1 /* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright (C) 2001-2003 Red Hat, Inc. 5 * 6 * Created by David Woodhouse <dwmw2@infradead.org> 7 * 8 * For licensing information, see the file 'LICENCE' in this directory. 9 * 10 * $Id: scan.c,v 1.125 2005/09/30 13:59:13 dedekind Exp $ 11 * 12 */ 13 #include <linux/kernel.h> 14 #include <linux/sched.h> 15 #include <linux/slab.h> 16 #include <linux/mtd/mtd.h> 17 #include <linux/pagemap.h> 18 #include <linux/crc32.h> 19 #include <linux/compiler.h> 20 #include "nodelist.h" 21 #include "summary.h" 22 #include "debug.h" 23 24 #define DEFAULT_EMPTY_SCAN_SIZE 1024 25 26 #define noisy_printk(noise, args...) do { \ 27 if (*(noise)) { \ 28 printk(KERN_NOTICE args); \ 29 (*(noise))--; \ 30 if (!(*(noise))) { \ 31 printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \ 32 } \ 33 } \ 34 } while(0) 35 36 static uint32_t pseudo_random; 37 38 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 39 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s); 40 41 /* These helper functions _must_ increase ofs and also do the dirty/used space accounting. 42 * Returning an error will abort the mount - bad checksums etc. should just mark the space 43 * as dirty. 44 */ 45 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 46 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s); 47 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 48 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s); 49 50 static inline int min_free(struct jffs2_sb_info *c) 51 { 52 uint32_t min = 2 * sizeof(struct jffs2_raw_inode); 53 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 54 if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize) 55 return c->wbuf_pagesize; 56 #endif 57 return min; 58 59 } 60 61 static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size) { 62 if (sector_size < DEFAULT_EMPTY_SCAN_SIZE) 63 return sector_size; 64 else 65 return DEFAULT_EMPTY_SCAN_SIZE; 66 } 67 68 int jffs2_scan_medium(struct jffs2_sb_info *c) 69 { 70 int i, ret; 71 uint32_t empty_blocks = 0, bad_blocks = 0; 72 unsigned char *flashbuf = NULL; 73 uint32_t buf_size = 0; 74 struct jffs2_summary *s = NULL; /* summary info collected by the scan process */ 75 #ifndef __ECOS 76 size_t pointlen; 77 78 if (c->mtd->point) { 79 ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf); 80 if (!ret && pointlen < c->mtd->size) { 81 /* Don't muck about if it won't let us point to the whole flash */ 82 D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen)); 83 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 84 flashbuf = NULL; 85 } 86 if (ret) 87 D1(printk(KERN_DEBUG "MTD point failed %d\n", ret)); 88 } 89 #endif 90 if (!flashbuf) { 91 /* For NAND it's quicker to read a whole eraseblock at a time, 92 apparently */ 93 if (jffs2_cleanmarker_oob(c)) 94 buf_size = c->sector_size; 95 else 96 buf_size = PAGE_SIZE; 97 98 /* Respect kmalloc limitations */ 99 if (buf_size > 128*1024) 100 buf_size = 128*1024; 101 102 D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size)); 103 flashbuf = kmalloc(buf_size, GFP_KERNEL); 104 if (!flashbuf) 105 return -ENOMEM; 106 } 107 108 if (jffs2_sum_active()) { 109 s = kmalloc(sizeof(struct jffs2_summary), GFP_KERNEL); 110 if (!s) { 111 JFFS2_WARNING("Can't allocate memory for summary\n"); 112 return -ENOMEM; 113 } 114 memset(s, 0, sizeof(struct jffs2_summary)); 115 } 116 117 for (i=0; i<c->nr_blocks; i++) { 118 struct jffs2_eraseblock *jeb = &c->blocks[i]; 119 120 /* reset summary info for next eraseblock scan */ 121 jffs2_sum_reset_collected(s); 122 123 ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset), 124 buf_size, s); 125 126 if (ret < 0) 127 goto out; 128 129 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 130 131 /* Now decide which list to put it on */ 132 switch(ret) { 133 case BLK_STATE_ALLFF: 134 /* 135 * Empty block. Since we can't be sure it 136 * was entirely erased, we just queue it for erase 137 * again. It will be marked as such when the erase 138 * is complete. Meanwhile we still count it as empty 139 * for later checks. 