| 1 | /* |
| 2 | * YAFFS: Yet Another Flash File System. A NAND-flash specific file system. |
| 3 | * |
| 4 | * Copyright (C) 2002-2010 Aleph One Ltd. |
| 5 | * for Toby Churchill Ltd and Brightstar Engineering |
| 6 | * |
| 7 | * Created by Charles Manning <charles@aleph1.co.uk> |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License version 2 as |
| 11 | * published by the Free Software Foundation. |
| 12 | */ |
| 13 | #include "yaffs_yaffs1.h" |
| 14 | #include "yportenv.h" |
| 15 | #include "yaffs_trace.h" |
| 16 | #include "yaffs_bitmap.h" |
| 17 | #include "yaffs_getblockinfo.h" |
| 18 | #include "yaffs_nand.h" |
| 19 | |
| 20 | |
| 21 | int yaffs1_scan(yaffs_dev_t *dev) |
| 22 | { |
| 23 | yaffs_ext_tags tags; |
| 24 | int blk; |
| 25 | int blockIterator; |
| 26 | int startIterator; |
| 27 | int endIterator; |
| 28 | int result; |
| 29 | |
| 30 | int chunk; |
| 31 | int c; |
| 32 | int deleted; |
| 33 | yaffs_block_state_t state; |
| 34 | yaffs_obj_t *hard_list = NULL; |
| 35 | yaffs_block_info_t *bi; |
| 36 | __u32 seq_number; |
| 37 | yaffs_obj_header *oh; |
| 38 | yaffs_obj_t *in; |
| 39 | yaffs_obj_t *parent; |
| 40 | |
| 41 | int alloc_failed = 0; |
| 42 | |
| 43 | struct yaffs_shadow_fixer_s *shadowFixerList = NULL; |
| 44 | |
| 45 | |
| 46 | __u8 *chunkData; |
| 47 | |
| 48 | |
| 49 | |
| 50 | T(YAFFS_TRACE_SCAN, |
| 51 | (TSTR("yaffs1_scan starts intstartblk %d intendblk %d..." TENDSTR), |
| 52 | dev->internal_start_block, dev->internal_end_block)); |
| 53 | |
| 54 | chunkData = yaffs_get_temp_buffer(dev, __LINE__); |
| 55 | |
| 56 | dev->seq_number = YAFFS_LOWEST_SEQUENCE_NUMBER; |
| 57 | |
| 58 | /* Scan all the blocks to determine their state */ |
| 59 | bi = dev->block_info; |
| 60 | for (blk = dev->internal_start_block; blk <= dev->internal_end_block; blk++) { |
| 61 | yaffs_clear_chunk_bits(dev, blk); |
| 62 | bi->pages_in_use = 0; |
| 63 | bi->soft_del_pages = 0; |
| 64 | |
| 65 | yaffs_query_init_block_state(dev, blk, &state, &seq_number); |
| 66 | |
| 67 | bi->block_state = state; |
| 68 | bi->seq_number = seq_number; |
| 69 | |
| 70 | if (bi->seq_number == YAFFS_SEQUENCE_BAD_BLOCK) |
| 71 | bi->block_state = state = YAFFS_BLOCK_STATE_DEAD; |
| 72 | |
| 73 | T(YAFFS_TRACE_SCAN_DEBUG, |
| 74 | (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk, |
| 75 | state, seq_number)); |
| 76 | |
| 77 | if (state == YAFFS_BLOCK_STATE_DEAD) { |
| 78 | T(YAFFS_TRACE_BAD_BLOCKS, |
| 79 | (TSTR("block %d is bad" TENDSTR), blk)); |
| 80 | } else if (state == YAFFS_BLOCK_STATE_EMPTY) { |
| 81 | T(YAFFS_TRACE_SCAN_DEBUG, |
| 82 | (TSTR("Block empty " TENDSTR))); |
| 83 | dev->n_erased_blocks++; |
| 84 | dev->n_free_chunks += dev->param.chunks_per_block; |
| 85 | } |
| 86 | bi++; |
| 87 | } |
| 88 | |
| 89 | startIterator = dev->internal_start_block; |
| 90 | endIterator = dev->internal_end_block; |
| 91 | |
| 92 | /* For each block.... */ |
| 93 | for (blockIterator = startIterator; !alloc_failed && blockIterator <= endIterator; |
