yaffs_guts.c

   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
  14 #include "yportenv.h"
  15 #include "yaffs_trace.h"
  16
  17 #include "yaffs_guts.h"
  18 #include "yaffs_tagsvalidity.h"
  19 #include "yaffs_getblockinfo.h"
  20
  21 #include "yaffs_tagscompat.h"
  22
  23 #include "yaffs_nand.h"
  24
  25 #include "yaffs_yaffs1.h"
  26 #include "yaffs_yaffs2.h"
  27 #include "yaffs_bitmap.h"
  28 #include "yaffs_verify.h"
  29
  30 #include "yaffs_nand.h"
  31 #include "yaffs_packedtags2.h"
  32
  33 #include "yaffs_nameval.h"
  34 #include "yaffs_allocator.h"
  35
  36 #include "yaffs_attribs.h"
  37
  38 /* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
  39 #define YAFFS_GC_GOOD_ENOUGH 2
  40 #define YAFFS_GC_PASSIVE_THRESHOLD 4
  41
  42 #include "yaffs_ecc.h"
  43
  44 /* Forward declarations */
  45
  46 static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
  47                              const u8 * buffer, int n_bytes, int use_reserve);
  48
  49
  50
  51 /* Function to calculate chunk and offset */
  52
  53 static void yaffs_addr_to_chunk(struct yaffs_dev *dev, loff_t addr,
  54                                 int *chunk_out, u32 * offset_out)
  55 {
  56         int chunk;
  57         u32 offset;
  58
  59         chunk = (u32) (addr >> dev->chunk_shift);
  60
  61         if (dev->chunk_div == 1) {
  62                 /* easy power of 2 case */
  63                 offset = (u32) (addr & dev->chunk_mask);
  64         } else {
  65                 /* Non power-of-2 case */
  66
  67                 loff_t chunk_base;
  68
  69                 chunk /= dev->chunk_div;
  70
  71                 chunk_base = ((loff_t) chunk) * dev->data_bytes_per_chunk;
  72                 offset = (u32) (addr - chunk_base);
  73         }
  74
  75         *chunk_out = chunk;
  76         *offset_out = offset;
  77 }
  78
  79 /* Function to return the number of shifts for a power of 2 greater than or
  80  * equal to the given number
  81  * Note we don't try to cater for all possible numbers and this does not have to
  82  * be hellishly efficient.
  83  */
  84
  85 static u32 calc_shifts_ceiling(u32 x)
  86 {
  87         int extra_bits;
  88         int shifts;
  89
  90         shifts = extra_bits = 0;
  91
  92         while (x > 1) {
  93                 if (x & 1)
  94                         extra_bits++;
  95                 x >>= 1;
  96                 shifts++;
  97         }
  98
  99         if (extra_bits)
 100                 shifts++;
 101
 102         return shifts;
 103 }
 104
 105 /* Function to return the number of shifts to get a 1 in bit 0
 106  */
 107
 108 static u32 calc_shifts(u32 x)
 109 {
 110         u32 shifts;
 111
 112         shifts = 0;
 113
 114         if (!x)
 115                 return 0;
 116
 117         while (!(x & 1)) {
 118                 x >>= 1;
 119                 shifts++;
 120         }
 121
 122         return shifts;
 123 }
 124
 125 /*
 126  * Temporary buffer manipulations.
 127  */
 128
 129 static int yaffs_init_tmp_buffers(struct yaffs_dev *dev)
 130 {
 131         int i;
 132         u8 *buf = (u8 *) 1;
 133
 134         memset(dev->temp_buffer, 0, sizeof(dev->temp_buffer));
 135
 136         for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
 137                 dev->temp_buffer[i].line = 0;   /* not in use */
 138                 dev->temp_buffer[i].buffer = buf =
 139                     kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
 140         }
 141
 142         return buf ? YAFFS_OK : YAFFS_FAIL;
 143 }
 144
 145 u8 *yaffs_get_temp_buffer(struct yaffs_dev * dev, int line_no)
 146 {
 147         int i, j;
 148
 149         dev->temp_in_use++;
 150         if (dev->temp_in_use > dev->max_temp)
 151                 dev->max_temp = dev->temp_in_use;
 152
 153         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 154                 if (dev->temp_buffer[i].line == 0) {
 155                         dev->temp_buffer[i].line = line_no;
 156                         if ((i + 1) > dev->max_temp) {
 157                                 dev->max_temp = i + 1;
 158                                 for (j = 0; j <= i; j++)
 159                                         dev->temp_buffer[j].max_line =
 160                                             dev->temp_buffer[j].line;
 161                         }
 162
 163                         return dev->temp_buffer[i].buffer;
 164                 }
 165         }
 166
 167         yaffs_trace(YAFFS_TRACE_BUFFERS,
 168                 "Out of temp buffers at line %d, other held by lines:",
 169                 line_no);
 170         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
 171                 yaffs_trace(YAFFS_TRACE_BUFFERS," %d", dev->temp_buffer[i].line);
 172
 173         /*
 174          * If we got here then we have to allocate an unmanaged one
 175          * This is not good.
 176          */
 177
 178         dev->unmanaged_buffer_allocs++;
 179         return kmalloc(dev->data_bytes_per_chunk, GFP_NOFS);
 180
 181 }
 182
 183 void yaffs_release_temp_buffer(struct yaffs_dev *dev, u8 * buffer, int line_no)
 184 {
 185         int i;
 186
 187         dev->temp_in_use--;
 188
 189         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 190                 if (dev->temp_buffer[i].buffer == buffer) {
 191                         dev->temp_buffer[i].line = 0;
 192                         return;
 193                 }
 194         }
 195
 196         if (buffer) {
 197                 /* assume it is an unmanaged one. */
 198                 yaffs_trace(YAFFS_TRACE_BUFFERS,
 199                   "Releasing unmanaged temp buffer in line %d",
 200                    line_no);
 201                 kfree(buffer);
 202                 dev->unmanaged_buffer_deallocs++;
 203         }
 204
 205 }
 206
 207 /*
 208  * Determine if we have a managed buffer.
 209  */
 210 int yaffs_is_managed_tmp_buffer(struct yaffs_dev *dev, const u8 * buffer)
 211 {
 212         int i;
 213
 214         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 215                 if (dev->temp_buffer[i].buffer == buffer)
 216                         return 1;
 217         }
 218
 219         for (i = 0; i < dev->param.n_caches; i++) {
 220                 if (dev->cache[i].data == buffer)
 221                         return 1;
 222         }
 223
 224         if (buffer == dev->checkpt_buffer)
 225                 return 1;
 226
 227         yaffs_trace(YAFFS_TRACE_ALWAYS,
 228           "yaffs: unmaged buffer detected.");
 229         return 0;
 230 }
 231
 232 /*
 233  * Functions for robustisizing TODO
 234  *
 235  */
 236
 237 static void yaffs_handle_chunk_wr_ok(struct yaffs_dev *dev, int nand_chunk,
 238                                      const u8 * data,
 239                                      const struct yaffs_ext_tags *tags)
 240 {
 241         dev = dev;
 242         nand_chunk = nand_chunk;
 243         data = data;
 244         tags = tags;
 245 }
 246
 247 static void yaffs_handle_chunk_update(struct yaffs_dev *dev, int nand_chunk,
 248                                       const struct yaffs_ext_tags *tags)
 249 {
 250         dev = dev;
 251         nand_chunk = nand_chunk;
 252         tags = tags;
 253 }
 254
 255 void yaffs_handle_chunk_error(struct yaffs_dev *dev,
 256                               struct yaffs_block_info *bi)
 257 {
 258         if (!bi->gc_prioritise) {
 259                 bi->gc_prioritise = 1;
 260                 dev->has_pending_prioritised_gc = 1;
 261                 bi->chunk_error_strikes++;
 262
 263                 if (bi->chunk_error_strikes > 3) {
 264                         bi->needs_retiring = 1; /* Too many stikes, so retire this */
 265                         yaffs_trace(YAFFS_TRACE_ALWAYS, "yaffs: Block struck out");
 266
 267                 }
 268         }
 269 }
 270
 271 static void yaffs_handle_chunk_wr_error(struct yaffs_dev *dev, int nand_chunk,
 272                                         int erased_ok)
 273 {
 274         int flash_block = nand_chunk / dev->param.chunks_per_block;
 275         struct yaffs_block_info *bi = yaffs_get_block_info(dev, flash_block);
 276
 277         yaffs_handle_chunk_error(dev, bi);
 278
 279         if (erased_ok) {
 280                 /* Was an actual write failure, so mark the block for retirement  */
 281                 bi->needs_retiring = 1;
 282                 yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
 283                   "**>> Block %d needs retiring", flash_block);
 284         }
 285
 286         /* Delete the chunk */
 287         yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
 288         yaffs_skip_rest_of_block(dev);
 289 }
 290
 291 /*
 292  * Verification code
 293  */
 294
 295 /*
 296  *  Simple hash function. Needs to have a reasonable spread
 297  */
 298
 299 static inline int yaffs_hash_fn(int n)
 300 {
 301         n = abs(n);
 302         return n % YAFFS_NOBJECT_BUCKETS;
 303 }
 304
 305 /*
 306  * Access functions to useful fake objects.
 307  * Note that root might have a presence in NAND if permissions are set.
 308  */
 309
 310 struct yaffs_obj *yaffs_root(struct yaffs_dev *dev)
 311 {
 312         return dev->root_dir;
 313 }
 314
 315 struct yaffs_obj *yaffs_lost_n_found(struct yaffs_dev *dev)
 316 {
 317         return dev->lost_n_found;
 318 }
 319
 320 /*
 321  *  Erased NAND checking functions
 322  */
 323
 324 int yaffs_check_ff(u8 * buffer, int n_bytes)
 325 {
 326         /* Horrible, slow implementation */
 327         while (n_bytes--) {
 328                 if (*buffer != 0xFF)
 329                         return 0;
 330                 buffer++;
 331         }
 332         return 1;
 333 }
 334
 335 static int yaffs_check_chunk_erased(struct yaffs_dev *dev, int nand_chunk)
 336 {
 337         int retval = YAFFS_OK;
 338         u8 *data = yaffs_get_temp_buffer(dev, __LINE__);
 339         struct yaffs_ext_tags tags;
 340         int result;
 341
 342         result = yaffs_rd_chunk_tags_nand(dev, nand_chunk, data, &tags);
 343
 344         if (tags.ecc_result > YAFFS_ECC_RESULT_NO_ERROR)
 345                 retval = YAFFS_FAIL;
 346
 347         if (!yaffs_check_ff(data, dev->data_bytes_per_chunk) ||
 348                 tags.chunk_used) {
 349                 yaffs_trace(YAFFS_TRACE_NANDACCESS, "Chunk %d not erased", nand_chunk);
 350                 retval = YAFFS_FAIL;
 351         }
 352
 353         yaffs_release_temp_buffer(dev, data, __LINE__);
 354
 355         return retval;
 356
 357 }
 358
 359 static int yaffs_verify_chunk_written(struct yaffs_dev *dev,
 360                                       int nand_chunk,
 361                                       const u8 * data,
 362                                       struct yaffs_ext_tags *tags)
 363 {
 364         int retval = YAFFS_OK;
 365         struct yaffs_ext_tags temp_tags;
 366         u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
 367         int result;
 368
 369         result = yaffs_rd_chunk_tags_nand(dev, nand_chunk, buffer, &temp_tags);
 370         if (memcmp(buffer, data, dev->data_bytes_per_chunk) ||
 371             temp_tags.obj_id != tags->obj_id ||
 372             temp_tags.chunk_id != tags->chunk_id ||
 373             temp_tags.n_bytes != tags->n_bytes)
 374                 retval = YAFFS_FAIL;
 375
 376         yaffs_release_temp_buffer(dev, buffer, __LINE__);
 377
 378         return retval;
 379 }
 380
 381
 382 int yaffs_check_alloc_available(struct yaffs_dev *dev, int n_chunks)
 383 {
 384         int reserved_chunks;
 385         int reserved_blocks = dev->param.n_reserved_blocks;
 386         int checkpt_blocks;
 387
 388         checkpt_blocks = yaffs_calc_checkpt_blocks_required(dev);
 389
 390         reserved_chunks =
 391             ((reserved_blocks + checkpt_blocks) * dev->param.chunks_per_block);
 392
 393         return (dev->n_free_chunks > (reserved_chunks + n_chunks));
 394 }
 395
 396 static int yaffs_find_alloc_block(struct yaffs_dev *dev)
 397 {
 398         int i;
 399
 400         struct yaffs_block_info *bi;
 401
 402         if (dev->n_erased_blocks < 1) {
 403                 /* Hoosterman we've got a problem.
 404                  * Can't get space to gc
 405                  */
 406                 yaffs_trace(YAFFS_TRACE_ERROR,
 407                   "yaffs tragedy: no more erased blocks" );
 408
 409                 return -1;
 410         }
 411
 412         /* Find an empty block. */
 413
 414         for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
 415                 dev->alloc_block_finder++;
 416                 if (dev->alloc_block_finder < dev->internal_start_block
 417                     || dev->alloc_block_finder > dev->internal_end_block) {
 418                         dev->alloc_block_finder = dev->internal_start_block;
 419                 }
 420
 421                 bi = yaffs_get_block_info(dev, dev->alloc_block_finder);
 422
 423                 if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
 424                         bi->block_state = YAFFS_BLOCK_STATE_ALLOCATING;
 425                         dev->seq_number++;
 426                         bi->seq_number = dev->seq_number;
 427                         dev->n_erased_blocks--;
 428                         yaffs_trace(YAFFS_TRACE_ALLOCATE,
 429                           "Allocated block %d, seq  %d, %d left" ,
 430                            dev->alloc_block_finder, dev->seq_number,
 431                            dev->n_erased_blocks);
 432                         return dev->alloc_block_finder;
 433                 }
 434         }
 435
 436         yaffs_trace(YAFFS_TRACE_ALWAYS,
 437                 "yaffs tragedy: no more erased blocks, but there should have been %d",
 438                 dev->n_erased_blocks);
 439
 440         return -1;
 441 }
 442
 443 static int yaffs_alloc_chunk(struct yaffs_dev *dev, int use_reserver,
 444                              struct yaffs_block_info **block_ptr)
 445 {
 446         int ret_val;
 447         struct yaffs_block_info *bi;
 448
 449         if (dev->alloc_block < 0) {
 450                 /* Get next block to allocate off */
 451                 dev->alloc_block = yaffs_find_alloc_block(dev);
 452                 dev->alloc_page = 0;
 453         }
 454
 455         if (!use_reserver && !yaffs_check_alloc_available(dev, 1)) {
 456                 /* Not enough space to allocate unless we're allowed to use the reserve. */
 457                 return -1;
 458         }
 459
 460         if (dev->n_erased_blocks < dev->param.n_reserved_blocks
 461             && dev->alloc_page == 0)
 462                 yaffs_trace(YAFFS_TRACE_ALLOCATE, "Allocating reserve");
 463
 464         /* Next page please.... */
 465         if (dev->alloc_block >= 0) {
 466                 bi = yaffs_get_block_info(dev, dev->alloc_block);
 467
 468                 ret_val = (dev->alloc_block * dev->param.chunks_per_block) +
 469                     dev->alloc_page;
 470                 bi->pages_in_use++;
 471                 yaffs_set_chunk_bit(dev, dev->alloc_block, dev->alloc_page);
 472
 473                 dev->alloc_page++;
 474
 475                 dev->n_free_chunks--;
 476
 477                 /* If the block is full set the state to full */
 478                 if (dev->alloc_page >= dev->param.chunks_per_block) {
 479                         bi->block_state = YAFFS_BLOCK_STATE_FULL;
 480                         dev->alloc_block = -1;
 481                 }
 482
 483                 if (block_ptr)
 484                         *block_ptr = bi;
 485
 486                 return ret_val;
 487         }
 488
 489         yaffs_trace(YAFFS_TRACE_ERROR, "!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" );
 490
 491         return -1;
 492 }
 493
 494 static int yaffs_get_erased_chunks(struct yaffs_dev *dev)
 495 {
 496         int n;
 497
 498         n = dev->n_erased_blocks * dev->param.chunks_per_block;
 499
 500         if (dev->alloc_block > 0)
 501                 n += (dev->param.chunks_per_block - dev->alloc_page);
 502
 503         return n;
 504
 505 }
 506
 507 /*
 508  * yaffs_skip_rest_of_block() skips over the rest of the allocation block
 509  * if we don't want to write to it.
 510  */
 511 void yaffs_skip_rest_of_block(struct yaffs_dev *dev)
 512 {
 513         if (dev->alloc_block > 0) {
 514                 struct yaffs_block_info *bi =
 515                     yaffs_get_block_info(dev, dev->alloc_block);
 516                 if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING) {
 517                         bi->block_state = YAFFS_BLOCK_STATE_FULL;
 518                         dev->alloc_block = -1;
 519                 }
 520         }
 521 }
 522
 523 static int yaffs_write_new_chunk(struct yaffs_dev *dev,
 524                                  const u8 * data,
 525                                  struct yaffs_ext_tags *tags, int use_reserver)
 526 {
 527         int attempts = 0;
 528         int write_ok = 0;
 529         int chunk;
 530
 531         yaffs2_checkpt_invalidate(dev);
 532
 533         do {
 534                 struct yaffs_block_info *bi = 0;
 535                 int erased_ok = 0;
 536
 537                 chunk = yaffs_alloc_chunk(dev, use_reserver, &bi);
 538                 if (chunk < 0) {
 539                         /* no space */
 540                         break;
 541                 }
 542
 543                 /* First check this chunk is erased, if it needs
 544                  * checking.  The checking policy (unless forced
 545                  * always on) is as follows:
 546                  *
 547                  * Check the first page we try to write in a block.
 548                  * If the check passes then we don't need to check any
 549                  * more.        If the check fails, we check again...
 550                  * If the block has been erased, we don't need to check.
 551                  *
 552                  * However, if the block has been prioritised for gc,
 553                  * then we think there might be something odd about
 554                  * this block and stop using it.
 555                  *
 556                  * Rationale: We should only ever see chunks that have
 557                  * not been erased if there was a partially written
 558                  * chunk due to power loss.  This checking policy should
 559                  * catch that case with very few checks and thus save a
 560                  * lot of checks that are most likely not needed.
 561                  *
 562                  * Mods to the above
 563                  * If an erase check fails or the write fails we skip the
 564                  * rest of the block.
 565                  */
 566
 567                 /* let's give it a try */
 568                 attempts++;
 569
 570                 if (dev->param.always_check_erased)
 571                         bi->skip_erased_check = 0;
 572
 573                 if (!bi->skip_erased_check) {
 574                         erased_ok = yaffs_check_chunk_erased(dev, chunk);
 575                         if (erased_ok != YAFFS_OK) {
 576                                 yaffs_trace(YAFFS_TRACE_ERROR,
 577                                   "**>> yaffs chunk %d was not erased",
 578                                   chunk);
 579
 580                                 /* If not erased, delete this one,
 581                                  * skip rest of block and
 582                                  * try another chunk */
 583                                 yaffs_chunk_del(dev, chunk, 1, __LINE__);
 584                                 yaffs_skip_rest_of_block(dev);
 585                                 continue;
 586                         }
 587                 }
 588
 589                 write_ok = yaffs_wr_chunk_tags_nand(dev, chunk, data, tags);
 590
 591                 if (!bi->skip_erased_check)
 592                         write_ok =
 593                             yaffs_verify_chunk_written(dev, chunk, data, tags);
 594
 595                 if (write_ok != YAFFS_OK) {
 596                         /* Clean up aborted write, skip to next block and
 597                          * try another chunk */
 598                         yaffs_handle_chunk_wr_error(dev, chunk, erased_ok);
 599                         continue;
 600                 }
 601
 602                 bi->skip_erased_check = 1;
 603
 604                 /* Copy the data into the robustification buffer */
 605                 yaffs_handle_chunk_wr_ok(dev, chunk, data, tags);
 606
 607         } while (write_ok != YAFFS_OK &&
 608                  (yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
 609
 610         if (!write_ok)
 611                 chunk = -1;
 612
 613         if (attempts > 1) {
 614                 yaffs_trace(YAFFS_TRACE_ERROR,
 615                         "**>> yaffs write required %d attempts",
 616                         attempts);
 617                 dev->n_retired_writes += (attempts - 1);
 618         }
 619
 620         return chunk;
 621 }
 622
 623 /*
 624  * Block retiring for handling a broken block.