140 */ 141 empty_blocks++; 142 list_add(&jeb->list, &c->erase_pending_list); 143 c->nr_erasing_blocks++; 144 break; 145 146 case BLK_STATE_CLEANMARKER: 147 /* Only a CLEANMARKER node is valid */ 148 if (!jeb->dirty_size) { 149 /* It's actually free */ 150 list_add(&jeb->list, &c->free_list); 151 c->nr_free_blocks++; 152 } else { 153 /* Dirt */ 154 D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset)); 155 list_add(&jeb->list, &c->erase_pending_list); 156 c->nr_erasing_blocks++; 157 } 158 break; 159 160 case BLK_STATE_CLEAN: 161 /* Full (or almost full) of clean data. Clean list */ 162 list_add(&jeb->list, &c->clean_list); 163 break; 164 165 case BLK_STATE_PARTDIRTY: 166 /* Some data, but not full. Dirty list. */ 167 /* We want to remember the block with most free space 168 and stick it in the 'nextblock' position to start writing to it. */ 169 if (jeb->free_size > min_free(c) && 170 (!c->nextblock || c->nextblock->free_size < jeb->free_size)) { 171 /* Better candidate for the next writes to go to */ 172 if (c->nextblock) { 173 c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; 174 c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; 175 c->free_size -= c->nextblock->free_size; 176 c->wasted_size -= c->nextblock->wasted_size; 177 c->nextblock->free_size = c->nextblock->wasted_size = 0; 178 if (VERYDIRTY(c, c->nextblock->dirty_size)) { 179 list_add(&c->nextblock->list, &c->very_dirty_list); 180 } else { 181 list_add(&c->nextblock->list, &c->dirty_list); 182 } 183 /* deleting summary information of the old nextblock */ 184 jffs2_sum_reset_collected(c->summary); 185 } 186 /* update collected summary infromation for the current nextblock */ 187 jffs2_sum_move_collected(c, s); 188 D1(printk(KERN_DEBUG "jffs2_scan_medium(): new nextblock = 0x%08x\n", jeb->offset)); 189 c->nextblock = jeb; 190 } else { 191 jeb->dirty_size += jeb->free_size + jeb->wasted_size; 192 c->dirty_size += jeb->free_size + jeb->wasted_size; 193 c->free_size -= jeb->free_size; 194 c->wasted_size -= jeb->wasted_size; 195 jeb->free_size = jeb->wasted_size = 0; 196 if (VERYDIRTY(c, jeb->dirty_size)) { 197 list_add(&jeb->list, &c->very_dirty_list); 198 } else { 199 list_add(&jeb->list, &c->dirty_list); 200 } 201 } 202 break; 203 204 case BLK_STATE_ALLDIRTY: 205 /* Nothing valid - not even a clean marker. Needs erasing. */ 206 /* For now we just put it on the erasing list. We'll start the erases later */ 207 D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset)); 208 list_add(&jeb->list, &c->erase_pending_list); 209 c->nr_erasing_blocks++; 210 break; 211 212 case BLK_STATE_BADBLOCK: 213 D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset)); 214 list_add(&jeb->list, &c->bad_list); 215 c->bad_size += c->sector_size; 216 c->free_size -= c->sector_size; 217 bad_blocks++; 218 break; 219 default: 220 printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n"); 221 BUG(); 222 } 223 } 224 225 if (jffs2_sum_active() && s) 226 kfree(s); 227 228 /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */ 229 if (c->nextblock && (c->nextblock->dirty_size)) { 230 c->nextblock->wasted_size += c->nextblock->dirty_size; 231 c->wasted_size += c->nextblock->dirty_size; 232 c->dirty_size -= c->nextblock->dirty_size; 233 c->nextblock->dirty_size = 0; 234 } 235 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 236 if (!jffs2_can_mark_obsolete(c) && c->nextblock && (c->nextblock->free_size % c->wbuf_pagesize)) { 237 /* If we're going to start writing into a block which already 238 contains data, and the end of the data isn't page-aligned, 239 skip a little and align it. */ 240 241 uint32_t skip = c->nextblock->free_size % c->wbuf_pagesize; 242 243 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n", 244 skip)); 245 c->nextblock->wasted_size += skip; 246 c->wasted_size += skip; 247 248 c->nextblock->free_size -= skip; 249 c->free_size -= skip; 250 } 251 #endif 252 if (c->nr_erasing_blocks) { 253 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) { 254 printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n"); 255 printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks); 256 ret = -EIO; 257 goto out; 258 } 259 jffs2_erase_pending_trigger(c); 260 } 261 ret = 0; 262 out: 263 if (buf_size) 264 