1 #ifndef __VMM_EMULATE_H
2 #define __VMM_EMULATE_H
3 #include <palacios/vm_guest.h>
4 #include <palacios/vmm.h>
7 * This is where we do the hideous X86 instruction parsing among other things
8 * We can parse out the instruction prefixes, as well as decode the operands
11 typedef enum {INVALID_OPERAND, REG_OPERAND, MEM_OPERAND} operand_type_t;
23 /* This parses an instruction
24 * All addresses in arguments are in the host address space
26 int v3_parse_instr(struct guest_info * info, // input
27 char * instr_ptr, // input
28 uint_t * instr_length, // output
29 struct x86_operand * src_operand, // output
30 struct x86_operand * dst_operand, // output
31 struct x86_operand * extra_operand); // output
36 * JRL: Some of this was taken from the Xen sources...
39 #define PACKED __attribute__((packed))
41 #define MODRM_MOD(x) ((x >> 6) & 0x3)
42 #define MODRM_REG(x) ((x >> 3) & 0x7)
43 #define MODRM_RM(x) (x & 0x7)
47 uint_t reg : 3 PACKED;
48 uint_t mod : 2 PACKED;
52 #define SIB_BASE(x) ((x >> 6) & 0x3)
53 #define SIB_INDEX(x) ((x >> 3) & 0x7)
54 #define SIB_SCALE(x) (x & 0x7)
57 uint_t base : 3 PACKED;
58 uint_t index : 3 PACKED;
59 uint_t scale : 2 PACKED;
64 #define MAKE_INSTR(nm, ...) static const uchar_t OPCODE_##nm[] = { __VA_ARGS__ }
67 * Here's how it works:
69 * Following bytes: Opcode bytes.
70 * Special case: Last byte, if zero, doesn't need to match.
72 MAKE_INSTR(INVD, 2, 0x0f, 0x08);
73 MAKE_INSTR(CPUID, 2, 0x0f, 0xa2);
74 MAKE_INSTR(RDMSR, 2, 0x0f, 0x32);
75 MAKE_INSTR(WRMSR, 2, 0x0f, 0x30);
76 MAKE_INSTR(RDTSC, 2, 0x0f, 0x31);
77 MAKE_INSTR(RDTSCP, 3, 0x0f, 0x01, 0xf9);
78 MAKE_INSTR(CLI, 1, 0xfa);
79 MAKE_INSTR(STI, 1, 0xfb);
80 MAKE_INSTR(RDPMC, 2, 0x0f, 0x33);
81 MAKE_INSTR(CLGI, 3, 0x0f, 0x01, 0xdd);
82 MAKE_INSTR(STGI, 3, 0x0f, 0x01, 0xdc);
83 MAKE_INSTR(VMRUN, 3, 0x0f, 0x01, 0xd8);
84 MAKE_INSTR(VMLOAD, 3, 0x0f, 0x01, 0xda);
85 MAKE_INSTR(VMSAVE, 3, 0x0f, 0x01, 0xdb);
86 MAKE_INSTR(VMCALL, 3, 0x0f, 0x01, 0xd9);
87 MAKE_INSTR(PAUSE, 2, 0xf3, 0x90);
88 MAKE_INSTR(SKINIT, 3, 0x0f, 0x01, 0xde);
89 MAKE_INSTR(MOV2CR, 3, 0x0f, 0x22, 0x00);
90 MAKE_INSTR(MOVCR2, 3, 0x0f, 0x20, 0x00);
91 MAKE_INSTR(MOV2DR, 3, 0x0f, 0x23, 0x00);
92 MAKE_INSTR(MOVDR2, 3, 0x0f, 0x21, 0x00);
93 MAKE_INSTR(PUSHF, 1, 0x9c);
94 MAKE_INSTR(POPF, 1, 0x9d);
95 MAKE_INSTR(RSM, 2, 0x0f, 0xaa);
96 MAKE_INSTR(INVLPG, 3, 0x0f, 0x01, 0x00);
97 MAKE_INSTR(INVLPGA,3, 0x0f, 0x01, 0xdf);
98 MAKE_INSTR(HLT, 1, 0xf4);
99 MAKE_INSTR(CLTS, 2, 0x0f, 0x06);
100 MAKE_INSTR(LMSW, 3, 0x0f, 0x01, 0x00);
101 MAKE_INSTR(SMSW, 3, 0x0f, 0x01, 0x00);
104 static const uchar_t PREFIX_LOCK = 0xF0;
105 static const uchar_t PREFIX_REPNE = 0xF2;
106 static const uchar_t PREFIX_REPNZ = 0xF2;
107 static const uchar_t PREFIX_REP = 0xF3;
108 static const uchar_t PREFIX_REPE = 0xF3;
