Commit 6de2e837 authored by Jordan Niethe's avatar Jordan Niethe Committed by Michael Ellerman
Browse files

KVM: PPC: Book3S HV: Introduce low level MSR accessor 



kvmppc_get_msr() and kvmppc_set_msr_fast() serve as accessors for the
MSR. However because the MSR is kept in the shared regs they include a
conditional check for kvmppc_shared_big_endian() and endian conversion.

Within the Book3S HV specific code there are direct reads and writes of
shregs::msr. In preparation for Nested APIv2 these accesses need to be
replaced with accessor functions so it is possible to extend their
behavior. However, using the kvmppc_get_msr() and kvmppc_set_msr_fast()
functions is undesirable because it would introduce a conditional branch
and endian conversion that is not currently present.

kvmppc_set_msr_hv() already exists, it is used for the
kvmppc_ops::set_msr callback.

Introduce a low level accessor __kvmppc_{s,g}et_msr_hv() that simply
gets and sets shregs::msr. This will be extend for Nested APIv2 support.

Signed-off-by: default avatarJordan Niethe <jniethe5@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230914030600.16993-8-jniethe5@gmail.com
parent ebc88ea7

arch/powerpc/kvm/book3s_64_mmu_hv.c

+3 −2
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
#include <asm/pte-walk.h>



#include "book3s.h"

#include "book3s_hv.h"

#include "trace_hv.h"



//#define DEBUG_RESIZE_HPT	1
@@ -347,7 +348,7 @@ static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, 
	unsigned long v, orig_v, gr;

	__be64 *hptep;

	long int index;

	int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR);

	int virtmode = __kvmppc_get_msr_hv(vcpu) & (data ? MSR_DR : MSR_IR);



	if (kvm_is_radix(vcpu->kvm))

		return kvmppc_mmu_radix_xlate(vcpu, eaddr, gpte, data, iswrite);
@@ -385,7 +386,7 @@ static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, 


	/* Get PP bits and key for permission check */

	pp = gr & (HPTE_R_PP0 | HPTE_R_PP);

	key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;

	key = (__kvmppc_get_msr_hv(vcpu) & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;

	key &= slb_v;



	/* Calculate permissions */

arch/powerpc/kvm/book3s_hv.c

+17 −17
Original line number Diff line number Diff line
@@ -1374,7 +1374,7 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu) 
 */

static void kvmppc_cede(struct kvm_vcpu *vcpu)

{

	vcpu->arch.shregs.msr |= MSR_EE;

	__kvmppc_set_msr_hv(vcpu, __kvmppc_get_msr_hv(vcpu) | MSR_EE);

	vcpu->arch.ceded = 1;

	smp_mb();

	if (vcpu->arch.prodded) {
@@ -1589,7 +1589,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
	 * That can happen due to a bug, or due to a machine check

	 * occurring at just the wrong time.

	 */

	if (vcpu->arch.shregs.msr & MSR_HV) {

	if (__kvmppc_get_msr_hv(vcpu) & MSR_HV) {

		printk(KERN_EMERG "KVM trap in HV mode!\n");

		printk(KERN_EMERG "trap=0x%x | pc=0x%lx | msr=0x%llx\n",

			vcpu->arch.trap, kvmppc_get_pc(vcpu),
@@ -1640,7 +1640,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
		 * so that it knows that the machine check occurred.

		 */

		if (!vcpu->kvm->arch.fwnmi_enabled) {

			ulong flags = (vcpu->arch.shregs.msr & 0x083c0000) |

			ulong flags = (__kvmppc_get_msr_hv(vcpu) & 0x083c0000) |

					(kvmppc_get_msr(vcpu) & SRR1_PREFIXED);

			kvmppc_core_queue_machine_check(vcpu, flags);

			r = RESUME_GUEST;
@@ -1670,7 +1670,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
		 * as a result of a hypervisor emulation interrupt

		 * (e40) getting turned into a 700 by BML RTAS.