kfree(flashbuf); 265 #ifndef __ECOS 266 else 267 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 268 #endif 269 return ret; 270 } 271 272 int jffs2_fill_scan_buf (struct jffs2_sb_info *c, void *buf, 273 uint32_t ofs, uint32_t len) 274 { 275 int ret; 276 size_t retlen; 277 278 ret = jffs2_flash_read(c, ofs, len, &retlen, buf); 279 if (ret) { 280 D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret)); 281 return ret; 282 } 283 if (retlen < len) { 284 D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen)); 285 return -EIO; 286 } 287 return 0; 288 } 289 290 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb) 291 { 292 if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size 293 && (!jeb->first_node || !jeb->first_node->next_phys) ) 294 return BLK_STATE_CLEANMARKER; 295 296 /* move blocks with max 4 byte dirty space to cleanlist */ 297 else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) { 298 c->dirty_size -= jeb->dirty_size; 299 c->wasted_size += jeb->dirty_size; 300 jeb->wasted_size += jeb->dirty_size; 301 jeb->dirty_size = 0; 302 return BLK_STATE_CLEAN; 303 } else if (jeb->used_size || jeb->unchecked_size) 304 return BLK_STATE_PARTDIRTY; 305 else 306 return BLK_STATE_ALLDIRTY; 307 } 308 309 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 310 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) { 311 struct jffs2_unknown_node *node; 312 struct jffs2_unknown_node crcnode; 313 struct jffs2_sum_marker *sm; 314 uint32_t ofs, prevofs; 315 uint32_t hdr_crc, buf_ofs, buf_len; 316 int err; 317 int noise = 0; 318 319 320 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 321 int cleanmarkerfound = 0; 322 #endif 323 324 ofs = jeb->offset; 325 prevofs = jeb->offset - 1; 326 327 D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs)); 328 329 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 330 if (jffs2_cleanmarker_oob(c)) { 331 int ret = jffs2_check_nand_cleanmarker(c, jeb); 332 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret)); 333 /* Even if it's not found, we still scan to see 334 if the block is empty. We use this information 335 to decide whether to erase it or not. */ 336 switch (ret) { 337 case 0: cleanmarkerfound = 1; break; 338 case 1: break; 339 case 2: return BLK_STATE_BADBLOCK; 340 case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */ 341 default: return ret; 342 } 343 } 344 #endif 345 346 if (jffs2_sum_active()) { 347 sm = kmalloc(sizeof(struct jffs2_sum_marker), GFP_KERNEL); 348 if (!sm) { 349 return -ENOMEM; 350 } 351 352 err = jffs2_fill_scan_buf(c, (unsigned char *) sm, jeb->offset + c->sector_size - 353 sizeof(struct jffs2_sum_marker), sizeof(struct jffs2_sum_marker)); 354 if (err) { 355 kfree(sm); 356 return err; 357 } 358 359 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC ) { 360 err = jffs2_sum_scan_sumnode(c, jeb, je32_to_cpu(sm->offset), &pseudo_random); 361 if (err) { 362 kfree(sm); 363 return err; 364 } 365 } 366 367 kfree(sm); 368 369 ofs = jeb->offset; 370 prevofs = jeb->offset - 1; 371 } 372 373 buf_ofs = jeb->offset; 374 375 if (!buf_size) { 376 buf_len = c->sector_size; 377 378 if (jffs2_sum_active()) { 379 /* must reread because of summary test */ 380 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len); 381 if (err) 382 return err; 383 } 384 385 } else { 386 buf_len = EMPTY_SCAN_SIZE(c->sector_size); 387 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len); 388 if (err) 389 return err; 390 } 391 392 /* We temporarily use 'ofs' as a pointer into the buffer/jeb */ 393 ofs = 0; 394 395 /* Scan only 4KiB of 0xFF before declaring it's empty */ 396 while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF) 397 ofs += 4; 398 399 if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) { 400 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 401 if (jffs2_cleanmarker_oob(c)) { 402 /* scan oob, take care of cleanmarker */ 403 int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound); 404 D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret)); 405 switch (ret) { 406 case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF; 407 case 1: return BLK_STATE_ALLDIRTY; 408 default: return