 625  */
 626
 627 static void yaffs_retire_block(struct yaffs_dev *dev, int flash_block)
 628 {
 629         struct yaffs_block_info *bi = yaffs_get_block_info(dev, flash_block);
 630
 631         yaffs2_checkpt_invalidate(dev);
 632
 633         yaffs2_clear_oldest_dirty_seq(dev, bi);
 634
 635         if (yaffs_mark_bad(dev, flash_block) != YAFFS_OK) {
 636                 if (yaffs_erase_block(dev, flash_block) != YAFFS_OK) {
 637                         yaffs_trace(YAFFS_TRACE_ALWAYS,
 638                                 "yaffs: Failed to mark bad and erase block %d",
 639                                 flash_block);
 640                 } else {
 641                         struct yaffs_ext_tags tags;
 642                         int chunk_id =
 643                             flash_block * dev->param.chunks_per_block;
 644
 645                         u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
 646
 647                         memset(buffer, 0xff, dev->data_bytes_per_chunk);
 648                         yaffs_init_tags(&tags);
 649                         tags.seq_number = YAFFS_SEQUENCE_BAD_BLOCK;
 650                         if (dev->param.write_chunk_tags_fn(dev, chunk_id -
 651                                                            dev->chunk_offset,
 652                                                            buffer,
 653                                                            &tags) != YAFFS_OK)
 654                                 yaffs_trace(YAFFS_TRACE_ALWAYS,
 655                                         "yaffs: Failed to write bad block marker to block %d",
 656                                         flash_block);
 657
 658                         yaffs_release_temp_buffer(dev, buffer, __LINE__);
 659                 }
 660         }
 661
 662         bi->block_state = YAFFS_BLOCK_STATE_DEAD;
 663         bi->gc_prioritise = 0;
 664         bi->needs_retiring = 0;
 665
 666         dev->n_retired_blocks++;
 667 }
 668
 669 /*---------------- Name handling functions ------------*/
 670
 671 static u16 yaffs_calc_name_sum(const YCHAR * name)
 672 {
 673         u16 sum = 0;
 674         u16 i = 1;
 675
 676         const YUCHAR *bname = (const YUCHAR *)name;
 677         if (bname) {
 678                 while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH / 2))) {
 679
 680                         /* 0x1f mask is case insensitive */
 681                         sum += ((*bname) & 0x1f) * i;
 682                         i++;
 683                         bname++;
 684                 }
 685         }
 686         return sum;
 687 }
 688
 689 void yaffs_set_obj_name(struct yaffs_obj *obj, const YCHAR * name)
 690 {
 691 #ifndef CONFIG_YAFFS_NO_SHORT_NAMES
 692         memset(obj->short_name, 0, sizeof(obj->short_name));
 693         if (name &&
 694                 strnlen(name, YAFFS_SHORT_NAME_LENGTH + 1) <=
 695             YAFFS_SHORT_NAME_LENGTH)
 696                 strcpy(obj->short_name, name);
 697         else
 698                 obj->short_name[0] = _Y('\0');
 699 #endif
 700         obj->sum = yaffs_calc_name_sum(name);
 701 }
 702
 703 void yaffs_set_obj_name_from_oh(struct yaffs_obj *obj,
 704                                 const struct yaffs_obj_hdr *oh)
 705 {
 706 #ifdef CONFIG_YAFFS_AUTO_UNICODE
 707         YCHAR tmp_name[YAFFS_MAX_NAME_LENGTH + 1];
 708         memset(tmp_name, 0, sizeof(tmp_name));
 709         yaffs_load_name_from_oh(obj->my_dev, tmp_name, oh->name,
 710                                 YAFFS_MAX_NAME_LENGTH + 1);
 711         yaffs_set_obj_name(obj, tmp_name);
 712 #else
 713         yaffs_set_obj_name(obj, oh->name);
 714 #endif
 715 }
 716
 717 /*-------------------- TNODES -------------------
 718
 719  * List of spare tnodes
 720  * The list is hooked together using the first pointer
 721  * in the tnode.
 722  */
 723
 724 struct yaffs_tnode *yaffs_get_tnode(struct yaffs_dev *dev)
 725 {
 726         struct yaffs_tnode *tn = yaffs_alloc_raw_tnode(dev);
 727         if (tn) {
 728                 memset(tn, 0, dev->tnode_size);
 729                 dev->n_tnodes++;
 730         }
 731
 732         dev->checkpoint_blocks_required = 0;    /* force recalculation */
 733
 734         return tn;
 735 }
 736
 737 /* FreeTnode frees up a tnode and puts it back on the free list */
 738 static void yaffs_free_tnode(struct yaffs_dev *dev, struct yaffs_tnode *tn)
 739 {
 740         yaffs_free_raw_tnode(dev, tn);
 741         dev->n_tnodes--;
 742         dev->checkpoint_blocks_required = 0;    /* force recalculation */
 743 }
 744
 745 static void yaffs_deinit_tnodes_and_objs(struct yaffs_dev *dev)
 746 {
 747         yaffs_deinit_raw_tnodes_and_objs(dev);
 748         dev->n_obj = 0;
 749         dev->n_tnodes = 0;
 750 }
 751
 752 void yaffs_load_tnode_0(struct yaffs_dev *dev, struct yaffs_tnode *tn,
 753                         unsigned pos, unsigned val)
 754 {
 755         u32 *map = (u32 *) tn;
 756         u32 bit_in_map;
 757         u32 bit_in_word;
 758         u32 word_in_map;
 759         u32 mask;
 760
 761         pos &= YAFFS_TNODES_LEVEL0_MASK;
 762         val >>= dev->chunk_grp_bits;
 763
 764         bit_in_map = pos * dev->tnode_width;
 765         word_in_map = bit_in_map / 32;
 766         bit_in_word = bit_in_map & (32 - 1);
 767
 768         mask = dev->tnode_mask << bit_in_word;
 769
 770         map[word_in_map] &= ~mask;
 771         map[word_in_map] |= (mask & (val << bit_in_word));
 772
 773         if (dev->tnode_width > (32 - bit_in_word)) {
 774                 bit_in_word = (32 - bit_in_word);
 775                 word_in_map++;;
 776                 mask =
 777                     dev->tnode_mask >> ( /*dev->tnode_width - */ bit_in_word);
 778                 map[word_in_map] &= ~mask;
 779                 map[word_in_map] |= (mask & (val >> bit_in_word));
 780         }
 781 }
 782
 783 u32 yaffs_get_group_base(struct yaffs_dev *dev, struct yaffs_tnode *tn,
 784                          unsigned pos)
 785 {
 786         u32 *map = (u32 *) tn;
 787         u32 bit_in_map;
 788         u32 bit_in_word;
 789         u32 word_in_map;
 790         u32 val;
 791
 792         pos &= YAFFS_TNODES_LEVEL0_MASK;
 793
 794         bit_in_map = pos * dev->tnode_width;
 795         word_in_map = bit_in_map / 32;
 796         bit_in_word = bit_in_map & (32 - 1);
 797
 798         val = map[word_in_map] >> bit_in_word;
 799
 800         if (dev->tnode_width > (32 - bit_in_word)) {
 801                 bit_in_word = (32 - bit_in_word);
 802                 word_in_map++;;
 803                 val |= (map[word_in_map] << bit_in_word);
 804         }
 805
 806         val &= dev->tnode_mask;
 807         val <<= dev->chunk_grp_bits;
 808
 809         return val;
 810 }
 811
 812 /* ------------------- End of individual tnode manipulation -----------------*/
 813
 814 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 815  * The look up tree is represented by the top tnode and the number of top_level
 816  * in the tree. 0 means only the level 0 tnode is in the tree.
 817  */
 818
 819 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
 820 struct yaffs_tnode *yaffs_find_tnode_0(struct yaffs_dev *dev,
 821                                        struct yaffs_file_var *file_struct,
 822                                        u32 chunk_id)
 823 {
 824         struct yaffs_tnode *tn = file_struct->top;
 825         u32 i;
 826         int required_depth;
 827         int level = file_struct->top_level;
 828
 829         dev = dev;
 830
 831         /* Check sane level and chunk Id */
 832         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
 833                 return NULL;
 834
 835         if (chunk_id > YAFFS_MAX_CHUNK_ID)
 836                 return NULL;
 837
 838         /* First check we're tall enough (ie enough top_level) */
 839
 840         i = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
 841         required_depth = 0;
 842         while (i) {
 843                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 844                 required_depth++;
 845         }
 846
 847         if (required_depth > file_struct->top_level)
 848                 return NULL;    /* Not tall enough, so we can't find it */
 849
 850         /* Traverse down to level 0 */
 851         while (level > 0 && tn) {
 852                 tn = tn->internal[(chunk_id >>
 853                                    (YAFFS_TNODES_LEVEL0_BITS +
 854                                     (level - 1) *
 855                                     YAFFS_TNODES_INTERNAL_BITS)) &
 856                                   YAFFS_TNODES_INTERNAL_MASK];
 857                 level--;
 858         }
 859
 860         return tn;
 861 }
 862
 863 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 864  * This happens in two steps:
 865  *  1. If the tree isn't tall enough, then make it taller.
 866  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 867  *
 868  * Used when modifying the tree.
 869  *
 870  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
 871  *  be plugged into the ttree.
 872  */
 873
 874 struct yaffs_tnode *yaffs_add_find_tnode_0(struct yaffs_dev *dev,
 875                                            struct yaffs_file_var *file_struct,
 876                                            u32 chunk_id,
 877                                            struct yaffs_tnode *passed_tn)
 878 {
 879         int required_depth;
 880         int i;
 881         int l;
 882         struct yaffs_tnode *tn;
 883
 884         u32 x;
 885
 886         /* Check sane level and page Id */
 887         if (file_struct->top_level < 0
 888             || file_struct->top_level > YAFFS_TNODES_MAX_LEVEL)
 889                 return NULL;
 890
 891         if (chunk_id > YAFFS_MAX_CHUNK_ID)
 892                 return NULL;
 893
 894         /* First check we're tall enough (ie enough top_level) */
 895
 896         x = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
 897         required_depth = 0;
 898         while (x) {
 899                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 900                 required_depth++;
 901         }
 902
 903         if (required_depth > file_struct->top_level) {
 904                 /* Not tall enough, gotta make the tree taller */
 905                 for (i = file_struct->top_level; i < required_depth; i++) {
 906
 907                         tn = yaffs_get_tnode(dev);
 908
 909                         if (tn) {
 910                                 tn->internal[0] = file_struct->top;
 911                                 file_struct->top = tn;
 912                                 file_struct->top_level++;
 913                         } else {
 914                                 yaffs_trace(YAFFS_TRACE_ERROR, "yaffs: no more tnodes");
 915                                 return NULL;
 916                         }
 917                 }
 918         }
 919
 920         /* Traverse down to level 0, adding anything we need */
 921
 922         l = file_struct->top_level;
 923         tn = file_struct->top;
 924
 925         if (l > 0) {
 926                 while (l > 0 && tn) {
 927                         x = (chunk_id >>
 928                              (YAFFS_TNODES_LEVEL0_BITS +
 929                               (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
 930                             YAFFS_TNODES_INTERNAL_MASK;
 931
 932                         if ((l > 1) && !tn->internal[x]) {
 933                                 /* Add missing non-level-zero tnode */
 934                                 tn->internal[x] = yaffs_get_tnode(dev);
 935                                 if (!tn->internal[x])
 936                                         return NULL;
 937                         } else if (l == 1) {
 938                                 /* Looking from level 1 at level 0 */
 939                                 if (passed_tn) {
 940                                         /* If we already have one, then release it. */
 941                                         if (tn->internal[x])
 942                                                 yaffs_free_tnode(dev,
 943                                                                  tn->
 944                                                                  internal[x]);
 945                                         tn->internal[x] = passed_tn;
 946
 947                                 } else if (!tn->internal[x]) {
 948                                         /* Don't have one, none passed in */
 949                                         tn->internal[x] = yaffs_get_tnode(dev);
 950                                         if (!tn->internal[x])
 951                                                 return NULL;
 952                                 }
 953                         }
 954
 955                         tn = tn->internal[x];
 956                         l--;
 957                 }
 958         } else {
 959                 /* top is level 0 */
 960                 if (passed_tn) {
 961                         memcpy(tn, passed_tn,
 962                                (dev->tnode_width * YAFFS_NTNODES_LEVEL0) / 8);
 963                         yaffs_free_tnode(dev, passed_tn);
 964                 }
 965         }
 966
 967         return tn;
 968 }
 969
 970 static int yaffs_tags_match(const struct yaffs_ext_tags *tags, int obj_id,
 971                             int chunk_obj)
 972 {
 973         return (tags->chunk_id == chunk_obj &&
 974                 tags->obj_id == obj_id && !tags->is_deleted) ? 1 : 0;
 975
 976 }
 977
 978 static int yaffs_find_chunk_in_group(struct yaffs_dev *dev, int the_chunk,
 979                                      struct yaffs_ext_tags *tags, int obj_id,
 980                                      int inode_chunk)
 981 {
 982         int j;
 983
 984         for (j = 0; the_chunk && j < dev->chunk_grp_size; j++) {
 985                 if (yaffs_check_chunk_bit
 986                     (dev, the_chunk / dev->param.chunks_per_block,
 987                      the_chunk % dev->param.chunks_per_block)) {
 988
 989                         if (dev->chunk_grp_size == 1)
 990                                 return the_chunk;
 991                         else {
 992                                 yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL,
 993                                                          tags);
 994                                 if (yaffs_tags_match(tags, obj_id, inode_chunk)) {
 995                                         /* found it; */
 996                                         return the_chunk;
 997                                 }
 998                         }
 999                 }
1000                 the_chunk++;
1001         }
1002         return -1;
1003 }
1004
1005 static int yaffs_find_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
1006                                     struct yaffs_ext_tags *tags)
1007 {
1008         /*Get the Tnode, then get the level 0 offset chunk offset */
1009         struct yaffs_tnode *tn;
1010         int the_chunk = -1;
1011         struct yaffs_ext_tags local_tags;
1012         int ret_val = -1;
1013
1014         struct yaffs_dev *dev = in->my_dev;
1015
1016         if (!tags) {
1017                 /* Passed a NULL, so use our own tags space */
1018                 tags = &local_tags;
1019         }
1020
1021         tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
1022
1023         if (tn) {
1024                 the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
1025
1026                 ret_val =
1027                     yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
1028                                               inode_chunk);
1029         }
1030         return ret_val;
1031 }
1032
1033 static int yaffs_find_del_file_chunk(struct yaffs_obj *in, int inode_chunk,
1034                                      struct yaffs_ext_tags *tags)
1035 {
1036         /* Get the Tnode, then get the level 0 offset chunk offset */
1037         struct yaffs_tnode *tn;
1038         int the_chunk = -1;
1039         struct yaffs_ext_tags local_tags;
1040
1041         struct yaffs_dev *dev = in->my_dev;
1042         int ret_val = -1;
1043
1044         if (!tags) {
1045                 /* Passed a NULL, so use our own tags space */
1046                 tags = &local_tags;
1047         }
1048
1049         tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
1050
1051         if (tn) {
1052
1053                 the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
1054
1055                 ret_val =
1056                     yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
1057                                               inode_chunk);
1058
1059                 /* Delete the entry in the filestructure (if found) */
1060                 if (ret_val != -1)
1061                         yaffs_load_tnode_0(dev, tn, inode_chunk, 0);
1062         }
1063
1064         return ret_val;
1065 }
1066
1067 int yaffs_put_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
1068                             int nand_chunk, int in_scan)
1069 {
1070         /* NB in_scan is zero unless scanning.
1071          * For forward scanning, in_scan is > 0;
1072          * for backward scanning in_scan is < 0
1073          *
1074          * nand_chunk = 0 is a dummy insert to make sure the tnodes are there.
1075          */
1076
1077         struct yaffs_tnode *tn;
1078         struct yaffs_dev *dev = in->my_dev;
1079         int existing_cunk;
1080         struct yaffs_ext_tags existing_tags;
1081         struct yaffs_ext_tags new_tags;
1082         unsigned existing_serial, new_serial;
1083
1084         if (in->variant_type != YAFFS_OBJECT_TYPE_FILE) {
1085                 /* Just ignore an attempt at putting a chunk into a non-file during scanning
1086                  * If it is not during Scanning then something went wrong!
1087                  */
1088                 if (!in_scan) {
1089                         yaffs_trace(YAFFS_TRACE_ERROR,
1090                                 "yaffs tragedy:attempt to put data chunk into a non-file"
1091                                 );
1092                         YBUG();
1093                 }
1094
1095                 yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
1096                 return YAFFS_OK;
1097         }
1098
1099         tn = yaffs_add_find_tnode_0(dev,
1100                                     &in->variant.file_variant,
1101                                     inode_chunk, NULL);
1102         if (!tn)
1103                 return YAFFS_FAIL;
1104
1105         if (!nand_chunk)
1106                 /* Dummy insert, bail now */
1107                 return YAFFS_OK;
1108
1109         existing_cunk = yaffs_get_group_base(dev, tn, inode_chunk);
1110
1111         if (in_scan != 0) {
1112                 /* If we're scanning then we need to test for duplicates
1113                  * NB This does not need to be efficient since it should only ever
1114                  * happen when the power fails during a write, then only one
1115                  * chunk should ever be affected.
1116                  *
1117                  * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
1118                  * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
1119                  */
1120
1121                 if (existing_cunk > 0) {
1122                         /* NB Right now existing chunk will not be real chunk_id if the chunk group size > 1
1123                          *    thus we have to do a FindChunkInFile to get the real chunk id.
1124                          *
1125                          * We have a duplicate now we need to decide which one to use:
1126                          *
1127                          * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
1128                          * Forward scanning YAFFS2: The new one is what we use, dump the old one.
1129                          * YAFFS1: Get both sets of tags and compare serial numbers.
1130                          */
1131
1132                         if (in_scan > 0) {
1133                                 /* Only do this for forward scanning */
1134                                 yaffs_rd_chunk_tags_nand(dev,
1135                                                          nand_chunk,
1136                                                          NULL, &new_tags);
1137
1138                                 /* Do a proper find */
1139                                 existing_cunk =
1140                                     yaffs_find_chunk_in_file(in, inode_chunk,
1141                                                              &existing_tags);
1142                         }
1143
1144                         if (existing_cunk <= 0) {
1145                                 /*Hoosterman - how did this happen? */
1146
1147                                 yaffs_trace(YAFFS_TRACE_ERROR,
1148                                         "yaffs tragedy: existing chunk < 0 in scan"
1149                                         );
1150
1151                         }
1152
1153                         /* NB The deleted flags should be false, otherwise the chunks will
1154                          * not be loaded during a scan
1155                          */
1156
1157                         if (in_scan > 0) {
1158                                 new_serial = new_tags.serial_number;
1159                                 existing_serial = existing_tags.serial_number;
1160                         }
1161
1162                         if ((in_scan > 0) &&
1163                             (existing_cunk <= 0 ||
1164                              ((existing_serial + 1) & 3) == new_serial)) {
1165                                 /* Forward scanning.
1166                                  * Use new
1167                                  * Delete the old one and drop through to update the tnode
1168                                  */
1169                                 yaffs_chunk_del(dev, existing_cunk, 1,
1170                                                 __LINE__);
1171                         } else {
1172                                 /* Backward scanning or we want to use the existing one
1173                                  * Use existing.
1174                                  * Delete the new one and return early so that the tnode isn't changed
1175                                  */
1176                                 yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
1177                                 return YAFFS_OK;
1178                         }
1179                 }
1180
1181         }
1182
1183         if (existing_cunk == 0)
1184                 in->n_data_chunks++;
1185
1186         yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
1187
1188         return YAFFS_OK;
1189 }
1190
1191 static void yaffs_soft_del_chunk(struct yaffs_dev *dev, int chunk)
1192 {
1193         struct yaffs_block_info *the_block;
1194         unsigned block_no;
1195
1196         yaffs_trace(YAFFS_TRACE_DELETION, "soft delete chunk %d", chunk);
1197
1198         block_no = chunk / dev->param.chunks_per_block;
1199         the_block = yaffs_get_block_info(dev, block_no);
1200         if (the_block) {
1201                 the_block->soft_del_pages++;
1202                 dev->n_free_chunks++;
1203                 yaffs2_update_oldest_dirty_seq(dev, block_no, the_block);
1204         }
1205 }
1206
1207 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1208  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1209  * of the tnode.
1210  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1211  */
1212
1213 static int yaffs_soft_del_worker(struct yaffs_obj *in, struct yaffs_tnode *tn,
1214                                  u32 level, int chunk_offset)
1215 {
1216         int i;
1217         int the_chunk;
1218         int all_done = 1;
1219         struct yaffs_dev *dev = in->my_dev;
1220
1221         if (tn) {
1222                 if (level > 0) {
1223
1224                         for (i = YAFFS_NTNODES_INTERNAL - 1; all_done && i >= 0;
1225                              i--) {
1226                                 if (tn->internal[i]) {
1227                                         all_done =
1228                                             yaffs_soft_del_worker(in,
1229                                                                   tn->internal
1230                                                                   [i],
1231                                                                   level - 1,
1232                                                                   (chunk_offset
1233                                                                    <<
1234                                                                    YAFFS_TNODES_INTERNAL_BITS)
1235                                                                   + i);
1236                                         if (all_done) {
1237                                                 yaffs_free_tnode(dev,
1238                                                                  tn->internal
1239                                                                  [i]);
1240                                                 tn->internal[i] = NULL;
1241                                         } else {
1242                                                 /* Hoosterman... how could this happen? */
1243                                         }
1244                                 }
1245                         }
1246                         return (all_done) ? 1 : 0;
1247                 } else if (level == 0) {
1248
1249                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1250                                 the_chunk = yaffs_get_group_base(dev, tn, i);
1251                                 if (the_chunk) {
1252                                         /* Note this does not find the real chunk, only the chunk group.
1253                                          * We make an assumption that a chunk group is not larger than
1254                                          * a block.
