arch/powerpc/kvm/emulate_loadstore.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  *
  * Copyright IBM Corp. 2007
  * Copyright 2011 Freescale Semiconductor, Inc.
  *
  * Authors: Hollis Blanchard <hollisb@us.ibm.com>
  */

 #include <linux/jiffies.h>
 #include <linux/hrtimer.h>
 #include <linux/types.h>
 #include <linux/string.h>
 #include <linux/kvm_host.h>
 #include <linux/clockchips.h>

 #include <asm/reg.h>
 #include <asm/time.h>
 #include <asm/byteorder.h>
 #include <asm/kvm_ppc.h>
 #include <asm/disassemble.h>
 #include <asm/ppc-opcode.h>
 #include <asm/sstep.h>
 #include "timing.h"
 #include "trace.h"

 #ifdef CONFIG_PPC_FPU
 static bool kvmppc_check_fp_disabled(struct kvm_vcpu *vcpu)
 {
 	if (!(kvmppc_get_msr(vcpu) & MSR_FP)) {
 		kvmppc_core_queue_fpunavail(vcpu);
 		return true;
 	}

 	return false;
 }
 #endif /* CONFIG_PPC_FPU */

 #ifdef CONFIG_VSX
 static bool kvmppc_check_vsx_disabled(struct kvm_vcpu *vcpu)
 {
 	if (!(kvmppc_get_msr(vcpu) & MSR_VSX)) {
 		kvmppc_core_queue_vsx_unavail(vcpu);
 		return true;
 	}

 	return false;
 }
 #endif /* CONFIG_VSX */

 #ifdef CONFIG_ALTIVEC
 static bool kvmppc_check_altivec_disabled(struct kvm_vcpu *vcpu)
 {
 	if (!(kvmppc_get_msr(vcpu) & MSR_VEC)) {
 		kvmppc_core_queue_vec_unavail(vcpu);
 		return true;
 	}

 	return false;
 }
 #endif /* CONFIG_ALTIVEC */

 /*
  * XXX to do:
  * lfiwax, lfiwzx
  * vector loads and stores
  *
  * Instructions that trap when used on cache-inhibited mappings
  * are not emulated here: multiple and string instructions,
  * lq/stq, and the load-reserve/store-conditional instructions.
  */
 int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
 {
 	struct kvm_run *run = vcpu->run;
 	u32 inst;
 	enum emulation_result emulated = EMULATE_FAIL;
 	int advance = 1;
 	struct instruction_op op;

 	/* this default type might be overwritten by subcategories */
 	kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS);

 	emulated = kvmppc_get_last_inst(vcpu, INST_GENERIC, &inst);
 	if (emulated != EMULATE_DONE)
 		return emulated;

 	vcpu->arch.mmio_vsx_copy_nums = 0;
 	vcpu->arch.mmio_vsx_offset = 0;
 	vcpu->arch.mmio_copy_type = KVMPPC_VSX_COPY_NONE;
 	vcpu->arch.mmio_sp64_extend = 0;
 	vcpu->arch.mmio_sign_extend = 0;
 	vcpu->arch.mmio_vmx_copy_nums = 0;
 	vcpu->arch.mmio_vmx_offset = 0;
 	vcpu->arch.mmio_host_swabbed = 0;

 	emulated = EMULATE_FAIL;
 	vcpu->arch.regs.msr = vcpu->arch.shared->msr;
 	if (analyse_instr(&op, &vcpu->arch.regs, inst) == 0) {
 		int type = op.type & INSTR_TYPE_MASK;
 		int size = GETSIZE(op.type);

 		switch (type) {
 		case LOAD:  {
 			int instr_byte_swap = op.type & BYTEREV;

 			if (op.type & SIGNEXT)
 				emulated = kvmppc_handle_loads(run, vcpu,
 						op.reg, size, !instr_byte_swap);
 			else
 				emulated = kvmppc_handle_load(run, vcpu,
 						op.reg, size, !instr_byte_swap);

 			if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
 				kvmppc_set_gpr(vcpu, op.update_reg, op.ea);

 			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;

 			if (op.type & SIGNEXT)
 				emulated = kvmppc_handle_loads(run, vcpu,
 					     KVM_MMIO_REG_FPR|op.reg, size, 1);
 			else
 				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
 #ifdef CONFIG_ALTIVEC
 		case LOAD_VMX:
 			if (kvmppc_check_altivec_disabled(vcpu))
 				return EMULATE_DONE;

