1 /* 2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system. 3 * 4 * Copyright (C) 2002-2011 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 14 #include "yaffs_guts.h" 15 #include "yaffs_trace.h" 16 #include "yaffs_yaffs2.h" 17 #include "yaffs_checkptrw.h" 18 #include "yaffs_bitmap.h" 19 #include "yaffs_nand.h" 20 #include "yaffs_getblockinfo.h" 21 #include "yaffs_verify.h" 22 #include "yaffs_attribs.h" 23 #include "yaffs_summary.h" 24 25 /* 26 * Checkpoints are really no benefit on very small partitions. 27 * 28 * To save space on small partitions don't bother with checkpoints unless 29 * the partition is at least this big. 30 */ 31 #define YAFFS_CHECKPOINT_MIN_BLOCKS 60 32 #define YAFFS_SMALL_HOLE_THRESHOLD 4 33 34 /* 35 * Oldest Dirty Sequence Number handling. 36 */ 37 38 /* yaffs_calc_oldest_dirty_seq() 39 * yaffs2_find_oldest_dirty_seq() 40 * Calculate the oldest dirty sequence number if we don't know it. 41 */ 42 void yaffs_calc_oldest_dirty_seq(struct yaffs_dev *dev) 43 { 44 int i; 45 unsigned seq; 46 unsigned block_no = 0; 47 struct yaffs_block_info *b; 48 49 if (!dev->param.is_yaffs2) 50 return; 51 52 /* Find the oldest dirty sequence number. */ 53 seq = dev->seq_number + 1; 54 b = dev->block_info; 55 for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) { 56 if (b->block_state == YAFFS_BLOCK_STATE_FULL && 57 (b->pages_in_use - b->soft_del_pages) < 58 dev->param.chunks_per_block && 59 b->seq_number < seq) { 60 seq = b->seq_number; 61 block_no = i; 62 } 63 b++; 64 } 65 66 if (block_no) { 67 dev->oldest_dirty_seq = seq; 68 dev->oldest_dirty_block = block_no; 69 } 70 } 71 72 void yaffs2_find_oldest_dirty_seq(struct yaffs_dev *dev) 73 { 74 if (!dev->param.is_yaffs2) 75 return; 76 77 if (!dev->oldest_dirty_seq) 78 yaffs_calc_oldest_dirty_seq(dev); 79 } 80 81 /* 82 * yaffs_clear_oldest_dirty_seq() 83 * Called when a block is erased or marked bad. (ie. when its seq_number 84 * becomes invalid). If the value matches the oldest then we clear 85 * dev->oldest_dirty_seq to force its recomputation. 86 */ 87 void yaffs2_clear_oldest_dirty_seq(struct yaffs_dev *dev, 88 struct yaffs_block_info *bi) 89 { 90 91 if (!dev->param.is_yaffs2) 92 return; 93 94 if (!bi || bi->seq_number == dev->oldest_dirty_seq) { 95 dev->oldest_dirty_seq = 0; 96 dev->oldest_dirty_block = 0; 97 } 98 } 99 100 /* 101 * yaffs2_update_oldest_dirty_seq() 102 * Update the oldest dirty sequence number whenever we dirty a block. 103 * Only do this if the oldest_dirty_seq is actually being tracked. 104 */ 105 void yaffs2_update_oldest_dirty_seq(struct yaffs_dev *dev, unsigned block_no, 106 struct yaffs_block_info *bi) 107 { 108 if (!dev->param.is_yaffs2) 109 return; 110 111 if (dev->oldest_dirty_seq) { 112 if (dev->oldest_dirty_seq > bi->seq_number) { 113 dev->oldest_dirty_seq = bi->seq_number; 114 dev->oldest_dirty_block = block_no; 115 } 116 } 117 } 118 119 int yaffs_block_ok_for_gc(struct yaffs_dev *dev, struct yaffs_block_info *bi) 120 { 121 122 if (!dev->param.is_yaffs2) 123 return 1; /* disqualification only applies to yaffs2. */ 124 125 if (!bi->has_shrink_hdr) 126 return 1; /* can gc */ 127 128 yaffs2_find_oldest_dirty_seq(dev); 129 130 /* Can't do gc of this block if there are any blocks older than this 131 * one that have discarded pages. 132 */ 133 return (bi->seq_number <= dev->oldest_dirty_seq); 134 } 135 136 /* 137 * yaffs2_find_refresh_block() 138 * periodically finds the oldest full block by sequence number for refreshing. 139 * Only for yaffs2. 140 */ 141 u32 yaffs2_find_refresh_block(struct yaffs_dev *dev) 142 { 143 u32 b; 144 u32 oldest = 0; 145 u32 oldest_seq = 0; 146 struct yaffs_block_info *bi; 147 148 if (!dev->param.is_yaffs2) 149 return oldest; 150 151 /* 152 * If refresh period < 10 then refreshing is disabled. 153 */ 154 if (dev->param.refresh_period < 10) 155 return oldest; 156 157 /* 158 * Fix broken values. 159 */ 160 if (dev->refresh_skip > dev->param.refresh_period) 161 dev->refresh_skip = dev->param.refresh_period; 162 163 if (dev->refresh_skip > 0) 164 return oldest; 165 166 /* 167 * Refresh skip is now zero. 168 * We'll do a refresh this time around.... 169 * Update the refresh skip and find the oldest block. 170 */ 171 dev->refresh_skip = dev->param.refresh_period; 172 dev->refresh_count++; 173 bi = dev->block_info; 174 for (b = dev->internal_start_block; b <= dev->internal_end_block; b++) { 175 176 if (bi->block_state == YAFFS_BLOCK_STATE_FULL) { 177 178 if (oldest < 1 || bi->seq_number < oldest_seq) { 179 oldest = b; 180 oldest_seq = bi->seq_number; 181 } 182 } 183 bi++; 184 } 185 186 if (oldest > 0) { 187 yaffs_trace(YAFFS_TRACE_GC, 188 "GC refresh count %d selected block %d with seq_number %d", 189 dev->refresh_count, oldest, oldest_seq); 190 } 191 192 return oldest; 193 } 194 195 int yaffs2_checkpt_required(struct yaffs_dev *dev) 196 { 197 int nblocks; 198 199 if (!dev->param.is_yaffs2) 200 return 0; 201 202 nblocks = dev->internal_end_block - dev->internal_start_block + 1; 203 204 return !dev->param.skip_checkpt_wr && 205 !dev->read_only && (nblocks >= YAFFS_CHECKPOINT_MIN_BLOCKS); 206 } 207 208 int yaffs_calc_checkpt_blocks_required(struct yaffs_dev *dev) 209 { 210 int retval; 