1 /* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright (C) 2001-2003 Red Hat, Inc. 5 * 6 * Created by David Woodhouse <[email protected]> 7 * 8 * For licensing information, see the file 'LICENCE' in this directory. 9 * 10 * $Id: scan.c,v 1.121 2005/07/20 15:32:28 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 22 #define DEFAULT_EMPTY_SCAN_SIZE 1024 23 24 #if defined (__GNUC__) 25 #elif defined (MSVC) 26 #define typeof(x) uint32_t 27 #else 28 #endif 29 30 #define DIRTY_SPACE(x) do { typeof(x) _x = (x); \ 31 c->free_size -= _x; c->dirty_size += _x; \ 32 jeb->free_size -= _x ; jeb->dirty_size += _x; \ 33 }while(0) 34 #define USED_SPACE(x) do { typeof(x) _x = (x); \ 35 c->free_size -= _x; c->used_size += _x; \ 36 jeb->free_size -= _x ; jeb->used_size += _x; \ 37 }while(0) 38 #define UNCHECKED_SPACE(x) do { typeof(x) _x = (x); \ 39 c->free_size -= _x; c->unchecked_size += _x; \ 40 jeb->free_size -= _x ; jeb->unchecked_size += _x; \ 41 }while(0) 42 43 #if defined (__GNUC__) 44 #define noisy_printk(noise, args...) do { \ 45 if (*(noise)) { \ 46 printk(KERN_NOTICE args); \ 47 (*(noise))--; \ 48 if (!(*(noise))) { \ 49 printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \ 50 } \ 51 } \ 52 } while(0) 53 #elif defined (MSVC) 54 #define noisy_printk(noise, ...) do { \ 55 if (*(noise)) { \ 56 printk(KERN_NOTICE ##__VA_ARGS__); \ 57 (*(noise))--; \ 58 if (!(*(noise))) { \ 59 printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \ 60 } \ 61 } \ 62 } while(0) 63 #else 64 #endif 65 66 static uint32_t pseudo_random; 67 68 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 69 unsigned char *buf, uint32_t buf_size); 70 71 /* These helper functions _must_ increase ofs and also do the dirty/used space accounting. 72 * Returning an error will abort the mount - bad checksums etc. should just mark the space 73 * as dirty. 74 */ 75 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 76 struct jffs2_raw_inode *ri, uint32_t ofs); 77 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 78 struct jffs2_raw_dirent *rd, uint32_t ofs); 79 80 #define BLK_STATE_ALLFF 0 81 #define BLK_STATE_CLEAN 1 82 #define BLK_STATE_PARTDIRTY 2 83 #define BLK_STATE_CLEANMARKER 3 84 #define BLK_STATE_ALLDIRTY 4 85 #define BLK_STATE_BADBLOCK 5 86 87 static inline int min_free(struct jffs2_sb_info *c) 88 { 89 uint32_t min = 2 * sizeof(struct jffs2_raw_inode); 90 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 91 if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize) 92 return c->wbuf_pagesize; 93 #endif 94 return min; 95 96 } 97 98 static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size) { 99 if (sector_size < DEFAULT_EMPTY_SCAN_SIZE) 100 return sector_size; 101 else 102 return DEFAULT_EMPTY_SCAN_SIZE; 103 } 104 105 int jffs2_scan_medium(struct jffs2_sb_info *c) 106 { 107 int i, ret; 108 uint32_t empty_blocks = 0, bad_blocks = 0; 109 unsigned char *flashbuf = NULL; 110 uint32_t buf_size = 0; 111 #ifndef __ECOS 112 size_t pointlen; 113 114 if (c->mtd->point) { 115 ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf); 116 if (!ret && pointlen < c->mtd->size) { 117 /* Don't muck about if it won't let us point to the whole flash */ 118 D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen)); 119 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 120 flashbuf = NULL; 121 } 122 if (ret) 123 D1(printk(KERN_DEBUG "MTD point failed %d\n", ret)); 124 } 125 #endif 126 if (!flashbuf) { 127 /* For NAND it's quicker to read a whole eraseblock at a time, 128 apparently */ 129 if (jffs2_cleanmarker_oob(c)) 130 buf_size = c->sector_size; 131 else 132 buf_size = PAGE_SIZE; 133 134 /* Respect kmalloc limitations */ 135 if (buf_size > 128*1024) 136 buf_size = 128*1024; 137 138 D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size)); 139 flashbuf = kmalloc(buf_size, GFP_KERNEL); 140 if (!flashbuf) 141 return -ENOMEM; 142 } 143 144 for (i=0; i<c->nr_blocks; i++) { 145 struct jffs2_eraseblock *jeb = &c->blocks[i]; 146 147 ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset), buf_size); 148 149 if (ret < 0) 150 goto out; 151 152 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 153 154 /* Now decide which list to put it on */ 155 switch(ret) { 156 case BLK_STATE_ALLFF: 157 /* 158 * Empty block. Since we can't be sure it 159 * was entirely erased, we just queue it for erase 160 * again. It will be marked as such when the erase 161 * is complete. Meanwhile we still count it as empty 162 * for later checks. 