 			/* Hardware enforces alignment of VMX accesses */
 			vcpu->arch.vaddr_accessed &= ~((unsigned long)size - 1);
 			vcpu->arch.paddr_accessed &= ~((unsigned long)size - 1);

 			if (size == 16) { /* lvx */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_DWORD;
 			} else if (size == 4) { /* lvewx  */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_WORD;
 			} else if (size == 2) { /* lvehx  */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_HWORD;
 			} else if (size == 1) { /* lvebx  */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_BYTE;
 			} else
 				break;

 			vcpu->arch.mmio_vmx_offset =
 				(vcpu->arch.vaddr_accessed & 0xf)/size;

 			if (size == 16) {
 				vcpu->arch.mmio_vmx_copy_nums = 2;
 				emulated = kvmppc_handle_vmx_load(run,
 						vcpu, KVM_MMIO_REG_VMX|op.reg,
 						8, 1);
 			} else {
 				vcpu->arch.mmio_vmx_copy_nums = 1;
 				emulated = kvmppc_handle_vmx_load(run, vcpu,
 						KVM_MMIO_REG_VMX|op.reg,
 						size, 1);
 			}
 			break;
 #endif
 #ifdef CONFIG_VSX
 		case LOAD_VSX: {
 			int io_size_each;

 			if (op.vsx_flags & VSX_CHECK_VEC) {
 				if (kvmppc_check_altivec_disabled(vcpu))
 					return EMULATE_DONE;
 			} else {
 				if (kvmppc_check_vsx_disabled(vcpu))
 					return EMULATE_DONE;
 			}

 			if (op.vsx_flags & VSX_FPCONV)
 				vcpu->arch.mmio_sp64_extend = 1;

 			if (op.element_size == 8)  {
 				if (op.vsx_flags & VSX_SPLAT)
 					vcpu->arch.mmio_copy_type =
 						KVMPPC_VSX_COPY_DWORD_LOAD_DUMP;
 				else
 					vcpu->arch.mmio_copy_type =
 						KVMPPC_VSX_COPY_DWORD;
 			} else if (op.element_size == 4) {
 				if (op.vsx_flags & VSX_SPLAT)
 					vcpu->arch.mmio_copy_type =
 						KVMPPC_VSX_COPY_WORD_LOAD_DUMP;
 				else
 					vcpu->arch.mmio_copy_type =
 						KVMPPC_VSX_COPY_WORD;
 			} else
 				break;

 			if (size < op.element_size) {
 				/* precision convert case: lxsspx, etc */
 				vcpu->arch.mmio_vsx_copy_nums = 1;
 				io_size_each = size;
 			} else { /* lxvw4x, lxvd2x, etc */
 				vcpu->arch.mmio_vsx_copy_nums =
 					size/op.element_size;
 				io_size_each = op.element_size;
 			}

 			emulated = kvmppc_handle_vsx_load(run, vcpu,
 					KVM_MMIO_REG_VSX|op.reg, io_size_each,
 					1, op.type & SIGNEXT);
 			break;
 		}
 #endif
 		case STORE:
 			/* if need byte reverse, op.val has been reversed by
 			 * analyse_instr().
 			 */
 			emulated = kvmppc_handle_store(run, vcpu, op.val,
 					size, 1);

 			if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
 				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
 #ifdef CONFIG_ALTIVEC
 		case STORE_VMX:
 			if (kvmppc_check_altivec_disabled(vcpu))
 				return EMULATE_DONE;

 			/* Hardware enforces alignment of VMX accesses. */
 			vcpu->arch.vaddr_accessed &= ~((unsigned long)size - 1);
 			vcpu->arch.paddr_accessed &= ~((unsigned long)size - 1);

 			if (vcpu->kvm->arch.kvm_ops->giveup_ext)
 				vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
 						MSR_VEC);
 			if (size == 16) { /* stvx */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_DWORD;
 			} else if (size == 4) { /* stvewx  */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_WORD;
 			} else if (size == 2) { /* stvehx  */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_HWORD;
 			} else if (size == 1) { /* stvebx  */
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VMX_COPY_BYTE;
 			} else
 				break;

 			vcpu->arch.mmio_vmx_offset =
 				(vcpu->arch.vaddr_accessed & 0xf)/size;

 			if (size == 16) {
 				vcpu->arch.mmio_vmx_copy_nums = 2;
 				emulated = kvmppc_handle_vmx_store(run,
 						vcpu, op.reg, 8, 1);
 			} else {
 				vcpu->arch.mmio_vmx_copy_nums = 1;
 				emulated = kvmppc_handle_vmx_store(run,
 						vcpu, op.reg, size, 1);
 			}

