bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 1 | /* |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 2 | * virtual page mapping and translated block handling |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 3 | * |
| 4 | * Copyright (c) 2003 Fabrice Bellard |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | #include <stdlib.h> |
| 21 | #include <stdio.h> |
| 22 | #include <stdarg.h> |
| 23 | #include <string.h> |
| 24 | #include <errno.h> |
| 25 | #include <unistd.h> |
| 26 | #include <inttypes.h> |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 27 | #include <sys/mman.h> |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 28 | |
| 29 | #include "cpu-i386.h" |
| 30 | |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 31 | //#define DEBUG_TB_INVALIDATE |
| 32 | #define DEBUG_FLUSH |
| 33 | |
| 34 | /* make various TB consistency checks */ |
| 35 | //#define DEBUG_TB_CHECK |
| 36 | |
| 37 | /* threshold to flush the translated code buffer */ |
| 38 | #define CODE_GEN_BUFFER_MAX_SIZE (CODE_GEN_BUFFER_SIZE - CODE_GEN_MAX_SIZE) |
| 39 | |
| 40 | #define CODE_GEN_MAX_BLOCKS (CODE_GEN_BUFFER_SIZE / 64) |
| 41 | |
| 42 | TranslationBlock tbs[CODE_GEN_MAX_BLOCKS]; |
| 43 | TranslationBlock *tb_hash[CODE_GEN_HASH_SIZE]; |
| 44 | int nb_tbs; |
bellard | eb51d10 | 2003-05-14 21:51:13 +0000 | [diff] [blame^] | 45 | /* any access to the tbs or the page table must use this lock */ |
| 46 | spinlock_t tb_lock = SPIN_LOCK_UNLOCKED; |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 47 | |
| 48 | uint8_t code_gen_buffer[CODE_GEN_BUFFER_SIZE]; |
| 49 | uint8_t *code_gen_ptr; |
| 50 | |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 51 | /* XXX: pack the flags in the low bits of the pointer ? */ |
| 52 | typedef struct PageDesc { |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 53 | unsigned long flags; |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 54 | TranslationBlock *first_tb; |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 55 | } PageDesc; |
| 56 | |
| 57 | #define L2_BITS 10 |
| 58 | #define L1_BITS (32 - L2_BITS - TARGET_PAGE_BITS) |
| 59 | |
| 60 | #define L1_SIZE (1 << L1_BITS) |
| 61 | #define L2_SIZE (1 << L2_BITS) |
| 62 | |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 63 | static void tb_invalidate_page(unsigned long address); |
| 64 | |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 65 | unsigned long real_host_page_size; |
| 66 | unsigned long host_page_bits; |
| 67 | unsigned long host_page_size; |
| 68 | unsigned long host_page_mask; |
| 69 | |
| 70 | static PageDesc *l1_map[L1_SIZE]; |
| 71 | |
| 72 | void page_init(void) |
| 73 | { |
| 74 | /* NOTE: we can always suppose that host_page_size >= |
| 75 | TARGET_PAGE_SIZE */ |
| 76 | real_host_page_size = getpagesize(); |
| 77 | if (host_page_size == 0) |
| 78 | host_page_size = real_host_page_size; |
| 79 | if (host_page_size < TARGET_PAGE_SIZE) |
| 80 | host_page_size = TARGET_PAGE_SIZE; |
| 81 | host_page_bits = 0; |
| 82 | while ((1 << host_page_bits) < host_page_size) |
| 83 | host_page_bits++; |
| 84 | host_page_mask = ~(host_page_size - 1); |
| 85 | } |
| 86 | |
| 87 | /* dump memory mappings */ |
