KVM: PPC: Book3S HV: Refactor HFSCR emulation for KVM guests

Refactor HFSCR emulation for KVM guests when they exit out with
H_FAC_UNAVAIL to use a switch case instead of checking all "cause"
values, since the "cause" values are mutually exclusive; and this is
better expressed with a switch case.

Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240716115206.70210-1-gautam@linux.ibm.com

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 8f7d7e37bc8c603fa87f9927029dc62d6abf0a58..0c06d2a59861188d13f8548a0d4bd8bdfd06f5d3 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1922,14 +1922,22 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu,
 
                r = EMULATE_FAIL;
                if (cpu_has_feature(CPU_FTR_ARCH_300)) {
-                       if (cause == FSCR_MSGP_LG)
+                       switch (cause) {
+                       case FSCR_MSGP_LG:
                                r = kvmppc_emulate_doorbell_instr(vcpu);
-                       if (cause == FSCR_PM_LG)
+                               break;
+                       case FSCR_PM_LG:
                                r = kvmppc_pmu_unavailable(vcpu);
-                       if (cause == FSCR_EBB_LG)
+                               break;
+                       case FSCR_EBB_LG:
                                r = kvmppc_ebb_unavailable(vcpu);
-                       if (cause == FSCR_TM_LG)
+                               break;
+                       case FSCR_TM_LG:
                                r = kvmppc_tm_unavailable(vcpu);
+                               break;
+                       default:
+                               break;
+                       }
                }
                if (r == EMULATE_FAIL) {
                        kvmppc_core_queue_program(vcpu, SRR1_PROGILL |