163 */ 164 empty_blocks++; 165 list_add(&jeb->list, &c->erase_pending_list); 166 c->nr_erasing_blocks++; 167 break; 168 169 case BLK_STATE_CLEANMARKER: 170 /* Only a CLEANMARKER node is valid */ 171 if (!jeb->dirty_size) { 172 /* It's actually free */ 173 list_add(&jeb->list, &c->free_list); 174 c->nr_free_blocks++; 175 } else { 176 /* Dirt */ 177 D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset)); 178 list_add(&jeb->list, &c->erase_pending_list); 179 c->nr_erasing_blocks++; 180 } 181 break; 182 183 case BLK_STATE_CLEAN: 184 /* Full (or almost full) of clean data. Clean list */ 185 list_add(&jeb->list, &c->clean_list); 186 break; 187 188 case BLK_STATE_PARTDIRTY: 189 /* Some data, but not full. Dirty list. */ 190 /* We want to remember the block with most free space 191 and stick it in the 'nextblock' position to start writing to it. */ 192 if (jeb->free_size > min_free(c) && 193 (!c->nextblock || c->nextblock->free_size < jeb->free_size)) { 194 /* Better candidate for the next writes to go to */ 195 if (c->nextblock) { 196 c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; 197 c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; 198 c->free_size -= c->nextblock->free_size; 199 c->wasted_size -= c->nextblock->wasted_size; 200 c->nextblock->free_size = c->nextblock->wasted_size = 0; 201 if (VERYDIRTY(c, c->nextblock->dirty_size)) { 202 list_add(&c->nextblock->list, &c->very_dirty_list); 203 } else { 204 list_add(&c->nextblock->list, &c->dirty_list); 205 } 206 } 207 c->nextblock = jeb; 208 } else { 209 jeb->dirty_size += jeb->free_size + jeb->wasted_size; 210 c->dirty_size += jeb->free_size + jeb->wasted_size; 211 c->free_size -= jeb->free_size; 212 c->wasted_size -= jeb->wasted_size; 213 jeb->free_size = jeb->wasted_size = 0; 214 if (VERYDIRTY(c, jeb->dirty_size)) { 215 list_add(&jeb->list, &c->very_dirty_list); 216 } else { 217 list_add(&jeb->list, &c->dirty_list); 218 } 219 } 220 break; 221 222 case BLK_STATE_ALLDIRTY: 223 /* Nothing valid - not even a clean marker. Needs erasing. */ 224 /* For now we just put it on the erasing list. We'll start the erases later */ 225 D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset)); 226 list_add(&jeb->list, &c->erase_pending_list); 227 c->nr_erasing_blocks++; 228 break; 229 230 case BLK_STATE_BADBLOCK: 231 D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset)); 232 list_add(&jeb->list, &c->bad_list); 233 c->bad_size += c->sector_size; 234 c->free_size -= c->sector_size; 235 bad_blocks++; 236 break; 237 default: 238 printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n"); 239 BUG(); 240 } 241 } 242 243 /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */ 244 if (c->nextblock && (c->nextblock->dirty_size)) { 245 c->nextblock->wasted_size += c->nextblock->dirty_size; 246 c->wasted_size += c->nextblock->dirty_size; 247 c->dirty_size -= c->nextblock->dirty_size; 248 c->nextblock->dirty_size = 0; 249 } 250 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 251 if (!jffs2_can_mark_obsolete(c) && c->nextblock && (c->nextblock->free_size & (c->wbuf_pagesize-1))) { 252 /* If we're going to start writing into a block which already 253 contains data, and the end of the data isn't page-aligned, 254 skip a little and align it. */ 255 256 uint32_t skip = c->nextblock->free_size & (c->wbuf_pagesize-1); 257 258 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n", 259 skip)); 260 c->nextblock->wasted_size += skip; 261 c->wasted_size += skip; 262 263 c->nextblock->free_size -= skip; 264 c->free_size -= skip; 265 } 266 #endif 267 if (c->nr_erasing_blocks) { 268 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) { 269 printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n"); 270 printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks); 271 ret = -EIO; 272 goto out; 273 } 274 jffs2_erase_pending_trigger(c); 275 } 276 ret = 0; 277 out: 278 if (buf_size) 279 kfree(flashbuf); 280 #ifndef __ECOS 281 else 282 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 283 #endif 