Commit 51978393 authored by Fei Li's avatar Fei Li Committed by Christian Borntraeger

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: default avatarYi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: default avatarYi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: default avatarFei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
parent 08fab50d
...@@ -14,6 +14,7 @@ FLIC provides support to ...@@ -14,6 +14,7 @@ FLIC provides support to
- purge one pending floating I/O interrupt (KVM_DEV_FLIC_CLEAR_IO_IRQ) - purge one pending floating I/O interrupt (KVM_DEV_FLIC_CLEAR_IO_IRQ)
- enable/disable for the guest transparent async page faults - enable/disable for the guest transparent async page faults
- register and modify adapter interrupt sources (KVM_DEV_FLIC_ADAPTER_*) - register and modify adapter interrupt sources (KVM_DEV_FLIC_ADAPTER_*)
- modify AIS (adapter-interruption-suppression) mode state (KVM_DEV_FLIC_AISM)
Groups: Groups:
KVM_DEV_FLIC_ENQUEUE KVM_DEV_FLIC_ENQUEUE
...@@ -107,6 +108,25 @@ struct kvm_s390_io_adapter_req { ...@@ -107,6 +108,25 @@ struct kvm_s390_io_adapter_req {
release a userspace page for the translated address specified in addr release a userspace page for the translated address specified in addr
from the list of mappings from the list of mappings
KVM_DEV_FLIC_AISM
modify the adapter-interruption-suppression mode for a given isc if the
AIS capability is enabled. Takes a kvm_s390_ais_req describing:
struct kvm_s390_ais_req {
__u8 isc;
__u16 mode;
};
isc contains the target I/O interruption subclass, mode the target
adapter-interruption-suppression mode. The following modes are
currently supported:
- KVM_S390_AIS_MODE_ALL: ALL-Interruptions Mode, i.e. airq injection
is always allowed;
- KVM_S390_AIS_MODE_SINGLE: SINGLE-Interruption Mode, i.e. airq
injection is only allowed once and the following adapter interrupts
will be suppressed until the mode is set again to ALL-Interruptions
or SINGLE-Interruption mode.
Note: The KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR device ioctls executed on Note: The KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR device ioctls executed on
FLIC with an unknown group or attribute gives the error code EINVAL (instead of FLIC with an unknown group or attribute gives the error code EINVAL (instead of
ENXIO, as specified in the API documentation). It is not possible to conclude ENXIO, as specified in the API documentation). It is not possible to conclude
......
...@@ -521,6 +521,12 @@ struct kvm_s390_local_interrupt { ...@@ -521,6 +521,12 @@ struct kvm_s390_local_interrupt {
#define FIRQ_CNTR_PFAULT 3 #define FIRQ_CNTR_PFAULT 3
#define FIRQ_MAX_COUNT 4 #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 { struct kvm_s390_float_interrupt {
unsigned long pending_irqs; unsigned long pending_irqs;
spinlock_t lock; spinlock_t lock;
...@@ -530,6 +536,10 @@ struct kvm_s390_float_interrupt { ...@@ -530,6 +536,10 @@ struct kvm_s390_float_interrupt {
struct kvm_s390_ext_info srv_signal; struct kvm_s390_ext_info srv_signal;
int next_rr_cpu; int next_rr_cpu;
unsigned long idle_mask[BITS_TO_LONGS(KVM_MAX_VCPUS)]; 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 { struct kvm_hw_wp_info_arch {
......
...@@ -26,6 +26,7 @@ ...@@ -26,6 +26,7 @@
#define KVM_DEV_FLIC_ADAPTER_REGISTER 6 #define KVM_DEV_FLIC_ADAPTER_REGISTER 6
#define KVM_DEV_FLIC_ADAPTER_MODIFY 7 #define KVM_DEV_FLIC_ADAPTER_MODIFY 7
#define KVM_DEV_FLIC_CLEAR_IO_IRQ 8 #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, * 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. * as well as up to ASYNC_PF_PER_VCPU*KVM_MAX_VCPUS pfault done interrupts.
...@@ -46,6 +47,11 @@ struct kvm_s390_io_adapter { ...@@ -46,6 +47,11 @@ struct kvm_s390_io_adapter {
#define KVM_S390_ADAPTER_SUPPRESSIBLE 0x01 #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_MASK 1
#define KVM_S390_IO_ADAPTER_MAP 2 #define KVM_S390_IO_ADAPTER_MAP 2
#define KVM_S390_IO_ADAPTER_UNMAP 3 #define KVM_S390_IO_ADAPTER_UNMAP 3
......
...@@ -2152,6 +2152,45 @@ static int clear_io_irq(struct kvm *kvm, struct kvm_device_attr *attr) ...@@ -2152,6 +2152,45 @@ static int clear_io_irq(struct kvm *kvm, struct kvm_device_attr *attr)
return 0; 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) static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{ {
int r = 0; int r = 0;
...@@ -2188,6 +2227,9 @@ static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) ...@@ -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: case KVM_DEV_FLIC_CLEAR_IO_IRQ:
r = clear_io_irq(dev->kvm, attr); r = clear_io_irq(dev->kvm, attr);
break; break;
case KVM_DEV_FLIC_AISM:
r = modify_ais_mode(dev->kvm, attr);
break;
default: default:
r = -EINVAL; r = -EINVAL;
} }
...@@ -2207,6 +2249,7 @@ static int flic_has_attr(struct kvm_device *dev, ...@@ -2207,6 +2249,7 @@ static int flic_has_attr(struct kvm_device *dev,
case KVM_DEV_FLIC_ADAPTER_REGISTER: case KVM_DEV_FLIC_ADAPTER_REGISTER:
case KVM_DEV_FLIC_ADAPTER_MODIFY: case KVM_DEV_FLIC_ADAPTER_MODIFY:
case KVM_DEV_FLIC_CLEAR_IO_IRQ: case KVM_DEV_FLIC_CLEAR_IO_IRQ:
case KVM_DEV_FLIC_AISM:
return 0; return 0;
} }
return -ENXIO; return -ENXIO;
......
...@@ -1515,6 +1515,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) ...@@ -1515,6 +1515,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
kvm_s390_crypto_init(kvm); 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); spin_lock_init(&kvm->arch.float_int.lock);
for (i = 0; i < FIRQ_LIST_COUNT; i++) for (i = 0; i < FIRQ_LIST_COUNT; i++)
INIT_LIST_HEAD(&kvm->arch.float_int.lists[i]); INIT_LIST_HEAD(&kvm->arch.float_int.lists[i]);
......
...@@ -280,6 +280,37 @@ TRACE_EVENT(kvm_s390_enable_disable_ibs, ...@@ -280,6 +280,37 @@ TRACE_EVENT(kvm_s390_enable_disable_ibs,
__entry->state ? "enabling" : "disabling", __entry->id) __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 */ #endif /* _TRACE_KVMS390_H */
......
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