| 94 | blockIterator++) { |
| 95 | |
| 96 | YYIELD(); |
| 97 | |
| 98 | YYIELD(); |
| 99 | |
| 100 | blk = blockIterator; |
| 101 | |
| 102 | bi = yaffs_get_block_info(dev, blk); |
| 103 | state = bi->block_state; |
| 104 | |
| 105 | deleted = 0; |
| 106 | |
| 107 | /* For each chunk in each block that needs scanning....*/ |
| 108 | for (c = 0; !alloc_failed && c < dev->param.chunks_per_block && |
| 109 | state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) { |
| 110 | /* Read the tags and decide what to do */ |
| 111 | chunk = blk * dev->param.chunks_per_block + c; |
| 112 | |
| 113 | result = yaffs_rd_chunk_tags_nand(dev, chunk, NULL, |
| 114 | &tags); |
| 115 | |
| 116 | /* Let's have a good look at this chunk... */ |
| 117 | |
| 118 | if (tags.ecc_result == YAFFS_ECC_RESULT_UNFIXED || tags.is_deleted) { |
| 119 | /* YAFFS1 only... |
| 120 | * A deleted chunk |
| 121 | */ |
| 122 | deleted++; |
| 123 | dev->n_free_chunks++; |
| 124 | /*T((" %d %d deleted\n",blk,c)); */ |
| 125 | } else if (!tags.chunk_used) { |
| 126 | /* An unassigned chunk in the block |
| 127 | * This means that either the block is empty or |
| 128 | * this is the one being allocated from |
| 129 | */ |
| 130 | |
| 131 | if (c == 0) { |
| 132 | /* We're looking at the first chunk in the block so the block is unused */ |
| 133 | state = YAFFS_BLOCK_STATE_EMPTY; |
| 134 | dev->n_erased_blocks++; |
| 135 | } else { |
| 136 | /* this is the block being allocated from */ |
| 137 | T(YAFFS_TRACE_SCAN, |
| 138 | (TSTR |
| 139 | (" Allocating from %d %d" TENDSTR), |
| 140 | blk, c)); |
| 141 | state = YAFFS_BLOCK_STATE_ALLOCATING; |
| 142 | dev->alloc_block = blk; |
| 143 | dev->alloc_page = c; |
| 144 | dev->alloc_block_finder = blk; |
| 145 | /* Set block finder here to encourage the allocator to go forth from here. */ |
| 146 | |
| 147 | } |
| 148 | |
| 149 | dev->n_free_chunks += (dev->param.chunks_per_block - c); |
| 150 | } else if (tags.chunk_id > 0) { |
| 151 | /* chunk_id > 0 so it is a data chunk... */ |
| 152 | unsigned int endpos; |
| 153 | |
| 154 | yaffs_set_chunk_bit(dev, blk, c); |
| 155 | bi->pages_in_use++; |
| 156 | |
| 157 | in = yaffs_find_or_create_by_number(dev, |
| 158 | tags. |
| 159 | obj_id, |
| 160 | YAFFS_OBJECT_TYPE_FILE); |
| 161 | /* PutChunkIntoFile checks for a clash (two data chunks with |
| 162 | * the same chunk_id). |
| 163 | */ |
| 164 | |
| 165 | if (!in) |
| 166 | alloc_failed = 1; |
| 167 | |
| 168 | if (in) { |
| 169 | if (!yaffs_put_chunk_in_file(in, tags.chunk_id, chunk, 1)) |
| 170 | alloc_failed = 1; |
| 171 | } |
| 172 | |
| 173 | endpos = |
| 174 | (tags.chunk_id - 1) * dev->data_bytes_per_chunk + |
| 175 | tags.n_bytes; |
| 176 | if (in && |
| 177 | in->variant_type == YAFFS_OBJECT_TYPE_FILE |
| 178 | && in->variant.file_variant.scanned_size < |
| 179 | endpos) { |
| 180 | in->variant.file_variant. |
| 181 | scanned_size = endpos; |
| 182 | if (!dev->param.use_header_file_size) { |
| 183 | in->variant.file_variant. |