284 return ret; 285 } 286 287 static int jffs2_fill_scan_buf (struct jffs2_sb_info *c, unsigned char *buf, 288 uint32_t ofs, uint32_t len) 289 { 290 int ret; 291 size_t retlen; 292 293 ret = jffs2_flash_read(c, ofs, len, &retlen, buf); 294 if (ret) { 295 D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret)); 296 return ret; 297 } 298 if (retlen < len) { 299 D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen)); 300 return -EIO; 301 } 302 D2(printk(KERN_DEBUG "Read 0x%x bytes from 0x%08x into buf\n", len, ofs)); 303 D2(printk(KERN_DEBUG "000: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n", 304 buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7], buf[8], buf[9], buf[10], buf[11], buf[12], buf[13], buf[14], buf[15])); 305 return 0; 306 } 307 308 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 309 unsigned char *buf, uint32_t buf_size) { 310 struct jffs2_unknown_node *node; 311 struct jffs2_unknown_node crcnode; 312 uint32_t ofs, prevofs; 313 uint32_t hdr_crc, buf_ofs, buf_len; 314 int err; 315 int noise = 0; 316 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 317 int cleanmarkerfound = 0; 318 #endif 319 320 ofs = jeb->offset; 321 prevofs = jeb->offset - 1; 322 323 D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs)); 324 325 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 326 if (jffs2_cleanmarker_oob(c)) { 327 int ret = jffs2_check_nand_cleanmarker(c, jeb); 328 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret)); 329 /* Even if it's not found, we still scan to see 330 if the block is empty. We use this information 331 to decide whether to erase it or not. */ 332 switch (ret) { 333 case 0: cleanmarkerfound = 1; break; 334 case 1: break; 335 case 2: return BLK_STATE_BADBLOCK; 336 case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */ 337 default: return ret; 338 } 339 } 340 #endif 341 buf_ofs = jeb->offset; 342 343 if (!buf_size) { 344 buf_len = c->sector_size; 345 } else { 346 buf_len = EMPTY_SCAN_SIZE(c->sector_size); 347 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len); 348 if (err) 349 return err; 350 } 351 352 /* We temporarily use 'ofs' as a pointer into the buffer/jeb */ 353 ofs = 0; 354 355 /* Scan only 4KiB of 0xFF before declaring it's empty */ 356 while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF) 357 ofs += 4; 358 359 if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) { 360 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 361 if (jffs2_cleanmarker_oob(c)) { 362 /* scan oob, take care of cleanmarker */ 363 int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound); 364 D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret)); 365 switch (ret) { 366 case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF; 367 case 1: return BLK_STATE_ALLDIRTY; 368 default: return ret; 369 } 370 } 371 #endif 372 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset)); 373 if (c->cleanmarker_size == 0) 374 return BLK_STATE_CLEANMARKER; /* don't bother with re-erase */ 375 else 376 return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */ 377 } 378 if (ofs) { 379 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset, 380 jeb->offset + ofs)); 381 DIRTY_SPACE(ofs); 382 } 383 384 /* Now ofs is a complete physical flash offset as it always was... */ 385 ofs += jeb->offset; 386 387 noise = 10; 388 389 scan_more: 390 while(ofs < jeb->offset + c->sector_size) { 391 392 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 393 394 cond_resched(); 395 396 if (ofs & 3) { 397 printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs); 398 ofs = PAD(ofs); 399 continue; 400 } 401 if (ofs == prevofs) { 402 printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs); 403 DIRTY_SPACE(4); 404 ofs += 4; 405 continue; 406 } 407 prevofs = ofs; 408 409 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) { 410 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), 411 jeb->offset, c->sector_size, ofs, sizeof(*node))); 412 DIRTY_SPACE((jeb->offset + c->sector_size)-ofs); 413 break; 414 } 415 416 if (buf_ofs + buf_len < ofs + sizeof(*node)) { 417 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 418 D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n", 419 sizeof(struct