211 int n_bytes = 0; 212 int n_blocks; 213 int dev_blocks; 214 215 if (!dev->param.is_yaffs2) 216 return 0; 217 218 if (!dev->checkpoint_blocks_required && yaffs2_checkpt_required(dev)) { 219 /* Not a valid value so recalculate */ 220 dev_blocks = dev->param.end_block - dev->param.start_block + 1; 221 n_bytes += sizeof(struct yaffs_checkpt_validity); 222 n_bytes += sizeof(struct yaffs_checkpt_dev); 223 n_bytes += dev_blocks * sizeof(struct yaffs_block_info); 224 n_bytes += dev_blocks * dev->chunk_bit_stride; 225 n_bytes += 226 (sizeof(struct yaffs_checkpt_obj) + sizeof(u32)) * 227 dev->n_obj; 228 n_bytes += (dev->tnode_size + sizeof(u32)) * dev->n_tnodes; 229 n_bytes += sizeof(struct yaffs_checkpt_validity); 230 n_bytes += sizeof(u32); /* checksum */ 231 232 /* Round up and add 2 blocks to allow for some bad blocks, 233 * so add 3 */ 234 235 n_blocks = 236 (n_bytes / 237 (dev->data_bytes_per_chunk * 238 dev->param.chunks_per_block)) + 3; 239 240 dev->checkpoint_blocks_required = n_blocks; 241 } 242 243 retval = dev->checkpoint_blocks_required - dev->blocks_in_checkpt; 244 if (retval < 0) 245 retval = 0; 246 return retval; 247 } 248 249 /*--------------------- Checkpointing --------------------*/ 250 251 static int yaffs2_wr_checkpt_validity_marker(struct yaffs_dev *dev, int head) 252 { 253 struct yaffs_checkpt_validity cp; 254 255 memset(&cp, 0, sizeof(cp)); 256 257 cp.struct_type = sizeof(cp); 258 cp.magic = YAFFS_MAGIC; 259 cp.version = YAFFS_CHECKPOINT_VERSION; 260 cp.head = (head) ? 1 : 0; 261 262 return (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp)) ? 1 : 0; 263 } 264 265 static int yaffs2_rd_checkpt_validity_marker(struct yaffs_dev *dev, int head) 266 { 267 struct yaffs_checkpt_validity cp; 268 int ok; 269 270 ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp)); 271 272 if (ok) 273 ok = (cp.struct_type == sizeof(cp)) && 274 (cp.magic == YAFFS_MAGIC) && 275 (cp.version == YAFFS_CHECKPOINT_VERSION) && 276 (cp.head == ((head) ? 1 : 0)); 277 return ok ? 1 : 0; 278 } 279 280 static void yaffs2_dev_to_checkpt_dev(struct yaffs_checkpt_dev *cp, 281 struct yaffs_dev *dev) 282 { 283 cp->n_erased_blocks = dev->n_erased_blocks; 284 cp->alloc_block = dev->alloc_block; 285 cp->alloc_page = dev->alloc_page; 286 cp->n_free_chunks = dev->n_free_chunks; 287 288 cp->n_deleted_files = dev->n_deleted_files; 289 cp->n_unlinked_files = dev->n_unlinked_files; 290 cp->n_bg_deletions = dev->n_bg_deletions; 291 cp->seq_number = dev->seq_number; 292 293 } 294 295 static void yaffs_checkpt_dev_to_dev(struct yaffs_dev *dev, 296 struct yaffs_checkpt_dev *cp) 297 { 298 dev->n_erased_blocks = cp->n_erased_blocks; 299 dev->alloc_block = cp->alloc_block; 300 dev->alloc_page = cp->alloc_page; 301 dev->n_free_chunks = cp->n_free_chunks; 302 303 dev->n_deleted_files = cp->n_deleted_files; 304 dev->n_unlinked_files = cp->n_unlinked_files; 305 dev->n_bg_deletions = cp->n_bg_deletions; 306 dev->seq_number = cp->seq_number; 307 } 308 309 static int yaffs2_wr_checkpt_dev(struct yaffs_dev *dev) 310 { 311 struct yaffs_checkpt_dev cp; 312 u32 n_bytes; 313 u32 n_blocks = dev->internal_end_block - dev->internal_start_block + 1; 314 int ok; 315 316 /* Write device runtime values */ 317 yaffs2_dev_to_checkpt_dev(&cp, dev); 318 cp.struct_type = sizeof(cp); 319 320 ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp)); 321 if (!ok) 322 return 0; 323 324 /* Write block info */ 325 n_bytes = n_blocks * sizeof(struct yaffs_block_info); 326 ok = (yaffs2_checkpt_wr(dev, dev->block_info, n_bytes) == n_bytes); 327 if (!ok) 328 return 0; 329 330 /* Write chunk bits */ 331 n_bytes = n_blocks * dev->chunk_bit_stride; 332 ok = (yaffs2_checkpt_wr(dev, dev->chunk_bits, n_bytes) == n_bytes); 333 334 return ok ? 1 : 0; 335 } 336 337 static int yaffs2_rd_checkpt_dev(struct yaffs_dev *dev) 338 { 339 struct yaffs_checkpt_dev cp; 340 u32 n_bytes; 341 u32 n_blocks = 342 (dev->internal_end_block - dev->internal_start_block + 1); 343 int ok; 344 345 ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp)); 346 if (!ok) 347 return 0; 348 349 if (cp.struct_type != sizeof(cp)) 350 return 0; 351 352 yaffs_checkpt_dev_to_dev(dev, &cp); 353 354 n_bytes = n_blocks * sizeof(struct yaffs_block_info); 355 356 ok = (yaffs2_checkpt_rd(dev, dev->block_info, n_bytes) == n_bytes); 357 358 if (!ok) 359 return 0; 360 361 n_bytes = n_blocks * dev->chunk_bit_stride; 362 363 ok = (yaffs2_checkpt_rd(dev, dev->chunk_bits, n_bytes) == n_bytes); 364 365 return ok ? 