1 /* vim:set shiftwidth=4 ts=4: */ 2 /* 3 * QEMU Block driver for virtual VFAT (shadows a local directory) 4 * 5 * Copyright (c) 2004,2005 Johannes E. Schindelin 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy 8 * of this software and associated documentation files (the "Software"), to deal 9 * in the Software without restriction, including without limitation the rights 10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 * copies of the Software, and to permit persons to whom the Software is 12 * furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in 15 * all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 23 * THE SOFTWARE. 24 */ 25 26 #include "qemu/osdep.h" 27 #include <dirent.h> 28 #include <glib/gstdio.h> 29 #include "qapi/error.h" 30 #include "block/block-io.h" 31 #include "block/block_int.h" 32 #include "block/qdict.h" 33 #include "qemu/module.h" 34 #include "qemu/option.h" 35 #include "qemu/bswap.h" 36 #include "migration/blocker.h" 37 #include "qapi/qmp/qdict.h" 38 #include "qapi/qmp/qstring.h" 39 #include "qemu/ctype.h" 40 #include "qemu/cutils.h" 41 #include "qemu/error-report.h" 42 43 #ifndef S_IWGRP 44 #define S_IWGRP 0 45 #endif 46 #ifndef S_IWOTH 47 #define S_IWOTH 0 48 #endif 49 50 /* TODO: add ":bootsector=blabla.img:" */ 51 /* LATER TODO: add automatic boot sector generation from 52 BOOTEASY.ASM and Ranish Partition Manager 53 Note that DOS assumes the system files to be the first files in the 54 file system (test if the boot sector still relies on that fact)! */ 55 /* MAYBE TODO: write block-visofs.c */ 56 /* TODO: call try_commit() only after a timeout */ 57 58 /* #define DEBUG */ 59 60 #ifdef DEBUG 61 62 #define DLOG(a) a 63 64 static void checkpoint(void); 65 66 #else 67 68 #define DLOG(a) 69 70 #endif 71 72 /* bootsector OEM name. see related compatibility problems at: 73 * https://jdebp.eu/FGA/volume-boot-block-oem-name-field.html 74 * http://seasip.info/Misc/oemid.html 75 */ 76 #define BOOTSECTOR_OEM_NAME "MSWIN4.1" 77 78 #define DIR_DELETED 0xe5 79 #define DIR_KANJI DIR_DELETED 80 #define DIR_KANJI_FAKE 0x05 81 #define DIR_FREE 0x00 82 83 /* dynamic array functions */ 84 typedef struct array_t { 85 char* pointer; 86 unsigned int size,next,item_size; 87 } array_t; 88 89 static inline void array_init(array_t* array,unsigned int item_size) 90 { 91 array->pointer = NULL; 92 array->size=0; 93 array->next=0; 94 array->item_size=item_size; 95 } 96 97 static inline void array_free(array_t* array) 98 { 99 g_free(array->pointer); 100 array->size=array->next=0; 101 } 102 103 /* does not automatically grow */ 104 static inline void* array_get(array_t* array,unsigned int index) { 105 assert(index < array->next); 106 assert(array->pointer); 107 return array->pointer + index * array->item_size; 108 } 109 110 static inline void array_ensure_allocated(array_t *array, int index) 111 { 112 if((index + 1) * array->item_size > array->size) { 113 int new_size = (index + 32) * array->item_size; 114 array->pointer = g_realloc(array->pointer, new_size); 115 assert(array->pointer); 116 memset(array->pointer + array->size, 0, new_size - array->size); 117 array->size = new_size; 118 array->next = index + 1; 119 } 120 } 121 122 static inline void* array_get_next(array_t* array) { 123 unsigned int next = array->next; 124 125 array_ensure_allocated(array, next); 126 array->next = next + 1; 127 return array_get(array, next); 128 } 129 130 static inline void* array_insert(array_t* array,unsigned int index,unsigned int count) { 131 if((array->next+count)*array->item_size>array->size) { 132 int increment=count*array->item_size; 133 array->pointer=g_realloc(array->pointer,array->size+increment); 134 if(!array->pointer) 135 return NULL; 136 array->size+=increment; 137 } 138 memmove(array->pointer+(index+count)*array->item_size, 139 array->pointer+index*array->item_size, 140 (array->next-index)*array->item_size); 141 array->next+=count; 142 return array->pointer+index*array->item_size; 143 } 144 145 static inline int array_remove_slice(array_t* array,int index, int count) 146 { 147 assert(index >=0); 148 assert(count > 0); 149 assert(index + count <= array->next); 150 151 memmove(array->pointer + index * array->item_size, 152 array->pointer + (index + count) * array->item_size, 153 (array->next - index - count) * array->item_size); 154 155 array->next -= count; 156 return 0; 157 } 158 159 static int array_remove(array_t* array,int index) 160 { 161 return array_remove_slice(array, index, 1); 162 } 163 164 /* return the index for a given member */ 165 static int array_index(array_t* array, void* pointer) 166 { 167 size_t offset = (char*)pointer - array->pointer; 168 assert((offset % array->item_size) == 0); 169 assert(offset/array->item_size < array->next); 170 return offset/array->item_size; 171 } 172 173 /* These structures are used to fake a disk and the VFAT filesystem. 174 * For this reason we need to use QEMU_PACKED. */ 175 176 typedef struct bootsector_t { 177 uint8_t jump[3]; 178 uint8_t name[8]; 179 uint16_t sector_size; 180 uint8_t sectors_per_cluster; 181 uint16_t reserved_sectors; 182 uint8_t number_of_fats; 183 uint16_t root_entries; 184 uint16_t total_sectors16; 185 uint8_t media_type; 186 uint16_t sectors_per_fat; 187 uint16_t sectors_per_track; 188 uint16_t number_of_heads; 189 uint32_t hidden_sectors; 190 uint32_t total_sectors; 191 union { 192 struct { 193 uint8_t drive_number; 194 uint8_t reserved1; 195 uint8_t signature; 196 uint32_t id; 197 uint8_t volume_label[11]; 198 uint8_t fat_type[8]; 199 uint8_t ignored[0x1c0]; 200 } QEMU_PACKED fat16; 201 struct { 202 uint32_t sectors_per_fat; 203 uint16_t flags; 204 uint8_t major,minor; 205 uint32_t first_cluster_of_root_dir; 206 uint16_t info_sector; 207 uint16_t backup_boot_sector; 208 uint8_t reserved[12]; 209 uint8_t drive_number; 210 uint8_t reserved1; 211 uint8_t signature; 212 uint32_t id; 213 uint8_t volume_label[11]; 214 uint8_t fat_type[8]; 215 uint8_t ignored[0x1a4]; 216 } QEMU_PACKED fat32; 217 } u; 218 uint8_t magic[2]; 219 } QEMU_PACKED bootsector_t; 220 221 typedef struct { 222 uint8_t head; 223 uint8_t sector; 224 uint8_t cylinder; 225 } mbr_chs_t; 226 227 typedef struct partition_t { 228 uint8_t attributes; /* 0x80 = bootable */ 229 mbr_chs_t start_CHS; 230 uint8_t fs_type; /* 0x1 = FAT12, 0x6 = FAT16, 0xe = FAT16_LBA, 0xb = FAT32, 0xc = FAT32_LBA */ 231 mbr_chs_t end_CHS; 232 uint32_t start_sector_long; 233 uint32_t length_sector_long; 234 } QEMU_PACKED partition_t; 235 236 typedef struct mbr_t { 237 uint8_t ignored[0x1b8]; 238 uint32_t nt_id; 239 uint8_t ignored2[2]; 240 partition_t partition[4]; 241 uint8_t magic[2]; 242 } QEMU_PACKED mbr_t; 243 244 typedef struct direntry_t { 245 uint8_t name[8 + 3]; 246 uint8_t attributes; 247 uint8_t reserved[2]; 248 uint16_t ctime; 249 uint16_t cdate; 250 uint16_t adate; 251 uint16_t begin_hi; 252 uint16_t mtime; 253 uint16_t mdate; 254 uint16_t begin; 255 uint32_t size; 256 } QEMU_PACKED direntry_t; 257 258 /* this structure are used to transparently access the files */ 259 260 typedef struct mapping_t { 261 /* begin is the first cluster, end is the last+1 */ 262 uint32_t begin,end; 263 /* as s->directory is growable, no pointer may be used here */ 264 unsigned int dir_index; 265 /* the clusters of a file may be in any order; this points to the first */ 266 int first_mapping_index; 267 union { 268 /* offset is 269 * - the offset in the file (in clusters) for a file, or 270 * - the next cluster of the directory for a directory 271 */ 272 struct { 273 uint32_t offset; 274 } file; 275 struct { 276 int parent_mapping_index; 277 int first_dir_index; 278 } dir; 279 } info; 280 /* path contains the full path, i.e. it always starts with s->path */ 281 char* path; 282 283 enum { 284 MODE_UNDEFINED = 0, 285 MODE_NORMAL = 1, 286 MODE_MODIFIED = 2, 287 MODE_DIRECTORY = 4, 288 MODE_DELETED = 8, 289 } mode; 290 int read_only; 291 } mapping_t; 292 293 #ifdef DEBUG 294 static void print_direntry(const struct direntry_t*); 295 static void print_mapping(const struct mapping_t* mapping); 296 #endif 297 298 /* here begins the real VVFAT driver */ 299 300 typedef struct BDRVVVFATState { 301 CoMutex lock; 302 BlockDriverState* bs; /* pointer to parent */ 303 unsigned char first_sectors[0x40*0x200]; 304 305 int fat_type; /* 16 or 32 */ 306 array_t fat,directory,mapping; 307 char volume_label[11]; 308 309 uint32_t offset_to_bootsector; /* 0 for floppy, 0x3f for disk */ 310 311 unsigned int cluster_size; 312 unsigned int sectors_per_cluster; 313 unsigned int sectors_per_fat; 314 uint32_t last_cluster_of_root_directory; 315 /* how many entries are available in root directory (0 for FAT32) */ 316 uint16_t root_entries; 317 uint32_t sector_count; /* total number of sectors of the partition */ 318 uint32_t cluster_count; /* total number of clusters of this partition */ 319 uint32_t max_fat_value; 320 uint32_t offset_to_fat; 321 uint32_t offset_to_root_dir; 322 323 int current_fd; 324 mapping_t* current_mapping; 325 unsigned char* cluster; /* points to current cluster */ 326 unsigned char* cluster_buffer; /* points to a buffer to hold temp data */ 327 unsigned int current_cluster; 328 329 /* write support */ 330 char* qcow_filename; 331 BdrvChild* qcow; 332 void* fat2; 333 char* used_clusters; 334 array_t commits; 335 const char* path; 336 int downcase_short_names; 337 338 Error *migration_blocker; 339 } BDRVVVFATState; 340 341 /* take the sector position spos and convert it to Cylinder/Head/Sector position 342 * if the position is outside the specified geometry, fill maximum value for CHS 343 * and return 1 to signal overflow. 344 */ 345 static int sector2CHS(mbr_chs_t *chs, int spos, int cyls, int heads, int secs) 346 { 347 int head,sector; 348 sector = spos % secs; spos /= secs; 349 head = spos % heads; spos /= heads; 350 if (spos >= cyls) { 351 /* Overflow, 352 it happens if 32bit sector positions are used, while CHS is only 24bit. 353 Windows/Dos is said to take 1023/255/63 as nonrepresentable CHS */ 354 chs->head = 0xFF; 355 chs->sector = 0xFF; 356 chs->cylinder = 0xFF; 357 return 1; 358 } 359 chs->head = (uint8_t)head; 360 chs->sector = (uint8_t)( (sector+1) | ((spos>>8)<<6) ); 361 chs->cylinder = (uint8_t)spos; 362 return 0; 363 } 364 365 static void init_mbr(BDRVVVFATState *s, int cyls, int heads, int secs) 366 { 367 /* TODO: if the files mbr.img and bootsect.img exist, use them */ 368 mbr_t* real_mbr=(mbr_t*)s->first_sectors; 369 partition_t* partition = &(real_mbr->partition[0]); 370 int lba; 371 372 memset(s->first_sectors,0,512); 373 374 /* Win NT Disk Signature */ 375 real_mbr->nt_id= cpu_to_le32(0xbe1afdfa); 376 377 partition->attributes=0x80; /* bootable */ 378 379 /* LBA is used when partition is outside the CHS geometry */ 380 lba = sector2CHS(&partition->start_CHS, s->offset_to_bootsector, 381 cyls, heads, secs); 382 lba |= sector2CHS(&partition->end_CHS, s->bs->total_sectors - 1, 383 cyls, heads, secs); 384 385 /*LBA partitions are identified only by start/length_sector_long not by CHS*/ 386 partition->start_sector_long = cpu_to_le32(s->offset_to_bootsector); 387 partition->length_sector_long = cpu_to_le32(s->bs->total_sectors 388 - s->offset_to_bootsector); 389 390 /* FAT12/FAT16/FAT32 */ 391 /* DOS uses different types when partition is LBA, 392 probably to prevent older versions from using CHS on them */ 393 partition->fs_type = s->fat_type == 12 ? 0x1 : 394 s->fat_type == 16 ? (lba ? 0xe : 0x06) : 395 /*s->fat_type == 32*/ (lba ? 