1255                                          */
1256                                         yaffs_soft_del_chunk(dev, the_chunk);
1257                                         yaffs_load_tnode_0(dev, tn, i, 0);
1258                                 }
1259
1260                         }
1261                         return 1;
1262
1263                 }
1264
1265         }
1266
1267         return 1;
1268
1269 }
1270
1271 static void yaffs_remove_obj_from_dir(struct yaffs_obj *obj)
1272 {
1273         struct yaffs_dev *dev = obj->my_dev;
1274         struct yaffs_obj *parent;
1275
1276         yaffs_verify_obj_in_dir(obj);
1277         parent = obj->parent;
1278
1279         yaffs_verify_dir(parent);
1280
1281         if (dev && dev->param.remove_obj_fn)
1282                 dev->param.remove_obj_fn(obj);
1283
1284         list_del_init(&obj->siblings);
1285         obj->parent = NULL;
1286
1287         yaffs_verify_dir(parent);
1288 }
1289
1290 void yaffs_add_obj_to_dir(struct yaffs_obj *directory, struct yaffs_obj *obj)
1291 {
1292         if (!directory) {
1293                 yaffs_trace(YAFFS_TRACE_ALWAYS,
1294                         "tragedy: Trying to add an object to a null pointer directory"
1295                         );
1296                 YBUG();
1297                 return;
1298         }
1299         if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
1300                 yaffs_trace(YAFFS_TRACE_ALWAYS,
1301                         "tragedy: Trying to add an object to a non-directory"
1302                         );
1303                 YBUG();
1304         }
1305
1306         if (obj->siblings.prev == NULL) {
1307                 /* Not initialised */
1308                 YBUG();
1309         }
1310
1311         yaffs_verify_dir(directory);
1312
1313         yaffs_remove_obj_from_dir(obj);
1314
1315         /* Now add it */
1316         list_add(&obj->siblings, &directory->variant.dir_variant.children);
1317         obj->parent = directory;
1318
1319         if (directory == obj->my_dev->unlinked_dir
1320             || directory == obj->my_dev->del_dir) {
1321                 obj->unlinked = 1;
1322                 obj->my_dev->n_unlinked_files++;
1323                 obj->rename_allowed = 0;
1324         }
1325
1326         yaffs_verify_dir(directory);
1327         yaffs_verify_obj_in_dir(obj);
1328 }
1329
1330 static int yaffs_change_obj_name(struct yaffs_obj *obj,
1331                                  struct yaffs_obj *new_dir,
1332                                  const YCHAR * new_name, int force, int shadows)
1333 {
1334         int unlink_op;
1335         int del_op;
1336
1337         struct yaffs_obj *existing_target;
1338
1339         if (new_dir == NULL)
1340                 new_dir = obj->parent;  /* use the old directory */
1341
1342         if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
1343                 yaffs_trace(YAFFS_TRACE_ALWAYS,
1344                         "tragedy: yaffs_change_obj_name: new_dir is not a directory"
1345                         );
1346                 YBUG();
1347         }
1348
1349         /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
1350         if (obj->my_dev->param.is_yaffs2)
1351                 unlink_op = (new_dir == obj->my_dev->unlinked_dir);
1352         else
1353                 unlink_op = (new_dir == obj->my_dev->unlinked_dir
1354                              && obj->variant_type == YAFFS_OBJECT_TYPE_FILE);
1355
1356         del_op = (new_dir == obj->my_dev->del_dir);
1357
1358         existing_target = yaffs_find_by_name(new_dir, new_name);
1359
1360         /* If the object is a file going into the unlinked directory,
1361          *   then it is OK to just stuff it in since duplicate names are allowed.
1362          *   else only proceed if the new name does not exist and if we're putting
1363          *   it into a directory.
1364          */
1365         if ((unlink_op ||
1366              del_op ||
1367              force ||
1368              (shadows > 0) ||
1369              !existing_target) &&
1370             new_dir->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) {
1371                 yaffs_set_obj_name(obj, new_name);
1372                 obj->dirty = 1;
1373
1374                 yaffs_add_obj_to_dir(new_dir, obj);
1375
1376                 if (unlink_op)
1377                         obj->unlinked = 1;
1378
1379                 /* If it is a deletion then we mark it as a shrink for gc purposes. */
1380                 if (yaffs_update_oh(obj, new_name, 0, del_op, shadows, NULL) >=
1381                     0)
1382                         return YAFFS_OK;
1383         }
1384
1385         return YAFFS_FAIL;
1386 }
1387
1388 /*------------------------ Short Operations Cache ----------------------------------------
1389  *   In many situations where there is no high level buffering  a lot of
1390  *   reads might be short sequential reads, and a lot of writes may be short
1391  *   sequential writes. eg. scanning/writing a jpeg file.
1392  *   In these cases, a short read/write cache can provide a huge perfomance
1393  *   benefit with dumb-as-a-rock code.
1394  *   In Linux, the page cache provides read buffering and the short op cache
1395  *   provides write buffering.
1396  *
1397  *   There are a limited number (~10) of cache chunks per device so that we don't
1398  *   need a very intelligent search.
1399  */
1400
1401 static int yaffs_obj_cache_dirty(struct yaffs_obj *obj)
1402 {
1403         struct yaffs_dev *dev = obj->my_dev;
1404         int i;
1405         struct yaffs_cache *cache;
1406         int n_caches = obj->my_dev->param.n_caches;
1407
1408         for (i = 0; i < n_caches; i++) {
1409                 cache = &dev->cache[i];
1410                 if (cache->object == obj && cache->dirty)
1411                         return 1;
1412         }
1413
1414         return 0;
1415 }
1416
1417 static void yaffs_flush_file_cache(struct yaffs_obj *obj)
1418 {
1419         struct yaffs_dev *dev = obj->my_dev;
1420         int lowest = -99;       /* Stop compiler whining. */
1421         int i;
1422         struct yaffs_cache *cache;
1423         int chunk_written = 0;
1424         int n_caches = obj->my_dev->param.n_caches;
1425
1426         if (n_caches > 0) {
1427                 do {
1428                         cache = NULL;
1429
1430                         /* Find the dirty cache for this object with the lowest chunk id. */
1431                         for (i = 0; i < n_caches; i++) {
1432                                 if (dev->cache[i].object == obj &&
1433                                     dev->cache[i].dirty) {
1434                                         if (!cache
1435                                             || dev->cache[i].chunk_id <
1436                                             lowest) {
1437                                                 cache = &dev->cache[i];
1438                                                 lowest = cache->chunk_id;
1439                                         }
1440                                 }
1441                         }
1442
1443                         if (cache && !cache->locked) {
1444                                 /* Write it out and free it up */
1445
1446                                 chunk_written =
1447                                     yaffs_wr_data_obj(cache->object,
1448                                                       cache->chunk_id,
1449                                                       cache->data,
1450                                                       cache->n_bytes, 1);
1451                                 cache->dirty = 0;
1452                                 cache->object = NULL;
1453                         }
1454
1455                 } while (cache && chunk_written > 0);
1456
1457                 if (cache)
1458                         /* Hoosterman, disk full while writing cache out. */
1459                         yaffs_trace(YAFFS_TRACE_ERROR,
1460                                 "yaffs tragedy: no space during cache write");
1461
1462         }
1463
1464 }
1465
1466 /*yaffs_flush_whole_cache(dev)
1467  *
1468  *
1469  */
1470
1471 void yaffs_flush_whole_cache(struct yaffs_dev *dev)
1472 {
1473         struct yaffs_obj *obj;
1474         int n_caches = dev->param.n_caches;
1475         int i;
1476
1477         /* Find a dirty object in the cache and flush it...
1478          * until there are no further dirty objects.
1479          */
1480         do {
1481                 obj = NULL;
1482                 for (i = 0; i < n_caches && !obj; i++) {
1483                         if (dev->cache[i].object && dev->cache[i].dirty)
1484                                 obj = dev->cache[i].object;
1485
1486                 }
1487                 if (obj)
1488                         yaffs_flush_file_cache(obj);
1489
1490         } while (obj);
1491
1492 }
1493
1494 /* Grab us a cache chunk for use.
1495  * First look for an empty one.
1496  * Then look for the least recently used non-dirty one.
1497  * Then look for the least recently used dirty one...., flush and look again.
1498  */
1499 static struct yaffs_cache *yaffs_grab_chunk_worker(struct yaffs_dev *dev)
1500 {
1501         int i;
1502
1503         if (dev->param.n_caches > 0) {
1504                 for (i = 0; i < dev->param.n_caches; i++) {
1505                         if (!dev->cache[i].object)
1506                                 return &dev->cache[i];
1507                 }
1508         }
1509
1510         return NULL;
1511 }
1512
1513 static struct yaffs_cache *yaffs_grab_chunk_cache(struct yaffs_dev *dev)
1514 {
1515         struct yaffs_cache *cache;
1516         struct yaffs_obj *the_obj;
1517         int usage;
1518         int i;
1519         int pushout;
1520
1521         if (dev->param.n_caches > 0) {
1522                 /* Try find a non-dirty one... */
1523
1524                 cache = yaffs_grab_chunk_worker(dev);
1525
1526                 if (!cache) {
1527                         /* They were all dirty, find the last recently used object and flush
1528                          * its cache, then  find again.
1529                          * NB what's here is not very accurate, we actually flush the object
1530                          * the last recently used page.
1531                          */
1532
1533                         /* With locking we can't assume we can use entry zero */
1534
1535                         the_obj = NULL;
1536                         usage = -1;
1537                         cache = NULL;
1538                         pushout = -1;
1539
1540                         for (i = 0; i < dev->param.n_caches; i++) {
1541                                 if (dev->cache[i].object &&
1542                                     !dev->cache[i].locked &&
1543                                     (dev->cache[i].last_use < usage
1544                                      || !cache)) {
1545                                         usage = dev->cache[i].last_use;
1546                                         the_obj = dev->cache[i].object;
1547                                         cache = &dev->cache[i];
1548                                         pushout = i;
1549                                 }
1550                         }
1551
1552                         if (!cache || cache->dirty) {
1553                                 /* Flush and try again */
1554                                 yaffs_flush_file_cache(the_obj);
1555                                 cache = yaffs_grab_chunk_worker(dev);
1556                         }
1557
1558                 }
1559                 return cache;
1560         } else {
1561                 return NULL;
1562         }
1563 }
1564
1565 /* Find a cached chunk */
1566 static struct yaffs_cache *yaffs_find_chunk_cache(const struct yaffs_obj *obj,
1567                                                   int chunk_id)
1568 {
1569         struct yaffs_dev *dev = obj->my_dev;
1570         int i;
1571         if (dev->param.n_caches > 0) {
1572                 for (i = 0; i < dev->param.n_caches; i++) {
1573                         if (dev->cache[i].object == obj &&
1574                             dev->cache[i].chunk_id == chunk_id) {
1575                                 dev->cache_hits++;
1576
1577                                 return &dev->cache[i];
1578                         }
1579                 }
1580         }
1581         return NULL;
1582 }
1583
1584 /* Mark the chunk for the least recently used algorithym */
1585 static void yaffs_use_cache(struct yaffs_dev *dev, struct yaffs_cache *cache,
1586                             int is_write)
1587 {
1588
1589         if (dev->param.n_caches > 0) {
1590                 if (dev->cache_last_use < 0 || dev->cache_last_use > 100000000) {
1591                         /* Reset the cache usages */
1592                         int i;
1593                         for (i = 1; i < dev->param.n_caches; i++)
1594                                 dev->cache[i].last_use = 0;
1595
1596                         dev->cache_last_use = 0;
1597                 }
1598
1599                 dev->cache_last_use++;
1600
1601                 cache->last_use = dev->cache_last_use;
1602
1603                 if (is_write)
1604                         cache->dirty = 1;
1605         }
1606 }
1607
1608 /* Invalidate a single cache page.
1609  * Do this when a whole page gets written,
1610  * ie the short cache for this page is no longer valid.
1611  */
1612 static void yaffs_invalidate_chunk_cache(struct yaffs_obj *object, int chunk_id)
1613 {
1614         if (object->my_dev->param.n_caches > 0) {
1615                 struct yaffs_cache *cache =
1616                     yaffs_find_chunk_cache(object, chunk_id);
1617
1618                 if (cache)
1619                         cache->object = NULL;
1620         }
1621 }
1622
1623 /* Invalidate all the cache pages associated with this object
1624  * Do this whenever ther file is deleted or resized.
1625  */
1626 static void yaffs_invalidate_whole_cache(struct yaffs_obj *in)
1627 {
1628         int i;
1629         struct yaffs_dev *dev = in->my_dev;
1630
1631         if (dev->param.n_caches > 0) {
1632                 /* Invalidate it. */
1633                 for (i = 0; i < dev->param.n_caches; i++) {
1634                         if (dev->cache[i].object == in)
1635                                 dev->cache[i].object = NULL;
1636                 }
1637         }
1638 }
1639
1640 static void yaffs_unhash_obj(struct yaffs_obj *obj)
1641 {
1642         int bucket;
1643         struct yaffs_dev *dev = obj->my_dev;
1644
1645         /* If it is still linked into the bucket list, free from the list */
1646         if (!list_empty(&obj->hash_link)) {
1647                 list_del_init(&obj->hash_link);
1648                 bucket = yaffs_hash_fn(obj->obj_id);
1649                 dev->obj_bucket[bucket].count--;
1650         }
1651 }
1652
1653 /*  FreeObject frees up a Object and puts it back on the free list */
1654 static void yaffs_free_obj(struct yaffs_obj *obj)
1655 {
1656         struct yaffs_dev *dev = obj->my_dev;
1657
1658         yaffs_trace(YAFFS_TRACE_OS, "FreeObject %p inode %p",
1659                 obj, obj->my_inode);
1660
1661         if (!obj)
1662                 YBUG();
1663         if (obj->parent)
1664                 YBUG();
1665         if (!list_empty(&obj->siblings))
1666                 YBUG();
1667
1668         if (obj->my_inode) {
1669                 /* We're still hooked up to a cached inode.
1670                  * Don't delete now, but mark for later deletion
1671                  */
1672                 obj->defered_free = 1;
1673                 return;
1674         }
1675
1676         yaffs_unhash_obj(obj);
1677
1678         yaffs_free_raw_obj(dev, obj);
1679         dev->n_obj--;
1680         dev->checkpoint_blocks_required = 0;    /* force recalculation */
1681 }
1682
1683 void yaffs_handle_defered_free(struct yaffs_obj *obj)
1684 {
1685         if (obj->defered_free)
1686                 yaffs_free_obj(obj);
1687 }
1688
1689 static int yaffs_generic_obj_del(struct yaffs_obj *in)
1690 {
1691
1692         /* First off, invalidate the file's data in the cache, without flushing. */
1693         yaffs_invalidate_whole_cache(in);
1694
1695         if (in->my_dev->param.is_yaffs2 && (in->parent != in->my_dev->del_dir)) {
1696                 /* Move to the unlinked directory so we have a record that it was deleted. */
1697                 yaffs_change_obj_name(in, in->my_dev->del_dir, _Y("deleted"), 0,
1698                                       0);
1699
1700         }
1701
1702         yaffs_remove_obj_from_dir(in);
1703         yaffs_chunk_del(in->my_dev, in->hdr_chunk, 1, __LINE__);
1704         in->hdr_chunk = 0;
1705
1706         yaffs_free_obj(in);
1707         return YAFFS_OK;
1708
1709 }
1710
1711 static void yaffs_soft_del_file(struct yaffs_obj *obj)
1712 {
1713         if (obj->deleted &&
1714             obj->variant_type == YAFFS_OBJECT_TYPE_FILE && !obj->soft_del) {
1715                 if (obj->n_data_chunks <= 0) {
1716                         /* Empty file with no duplicate object headers,
1717                          * just delete it immediately */
1718                         yaffs_free_tnode(obj->my_dev,
1719                                          obj->variant.file_variant.top);
1720                         obj->variant.file_variant.top = NULL;
1721                         yaffs_trace(YAFFS_TRACE_TRACING,
1722                                 "yaffs: Deleting empty file %d",
1723                                 obj->obj_id);
1724                         yaffs_generic_obj_del(obj);
1725                 } else {
1726                         yaffs_soft_del_worker(obj,
1727                                               obj->variant.file_variant.top,
1728                                               obj->variant.
1729                                               file_variant.top_level, 0);
1730                         obj->soft_del = 1;
1731                 }
1732         }
1733 }
1734
1735 /* Pruning removes any part of the file structure tree that is beyond the
1736  * bounds of the file (ie that does not point to chunks).
1737  *
1738  * A file should only get pruned when its size is reduced.
1739  *
1740  * Before pruning, the chunks must be pulled from the tree and the
1741  * level 0 tnode entries must be zeroed out.
1742  * Could also use this for file deletion, but that's probably better handled
1743  * by a special case.
1744  *
1745  * This function is recursive. For levels > 0 the function is called again on
1746  * any sub-tree. For level == 0 we just check if the sub-tree has data.
1747  * If there is no data in a subtree then it is pruned.
1748  */
1749
1750 static struct yaffs_tnode *yaffs_prune_worker(struct yaffs_dev *dev,
1751                                               struct yaffs_tnode *tn, u32 level,
1752                                               int del0)
1753 {
1754         int i;
1755         int has_data;
1756
1757         if (tn) {
1758                 has_data = 0;
1759
1760                 if (level > 0) {
1761                         for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1762                                 if (tn->internal[i]) {
1763                                         tn->internal[i] =
1764                                             yaffs_prune_worker(dev,
1765                                                                tn->internal[i],
1766                                                                level - 1,
1767                                                                (i ==
1768                                                                 0) ? del0 : 1);
1769                                 }
1770
1771                                 if (tn->internal[i])
1772                                         has_data++;
1773                         }
1774                 } else {
1775                         int tnode_size_u32 = dev->tnode_size / sizeof(u32);
1776                         u32 *map = (u32 *) tn;
1777
1778                         for (i = 0; !has_data && i < tnode_size_u32; i++) {
1779                                 if (map[i])
1780                                         has_data++;
1781                         }
1782                 }
1783
1784                 if (has_data == 0 && del0) {
1785                         /* Free and return NULL */
1786
1787                         yaffs_free_tnode(dev, tn);
1788                         tn = NULL;
1789                 }
1790
1791         }
1792
1793         return tn;
1794
1795 }
1796
1797 static int yaffs_prune_tree(struct yaffs_dev *dev,
1798                             struct yaffs_file_var *file_struct)
1799 {
1800         int i;
1801         int has_data;
1802         int done = 0;
1803         struct yaffs_tnode *tn;
1804
1805         if (file_struct->top_level > 0) {
1806                 file_struct->top =
1807                     yaffs_prune_worker(dev, file_struct->top,
1808                                        file_struct->top_level, 0);
1809
1810                 /* Now we have a tree with all the non-zero branches NULL but the height
1811                  * is the same as it was.
1812                  * Let's see if we can trim internal tnodes to shorten the tree.
1813                  * We can do this if only the 0th element in the tnode is in use
1814                  * (ie all the non-zero are NULL)
1815                  */
1816
1817                 while (file_struct->top_level && !done) {
1818                         tn = file_struct->top;
1819
1820                         has_data = 0;
1821                         for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1822                                 if (tn->internal[i])
1823                                         has_data++;
1824                         }
1825
1826                         if (!has_data) {
1827                                 file_struct->top = tn->internal[0];
1828                                 file_struct->top_level--;
1829                                 yaffs_free_tnode(dev, tn);
1830                         } else {
1831                                 done = 1;
1832                         }
1833                 }
1834         }
1835
1836         return YAFFS_OK;
1837 }
1838
1839 /*-------------------- End of File Structure functions.-------------------*/
1840
1841 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1842 static struct yaffs_obj *yaffs_alloc_empty_obj(struct yaffs_dev *dev)
1843 {
1844         struct yaffs_obj *obj = yaffs_alloc_raw_obj(dev);
1845
1846         if (obj) {
1847                 dev->n_obj++;
1848
1849                 /* Now sweeten it up... */
1850
1851                 memset(obj, 0, sizeof(struct yaffs_obj));
1852                 obj->being_created = 1;
1853
1854                 obj->my_dev = dev;
1855                 obj->hdr_chunk = 0;
1856                 obj->variant_type = YAFFS_OBJECT_TYPE_UNKNOWN;
1857                 INIT_LIST_HEAD(&(obj->hard_links));
1858                 INIT_LIST_HEAD(&(obj->hash_link));
1859                 INIT_LIST_HEAD(&obj->siblings);
1860
1861                 /* Now make the directory sane */
1862                 if (dev->root_dir) {
1863                         obj->parent = dev->root_dir;
1864                         list_add(&(obj->siblings),
1865                                  &dev->root_dir->variant.dir_variant.children);
1866                 }
1867
1868                 /* Add it to the lost and found directory.
1869                  * NB Can't put root or lost-n-found in lost-n-found so
1870                  * check if lost-n-found exists first
1871                  */
1872                 if (dev->lost_n_found)
1873                         yaffs_add_obj_to_dir(dev->lost_n_found, obj);
1874
1875                 obj->being_created = 0;
1876         }
1877
1878         dev->checkpoint_blocks_required = 0;    /* force recalculation */
1879
1880         return obj;
1881 }
1882
1883 static int yaffs_find_nice_bucket(struct yaffs_dev *dev)
1884 {
1885         int i;
1886         int l = 999;
1887         int lowest = 999999;
1888
1889         /* Search for the shortest list or one that
1890          * isn't too long.
1891          */
1892
1893         for (i = 0; i < 10 && lowest > 4; i++) {
1894                 dev->bucket_finder++;
1895                 dev->bucket_finder %= YAFFS_NOBJECT_BUCKETS;
1896                 if (dev->obj_bucket[dev->bucket_finder].count < lowest) {
1897                         lowest = dev->obj_bucket[dev->bucket_finder].count;
1898                         l = dev->bucket_finder;
1899                 }
1900
1901         }
1902
1903         return l;
1904 }
1905
1906 static int yaffs_new_obj_id(struct yaffs_dev *dev)
1907 {
1908         int bucket = yaffs_find_nice_bucket(dev);
1909
1910         /* Now find an object value that has not already been taken
1911          * by scanning the list.
