| /****************************************************************************** |
| * x86_emulate.h |
| * |
| * Generic x86 (32-bit and 64-bit) instruction decoder and emulator. |
| * |
| * Copyright (c) 2005 Keir Fraser |
| * |
| * From: xen-unstable 10676:af9809f51f81a3c43f276f00c81a52ef558afda4 |
| */ |
| |
| #ifndef _ASM_X86_KVM_X86_EMULATE_H |
| #define _ASM_X86_KVM_X86_EMULATE_H |
| |
| #include <asm/desc_defs.h> |
| |
| struct x86_emulate_ctxt; |
| enum x86_intercept; |
| enum x86_intercept_stage; |
| |
| struct x86_exception { |
| u8 vector; |
| bool error_code_valid; |
| u16 error_code; |
| bool nested_page_fault; |
| u64 address; /* cr2 or nested page fault gpa */ |
| }; |
| |
| /* |
| * This struct is used to carry enough information from the instruction |
| * decoder to main KVM so that a decision can be made whether the |
| * instruction needs to be intercepted or not. |
| */ |
| struct x86_instruction_info { |
| u8 intercept; /* which intercept */ |
| u8 rep_prefix; /* rep prefix? */ |
| u8 modrm_mod; /* mod part of modrm */ |
| u8 modrm_reg; /* index of register used */ |
| u8 modrm_rm; /* rm part of modrm */ |
| u64 src_val; /* value of source operand */ |
| u8 src_bytes; /* size of source operand */ |
| u8 dst_bytes; /* size of destination operand */ |
| u8 ad_bytes; /* size of src/dst address */ |
| u64 next_rip; /* rip following the instruction */ |
| }; |
| |
| /* |
| * x86_emulate_ops: |
| * |
| * These operations represent the instruction emulator's interface to memory. |
| * There are two categories of operation: those that act on ordinary memory |
| * regions (*_std), and those that act on memory regions known to require |
| * special treatment or emulation (*_emulated). |
| * |
| * The emulator assumes that an instruction accesses only one 'emulated memory' |
| * location, that this location is the given linear faulting address (cr2), and |
| * that this is one of the instruction's data operands. Instruction fetches and |
| * stack operations are assumed never to access emulated memory. The emulator |
| * automatically deduces which operand of a string-move operation is accessing |
| * emulated memory, and assumes that the other operand accesses normal memory. |
| * |
| * NOTES: |
| * 1. The emulator isn't very smart about emulated vs. standard memory. |
| * 'Emulated memory' access addresses should be checked for sanity. |
| * 'Normal memory' accesses may fault, and the caller must arrange to |
| * detect and handle reentrancy into the emulator via recursive faults. |
| * Accesses may be unaligned and may cross page boundaries. |
| * 2. If the access fails (cannot emulate, or a standard access faults) then |
| * it is up to the memop to propagate the fault to the guest VM via |
| * some out-of-band mechanism, unknown to the emulator. The memop signals |
| * failure by returning X86EMUL_PROPAGATE_FAULT to the emulator, which will |
| * then immediately bail. |
| * 3. Valid access sizes are 1, 2, 4 and 8 bytes. On x86/32 systems only |
| * cmpxchg8b_emulated need support 8-byte accesses. |
| * 4. The emulator cannot handle 64-bit mode emulation on an x86/32 system. |
| */ |
| /* Access completed successfully: continue emulation as normal. */ |
| #define X86EMUL_CONTINUE 0 |
| /* Access is unhandleable: bail from emulation and return error to caller. */ |
| #define X86EMUL_UNHANDLEABLE 1 |
| /* Terminate emulation but return success to the caller. */ |
| #define X86EMUL_PROPAGATE_FAULT 2 /* propagate a generated fault to guest */ |
| #define X86EMUL_RETRY_INSTR 3 /* retry the instruction for some reason */ |
| #define X86EMUL_CMPXCHG_FAILED 4 /* cmpxchg did not see expected value */ |
| #define X86EMUL_IO_NEEDED 5 /* IO is needed to complete emulation */ |
