From: Avi Kivity <[email protected]> No code changes.
Signed-off-by: Avi Kivity <[email protected]> Signed-off-by: Marcelo Tosatti <[email protected]> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 1d905cb..fbd265c 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -945,378 +945,6 @@ done: return rc; } -int -x86_decode_insn(struct x86_emulate_ctxt *ctxt) -{ - struct x86_emulate_ops *ops = ctxt->ops; - struct decode_cache *c = &ctxt->decode; - int rc = X86EMUL_CONTINUE; - int mode = ctxt->mode; - int def_op_bytes, def_ad_bytes, dual, goffset; - struct opcode opcode, *g_mod012, *g_mod3; - - /* we cannot decode insn before we complete previous rep insn */ - WARN_ON(ctxt->restart); - - c->eip = ctxt->eip; - c->fetch.start = c->fetch.end = c->eip; - ctxt->cs_base = seg_base(ctxt, ops, VCPU_SREG_CS); - - switch (mode) { - case X86EMUL_MODE_REAL: - case X86EMUL_MODE_VM86: - 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 0x26: /* ES override */ - case 0x2e: /* CS override */ - case 0x36: /* SS override */ - case 0x3e: /* DS override */ - set_seg_override(c, (c->b >> 3) & 3); - break; - case 0x64: /* FS override */ - case 0x65: /* GS override */ - set_seg_override(c, c->b & 7); - 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). */ - opcode = opcode_table[c->b]; - if (opcode.flags == 0) { - /* Two-byte opcode? */ - if (c->b == 0x0f) { - c->twobyte = 1; - c->b = insn_fetch(u8, 1, c->eip); - opcode = twobyte_table[c->b]; - } - } - c->d = opcode.flags; - - if (c->d & Group) { - dual = c->d & GroupDual; - c->modrm = insn_fetch(u8, 1, c->eip); - --c->eip; - - if (c->d & GroupDual) { - g_mod012 = opcode.u.gdual->mod012; - g_mod3 = opcode.u.gdual->mod3; - } else - g_mod012 = g_mod3 = opcode.u.group; - - c->d &= ~(Group | GroupDual); - - goffset = (c->modrm >> 3) & 7; - - if ((c->modrm >> 6) == 3) - opcode = g_mod3[goffset]; - else - opcode = g_mod012[goffset]; - c->d |= opcode.flags; - } - - c->execute = opcode.u.execute; - - /* Unrecognised? */ - if (c->d == 0 || (c->d & Undefined)) { - 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 != X86EMUL_CONTINUE) - goto done; - - if (!c->has_seg_override) - set_seg_override(c, VCPU_SREG_DS); - - if (!(!c->twobyte && c->b == 0x8d)) - c->modrm_ea += seg_override_base(ctxt, ops, c); - - if (c->ad_bytes != 8) - c->modrm_ea = (u32)c->modrm_ea; - - if (c->rip_relative) - c->modrm_ea += c->eip; - - /* - * 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; - c->src.val = c->modrm_val; - c->src.ptr = c->modrm_ptr; - break; - } - c->src.type = OP_MEM; - c->src.ptr = (unsigned long *)c->modrm_ea; - c->src.val = 0; - break; - case SrcImm: - case SrcImmU: - 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; - } - if ((c->d & SrcMask) == SrcImmU) { - switch (c->src.bytes) { - case 1: - c->src.val &= 0xff; - break; - case 2: - c->src.val &= 0xffff; - break; - case 4: - c->src.val &= 0xffffffff; - break; - } - } - break; - case SrcImmByte: - case SrcImmUByte: - c->src.type = OP_IMM; - c->src.ptr = (unsigned long *)c->eip; - c->src.bytes = 1; - if ((c->d & SrcMask) == SrcImmByte) - c->src.val = insn_fetch(s8, 1, c->eip); - else - c->src.val = insn_fetch(u8, 1, c->eip); - break; - case SrcAcc: - c->src.type = OP_REG; - c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; - c->src.ptr = &c->regs[VCPU_REGS_RAX]; - switch (c->src.bytes) { - case 1: - c->src.val = *(u8 *)c->src.ptr; - break; - case 2: - c->src.val = *(u16 *)c->src.ptr; - break; - case 4: - c->src.val = *(u32 *)c->src.ptr; - break; - case 8: - c->src.val = *(u64 *)c->src.ptr; - break; - } - break; - case SrcOne: - c->src.bytes = 1; - c->src.val = 1; - break; - case SrcSI: - c->src.type = OP_MEM; - c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; - c->src.ptr = (unsigned long *) - register_address(c, seg_override_base(ctxt, ops, c), - c->regs[VCPU_REGS_RSI]); - c->src.val = 0; - break; - case SrcImmFAddr: - c->src.type = OP_IMM; - c->src.ptr = (unsigned long *)c->eip; - c->src.bytes = c->op_bytes + 2; - insn_fetch_arr(c->src.valptr, c->src.bytes, c->eip); - break; - case SrcMemFAddr: - c->src.type = OP_MEM; - c->src.ptr = (unsigned long *)c->modrm_ea; - c->src.bytes = c->op_bytes + 2; - break; - } - - /* - * Decode and fetch the second source operand: register, memory - * or immediate. - */ - switch (c->d & Src2Mask) { - case Src2None: - break; - case Src2CL: - c->src2.bytes = 1; - c->src2.val = c->regs[VCPU_REGS_RCX] & 0x8; - break; - case Src2ImmByte: - c->src2.type = OP_IMM; - c->src2.ptr = (unsigned long *)c->eip; - c->src2.bytes = 1; - c->src2.val = insn_fetch(u8, 1, c->eip); - break; - case Src2One: - c->src2.bytes = 1; - c->src2.val = 1; - 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: - case DstMem64: - if ((c->d & ModRM) && c->modrm_mod == 3) { - c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; - c->dst.type = OP_REG; - c->dst.val = c->dst.orig_val = c->modrm_val; - c->dst.ptr = c->modrm_ptr; - break; - } - c->dst.type = OP_MEM; - c->dst.ptr = (unsigned long *)c->modrm_ea; - if ((c->d & DstMask) == DstMem64) - c->dst.bytes = 8; - else - 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; - } - break; - case DstAcc: - c->dst.type = OP_REG; - c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; - c->dst.ptr = &c->regs[VCPU_REGS_RAX]; - switch (c->dst.bytes) { - case 1: - c->dst.val = *(u8 *)c->dst.ptr; - break; - case 2: - c->dst.val = *(u16 *)c->dst.ptr; - break; - case 4: - c->dst.val = *(u32 *)c->dst.ptr; - break; - case 8: - c->dst.val = *(u64 *)c->dst.ptr; - break; - } - c->dst.orig_val = c->dst.val; - break; - case DstDI: - c->dst.type = OP_MEM; - c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; - c->dst.ptr = (unsigned long *) - register_address(c, es_base(ctxt, ops), - c->regs[VCPU_REGS_RDI]); - c->dst.val = 0; - break; - } - -done: - return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0; -} - static int read_emulated(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops, unsigned long addr, void *dest, unsigned size) @@ -2626,6 +2254,378 @@ static void string_addr_inc(struct x86_emulate_ctxt *ctxt, unsigned long base, } int +x86_decode_insn(struct x86_emulate_ctxt *ctxt) +{ + struct x86_emulate_ops *ops = ctxt->ops; + struct decode_cache *c = &ctxt->decode; + int rc = X86EMUL_CONTINUE; + int mode = ctxt->mode; + int def_op_bytes, def_ad_bytes, dual, goffset; + struct opcode opcode, *g_mod012, *g_mod3; + + /* we cannot decode insn before we complete previous rep insn */ + WARN_ON(ctxt->restart); + + c->eip = ctxt->eip; + c->fetch.start = c->fetch.end = c->eip; + ctxt->cs_base = seg_base(ctxt, ops, VCPU_SREG_CS); + + switch (mode) { + case X86EMUL_MODE_REAL: + case X86EMUL_MODE_VM86: + 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 0x26: /* ES override */ + case 0x2e: /* CS override */ + case 0x36: /* SS override */ + case 0x3e: /* DS override */ + set_seg_override(c, (c->b >> 3) & 3); + break; + case 0x64: /* FS override */ + case 0x65: /* GS override */ + set_seg_override(c, c->b & 7); + 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). */ + opcode = opcode_table[c->b]; + if (opcode.flags == 0) { + /* Two-byte opcode? */ + if (c->b == 0x0f) { + c->twobyte = 1; + c->b = insn_fetch(u8, 1, c->eip); + opcode = twobyte_table[c->b]; + } + } + c->d = opcode.flags; + + if (c->d & Group) { + dual = c->d & GroupDual; + c->modrm = insn_fetch(u8, 1, c->eip); + --c->eip; + + if (c->d & GroupDual) { + g_mod012 = opcode.u.gdual->mod012; + g_mod3 = opcode.u.gdual->mod3; + } else + g_mod012 = g_mod3 = opcode.u.group; + + c->d &= ~(Group | GroupDual); + + goffset = (c->modrm >> 3) & 7; + + if ((c->modrm >> 6) == 3) + opcode = g_mod3[goffset]; + else + opcode = g_mod012[goffset]; + c->d |= opcode.flags; + } + + c->execute = opcode.u.execute; + + /* Unrecognised? */ + if (c->d == 0 || (c->d & Undefined)) { + 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 != X86EMUL_CONTINUE) + goto done; + + if (!c->has_seg_override) + set_seg_override(c, VCPU_SREG_DS); + + if (!