1 : 0; 366 } 367 368 static void yaffs2_obj_checkpt_obj(struct yaffs_checkpt_obj *cp, 369 struct yaffs_obj *obj) 370 { 371 cp->obj_id = obj->obj_id; 372 cp->parent_id = (obj->parent) ? obj->parent->obj_id : 0; 373 cp->hdr_chunk = obj->hdr_chunk; 374 cp->variant_type = obj->variant_type; 375 cp->deleted = obj->deleted; 376 cp->soft_del = obj->soft_del; 377 cp->unlinked = obj->unlinked; 378 cp->fake = obj->fake; 379 cp->rename_allowed = obj->rename_allowed; 380 cp->unlink_allowed = obj->unlink_allowed; 381 cp->serial = obj->serial; 382 cp->n_data_chunks = obj->n_data_chunks; 383 384 if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) 385 cp->size_or_equiv_obj = obj->variant.file_variant.file_size; 386 else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) 387 cp->size_or_equiv_obj = obj->variant.hardlink_variant.equiv_id; 388 } 389 390 static int yaffs2_checkpt_obj_to_obj(struct yaffs_obj *obj, 391 struct yaffs_checkpt_obj *cp) 392 { 393 struct yaffs_obj *parent; 394 395 if (obj->variant_type != cp->variant_type) { 396 yaffs_trace(YAFFS_TRACE_ERROR, 397 "Checkpoint read object %d type %d chunk %d does not match existing object type %d", 398 cp->obj_id, cp->variant_type, cp->hdr_chunk, 399 obj->variant_type); 400 return 0; 401 } 402 403 obj->obj_id = cp->obj_id; 404 405 if (cp->parent_id) 406 parent = yaffs_find_or_create_by_number(obj->my_dev, 407 cp->parent_id, 408 YAFFS_OBJECT_TYPE_DIRECTORY); 409 else 410 parent = NULL; 411 412 if (parent) { 413 if (parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) { 414 yaffs_trace(YAFFS_TRACE_ALWAYS, 415 "Checkpoint read object %d parent %d type %d chunk %d Parent type, %d, not directory", 416 cp->obj_id, cp->parent_id, 417 cp->variant_type, cp->hdr_chunk, 418 parent->variant_type); 419 return 0; 420 } 421 yaffs_add_obj_to_dir(parent, obj); 422 } 423 424 obj->hdr_chunk = cp->hdr_chunk; 425 obj->variant_type = cp->variant_type; 426 obj->deleted = cp->deleted; 427 obj->soft_del = cp->soft_del; 428 obj->unlinked = cp->unlinked; 429 obj->fake = cp->fake; 430 obj->rename_allowed = cp->rename_allowed; 431 obj->unlink_allowed = cp->unlink_allowed; 432 obj->serial = cp->serial; 433 obj->n_data_chunks = cp->n_data_chunks; 434 435 if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE) 436 obj->variant.file_variant.file_size = cp->size_or_equiv_obj; 437 else if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) 438 obj->variant.hardlink_variant.equiv_id = cp->size_or_equiv_obj; 439 440 if (obj->hdr_chunk > 0) 441 obj->lazy_loaded = 1; 442 return 1; 443 } 444 445 static int yaffs2_checkpt_tnode_worker(struct yaffs_obj *in, 446 struct yaffs_tnode *tn, u32 level, 447 int chunk_offset) 448 { 449 int i; 450 struct yaffs_dev *dev = in->my_dev; 451 int ok = 1; 452 u32 base_offset; 453 454 if (!tn) 455 return 1; 456 457 if (level > 0) { 458 for (i = 0; i < YAFFS_NTNODES_INTERNAL && ok; i++) { 459 if (!tn->internal[i]) 460 continue; 461 ok = yaffs2_checkpt_tnode_worker(in, 462 tn->internal[i], 463 level - 1, 464 (chunk_offset << 465 YAFFS_TNODES_INTERNAL_BITS) + i); 466 } 467 return ok; 468 } 469 470 /* Level 0 tnode */ 471 base_offset = chunk_offset << YAFFS_TNODES_LEVEL0_BITS; 472 ok = (yaffs2_checkpt_wr(dev, &base_offset, sizeof(base_offset)) == 473 sizeof(base_offset)); 474 if (ok) 475 ok = (yaffs2_checkpt_wr(dev, tn, dev->tnode_size) == 476 dev->tnode_size); 477 478 return ok; 479 } 480 481 static int yaffs2_wr_checkpt_tnodes(struct yaffs_obj *obj) 482 { 483 u32 end_marker = ~0; 484 int ok = 1; 485 486 if (obj->variant_type != YAFFS_OBJECT_TYPE_FILE) 487 return ok; 488 489 ok = yaffs2_checkpt_tnode_worker(obj, 490 obj->variant.file_variant.top, 491 obj->variant.file_variant. 492 top_level, 0); 493 if (ok) 494 ok = (yaffs2_checkpt_wr(obj->my_dev, &end_marker, 495 sizeof(end_marker)) == sizeof(end_marker)); 496 497 return ok ? 1 : 0; 498 } 499 500 static int yaffs2_rd_checkpt_tnodes(struct yaffs_obj *obj) 501 { 502 u32 base_chunk; 503 int ok = 1; 504 struct yaffs_dev *dev = obj->my_dev; 505 struct yaffs_file_var *file_stuct_ptr = &obj->variant.file_variant; 506 struct yaffs_tnode *tn; 507 int nread = 0; 508 509 ok = (yaffs2_checkpt_rd(dev, &base_chunk, sizeof(base_chunk)) == 510 sizeof(base_chunk)); 511 512 while (ok && (~base_chunk)) { 513 nread++; 514 /* Read level 0 tnode */ 515 516 tn = yaffs_get_tnode(dev); 517 if (tn) 518 ok = (yaffs2_checkpt_rd(dev, tn, dev->tnode_size) == 519 dev->tnode_size); 520 else 521 ok = 0; 522 523 if (tn && ok) 524 ok = yaffs_add_find_tnode_0(dev, 525 file_stuct_ptr, 526 base_chunk, tn) ? 1 : 0; 527 528 if (ok) 529 ok = (yaffs2_checkpt_rd 530 (dev, &base_chunk, 531 sizeof(base_chunk)) == sizeof(base_chunk)); 532 } 533 534 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 535 "Checkpoint read tnodes %d records, last %d. ok %d", 536 nread, base_chunk, ok); 537 538 return ok ? 1 : 0; 539 } 540 541 static int yaffs2_wr_checkpt_objs(struct yaffs_dev *dev) 542 { 543 struct yaffs_obj *obj; 544 struct yaffs_checkpt_obj cp; 545 int i; 546 int ok = 1; 547 struct list_head *lh; 548 549 /* Iterate through the objects in each hash entry, 550 * dumping them to the checkpointing stream. 551 */ 552 553 for (i = 0; ok && i < YAFFS_NOBJECT_BUCKETS; i++) { 554 list_for_each(lh, &dev->obj_bucket[i].list) { 555 obj = list_entry(lh, struct yaffs_obj, hash_link); 556 if (!obj->defered_free) { 557 yaffs2_obj_checkpt_obj(&cp, obj); 558 cp.struct_type = sizeof(cp); 559 560 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 561 "Checkpoint write object %d parent %d type %d chunk %d obj addr %p", 562 cp.obj_id, cp.parent_id, 563 cp.variant_type, cp.hdr_chunk, obj); 564 565 ok = (yaffs2_checkpt_wr(dev, &cp, 566 sizeof(cp)) == sizeof(cp)); 567 568 if (ok && 569 obj->variant_type == 570 YAFFS_OBJECT_TYPE_FILE) 571 ok = yaffs2_wr_checkpt_tnodes(obj); 572 } 573 } 574 } 575 576 /* Dump end of list */ 577 memset(&cp, 0xff, sizeof(struct yaffs_checkpt_obj)); 578 cp.struct_type = sizeof(cp); 579 580 if (ok) 581 ok = (yaffs2_checkpt_wr(dev, &cp, sizeof(cp)) == sizeof(cp)); 582 583 return ok ? 