1 #ifndef __VMM_EMULATE_H
2 #define __VMM_EMULATE_H
6 #include <palacios/vm_guest.h>
7 #include <palacios/vmm.h>
10 * This is where we do the hideous X86 instruction parsing among other things
11 * We can parse out the instruction prefixes, as well as decode the operands
18 typedef enum {INVALID_OPERAND, REG_OPERAND, MEM_OPERAND} operand_type_t;
26 struct x86_prefix_list {
27 uint_t lock : 1; // 0xF0
28 uint_t repne : 1; // 0xF2
29 uint_t repnz : 1; // 0xF2
30 uint_t rep : 1; // 0xF3
31 uint_t repe : 1; // 0xF3
32 uint_t repz : 1; // 0xF3
33 uint_t cs_override : 1; // 0x2E
34 uint_t ss_override : 1; // 0x36
35 uint_t ds_override : 1; // 0x3E
36 uint_t es_override : 1; // 0x26
37 uint_t fs_override : 1; // 0x64
38 uint_t gs_override : 1; // 0x65
39 uint_t br_not_taken : 1; // 0x2E
40 uint_t br_takend : 1; // 0x3E
41 uint_t op_size : 1; // 0x66
42 uint_t addr_size : 1; // 0x67
48 addr_t opcode; // a pointer to the V3_OPCODE_[*] arrays defined below
50 struct x86_prefix_list prefixes;
51 struct x86_operand first_operand;
52 struct x86_operand second_operand;
53 struct x86_operand third_operand;
58 /************************/
59 /* EXTERNAL DECODER API */
60 /************************/
62 This is an External API definition that must be implemented by a decoder
67 * Initializes a decoder
72 * Decodes an instruction
73 * All addresses in arguments are in the host address space
74 * instr_ptr is the host address of the instruction
75 * IMPORTANT: make sure the instr_ptr is in contiguous host memory
76 * ie. Copy it to a buffer before the call
78 int v3_decode(struct guest_info * info, addr_t instr_ptr, struct x86_instr * instr);
81 * Encodes an instruction
82 * All addresses in arguments are in the host address space
83 * The instruction is encoded from the struct, and copied into a 15 byte host buffer
84 * referenced by instr_buf
85 * any unused bytes at the end of instr_buf will be filled with nops
86 * IMPORTANT: instr_buf must be allocated and 15 bytes long
88 int v3_encode(struct guest_info * info, struct x86_instr * instr, char * instr_buf);
99 * JRL: Some of this was taken from the Xen sources...
102 #define PACKED __attribute__((packed))
104 #define MODRM_MOD(x) ((x >> 6) & 0x3)
105 #define MODRM_REG(x) ((x >> 3) & 0x7)
106 #define MODRM_RM(x) (x & 0x7)
109 uint_t rm : 3 PACKED;
110 uint_t reg : 3 PACKED;
111 uint_t mod : 2 PACKED;
115 #define SIB_BASE(x) ((x >> 6) & 0x3)
116 #define SIB_INDEX(x) ((x >> 3) & 0x7)
117 #define SIB_SCALE(x) (x & 0x7)
120 uint_t base : 3 PACKED;
121 uint_t index : 3 PACKED;
122 uint_t scale : 2 PACKED;
127 #define MAKE_INSTR(nm, ...) static const uchar_t V3_OPCODE_##nm[] = { __VA_ARGS__ }
130 * Here's how it works:
131 * First byte: Length.
132 * Following bytes: Opcode bytes.
133 * Special case: Last byte, if zero, doesn't need to match.
