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| author | Fei Li <sherrylf@linux.vnet.ibm.com> | 2017-02-17 10:06:26 +0100 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2017-04-06 13:15:36 +0200 |
| commit | 519783935451764b397f2a712de5ea778ff77fdf (patch) | |
| tree | 599467b03f2ff2680b4de7b494b1bfaccd37f859 /Documentation/virtual | |
| parent | KVM: s390: interface for suppressible I/O adapters (diff) | |
| download | linux-519783935451764b397f2a712de5ea778ff77fdf.tar.xz linux-519783935451764b397f2a712de5ea778ff77fdf.zip | |
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>
Diffstat (limited to 'Documentation/virtual')
| -rw-r--r-- | Documentation/virtual/kvm/devices/s390_flic.txt | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/s390_flic.txt b/Documentation/virtual/kvm/devices/s390_flic.txt index e8ee3b6edb05..dfd42fd4abd5 100644 --- a/Documentation/virtual/kvm/devices/s390_flic.txt +++ b/Documentation/virtual/kvm/devices/s390_flic.txt @@ -14,6 +14,7 @@ FLIC provides support to - purge one pending floating I/O interrupt (KVM_DEV_FLIC_CLEAR_IO_IRQ) - enable/disable for the guest transparent async page faults - register and modify adapter interrupt sources (KVM_DEV_FLIC_ADAPTER_*) +- modify AIS (adapter-interruption-suppression) mode state (KVM_DEV_FLIC_AISM) Groups: KVM_DEV_FLIC_ENQUEUE @@ -107,6 +108,25 @@ struct kvm_s390_io_adapter_req { release a userspace page for the translated address specified in addr 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 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 |