0xc : 0x0b); 396 397 real_mbr->magic[0]=0x55; real_mbr->magic[1]=0xaa; 398 } 399 400 /* direntry functions */ 401 402 static direntry_t *create_long_filename(BDRVVVFATState *s, const char *filename) 403 { 404 int number_of_entries, i; 405 glong length; 406 direntry_t *entry; 407 408 gunichar2 *longname = g_utf8_to_utf16(filename, -1, NULL, &length, NULL); 409 if (!longname) { 410 fprintf(stderr, "vvfat: invalid UTF-8 name: %s\n", filename); 411 return NULL; 412 } 413 414 number_of_entries = DIV_ROUND_UP(length * 2, 26); 415 416 for(i=0;i<number_of_entries;i++) { 417 entry=array_get_next(&(s->directory)); 418 entry->attributes=0xf; 419 entry->reserved[0]=0; 420 entry->begin=0; 421 entry->name[0]=(number_of_entries-i)|(i==0?0x40:0); 422 } 423 for(i=0;i<26*number_of_entries;i++) { 424 int offset=(i%26); 425 if(offset<10) offset=1+offset; 426 else if(offset<22) offset=14+offset-10; 427 else offset=28+offset-22; 428 entry=array_get(&(s->directory),s->directory.next-1-(i/26)); 429 if (i >= 2 * length + 2) { 430 entry->name[offset] = 0xff; 431 } else if (i % 2 == 0) { 432 entry->name[offset] = longname[i / 2] & 0xff; 433 } else { 434 entry->name[offset] = longname[i / 2] >> 8; 435 } 436 } 437 g_free(longname); 438 return array_get(&(s->directory),s->directory.next-number_of_entries); 439 } 440 441 static char is_free(const direntry_t* direntry) 442 { 443 return direntry->name[0] == DIR_DELETED || direntry->name[0] == DIR_FREE; 444 } 445 446 static char is_volume_label(const direntry_t* direntry) 447 { 448 return direntry->attributes == 0x28; 449 } 450 451 static char is_long_name(const direntry_t* direntry) 452 { 453 return direntry->attributes == 0xf; 454 } 455 456 static char is_short_name(const direntry_t* direntry) 457 { 458 return !is_volume_label(direntry) && !is_long_name(direntry) 459 && !is_free(direntry); 460 } 461 462 static char is_directory(const direntry_t* direntry) 463 { 464 return direntry->attributes & 0x10 && direntry->name[0] != DIR_DELETED; 465 } 466 467 static inline char is_dot(const direntry_t* direntry) 468 { 469 return is_short_name(direntry) && direntry->name[0] == '.'; 470 } 471 472 static char is_file(const direntry_t* direntry) 473 { 474 return is_short_name(direntry) && !is_directory(direntry); 475 } 476 477 static inline uint32_t begin_of_direntry(const direntry_t* direntry) 478 { 479 return le16_to_cpu(direntry->begin)|(le16_to_cpu(direntry->begin_hi)<<16); 480 } 481 482 static inline uint32_t filesize_of_direntry(const direntry_t* direntry) 483 { 484 return le32_to_cpu(direntry->size); 485 } 486 487 static void set_begin_of_direntry(direntry_t* direntry, uint32_t begin) 488 { 489 direntry->begin = cpu_to_le16(begin & 0xffff); 490 direntry->begin_hi = cpu_to_le16((begin >> 16) & 0xffff); 491 } 492 493 static bool valid_filename(const unsigned char *name) 494 { 495 unsigned char c; 496 if (!strcmp((const char*)name, ".") || !strcmp((const char*)name, "..")) { 497 return false; 498 } 499 for (; (c = *name); name++) { 500 if (!((c >= '0' && c <= '9') || 501 (c >= 'A' && c <= 'Z') || 502 (c >= 'a' && c <= 'z') || 503 c > 127 || 504 strchr(" $%'-_@~`!(){}^#&.+,;=[]", c) != NULL)) 505 { 506 return false; 507 } 508 } 509 return true; 510 } 511 512 static uint8_t to_valid_short_char(gunichar c) 513 { 514 c = g_unichar_toupper(c); 515 if ((c >= '0' && c <= '9') || 516 (c >= 'A' && c <= 'Z') || 517 strchr("$%'-_@~`!(){}^#&", c) != NULL) { 518 return c; 519 } else { 520 return 0; 521 } 522 } 523 524 static direntry_t *create_short_filename(BDRVVVFATState *s, 525 const char *filename, 526 unsigned int directory_start) 527 { 528 int i, j = 0; 529 direntry_t *entry = array_get_next(&(s->directory)); 530 const gchar *p, *last_dot = NULL; 531 gunichar c; 532 bool lossy_conversion = false; 533 char tail[8]; 534 535 if (!entry) { 536 return NULL; 537 } 538 memset(entry->name, 0x20, sizeof(entry->name)); 539 540 /* copy filename and search last dot */ 541 for (p = filename; ; p = g_utf8_next_char(p)) { 542 c = g_utf8_get_char(p); 543 if (c == '\0') { 544 break; 545 } else if (c == '.') { 546 if (j == 0) { 547 /* '.' at start of filename */ 548 lossy_conversion = true; 549 } else { 550 if (last_dot) { 551 lossy_conversion = true; 552 } 553 last_dot = p; 554 } 555 } else if (!last_dot) { 556 /* first part of the name; copy it */ 557 uint8_t v = to_valid_short_char(c); 558 if (j < 8 && v) { 559 entry->name[j++] = v; 560 } else { 561 lossy_conversion = true; 562 } 563 } 564 } 565 566 /* copy extension (if any) */ 567 if (last_dot) { 568 j = 0; 569 for (p = g_utf8_next_char(last_dot); ; p = g_utf8_next_char(p)) { 570 c = g_utf8_get_char(p); 571 if (c == '\0') { 572 break; 573 } else { 574 /* extension; copy it */ 575 uint8_t v = to_valid_short_char(c); 576 if (j < 3 && v) { 577 entry->name[8 + (j++)] = v; 578 } else { 579 lossy_conversion = true; 580 } 581 } 582 } 583 } 584 585 if (entry->name[0] == DIR_KANJI) { 586 entry->name[0] = DIR_KANJI_FAKE; 587 } 588 589 /* numeric-tail generation */ 590 for (j = 0; j < 8; j++) { 591 if (entry->name[j] == ' ') { 592 break; 593 } 594 } 595 for (i = lossy_conversion ? 1 : 0; i < 999999; i++) { 596 direntry_t *entry1; 597 if (i > 0) { 598 int len = snprintf(tail, sizeof(tail), "~%u", (unsigned)i); 599 assert(len <= 7); 600 memcpy(entry->name + MIN(j, 8 - len), tail, len); 601 } 602 for (entry1 = array_get(&(s->directory), directory_start); 603 entry1 < entry; entry1++) { 604 if (!is_long_name(entry1) && 605 !memcmp(entry1->name, entry->name, 11)) { 606 break; /* found dupe */ 607 } 608 } 609 if (entry1 == entry) { 610 /* no dupe found */ 611 return entry; 612 } 613 } 614 return NULL; 615 } 616 617 /* fat functions */ 618 619 static inline uint8_t fat_chksum(const direntry_t* entry) 620 { 621 uint8_t chksum=0; 622 int i; 623 624 for (i = 0; i < ARRAY_SIZE(entry->name); i++) { 625 chksum = (((chksum & 0xfe) >> 1) | 626 ((chksum & 0x01) ? 0x80 : 0)) + entry->name[i]; 627 } 628 629 return chksum; 630 } 631 632 /* if return_time==0, this returns the fat_date, else the fat_time */ 633 static uint16_t fat_datetime(time_t time,int return_time) { 634 struct tm* t; 635 struct tm t1; 636 t = &t1; 637 localtime_r(&time,t); 638 if(return_time) 639 return cpu_to_le16((t->tm_sec/2)|(t->tm_min<<5)|(t->tm_hour<<11)); 640 return cpu_to_le16((t->tm_mday)|((t->tm_mon+1)<<5)|((t->tm_year-80)<<9)); 641 } 642 643 static inline void fat_set(BDRVVVFATState* s,unsigned int cluster,uint32_t value) 644 { 645 if(s->fat_type==32) { 646 uint32_t* entry=array_get(&(s->fat),cluster); 647 *entry=cpu_to_le32(value); 648 } else if(s->fat_type==16) { 649 uint16_t* entry=array_get(&(s->fat),cluster); 650 *entry=cpu_to_le16(value&0xffff); 651 } else { 652 int offset = (cluster*3/2); 653 unsigned char* p = array_get(&(s->fat), offset); 654 switch (cluster&1) { 655 case 0: 656 p[0] = value&0xff; 657 p[1] = (p[1]&0xf0) | ((value>>8)&0xf); 658 break; 659 case 1: 660 p[0] = (p[0]&0xf) | ((value&0xf)<<4); 661 p[1] = (value>>4); 662 break; 663 } 664 } 665 } 666 667 static inline uint32_t fat_get(BDRVVVFATState* s,unsigned int cluster) 668 { 669 if(s->fat_type==32) { 670 uint32_t* entry=array_get(&(s->fat),cluster); 671 return le32_to_cpu(*entry); 672 } else if(s->fat_type==16) { 673 uint16_t* entry=array_get(&(s->fat),cluster); 674 return le16_to_cpu(*entry); 675 } else { 676 const uint8_t* x=(uint8_t*)(s->fat.pointer)+cluster*3/2; 677 return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff; 678 } 679 } 680 681 static inline int fat_eof(BDRVVVFATState* s,uint32_t fat_entry) 682 { 683 if(fat_entry>s->max_fat_value-8) 684 return -1; 685 return 0; 686 } 687 688 static inline void init_fat(BDRVVVFATState* s) 689 { 690 if (s->fat_type == 12) { 691 array_init(&(s->fat),1); 692 array_ensure_allocated(&(s->fat), 693 s->sectors_per_fat * 0x200 * 3 / 2 - 1); 694 } else { 695 array_init(&(s->fat),(s->fat_type==32?4:2)); 696 array_ensure_allocated(&(s->fat), 697 s->sectors_per_fat * 0x200 / s->fat.item_size - 1); 698 } 699 memset(s->fat.pointer,0,s->fat.size); 700 701 switch(s->fat_type) { 702 case 12: s->max_fat_value=0xfff; break; 703 case 16: s->max_fat_value=0xffff; break; 704 case 32: s->max_fat_value=0x0fffffff; break; 705 default: s->max_fat_value=0; /* error... */ 706 } 707 708 } 709 710 static inline direntry_t* create_short_and_long_name(BDRVVVFATState* s, 711 unsigned int directory_start, const char* filename, int is_dot) 712 { 713 int long_index = s->directory.next; 714 direntry_t* entry = NULL; 715 direntry_t* entry_long = NULL; 716 717 if(is_dot) { 718 entry=array_get_next(&(s->directory)); 719 memset(entry->name, 0x20, sizeof(entry->name)); 720 memcpy(entry->name,filename,strlen(filename)); 721 return entry; 722 } 723 724 entry_long=create_long_filename(s,filename); 725 entry = create_short_filename(s, filename, directory_start); 726 727 /* calculate checksum; propagate to long name */ 728 if(entry_long) { 729 uint8_t chksum=fat_chksum(entry); 730 731 /* calculate anew, because realloc could have taken place */ 732 entry_long=array_get(&(s->directory),long_index); 733 while(entry_long<entry && is_long_name(entry_long)) { 734 entry_long->reserved[1]=chksum; 735 entry_long++; 736 } 737 } 738 739 return entry; 740 } 741 742 /* 743 * Read a directory. (the index of the corresponding mapping must be passed). 744 */ 745 static int read_directory(BDRVVVFATState* s, int mapping_index) 746 { 747 mapping_t* mapping = array_get(&(s->mapping), mapping_index); 748 direntry_t* direntry; 749 const char* dirname = mapping->path; 750 int first_cluster = mapping->begin; 751 int parent_index = mapping->info.dir.parent_mapping_index; 752 mapping_t* parent_mapping = (mapping_t*) 753 (parent_index >= 0 ? array_get(&(s->mapping), parent_index) : NULL); 754 int first_cluster_of_parent = parent_mapping ? parent_mapping->begin : -1; 755 756 DIR* dir=opendir(dirname); 757 struct dirent* entry; 758 int i; 759 760 assert(mapping->mode & MODE_DIRECTORY); 761 762 if(!dir) { 763 mapping->end = mapping->begin; 764 return -1; 765 } 766 767 i = mapping->info.dir.first_dir_index = 768 first_cluster == 0 ? 0 : s->directory.next; 769 770 if (first_cluster != 0) { 771 /* create the top entries of a subdirectory */ 772 (void)create_short_and_long_name(s, i, ".", 1); 773 (void)create_short_and_long_name(s, i, "..", 1); 774 } 775 776 /* actually read the directory, and allocate the mappings */ 777 while((entry=readdir(dir))) { 778 unsigned int length=strlen(dirname)+2+strlen(entry->d_name); 779 char* buffer; 780 struct stat st; 781 int is_dot=!strcmp(entry->d_name,"."); 782 int is_dotdot=!strcmp(entry->d_name,".."); 783 784 if (first_cluster == 0 && s->directory.next >= s->root_entries - 1) { 785 fprintf(stderr, "Too many entries in root directory\n"); 786 closedir(dir); 787 return -2; 788 } 789 790 if(first_cluster == 0 && (is_dotdot || is_dot)) 791 continue; 792 793 buffer = g_malloc(length); 794 snprintf(buffer,length,"%s/%s",dirname,entry->d_name); 795 796 if(stat(buffer,&st)<0) { 797 g_free(buffer); 798 continue; 799 } 800 801 /* create directory entry for this file */ 802 if (!is_dot && !is_dotdot) { 803 direntry = create_short_and_long_name(s, i, entry->d_name, 0); 804 } else { 805 direntry = array_get(&(s->directory), is_dot ? i : i + 1); 806 } 807 direntry->attributes=(S_ISDIR(st.st_mode)?0x10:0x20); 808 direntry->reserved[0]=direntry->reserved[1]=0; 809 direntry->ctime=fat_datetime(st.st_ctime,1); 810 direntry->cdate=fat_datetime(st.st_ctime,0); 811 direntry->adate=fat_datetime(st.st_atime,0); 812 direntry->begin_hi=0; 813 direntry->mtime=fat_datetime(st.st_mtime,1); 814 direntry->mdate=fat_datetime(st.st_mtime,0); 815 if(is_dotdot) 816 set_begin_of_direntry(direntry, first_cluster_of_parent); 817 else if(is_dot) 818 set_begin_of_direntry(direntry, first_cluster); 819 else 820 direntry->begin=0; /* do that later */ 821 if (st.st_size > 0x7fffffff) { 822 fprintf(stderr, "File %s is larger than 2GB\n", buffer); 823 g_free(buffer); 824 closedir(dir); 825 return -2; 826 } 827 direntry->size=cpu_to_le32(S_ISDIR(st.st_mode)?0:st.st_size); 828 829 /* create mapping for this file */ 830 if(!is_dot && !is_dotdot && (S_ISDIR(st.st_mode) || st.st_size)) { 831 s->current_mapping = array_get_next(&(s->mapping)); 832 s->current_mapping->begin=0; 833 s->current_mapping->end=st.st_size; 834 /* 835 * we get the direntry of the most recent direntry, which 836 * contains the short name and all the relevant information. 