+++ /dev/null
-/******************************************************************************
- * x86_emulate.c
- *
- * Generic x86 (32-bit and 64-bit) instruction decoder and emulator.
- *
- * Copyright (c) 2005 Keir Fraser
- *
- * Linux coding style, mod r/m decoder, segment base fixes, real-mode
- * privileged instructions:
- *
- * Copyright (C) 2006 Qumranet
- *
- * Avi Kivity <avi@qumranet.com>
- * Yaniv Kamay <yaniv@qumranet.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * From: xen-unstable 10676:af9809f51f81a3c43f276f00c81a52ef558afda4
- */
-
-#ifndef __KERNEL__
-#include <stdio.h>
-#include <stdint.h>
-#include <public/xen.h>
-#define DPRINTF(_f, _a ...) printf(_f , ## _a)
-#else
-#include "kvm.h"
-#include "x86.h"
-#define DPRINTF(x...) do {} while (0)
-#endif
-#include "x86_emulate.h"
-#include <linux/module.h>
-
-/*
- * Opcode effective-address decode tables.
- * Note that we only emulate instructions that have at least one memory
- * operand (excluding implicit stack references). We assume that stack
- * references and instruction fetches will never occur in special memory
- * areas that require emulation. So, for example, 'mov <imm>,<reg>' need
- * not be handled.
- */
-
-/* Operand sizes: 8-bit operands or specified/overridden size. */
-#define ByteOp (1<<0) /* 8-bit operands. */
-/* Destination operand type. */
-#define ImplicitOps (1<<1) /* Implicit in opcode. No generic decode. */
-#define DstReg (2<<1) /* Register operand. */
-#define DstMem (3<<1) /* Memory operand. */
-#define DstMask (3<<1)
-/* Source operand type. */
-#define SrcNone (0<<3) /* No source operand. */
-#define SrcImplicit (0<<3) /* Source operand is implicit in the opcode. */
-#define SrcReg (1<<3) /* Register operand. */
-#define SrcMem (2<<3) /* Memory operand. */
-#define SrcMem16 (3<<3) /* Memory operand (16-bit). */
-#define SrcMem32 (4<<3) /* Memory operand (32-bit). */
-#define SrcImm (5<<3) /* Immediate operand. */
-#define SrcImmByte (6<<3) /* 8-bit sign-extended immediate operand. */
-#define SrcMask (7<<3)
-/* Generic ModRM decode. */
-#define ModRM (1<<6)
-/* Destination is only written; never read. */
-#define Mov (1<<7)
-#define BitOp (1<<8)
-#define MemAbs (1<<9) /* Memory operand is absolute displacement */
-#define String (1<<10) /* String instruction (rep capable) */
-#define Stack (1<<11) /* Stack instruction (push/pop) */
-
-static u16 opcode_table[256] = {
- /* 0x00 - 0x07 */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- 0, 0, 0, 0,
- /* 0x08 - 0x0F */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- 0, 0, 0, 0,
- /* 0x10 - 0x17 */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- 0, 0, 0, 0,
- /* 0x18 - 0x1F */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- 0, 0, 0, 0,
- /* 0x20 - 0x27 */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- SrcImmByte, SrcImm, 0, 0,
- /* 0x28 - 0x2F */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- 0, 0, 0, 0,
- /* 0x30 - 0x37 */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- 0, 0, 0, 0,
- /* 0x38 - 0x3F */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstReg | SrcMem | ModRM, DstReg | SrcMem | ModRM,
- 0, 0, 0, 0,
- /* 0x40 - 0x47 */
- DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg,
- /* 0x48 - 0x4F */
- DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg,
- /* 0x50 - 0x57 */
- SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, SrcReg | Stack,
- SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, SrcReg | Stack,
- /* 0x58 - 0x5F */
- DstReg | Stack, DstReg | Stack, DstReg | Stack, DstReg | Stack,
- DstReg | Stack, DstReg | Stack, DstReg | Stack, DstReg | Stack,
- /* 0x60 - 0x67 */
- 0, 0, 0, DstReg | SrcMem32 | ModRM | Mov /* movsxd (x86/64) */ ,
- 0, 0, 0, 0,
- /* 0x68 - 0x6F */
- 0, 0, ImplicitOps | Mov | Stack, 0,
- SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* insb, insw/insd */
- SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* outsb, outsw/outsd */
- /* 0x70 - 0x77 */
- ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
- ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
- /* 0x78 - 0x7F */
- ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
- ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
- /* 0x80 - 0x87 */
- ByteOp | DstMem | SrcImm | ModRM, DstMem | SrcImm | ModRM,
- ByteOp | DstMem | SrcImm | ModRM, DstMem | SrcImmByte | ModRM,
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM,
- /* 0x88 - 0x8F */
- ByteOp | DstMem | SrcReg | ModRM | Mov, DstMem | SrcReg | ModRM | Mov,
- ByteOp | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- 0, ModRM | DstReg, 0, DstMem | SrcNone | ModRM | Mov | Stack,
- /* 0x90 - 0x9F */
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, ImplicitOps | Stack, ImplicitOps | Stack, 0, 0,
- /* 0xA0 - 0xA7 */
- ByteOp | DstReg | SrcMem | Mov | MemAbs, DstReg | SrcMem | Mov | MemAbs,
- ByteOp | DstMem | SrcReg | Mov | MemAbs, DstMem | SrcReg | Mov | MemAbs,
- ByteOp | ImplicitOps | Mov | String, ImplicitOps | Mov | String,
- ByteOp | ImplicitOps | String, ImplicitOps | String,
- /* 0xA8 - 0xAF */
- 0, 0, ByteOp | ImplicitOps | Mov | String, ImplicitOps | Mov | String,
- ByteOp | ImplicitOps | Mov | String, ImplicitOps | Mov | String,
- ByteOp | ImplicitOps | String, ImplicitOps | String,
- /* 0xB0 - 0xBF */
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0xC0 - 0xC7 */
- ByteOp | DstMem | SrcImm | ModRM, DstMem | SrcImmByte | ModRM,
- 0, ImplicitOps | Stack, 0, 0,
- ByteOp | DstMem | SrcImm | ModRM | Mov, DstMem | SrcImm | ModRM | Mov,
- /* 0xC8 - 0xCF */
- 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0xD0 - 0xD7 */
- ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM,
- ByteOp | DstMem | SrcImplicit | ModRM, DstMem | SrcImplicit | ModRM,
- 0, 0, 0, 0,
- /* 0xD8 - 0xDF */
- 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0xE0 - 0xE7 */
- 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0xE8 - 0xEF */
- ImplicitOps | Stack, SrcImm|ImplicitOps, 0, SrcImmByte|ImplicitOps,
- 0, 0, 0, 0,
- /* 0xF0 - 0xF7 */
- 0, 0, 0, 0,
- ImplicitOps, ImplicitOps,
- ByteOp | DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM,
- /* 0xF8 - 0xFF */
- ImplicitOps, 0, ImplicitOps, ImplicitOps,
- 0, 0, ByteOp | DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM
-};
-
-static u16 twobyte_table[256] = {
- /* 0x00 - 0x0F */
- 0, SrcMem | ModRM | DstReg, 0, 0, 0, 0, ImplicitOps, 0,
- ImplicitOps, ImplicitOps, 0, 0, 0, ImplicitOps | ModRM, 0, 0,
- /* 0x10 - 0x1F */
- 0, 0, 0, 0, 0, 0, 0, 0, ImplicitOps | ModRM, 0, 0, 0, 0, 0, 0, 0,
- /* 0x20 - 0x2F */
- ModRM | ImplicitOps, ModRM, ModRM | ImplicitOps, ModRM, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0x30 - 0x3F */
- ImplicitOps, 0, ImplicitOps, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0x40 - 0x47 */
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- /* 0x48 - 0x4F */
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
- /* 0x50 - 0x5F */
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0x60 - 0x6F */
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0x70 - 0x7F */
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0x80 - 0x8F */
- 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 */
- 0, 0, 0, DstMem | SrcReg | ModRM | BitOp, 0, 0, 0, 0,
- /* 0xA8 - 0xAF */
- 0, 0, 0, DstMem | SrcReg | ModRM | BitOp, 0, 0, 0, 0,
- /* 0xB0 - 0xB7 */
- ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, 0,
- DstMem | SrcReg | ModRM | BitOp,
- 0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem16 | ModRM | Mov,
- /* 0xB8 - 0xBF */
- 0, 0, DstMem | SrcImmByte | ModRM, DstMem | SrcReg | ModRM | BitOp,
- 0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov,
- DstReg | SrcMem16 | ModRM | Mov,
- /* 0xC0 - 0xCF */
- 0, 0, 0, DstMem | SrcReg | ModRM | Mov, 0, 0, 0, ImplicitOps | ModRM,
- 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0xD0 - 0xDF */
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0xE0 - 0xEF */
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- /* 0xF0 - 0xFF */
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
-};
-
-/* EFLAGS bit definitions. */
-#define EFLG_OF (1<<11)
-#define EFLG_DF (1<<10)
-#define EFLG_SF (1<<7)
-#define EFLG_ZF (1<<6)
-#define EFLG_AF (1<<4)
-#define EFLG_PF (1<<2)
-#define EFLG_CF (1<<0)
-
-/*
- * Instruction emulation:
- * Most instructions are emulated directly via a fragment of inline assembly
- * code. This allows us to save/restore EFLAGS and thus very easily pick up
- * any modified flags.
