diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/kvm/x86_emulate.c | 98 |
1 files changed, 52 insertions, 46 deletions
diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c index be70795b482..7513cddb929 100644 --- a/drivers/kvm/x86_emulate.c +++ b/drivers/kvm/x86_emulate.c @@ -61,6 +61,7 @@ #define ModRM (1<<6) /* Destination is only written; never read. */ #define Mov (1<<7) +#define BitOp (1<<8) static u8 opcode_table[256] = { /* 0x00 - 0x07 */ @@ -148,7 +149,7 @@ static u8 opcode_table[256] = { 0, 0, ByteOp | DstMem | SrcNone | ModRM, DstMem | SrcNone | ModRM }; -static u8 twobyte_table[256] = { +static u16 twobyte_table[256] = { /* 0x00 - 0x0F */ 0, SrcMem | ModRM | DstReg, 0, 0, 0, 0, ImplicitOps, 0, 0, 0, 0, 0, 0, ImplicitOps | ModRM, 0, 0, @@ -180,16 +181,16 @@ static u8 twobyte_table[256] = { /* 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, 0, 0, 0, 0, + 0, 0, 0, DstMem | SrcReg | ModRM | BitOp, 0, 0, 0, 0, /* 0xA8 - 0xAF */ - 0, 0, 0, DstMem | SrcReg | ModRM, 0, 0, 0, 0, + 0, 0, 0, DstMem | SrcReg | ModRM | BitOp, 0, 0, 0, 0, /* 0xB0 - 0xB7 */ ByteOp | DstMem | SrcReg | ModRM, DstMem | SrcReg | ModRM, 0, - DstMem | SrcReg | ModRM, + 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, + 0, 0, DstMem | SrcImmByte | ModRM, DstMem | SrcReg | ModRM | BitOp, 0, 0, ByteOp | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem16 | ModRM | Mov, /* 0xC0 - 0xCF */ @@ -469,7 +470,8 @@ static int read_descriptor(struct x86_emulate_ctxt *ctxt, int x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { - u8 b, d, sib, twobyte = 0, rex_prefix = 0; + unsigned d; + u8 b, sib, twobyte = 0, rex_prefix = 0; u8 modrm, modrm_mod = 0, modrm_reg = 0, modrm_rm = 0; unsigned long *override_base = NULL; unsigned int op_bytes, ad_bytes, lock_prefix = 0, rep_prefix = 0, i; @@ -726,46 +728,6 @@ done_prefixes: ; } - /* Decode and fetch the destination operand: register or memory. */ - switch (d & DstMask) { - case ImplicitOps: - /* Special instructions do their own operand decoding. */ - goto special_insn; - case DstReg: - dst.type = OP_REG; - if ((d & ByteOp) - && !(twobyte_table && (b == 0xb6 || b == 0xb7))) { - dst.ptr = decode_register(modrm_reg, _regs, - (rex_prefix == 0)); - dst.val = *(u8 *) dst.ptr; - dst.bytes = 1; - } else { - dst.ptr = decode_register(modrm_reg, _regs, 0); - switch ((dst.bytes = op_bytes)) { - case 2: - dst.val = *(u16 *)dst.ptr; - break; - case 4: - dst.val = *(u32 *)dst.ptr; - break; - case 8: - dst.val = *(u64 *)dst.ptr; - break; - } - } - break; - case DstMem: - dst.type = OP_MEM; - dst.ptr = (unsigned long *)cr2; - dst.bytes = (d & ByteOp) ? 1 : op_bytes; - if (!(d & Mov) && /* optimisation - avoid slow emulated read */ - ((rc = ops->read_emulated((unsigned long)dst.ptr, - &dst.val, dst.bytes, ctxt)) != 0)) - goto done; - break; - } - dst.orig_val = dst.val; - /* * Decode and fetch the source operand: register, memory * or immediate. @@ -838,6 +800,50 @@ done_prefixes: break; } + /* Decode and fetch the destination operand: register or memory. */ + switch (d & DstMask) { + case ImplicitOps: + /* Special instructions do their own operand decoding. */ + goto special_insn; + case DstReg: + dst.type = OP_REG; + if ((d & ByteOp) + && !(twobyte_table && (b == 0xb6 || b == 0xb7))) { + dst.ptr = decode_register(modrm_reg, _regs, + (rex_prefix == 0)); + dst.val = *(u8 *) dst.ptr; + dst.bytes = 1; + } else { + dst.ptr = decode_register(modrm_reg, _regs, 0); + switch ((dst.bytes = op_bytes)) { + case 2: + dst.val = *(u16 *)dst.ptr; + break; + case 4: + dst.val = *(u32 *)dst.ptr; + break; + case 8: + dst.val = *(u64 *)dst.ptr; + break; + } + } + break; + case DstMem: + dst.type = OP_MEM; + dst.ptr = (unsigned long *)cr2; + dst.bytes = (d & ByteOp) ? 1 : op_bytes; + if (d & BitOp) { + dst.ptr += src.val / BITS_PER_LONG; + dst.bytes = sizeof(long); + } + if (!(d & Mov) && /* optimisation - avoid slow emulated read */ + ((rc = ops->read_emulated((unsigned long)dst.ptr, + &dst.val, dst.bytes, ctxt)) != 0)) + goto done; + break; + } + dst.orig_val = dst.val; + if (twobyte) goto twobyte_insn; |