837 */ 838 s->current_mapping->dir_index=s->directory.next-1; 839 s->current_mapping->first_mapping_index = -1; 840 if (S_ISDIR(st.st_mode)) { 841 s->current_mapping->mode = MODE_DIRECTORY; 842 s->current_mapping->info.dir.parent_mapping_index = 843 mapping_index; 844 } else { 845 s->current_mapping->mode = MODE_UNDEFINED; 846 s->current_mapping->info.file.offset = 0; 847 } 848 s->current_mapping->path=buffer; 849 s->current_mapping->read_only = 850 (st.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) == 0; 851 } else { 852 g_free(buffer); 853 } 854 } 855 closedir(dir); 856 857 /* fill with zeroes up to the end of the cluster */ 858 while(s->directory.next%(0x10*s->sectors_per_cluster)) { 859 direntry = array_get_next(&(s->directory)); 860 memset(direntry,0,sizeof(direntry_t)); 861 } 862 863 if (s->fat_type != 32 && 864 mapping_index == 0 && 865 s->directory.next < s->root_entries) { 866 /* root directory */ 867 int cur = s->directory.next; 868 array_ensure_allocated(&(s->directory), s->root_entries - 1); 869 s->directory.next = s->root_entries; 870 memset(array_get(&(s->directory), cur), 0, 871 (s->root_entries - cur) * sizeof(direntry_t)); 872 } 873 874 /* re-get the mapping, since s->mapping was possibly realloc()ed */ 875 mapping = array_get(&(s->mapping), mapping_index); 876 first_cluster += (s->directory.next - mapping->info.dir.first_dir_index) 877 * 0x20 / s->cluster_size; 878 mapping->end = first_cluster; 879 880 direntry = array_get(&(s->directory), mapping->dir_index); 881 set_begin_of_direntry(direntry, mapping->begin); 882 883 return 0; 884 } 885 886 static inline int32_t sector2cluster(BDRVVVFATState* s,off_t sector_num) 887 { 888 return (sector_num - s->offset_to_root_dir) / s->sectors_per_cluster; 889 } 890 891 static inline off_t cluster2sector(BDRVVVFATState* s, uint32_t cluster_num) 892 { 893 return s->offset_to_root_dir + s->sectors_per_cluster * cluster_num; 894 } 895 896 static int init_directories(BDRVVVFATState* s, 897 const char *dirname, int heads, int secs, 898 Error **errp) 899 { 900 bootsector_t* bootsector; 901 mapping_t* mapping; 902 unsigned int i; 903 unsigned int cluster; 904 905 memset(&(s->first_sectors[0]),0,0x40*0x200); 906 907 s->cluster_size=s->sectors_per_cluster*0x200; 908 s->cluster_buffer=g_malloc(s->cluster_size); 909 910 /* 911 * The formula: sc = spf+1+spf*spc*(512*8/fat_type), 912 * where sc is sector_count, 913 * spf is sectors_per_fat, 914 * spc is sectors_per_clusters, and 915 * fat_type = 12, 16 or 32. 916 */ 917 i = 1+s->sectors_per_cluster*0x200*8/s->fat_type; 918 s->sectors_per_fat=(s->sector_count+i)/i; /* round up */ 919 920 s->offset_to_fat = s->offset_to_bootsector + 1; 921 s->offset_to_root_dir = s->offset_to_fat + s->sectors_per_fat * 2; 922 923 array_init(&(s->mapping),sizeof(mapping_t)); 924 array_init(&(s->directory),sizeof(direntry_t)); 925 926 /* add volume label */ 927 { 928 direntry_t* entry=array_get_next(&(s->directory)); 929 entry->attributes=0x28; /* archive | volume label */ 930 memcpy(entry->name, s->volume_label, sizeof(entry->name)); 931 } 932 933 /* Now build FAT, and write back information into directory */ 934 init_fat(s); 935 936 /* TODO: if there are more entries, bootsector has to be adjusted! */ 937 s->root_entries = 0x02 * 0x10 * s->sectors_per_cluster; 938 s->cluster_count=sector2cluster(s, s->sector_count); 939 940 mapping = array_get_next(&(s->mapping)); 941 mapping->begin = 0; 942 mapping->dir_index = 0; 943 mapping->info.dir.parent_mapping_index = -1; 944 mapping->first_mapping_index = -1; 945 mapping->path = g_strdup(dirname); 946 i = strlen(mapping->path); 947 if (i > 0 && mapping->path[i - 1] == '/') 948 mapping->path[i - 1] = '\0'; 949 mapping->mode = MODE_DIRECTORY; 950 mapping->read_only = 0; 951 s->path = mapping->path; 952 953 for (i = 0, cluster = 0; i < s->mapping.next; i++) { 954 /* MS-DOS expects the FAT to be 0 for the root directory 955 * (except for the media byte). */ 956 /* LATER TODO: still true for FAT32? */ 957 int fix_fat = (i != 0); 958 mapping = array_get(&(s->mapping), i); 959 960 if (mapping->mode & MODE_DIRECTORY) { 961 char *path = mapping->path; 962 mapping->begin = cluster; 963 if(read_directory(s, i)) { 964 error_setg(errp, "Could not read directory %s", path); 965 return -1; 966 } 967 mapping = array_get(&(s->mapping), i); 968 } else { 969 assert(mapping->mode == MODE_UNDEFINED); 970 mapping->mode=MODE_NORMAL; 971 mapping->begin = cluster; 972 if (mapping->end > 0) { 973 direntry_t* direntry = array_get(&(s->directory), 974 mapping->dir_index); 975 976 mapping->end = cluster + 1 + (mapping->end-1)/s->cluster_size; 977 set_begin_of_direntry(direntry, mapping->begin); 978 } else { 979 mapping->end = cluster + 1; 980 fix_fat = 0; 981 } 982 } 983 984 assert(mapping->begin < mapping->end); 985 986 /* next free cluster */ 987 cluster = mapping->end; 988 989 if(cluster > s->cluster_count) { 990 error_setg(errp, 991 "Directory does not fit in FAT%d (capacity %.2f MB)", 992 s->fat_type, s->sector_count / 2000.0); 993 return -1; 994 } 995 996 /* fix fat for entry */ 997 if (fix_fat) { 998 int j; 999 for(j = mapping->begin; j < mapping->end - 1; j++) 1000 fat_set(s, j, j+1); 1001 fat_set(s, mapping->end - 1, s->max_fat_value); 1002 } 1003 } 1004 1005 mapping = array_get(&(s->mapping), 0); 1006 s->last_cluster_of_root_directory = mapping->end; 1007 1008 /* the FAT signature */ 1009 fat_set(s,0,s->max_fat_value); 1010 fat_set(s,1,s->max_fat_value); 1011 1012 s->current_mapping = NULL; 1013 1014 bootsector = (bootsector_t *)(s->first_sectors 1015 + s->offset_to_bootsector * 0x200); 1016 bootsector->jump[0]=0xeb; 1017 bootsector->jump[1]=0x3e; 1018 bootsector->jump[2]=0x90; 1019 memcpy(bootsector->name, BOOTSECTOR_OEM_NAME, 8); 1020 bootsector->sector_size=cpu_to_le16(0x200); 1021 bootsector->sectors_per_cluster=s->sectors_per_cluster; 1022 bootsector->reserved_sectors=cpu_to_le16(1); 1023 bootsector->number_of_fats=0x2; /* number of FATs */ 1024 bootsector->root_entries = cpu_to_le16(s->root_entries); 1025 bootsector->total_sectors16=s->sector_count>0xffff?0:cpu_to_le16(s->sector_count); 1026 /* media descriptor: hard disk=0xf8, floppy=0xf0 */ 1027 bootsector->media_type = (s->offset_to_bootsector > 0 ? 0xf8 : 0xf0); 1028 s->fat.pointer[0] = bootsector->media_type; 1029 bootsector->sectors_per_fat=cpu_to_le16(s->sectors_per_fat); 1030 bootsector->sectors_per_track = cpu_to_le16(secs); 1031 bootsector->number_of_heads = cpu_to_le16(heads); 1032 bootsector->hidden_sectors = cpu_to_le32(s->offset_to_bootsector); 1033 bootsector->total_sectors=cpu_to_le32(s->sector_count>0xffff?s->sector_count:0); 1034 1035 /* LATER TODO: if FAT32, this is wrong */ 1036 /* drive_number: fda=0, hda=0x80 */ 1037 bootsector->u.fat16.drive_number = s->offset_to_bootsector == 0 ? 0 : 0x80; 1038 bootsector->u.fat16.signature=0x29; 1039 bootsector->u.fat16.id=cpu_to_le32(0xfabe1afd); 1040 1041 memcpy(bootsector->u.fat16.volume_label, s->volume_label, 1042 sizeof(bootsector->u.fat16.volume_label)); 1043 memcpy(bootsector->u.fat16.fat_type, 1044 s->fat_type == 12 ? "FAT12 " : "FAT16 ", 8); 1045 bootsector->magic[0]=0x55; bootsector->magic[1]=0xaa; 1046 1047 return 0; 1048 } 1049 1050 #ifdef DEBUG 1051 static BDRVVVFATState *vvv = NULL; 1052 #endif 1053 1054 static int enable_write_target(BlockDriverState *bs, Error **errp); 1055 static int coroutine_fn is_consistent(BDRVVVFATState *s); 1056 1057 static QemuOptsList runtime_opts = { 1058 .name = "vvfat", 1059 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 1060 .desc = { 1061 { 1062 .name = "dir", 1063 .type = QEMU_OPT_STRING, 1064 .help = "Host directory to map to the vvfat device", 1065 }, 1066 { 1067 .name = "fat-type", 1068 .type = QEMU_OPT_NUMBER, 1069 .help = "FAT type (12, 16 or 32)", 1070 }, 1071 { 1072 .name = "floppy", 1073 .type = QEMU_OPT_BOOL, 1074 .help = "Create a floppy rather than a hard disk image", 1075 }, 1076 { 1077 .name = "label", 1078 .type = QEMU_OPT_STRING, 1079 .help = "Use a volume label other than QEMU VVFAT", 1080 }, 1081 { 1082 .name = "rw", 1083 .type = QEMU_OPT_BOOL, 1084 .help = "Make the image writable", 1085 }, 1086 { /* end of list */ } 1087 }, 1088 }; 1089 1090 static void vvfat_parse_filename(const char *filename, QDict *options, 1091 Error **errp) 1092 { 1093 int fat_type = 0; 1094 bool floppy = false; 1095 bool rw = false; 1096 int i; 1097 1098 if (!strstart(filename, "fat:", NULL)) { 1099 error_setg(errp, "File name string must start with 'fat:'"); 1100 return; 1101 } 1102 1103 /* Parse options */ 1104 if (strstr(filename, ":32:")) { 1105 fat_type = 32; 1106 } else if (strstr(filename, ":16:")) { 1107 fat_type = 16; 1108 } else if (strstr(filename, ":12:")) { 1109 fat_type = 12; 1110 } 1111 1112 if (strstr(filename, ":floppy:")) { 1113 floppy = true; 1114 } 1115 1116 if (strstr(filename, ":rw:")) { 1117 rw = true; 1118 } 1119 1120 /* Get the directory name without options */ 1121 i = strrchr(filename, ':') - filename; 1122 assert(i >= 3); 1123 if (filename[i - 2] == ':' && qemu_isalpha(filename[i - 1])) { 1124 /* workaround for DOS drive names */ 1125 filename += i - 1; 1126 } else { 1127 filename += i + 1; 1128 } 1129 1130 /* Fill in the options QDict */ 1131 qdict_put_str(options, "dir", filename); 1132 qdict_put_int(options, "fat-type", fat_type); 1133 qdict_put_bool(options, "floppy", floppy); 1134 qdict_put_bool(options, "rw", rw); 1135 } 1136 1137 static int vvfat_open(BlockDriverState *bs, QDict *options, int flags, 1138 Error **errp) 1139 { 1140 BDRVVVFATState *s = bs->opaque; 1141 int cyls, heads, secs; 1142 bool floppy; 1143 const char *dirname, *label; 1144 QemuOpts *opts; 1145 int ret; 1146 1147 GRAPH_RDLOCK_GUARD_MAINLOOP(); 1148 1149 #ifdef DEBUG 1150 vvv = s; 1151 #endif 1152 1153 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 1154 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 1155 ret = -EINVAL; 1156 goto fail; 1157 } 1158 1159 dirname = qemu_opt_get(opts, "dir"); 1160 if (!dirname) { 1161 error_setg(errp, "vvfat block driver requires a 'dir' option"); 1162 ret = -EINVAL; 1163 goto fail; 1164 } 1165 1166 s->fat_type = qemu_opt_get_number(opts, "fat-type", 0); 1167 floppy = qemu_opt_get_bool(opts, "floppy", false); 1168 1169 memset(s->volume_label, ' ', sizeof(s->volume_label)); 1170 label = qemu_opt_get(opts, "label"); 1171 if (label) { 1172 size_t label_length = strlen(label); 1173 if (label_length > 11) { 1174 error_setg(errp, "vvfat label cannot be longer than 11 bytes"); 1175 ret = -EINVAL; 1176 goto fail; 1177 } 1178 memcpy(s->volume_label, label, label_length); 1179 } else { 1180 memcpy(s->volume_label, "QEMU VVFAT", 10); 1181 } 1182 1183 if (floppy) { 1184 /* 1.44MB or 2.88MB floppy. 2.88MB can be FAT12 (default) or FAT16. */ 1185 if (!s->fat_type) { 1186 s->fat_type = 12; 1187 secs = 36; 1188 s->sectors_per_cluster = 2; 1189 } else { 1190 secs = s->fat_type == 12 ? 18 : 36; 1191 s->sectors_per_cluster = 1; 1192 } 1193 cyls = 80; 1194 heads = 2; 1195 } else { 1196 /* 32MB or 504MB disk*/ 1197 if (!s->fat_type) { 1198 s->fat_type = 16; 1199 } 1200 s->offset_to_bootsector = 0x3f; 1201 cyls = s->fat_type == 12 ? 