- */
-
-#if defined(CONFIG_X86_64)
-#define _LO32 "k" /* force 32-bit operand */
-#define _STK "%%rsp" /* stack pointer */
-#elif defined(__i386__)
-#define _LO32 "" /* force 32-bit operand */
-#define _STK "%%esp" /* stack pointer */
-#endif
-
-/*
- * These EFLAGS bits are restored from saved value during emulation, and
- * any changes are written back to the saved value after emulation.
- */
-#define EFLAGS_MASK (EFLG_OF|EFLG_SF|EFLG_ZF|EFLG_AF|EFLG_PF|EFLG_CF)
-
-/* Before executing instruction: restore necessary bits in EFLAGS. */
-#define _PRE_EFLAGS(_sav, _msk, _tmp) \
- /* EFLAGS = (_sav & _msk) | (EFLAGS & ~_msk); _sav &= ~_msk; */ \
- "movl %"_sav",%"_LO32 _tmp"; " \
- "push %"_tmp"; " \
- "push %"_tmp"; " \
- "movl %"_msk",%"_LO32 _tmp"; " \
- "andl %"_LO32 _tmp",("_STK"); " \
- "pushf; " \
- "notl %"_LO32 _tmp"; " \
- "andl %"_LO32 _tmp",("_STK"); " \
- "andl %"_LO32 _tmp","__stringify(BITS_PER_LONG/4)"("_STK"); " \
- "pop %"_tmp"; " \
- "orl %"_LO32 _tmp",("_STK"); " \
- "popf; " \
- "pop %"_sav"; "
-
-/* After executing instruction: write-back necessary bits in EFLAGS. */
-#define _POST_EFLAGS(_sav, _msk, _tmp) \
- /* _sav |= EFLAGS & _msk; */ \
- "pushf; " \
- "pop %"_tmp"; " \
- "andl %"_msk",%"_LO32 _tmp"; " \
- "orl %"_LO32 _tmp",%"_sav"; "
-
-/* Raw emulation: instruction has two explicit operands. */
-#define __emulate_2op_nobyte(_op,_src,_dst,_eflags,_wx,_wy,_lx,_ly,_qx,_qy) \
- do { \
- unsigned long _tmp; \
- \
- switch ((_dst).bytes) { \
- case 2: \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "4", "2") \
- _op"w %"_wx"3,%1; " \
- _POST_EFLAGS("0", "4", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), \
- "=&r" (_tmp) \
- : _wy ((_src).val), "i" (EFLAGS_MASK)); \
- break; \
- case 4: \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "4", "2") \
- _op"l %"_lx"3,%1; " \
- _POST_EFLAGS("0", "4", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), \
- "=&r" (_tmp) \
- : _ly ((_src).val), "i" (EFLAGS_MASK)); \
- break; \
- case 8: \
- __emulate_2op_8byte(_op, _src, _dst, \
- _eflags, _qx, _qy); \
- break; \
- } \
- } while (0)
-
-#define __emulate_2op(_op,_src,_dst,_eflags,_bx,_by,_wx,_wy,_lx,_ly,_qx,_qy) \
- do { \
- unsigned long _tmp; \
- switch ((_dst).bytes) { \
- case 1: \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "4", "2") \
- _op"b %"_bx"3,%1; " \
- _POST_EFLAGS("0", "4", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), \
- "=&r" (_tmp) \
- : _by ((_src).val), "i" (EFLAGS_MASK)); \
- break; \
- default: \
- __emulate_2op_nobyte(_op, _src, _dst, _eflags, \
- _wx, _wy, _lx, _ly, _qx, _qy); \
- break; \
- } \
- } while (0)
-
-/* Source operand is byte-sized and may be restricted to just %cl. */
-#define emulate_2op_SrcB(_op, _src, _dst, _eflags) \
- __emulate_2op(_op, _src, _dst, _eflags, \
- "b", "c", "b", "c", "b", "c", "b", "c")
-
-/* Source operand is byte, word, long or quad sized. */
-#define emulate_2op_SrcV(_op, _src, _dst, _eflags) \
- __emulate_2op(_op, _src, _dst, _eflags, \
- "b", "q", "w", "r", _LO32, "r", "", "r")
-
-/* Source operand is word, long or quad sized. */
-#define emulate_2op_SrcV_nobyte(_op, _src, _dst, _eflags) \
- __emulate_2op_nobyte(_op, _src, _dst, _eflags, \
- "w", "r", _LO32, "r", "", "r")
-
-/* Instruction has only one explicit operand (no source operand). */
-#define emulate_1op(_op, _dst, _eflags) \
- do { \
- unsigned long _tmp; \
- \
- switch ((_dst).bytes) { \
- case 1: \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "3", "2") \
- _op"b %1; " \
- _POST_EFLAGS("0", "3", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), \
- "=&r" (_tmp) \
- : "i" (EFLAGS_MASK)); \
- break; \
- case 2: \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "3", "2") \
- _op"w %1; " \
- _POST_EFLAGS("0", "3", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), \
- "=&r" (_tmp) \
- : "i" (EFLAGS_MASK)); \
- break; \
- case 4: \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "3", "2") \
- _op"l %1; " \
- _POST_EFLAGS("0", "3", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), \
- "=&r" (_tmp) \
- : "i" (EFLAGS_MASK)); \
- break; \
- case 8: \
- __emulate_1op_8byte(_op, _dst, _eflags); \
- break; \
- } \
- } while (0)
-
-/* Emulate an instruction with quadword operands (x86/64 only). */
-#if defined(CONFIG_X86_64)
-#define __emulate_2op_8byte(_op, _src, _dst, _eflags, _qx, _qy) \
- do { \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "4", "2") \
- _op"q %"_qx"3,%1; " \
- _POST_EFLAGS("0", "4", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), "=&r" (_tmp) \
- : _qy ((_src).val), "i" (EFLAGS_MASK)); \
- } while (0)
-
-#define __emulate_1op_8byte(_op, _dst, _eflags) \
- do { \
- __asm__ __volatile__ ( \
- _PRE_EFLAGS("0", "3", "2") \
- _op"q %1; " \
- _POST_EFLAGS("0", "3", "2") \
- : "=m" (_eflags), "=m" ((_dst).val), "=&r" (_tmp) \
- : "i" (EFLAGS_MASK)); \
- } while (0)
-
-#elif defined(__i386__)
-#define __emulate_2op_8byte(_op, _src, _dst, _eflags, _qx, _qy)
-#define __emulate_1op_8byte(_op, _dst, _eflags)
-#endif /* __i386__ */
-
-/* Fetch next part of the instruction being emulated. */
-#define insn_fetch(_type, _size, _eip) \
-({ unsigned long _x; \
- rc = do_insn_fetch(ctxt, ops, (_eip), &_x, (_size)); \
- if (rc != 0) \
- goto done; \
- (_eip) += (_size); \
- (_type)_x; \
-})
-
-/* Access/update address held in a register, based on addressing mode. */
-#define address_mask(reg) \
- ((c->ad_bytes == sizeof(unsigned long)) ? \
- (reg) : ((reg) & ((1UL << (c->ad_bytes << 3)) - 1)))
-#define register_address(base, reg) \
- ((base) + address_mask(reg))
-#define register_address_increment(reg, inc) \
- do { \
- /* signed type ensures sign extension to long */ \
- int _inc = (inc); \
- if (c->ad_bytes == sizeof(unsigned long)) \
- (reg) += _inc; \
- else \
- (reg) = ((reg) & \
- ~((1UL << (c->ad_bytes << 3)) - 1)) | \
- (((reg) + _inc) & \
- ((1UL << (c->ad_bytes << 3)) - 1)); \
- } while (0)
-
-#define JMP_REL(rel) \
- do { \
- register_address_increment(c->eip, rel); \
- } while (0)
-
-static int do_fetch_insn_byte(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops,
- unsigned long linear, u8 *dest)
-{
- struct fetch_cache *fc = &ctxt->decode.fetch;
- int rc;
- int size;
-
- if (linear < fc->start || linear >= fc->end) {
- size = min(15UL, PAGE_SIZE - offset_in_page(linear));
- rc = ops->read_std(linear, fc->data, size, ctxt->vcpu);
- if (rc)
- return rc;
- fc->start = linear;
- fc->end = linear + size;
- }
- *dest = fc->data[linear - fc->start];
- return 0;
-}
-
-static int do_insn_fetch(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops,
- unsigned long eip, void *dest, unsigned size)
-{
- int rc = 0;
-
- eip += ctxt->cs_base;
- while (size--) {
- rc = do_fetch_insn_byte(ctxt, ops, eip++, dest++);
- if (rc)
- return rc;
- }
- return 0;
-}
-
-/*
- * Given the 'reg' portion of a ModRM byte, and a register block, return a
- * pointer into the block that addresses the relevant register.