| #define X86EMUL_INTERCEPTED 6 /* Intercepted by nested VMCB/VMCS */ |
| |
| struct x86_emulate_ops { |
| /* |
| * read_gpr: read a general purpose register (rax - r15) |
| * |
| * @reg: gpr number. |
| */ |
| ulong (*read_gpr)(struct x86_emulate_ctxt *ctxt, unsigned reg); |
| /* |
| * write_gpr: write a general purpose register (rax - r15) |
| * |
| * @reg: gpr number. |
| * @val: value to write. |
| */ |
| void (*write_gpr)(struct x86_emulate_ctxt *ctxt, unsigned reg, ulong val); |
| /* |
| * read_std: Read bytes of standard (non-emulated/special) memory. |
| * Used for descriptor reading. |
| * @addr: [IN ] Linear address from which to read. |
| * @val: [OUT] Value read from memory, zero-extended to 'u_long'. |
| * @bytes: [IN ] Number of bytes to read from memory. |
| */ |
| int (*read_std)(struct x86_emulate_ctxt *ctxt, |
| unsigned long addr, void *val, |
| unsigned int bytes, |
| struct x86_exception *fault); |
| |
| /* |
| * write_std: Write bytes of standard (non-emulated/special) memory. |
| * Used for descriptor writing. |
| * @addr: [IN ] Linear address to which to write. |
| * @val: [OUT] Value write to memory, zero-extended to 'u_long'. |
| * @bytes: [IN ] Number of bytes to write to memory. |
| */ |
| int (*write_std)(struct x86_emulate_ctxt *ctxt, |
| unsigned long addr, void *val, unsigned int bytes, |
| struct x86_exception *fault); |
| /* |
| * fetch: Read bytes of standard (non-emulated/special) memory. |
| * Used for instruction fetch. |
| * @addr: [IN ] Linear address from which to read. |
| * @val: [OUT] Value read from memory, zero-extended to 'u_long'. |
| * @bytes: [IN ] Number of bytes to read from memory. |
| */ |
| int (*fetch)(struct x86_emulate_ctxt *ctxt, |
| unsigned long addr, void *val, unsigned int bytes, |
| struct x86_exception *fault); |
| |
| /* |
| * read_emulated: Read bytes from emulated/special memory area. |
| * @addr: [IN ] Linear address from which to read. |
| * @val: [OUT] Value read from memory, zero-extended to 'u_long'. |
| * @bytes: [IN ] Number of bytes to read from memory. |
| */ |
| int (*read_emulated)(struct x86_emulate_ctxt *ctxt, |
| unsigned long addr, void *val, unsigned int bytes, |
| struct x86_exception *fault); |
| |
| /* |
| * write_emulated: Write bytes to emulated/special memory area. |
| * @addr: [IN ] Linear address to which to write. |
| * @val: [IN ] Value to write to memory (low-order bytes used as |
| * required). |
| * @bytes: [IN ] Number of bytes to write to memory. |
| */ |
| int (*write_emulated)(struct x86_emulate_ctxt *ctxt, |
| unsigned long addr, const void *val, |
| unsigned int bytes, |
| struct x86_exception *fault); |
| |
| /* |
| * cmpxchg_emulated: Emulate an atomic (LOCKed) CMPXCHG operation on an |
| * emulated/special memory area. |
| * @addr: [IN ] Linear address to access. |
| * @old: [IN ] Value expected to be current at @addr. |
| * @new: [IN ] Value to write to @addr. |
| * @bytes: [IN ] Number of bytes to access using CMPXCHG. |
| */ |
| int (*cmpxchg_emulated)(struct x86_emulate_ctxt *ctxt, |
| unsigned long addr, |
| const void *old, |
| const void *new, |
| unsigned int bytes, |
| struct x86_exception *fault); |
| void (*invlpg)(struct x86_emulate_ctxt *ctxt, ulong addr); |
| |
| int (*pio_in_emulated)(struct x86_emulate_ctxt *ctxt, |
| int size, unsigned short port, void *val, |
| unsigned int count); |
| |
| int (*pio_out_emulated)(struct x86_emulate_ctxt *ctxt, |
| int size, unsigned short port, const void *val, |
| unsigned int count); |
| |
| bool (*get_segment)(struct x86_emulate_ctxt *ctxt, u16 *selector, |
| struct desc_struct *desc, u32 *base3, int seg); |
| void (*set_segment)(struct x86_emulate_ctxt *ctxt, u16 selector, |
| struct desc_struct *desc, u32 base3, int seg); |