64 : 1024; 1202 heads = 16; 1203 secs = 63; 1204 } 1205 1206 switch (s->fat_type) { 1207 case 32: 1208 warn_report("FAT32 has not been tested. You are welcome to do so!"); 1209 break; 1210 case 16: 1211 case 12: 1212 break; 1213 default: 1214 error_setg(errp, "Valid FAT types are only 12, 16 and 32"); 1215 ret = -EINVAL; 1216 goto fail; 1217 } 1218 1219 1220 s->bs = bs; 1221 1222 /* LATER TODO: if FAT32, adjust */ 1223 s->sectors_per_cluster=0x10; 1224 1225 s->current_cluster=0xffffffff; 1226 1227 s->qcow = NULL; 1228 s->qcow_filename = NULL; 1229 s->fat2 = NULL; 1230 s->downcase_short_names = 1; 1231 1232 DLOG(fprintf(stderr, "vvfat %s chs %d,%d,%d\n", 1233 dirname, cyls, heads, secs)); 1234 1235 s->sector_count = cyls * heads * secs - s->offset_to_bootsector; 1236 bs->total_sectors = cyls * heads * secs; 1237 1238 if (qemu_opt_get_bool(opts, "rw", false)) { 1239 if (!bdrv_is_read_only(bs)) { 1240 ret = enable_write_target(bs, errp); 1241 if (ret < 0) { 1242 goto fail; 1243 } 1244 } else { 1245 ret = -EPERM; 1246 error_setg(errp, 1247 "Unable to set VVFAT to 'rw' when drive is read-only"); 1248 goto fail; 1249 } 1250 } else { 1251 ret = bdrv_apply_auto_read_only(bs, NULL, errp); 1252 if (ret < 0) { 1253 goto fail; 1254 } 1255 } 1256 1257 if (init_directories(s, dirname, heads, secs, errp)) { 1258 ret = -EIO; 1259 goto fail; 1260 } 1261 1262 s->sector_count = s->offset_to_root_dir 1263 + s->sectors_per_cluster * s->cluster_count; 1264 1265 /* Disable migration when vvfat is used rw */ 1266 if (s->qcow) { 1267 error_setg(&s->migration_blocker, 1268 "The vvfat (rw) format used by node '%s' " 1269 "does not support live migration", 1270 bdrv_get_device_or_node_name(bs)); 1271 ret = migrate_add_blocker_normal(&s->migration_blocker, errp); 1272 if (ret < 0) { 1273 goto fail; 1274 } 1275 } 1276 1277 if (s->offset_to_bootsector > 0) { 1278 init_mbr(s, cyls, heads, secs); 1279 } 1280 1281 qemu_co_mutex_init(&s->lock); 1282 1283 qemu_opts_del(opts); 1284 1285 return 0; 1286 1287 fail: 1288 g_free(s->qcow_filename); 1289 s->qcow_filename = NULL; 1290 g_free(s->cluster_buffer); 1291 s->cluster_buffer = NULL; 1292 g_free(s->used_clusters); 1293 s->used_clusters = NULL; 1294 1295 qemu_opts_del(opts); 1296 return ret; 1297 } 1298 1299 static void vvfat_refresh_limits(BlockDriverState *bs, Error **errp) 1300 { 1301 bs->bl.request_alignment = BDRV_SECTOR_SIZE; /* No sub-sector I/O */ 1302 } 1303 1304 static inline void vvfat_close_current_file(BDRVVVFATState *s) 1305 { 1306 if(s->current_mapping) { 1307 s->current_mapping = NULL; 1308 if (s->current_fd) { 1309 qemu_close(s->current_fd); 1310 s->current_fd = 0; 1311 } 1312 } 1313 s->current_cluster = -1; 1314 } 1315 1316 /* mappings between index1 and index2-1 are supposed to be ordered 1317 * return value is the index of the last mapping for which end>cluster_num 1318 */ 1319 static inline int find_mapping_for_cluster_aux(BDRVVVFATState* s,int cluster_num,int index1,int index2) 1320 { 1321 while(1) { 1322 int index3; 1323 mapping_t* mapping; 1324 index3=(index1+index2)/2; 1325 mapping=array_get(&(s->mapping),index3); 1326 assert(mapping->begin < mapping->end); 1327 if(mapping->begin>=cluster_num) { 1328 assert(index2!=index3 || index2==0); 1329 if(index2==index3) 1330 return index1; 1331 index2=index3; 1332 } else { 1333 if(index1==index3) 1334 return mapping->end<=cluster_num ? index2 : index1; 1335 index1=index3; 1336 } 1337 assert(index1<=index2); 1338 DLOG(mapping=array_get(&(s->mapping),index1); 1339 assert(mapping->begin<=cluster_num); 1340 assert(index2 >= s->mapping.next || 1341 ((mapping = array_get(&(s->mapping),index2)) && 1342 mapping->end>cluster_num))); 1343 } 1344 } 1345 1346 static inline mapping_t* find_mapping_for_cluster(BDRVVVFATState* s,int cluster_num) 1347 { 1348 int index=find_mapping_for_cluster_aux(s,cluster_num,0,s->mapping.next); 1349 mapping_t* mapping; 1350 if(index>=s->mapping.next) 1351 return NULL; 1352 mapping=array_get(&(s->mapping),index); 1353 if(mapping->begin>cluster_num) 1354 return NULL; 1355 assert(mapping->begin<=cluster_num && mapping->end>cluster_num); 1356 return mapping; 1357 } 1358 1359 static int open_file(BDRVVVFATState* s,mapping_t* mapping) 1360 { 1361 if(!mapping) 1362 return -1; 1363 if(!s->current_mapping || 1364 strcmp(s->current_mapping->path,mapping->path)) { 1365 /* open file */ 1366 int fd = qemu_open_old(mapping->path, 1367 O_RDONLY | O_BINARY | O_LARGEFILE); 1368 if(fd<0) 1369 return -1; 1370 vvfat_close_current_file(s); 1371 s->current_fd = fd; 1372 s->current_mapping = mapping; 1373 } 1374 return 0; 1375 } 1376 1377 static inline int read_cluster(BDRVVVFATState *s,int cluster_num) 1378 { 1379 if(s->current_cluster != cluster_num) { 1380 int result=0; 1381 off_t offset; 1382 assert(!s->current_mapping || s->current_fd || (s->current_mapping->mode & MODE_DIRECTORY)); 1383 if(!s->current_mapping 1384 || s->current_mapping->begin>cluster_num 1385 || s->current_mapping->end<=cluster_num) { 1386 /* binary search of mappings for file */ 1387 mapping_t* mapping=find_mapping_for_cluster(s,cluster_num); 1388 1389 assert(!mapping || (cluster_num>=mapping->begin && cluster_num<mapping->end)); 1390 1391 if (mapping && mapping->mode & MODE_DIRECTORY) { 1392 vvfat_close_current_file(s); 1393 s->current_mapping = mapping; 1394 read_cluster_directory: 1395 offset = s->cluster_size*(cluster_num-s->current_mapping->begin); 1396 s->cluster = (unsigned char*)s->directory.pointer+offset 1397 + 0x20*s->current_mapping->info.dir.first_dir_index; 1398 assert(((s->cluster-(unsigned char*)s->directory.pointer)%s->cluster_size)==0); 1399 assert((char*)s->cluster+s->cluster_size <= s->directory.pointer+s->directory.next*s->directory.item_size); 1400 s->current_cluster = cluster_num; 1401 return 0; 1402 } 1403 1404 if(open_file(s,mapping)) 1405 return -2; 1406 } else if (s->current_mapping->mode & MODE_DIRECTORY) 1407 goto read_cluster_directory; 1408 1409 assert(s->current_fd); 1410 1411 offset = s->cluster_size * 1412 ((cluster_num - s->current_mapping->begin) 1413 + s->current_mapping->info.file.offset); 1414 if(lseek(s->current_fd, offset, SEEK_SET)!=offset) 1415 return -3; 1416 s->cluster=s->cluster_buffer; 1417 result=read(s->current_fd,s->cluster,s->cluster_size); 1418 if(result<0) { 1419 s->current_cluster = -1; 1420 return -1; 1421 } 1422 s->current_cluster = cluster_num; 1423 } 1424 return 0; 1425 } 1426 1427 #ifdef DEBUG 1428 static void print_direntry(const direntry_t* direntry) 1429 { 1430 int j = 0; 1431 char buffer[1024]; 1432 1433 fprintf(stderr, "direntry %p: ", direntry); 1434 if(!direntry) 1435 return; 1436 if(is_long_name(direntry)) { 1437 unsigned char* c=(unsigned char*)direntry; 1438 int i; 1439 for(i=1;i<11 && c[i] && c[i]!=0xff;i+=2) 1440 #define ADD_CHAR(c) {buffer[j] = (c); if (buffer[j] < ' ') buffer[j] = 0xb0; j++;} 1441 ADD_CHAR(c[i]); 1442 for(i=14;i<26 && c[i] && c[i]!=0xff;i+=2) 1443 ADD_CHAR(c[i]); 1444 for(i=28;i<32 && c[i] && c[i]!=0xff;i+=2) 1445 ADD_CHAR(c[i]); 1446 buffer[j] = 0; 1447 fprintf(stderr, "%s\n", buffer); 1448 } else { 1449 int i; 1450 for(i=0;i<11;i++) 1451 ADD_CHAR(direntry->name[i]); 1452 buffer[j] = 0; 1453 fprintf(stderr, "%s attributes=0x%02x begin=%u size=%u\n", 1454 buffer, 1455 direntry->attributes, 1456 begin_of_direntry(direntry),le32_to_cpu(direntry->size)); 1457 } 1458 } 1459 1460 static void print_mapping(const mapping_t* mapping) 1461 { 1462 fprintf(stderr, "mapping (%p): begin, end = %u, %u, dir_index = %u, " 1463 "first_mapping_index = %d, name = %s, mode = 0x%x, " , 1464 mapping, mapping->begin, mapping->end, mapping->dir_index, 1465 mapping->first_mapping_index, mapping->path, mapping->mode); 1466 1467 if (mapping->mode & MODE_DIRECTORY) 1468 fprintf(stderr, "parent_mapping_index = %d, first_dir_index = %d\n", mapping->info.dir.parent_mapping_index, mapping->info.dir.first_dir_index); 1469 else 1470 fprintf(stderr, "offset = %u\n", mapping->info.file.offset); 1471 } 1472 #endif 1473 1474 static int coroutine_fn GRAPH_RDLOCK 1475 vvfat_read(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, int nb_sectors) 1476 { 1477 BDRVVVFATState *s = bs->opaque; 1478 int i; 1479 1480 for(i=0;i<nb_sectors;i++,sector_num++) { 1481 if (sector_num >= bs->total_sectors) 1482 return -1; 1483 if (s->qcow) { 1484 int64_t n; 1485 int ret; 1486 ret = bdrv_co_is_allocated(s->qcow->bs, sector_num * BDRV_SECTOR_SIZE, 1487 (nb_sectors - i) * BDRV_SECTOR_SIZE, &n); 1488 if (ret < 0) { 1489 return ret; 1490 } 1491 if (ret) { 1492 DLOG(fprintf(stderr, "sectors %" PRId64 "+%" PRId64 1493 " allocated\n", sector_num, 1494 n >> BDRV_SECTOR_BITS)); 1495 if (bdrv_co_pread(s->qcow, sector_num * BDRV_SECTOR_SIZE, n, 1496 buf + i * 0x200, 0) < 0) { 1497 return -1; 1498 } 1499 i += (n >> BDRV_SECTOR_BITS) - 1; 1500 sector_num += (n >> BDRV_SECTOR_BITS) - 1; 1501 continue; 1502 } 1503 DLOG(fprintf(stderr, "sector %" PRId64 " not allocated\n", 1504 sector_num)); 1505 } 1506 if (sector_num < s->offset_to_root_dir) { 1507 if (sector_num < s->offset_to_fat) { 1508 memcpy(buf + i * 0x200, 1509 &(s->first_sectors[sector_num * 0x200]), 1510 0x200); 1511 } else if (sector_num < s->offset_to_fat + s->sectors_per_fat) { 1512 memcpy(buf + i * 0x200, 1513 &(s->fat.pointer[(sector_num 1514 - s->offset_to_fat) * 0x200]), 1515 0x200); 1516 } else if (sector_num < s->offset_to_root_dir) { 1517 memcpy(buf + i * 0x200, 1518 &(s->fat.pointer[(sector_num - s->offset_to_fat 1519 - s->sectors_per_fat) * 0x200]), 1520 0x200); 1521 } 1522 } else { 1523 uint32_t sector = sector_num - s->offset_to_root_dir, 1524 sector_offset_in_cluster=(sector%s->sectors_per_cluster), 1525 cluster_num=sector/s->sectors_per_cluster; 1526 if(cluster_num > s->cluster_count || read_cluster(s, cluster_num) != 0) { 1527 /* LATER TODO: strict: return -1; */ 1528 memset(buf+i*0x200,0,0x200); 1529 continue; 1530 } 1531 memcpy(buf+i*0x200,s->cluster+sector_offset_in_cluster*0x200,0x200); 1532 } 1533 } 1534 return 0; 1535 } 1536 1537 static int coroutine_fn GRAPH_RDLOCK 1538 vvfat_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes, 1539 QEMUIOVector *qiov, BdrvRequestFlags flags) 1540 { 1541 int ret; 1542 BDRVVVFATState *s = bs->opaque; 1543 uint64_t sector_num = offset >> BDRV_SECTOR_BITS; 1544 int nb_sectors = bytes >> BDRV_SECTOR_BITS; 1545 void *buf; 1546 1547 assert(QEMU_IS_ALIGNED(offset, BDRV_SECTOR_SIZE)); 1548 assert(QEMU_IS_ALIGNED(bytes, BDRV_SECTOR_SIZE)); 1549 1550 buf = g_try_malloc(bytes); 1551 if (bytes && buf == NULL) { 1552 return -ENOMEM; 1553 } 1554 1555 qemu_co_mutex_lock(&s->lock); 1556 ret = vvfat_read(bs, sector_num, buf, nb_sectors); 1557 qemu_co_mutex_unlock(&s->lock); 1558 1559 qemu_iovec_from_buf(qiov, 0, buf, bytes); 1560 g_free(buf); 1561 1562 return ret; 1563 } 1564 1565 /* LATER TODO: statify all functions */ 1566 1567 /* 1568 * Idea of the write support (use snapshot): 1569 * 1570 * 1. check if all data is consistent, recording renames, modifications, 1571 * new files and directories (in s->commits). 1572 * 1573 * 2. if the data is not consistent, stop committing 1574 * 1575 * 3. handle renames, and create new files and directories (do not yet 1576 * write their contents) 1577 * 1578 * 4. walk the directories, fixing the mapping and direntries, and marking 1579 * the handled mappings as not deleted 1580 * 1581 * 5. commit the contents of the files 1582 * 1583 * 6. handle deleted files and directories 1584 * 1585 */ 1586 1587 typedef struct commit_t { 1588 char* path; 1589 union { 1590 struct { uint32_t cluster; } rename; 1591 struct { int dir_index; uint32_t modified_offset; } writeout; 1592 struct { uint32_t first_cluster; } new_file; 1593 struct { uint32_t cluster; } mkdir; 1594 } param; 1595 /* DELETEs and RMDIRs are handled differently: see handle_deletes() */ 1596 enum { 1597 ACTION_RENAME, ACTION_WRITEOUT, ACTION_NEW_FILE, ACTION_MKDIR 1598 } action; 1599 } commit_t; 1600 1601 static void clear_commits(BDRVVVFATState* s) 1602 { 1603 int i; 1604 DLOG(fprintf(stderr, "clear_commits (%u commits)\n", s->commits.next)); 1605 for (i = 0; i < s->commits.next; i++) { 1606 commit_t* commit = array_get(&(s->commits), i); 1607 assert(commit->path || commit->action == ACTION_WRITEOUT); 1608 if (commit->action != ACTION_WRITEOUT) { 1609 assert(commit->path); 1610 g_free(commit->path); 1611 } else 1612 assert(commit->path == NULL); 1613 } 1614 s->commits.next = 0; 1615 } 1616 1617 static void schedule_rename(BDRVVVFATState* s, 1618 uint32_t cluster, char* new_path) 1619 { 1620 commit_t* commit = array_get_next(&(s->commits)); 1621 commit->path = new_path; 1622 commit->param.rename.cluster = cluster; 1623 commit->action = ACTION_RENAME; 1624 } 1625 1626 static void schedule_writeout(BDRVVVFATState* s, 1627 int dir_index, uint32_t modified_offset) 1628 { 1629 commit_t* commit = array_get_next(&(s->commits)); 1630 commit->path = NULL; 1631 commit->param.writeout.dir_index = dir_index; 1632 commit->param.writeout.modified_offset = modified_offset; 1633 commit->action = ACTION_WRITEOUT; 1634 } 1635 1636 static void schedule_new_file(BDRVVVFATState* s, 1637 char* path, uint32_t first_cluster) 1638 { 1639 commit_t* commit = array_get_next(&(s->commits)); 1640 commit->path = path; 1641 commit->param.new_file.first_cluster = first_cluster; 1642 commit->action = ACTION_NEW_FILE; 1643 } 1644 1645 static void schedule_mkdir(BDRVVVFATState* s, uint32_t cluster, char* path) 1646 { 1647 commit_t* commit = array_get_next(&(s->commits)); 1648 commit->path = path; 1649 commit->param.mkdir.cluster = cluster; 1650 commit->action = ACTION_MKDIR; 1651 } 1652 1653 typedef struct { 1654 /* 1655 * Since the sequence number is at most 0x3f, and the filename 1656 * length is at most 13 times the sequence number, the maximal 1657 * filename length is 0x3f * 13 bytes. 