1 : 0; 584 } 585 586 static int yaffs2_rd_checkpt_objs(struct yaffs_dev *dev) 587 { 588 struct yaffs_obj *obj; 589 struct yaffs_checkpt_obj cp; 590 int ok = 1; 591 int done = 0; 592 LIST_HEAD(hard_list); 593 594 595 while (ok && !done) { 596 ok = (yaffs2_checkpt_rd(dev, &cp, sizeof(cp)) == sizeof(cp)); 597 if (cp.struct_type != sizeof(cp)) { 598 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 599 "struct size %d instead of %d ok %d", 600 cp.struct_type, (int)sizeof(cp), ok); 601 ok = 0; 602 } 603 604 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 605 "Checkpoint read object %d parent %d type %d chunk %d ", 606 cp.obj_id, cp.parent_id, cp.variant_type, 607 cp.hdr_chunk); 608 609 if (ok && cp.obj_id == ~0) { 610 done = 1; 611 } else if (ok) { 612 obj = 613 yaffs_find_or_create_by_number(dev, cp.obj_id, 614 cp.variant_type); 615 if (obj) { 616 ok = yaffs2_checkpt_obj_to_obj(obj, &cp); 617 if (!ok) 618 break; 619 if (obj->variant_type == 620 YAFFS_OBJECT_TYPE_FILE) { 621 ok = yaffs2_rd_checkpt_tnodes(obj); 622 } else if (obj->variant_type == 623 YAFFS_OBJECT_TYPE_HARDLINK) { 624 list_add(&obj->hard_links, &hard_list); 625 } 626 } else { 627 ok = 0; 628 } 629 } 630 } 631 632 if (ok) 633 yaffs_link_fixup(dev, &hard_list); 634 635 return ok ? 1 : 0; 636 } 637 638 static int yaffs2_wr_checkpt_sum(struct yaffs_dev *dev) 639 { 640 u32 checkpt_sum; 641 int ok; 642 643 yaffs2_get_checkpt_sum(dev, &checkpt_sum); 644 645 ok = (yaffs2_checkpt_wr(dev, &checkpt_sum, sizeof(checkpt_sum)) == 646 sizeof(checkpt_sum)); 647 648 if (!ok) 649 return 0; 650 651 return 1; 652 } 653 654 static int yaffs2_rd_checkpt_sum(struct yaffs_dev *dev) 655 { 656 u32 checkpt_sum0; 657 u32 checkpt_sum1; 658 int ok; 659 660 yaffs2_get_checkpt_sum(dev, &checkpt_sum0); 661 662 ok = (yaffs2_checkpt_rd(dev, &checkpt_sum1, sizeof(checkpt_sum1)) == 663 sizeof(checkpt_sum1)); 664 665 if (!ok) 666 return 0; 667 668 if (checkpt_sum0 != checkpt_sum1) 669 return 0; 670 671 return 1; 672 } 673 674 static int yaffs2_wr_checkpt_data(struct yaffs_dev *dev) 675 { 676 int ok = 1; 677 678 if (!yaffs2_checkpt_required(dev)) { 679 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 680 "skipping checkpoint write"); 681 ok = 0; 682 } 683 684 if (ok) 685 ok = yaffs2_checkpt_open(dev, 1); 686 687 if (ok) { 688 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 689 "write checkpoint validity"); 690 ok = yaffs2_wr_checkpt_validity_marker(dev, 1); 691 } 692 if (ok) { 693 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 694 "write checkpoint device"); 695 ok = yaffs2_wr_checkpt_dev(dev); 696 } 697 if (ok) { 698 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 699 "write checkpoint objects"); 700 ok = yaffs2_wr_checkpt_objs(dev); 701 } 702 if (ok) { 703 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 704 "write checkpoint validity"); 705 ok = yaffs2_wr_checkpt_validity_marker(dev, 0); 706 } 707 708 if (ok) 709 ok = yaffs2_wr_checkpt_sum(dev); 710 711 if (!yaffs_checkpt_close(dev)) 712 ok = 0; 713 714 if (ok) 715 dev->is_checkpointed = 1; 716 else 717 dev->is_checkpointed = 0; 718 719 return dev->is_checkpointed; 720 } 721 722 static int yaffs2_rd_checkpt_data(struct yaffs_dev *dev) 723 { 724 int ok = 1; 725 726 if (!dev->param.is_yaffs2) 727 ok = 0; 728 729 if (ok && dev->param.skip_checkpt_rd) { 730 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 731 "skipping checkpoint read"); 732 ok = 0; 733 } 734 735 if (ok) 736 ok = yaffs2_checkpt_open(dev, 0); /* open for read */ 737 738 if (ok) { 739 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 740 "read checkpoint validity"); 741 ok = yaffs2_rd_checkpt_validity_marker(dev, 1); 742 } 743 if (ok) { 744 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 745 "read checkpoint device"); 746 ok = yaffs2_rd_checkpt_dev(dev); 747 } 748 if (ok) { 749 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 750 "read checkpoint objects"); 751 ok = yaffs2_rd_checkpt_objs(dev); 752 } 753 if (ok) { 754 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 755 "read checkpoint validity"); 756 ok = yaffs2_rd_checkpt_validity_marker(dev, 0); 757 } 758 759 if (ok) { 760 ok = yaffs2_rd_checkpt_sum(dev); 761 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 762 "read checkpoint checksum %d", ok); 763 } 764 765 if (!yaffs_checkpt_close(dev)) 766 ok = 0; 767 768 if (ok) 769 dev->is_checkpointed = 1; 770 else 771 dev->is_checkpointed = 0; 772 773 return ok ? 