[v2,07/10] KVM: PPC: reimplement LOAD_FP/STORE_FP instruction mmio emulation with analyse_intr() input

Message ID 1525674016-6703-8-git-send-email-wei.guo.simon@gmail.com
State Superseded
Headers show
Series
  • KVM: PPC: reimplement mmio emulation with analyse_instr()
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Commit Message

Simon Guo May 7, 2018, 6:20 a.m.
From: Simon Guo <wei.guo.simon@gmail.com>

This patch reimplements LOAD_FP/STORE_FP instruction MMIO emulation with
analyse_intr() input. It utilizes the FPCONV/UPDATE properties exported by
analyse_instr() and invokes kvmppc_handle_load(s)/kvmppc_handle_store()
accordingly.

For FP store MMIO emulation, the FP regs need to be flushed firstly so
that the right FP reg vals can be read from vcpu->arch.fpr, which will
be stored into MMIO data.

Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
---
 arch/powerpc/kvm/emulate_loadstore.c | 197 +++++++----------------------------
 1 file changed, 40 insertions(+), 157 deletions(-)

Comments

Paul Mackerras May 16, 2018, 11:52 p.m. | #1
On Mon, May 07, 2018 at 02:20:13PM +0800, wei.guo.simon@gmail.com wrote:
> From: Simon Guo <wei.guo.simon@gmail.com>
> 
> This patch reimplements LOAD_FP/STORE_FP instruction MMIO emulation with
> analyse_intr() input. It utilizes the FPCONV/UPDATE properties exported by
> analyse_instr() and invokes kvmppc_handle_load(s)/kvmppc_handle_store()
> accordingly.
> 
> For FP store MMIO emulation, the FP regs need to be flushed firstly so
> that the right FP reg vals can be read from vcpu->arch.fpr, which will
> be stored into MMIO data.
> 
> Suggested-by: Paul Mackerras <paulus@ozlabs.org>
> Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>

One comment below, otherwise looks good...

>  arch/powerpc/kvm/emulate_loadstore.c | 197 +++++++----------------------------
>  1 file changed, 40 insertions(+), 157 deletions(-)
> 
> diff --git a/arch/powerpc/kvm/emulate_loadstore.c b/arch/powerpc/kvm/emulate_loadstore.c
> index 2a91845..5a6571c 100644
> --- a/arch/powerpc/kvm/emulate_loadstore.c
> +++ b/arch/powerpc/kvm/emulate_loadstore.c
> @@ -138,6 +138,22 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
>  
>  			break;
>  		}
> +#ifdef CONFIG_PPC_FPU
> +		case LOAD_FP:
> +			if (kvmppc_check_fp_disabled(vcpu))
> +				return EMULATE_DONE;
> +
> +			if (op.type & FPCONV)
> +				vcpu->arch.mmio_sp64_extend = 1;
> +
> +			emulated = kvmppc_handle_load(run, vcpu,
> +					KVM_MMIO_REG_FPR|op.reg, size, 1);

You need to check the SIGNEXT flag and call kvmppc_handle_loads if it
is set, because of the lfiwax case:

> -		case OP_31_XOP_LFIWAX:
> -			if (kvmppc_check_fp_disabled(vcpu))
> -				return EMULATE_DONE;
> -			emulated = kvmppc_handle_loads(run, vcpu,
> -				KVM_MMIO_REG_FPR|rt, 4, 1);
> -			break;

