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 1.119 2005/02/17 17:51:13 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 22 #define DEFAULT_EMPTY_SCAN_SIZE 1024 23 24 #define DIRTY_SPACE(x) do { typeof(x) _x = (x); \ 25 c->free_size -= _x; c->dirty_size += _x; \ 26 jeb->free_size -= _x ; jeb->dirty_size += _x; \ 27 }while(0) 28 #define USED_SPACE(x) do { typeof(x) _x = (x); \ 29 c->free_size -= _x; c->used_size += _x; \ 30 jeb->free_size -= _x ; jeb->used_size += _x; \ 31 }while(0) 32 #define UNCHECKED_SPACE(x) do { typeof(x) _x = (x); \ 33 c->free_size -= _x; c->unchecked_size += _x; \ 34 jeb->free_size -= _x ; jeb->unchecked_size += _x; \ 35 }while(0) 36 37 #define noisy_printk(noise, args...) do { \ 38 if (*(noise)) { \ 39 printk(KERN_NOTICE args); \ 40 (*(noise))--; \ 41 if (!(*(noise))) { \ 42 printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \ 43 } \ 44 } \ 45 } while(0) 46 47 static uint32_t pseudo_random; 48 49 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 50 unsigned char *buf, uint32_t buf_size); 51 52 /* These helper functions _must_ increase ofs and also do the dirty/used space accounting. 53 * Returning an error will abort the mount - bad checksums etc. should just mark the space 54 * as dirty. 55 */ 56 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 57 struct jffs2_raw_inode *ri, uint32_t ofs); 58 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 59 struct jffs2_raw_dirent *rd, uint32_t ofs); 60 61 #define BLK_STATE_ALLFF 0 62 #define BLK_STATE_CLEAN 1 63 #define BLK_STATE_PARTDIRTY 2 64 #define BLK_STATE_CLEANMARKER 3 65 #define BLK_STATE_ALLDIRTY 4 66 #define BLK_STATE_BADBLOCK 5 67 68 static inline int min_free(struct jffs2_sb_info *c) 69 { 70 uint32_t min = 2 * sizeof(struct jffs2_raw_inode); 71 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 72 if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize) 73 return c->wbuf_pagesize; 74 #endif 75 return min; 76 77 } 78 79 static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size) { 80 if (sector_size < DEFAULT_EMPTY_SCAN_SIZE) 81 return sector_size; 82 else 83 return DEFAULT_EMPTY_SCAN_SIZE; 84 } 85 86 int jffs2_scan_medium(struct jffs2_sb_info *c) 87 { 88 int i, ret; 89 uint32_t empty_blocks = 0, bad_blocks = 0; 90 unsigned char *flashbuf = NULL; 91 uint32_t buf_size = 0; 92 #ifndef __ECOS 93 size_t pointlen; 94 95 if (c->mtd->point) { 96 ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf); 97 if (!ret && pointlen < c->mtd->size) { 98 /* Don't muck about if it won't let us point to the whole flash */ 99 D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen)); 100 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 101 flashbuf = NULL; 102 } 103 if (ret) 104 D1(printk(KERN_DEBUG "MTD point failed %d\n", ret)); 105 } 106 #endif 107 if (!flashbuf) { 108 /* For NAND it's quicker to read a whole eraseblock at a time, 109 apparently */ 110 if (jffs2_cleanmarker_oob(c)) 111 buf_size = c->sector_size; 112 else 113 buf_size = PAGE_SIZE; 114 115 /* Respect kmalloc limitations */ 116 if (buf_size > 128*1024) 117 buf_size = 128*1024; 118 119 D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size)); 120 flashbuf = kmalloc(buf_size, GFP_KERNEL); 121 if (!flashbuf) 122 return -ENOMEM; 123 } 124 125 for (i=0; i<c->nr_blocks; i++) { 126 struct jffs2_eraseblock *jeb = &c->blocks[i]; 127 128 ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset), buf_size); 129 130 if (ret < 0) 131 goto out; 132 133 ACCT_PARANOIA_CHECK(jeb); 134 135 /* Now decide which list to put it on */ 136 switch(ret) { 137 case BLK_STATE_ALLFF: 138 /* 139 * Empty block. Since we can't be sure it 140 * was entirely erased, we just queue it for erase 141 * again. It will be marked as such when the erase 142 * is complete. Meanwhile we still count it as empty 143 * for later checks. 