1658 */ 1659 unsigned char name[0x3f * 13 + 1]; 1660 gunichar2 name2[0x3f * 13 + 1]; 1661 int checksum, len; 1662 int sequence_number; 1663 } long_file_name; 1664 1665 static void lfn_init(long_file_name* lfn) 1666 { 1667 lfn->sequence_number = lfn->len = 0; 1668 lfn->checksum = 0x100; 1669 } 1670 1671 /* return 0 if parsed successfully, > 0 if no long name, < 0 if error */ 1672 static int parse_long_name(long_file_name* lfn, 1673 const direntry_t* direntry) 1674 { 1675 int i, j, offset; 1676 const unsigned char* pointer = (const unsigned char*)direntry; 1677 1678 if (!is_long_name(direntry)) 1679 return 1; 1680 1681 if (pointer[0] & 0x40) { 1682 /* first entry; do some initialization */ 1683 lfn->sequence_number = pointer[0] & 0x3f; 1684 lfn->checksum = pointer[13]; 1685 lfn->name[0] = 0; 1686 lfn->name[lfn->sequence_number * 13] = 0; 1687 } else if ((pointer[0] & 0x3f) != --lfn->sequence_number) { 1688 /* not the expected sequence number */ 1689 return -1; 1690 } else if (pointer[13] != lfn->checksum) { 1691 /* not the expected checksum */ 1692 return -2; 1693 } else if (pointer[12] || pointer[26] || pointer[27]) { 1694 /* invalid zero fields */ 1695 return -3; 1696 } 1697 1698 offset = 13 * (lfn->sequence_number - 1); 1699 for (i = 0, j = 1; i < 13; i++, j+=2) { 1700 if (j == 11) 1701 j = 14; 1702 else if (j == 26) 1703 j = 28; 1704 1705 if (pointer[j] == 0 && pointer[j + 1] == 0) { 1706 /* end of long file name */ 1707 break; 1708 } 1709 gunichar2 c = (pointer[j + 1] << 8) + pointer[j]; 1710 lfn->name2[offset + i] = c; 1711 } 1712 1713 if (pointer[0] & 0x40) { 1714 /* first entry; set len */ 1715 lfn->len = offset + i; 1716 } 1717 if ((pointer[0] & 0x3f) == 0x01) { 1718 /* last entry; finalize entry */ 1719 glong olen; 1720 gchar *utf8 = g_utf16_to_utf8(lfn->name2, lfn->len, NULL, &olen, NULL); 1721 if (!utf8) { 1722 return -4; 1723 } 1724 lfn->len = olen; 1725 memcpy(lfn->name, utf8, olen + 1); 1726 g_free(utf8); 1727 } 1728 1729 return 0; 1730 } 1731 1732 /* returns 0 if successful, >0 if no short_name, and <0 on error */ 1733 static int parse_short_name(BDRVVVFATState* s, 1734 long_file_name* lfn, direntry_t* direntry) 1735 { 1736 int i, j; 1737 1738 if (!is_short_name(direntry)) 1739 return 1; 1740 1741 for (j = 7; j >= 0 && direntry->name[j] == ' '; j--); 1742 for (i = 0; i <= j; i++) { 1743 uint8_t c = direntry->name[i]; 1744 if (c != to_valid_short_char(c)) { 1745 return -1; 1746 } else if (s->downcase_short_names) { 1747 lfn->name[i] = qemu_tolower(direntry->name[i]); 1748 } else { 1749 lfn->name[i] = direntry->name[i]; 1750 } 1751 } 1752 1753 for (j = 2; j >= 0 && direntry->name[8 + j] == ' '; j--) { 1754 } 1755 if (j >= 0) { 1756 lfn->name[i++] = '.'; 1757 lfn->name[i + j + 1] = '\0'; 1758 for (;j >= 0; j--) { 1759 uint8_t c = direntry->name[8 + j]; 1760 if (c != to_valid_short_char(c)) { 1761 return -2; 1762 } else if (s->downcase_short_names) { 1763 lfn->name[i + j] = qemu_tolower(c); 1764 } else { 1765 lfn->name[i + j] = c; 1766 } 1767 } 1768 } else 1769 lfn->name[i + j + 1] = '\0'; 1770 1771 if (lfn->name[0] == DIR_KANJI_FAKE) { 1772 lfn->name[0] = DIR_KANJI; 1773 } 1774 lfn->len = strlen((char*)lfn->name); 1775 1776 return 0; 1777 } 1778 1779 static inline uint32_t modified_fat_get(BDRVVVFATState* s, 1780 unsigned int cluster) 1781 { 1782 if (cluster < s->last_cluster_of_root_directory) { 1783 if (cluster + 1 == s->last_cluster_of_root_directory) 1784 return s->max_fat_value; 1785 else 1786 return cluster + 1; 1787 } 1788 1789 if (s->fat_type==32) { 1790 uint32_t* entry=((uint32_t*)s->fat2)+cluster; 1791 return le32_to_cpu(*entry); 1792 } else if (s->fat_type==16) { 1793 uint16_t* entry=((uint16_t*)s->fat2)+cluster; 1794 return le16_to_cpu(*entry); 1795 } else { 1796 const uint8_t* x=s->fat2+cluster*3/2; 1797 return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff; 1798 } 1799 } 1800 1801 static inline bool coroutine_fn GRAPH_RDLOCK 1802 cluster_was_modified(BDRVVVFATState *s, uint32_t cluster_num) 1803 { 1804 int was_modified = 0; 1805 int i; 1806 1807 if (s->qcow == NULL) { 1808 return 0; 1809 } 1810 1811 for (i = 0; !was_modified && i < s->sectors_per_cluster; i++) { 1812 was_modified = bdrv_co_is_allocated(s->qcow->bs, 1813 (cluster2sector(s, cluster_num) + 1814 i) * BDRV_SECTOR_SIZE, 1815 BDRV_SECTOR_SIZE, NULL); 1816 } 1817 1818 /* 1819 * Note that this treats failures to learn allocation status the 1820 * same as if an allocation has occurred. It's as safe as 1821 * anything else, given that a failure to learn allocation status 1822 * will probably result in more failures. 1823 */ 1824 return !!was_modified; 1825 } 1826 1827 static const char* get_basename(const char* path) 1828 { 1829 char* basename = strrchr(path, '/'); 1830 if (basename == NULL) 1831 return path; 1832 else 1833 return basename + 1; /* strip '/' */ 1834 } 1835 1836 /* 1837 * The array s->used_clusters holds the states of the clusters. If it is 1838 * part of a file, it has bit 2 set, in case of a directory, bit 1. If it 1839 * was modified, bit 3 is set. 1840 * If any cluster is allocated, but not part of a file or directory, this 1841 * driver refuses to commit. 1842 */ 1843 typedef enum { 1844 USED_DIRECTORY = 1, USED_FILE = 2, USED_ANY = 3, USED_ALLOCATED = 4 1845 } used_t; 1846 1847 /* 1848 * get_cluster_count_for_direntry() not only determines how many clusters 1849 * are occupied by direntry, but also if it was renamed or modified. 1850 * 1851 * A file is thought to be renamed *only* if there already was a file with 1852 * exactly the same first cluster, but a different name. 1853 * 1854 * Further, the files/directories handled by this function are 1855 * assumed to be *not* deleted (and *only* those). 1856 */ 1857 static uint32_t coroutine_fn GRAPH_RDLOCK 1858 get_cluster_count_for_direntry(BDRVVVFATState* s, direntry_t* direntry, const char* path) 1859 { 1860 /* 1861 * This is a little bit tricky: 1862 * IF the guest OS just inserts a cluster into the file chain, 1863 * and leaves the rest alone, (i.e. the original file had clusters 1864 * 15 -> 16, but now has 15 -> 32 -> 16), then the following happens: 1865 * 1866 * - do_commit will write the cluster into the file at the given 1867 * offset, but 1868 * 1869 * - the cluster which is overwritten should be moved to a later 1870 * position in the file. 1871 * 1872 * I am not aware that any OS does something as braindead, but this 1873 * situation could happen anyway when not committing for a long time. 1874 * Just to be sure that this does not bite us, detect it, and copy the 1875 * contents of the clusters to-be-overwritten into the qcow. 1876 */ 1877 int copy_it = 0; 1878 int was_modified = 0; 1879 int32_t ret = 0; 1880 1881 uint32_t cluster_num = begin_of_direntry(direntry); 1882 uint32_t offset = 0; 1883 mapping_t* mapping = NULL; 1884 const char* basename2 = NULL; 1885 1886 vvfat_close_current_file(s); 1887 1888 /* the root directory */ 1889 if (cluster_num == 0) 1890 return 0; 1891 1892 /* write support */ 1893 if (s->qcow) { 1894 basename2 = get_basename(path); 1895 1896 mapping = find_mapping_for_cluster(s, cluster_num); 1897 1898 if (mapping) { 1899 const char* basename; 1900 1901 assert(mapping->mode & MODE_DELETED); 1902 mapping->mode &= ~MODE_DELETED; 1903 1904 basename = get_basename(mapping->path); 1905 1906 assert(mapping->mode & MODE_NORMAL); 1907 1908 /* rename */ 1909 if (strcmp(basename, basename2)) 1910 schedule_rename(s, cluster_num, g_strdup(path)); 1911 } else if (is_file(direntry)) 1912 /* new file */ 1913 schedule_new_file(s, g_strdup(path), cluster_num); 1914 else { 1915 abort(); 1916 return 0; 1917 } 1918 } 1919 1920 while(1) { 1921 if (s->qcow) { 1922 if (!copy_it && cluster_was_modified(s, cluster_num)) { 1923 if (mapping == NULL || 1924 mapping->begin > cluster_num || 1925 mapping->end <= cluster_num) 1926 mapping = find_mapping_for_cluster(s, cluster_num); 1927 1928 1929 if (mapping && 1930 (mapping->mode & MODE_DIRECTORY) == 0) { 1931 1932 /* was modified in qcow */ 1933 if (offset != s->cluster_size 1934 * ((cluster_num - mapping->begin) 1935 + mapping->info.file.offset)) { 1936 /* offset of this cluster in file chain has changed */ 1937 abort(); 1938 copy_it = 1; 1939 } else if (offset == 0) { 1940 const char* basename = get_basename(mapping->path); 1941 1942 if (strcmp(basename, basename2)) 1943 copy_it = 1; 1944 } 1945 assert(mapping->first_mapping_index == -1 1946 || mapping->info.file.offset > 0); 1947 1948 /* need to write out? */ 1949 if (!was_modified && is_file(direntry)) { 1950 was_modified = 1; 1951 schedule_writeout(s, mapping->dir_index, offset); 1952 } 1953 } 1954 } 1955 1956 if (copy_it) { 1957 int i; 1958 /* 1959 * This is horribly inefficient, but that is okay, since 1960 * it is rarely executed, if at all. 1961 */ 1962 int64_t offs = cluster2sector(s, cluster_num); 1963 1964 vvfat_close_current_file(s); 1965 for (i = 0; i < s->sectors_per_cluster; i++) { 1966 int res; 1967 1968 res = bdrv_co_is_allocated(s->qcow->bs, 1969 (offs + i) * BDRV_SECTOR_SIZE, 1970 BDRV_SECTOR_SIZE, NULL); 1971 if (res < 0) { 1972 return -1; 1973 } 1974 if (!res) { 1975 res = vvfat_read(s->bs, offs, s->cluster_buffer, 1); 1976 if (res) { 1977 return -1; 1978 } 1979 res = bdrv_co_pwrite(s->qcow, offs * BDRV_SECTOR_SIZE, 1980 BDRV_SECTOR_SIZE, s->cluster_buffer, 1981 0); 1982 if (res < 0) { 1983 return -2; 1984 } 1985 } 1986 } 1987 } 1988 } 1989 1990 ret++; 1991 if (s->used_clusters[cluster_num] & USED_ANY) 1992 return 0; 1993 s->used_clusters[cluster_num] = USED_FILE; 1994 1995 cluster_num = modified_fat_get(s, cluster_num); 1996 1997 if (fat_eof(s, cluster_num)) 1998 return ret; 1999 else if (cluster_num < 2 || cluster_num > s->max_fat_value - 16) 2000 return -1; 2001 2002 offset += s->cluster_size; 2003 } 2004 } 2005 2006 /* 2007 * This function looks at the modified data (qcow). 2008 * It returns 0 upon inconsistency or error, and the number of clusters 2009 * used by the directory, its subdirectories and their files. 2010 */ 2011 static int coroutine_fn GRAPH_RDLOCK 2012 check_directory_consistency(BDRVVVFATState *s, int cluster_num, const char* path) 2013 { 2014 int ret = 0; 2015 unsigned char* cluster = g_malloc(s->cluster_size); 2016 direntry_t* direntries = (direntry_t*)cluster; 2017 mapping_t* mapping = find_mapping_for_cluster(s, cluster_num); 2018 2019 long_file_name lfn; 2020 int path_len = strlen(path); 2021 char path2[PATH_MAX + 1]; 2022 2023 assert(path_len < PATH_MAX); /* len was tested before! */ 2024 pstrcpy(path2, sizeof(path2), path); 2025 path2[path_len] = '/'; 2026 path2[path_len + 1] = '\0'; 2027 2028 if (mapping) { 2029 const char* basename = get_basename(mapping->path); 2030 const char* basename2 = get_basename(path); 2031 2032 assert(mapping->mode & MODE_DIRECTORY); 2033 2034 assert(mapping->mode & MODE_DELETED); 2035 mapping->mode &= ~MODE_DELETED; 2036 2037 if (strcmp(basename, basename2)) 2038 schedule_rename(s, cluster_num, g_strdup(path)); 2039 } else 2040 /* new directory */ 2041 schedule_mkdir(s, cluster_num, g_strdup(path)); 2042 2043 lfn_init(&lfn); 2044 do { 2045 int i; 2046 int subret = 0; 2047 2048 ret++; 2049 2050 if (s->used_clusters[cluster_num] & USED_ANY) { 2051 fprintf(stderr, "cluster %d used more than once\n", (int)cluster_num); 2052 goto fail; 2053 } 2054 s->used_clusters[cluster_num] = USED_DIRECTORY; 2055 2056 DLOG(fprintf(stderr, "read cluster %d (sector %d)\n", (int)cluster_num, (int)cluster2sector(s, cluster_num))); 2057 subret = vvfat_read(s->bs, cluster2sector(s, cluster_num), cluster, 2058 s->sectors_per_cluster); 2059 if (subret) { 2060 fprintf(stderr, "Error fetching direntries\n"); 2061 fail: 2062 g_free(cluster); 2063 return 0; 2064 } 2065 2066 for (i = 0; i < 0x10 * s->sectors_per_cluster; i++) { 2067 int cluster_count = 0; 2068 2069 DLOG(fprintf(stderr, "check direntry %d:\n", i); print_direntry(direntries + i)); 2070 if (is_volume_label(direntries + i) || is_dot(direntries + i) || 2071 is_free(direntries + i)) 2072 continue; 2073 2074 subret = parse_long_name(&lfn, direntries + i); 2075 if (subret < 0) { 2076 fprintf(stderr, "Error in long name\n"); 2077 goto fail; 2078 } 2079 if (subret == 0 || is_free(direntries + i)) 2080 continue; 2081 2082 if (fat_chksum(direntries+i) != lfn.checksum) { 2083 subret = parse_short_name(s, &lfn, direntries + i); 2084 if (subret < 0) { 2085 fprintf(stderr, "Error in short name (%d)\n", subret); 2086 goto fail; 2087 } 2088 if (subret > 0 || !strcmp((char*)lfn.name, ".") 