| 184 | file_size = |
| 185 | in->variant.file_variant. |
| 186 | scanned_size; |
| 187 | } |
| 188 | |
| 189 | } |
| 190 | /* T((" %d %d data %d %d\n",blk,c,tags.obj_id,tags.chunk_id)); */ |
| 191 | } else { |
| 192 | /* chunk_id == 0, so it is an ObjectHeader. |
| 193 | * Thus, we read in the object header and make the object |
| 194 | */ |
| 195 | yaffs_set_chunk_bit(dev, blk, c); |
| 196 | bi->pages_in_use++; |
| 197 | |
| 198 | result = yaffs_rd_chunk_tags_nand(dev, chunk, |
| 199 | chunkData, |
| 200 | NULL); |
| 201 | |
| 202 | oh = (yaffs_obj_header *) chunkData; |
| 203 | |
| 204 | in = yaffs_find_by_number(dev, |
| 205 | tags.obj_id); |
| 206 | if (in && in->variant_type != oh->type) { |
| 207 | /* This should not happen, but somehow |
| 208 | * Wev'e ended up with an obj_id that has been reused but not yet |
| 209 | * deleted, and worse still it has changed type. Delete the old object. |
| 210 | */ |
| 211 | |
| 212 | yaffs_del_obj(in); |
| 213 | |
| 214 | in = 0; |
| 215 | } |
| 216 | |
| 217 | in = yaffs_find_or_create_by_number(dev, |
| 218 | tags. |
| 219 | obj_id, |
| 220 | oh->type); |
| 221 | |
| 222 | if (!in) |
| 223 | alloc_failed = 1; |
| 224 | |
| 225 | if (in && oh->shadows_obj > 0) { |
| 226 | |
| 227 | struct yaffs_shadow_fixer_s *fixer; |
| 228 | fixer = YMALLOC(sizeof(struct yaffs_shadow_fixer_s)); |
| 229 | if (fixer) { |
| 230 | fixer->next = shadowFixerList; |
| 231 | shadowFixerList = fixer; |
| 232 | fixer->obj_id = tags.obj_id; |
| 233 | fixer->shadowed_id = oh->shadows_obj; |
| 234 | T(YAFFS_TRACE_SCAN, |
| 235 | (TSTR |
| 236 | (" Shadow fixer: %d shadows %d" TENDSTR), |
| 237 | fixer->obj_id, fixer->shadowed_id)); |
| 238 | |
| 239 | } |
| 240 | |
| 241 | } |
| 242 | |
| 243 | if (in && in->valid) { |
| 244 | /* We have already filled this one. We have a duplicate and need to resolve it. */ |
| 245 | |
| 246 | unsigned existingSerial = in->serial; |
| 247 | unsigned newSerial = tags.serial_number; |
| 248 | |
| 249 | if (((existingSerial + 1) & 3) == newSerial) { |
| 250 | /* Use new one - destroy the exisiting one */ |
| 251 | yaffs_chunk_del(dev, |
| 252 | in->hdr_chunk, |
| 253 | 1, __LINE__); |
| 254 | in->valid = 0; |
| 255 | } else { |
| 256 | /* Use existing - destroy this one. */ |
| 257 | yaffs_chunk_del(dev, chunk, 1, |
| 258 | __LINE__); |
| 259 | } |
| 260 | } |
| 261 | |
| 262 | if (in && !in->valid && |
| 263 | (tags.obj_id == YAFFS_OBJECTID_ROOT || |
| 264 | tags.obj_id == YAFFS_OBJECTID_LOSTNFOUND)) { |
| 265 | /* We only load some info, don't fiddle with directory structure */ |
| 266 | in->valid = 1; |
| 267 | in->variant_type = oh->type; |
| 268 | |
| 269 | in->yst_mode = oh->yst_mode; |
| 270 | #ifdef CONFIG_YAFFS_WINCE |
| 271 | in->win_atime[0] = oh->win_atime[0]; |
| 272 | in->win_ctime[0] = oh->win_ctime[0]; |
| 273 | in->win_mtime[0] = oh->win_mtime[0]; |
| 274 | in->win_atime[1] = oh->win_atime[1]; |
| 275 | in->win_ctime[1] = oh->win_ctime[1]; |
| 276 | in->win_mtime[1] = oh->win_mtime[1]; |
