Commit 8b4caf66 authored by Laurent Vivier's avatar Laurent Vivier Committed by Avi Kivity
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KVM: x86 emulator: move all decoding process to function x86_decode_insn() 



Split the decoding process into a new function x86_decode_insn().

Signed-off-by: default avatarLaurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent e4e03ded

drivers/kvm/x86_emulate.c

+53 −24
Original line number Diff line number Diff line
@@ -517,20 +517,16 @@ static int test_cc(unsigned int condition, unsigned int flags) 
}



int

x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)

x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)

{

	struct decode_cache *c = &ctxt->decode;

	u8 sib, rex_prefix = 0;

	unsigned int i;

	int rc = 0;

	unsigned long cr2 = ctxt->cr2;

	int mode = ctxt->mode;

	int index_reg = 0, base_reg = 0, scale, rip_relative = 0;

	int no_wb = 0;

	u64 msr_data;



	/* Shadow copy of register state. Committed on successful emulation. */

	unsigned long _eflags = ctxt->eflags;



	memset(c, 0, sizeof(struct decode_cache));

	c->eip = ctxt->vcpu->rip;
@@ -622,8 +618,10 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		}



		/* Unrecognised? */

		if (c->d == 0)

			goto cannot_emulate;

		if (c->d == 0) {

			DPRINTF("Cannot emulate %02x\n", c->b);

			return -1;

		}

	}



	/* ModRM and SIB bytes. */
@@ -776,7 +774,6 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		}

		if (c->ad_bytes != 8)

			c->modrm_ea = (u32)c->modrm_ea;

		cr2 = c->modrm_ea;

	modrm_done:

		;

	}
@@ -838,13 +835,6 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
			break;

		}

		c->src.type = OP_MEM;

		c->src.ptr = (unsigned long *)cr2;

		c->src.val = 0;

		if ((rc = ops->read_emulated((unsigned long)c->src.ptr,

					   &c->src.val,

					   c->src.bytes, ctxt->vcpu)) != 0)

			goto done;

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

		break;

	case SrcImm:

		c->src.type = OP_IMM;
@@ -877,7 +867,7 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
	switch (c->d & DstMask) {

	case ImplicitOps:

		/* Special instructions do their own operand decoding. */

		goto special_insn;

		return 0;

	case DstReg:

		c->dst.type = OP_REG;

		if ((c->d & ByteOp)
@@ -905,14 +895,54 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		}

		break;

	case DstMem:

		c->dst.type = OP_MEM;

		c->dst.ptr = (unsigned long *)cr2;

		c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;

		c->dst.val = 0;

		if ((c->d & ModRM) && c->modrm_mod == 3) {

			c->dst.type = OP_REG;

			break;

		}

		c->dst.type = OP_MEM;

		break;

	}



done:

	return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0;

}



int

x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)

{

	unsigned long cr2 = ctxt->cr2;

	int no_wb = 0;

	u64 msr_data;

	unsigned long _eflags = ctxt->eflags;

	struct decode_cache *c = &ctxt->decode;

	int rc;



	rc = x86_decode_insn(ctxt, ops);

	if (rc)

		return rc;



	if ((c->d & ModRM) && (c->modrm_mod != 3))

		cr2 = c->modrm_ea;



	if (c->src.type == OP_MEM) {

		c->src.ptr = (unsigned long *)cr2;

		c->src.val = 0;

		if ((rc = ops->read_emulated((unsigned long)c->src.ptr,

					     &c->src.val,

					     c->src.bytes,

					     ctxt->vcpu)) != 0)

			goto done;

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

	}



	if ((c->d & DstMask) == ImplicitOps)

		goto special_insn;





	if (c->dst.type == OP_MEM) {

		c->dst.ptr = (unsigned long *)cr2;

		c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;

		c->dst.val = 0;

		if (c->d & BitOp) {

			unsigned long mask = ~(c->dst.bytes * 8 - 1);
@@ -925,7 +955,6 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
					   &c->dst.val,

					  c->dst.bytes, ctxt->vcpu)) != 0))

			goto done;

		break;

	}

	c->dst.orig_val = c->dst.val;
@@ -983,7 +1012,7 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		emulate_2op_SrcV("cmp", c->src, c->dst, _eflags);

		break;

	case 0x63:		/* movsxd */

		if (mode != X86EMUL_MODE_PROT64)

		if (ctxt->mode != X86EMUL_MODE_PROT64)

			goto cannot_emulate;

		c->dst.val = (s32) c->src.val;

		break;
@@ -1041,7 +1070,7 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		break;

	case 0x8f:		/* pop (sole member of Grp1a) */

		/* 64-bit mode: POP always pops a 64-bit operand. */

		if (mode == X86EMUL_MODE_PROT64)

		if (ctxt->mode == X86EMUL_MODE_PROT64)

			c->dst.bytes = 8;

		if ((rc = ops->read_std(register_address(

						   ctxt->ss_base,
@@ -1152,7 +1181,7 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
			break;

		case 6:	/* push */

			/* 64-bit mode: PUSH always pushes a 64-bit operand. */

			if (mode == X86EMUL_MODE_PROT64) {

			if (ctxt->mode == X86EMUL_MODE_PROT64) {

				c->dst.bytes = 8;

				if ((rc = ops->read_std(

						 (unsigned long)c->dst.ptr,