KVM: PPC: Implement hypervisor interface

To communicate with KVM directly we need to plumb some sort of interface
between the guest and KVM. Usually those interfaces use hypercalls.

This hypercall implementation is described in the last patch of the series
in a special documentation file. Please read that for further information.

This patch implements stubs to handle KVM PPC hypercalls on the host and
guest side alike.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index cfd7fe5c3a62..5cb5f0d9381f 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -947,10 +947,10 @@ program_interrupt:
                 break;
         }
         case BOOK3S_INTERRUPT_SYSCALL:
-                // XXX make user settable
                 if (vcpu->arch.osi_enabled &&
                     (((u32)kvmppc_get_gpr(vcpu, 3)) == OSI_SC_MAGIC_R3) &&
                     (((u32)kvmppc_get_gpr(vcpu, 4)) == OSI_SC_MAGIC_R4)) {
+                        /* MOL hypercalls */
                         u64 *gprs = run->osi.gprs;
                         int i;
 
@@ -959,8 +959,13 @@ program_interrupt:
                                 gprs[i] = kvmppc_get_gpr(vcpu, i);
                         vcpu->arch.osi_needed = 1;
                         r = RESUME_HOST_NV;
-
+                } else if (!(vcpu->arch.shared->msr & MSR_PR) &&
+                    (((u32)kvmppc_get_gpr(vcpu, 0)) == KVM_SC_MAGIC_R0)) {
+                        /* KVM PV hypercalls */
+                        kvmppc_set_gpr(vcpu, 3, kvmppc_kvm_pv(vcpu));
+                        r = RESUME_GUEST;
                 } else {
+                        /* Guest syscalls */
                         vcpu->stat.syscall_exits++;
                         kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
                         r = RESUME_GUEST;