jffs2_unknown_node), buf_len, ofs)); 420 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 421 if (err) 422 return err; 423 buf_ofs = ofs; 424 } 425 426 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs]; 427 428 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) { 429 uint32_t inbuf_ofs; 430 uint32_t empty_start; 431 432 empty_start = ofs; 433 ofs += 4; 434 435 D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs)); 436 more_empty: 437 inbuf_ofs = ofs - buf_ofs; 438 while (inbuf_ofs < buf_len) { 439 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) { 440 printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n", 441 empty_start, ofs); 442 DIRTY_SPACE(ofs-empty_start); 443 goto scan_more; 444 } 445 446 inbuf_ofs+=4; 447 ofs += 4; 448 } 449 /* Ran off end. */ 450 D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs)); 451 452 /* If we're only checking the beginning of a block with a cleanmarker, 453 bail now */ 454 if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && 455 c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_phys) { 456 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size))); 457 return BLK_STATE_CLEANMARKER; 458 } 459 460 /* See how much more there is to read in this eraseblock... */ 461 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 462 if (!buf_len) { 463 /* No more to read. Break out of main loop without marking 464 this range of empty space as dirty (because it's not) */ 465 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n", 466 empty_start)); 467 break; 468 } 469 D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs)); 470 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 471 if (err) 472 return err; 473 buf_ofs = ofs; 474 goto more_empty; 475 } 476 477 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) { 478 printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs); 479 DIRTY_SPACE(4); 480 ofs += 4; 481 continue; 482 } 483 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) { 484 D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs)); 485 DIRTY_SPACE(4); 486 ofs += 4; 487 continue; 488 } 489 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) { 490 printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs); 491 printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n"); 492 DIRTY_SPACE(4); 493 ofs += 4; 494 continue; 495 } 496 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) { 497 /* OK. We're out of possibilities. Whinge and move on */ 498 noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", 499 JFFS2_MAGIC_BITMASK, ofs, 500 je16_to_cpu(node->magic)); 501 DIRTY_SPACE(4); 502 ofs += 4; 503 continue; 504 } 505 /* We seem to have a node of sorts. Check the CRC */ 506 crcnode.magic = node->magic; 507 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE); 508 crcnode.totlen = node->totlen; 509 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4); 510 511 if (hdr_crc != je32_to_cpu(node->hdr_crc)) { 512 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", 513 ofs, je16_to_cpu(node->magic), 514 je16_to_cpu(node->nodetype), 515 je32_to_cpu(node->totlen), 516 je32_to_cpu(node->hdr_crc), 517 hdr_crc); 518 DIRTY_SPACE(4); 519 ofs += 4; 520 continue; 521 } 522 523 if (ofs + je32_to_cpu(node->totlen) > 524 jeb->offset + c->sector_size) { 525 /* Eep. Node goes over the end of the erase block. */ 526 printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n", 527 ofs, je32_to_cpu(node->totlen)); 528 printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n"); 529 DIRTY_SPACE(4); 530 ofs += 4; 531 continue; 532 } 533 534 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) { 535 /* Wheee. This is an obsoleted node */ 536 D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs)); 537 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 538 ofs += PAD(je32_to_cpu(node->totlen)); 539 continue; 540 } 541 542 switch(je16_to_cpu(node->nodetype)) { 543 case JFFS2_NODETYPE_INODE: 544 if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) { 545 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 546 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n", 547 sizeof(struct jffs2_raw_inode), buf_len, ofs)); 548 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 549 if (err) 550 return