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 /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */ 226 if (c->nextblock && (c->nextblock->dirty_size)) { 227 c->nextblock->wasted_size += c->nextblock->dirty_size; 228 c->wasted_size += c->nextblock->dirty_size; 229 c->dirty_size -= c->nextblock->dirty_size; 230 c->nextblock->dirty_size = 0; 231 } 232 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 233 if (!jffs2_can_mark_obsolete(c) && c->wbuf_pagesize && c->nextblock && (c->nextblock->free_size % c->wbuf_pagesize)) { 234 /* If we're going to start writing into a block which already 235 contains data, and the end of the data isn't page-aligned, 236 skip a little and align it. */ 237 238 uint32_t skip = c->nextblock->free_size % c->wbuf_pagesize; 239 240 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n", 241 skip)); 242 c->nextblock->wasted_size += skip; 243 c->wasted_size += skip; 244 245 c->nextblock->free_size -= skip; 246 c->free_size -= skip; 247 } 248 #endif 249 if (c->nr_erasing_blocks) { 250 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) { 251 printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n"); 252 printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks); 253 ret = -EIO; 254 goto out; 255 } 256 jffs2_erase_pending_trigger(c); 257 } 258 ret = 0; 259 out: 260 if (buf_size) 261 kfree(flashbuf); 262 #ifndef __ECOS 263 else 264 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 265 #endif 266 if (s) 267 kfree(s); 268 269 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 /* Called with 'buf_size == 0' if buf is in fact a pointer _directly_ into 310 the flash, XIP-style */ 311 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 312 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) { 313 struct jffs2_unknown_node *node; 314 struct jffs2_unknown_node crcnode; 315 uint32_t ofs, prevofs; 316 uint32_t hdr_crc, buf_ofs, buf_len; 317 int err; 318 int noise = 0; 319 320 321 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 322 int cleanmarkerfound = 0; 323 #endif 324 325 ofs = jeb->offset; 326 prevofs = jeb->offset - 1; 327 328 D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs)); 329 330 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 331 if (jffs2_cleanmarker_oob(c)) { 332 int ret = jffs2_check_nand_cleanmarker(c, jeb); 333 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret)); 334 /* Even if it's not found, we still scan to see 335 if the block is empty. We use this information 336 to decide whether to erase it or not. */ 337 switch (ret) { 338 case 0: cleanmarkerfound = 1; break; 339 case 1: break; 340 case 2: return BLK_STATE_BADBLOCK; 341 case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */ 342 default: return ret; 343 } 344 } 345 #endif 346 347 if (jffs2_sum_active()) { 348 struct jffs2_sum_marker *sm; 349 void *sumptr = NULL; 350 uint32_t sumlen; 351 352 if (!buf_size) { 353 /* XIP case. Just look, point at the summary if it's there */ 354 sm = (void *)buf + jeb->offset - sizeof(*sm); 355 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) { 356 sumptr = buf + je32_to_cpu(sm->offset); 357 sumlen = c->sector_size - je32_to_cpu(sm->offset); 358 } 359 } else { 360 /* If NAND flash, read a whole page of it. Else just the end */ 361 if (c->wbuf_pagesize) 362 buf_len = c->wbuf_pagesize; 363 else 364 buf_len = sizeof(*sm); 365 366 /* Read as much as we want into the _end_ of the preallocated buffer */ 367 err = jffs2_fill_scan_buf(c, buf + buf_size - buf_len, 368 jeb->offset + c->sector_size - buf_len, 369 buf_len); 370 if (err) 371 return err; 372 373 sm = (void *)buf + buf_size - sizeof(*sm); 374 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) { 375 sumlen = c->sector_size - je32_to_cpu(sm->offset); 376 sumptr = buf + buf_size - sumlen; 377 378 /* Now, make sure the summary itself is available */ 379 if (sumlen > buf_size) { 380 /* Need to kmalloc for this. */ 381 sumptr = kmalloc(sumlen, GFP_KERNEL); 382 if (!sumptr) 383 return -ENOMEM; 384 memcpy(sumptr + sumlen - buf_len, buf + buf_size - buf_len, buf_len); 385 } 386 if (buf_len < sumlen) { 387 /* Need to read more so that the entire summary node is present */ 388 err = jffs2_fill_scan_buf(c, sumptr, 389 jeb->offset + c->sector_size - sumlen, 390 sumlen - buf_len); 391 if (err) 392 return err; 393 } 394 } 395 396 } 397 398 if (sumptr) { 399 err = jffs2_sum_scan_sumnode(c, jeb, sumptr, sumlen, &pseudo_random); 400 