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 <zyimin@linux.vnet.ibm.com>
Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
Fei Li
2017-02-17 17:06:26 +08:00
committed by Christian Borntraeger
parent 08fab50da6
commit 5197839354
6 changed files with 114 additions and 0 deletions

View File

@@ -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