KVM: s390: Add support for channel I/O instructions.
Add a new capability, KVM_CAP_S390_CSS_SUPPORT, which will pass
intercepts for channel I/O instructions to userspace. Only I/O
instructions interacting with I/O interrupts need to be handled
in-kernel:
- TEST PENDING INTERRUPTION (tpi) dequeues and stores pending
interrupts entirely in-kernel.
- TEST SUBCHANNEL (tsch) dequeues pending interrupts in-kernel
and exits via KVM_EXIT_S390_TSCH to userspace for subchannel-
related processing.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index b3b4748..9a12835 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -709,6 +709,43 @@
return 0;
}
+struct kvm_s390_interrupt_info *kvm_s390_get_io_int(struct kvm *kvm,
+ u64 cr6, u64 schid)
+{
+ struct kvm_s390_float_interrupt *fi;
+ struct kvm_s390_interrupt_info *inti, *iter;
+
+ if ((!schid && !cr6) || (schid && cr6))
+ return NULL;
+ mutex_lock(&kvm->lock);
+ fi = &kvm->arch.float_int;
+ spin_lock(&fi->lock);
+ inti = NULL;
+ list_for_each_entry(iter, &fi->list, list) {
+ if (!is_ioint(iter->type))
+ continue;
+ if (cr6 && ((cr6 & iter->io.io_int_word) == 0))
+ continue;
+ if (schid) {
+ if (((schid & 0x00000000ffff0000) >> 16) !=
+ iter->io.subchannel_id)
+ continue;
+ if ((schid & 0x000000000000ffff) !=
+ iter->io.subchannel_nr)
+ continue;
+ }
+ inti = iter;
+ break;
+ }
+ if (inti)
+ list_del_init(&inti->list);
+ if (list_empty(&fi->list))
+ atomic_set(&fi->active, 0);
+ spin_unlock(&fi->lock);
+ mutex_unlock(&kvm->lock);
+ return inti;
+}
+
int kvm_s390_inject_vm(struct kvm *kvm,
struct kvm_s390_interrupt *s390int)
{