| unsigned long (*get_cached_segment_base)(struct x86_emulate_ctxt *ctxt, |
| int seg); |
| void (*get_gdt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt); |
| void (*get_idt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt); |
| void (*set_gdt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt); |
| void (*set_idt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt); |
| ulong (*get_cr)(struct x86_emulate_ctxt *ctxt, int cr); |
| int (*set_cr)(struct x86_emulate_ctxt *ctxt, int cr, ulong val); |
| void (*set_rflags)(struct x86_emulate_ctxt *ctxt, ulong val); |
| int (*cpl)(struct x86_emulate_ctxt *ctxt); |
| int (*get_dr)(struct x86_emulate_ctxt *ctxt, int dr, ulong *dest); |
| int (*set_dr)(struct x86_emulate_ctxt *ctxt, int dr, ulong value); |
| int (*set_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 data); |
| int (*get_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata); |
| int (*read_pmc)(struct x86_emulate_ctxt *ctxt, u32 pmc, u64 *pdata); |
| void (*halt)(struct x86_emulate_ctxt *ctxt); |
| void (*wbinvd)(struct x86_emulate_ctxt *ctxt); |
| int (*fix_hypercall)(struct x86_emulate_ctxt *ctxt); |
| void (*get_fpu)(struct x86_emulate_ctxt *ctxt); /* disables preempt */ |
| void (*put_fpu)(struct x86_emulate_ctxt *ctxt); /* reenables preempt */ |
| int (*intercept)(struct x86_emulate_ctxt *ctxt, |
| struct x86_instruction_info *info, |
| enum x86_intercept_stage stage); |
| |
| void (*get_cpuid)(struct x86_emulate_ctxt *ctxt, |
| u32 *eax, u32 *ebx, u32 *ecx, u32 *edx); |
| }; |
| |
| typedef u32 __attribute__((vector_size(16))) sse128_t; |
| |
| /* Type, address-of, and value of an instruction's operand. */ |
| struct operand { |
| enum { OP_REG, OP_MEM, OP_MEM_STR, OP_IMM, OP_XMM, OP_MM, OP_NONE } type; |
| unsigned int bytes; |
| unsigned int count; |
| union { |
| unsigned long orig_val; |
| u64 orig_val64; |
| }; |
| union { |
| unsigned long *reg; |
| struct segmented_address { |
| ulong ea; |
| unsigned seg; |
| } mem; |
| unsigned xmm; |
| unsigned mm; |
| } addr; |
| union { |
| unsigned long val; |
| u64 val64; |
| char valptr[sizeof(unsigned long) + 2]; |
| sse128_t vec_val; |
| u64 mm_val; |
| void *data; |
| }; |
| }; |
| |
| struct fetch_cache { |
| u8 data[15]; |
| unsigned long start; |
| unsigned long end; |
| }; |
| |
| struct read_cache { |
| u8 data[1024]; |
| unsigned long pos; |
| unsigned long end; |
| }; |
| |
| /* Execution mode, passed to the emulator. */ |
| enum x86emul_mode { |
| X86EMUL_MODE_REAL, /* Real mode. */ |
| X86EMUL_MODE_VM86, /* Virtual 8086 mode. */ |
| X86EMUL_MODE_PROT16, /* 16-bit protected mode. */ |
| X86EMUL_MODE_PROT32, /* 32-bit protected mode. */ |
| X86EMUL_MODE_PROT64, /* 64-bit (long) mode. */ |
| }; |
| |
| struct x86_emulate_ctxt { |
| const struct x86_emulate_ops *ops; |
| |
| /* Register state before/after emulation. */ |
| unsigned long eflags; |
| unsigned long eip; /* eip before instruction emulation */ |
| /* Emulated execution mode, represented by an X86EMUL_MODE value. */ |
| enum x86emul_mode mode; |
| |
| /* interruptibility state, as a result of execution of STI or MOV SS */ |
| int interruptibility; |
| |
| bool guest_mode; /* guest running a nested guest */ |
| bool perm_ok; /* do not check permissions if true */ |
| bool only_vendor_specific_insn; |
| |
| bool have_exception; |
| struct x86_exception exception; |
| |
| /* decode cache */ |
| u8 twobyte; |
| u8 b; |
| u8 intercept; |
| u8 lock_prefix; |
| u8 rep_prefix; |
| u8 op_bytes; |
| u8 ad_bytes; |
| u8 rex_prefix; |
| struct operand src; |
| struct operand src2; |
| struct operand dst; |
| bool has_seg_override; |
| u8 seg_override; |
| u64 d; |
| int (*execute)(struct x86_emulate_ctxt *ctxt); |
