[PATCH v2] KVM: PPC: Book3S HV: Refactor HFSCR emulation for KVM guests

From: Gautam Menghani
Date: Tue Jul 16 2024 - 07:57:28 EST


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@xxxxxxxxxxxxx>
---
V1 -> V2:
1. Reword changelog to point out mutual exclusivity of HFSCR bits.
2. Reword commit message to match other commits in book3s_hv.c

arch/powerpc/kvm/book3s_hv.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index daaf7faf21a5..50797b0611a2 100644
--- 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 |
--
2.45.1