| 88 | void page_dump(FILE *f) |
| 89 | { |
| 90 | unsigned long start, end; |
| 91 | int i, j, prot, prot1; |
| 92 | PageDesc *p; |
| 93 | |
| 94 | fprintf(f, "%-8s %-8s %-8s %s\n", |
| 95 | "start", "end", "size", "prot"); |
| 96 | start = -1; |
| 97 | end = -1; |
| 98 | prot = 0; |
| 99 | for(i = 0; i <= L1_SIZE; i++) { |
| 100 | if (i < L1_SIZE) |
| 101 | p = l1_map[i]; |
| 102 | else |
| 103 | p = NULL; |
| 104 | for(j = 0;j < L2_SIZE; j++) { |
| 105 | if (!p) |
| 106 | prot1 = 0; |
| 107 | else |
| 108 | prot1 = p[j].flags; |
| 109 | if (prot1 != prot) { |
| 110 | end = (i << (32 - L1_BITS)) | (j << TARGET_PAGE_BITS); |
| 111 | if (start != -1) { |
| 112 | fprintf(f, "%08lx-%08lx %08lx %c%c%c\n", |
| 113 | start, end, end - start, |
| 114 | prot & PAGE_READ ? 'r' : '-', |
| 115 | prot & PAGE_WRITE ? 'w' : '-', |
| 116 | prot & PAGE_EXEC ? 'x' : '-'); |
| 117 | } |
| 118 | if (prot1 != 0) |
| 119 | start = end; |
| 120 | else |
| 121 | start = -1; |
| 122 | prot = prot1; |
| 123 | } |
| 124 | if (!p) |
| 125 | break; |
| 126 | } |
| 127 | } |
| 128 | } |
| 129 | |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 130 | static inline PageDesc *page_find_alloc(unsigned int index) |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 131 | { |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 132 | PageDesc **lp, *p; |
| 133 | |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 134 | lp = &l1_map[index >> L2_BITS]; |
| 135 | p = *lp; |
| 136 | if (!p) { |
| 137 | /* allocate if not found */ |
| 138 | p = malloc(sizeof(PageDesc) * L2_SIZE); |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 139 | memset(p, 0, sizeof(PageDesc) * L2_SIZE); |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 140 | *lp = p; |
| 141 | } |
| 142 | return p + (index & (L2_SIZE - 1)); |
| 143 | } |
| 144 | |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 145 | static inline PageDesc *page_find(unsigned int index) |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 146 | { |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 147 | PageDesc *p; |
| 148 | |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 149 | p = l1_map[index >> L2_BITS]; |
| 150 | if (!p) |
| 151 | return 0; |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 152 | return p + (index & (L2_SIZE - 1)); |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 153 | } |
| 154 | |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 155 | int page_get_flags(unsigned long address) |
| 156 | { |
| 157 | PageDesc *p; |
| 158 | |
| 159 | p = page_find(address >> TARGET_PAGE_BITS); |
| 160 | if (!p) |
| 161 | return 0; |
| 162 | return p->flags; |
| 163 | } |
| 164 | |
| 165 | /* modify the flags of a page and invalidate the code if |
| 166 | necessary. The flag PAGE_WRITE_ORG is positionned automatically |
| 167 | depending on PAGE_WRITE */ |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 168 | void page_set_flags(unsigned long start, unsigned long end, int flags) |
| 169 | { |
| 170 | PageDesc *p; |
| 171 | unsigned long addr; |
| 172 | |
| 173 | start = start & TARGET_PAGE_MASK; |
| 174 | end = TARGET_PAGE_ALIGN(end); |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 175 | if (flags & PAGE_WRITE) |