		 */

		flags = (vcpu->arch.shregs.msr & 0x1f0000ull) |

		flags = (__kvmppc_get_msr_hv(vcpu) & 0x1f0000ull) |

			(kvmppc_get_msr(vcpu) & SRR1_PREFIXED);

		kvmppc_core_queue_program(vcpu, flags);

		r = RESUME_GUEST;
@@ -1680,7 +1680,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
	{

		int i;



		if (unlikely(vcpu->arch.shregs.msr & MSR_PR)) {

		if (unlikely(__kvmppc_get_msr_hv(vcpu) & MSR_PR)) {

			/*

			 * Guest userspace executed sc 1. This can only be

			 * reached by the P9 path because the old path
@@ -1758,7 +1758,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
			break;

		}



		if (!(vcpu->arch.shregs.msr & MSR_DR))

		if (!(__kvmppc_get_msr_hv(vcpu) & MSR_DR))

			vsid = vcpu->kvm->arch.vrma_slb_v;

		else

			vsid = vcpu->arch.fault_gpa;
@@ -1782,7 +1782,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
		long err;



		vcpu->arch.fault_dar = kvmppc_get_pc(vcpu);

		vcpu->arch.fault_dsisr = vcpu->arch.shregs.msr &

		vcpu->arch.fault_dsisr = __kvmppc_get_msr_hv(vcpu) &

			DSISR_SRR1_MATCH_64S;

		if (kvm_is_radix(vcpu->kvm) || !cpu_has_feature(CPU_FTR_ARCH_300)) {

			/*
@@ -1791,7 +1791,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
			 * hash fault handling below is v3 only (it uses ASDR

			 * via fault_gpa).

			 */

			if (vcpu->arch.shregs.msr & HSRR1_HISI_WRITE)

			if (__kvmppc_get_msr_hv(vcpu) & HSRR1_HISI_WRITE)

				vcpu->arch.fault_dsisr |= DSISR_ISSTORE;

			r = RESUME_PAGE_FAULT;

			break;
@@ -1805,7 +1805,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
			break;

		}



		if (!(vcpu->arch.shregs.msr & MSR_IR))

		if (!(__kvmppc_get_msr_hv(vcpu) & MSR_IR))

			vsid = vcpu->kvm->arch.vrma_slb_v;

		else

			vsid = vcpu->arch.fault_gpa;
@@ -1895,7 +1895,7 @@ static int kvmppc_handle_exit_hv(struct kvm_vcpu *vcpu, 
		kvmppc_dump_regs(vcpu);

		printk(KERN_EMERG "trap=0x%x | pc=0x%lx | msr=0x%llx\n",

			vcpu->arch.trap, kvmppc_get_pc(vcpu),

			vcpu->arch.shregs.msr);

			__kvmppc_get_msr_hv(vcpu));

		run->hw.hardware_exit_reason = vcpu->arch.trap;

		r = RESUME_HOST;

		break;
@@ -1919,11 +1919,11 @@ static int kvmppc_handle_nested_exit(struct kvm_vcpu *vcpu) 
	 * That can happen due to a bug, or due to a machine check

	 * occurring at just the wrong time.

	 */

	if (vcpu->arch.shregs.msr & MSR_HV) {

	if (__kvmppc_get_msr_hv(vcpu) & MSR_HV) {

		pr_emerg("KVM trap in HV mode while nested!\n");

		pr_emerg("trap=0x%x | pc=0x%lx | msr=0x%llx\n",

			 vcpu->arch.trap, kvmppc_get_pc(vcpu),

			 vcpu->arch.shregs.msr);

			 __kvmppc_get_msr_hv(vcpu));

		kvmppc_dump_regs(vcpu);

		return RESUME_HOST;

	}
@@ -1980,7 +1980,7 @@ static int kvmppc_handle_nested_exit(struct kvm_vcpu *vcpu) 
		vcpu->arch.fault_dar = kvmppc_get_pc(vcpu);

		vcpu->arch.fault_dsisr = kvmppc_get_msr(vcpu) &

					 DSISR_SRR1_MATCH_64S;

		if (vcpu->arch.shregs.msr & HSRR1_HISI_WRITE)

		if (__kvmppc_get_msr_hv(vcpu) & HSRR1_HISI_WRITE)

			vcpu->arch.fault_dsisr |= DSISR_ISSTORE;

		srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);

		r = kvmhv_nested_page_fault(vcpu);
@@ -2940,7 +2940,7 @@ static int kvmppc_core_vcpu_create_hv(struct kvm_vcpu *vcpu) 
	spin_lock_init(&vcpu->arch.vpa_update_lock);

	spin_lock_init(&vcpu->arch.tbacct_lock);

	vcpu->arch.busy_preempt = TB_NIL;

	vcpu->arch.shregs.msr = MSR_ME;