 			break;
 #endif
 #ifdef CONFIG_VSX
 		case STORE_VSX: {
 			int io_size_each;

 			if (op.vsx_flags & VSX_CHECK_VEC) {
 				if (kvmppc_check_altivec_disabled(vcpu))
 					return EMULATE_DONE;
 			} else {
 				if (kvmppc_check_vsx_disabled(vcpu))
 					return EMULATE_DONE;
 			}

 			if (vcpu->kvm->arch.kvm_ops->giveup_ext)
 				vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
 						MSR_VSX);

 			if (op.vsx_flags & VSX_FPCONV)
 				vcpu->arch.mmio_sp64_extend = 1;

 			if (op.element_size == 8)
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VSX_COPY_DWORD;
 			else if (op.element_size == 4)
 				vcpu->arch.mmio_copy_type =
 						KVMPPC_VSX_COPY_WORD;
 			else
 				break;

 			if (size < op.element_size) {
 				/* precise conversion case, like stxsspx */
 				vcpu->arch.mmio_vsx_copy_nums = 1;
 				io_size_each = size;
 			} else { /* stxvw4x, stxvd2x, etc */
 				vcpu->arch.mmio_vsx_copy_nums =
 						size/op.element_size;
 				io_size_each = op.element_size;
 			}

 			emulated = kvmppc_handle_vsx_store(run, vcpu,
 					op.reg, io_size_each, 1);
 			break;
 		}
 #endif
 		case CACHEOP:
 			/* Do nothing. The guest is performing dcbi because
 			 * hardware DMA is not snooped by the dcache, but
 			 * emulated DMA either goes through the dcache as
 			 * normal writes, or the host kernel has handled dcache
 			 * coherence.
 			 */
 			emulated = EMULATE_DONE;
 			break;
 		default:
 			break;
 		}
 	}

 	if (emulated == EMULATE_FAIL) {
 		advance = 0;
 		kvmppc_core_queue_program(vcpu, 0);
 	}

 	trace_kvm_ppc_instr(inst, kvmppc_get_pc(vcpu), emulated);

 	/* Advance past emulated instruction. */
 	if (advance)
 		kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) + 4);

 	return emulated;
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	*
	* Copyright IBM Corp. 2007
	* Copyright 2011 Freescale Semiconductor, Inc.
	*
	* Authors: Hollis Blanchard <hollisb@us.ibm.com>
	*/

	#include <linux/jiffies.h>
	#include <linux/hrtimer.h>
	#include <linux/types.h>
	#include <linux/string.h>
	#include <linux/kvm_host.h>
	#include <linux/clockchips.h>

	#include <asm/reg.h>
	#include <asm/time.h>
	#include <asm/byteorder.h>
	#include <asm/kvm_ppc.h>
	#include <asm/disassemble.h>
	#include <asm/ppc-opcode.h>
	#include <asm/sstep.h>
	#include "timing.h"
	#include "trace.h"

	#ifdef CONFIG_PPC_FPU
	static bool kvmppc_check_fp_disabled(struct kvm_vcpu *vcpu)
	{
	if (!(kvmppc_get_msr(vcpu) & MSR_FP)) {
	kvmppc_core_queue_fpunavail(vcpu);
	return true;
	}

	return false;
	}
	#endif /* CONFIG_PPC_FPU */

	#ifdef CONFIG_VSX
	static bool kvmppc_check_vsx_disabled(struct kvm_vcpu *vcpu)
	{
	if (!(kvmppc_get_msr(vcpu) & MSR_VSX)) {
	kvmppc_core_queue_vsx_unavail(vcpu);
	return true;
	}

	return false;
	}
	#endif /* CONFIG_VSX */

	#ifdef CONFIG_ALTIVEC
	static bool kvmppc_check_altivec_disabled(struct kvm_vcpu *vcpu)
	{
	if (!(kvmppc_get_msr(vcpu) & MSR_VEC)) {
	kvmppc_core_queue_vec_unavail(vcpu);
	return true;
	}

	return false;
	}
	#endif /* CONFIG_ALTIVEC */

	/*
	* XXX to do:
	* lfiwax, lfiwzx
	* vector loads and stores
	*
	* Instructions that trap when used on cache-inhibited mappings
	* are not emulated here: multiple and string instructions,
	* lq/stq, and the load-reserve/store-conditional instructions.
	*/
	int kvmppc_emulate_loadstore(struct kvm_vcpu *vcpu)
	{
	struct kvm_run *run = vcpu->run;
	u32 inst;
	enum emulation_result emulated = EMULATE_FAIL;
	int advance = 1;
	struct instruction_op op;