1912          */
1913
1914         int found = 0;
1915         struct list_head *i;
1916
1917         u32 n = (u32) bucket;
1918
1919         /* yaffs_check_obj_hash_sane();  */
1920
1921         while (!found) {
1922                 found = 1;
1923                 n += YAFFS_NOBJECT_BUCKETS;
1924                 if (1 || dev->obj_bucket[bucket].count > 0) {
1925                         list_for_each(i, &dev->obj_bucket[bucket].list) {
1926                                 /* If there is already one in the list */
1927                                 if (i && list_entry(i, struct yaffs_obj,
1928                                                     hash_link)->obj_id == n) {
1929                                         found = 0;
1930                                 }
1931                         }
1932                 }
1933         }
1934
1935         return n;
1936 }
1937
1938 static void yaffs_hash_obj(struct yaffs_obj *in)
1939 {
1940         int bucket = yaffs_hash_fn(in->obj_id);
1941         struct yaffs_dev *dev = in->my_dev;
1942
1943         list_add(&in->hash_link, &dev->obj_bucket[bucket].list);
1944         dev->obj_bucket[bucket].count++;
1945 }
1946
1947 struct yaffs_obj *yaffs_find_by_number(struct yaffs_dev *dev, u32 number)
1948 {
1949         int bucket = yaffs_hash_fn(number);
1950         struct list_head *i;
1951         struct yaffs_obj *in;
1952
1953         list_for_each(i, &dev->obj_bucket[bucket].list) {
1954                 /* Look if it is in the list */
1955                 if (i) {
1956                         in = list_entry(i, struct yaffs_obj, hash_link);
1957                         if (in->obj_id == number) {
1958
1959                                 /* Don't tell the VFS about this one if it is defered free */
1960                                 if (in->defered_free)
1961                                         return NULL;
1962
1963                                 return in;
1964                         }
1965                 }
1966         }
1967
1968         return NULL;
1969 }
1970
1971 struct yaffs_obj *yaffs_new_obj(struct yaffs_dev *dev, int number,
1972                                 enum yaffs_obj_type type)
1973 {
1974         struct yaffs_obj *the_obj = NULL;
1975         struct yaffs_tnode *tn = NULL;
1976
1977         if (number < 0)
1978                 number = yaffs_new_obj_id(dev);
1979
1980         if (type == YAFFS_OBJECT_TYPE_FILE) {
1981                 tn = yaffs_get_tnode(dev);
1982                 if (!tn)
1983                         return NULL;
1984         }
1985
1986         the_obj = yaffs_alloc_empty_obj(dev);
1987         if (!the_obj) {
1988                 if (tn)
1989                         yaffs_free_tnode(dev, tn);
1990                 return NULL;
1991         }
1992
1993         if (the_obj) {
1994                 the_obj->fake = 0;
1995                 the_obj->rename_allowed = 1;
1996                 the_obj->unlink_allowed = 1;
1997                 the_obj->obj_id = number;
1998                 yaffs_hash_obj(the_obj);
1999                 the_obj->variant_type = type;
2000                 yaffs_load_current_time(the_obj, 1, 1);
2001
2002                 switch (type) {
2003                 case YAFFS_OBJECT_TYPE_FILE:
2004                         the_obj->variant.file_variant.file_size = 0;
2005                         the_obj->variant.file_variant.scanned_size = 0;
2006                         the_obj->variant.file_variant.shrink_size = ~0; /* max */
2007                         the_obj->variant.file_variant.top_level = 0;
2008                         the_obj->variant.file_variant.top = tn;
2009                         break;
2010                 case YAFFS_OBJECT_TYPE_DIRECTORY:
2011                         INIT_LIST_HEAD(&the_obj->variant.dir_variant.children);
2012                         INIT_LIST_HEAD(&the_obj->variant.dir_variant.dirty);
2013                         break;
2014                 case YAFFS_OBJECT_TYPE_SYMLINK:
2015                 case YAFFS_OBJECT_TYPE_HARDLINK:
2016                 case YAFFS_OBJECT_TYPE_SPECIAL:
2017                         /* No action required */
2018                         break;
2019                 case YAFFS_OBJECT_TYPE_UNKNOWN:
2020                         /* todo this should not happen */
2021                         break;
2022                 }
2023         }
2024
2025         return the_obj;
2026 }
2027
2028 static struct yaffs_obj *yaffs_create_fake_dir(struct yaffs_dev *dev,
2029                                                int number, u32 mode)
2030 {
2031
2032         struct yaffs_obj *obj =
2033             yaffs_new_obj(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
2034         if (obj) {
2035                 obj->fake = 1;  /* it is fake so it might have no NAND presence... */
2036                 obj->rename_allowed = 0;        /* ... and we're not allowed to rename it... */
2037                 obj->unlink_allowed = 0;        /* ... or unlink it */
2038                 obj->deleted = 0;
2039                 obj->unlinked = 0;
2040                 obj->yst_mode = mode;
2041                 obj->my_dev = dev;
2042                 obj->hdr_chunk = 0;     /* Not a valid chunk. */
2043         }
2044
2045         return obj;
2046
2047 }
2048
2049
2050 static void yaffs_init_tnodes_and_objs(struct yaffs_dev *dev)
2051 {
2052         int i;
2053
2054         dev->n_obj = 0;
2055         dev->n_tnodes = 0;
2056
2057         yaffs_init_raw_tnodes_and_objs(dev);
2058
2059         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
2060                 INIT_LIST_HEAD(&dev->obj_bucket[i].list);
2061                 dev->obj_bucket[i].count = 0;
2062         }
2063 }
2064
2065 struct yaffs_obj *yaffs_find_or_create_by_number(struct yaffs_dev *dev,
2066                                                  int number,
2067                                                  enum yaffs_obj_type type)
2068 {
2069         struct yaffs_obj *the_obj = NULL;
2070
2071         if (number > 0)
2072                 the_obj = yaffs_find_by_number(dev, number);
2073
2074         if (!the_obj)
2075                 the_obj = yaffs_new_obj(dev, number, type);
2076
2077         return the_obj;
2078
2079 }
2080
2081 YCHAR *yaffs_clone_str(const YCHAR * str)
2082 {
2083         YCHAR *new_str = NULL;
2084         int len;
2085
2086         if (!str)
2087                 str = _Y("");
2088
2089         len = strnlen(str, YAFFS_MAX_ALIAS_LENGTH);
2090         new_str = kmalloc((len + 1) * sizeof(YCHAR), GFP_NOFS);
2091         if (new_str) {
2092                 strncpy(new_str, str, len);
2093                 new_str[len] = 0;
2094         }
2095         return new_str;
2096
2097 }
2098 /*
2099  *yaffs_update_parent() handles fixing a directories mtime and ctime when a new
2100  * link (ie. name) is created or deleted in the directory.
2101  *
2102  * ie.
2103  *   create dir/a : update dir's mtime/ctime
2104  *   rm dir/a:   update dir's mtime/ctime
2105  *   modify dir/a: don't update dir's mtimme/ctime
2106  *
2107  * This can be handled immediately or defered. Defering helps reduce the number
2108  * of updates when many files in a directory are changed within a brief period.
2109  *
2110  * If the directory updating is defered then yaffs_update_dirty_dirs must be
2111  * called periodically.
2112  */
2113
2114 static void yaffs_update_parent(struct yaffs_obj *obj)
2115 {
2116         struct yaffs_dev *dev;
2117         if (!obj)
2118                 return;
2119         dev = obj->my_dev;
2120         obj->dirty = 1;
2121         yaffs_load_current_time(obj, 0, 1);
2122         if (dev->param.defered_dir_update) {
2123                 struct list_head *link = &obj->variant.dir_variant.dirty;
2124
2125                 if (list_empty(link)) {
2126                         list_add(link, &dev->dirty_dirs);
2127                         yaffs_trace(YAFFS_TRACE_BACKGROUND,
2128                           "Added object %d to dirty directories",
2129                            obj->obj_id);
2130                 }
2131
2132         } else {
2133                 yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
2134         }
2135 }
2136
2137 void yaffs_update_dirty_dirs(struct yaffs_dev *dev)
2138 {
2139         struct list_head *link;
2140         struct yaffs_obj *obj;
2141         struct yaffs_dir_var *d_s;
2142         union yaffs_obj_var *o_v;
2143
2144         yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update dirty directories");
2145
2146         while (!list_empty(&dev->dirty_dirs)) {
2147                 link = dev->dirty_dirs.next;
2148                 list_del_init(link);
2149
2150                 d_s = list_entry(link, struct yaffs_dir_var, dirty);
2151                 o_v = list_entry(d_s, union yaffs_obj_var, dir_variant);
2152                 obj = list_entry(o_v, struct yaffs_obj, variant);
2153
2154                 yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update directory %d",
2155                         obj->obj_id);
2156
2157                 if (obj->dirty)
2158                         yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
2159         }
2160 }
2161
2162 /*
2163  * Mknod (create) a new object.
2164  * equiv_obj only has meaning for a hard link;
2165  * alias_str only has meaning for a symlink.
2166  * rdev only has meaning for devices (a subset of special objects)
2167  */
2168
2169 static struct yaffs_obj *yaffs_create_obj(enum yaffs_obj_type type,
2170                                           struct yaffs_obj *parent,
2171                                           const YCHAR * name,
2172                                           u32 mode,
2173                                           u32 uid,
2174                                           u32 gid,
2175                                           struct yaffs_obj *equiv_obj,
2176                                           const YCHAR * alias_str, u32 rdev)
2177 {
2178         struct yaffs_obj *in;
2179         YCHAR *str = NULL;
2180
2181         struct yaffs_dev *dev = parent->my_dev;
2182
2183         /* Check if the entry exists. If it does then fail the call since we don't want a dup. */
2184         if (yaffs_find_by_name(parent, name))
2185                 return NULL;
2186
2187         if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
2188                 str = yaffs_clone_str(alias_str);
2189                 if (!str)
2190                         return NULL;
2191         }
2192
2193         in = yaffs_new_obj(dev, -1, type);
2194
2195         if (!in) {
2196                 if (str)
2197                         kfree(str);
2198                 return NULL;
2199         }
2200
2201         if (in) {
2202                 in->hdr_chunk = 0;
2203                 in->valid = 1;
2204                 in->variant_type = type;
2205
2206                 in->yst_mode = mode;
2207
2208                 yaffs_attribs_init(in, gid, uid, rdev);
2209
2210                 in->n_data_chunks = 0;
2211
2212                 yaffs_set_obj_name(in, name);
2213                 in->dirty = 1;
2214
2215                 yaffs_add_obj_to_dir(parent, in);
2216
2217                 in->my_dev = parent->my_dev;
2218
2219                 switch (type) {
2220                 case YAFFS_OBJECT_TYPE_SYMLINK:
2221                         in->variant.symlink_variant.alias = str;
2222                         break;
2223                 case YAFFS_OBJECT_TYPE_HARDLINK:
2224                         in->variant.hardlink_variant.equiv_obj = equiv_obj;
2225                         in->variant.hardlink_variant.equiv_id =
2226                             equiv_obj->obj_id;
2227                         list_add(&in->hard_links, &equiv_obj->hard_links);
2228                         break;
2229                 case YAFFS_OBJECT_TYPE_FILE:
2230                 case YAFFS_OBJECT_TYPE_DIRECTORY:
2231                 case YAFFS_OBJECT_TYPE_SPECIAL:
2232                 case YAFFS_OBJECT_TYPE_UNKNOWN:
2233                         /* do nothing */
2234                         break;
2235                 }
2236
2237                 if (yaffs_update_oh(in, name, 0, 0, 0, NULL) < 0) {
2238                         /* Could not create the object header, fail the creation */
2239                         yaffs_del_obj(in);
2240                         in = NULL;
2241                 }
2242
2243                 yaffs_update_parent(parent);
2244         }
2245
2246         return in;
2247 }
2248
2249 struct yaffs_obj *yaffs_create_file(struct yaffs_obj *parent,
2250                                     const YCHAR * name, u32 mode, u32 uid,
2251                                     u32 gid)
2252 {
2253         return yaffs_create_obj(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
2254                                 uid, gid, NULL, NULL, 0);
2255 }
2256
2257 struct yaffs_obj *yaffs_create_dir(struct yaffs_obj *parent, const YCHAR * name,
2258                                    u32 mode, u32 uid, u32 gid)
2259 {
2260         return yaffs_create_obj(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
2261                                 mode, uid, gid, NULL, NULL, 0);
2262 }
2263
2264 struct yaffs_obj *yaffs_create_special(struct yaffs_obj *parent,
2265                                        const YCHAR * name, u32 mode, u32 uid,
2266                                        u32 gid, u32 rdev)
2267 {
2268         return yaffs_create_obj(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
2269                                 uid, gid, NULL, NULL, rdev);
2270 }
2271
2272 struct yaffs_obj *yaffs_create_symlink(struct yaffs_obj *parent,
2273                                        const YCHAR * name, u32 mode, u32 uid,
2274                                        u32 gid, const YCHAR * alias)
2275 {
2276         return yaffs_create_obj(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
2277                                 uid, gid, NULL, alias, 0);
2278 }
2279
2280 /* yaffs_link_obj returns the object id of the equivalent object.*/
2281 struct yaffs_obj *yaffs_link_obj(struct yaffs_obj *parent, const YCHAR * name,
2282                                  struct yaffs_obj *equiv_obj)
2283 {
2284         /* Get the real object in case we were fed a hard link as an equivalent object */
2285         equiv_obj = yaffs_get_equivalent_obj(equiv_obj);
2286
2287         if (yaffs_create_obj
2288             (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
2289              equiv_obj, NULL, 0)) {
2290                 return equiv_obj;
2291         } else {
2292                 return NULL;
2293         }
2294
2295 }
2296
2297
2298
2299 /*------------------------- Block Management and Page Allocation ----------------*/
2300
2301 static int yaffs_init_blocks(struct yaffs_dev *dev)
2302 {
2303         int n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
2304
2305         dev->block_info = NULL;
2306         dev->chunk_bits = NULL;
2307
2308         dev->alloc_block = -1;  /* force it to get a new one */
2309
2310         /* If the first allocation strategy fails, thry the alternate one */
2311         dev->block_info =
2312                 kmalloc(n_blocks * sizeof(struct yaffs_block_info), GFP_NOFS);
2313         if (!dev->block_info) {
2314                 dev->block_info =
2315                     vmalloc(n_blocks * sizeof(struct yaffs_block_info));
2316                 dev->block_info_alt = 1;
2317         } else {
2318                 dev->block_info_alt = 0;
2319         }
2320
2321         if (dev->block_info) {
2322                 /* Set up dynamic blockinfo stuff. Round up bytes. */
2323                 dev->chunk_bit_stride = (dev->param.chunks_per_block + 7) / 8;
2324                 dev->chunk_bits =
2325                         kmalloc(dev->chunk_bit_stride * n_blocks, GFP_NOFS);
2326                 if (!dev->chunk_bits) {
2327                         dev->chunk_bits =
2328                             vmalloc(dev->chunk_bit_stride * n_blocks);
2329                         dev->chunk_bits_alt = 1;
2330                 } else {
2331                         dev->chunk_bits_alt = 0;
2332                 }
2333         }
2334
2335         if (dev->block_info && dev->chunk_bits) {
2336                 memset(dev->block_info, 0,
2337                        n_blocks * sizeof(struct yaffs_block_info));
2338                 memset(dev->chunk_bits, 0, dev->chunk_bit_stride * n_blocks);
2339                 return YAFFS_OK;
2340         }
2341
2342         return YAFFS_FAIL;
2343 }
2344
2345 static void yaffs_deinit_blocks(struct yaffs_dev *dev)
2346 {
2347         if (dev->block_info_alt && dev->block_info)
2348                 vfree(dev->block_info);
2349         else if (dev->block_info)
2350                 kfree(dev->block_info);
2351
2352         dev->block_info_alt = 0;
2353
2354         dev->block_info = NULL;
2355
2356         if (dev->chunk_bits_alt && dev->chunk_bits)
2357                 vfree(dev->chunk_bits);
2358         else if (dev->chunk_bits)
2359                 kfree(dev->chunk_bits);
2360         dev->chunk_bits_alt = 0;
2361         dev->chunk_bits = NULL;
2362 }
2363
2364 void yaffs_block_became_dirty(struct yaffs_dev *dev, int block_no)
2365 {
2366         struct yaffs_block_info *bi = yaffs_get_block_info(dev, block_no);
2367
2368         int erased_ok = 0;
2369
2370         /* If the block is still healthy erase it and mark as clean.
2371          * If the block has had a data failure, then retire it.
2372          */
2373
2374         yaffs_trace(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
2375                 "yaffs_block_became_dirty block %d state %d %s",
2376                 block_no, bi->block_state,
2377                 (bi->needs_retiring) ? "needs retiring" : "");
2378
2379         yaffs2_clear_oldest_dirty_seq(dev, bi);
2380
2381         bi->block_state = YAFFS_BLOCK_STATE_DIRTY;
2382
2383         /* If this is the block being garbage collected then stop gc'ing this block */
2384         if (block_no == dev->gc_block)
2385                 dev->gc_block = 0;
2386
2387         /* If this block is currently the best candidate for gc then drop as a candidate */
2388         if (block_no == dev->gc_dirtiest) {
2389                 dev->gc_dirtiest = 0;
2390                 dev->gc_pages_in_use = 0;
2391         }
2392
2393         if (!bi->needs_retiring) {
2394                 yaffs2_checkpt_invalidate(dev);
2395                 erased_ok = yaffs_erase_block(dev, block_no);
2396                 if (!erased_ok) {
2397                         dev->n_erase_failures++;
2398                         yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2399                           "**>> Erasure failed %d", block_no);
2400                 }
2401         }
2402
2403         if (erased_ok &&
2404             ((yaffs_trace_mask & YAFFS_TRACE_ERASE)
2405              || !yaffs_skip_verification(dev))) {
2406                 int i;
2407                 for (i = 0; i < dev->param.chunks_per_block; i++) {
2408                         if (!yaffs_check_chunk_erased
2409                             (dev, block_no * dev->param.chunks_per_block + i)) {
2410                                 yaffs_trace(YAFFS_TRACE_ERROR,
2411                                         ">>Block %d erasure supposedly OK, but chunk %d not erased",
2412                                         block_no, i);
2413                         }
2414                 }
2415         }
2416
2417         if (erased_ok) {
2418                 /* Clean it up... */
2419                 bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
2420                 bi->seq_number = 0;
2421                 dev->n_erased_blocks++;
2422                 bi->pages_in_use = 0;
2423                 bi->soft_del_pages = 0;
2424                 bi->has_shrink_hdr = 0;
2425                 bi->skip_erased_check = 1;      /* Clean, so no need to check */
2426                 bi->gc_prioritise = 0;
2427                 yaffs_clear_chunk_bits(dev, block_no);
2428
2429                 yaffs_trace(YAFFS_TRACE_ERASE,
2430                         "Erased block %d", block_no);
2431         } else {
2432                 /* We lost a block of free space */
2433                 dev->n_free_chunks -= dev->param.chunks_per_block;
2434                 yaffs_retire_block(dev, block_no);
2435                 yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2436                         "**>> Block %d retired", block_no);
2437         }
2438 }
2439
2440
2441
2442 static int yaffs_gc_block(struct yaffs_dev *dev, int block, int whole_block)
2443 {
2444         int old_chunk;
2445         int new_chunk;
2446         int mark_flash;
2447         int ret_val = YAFFS_OK;
2448         int i;
2449         int is_checkpt_block;
2450         int matching_chunk;
2451         int max_copies;
2452
2453         int chunks_before = yaffs_get_erased_chunks(dev);
2454         int chunks_after;
2455
2456         struct yaffs_ext_tags tags;
2457
2458         struct yaffs_block_info *bi = yaffs_get_block_info(dev, block);
2459
2460         struct yaffs_obj *object;
2461
2462         is_checkpt_block = (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT);
2463
2464         yaffs_trace(YAFFS_TRACE_TRACING,
2465                 "Collecting block %d, in use %d, shrink %d, whole_block %d",
2466                 block, bi->pages_in_use, bi->has_shrink_hdr,
2467                 whole_block);
2468
2469         /*yaffs_verify_free_chunks(dev); */
2470
2471         if (bi->block_state == YAFFS_BLOCK_STATE_FULL)
2472                 bi->block_state = YAFFS_BLOCK_STATE_COLLECTING;
2473
2474         bi->has_shrink_hdr = 0; /* clear the flag so that the block can erase */
2475
2476         dev->gc_disable = 1;
2477
2478         if (is_checkpt_block || !yaffs_still_some_chunks(dev, block)) {
2479                 yaffs_trace(YAFFS_TRACE_TRACING,
2480                         "Collecting block %d that has no chunks in use",
2481                         block);
2482                 yaffs_block_became_dirty(dev, block);
2483         } else {
2484
2485                 u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
2486
2487                 yaffs_verify_blk(dev, bi, block);
2488
2489                 max_copies = (whole_block) ? dev->param.chunks_per_block : 5;
2490                 old_chunk = block * dev->param.chunks_per_block + dev->gc_chunk;
2491
2492                 for ( /* init already done */ ;
2493                      ret_val == YAFFS_OK &&
2494                      dev->gc_chunk < dev->param.chunks_per_block &&
2495                      (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) &&
2496                      max_copies > 0; dev->gc_chunk++, old_chunk++) {
2497                         if (yaffs_check_chunk_bit(dev, block, dev->gc_chunk)) {
2498
2499                                 /* This page is in use and might need to be copied off */
2500
2501                                 max_copies--;
2502
2503                                 mark_flash = 1;
2504
2505                                 yaffs_init_tags(&tags);
2506
2507                                 yaffs_rd_chunk_tags_nand(dev, old_chunk,
2508                                                          buffer, &tags);
2509
2510                                 object = yaffs_find_by_number(dev, tags.obj_id);
2511
2512                                 yaffs_trace(YAFFS_TRACE_GC_DETAIL,
2513                                         "Collecting chunk in block %d, %d %d %d ",
2514                                         dev->gc_chunk, tags.obj_id,
2515                                         tags.chunk_id, tags.n_bytes);
2516
2517                                 if (object && !yaffs_skip_verification(dev)) {
2518                                         if (tags.chunk_id == 0)
2519                                                 matching_chunk =
2520                                                     object->hdr_chunk;
2521                                         else if (object->soft_del)
2522                                                 matching_chunk = old_chunk;     /* Defeat the test */
2523                                         else
2524                                                 matching_chunk =
2525                                                     yaffs_find_chunk_in_file
2526                                                     (object, tags.chunk_id,
2527                                                      NULL);
2528
2529                                         if (old_chunk != matching_chunk)
2530                                                 yaffs_trace(YAFFS_TRACE_ERROR,
2531                                                         "gc: page in gc mismatch: %d %d %d %d",
2532                                                         old_chunk,
2533                                                         matching_chunk,
2534                                                         tags.obj_id,
2535                                                         tags.chunk_id);
2536
2537                                 }
2538
2539                                 if (!object) {
2540                                         yaffs_trace(YAFFS_TRACE_ERROR,
2541                                                 "page %d in gc has no object: %d %d %d ",
2542                                                 old_chunk,
2543                                                 tags.obj_id, tags.chunk_id,
2544                                                 tags.n_bytes);
2545                                 }
2546
2547                                 if (object &&
2548                                     object->deleted &&
2549                                     object->soft_del && tags.chunk_id != 0) {
2550                                         /* Data chunk in a soft deleted file, throw it away
2551                                          * It's a soft deleted data chunk,
2552                                          * No need to copy this, just forget about it and
2553                                          * fix up the object.
