Commit f09ed83e authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: x86 emulator: move memop, memopp into emulation context 



Simplifies further generalization of decode.

Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 3329ece1

arch/x86/include/asm/kvm_emulate.h

+2 −0
Original line number Diff line number Diff line
@@ -275,6 +275,8 @@ struct x86_emulate_ctxt { 
	unsigned long _eip;

	/* Fields above regs are cleared together. */

	unsigned long regs[NR_VCPU_REGS];

	struct operand memop;

	struct operand *memopp;

	struct fetch_cache fetch;

	struct read_cache io_read;

	struct read_cache mem_read;

arch/x86/kvm/emulate.c

+17 −17
Original line number Diff line number Diff line
@@ -3323,8 +3323,9 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) 
	int def_op_bytes, def_ad_bytes, goffset, simd_prefix;

	bool op_prefix = false;

	struct opcode opcode;

	struct operand memop = { .type = OP_NONE }, *memopp = NULL;



	ctxt->memop.type = OP_NONE;

	ctxt->memopp = NULL;

	ctxt->_eip = ctxt->eip;

	ctxt->fetch.start = ctxt->_eip;

	ctxt->fetch.end = ctxt->fetch.start + insn_len;
@@ -3482,21 +3483,21 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) 


	/* ModRM and SIB bytes. */

	if (ctxt->d & ModRM) {

		rc = decode_modrm(ctxt, &memop);

		rc = decode_modrm(ctxt, &ctxt->memop);

		if (!ctxt->has_seg_override)

			set_seg_override(ctxt, ctxt->modrm_seg);

	} else if (ctxt->d & MemAbs)

		rc = decode_abs(ctxt, &memop);

		rc = decode_abs(ctxt, &ctxt->memop);

	if (rc != X86EMUL_CONTINUE)

		goto done;



	if (!ctxt->has_seg_override)

		set_seg_override(ctxt, VCPU_SREG_DS);



	memop.addr.mem.seg = seg_override(ctxt);

	ctxt->memop.addr.mem.seg = seg_override(ctxt);



	if (memop.type == OP_MEM && ctxt->ad_bytes != 8)

		memop.addr.mem.ea = (u32)memop.addr.mem.ea;

	if (ctxt->memop.type == OP_MEM && ctxt->ad_bytes != 8)

		ctxt->memop.addr.mem.ea = (u32)ctxt->memop.addr.mem.ea;



	/*

	 * Decode and fetch the source operand: register, memory
@@ -3509,17 +3510,16 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) 
		decode_register_operand(ctxt, &ctxt->src, 0);

		break;

	case SrcMem16:

		memop.bytes = 2;

		ctxt->memop.bytes = 2;

		goto srcmem_common;

	case SrcMem32:

		memop.bytes = 4;

		ctxt->memop.bytes = 4;

		goto srcmem_common;

	case SrcMem:

		memop.bytes = (ctxt->d & ByteOp) ? 1 :

							   ctxt->op_bytes;

		ctxt->memop.bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;

	srcmem_common:

		ctxt->src = memop;

		memopp = &ctxt->src;

		ctxt->src = ctxt->memop;

		ctxt->memopp = &ctxt->src;

		break;

	case SrcImmU16:

		rc = decode_imm(ctxt, &ctxt->src, 2, false);
@@ -3561,7 +3561,7 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) 
		insn_fetch_arr(ctxt->src.valptr, ctxt->src.bytes, ctxt);

		break;

	case SrcMemFAddr:

		memop.bytes = ctxt->op_bytes + 2;

		ctxt->memop.bytes = ctxt->op_bytes + 2;

		goto srcmem_common;

		break;

	case SrcDX:
@@ -3615,8 +3615,8 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) 
		break;

	case DstMem:

	case DstMem64:

		ctxt->dst = memop;

		memopp = &ctxt->dst;

		ctxt->dst = ctxt->memop;

		ctxt->memopp = &ctxt->dst;

		if ((ctxt->d & DstMask) == DstMem64)

			ctxt->dst.bytes = 8;

		else
@@ -3654,8 +3654,8 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) 
	}



done:

	if (memopp && memopp->type == OP_MEM && ctxt->rip_relative)

		memopp->addr.mem.ea += ctxt->_eip;

	if (ctxt->memopp && ctxt->memopp->type == OP_MEM && ctxt->rip_relative)

		ctxt->memopp->addr.mem.ea += ctxt->_eip;



	return (rc != X86EMUL_CONTINUE) ? EMULATION_FAILED : EMULATION_OK;

}