ret; 409 } 410 } 411 #endif 412 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset)); 413 if (c->cleanmarker_size == 0) 414 return BLK_STATE_CLEANMARKER; /* don't bother with re-erase */ 415 else 416 return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */ 417 } 418 if (ofs) { 419 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset, 420 jeb->offset + ofs)); 421 DIRTY_SPACE(ofs); 422 } 423 424 /* Now ofs is a complete physical flash offset as it always was... */ 425 ofs += jeb->offset; 426 427 noise = 10; 428 429 dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset); 430 431 scan_more: 432 while(ofs < jeb->offset + c->sector_size) { 433 434 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 435 436 cond_resched(); 437 438 if (ofs & 3) { 439 printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs); 440 ofs = PAD(ofs); 441 continue; 442 } 443 if (ofs == prevofs) { 444 printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs); 445 DIRTY_SPACE(4); 446 ofs += 4; 447 continue; 448 } 449 prevofs = ofs; 450 451 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) { 452 D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node), 453 jeb->offset, c->sector_size, ofs, sizeof(*node))); 454 DIRTY_SPACE((jeb->offset + c->sector_size)-ofs); 455 break; 456 } 457 458 if (buf_ofs + buf_len < ofs + sizeof(*node)) { 459 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 460 D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n", 461 sizeof(struct jffs2_unknown_node), buf_len, ofs)); 462 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 463 if (err) 464 return err; 465 buf_ofs = ofs; 466 } 467 468 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs]; 469 470 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) { 471 uint32_t inbuf_ofs; 472 uint32_t empty_start; 473 474 empty_start = ofs; 475 ofs += 4; 476 477 D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs)); 478 more_empty: 479 inbuf_ofs = ofs - buf_ofs; 480 while (inbuf_ofs < buf_len) { 481 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) { 482 printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n", 483 empty_start, ofs); 484 DIRTY_SPACE(ofs-empty_start); 485 goto scan_more; 486 } 487 488 inbuf_ofs+=4; 489 ofs += 4; 490 } 491 /* Ran off end. */ 492 D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs)); 493 494 /* If we're only checking the beginning of a block with a cleanmarker, 495 bail now */ 496 if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && 497 c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_phys) { 498 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size))); 499 return BLK_STATE_CLEANMARKER; 500 } 501 502 /* See how much more there is to read in this eraseblock... */ 503 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 504 if (!buf_len) { 505 /* No more to read. Break out of main loop without marking 506 this range of empty space as dirty (because it's not) */ 507 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n", 508 empty_start)); 509 break; 510 } 511 D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs)); 512 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 513 if (err) 514 return err; 515 buf_ofs = ofs; 516 goto more_empty; 517 } 518 519 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) { 520 printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs); 521 DIRTY_SPACE(4); 522 ofs += 4; 523 continue; 524 } 525 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) { 526 D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs)); 527 DIRTY_SPACE(4); 528 ofs += 4; 529 continue; 530 } 531 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) { 532 printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs); 533 printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n"); 534 DIRTY_SPACE(4); 535 ofs += 4; 536 continue; 537 } 538 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) { 539 /* OK. We're out of possibilities. Whinge and move on */ 540 noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", 541 JFFS2_MAGIC_BITMASK, ofs, 542 je16_to_cpu(node->magic)); 543 DIRTY_SPACE(4); 544 ofs += 4; 545 continue; 546 } 547 /* We