diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c index dc9d2a870fbc0c6d1df3199e54e3d9bfd77b32fc..a156092792831394d955a71a2fed3a3106eedf89 100644 --- a/drivers/kvm/x86_emulate.c +++ b/drivers/kvm/x86_emulate.c @@ -907,6 +907,244 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) 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; + + /* 64-bit mode: POP always pops a 64-bit operand. */ + + if (ctxt->mode == X86EMUL_MODE_PROT64) + c->dst.bytes = 8; + + 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 decode_cache *c, unsigned long *_eflags) +{ + switch (c->modrm_reg) { + case 0: /* rol */ + emulate_2op_SrcB("rol", c->src, c->dst, *_eflags); + break; + case 1: /* ror */ + emulate_2op_SrcB("ror", c->src, c->dst, *_eflags); + break; + case 2: /* rcl */ + emulate_2op_SrcB("rcl", c->src, c->dst, *_eflags); + break; + case 3: /* rcr */ + emulate_2op_SrcB("rcr", c->src, c->dst, *_eflags); + break; + case 4: /* sal/shl */ + case 6: /* sal/shl */ + emulate_2op_SrcB("sal", c->src, c->dst, *_eflags); + break; + case 5: /* shr */ + emulate_2op_SrcB("shr", c->src, c->dst, *_eflags); + break; + case 7: /* sar */ + emulate_2op_SrcB("sar", c->src, c->dst, *_eflags); + break; + } +} + +static inline int emulate_grp3(struct x86_emulate_ctxt *ctxt, + struct x86_emulate_ops *ops, + unsigned long *_eflags) +{ + 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, *_eflags); + break; + case 2: /* not */ + c->dst.val = ~c->dst.val; + break; + case 3: /* neg */ + emulate_1op("neg", c->dst, *_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, + unsigned long *_eflags, + int *no_wb) +{ + struct decode_cache *c = &ctxt->decode; + int rc; + + switch (c->modrm_reg) { + case 0: /* inc */ + emulate_1op("inc", c->dst, *_eflags); + break; + case 1: /* dec */ + emulate_1op("dec", c->dst, *_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; + *no_wb = 1; + 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 *_eflags, + unsigned long cr2) +{ + struct decode_cache *c = &ctxt->decode; + u64 old, new; + int rc; + + rc = ops->read_emulated(cr2, &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); + *_eflags &= ~EFLG_ZF; + + } else { + new = ((u64)c->regs[VCPU_REGS_RCX] << 32) | + (u32) c->regs[VCPU_REGS_RBX]; + + rc = ops->cmpxchg_emulated(cr2, &old, &new, 8, ctxt->vcpu); + if (rc != 0) + return rc; + *_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; + default: + break; + } + return 0; +} + int x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { @@ -1042,7 +1280,6 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) } break; case 0x84 ... 0x85: - test: /* test */ emulate_2op_SrcV("test", c->src, c->dst, _eflags); break; case 0x86 ... 0x87: /* xchg */ @@ -1074,18 +1311,9 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) c->dst.val = c->modrm_val; break; case 0x8f: /* pop (sole member of Grp1a) */ - /* 64-bit mode: POP always pops a 64-bit operand. */ - if (ctxt->mode == X86EMUL_MODE_PROT64) - c->dst.bytes = 8; - if ((rc = ops->read_std(register_address( - ctxt->ss_base, - c->regs[VCPU_REGS_RSP]), - &c->dst.val, - c->dst.bytes, - ctxt->vcpu)) != 0) + rc = emulate_grp1a(ctxt, ops); + if (rc != 0) goto done; - register_address_increment(c->regs[VCPU_REGS_RSP], - c->dst.bytes); break; case 0xa0 ... 0xa1: /* mov */ c->dst.ptr = (unsigned long *)&c->regs[VCPU_REGS_RAX]; @@ -1099,31 +1327,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) c->eip += c->ad_bytes; break; case 0xc0 ... 0xc1: - grp2: /* Grp2 */ - switch (c->modrm_reg) { - case 0: /* rol */ - emulate_2op_SrcB("rol", c->src, c->dst, _eflags); - break; - case 1: /* ror */ - emulate_2op_SrcB("ror", c->src, c->dst, _eflags); - break; - case 2: /* rcl */ - emulate_2op_SrcB("rcl", c->src, c->dst, _eflags); - break; - case 3: /* rcr */ - emulate_2op_SrcB("rcr", c->src, c->dst, _eflags); - break; - case 4: /* sal/shl */ - case 6: /* sal/shl */ - emulate_2op_SrcB("sal", c->src, c->dst, _eflags); - break; - case 5: /* shr */ - emulate_2op_SrcB("shr", c->src, c->dst, _eflags); - break; - case 7: /* sar */ - emulate_2op_SrcB("sar", c->src, c->dst, _eflags); - break; - } + emulate_grp2(c, &_eflags); break; case 0xc6 ... 