2089 || !strcmp((char*)lfn.name, "..")) 2090 continue; 2091 } 2092 lfn.checksum = 0x100; /* cannot use long name twice */ 2093 2094 if (!valid_filename(lfn.name)) { 2095 fprintf(stderr, "Invalid file name\n"); 2096 goto fail; 2097 } 2098 if (path_len + 1 + lfn.len >= PATH_MAX) { 2099 fprintf(stderr, "Name too long: %s/%s\n", path, lfn.name); 2100 goto fail; 2101 } 2102 pstrcpy(path2 + path_len + 1, sizeof(path2) - path_len - 1, 2103 (char*)lfn.name); 2104 2105 if (is_directory(direntries + i)) { 2106 if (begin_of_direntry(direntries + i) == 0) { 2107 DLOG(fprintf(stderr, "invalid begin for directory: %s\n", path2); print_direntry(direntries + i)); 2108 goto fail; 2109 } 2110 cluster_count = check_directory_consistency(s, 2111 begin_of_direntry(direntries + i), path2); 2112 if (cluster_count == 0) { 2113 DLOG(fprintf(stderr, "problem in directory %s:\n", path2); print_direntry(direntries + i)); 2114 goto fail; 2115 } 2116 } else if (is_file(direntries + i)) { 2117 /* check file size with FAT */ 2118 cluster_count = get_cluster_count_for_direntry(s, direntries + i, path2); 2119 if (cluster_count != 2120 DIV_ROUND_UP(le32_to_cpu(direntries[i].size), s->cluster_size)) { 2121 DLOG(fprintf(stderr, "Cluster count mismatch\n")); 2122 goto fail; 2123 } 2124 } else 2125 abort(); /* cluster_count = 0; */ 2126 2127 ret += cluster_count; 2128 } 2129 2130 cluster_num = modified_fat_get(s, cluster_num); 2131 } while(!fat_eof(s, cluster_num)); 2132 2133 g_free(cluster); 2134 return ret; 2135 } 2136 2137 /* returns 1 on success */ 2138 static int coroutine_fn GRAPH_RDLOCK 2139 is_consistent(BDRVVVFATState* s) 2140 { 2141 int i, check; 2142 int used_clusters_count = 0; 2143 2144 DLOG(checkpoint()); 2145 /* 2146 * - get modified FAT 2147 * - compare the two FATs (TODO) 2148 * - get buffer for marking used clusters 2149 * - recurse direntries from root (using bs->bdrv_pread to make 2150 * sure to get the new data) 2151 * - check that the FAT agrees with the size 2152 * - count the number of clusters occupied by this directory and 2153 * its files 2154 * - check that the cumulative used cluster count agrees with the 2155 * FAT 2156 * - if all is fine, return number of used clusters 2157 */ 2158 if (s->fat2 == NULL) { 2159 int size = 0x200 * s->sectors_per_fat; 2160 s->fat2 = g_malloc(size); 2161 memcpy(s->fat2, s->fat.pointer, size); 2162 } 2163 check = vvfat_read(s->bs, 2164 s->offset_to_fat, s->fat2, s->sectors_per_fat); 2165 if (check) { 2166 fprintf(stderr, "Could not copy fat\n"); 2167 return 0; 2168 } 2169 assert (s->used_clusters); 2170 for (i = 0; i < sector2cluster(s, s->sector_count); i++) 2171 s->used_clusters[i] &= ~USED_ANY; 2172 2173 clear_commits(s); 2174 2175 /* mark every mapped file/directory as deleted. 2176 * (check_directory_consistency() will unmark those still present). */ 2177 if (s->qcow) 2178 for (i = 0; i < s->mapping.next; i++) { 2179 mapping_t* mapping = array_get(&(s->mapping), i); 2180 if (mapping->first_mapping_index < 0) 2181 mapping->mode |= MODE_DELETED; 2182 } 2183 2184 used_clusters_count = check_directory_consistency(s, 0, s->path); 2185 if (used_clusters_count <= 0) { 2186 DLOG(fprintf(stderr, "problem in directory\n")); 2187 return 0; 2188 } 2189 2190 check = s->last_cluster_of_root_directory; 2191 for (i = check; i < sector2cluster(s, s->sector_count); i++) { 2192 if (modified_fat_get(s, i)) { 2193 if(!s->used_clusters[i]) { 2194 DLOG(fprintf(stderr, "FAT was modified (%d), but cluster is not used?\n", i)); 2195 return 0; 2196 } 2197 check++; 2198 } 2199 2200 if (s->used_clusters[i] == USED_ALLOCATED) { 2201 /* allocated, but not used... */ 2202 DLOG(fprintf(stderr, "unused, modified cluster: %d\n", i)); 2203 return 0; 2204 } 2205 } 2206 2207 if (check != used_clusters_count) 2208 return 0; 2209 2210 return used_clusters_count; 2211 } 2212 2213 static inline void adjust_mapping_indices(BDRVVVFATState* s, 2214 int offset, int adjust) 2215 { 2216 int i; 2217 2218 for (i = 0; i < s->mapping.next; i++) { 2219 mapping_t* mapping = array_get(&(s->mapping), i); 2220 2221 #define ADJUST_MAPPING_INDEX(name) \ 2222 if (mapping->name >= offset) \ 2223 mapping->name += adjust 2224 2225 ADJUST_MAPPING_INDEX(first_mapping_index); 2226 if (mapping->mode & MODE_DIRECTORY) 2227 ADJUST_MAPPING_INDEX(info.dir.parent_mapping_index); 2228 } 2229 } 2230 2231 /* insert or update mapping */ 2232 static mapping_t* insert_mapping(BDRVVVFATState* s, 2233 uint32_t begin, uint32_t end) 2234 { 2235 /* 2236 * - find mapping where mapping->begin >= begin, 2237 * - if mapping->begin > begin: insert 2238 * - adjust all references to mappings! 2239 * - else: adjust 2240 * - replace name 2241 */ 2242 int index = find_mapping_for_cluster_aux(s, begin, 0, s->mapping.next); 2243 mapping_t* mapping = NULL; 2244 mapping_t* first_mapping = array_get(&(s->mapping), 0); 2245 2246 if (index < s->mapping.next && (mapping = array_get(&(s->mapping), index)) 2247 && mapping->begin < begin) { 2248 mapping->end = begin; 2249 index++; 2250 mapping = array_get(&(s->mapping), index); 2251 } 2252 if (index >= s->mapping.next || mapping->begin > begin) { 2253 mapping = array_insert(&(s->mapping), index, 1); 2254 mapping->path = NULL; 2255 adjust_mapping_indices(s, index, +1); 2256 } 2257 2258 mapping->begin = begin; 2259 mapping->end = end; 2260 2261 DLOG(mapping_t* next_mapping; 2262 assert(index + 1 >= s->mapping.next || 2263 ((next_mapping = array_get(&(s->mapping), index + 1)) && 2264 next_mapping->begin >= end))); 2265 2266 if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer) 2267 s->current_mapping = array_get(&(s->mapping), 2268 s->current_mapping - first_mapping); 2269 2270 return mapping; 2271 } 2272 2273 static int remove_mapping(BDRVVVFATState* s, int mapping_index) 2274 { 2275 mapping_t* mapping = array_get(&(s->mapping), mapping_index); 2276 mapping_t* first_mapping = array_get(&(s->mapping), 0); 2277 2278 /* free mapping */ 2279 if (mapping->first_mapping_index < 0) { 2280 g_free(mapping->path); 2281 } 2282 2283 /* remove from s->mapping */ 2284 array_remove(&(s->mapping), mapping_index); 2285 2286 /* adjust all references to mappings */ 2287 adjust_mapping_indices(s, mapping_index, -1); 2288 2289 if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer) 2290 s->current_mapping = array_get(&(s->mapping), 2291 s->current_mapping - first_mapping); 2292 2293 return 0; 2294 } 2295 2296 static void adjust_dirindices(BDRVVVFATState* s, int offset, int adjust) 2297 { 2298 int i; 2299 for (i = 0; i < s->mapping.next; i++) { 2300 mapping_t* mapping = array_get(&(s->mapping), i); 2301 if (mapping->dir_index >= offset) 2302 mapping->dir_index += adjust; 2303 if ((mapping->mode & MODE_DIRECTORY) && 2304 mapping->info.dir.first_dir_index >= offset) 2305 mapping->info.dir.first_dir_index += adjust; 2306 } 2307 } 2308 2309 static direntry_t* insert_direntries(BDRVVVFATState* s, 2310 int dir_index, int count) 2311 { 2312 /* 2313 * make room in s->directory, 2314 * adjust_dirindices 2315 */ 2316 direntry_t* result = array_insert(&(s->directory), dir_index, count); 2317 if (result == NULL) 2318 return NULL; 2319 adjust_dirindices(s, dir_index, count); 2320 return result; 2321 } 2322 2323 static int remove_direntries(BDRVVVFATState* s, int dir_index, int count) 2324 { 2325 int ret = array_remove_slice(&(s->directory), dir_index, count); 2326 if (ret) 2327 return ret; 2328 adjust_dirindices(s, dir_index, -count); 2329 return 0; 2330 } 2331 2332 /* 2333 * Adapt the mappings of the cluster chain starting at first cluster 2334 * (i.e. if a file starts at first_cluster, the chain is followed according 2335 * to the modified fat, and the corresponding entries in s->mapping are 2336 * adjusted) 2337 */ 2338 static int commit_mappings(BDRVVVFATState* s, 2339 uint32_t first_cluster, int dir_index) 2340 { 2341 mapping_t* mapping = find_mapping_for_cluster(s, first_cluster); 2342 direntry_t* direntry = array_get(&(s->directory), dir_index); 2343 uint32_t cluster = first_cluster; 2344 2345 vvfat_close_current_file(s); 2346 2347 assert(mapping); 2348 assert(mapping->begin == first_cluster); 2349 mapping->first_mapping_index = -1; 2350 mapping->dir_index = dir_index; 2351 mapping->mode = (dir_index <= 0 || is_directory(direntry)) ? 2352 MODE_DIRECTORY : MODE_NORMAL; 2353 2354 while (!fat_eof(s, cluster)) { 2355 uint32_t c, c1; 2356 2357 for (c = cluster, c1 = modified_fat_get(s, c); c + 1 == c1; 2358 c = c1, c1 = modified_fat_get(s, c1)); 2359 2360 c++; 2361 if (c > mapping->end) { 2362 int index = array_index(&(s->mapping), mapping); 2363 int i, max_i = s->mapping.next - index; 2364 for (i = 1; i < max_i && mapping[i].begin < c; i++); 2365 while (--i > 0) 2366 remove_mapping(s, index + 1); 2367 } 2368 assert(mapping == array_get(&(s->mapping), s->mapping.next - 1) 2369 || mapping[1].begin >= c); 2370 mapping->end = c; 2371 2372 if (!fat_eof(s, c1)) { 2373 int i = find_mapping_for_cluster_aux(s, c1, 0, s->mapping.next); 2374 mapping_t* next_mapping = i >= s->mapping.next ? NULL : 2375 array_get(&(s->mapping), i); 2376 2377 if (next_mapping == NULL || next_mapping->begin > c1) { 2378 int i1 = array_index(&(s->mapping), mapping); 2379 2380 next_mapping = insert_mapping(s, c1, c1+1); 2381 2382 if (c1 < c) 2383 i1++; 2384 mapping = array_get(&(s->mapping), i1); 2385 } 2386 2387 next_mapping->dir_index = mapping->dir_index; 2388 next_mapping->first_mapping_index = 2389 mapping->first_mapping_index < 0 ? 2390 array_index(&(s->mapping), mapping) : 2391 mapping->first_mapping_index; 2392 next_mapping->path = mapping->path; 2393 next_mapping->mode = mapping->mode; 2394 next_mapping->read_only = mapping->read_only; 2395 if (mapping->mode & MODE_DIRECTORY) { 2396 next_mapping->info.dir.parent_mapping_index = 2397 mapping->info.dir.parent_mapping_index; 2398 next_mapping->info.dir.first_dir_index = 2399 mapping->info.dir.first_dir_index + 2400 0x10 * s->sectors_per_cluster * 2401 (mapping->end - mapping->begin); 2402 } else 2403 next_mapping->info.file.offset = mapping->info.file.offset + 2404 (mapping->end - mapping->begin); 2405 2406 mapping = next_mapping; 2407 } 2408 2409 cluster = c1; 2410 } 2411 2412 return 0; 2413 } 2414 2415 static int coroutine_fn GRAPH_RDLOCK 2416 commit_direntries(BDRVVVFATState* s, int dir_index, int parent_mapping_index) 2417 { 2418 direntry_t* direntry = array_get(&(s->directory), dir_index); 2419 uint32_t first_cluster = dir_index == 0 ? 