seem to have a node of sorts. Check the CRC */ 548 crcnode.magic = node->magic; 549 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE); 550 crcnode.totlen = node->totlen; 551 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4); 552 553 if (hdr_crc != je32_to_cpu(node->hdr_crc)) { 554 noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n", 555 ofs, je16_to_cpu(node->magic), 556 je16_to_cpu(node->nodetype), 557 je32_to_cpu(node->totlen), 558 je32_to_cpu(node->hdr_crc), 559 hdr_crc); 560 DIRTY_SPACE(4); 561 ofs += 4; 562 continue; 563 } 564 565 if (ofs + je32_to_cpu(node->totlen) > 566 jeb->offset + c->sector_size) { 567 /* Eep. Node goes over the end of the erase block. */ 568 printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n", 569 ofs, je32_to_cpu(node->totlen)); 570 printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n"); 571 DIRTY_SPACE(4); 572 ofs += 4; 573 continue; 574 } 575 576 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) { 577 /* Wheee. This is an obsoleted node */ 578 D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs)); 579 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 580 ofs += PAD(je32_to_cpu(node->totlen)); 581 continue; 582 } 583 584 switch(je16_to_cpu(node->nodetype)) { 585 case JFFS2_NODETYPE_INODE: 586 if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) { 587 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 588 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n", 589 sizeof(struct jffs2_raw_inode), buf_len, ofs)); 590 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 591 if (err) 592 return err; 593 buf_ofs = ofs; 594 node = (void *)buf; 595 } 596 err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s); 597 if (err) return err; 598 ofs += PAD(je32_to_cpu(node->totlen)); 599 break; 600 601 case JFFS2_NODETYPE_DIRENT: 602 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { 603 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 604 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n", 605 je32_to_cpu(node->totlen), buf_len, ofs)); 606 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 607 if (err) 608 return err; 609 buf_ofs = ofs; 610 node = (void *)buf; 611 } 612 err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s); 613 if (err) return err; 614 ofs += PAD(je32_to_cpu(node->totlen)); 615 break; 616 617 case JFFS2_NODETYPE_CLEANMARKER: 618 D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs)); 619 if (je32_to_cpu(node->totlen) != c->cleanmarker_size) { 620 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 621 ofs, je32_to_cpu(node->totlen), c->cleanmarker_size); 622 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 623 ofs += PAD(sizeof(struct jffs2_unknown_node)); 624 } else if (jeb->first_node) { 625 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset); 626 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 627 ofs += PAD(sizeof(struct jffs2_unknown_node)); 628 } else { 629 struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref(); 630 if (!marker_ref) { 631 printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n"); 632 return -ENOMEM; 633 } 634 marker_ref->next_in_ino = NULL; 635 marker_ref->next_phys = NULL; 636 marker_ref->flash_offset = ofs | REF_NORMAL; 637 marker_ref->__totlen = c->cleanmarker_size; 638 jeb->first_node = jeb->last_node = marker_ref; 639 640 USED_SPACE(PAD(c->cleanmarker_size)); 641 ofs += PAD(c->cleanmarker_size); 642 } 643 break; 644 645 case JFFS2_NODETYPE_PADDING: 646 if (jffs2_sum_active()) 647 jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen)); 648 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 649 ofs += PAD(je32_to_cpu(node->totlen)); 650 break; 651 652 default: 653 switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) { 654 case JFFS2_FEATURE_ROCOMPAT: 655 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 656 c->flags |= JFFS2_SB_FLAG_RO; 657 if (!