Commit e4f973ae authored by Takuya Yoshikawa's avatar Takuya Yoshikawa Committed by Avi Kivity
Browse files

KVM: x86 emulator: Use opcode::execute for XCHG(86/87) 



In addition, replace one "goto xchg" with an em_xchg() call.

Signed-off-by: default avatarTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 9f21ca59

arch/x86/kvm/emulate.c

+17 −14
Original line number Diff line number Diff line
@@ -2613,6 +2613,20 @@ static int em_test(struct x86_emulate_ctxt *ctxt) 
	return X86EMUL_CONTINUE;

}



static int em_xchg(struct x86_emulate_ctxt *ctxt)

{

	struct decode_cache *c = &ctxt->decode;



	/* Write back the register source. */

	c->src.val = c->dst.val;

	write_register_operand(&c->src);



	/* Write back the memory destination with implicit LOCK prefix. */

	c->dst.val = c->src.orig_val;

	c->lock_prefix = 1;

	return X86EMUL_CONTINUE;

}



static int em_imul(struct x86_emulate_ctxt *ctxt)

{

	struct decode_cache *c = &ctxt->decode;
@@ -3144,7 +3158,7 @@ static struct opcode opcode_table[256] = { 
	G(ByteOp | DstMem | SrcImm | ModRM | No64 | Group, group1),

	G(DstMem | SrcImmByte | ModRM | Group, group1),

	I2bv(DstMem | SrcReg | ModRM, em_test),

	D2bv(DstMem | SrcReg | ModRM | Lock),

	I2bv(DstMem | SrcReg | ModRM | Lock, em_xchg),

	/* 0x88 - 0x8F */

	I2bv(DstMem | SrcReg | ModRM | Mov, em_mov),

	I2bv(DstReg | SrcMem | ModRM | Mov, em_mov),
@@ -3882,18 +3896,6 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt) 
		if (test_cc(c->b, ctxt->eflags))

			jmp_rel(c, c->src.val);

		break;

	case 0x86 ... 0x87:	/* xchg */

	xchg:

		/* Write back the register source. */

		c->src.val = c->dst.val;

		write_register_operand(&c->src);

		/*

		 * Write back the memory destination with implicit LOCK

		 * prefix.

		 */

		c->dst.val = c->src.orig_val;

		c->lock_prefix = 1;

		break;

	case 0x8c:  /* mov r/m, sreg */

		if (c->modrm_reg > VCPU_SREG_GS) {

			rc = emulate_ud(ctxt);
@@ -3929,7 +3931,8 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt) 
	case 0x90 ... 0x97: /* nop / xchg reg, rax */

		if (c->dst.addr.reg == &c->regs[VCPU_REGS_RAX])

			break;

		goto xchg;

		rc = em_xchg(ctxt);

		break;

	case 0x98: /* cbw/cwde/cdqe */

		switch (c->op_bytes) {

		case 2: c->dst.val = (s8)c->dst.val; break;