From 519783935451764b397f2a712de5ea778ff77fdf Mon Sep 17 00:00:00 2001 From: Fei Li Date: Fri, 17 Feb 2017 17:06:26 +0800 Subject: KVM: s390: introduce ais mode modify function Provide an interface for userspace to modify AIS (adapter-interruption-suppression) mode state, and add documentation for the interface. Allowed target modes are ALL-Interruptions mode and SINGLE-Interruption mode. We introduce the 'simm' and 'nimm' fields in kvm_s390_float_interrupt to store interruption modes for each ISC. Each bit in 'simm' and 'nimm' targets to one ISC, and collaboratively indicate three modes: ALL-Interruptions, SINGLE-Interruption and NO-Interruptions. This interface can initiate most transitions between the states; transition from SINGLE-Interruption to NO-Interruptions via adapter interrupt injection will be introduced in a following patch. The meaningful combinations are as follows: interruption mode | simm bit | nimm bit ------------------|----------|---------- ALL | 0 | 0 SINGLE | 1 | 0 NO | 1 | 1 Besides, add tracepoint to track AIS mode transitions. Co-Authored-By: Yi Min Zhao Signed-off-by: Yi Min Zhao Signed-off-by: Fei Li Reviewed-by: Cornelia Huck Signed-off-by: Christian Borntraeger --- arch/s390/include/asm/kvm_host.h | 10 ++++++++++ arch/s390/include/uapi/asm/kvm.h | 6 ++++++ arch/s390/kvm/interrupt.c | 43 ++++++++++++++++++++++++++++++++++++++++ arch/s390/kvm/kvm-s390.c | 4 ++++ arch/s390/kvm/trace-s390.h | 31 +++++++++++++++++++++++++++++ 5 files changed, 94 insertions(+) (limited to 'arch/s390') diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index 499c72c2280d..552c319483c6 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -521,6 +521,12 @@ struct kvm_s390_local_interrupt { #define FIRQ_CNTR_PFAULT 3 #define FIRQ_MAX_COUNT 4 +/* mask the AIS mode for a given ISC */ +#define AIS_MODE_MASK(isc) (0x80 >> isc) + +#define KVM_S390_AIS_MODE_ALL 0 +#define KVM_S390_AIS_MODE_SINGLE 1 + struct kvm_s390_float_interrupt { unsigned long pending_irqs; spinlock_t lock; @@ -530,6 +536,10 @@ struct kvm_s390_float_interrupt { struct kvm_s390_ext_info srv_signal; int next_rr_cpu; unsigned long idle_mask[BITS_TO_LONGS(KVM_MAX_VCPUS)]; + struct mutex ais_lock; + u8 simm; + u8 nimm; + int ais_enabled; }; struct kvm_hw_wp_info_arch { diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h index 5fa144d1df0a..50d2a927c990 100644 --- a/arch/s390/include/uapi/asm/kvm.h +++ b/arch/s390/include/uapi/asm/kvm.h @@ -26,6 +26,7 @@ #define KVM_DEV_FLIC_ADAPTER_REGISTER 6 #define KVM_DEV_FLIC_ADAPTER_MODIFY 7 #define KVM_DEV_FLIC_CLEAR_IO_IRQ 8 +#define KVM_DEV_FLIC_AISM 9 /* * We can have up to 4*64k pending subchannels + 8 adapter interrupts, * as well as up to ASYNC_PF_PER_VCPU*KVM_MAX_VCPUS pfault done interrupts. @@ -46,6 +47,11 @@ struct kvm_s390_io_adapter { #define KVM_S390_ADAPTER_SUPPRESSIBLE 0x01 +struct kvm_s390_ais_req { + __u8 isc; + __u16 mode; +}; + #define KVM_S390_IO_ADAPTER_MASK 1 #define KVM_S390_IO_ADAPTER_MAP 2 #define KVM_S390_IO_ADAPTER_UNMAP 3 diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index dba51ad62570..96b689e48c08 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -2152,6 +2152,45 @@ static int clear_io_irq(struct