(!c->twobyte && c->b == 0x8d)) + c->modrm_ea += seg_override_base(ctxt, ops, c); + + if (c->ad_bytes != 8) + c->modrm_ea = (u32)c->modrm_ea; + + if (c->rip_relative) + c->modrm_ea += c->eip; + + /* + * 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; + c->src.val = c->modrm_val; + c->src.ptr = c->modrm_ptr; + break; + } + c->src.type = OP_MEM; + c->src.ptr = (unsigned long *)c->modrm_ea; + c->src.val = 0; + break; + case SrcImm: + case SrcImmU: + 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; + } + if ((c->d & SrcMask) == SrcImmU) { + switch (c->src.bytes) { + case 1: + c->src.val &= 0xff; + break; + case 2: + c->src.val &= 0xffff; + break; + case 4: + c->src.val &= 0xffffffff; + break; + } + } + break; + case SrcImmByte: + case SrcImmUByte: + c->src.type = OP_IMM; + c->src.ptr = (unsigned long *)c->eip; + c->src.bytes = 1; + if ((c->d & SrcMask) == SrcImmByte) + c->src.val = insn_fetch(s8, 1, c->eip); + else + c->src.val = insn_fetch(u8, 1, c->eip); + break; + case SrcAcc: + c->src.type = OP_REG; + c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; + c->src.ptr = &c->regs[VCPU_REGS_RAX]; + switch (c->src.bytes) { + case 1: + c->src.val = *(u8 *)c->src.ptr; + break; + case 2: + c->src.val = *(u16 *)c->src.ptr; + break; + case 4: + c->src.val = *(u32 *)c->src.ptr; + break; + case 8: + c->src.val = *(u64 *)c->src.ptr; + break; + } + break; + case SrcOne: + c->src.bytes = 1; + c->src.val = 1; + break; + case SrcSI: + c->src.type = OP_MEM; + c->src.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; + c->src.ptr = (unsigned long *) + register_address(c, seg_override_base(ctxt, ops, c), + c->regs[VCPU_REGS_RSI]); + c->src.val = 0; + break; + case SrcImmFAddr: + c->src.type = OP_IMM; + c->src.ptr = (unsigned long *)c->eip; + c->src.bytes = c->op_bytes + 2; + insn_fetch_arr(c->src.valptr, c->src.bytes, c->eip); + break; + case SrcMemFAddr: + c->src.type = OP_MEM; + c->src.ptr = (unsigned long *)c->modrm_ea; + c->src.bytes = c->op_bytes + 2; + break; + } + + /* + * Decode and fetch the second source operand: register, memory + * or immediate. + */ + switch (c->d & Src2Mask) { + case Src2None: + break; + case Src2CL: + c->src2.bytes = 1; + c->src2.val = c->regs[VCPU_REGS_RCX] & 0x8; + break; + case Src2ImmByte: + c->src2.type = OP_IMM; + c->src2.ptr = (unsigned long *)c->eip; + c->src2.bytes = 1; + c->src2.val = insn_fetch(u8, 1, c->eip); + break; + case Src2One: + c->src2.bytes = 1; + c->src2.val = 1; + 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: + case DstMem64: + if ((c->d & ModRM) && c->modrm_mod == 3) { + c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; + c->dst.type = OP_REG; + c->dst.val = c->dst.orig_val = c->modrm_val; + c->dst.ptr = c->modrm_ptr; + break; + } + c->dst.type = OP_MEM; + c->dst.ptr = (unsigned long *)c->modrm_ea; + if ((c->d & DstMask) == DstMem64) + c->dst.bytes = 8; + else + 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; + } + break; + case DstAcc: + c->dst.type = OP_REG; + c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; + c->dst.ptr = &c->regs[VCPU_REGS_RAX]; + switch (c->dst.bytes) { + case 1: + c->dst.val = *(u8 *)c->dst.ptr; + break; + case 2: + c->dst.val = *(u16 *)c->dst.ptr; + break; + case 4: + c->dst.val = *(u32 *)c->dst.ptr; + break; + case 8: + c->dst.val = *(u64 *)c->dst.ptr; + break; + } + c->dst.orig_val = c->dst.val; + break; + case DstDI: + c->dst.type = OP_MEM; + c->dst.bytes = (c->d & ByteOp) ? 1 : c->op_bytes; + c->dst.ptr = (unsigned long *) + register_address(c, es_base(ctxt, ops), + c->regs[VCPU_REGS_RDI]); + c->dst.val = 0; + break; + } + +done: + return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0; +} + +int x86_emulate_insn(struct x86_emulate_ctxt *ctxt) { struct x86_emulate_ops *ops = ctxt->ops; -- To unsubscribe from this list: send the line "unsubscribe kvm-commits" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
