Commit bbe9abbd authored by Nitin A Kamble's avatar Nitin A Kamble Committed by Avi Kivity
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KVM: x86 emulator: imlpement jump conditional relative 



Implement emulation of instruction:
    jump conditional rel
    opcodes: 0x0f 0x80 - 0x0f 0x8f

Signed-off-by: default avatarNitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 7de75248

drivers/kvm/x86_emulate.c

+60 −1
Original line number Diff line number Diff line
@@ -188,7 +188,10 @@ static u16 twobyte_table[256] = { 
	/* 0x70 - 0x7F */

	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

	/* 0x80 - 0x8F */

	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,

	/* 0x90 - 0x9F */

	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

	/* 0xA0 - 0xA7 */
@@ -479,6 +482,41 @@ static int read_descriptor(struct x86_emulate_ctxt *ctxt, 
	return rc;

}



static int test_cc(unsigned int condition, unsigned int flags)

{

	int rc = 0;



	switch ((condition & 15) >> 1) {

	case 0: /* o */

		rc |= (flags & EFLG_OF);

		break;

	case 1: /* b/c/nae */

		rc |= (flags & EFLG_CF);

		break;

	case 2: /* z/e */

		rc |= (flags & EFLG_ZF);

		break;

	case 3: /* be/na */

		rc |= (flags & (EFLG_CF|EFLG_ZF));

		break;

	case 4: /* s */

		rc |= (flags & EFLG_SF);

		break;

	case 5: /* p/pe */

		rc |= (flags & EFLG_PF);

		break;

	case 7: /* le/ng */

		rc |= (flags & EFLG_ZF);

		/* fall through */

	case 6: /* l/nge */

		rc |= (!(flags & EFLG_SF) != !(flags & EFLG_OF));

		break;

	}



	/* Odd condition identifiers (lsb == 1) have inverted sense. */

	return (!!rc ^ (condition & 1));

}



int

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

{
@@ -1486,6 +1524,27 @@ x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 
		}

		rc = X86EMUL_CONTINUE;

		break;

	case 0x80 ... 0x8f: /* jnz rel, etc*/ {

		long int rel;



		switch (op_bytes) {

		case 2:

			rel = insn_fetch(s16, 2, _eip);

			break;

		case 4:

			rel = insn_fetch(s32, 4, _eip);

			break;

		case 8:

			rel = insn_fetch(s64, 8, _eip);

			break;

		default:

			DPRINTF("jnz: Invalid op_bytes\n");

			goto cannot_emulate;

		}

		if (test_cc(b, _eflags))

			JMP_REL(rel);

		break;

	}

	case 0xc7:		/* Grp9 (cmpxchg8b) */

		{

			u64 old, new;