2554                                          */
2555
2556                                         /* Free chunks already includes softdeleted chunks.
2557                                          * How ever this chunk is going to soon be really deleted
2558                                          * which will increment free chunks.
2559                                          * We have to decrement free chunks so this works out properly.
2560                                          */
2561                                         dev->n_free_chunks--;
2562                                         bi->soft_del_pages--;
2563
2564                                         object->n_data_chunks--;
2565
2566                                         if (object->n_data_chunks <= 0) {
2567                                                 /* remeber to clean up the object */
2568                                                 dev->gc_cleanup_list[dev->
2569                                                                      n_clean_ups]
2570                                                     = tags.obj_id;
2571                                                 dev->n_clean_ups++;
2572                                         }
2573                                         mark_flash = 0;
2574                                 } else if (0) {
2575                                         /* Todo object && object->deleted && object->n_data_chunks == 0 */
2576                                         /* Deleted object header with no data chunks.
2577                                          * Can be discarded and the file deleted.
2578                                          */
2579                                         object->hdr_chunk = 0;
2580                                         yaffs_free_tnode(object->my_dev,
2581                                                          object->
2582                                                          variant.file_variant.
2583                                                          top);
2584                                         object->variant.file_variant.top = NULL;
2585                                         yaffs_generic_obj_del(object);
2586
2587                                 } else if (object) {
2588                                         /* It's either a data chunk in a live file or
2589                                          * an ObjectHeader, so we're interested in it.
2590                                          * NB Need to keep the ObjectHeaders of deleted files
2591                                          * until the whole file has been deleted off
2592                                          */
2593                                         tags.serial_number++;
2594
2595                                         dev->n_gc_copies++;
2596
2597                                         if (tags.chunk_id == 0) {
2598                                                 /* It is an object Id,
2599                                                  * We need to nuke the shrinkheader flags first
2600                                                  * Also need to clean up shadowing.
2601                                                  * We no longer want the shrink_header flag since its work is done
2602                                                  * and if it is left in place it will mess up scanning.
2603                                                  */
2604
2605                                                 struct yaffs_obj_hdr *oh;
2606                                                 oh = (struct yaffs_obj_hdr *)
2607                                                     buffer;
2608
2609                                                 oh->is_shrink = 0;
2610                                                 tags.extra_is_shrink = 0;
2611
2612                                                 oh->shadows_obj = 0;
2613                                                 oh->inband_shadowed_obj_id = 0;
2614                                                 tags.extra_shadows = 0;
2615
2616                                                 /* Update file size */
2617                                                 if (object->variant_type ==
2618                                                     YAFFS_OBJECT_TYPE_FILE) {
2619                                                         oh->file_size =
2620                                                             object->variant.
2621                                                             file_variant.
2622                                                             file_size;
2623                                                         tags.extra_length =
2624                                                             oh->file_size;
2625                                                 }
2626
2627                                                 yaffs_verify_oh(object, oh,
2628                                                                 &tags, 1);
2629                                                 new_chunk =
2630                                                     yaffs_write_new_chunk(dev,
2631                                                                           (u8 *)
2632                                                                           oh,
2633                                                                           &tags,
2634                                                                           1);
2635                                         } else {
2636                                                 new_chunk =
2637                                                     yaffs_write_new_chunk(dev,
2638                                                                           buffer,
2639                                                                           &tags,
2640                                                                           1);
2641                                         }
2642
2643                                         if (new_chunk < 0) {
2644                                                 ret_val = YAFFS_FAIL;
2645                                         } else {
2646
2647                                                 /* Ok, now fix up the Tnodes etc. */
2648
2649                                                 if (tags.chunk_id == 0) {
2650                                                         /* It's a header */
2651                                                         object->hdr_chunk =
2652                                                             new_chunk;
2653                                                         object->serial =
2654                                                             tags.serial_number;
2655                                                 } else {
2656                                                         /* It's a data chunk */
2657                                                         int ok;
2658                                                         ok = yaffs_put_chunk_in_file(object, tags.chunk_id, new_chunk, 0);
2659                                                 }
2660                                         }
2661                                 }
2662
2663                                 if (ret_val == YAFFS_OK)
2664                                         yaffs_chunk_del(dev, old_chunk,
2665                                                         mark_flash, __LINE__);
2666
2667                         }
2668                 }
2669
2670                 yaffs_release_temp_buffer(dev, buffer, __LINE__);
2671
2672         }
2673
2674         yaffs_verify_collected_blk(dev, bi, block);
2675
2676         if (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
2677                 /*
2678                  * The gc did not complete. Set block state back to FULL
2679                  * because checkpointing does not restore gc.
2680                  */
2681                 bi->block_state = YAFFS_BLOCK_STATE_FULL;
2682         } else {
2683                 /* The gc completed. */
2684                 /* Do any required cleanups */
2685                 for (i = 0; i < dev->n_clean_ups; i++) {
2686                         /* Time to delete the file too */
2687                         object =
2688                             yaffs_find_by_number(dev, dev->gc_cleanup_list[i]);
2689                         if (object) {
2690                                 yaffs_free_tnode(dev,
2691                                                  object->variant.
2692                                                  file_variant.top);
2693                                 object->variant.file_variant.top = NULL;
2694                                 yaffs_trace(YAFFS_TRACE_GC,
2695                                         "yaffs: About to finally delete object %d",
2696                                         object->obj_id);
2697                                 yaffs_generic_obj_del(object);
2698                                 object->my_dev->n_deleted_files--;
2699                         }
2700
2701                 }
2702
2703                 chunks_after = yaffs_get_erased_chunks(dev);
2704                 if (chunks_before >= chunks_after)
2705                         yaffs_trace(YAFFS_TRACE_GC,
2706                                 "gc did not increase free chunks before %d after %d",
2707                                 chunks_before, chunks_after);
2708                 dev->gc_block = 0;
2709                 dev->gc_chunk = 0;
2710                 dev->n_clean_ups = 0;
2711         }
2712
2713         dev->gc_disable = 0;
2714
2715         return ret_val;
2716 }
2717
2718 /*
2719  * FindBlockForgarbageCollection is used to select the dirtiest block (or close enough)
2720  * for garbage collection.
2721  */
2722
2723 static unsigned yaffs_find_gc_block(struct yaffs_dev *dev,
2724                                     int aggressive, int background)
2725 {
2726         int i;
2727         int iterations;
2728         unsigned selected = 0;
2729         int prioritised = 0;
2730         int prioritised_exist = 0;
2731         struct yaffs_block_info *bi;
2732         int threshold;
2733
2734         /* First let's see if we need to grab a prioritised block */
2735         if (dev->has_pending_prioritised_gc && !aggressive) {
2736                 dev->gc_dirtiest = 0;
2737                 bi = dev->block_info;
2738                 for (i = dev->internal_start_block;
2739                      i <= dev->internal_end_block && !selected; i++) {
2740
2741                         if (bi->gc_prioritise) {
2742                                 prioritised_exist = 1;
2743                                 if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2744                                     yaffs_block_ok_for_gc(dev, bi)) {
2745                                         selected = i;
2746                                         prioritised = 1;
2747                                 }
2748                         }
2749                         bi++;
2750                 }
2751
2752                 /*
2753                  * If there is a prioritised block and none was selected then
2754                  * this happened because there is at least one old dirty block gumming
2755                  * up the works. Let's gc the oldest dirty block.
2756                  */
2757
2758                 if (prioritised_exist &&
2759                     !selected && dev->oldest_dirty_block > 0)
2760                         selected = dev->oldest_dirty_block;
2761
2762                 if (!prioritised_exist) /* None found, so we can clear this */
2763                         dev->has_pending_prioritised_gc = 0;
2764         }
2765
2766         /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
2767          * search harder.
2768          * else (we're doing a leasurely gc), then we only bother to do this if the
2769          * block has only a few pages in use.
2770          */
2771
2772         if (!selected) {
2773                 int pages_used;
2774                 int n_blocks =
2775                     dev->internal_end_block - dev->internal_start_block + 1;
2776                 if (aggressive) {
2777                         threshold = dev->param.chunks_per_block;
2778                         iterations = n_blocks;
2779                 } else {
2780                         int max_threshold;
2781
2782                         if (background)
2783                                 max_threshold = dev->param.chunks_per_block / 2;
2784                         else
2785                                 max_threshold = dev->param.chunks_per_block / 8;
2786
2787                         if (max_threshold < YAFFS_GC_PASSIVE_THRESHOLD)
2788                                 max_threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2789
2790                         threshold = background ? (dev->gc_not_done + 2) * 2 : 0;
2791                         if (threshold < YAFFS_GC_PASSIVE_THRESHOLD)
2792                                 threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2793                         if (threshold > max_threshold)
2794                                 threshold = max_threshold;
2795
2796                         iterations = n_blocks / 16 + 1;
2797                         if (iterations > 100)
2798                                 iterations = 100;
2799                 }
2800
2801                 for (i = 0;
2802                      i < iterations &&
2803                      (dev->gc_dirtiest < 1 ||
2804                       dev->gc_pages_in_use > YAFFS_GC_GOOD_ENOUGH); i++) {
2805                         dev->gc_block_finder++;
2806                         if (dev->gc_block_finder < dev->internal_start_block ||
2807                             dev->gc_block_finder > dev->internal_end_block)
2808                                 dev->gc_block_finder =
2809                                     dev->internal_start_block;
2810
2811                         bi = yaffs_get_block_info(dev, dev->gc_block_finder);
2812
2813                         pages_used = bi->pages_in_use - bi->soft_del_pages;
2814
2815                         if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2816                             pages_used < dev->param.chunks_per_block &&
2817                             (dev->gc_dirtiest < 1
2818                              || pages_used < dev->gc_pages_in_use)
2819                             && yaffs_block_ok_for_gc(dev, bi)) {
2820                                 dev->gc_dirtiest = dev->gc_block_finder;
2821                                 dev->gc_pages_in_use = pages_used;
2822                         }
2823                 }
2824
2825                 if (dev->gc_dirtiest > 0 && dev->gc_pages_in_use <= threshold)
2826                         selected = dev->gc_dirtiest;
2827         }
2828
2829         /*
2830          * If nothing has been selected for a while, try selecting the oldest dirty
2831          * because that's gumming up the works.
2832          */
2833
2834         if (!selected && dev->param.is_yaffs2 &&
2835             dev->gc_not_done >= (background ? 10 : 20)) {
2836                 yaffs2_find_oldest_dirty_seq(dev);
2837                 if (dev->oldest_dirty_block > 0) {
2838                         selected = dev->oldest_dirty_block;
2839                         dev->gc_dirtiest = selected;
2840                         dev->oldest_dirty_gc_count++;
2841                         bi = yaffs_get_block_info(dev, selected);
2842                         dev->gc_pages_in_use =
2843                             bi->pages_in_use - bi->soft_del_pages;
2844                 } else {
2845                         dev->gc_not_done = 0;
2846                 }
2847         }
2848
2849         if (selected) {
2850                 yaffs_trace(YAFFS_TRACE_GC,
2851                         "GC Selected block %d with %d free, prioritised:%d",
2852                         selected,
2853                         dev->param.chunks_per_block - dev->gc_pages_in_use,
2854                         prioritised);
2855
2856                 dev->n_gc_blocks++;
2857                 if (background)
2858                         dev->bg_gcs++;
2859
2860                 dev->gc_dirtiest = 0;
2861                 dev->gc_pages_in_use = 0;
2862                 dev->gc_not_done = 0;
2863                 if (dev->refresh_skip > 0)
2864                         dev->refresh_skip--;
2865         } else {
2866                 dev->gc_not_done++;
2867                 yaffs_trace(YAFFS_TRACE_GC,
2868                         "GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s",
2869                         dev->gc_block_finder, dev->gc_not_done, threshold,
2870                         dev->gc_dirtiest, dev->gc_pages_in_use,
2871                         dev->oldest_dirty_block, background ? " bg" : "");
2872         }
2873
2874         return selected;
2875 }
2876
2877 /* New garbage collector
2878  * If we're very low on erased blocks then we do aggressive garbage collection
2879  * otherwise we do "leasurely" garbage collection.
2880  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2881  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
2882  *
2883  * The idea is to help clear out space in a more spread-out manner.
2884  * Dunno if it really does anything useful.
2885  */
2886 static int yaffs_check_gc(struct yaffs_dev *dev, int background)
2887 {
2888         int aggressive = 0;
2889         int gc_ok = YAFFS_OK;
2890         int max_tries = 0;
2891         int min_erased;
2892         int erased_chunks;
2893         int checkpt_block_adjust;
2894
2895         if (dev->param.gc_control && (dev->param.gc_control(dev) & 1) == 0)
2896                 return YAFFS_OK;
2897
2898         if (dev->gc_disable) {
2899                 /* Bail out so we don't get recursive gc */
2900                 return YAFFS_OK;
2901         }
2902
2903         /* This loop should pass the first time.
2904          * We'll only see looping here if the collection does not increase space.
2905          */
2906
2907         do {
2908                 max_tries++;
2909
2910                 checkpt_block_adjust = yaffs_calc_checkpt_blocks_required(dev);
2911
2912                 min_erased =
2913                     dev->param.n_reserved_blocks + checkpt_block_adjust + 1;
2914                 erased_chunks =
2915                     dev->n_erased_blocks * dev->param.chunks_per_block;
2916
2917                 /* If we need a block soon then do aggressive gc. */
2918                 if (dev->n_erased_blocks < min_erased)
2919                         aggressive = 1;
2920                 else {
2921                         if (!background
2922                             && erased_chunks > (dev->n_free_chunks / 4))
2923                                 break;
2924
2925                         if (dev->gc_skip > 20)
2926                                 dev->gc_skip = 20;
2927                         if (erased_chunks < dev->n_free_chunks / 2 ||
2928                             dev->gc_skip < 1 || background)
2929                                 aggressive = 0;
2930                         else {
2931                                 dev->gc_skip--;
2932                                 break;
2933                         }
2934                 }
2935
2936                 dev->gc_skip = 5;
2937
2938                 /* If we don't already have a block being gc'd then see if we should start another */
2939
2940                 if (dev->gc_block < 1 && !aggressive) {
2941                         dev->gc_block = yaffs2_find_refresh_block(dev);
2942                         dev->gc_chunk = 0;
2943                         dev->n_clean_ups = 0;
2944                 }
2945                 if (dev->gc_block < 1) {
2946                         dev->gc_block =
2947                             yaffs_find_gc_block(dev, aggressive, background);
2948                         dev->gc_chunk = 0;
2949                         dev->n_clean_ups = 0;
2950                 }
2951
2952                 if (dev->gc_block > 0) {
2953                         dev->all_gcs++;
2954                         if (!aggressive)
2955                                 dev->passive_gc_count++;
2956
2957                         yaffs_trace(YAFFS_TRACE_GC,
2958                                 "yaffs: GC n_erased_blocks %d aggressive %d",
2959                                 dev->n_erased_blocks, aggressive);
2960
2961                         gc_ok = yaffs_gc_block(dev, dev->gc_block, aggressive);
2962                 }
2963
2964                 if (dev->n_erased_blocks < (dev->param.n_reserved_blocks)
2965                     && dev->gc_block > 0) {
2966                         yaffs_trace(YAFFS_TRACE_GC,
2967                                 "yaffs: GC !!!no reclaim!!! n_erased_blocks %d after try %d block %d",
2968                                 dev->n_erased_blocks, max_tries,
2969                                 dev->gc_block);
2970                 }
2971         } while ((dev->n_erased_blocks < dev->param.n_reserved_blocks) &&
2972                  (dev->gc_block > 0) && (max_tries < 2));
2973
2974         return aggressive ? gc_ok : YAFFS_OK;
2975 }
2976
2977 /*
2978  * yaffs_bg_gc()
2979  * Garbage collects. Intended to be called from a background thread.
2980  * Returns non-zero if at least half the free chunks are erased.
2981  */
2982 int yaffs_bg_gc(struct yaffs_dev *dev, unsigned urgency)
2983 {
2984         int erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
2985
2986         yaffs_trace(YAFFS_TRACE_BACKGROUND, "Background gc %u", urgency);
2987
2988         yaffs_check_gc(dev, 1);
2989         return erased_chunks > dev->n_free_chunks / 2;
2990 }
2991
2992 /*-------------------- Data file manipulation -----------------*/
2993
2994 static int yaffs_rd_data_obj(struct yaffs_obj *in, int inode_chunk, u8 * buffer)
2995 {
2996         int nand_chunk = yaffs_find_chunk_in_file(in, inode_chunk, NULL);
2997
2998         if (nand_chunk >= 0)
2999                 return yaffs_rd_chunk_tags_nand(in->my_dev, nand_chunk,
3000                                                 buffer, NULL);
3001         else {
3002                 yaffs_trace(YAFFS_TRACE_NANDACCESS,
3003                         "Chunk %d not found zero instead",
3004                         nand_chunk);
3005                 /* get sane (zero) data if you read a hole */
3006                 memset(buffer, 0, in->my_dev->data_bytes_per_chunk);
3007                 return 0;
3008         }
3009
3010 }
3011
3012 void yaffs_chunk_del(struct yaffs_dev *dev, int chunk_id, int mark_flash,
3013                      int lyn)
3014 {
3015         int block;
3016         int page;
3017         struct yaffs_ext_tags tags;
3018         struct yaffs_block_info *bi;
3019
3020         if (chunk_id <= 0)
3021                 return;
3022
3023         dev->n_deletions++;
3024         block = chunk_id / dev->param.chunks_per_block;
3025         page = chunk_id % dev->param.chunks_per_block;
3026
3027         if (!yaffs_check_chunk_bit(dev, block, page))
3028                 yaffs_trace(YAFFS_TRACE_VERIFY,
3029                         "Deleting invalid chunk %d", chunk_id);
3030
3031         bi = yaffs_get_block_info(dev, block);
3032
3033         yaffs2_update_oldest_dirty_seq(dev, block, bi);
3034
3035         yaffs_trace(YAFFS_TRACE_DELETION,
3036                 "line %d delete of chunk %d",
3037                 lyn, chunk_id);
3038
3039         if (!dev->param.is_yaffs2 && mark_flash &&
3040             bi->block_state != YAFFS_BLOCK_STATE_COLLECTING) {
3041
3042                 yaffs_init_tags(&tags);
3043
3044                 tags.is_deleted = 1;
3045
3046                 yaffs_wr_chunk_tags_nand(dev, chunk_id, NULL, &tags);
3047                 yaffs_handle_chunk_update(dev, chunk_id, &tags);
3048         } else {
3049                 dev->n_unmarked_deletions++;
3050         }
3051
3052         /* Pull out of the management area.
3053          * If the whole block became dirty, this will kick off an erasure.
3054          */
3055         if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING ||
3056             bi->block_state == YAFFS_BLOCK_STATE_FULL ||
3057             bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
3058             bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
3059                 dev->n_free_chunks++;
3060
3061                 yaffs_clear_chunk_bit(dev, block, page);
3062
3063                 bi->pages_in_use--;
3064
3065                 if (bi->pages_in_use == 0 &&
3066                     !bi->has_shrink_hdr &&
3067                     bi->block_state != YAFFS_BLOCK_STATE_ALLOCATING &&
3068                     bi->block_state != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
3069                         yaffs_block_became_dirty(dev, block);
3070                 }
3071
3072         }
3073
3074 }
3075
3076 static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
3077                              const u8 * buffer, int n_bytes, int use_reserve)
3078 {
3079         /* Find old chunk Need to do this to get serial number
3080          * Write new one and patch into tree.
3081          * Invalidate old tags.
3082          */
3083
3084         int prev_chunk_id;
3085         struct yaffs_ext_tags prev_tags;
3086
3087         int new_chunk_id;
3088         struct yaffs_ext_tags new_tags;
3089
3090         struct yaffs_dev *dev = in->my_dev;
3091
3092         yaffs_check_gc(dev, 0);
3093
3094         /* Get the previous chunk at this location in the file if it exists.
3095          * If it does not exist then put a zero into the tree. This creates
3096          * the tnode now, rather than later when it is harder to clean up.