| 176 | flags |= PAGE_WRITE_ORG; |
bellard | eb51d10 | 2003-05-14 21:51:13 +0000 | [diff] [blame^] | 177 | spin_lock(&tb_lock); |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 178 | for(addr = start; addr < end; addr += TARGET_PAGE_SIZE) { |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 179 | p = page_find_alloc(addr >> TARGET_PAGE_BITS); |
| 180 | /* if the write protection is set, then we invalidate the code |
| 181 | inside */ |
| 182 | if (!(p->flags & PAGE_WRITE) && |
| 183 | (flags & PAGE_WRITE) && |
| 184 | p->first_tb) { |
| 185 | tb_invalidate_page(addr); |
| 186 | } |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 187 | p->flags = flags; |
| 188 | } |
bellard | eb51d10 | 2003-05-14 21:51:13 +0000 | [diff] [blame^] | 189 | spin_unlock(&tb_lock); |
bellard | 5493600 | 2003-05-13 00:25:15 +0000 | [diff] [blame] | 190 | } |
bellard | fd6ce8f | 2003-05-14 19:00:11 +0000 | [diff] [blame] | 191 | |
| 192 | void cpu_x86_tblocks_init(void) |
| 193 | { |
| 194 | if (!code_gen_ptr) { |
| 195 | code_gen_ptr = code_gen_buffer; |
| 196 | } |
| 197 | } |
| 198 | |
| 199 | /* set to NULL all the 'first_tb' fields in all PageDescs */ |
| 200 | static void page_flush_tb(void) |
| 201 | { |
| 202 | int i, j; |
| 203 | PageDesc *p; |
| 204 | |
| 205 | for(i = 0; i < L1_SIZE; i++) { |
| 206 | p = l1_map[i]; |
| 207 | if (p) { |
| 208 | for(j = 0; j < L2_SIZE; j++) |
| 209 | p[j].first_tb = NULL; |
| 210 | } |
| 211 | } |
| 212 | } |
| 213 | |
| 214 | /* flush all the translation blocks */ |
| 215 | void tb_flush(void) |
| 216 | { |
| 217 | int i; |
| 218 | #ifdef DEBUG_FLUSH |
| 219 | printf("qemu: flush code_size=%d nb_tbs=%d avg_tb_size=%d\n", |
| 220 | code_gen_ptr - code_gen_buffer, |
| 221 | nb_tbs, |
| 222 | (code_gen_ptr - code_gen_buffer) / nb_tbs); |
| 223 | #endif |
| 224 | nb_tbs = 0; |
| 225 | for(i = 0;i < CODE_GEN_HASH_SIZE; i++) |
| 226 | tb_hash[i] = NULL; |
| 227 | page_flush_tb(); |
| 228 | code_gen_ptr = code_gen_buffer; |
| 229 | /* XXX: flush processor icache at this point */ |
| 230 | } |
| 231 | |
| 232 | #ifdef DEBUG_TB_CHECK |
| 233 | |
| 234 | static void tb_invalidate_check(unsigned long address) |
| 235 | { |
| 236 | TranslationBlock *tb; |
| 237 | int i; |
| 238 | address &= TARGET_PAGE_MASK; |
| 239 | for(i = 0;i < CODE_GEN_HASH_SIZE; i++) { |
| 240 | for(tb = tb_hash[i]; tb != NULL; tb = tb->hash_next) { |
| 241 | if (!(address + TARGET_PAGE_SIZE <= tb->pc || |
| 242 | address >= tb->pc + tb->size)) { |
| 243 | printf("ERROR invalidate: address=%08lx PC=%08lx size=%04x\n", |
| 244 | address, tb->pc, tb->size); |
| 245 | } |
| 246 | } |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | /* verify that all the pages have correct rights for code */ |
| 251 | static void tb_page_check(void) |
| 252 | { |
| 253 | TranslationBlock *tb; |
| 254 | int i, flags1, flags2; |
| 255 | |
| 256 | for(i = 0;i < CODE_GEN_HASH_SIZE; i++) { |
| 257 | for(tb = tb_hash[i]; tb != NULL; tb = tb->hash_next) { |
| 258 | flags1 = page_get_flags(tb->pc); |
| 259 | flags2 = page_get_flags(tb->pc + tb->size - 1); |
| 260 | if ((flags1 & PAGE_WRITE) || (flags2 & PAGE_WRITE)) { |
| 261 | printf("ERROR page flags: PC=%08lx size=%04x f1=%x f2=%x\n", |