135 MAKE_INSTR(INVD, 2, 0x0f, 0x08);
136 MAKE_INSTR(CPUID, 2, 0x0f, 0xa2);
137 MAKE_INSTR(RDMSR, 2, 0x0f, 0x32);
138 MAKE_INSTR(WRMSR, 2, 0x0f, 0x30);
139 MAKE_INSTR(RDTSC, 2, 0x0f, 0x31);
140 MAKE_INSTR(RDTSCP, 3, 0x0f, 0x01, 0xf9);
141 MAKE_INSTR(CLI, 1, 0xfa);
142 MAKE_INSTR(STI, 1, 0xfb);
143 MAKE_INSTR(RDPMC, 2, 0x0f, 0x33);
144 MAKE_INSTR(CLGI, 3, 0x0f, 0x01, 0xdd);
145 MAKE_INSTR(STGI, 3, 0x0f, 0x01, 0xdc);
146 MAKE_INSTR(VMRUN, 3, 0x0f, 0x01, 0xd8);
147 MAKE_INSTR(VMLOAD, 3, 0x0f, 0x01, 0xda);
148 MAKE_INSTR(VMSAVE, 3, 0x0f, 0x01, 0xdb);
149 MAKE_INSTR(VMCALL, 3, 0x0f, 0x01, 0xd9);
150 MAKE_INSTR(PAUSE, 2, 0xf3, 0x90);
151 MAKE_INSTR(SKINIT, 3, 0x0f, 0x01, 0xde);
152 MAKE_INSTR(MOV2CR, 3, 0x0f, 0x22, 0x00);
153 MAKE_INSTR(MOVCR2, 3, 0x0f, 0x20, 0x00);
154 MAKE_INSTR(MOV2DR, 3, 0x0f, 0x23, 0x00);
155 MAKE_INSTR(MOVDR2, 3, 0x0f, 0x21, 0x00);
156 MAKE_INSTR(PUSHF, 1, 0x9c);
157 MAKE_INSTR(POPF, 1, 0x9d);
158 MAKE_INSTR(RSM, 2, 0x0f, 0xaa);
159 MAKE_INSTR(INVLPG, 3, 0x0f, 0x01, 0x00);
160 MAKE_INSTR(INVLPGA,3, 0x0f, 0x01, 0xdf);
161 MAKE_INSTR(HLT, 1, 0xf4);
162 MAKE_INSTR(CLTS, 2, 0x0f, 0x06);
163 MAKE_INSTR(LMSW, 3, 0x0f, 0x01, 0x00);
164 MAKE_INSTR(SMSW, 3, 0x0f, 0x01, 0x00);
167 #define PREFIX_LOCK 0xF0
168 #define PREFIX_REPNE 0xF2
169 #define PREFIX_REPNZ 0xF2
170 #define PREFIX_REP 0xF3
171 #define PREFIX_REPE 0xF3
172 #define PREFIX_REPZ 0xF3
173 #define PREFIX_CS_OVERRIDE 0x2E
174 #define PREFIX_SS_OVERRIDE 0x36
175 #define PREFIX_DS_OVERRIDE 0x3E
176 #define PREFIX_ES_OVERRIDE 0x26
177 #define PREFIX_FS_OVERRIDE 0x64
178 #define PREFIX_GS_OVERRIDE 0x65
179 #define PREFIX_BR_NOT_TAKEN 0x2E
180 #define PREFIX_BR_TAKEN 0x3E
181 #define PREFIX_OP_SIZE 0x66
182 #define PREFIX_ADDR_SIZE 0x67
184 static inline int is_prefix_byte(char byte) {
187 case 0xF2: // REPNE/REPNZ
188 case 0xF3: // REP or REPE/REPZ
189 case 0x2E: // CS override or Branch hint not taken (with Jcc instrs)
190 case 0x36: // SS override
191 case 0x3E: // DS override or Branch hint taken (with Jcc instrs)
192 case 0x26: // ES override
193 case 0x64: // FS override
194 case 0x65: // GS override
195 //case 0x2E: // branch not taken hint
196 // case 0x3E: // branch taken hint
197 case 0x66: // operand size override
198 case 0x67: // address size override
208 static inline v3_reg_t get_gpr_mask(struct guest_info * info) {
209 switch (info->cpu_mode) {
222 static inline addr_t get_addr_linear(struct guest_info * info, addr_t addr, struct v3_segment * seg) {
223 switch (info->cpu_mode) {
225 // It appears that the segment values are computed and cached in the vmcb structure
226 // We Need to check this for Intel
227 /* return addr + (seg->selector << 4);
231 return addr + seg->base;
240 typedef enum {INVALID_ADDR_TYPE, REG, DISP0, DISP8, DISP16, DISP32} modrm_mode_t;
241 typedef enum {INVALID_REG_SIZE, REG64, REG32, REG16, REG8} reg_size_t;
250 static inline addr_t decode_register(struct v3_gprs * gprs, char reg_code, reg_size_t reg_size) {
255 reg_addr = (addr_t)&(gprs->rax);
258 reg_addr = (addr_t)&(gprs->rcx);
261 reg_addr = (addr_t)&(gprs->rdx);
264 reg_addr = (addr_t)&(gprs->rbx);
267 if (reg_size == REG8) {
268 reg_addr = (addr_t)&(gprs->rax) + 1;
270 reg_addr = (addr_t)&(gprs->rsp);
274 if (reg_size == REG8) {
275 reg_addr = (addr_t)&(gprs->rcx) + 1;
277 reg_addr = (addr_t)&(gprs->rbp);
281 if (reg_size == REG8) {
282 reg_addr = (addr_t)&(gprs->rdx) + 1;
284 reg_addr = (addr_t)&(gprs->rsi);
288 if (reg_size == REG8) {
