KVM: s390: handle pending local interrupts via bitmap

This patch adapts handling of local interrupts to be more compliant with
the z/Architecture Principles of Operation and introduces a data
structure
which allows more efficient handling of interrupts.

* get rid of li->active flag, use bitmap instead
* Keep interrupts in a bitmap instead of a list
* Deliver interrupts in the order of their priority as defined in the
  PoP
* Use a second bitmap for sigp emergency requests, as a CPU can have
  one request pending from every other CPU in the system.

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

arch/s390/include/asm/kvm_host.h

@@ -398,8 +398,6 @@ struct kvm_s390_irq_payload {
 
 struct kvm_s390_local_interrupt {
 	spinlock_t lock;
-	struct list_head list;
-	atomic_t active;
 	struct kvm_s390_float_interrupt *float_int;
 	wait_queue_head_t *wq;
 	atomic_t *cpuflags;

arch/s390/kvm/intercept.c

@@ -257,7 +257,7 @@ static int handle_instruction_and_prog(struct kvm_vcpu *vcpu)
 static int handle_external_interrupt(struct kvm_vcpu *vcpu)
 {
 	u16 eic = vcpu->arch.sie_block->eic;
-	struct kvm_s390_interrupt irq;
+	struct kvm_s390_irq irq;
 	psw_t newpsw;
 	int rc;
 
@@ -282,7 +282,7 @@ static int handle_external_interrupt(struct kvm_vcpu *vcpu)
 		if (kvm_s390_si_ext_call_pending(vcpu))
 			return 0;
 		irq.type = KVM_S390_INT_EXTERNAL_CALL;
-		irq.parm = vcpu->arch.sie_block->extcpuaddr;
+		irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr;
 		break;
 	default:
 		return -EOPNOTSUPP;