From 6d28f789bf81540d4069342b1a28bfd41dab38a3 Mon Sep 17 00:00:00 2001 From: Halil Pasic Date: Mon, 25 Jan 2016 19:10:40 +0100 Subject: KVM: s390: add clear I/O irq operation for FLIC Introduce a FLIC operation for clearing I/O interrupts for a subchannel. Rationale: According to the platform specification, pending I/O interruption requests have to be revoked in certain situations. For instance, according to the Principles of Operation (page 17-27), a subchannel put into the installed parameters initialized state is in the same state as after an I/O system reset (just parameters possibly changed). This implies that any I/O interrupts for that subchannel are no longer pending (as I/O system resets clear I/O interrupts). Therefore, we need an interface to clear pending I/O interrupts. Signed-off-by: Halil Pasic Reviewed-by: Cornelia Huck Reviewed-by: Christian Borntraeger Signed-off-by: Christian Borntraeger Signed-off-by: Cornelia Huck --- Documentation/virtual/kvm/devices/s390_flic.txt | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation/virtual') diff --git a/Documentation/virtual/kvm/devices/s390_flic.txt b/Documentation/virtual/kvm/devices/s390_flic.txt index 646f47470f98..8478de1c0192 100644 --- a/Documentation/virtual/kvm/devices/s390_flic.txt +++ b/Documentation/virtual/kvm/devices/s390_flic.txt @@ -11,6 +11,7 @@ FLIC provides support to - add interrupts (KVM_DEV_FLIC_ENQUEUE) - inspect currently pending interrupts (KVM_FLIC_GET_ALL_IRQS) - purge all pending floating interrupts (KVM_DEV_FLIC_CLEAR_IRQS) +- 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_*) @@ -40,6 +41,11 @@ Groups: Simply deletes all elements from the list of currently pending floating interrupts. No interrupts are injected into the guest. + KVM_DEV_FLIC_CLEAR_IO_IRQ + Deletes one (if any) I/O interrupt for a subchannel identified by the + subsystem identification word passed via the buffer specified by + attr->addr (address) and attr->attr (length). + KVM_DEV_FLIC_APF_ENABLE Enables async page faults for the guest. So in case of a major page fault the host is allowed to handle this async and continues the guest. -- cgit v1.2.3