| 277 | #else |
| 278 | in->yst_uid = oh->yst_uid; |
| 279 | in->yst_gid = oh->yst_gid; |
| 280 | in->yst_atime = oh->yst_atime; |
| 281 | in->yst_mtime = oh->yst_mtime; |
| 282 | in->yst_ctime = oh->yst_ctime; |
| 283 | in->yst_rdev = oh->yst_rdev; |
| 284 | #endif |
| 285 | in->hdr_chunk = chunk; |
| 286 | in->serial = tags.serial_number; |
| 287 | |
| 288 | } else if (in && !in->valid) { |
| 289 | /* we need to load this info */ |
| 290 | |
| 291 | in->valid = 1; |
| 292 | in->variant_type = oh->type; |
| 293 | |
| 294 | in->yst_mode = oh->yst_mode; |
| 295 | #ifdef CONFIG_YAFFS_WINCE |
| 296 | in->win_atime[0] = oh->win_atime[0]; |
| 297 | in->win_ctime[0] = oh->win_ctime[0]; |
| 298 | in->win_mtime[0] = oh->win_mtime[0]; |
| 299 | in->win_atime[1] = oh->win_atime[1]; |
| 300 | in->win_ctime[1] = oh->win_ctime[1]; |
| 301 | in->win_mtime[1] = oh->win_mtime[1]; |
| 302 | #else |
| 303 | in->yst_uid = oh->yst_uid; |
| 304 | in->yst_gid = oh->yst_gid; |
| 305 | in->yst_atime = oh->yst_atime; |
| 306 | in->yst_mtime = oh->yst_mtime; |
| 307 | in->yst_ctime = oh->yst_ctime; |
| 308 | in->yst_rdev = oh->yst_rdev; |
| 309 | #endif |
| 310 | in->hdr_chunk = chunk; |
| 311 | in->serial = tags.serial_number; |
| 312 | |
| 313 | yaffs_set_obj_name_from_oh(in, oh); |
| 314 | in->dirty = 0; |
| 315 | |
| 316 | /* directory stuff... |
| 317 | * hook up to parent |
| 318 | */ |
| 319 | |
| 320 | parent = |
| 321 | yaffs_find_or_create_by_number |
| 322 | (dev, oh->parent_obj_id, |
| 323 | YAFFS_OBJECT_TYPE_DIRECTORY); |
| 324 | if (!parent) |
| 325 | alloc_failed = 1; |
| 326 | if (parent && parent->variant_type == |
| 327 | YAFFS_OBJECT_TYPE_UNKNOWN) { |
| 328 | /* Set up as a directory */ |
| 329 | parent->variant_type = |
| 330 | YAFFS_OBJECT_TYPE_DIRECTORY; |
| 331 | YINIT_LIST_HEAD(&parent->variant. |
| 332 | dir_variant. |
| 333 | children); |
| 334 | } else if (!parent || parent->variant_type != |
| 335 | YAFFS_OBJECT_TYPE_DIRECTORY) { |
| 336 | /* Hoosterman, another problem.... |
| 337 | * We're trying to use a non-directory as a directory |
| 338 | */ |
| 339 | |
| 340 | T(YAFFS_TRACE_ERROR, |
| 341 | (TSTR |
| 342 | ("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found." |
| 343 | TENDSTR))); |
| 344 | parent = dev->lost_n_found; |
| 345 | } |
| 346 | |
| 347 | yaffs_add_obj_to_dir(parent, in); |
| 348 | |
| 349 | if (0 && (parent == dev->del_dir || |
| 350 | parent == dev->unlinked_dir)) { |
| 351 | in->deleted = 1; /* If it is unlinked at start up then it wants deleting */ |
| 352 | dev->n_deleted_files++; |
| 353 | } |
| 354 | /* Note re hardlinks. |
| 355 | * Since we might scan a hardlink before its equivalent object is scanned |
| 356 | * we put them all in a list. |
| 357 | * After scanning is complete, we should have all the objects, so we run through this |
| 358 | * list and fix up all the chains. |
| 359 | */ |
| 360 | |
| 361 | switch (in->variant_type) { |
| 362 | case YAFFS_OBJECT_TYPE_UNKNOWN: |