	/* this default type might be overwritten by subcategories */
	kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS);

	emulated = kvmppc_get_last_inst(vcpu, INST_GENERIC, &inst);
	if (emulated != EMULATE_DONE)
	return emulated;

	vcpu->arch.mmio_vsx_copy_nums = 0;
	vcpu->arch.mmio_vsx_offset = 0;
	vcpu->arch.mmio_copy_type = KVMPPC_VSX_COPY_NONE;
	vcpu->arch.mmio_sp64_extend = 0;
	vcpu->arch.mmio_sign_extend = 0;
	vcpu->arch.mmio_vmx_copy_nums = 0;
	vcpu->arch.mmio_vmx_offset = 0;
	vcpu->arch.mmio_host_swabbed = 0;

	emulated = EMULATE_FAIL;
	vcpu->arch.regs.msr = vcpu->arch.shared->msr;
	if (analyse_instr(&op, &vcpu->arch.regs, inst) == 0) {
	int type = op.type & INSTR_TYPE_MASK;
	int size = GETSIZE(op.type);

	switch (type) {
	case LOAD: {
	int instr_byte_swap = op.type & BYTEREV;

	if (op.type & SIGNEXT)
	emulated = kvmppc_handle_loads(run, vcpu,
	op.reg, size, !instr_byte_swap);
	else
	emulated = kvmppc_handle_load(run, vcpu,
	op.reg, size, !instr_byte_swap);

	if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
	kvmppc_set_gpr(vcpu, op.update_reg, op.ea);

	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;

	if (op.type & SIGNEXT)
	emulated = kvmppc_handle_loads(run, vcpu,
	KVM_MMIO_REG_FPR\|op.reg, size, 1);
	else
	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
	#ifdef CONFIG_ALTIVEC
	case LOAD_VMX:
	if (kvmppc_check_altivec_disabled(vcpu))
	return EMULATE_DONE;

	/* Hardware enforces alignment of VMX accesses */
	vcpu->arch.vaddr_accessed &= ~((unsigned long)size - 1);
	vcpu->arch.paddr_accessed &= ~((unsigned long)size - 1);

	if (size == 16) { /* lvx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_DWORD;
	} else if (size == 4) { /* lvewx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_WORD;
	} else if (size == 2) { /* lvehx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_HWORD;
	} else if (size == 1) { /* lvebx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_BYTE;
	} else
	break;

	vcpu->arch.mmio_vmx_offset =
	(vcpu->arch.vaddr_accessed & 0xf)/size;

	if (size == 16) {
	vcpu->arch.mmio_vmx_copy_nums = 2;
	emulated = kvmppc_handle_vmx_load(run,
	vcpu, KVM_MMIO_REG_VMX\|op.reg,
	8, 1);
	} else {
	vcpu->arch.mmio_vmx_copy_nums = 1;
	emulated = kvmppc_handle_vmx_load(run, vcpu,
	KVM_MMIO_REG_VMX\|op.reg,
	size, 1);
	}
	break;
	#endif
	#ifdef CONFIG_VSX
	case LOAD_VSX: {
	int io_size_each;

	if (op.vsx_flags & VSX_CHECK_VEC) {
	if (kvmppc_check_altivec_disabled(vcpu))
	return EMULATE_DONE;
	} else {
	if (kvmppc_check_vsx_disabled(vcpu))
	return EMULATE_DONE;
	}

	if (op.vsx_flags & VSX_FPCONV)
	vcpu->arch.mmio_sp64_extend = 1;

	if (op.element_size == 8) {
	if (op.vsx_flags & VSX_SPLAT)
	vcpu->arch.mmio_copy_type =
	KVMPPC_VSX_COPY_DWORD_LOAD_DUMP;
	else
	vcpu->arch.mmio_copy_type =
	KVMPPC_VSX_COPY_DWORD;
	} else if (op.element_size == 4) {
	if (op.vsx_flags & VSX_SPLAT)
	vcpu->arch.mmio_copy_type =
	KVMPPC_VSX_COPY_WORD_LOAD_DUMP;
	else
	vcpu->arch.mmio_copy_type =
	KVMPPC_VSX_COPY_WORD;
	} else
	break;

