kvm/include/x86/asm/kvm_x86_emulate.h

   1 #ifndef KVM_UNIFDEF_H
   2 #define KVM_UNIFDEF_H
   3
   4 #ifdef __i386__
   5 #ifndef CONFIG_X86_32
   6 #define CONFIG_X86_32 1
   7 #endif
   8 #endif
   9
  10 #ifdef __x86_64__
  11 #ifndef CONFIG_X86_64
  12 #define CONFIG_X86_64 1
  13 #endif
  14 #endif
  15
  16 #if defined(__i386__) || defined (__x86_64__)
  17 #ifndef CONFIG_X86
  18 #define CONFIG_X86 1
  19 #endif
  20 #endif
  21
  22 #ifdef __ia64__
  23 #ifndef CONFIG_IA64
  24 #define CONFIG_IA64 1
  25 #endif
  26 #endif
  27
  28 #ifdef __PPC__
  29 #ifndef CONFIG_PPC
  30 #define CONFIG_PPC 1
  31 #endif
  32 #endif
  33
  34 #ifdef __s390__
  35 #ifndef CONFIG_S390
  36 #define CONFIG_S390 1
  37 #endif
  38 #endif
  39
  40 #endif
  41 /******************************************************************************
  42  * x86_emulate.h
  43  *
  44  * Generic x86 (32-bit and 64-bit) instruction decoder and emulator.
  45  *
  46  * Copyright (c) 2005 Keir Fraser
  47  *
  48  * From: xen-unstable 10676:af9809f51f81a3c43f276f00c81a52ef558afda4
  49  */
  50
  51 #ifndef _ASM_X86_KVM_X86_EMULATE_H
  52 #define _ASM_X86_KVM_X86_EMULATE_H
  53
  54 struct x86_emulate_ctxt;
  55
  56 /*
  57  * x86_emulate_ops:
  58  *
  59  * These operations represent the instruction emulator's interface to memory.
  60  * There are two categories of operation: those that act on ordinary memory
  61  * regions (*_std), and those that act on memory regions known to require
  62  * special treatment or emulation (*_emulated).
  63  *
  64  * The emulator assumes that an instruction accesses only one 'emulated memory'
  65  * location, that this location is the given linear faulting address (cr2), and
  66  * that this is one of the instruction's data operands. Instruction fetches and
  67  * stack operations are assumed never to access emulated memory. The emulator
  68  * automatically deduces which operand of a string-move operation is accessing
  69  * emulated memory, and assumes that the other operand accesses normal memory.
  70  *
  71  * NOTES:
  72  *  1. The emulator isn't very smart about emulated vs. standard memory.
  73  *     'Emulated memory' access addresses should be checked for sanity.
  74  *     'Normal memory' accesses may fault, and the caller must arrange to
  75  *     detect and handle reentrancy into the emulator via recursive faults.
  76  *     Accesses may be unaligned and may cross page boundaries.
  77  *  2. If the access fails (cannot emulate, or a standard access faults) then
  78  *     it is up to the memop to propagate the fault to the guest VM via
  79  *     some out-of-band mechanism, unknown to the emulator. The memop signals
  80  *     failure by returning X86EMUL_PROPAGATE_FAULT to the emulator, which will
  81  *     then immediately bail.
  82  *  3. Valid access sizes are 1, 2, 4 and 8 bytes. On x86/32 systems only
  83  *     cmpxchg8b_emulated need support 8-byte accesses.
  84  *  4. The emulator cannot handle 64-bit mode emulation on an x86/32 system.
  85  */
  86 /* Access completed successfully: continue emulation as normal. */
  87 #define X86EMUL_CONTINUE        0
  88 /* Access is unhandleable: bail from emulation and return error to caller. */
  89 #define X86EMUL_UNHANDLEABLE    1
  90 /* Terminate emulation but return success to the caller. */
  91 #define X86EMUL_PROPAGATE_FAULT 2 /* propagate a generated fault to guest */
  92 #define X86EMUL_RETRY_INSTR     2 /* retry the instruction for some reason */
  93 #define X86EMUL_CMPXCHG_FAILED  2 /* cmpxchg did not see expected value */
  94 struct x86_emulate_ops {
  95         /*
  96          * read_std: Read bytes of standard (non-emulated/special) memory.
  97          *           Used for instruction fetch, stack operations, and others.
  98          *  @addr:  [IN ] Linear address from which to read.
  99          *  @val:   [OUT] Value read from memory, zero-extended to 'u_long'.
 100          *  @bytes: [IN ] Number of bytes to read from memory.
 101          */
 102         int (*read_std)(unsigned long addr, void *val,
 103                         unsigned int bytes, struct kvm_vcpu *vcpu);
 104
 105         /*
 106          * read_emulated: Read bytes from emulated/special memory area.