| 262 | tb->pc, tb->size, flags1, flags2); |
| 263 | } |
| 264 | } |
| 265 | } |
| 266 | } |
| 267 | |
| 268 | #endif |
| 269 | |
| 270 | /* invalidate one TB */ |
| 271 | static inline void tb_remove(TranslationBlock **ptb, TranslationBlock *tb, |
| 272 | int next_offset) |
| 273 | { |
| 274 | TranslationBlock *tb1; |
| 275 | for(;;) { |
| 276 | tb1 = *ptb; |
| 277 | if (tb1 == tb) { |
| 278 | *ptb = *(TranslationBlock **)((char *)tb1 + next_offset); |
| 279 | break; |
| 280 | } |
| 281 | ptb = (TranslationBlock **)((char *)tb1 + next_offset); |
| 282 | } |
| 283 | } |
| 284 | |
| 285 | static inline void tb_invalidate(TranslationBlock *tb, int parity) |
| 286 | { |
| 287 | PageDesc *p; |
| 288 | unsigned int page_index1, page_index2; |
| 289 | unsigned int h; |
| 290 | |
| 291 | /* remove the TB from the hash list */ |
| 292 | h = tb_hash_func(tb->pc); |
| 293 | tb_remove(&tb_hash[h], tb, |
| 294 | offsetof(TranslationBlock, hash_next)); |
| 295 | /* remove the TB from the page list */ |
| 296 | page_index1 = tb->pc >> TARGET_PAGE_BITS; |
| 297 | if ((page_index1 & 1) == parity) { |
| 298 | p = page_find(page_index1); |
| 299 | tb_remove(&p->first_tb, tb, |
| 300 | offsetof(TranslationBlock, page_next[page_index1 & 1])); |
| 301 | } |
| 302 | page_index2 = (tb->pc + tb->size - 1) >> TARGET_PAGE_BITS; |
| 303 | if ((page_index2 & 1) == parity) { |
| 304 | p = page_find(page_index2); |
| 305 | tb_remove(&p->first_tb, tb, |
| 306 | offsetof(TranslationBlock, page_next[page_index2 & 1])); |
| 307 | } |
| 308 | } |
| 309 | |
| 310 | /* invalidate all TBs which intersect with the target page starting at addr */ |
| 311 | static void tb_invalidate_page(unsigned long address) |
| 312 | { |
| 313 | TranslationBlock *tb_next, *tb; |
| 314 | unsigned int page_index; |
| 315 | int parity1, parity2; |
| 316 | PageDesc *p; |
| 317 | #ifdef DEBUG_TB_INVALIDATE |
| 318 | printf("tb_invalidate_page: %lx\n", address); |
| 319 | #endif |
| 320 | |
| 321 | page_index = address >> TARGET_PAGE_BITS; |
| 322 | p = page_find(page_index); |
| 323 | if (!p) |
| 324 | return; |
| 325 | tb = p->first_tb; |
| 326 | parity1 = page_index & 1; |
| 327 | parity2 = parity1 ^ 1; |
| 328 | while (tb != NULL) { |
| 329 | tb_next = tb->page_next[parity1]; |
| 330 | tb_invalidate(tb, parity2); |
| 331 | tb = tb_next; |
| 332 | } |
| 333 | p->first_tb = NULL; |
| 334 | } |
| 335 | |
| 336 | /* add the tb in the target page and protect it if necessary */ |
| 337 | static inline void tb_alloc_page(TranslationBlock *tb, unsigned int page_index) |
| 338 | { |
| 339 | PageDesc *p; |
| 340 | unsigned long host_start, host_end, addr, page_addr; |
| 341 | int prot; |
| 342 | |
| 343 | p = page_find_alloc(page_index); |
| 344 | tb->page_next[page_index & 1] = p->first_tb; |
| 345 | p->first_tb = tb; |
| 346 | if (p->flags & PAGE_WRITE) { |
| 347 | /* force the host page as non writable (writes will have a |
| 348 | page fault + mprotect overhead) */ |
| 349 | page_addr = (page_index << TARGET_PAGE_BITS); |
| 350 | host_start = page_addr & host_page_mask; |
| 351 | host_end = host_start + host_page_size; |
| 352 | prot = 0; |
| 353 | for(addr = host_start; addr < host_end; addr += TARGET_PAGE_SIZE) |