109 static const uchar_t PREFIX_REPZ = 0xF3;
110 static const uchar_t PREFIX_CS_OVERRIDE = 0x2E;
111 static const uchar_t PREFIX_SS_OVERRIDE = 0x36;
112 static const uchar_t PREFIX_DS_OVERRIDE = 0x3E;
113 static const uchar_t PREFIX_ES_OVERRIDE = 0x26;
114 static const uchar_t PREFIX_FS_OVERRIDE = 0x64;
115 static const uchar_t PREFIX_GS_OVERRIDE = 0x65;
116 static const uchar_t PREFIX_BR_NOT_TAKEN = 0x2E;
117 static const uchar_t PREFIX_BR_TAKEN = 0x3E;
118 static const uchar_t PREFIX_OP_SIZE = 0x66;
119 static const uchar_t PREFIX_ADDR_SIZE = 0x67;
121 static inline int is_prefix_byte(char byte) {
124 case 0xF2: // REPNE/REPNZ
125 case 0xF3: // REP or REPE/REPZ
126 case 0x2E: // CS override or Branch hint not taken (with Jcc instrs)
127 case 0x36: // SS override
128 case 0x3E: // DS override or Branch hint taken (with Jcc instrs)
129 case 0x26: // ES override
130 case 0x64: // FS override
131 case 0x65: // GS override
132 //case 0x2E: // branch not taken hint
133 // case 0x3E: // branch taken hint
134 case 0x66: // operand size override
135 case 0x67: // address size override
145 static inline v3_reg_t get_gpr_mask(struct guest_info * info) {
146 switch (info->cpu_mode) {
160 static inline addr_t get_addr_linear(struct guest_info * info, addr_t addr, struct v3_segment * seg) {
161 switch (info->cpu_mode) {
163 return addr + (seg->selector << 4);
167 return addr + seg->base;
176 typedef enum {INVALID_ADDR_TYPE, REG, DISP0, DISP8, DISP16, DISP32} modrm_mode_t;
177 typedef enum {INVALID_REG_SIZE, REG64, REG32, REG16, REG8} reg_size_t;
186 static inline addr_t decode_register(struct v3_gprs * gprs, char reg_code, reg_size_t reg_size) {
191 reg_addr = (addr_t)&(gprs->rax);
194 reg_addr = (addr_t)&(gprs->rcx);
197 reg_addr = (addr_t)&(gprs->rdx);
200 reg_addr = (addr_t)&(gprs->rbx);
203 if (reg_size == REG8) {
204 reg_addr = (addr_t)&(gprs->rax) + 1;
206 reg_addr = (addr_t)&(gprs->rsp);
210 if (reg_size == REG8) {
211 reg_addr = (addr_t)&(gprs->rcx) + 1;
213 reg_addr = (addr_t)&(gprs->rbp);
217 if (reg_size == REG8) {
218 reg_addr = (addr_t)&(gprs->rdx) + 1;
220 reg_addr = (addr_t)&(gprs->rsi);
224 if (reg_size == REG8) {
225 reg_addr = (addr_t)&(gprs->rbx) + 1;
227 reg_addr = (addr_t)&(gprs->rdi);
240 static inline operand_type_t decode_operands16(struct v3_gprs * gprs, // input/output
241 char * modrm_instr, // input
242 int * offset, // output
243 addr_t * first_operand, // output
244 addr_t * second_operand, // output
245 reg_size_t reg_size) { // input
247 struct modrm_byte * modrm = (struct modrm_byte *)modrm_instr;
248 addr_t base_addr = 0;
249 modrm_mode_t mod_mode = 0;
250 operand_type_t addr_type = INVALID_OPERAND;
251 char * instr_cursor = modrm_instr;
253 PrintDebug("ModRM mod=%d\n", modrm->mod);
257 if (modrm->mod == 3) {
259 addr_type = REG_OPERAND;
