KVM: s390: add KVM_S390_ZPCI_OP to manage guest zPCI devices (db1c875e) · Commits · EulixOS / Software / Kernel

Documentation/virt/kvm/api.rst

+47 −0

Original line number	Diff line number	Diff line
		@@ -5802,6 +5802,53 @@ of CPUID leaf 0xD on the host.

		This ioctl injects an event channel interrupt directly to the guest vCPU.

		4.137 KVM_S390_ZPCI_OP
		--------------------

		:Capability: KVM_CAP_S390_ZPCI_OP
		:Architectures: s390
		:Type: vm ioctl
		:Parameters: struct kvm_s390_zpci_op (in)
		:Returns: 0 on success, <0 on error

		Used to manage hardware-assisted virtualization features for zPCI devices.

		Parameters are specified via the following structure::

		struct kvm_s390_zpci_op {
		/* in */
		__u32 fh; /* target device */
		__u8 op; /* operation to perform */
		__u8 pad[3];
		union {
		/* for KVM_S390_ZPCIOP_REG_AEN */
		struct {
		__u64 ibv; /* Guest addr of interrupt bit vector */
		__u64 sb; /* Guest addr of summary bit */
		__u32 flags;
		__u32 noi; /* Number of interrupts */
		__u8 isc; /* Guest interrupt subclass */
		__u8 sbo; /* Offset of guest summary bit vector */
		__u16 pad;
		} reg_aen;
		__u64 reserved[8];
		} u;
		};

		The type of operation is specified in the "op" field.
		KVM_S390_ZPCIOP_REG_AEN is used to register the VM for adapter event
		notification interpretation, which will allow firmware delivery of adapter
		events directly to the vm, with KVM providing a backup delivery mechanism;
		KVM_S390_ZPCIOP_DEREG_AEN is used to subsequently disable interpretation of
		adapter event notifications.

		The target zPCI function must also be specified via the "fh" field. For the
		KVM_S390_ZPCIOP_REG_AEN operation, additional information to establish firmware
		delivery must be provided via the "reg_aen" struct.

		The "pad" and "reserved" fields may be used for future extensions and should be
		set to 0s by userspace.

		5. The kvm_run structure
		========================

arch/s390/kvm/kvm-s390.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -618,6 +618,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
		case KVM_CAP_S390_PROTECTED:
		r = is_prot_virt_host();
		break;
		case KVM_CAP_S390_ZPCI_OP:
		r = kvm_s390_pci_interp_allowed();
		break;
		default:
		r = 0;
		}
		@@ -2629,6 +2632,19 @@ long kvm_arch_vm_ioctl(struct file *filp,
		r = -EFAULT;
		break;
		}
		case KVM_S390_ZPCI_OP: {
		struct kvm_s390_zpci_op args;

		r = -EINVAL;
		if (!IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM))
		break;
		if (copy_from_user(&args, argp, sizeof(args))) {
		r = -EFAULT;
		break;
		}
		r = kvm_s390_pci_zpci_op(kvm, &args);
		break;
		}
		default:
		r = -ENOTTY;
		}

arch/s390/kvm/pci.c

+85 −0

Original line number	Diff line number	Diff line
		@@ -585,6 +585,91 @@ void kvm_s390_pci_clear_list(struct kvm *kvm)
		spin_unlock(&kvm->arch.kzdev_list_lock);
		}

		static struct zpci_dev get_zdev_from_kvm_by_fh(struct kvm kvm, u32 fh)
		{
		struct zpci_dev *zdev = NULL;
		struct kvm_zdev *kzdev;

		spin_lock(&kvm->arch.kzdev_list_lock);
		list_for_each_entry(kzdev, &kvm->arch.kzdev_list, entry) {
		if (kzdev->zdev->fh == fh) {
		zdev = kzdev->zdev;
		break;
		}
		}
		spin_unlock(&kvm->arch.kzdev_list_lock);

		return zdev;
		}

		static int kvm_s390_pci_zpci_reg_aen(struct zpci_dev *zdev,
		struct kvm_s390_zpci_op *args)
		{
		struct zpci_fib fib = {};
		bool hostflag;

		fib.fmt0.aibv = args->u.reg_aen.ibv;
		fib.fmt0.isc = args->u.reg_aen.isc;
		fib.fmt0.noi = args->u.reg_aen.noi;
		if (args->u.reg_aen.sb != 0) {
		fib.fmt0.aisb = args->u.reg_aen.sb;
		fib.fmt0.aisbo = args->u.reg_aen.sbo;
		fib.fmt0.sum = 1;
		} else {
		fib.fmt0.aisb = 0;
		fib.fmt0.aisbo = 0;
		fib.fmt0.sum = 0;
		}