 107          *  @addr:  [IN ] Linear address from which to read.
 108          *  @val:   [OUT] Value read from memory, zero-extended to 'u_long'.
 109          *  @bytes: [IN ] Number of bytes to read from memory.
 110          */
 111         int (*read_emulated)(unsigned long addr,
 112                              void *val,
 113                              unsigned int bytes,
 114                              struct kvm_vcpu *vcpu);
 115
 116         /*
 117          * write_emulated: Read bytes from emulated/special memory area.
 118          *  @addr:  [IN ] Linear address to which to write.
 119          *  @val:   [IN ] Value to write to memory (low-order bytes used as
 120          *                required).
 121          *  @bytes: [IN ] Number of bytes to write to memory.
 122          */
 123         int (*write_emulated)(unsigned long addr,
 124                               const void *val,
 125                               unsigned int bytes,
 126                               struct kvm_vcpu *vcpu);
 127
 128         /*
 129          * cmpxchg_emulated: Emulate an atomic (LOCKed) CMPXCHG operation on an
 130          *                   emulated/special memory area.
 131          *  @addr:  [IN ] Linear address to access.
 132          *  @old:   [IN ] Value expected to be current at @addr.
 133          *  @new:   [IN ] Value to write to @addr.
 134          *  @bytes: [IN ] Number of bytes to access using CMPXCHG.
 135          */
 136         int (*cmpxchg_emulated)(unsigned long addr,
 137                                 const void *old,
 138                                 const void *new,
 139                                 unsigned int bytes,
 140                                 struct kvm_vcpu *vcpu);
 141
 142 };
 143
 144 /* Type, address-of, and value of an instruction's operand. */
 145 struct operand {
 146         enum { OP_REG, OP_MEM, OP_IMM, OP_NONE } type;
 147         unsigned int bytes;
 148         unsigned long val, orig_val, *ptr;
 149 };
 150
 151 struct fetch_cache {
 152         u8 data[15];
 153         unsigned long start;
 154         unsigned long end;
 155 };
 156
 157 struct decode_cache {
 158         u8 twobyte;
 159         u8 b;
 160         u8 lock_prefix;
 161         u8 rep_prefix;
 162         u8 op_bytes;
 163         u8 ad_bytes;
 164         u8 rex_prefix;
 165         struct operand src;
 166         struct operand src2;
 167         struct operand dst;
 168         bool has_seg_override;
 169         u8 seg_override;
 170         unsigned int d;
 171         unsigned long regs[NR_VCPU_REGS];
 172         unsigned long eip;
 173         /* modrm */
 174         u8 modrm;
 175         u8 modrm_mod;
 176         u8 modrm_reg;
 177         u8 modrm_rm;
 178         u8 use_modrm_ea;
 179         bool rip_relative;
 180         unsigned long modrm_ea;
 181         void *modrm_ptr;
 182         unsigned long modrm_val;
 183         struct fetch_cache fetch;
 184 };
 185
 186 struct x86_emulate_ctxt {
 187         /* Register state before/after emulation. */
 188         struct kvm_vcpu *vcpu;
 189
 190         unsigned long eflags;
 191         /* Emulated execution mode, represented by an X86EMUL_MODE value. */
 192         int mode;
 193         u32 cs_base;
 194
 195         /* decode cache */
 196         struct decode_cache decode;
 197 };
 198
 199 /* Repeat String Operation Prefix */
 200 #define REPE_PREFIX     1
 201 #define REPNE_PREFIX    2
 202
 203 /* Execution mode, passed to the emulator. */
 204 #define X86EMUL_MODE_REAL     0 /* Real mode.             */
 205 #define X86EMUL_MODE_PROT16   2 /* 16-bit protected mode. */
 206 #define X86EMUL_MODE_PROT32   4 /* 32-bit protected mode. */
 207 #define X86EMUL_MODE_PROT64   8 /* 64-bit (long) mode.    */
 208
 209 /* Host execution mode. */
 210 #if defined(CONFIG_X86_32)
 211 #define X86EMUL_MODE_HOST X86EMUL_MODE_PROT32
 212 #elif defined(CONFIG_X86_64)
 213 #define X86EMUL_MODE_HOST X86EMUL_MODE_PROT64
 214 #endif
 215
 216 int x86_decode_insn(struct x86_emulate_ctxt *ctxt,
 217                     struct x86_emulate_ops *ops);
 218 int x86_emulate_insn(struct x86_emulate_ctxt *ctxt,
 219                      struct x86_emulate_ops *ops);
 220
 221 #endif /* _ASM_X86_KVM_X86_EMULATE_H */