144 */ 145 empty_blocks++; 146 list_add(&jeb->list, &c->erase_pending_list); 147 c->nr_erasing_blocks++; 148 break; 149 150 case BLK_STATE_CLEANMARKER: 151 /* Only a CLEANMARKER node is valid */ 152 if (!jeb->dirty_size) { 153 /* It's actually free */ 154 list_add(&jeb->list, &c->free_list); 155 c->nr_free_blocks++; 156 } else { 157 /* Dirt */ 158 D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset)); 159 list_add(&jeb->list, &c->erase_pending_list); 160 c->nr_erasing_blocks++; 161 } 162 break; 163 164 case BLK_STATE_CLEAN: 165 /* Full (or almost full) of clean data. Clean list */ 166 list_add(&jeb->list, &c->clean_list); 167 break; 168 169 case BLK_STATE_PARTDIRTY: 170 /* Some data, but not full. Dirty list. */ 171 /* We want to remember the block with most free space 172 and stick it in the 'nextblock' position to start writing to it. */ 173 if (jeb->free_size > min_free(c) && 174 (!c->nextblock || c->nextblock->free_size < jeb->free_size)) { 175 /* Better candidate for the next writes to go to */ 176 if (c->nextblock) { 177 c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; 178 c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size; 179 c->free_size -= c->nextblock->free_size; 180 c->wasted_size -= c->nextblock->wasted_size; 181 c->nextblock->free_size = c->nextblock->wasted_size = 0; 182 if (VERYDIRTY(c, c->nextblock->dirty_size)) { 183 list_add(&c->nextblock->list, &c->very_dirty_list); 184 } else { 185 list_add(&c->nextblock->list, &c->dirty_list); 186 } 187 } 188 c->nextblock = jeb; 189 } else { 190 jeb->dirty_size += jeb->free_size + jeb->wasted_size; 191 c->dirty_size += jeb->free_size + jeb->wasted_size; 192 c->free_size -= jeb->free_size; 193 c->wasted_size -= jeb->wasted_size; 194 jeb->free_size = jeb->wasted_size = 0; 195 if (VERYDIRTY(c, jeb->dirty_size)) { 196 list_add(&jeb->list, &c->very_dirty_list); 197 } else { 198 list_add(&jeb->list, &c->dirty_list); 199 } 200 } 201 break; 202 203 case BLK_STATE_ALLDIRTY: 204 /* Nothing valid - not even a clean marker. Needs erasing. */ 205 /* For now we just put it on the erasing list. We'll start the erases later */ 206 D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset)); 207 list_add(&jeb->list, &c->erase_pending_list); 208 c->nr_erasing_blocks++; 209 break; 210 211 case BLK_STATE_BADBLOCK: 212 D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset)); 213 list_add(&jeb->list, &c->bad_list); 214 c->bad_size += c->sector_size; 215 c->free_size -= c->sector_size; 216 bad_blocks++; 217 break; 218 default: 219 printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n"); 220 BUG(); 221 } 222 } 223 224 /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */ 225 if (c->nextblock && (c->nextblock->dirty_size)) { 226 c->nextblock->wasted_size += c->nextblock->dirty_size; 227 c->wasted_size += c->nextblock->dirty_size; 228 c->dirty_size -= c->nextblock->dirty_size; 229 c->nextblock->dirty_size = 0; 230 } 231 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 232 if (!jffs2_can_mark_obsolete(c) && c->nextblock && (c->nextblock->free_size & (c->wbuf_pagesize-1))) { 233 /* If we're going to start writing into a block which already 234 contains data, and the end of the data isn't page-aligned, 235 skip a little and align it. */ 236 237 uint32_t skip = c->nextblock->free_size & (c->wbuf_pagesize-1); 238 239 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n", 240 skip)); 241 c->nextblock->wasted_size += skip; 242 c->wasted_size += skip; 243 244 c->nextblock->free_size -= skip; 245 c->free_size -= skip; 246 } 247 #endif 248 if (c->nr_erasing_blocks) { 249 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) { 250 printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n"); 251 printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks); 252 ret = -EIO; 253 goto out; 254 } 255 jffs2_erase_pending_trigger(c); 256 } 257 ret = 0; 258 out: 259 if (buf_size) 260 kfree(flashbuf); 261 #ifndef __ECOS 262 else 263 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size); 264 #endif 265 return ret; 266 } 267 268 static int jffs2_fill_scan_buf (struct jffs2_sb_info *c, unsigned char *buf, 269 uint32_t ofs, uint32_t len) 270 { 271 int ret; 272 size_t retlen; 273 274 ret = jffs2_flash_read(c, ofs, len, &retlen, buf); 275 if (ret) { 276 D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret)); 277 return ret; 278 } 279 if (retlen < len) { 280 D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen)); 281 return -EIO; 