Paul.
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Simon Guo May 17, 2018, 2:26 a.m. | #2
On Thu, May 17, 2018 at 09:52:07AM +1000, Paul Mackerras wrote:
> On Mon, May 07, 2018 at 02:20:13PM +0800, wei.guo.simon@gmail.com wrote:
> > From: Simon Guo <wei.guo.simon@gmail.com>
> > 
> > This patch reimplements LOAD_FP/STORE_FP instruction MMIO emulation with
> > analyse_intr() input. It utilizes the FPCONV/UPDATE properties exported by
> > analyse_instr() and invokes kvmppc_handle_load(s)/kvmppc_handle_store()
> > accordingly.
> > 
> > For FP store MMIO emulation, the FP regs need to be flushed firstly so
> > that the right FP reg vals can be read from vcpu->arch.fpr, which will
> > be stored into MMIO data.
> > 
> > Suggested-by: Paul Mackerras <paulus@ozlabs.org>
> > Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
> 
> One comment below, otherwise looks good...
> 
> >  arch/powerpc/kvm/emulate_loadstore.c | 197 +++++++----------------------------
> >  1 file changed, 40 insertions(+), 157 deletions(-)
> > 
> > diff --git a/arch/powerpc/kvm/emulate_loadstore.c b/arch/powerpc/kvm/emulate_loadstore.c
> > index 2a91845..5a6571c 100644
> > --- a/arch/powerpc/kvm/emulate_loadstore.c
> > +++ b/arch/powerpc/kvm/emulate_loadstore.c
> > @@ -138,6 +138,22 @@ int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
> >  
> >  			break;
> >  		}
> > +#ifdef CONFIG_PPC_FPU
> > +		case LOAD_FP:
> > +			if (kvmppc_check_fp_disabled(vcpu))
> > +				return EMULATE_DONE;
> > +
> > +			if (op.type & FPCONV)
> > +				vcpu->arch.mmio_sp64_extend = 1;
> > +
> > +			emulated = kvmppc_handle_load(run, vcpu,
> > +					KVM_MMIO_REG_FPR|op.reg, size, 1);
> 
> You need to check the SIGNEXT flag and call kvmppc_handle_loads if it
> is set, because of the lfiwax case:
> 
> > -		case OP_31_XOP_LFIWAX:
> > -			if (kvmppc_check_fp_disabled(vcpu))
> > -				return EMULATE_DONE;
> > -			emulated = kvmppc_handle_loads(run, vcpu,
> > -				KVM_MMIO_REG_FPR|rt, 4, 1);
> > -			break;

Yes. I need to handle that. Thanks for point it out.

BR,
 - Simon
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Patch

diff --git a/arch/powerpc/kvm/emulate_loadstore.c b/arch/powerpc/kvm/emulate_loadstore.c
index 2a91845..5a6571c 100644
--- a/arch/powerpc/kvm/emulate_loadstore.c
+++ b/arch/powerpc/kvm/emulate_loadstore.c
@@ -138,6 +138,22 @@  int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
 
 			break;
 		}
+#ifdef CONFIG_PPC_FPU
+		case LOAD_FP:
+			if (kvmppc_check_fp_disabled(vcpu))
+				return EMULATE_DONE;
+
+			if (op.type & FPCONV)
+				vcpu->arch.mmio_sp64_extend = 1;
+
+			emulated = kvmppc_handle_load(run, vcpu,
+					KVM_MMIO_REG_FPR|op.reg, size, 1);
+
+			if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
+				kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
+
+			break;
+#endif
 		case STORE:
 			/* if need byte reverse, op.val has been reversed by
 			 * analyse_instr().
@@ -149,6 +165,30 @@  int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
 				kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
 