if (err) 401 return err; 402 if (buf_size && sumlen > buf_size) 403 kfree(sumptr); 404 } 405 } 406 407 buf_ofs = jeb->offset; 408 409 if (!buf_size) { 410 /* This is the XIP case -- we're reading _directly_ from the flash chip */ 411 buf_len = c->sector_size; 412 } else { 413 buf_len = EMPTY_SCAN_SIZE(c->sector_size); 414 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len); 415 if (err) 416 return err; 417 } 418 419 /* We temporarily use 'ofs' as a pointer into the buffer/jeb */ 420 ofs = 0; 421 422 /* Scan only 4KiB of 0xFF before declaring it's empty */ 423 while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF) 424 ofs += 4; 425 426 if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) { 427 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 428 if (jffs2_cleanmarker_oob(c)) { 429 /* scan oob, take care of cleanmarker */ 430 int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound); 431 D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret)); 432 switch (ret) { 433 case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF; 434 case 1: return BLK_STATE_ALLDIRTY; 435 default: return ret; 436 } 437 } 438 #endif 439 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset)); 440 if (c->cleanmarker_size == 0) 441 return BLK_STATE_CLEANMARKER; /* don't bother with re-erase */ 442 else 443 return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */ 444 } 445 if (ofs) { 446 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset, 447 jeb->offset + ofs)); 448 DIRTY_SPACE(ofs); 449 } 450 451 /* Now ofs is a complete physical flash offset as it always was... */ 452 ofs += jeb->offset; 453 454 noise = 10; 455 456 dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset); 457 458 scan_more: 459 while(ofs < jeb->offset + c->sector_size) { 460 461 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 462 463 cond_resched(); 464 465 if (ofs & 3) { 466 printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs); 467 ofs = PAD(ofs); 468 continue; 469 } 470 if (ofs == prevofs) { 471 printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs); 472 DIRTY_SPACE(4); 473 ofs += 4; 474 continue; 475 } 476 prevofs = ofs; 477 478 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) { 479 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), 480 jeb->offset, c->sector_size, ofs, sizeof(*node))); 481 DIRTY_SPACE((jeb->offset + c->sector_size)-ofs); 482 break; 483 } 484 485 if (buf_ofs + buf_len < ofs + sizeof(*node)) { 486 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 487 D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n", 488 sizeof(struct jffs2_unknown_node), buf_len, ofs)); 489 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 490 if (err) 491 return err; 492 buf_ofs = ofs; 493 } 494 495 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs]; 496 497 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) { 498 uint32_t inbuf_ofs; 499 uint32_t empty_start; 500 501 empty_start = ofs; 502 ofs += 4; 503 504 D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs)); 505 more_empty: 506 inbuf_ofs = ofs - buf_ofs; 507 while (inbuf_ofs < buf_len) { 508 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) { 509 printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n", 510 empty_start, ofs); 511 DIRTY_SPACE(ofs-empty_start); 512 goto scan_more; 513 } 514 515 inbuf_ofs+=4; 516 ofs += 4; 517 } 518 /* Ran off end. */ 519 D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs)); 520 521 /* If we're only checking the beginning of a block with a cleanmarker, 522 bail now */ 523 if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && 524 c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_phys) { 525 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size))); 526 return BLK_STATE_CLEANMARKER; 527 } 528 529 /* See how much more there is to read in this eraseblock... */ 530 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 531 if (!buf_len) { 532 /* No more to read. Break out of main loop without marking 533 this range of empty space as dirty (because it's not) */ 534 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n", 535 empty_start)); 536 break; 537 } 538 D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs)); 539 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 540 if (err) 541 return err; 542 buf_ofs = ofs; 543 goto more_empty; 544 } 545 546 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) { 547 printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs); 548 DIRTY_SPACE(4); 549 ofs += 4; 550 continue; 551 } 552 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) { 553 D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs)); 554 DIRTY_SPACE(4); 555 ofs += 4; 556 continue; 557 } 558 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) { 559 printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs); 560 printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n"); 561 DIRTY_SPACE(4); 562 ofs += 4; 563 continue; 564 } 565 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) { 566 /* OK. We're out of possibilities. Whinge and move on */ 567 noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", 568 JFFS2_MAGIC_BITMASK, ofs, 569 je16_to_cpu(node->magic)); 570 DIRTY_SPACE(4); 571 ofs += 4; 572 continue; 573 } 574 /* We seem to have a node of sorts. Check the CRC */ 575 crcnode.magic = node->magic; 576 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE); 577 crcnode.totlen = node->totlen; 578 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4); 579 580 if (hdr_crc != je32_to_cpu(node->hdr_crc)) { 581 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", 582 ofs, je16_to_cpu(node->magic), 583 je16_to_cpu(node->nodetype), 584 je32_to_cpu(node->totlen), 585 je32_to_cpu(node->hdr_crc), 586 hdr_crc); 587 DIRTY_SPACE(4); 588 ofs += 4; 589 continue; 590 } 591 592 if (ofs + je32_to_cpu(node->totlen) > 593 jeb->offset + c->sector_size) { 594 /* Eep. Node goes over the end of the erase block. */ 595 printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n", 596 ofs, je32_to_cpu(node->totlen)); 597 printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n"); 598 DIRTY_SPACE(4); 599 ofs += 4; 600 continue; 601 } 602 603 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) { 604 /* Wheee. This is an obsoleted node */ 605 D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs)); 606 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 607 ofs += PAD(je32_to_cpu(node->totlen)); 608 continue; 609 } 610 611 switch(je16_to_cpu(node->nodetype)) { 612 case JFFS2_NODETYPE_INODE: 613 if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) { 614 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 615 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n", 616 sizeof(struct jffs2_raw_inode), buf_len, ofs)); 617 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 618 if (err) 619 return err; 620 buf_ofs = ofs; 621 node = (void *)buf; 622 } 623 err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s); 624 if (err) return err; 625 ofs += PAD(je32_to_cpu(node->totlen)); 626 break; 627 628 case JFFS2_NODETYPE_DIRENT: 629 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { 630 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 631 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n", 632 je32_to_cpu(node->totlen), buf_len, ofs)); 633 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 634 if (err) 635 return err; 636 buf_ofs = ofs; 637 node = (void *)buf; 638 } 639 err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s); 640 if (err) return err; 641 ofs += PAD(je32_to_cpu(node->totlen)); 642 break; 643 644 case JFFS2_NODETYPE_CLEANMARKER: 645 D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs)); 646 if (je32_to_cpu(node->totlen) != c->cleanmarker_size) { 647 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 648 ofs, je32_to_cpu(node->totlen), c->cleanmarker_size); 649 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 650 ofs += PAD(sizeof(struct jffs2_unknown_node)); 651 } else if (jeb->first_node) { 652 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset); 653 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 654 ofs += PAD(sizeof(struct jffs2_unknown_node)); 655 } else { 656 struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref(); 657 if (!marker_ref) { 658 printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n"); 659 return -ENOMEM; 660 } 661 marker_ref->next_in_ino = NULL; 662 marker_ref->next_phys = NULL; 663 marker_ref->flash_offset = ofs | REF_NORMAL; 664 marker_ref->__totlen = c->cleanmarker_size; 665 jeb->first_node = jeb->last_node = marker_ref; 666 667 USED_SPACE(PAD(c->cleanmarker_size)); 668 ofs += PAD(c->cleanmarker_size); 669 } 670 break; 671 672 case JFFS2_NODETYPE_PADDING: 673 if (jffs2_sum_active()) 674 jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen)); 675 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 676 ofs += PAD(je32_to_cpu(node->totlen)); 677 break; 678 679 default: 680 switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) { 681 case JFFS2_FEATURE_ROCOMPAT: 682 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 683 c->flags |= JFFS2_SB_FLAG_RO; 684 if (!