0 : begin_of_direntry(direntry); 2420 mapping_t* mapping = find_mapping_for_cluster(s, first_cluster); 2421 int factor = 0x10 * s->sectors_per_cluster; 2422 int old_cluster_count, new_cluster_count; 2423 int current_dir_index; 2424 int first_dir_index; 2425 int ret, i; 2426 uint32_t c; 2427 2428 assert(direntry); 2429 assert(mapping); 2430 assert(mapping->begin == first_cluster); 2431 assert(mapping->info.dir.first_dir_index < s->directory.next); 2432 assert(mapping->mode & MODE_DIRECTORY); 2433 assert(dir_index == 0 || is_directory(direntry)); 2434 2435 DLOG(fprintf(stderr, "commit_direntries for %s, parent_mapping_index %d\n", 2436 mapping->path, parent_mapping_index)); 2437 2438 current_dir_index = mapping->info.dir.first_dir_index; 2439 first_dir_index = current_dir_index; 2440 mapping->info.dir.parent_mapping_index = parent_mapping_index; 2441 2442 if (first_cluster == 0) { 2443 old_cluster_count = new_cluster_count = 2444 s->last_cluster_of_root_directory; 2445 } else { 2446 for (old_cluster_count = 0, c = first_cluster; !fat_eof(s, c); 2447 c = fat_get(s, c)) 2448 old_cluster_count++; 2449 2450 for (new_cluster_count = 0, c = first_cluster; !fat_eof(s, c); 2451 c = modified_fat_get(s, c)) 2452 new_cluster_count++; 2453 } 2454 2455 if (new_cluster_count > old_cluster_count) { 2456 if (insert_direntries(s, 2457 current_dir_index + factor * old_cluster_count, 2458 factor * (new_cluster_count - old_cluster_count)) == NULL) 2459 return -1; 2460 } else if (new_cluster_count < old_cluster_count) 2461 remove_direntries(s, 2462 current_dir_index + factor * new_cluster_count, 2463 factor * (old_cluster_count - new_cluster_count)); 2464 2465 for (c = first_cluster; !fat_eof(s, c); c = modified_fat_get(s, c)) { 2466 direntry_t *first_direntry; 2467 2468 direntry = array_get(&(s->directory), current_dir_index); 2469 ret = vvfat_read(s->bs, cluster2sector(s, c), (uint8_t *)direntry, 2470 s->sectors_per_cluster); 2471 if (ret) 2472 return ret; 2473 2474 /* The first directory entry on the filesystem is the volume name */ 2475 first_direntry = (direntry_t*) s->directory.pointer; 2476 assert(!memcmp(first_direntry->name, s->volume_label, 11)); 2477 2478 current_dir_index += factor; 2479 } 2480 2481 ret = commit_mappings(s, first_cluster, dir_index); 2482 if (ret) 2483 return ret; 2484 2485 /* recurse */ 2486 for (i = 0; i < factor * new_cluster_count; i++) { 2487 direntry = array_get(&(s->directory), first_dir_index + i); 2488 if (is_directory(direntry) && !is_dot(direntry)) { 2489 mapping = find_mapping_for_cluster(s, first_cluster); 2490 if (mapping == NULL) { 2491 return -1; 2492 } 2493 assert(mapping->mode & MODE_DIRECTORY); 2494 ret = commit_direntries(s, first_dir_index + i, 2495 array_index(&(s->mapping), mapping)); 2496 if (ret) 2497 return ret; 2498 } 2499 } 2500 2501 return 0; 2502 } 2503 2504 /* commit one file (adjust contents, adjust mapping), 2505 return first_mapping_index */ 2506 static int coroutine_fn GRAPH_RDLOCK 2507 commit_one_file(BDRVVVFATState* s, int dir_index, uint32_t offset) 2508 { 2509 direntry_t* direntry = array_get(&(s->directory), dir_index); 2510 uint32_t c = begin_of_direntry(direntry); 2511 uint32_t first_cluster = c; 2512 mapping_t* mapping = find_mapping_for_cluster(s, c); 2513 uint32_t size = filesize_of_direntry(direntry); 2514 char *cluster; 2515 uint32_t i; 2516 int fd = 0; 2517 2518 assert(offset < size); 2519 assert((offset % s->cluster_size) == 0); 2520 2521 if (mapping == NULL) { 2522 return -1; 2523 } 2524 2525 for (i = 0; i < offset; i += s->cluster_size) { 2526 c = modified_fat_get(s, c); 2527 } 2528 2529 fd = qemu_open_old(mapping->path, O_RDWR | O_CREAT | O_BINARY, 0666); 2530 if (fd < 0) { 2531 fprintf(stderr, "Could not open %s... (%s, %d)\n", mapping->path, 2532 strerror(errno), errno); 2533 return fd; 2534 } 2535 if (offset > 0) { 2536 if (lseek(fd, offset, SEEK_SET) != offset) { 2537 qemu_close(fd); 2538 return -3; 2539 } 2540 } 2541 2542 cluster = g_malloc(s->cluster_size); 2543 2544 while (offset < size) { 2545 uint32_t c1; 2546 int rest_size = (size - offset > s->cluster_size ? 2547 s->cluster_size : size - offset); 2548 int ret; 2549 2550 c1 = modified_fat_get(s, c); 2551 2552 assert((size - offset == 0 && fat_eof(s, c)) || 2553 (size > offset && c >=2 && !fat_eof(s, c))); 2554 2555 ret = vvfat_read(s->bs, cluster2sector(s, c), 2556 (uint8_t*)cluster, DIV_ROUND_UP(rest_size, 0x200)); 2557 2558 if (ret < 0) { 2559 qemu_close(fd); 2560 g_free(cluster); 2561 return ret; 2562 } 2563 2564 if (write(fd, cluster, rest_size) < 0) { 2565 qemu_close(fd); 2566 g_free(cluster); 2567 return -2; 2568 } 2569 2570 offset += rest_size; 2571 c = c1; 2572 } 2573 2574 if (ftruncate(fd, size)) { 2575 perror("ftruncate()"); 2576 qemu_close(fd); 2577 g_free(cluster); 2578 return -4; 2579 } 2580 qemu_close(fd); 2581 g_free(cluster); 2582 2583 return commit_mappings(s, first_cluster, dir_index); 2584 } 2585 2586 #ifdef DEBUG 2587 /* test, if all mappings point to valid direntries */ 2588 static void check1(BDRVVVFATState* s) 2589 { 2590 int i; 2591 for (i = 0; i < s->mapping.next; i++) { 2592 mapping_t* mapping = array_get(&(s->mapping), i); 2593 if (mapping->mode & MODE_DELETED) { 2594 fprintf(stderr, "deleted\n"); 2595 continue; 2596 } 2597 assert(mapping->dir_index < s->directory.next); 2598 direntry_t* direntry = array_get(&(s->directory), mapping->dir_index); 2599 assert(mapping->begin == begin_of_direntry(direntry) || mapping->first_mapping_index >= 0); 2600 if (mapping->mode & MODE_DIRECTORY) { 2601 assert(mapping->info.dir.first_dir_index + 0x10 * s->sectors_per_cluster * (mapping->end - mapping->begin) <= s->directory.next); 2602 assert((mapping->info.dir.first_dir_index % (0x10 * s->sectors_per_cluster)) == 0); 2603 } 2604 } 2605 } 2606 2607 /* test, if all direntries have mappings */ 2608 static void check2(BDRVVVFATState* s) 2609 { 2610 int i; 2611 int first_mapping = -1; 2612 2613 for (i = 0; i < s->directory.next; i++) { 2614 direntry_t* direntry = array_get(&(s->directory), i); 2615 2616 if (is_short_name(direntry) && begin_of_direntry(direntry)) { 2617 mapping_t* mapping = find_mapping_for_cluster(s, begin_of_direntry(direntry)); 2618 assert(mapping); 2619 assert(mapping->dir_index == i || is_dot(direntry)); 2620 assert(mapping->begin == begin_of_direntry(direntry) || is_dot(direntry)); 2621 } 2622 2623 if ((i % (0x10 * s->sectors_per_cluster)) == 0) { 2624 /* cluster start */ 2625 int j, count = 0; 2626 2627 for (j = 0; j < s->mapping.next; j++) { 2628 mapping_t* mapping = array_get(&(s->mapping), j); 2629 if (mapping->mode & MODE_DELETED) 2630 continue; 2631 if (mapping->mode & MODE_DIRECTORY) { 2632 if (mapping->info.dir.first_dir_index <= i && mapping->info.dir.first_dir_index + 0x10 * s->sectors_per_cluster > i) { 2633 assert(++count == 1); 2634 if (mapping->first_mapping_index == -1) 2635 first_mapping = array_index(&(s->mapping), mapping); 2636 else 2637 assert(first_mapping == mapping->first_mapping_index); 2638 if (mapping->info.dir.parent_mapping_index < 0) 2639 assert(j == 0); 2640 else { 2641 mapping_t* parent = array_get(&(s->mapping), mapping->info.dir.parent_mapping_index); 2642 assert(parent->mode & MODE_DIRECTORY); 2643 assert(parent->info.dir.first_dir_index < mapping->info.dir.first_dir_index); 2644 } 2645 } 2646 } 2647 } 2648 if (count == 0) 2649 first_mapping = -1; 2650 } 2651 } 2652 } 2653 #endif 2654 2655 static int handle_renames_and_mkdirs(BDRVVVFATState* s) 2656 { 2657 int i; 2658 2659 #ifdef DEBUG 2660 fprintf(stderr, "handle_renames\n"); 2661 for (i = 0; i < s->commits.next; i++) { 2662 commit_t* commit = array_get(&(s->commits), i); 2663 fprintf(stderr, "%d, %s (%u, %d)\n", i, 2664 commit->path ? commit->path : "(null)", 2665 commit->param.rename.cluster, commit->action); 2666 } 2667 #endif 2668 2669 for (i = 0; i < s->commits.next;) { 2670 commit_t* commit = array_get(&(s->commits), i); 2671 if (commit->action == ACTION_RENAME) { 2672 mapping_t* mapping = find_mapping_for_cluster(s, 2673 commit->param.rename.cluster); 2674 char *old_path; 2675 2676 if (mapping == NULL) { 2677 return -1; 2678 } 2679 old_path = mapping->path; 2680 assert(commit->path); 2681 mapping->path = commit->path; 2682 if (rename(old_path, mapping->path)) 2683 return -2; 2684 2685 if (mapping->mode & MODE_DIRECTORY) { 2686 int l1 = strlen(mapping->path); 2687 int l2 = strlen(old_path); 2688 int diff = l1 - l2; 2689 direntry_t* direntry = array_get(&(s->directory), 2690 mapping->info.dir.first_dir_index); 2691 uint32_t c = mapping->begin; 2692 int j = 0; 2693 2694 /* recurse */ 2695 while (!fat_eof(s, c)) { 2696 do { 2697 direntry_t *d = direntry + j; 2698 2699 if (is_file(d) || (is_directory(d) && !is_dot(d))) { 2700 int l; 2701 char *new_path; 2702 mapping_t* m = find_mapping_for_cluster(s, 2703 begin_of_direntry(d)); 2704 if (m == NULL) { 2705 return -1; 2706 } 2707 l = strlen(m->path); 2708 new_path = g_malloc(l + diff + 1); 2709 2710 assert(!strncmp(m->path, mapping->path, l2)); 2711 2712 pstrcpy(new_path, l + diff + 1, mapping->path); 2713 pstrcpy(new_path + l1, l + diff + 1 - l1, 2714 m->path + l2); 2715 2716 schedule_rename(s, m->begin, new_path); 2717 } 2718 j++; 2719 } while (j % (0x10 * s->sectors_per_cluster) != 0); 2720 c = fat_get(s, c); 2721 } 2722 } 2723 2724 g_free(old_path); 2725 array_remove(&(s->commits), i); 2726 continue; 2727 } else if (commit->action == ACTION_MKDIR) { 2728 mapping_t* mapping; 2729 int j, parent_path_len; 2730 2731 if (g_mkdir(commit->path, 0755)) { 2732 return -5; 2733 } 2734 2735 mapping = insert_mapping(s, commit->param.mkdir.cluster, 2736 commit->param.mkdir.cluster + 1); 2737 if (mapping == NULL) 2738 return -6; 2739 2740 mapping->mode = MODE_DIRECTORY; 2741 mapping->read_only = 0; 2742 mapping->path = commit->path; 2743 j = s->directory.next; 2744 assert(j); 2745 insert_direntries(s, s->directory.next, 2746 0x10 * s->sectors_per_cluster); 2747 mapping->info.dir.first_dir_index = j; 2748 2749 parent_path_len = strlen(commit->path) 2750 - strlen(get_basename(commit->path)) - 1; 2751 for (j = 0; j < s->mapping.next; j++) { 2752 mapping_t* m = array_get(&(s->mapping), j); 2753 if (m->first_mapping_index < 0 && m != mapping && 2754 !strncmp(m->path, mapping->path, parent_path_len) && 2755 strlen(m->path) == parent_path_len) 2756 break; 2757 } 2758 assert(j < s->mapping.next); 2759 mapping->info.dir.parent_mapping_index = j; 2760 2761 array_remove(&(s->commits), i); 2762 continue; 2763 } 2764 2765 i++; 2766 } 2767 return 0; 2768 } 2769 2770 /* 2771 * TODO: make sure that the short name is not matching *another* file 2772 */ 2773 static int coroutine_fn GRAPH_RDLOCK handle_commits(BDRVVVFATState* s) 2774 { 2775 int i, fail = 0; 2776 2777 vvfat_close_current_file(s); 2778 2779 for (i = 0; !fail && i < s->commits.next; i++) { 2780 commit_t* commit = array_get(&(s->commits), i); 2781 switch(commit->action) { 2782 case ACTION_RENAME: case ACTION_MKDIR: 2783 abort(); 2784 fail = -2; 2785 break; 2786 case ACTION_WRITEOUT: { 2787 direntry_t* entry = array_get(&(s->directory), 2788 commit->param.writeout.dir_index); 2789 uint32_t begin = begin_of_direntry(entry); 2790 mapping_t* mapping = find_mapping_for_cluster(s, begin); 2791 2792 assert(mapping); 2793 assert(mapping->begin == begin); 2794 assert(commit->path == NULL); 2795 2796 if (commit_one_file(s, commit->param.writeout.dir_index, 2797 commit->param.writeout.modified_offset)) 2798 fail = -3; 2799 2800 break; 2801 } 2802 case ACTION_NEW_FILE: { 2803 int begin = commit->param.new_file.first_cluster; 2804 mapping_t* mapping = find_mapping_for_cluster(s, begin); 2805 direntry_t* entry; 2806 int j; 2807 2808 /* find direntry */ 2809 for (j = 0; j < s->directory.next; j++) { 2810 entry = array_get(&(s->directory), j); 2811 if (is_file(entry) && begin_of_direntry(entry) == begin) 2812 break; 2813 } 2814 2815 if (j >= s->directory.next) { 2816 fail = -6; 2817 continue; 2818 } 2819 2820 /* make sure there exists an initial mapping */ 2821 if (mapping && mapping->begin != begin) { 2822 mapping->end = begin; 2823 mapping = NULL; 2824 } 2825 if (mapping == NULL) { 2826 mapping = insert_mapping(s, begin, begin+1); 2827 } 2828 /* most members will be fixed in commit_mappings() */ 2829 assert(commit->path); 2830 mapping->path = commit->path; 2831 mapping->read_only = 0; 2832 mapping->mode = MODE_NORMAL; 2833 mapping->info.file.offset = 0; 2834 2835 if (commit_one_file(s, j, 0)) { 2836 fail = -7; 2837 } 2838 2839 break; 2840 } 2841 default: 2842 abort(); 2843 } 2844 } 2845 if (i > 0 && array_remove_slice(&(s->commits), 0, i)) 2846 return -1; 2847 return fail; 2848 } 2849 2850 static int