Subject: [PATCH 4/6] KVM: PPC: Book3S HV P9: Split !nested case out from guest entry

From: Nicholas Piggin <[email-masked]>
Date: Thu, 3 Mar 2022 15:33:13 +1000

The differences between nested and !nested will become larger in
later changes so split them out for readability.

Signed-off-by: Nicholas Piggin <[email-masked]>
---
 arch/powerpc/kvm/book3s_hv.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index a0b674d3a2da..0289d076c0a8 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4034,6 +4034,8 @@ static int kvmhv_vcpu_entry_p9_nested(struct kvm_vcpu *vcpu, u64 time_limit, uns
 static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 			 unsigned long lpcr, u64 *tb)
 {
+	struct kvm *kvm = vcpu->kvm;
+	struct kvm_nested_guest *nested = vcpu->arch.nested;
 	u64 next_timer;
 	int trap;
 
@@ -4053,23 +4055,30 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 		trap = kvmhv_vcpu_entry_p9_nested(vcpu, time_limit, lpcr, tb);
 
 		/* H_CEDE has to be handled now, not later */
-		if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
+		if (trap == BOOK3S_INTERRUPT_SYSCALL && !nested &&
 		    kvmppc_get_gpr(vcpu, 3) == H_CEDE) {
 			kvmppc_cede(vcpu);
 			kvmppc_set_gpr(vcpu, 3, 0);
 			trap = 0;
 		}
 
-	} else {
-		struct kvm *kvm = vcpu->kvm;
+	} else if (nested) {
+		kvmppc_xive_push_vcpu(vcpu);
 
+		__this_cpu_write(cpu_in_guest, kvm);
+		trap = kvmhv_vcpu_entry_p9(vcpu, time_limit, lpcr, tb);
+		__this_cpu_write(cpu_in_guest, NULL);
+
+		kvmppc_xive_pull_vcpu(vcpu);
+
+	} else {
 		kvmppc_xive_push_vcpu(vcpu);
 
 		__this_cpu_write(cpu_in_guest, kvm);
 		trap = kvmhv_vcpu_entry_p9(vcpu, time_limit, lpcr, tb);
 		__this_cpu_write(cpu_in_guest, NULL);
 
-		if (trap == BOOK3S_INTERRUPT_SYSCALL && !vcpu->arch.nested &&
+		if (trap == BOOK3S_INTERRUPT_SYSCALL &&
 		    !(vcpu->arch.shregs.msr & MSR_PR)) {
 			unsigned long req = kvmppc_get_gpr(vcpu, 3);
 
-- 
2.23.0