- * @highbyte_regs specifies whether to decode AH,CH,DH,BH.
- */
-static void *decode_register(u8 modrm_reg, unsigned long *regs,
- int highbyte_regs)
-{
- void *p;
-
- p = ®s[modrm_reg];
- if (highbyte_regs && modrm_reg >= 4 && modrm_reg < 8)
- p = (unsigned char *)®s[modrm_reg & 3] + 1;
- return p;
-}
-
-static int read_descriptor(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops,
- void *ptr,
- u16 *size, unsigned long *address, int op_bytes)
-{
- int rc;
-
- if (op_bytes == 2)
- op_bytes = 3;
- *address = 0;
- rc = ops->read_std((unsigned long)ptr, (unsigned long *)size, 2,
- ctxt->vcpu);
- if (rc)
- return rc;
- rc = ops->read_std((unsigned long)ptr + 2, address, op_bytes,
- ctxt->vcpu);
- 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));
-}
-
-static void decode_register_operand(struct operand *op,
- struct decode_cache *c,
- int inhibit_bytereg)
-{
- unsigned reg = c->modrm_reg;
- int highbyte_regs = c->rex_prefix == 0;
-
- if (!(c->d & ModRM))
- reg = (c->b & 7) | ((c->rex_prefix & 1) << 3);
- op->type = OP_REG;
- if ((c->d & ByteOp) && !inhibit_bytereg) {
- op->ptr = decode_register(reg, c->regs, highbyte_regs);
- op->val = *(u8 *)op->ptr;
- op->bytes = 1;
- } else {
- op->ptr = decode_register(reg, c->regs, 0);
- op->bytes = c->op_bytes;
- switch (op->bytes) {
- case 2:
- op->val = *(u16 *)op->ptr;
- break;
- case 4:
- op->val = *(u32 *)op->ptr;
- break;
- case 8:
- op->val = *(u64 *) op->ptr;
- break;
- }
- }
- op->orig_val = op->val;
-}
-
-static int decode_modrm(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops)
-{
- struct decode_cache *c = &ctxt->decode;
- u8 sib;
- int index_reg = 0, base_reg = 0, scale, rip_relative = 0;
- int rc = 0;
-
- if (c->rex_prefix) {
- c->modrm_reg = (c->rex_prefix & 4) << 1; /* REX.R */
- index_reg = (c->rex_prefix & 2) << 2; /* REX.X */
- c->modrm_rm = base_reg = (c->rex_prefix & 1) << 3; /* REG.B */
- }
-
- c->modrm = insn_fetch(u8, 1, c->eip);
- c->modrm_mod |= (c->modrm & 0xc0) >> 6;
- c->modrm_reg |= (c->modrm & 0x38) >> 3;
- c->modrm_rm |= (c->modrm & 0x07);
- c->modrm_ea = 0;
- c->use_modrm_ea = 1;
-
- if (c->modrm_mod == 3) {
- c->modrm_val = *(unsigned long *)
- decode_register(c->modrm_rm, c->regs, c->d & ByteOp);
- return rc;
- }
-
- if (c->ad_bytes == 2) {
- unsigned bx = c->regs[VCPU_REGS_RBX];
- unsigned bp = c->regs[VCPU_REGS_RBP];
- unsigned si = c->regs[VCPU_REGS_RSI];
- unsigned di = c->regs[VCPU_REGS_RDI];
-
- /* 16-bit ModR/M decode. */
- switch (c->modrm_mod) {
- case 0:
- if (c->modrm_rm == 6)
- c->modrm_ea += insn_fetch(u16, 2, c->eip);
- break;
- case 1:
- c->modrm_ea += insn_fetch(s8, 1, c->eip);
- break;
- case 2:
- c->modrm_ea += insn_fetch(u16, 2, c->eip);
- break;
- }
- switch (c->modrm_rm) {
- case 0:
- c->modrm_ea += bx + si;
- break;
- case 1:
- c->modrm_ea += bx + di;
- break;
- case 2:
- c->modrm_ea += bp + si;
- break;
- case 3:
- c->modrm_ea += bp + di;
- break;
- case 4:
- c->modrm_ea += si;
- break;
- case 5:
- c->modrm_ea += di;
- break;
- case 6:
- if (c->modrm_mod != 0)
- c->modrm_ea += bp;
- break;
- case 7:
- c->modrm_ea += bx;
- break;
- }
- if (c->modrm_rm == 2 || c->modrm_rm == 3 ||
- (c->modrm_rm == 6 && c->modrm_mod != 0))
- if (!c->override_base)
- c->override_base = &ctxt->ss_base;
- c->modrm_ea = (u16)c->modrm_ea;
- } else {
- /* 32/64-bit ModR/M decode. */
- switch (c->modrm_rm) {
- case 4:
- case 12:
- sib = insn_fetch(u8, 1, c->eip);
- index_reg |= (sib >> 3) & 7;
- base_reg |= sib & 7;
- scale = sib >> 6;
-
- switch (base_reg) {
- case 5:
- if (c->modrm_mod != 0)
- c->modrm_ea += c->regs[base_reg];
- else
- c->modrm_ea +=
- insn_fetch(s32, 4, c->eip);
- break;
- default:
- c->modrm_ea += c->regs[base_reg];
- }
- switch (index_reg) {
- case 4:
- break;
- default:
- c->modrm_ea += c->regs[index_reg] << scale;
- }
- break;
- case 5:
- if (c->modrm_mod != 0)
- c->modrm_ea += c->regs[c->modrm_rm];
- else if (ctxt->mode == X86EMUL_MODE_PROT64)
- rip_relative = 1;
- break;
- default:
- c->modrm_ea += c->regs[c->modrm_rm];
- break;
- }
- switch (c->modrm_mod) {
- case 0:
- if (c->modrm_rm == 5)
- c->modrm_ea += insn_fetch(s32, 4, c->eip);
- break;
- case 1:
- c->modrm_ea += insn_fetch(s8, 1, c->eip);
- break;
- case 2:
- c->modrm_ea += insn_fetch(s32, 4, c->eip);
- break;
- }
- }
- if (rip_relative) {
- c->modrm_ea += c->eip;
- switch (c->d & SrcMask) {
- case SrcImmByte:
- c->modrm_ea += 1;
- break;
- case SrcImm:
- if (c->d & ByteOp)
- c->modrm_ea += 1;
- else
- if (c->op_bytes == 8)
- c->modrm_ea += 4;
- else
- c->modrm_ea += c->op_bytes;
- }
- }
-done:
- return rc;
-}
-
-static int decode_abs(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops)
-{
- struct decode_cache *c = &ctxt->decode;
- int rc = 0;
-
- switch (c->ad_bytes) {
- case 2:
- c->modrm_ea = insn_fetch(u16, 2, c->eip);
- break;
- case 4:
- c->modrm_ea = insn_fetch(u32, 4, c->eip);
- break;
- case 8:
- c->modrm_ea = insn_fetch(u64, 8, c->eip);
- break;
- }
-done:
- return rc;
-}
-
-int
-x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
-{
- struct decode_cache *c = &ctxt->decode;
- int rc = 0;
- int mode = ctxt->mode;
- int def_op_bytes, def_ad_bytes;
-
- /* Shadow copy of register state. Committed on successful emulation. */
-
- memset(c, 0, sizeof(struct decode_cache));
- c->eip = ctxt->vcpu->arch.rip;
- memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
-
- switch (mode) {
- case X86EMUL_MODE_REAL:
- case X86EMUL_MODE_PROT16:
- def_op_bytes = def_ad_bytes = 2;
- break;
- case X86EMUL_MODE_PROT32:
- def_op_bytes = def_ad_bytes = 4;
- break;
-#ifdef CONFIG_X86_64
- case X86EMUL_MODE_PROT64:
- def_op_bytes = 4;
- def_ad_bytes = 8;
- break;
-#endif
- default:
- return -1;
- }
-
- c->op_bytes = def_op_bytes;
- c->ad_bytes = def_ad_bytes;
-
- /* Legacy prefixes. */
- for (;;) {
- switch (c->b = insn_fetch(u8, 1, c->eip)) {
- case 0x66: /* operand-size override */
- /* switch between 2/4 bytes */
- c->op_bytes = def_op_bytes ^ 6;
- break;
- case 0x67: /* address-size override */
- if (mode == X86EMUL_MODE_PROT64)
- /* switch between 4/8 bytes */
- c->ad_bytes = def_ad_bytes ^ 12;
- else
- /* switch between 2/4 bytes */
- c->ad_bytes = def_ad_bytes ^ 6;
- break;
- case 0x2e: /* CS override */
- c->override_base = &ctxt->cs_base;
- break;
- case 0x3e: /* DS override */
- c->override_base = &ctxt->ds_base;
- break;
- case 0x26: /* ES override */
- c->override_base = &ctxt->es_base;
- break;
- case 0x64: /* FS override */
- c->override_base = &ctxt->fs_base;
- break;
- case 0x65: /* GS override */
- c->override_base = &ctxt->gs_base;
- break;
- case 0x36: /* SS override */
- c->override_base = &ctxt->ss_base;
- break;
- case 0x40 ... 0x4f: /* REX */
- if (mode != X86EMUL_MODE_PROT64)
- goto done_prefixes;
- c->rex_prefix = c->b;
- continue;
- case 0xf0: /* LOCK */
- c->lock_prefix = 1;
- break;
- case 0xf2: /* REPNE/REPNZ */
- c->rep_prefix = REPNE_PREFIX;
- break;
- case 0xf3: /* REP/REPE/REPZ */
- c->rep_prefix = REPE_PREFIX;
- break;
- default:
- goto done_prefixes;
- }
-
- /* Any legacy prefix after a REX prefix nullifies its effect. */
-
- c->rex_prefix = 0;
- }
-
-done_prefixes:
-
- /* REX prefix. */
- if (c->rex_prefix)
- if (c->rex_prefix & 8)
- c->op_bytes = 8; /* REX.W */
-
- /* Opcode byte(s). */
- c->d = opcode_table[c->b];
- if (c->d == 0) {
- /* Two-byte opcode? */
- if (c->b == 0x0f) {
- c->twobyte = 1;
- c->b = insn_fetch(u8, 1, c->eip);
- c->d = twobyte_table[c->b];
- }
-
- /* Unrecognised? */
- if (c->d == 0) {
- DPRINTF("Cannot emulate %02x\n", c->b);
- return -1;
- }
- }
-
- if (mode == X86EMUL_MODE_PROT64 && (c->d & Stack))
- c->op_bytes = 8;
-
- /* ModRM and SIB bytes. */
- if (c->d & ModRM)
- rc = decode_modrm(ctxt, ops);
- else if (c->d & MemAbs)
- rc = decode_abs(ctxt, ops);
- if (rc)
- goto done;
-
- if (!c->override_base)
- c->override_base = &ctxt->ds_base;
- if (mode == X86EMUL_MODE_PROT64 &&
- c->override_base != &ctxt->fs_base &&
- c->override_base != &ctxt->gs_base)
- c->override_base = NULL;
-
- if (c->override_base)
- c->modrm_ea += *c->override_base;
-
- if (c->ad_bytes != 8)
- c->modrm_ea = (u32)c->modrm_ea;
- /*
- * Decode and fetch the source operand: register, memory
- * or immediate.
- */
- switch (c->d & SrcMask) {
- case SrcNone:
- break;
- case SrcReg:
- decode_register_operand(&c->src, c, 0);
- break;
- case SrcMem16:
- c->src.bytes = 2;
- goto srcmem_common;
- case SrcMem32:
- c->src.bytes = 4;
- goto srcmem_common;
- case SrcMem:
- c->src.bytes = (c->d & ByteOp) ? 1 :
- c->op_bytes;
- /* Don't fetch the address for invlpg: it could be unmapped. */
- if (c->twobyte && c->b == 0x01 && c->modrm_reg == 7)
- break;
- srcmem_common:
- /*
- * For instructions with a ModR/M byte, switch to register
- * access if Mod = 3.