handle_deletes(BDRVVVFATState* s) 2851 { 2852 int i, deferred = 1, deleted = 1; 2853 2854 /* delete files corresponding to mappings marked as deleted */ 2855 /* handle DELETEs and unused mappings (modified_fat_get(s, mapping->begin) == 0) */ 2856 while (deferred && deleted) { 2857 deferred = 0; 2858 deleted = 0; 2859 2860 for (i = 1; i < s->mapping.next; i++) { 2861 mapping_t* mapping = array_get(&(s->mapping), i); 2862 if (mapping->mode & MODE_DELETED) { 2863 direntry_t* entry = array_get(&(s->directory), 2864 mapping->dir_index); 2865 2866 if (is_free(entry)) { 2867 /* remove file/directory */ 2868 if (mapping->mode & MODE_DIRECTORY) { 2869 int j, next_dir_index = s->directory.next, 2870 first_dir_index = mapping->info.dir.first_dir_index; 2871 2872 if (rmdir(mapping->path) < 0) { 2873 if (errno == ENOTEMPTY) { 2874 deferred++; 2875 continue; 2876 } else 2877 return -5; 2878 } 2879 2880 for (j = 1; j < s->mapping.next; j++) { 2881 mapping_t* m = array_get(&(s->mapping), j); 2882 if (m->mode & MODE_DIRECTORY && 2883 m->info.dir.first_dir_index > 2884 first_dir_index && 2885 m->info.dir.first_dir_index < 2886 next_dir_index) 2887 next_dir_index = 2888 m->info.dir.first_dir_index; 2889 } 2890 remove_direntries(s, first_dir_index, 2891 next_dir_index - first_dir_index); 2892 2893 deleted++; 2894 } 2895 } else { 2896 if (unlink(mapping->path)) 2897 return -4; 2898 deleted++; 2899 } 2900 DLOG(fprintf(stderr, "DELETE (%d)\n", i); print_mapping(mapping); print_direntry(entry)); 2901 remove_mapping(s, i); 2902 } 2903 } 2904 } 2905 2906 return 0; 2907 } 2908 2909 /* 2910 * synchronize mapping with new state: 2911 * 2912 * - copy FAT (with bdrv_pread) 2913 * - mark all filenames corresponding to mappings as deleted 2914 * - recurse direntries from root (using bs->bdrv_pread) 2915 * - delete files corresponding to mappings marked as deleted 2916 */ 2917 static int coroutine_fn GRAPH_RDLOCK do_commit(BDRVVVFATState* s) 2918 { 2919 int ret = 0; 2920 2921 /* the real meat are the commits. Nothing to do? Move along! */ 2922 if (s->commits.next == 0) 2923 return 0; 2924 2925 vvfat_close_current_file(s); 2926 2927 ret = handle_renames_and_mkdirs(s); 2928 if (ret) { 2929 fprintf(stderr, "Error handling renames (%d)\n", ret); 2930 abort(); 2931 return ret; 2932 } 2933 2934 /* copy FAT (with bdrv_pread) */ 2935 memcpy(s->fat.pointer, s->fat2, 0x200 * s->sectors_per_fat); 2936 2937 /* recurse direntries from root (using bs->bdrv_pread) */ 2938 ret = commit_direntries(s, 0, -1); 2939 if (ret) { 2940 fprintf(stderr, "Fatal: error while committing (%d)\n", ret); 2941 abort(); 2942 return ret; 2943 } 2944 2945 ret = handle_commits(s); 2946 if (ret) { 2947 fprintf(stderr, "Error handling commits (%d)\n", ret); 2948 abort(); 2949 return ret; 2950 } 2951 2952 ret = handle_deletes(s); 2953 if (ret) { 2954 fprintf(stderr, "Error deleting\n"); 2955 abort(); 2956 return ret; 2957 } 2958 2959 bdrv_make_empty(s->qcow, NULL); 2960 2961 memset(s->used_clusters, 0, sector2cluster(s, s->sector_count)); 2962 2963 DLOG(checkpoint()); 2964 return 0; 2965 } 2966 2967 static int coroutine_fn GRAPH_RDLOCK try_commit(BDRVVVFATState* s) 2968 { 2969 vvfat_close_current_file(s); 2970 DLOG(checkpoint()); 2971 if(!is_consistent(s)) 2972 return -1; 2973 return do_commit(s); 2974 } 2975 2976 static int coroutine_fn GRAPH_RDLOCK 2977 vvfat_write(BlockDriverState *bs, int64_t sector_num, 2978 const uint8_t *buf, int nb_sectors) 2979 { 2980 BDRVVVFATState *s = bs->opaque; 2981 int i, ret; 2982 int first_cluster, last_cluster; 2983 2984 DLOG(checkpoint()); 2985 2986 /* Check if we're operating in read-only mode */ 2987 if (s->qcow == NULL) { 2988 return -EACCES; 2989 } 2990 2991 vvfat_close_current_file(s); 2992 2993 if (sector_num == s->offset_to_bootsector && nb_sectors == 1) { 2994 /* 2995 * Write on bootsector. Allow only changing the reserved1 field, 2996 * used to mark volume dirtiness 2997 */ 2998 unsigned char *bootsector = s->first_sectors 2999 + s->offset_to_bootsector * 0x200; 3000 /* 3001 * LATER TODO: if FAT32, this is wrong (see init_directories(), 3002 * which always creates a FAT16 bootsector) 3003 */ 3004 const int reserved1_offset = offsetof(bootsector_t, u.fat16.reserved1); 3005 3006 for (i = 0; i < 0x200; i++) { 3007 if (i != reserved1_offset && bootsector[i] != buf[i]) { 3008 fprintf(stderr, "Tried to write to protected bootsector\n"); 3009 return -1; 3010 } 3011 } 3012 3013 /* Update bootsector with the only updatable byte, and return success */ 3014 bootsector[reserved1_offset] = buf[reserved1_offset]; 3015 return 0; 3016 } 3017 3018 /* 3019 * Some sanity checks: 3020 * - do not allow writing to the boot sector 3021 */ 3022 if (sector_num < s->offset_to_fat) 3023 return -1; 3024 3025 /* 3026 * Values will be negative for writes to the FAT, which is located before 3027 * the root directory. 3028 */ 3029 first_cluster = sector2cluster(s, sector_num); 3030 last_cluster = sector2cluster(s, sector_num + nb_sectors - 1); 3031 3032 for (i = first_cluster; i <= last_cluster;) { 3033 mapping_t *mapping = NULL; 3034 3035 if (i >= 0) { 3036 mapping = find_mapping_for_cluster(s, i); 3037 } 3038 3039 if (mapping) { 3040 if (mapping->read_only) { 3041 fprintf(stderr, "Tried to write to write-protected file %s\n", 3042 mapping->path); 3043 return -1; 3044 } 3045 3046 if (mapping->mode & MODE_DIRECTORY) { 3047 int begin = cluster2sector(s, i); 3048 int end = begin + s->sectors_per_cluster, k; 3049 int dir_index; 3050 const direntry_t* direntries; 3051 long_file_name lfn; 3052 3053 lfn_init(&lfn); 3054 3055 if (begin < sector_num) 3056 begin = sector_num; 3057 if (end > sector_num + nb_sectors) 3058 end = sector_num + nb_sectors; 3059 dir_index = mapping->dir_index + 3060 0x10 * (begin - mapping->begin * s->sectors_per_cluster); 3061 direntries = (direntry_t*)(buf + 0x200 * (begin - sector_num)); 3062 3063 for (k = 0; k < (end - begin) * 0x10; k++) { 3064 /* no access to the direntry of a read-only file */ 3065 if (is_short_name(direntries + k) && 3066 (direntries[k].attributes & 1)) { 3067 if (memcmp(direntries + k, 3068 array_get(&(s->directory), dir_index + k), 3069 sizeof(direntry_t))) { 3070 warn_report("tried to write to write-protected " 3071 "file"); 3072 return -1; 3073 } 3074 } 3075 } 3076 } 3077 i = mapping->end; 3078 } else { 3079 i++; 3080 } 3081 } 3082 3083 /* 3084 * Use qcow backend. Commit later. 3085 */ 3086 DLOG(fprintf(stderr, "Write to qcow backend: %d + %d\n", (int)sector_num, nb_sectors)); 3087 ret = bdrv_co_pwrite(s->qcow, sector_num * BDRV_SECTOR_SIZE, 3088 nb_sectors * BDRV_SECTOR_SIZE, buf, 0); 3089 if (ret < 0) { 3090 fprintf(stderr, "Error writing to qcow backend\n"); 3091 return ret; 3092 } 3093 3094 for (i = first_cluster; i <= last_cluster; i++) { 3095 if (i >= 0) { 3096 s->used_clusters[i] |= USED_ALLOCATED; 3097 } 3098 } 3099 3100 DLOG(checkpoint()); 3101 /* TODO: add timeout */ 3102 try_commit(s); 3103 3104 DLOG(checkpoint()); 3105 return 0; 3106 } 3107 3108 static int coroutine_fn GRAPH_RDLOCK 3109 vvfat_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes, 3110 QEMUIOVector *qiov, BdrvRequestFlags flags) 3111 { 3112 int ret; 3113 BDRVVVFATState *s = bs->opaque; 3114 uint64_t sector_num = offset >> BDRV_SECTOR_BITS; 3115 int nb_sectors = bytes >> BDRV_SECTOR_BITS; 3116 void *buf; 3117 3118 assert(QEMU_IS_ALIGNED(offset, BDRV_SECTOR_SIZE)); 3119 assert(QEMU_IS_ALIGNED(bytes, BDRV_SECTOR_SIZE)); 3120 3121 buf = g_try_malloc(bytes); 3122 if (bytes && buf == NULL) { 3123 return -ENOMEM; 3124 } 3125 qemu_iovec_to_buf(qiov, 0, buf, bytes); 3126 3127 qemu_co_mutex_lock(&s->lock); 3128 ret = vvfat_write(bs, sector_num, buf, nb_sectors); 3129 qemu_co_mutex_unlock(&s->lock); 3130 3131 g_free(buf); 3132 3133 return ret; 3134 } 3135 3136 static int coroutine_fn vvfat_co_block_status(BlockDriverState *bs, 3137 bool want_zero, int64_t offset, 3138 int64_t bytes, int64_t *n, 3139 int64_t *map, 3140 BlockDriverState **file) 3141 { 3142 *n = bytes; 3143 return BDRV_BLOCK_DATA; 3144 } 3145 3146 static void vvfat_qcow_options(BdrvChildRole role, bool parent_is_format, 3147 int *child_flags, QDict *child_options, 3148 int parent_flags, QDict *parent_options) 3149 { 3150 qdict_set_default_str(child_options, BDRV_OPT_READ_ONLY, "off"); 3151 qdict_set_default_str(child_options, BDRV_OPT_AUTO_READ_ONLY, "off"); 3152 qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on"); 3153 } 3154 3155 static BdrvChildClass child_vvfat_qcow; 3156 3157 static int enable_write_target(BlockDriverState *bs, Error **errp) 3158 { 3159 BDRVVVFATState *s = bs->opaque; 3160 BlockDriver *bdrv_qcow = NULL; 3161 QemuOpts *opts = NULL; 3162 int ret; 3163 int size = sector2cluster(s, s->sector_count); 3164 QDict *options; 3165 3166 s->used_clusters = g_malloc0(size); 3167 3168 array_init(&(s->commits), sizeof(commit_t)); 3169 3170 s->qcow_filename = create_tmp_file(errp); 3171 if (!s->qcow_filename) { 3172 ret = -ENOENT; 3173 goto err; 3174 } 3175 3176 bdrv_qcow = bdrv_find_format("qcow"); 3177 if (!bdrv_qcow) { 3178 error_setg(errp, "Failed to locate qcow driver"); 3179 ret = -ENOENT; 3180 goto err; 3181 } 3182 3183 opts = qemu_opts_create(bdrv_qcow->create_opts, NULL, 0, &error_abort); 3184 qemu_opt_set_number(opts, BLOCK_OPT_SIZE, 3185 bs->total_sectors * BDRV_SECTOR_SIZE, &error_abort); 3186 qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, "fat:", &error_abort); 3187 3188 ret = bdrv_create(bdrv_qcow, s->qcow_filename, opts, errp); 3189 qemu_opts_del(opts); 3190 if (ret < 0) { 3191 goto err; 3192 } 3193 3194 options = qdict_new(); 3195 qdict_put_str(options, "write-target.driver", "qcow"); 3196 s->qcow = bdrv_open_child(s->qcow_filename, options, "write-target", bs, 3197 &child_vvfat_qcow, 3198 BDRV_CHILD_DATA | BDRV_CHILD_METADATA, 3199 false, errp); 3200 qobject_unref(options); 3201 if (!s->qcow) { 3202 ret = -EINVAL; 3203 goto err; 3204 } 3205 3206 #ifndef _WIN32 3207 unlink(s->qcow_filename); 3208 #endif 3209 3210 return 0; 3211 3212 err: 3213 return ret; 3214 } 3215 3216 static void vvfat_child_perm(BlockDriverState *bs, BdrvChild *c, 3217 BdrvChildRole role, 3218 BlockReopenQueue *reopen_queue, 3219 uint64_t perm, uint64_t shared, 3220 uint64_t *nperm, uint64_t *nshared) 3221 { 3222 assert(role & BDRV_CHILD_DATA); 3223 /* This is a private node, nobody should try to attach to it */ 3224 *nperm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE; 3225 *nshared = BLK_PERM_WRITE_UNCHANGED; 3226 } 3227 3228 static void vvfat_close(BlockDriverState *bs) 3229 { 3230 BDRVVVFATState *s = bs->opaque; 3231 3232 vvfat_close_current_file(s); 3233 array_free(&(s->fat)); 3234 array_free(&(s->directory)); 3235 array_free(&(s->mapping)); 3236 g_free(s->cluster_buffer); 3237 3238 if (s->qcow) { 3239 migrate_del_blocker(&s->migration_blocker); 3240 } 3241 } 3242 3243 static const char *const vvfat_strong_runtime_opts[] = { 3244 "dir", 3245 "fat-type", 3246 "floppy", 3247 "label", 3248 "rw", 3249 3250 NULL 3251 }; 3252 3253 static BlockDriver bdrv_vvfat = { 3254 .format_name = "vvfat", 3255 .protocol_name = "fat", 3256 .instance_size = sizeof(BDRVVVFATState), 3257 3258 .bdrv_parse_filename = vvfat_parse_filename, 3259 .bdrv_open = vvfat_open, 3260 .bdrv_refresh_limits = vvfat_refresh_limits, 3261 .bdrv_close = vvfat_close, 3262 .bdrv_child_perm = vvfat_child_perm, 3263 3264 .bdrv_co_preadv = vvfat_co_preadv, 3265 .bdrv_co_pwritev = vvfat_co_pwritev, 3266 .bdrv_co_block_status = vvfat_co_block_status, 3267 3268 .strong_runtime_opts = vvfat_strong_runtime_opts, 3269 }; 3270 3271 static void bdrv_vvfat_init(void) 3272 { 3273 child_vvfat_qcow = child_of_bds; 3274 child_vvfat_qcow.inherit_options = vvfat_qcow_options; 3275 bdrv_register(&bdrv_vvfat); 3276 } 3277 3278 block_init(bdrv_vvfat_init); 3279 3280 #ifdef DEBUG 3281 static void checkpoint(void) 3282 { 3283 assert(((mapping_t*)array_get(&(vvv->mapping), 0))->end == 2); 3284 check1(vvv); 3285 check2(vvv); 3286 assert(!vvv->current_mapping || vvv->current_fd || (vvv->current_mapping->mode & MODE_DIRECTORY)); 3287 } 3288 #endif 3289