err; 551 buf_ofs = ofs; 552 node = (void *)buf; 553 } 554 err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs); 555 if (err) return err; 556 ofs += PAD(je32_to_cpu(node->totlen)); 557 break; 558 559 case JFFS2_NODETYPE_DIRENT: 560 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { 561 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 562 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n", 563 je32_to_cpu(node->totlen), buf_len, ofs)); 564 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 565 if (err) 566 return err; 567 buf_ofs = ofs; 568 node = (void *)buf; 569 } 570 err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs); 571 if (err) return err; 572 ofs += PAD(je32_to_cpu(node->totlen)); 573 break; 574 575 case JFFS2_NODETYPE_CLEANMARKER: 576 D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs)); 577 if (je32_to_cpu(node->totlen) != c->cleanmarker_size) { 578 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 579 ofs, je32_to_cpu(node->totlen), c->cleanmarker_size); 580 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 581 ofs += PAD(sizeof(struct jffs2_unknown_node)); 582 } else if (jeb->first_node) { 583 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset); 584 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 585 ofs += PAD(sizeof(struct jffs2_unknown_node)); 586 } else { 587 struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref(); 588 if (!marker_ref) { 589 printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n"); 590 return -ENOMEM; 591 } 592 marker_ref->next_in_ino = NULL; 593 marker_ref->next_phys = NULL; 594 marker_ref->flash_offset = ofs | REF_NORMAL; 595 marker_ref->__totlen = c->cleanmarker_size; 596 jeb->first_node = jeb->last_node = marker_ref; 597 598 USED_SPACE(PAD(c->cleanmarker_size)); 599 ofs += PAD(c->cleanmarker_size); 600 } 601 break; 602 603 case JFFS2_NODETYPE_PADDING: 604 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 605 ofs += PAD(je32_to_cpu(node->totlen)); 606 break; 607 608 default: 609 switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) { 610 case JFFS2_FEATURE_ROCOMPAT: 611 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 612 c->flags |= JFFS2_SB_FLAG_RO; 613 if (!(jffs2_is_readonly(c))) 614 return -EROFS; 615 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 616 ofs += PAD(je32_to_cpu(node->totlen)); 617 break; 618 619 case JFFS2_FEATURE_INCOMPAT: 620 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 621 return -EINVAL; 622 623 case JFFS2_FEATURE_RWCOMPAT_DELETE: 624 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 625 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 626 ofs += PAD(je32_to_cpu(node->totlen)); 627 break; 628 629 case JFFS2_FEATURE_RWCOMPAT_COPY: 630 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 631 USED_SPACE(PAD(je32_to_cpu(node->totlen))); 632 ofs += PAD(je32_to_cpu(node->totlen)); 633 break; 634 } 635 } 636 } 637 638 639 D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 640 jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size)); 641 642 /* mark_node_obsolete can add to wasted !! */ 643 if (jeb->wasted_size) { 644 jeb->dirty_size += jeb->wasted_size; 645 c->dirty_size += jeb->wasted_size; 646 c->wasted_size -= jeb->wasted_size; 647 jeb->wasted_size = 0; 648 } 649 650 if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size 651 && (!jeb->first_node || !jeb->first_node->next_phys) ) 652 return BLK_STATE_CLEANMARKER; 653 654 /* move blocks with max 4 byte dirty space to cleanlist */ 655 else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) { 656 c->dirty_size -= jeb->dirty_size; 657 c->wasted_size += jeb->dirty_size; 658 jeb->wasted_size += jeb->dirty_size; 659 jeb->dirty_size = 0; 660 return BLK_STATE_CLEAN; 661 } else if (jeb->used_size || jeb->unchecked_size) 662 return BLK_STATE_PARTDIRTY; 663 else 664 return BLK_STATE_ALLDIRTY; 665 } 666 667 static struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino) 668 { 669 struct jffs2_inode_cache *ic; 670 671 ic = jffs2_get_ino_cache(c, ino); 672 if (ic) 673 return ic; 674 675 if (ino > c->highest_ino) 676 c->highest_ino = ino; 677 678 ic = jffs2_alloc_inode_cache(); 679 if (!ic) { 680 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n"); 681 