(jffs2_is_readonly(c))) 685 return -EROFS; 686 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 687 ofs += PAD(je32_to_cpu(node->totlen)); 688 break; 689 690 case JFFS2_FEATURE_INCOMPAT: 691 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 692 return -EINVAL; 693 694 case JFFS2_FEATURE_RWCOMPAT_DELETE: 695 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 696 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 697 ofs += PAD(je32_to_cpu(node->totlen)); 698 break; 699 700 case JFFS2_FEATURE_RWCOMPAT_COPY: 701 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 702 USED_SPACE(PAD(je32_to_cpu(node->totlen))); 703 ofs += PAD(je32_to_cpu(node->totlen)); 704 break; 705 } 706 } 707 } 708 709 if (jffs2_sum_active()) { 710 if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) { 711 dbg_summary("There is not enough space for " 712 "summary information, disabling for this jeb!\n"); 713 jffs2_sum_disable_collecting(s); 714 } 715 } 716 717 D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 718 jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size)); 719 720 /* mark_node_obsolete can add to wasted !! */ 721 if (jeb->wasted_size) { 722 jeb->dirty_size += jeb->wasted_size; 723 c->dirty_size += jeb->wasted_size; 724 c->wasted_size -= jeb->wasted_size; 725 jeb->wasted_size = 0; 726 } 727 728 return jffs2_scan_classify_jeb(c, jeb); 729 } 730 731 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino) 732 { 733 struct jffs2_inode_cache *ic; 734 735 ic = jffs2_get_ino_cache(c, ino); 736 if (ic) 737 return ic; 738 739 if (ino > c->highest_ino) 740 c->highest_ino = ino; 741 742 ic = jffs2_alloc_inode_cache(); 743 if (!ic) { 744 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n"); 745 return NULL; 746 } 747 memset(ic, 0, sizeof(*ic)); 748 749 ic->ino = ino; 750 ic->nodes = (void *)ic; 751 jffs2_add_ino_cache(c, ic); 752 if (ino == 1) 753 ic->nlink = 1; 754 return ic; 755 } 756 757 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 758 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s) 759 { 760 struct jffs2_raw_node_ref *raw; 761 struct jffs2_inode_cache *ic; 762 uint32_t ino = je32_to_cpu(ri->ino); 763 764 D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs)); 765 766 /* We do very little here now. Just check the ino# to which we should attribute 767 this node; we can do all the CRC checking etc. later. There's a tradeoff here -- 768 we used to scan the flash once only, reading everything we want from it into 769 memory, then building all our in-core data structures and freeing the extra 770 information. Now we allow the first part of the mount to complete a lot quicker, 771 but we have to go _back_ to the flash in order to finish the CRC checking, etc. 772 Which means that the _full_ amount of time to get to proper write mode with GC 773 operational may actually be _longer_ than before. Sucks to be me. */ 774 775 raw = jffs2_alloc_raw_node_ref(); 776 if (!raw) { 777 printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n"); 778 return -ENOMEM; 779 } 780 781 ic = jffs2_get_ino_cache(c, ino); 782 if (!ic) { 783 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the 784 first node we found for this inode. Do a CRC check to protect against the former 785 case */ 786 uint32_t crc = crc32(0, ri, sizeof(*ri)-8); 787 788 if (crc != je32_to_cpu(ri->node_crc)) { 789 printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 790 ofs, je32_to_cpu(ri->node_crc), crc); 791 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 792 DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen))); 793 jffs2_free_raw_node_ref(raw); 794 return 0; 795 } 796 ic = jffs2_scan_make_ino_cache(c, ino); 797 if (!ic) { 798 jffs2_free_raw_node_ref(raw); 799 return -ENOMEM; 800 } 801 } 802 803 /* Wheee. It worked */ 804 805 raw->flash_offset = ofs | REF_UNCHECKED; 806 raw->__totlen = PAD(je32_to_cpu(ri->totlen)); 807 raw->next_phys = NULL; 808 raw->next_in_ino = ic->nodes; 809 810 ic->nodes = raw; 811 if (!jeb->first_node) 812 jeb->first_node = raw; 813 if (jeb->last_node) 814 jeb->last_node->next_phys = raw; 815 jeb->last_node = raw; 816 817 