(jffs2_is_readonly(c))) 658 return -EROFS; 659 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 660 ofs += PAD(je32_to_cpu(node->totlen)); 661 break; 662 663 case JFFS2_FEATURE_INCOMPAT: 664 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 665 return -EINVAL; 666 667 case JFFS2_FEATURE_RWCOMPAT_DELETE: 668 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 669 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 670 ofs += PAD(je32_to_cpu(node->totlen)); 671 break; 672 673 case JFFS2_FEATURE_RWCOMPAT_COPY: 674 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 675 USED_SPACE(PAD(je32_to_cpu(node->totlen))); 676 ofs += PAD(je32_to_cpu(node->totlen)); 677 break; 678 } 679 } 680 } 681 682 if (jffs2_sum_active()) { 683 if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) { 684 dbg_summary("There is not enough space for " 685 "summary information, disabling for this jeb!\n"); 686 jffs2_sum_disable_collecting(s); 687 } 688 } 689 690 D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 691 jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size)); 692 693 /* mark_node_obsolete can add to wasted !! */ 694 if (jeb->wasted_size) { 695 jeb->dirty_size += jeb->wasted_size; 696 c->dirty_size += jeb->wasted_size; 697 c->wasted_size -= jeb->wasted_size; 698 jeb->wasted_size = 0; 699 } 700 701 return jffs2_scan_classify_jeb(c, jeb); 702 } 703 704 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino) 705 { 706 struct jffs2_inode_cache *ic; 707 708 ic = jffs2_get_ino_cache(c, ino); 709 if (ic) 710 return ic; 711 712 if (ino > c->highest_ino) 713 c->highest_ino = ino; 714 715 ic = jffs2_alloc_inode_cache(); 716 if (!ic) { 717 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n"); 718 return NULL; 719 } 720 memset(ic, 0, sizeof(*ic)); 721 722 ic->ino = ino; 723 ic->nodes = (void *)ic; 724 jffs2_add_ino_cache(c, ic); 725 if (ino == 1) 726 ic->nlink = 1; 727 return ic; 728 } 729 730 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 731 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s) 732 { 733 struct jffs2_raw_node_ref *raw; 734 struct jffs2_inode_cache *ic; 735 uint32_t ino = je32_to_cpu(ri->ino); 736 737 D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs)); 738 739 /* We do very little here now. Just check the ino# to which we should attribute 740 this node; we can do all the CRC checking etc. later. There's a tradeoff here -- 741 we used to scan the flash once only, reading everything we want from it into 742 memory, then building all our in-core data structures and freeing the extra 743 information. Now we allow the first part of the mount to complete a lot quicker, 744 but we have to go _back_ to the flash in order to finish the CRC checking, etc. 745 Which means that the _full_ amount of time to get to proper write mode with GC 746 operational may actually be _longer_ than before. Sucks to be me. */ 747 748 raw = jffs2_alloc_raw_node_ref(); 749 if (!raw) { 750 printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n"); 751 return -ENOMEM; 752 } 753 754 ic = jffs2_get_ino_cache(c, ino); 755 if (!ic) { 756 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the 757 first node we found for this inode. Do a CRC check to protect against the former 758 case */ 759 uint32_t crc = crc32(0, ri, sizeof(*ri)-8); 760 761 if (crc != je32_to_cpu(ri->node_crc)) { 762 printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 763 ofs, je32_to_cpu(ri->node_crc), crc); 764 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 765 DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen))); 766 jffs2_free_raw_node_ref(raw); 767 return 0; 768 } 769 ic = jffs2_scan_make_ino_cache(c, ino); 770 if (!ic) { 771 jffs2_free_raw_node_ref(raw); 772 return -ENOMEM; 773 } 774 } 775 776 /* Wheee. It worked */ 777 778 raw->flash_offset = ofs | REF_UNCHECKED; 779 raw->__totlen = PAD(je32_to_cpu(ri->totlen)); 780 raw->next_phys = NULL; 781 raw->next_in_ino = ic->nodes; 782 783 ic->nodes = raw; 784 if (!jeb->first_node) 785 jeb->first_node = raw; 786 if (jeb->last_node) 787 jeb->last_node->next_phys = raw; 788 jeb->last_node = raw; 789 790 D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n", 791 je32_to_cpu(ri->ino), je32_to_cpu(ri->version), 792 je32_to_cpu(ri->offset), 793 je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize))); 794 795 pseudo_random += je32_to_cpu(ri->version); 796 797 UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen))); 