1 : 0; 774 } 775 776 void yaffs2_checkpt_invalidate(struct yaffs_dev *dev) 777 { 778 if (dev->is_checkpointed || dev->blocks_in_checkpt > 0) { 779 dev->is_checkpointed = 0; 780 yaffs2_checkpt_invalidate_stream(dev); 781 } 782 if (dev->param.sb_dirty_fn) 783 dev->param.sb_dirty_fn(dev); 784 } 785 786 int yaffs_checkpoint_save(struct yaffs_dev *dev) 787 { 788 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 789 "save entry: is_checkpointed %d", 790 dev->is_checkpointed); 791 792 yaffs_verify_objects(dev); 793 yaffs_verify_blocks(dev); 794 yaffs_verify_free_chunks(dev); 795 796 if (!dev->is_checkpointed) { 797 yaffs2_checkpt_invalidate(dev); 798 yaffs2_wr_checkpt_data(dev); 799 } 800 801 yaffs_trace(YAFFS_TRACE_CHECKPOINT | YAFFS_TRACE_MOUNT, 802 "save exit: is_checkpointed %d", 803 dev->is_checkpointed); 804 805 return dev->is_checkpointed; 806 } 807 808 int yaffs2_checkpt_restore(struct yaffs_dev *dev) 809 { 810 int retval; 811 812 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 813 "restore entry: is_checkpointed %d", 814 dev->is_checkpointed); 815 816 retval = yaffs2_rd_checkpt_data(dev); 817 818 if (dev->is_checkpointed) { 819 yaffs_verify_objects(dev); 820 yaffs_verify_blocks(dev); 821 yaffs_verify_free_chunks(dev); 822 } 823 824 yaffs_trace(YAFFS_TRACE_CHECKPOINT, 825 "restore exit: is_checkpointed %d", 826 dev->is_checkpointed); 827 828 return retval; 829 } 830 831 int yaffs2_handle_hole(struct yaffs_obj *obj, loff_t new_size) 832 { 833 /* if new_size > old_file_size. 834 * We're going to be writing a hole. 835 * If the hole is small then write zeros otherwise write a start 836 * of hole marker. 837 */ 838 loff_t old_file_size; 839 loff_t increase; 840 int small_hole; 841 int result = YAFFS_OK; 842 struct yaffs_dev *dev = NULL; 843 u8 *local_buffer = NULL; 844 int small_increase_ok = 0; 845 846 if (!obj) 847 return YAFFS_FAIL; 848 849 if (obj->variant_type != YAFFS_OBJECT_TYPE_FILE) 850 return YAFFS_FAIL; 851 852 dev = obj->my_dev; 853 854 /* Bail out if not yaffs2 mode */ 855 if (!dev->param.is_yaffs2) 856 return YAFFS_OK; 857 858 old_file_size = obj->variant.file_variant.file_size; 859 860 if (new_size <= old_file_size) 861 return YAFFS_OK; 862 863 increase = new_size - old_file_size; 864 865 if (increase < YAFFS_SMALL_HOLE_THRESHOLD * dev->data_bytes_per_chunk && 866 yaffs_check_alloc_available(dev, YAFFS_SMALL_HOLE_THRESHOLD + 1)) 867 small_hole = 1; 868 else 869 small_hole = 0; 870 871 if (small_hole) 872 local_buffer = yaffs_get_temp_buffer(dev); 873 874 if (local_buffer) { 875 /* fill hole with zero bytes */ 876 loff_t pos = old_file_size; 877 int this_write; 878 int written; 879 memset(local_buffer, 0, dev->data_bytes_per_chunk); 880 small_increase_ok = 1; 881 882 while (increase > 0 && small_increase_ok) { 883 this_write = increase; 884 if (this_write > dev->data_bytes_per_chunk) 885 this_write = dev->data_bytes_per_chunk; 886 written = 887 yaffs_do_file_wr(obj, local_buffer, pos, this_write, 888 0); 889 if (written == this_write) { 890 pos += this_write; 891 increase -= this_write; 892 } else { 893 small_increase_ok = 0; 894 } 895 } 896 897 yaffs_release_temp_buffer(dev, local_buffer); 898 899 /* If out of space then reverse any chunks we've added */ 900 if (!small_increase_ok) 901 yaffs_resize_file_down(obj, old_file_size); 902 } 903 904 if (!small_increase_ok && 905 obj->parent && 906 obj->parent->obj_id != YAFFS_OBJECTID_UNLINKED && 907 obj->parent->obj_id != YAFFS_OBJECTID_DELETED) { 908 /* Write a hole start header with the old file size */ 909 yaffs_update_oh(obj, NULL, 0, 1, 0, NULL); 910 } 911 912 return result; 913 } 914 915 struct yaffs_block_index { 916 int seq; 917 int block; 918 }; 919 920 static int yaffs2_ybicmp(const void *a, const void *b) 921 { 922 int aseq = ((struct yaffs_block_index *)a)->seq; 923 int bseq = ((struct yaffs_block_index *)b)->seq; 924 int ablock = ((struct yaffs_block_index *)a)->block; 925 int bblock = ((struct yaffs_block_index *)b)->block; 926 927 if (aseq == bseq) 928 return ablock - bblock; 929 930 return aseq - bseq; 931 } 932 933 static inline int yaffs2_scan_chunk(struct yaffs_dev *dev, 934 struct yaffs_block_info *bi, 935 int blk, int chunk_in_block, 936 int *found_chunks, 937 u8 *chunk_data, 938 struct list_head *hard_list, 939 int summary_available) 940 { 941 struct yaffs_obj_hdr *oh; 942 struct yaffs_obj *in; 943 struct yaffs_obj *parent; 944 int equiv_id; 945 loff_t file_size; 946 int is_shrink; 947 int is_unlinked; 948 struct yaffs_ext_tags tags; 949 int alloc_failed = 0; 950 int chunk = blk * dev->param.chunks_per_block + chunk_in_block; 951 struct yaffs_file_var *file_var; 952 struct yaffs_hardlink_var *hl_var; 953 struct yaffs_symlink_var *sl_var; 954 955 if (summary_available) { 956 yaffs_summary_fetch(dev, &tags, chunk_in_block); 957 tags.seq_number = bi->seq_number; 958 } 959 960 if (!summary_available || tags.obj_id == 0) { 961 yaffs_rd_chunk_tags_nand(dev, chunk, NULL, &tags); 962 dev->tags_used++; 963 } else { 964 dev->summary_used++; 965 } 966 967 /* Let's have a good look at this chunk... */ 968 969 if (!tags.chunk_used) { 970 /* An unassigned chunk in the block. 971 * If there are used chunks after this one, then 972 * it is a chunk that was skipped due to failing 973 * the erased check. Just skip it so that it can 974 * be deleted. 