- */
- if ((c->d & ModRM) && c->modrm_mod == 3) {
- c->src.type = OP_REG;
- break;
- }
- c->src.type = OP_MEM;
- break;
- case SrcImm:
- c->src.type = OP_IMM;
- c->src.ptr = (unsigned long *)c->eip;
- c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
- if (c->src.bytes == 8)
- c->src.bytes = 4;
- /* NB. Immediates are sign-extended as necessary. */
- switch (c->src.bytes) {
- case 1:
- c->src.val = insn_fetch(s8, 1, c->eip);
- break;
- case 2:
- c->src.val = insn_fetch(s16, 2, c->eip);
- break;
- case 4:
- c->src.val = insn_fetch(s32, 4, c->eip);
- break;
- }
- break;
- case SrcImmByte:
- c->src.type = OP_IMM;
- c->src.ptr = (unsigned long *)c->eip;
- c->src.bytes = 1;
- c->src.val = insn_fetch(s8, 1, c->eip);
- break;
- }
-
- /* Decode and fetch the destination operand: register or memory. */
- switch (c->d & DstMask) {
- case ImplicitOps:
- /* Special instructions do their own operand decoding. */
- return 0;
- case DstReg:
- decode_register_operand(&c->dst, c,
- c->twobyte && (c->b == 0xb6 || c->b == 0xb7));
- break;
- case DstMem:
- 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;
-}
-
-static inline void emulate_push(struct x86_emulate_ctxt *ctxt)
-{
- struct decode_cache *c = &ctxt->decode;
-
- c->dst.type = OP_MEM;
- c->dst.bytes = c->op_bytes;
- c->dst.val = c->src.val;
- register_address_increment(c->regs[VCPU_REGS_RSP], -c->op_bytes);
- c->dst.ptr = (void *) register_address(ctxt->ss_base,
- c->regs[VCPU_REGS_RSP]);
-}
-
-static inline int emulate_grp1a(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops)
-{
- struct decode_cache *c = &ctxt->decode;
- int rc;
-
- rc = ops->read_std(register_address(ctxt->ss_base,
- c->regs[VCPU_REGS_RSP]),
- &c->dst.val, c->dst.bytes, ctxt->vcpu);
- if (rc != 0)
- return rc;
-
- register_address_increment(c->regs[VCPU_REGS_RSP], c->dst.bytes);
-
- return 0;
-}
-
-static inline void emulate_grp2(struct x86_emulate_ctxt *ctxt)
-{
- struct decode_cache *c = &ctxt->decode;
- switch (c->modrm_reg) {
- case 0: /* rol */
- emulate_2op_SrcB("rol", c->src, c->dst, ctxt->eflags);
- break;
- case 1: /* ror */
- emulate_2op_SrcB("ror", c->src, c->dst, ctxt->eflags);
- break;
- case 2: /* rcl */
- emulate_2op_SrcB("rcl", c->src, c->dst, ctxt->eflags);
- break;
- case 3: /* rcr */
- emulate_2op_SrcB("rcr", c->src, c->dst, ctxt->eflags);
- break;
- case 4: /* sal/shl */
- case 6: /* sal/shl */
- emulate_2op_SrcB("sal", c->src, c->dst, ctxt->eflags);
- break;
- case 5: /* shr */
- emulate_2op_SrcB("shr", c->src, c->dst, ctxt->eflags);
- break;
- case 7: /* sar */
- emulate_2op_SrcB("sar", c->src, c->dst, ctxt->eflags);
- break;
- }
-}
-
-static inline int emulate_grp3(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops)
-{
- struct decode_cache *c = &ctxt->decode;
- int rc = 0;
-
- switch (c->modrm_reg) {
- case 0 ... 1: /* test */
- /*
- * Special case in Grp3: test has an immediate
- * source operand.
- */
- c->src.type = OP_IMM;
- c->src.ptr = (unsigned long *)c->eip;
- c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
- if (c->src.bytes == 8)
- c->src.bytes = 4;
- switch (c->src.bytes) {
- case 1:
- c->src.val = insn_fetch(s8, 1, c->eip);
- break;
- case 2:
- c->src.val = insn_fetch(s16, 2, c->eip);
- break;
- case 4:
- c->src.val = insn_fetch(s32, 4, c->eip);
- break;
- }
- emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags);
- break;
- case 2: /* not */
- c->dst.val = ~c->dst.val;
- break;
- case 3: /* neg */
- emulate_1op("neg", c->dst, ctxt->eflags);
- break;
- default:
- DPRINTF("Cannot emulate %02x\n", c->b);
- rc = X86EMUL_UNHANDLEABLE;
- break;
- }
-done:
- return rc;
-}
-
-static inline int emulate_grp45(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops)
-{
- struct decode_cache *c = &ctxt->decode;
- int rc;
-
- switch (c->modrm_reg) {
- case 0: /* inc */
- emulate_1op("inc", c->dst, ctxt->eflags);
- break;
- case 1: /* dec */
- emulate_1op("dec", c->dst, ctxt->eflags);
- break;
- case 4: /* jmp abs */
- if (c->b == 0xff)
- c->eip = c->dst.val;
- else {
- DPRINTF("Cannot emulate %02x\n", c->b);
- return X86EMUL_UNHANDLEABLE;
- }
- break;
- case 6: /* push */
-
- /* 64-bit mode: PUSH always pushes a 64-bit operand. */
-
- if (ctxt->mode == X86EMUL_MODE_PROT64) {
- c->dst.bytes = 8;
- rc = ops->read_std((unsigned long)c->dst.ptr,
- &c->dst.val, 8, ctxt->vcpu);
- if (rc != 0)
- return rc;
- }
- register_address_increment(c->regs[VCPU_REGS_RSP],
- -c->dst.bytes);
- rc = ops->write_emulated(register_address(ctxt->ss_base,
- c->regs[VCPU_REGS_RSP]), &c->dst.val,
- c->dst.bytes, ctxt->vcpu);
- if (rc != 0)
- return rc;
- c->dst.type = OP_NONE;
- break;
- default:
- DPRINTF("Cannot emulate %02x\n", c->b);
- return X86EMUL_UNHANDLEABLE;
- }
- return 0;
-}
-
-static inline int emulate_grp9(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops,
- unsigned long memop)
-{
- struct decode_cache *c = &ctxt->decode;
- u64 old, new;
- int rc;
-
- rc = ops->read_emulated(memop, &old, 8, ctxt->vcpu);
- if (rc != 0)
- return rc;
-
- if (((u32) (old >> 0) != (u32) c->regs[VCPU_REGS_RAX]) ||
- ((u32) (old >> 32) != (u32) c->regs[VCPU_REGS_RDX])) {
-
- c->regs[VCPU_REGS_RAX] = (u32) (old >> 0);
- c->regs[VCPU_REGS_RDX] = (u32) (old >> 32);
- ctxt->eflags &= ~EFLG_ZF;
-
- } else {
- new = ((u64)c->regs[VCPU_REGS_RCX] << 32) |
- (u32) c->regs[VCPU_REGS_RBX];
-
- rc = ops->cmpxchg_emulated(memop, &old, &new, 8, ctxt->vcpu);
- if (rc != 0)
- return rc;
- ctxt->eflags |= EFLG_ZF;
- }
- return 0;
-}
-
-static inline int writeback(struct x86_emulate_ctxt *ctxt,
- struct x86_emulate_ops *ops)
-{
- int rc;
- struct decode_cache *c = &ctxt->decode;
-
- switch (c->dst.type) {
- case OP_REG:
- /* The 4-byte case *is* correct:
- * in 64-bit mode we zero-extend.
- */
- switch (c->dst.bytes) {
- case 1:
- *(u8 *)c->dst.ptr = (u8)c->dst.val;
- break;
- case 2:
- *(u16 *)c->dst.ptr = (u16)c->dst.val;
- break;
- case 4:
- *c->dst.ptr = (u32)c->dst.val;
- break; /* 64b: zero-ext */
- case 8:
- *c->dst.ptr = c->dst.val;
- break;
- }
- break;
- case OP_MEM:
- if (c->lock_prefix)
- rc = ops->cmpxchg_emulated(
- (unsigned long)c->dst.ptr,
- &c->dst.orig_val,
- &c->dst.val,
- c->dst.bytes,
- ctxt->vcpu);
- else
- rc = ops->write_emulated(
- (unsigned long)c->dst.ptr,
- &c->dst.val,
- c->dst.bytes,
- ctxt->vcpu);
- if (rc != 0)
- return rc;
- break;
- case OP_NONE:
- /* no writeback */
- break;
- default:
- break;
- }
- return 0;
-}
-
-int
-x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
-{
- unsigned long memop = 0;
- u64 msr_data;
- unsigned long saved_eip = 0;
- struct decode_cache *c = &ctxt->decode;
- int rc = 0;
-
- /* Shadow copy of register state. Committed on successful emulation.
- * NOTE: we can copy them from vcpu as x86_decode_insn() doesn't
- * modify them.