282 } 283 D2(printk(KERN_DEBUG "Read 0x%x bytes from 0x%08x into buf\n", len, ofs)); 284 D2(printk(KERN_DEBUG "000: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n", 285 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])); 286 return 0; 287 } 288 289 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 290 unsigned char *buf, uint32_t buf_size) { 291 struct jffs2_unknown_node *node; 292 struct jffs2_unknown_node crcnode; 293 uint32_t ofs, prevofs; 294 uint32_t hdr_crc, buf_ofs, buf_len; 295 int err; 296 int noise = 0; 297 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 298 int cleanmarkerfound = 0; 299 #endif 300 301 ofs = jeb->offset; 302 prevofs = jeb->offset - 1; 303 304 D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs)); 305 306 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 307 if (jffs2_cleanmarker_oob(c)) { 308 int ret = jffs2_check_nand_cleanmarker(c, jeb); 309 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret)); 310 /* Even if it's not found, we still scan to see 311 if the block is empty. We use this information 312 to decide whether to erase it or not. */ 313 switch (ret) { 314 case 0: cleanmarkerfound = 1; break; 315 case 1: break; 316 case 2: return BLK_STATE_BADBLOCK; 317 case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */ 318 default: return ret; 319 } 320 } 321 #endif 322 buf_ofs = jeb->offset; 323 324 if (!buf_size) { 325 buf_len = c->sector_size; 326 } else { 327 buf_len = EMPTY_SCAN_SIZE(c->sector_size); 328 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len); 329 if (err) 330 return err; 331 } 332 333 /* We temporarily use 'ofs' as a pointer into the buffer/jeb */ 334 ofs = 0; 335 336 /* Scan only 4KiB of 0xFF before declaring it's empty */ 337 while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF) 338 ofs += 4; 339 340 if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) { 341 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 342 if (jffs2_cleanmarker_oob(c)) { 343 /* scan oob, take care of cleanmarker */ 344 int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound); 345 D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret)); 346 switch (ret) { 347 case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF; 348 case 1: return BLK_STATE_ALLDIRTY; 349 default: return ret; 350 } 351 } 352 #endif 353 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset)); 354 if (c->cleanmarker_size == 0) 355 return BLK_STATE_CLEANMARKER; /* don't bother with re-erase */ 356 else 357 return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */ 358 } 359 if (ofs) { 360 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset, 361 jeb->offset + ofs)); 362 DIRTY_SPACE(ofs); 363 } 364 365 /* Now ofs is a complete physical flash offset as it always was... */ 366 ofs += jeb->offset; 367 368 noise = 10; 369 370 scan_more: 371 while(ofs < jeb->offset + c->sector_size) { 372 373 D1(ACCT_PARANOIA_CHECK(jeb)); 374 375 cond_resched(); 376 377 if (ofs & 3) { 378 printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs); 379 ofs = PAD(ofs); 380 continue; 381 } 382 if (ofs == prevofs) { 383 printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs); 384 DIRTY_SPACE(4); 385 ofs += 4; 386 continue; 387 } 388 prevofs = ofs; 389 390 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) { 391 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), 392 jeb->offset, c->sector_size, ofs, sizeof(*node))); 393 DIRTY_SPACE((jeb->offset + c->sector_size)-ofs); 394 break; 395 } 396 397 if (buf_ofs + buf_len < ofs + sizeof(*node)) { 398 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 399 D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n", 400 sizeof(struct jffs2_unknown_node), buf_len, ofs)); 401 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 402 if (err) 403 return err; 404 buf_ofs = ofs; 405 } 406 407 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs]; 408 409 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) { 410 uint32_t inbuf_ofs; 411 uint32_t empty_start; 412 413 empty_start = ofs; 414 ofs += 4; 415 416 D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs)); 417 more_empty: 418 