	__kvmppc_set_msr_hv(vcpu, MSR_ME);

	vcpu->arch.intr_msr = MSR_SF | MSR_ME;



	/*
@@ -4188,7 +4188,7 @@ static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit, 
		__this_cpu_write(cpu_in_guest, NULL);



		if (trap == BOOK3S_INTERRUPT_SYSCALL &&

		    !(vcpu->arch.shregs.msr & MSR_PR)) {

		    !(__kvmppc_get_msr_hv(vcpu) & MSR_PR)) {

			unsigned long req = kvmppc_get_gpr(vcpu, 3);



			/*
@@ -4667,7 +4667,7 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit, 


	if (!nested) {

		kvmppc_core_prepare_to_enter(vcpu);

		if (vcpu->arch.shregs.msr & MSR_EE) {

		if (__kvmppc_get_msr_hv(vcpu) & MSR_EE) {

			if (xive_interrupt_pending(vcpu))

				kvmppc_inject_interrupt_hv(vcpu,

						BOOK3S_INTERRUPT_EXTERNAL, 0);
@@ -4880,7 +4880,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_vcpu *vcpu) 
		if (run->exit_reason == KVM_EXIT_PAPR_HCALL) {

			accumulate_time(vcpu, &vcpu->arch.hcall);



			if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_PR)) {

			if (WARN_ON_ONCE(__kvmppc_get_msr_hv(vcpu) & MSR_PR)) {

				/*

				 * These should have been caught reflected

				 * into the guest by now. Final sanity check:

arch/powerpc/kvm/book3s_hv.h

+10 −0
Original line number Diff line number Diff line
@@ -51,6 +51,16 @@ void accumulate_time(struct kvm_vcpu *vcpu, struct kvmhv_tb_accumulator *next); 
#define end_timing(vcpu) do {} while (0)

#endif



static inline void __kvmppc_set_msr_hv(struct kvm_vcpu *vcpu, u64 val)

{

	vcpu->arch.shregs.msr = val;

}



static inline u64 __kvmppc_get_msr_hv(struct kvm_vcpu *vcpu)

{

	return vcpu->arch.shregs.msr;

}



#define KVMPPC_BOOK3S_HV_VCPU_ACCESSOR_SET(reg, size)			\

static inline void kvmppc_set_##reg ##_hv(struct kvm_vcpu *vcpu, u##size val)	\

{									\

arch/powerpc/kvm/book3s_hv_builtin.c

+3 −2
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 


#include "book3s_xics.h"

#include "book3s_xive.h"

#include "book3s_hv.h"



/*

 * Hash page table alignment on newer cpus(CPU_FTR_ARCH_206)
@@ -514,7 +515,7 @@ void kvmppc_set_msr_hv(struct kvm_vcpu *vcpu, u64 msr) 
	 */

	if ((msr & MSR_TS_MASK) == MSR_TS_MASK)

		msr &= ~MSR_TS_MASK;

	vcpu->arch.shregs.msr = msr;

	__kvmppc_set_msr_hv(vcpu, msr);

	kvmppc_end_cede(vcpu);

}

EXPORT_SYMBOL_GPL(kvmppc_set_msr_hv);
@@ -552,7 +553,7 @@ static void inject_interrupt(struct kvm_vcpu *vcpu, int vec, u64 srr1_flags) 
	kvmppc_set_srr0(vcpu, pc);

	kvmppc_set_srr1(vcpu, (msr & SRR1_MSR_BITS) | srr1_flags);

	kvmppc_set_pc(vcpu, new_pc);

	vcpu->arch.shregs.msr = new_msr;

	__kvmppc_set_msr_hv(vcpu, new_msr);

}



void kvmppc_inject_interrupt_hv(struct kvm_vcpu *vcpu, int vec, u64 srr1_flags)