| int (*check_perm)(struct x86_emulate_ctxt *ctxt); |
| /* modrm */ |
| u8 modrm; |
| u8 modrm_mod; |
| u8 modrm_reg; |
| u8 modrm_rm; |
| u8 modrm_seg; |
| bool rip_relative; |
| unsigned long _eip; |
| struct operand memop; |
| u32 regs_valid; /* bitmaps of registers in _regs[] that can be read */ |
| u32 regs_dirty; /* bitmaps of registers in _regs[] that have been written */ |
| /* Fields above regs are cleared together. */ |
| unsigned long _regs[NR_VCPU_REGS]; |
| struct operand *memopp; |
| struct fetch_cache fetch; |
| struct read_cache io_read; |
| struct read_cache mem_read; |
| }; |
| |
| /* Repeat String Operation Prefix */ |
| #define REPE_PREFIX 0xf3 |
| #define REPNE_PREFIX 0xf2 |
| |
| /* CPUID vendors */ |
| #define X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx 0x68747541 |
| #define X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx 0x444d4163 |
| #define X86EMUL_CPUID_VENDOR_AuthenticAMD_edx 0x69746e65 |
| |
| #define X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx 0x69444d41 |
| #define X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx 0x21726574 |
| #define X86EMUL_CPUID_VENDOR_AMDisbetterI_edx 0x74656273 |
| |
| #define X86EMUL_CPUID_VENDOR_GenuineIntel_ebx 0x756e6547 |
| #define X86EMUL_CPUID_VENDOR_GenuineIntel_ecx 0x6c65746e |
| #define X86EMUL_CPUID_VENDOR_GenuineIntel_edx 0x49656e69 |
| |
| enum x86_intercept_stage { |
| X86_ICTP_NONE = 0, /* Allow zero-init to not match anything */ |
| X86_ICPT_PRE_EXCEPT, |
| X86_ICPT_POST_EXCEPT, |
| X86_ICPT_POST_MEMACCESS, |
| }; |
| |
| enum x86_intercept { |
| x86_intercept_none, |
| x86_intercept_cr_read, |
| x86_intercept_cr_write, |
| x86_intercept_clts, |
| x86_intercept_lmsw, |
| x86_intercept_smsw, |
| x86_intercept_dr_read, |
| x86_intercept_dr_write, |
| x86_intercept_lidt, |
| x86_intercept_sidt, |
| x86_intercept_lgdt, |
| x86_intercept_sgdt, |
| x86_intercept_lldt, |
| x86_intercept_sldt, |
| x86_intercept_ltr, |
| x86_intercept_str, |
| x86_intercept_rdtsc, |
| x86_intercept_rdpmc, |
| x86_intercept_pushf, |
| x86_intercept_popf, |
| x86_intercept_cpuid, |
| x86_intercept_rsm, |
| x86_intercept_iret, |
| x86_intercept_intn, |
| x86_intercept_invd, |
| x86_intercept_pause, |
| x86_intercept_hlt, |
| x86_intercept_invlpg, |
| x86_intercept_invlpga, |
| x86_intercept_vmrun, |
| x86_intercept_vmload, |
| x86_intercept_vmsave, |
| x86_intercept_vmmcall, |
| x86_intercept_stgi, |
| x86_intercept_clgi, |
| x86_intercept_skinit, |
| x86_intercept_rdtscp, |
| x86_intercept_icebp, |
| x86_intercept_wbinvd, |
| x86_intercept_monitor, |
| x86_intercept_mwait, |
| x86_intercept_rdmsr, |
| x86_intercept_wrmsr, |
| x86_intercept_in, |
| x86_intercept_ins, |
| x86_intercept_out, |
| x86_intercept_outs, |
| |
| nr_x86_intercepts |
| }; |
| |
| /* Host execution mode. */ |
| #if defined(CONFIG_X86_32) |
| #define X86EMUL_MODE_HOST X86EMUL_MODE_PROT32 |
| #elif defined(CONFIG_X86_64) |
| #define X86EMUL_MODE_HOST X86EMUL_MODE_PROT64 |
| #endif |
| |
| int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len); |
| bool x86_page_table_writing_insn(struct x86_emulate_ctxt *ctxt); |
| #define EMULATION_FAILED -1 |
| #define EMULATION_OK 0 |
| #define EMULATION_RESTART 1 |
| #define EMULATION_INTERCEPTED 2 |
| int x86_emulate_insn(struct x86_emulate_ctxt *ctxt); |
| int emulator_task_switch(struct x86_emulate_ctxt *ctxt, |
| u16 tss_selector, int idt_index, int reason, |
| bool has_error_code, u32 error_code); |
| int emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq); |
| void emulator_invalidate_register_cache(struct x86_emulate_ctxt *ctxt); |
| void emulator_writeback_register_cache(struct x86_emulate_ctxt *ctxt); |
| |
| #endif /* _ASM_X86_KVM_X86_EMULATE_H */ |