		hostflag = !(args->u.reg_aen.flags & KVM_S390_ZPCIOP_REGAEN_HOST);
		return kvm_s390_pci_aif_enable(zdev, &fib, hostflag);
		}

		int kvm_s390_pci_zpci_op(struct kvm kvm, struct kvm_s390_zpci_op args)
		{
		struct kvm_zdev *kzdev;
		struct zpci_dev *zdev;
		int r;

		zdev = get_zdev_from_kvm_by_fh(kvm, args->fh);
		if (!zdev)
		return -ENODEV;

		mutex_lock(&zdev->kzdev_lock);
		mutex_lock(&kvm->lock);

		kzdev = zdev->kzdev;
		if (!kzdev) {
		r = -ENODEV;
		goto out;
		}
		if (kzdev->kvm != kvm) {
		r = -EPERM;
		goto out;
		}

		switch (args->op) {
		case KVM_S390_ZPCIOP_REG_AEN:
		/* Fail on unknown flags */
		if (args->u.reg_aen.flags & ~KVM_S390_ZPCIOP_REGAEN_HOST) {
		r = -EINVAL;
		break;
		}
		r = kvm_s390_pci_zpci_reg_aen(zdev, args);
		break;
		case KVM_S390_ZPCIOP_DEREG_AEN:
		r = kvm_s390_pci_aif_disable(zdev, false);
		break;
		default:
		r = -EINVAL;
		}

		out:
		mutex_unlock(&kvm->lock);
		mutex_unlock(&zdev->kzdev_lock);
		return r;
		}

		int kvm_s390_pci_init(void)
		{
		aift = kzalloc(sizeof(struct zpci_aift), GFP_KERNEL);

arch/s390/kvm/pci.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -59,6 +59,8 @@ void kvm_s390_pci_aen_exit(void);
		void kvm_s390_pci_init_list(struct kvm *kvm);
		void kvm_s390_pci_clear_list(struct kvm *kvm);

		int kvm_s390_pci_zpci_op(struct kvm kvm, struct kvm_s390_zpci_op args);

		int kvm_s390_pci_init(void);
		void kvm_s390_pci_exit(void);

include/uapi/linux/kvm.h

+31 −0

Original line number	Diff line number	Diff line
		@@ -1157,6 +1157,7 @@ struct kvm_ppc_resize_hpt {
		#define KVM_CAP_VM_TSC_CONTROL 214
		#define KVM_CAP_SYSTEM_EVENT_DATA 215
		#define KVM_CAP_ARM_SYSTEM_SUSPEND 216
		#define KVM_CAP_S390_ZPCI_OP 221

		#ifdef KVM_CAP_IRQ_ROUTING

		@@ -2118,4 +2119,34 @@ struct kvm_stats_desc {
		/* Available with KVM_CAP_XSAVE2 */
		#define KVM_GET_XSAVE2 _IOR(KVMIO, 0xcf, struct kvm_xsave)

		/* Available with KVM_CAP_S390_ZPCI_OP */
		#define KVM_S390_ZPCI_OP _IOW(KVMIO, 0xd1, struct kvm_s390_zpci_op)

		struct kvm_s390_zpci_op {
		/* in */
		__u32 fh; /* target device */
		__u8 op; /* operation to perform */
		__u8 pad[3];
		union {
		/* for KVM_S390_ZPCIOP_REG_AEN */
		struct {
		__u64 ibv; /* Guest addr of interrupt bit vector */
		__u64 sb; /* Guest addr of summary bit */
		__u32 flags;
		__u32 noi; /* Number of interrupts */
		__u8 isc; /* Guest interrupt subclass */
		__u8 sbo; /* Offset of guest summary bit vector */
		__u16 pad;
		} reg_aen;
		__u64 reserved[8];
		} u;
		};

		/* types for kvm_s390_zpci_op->op */
		#define KVM_S390_ZPCIOP_REG_AEN 0
		#define KVM_S390_ZPCIOP_DEREG_AEN 1

		/* flags for kvm_s390_zpci_op->u.reg_aen.flags */
		#define KVM_S390_ZPCIOP_REGAEN_HOST (1 << 0)

		#endif /* __LINUX_KVM_H */