return NULL; 682 } 683 memset(ic, 0, sizeof(*ic)); 684 685 ic->ino = ino; 686 ic->nodes = (void *)ic; 687 jffs2_add_ino_cache(c, ic); 688 if (ino == 1) 689 ic->nlink = 1; 690 return ic; 691 } 692 693 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 694 struct jffs2_raw_inode *ri, uint32_t ofs) 695 { 696 struct jffs2_raw_node_ref *raw; 697 struct jffs2_inode_cache *ic; 698 uint32_t ino = je32_to_cpu(ri->ino); 699 700 D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs)); 701 702 /* We do very little here now. Just check the ino# to which we should attribute 703 this node; we can do all the CRC checking etc. later. There's a tradeoff here -- 704 we used to scan the flash once only, reading everything we want from it into 705 memory, then building all our in-core data structures and freeing the extra 706 information. Now we allow the first part of the mount to complete a lot quicker, 707 but we have to go _back_ to the flash in order to finish the CRC checking, etc. 708 Which means that the _full_ amount of time to get to proper write mode with GC 709 operational may actually be _longer_ than before. Sucks to be me. */ 710 711 raw = jffs2_alloc_raw_node_ref(); 712 if (!raw) { 713 printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n"); 714 return -ENOMEM; 715 } 716 717 ic = jffs2_get_ino_cache(c, ino); 718 if (!ic) { 719 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the 720 first node we found for this inode. Do a CRC check to protect against the former 721 case */ 722 uint32_t crc = crc32(0, ri, sizeof(*ri)-8); 723 724 if (crc != je32_to_cpu(ri->node_crc)) { 725 printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 726 ofs, je32_to_cpu(ri->node_crc), crc); 727 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 728 DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen))); 729 jffs2_free_raw_node_ref(raw); 730 return 0; 731 } 732 ic = jffs2_scan_make_ino_cache(c, ino); 733 if (!ic) { 734 jffs2_free_raw_node_ref(raw); 735 return -ENOMEM; 736 } 737 } 738 739 /* Wheee. It worked */ 740 741 raw->flash_offset = ofs | REF_UNCHECKED; 742 raw->__totlen = PAD(je32_to_cpu(ri->totlen)); 743 raw->next_phys = NULL; 744 raw->next_in_ino = ic->nodes; 745 746 ic->nodes = raw; 747 if (!jeb->first_node) 748 jeb->first_node = raw; 749 if (jeb->last_node) 750 jeb->last_node->next_phys = raw; 751 jeb->last_node = raw; 752 753 D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n", 754 je32_to_cpu(ri->ino), je32_to_cpu(ri->version), 755 je32_to_cpu(ri->offset), 756 je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize))); 757 758 pseudo_random += je32_to_cpu(ri->version); 759 760 UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen))); 761 return 0; 762 } 763 764 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 765 struct jffs2_raw_dirent *rd, uint32_t ofs) 766 { 767 struct jffs2_raw_node_ref *raw; 768 struct jffs2_full_dirent *fd; 769 struct jffs2_inode_cache *ic; 770 uint32_t crc; 771 772 D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs)); 773 774 /* We don't get here unless the node is still valid, so we don't have to 775 mask in the ACCURATE bit any more. */ 776 crc = crc32(0, rd, sizeof(*rd)-8); 777 778 if (crc != je32_to_cpu(rd->node_crc)) { 779 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 780 ofs, je32_to_cpu(rd->node_crc), crc); 781 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 782 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 783 return 0; 784 } 785 786 pseudo_random += je32_to_cpu(rd->version); 787 788 fd = jffs2_alloc_full_dirent(rd->nsize+1); 789 if (!fd) { 790 return -ENOMEM; 791 } 792 memcpy(&fd->name, rd->name, rd->nsize); 793 fd->name[rd->nsize] = 0; 794 795 crc = crc32(0, fd->name, rd->nsize); 796 if (crc != je32_to_cpu(rd->name_crc)) { 797 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 798 ofs, je32_to_cpu(rd->name_crc), crc); 799 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino))); 800 jffs2_free_full_dirent(fd); 801 /* FIXME: Why do we believe totlen? */ 802 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */ 803 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 804 return 0; 805 } 806 raw = jffs2_alloc_raw_node_ref(); 807 if (!raw) { 808 jffs2_free_full_dirent(fd); 809 printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n"); 810 return -ENOMEM; 811 } 812 ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino)); 813 if (!ic) { 814 jffs2_free_full_dirent(fd); 815 jffs2_free_raw_node_ref(raw); 816 return -ENOMEM; 817 } 818 819 raw->__totlen = PAD(je32_to_cpu(rd->totlen)); 820 raw->flash_offset = ofs | REF_PRISTINE; 821 raw->next_phys = NULL; 822 raw->next_in_ino = ic->nodes; 823 ic->nodes = raw; 824 if (!jeb->first_node) 825 jeb->first_node = raw; 826 if (jeb->last_node) 827 jeb->last_node->next_phys = raw; 828 jeb->last_node = raw; 829 830 fd->raw = raw; 831 fd->next = NULL; 832 fd->version = je32_to_cpu(rd->version); 833 fd->ino = je32_to_cpu(rd->ino); 834 fd->nhash = full_name_hash(fd->name, rd->nsize); 835 fd->type = rd->type; 836 USED_SPACE(PAD(je32_to_cpu(rd->totlen))); 837 jffs2_add_fd_to_list(c, fd, &ic->scan_dents); 838 839 return 0; 840 } 841 842 static int count_list(struct list_head *l) 843 { 844 uint32_t count = 0; 845 struct list_head *tmp; 846 847 list_for_each(tmp, l) { 848 count++; 849 } 850 return count; 851 } 852 853 /* Note: This breaks if list_empty(head). I don't care. You 854 might, if you copy this code and use it elsewhere :) */ 855 static void rotate_list(struct list_head *head, uint32_t count) 856 { 857 struct list_head *n = head->next; 858 859 list_del(head); 860 while(count--) { 861 n = n->next; 862 } 863 list_add(head, n); 864 } 865 866 void jffs2_rotate_lists(struct jffs2_sb_info *c) 867 { 868 uint32_t x; 869 uint32_t rotateby; 870 871 x = count_list(&c->clean_list); 872 if (x) { 873 rotateby = pseudo_random % x; 874 D1(printk(KERN_DEBUG "Rotating clean_list by %d\n", rotateby)); 875 876 rotate_list((&c->clean_list), rotateby); 877 878 D1(printk(KERN_DEBUG "Erase block at front of clean_list is at %08x\n", 879 list_entry(c->clean_list.next, struct jffs2_eraseblock, list)->offset)); 880 } else { 881 D1(printk(KERN_DEBUG "Not rotating empty clean_list\n")); 882 } 883 884 x = count_list(&c->very_dirty_list); 885 if (x) { 886 rotateby = pseudo_random % x; 887 D1(printk(KERN_DEBUG "Rotating very_dirty_list by %d\n", rotateby)); 888 889 rotate_list((&c->very_dirty_list), rotateby); 890 891 D1(printk(KERN_DEBUG "Erase block at front of very_dirty_list is at %08x\n", 892 list_entry(c->very_dirty_list.next, struct jffs2_eraseblock, list)->offset)); 893 } else { 894 D1(printk(KERN_DEBUG "Not rotating empty very_dirty_list\n")); 895 } 896 897 x = count_list(&c->dirty_list); 898 if (x) { 899 rotateby = pseudo_random % x; 900 D1(printk(KERN_DEBUG "Rotating dirty_list by %d\n", rotateby)); 901 902 rotate_list((&c->dirty_list), rotateby); 903 904 D1(printk(KERN_DEBUG "Erase block at front of dirty_list is at %08x\n", 905 list_entry(c->dirty_list.next, struct jffs2_eraseblock, list)->offset)); 906 } else { 907 D1(printk(KERN_DEBUG "Not rotating empty dirty_list\n")); 908 } 909 910 x = count_list(&c->erasable_list); 911 if (x) { 912 rotateby = pseudo_random % x; 913 D1(printk(KERN_DEBUG "Rotating erasable_list by %d\n", rotateby)); 914 915 rotate_list((&c->erasable_list), rotateby); 916 917 D1(printk(KERN_DEBUG "Erase block at front of erasable_list is at %08x\n", 918 list_entry(c->erasable_list.next, struct jffs2_eraseblock, list)->offset)); 919 } else { 920 D1(printk(KERN_DEBUG "Not rotating empty erasable_list\n")); 921 } 922 923 if (c->nr_erasing_blocks) { 924 rotateby = pseudo_random % c->nr_erasing_blocks; 925 D1(printk(KERN_DEBUG "Rotating erase_pending_list by %d\n", rotateby)); 926 927 rotate_list((&c->erase_pending_list), rotateby); 928 929 D1(printk(KERN_DEBUG "Erase block at front of erase_pending_list is at %08x\n", 930 list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list)->offset)); 931 } else { 932 D1(printk(KERN_DEBUG "Not rotating empty erase_pending_list\n")); 933 } 934 935 if (c->nr_free_blocks) { 936 rotateby = pseudo_random % c->nr_free_blocks; 937 D1(printk(KERN_DEBUG "Rotating free_list by %d\n", rotateby)); 938 939 rotate_list((&c->free_list), rotateby); 940 941 D1(printk(KERN_DEBUG "Erase block at front of free_list is at %08x\n", 942 list_entry(c->free_list.next, struct jffs2_eraseblock, list)->offset)); 943 } else { 944 D1(printk(KERN_DEBUG "Not rotating empty free_list\n")); 945 } 946 } 947