 			break;
+#ifdef CONFIG_PPC_FPU
+		case STORE_FP:
+			if (kvmppc_check_fp_disabled(vcpu))
+				return EMULATE_DONE;
+
+			/* The FP registers need to be flushed so that
+			 * kvmppc_handle_store() can read actual FP vals
+			 * from vcpu->arch.
+			 */
+			if (vcpu->kvm->arch.kvm_ops->giveup_ext)
+				vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
+						MSR_FP);
+
+			if (op.type & FPCONV)
+				vcpu->arch.mmio_sp64_extend = 1;
+
+			emulated = kvmppc_handle_store(run, vcpu,
+					VCPU_FPR(vcpu, op.reg), size, 1);
+
+			if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
+				kvmppc_set_gpr(vcpu, op.update_reg, op.ea);
+
+			break;
+#endif
 		case CACHEOP:
 			/* Do nothing. The guest is performing dcbi because
 			 * hardware DMA is not snooped by the dcache, but
@@ -170,93 +210,6 @@  int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
 	switch (get_op(inst)) {
 	case 31:
 		switch (get_xop(inst)) {
-#ifdef CONFIG_PPC_FPU
-		case OP_31_XOP_LFSX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			vcpu->arch.mmio_sp64_extend = 1;
-			emulated = kvmppc_handle_load(run, vcpu,
-				KVM_MMIO_REG_FPR|rt, 4, 1);
-			break;
-
-		case OP_31_XOP_LFSUX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			vcpu->arch.mmio_sp64_extend = 1;
-			emulated = kvmppc_handle_load(run, vcpu,
-				KVM_MMIO_REG_FPR|rt, 4, 1);
-			kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-			break;
-
-		case OP_31_XOP_LFDX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			emulated = kvmppc_handle_load(run, vcpu,
-				KVM_MMIO_REG_FPR|rt, 8, 1);
-			break;
-
-		case OP_31_XOP_LFDUX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			emulated = kvmppc_handle_load(run, vcpu,
-				KVM_MMIO_REG_FPR|rt, 8, 1);
-			kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-			break;
-
-		case OP_31_XOP_LFIWAX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			emulated = kvmppc_handle_loads(run, vcpu,
-				KVM_MMIO_REG_FPR|rt, 4, 1);
-			break;
-
-		case OP_31_XOP_LFIWZX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			emulated = kvmppc_handle_load(run, vcpu,
-				KVM_MMIO_REG_FPR|rt, 4, 1);
-			break;
-
-		case OP_31_XOP_STFSX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			vcpu->arch.mmio_sp64_extend = 1;
-			emulated = kvmppc_handle_store(run, vcpu,
-				VCPU_FPR(vcpu, rs), 4, 1);
-			break;
-
-		case OP_31_XOP_STFSUX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			vcpu->arch.mmio_sp64_extend = 1;
-			emulated = kvmppc_handle_store(run, vcpu,
-				VCPU_FPR(vcpu, rs), 4, 1);
-			kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-			break;
-
-		case OP_31_XOP_STFDX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			emulated = kvmppc_handle_store(run, vcpu,
-				VCPU_FPR(vcpu, rs), 8, 1);
-			break;
-
-		case OP_31_XOP_STFDUX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			emulated = kvmppc_handle_store(run, vcpu,
-				VCPU_FPR(vcpu, rs), 8, 1);
-			kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-			break;
-
-		case OP_31_XOP_STFIWX:
-			if (kvmppc_check_fp_disabled(vcpu))
-				return EMULATE_DONE;
-			emulated = kvmppc_handle_store(run, vcpu,
-				VCPU_FPR(vcpu, rs), 4, 1);
-			break;
-#endif
-
 #ifdef CONFIG_VSX
 		case OP_31_XOP_LXSDX:
 			if (kvmppc_check_vsx_disabled(vcpu))
@@ -421,76 +374,6 @@  int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
 		}
 		break;
 
-#ifdef CONFIG_PPC_FPU
-	case OP_STFS:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		vcpu->arch.mmio_sp64_extend = 1;
-		emulated = kvmppc_handle_store(run, vcpu,
-			VCPU_FPR(vcpu, rs),
-			4, 1);
-		break;
-
-	case OP_STFSU:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		vcpu->arch.mmio_sp64_extend = 1;
-		emulated = kvmppc_handle_store(run, vcpu,
-			VCPU_FPR(vcpu, rs),
-			4, 1);
-		kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-		break;
-
-	case OP_STFD:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		emulated = kvmppc_handle_store(run, vcpu,
-			VCPU_FPR(vcpu, rs),
-	                               8, 1);
-		break;
-
-	case OP_STFDU:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		emulated = kvmppc_handle_store(run, vcpu,
-			VCPU_FPR(vcpu, rs),
-	                               8, 1);
-		kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-		break;
-
-	case OP_LFS:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		vcpu->arch.mmio_sp64_extend = 1;
-		emulated = kvmppc_handle_load(run, vcpu,
-			KVM_MMIO_REG_FPR|rt, 4, 1);
-		break;
-
-	case OP_LFSU:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		vcpu->arch.mmio_sp64_extend = 1;
-		emulated = kvmppc_handle_load(run, vcpu,
-			KVM_MMIO_REG_FPR|rt, 4, 1);
-		kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-		break;
-
-	case OP_LFD:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		emulated = kvmppc_handle_load(run, vcpu,
-			KVM_MMIO_REG_FPR|rt, 8, 1);
-		break;
-
-	case OP_LFDU:
-		if (kvmppc_check_fp_disabled(vcpu))
-			return EMULATE_DONE;
-		emulated = kvmppc_handle_load(run, vcpu,
-			KVM_MMIO_REG_FPR|rt, 8, 1);
-		kvmppc_set_gpr(vcpu, ra, vcpu->arch.vaddr_accessed);
-		break;
-#endif
-
 	default:
 		emulated = EMULATE_FAIL;
 		break;