asm/pci.h> #include <asm/pci_insn.h> @@ -23,6 +24,22 @@ static inline int __set_irq_noiib(u16 ctl, u8 isc) return zpci_set_irq_ctrl(ctl, isc, &iib); } +static struct kvm_zdev *get_kzdev_by_fh(struct kvm *kvm, u32 fh) +{ + struct kvm_zdev *kzdev, *retval = NULL; + + spin_lock(&kvm->arch.kzdev_list_lock); + list_for_each_entry(kzdev, &kvm->arch.kzdev_list, entry) { + if (kzdev->zdev->fh == fh) { + retval = kzdev; + break; + } + } + spin_unlock(&kvm->arch.kzdev_list_lock); + + return retval; +} + /* Caller must hold the aift lock before calling this function */ void kvm_s390_pci_aen_exit(void) { @@ -153,6 +170,20 @@ int kvm_s390_pci_aen_init(u8 nisc) return rc; } +static int kvm_s390_pci_group_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct kvm_zdev *kzdev = container_of(nb, struct kvm_zdev, nb); + + if (action == VFIO_GROUP_NOTIFY_SET_KVM) { + if (!data || !kzdev->zdev) + return NOTIFY_DONE; + kzdev->kvm = data; + } + + return NOTIFY_OK; +} + int kvm_s390_pci_dev_open(struct zpci_dev *zdev) { struct kvm_zdev *kzdev; @@ -179,6 +210,200 @@ void kvm_s390_pci_dev_release(struct zpci_dev *zdev) } EXPORT_SYMBOL_GPL(kvm_s390_pci_dev_release); +static struct vfio_device *get_vdev(struct device *dev) +{ + struct vfio_device *(*fn)(struct device *dev); + struct vfio_device *vdev; + + fn = symbol_get(vfio_device_get_from_dev); + if (!fn) + return NULL; + + vdev = fn(dev); + + symbol_put(vfio_device_get_from_dev); + + return vdev; +} + +static void put_vdev(struct vfio_device *vdev) +{ + void (*fn)(struct vfio_device *vdev); + + fn = symbol_get(vfio_device_put); + if (!fn) + return; + + fn(vdev); + + symbol_put(vfio_device_put); +} + +static int register_notifier(struct device *dev, struct notifier_block *nb) +{ + int (*fn)(struct device *dev, enum vfio_notify_type type, + unsigned long *events, struct notifier_block *nb); + unsigned long events = VFIO_GROUP_NOTIFY_SET_KVM; + int rc; + + fn = symbol_get(vfio_register_notifier); + if (!fn) + return -EINVAL; + + rc = fn(dev, VFIO_GROUP_NOTIFY, &events, nb); + + symbol_put(vfio_register_notifier); + + return rc; +} + +static int unregister_notifier(struct device *dev, struct notifier_block *nb) +{ + int (*fn)(struct device *dev, enum vfio_notify_type type, + struct notifier_block *nb); + int rc; + + fn = symbol_get(vfio_unregister_notifier); + if (!fn) + return -EINVAL; + + rc = fn(dev, VFIO_GROUP_NOTIFY, nb); + + symbol_put(vfio_unregister_notifier); + + return rc; +} + +int kvm_s390_pci_zpci_start(struct kvm *kvm, struct zpci_dev *zdev) +{ + struct vfio_device *vdev; + struct pci_dev *pdev; + int rc; + + rc = kvm_s390_pci_dev_open(zdev); + if (rc) + return rc; + + pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn); + if (!pdev) { + rc = -ENODEV; + goto exit_err; + } + + vdev = get_vdev(&pdev->dev); + if (!vdev) { + pci_dev_put(pdev); + rc = -ENODEV; + goto exit_err; + } + + zdev->kzdev->nb.notifier_call = kvm_s390_pci_group_notifier; + + /* + * At this point, a KVM should already be associated with this device, + * so registering the notifier now should