| 363 | /* Todo got a problem */ |
| 364 | break; |
| 365 | case YAFFS_OBJECT_TYPE_FILE: |
| 366 | if (dev->param.use_header_file_size) |
| 367 | |
| 368 | in->variant.file_variant. |
| 369 | file_size = |
| 370 | oh->file_size; |
| 371 | |
| 372 | break; |
| 373 | case YAFFS_OBJECT_TYPE_HARDLINK: |
| 374 | in->variant.hardlink_variant. |
| 375 | equiv_id = |
| 376 | oh->equiv_id; |
| 377 | in->hard_links.next = |
| 378 | (struct ylist_head *) |
| 379 | hard_list; |
| 380 | hard_list = in; |
| 381 | break; |
| 382 | case YAFFS_OBJECT_TYPE_DIRECTORY: |
| 383 | /* Do nothing */ |
| 384 | break; |
| 385 | case YAFFS_OBJECT_TYPE_SPECIAL: |
| 386 | /* Do nothing */ |
| 387 | break; |
| 388 | case YAFFS_OBJECT_TYPE_SYMLINK: |
| 389 | in->variant.symlink_variant.alias = |
| 390 | yaffs_clone_str(oh->alias); |
| 391 | if (!in->variant.symlink_variant.alias) |
| 392 | alloc_failed = 1; |
| 393 | break; |
| 394 | } |
| 395 | |
| 396 | } |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) { |
| 401 | /* If we got this far while scanning, then the block is fully allocated.*/ |
| 402 | state = YAFFS_BLOCK_STATE_FULL; |
| 403 | } |
| 404 | |
| 405 | if (state == YAFFS_BLOCK_STATE_ALLOCATING) { |
| 406 | /* If the block was partially allocated then treat it as fully allocated.*/ |
| 407 | state = YAFFS_BLOCK_STATE_FULL; |
| 408 | dev->alloc_block = -1; |
| 409 | } |
| 410 | |
| 411 | bi->block_state = state; |
| 412 | |
| 413 | /* Now let's see if it was dirty */ |
| 414 | if (bi->pages_in_use == 0 && |
| 415 | !bi->has_shrink_hdr && |
| 416 | bi->block_state == YAFFS_BLOCK_STATE_FULL) { |
| 417 | yaffs_block_became_dirty(dev, blk); |
| 418 | } |
| 419 | |
| 420 | } |
| 421 | |
| 422 | |
| 423 | /* Ok, we've done all the scanning. |
| 424 | * Fix up the hard link chains. |
| 425 | * We should now have scanned all the objects, now it's time to add these |
| 426 | * hardlinks. |
| 427 | */ |
| 428 | |
| 429 | yaffs_link_fixup(dev, hard_list); |
| 430 | |
| 431 | /* Fix up any shadowed objects */ |
| 432 | { |
| 433 | struct yaffs_shadow_fixer_s *fixer; |
| 434 | yaffs_obj_t *obj; |
| 435 | |
| 436 | while (shadowFixerList) { |
| 437 | fixer = shadowFixerList; |
| 438 | shadowFixerList = fixer->next; |
| 439 | /* Complete the rename transaction by deleting the shadowed object |
| 440 | * then setting the object header to unshadowed. |
| 441 | */ |
| 442 | obj = yaffs_find_by_number(dev, fixer->shadowed_id); |
| 443 | if (obj) |
| 444 | yaffs_del_obj(obj); |
| 445 | |
| 446 | obj = yaffs_find_by_number(dev, fixer->obj_id); |
| 447 | |
| 448 | if (obj) |
| 449 | yaffs_update_oh(obj, NULL, 1, 0, 0, NULL); |
| 450 | |
| 451 | YFREE(fixer); |
| 452 | } |
| 453 | } |
| 454 | |
| 455 | yaffs_release_temp_buffer(dev, chunkData, __LINE__); |
| 456 | |
| 457 | if (alloc_failed) |
| 458 | return YAFFS_FAIL; |
| 459 | |
| 460 | T(YAFFS_TRACE_SCAN, (TSTR("yaffs1_scan ends" TENDSTR))); |
| 461 | |
| 462 | |
| 463 | return YAFFS_OK; |
| 464 | } |
| 465 | |
| 466 | |