975 * But, more typically, We get here when this is 976 * an unallocated chunk and his means that 977 * either the block is empty or this is the one 978 * being allocated from 979 */ 980 981 if (*found_chunks) { 982 /* This is a chunk that was skipped due 983 * to failing the erased check */ 984 } else if (chunk_in_block == 0) { 985 /* We're looking at the first chunk in 986 * the block so the block is unused */ 987 bi->block_state = YAFFS_BLOCK_STATE_EMPTY; 988 dev->n_erased_blocks++; 989 } else { 990 if (bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN || 991 bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING) { 992 if (dev->seq_number == bi->seq_number) { 993 /* Allocating from this block*/ 994 yaffs_trace(YAFFS_TRACE_SCAN, 995 " Allocating from %d %d", 996 blk, chunk_in_block); 997 998 bi->block_state = 999 YAFFS_BLOCK_STATE_ALLOCATING; 1000 dev->alloc_block = blk; 1001 dev->alloc_page = chunk_in_block; 1002 dev->alloc_block_finder = blk; 1003 } else { 1004 /* This is a partially written block 1005 * that is not the current 1006 * allocation block. 1007 */ 1008 yaffs_trace(YAFFS_TRACE_SCAN, 1009 "Partially written block %d detected. gc will fix this.", 1010 blk); 1011 } 1012 } 1013 } 1014 1015 dev->n_free_chunks++; 1016 1017 } else if (tags.ecc_result == 1018 YAFFS_ECC_RESULT_UNFIXED) { 1019 yaffs_trace(YAFFS_TRACE_SCAN, 1020 " Unfixed ECC in chunk(%d:%d), chunk ignored", 1021 blk, chunk_in_block); 1022 dev->n_free_chunks++; 1023 } else if (tags.obj_id > YAFFS_MAX_OBJECT_ID || 1024 tags.chunk_id > YAFFS_MAX_CHUNK_ID || 1025 tags.obj_id == YAFFS_OBJECTID_SUMMARY || 1026 (tags.chunk_id > 0 && 1027 tags.n_bytes > dev->data_bytes_per_chunk) || 1028 tags.seq_number != bi->seq_number) { 1029 yaffs_trace(YAFFS_TRACE_SCAN, 1030 "Chunk (%d:%d) with bad tags:obj = %d, chunk_id = %d, n_bytes = %d, ignored", 1031 blk, chunk_in_block, tags.obj_id, 1032 tags.chunk_id, tags.n_bytes); 1033 dev->n_free_chunks++; 1034 } else if (tags.chunk_id > 0) { 1035 /* chunk_id > 0 so it is a data chunk... */ 1036 loff_t endpos; 1037 loff_t chunk_base = (tags.chunk_id - 1) * 1038 dev->data_bytes_per_chunk; 1039 1040 *found_chunks = 1; 1041 1042 yaffs_set_chunk_bit(dev, blk, chunk_in_block); 1043 bi->pages_in_use++; 1044 1045 in = yaffs_find_or_create_by_number(dev, 1046 tags.obj_id, 1047 YAFFS_OBJECT_TYPE_FILE); 1048 if (!in) 1049 /* Out of memory */ 1050 alloc_failed = 1; 1051 1052 if (in && 1053 in->variant_type == YAFFS_OBJECT_TYPE_FILE && 1054 chunk_base < in->variant.file_variant.shrink_size) { 1055 /* This has not been invalidated by 1056 * a resize */ 1057 if (!yaffs_put_chunk_in_file(in, tags.chunk_id, 1058 chunk, -1)) 1059 alloc_failed = 1; 1060 1061 /* File size is calculated by looking at 1062 * the data chunks if we have not 1063 * seen an object header yet. 1064 * Stop this practice once we find an 1065 * object header. 1066 */ 1067 endpos = chunk_base + tags.n_bytes; 1068 1069 if (!in->valid && 1070 in->variant.file_variant.scanned_size < endpos) { 1071 in->variant.file_variant. 1072 scanned_size = endpos; 1073 in->variant.file_variant. 1074 file_size = endpos; 1075 } 1076 } else if (in) { 1077 /* This chunk has been invalidated by a 1078 * resize, or a past file deletion 1079 * so delete the chunk*/ 1080 yaffs_chunk_del(dev, chunk, 1, __LINE__); 1081 } 1082 } else { 1083 /* chunk_id == 0, so it is an ObjectHeader. 1084 * Thus, we read in the object header and make 1085 * the object 1086 */ 1087 *found_chunks = 1; 1088 1089 yaffs_set_chunk_bit(dev, blk, chunk_in_block); 1090 bi->pages_in_use++; 1091 1092 oh = NULL; 1093 in = NULL; 1094 1095 if (tags.extra_available) { 1096 in = yaffs_find_or_create_by_number(dev, 1097 tags.obj_id, 1098 tags.extra_obj_type); 1099 if (!in) 1100 alloc_failed = 1; 1101 } 1102 1103 if (!in || 1104 (!in->valid && dev->param.disable_lazy_load) || 1105 tags.extra_shadows || 1106 (!in->valid && (tags.obj_id == YAFFS_OBJECTID_ROOT || 1107 tags.obj_id == YAFFS_OBJECTID_LOSTNFOUND))) { 1108 1109 /* If we don't have valid info then we 1110 * need to read the chunk 1111 * TODO In future we can probably defer 1112 * reading the chunk and living with 1113 * invalid data until needed. 1114 */ 1115 1116 yaffs_rd_chunk_tags_nand(dev, chunk, chunk_data, NULL); 1117 1118 oh = (struct yaffs_obj_hdr *)chunk_data; 1119 1120 if (dev->param.inband_tags) { 1121 /* Fix up the header if they got 1122 * corrupted by inband tags */ 1123 oh->shadows_obj = 1124 oh->inband_shadowed_obj_id; 1125 oh->is_shrink = 1126 oh->inband_is_shrink; 1127 } 1128 1129 if (!in) { 1130 in = yaffs_find_or_create_by_number(dev, 1131 tags.obj_id, oh->type); 1132 if (!in) 1133 alloc_failed = 1; 1134 } 1135 } 1136 1137 if (!in) { 1138 /* TODO Hoosterman we have a problem! */ 1139 yaffs_trace(YAFFS_TRACE_ERROR, 1140 "yaffs tragedy: Could not make object for object %d at chunk %d during scan", 1141 tags.obj_id, chunk); 1142 return YAFFS_FAIL; 1143 } 1144 1145 if (in->valid) { 1146 /* We have already filled this one. 1147 * We have a duplicate that will be 1148 * discarded, but we first have to suck 1149 * out resize info if it is a file. 1150 */ 1151 if ((in->variant_type == YAFFS_OBJECT_TYPE_FILE) && 1152 ((oh && oh->type == YAFFS_OBJECT_TYPE_FILE) || 1153 (tags.extra_available && 1154 tags.extra_obj_type == YAFFS_OBJECT_TYPE_FILE) 1155 )) { 1156 loff_t this_size = (oh) ? 1157 yaffs_oh_to_size(oh) : 1158 tags.extra_file_size; 1159 u32 parent_obj_id = (oh) ? 1160 oh->parent_obj_id : 1161 tags.extra_parent_id; 1162 1163 is_shrink = (oh) ? 1164 oh->is_shrink : 1165 tags.extra_is_shrink; 1166 1167 /* If it is deleted (unlinked 1168 * at start also means deleted) 1169 * we treat the file size as 1170 * being zeroed at this point. 