inbuf_ofs = ofs - buf_ofs; 419 while (inbuf_ofs < buf_len) { 420 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) { 421 printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n", 422 empty_start, ofs); 423 DIRTY_SPACE(ofs-empty_start); 424 goto scan_more; 425 } 426 427 inbuf_ofs+=4; 428 ofs += 4; 429 } 430 /* Ran off end. */ 431 D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs)); 432 433 /* If we're only checking the beginning of a block with a cleanmarker, 434 bail now */ 435 if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) && 436 c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_phys) { 437 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size))); 438 return BLK_STATE_CLEANMARKER; 439 } 440 441 /* See how much more there is to read in this eraseblock... */ 442 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 443 if (!buf_len) { 444 /* No more to read. Break out of main loop without marking 445 this range of empty space as dirty (because it's not) */ 446 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n", 447 empty_start)); 448 break; 449 } 450 D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs)); 451 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 452 if (err) 453 return err; 454 buf_ofs = ofs; 455 goto more_empty; 456 } 457 458 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) { 459 printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs); 460 DIRTY_SPACE(4); 461 ofs += 4; 462 continue; 463 } 464 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) { 465 D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs)); 466 DIRTY_SPACE(4); 467 ofs += 4; 468 continue; 469 } 470 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) { 471 printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs); 472 printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n"); 473 DIRTY_SPACE(4); 474 ofs += 4; 475 continue; 476 } 477 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) { 478 /* OK. We're out of possibilities. Whinge and move on */ 479 noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", 480 JFFS2_MAGIC_BITMASK, ofs, 481 je16_to_cpu(node->magic)); 482 DIRTY_SPACE(4); 483 ofs += 4; 484 continue; 485 } 486 /* We seem to have a node of sorts. Check the CRC */ 487 crcnode.magic = node->magic; 488 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE); 489 crcnode.totlen = node->totlen; 490 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4); 491 492 if (hdr_crc != je32_to_cpu(node->hdr_crc)) { 493 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", 494 ofs, je16_to_cpu(node->magic), 495 je16_to_cpu(node->nodetype), 496 je32_to_cpu(node->totlen), 497 je32_to_cpu(node->hdr_crc), 498 hdr_crc); 499 DIRTY_SPACE(4); 500 ofs += 4; 501 continue; 502 } 503 504 if (ofs + je32_to_cpu(node->totlen) > 505 jeb->offset + c->sector_size) { 506 /* Eep. Node goes over the end of the erase block. */ 507 printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n", 508 ofs, je32_to_cpu(node->totlen)); 509 printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n"); 510 DIRTY_SPACE(4); 511 ofs += 4; 512 continue; 513 } 514 515 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) { 516 /* Wheee. This is an obsoleted node */ 517 D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs)); 518 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 519 ofs += PAD(je32_to_cpu(node->totlen)); 520 continue; 521 } 522 523 switch(je16_to_cpu(node->nodetype)) { 524 case JFFS2_NODETYPE_INODE: 525 if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) { 526 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 527 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n", 528 sizeof(struct jffs2_raw_inode), buf_len, ofs)); 529 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 530 if (err) 531 return err; 532 buf_ofs = ofs; 533 node = (void *)buf; 534 } 535 err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs); 536 if (err) return err; 537 ofs += PAD(je32_to_cpu(node->totlen)); 538 break; 539 540 case JFFS2_NODETYPE_DIRENT: 541 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) { 542 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs); 