260 PrintDebug("first operand = Register (RM=%d)\n",modrm->rm);
262 *first_operand = decode_register(gprs, modrm->rm, reg_size);
266 addr_type = MEM_OPERAND;
268 if (modrm->mod == 0) {
270 } else if (modrm->mod == 1) {
272 } else if (modrm->mod == 2) {
278 base_addr = gprs->rbx + gprs->rsi;
281 base_addr = gprs->rbx + gprs->rdi;
284 base_addr = gprs->rbp + gprs->rsi;
287 base_addr = gprs->rbp + gprs->rdi;
290 base_addr = gprs->rsi;
293 base_addr = gprs->rdi;
296 if (modrm->mod == 0) {
300 base_addr = gprs->rbp;
304 base_addr = gprs->rbx;
310 if (mod_mode == DISP8) {
311 base_addr += (uchar_t)*(instr_cursor);
313 } else if (mod_mode == DISP16) {
314 base_addr += (ushort_t)*(instr_cursor);
318 *first_operand = base_addr;
321 *offset += (instr_cursor - modrm_instr);
322 *second_operand = decode_register(gprs, modrm->reg, reg_size);
329 static inline operand_type_t decode_operands32(struct v3_gprs * gprs, // input/output
330 char * modrm_instr, // input
331 int * offset, // output
332 addr_t * first_operand, // output
333 addr_t * second_operand, // output
334 reg_size_t reg_size) { // input
336 char * instr_cursor = modrm_instr;
337 struct modrm_byte * modrm = (struct modrm_byte *)modrm_instr;
338 addr_t base_addr = 0;
339 modrm_mode_t mod_mode = 0;
340 uint_t has_sib_byte = 0;
341 operand_type_t addr_type = INVALID_OPERAND;
347 if (modrm->mod == 3) {
349 addr_type = REG_OPERAND;
351 PrintDebug("first operand = Register (RM=%d)\n",modrm->rm);
353 *first_operand = decode_register(gprs, modrm->rm, reg_size);
357 addr_type = MEM_OPERAND;
359 if (modrm->mod == 0) {
361 } else if (modrm->mod == 1) {
363 } else if (modrm->mod == 2) {
369 base_addr = gprs->rax;
372 base_addr = gprs->rcx;
375 base_addr = gprs->rdx;
378 base_addr = gprs->rbx;
384 if (modrm->mod == 0) {
388 base_addr = gprs->rbp;
392 base_addr = gprs->rsi;
395 base_addr = gprs->rdi;
401 struct sib_byte * sib = (struct sib_byte *)(instr_cursor);
407 if (sib->scale == 1) {
409 } else if (sib->scale == 2) {
411 } else if (sib->scale == 3) {
416 switch (sib->index) {
418 base_addr = gprs->rax;
421 base_addr = gprs->rcx;
424 base_addr = gprs->rdx;
427 base_addr = gprs->rbx;
433 base_addr = gprs->rbp;
436 base_addr = gprs->rsi;
439 base_addr = gprs->rdi;
448 base_addr += gprs->rax;
451 base_addr += gprs->rcx;
454 base_addr += gprs->rdx;
457 base_addr += gprs->rbx;
460 base_addr += gprs->rsp;
463 if (modrm->mod != 0) {
464 base_addr += gprs->rbp;
468 base_addr += gprs->rsi;
471 base_addr += gprs->rdi;
478 if (mod_mode == DISP8) {
479 base_addr += (uchar_t)*(instr_cursor);
481 } else if (mod_mode == DISP32) {
482 base_addr += (uint_t)*(instr_cursor);
487 *first_operand = base_addr;
490 *offset += (instr_cursor - modrm_instr);
492 *second_operand = decode_register(gprs, modrm->reg, reg_size);