1171 */ 1172 if (parent_obj_id == YAFFS_OBJECTID_DELETED || 1173 parent_obj_id == YAFFS_OBJECTID_UNLINKED) { 1174 this_size = 0; 1175 is_shrink = 1; 1176 } 1177 1178 if (is_shrink && 1179 in->variant.file_variant.shrink_size > 1180 this_size) 1181 in->variant.file_variant.shrink_size = 1182 this_size; 1183 1184 if (is_shrink) 1185 bi->has_shrink_hdr = 1; 1186 } 1187 /* Use existing - destroy this one. */ 1188 yaffs_chunk_del(dev, chunk, 1, __LINE__); 1189 } 1190 1191 if (!in->valid && in->variant_type != 1192 (oh ? oh->type : tags.extra_obj_type)) 1193 yaffs_trace(YAFFS_TRACE_ERROR, 1194 "yaffs tragedy: Bad object type, %d != %d, for object %d at chunk %d during scan", 1195 oh ? oh->type : tags.extra_obj_type, 1196 in->variant_type, tags.obj_id, 1197 chunk); 1198 1199 if (!in->valid && 1200 (tags.obj_id == YAFFS_OBJECTID_ROOT || 1201 tags.obj_id == YAFFS_OBJECTID_LOSTNFOUND)) { 1202 /* We only load some info, don't fiddle 1203 * with directory structure */ 1204 in->valid = 1; 1205 1206 if (oh) { 1207 in->yst_mode = oh->yst_mode; 1208 yaffs_load_attribs(in, oh); 1209 in->lazy_loaded = 0; 1210 } else { 1211 in->lazy_loaded = 1; 1212 } 1213 in->hdr_chunk = chunk; 1214 1215 } else if (!in->valid) { 1216 /* we need to load this info */ 1217 in->valid = 1; 1218 in->hdr_chunk = chunk; 1219 if (oh) { 1220 in->variant_type = oh->type; 1221 in->yst_mode = oh->yst_mode; 1222 yaffs_load_attribs(in, oh); 1223 1224 if (oh->shadows_obj > 0) 1225 yaffs_handle_shadowed_obj(dev, 1226 oh->shadows_obj, 1); 1227 1228 yaffs_set_obj_name_from_oh(in, oh); 1229 parent = yaffs_find_or_create_by_number(dev, 1230 oh->parent_obj_id, 1231 YAFFS_OBJECT_TYPE_DIRECTORY); 1232 file_size = yaffs_oh_to_size(oh); 1233 is_shrink = oh->is_shrink; 1234 equiv_id = oh->equiv_id; 1235 } else { 1236 in->variant_type = tags.extra_obj_type; 1237 parent = yaffs_find_or_create_by_number(dev, 1238 tags.extra_parent_id, 1239 YAFFS_OBJECT_TYPE_DIRECTORY); 1240 file_size = tags.extra_file_size; 1241 is_shrink = tags.extra_is_shrink; 1242 equiv_id = tags.extra_equiv_id; 1243 in->lazy_loaded = 1; 1244 } 1245 in->dirty = 0; 1246 1247 if (!parent) 1248 alloc_failed = 1; 1249 1250 /* directory stuff... 1251 * hook up to parent 1252 */ 1253 1254 if (parent && 1255 parent->variant_type == YAFFS_OBJECT_TYPE_UNKNOWN) { 1256 /* Set up as a directory */ 1257 parent->variant_type = 1258 YAFFS_OBJECT_TYPE_DIRECTORY; 1259 INIT_LIST_HEAD(&parent-> 1260 variant.dir_variant.children); 1261 } else if (!parent || 1262 parent->variant_type != 1263 YAFFS_OBJECT_TYPE_DIRECTORY) { 1264 /* Hoosterman, another problem.... 1265 * Trying to use a non-directory as a directory 1266 */ 1267 1268 yaffs_trace(YAFFS_TRACE_ERROR, 1269 "yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found." 1270 ); 1271 parent = dev->lost_n_found; 1272 } 1273 yaffs_add_obj_to_dir(parent, in); 1274 1275 is_unlinked = (parent == dev->del_dir) || 1276 (parent == dev->unlinked_dir); 1277 1278 if (is_shrink) 1279 /* Mark the block */ 1280 bi->has_shrink_hdr = 1; 1281 1282 /* Note re hardlinks. 1283 * Since we might scan a hardlink before its equivalent 1284 * object is scanned we put them all in a list. 1285 * After scanning is complete, we should have all the 1286 * objects, so we run through this list and fix up all 1287 * the chains. 1288 */ 1289 1290 switch (in->variant_type) { 1291 case YAFFS_OBJECT_TYPE_UNKNOWN: 1292 /* Todo got a problem */ 1293 break; 1294 case YAFFS_OBJECT_TYPE_FILE: 1295 file_var = &in->variant.file_variant; 1296 if (file_var->scanned_size < file_size) { 1297 /* This covers the case where the file 1298 * size is greater than the data held. 1299 * This will happen if the file is 1300 * resized to be larger than its 1301 * current data extents. 1302 */ 1303 file_var->file_size = file_size; 1304 file_var->scanned_size = file_size; 1305 } 1306 1307 if (file_var->shrink_size > file_size) 1308 file_var->shrink_size = file_size; 1309 1310 break; 1311 case YAFFS_OBJECT_TYPE_HARDLINK: 1312 hl_var = &in->variant.hardlink_variant; 1313 if (!is_unlinked) { 1314 hl_var->equiv_id = equiv_id; 1315 list_add(&in->hard_links, hard_list); 1316 } 1317 break; 1318 case YAFFS_OBJECT_TYPE_DIRECTORY: 1319 /* Do nothing */ 1320 break; 1321 case YAFFS_OBJECT_TYPE_SPECIAL: 1322 /* Do nothing */ 1323 break; 1324 case YAFFS_OBJECT_TYPE_SYMLINK: 1325 sl_var = &in->variant.symlink_variant; 1326 if (oh) { 1327 sl_var->alias = 1328 yaffs_clone_str(oh->alias); 1329 if (!sl_var->alias) 1330 alloc_failed = 1; 1331 } 1332 break; 1333 } 1334 } 1335 } 1336 return alloc_failed ? YAFFS_FAIL : YAFFS_OK; 1337 } 1338 1339 int yaffs2_scan_backwards(struct yaffs_dev *dev) 1340 { 1341 int blk; 1342 int block_iter; 1343 int start_iter; 1344 int end_iter; 1345 int n_to_scan = 0; 1346 enum yaffs_block_state state; 1347 int c; 1348 LIST_HEAD(hard_list); 1349 struct yaffs_block_info *bi; 1350 u32 seq_number; 1351 int n_blocks = dev->internal_end_block - dev->internal_start_block + 1; 1352 u8 *chunk_data; 1353 int found_chunks; 1354 int alloc_failed = 0; 1355 struct yaffs_block_index *block_index = NULL; 1356 int alt_block_index = 0; 1357 int summary_available; 1358 1359 yaffs_trace(YAFFS_TRACE_SCAN, 1360 "yaffs2_scan_backwards starts intstartblk %d intendblk %d...", 1361 dev->internal_start_block, dev->internal_end_block); 1362 1363 dev->seq_number = YAFFS_LOWEST_SEQUENCE_NUMBER; 1364 1365 block_index = 1366 kmalloc(n_blocks * sizeof(struct yaffs_block_index), GFP_NOFS); 1367 1368 if (!block_index) { 1369 block_index = 1370 vmalloc(n_blocks * sizeof(struct yaffs_block_index)); 1371 alt_block_index = 1; 1372 } 1373 1374 if (!block_index) { 1375 yaffs_trace(YAFFS_TRACE_SCAN, 1376 "yaffs2_scan_backwards() could not allocate block index!" 