543 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n", 544 je32_to_cpu(node->totlen), buf_len, ofs)); 545 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len); 546 if (err) 547 return err; 548 buf_ofs = ofs; 549 node = (void *)buf; 550 } 551 err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs); 552 if (err) return err; 553 ofs += PAD(je32_to_cpu(node->totlen)); 554 break; 555 556 case JFFS2_NODETYPE_CLEANMARKER: 557 D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs)); 558 if (je32_to_cpu(node->totlen) != c->cleanmarker_size) { 559 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n", 560 ofs, je32_to_cpu(node->totlen), c->cleanmarker_size); 561 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 562 ofs += PAD(sizeof(struct jffs2_unknown_node)); 563 } else if (jeb->first_node) { 564 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset); 565 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node))); 566 ofs += PAD(sizeof(struct jffs2_unknown_node)); 567 } else { 568 struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref(); 569 if (!marker_ref) { 570 printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n"); 571 return -ENOMEM; 572 } 573 marker_ref->next_in_ino = NULL; 574 marker_ref->next_phys = NULL; 575 marker_ref->flash_offset = ofs | REF_NORMAL; 576 marker_ref->__totlen = c->cleanmarker_size; 577 jeb->first_node = jeb->last_node = marker_ref; 578 579 USED_SPACE(PAD(c->cleanmarker_size)); 580 ofs += PAD(c->cleanmarker_size); 581 } 582 break; 583 584 case JFFS2_NODETYPE_PADDING: 585 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 586 ofs += PAD(je32_to_cpu(node->totlen)); 587 break; 588 589 default: 590 switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) { 591 case JFFS2_FEATURE_ROCOMPAT: 592 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 593 c->flags |= JFFS2_SB_FLAG_RO; 594 if (!(jffs2_is_readonly(c))) 595 return -EROFS; 596 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 597 ofs += PAD(je32_to_cpu(node->totlen)); 598 break; 599 600 case JFFS2_FEATURE_INCOMPAT: 601 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs); 602 return -EINVAL; 603 604 case JFFS2_FEATURE_RWCOMPAT_DELETE: 605 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 606 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen))); 607 ofs += PAD(je32_to_cpu(node->totlen)); 608 break; 609 610 case JFFS2_FEATURE_RWCOMPAT_COPY: 611 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs)); 612 USED_SPACE(PAD(je32_to_cpu(node->totlen))); 613 ofs += PAD(je32_to_cpu(node->totlen)); 614 break; 615 } 616 } 617 } 618 619 620 D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset, 621 jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size)); 622 623 /* mark_node_obsolete can add to wasted !! */ 624 if (jeb->wasted_size) { 625 jeb->dirty_size += jeb->wasted_size; 626 c->dirty_size += jeb->wasted_size; 627 c->wasted_size -= jeb->wasted_size; 628 jeb->wasted_size = 0; 629 } 630 631 if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size 632 && (!jeb->first_node || !jeb->first_node->next_phys) ) 633 return BLK_STATE_CLEANMARKER; 634 635 /* move blocks with max 4 byte dirty space to cleanlist */ 636 else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) { 637 c->dirty_size -= jeb->dirty_size; 638 c->wasted_size += jeb->dirty_size; 639 jeb->wasted_size += jeb->dirty_size; 640 jeb->dirty_size = 0; 641 return BLK_STATE_CLEAN; 642 } else if (jeb->used_size || jeb->unchecked_size) 643 return BLK_STATE_PARTDIRTY; 644 else 645 return BLK_STATE_ALLDIRTY; 646 } 647 648 static struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino) 649 { 650 struct jffs2_inode_cache *ic; 651 652 ic = jffs2_get_ino_cache(c, ino); 653 if (ic) 654 return ic; 655 656 if (ino > c->highest_ino) 657 c->highest_ino = ino; 658 659 ic = jffs2_alloc_inode_cache(); 660 if (!ic) { 661 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n"); 662 return NULL; 663 } 664 memset(ic, 0, sizeof(*ic)); 665 666 ic->ino = ino; 667 ic->nodes = (void *)ic; 668 jffs2_add_ino_cache(c, ic); 669 if (ino == 1) 670 ic->nlink = 1; 671 return ic; 672 } 673 674 