- */
-
- memcpy(c->regs, ctxt->vcpu->arch.regs, sizeof c->regs);
- saved_eip = c->eip;
-
- if (((c->d & ModRM) && (c->modrm_mod != 3)) || (c->d & MemAbs))
- memop = c->modrm_ea;
-
- if (c->rep_prefix && (c->d & String)) {
- /* All REP prefixes have the same first termination condition */
- if (c->regs[VCPU_REGS_RCX] == 0) {
- ctxt->vcpu->arch.rip = c->eip;
- goto done;
- }
- /* The second termination condition only applies for REPE
- * and REPNE. Test if the repeat string operation prefix is
- * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the
- * corresponding termination condition according to:
- * - if REPE/REPZ and ZF = 0 then done
- * - if REPNE/REPNZ and ZF = 1 then done
- */
- if ((c->b == 0xa6) || (c->b == 0xa7) ||
- (c->b == 0xae) || (c->b == 0xaf)) {
- if ((c->rep_prefix == REPE_PREFIX) &&
- ((ctxt->eflags & EFLG_ZF) == 0)) {
- ctxt->vcpu->arch.rip = c->eip;
- goto done;
- }
- if ((c->rep_prefix == REPNE_PREFIX) &&
- ((ctxt->eflags & EFLG_ZF) == EFLG_ZF)) {
- ctxt->vcpu->arch.rip = c->eip;
- goto done;
- }
- }
- c->regs[VCPU_REGS_RCX]--;
- c->eip = ctxt->vcpu->arch.rip;
- }
-
- if (c->src.type == OP_MEM) {
- c->src.ptr = (unsigned long *)memop;
- c->src.val = 0;
- rc = ops->read_emulated((unsigned long)c->src.ptr,
- &c->src.val,
- c->src.bytes,
- ctxt->vcpu);
- if (rc != 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 *)memop;
- 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);
-
- c->dst.ptr = (void *)c->dst.ptr +
- (c->src.val & mask) / 8;
- }
- if (!(c->d & Mov) &&
- /* optimisation - avoid slow emulated read */
- ((rc = ops->read_emulated((unsigned long)c->dst.ptr,
- &c->dst.val,
- c->dst.bytes, ctxt->vcpu)) != 0))
- goto done;
- }
- c->dst.orig_val = c->dst.val;
-
-special_insn:
-
- if (c->twobyte)
- goto twobyte_insn;
-
- switch (c->b) {
- case 0x00 ... 0x05:
- add: /* add */
- emulate_2op_SrcV("add", c->src, c->dst, ctxt->eflags);
- break;
- case 0x08 ... 0x0d:
- or: /* or */
- emulate_2op_SrcV("or", c->src, c->dst, ctxt->eflags);
- break;
- case 0x10 ... 0x15:
- adc: /* adc */
- emulate_2op_SrcV("adc", c->src, c->dst, ctxt->eflags);
- break;
- case 0x18 ... 0x1d:
- sbb: /* sbb */
- emulate_2op_SrcV("sbb", c->src, c->dst, ctxt->eflags);
- break;
- case 0x20 ... 0x23:
- and: /* and */
- emulate_2op_SrcV("and", c->src, c->dst, ctxt->eflags);
- break;
- case 0x24: /* and al imm8 */
- c->dst.type = OP_REG;
- c->dst.ptr = &c->regs[VCPU_REGS_RAX];
- c->dst.val = *(u8 *)c->dst.ptr;
- c->dst.bytes = 1;
- c->dst.orig_val = c->dst.val;
- goto and;
- case 0x25: /* and ax imm16, or eax imm32 */
- c->dst.type = OP_REG;
- c->dst.bytes = c->op_bytes;
- c->dst.ptr = &c->regs[VCPU_REGS_RAX];
- if (c->op_bytes == 2)
- c->dst.val = *(u16 *)c->dst.ptr;
- else
- c->dst.val = *(u32 *)c->dst.ptr;
- c->dst.orig_val = c->dst.val;
- goto and;
- case 0x28 ... 0x2d:
- sub: /* sub */
- emulate_2op_SrcV("sub", c->src, c->dst, ctxt->eflags);
- break;
- case 0x30 ... 0x35:
- xor: /* xor */
- emulate_2op_SrcV("xor", c->src, c->dst, ctxt->eflags);
- break;
- case 0x38 ... 0x3d:
- cmp: /* cmp */
- emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags);
- break;
- case 0x40 ... 0x47: /* inc r16/r32 */
- emulate_1op("inc", c->dst, ctxt->eflags);
- break;
- case 0x48 ... 0x4f: /* dec r16/r32 */
- emulate_1op("dec", c->dst, ctxt->eflags);
- break;
- case 0x50 ... 0x57: /* push reg */
- c->dst.type = OP_MEM;
- c->dst.bytes = c->op_bytes;
- c->dst.val = c->src.val;
- register_address_increment(c->regs[VCPU_REGS_RSP],
- -c->op_bytes);
- c->dst.ptr = (void *) register_address(
- ctxt->ss_base, c->regs[VCPU_REGS_RSP]);
- break;
- case 0x58 ... 0x5f: /* pop reg */
- pop_instruction:
- if ((rc = ops->read_std(register_address(ctxt->ss_base,
- c->regs[VCPU_REGS_RSP]), c->dst.ptr,
- c->op_bytes, ctxt->vcpu)) != 0)
- goto done;
-
- register_address_increment(c->regs[VCPU_REGS_RSP],
- c->op_bytes);
- c->dst.type = OP_NONE; /* Disable writeback. */
- break;
- case 0x63: /* movsxd */
- if (ctxt->mode != X86EMUL_MODE_PROT64)
- goto cannot_emulate;
- c->dst.val = (s32) c->src.val;
- break;
- case 0x6a: /* push imm8 */
- c->src.val = 0L;
- c->src.val = insn_fetch(s8, 1, c->eip);
- emulate_push(ctxt);
- break;
- case 0x6c: /* insb */
- case 0x6d: /* insw/insd */
- if (kvm_emulate_pio_string(ctxt->vcpu, NULL,
- 1,
- (c->d & ByteOp) ? 1 : c->op_bytes,
- c->rep_prefix ?
- address_mask(c->regs[VCPU_REGS_RCX]) : 1,
- (ctxt->eflags & EFLG_DF),
- register_address(ctxt->es_base,
- c->regs[VCPU_REGS_RDI]),
- c->rep_prefix,
- c->regs[VCPU_REGS_RDX]) == 0) {
- c->eip = saved_eip;
- return -1;
- }
- return 0;
- case 0x6e: /* outsb */
- case 0x6f: /* outsw/outsd */
- if (kvm_emulate_pio_string(ctxt->vcpu, NULL,
- 0,
- (c->d & ByteOp) ? 1 : c->op_bytes,
- c->rep_prefix ?
- address_mask(c->regs[VCPU_REGS_RCX]) : 1,
- (ctxt->eflags & EFLG_DF),
- register_address(c->override_base ?
- *c->override_base :
- ctxt->ds_base,
- c->regs[VCPU_REGS_RSI]),
- c->rep_prefix,
- c->regs[VCPU_REGS_RDX]) == 0) {
- c->eip = saved_eip;
- return -1;
- }
- return 0;
- case 0x70 ... 0x7f: /* jcc (short) */ {
- int rel = insn_fetch(s8, 1, c->eip);
-
- if (test_cc(c->b, ctxt->eflags))
- JMP_REL(rel);
- break;
- }
- case 0x80 ... 0x83: /* Grp1 */
- switch (c->modrm_reg) {
- case 0:
- goto add;
- case 1:
- goto or;
- case 2:
- goto adc;
- case 3:
- goto sbb;
- case 4:
- goto and;
- case 5:
- goto sub;
- case 6:
- goto xor;
- case 7:
- goto cmp;
- }
- break;
- case 0x84 ... 0x85:
- emulate_2op_SrcV("test", c->src, c->dst, ctxt->eflags);
- break;
- case 0x86 ... 0x87: /* xchg */
- /* Write back the register source. */
- switch (c->dst.bytes) {
- case 1:
- *(u8 *) c->src.ptr = (u8) c->dst.val;
- break;
- case 2:
- *(u16 *) c->src.ptr = (u16) c->dst.val;
- break;
- case 4:
- *c->src.ptr = (u32) c->dst.val;
- break; /* 64b reg: zero-extend */
- case 8:
- *c->src.ptr = c->dst.val;
- break;
- }
- /*
- * Write back the memory destination with implicit LOCK
- * prefix.