798 799 if (jffs2_sum_active()) { 800 jffs2_sum_add_inode_mem(s, ri, ofs - jeb->offset); 801 } 802 803 return 0; 804 } 805 806 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 807 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s) 808 { 809 struct jffs2_raw_node_ref *raw; 810 struct jffs2_full_dirent *fd; 811 struct jffs2_inode_cache *ic; 812 uint32_t crc; 813 814 D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs)); 815 816 /* We don't get here unless the node is still valid, so we don't have to 817 mask in the ACCURATE bit any more. */ 818 crc = crc32(0, rd, sizeof(*rd)-8); 819 820 if (crc != je32_to_cpu(rd->node_crc)) { 821 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 822 ofs, je32_to_cpu(rd->node_crc), crc); 823 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 824 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 825 return 0; 826 } 827 828 pseudo_random += je32_to_cpu(rd->version); 829 830 fd = jffs2_alloc_full_dirent(rd->nsize+1); 831 if (!fd) { 832 return -ENOMEM; 833 } 834 memcpy(&fd->name, rd->name, rd->nsize); 835 fd->name[rd->nsize] = 0; 836 837 crc = crc32(0, fd->name, rd->nsize); 838 if (crc != je32_to_cpu(rd->name_crc)) { 839 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 840 ofs, je32_to_cpu(rd->name_crc), crc); 841 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino))); 842 jffs2_free_full_dirent(fd); 843 /* FIXME: Why do we believe totlen? */ 844 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */ 845 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 846 return 0; 847 } 848 raw = jffs2_alloc_raw_node_ref(); 849 if (!raw) { 850 jffs2_free_full_dirent(fd); 851 printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n"); 852 return -ENOMEM; 853 } 854 ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino)); 855 if (!ic) { 856 jffs2_free_full_dirent(fd); 857 jffs2_free_raw_node_ref(raw); 858 return -ENOMEM; 859 } 860 861 raw->__totlen = PAD(je32_to_cpu(rd->totlen)); 862 raw->flash_offset = ofs | REF_PRISTINE; 863 raw->next_phys = NULL; 864 raw->next_in_ino = ic->nodes; 865 ic->nodes = raw; 866 if (!jeb->first_node) 867 jeb->first_node = raw; 868 if (jeb->last_node) 869 jeb->last_node->next_phys = raw; 870 jeb->last_node = raw; 871 872 fd->raw = raw; 873 fd->next = NULL; 874 fd->version = je32_to_cpu(rd->version); 875 fd->ino = je32_to_cpu(rd->ino); 876 fd->nhash = full_name_hash(fd->name, rd->nsize); 877 fd->type = rd->type; 878 USED_SPACE(PAD(je32_to_cpu(rd->totlen))); 879 jffs2_add_fd_to_list(c, fd, &ic->scan_dents); 880 881 if (jffs2_sum_active()) { 882 jffs2_sum_add_dirent_mem(s, rd, ofs - jeb->offset); 883 } 884 885 return 0; 886 } 887 888 static int count_list(struct list_head *l) 889 { 890 uint32_t count = 0; 891 struct list_head *tmp; 892 893 list_for_each(tmp, l) { 894 count++; 895 } 896 return count; 897 } 898 899 /* Note: This breaks if list_empty(head). I don't care. You 900 might, if you copy this code and use it elsewhere :) */ 901 static void rotate_list(struct list_head *head, uint32_t count) 902 { 903 struct list_head *n = head->next; 904 905 list_del(head); 906 while(count--) { 907 n = n->next; 908 } 909 list_add(head, n); 910 } 911 912 void jffs2_rotate_lists(struct jffs2_sb_info *c) 913 { 914 uint32_t x; 915 uint32_t rotateby; 916 917 x = count_list(&c->clean_list); 918 if (x) { 919 rotateby = pseudo_random % x; 920 rotate_list((&c->clean_list), rotateby); 921 } 922 923 x = count_list(&c->very_dirty_list); 924 if (x) { 925 rotateby = pseudo_random % x; 926 rotate_list((&c->very_dirty_list), rotateby); 927 } 928 929 x = count_list(&c->dirty_list); 930 if (x) { 931 rotateby = pseudo_random % x; 932 rotate_list((&c->dirty_list), rotateby); 933 } 934 935 x = count_list(&c->erasable_list); 936 if (x) { 937 rotateby = pseudo_random % x; 938 rotate_list((&c->erasable_list), rotateby); 939 } 940 941 if (c->nr_erasing_blocks) { 942 rotateby = pseudo_random % c->nr_erasing_blocks; 943 rotate_list((&c->erase_pending_list), rotateby); 944 } 945 946 if (c->nr_free_blocks) { 947 rotateby = pseudo_random % c->nr_free_blocks; 948 rotate_list((&c->free_list), rotateby); 949 } 950 } 951