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 675 struct jffs2_raw_inode *ri, uint32_t ofs) 676 { 677 struct jffs2_raw_node_ref *raw; 678 struct jffs2_inode_cache *ic; 679 uint32_t ino = je32_to_cpu(ri->ino); 680 681 D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs)); 682 683 /* We do very little here now. Just check the ino# to which we should attribute 684 this node; we can do all the CRC checking etc. later. There's a tradeoff here -- 685 we used to scan the flash once only, reading everything we want from it into 686 memory, then building all our in-core data structures and freeing the extra 687 information. Now we allow the first part of the mount to complete a lot quicker, 688 but we have to go _back_ to the flash in order to finish the CRC checking, etc. 689 Which means that the _full_ amount of time to get to proper write mode with GC 690 operational may actually be _longer_ than before. Sucks to be me. */ 691 692 raw = jffs2_alloc_raw_node_ref(); 693 if (!raw) { 694 printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n"); 695 return -ENOMEM; 696 } 697 698 ic = jffs2_get_ino_cache(c, ino); 699 if (!ic) { 700 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the 701 first node we found for this inode. Do a CRC check to protect against the former 702 case */ 703 uint32_t crc = crc32(0, ri, sizeof(*ri)-8); 704 705 if (crc != je32_to_cpu(ri->node_crc)) { 706 printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 707 ofs, je32_to_cpu(ri->node_crc), crc); 708 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 709 DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen))); 710 jffs2_free_raw_node_ref(raw); 711 return 0; 712 } 713 ic = jffs2_scan_make_ino_cache(c, ino); 714 if (!ic) { 715 jffs2_free_raw_node_ref(raw); 716 return -ENOMEM; 717 } 718 } 719 720 /* Wheee. It worked */ 721 722 raw->flash_offset = ofs | REF_UNCHECKED; 723 raw->__totlen = PAD(je32_to_cpu(ri->totlen)); 724 raw->next_phys = NULL; 725 raw->next_in_ino = ic->nodes; 726 727 ic->nodes = raw; 728 if (!jeb->first_node) 729 jeb->first_node = raw; 730 if (jeb->last_node) 731 jeb->last_node->next_phys = raw; 732 jeb->last_node = raw; 733 734 D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n", 735 je32_to_cpu(ri->ino), je32_to_cpu(ri->version), 736 je32_to_cpu(ri->offset), 737 je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize))); 738 739 pseudo_random += je32_to_cpu(ri->version); 740 741 UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen))); 742 return 0; 743 } 744 745 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, 746 struct jffs2_raw_dirent *rd, uint32_t ofs) 747 { 748 struct jffs2_raw_node_ref *raw; 749 struct jffs2_full_dirent *fd; 750 struct jffs2_inode_cache *ic; 751 uint32_t crc; 752 753 D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs)); 754 755 /* We don't get here unless the node is still valid, so we don't have to 756 mask in the ACCURATE bit any more. */ 757 crc = crc32(0, rd, sizeof(*rd)-8); 758 759 if (crc != je32_to_cpu(rd->node_crc)) { 760 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 761 ofs, je32_to_cpu(rd->node_crc), crc); 762 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */ 763 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 764 return 0; 765 } 766 767 pseudo_random += je32_to_cpu(rd->version); 768 769 fd = jffs2_alloc_full_dirent(rd->nsize+1); 770 if (!fd) { 771 return -ENOMEM; 772 } 773 memcpy(&fd->name, rd->name, rd->nsize); 774 fd->name[rd->nsize] = 0; 775 776 crc = crc32(0, fd->name, rd->nsize); 777 if (crc != je32_to_cpu(rd->name_crc)) { 778 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", 779 ofs, je32_to_cpu(rd->name_crc), crc); 780 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino))); 781 jffs2_free_full_dirent(fd); 782 /* FIXME: Why do we believe totlen? */ 783 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */ 784 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen))); 785 return 0; 786 } 787 raw = jffs2_alloc_raw_node_ref(); 788 if (!raw) { 789 jffs2_free_full_dirent(fd); 790 printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n"); 791 return -ENOMEM; 792 } 793 ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino)); 794 if (!ic) { 795 jffs2_free_full_dirent(fd); 796 jffs2_free_raw_node_ref(raw); 797 return -ENOMEM; 798 } 799 800 raw->__totlen = PAD(je32_to_cpu(rd->totlen)); 801 raw->flash_offset = ofs | REF_PRISTINE; 802 raw->next_phys = NULL; 803 raw->next_in_ino = ic->nodes; 804 ic->nodes = raw; 805 if (!jeb->first_node) 806 jeb->first_node = raw; 807 if (jeb->last_node) 808 jeb->last_node->next_phys = raw; 809 jeb->last_node = raw; 810 811 fd->raw = raw; 812 fd->next = NULL; 813 fd->version = je32_to_cpu(rd->version); 814 fd->ino = je32_to_cpu(rd->ino); 815 fd->nhash = full_name_hash(fd->name, rd->nsize); 816 fd->type = rd->type; 817 USED_SPACE(PAD(je32_to_cpu(rd->totlen))); 818 jffs2_add_fd_to_list(c, fd, &ic->scan_dents); 819 820 return 0; 821 } 822 823 static int count_list(struct list_head *l) 824 { 825 uint32_t count = 0; 826 struct list_head *tmp; 827 828 list_for_each(tmp, l) { 829 count++; 830 } 831 return count; 832 } 833 834 /* Note: This breaks if list_empty(head). I don't care. You 835 might, if you copy this code and use it elsewhere :) */ 836 static void rotate_list(struct list_head *head, uint32_t count) 837 { 838 struct list_head *n = head->next; 839 840 list_del(head); 841 while(count--) { 842 n = n->next; 843 } 844 list_add(head, n); 845 } 846 847 void jffs2_rotate_lists(struct jffs2_sb_info *c) 848 { 849 uint32_t x; 850 uint32_t rotateby; 851 852 x = count_list(&c->clean_list); 853 if (x) { 854 rotateby = pseudo_random % x; 855 D1(printk(KERN_DEBUG "Rotating clean_list by %d\n", rotateby)); 856 857 rotate_list((&c->clean_list), rotateby); 858 859 D1(printk(KERN_DEBUG "Erase block at front of clean_list is at %08x\n", 860 list_entry(c->clean_list.next, struct jffs2_eraseblock, list)->offset)); 861 } else { 862 D1(printk(KERN_DEBUG "Not rotating empty clean_list\n")); 863 } 864 865 x = count_list(&c->very_dirty_list); 866 if (x) { 867 rotateby = pseudo_random % x; 868 D1(printk(KERN_DEBUG "Rotating very_dirty_list by %d\n", rotateby)); 869 870 rotate_list((&c->very_dirty_list), rotateby); 871 872 D1(printk(KERN_DEBUG "Erase block at front of very_dirty_list is at %08x\n", 873 list_entry(c->very_dirty_list.next, struct jffs2_eraseblock, list)->offset)); 874 } else { 875 D1(printk(KERN_DEBUG "Not rotating empty very_dirty_list\n")); 876 } 877 878 x = count_list(&c->dirty_list); 879 if (x) { 880 rotateby = pseudo_random % x; 881 D1(printk(KERN_DEBUG "Rotating dirty_list by %d\n", rotateby)); 882 883 rotate_list((&c->dirty_list), rotateby); 884 885 D1(printk(KERN_DEBUG "Erase block at front of dirty_list is at %08x\n", 886 list_entry(c->dirty_list.next, struct jffs2_eraseblock, list)->offset)); 887 } else { 888 D1(printk(KERN_DEBUG "Not rotating empty dirty_list\n")); 889 } 890 891 x = count_list(&c->erasable_list); 892 if (x) { 893 rotateby = pseudo_random % x; 894 D1(printk(KERN_DEBUG "Rotating erasable_list by %d\n", rotateby)); 895 896 rotate_list((&c->erasable_list), rotateby); 897 898 D1(printk(KERN_DEBUG "Erase block at front of erasable_list is at %08x\n", 899 list_entry(c->erasable_list.next, struct jffs2_eraseblock, list)->offset)); 900 } else { 901 D1(printk(KERN_DEBUG "Not rotating empty erasable_list\n")); 902 } 903 904 if (c->nr_erasing_blocks) { 905 rotateby = pseudo_random % c->nr_erasing_blocks; 906 D1(printk(KERN_DEBUG "Rotating erase_pending_list by %d\n", rotateby)); 907 908 rotate_list((&c->erase_pending_list), rotateby); 909 910 D1(printk(KERN_DEBUG "Erase block at front of erase_pending_list is at %08x\n", 911 list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list)->offset)); 912 } else { 913 D1(printk(KERN_DEBUG "Not rotating empty erase_pending_list\n")); 914 } 915 916 if (c->nr_free_blocks) { 917 rotateby = pseudo_random % c->nr_free_blocks; 918 D1(printk(KERN_DEBUG "Rotating free_list by %d\n", rotateby)); 919 920 rotate_list((&c->free_list), rotateby); 921 922 D1(printk(KERN_DEBUG "Erase block at front of free_list is at %08x\n", 923 list_entry(c->free_list.next, struct jffs2_eraseblock, list)->offset)); 924 } else { 925 D1(printk(KERN_DEBUG "Not rotating empty free_list\n")); 926 } 927 } 928