- */
- c->dst.val = c->src.val;
- c->lock_prefix = 1;
- break;
- case 0x88 ... 0x8b: /* mov */
- goto mov;
- case 0x8d: /* lea r16/r32, m */
- c->dst.val = c->modrm_val;
- break;
- case 0x8f: /* pop (sole member of Grp1a) */
- rc = emulate_grp1a(ctxt, ops);
- if (rc != 0)
- goto done;
- break;
- case 0x9c: /* pushf */
- c->src.val = (unsigned long) ctxt->eflags;
- emulate_push(ctxt);
- break;
- case 0x9d: /* popf */
- c->dst.ptr = (unsigned long *) &ctxt->eflags;
- goto pop_instruction;
- case 0xa0 ... 0xa1: /* mov */
- c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX];
- c->dst.val = c->src.val;
- break;
- case 0xa2 ... 0xa3: /* mov */
- c->dst.val = (unsigned long)c->regs[VCPU_REGS_RAX];
- break;
- case 0xa4 ... 0xa5: /* movs */
- c->dst.type = OP_MEM;
- c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
- c->dst.ptr = (unsigned long *)register_address(
- ctxt->es_base,
- c->regs[VCPU_REGS_RDI]);
- if ((rc = ops->read_emulated(register_address(
- c->override_base ? *c->override_base :
- ctxt->ds_base,
- c->regs[VCPU_REGS_RSI]),
- &c->dst.val,
- c->dst.bytes, ctxt->vcpu)) != 0)
- goto done;
- register_address_increment(c->regs[VCPU_REGS_RSI],
- (ctxt->eflags & EFLG_DF) ? -c->dst.bytes
- : c->dst.bytes);
- register_address_increment(c->regs[VCPU_REGS_RDI],
- (ctxt->eflags & EFLG_DF) ? -c->dst.bytes
- : c->dst.bytes);
- break;
- case 0xa6 ... 0xa7: /* cmps */
- c->src.type = OP_NONE; /* Disable writeback. */
- c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
- c->src.ptr = (unsigned long *)register_address(
- c->override_base ? *c->override_base :
- ctxt->ds_base,
- c->regs[VCPU_REGS_RSI]);
- if ((rc = ops->read_emulated((unsigned long)c->src.ptr,
- &c->src.val,
- c->src.bytes,
- ctxt->vcpu)) != 0)
- goto done;
-
- c->dst.type = OP_NONE; /* Disable writeback. */
- c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
- c->dst.ptr = (unsigned long *)register_address(
- ctxt->es_base,
- c->regs[VCPU_REGS_RDI]);
- if ((rc = ops->read_emulated((unsigned long)c->dst.ptr,
- &c->dst.val,
- c->dst.bytes,
- ctxt->vcpu)) != 0)
- goto done;
-
- DPRINTF("cmps: mem1=0x%p mem2=0x%p\n", c->src.ptr, c->dst.ptr);
-
- emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags);
-
- register_address_increment(c->regs[VCPU_REGS_RSI],
- (ctxt->eflags & EFLG_DF) ? -c->src.bytes
- : c->src.bytes);
- register_address_increment(c->regs[VCPU_REGS_RDI],
- (ctxt->eflags & EFLG_DF) ? -c->dst.bytes
- : c->dst.bytes);
-
- break;
- case 0xaa ... 0xab: /* stos */
- c->dst.type = OP_MEM;
- c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
- c->dst.ptr = (unsigned long *)register_address(
- ctxt->es_base,
- c->regs[VCPU_REGS_RDI]);
- c->dst.val = c->regs[VCPU_REGS_RAX];
- register_address_increment(c->regs[VCPU_REGS_RDI],
- (ctxt->eflags & EFLG_DF) ? -c->dst.bytes
- : c->dst.bytes);
- break;
- case 0xac ... 0xad: /* lods */
- c->dst.type = OP_REG;
- c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes;
- c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX];
- if ((rc = ops->read_emulated(register_address(
- c->override_base ? *c->override_base :
- ctxt->ds_base,
- c->regs[VCPU_REGS_RSI]),
- &c->dst.val,
- c->dst.bytes,
- ctxt->vcpu)) != 0)
- goto done;
- register_address_increment(c->regs[VCPU_REGS_RSI],
- (ctxt->eflags & EFLG_DF) ? -c->dst.bytes
- : c->dst.bytes);
- break;
- case 0xae ... 0xaf: /* scas */
- DPRINTF("Urk! I don't handle SCAS.\n");
- goto cannot_emulate;
- case 0xc0 ... 0xc1:
- emulate_grp2(ctxt);
- break;
- case 0xc3: /* ret */
- c->dst.ptr = &c->eip;
- goto pop_instruction;
- case 0xc6 ... 0xc7: /* mov (sole member of Grp11) */
- mov:
- c->dst.val = c->src.val;
- break;
- case 0xd0 ... 0xd1: /* Grp2 */
- c->src.val = 1;
- emulate_grp2(ctxt);
- break;
- case 0xd2 ... 0xd3: /* Grp2 */
- c->src.val = c->regs[VCPU_REGS_RCX];
- emulate_grp2(ctxt);
- break;
- case 0xe8: /* call (near) */ {
- long int rel;
- switch (c->op_bytes) {
- case 2:
- rel = insn_fetch(s16, 2, c->eip);
- break;
- case 4:
- rel = insn_fetch(s32, 4, c->eip);
- break;
- default:
- DPRINTF("Call: Invalid op_bytes\n");
- goto cannot_emulate;
- }
- c->src.val = (unsigned long) c->eip;
- JMP_REL(rel);
- c->op_bytes = c->ad_bytes;
- emulate_push(ctxt);
- break;
- }
- case 0xe9: /* jmp rel */
- case 0xeb: /* jmp rel short */
- JMP_REL(c->src.val);
- c->dst.type = OP_NONE; /* Disable writeback. */
- break;
- case 0xf4: /* hlt */
- ctxt->vcpu->arch.halt_request = 1;
- goto done;
- case 0xf5: /* cmc */
- /* complement carry flag from eflags reg */
- ctxt->eflags ^= EFLG_CF;
- c->dst.type = OP_NONE; /* Disable writeback. */
- break;
- case 0xf6 ... 0xf7: /* Grp3 */
- rc = emulate_grp3(ctxt, ops);
- if (rc != 0)
- goto done;
- break;
- case 0xf8: /* clc */
- ctxt->eflags &= ~EFLG_CF;
- c->dst.type = OP_NONE; /* Disable writeback. */
- break;
- case 0xfa: /* cli */
- ctxt->eflags &= ~X86_EFLAGS_IF;
- c->dst.type = OP_NONE; /* Disable writeback. */
- break;
- case 0xfb: /* sti */
- ctxt->eflags |= X86_EFLAGS_IF;
- c->dst.type = OP_NONE; /* Disable writeback. */
- break;
- case 0xfe ... 0xff: /* Grp4/Grp5 */
- rc = emulate_grp45(ctxt, ops);
- if (rc != 0)
- goto done;
- break;
- }
-
-writeback:
- rc = writeback(ctxt, ops);
- if (rc != 0)
- goto done;
-
- /* Commit shadow register state. */
- memcpy(ctxt->vcpu->arch.regs, c->regs, sizeof c->regs);
- ctxt->vcpu->arch.rip = c->eip;
-
-done:
- if (rc == X86EMUL_UNHANDLEABLE) {
- c->eip = saved_eip;
- return -1;
- }
- return 0;
-
-twobyte_insn:
- switch (c->b) {
- case 0x01: /* lgdt, lidt, lmsw */
- switch (c->modrm_reg) {
- u16 size;
- unsigned long address;
-
- case 0: /* vmcall */