1377 ); 1378 return YAFFS_FAIL; 1379 } 1380 1381 dev->blocks_in_checkpt = 0; 1382 1383 chunk_data = yaffs_get_temp_buffer(dev); 1384 1385 /* Scan all the blocks to determine their state */ 1386 bi = dev->block_info; 1387 for (blk = dev->internal_start_block; blk <= dev->internal_end_block; 1388 blk++) { 1389 yaffs_clear_chunk_bits(dev, blk); 1390 bi->pages_in_use = 0; 1391 bi->soft_del_pages = 0; 1392 1393 yaffs_query_init_block_state(dev, blk, &state, &seq_number); 1394 1395 bi->block_state = state; 1396 bi->seq_number = seq_number; 1397 1398 if (bi->seq_number == YAFFS_SEQUENCE_CHECKPOINT_DATA) 1399 bi->block_state = YAFFS_BLOCK_STATE_CHECKPOINT; 1400 if (bi->seq_number == YAFFS_SEQUENCE_BAD_BLOCK) 1401 bi->block_state = YAFFS_BLOCK_STATE_DEAD; 1402 1403 yaffs_trace(YAFFS_TRACE_SCAN_DEBUG, 1404 "Block scanning block %d state %d seq %d", 1405 blk, bi->block_state, seq_number); 1406 1407 if (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT) { 1408 dev->blocks_in_checkpt++; 1409 1410 } else if (bi->block_state == YAFFS_BLOCK_STATE_DEAD) { 1411 yaffs_trace(YAFFS_TRACE_BAD_BLOCKS, 1412 "block %d is bad", blk); 1413 } else if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) { 1414 yaffs_trace(YAFFS_TRACE_SCAN_DEBUG, "Block empty "); 1415 dev->n_erased_blocks++; 1416 dev->n_free_chunks += dev->param.chunks_per_block; 1417 } else if (bi->block_state == 1418 YAFFS_BLOCK_STATE_NEEDS_SCAN) { 1419 /* Determine the highest sequence number */ 1420 if (seq_number >= YAFFS_LOWEST_SEQUENCE_NUMBER && 1421 seq_number < YAFFS_HIGHEST_SEQUENCE_NUMBER) { 1422 block_index[n_to_scan].seq = seq_number; 1423 block_index[n_to_scan].block = blk; 1424 n_to_scan++; 1425 if (seq_number >= dev->seq_number) 1426 dev->seq_number = seq_number; 1427 } else { 1428 /* TODO: Nasty sequence number! */ 1429 yaffs_trace(YAFFS_TRACE_SCAN, 1430 "Block scanning block %d has bad sequence number %d", 1431 blk, seq_number); 1432 } 1433 } 1434 bi++; 1435 } 1436 1437 yaffs_trace(YAFFS_TRACE_SCAN, "%d blocks to be sorted...", n_to_scan); 1438 1439 cond_resched(); 1440 1441 /* Sort the blocks by sequence number */ 1442 sort(block_index, n_to_scan, sizeof(struct yaffs_block_index), 1443 yaffs2_ybicmp, NULL); 1444 1445 cond_resched(); 1446 1447 yaffs_trace(YAFFS_TRACE_SCAN, "...done"); 1448 1449 /* Now scan the blocks looking at the data. */ 1450 start_iter = 0; 1451 end_iter = n_to_scan - 1; 1452 yaffs_trace(YAFFS_TRACE_SCAN_DEBUG, "%d blocks to scan", n_to_scan); 1453 1454 /* For each block.... backwards */ 1455 for (block_iter = end_iter; 1456 !alloc_failed && block_iter >= start_iter; 1457 block_iter--) { 1458 /* Cooperative multitasking! This loop can run for so 1459 long that watchdog timers expire. */ 1460 cond_resched(); 1461 1462 /* get the block to scan in the correct order */ 1463 blk = block_index[block_iter].block; 1464 bi = yaffs_get_block_info(dev, blk); 1465 1466 summary_available = yaffs_summary_read(dev, dev->sum_tags, blk); 1467 1468 /* For each chunk in each block that needs scanning.... */ 1469 found_chunks = 0; 1470 if (summary_available) 1471 c = dev->chunks_per_summary - 1; 1472 else 1473 c = dev->param.chunks_per_block - 1; 1474 1475 for (/* c is already initialised */; 1476 !alloc_failed && c >= 0 && 1477 (bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN || 1478 bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING); 1479 c--) { 1480 /* Scan backwards... 1481 * Read the tags and decide what to do 1482 */ 1483 if (yaffs2_scan_chunk(dev, bi, blk, c, 1484 &found_chunks, chunk_data, 1485 &hard_list, summary_available) == 1486 YAFFS_FAIL) 1487 alloc_failed = 1; 1488 } 1489 1490 if (bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN) { 1491 /* If we got this far while scanning, then the block 1492 * is fully allocated. */ 1493 bi->block_state = YAFFS_BLOCK_STATE_FULL; 1494 } 1495 1496 /* Now let's see if it was dirty */ 1497 if (bi->pages_in_use == 0 && 1498 !bi->has_shrink_hdr && 1499 bi->block_state == YAFFS_BLOCK_STATE_FULL) { 1500 yaffs_block_became_dirty(dev, blk); 1501 } 1502 } 1503 1504 yaffs_skip_rest_of_block(dev); 1505 1506 if (alt_block_index) 1507 vfree(block_index); 1508 else 1509 kfree(block_index); 1510 1511 /* Ok, we've done all the scanning. 1512 * Fix up the hard link chains. 1513 * We have scanned all the objects, now it's time to add these 1514 * hardlinks. 1515 */ 1516 yaffs_link_fixup(dev, &hard_list); 1517 1518 yaffs_release_temp_buffer(dev, chunk_data); 1519 1520 if (alloc_failed) 1521 return YAFFS_FAIL; 1522 1523 yaffs_trace(YAFFS_TRACE_SCAN, "yaffs2_scan_backwards ends"); 1524 1525 return YAFFS_OK; 1526 } 1527