immediately trigger the + * event. We also want to know if the KVM association is later removed + * to ensure proper cleanup happens. + */ + rc = register_notifier(vdev->dev, &zdev->kzdev->nb); + + put_vdev(vdev); + pci_dev_put(pdev); + + /* Make sure the registered KVM matches the KVM issuing the ioctl */ + if (rc || zdev->kzdev->kvm != kvm) { + rc = -ENODEV; + goto exit_err; + } + + /* Must support KVM-managed IOMMU to proceed */ + if (IS_ENABLED(CONFIG_S390_KVM_IOMMU)) + rc = zpci_iommu_attach_kvm(zdev, kvm); + else + rc = -EINVAL; + + if (rc) + goto exit_err; + + spin_lock(&kvm->arch.kzdev_list_lock); + list_add_tail(&zdev->kzdev->entry, &kvm->arch.kzdev_list); + spin_unlock(&kvm->arch.kzdev_list_lock); + return 0; + +exit_err: + kvm_s390_pci_dev_release(zdev); + return rc; +} + +int kvm_s390_pci_zpci_stop(struct kvm *kvm, struct zpci_dev *zdev) +{ + struct vfio_device *vdev; + struct pci_dev *pdev; + int rc = 0; + + if (!zdev || !zdev->kzdev) + return -EINVAL; + + pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn); + if (!pdev) { + rc = -ENODEV; + goto exit_err; + } + + vdev = get_vdev(&pdev->dev); + if (!vdev) { + pci_dev_put(pdev); + rc = -ENODEV; + goto exit_err; + } + + spin_lock(&kvm->arch.kzdev_list_lock); + list_del(&zdev->kzdev->entry); + spin_unlock(&kvm->arch.kzdev_list_lock); + + rc = unregister_notifier(vdev->dev, &zdev->kzdev->nb); + + put_vdev(vdev); + pci_dev_put(pdev); + +exit_err: + kvm_s390_pci_dev_release(zdev); + return rc; +} + +void kvm_s390_pci_init_list(struct kvm *kvm) +{ + spin_lock_init(&kvm->arch.kzdev_list_lock); + INIT_LIST_HEAD(&kvm->arch.kzdev_list); +} + +void kvm_s390_pci_clear_list(struct kvm *kvm) +{ + struct kvm_zdev *tmp, *kzdev; + struct vfio_device *vdev; + struct pci_dev *pdev; + LIST_HEAD(remove); + + spin_lock(&kvm->arch.kzdev_list_lock); + list_for_each_entry_safe(kzdev, tmp, &kvm->arch.kzdev_list, entry) + list_move_tail(&kzdev->entry, &remove); + spin_unlock(&kvm->arch.kzdev_list_lock); + + list_for_each_entry_safe(kzdev, tmp, &remove, entry) { + pdev = pci_get_slot(kzdev->zdev->zbus->bus, kzdev->zdev->devfn); + if (pdev) { + vdev = get_vdev(&pdev->dev); + if (vdev) { + unregister_notifier(vdev->dev, + &kzdev->nb); + put_vdev(vdev); + } + pci_dev_put(pdev); + } + kvm_s390_pci_dev_release(kzdev->zdev); + } +} + int kvm_s390_pci_init(void) { aift = kzalloc(sizeof(struct zpci_aift), GFP_KERNEL); diff --git a/arch/s390/kvm/pci.h b/arch/s390/kvm/pci.h index 25cb1c787190..a95d9fdc91be 100644 --- a/arch/s390/kvm/pci.h +++ b/arch/s390/kvm/pci.h @@ -47,6 +47,11 @@ static inline struct kvm *kvm_s390_pci_si_to_kvm(struct zpci_aift *aift, int kvm_s390_pci_aen_init(u8 nisc); void kvm_s390_pci_aen_exit(void); +int kvm_s390_pci_zpci_start(struct kvm *kvm, struct zpci_dev *zdev); +int kvm_s390_pci_zpci_stop(struct kvm *kvm, struct zpci_dev *zdev); +void kvm_s390_pci_init_list(struct kvm *kvm); +void kvm_s390_pci_clear_list(struct kvm *kvm); + int kvm_s390_pci_init(void); #endif /* __KVM_S390_PCI_H */ -- 2.27.0 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