	if (size < op.element_size) {
	/* precision convert case: lxsspx, etc */
	vcpu->arch.mmio_vsx_copy_nums = 1;
	io_size_each = size;
	} else { /* lxvw4x, lxvd2x, etc */
	vcpu->arch.mmio_vsx_copy_nums =
	size/op.element_size;
	io_size_each = op.element_size;
	}

	emulated = kvmppc_handle_vsx_load(run, vcpu,
	KVM_MMIO_REG_VSX\|op.reg, io_size_each,
	1, op.type & SIGNEXT);
	break;
	}
	#endif
	case STORE:
	/* if need byte reverse, op.val has been reversed by
	* analyse_instr().
	*/
	emulated = kvmppc_handle_store(run, vcpu, op.val,
	size, 1);

	if ((op.type & UPDATE) && (emulated != EMULATE_FAIL))
	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
	#ifdef CONFIG_ALTIVEC
	case STORE_VMX:
	if (kvmppc_check_altivec_disabled(vcpu))
	return EMULATE_DONE;

	/* Hardware enforces alignment of VMX accesses. */
	vcpu->arch.vaddr_accessed &= ~((unsigned long)size - 1);
	vcpu->arch.paddr_accessed &= ~((unsigned long)size - 1);

	if (vcpu->kvm->arch.kvm_ops->giveup_ext)
	vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
	MSR_VEC);
	if (size == 16) { /* stvx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_DWORD;
	} else if (size == 4) { /* stvewx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_WORD;
	} else if (size == 2) { /* stvehx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_HWORD;
	} else if (size == 1) { /* stvebx */
	vcpu->arch.mmio_copy_type =
	KVMPPC_VMX_COPY_BYTE;
	} else
	break;

	vcpu->arch.mmio_vmx_offset =
	(vcpu->arch.vaddr_accessed & 0xf)/size;

	if (size == 16) {
	vcpu->arch.mmio_vmx_copy_nums = 2;
	emulated = kvmppc_handle_vmx_store(run,
	vcpu, op.reg, 8, 1);
	} else {
	vcpu->arch.mmio_vmx_copy_nums = 1;
	emulated = kvmppc_handle_vmx_store(run,
	vcpu, op.reg, size, 1);
	}

	break;
	#endif
	#ifdef CONFIG_VSX
	case STORE_VSX: {
	int io_size_each;

	if (op.vsx_flags & VSX_CHECK_VEC) {
	if (kvmppc_check_altivec_disabled(vcpu))
	return EMULATE_DONE;
	} else {
	if (kvmppc_check_vsx_disabled(vcpu))
	return EMULATE_DONE;
	}

	if (vcpu->kvm->arch.kvm_ops->giveup_ext)
	vcpu->kvm->arch.kvm_ops->giveup_ext(vcpu,
	MSR_VSX);

	if (op.vsx_flags & VSX_FPCONV)
	vcpu->arch.mmio_sp64_extend = 1;

	if (op.element_size == 8)
	vcpu->arch.mmio_copy_type =
	KVMPPC_VSX_COPY_DWORD;
	else if (op.element_size == 4)
	vcpu->arch.mmio_copy_type =
	KVMPPC_VSX_COPY_WORD;
	else
	break;

	if (size < op.element_size) {
	/* precise conversion case, like stxsspx */
	vcpu->arch.mmio_vsx_copy_nums = 1;
	io_size_each = size;
	} else { /* stxvw4x, stxvd2x, etc */
	vcpu->arch.mmio_vsx_copy_nums =
	size/op.element_size;
	io_size_each = op.element_size;
	}

	emulated = kvmppc_handle_vsx_store(run, vcpu,
	op.reg, io_size_each, 1);
	break;
	}
	#endif
	case CACHEOP:
	/* Do nothing. The guest is performing dcbi because
	* hardware DMA is not snooped by the dcache, but
	* emulated DMA either goes through the dcache as
	* normal writes, or the host kernel has handled dcache
	* coherence.
	*/
	emulated = EMULATE_DONE;
	break;
	default:
	break;
	}
	}

	if (emulated == EMULATE_FAIL) {
	advance = 0;
	kvmppc_core_queue_program(vcpu, 0);
	}

	trace_kvm_ppc_instr(inst, kvmppc_get_pc(vcpu), emulated);

	/* Advance past emulated instruction. */
	if (advance)
	kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) + 4);

	return emulated;
	}