3097          */
3098         prev_chunk_id = yaffs_find_chunk_in_file(in, inode_chunk, &prev_tags);
3099         if (prev_chunk_id < 1 &&
3100             !yaffs_put_chunk_in_file(in, inode_chunk, 0, 0))
3101                 return 0;
3102
3103         /* Set up new tags */
3104         yaffs_init_tags(&new_tags);
3105
3106         new_tags.chunk_id = inode_chunk;
3107         new_tags.obj_id = in->obj_id;
3108         new_tags.serial_number =
3109             (prev_chunk_id > 0) ? prev_tags.serial_number + 1 : 1;
3110         new_tags.n_bytes = n_bytes;
3111
3112         if (n_bytes < 1 || n_bytes > dev->param.total_bytes_per_chunk) {
3113                 yaffs_trace(YAFFS_TRACE_ERROR,
3114                   "Writing %d bytes to chunk!!!!!!!!!",
3115                    n_bytes);
3116                 YBUG();
3117         }
3118
3119         new_chunk_id =
3120             yaffs_write_new_chunk(dev, buffer, &new_tags, use_reserve);
3121
3122         if (new_chunk_id > 0) {
3123                 yaffs_put_chunk_in_file(in, inode_chunk, new_chunk_id, 0);
3124
3125                 if (prev_chunk_id > 0)
3126                         yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
3127
3128                 yaffs_verify_file_sane(in);
3129         }
3130         return new_chunk_id;
3131
3132 }
3133
3134
3135
3136 static int yaffs_do_xattrib_mod(struct yaffs_obj *obj, int set,
3137                                 const YCHAR * name, const void *value, int size,
3138                                 int flags)
3139 {
3140         struct yaffs_xattr_mod xmod;
3141
3142         int result;
3143
3144         xmod.set = set;
3145         xmod.name = name;
3146         xmod.data = value;
3147         xmod.size = size;
3148         xmod.flags = flags;
3149         xmod.result = -ENOSPC;
3150
3151         result = yaffs_update_oh(obj, NULL, 0, 0, 0, &xmod);
3152
3153         if (result > 0)
3154                 return xmod.result;
3155         else
3156                 return -ENOSPC;
3157 }
3158
3159 static int yaffs_apply_xattrib_mod(struct yaffs_obj *obj, char *buffer,
3160                                    struct yaffs_xattr_mod *xmod)
3161 {
3162         int retval = 0;
3163         int x_offs = sizeof(struct yaffs_obj_hdr);
3164         struct yaffs_dev *dev = obj->my_dev;
3165         int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
3166
3167         char *x_buffer = buffer + x_offs;
3168
3169         if (xmod->set)
3170                 retval =
3171                     nval_set(x_buffer, x_size, xmod->name, xmod->data,
3172                              xmod->size, xmod->flags);
3173         else
3174                 retval = nval_del(x_buffer, x_size, xmod->name);
3175
3176         obj->has_xattr = nval_hasvalues(x_buffer, x_size);
3177         obj->xattr_known = 1;
3178
3179         xmod->result = retval;
3180
3181         return retval;
3182 }
3183
3184 static int yaffs_do_xattrib_fetch(struct yaffs_obj *obj, const YCHAR * name,
3185                                   void *value, int size)
3186 {
3187         char *buffer = NULL;
3188         int result;
3189         struct yaffs_ext_tags tags;
3190         struct yaffs_dev *dev = obj->my_dev;
3191         int x_offs = sizeof(struct yaffs_obj_hdr);
3192         int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
3193
3194         char *x_buffer;
3195
3196         int retval = 0;
3197
3198         if (obj->hdr_chunk < 1)
3199                 return -ENODATA;
3200
3201         /* If we know that the object has no xattribs then don't do all the
3202          * reading and parsing.
3203          */
3204         if (obj->xattr_known && !obj->has_xattr) {
3205                 if (name)
3206                         return -ENODATA;
3207                 else
3208                         return 0;
3209         }
3210
3211         buffer = (char *)yaffs_get_temp_buffer(dev, __LINE__);
3212         if (!buffer)
3213                 return -ENOMEM;
3214
3215         result =
3216             yaffs_rd_chunk_tags_nand(dev, obj->hdr_chunk, (u8 *) buffer, &tags);
3217
3218         if (result != YAFFS_OK)
3219                 retval = -ENOENT;
3220         else {
3221                 x_buffer = buffer + x_offs;
3222
3223                 if (!obj->xattr_known) {
3224                         obj->has_xattr = nval_hasvalues(x_buffer, x_size);
3225                         obj->xattr_known = 1;
3226                 }
3227
3228                 if (name)
3229                         retval = nval_get(x_buffer, x_size, name, value, size);
3230                 else
3231                         retval = nval_list(x_buffer, x_size, value, size);
3232         }
3233         yaffs_release_temp_buffer(dev, (u8 *) buffer, __LINE__);
3234         return retval;
3235 }
3236
3237 int yaffs_set_xattrib(struct yaffs_obj *obj, const YCHAR * name,
3238                       const void *value, int size, int flags)
3239 {
3240         return yaffs_do_xattrib_mod(obj, 1, name, value, size, flags);
3241 }
3242
3243 int yaffs_remove_xattrib(struct yaffs_obj *obj, const YCHAR * name)
3244 {
3245         return yaffs_do_xattrib_mod(obj, 0, name, NULL, 0, 0);
3246 }
3247
3248 int yaffs_get_xattrib(struct yaffs_obj *obj, const YCHAR * name, void *value,
3249                       int size)
3250 {
3251         return yaffs_do_xattrib_fetch(obj, name, value, size);
3252 }
3253
3254 int yaffs_list_xattrib(struct yaffs_obj *obj, char *buffer, int size)
3255 {
3256         return yaffs_do_xattrib_fetch(obj, NULL, buffer, size);
3257 }
3258
3259 static void yaffs_check_obj_details_loaded(struct yaffs_obj *in)
3260 {
3261         u8 *chunk_data;
3262         struct yaffs_obj_hdr *oh;
3263         struct yaffs_dev *dev;
3264         struct yaffs_ext_tags tags;
3265         int result;
3266         int alloc_failed = 0;
3267
3268         if (!in)
3269                 return;
3270
3271         dev = in->my_dev;
3272
3273         if (in->lazy_loaded && in->hdr_chunk > 0) {
3274                 in->lazy_loaded = 0;
3275                 chunk_data = yaffs_get_temp_buffer(dev, __LINE__);
3276
3277                 result =
3278                     yaffs_rd_chunk_tags_nand(dev, in->hdr_chunk, chunk_data,
3279                                              &tags);
3280                 oh = (struct yaffs_obj_hdr *)chunk_data;
3281
3282                 in->yst_mode = oh->yst_mode;
3283                 yaffs_load_attribs(in, oh);
3284                 yaffs_set_obj_name_from_oh(in, oh);
3285
3286                 if (in->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
3287                         in->variant.symlink_variant.alias =
3288                             yaffs_clone_str(oh->alias);
3289                         if (!in->variant.symlink_variant.alias)
3290                                 alloc_failed = 1;       /* Not returned to caller */
3291                 }
3292
3293                 yaffs_release_temp_buffer(dev, chunk_data, __LINE__);
3294         }
3295 }
3296
3297 static void yaffs_load_name_from_oh(struct yaffs_dev *dev, YCHAR * name,
3298                                     const YCHAR * oh_name, int buff_size)
3299 {
3300 #ifdef CONFIG_YAFFS_AUTO_UNICODE
3301         if (dev->param.auto_unicode) {
3302                 if (*oh_name) {
3303                         /* It is an ASCII name, do an ASCII to
3304                          * unicode conversion */
3305                         const char *ascii_oh_name = (const char *)oh_name;
3306                         int n = buff_size - 1;
3307                         while (n > 0 && *ascii_oh_name) {
3308                                 *name = *ascii_oh_name;
3309                                 name++;
3310                                 ascii_oh_name++;
3311                                 n--;
3312                         }
3313                 } else {
3314                         strncpy(name, oh_name + 1, buff_size - 1);
3315                 }
3316         } else {
3317 #else
3318         {
3319 #endif
3320                 strncpy(name, oh_name, buff_size - 1);
3321         }
3322 }
3323
3324 static void yaffs_load_oh_from_name(struct yaffs_dev *dev, YCHAR * oh_name,
3325                                     const YCHAR * name)
3326 {
3327 #ifdef CONFIG_YAFFS_AUTO_UNICODE
3328
3329         int is_ascii;
3330         YCHAR *w;
3331
3332         if (dev->param.auto_unicode) {
3333
3334                 is_ascii = 1;
3335                 w = name;
3336
3337                 /* Figure out if the name will fit in ascii character set */
3338                 while (is_ascii && *w) {
3339                         if ((*w) & 0xff00)
3340                                 is_ascii = 0;
3341                         w++;
3342                 }
3343
3344                 if (is_ascii) {
3345                         /* It is an ASCII name, so do a unicode to ascii conversion */
3346                         char *ascii_oh_name = (char *)oh_name;
3347                         int n = YAFFS_MAX_NAME_LENGTH - 1;
3348                         while (n > 0 && *name) {
3349                                 *ascii_oh_name = *name;
3350                                 name++;
3351                                 ascii_oh_name++;
3352                                 n--;
3353                         }
3354                 } else {
3355                         /* It is a unicode name, so save starting at the second YCHAR */
3356                         *oh_name = 0;
3357                         strncpy(oh_name + 1, name,
3358                                       YAFFS_MAX_NAME_LENGTH - 2);
3359                 }
3360         } else {
3361 #else
3362         {
3363 #endif
3364                 strncpy(oh_name, name, YAFFS_MAX_NAME_LENGTH - 1);
3365         }
3366
3367 }
3368
3369 /* UpdateObjectHeader updates the header on NAND for an object.
3370  * If name is not NULL, then that new name is used.
3371  */
3372 int yaffs_update_oh(struct yaffs_obj *in, const YCHAR * name, int force,
3373                     int is_shrink, int shadows, struct yaffs_xattr_mod *xmod)
3374 {
3375
3376         struct yaffs_block_info *bi;
3377
3378         struct yaffs_dev *dev = in->my_dev;
3379
3380         int prev_chunk_id;
3381         int ret_val = 0;
3382         int result = 0;
3383
3384         int new_chunk_id;
3385         struct yaffs_ext_tags new_tags;
3386         struct yaffs_ext_tags old_tags;
3387         const YCHAR *alias = NULL;
3388
3389         u8 *buffer = NULL;
3390         YCHAR old_name[YAFFS_MAX_NAME_LENGTH + 1];
3391
3392         struct yaffs_obj_hdr *oh = NULL;
3393
3394         strcpy(old_name, _Y("silly old name"));
3395
3396         if (!in->fake || in == dev->root_dir ||
3397             force || xmod) {
3398
3399                 yaffs_check_gc(dev, 0);
3400                 yaffs_check_obj_details_loaded(in);
3401
3402                 buffer = yaffs_get_temp_buffer(in->my_dev, __LINE__);
3403                 oh = (struct yaffs_obj_hdr *)buffer;
3404
3405                 prev_chunk_id = in->hdr_chunk;
3406
3407                 if (prev_chunk_id > 0) {
3408                         result = yaffs_rd_chunk_tags_nand(dev, prev_chunk_id,
3409                                                           buffer, &old_tags);
3410
3411                         yaffs_verify_oh(in, oh, &old_tags, 0);
3412
3413                         memcpy(old_name, oh->name, sizeof(oh->name));
3414                         memset(buffer, 0xFF, sizeof(struct yaffs_obj_hdr));
3415                 } else {
3416                         memset(buffer, 0xFF, dev->data_bytes_per_chunk);
3417                 }
3418
3419                 oh->type = in->variant_type;
3420                 oh->yst_mode = in->yst_mode;
3421                 oh->shadows_obj = oh->inband_shadowed_obj_id = shadows;
3422
3423                 yaffs_load_attribs_oh(oh, in);
3424
3425                 if (in->parent)
3426                         oh->parent_obj_id = in->parent->obj_id;
3427                 else
3428                         oh->parent_obj_id = 0;
3429
3430                 if (name && *name) {
3431                         memset(oh->name, 0, sizeof(oh->name));
3432                         yaffs_load_oh_from_name(dev, oh->name, name);
3433                 } else if (prev_chunk_id > 0) {
3434                         memcpy(oh->name, old_name, sizeof(oh->name));
3435                 } else {
3436                         memset(oh->name, 0, sizeof(oh->name));
3437                 }
3438
3439                 oh->is_shrink = is_shrink;
3440
3441                 switch (in->variant_type) {
3442                 case YAFFS_OBJECT_TYPE_UNKNOWN:
3443                         /* Should not happen */
3444                         break;
3445                 case YAFFS_OBJECT_TYPE_FILE:
3446                         oh->file_size =
3447                             (oh->parent_obj_id == YAFFS_OBJECTID_DELETED
3448                              || oh->parent_obj_id ==
3449                              YAFFS_OBJECTID_UNLINKED) ? 0 : in->
3450                             variant.file_variant.file_size;
3451                         break;
3452                 case YAFFS_OBJECT_TYPE_HARDLINK:
3453                         oh->equiv_id = in->variant.hardlink_variant.equiv_id;
3454                         break;
3455                 case YAFFS_OBJECT_TYPE_SPECIAL:
3456                         /* Do nothing */
3457                         break;
3458                 case YAFFS_OBJECT_TYPE_DIRECTORY:
3459                         /* Do nothing */
3460                         break;
3461                 case YAFFS_OBJECT_TYPE_SYMLINK:
3462                         alias = in->variant.symlink_variant.alias;
3463                         if (!alias)
3464                                 alias = _Y("no alias");
3465                         strncpy(oh->alias, alias, YAFFS_MAX_ALIAS_LENGTH);
3466                         oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3467                         break;
3468                 }
3469
3470                 /* process any xattrib modifications */
3471                 if (xmod)
3472                         yaffs_apply_xattrib_mod(in, (char *)buffer, xmod);
3473
3474                 /* Tags */
3475                 yaffs_init_tags(&new_tags);
3476                 in->serial++;
3477                 new_tags.chunk_id = 0;
3478                 new_tags.obj_id = in->obj_id;
3479                 new_tags.serial_number = in->serial;
3480
3481                 /* Add extra info for file header */
3482
3483                 new_tags.extra_available = 1;
3484                 new_tags.extra_parent_id = oh->parent_obj_id;
3485                 new_tags.extra_length = oh->file_size;
3486                 new_tags.extra_is_shrink = oh->is_shrink;
3487                 new_tags.extra_equiv_id = oh->equiv_id;
3488                 new_tags.extra_shadows = (oh->shadows_obj > 0) ? 1 : 0;
3489                 new_tags.extra_obj_type = in->variant_type;
3490
3491                 yaffs_verify_oh(in, oh, &new_tags, 1);
3492
3493                 /* Create new chunk in NAND */
3494                 new_chunk_id =
3495                     yaffs_write_new_chunk(dev, buffer, &new_tags,
3496                                           (prev_chunk_id > 0) ? 1 : 0);
3497
3498                 if (new_chunk_id >= 0) {
3499
3500                         in->hdr_chunk = new_chunk_id;
3501
3502                         if (prev_chunk_id > 0) {
3503                                 yaffs_chunk_del(dev, prev_chunk_id, 1,
3504                                                 __LINE__);
3505                         }
3506
3507                         if (!yaffs_obj_cache_dirty(in))
3508                                 in->dirty = 0;
3509
3510                         /* If this was a shrink, then mark the block that the chunk lives on */
3511                         if (is_shrink) {
3512                                 bi = yaffs_get_block_info(in->my_dev,
3513                                                           new_chunk_id /
3514                                                           in->my_dev->param.
3515                                                           chunks_per_block);
3516                                 bi->has_shrink_hdr = 1;
3517                         }
3518
3519                 }
3520
3521                 ret_val = new_chunk_id;
3522
3523         }
3524
3525         if (buffer)
3526                 yaffs_release_temp_buffer(dev, buffer, __LINE__);
3527
3528         return ret_val;
3529 }
3530
3531 /*--------------------- File read/write ------------------------
3532  * Read and write have very similar structures.
3533  * In general the read/write has three parts to it
3534  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3535  * Some complete chunks
3536  * An incomplete chunk to end off with
3537  *
3538  * Curve-balls: the first chunk might also be the last chunk.
3539  */
3540
3541 int yaffs_file_rd(struct yaffs_obj *in, u8 * buffer, loff_t offset, int n_bytes)
3542 {
3543
3544         int chunk;
3545         u32 start;
3546         int n_copy;
3547         int n = n_bytes;
3548         int n_done = 0;
3549         struct yaffs_cache *cache;
3550
3551         struct yaffs_dev *dev;
3552
3553         dev = in->my_dev;
3554
3555         while (n > 0) {
3556                 /* chunk = offset / dev->data_bytes_per_chunk + 1; */
3557                 /* start = offset % dev->data_bytes_per_chunk; */
3558                 yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3559                 chunk++;
3560
3561                 /* OK now check for the curveball where the start and end are in
3562                  * the same chunk.
3563                  */
3564                 if ((start + n) < dev->data_bytes_per_chunk)
3565                         n_copy = n;
3566                 else
3567                         n_copy = dev->data_bytes_per_chunk - start;
3568
3569                 cache = yaffs_find_chunk_cache(in, chunk);
3570
3571                 /* If the chunk is already in the cache or it is less than a whole chunk
3572                  * or we're using inband tags then use the cache (if there is caching)
3573                  * else bypass the cache.
3574                  */
3575                 if (cache || n_copy != dev->data_bytes_per_chunk
3576                     || dev->param.inband_tags) {
3577                         if (dev->param.n_caches > 0) {
3578
3579                                 /* If we can't find the data in the cache, then load it up. */
3580
3581                                 if (!cache) {
3582                                         cache =
3583                                             yaffs_grab_chunk_cache(in->my_dev);
3584                                         cache->object = in;
3585                                         cache->chunk_id = chunk;
3586                                         cache->dirty = 0;
3587                                         cache->locked = 0;
3588                                         yaffs_rd_data_obj(in, chunk,
3589                                                           cache->data);
3590                                         cache->n_bytes = 0;
3591                                 }
3592
3593                                 yaffs_use_cache(dev, cache, 0);
3594
3595                                 cache->locked = 1;
3596
3597                                 memcpy(buffer, &cache->data[start], n_copy);
3598
3599                                 cache->locked = 0;
3600                         } else {
3601                                 /* Read into the local buffer then copy.. */
3602
3603                                 u8 *local_buffer =
3604                                     yaffs_get_temp_buffer(dev, __LINE__);
3605                                 yaffs_rd_data_obj(in, chunk, local_buffer);
3606
3607                                 memcpy(buffer, &local_buffer[start], n_copy);
3608
3609                                 yaffs_release_temp_buffer(dev, local_buffer,
3610                                                           __LINE__);
3611                         }
3612
3613                 } else {
3614
3615                         /* A full chunk. Read directly into the supplied buffer. */
3616                         yaffs_rd_data_obj(in, chunk, buffer);
3617
3618                 }
3619
3620                 n -= n_copy;
3621                 offset += n_copy;
3622                 buffer += n_copy;
3623                 n_done += n_copy;
3624
3625         }
3626
3627         return n_done;
3628 }
3629
3630 int yaffs_do_file_wr(struct yaffs_obj *in, const u8 * buffer, loff_t offset,
3631                      int n_bytes, int write_trhrough)
3632 {
3633
3634         int chunk;
3635         u32 start;
3636         int n_copy;
3637         int n = n_bytes;
3638         int n_done = 0;
3639         int n_writeback;
3640         int start_write = offset;
3641         int chunk_written = 0;
3642         u32 n_bytes_read;
3643         u32 chunk_start;
3644
3645         struct yaffs_dev *dev;
3646
3647         dev = in->my_dev;
3648
3649         while (n > 0 && chunk_written >= 0) {
3650                 yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3651
3652                 if (chunk * dev->data_bytes_per_chunk + start != offset ||
3653                     start >= dev->data_bytes_per_chunk) {
3654                         yaffs_trace(YAFFS_TRACE_ERROR,
3655                                 "AddrToChunk of offset %d gives chunk %d start %d",
3656                                 (int)offset, chunk, start);
3657                 }
3658                 chunk++;        /* File pos to chunk in file offset */
3659
3660                 /* OK now check for the curveball where the start and end are in
3661                  * the same chunk.
3662                  */
3663
3664                 if ((start + n) < dev->data_bytes_per_chunk) {
3665                         n_copy = n;
3666
3667                         /* Now folks, to calculate how many bytes to write back....
3668                          * If we're overwriting and not writing to then end of file then
3669                          * we need to write back as much as was there before.
3670                          */
3671
3672                         chunk_start = ((chunk - 1) * dev->data_bytes_per_chunk);
3673
3674                         if (chunk_start > in->variant.file_variant.file_size)
3675                                 n_bytes_read = 0;       /* Past end of file */
3676                         else
3677                                 n_bytes_read =
3678                                     in->variant.file_variant.file_size -
3679                                     chunk_start;
3680
3681                         if (n_bytes_read > dev->data_bytes_per_chunk)
3682                                 n_bytes_read = dev->data_bytes_per_chunk;
3683
3684                         n_writeback =
3685                             (n_bytes_read >
3686                              (start + n)) ? n_bytes_read : (start + n);
3687
3688                         if (n_writeback < 0
3689                             || n_writeback > dev->data_bytes_per_chunk)
3690                                 YBUG();
3691
3692                 } else {
3693                         n_copy = dev->data_bytes_per_chunk - start;
3694                         n_writeback = dev->data_bytes_per_chunk;
3695                 }
3696
3697                 if (n_copy != dev->data_bytes_per_chunk
3698                     || dev->param.inband_tags) {
3699                         /* An incomplete start or end chunk (or maybe both start and end chunk),
3700                          * or we're using inband tags, so we want to use the cache buffers.
