KVM: s390: SIGP SET PREFIX cleanup

This patch cleanes up the the SIGP SET PREFIX code.

A SIGP SET PREFIX irq may only be injected if the target vcpu is
stopped. Let's move the checking code into the injection code and
return -EBUSY if the target vcpu is not stopped.

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

1 files changed, 11 insertions, 19 deletions

diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index a25185444c70..8ae449576574 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -176,41 +176,33 @@ static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
                              u32 address, u64 *reg)
 {
-        struct kvm_s390_local_interrupt *li;
+        struct kvm_s390_irq irq = {
+                .type = KVM_S390_SIGP_SET_PREFIX,
+                .u.prefix.address = address & 0x7fffe000u,
+        };
         int rc;
 
-        li = &dst_vcpu->arch.local_int;
-
         /*
          * Make sure the new value is valid memory. We only need to check the
          * first page, since address is 8k aligned and memory pieces are always
          * at least 1MB aligned and have at least a size of 1MB.
          */
-        address &= 0x7fffe000u;
-        if (kvm_is_error_gpa(vcpu->kvm, address)) {
+        if (kvm_is_error_gpa(vcpu->kvm, irq.u.prefix.address)) {
                 *reg &= 0xffffffff00000000UL;
                 *reg |= SIGP_STATUS_INVALID_PARAMETER;
                 return SIGP_CC_STATUS_STORED;
         }
 
-        spin_lock(&li->lock);
-        /* cpu must be in stopped state */
-        if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
+        rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
+        if (rc == -EBUSY) {
                 *reg &= 0xffffffff00000000UL;
                 *reg |= SIGP_STATUS_INCORRECT_STATE;
-                rc = SIGP_CC_STATUS_STORED;
-                goto out_li;
+                return SIGP_CC_STATUS_STORED;
+        } else if (rc == 0) {
+                VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x",
+                           dst_vcpu->vcpu_id, irq.u.prefix.address);
         }
 
-        li->irq.prefix.address = address;
-        set_bit(IRQ_PEND_SET_PREFIX, &li->pending_irqs);
-        kvm_s390_vcpu_wakeup(dst_vcpu);
-        rc = SIGP_CC_ORDER_CODE_ACCEPTED;
-
-        VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", dst_vcpu->vcpu_id,
-                   address);
-out_li:
-        spin_unlock(&li->lock);
         return rc;
 }