- if (c->modrm_mod != 3 || c->modrm_rm != 1)
- goto cannot_emulate;
-
- rc = kvm_fix_hypercall(ctxt->vcpu);
- if (rc)
- goto done;
-
- kvm_emulate_hypercall(ctxt->vcpu);
- break;
- case 2: /* lgdt */
- rc = read_descriptor(ctxt, ops, c->src.ptr,
- &size, &address, c->op_bytes);
- if (rc)
- goto done;
- realmode_lgdt(ctxt->vcpu, size, address);
- break;
- case 3: /* lidt/vmmcall */
- if (c->modrm_mod == 3 && c->modrm_rm == 1) {
- rc = kvm_fix_hypercall(ctxt->vcpu);
- if (rc)
- goto done;
- kvm_emulate_hypercall(ctxt->vcpu);
- } else {
- rc = read_descriptor(ctxt, ops, c->src.ptr,
- &size, &address,
- c->op_bytes);
- if (rc)
- goto done;
- realmode_lidt(ctxt->vcpu, size, address);
- }
- break;
- case 4: /* smsw */
- if (c->modrm_mod != 3)
- goto cannot_emulate;
- *(u16 *)&c->regs[c->modrm_rm]
- = realmode_get_cr(ctxt->vcpu, 0);
- break;
- case 6: /* lmsw */
- if (c->modrm_mod != 3)
- goto cannot_emulate;
- realmode_lmsw(ctxt->vcpu, (u16)c->modrm_val,
- &ctxt->eflags);
- break;
- case 7: /* invlpg*/
- emulate_invlpg(ctxt->vcpu, memop);
- break;
- default:
- goto cannot_emulate;
- }
- /* Disable writeback. */
- c->dst.type = OP_NONE;
- break;
- case 0x06:
- emulate_clts(ctxt->vcpu);
- c->dst.type = OP_NONE;
- break;
- case 0x08: /* invd */
- case 0x09: /* wbinvd */
- case 0x0d: /* GrpP (prefetch) */
- case 0x18: /* Grp16 (prefetch/nop) */
- c->dst.type = OP_NONE;
- break;
- case 0x20: /* mov cr, reg */
- if (c->modrm_mod != 3)
- goto cannot_emulate;
- c->regs[c->modrm_rm] =
- realmode_get_cr(ctxt->vcpu, c->modrm_reg);
- c->dst.type = OP_NONE; /* no writeback */
- break;
- case 0x21: /* mov from dr to reg */
- if (c->modrm_mod != 3)
- goto cannot_emulate;
- rc = emulator_get_dr(ctxt, c->modrm_reg, &c->regs[c->modrm_rm]);
- if (rc)
- goto cannot_emulate;
- c->dst.type = OP_NONE; /* no writeback */
- break;
- case 0x22: /* mov reg, cr */
- if (c->modrm_mod != 3)
- goto cannot_emulate;
- realmode_set_cr(ctxt->vcpu,
- c->modrm_reg, c->modrm_val, &ctxt->eflags);
- c->dst.type = OP_NONE;
- break;
- case 0x23: /* mov from reg to dr */
- if (c->modrm_mod != 3)
- goto cannot_emulate;
- rc = emulator_set_dr(ctxt, c->modrm_reg,
- c->regs[c->modrm_rm]);
- if (rc)
- goto cannot_emulate;
- c->dst.type = OP_NONE; /* no writeback */
- break;
- case 0x30:
- /* wrmsr */
- msr_data = (u32)c->regs[VCPU_REGS_RAX]
- | ((u64)c->regs[VCPU_REGS_RDX] << 32);
- rc = kvm_set_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], msr_data);
- if (rc) {
- kvm_inject_gp(ctxt->vcpu, 0);
- c->eip = ctxt->vcpu->arch.rip;
- }
- rc = X86EMUL_CONTINUE;
- c->dst.type = OP_NONE;
- break;
- case 0x32:
- /* rdmsr */
- rc = kvm_get_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], &msr_data);
- if (rc) {
- kvm_inject_gp(ctxt->vcpu, 0);
- c->eip = ctxt->vcpu->arch.rip;
- } else {
- c->regs[VCPU_REGS_RAX] = (u32)msr_data;
- c->regs[VCPU_REGS_RDX] = msr_data >> 32;
- }
- rc = X86EMUL_CONTINUE;
- c->dst.type = OP_NONE;
- break;
- case 0x40 ... 0x4f: /* cmov */
- c->dst.val = c->dst.orig_val = c->src.val;
- if (!test_cc(c->b, ctxt->eflags))
- c->dst.type = OP_NONE; /* no writeback */
- break;
- case 0x80 ... 0x8f: /* jnz rel, etc*/ {
- long int rel;
-
- switch (c->op_bytes) {
- case 2:
- rel = insn_fetch(s16, 2, c->eip);
- break;
- case 4:
- rel = insn_fetch(s32, 4, c->eip);
- break;
- case 8:
- rel = insn_fetch(s64, 8, c->eip);
- break;
- default:
- DPRINTF("jnz: Invalid op_bytes\n");
- goto cannot_emulate;
- }
- if (test_cc(c->b, ctxt->eflags))
- JMP_REL(rel);
- c->dst.type = OP_NONE;
- break;
- }
- case 0xa3:
- bt: /* bt */
- c->dst.type = OP_NONE;
- /* only subword offset */
- c->src.val &= (c->dst.bytes << 3) - 1;
- emulate_2op_SrcV_nobyte("bt", c->src, c->dst, ctxt->eflags);
- break;
- case 0xab:
- bts: /* bts */
- /* only subword offset */
- c->src.val &= (c->dst.bytes << 3) - 1;
- emulate_2op_SrcV_nobyte("bts", c->src, c->dst, ctxt->eflags);
- break;
- case 0xb0 ... 0xb1: /* cmpxchg */
- /*
- * Save real source value, then compare EAX against
- * destination.
- */
- c->src.orig_val = c->src.val;
- c->src.val = c->regs[VCPU_REGS_RAX];
- emulate_2op_SrcV("cmp", c->src, c->dst, ctxt->eflags);
- if (ctxt->eflags & EFLG_ZF) {
- /* Success: write back to memory. */
- c->dst.val = c->src.orig_val;
- } else {
- /* Failure: write the value we saw to EAX. */
- c->dst.type = OP_REG;
- c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX];
- }
- break;
- case 0xb3:
- btr: /* btr */
- /* only subword offset */
- c->src.val &= (c->dst.bytes << 3) - 1;
- emulate_2op_SrcV_nobyte("btr", c->src, c->dst, ctxt->eflags);
- break;
- case 0xb6 ... 0xb7: /* movzx */
- c->dst.bytes = c->op_bytes;
- c->dst.val = (c->d & ByteOp) ? (u8) c->src.val
- : (u16) c->src.val;
- break;
- case 0xba: /* Grp8 */
- switch (c->modrm_reg & 3) {
- case 0:
- goto bt;
- case 1:
- goto bts;
- case 2:
- goto btr;
- case 3:
- goto btc;
- }
- break;
- case 0xbb:
- btc: /* btc */
- /* only subword offset */
- c->src.val &= (c->dst.bytes << 3) - 1;
- emulate_2op_SrcV_nobyte("btc", c->src, c->dst, ctxt->eflags);
- break;
- case 0xbe ... 0xbf: /* movsx */
- c->dst.bytes = c->op_bytes;
- c->dst.val = (c->d & ByteOp) ? (s8) c->src.val :
- (s16) c->src.val;
- break;
- case 0xc3: /* movnti */
- c->dst.bytes = c->op_bytes;
- c->dst.val = (c->op_bytes == 4) ? (u32) c->src.val :
- (u64) c->src.val;
- break;
- case 0xc7: /* Grp9 (cmpxchg8b) */
- rc = emulate_grp9(ctxt, ops, memop);
- if (rc != 0)
- goto done;
- c->dst.type = OP_NONE;
- break;
- }
- goto writeback;
-
-cannot_emulate:
- DPRINTF("Cannot emulate %02x\n", c->b);
- c->eip = saved_eip;
- return -1;
-}
git.openpandora.org / pandora-kernel.git / blobdiff