3701                          */
3702                         if (dev->param.n_caches > 0) {
3703                                 struct yaffs_cache *cache;
3704                                 /* If we can't find the data in the cache, then load the cache */
3705                                 cache = yaffs_find_chunk_cache(in, chunk);
3706
3707                                 if (!cache
3708                                     && yaffs_check_alloc_available(dev, 1)) {
3709                                         cache = yaffs_grab_chunk_cache(dev);
3710                                         cache->object = in;
3711                                         cache->chunk_id = chunk;
3712                                         cache->dirty = 0;
3713                                         cache->locked = 0;
3714                                         yaffs_rd_data_obj(in, chunk,
3715                                                           cache->data);
3716                                 } else if (cache &&
3717                                            !cache->dirty &&
3718                                            !yaffs_check_alloc_available(dev,
3719                                                                         1)) {
3720                                         /* Drop the cache if it was a read cache item and
3721                                          * no space check has been made for it.
3722                                          */
3723                                         cache = NULL;
3724                                 }
3725
3726                                 if (cache) {
3727                                         yaffs_use_cache(dev, cache, 1);
3728                                         cache->locked = 1;
3729
3730                                         memcpy(&cache->data[start], buffer,
3731                                                n_copy);
3732
3733                                         cache->locked = 0;
3734                                         cache->n_bytes = n_writeback;
3735
3736                                         if (write_trhrough) {
3737                                                 chunk_written =
3738                                                     yaffs_wr_data_obj
3739                                                     (cache->object,
3740                                                      cache->chunk_id,
3741                                                      cache->data,
3742                                                      cache->n_bytes, 1);
3743                                                 cache->dirty = 0;
3744                                         }
3745
3746                                 } else {
3747                                         chunk_written = -1;     /* fail the write */
3748                                 }
3749                         } else {
3750                                 /* An incomplete start or end chunk (or maybe both start and end chunk)
3751                                  * Read into the local buffer then copy, then copy over and write back.
3752                                  */
3753
3754                                 u8 *local_buffer =
3755                                     yaffs_get_temp_buffer(dev, __LINE__);
3756
3757                                 yaffs_rd_data_obj(in, chunk, local_buffer);
3758
3759                                 memcpy(&local_buffer[start], buffer, n_copy);
3760
3761                                 chunk_written =
3762                                     yaffs_wr_data_obj(in, chunk,
3763                                                       local_buffer,
3764                                                       n_writeback, 0);
3765
3766                                 yaffs_release_temp_buffer(dev, local_buffer,
3767                                                           __LINE__);
3768
3769                         }
3770
3771                 } else {
3772                         /* A full chunk. Write directly from the supplied buffer. */
3773
3774                         chunk_written =
3775                             yaffs_wr_data_obj(in, chunk, buffer,
3776                                               dev->data_bytes_per_chunk, 0);
3777
3778                         /* Since we've overwritten the cached data, we better invalidate it. */
3779                         yaffs_invalidate_chunk_cache(in, chunk);
3780                 }
3781
3782                 if (chunk_written >= 0) {
3783                         n -= n_copy;
3784                         offset += n_copy;
3785                         buffer += n_copy;
3786                         n_done += n_copy;
3787                 }
3788
3789         }
3790
3791         /* Update file object */
3792
3793         if ((start_write + n_done) > in->variant.file_variant.file_size)
3794                 in->variant.file_variant.file_size = (start_write + n_done);
3795
3796         in->dirty = 1;
3797
3798         return n_done;
3799 }
3800
3801 int yaffs_wr_file(struct yaffs_obj *in, const u8 * buffer, loff_t offset,
3802                   int n_bytes, int write_trhrough)
3803 {
3804         yaffs2_handle_hole(in, offset);
3805         return yaffs_do_file_wr(in, buffer, offset, n_bytes, write_trhrough);
3806 }
3807
3808 /* ---------------------- File resizing stuff ------------------ */
3809
3810 static void yaffs_prune_chunks(struct yaffs_obj *in, int new_size)
3811 {
3812
3813         struct yaffs_dev *dev = in->my_dev;
3814         int old_size = in->variant.file_variant.file_size;
3815
3816         int last_del = 1 + (old_size - 1) / dev->data_bytes_per_chunk;
3817
3818         int start_del = 1 + (new_size + dev->data_bytes_per_chunk - 1) /
3819             dev->data_bytes_per_chunk;
3820         int i;
3821         int chunk_id;
3822
3823         /* Delete backwards so that we don't end up with holes if
3824          * power is lost part-way through the operation.
3825          */
3826         for (i = last_del; i >= start_del; i--) {
3827                 /* NB this could be optimised somewhat,
3828                  * eg. could retrieve the tags and write them without
3829                  * using yaffs_chunk_del
3830                  */
3831
3832                 chunk_id = yaffs_find_del_file_chunk(in, i, NULL);
3833                 if (chunk_id > 0) {
3834                         if (chunk_id <
3835                             (dev->internal_start_block *
3836                              dev->param.chunks_per_block)
3837                             || chunk_id >=
3838                             ((dev->internal_end_block +
3839                               1) * dev->param.chunks_per_block)) {
3840                                 yaffs_trace(YAFFS_TRACE_ALWAYS,
3841                                         "Found daft chunk_id %d for %d",
3842                                         chunk_id, i);
3843                         } else {
3844                                 in->n_data_chunks--;
3845                                 yaffs_chunk_del(dev, chunk_id, 1, __LINE__);
3846                         }
3847                 }
3848         }
3849
3850 }
3851
3852 void yaffs_resize_file_down(struct yaffs_obj *obj, loff_t new_size)
3853 {
3854         int new_full;
3855         u32 new_partial;
3856         struct yaffs_dev *dev = obj->my_dev;
3857
3858         yaffs_addr_to_chunk(dev, new_size, &new_full, &new_partial);
3859
3860         yaffs_prune_chunks(obj, new_size);
3861
3862         if (new_partial != 0) {
3863                 int last_chunk = 1 + new_full;
3864                 u8 *local_buffer = yaffs_get_temp_buffer(dev, __LINE__);
3865
3866                 /* Rewrite the last chunk with its new size and zero pad */
3867                 yaffs_rd_data_obj(obj, last_chunk, local_buffer);
3868                 memset(local_buffer + new_partial, 0,
3869                        dev->data_bytes_per_chunk - new_partial);
3870
3871                 yaffs_wr_data_obj(obj, last_chunk, local_buffer,
3872                                   new_partial, 1);
3873
3874                 yaffs_release_temp_buffer(dev, local_buffer, __LINE__);
3875         }
3876
3877         obj->variant.file_variant.file_size = new_size;
3878
3879         yaffs_prune_tree(dev, &obj->variant.file_variant);
3880 }
3881
3882 int yaffs_resize_file(struct yaffs_obj *in, loff_t new_size)
3883 {
3884         struct yaffs_dev *dev = in->my_dev;
3885         int old_size = in->variant.file_variant.file_size;
3886
3887         yaffs_flush_file_cache(in);
3888         yaffs_invalidate_whole_cache(in);
3889
3890         yaffs_check_gc(dev, 0);
3891
3892         if (in->variant_type != YAFFS_OBJECT_TYPE_FILE)
3893                 return YAFFS_FAIL;
3894
3895         if (new_size == old_size)
3896                 return YAFFS_OK;
3897
3898         if (new_size > old_size) {
3899                 yaffs2_handle_hole(in, new_size);
3900                 in->variant.file_variant.file_size = new_size;
3901         } else {
3902                 /* new_size < old_size */
3903                 yaffs_resize_file_down(in, new_size);
3904         }
3905
3906         /* Write a new object header to reflect the resize.
3907          * show we've shrunk the file, if need be
3908          * Do this only if the file is not in the deleted directories
3909          * and is not shadowed.
3910          */
3911         if (in->parent &&
3912             !in->is_shadowed &&
3913             in->parent->obj_id != YAFFS_OBJECTID_UNLINKED &&
3914             in->parent->obj_id != YAFFS_OBJECTID_DELETED)
3915                 yaffs_update_oh(in, NULL, 0, 0, 0, NULL);
3916
3917         return YAFFS_OK;
3918 }
3919
3920 int yaffs_flush_file(struct yaffs_obj *in, int update_time, int data_sync)
3921 {
3922         int ret_val;
3923         if (in->dirty) {
3924                 yaffs_flush_file_cache(in);
3925                 if (data_sync)  /* Only sync data */
3926                         ret_val = YAFFS_OK;
3927                 else {
3928                         if (update_time)
3929                                 yaffs_load_current_time(in, 0, 0);
3930
3931                         ret_val = (yaffs_update_oh(in, NULL, 0, 0, 0, NULL) >=
3932                                    0) ? YAFFS_OK : YAFFS_FAIL;
3933                 }
3934         } else {
3935                 ret_val = YAFFS_OK;
3936         }
3937
3938         return ret_val;
3939
3940 }
3941
3942
3943 /* yaffs_del_file deletes the whole file data
3944  * and the inode associated with the file.
3945  * It does not delete the links associated with the file.
3946  */
3947 static int yaffs_unlink_file_if_needed(struct yaffs_obj *in)
3948 {
3949
3950         int ret_val;
3951         int del_now = 0;
3952         struct yaffs_dev *dev = in->my_dev;
3953
3954         if (!in->my_inode)
3955                 del_now = 1;
3956
3957         if (del_now) {
3958                 ret_val =
3959                     yaffs_change_obj_name(in, in->my_dev->del_dir,
3960                                           _Y("deleted"), 0, 0);
3961                 yaffs_trace(YAFFS_TRACE_TRACING,
3962                         "yaffs: immediate deletion of file %d",
3963                         in->obj_id);
3964                 in->deleted = 1;
3965                 in->my_dev->n_deleted_files++;
3966                 if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3967                         yaffs_resize_file(in, 0);
3968                 yaffs_soft_del_file(in);
3969         } else {
3970                 ret_val =
3971                     yaffs_change_obj_name(in, in->my_dev->unlinked_dir,
3972                                           _Y("unlinked"), 0, 0);
3973         }
3974
3975         return ret_val;
3976 }
3977
3978 int yaffs_del_file(struct yaffs_obj *in)
3979 {
3980         int ret_val = YAFFS_OK;
3981         int deleted;            /* Need to cache value on stack if in is freed */
3982         struct yaffs_dev *dev = in->my_dev;
3983
3984         if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3985                 yaffs_resize_file(in, 0);
3986
3987         if (in->n_data_chunks > 0) {
3988                 /* Use soft deletion if there is data in the file.
3989                  * That won't be the case if it has been resized to zero.
3990                  */
3991                 if (!in->unlinked)
3992                         ret_val = yaffs_unlink_file_if_needed(in);
3993
3994                 deleted = in->deleted;
3995
3996                 if (ret_val == YAFFS_OK && in->unlinked && !in->deleted) {
3997                         in->deleted = 1;
3998                         deleted = 1;
3999                         in->my_dev->n_deleted_files++;
4000                         yaffs_soft_del_file(in);
4001                 }
4002                 return deleted ? YAFFS_OK : YAFFS_FAIL;
4003         } else {
4004                 /* The file has no data chunks so we toss it immediately */
4005                 yaffs_free_tnode(in->my_dev, in->variant.file_variant.top);
4006                 in->variant.file_variant.top = NULL;
4007                 yaffs_generic_obj_del(in);
4008
4009                 return YAFFS_OK;
4010         }
4011 }
4012
4013 int yaffs_is_non_empty_dir(struct yaffs_obj *obj)
4014 {
4015         return (obj &&
4016                 obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) &&
4017                 !(list_empty(&obj->variant.dir_variant.children));
4018 }
4019
4020 static int yaffs_del_dir(struct yaffs_obj *obj)
4021 {
4022         /* First check that the directory is empty. */
4023         if (yaffs_is_non_empty_dir(obj))
4024                 return YAFFS_FAIL;
4025
4026         return yaffs_generic_obj_del(obj);
4027 }
4028
4029 static int yaffs_del_symlink(struct yaffs_obj *in)
4030 {
4031         if (in->variant.symlink_variant.alias)
4032                 kfree(in->variant.symlink_variant.alias);
4033         in->variant.symlink_variant.alias = NULL;
4034
4035         return yaffs_generic_obj_del(in);
4036 }
4037
4038 static int yaffs_del_link(struct yaffs_obj *in)
4039 {
4040         /* remove this hardlink from the list assocaited with the equivalent
4041          * object
4042          */
4043         list_del_init(&in->hard_links);
4044         return yaffs_generic_obj_del(in);
4045 }
4046
4047 int yaffs_del_obj(struct yaffs_obj *obj)
4048 {
4049         int ret_val = -1;
4050         switch (obj->variant_type) {
4051         case YAFFS_OBJECT_TYPE_FILE:
4052                 ret_val = yaffs_del_file(obj);
4053                 break;
4054         case YAFFS_OBJECT_TYPE_DIRECTORY:
4055                 if (!list_empty(&obj->variant.dir_variant.dirty)) {
4056                         yaffs_trace(YAFFS_TRACE_BACKGROUND,
4057                                 "Remove object %d from dirty directories",
4058                                 obj->obj_id);
4059                         list_del_init(&obj->variant.dir_variant.dirty);
4060                 }
4061                 return yaffs_del_dir(obj);
4062                 break;
4063         case YAFFS_OBJECT_TYPE_SYMLINK:
4064                 ret_val = yaffs_del_symlink(obj);
4065                 break;
4066         case YAFFS_OBJECT_TYPE_HARDLINK:
4067                 ret_val = yaffs_del_link(obj);
4068                 break;
4069         case YAFFS_OBJECT_TYPE_SPECIAL:
4070                 ret_val = yaffs_generic_obj_del(obj);
4071                 break;
4072         case YAFFS_OBJECT_TYPE_UNKNOWN:
4073                 ret_val = 0;
4074                 break;          /* should not happen. */
4075         }
4076
4077         return ret_val;
4078 }
4079
4080 static int yaffs_unlink_worker(struct yaffs_obj *obj)
4081 {
4082
4083         int del_now = 0;
4084
4085         if (!obj->my_inode)
4086                 del_now = 1;
4087
4088         if (obj)
4089                 yaffs_update_parent(obj->parent);
4090
4091         if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
4092                 return yaffs_del_link(obj);
4093         } else if (!list_empty(&obj->hard_links)) {
4094                 /* Curve ball: We're unlinking an object that has a hardlink.
4095                  *
4096                  * This problem arises because we are not strictly following
4097                  * The Linux link/inode model.
4098                  *
4099                  * We can't really delete the object.
4100                  * Instead, we do the following:
4101                  * - Select a hardlink.
4102                  * - Unhook it from the hard links
4103                  * - Move it from its parent directory (so that the rename can work)
4104                  * - Rename the object to the hardlink's name.
4105                  * - Delete the hardlink
4106                  */
4107
4108                 struct yaffs_obj *hl;
4109                 struct yaffs_obj *parent;
4110                 int ret_val;
4111                 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
4112
4113                 hl = list_entry(obj->hard_links.next, struct yaffs_obj,
4114                                 hard_links);
4115
4116                 yaffs_get_obj_name(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
4117                 parent = hl->parent;
4118
4119                 list_del_init(&hl->hard_links);
4120
4121                 yaffs_add_obj_to_dir(obj->my_dev->unlinked_dir, hl);
4122
4123                 ret_val = yaffs_change_obj_name(obj, parent, name, 0, 0);
4124
4125                 if (ret_val == YAFFS_OK)
4126                         ret_val = yaffs_generic_obj_del(hl);
4127
4128                 return ret_val;
4129
4130         } else if (del_now) {
4131                 switch (obj->variant_type) {
4132                 case YAFFS_OBJECT_TYPE_FILE:
4133                         return yaffs_del_file(obj);
4134                         break;
4135                 case YAFFS_OBJECT_TYPE_DIRECTORY:
4136                         list_del_init(&obj->variant.dir_variant.dirty);
4137                         return yaffs_del_dir(obj);
4138                         break;
4139                 case YAFFS_OBJECT_TYPE_SYMLINK:
4140                         return yaffs_del_symlink(obj);
4141                         break;
4142                 case YAFFS_OBJECT_TYPE_SPECIAL:
4143                         return yaffs_generic_obj_del(obj);
4144                         break;
4145                 case YAFFS_OBJECT_TYPE_HARDLINK:
4146                 case YAFFS_OBJECT_TYPE_UNKNOWN:
4147                 default:
4148                         return YAFFS_FAIL;
4149                 }
4150         } else if (yaffs_is_non_empty_dir(obj)) {
4151                 return YAFFS_FAIL;
4152         } else {
4153                 return yaffs_change_obj_name(obj, obj->my_dev->unlinked_dir,
4154                                              _Y("unlinked"), 0, 0);
4155         }
4156 }
4157
4158 static int yaffs_unlink_obj(struct yaffs_obj *obj)
4159 {
4160
4161         if (obj && obj->unlink_allowed)
4162                 return yaffs_unlink_worker(obj);
4163
4164         return YAFFS_FAIL;
4165
4166 }
4167
4168 int yaffs_unlinker(struct yaffs_obj *dir, const YCHAR * name)
4169 {
4170         struct yaffs_obj *obj;
4171
4172         obj = yaffs_find_by_name(dir, name);
4173         return yaffs_unlink_obj(obj);
4174 }
4175
4176 /* Note:
4177  * If old_name is NULL then we take old_dir as the object to be renamed.
4178  */
4179 int yaffs_rename_obj(struct yaffs_obj *old_dir, const YCHAR * old_name,
4180                      struct yaffs_obj *new_dir, const YCHAR * new_name)
4181 {
4182         struct yaffs_obj *obj = NULL;
4183         struct yaffs_obj *existing_target = NULL;
4184         int force = 0;
4185         int result;
4186         struct yaffs_dev *dev;
4187
4188         if (!old_dir || old_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
4189                 YBUG();
4190         if (!new_dir || new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
4191                 YBUG();
4192
4193         dev = old_dir->my_dev;
4194
4195 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
4196         /* Special case for case insemsitive systems.
4197          * While look-up is case insensitive, the name isn't.
4198          * Therefore we might want to change x.txt to X.txt
4199          */
4200         if (old_dir == new_dir &&
4201                 old_name && new_name &&
4202                 strcmp(old_name, new_name) == 0)
4203                 force = 1;
4204 #endif
4205
4206         if (strnlen(new_name, YAFFS_MAX_NAME_LENGTH + 1) >
4207             YAFFS_MAX_NAME_LENGTH)
4208                 /* ENAMETOOLONG */
4209                 return YAFFS_FAIL;
4210
4211         if(old_name)
4212                 obj = yaffs_find_by_name(old_dir, old_name);
4213         else{
4214                 obj = old_dir;
4215                 old_dir = obj->parent;
4216         }
4217
4218
4219         if (obj && obj->rename_allowed) {
4220
4221                 /* Now do the handling for an existing target, if there is one */
4222
4223                 existing_target = yaffs_find_by_name(new_dir, new_name);
4224                 if (yaffs_is_non_empty_dir(existing_target)){
4225                         return YAFFS_FAIL;      /* ENOTEMPTY */
4226                 } else if (existing_target && existing_target != obj) {
4227                         /* Nuke the target first, using shadowing,
4228                          * but only if it isn't the same object.
4229                          *
4230                          * Note we must disable gc otherwise it can mess up the shadowing.
4231                          *
4232                          */
4233                         dev->gc_disable = 1;
4234                         yaffs_change_obj_name(obj, new_dir, new_name, force,
4235                                               existing_target->obj_id);
4236                         existing_target->is_shadowed = 1;
4237                         yaffs_unlink_obj(existing_target);
4238                         dev->gc_disable = 0;
4239                 }
4240
4241                 result = yaffs_change_obj_name(obj, new_dir, new_name, 1, 0);
4242
4243                 yaffs_update_parent(old_dir);
4244                 if (new_dir != old_dir)
4245                         yaffs_update_parent(new_dir);
4246
4247                 return result;
4248         }
4249         return YAFFS_FAIL;
4250 }
4251
4252 /*----------------------- Initialisation Scanning ---------------------- */
4253
4254 void yaffs_handle_shadowed_obj(struct yaffs_dev *dev, int obj_id,
4255                                int backward_scanning)
4256 {
4257         struct yaffs_obj *obj;
4258
4259         if (!backward_scanning) {
4260                 /* Handle YAFFS1 forward scanning case
4261                  * For YAFFS1 we always do the deletion
4262                  */
4263
4264         } else {
4265                 /* Handle YAFFS2 case (backward scanning)
4266                  * If the shadowed object exists then ignore.
4267                  */
4268                 obj = yaffs_find_by_number(dev, obj_id);
4269                 if (obj)
4270                         return;
4271         }
4272
4273         /* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
4274          * We put it in unlinked dir to be cleaned up after the scanning
4275          */
4276         obj =
4277             yaffs_find_or_create_by_number(dev, obj_id, YAFFS_OBJECT_TYPE_FILE);
4278         if (!obj)
4279                 return;
4280         obj->is_shadowed = 1;
4281         yaffs_add_obj_to_dir(dev->unlinked_dir, obj);
4282         obj->variant.file_variant.shrink_size = 0;
4283         obj->valid = 1;         /* So that we don't read any other info for this file */
4284
4285 }
4286
4287 void yaffs_link_fixup(struct yaffs_dev *dev, struct yaffs_obj *hard_list)
4288 {
4289         struct yaffs_obj *hl;
4290         struct yaffs_obj *in;
4291
4292         while (hard_list) {
4293                 hl = hard_list;
4294                 hard_list = (struct yaffs_obj *)(hard_list->hard_links.next);
4295
4296                 in = yaffs_find_by_number(dev,
4297                                           hl->variant.
4298                                           hardlink_variant.equiv_id);
4299
4300                 if (in) {
4301                         /* Add the hardlink pointers */
4302                         hl->variant.hardlink_variant.equiv_obj = in;
4303                         list_add(&hl->hard_links, &in->hard_links);
4304                 } else {
4305                         /* Todo Need to report/handle this better.