kvm *kvm, struct kvm_device_attr *attr) return 0; } +static int modify_ais_mode(struct kvm *kvm, struct kvm_device_attr *attr) +{ + struct kvm_s390_float_interrupt *fi = &kvm->arch.float_int; + struct kvm_s390_ais_req req; + int ret = 0; + + if (!fi->ais_enabled) + return -ENOTSUPP; + + if (copy_from_user(&req, (void __user *)attr->addr, sizeof(req))) + return -EFAULT; + + if (req.isc > MAX_ISC) + return -EINVAL; + + trace_kvm_s390_modify_ais_mode(req.isc, + (fi->simm & AIS_MODE_MASK(req.isc)) ? + (fi->nimm & AIS_MODE_MASK(req.isc)) ? + 2 : KVM_S390_AIS_MODE_SINGLE : + KVM_S390_AIS_MODE_ALL, req.mode); + + mutex_lock(&fi->ais_lock); + switch (req.mode) { + case KVM_S390_AIS_MODE_ALL: + fi->simm &= ~AIS_MODE_MASK(req.isc); + fi->nimm &= ~AIS_MODE_MASK(req.isc); + break; + case KVM_S390_AIS_MODE_SINGLE: + fi->simm |= AIS_MODE_MASK(req.isc); + fi->nimm &= ~AIS_MODE_MASK(req.isc); + break; + default: + ret = -EINVAL; + } + mutex_unlock(&fi->ais_lock); + + return ret; +} + static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) { int r = 0; @@ -2188,6 +2227,9 @@ static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) case KVM_DEV_FLIC_CLEAR_IO_IRQ: r = clear_io_irq(dev->kvm, attr); break; + case KVM_DEV_FLIC_AISM: + r = modify_ais_mode(dev->kvm, attr); + break; default: r = -EINVAL; } @@ -2207,6 +2249,7 @@ static int flic_has_attr(struct kvm_device *dev, case KVM_DEV_FLIC_ADAPTER_REGISTER: case KVM_DEV_FLIC_ADAPTER_MODIFY: case KVM_DEV_FLIC_CLEAR_IO_IRQ: + case KVM_DEV_FLIC_AISM: return 0; } return -ENXIO; diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index f83f18b77f3d..977cc1660a83 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -1515,6 +1515,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) kvm_s390_crypto_init(kvm); + mutex_init(&kvm->arch.float_int.ais_lock); + kvm->arch.float_int.simm = 0; + kvm->arch.float_int.nimm = 0; + kvm->arch.float_int.ais_enabled = 0; spin_lock_init(&kvm->arch.float_int.lock); for (i = 0; i < FIRQ_LIST_COUNT; i++) INIT_LIST_HEAD(&kvm->arch.float_int.lists[i]); diff --git a/arch/s390/kvm/trace-s390.h b/arch/s390/kvm/trace-s390.h index 396485bca191..b32994d1546a 100644 --- a/arch/s390/kvm/trace-s390.h +++ b/arch/s390/kvm/trace-s390.h @@ -280,6 +280,37 @@ TRACE_EVENT(kvm_s390_enable_disable_ibs, __entry->state ? "enabling" : "disabling", __entry->id) ); +/* + * Trace point for modifying ais mode for a given isc. + */ +TRACE_EVENT(kvm_s390_modify_ais_mode, + TP_PROTO(__u8 isc, __u16 from, __u16 to), + TP_ARGS(isc, from, to), + + TP_STRUCT__entry( + __field(__u8, isc) + __field(__u16, from) + __field(__u16, to) + ), + + TP_fast_assign( + __entry->isc = isc; + __entry->from = from; + __entry->to = to; + ), + + TP_printk("for isc %x, modifying interruption mode from %s to %s", + __entry->isc, + (__entry->from == KVM_S390_AIS_MODE_ALL) ? + "ALL-Interruptions Mode" : + (__entry->from == KVM_S390_AIS_MODE_SINGLE) ? + "Single-Interruption Mode" : "No-Interruptions Mode", + (__entry->to == KVM_S390_AIS_MODE_ALL) ? + "ALL-Interruptions Mode" : + (__entry->to == KVM_S390_AIS_MODE_SINGLE) ? + "Single-Interruption Mode" : "No-Interruptions Mode") + ); + #endif /* _TRACE_KVMS390_H */ -- cgit v1.2.3