0xc7: /* mov (sole member of Grp11) */ mov: @@ -1131,126 +1335,29 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) break; case 0xd0 ... 0xd1: /* Grp2 */ c->src.val = 1; - goto grp2; + emulate_grp2(c, &_eflags); + break; case 0xd2 ... 0xd3: /* Grp2 */ c->src.val = c->regs[VCPU_REGS_RCX]; - goto grp2; + emulate_grp2(c, &_eflags); + break; case 0xf6 ... 0xf7: /* Grp3 */ - 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; - } - goto test; - case 2: /* not */ - c->dst.val = ~c->dst.val; - break; - case 3: /* neg */ - emulate_1op("neg", c->dst, _eflags); - break; - default: - goto cannot_emulate; - } + rc = emulate_grp3(ctxt, ops, &_eflags); + if (rc != 0) + goto done; break; case 0xfe ... 0xff: /* Grp4/Grp5 */ - switch (c->modrm_reg) { - case 0: /* inc */ - emulate_1op("inc", c->dst, _eflags); - break; - case 1: /* dec */ - emulate_1op("dec", c->dst, _eflags); - break; - case 4: /* jmp abs */ - if (c->b == 0xff) - c->eip = c->dst.val; - else - goto cannot_emulate; - break; - case 6: /* push */ - /* 64-bit mode: PUSH always pushes a 64-bit operand. */ - if (ctxt->mode == X86EMUL_MODE_PROT64) { - c->dst.bytes = 8; - if ((rc = ops->read_std( - (unsigned long)c->dst.ptr, - &c->dst.val, 8, - ctxt->vcpu)) != 0) - goto done; - } - register_address_increment(c->regs[VCPU_REGS_RSP], - -c->dst.bytes); - if ((rc = ops->write_emulated( - register_address(ctxt->ss_base, - c->regs[VCPU_REGS_RSP]), - &c->dst.val, - c->dst.bytes, ctxt->vcpu)) != 0) - goto done; - no_wb = 1; - break; - default: - goto cannot_emulate; - } + rc = emulate_grp45(ctxt, ops, &_eflags, &no_wb); + if (rc != 0) + goto done; break; } writeback: if (!no_wb) { - 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) - goto done; - default: - break; - } + rc = writeback(ctxt, ops); + if (rc != 0) + goto done; } /* Commit shadow register state. */ @@ -1283,8 +1390,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) ctxt->ss_base, c->regs[VCPU_REGS_RSP]); break; case 0x58 ... 0x5f: /* pop reg */ - c->dst.ptr = - (unsigned long *)&c->regs[c->b & 0x7]; + c->dst.ptr = (unsigned long *)&c->regs[c->b & 0x7]; pop_instruction: if ((rc = ops->read_std(register_address(ctxt->ss_base, c->regs[VCPU_REGS_RSP]), c->dst.ptr, @@ -1298,14 +1404,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) case 0x6a: /* push imm8 */ c->src.val = 0L; c->src.val = insn_fetch(s8, 1, c->eip); -push: - 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]); + emulate_push(ctxt); break; case 0x6c: /* insb */ case 0x6d: /* insw/insd */ @@ -1350,7 +1449,8 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) } case 0x9c: /* pushf */ c->src.val = (unsigned long) _eflags; - goto push; + emulate_push(ctxt); + break; case 0x9d: /* popf */ c->dst.ptr = (unsigned long *) &_eflags; goto pop_instruction; @@ -1436,7 +1536,8 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) c->src.val = (unsigned long) c->eip; JMP_REL(rel); c->op_bytes = c->ad_bytes; - goto push; + emulate_push(ctxt); + break; } case 0xe9: /* jmp rel */ case 0xeb: /* jmp rel short */ @@ -1511,8 +1612,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) no_wb = 1; if (c->modrm_mod != 3) goto cannot_emulate; - rc = emulator_get_dr(ctxt, c->modrm_reg, - &c->regs[c->modrm_rm]); + rc = emulator_get_dr(ctxt, c->modrm_reg, &c->regs[c->modrm_rm]); break; case 0x23: /* mov from reg to dr */ no_wb = 1; @@ -1668,8 +1768,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) break; case 0x32: /* rdmsr */ - rc = kvm_get_msr(ctxt->vcpu, - c->regs[VCPU_REGS_RCX], &msr_data); + rc = kvm_get_msr(ctxt->vcpu, c->regs[VCPU_REGS_RCX], &msr_data); if (rc) { kvm_x86_ops->inject_gp(ctxt->vcpu, 0); c->eip = ctxt->vcpu->rip; @@ -1701,28 +1800,10 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) break; } case 0xc7: /* Grp9 (cmpxchg8b) */ - { - u64 old, new; - if ((rc = ops->read_emulated(cr2, &old, 8, ctxt->vcpu)) - != 0) - goto done; - 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); - _eflags &= ~EFLG_ZF; - } else { - new = ((u64)c->regs[VCPU_REGS_RCX] << 32) - | (u32) c->regs[VCPU_REGS_RBX]; - if ((rc = ops->cmpxchg_emulated(cr2, &old, - &new, 8, ctxt->vcpu)) != 0) - goto done; - _eflags |= EFLG_ZF; - } - break; - } + rc = emulate_grp9(ctxt, ops, &_eflags, cr2); + if (rc != 0) + goto done; + break; } goto writeback;