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-rw-r--r--arch/x86/kvm/x86_emulate.c1912
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diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c
new file mode 100644
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+++ b/arch/x86/kvm/x86_emulate.c
@@ -0,0 +1,1912 @@
+/******************************************************************************
+ * 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 <linux/kvm_host.h>
+#define DPRINTF(x...) do {} while (0)
+#endif
+#include <linux/module.h>
+#include <asm/kvm_x86_emulate.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 = &regs[modrm_reg];
+ if (highbyte_regs && modrm_reg >= 4 && modrm_reg < 8)
+ p = (unsigned char *)&regs[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;
+}