| 354 | prot |= page_get_flags(addr); |
| 355 | mprotect((void *)host_start, host_page_size, |
| 356 | (prot & PAGE_BITS) & ~PAGE_WRITE); |
| 357 | #ifdef DEBUG_TB_INVALIDATE |
| 358 | printf("protecting code page: 0x%08lx\n", |
| 359 | host_start); |
| 360 | #endif |
| 361 | p->flags &= ~PAGE_WRITE; |
| 362 | #ifdef DEBUG_TB_CHECK |
| 363 | tb_page_check(); |
| 364 | #endif |
| 365 | } |
| 366 | } |
| 367 | |
| 368 | /* Allocate a new translation block. Flush the translation buffer if |
| 369 | too many translation blocks or too much generated code. */ |
| 370 | TranslationBlock *tb_alloc(unsigned long pc, |
| 371 | unsigned long size) |
| 372 | { |
| 373 | TranslationBlock *tb; |
| 374 | unsigned int page_index1, page_index2; |
| 375 | |
| 376 | if (nb_tbs >= CODE_GEN_MAX_BLOCKS || |
| 377 | (code_gen_ptr - code_gen_buffer) >= CODE_GEN_BUFFER_MAX_SIZE) |
| 378 | tb_flush(); |
| 379 | tb = &tbs[nb_tbs++]; |
| 380 | tb->pc = pc; |
| 381 | tb->size = size; |
| 382 | |
| 383 | /* add in the page list */ |
| 384 | page_index1 = pc >> TARGET_PAGE_BITS; |
| 385 | tb_alloc_page(tb, page_index1); |
| 386 | page_index2 = (pc + size - 1) >> TARGET_PAGE_BITS; |
| 387 | if (page_index2 != page_index1) { |
| 388 | tb_alloc_page(tb, page_index2); |
| 389 | } |
| 390 | return tb; |
| 391 | } |
| 392 | |
| 393 | /* called from signal handler: invalidate the code and unprotect the |
| 394 | page. Return TRUE if the fault was succesfully handled. */ |
| 395 | int page_unprotect(unsigned long address) |
| 396 | { |
| 397 | unsigned int page_index, prot; |
| 398 | PageDesc *p; |
| 399 | unsigned long host_start, host_end, addr; |
| 400 | |
| 401 | page_index = address >> TARGET_PAGE_BITS; |
| 402 | p = page_find(page_index); |
| 403 | if (!p) |
| 404 | return 0; |
| 405 | if ((p->flags & (PAGE_WRITE_ORG | PAGE_WRITE)) == PAGE_WRITE_ORG) { |
| 406 | /* if the page was really writable, then we change its |
| 407 | protection back to writable */ |
| 408 | host_start = address & host_page_mask; |
| 409 | host_end = host_start + host_page_size; |
| 410 | prot = 0; |
| 411 | for(addr = host_start; addr < host_end; addr += TARGET_PAGE_SIZE) |
| 412 | prot |= page_get_flags(addr); |
| 413 | mprotect((void *)host_start, host_page_size, |
| 414 | (prot & PAGE_BITS) | PAGE_WRITE); |
| 415 | p->flags |= PAGE_WRITE; |
| 416 | |
| 417 | /* and since the content will be modified, we must invalidate |
| 418 | the corresponding translated code. */ |
| 419 | tb_invalidate_page(address); |
| 420 | #ifdef DEBUG_TB_CHECK |
| 421 | tb_invalidate_check(address); |
| 422 | #endif |
| 423 | return 1; |
| 424 | } else { |
| 425 | return 0; |
| 426 | } |
| 427 | } |
| 428 | |
| 429 | /* call this function when system calls directly modify a memory area */ |
| 430 | void page_unprotect_range(uint8_t *data, unsigned long data_size) |
| 431 | { |
| 432 | unsigned long start, end, addr; |
| 433 | |
| 434 | start = (unsigned long)data; |
| 435 | end = start + data_size; |
| 436 | start &= TARGET_PAGE_MASK; |
| 437 | end = TARGET_PAGE_ALIGN(end); |
| 438 | for(addr = start; addr < end; addr += TARGET_PAGE_SIZE) { |
| 439 | page_unprotect(addr); |
| 440 | } |
| 441 | } |