D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n", 818 je32_to_cpu(ri->ino), je32_to_cpu(ri->version), 819 je32_to_cpu(ri->offset), 820 je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize))); 821 822 pseudo_random += je32_to_cpu(ri->version); 823 824 UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen))); 825 826 if (jffs2_sum_active()) { 827 jffs2_sum_add_inode_mem(s, ri, ofs - jeb->offset); 828 } 829 830 return 0; 831 } 832 833 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 834 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s) 835 { 836 struct jffs2_raw_node_ref *raw; 837 struct jffs2_full_dirent *fd; 838 struct jffs2_inode_cache *ic; 839 uint32_t crc; 840 841 D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs)); 842 843 /* We don't get here unless the node is still valid, so we don't have to 844 mask in the ACCURATE bit any more. */ 845 crc = crc32(0, rd, sizeof(*rd)-8); 846 847 if (crc != je32_to_cpu(rd->node_crc)) { 848 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 849 ofs, je32_to_cpu(rd->node_crc), crc); 850 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 851 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 852 return 0; 853 } 854 855 pseudo_random += je32_to_cpu(rd->version); 856 857 fd = jffs2_alloc_full_dirent(rd->nsize+1); 858 if (!fd) { 859 return -ENOMEM; 860 } 861 memcpy(&fd->name, rd->name, rd->nsize); 862 fd->name[rd->nsize] = 0; 863 864 crc = crc32(0, fd->name, rd->nsize); 865 if (crc != je32_to_cpu(rd->name_crc)) { 866 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 867 ofs, je32_to_cpu(rd->name_crc), crc); 868 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino))); 869 jffs2_free_full_dirent(fd); 870 /* FIXME: Why do we believe totlen? */ 871 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */ 872 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 873 return 0; 874 } 875 raw = jffs2_alloc_raw_node_ref(); 876 if (!raw) { 877 jffs2_free_full_dirent(fd); 878 printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n"); 879 return -ENOMEM; 880 } 881 ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino)); 882 if (!ic) { 883 jffs2_free_full_dirent(fd); 884 jffs2_free_raw_node_ref(raw); 885 return -ENOMEM; 886 } 887 888 raw->__totlen = PAD(je32_to_cpu(rd->totlen)); 889 raw->flash_offset = ofs | REF_PRISTINE; 890 raw->next_phys = NULL; 891 raw->next_in_ino = ic->nodes; 892 ic->nodes = raw; 893 if (!jeb->first_node) 894 jeb->first_node = raw; 895 if (jeb->last_node) 896 jeb->last_node->next_phys = raw; 897 jeb->last_node = raw; 898 899 fd->raw = raw; 900 fd->next = NULL; 901 fd->version = je32_to_cpu(rd->version); 902 fd->ino = je32_to_cpu(rd->ino); 903 fd->nhash = full_name_hash(fd->name, rd->nsize); 904 fd->type = rd->type; 905 USED_SPACE(PAD(je32_to_cpu(rd->totlen))); 906 jffs2_add_fd_to_list(c, fd, &ic->scan_dents); 907 908 if (jffs2_sum_active()) { 909 jffs2_sum_add_dirent_mem(s, rd, ofs - jeb->offset); 910 } 911 912 return 0; 913 } 914 915 static int count_list(struct list_head *l) 916 { 917 uint32_t count = 0; 918 struct list_head *tmp; 919 920 list_for_each(tmp, l) { 921 count++; 922 } 923 return count; 924 } 925 926 /* Note: This breaks if list_empty(head). I don't care. You 927 might, if you copy this code and use it elsewhere :) */ 928 static void rotate_list(struct list_head *head, uint32_t count) 929 { 930 struct list_head *n = head->next; 931 932 list_del(head); 933 while(count--) { 934 n = n->next; 935 } 936 list_add(head, n); 937 } 938 939 void jffs2_rotate_lists(struct jffs2_sb_info *c) 940 { 941 uint32_t x; 942 uint32_t rotateby; 943 944 x = count_list(&c->clean_list); 945 if (x) { 946 rotateby = pseudo_random % x; 947 rotate_list((&c->clean_list), rotateby); 948 } 949 950 x = count_list(&c->very_dirty_list); 951 if (x) { 952 rotateby = pseudo_random % x; 953 rotate_list((&c->very_dirty_list), rotateby); 954 } 955 956 x = count_list(&c->dirty_list); 957 if (x) { 958 rotateby = pseudo_random % x; 959 rotate_list((&c->dirty_list), rotateby); 960 } 961 962 x = count_list(&c->erasable_list); 963 if (x) { 964 rotateby = pseudo_random % x; 965 rotate_list((&c->erasable_list), rotateby); 966 } 967 968 if (c->nr_erasing_blocks) { 969 rotateby = pseudo_random % c->nr_erasing_blocks; 970 rotate_list((&c->erase_pending_list), rotateby); 971 } 972 973 if (c->nr_free_blocks) { 974 rotateby = pseudo_random % c->nr_free_blocks; 975 rotate_list((&c->free_list), rotateby); 976 } 977 } 978