289 reg_addr = (addr_t)&(gprs->rbx) + 1;
291 reg_addr = (addr_t)&(gprs->rdi);
304 static inline operand_type_t decode_operands16(struct v3_gprs * gprs, // input/output
305 char * modrm_instr, // input
306 int * offset, // output
307 addr_t * first_operand, // output
308 addr_t * second_operand, // output
309 reg_size_t reg_size) { // input
311 struct modrm_byte * modrm = (struct modrm_byte *)modrm_instr;
312 addr_t base_addr = 0;
313 modrm_mode_t mod_mode = 0;
314 operand_type_t addr_type = INVALID_OPERAND;
315 char * instr_cursor = modrm_instr;
317 // PrintDebug("ModRM mod=%d\n", modrm->mod);
321 if (modrm->mod == 3) {
323 addr_type = REG_OPERAND;
324 //PrintDebug("first operand = Register (RM=%d)\n",modrm->rm);
326 *first_operand = decode_register(gprs, modrm->rm, reg_size);
330 addr_type = MEM_OPERAND;
332 if (modrm->mod == 0) {
334 } else if (modrm->mod == 1) {
336 } else if (modrm->mod == 2) {
342 base_addr = gprs->rbx + gprs->rsi;
345 base_addr = gprs->rbx + gprs->rdi;
348 base_addr = gprs->rbp + gprs->rsi;
351 base_addr = gprs->rbp + gprs->rdi;
354 base_addr = gprs->rsi;
357 base_addr = gprs->rdi;
360 if (modrm->mod == 0) {
364 base_addr = gprs->rbp;
368 base_addr = gprs->rbx;
374 if (mod_mode == DISP8) {
375 base_addr += (uchar_t)*(instr_cursor);
377 } else if (mod_mode == DISP16) {
378 base_addr += (ushort_t)*(instr_cursor);
382 *first_operand = base_addr;
385 *offset += (instr_cursor - modrm_instr);
386 *second_operand = decode_register(gprs, modrm->reg, reg_size);
393 static inline operand_type_t decode_operands32(struct v3_gprs * gprs, // input/output
394 char * modrm_instr, // input
395 int * offset, // output
396 addr_t * first_operand, // output
397 addr_t * second_operand, // output
398 reg_size_t reg_size) { // input
400 char * instr_cursor = modrm_instr;
401 struct modrm_byte * modrm = (struct modrm_byte *)modrm_instr;
402 addr_t base_addr = 0;
403 modrm_mode_t mod_mode = 0;
404 uint_t has_sib_byte = 0;
405 operand_type_t addr_type = INVALID_OPERAND;
411 if (modrm->mod == 3) {
413 addr_type = REG_OPERAND;
415 // PrintDebug("first operand = Register (RM=%d)\n",modrm->rm);
417 *first_operand = decode_register(gprs, modrm->rm, reg_size);
421 addr_type = MEM_OPERAND;
423 if (modrm->mod == 0) {
425 } else if (modrm->mod == 1) {
427 } else if (modrm->mod == 2) {
433 base_addr = gprs->rax;
436 base_addr = gprs->rcx;
439 base_addr = gprs->rdx;
442 base_addr = gprs->rbx;
448 if (modrm->mod == 0) {
452 base_addr = gprs->rbp;
456 base_addr = gprs->rsi;
459 base_addr = gprs->rdi;
465 struct sib_byte * sib = (struct sib_byte *)(instr_cursor);
471 if (sib->scale == 1) {
473 } else if (sib->scale == 2) {
475 } else if (sib->scale == 3) {
480 switch (sib->index) {
482 base_addr = gprs->rax;
485 base_addr = gprs->rcx;
488 base_addr = gprs->rdx;
491 base_addr = gprs->rbx;
497 base_addr = gprs->rbp;
500 base_addr = gprs->rsi;
503 base_addr = gprs->rdi;
512 base_addr += gprs->rax;
515 base_addr += gprs->rcx;
518 base_addr += gprs->rdx;
521 base_addr += gprs->rbx;
524 base_addr += gprs->rsp;
527 if (modrm->mod != 0) {
528 base_addr += gprs->rbp;
532 base_addr += gprs->rsi;
535 base_addr += gprs->rdi;
542 if (mod_mode == DISP8) {
543 base_addr += (uchar_t)*(instr_cursor);
545 } else if (mod_mode == DISP32) {
546 base_addr += (uint_t)*(instr_cursor);
551 *first_operand = base_addr;
554 *offset += (instr_cursor - modrm_instr);
556 *second_operand = decode_register(gprs, modrm->reg, reg_size);