4306                          * Got a problem... hardlink to a non-existant object
4307                          */
4308                         hl->variant.hardlink_variant.equiv_obj = NULL;
4309                         INIT_LIST_HEAD(&hl->hard_links);
4310
4311                 }
4312         }
4313 }
4314
4315 static void yaffs_strip_deleted_objs(struct yaffs_dev *dev)
4316 {
4317         /*
4318          *  Sort out state of unlinked and deleted objects after scanning.
4319          */
4320         struct list_head *i;
4321         struct list_head *n;
4322         struct yaffs_obj *l;
4323
4324         if (dev->read_only)
4325                 return;
4326
4327         /* Soft delete all the unlinked files */
4328         list_for_each_safe(i, n,
4329                            &dev->unlinked_dir->variant.dir_variant.children) {
4330                 if (i) {
4331                         l = list_entry(i, struct yaffs_obj, siblings);
4332                         yaffs_del_obj(l);
4333                 }
4334         }
4335
4336         list_for_each_safe(i, n, &dev->del_dir->variant.dir_variant.children) {
4337                 if (i) {
4338                         l = list_entry(i, struct yaffs_obj, siblings);
4339                         yaffs_del_obj(l);
4340                 }
4341         }
4342
4343 }
4344
4345 /*
4346  * This code iterates through all the objects making sure that they are rooted.
4347  * Any unrooted objects are re-rooted in lost+found.
4348  * An object needs to be in one of:
4349  * - Directly under deleted, unlinked
4350  * - Directly or indirectly under root.
4351  *
4352  * Note:
4353  *  This code assumes that we don't ever change the current relationships between
4354  *  directories:
4355  *   root_dir->parent == unlinked_dir->parent == del_dir->parent == NULL
4356  *   lost-n-found->parent == root_dir
4357  *
4358  * This fixes the problem where directories might have inadvertently been deleted
4359  * leaving the object "hanging" without being rooted in the directory tree.
4360  */
4361
4362 static int yaffs_has_null_parent(struct yaffs_dev *dev, struct yaffs_obj *obj)
4363 {
4364         return (obj == dev->del_dir ||
4365                 obj == dev->unlinked_dir || obj == dev->root_dir);
4366 }
4367
4368 static void yaffs_fix_hanging_objs(struct yaffs_dev *dev)
4369 {
4370         struct yaffs_obj *obj;
4371         struct yaffs_obj *parent;
4372         int i;
4373         struct list_head *lh;
4374         struct list_head *n;
4375         int depth_limit;
4376         int hanging;
4377
4378         if (dev->read_only)
4379                 return;
4380
4381         /* Iterate through the objects in each hash entry,
4382          * looking at each object.
4383          * Make sure it is rooted.
4384          */
4385
4386         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
4387                 list_for_each_safe(lh, n, &dev->obj_bucket[i].list) {
4388                         if (lh) {
4389                                 obj =
4390                                     list_entry(lh, struct yaffs_obj, hash_link);
4391                                 parent = obj->parent;
4392
4393                                 if (yaffs_has_null_parent(dev, obj)) {
4394                                         /* These directories are not hanging */
4395                                         hanging = 0;
4396                                 } else if (!parent
4397                                            || parent->variant_type !=
4398                                            YAFFS_OBJECT_TYPE_DIRECTORY) {
4399                                         hanging = 1;
4400                                 } else if (yaffs_has_null_parent(dev, parent)) {
4401                                         hanging = 0;
4402                                 } else {
4403                                         /*
4404                                          * Need to follow the parent chain to see if it is hanging.
4405                                          */
4406                                         hanging = 0;
4407                                         depth_limit = 100;
4408
4409                                         while (parent != dev->root_dir &&
4410                                                parent->parent &&
4411                                                parent->parent->variant_type ==
4412                                                YAFFS_OBJECT_TYPE_DIRECTORY
4413                                                && depth_limit > 0) {
4414                                                 parent = parent->parent;
4415                                                 depth_limit--;
4416                                         }
4417                                         if (parent != dev->root_dir)
4418                                                 hanging = 1;
4419                                 }
4420                                 if (hanging) {
4421                                         yaffs_trace(YAFFS_TRACE_SCAN,
4422                                                 "Hanging object %d moved to lost and found",
4423                                                 obj->obj_id);
4424                                         yaffs_add_obj_to_dir(dev->lost_n_found,
4425                                                              obj);
4426                                 }
4427                         }
4428                 }
4429         }
4430 }
4431
4432 /*
4433  * Delete directory contents for cleaning up lost and found.
4434  */
4435 static void yaffs_del_dir_contents(struct yaffs_obj *dir)
4436 {
4437         struct yaffs_obj *obj;
4438         struct list_head *lh;
4439         struct list_head *n;
4440
4441         if (dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
4442                 YBUG();
4443
4444         list_for_each_safe(lh, n, &dir->variant.dir_variant.children) {
4445                 if (lh) {
4446                         obj = list_entry(lh, struct yaffs_obj, siblings);
4447                         if (obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY)
4448                                 yaffs_del_dir_contents(obj);
4449
4450                         yaffs_trace(YAFFS_TRACE_SCAN,
4451                                 "Deleting lost_found object %d",
4452                                 obj->obj_id);
4453
4454                         /* Need to use UnlinkObject since Delete would not handle
4455                          * hardlinked objects correctly.
4456                          */
4457                         yaffs_unlink_obj(obj);
4458                 }
4459         }
4460
4461 }
4462
4463 static void yaffs_empty_l_n_f(struct yaffs_dev *dev)
4464 {
4465         yaffs_del_dir_contents(dev->lost_n_found);
4466 }
4467
4468
4469 struct yaffs_obj *yaffs_find_by_name(struct yaffs_obj *directory,
4470                                      const YCHAR * name)
4471 {
4472         int sum;
4473
4474         struct list_head *i;
4475         YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
4476
4477         struct yaffs_obj *l;
4478
4479         if (!name)
4480                 return NULL;
4481
4482         if (!directory) {
4483                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4484                         "tragedy: yaffs_find_by_name: null pointer directory"
4485                         );
4486                 YBUG();
4487                 return NULL;
4488         }
4489         if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4490                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4491                         "tragedy: yaffs_find_by_name: non-directory"
4492                         );
4493                 YBUG();
4494         }
4495
4496         sum = yaffs_calc_name_sum(name);
4497
4498         list_for_each(i, &directory->variant.dir_variant.children) {
4499                 if (i) {
4500                         l = list_entry(i, struct yaffs_obj, siblings);
4501
4502                         if (l->parent != directory)
4503                                 YBUG();
4504
4505                         yaffs_check_obj_details_loaded(l);
4506
4507                         /* Special case for lost-n-found */
4508                         if (l->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4509                                 if (!strcmp(name, YAFFS_LOSTNFOUND_NAME))
4510                                         return l;
4511                         } else if (l->sum == sum
4512                                    || l->hdr_chunk <= 0) {
4513                                 /* LostnFound chunk called Objxxx
4514                                  * Do a real check
4515                                  */
4516                                 yaffs_get_obj_name(l, buffer,
4517                                                    YAFFS_MAX_NAME_LENGTH + 1);
4518                                 if (strncmp
4519                                     (name, buffer, YAFFS_MAX_NAME_LENGTH) == 0)
4520                                         return l;
4521                         }
4522                 }
4523         }
4524
4525         return NULL;
4526 }
4527
4528 /* GetEquivalentObject dereferences any hard links to get to the
4529  * actual object.
4530  */
4531
4532 struct yaffs_obj *yaffs_get_equivalent_obj(struct yaffs_obj *obj)
4533 {
4534         if (obj && obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
4535                 /* We want the object id of the equivalent object, not this one */
4536                 obj = obj->variant.hardlink_variant.equiv_obj;
4537                 yaffs_check_obj_details_loaded(obj);
4538         }
4539         return obj;
4540 }
4541
4542 /*
4543  *  A note or two on object names.
4544  *  * If the object name is missing, we then make one up in the form objnnn
4545  *
4546  *  * ASCII names are stored in the object header's name field from byte zero
4547  *  * Unicode names are historically stored starting from byte zero.
4548  *
4549  * Then there are automatic Unicode names...
4550  * The purpose of these is to save names in a way that can be read as
4551  * ASCII or Unicode names as appropriate, thus allowing a Unicode and ASCII
4552  * system to share files.
4553  *
4554  * These automatic unicode are stored slightly differently...
4555  *  - If the name can fit in the ASCII character space then they are saved as
4556  *    ascii names as per above.
4557  *  - If the name needs Unicode then the name is saved in Unicode
4558  *    starting at oh->name[1].
4559
4560  */
4561 static void yaffs_fix_null_name(struct yaffs_obj *obj, YCHAR * name,
4562                                 int buffer_size)
4563 {
4564         /* Create an object name if we could not find one. */
4565         if (strnlen(name, YAFFS_MAX_NAME_LENGTH) == 0) {
4566                 YCHAR local_name[20];
4567                 YCHAR num_string[20];
4568                 YCHAR *x = &num_string[19];
4569                 unsigned v = obj->obj_id;
4570                 num_string[19] = 0;
4571                 while (v > 0) {
4572                         x--;
4573                         *x = '0' + (v % 10);
4574                         v /= 10;
4575                 }
4576                 /* make up a name */
4577                 strcpy(local_name, YAFFS_LOSTNFOUND_PREFIX);
4578                 strcat(local_name, x);
4579                 strncpy(name, local_name, buffer_size - 1);
4580         }
4581 }
4582
4583 int yaffs_get_obj_name(struct yaffs_obj *obj, YCHAR * name, int buffer_size)
4584 {
4585         memset(name, 0, buffer_size * sizeof(YCHAR));
4586
4587         yaffs_check_obj_details_loaded(obj);
4588
4589         if (obj->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4590                 strncpy(name, YAFFS_LOSTNFOUND_NAME, buffer_size - 1);
4591         }
4592 #ifndef CONFIG_YAFFS_NO_SHORT_NAMES
4593         else if (obj->short_name[0]) {
4594                 strcpy(name, obj->short_name);
4595         }
4596 #endif
4597         else if (obj->hdr_chunk > 0) {
4598                 int result;
4599                 u8 *buffer = yaffs_get_temp_buffer(obj->my_dev, __LINE__);
4600
4601                 struct yaffs_obj_hdr *oh = (struct yaffs_obj_hdr *)buffer;
4602
4603                 memset(buffer, 0, obj->my_dev->data_bytes_per_chunk);
4604
4605                 if (obj->hdr_chunk > 0) {
4606                         result = yaffs_rd_chunk_tags_nand(obj->my_dev,
4607                                                           obj->hdr_chunk,
4608                                                           buffer, NULL);
4609                 }
4610                 yaffs_load_name_from_oh(obj->my_dev, name, oh->name,
4611                                         buffer_size);
4612
4613                 yaffs_release_temp_buffer(obj->my_dev, buffer, __LINE__);
4614         }
4615
4616         yaffs_fix_null_name(obj, name, buffer_size);
4617
4618         return strnlen(name, YAFFS_MAX_NAME_LENGTH);
4619 }
4620
4621 int yaffs_get_obj_length(struct yaffs_obj *obj)
4622 {
4623         /* Dereference any hard linking */
4624         obj = yaffs_get_equivalent_obj(obj);
4625
4626         if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
4627                 return obj->variant.file_variant.file_size;
4628         if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
4629                 if (!obj->variant.symlink_variant.alias)
4630                         return 0;
4631                 return strnlen(obj->variant.symlink_variant.alias,
4632                                      YAFFS_MAX_ALIAS_LENGTH);
4633         } else {
4634                 /* Only a directory should drop through to here */
4635                 return obj->my_dev->data_bytes_per_chunk;
4636         }
4637 }
4638
4639 int yaffs_get_obj_link_count(struct yaffs_obj *obj)
4640 {
4641         int count = 0;
4642         struct list_head *i;
4643
4644         if (!obj->unlinked)
4645                 count++;        /* the object itself */
4646
4647         list_for_each(i, &obj->hard_links)
4648             count++;            /* add the hard links; */
4649
4650         return count;
4651 }
4652
4653 int yaffs_get_obj_inode(struct yaffs_obj *obj)
4654 {
4655         obj = yaffs_get_equivalent_obj(obj);
4656
4657         return obj->obj_id;
4658 }
4659
4660 unsigned yaffs_get_obj_type(struct yaffs_obj *obj)
4661 {
4662         obj = yaffs_get_equivalent_obj(obj);
4663
4664         switch (obj->variant_type) {
4665         case YAFFS_OBJECT_TYPE_FILE:
4666                 return DT_REG;
4667                 break;
4668         case YAFFS_OBJECT_TYPE_DIRECTORY:
4669                 return DT_DIR;
4670                 break;
4671         case YAFFS_OBJECT_TYPE_SYMLINK:
4672                 return DT_LNK;
4673                 break;
4674         case YAFFS_OBJECT_TYPE_HARDLINK:
4675                 return DT_REG;
4676                 break;
4677         case YAFFS_OBJECT_TYPE_SPECIAL:
4678                 if (S_ISFIFO(obj->yst_mode))
4679                         return DT_FIFO;
4680                 if (S_ISCHR(obj->yst_mode))
4681                         return DT_CHR;
4682                 if (S_ISBLK(obj->yst_mode))
4683                         return DT_BLK;
4684                 if (S_ISSOCK(obj->yst_mode))
4685                         return DT_SOCK;
4686         default:
4687                 return DT_REG;
4688                 break;
4689         }
4690 }
4691
4692 YCHAR *yaffs_get_symlink_alias(struct yaffs_obj *obj)
4693 {
4694         obj = yaffs_get_equivalent_obj(obj);
4695         if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK)
4696                 return yaffs_clone_str(obj->variant.symlink_variant.alias);
4697         else
4698                 return yaffs_clone_str(_Y(""));
4699 }
4700
4701 /*--------------------------- Initialisation code -------------------------- */
4702
4703 static int yaffs_check_dev_fns(const struct yaffs_dev *dev)
4704 {
4705
4706         /* Common functions, gotta have */
4707         if (!dev->param.erase_fn || !dev->param.initialise_flash_fn)
4708                 return 0;
4709
4710 #ifdef CONFIG_YAFFS_YAFFS2
4711
4712         /* Can use the "with tags" style interface for yaffs1 or yaffs2 */
4713         if (dev->param.write_chunk_tags_fn &&
4714             dev->param.read_chunk_tags_fn &&
4715             !dev->param.write_chunk_fn &&
4716             !dev->param.read_chunk_fn &&
4717             dev->param.bad_block_fn && dev->param.query_block_fn)
4718                 return 1;
4719 #endif
4720
4721         /* Can use the "spare" style interface for yaffs1 */
4722         if (!dev->param.is_yaffs2 &&
4723             !dev->param.write_chunk_tags_fn &&
4724             !dev->param.read_chunk_tags_fn &&
4725             dev->param.write_chunk_fn &&
4726             dev->param.read_chunk_fn &&
4727             !dev->param.bad_block_fn && !dev->param.query_block_fn)
4728                 return 1;
4729
4730         return 0;               /* bad */
4731 }
4732
4733 static int yaffs_create_initial_dir(struct yaffs_dev *dev)
4734 {
4735         /* Initialise the unlinked, deleted, root and lost and found directories */
4736
4737         dev->lost_n_found = dev->root_dir = NULL;
4738         dev->unlinked_dir = dev->del_dir = NULL;
4739
4740         dev->unlinked_dir =
4741             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
4742
4743         dev->del_dir =
4744             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
4745
4746         dev->root_dir =
4747             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_ROOT,
4748                                   YAFFS_ROOT_MODE | S_IFDIR);
4749         dev->lost_n_found =
4750             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_LOSTNFOUND,
4751                                   YAFFS_LOSTNFOUND_MODE | S_IFDIR);
4752
4753         if (dev->lost_n_found && dev->root_dir && dev->unlinked_dir
4754             && dev->del_dir) {
4755                 yaffs_add_obj_to_dir(dev->root_dir, dev->lost_n_found);
4756                 return YAFFS_OK;
4757         }
4758
4759         return YAFFS_FAIL;
4760 }
4761
4762 int yaffs_guts_initialise(struct yaffs_dev *dev)
4763 {
4764         int init_failed = 0;
4765         unsigned x;
4766         int bits;
4767
4768         yaffs_trace(YAFFS_TRACE_TRACING, "yaffs: yaffs_guts_initialise()" );
4769
4770         /* Check stuff that must be set */
4771
4772         if (!dev) {
4773                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4774                         "yaffs: Need a device"
4775                         );
4776                 return YAFFS_FAIL;
4777         }
4778
4779         dev->internal_start_block = dev->param.start_block;
4780         dev->internal_end_block = dev->param.end_block;
4781         dev->block_offset = 0;
4782         dev->chunk_offset = 0;
4783         dev->n_free_chunks = 0;
4784
4785         dev->gc_block = 0;
4786
4787         if (dev->param.start_block == 0) {
4788                 dev->internal_start_block = dev->param.start_block + 1;
4789                 dev->internal_end_block = dev->param.end_block + 1;
4790                 dev->block_offset = 1;
4791                 dev->chunk_offset = dev->param.chunks_per_block;
4792         }
4793
4794         /* Check geometry parameters. */
4795
4796         if ((!dev->param.inband_tags && dev->param.is_yaffs2 &&
4797                 dev->param.total_bytes_per_chunk < 1024) ||
4798                 (!dev->param.is_yaffs2 &&
4799                         dev->param.total_bytes_per_chunk < 512) ||
4800                 (dev->param.inband_tags && !dev->param.is_yaffs2) ||
4801                  dev->param.chunks_per_block < 2 ||
4802                  dev->param.n_reserved_blocks < 2 ||
4803                 dev->internal_start_block <= 0 ||
4804                 dev->internal_end_block <= 0 ||
4805                 dev->internal_end_block <=
4806                 (dev->internal_start_block + dev->param.n_reserved_blocks + 2)
4807                 ) {
4808                 /* otherwise it is too small */
4809                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4810                         "NAND geometry problems: chunk size %d, type is yaffs%s, inband_tags %d ",
4811                         dev->param.total_bytes_per_chunk,
4812                         dev->param.is_yaffs2 ? "2" : "",
4813                         dev->param.inband_tags);
4814                 return YAFFS_FAIL;
4815         }
4816
4817         if (yaffs_init_nand(dev) != YAFFS_OK) {
4818                 yaffs_trace(YAFFS_TRACE_ALWAYS, "InitialiseNAND failed");
4819                 return YAFFS_FAIL;
4820         }
4821
4822         /* Sort out space for inband tags, if required */
4823         if (dev->param.inband_tags)
4824                 dev->data_bytes_per_chunk =
4825                     dev->param.total_bytes_per_chunk -
4826                     sizeof(struct yaffs_packed_tags2_tags_only);
4827         else
4828                 dev->data_bytes_per_chunk = dev->param.total_bytes_per_chunk;
4829
4830         /* Got the right mix of functions? */
4831         if (!yaffs_check_dev_fns(dev)) {
4832                 /* Function missing */
4833                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4834                         "device function(s) missing or wrong");
4835
4836                 return YAFFS_FAIL;
4837         }
4838
4839         if (dev->is_mounted) {
4840                 yaffs_trace(YAFFS_TRACE_ALWAYS, "device already mounted");
4841                 return YAFFS_FAIL;
4842         }
4843
4844         /* Finished with most checks. One or two more checks happen later on too. */
4845
4846         dev->is_mounted = 1;
4847
4848         /* OK now calculate a few things for the device */
4849
4850         /*
4851          *  Calculate all the chunk size manipulation numbers:
4852          */
4853         x = dev->data_bytes_per_chunk;
4854         /* We always use dev->chunk_shift and dev->chunk_div */
4855         dev->chunk_shift = calc_shifts(x);
4856         x >>= dev->chunk_shift;
4857         dev->chunk_div = x;
4858         /* We only use chunk mask if chunk_div is 1 */
4859         dev->chunk_mask = (1 << dev->chunk_shift) - 1;
4860
4861         /*
4862          * Calculate chunk_grp_bits.
4863          * We need to find the next power of 2 > than internal_end_block
4864          */
4865
4866         x = dev->param.chunks_per_block * (dev->internal_end_block + 1);
4867
4868         bits = calc_shifts_ceiling(x);
4869
4870         /* Set up tnode width if wide tnodes are enabled. */
4871         if (!dev->param.wide_tnodes_disabled) {
4872                 /* bits must be even so that we end up with 32-bit words */
4873                 if (bits & 1)
4874                         bits++;
4875                 if (bits < 16)
4876                         dev->tnode_width = 16;
4877                 else
4878                         dev->tnode_width = bits;
4879         } else {
4880                 dev->tnode_width = 16;
4881         }
4882
4883         dev->tnode_mask = (1 << dev->tnode_width) - 1;
4884
4885         /* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
4886          * so if the bitwidth of the
4887          * chunk range we're using is greater than 16 we need
4888          * to figure out chunk shift and chunk_grp_size
4889          */
4890
4891         if (bits <= dev->tnode_width)
4892                 dev->chunk_grp_bits = 0;
4893         else
4894                 dev->chunk_grp_bits = bits - dev->tnode_width;
4895
4896         dev->tnode_size = (dev->tnode_width * YAFFS_NTNODES_LEVEL0) / 8;
4897         if (dev->tnode_size < sizeof(struct yaffs_tnode))
4898                 dev->tnode_size = sizeof(struct yaffs_tnode);
4899
4900         dev->chunk_grp_size = 1 << dev->chunk_grp_bits;
4901
4902         if (dev->param.chunks_per_block < dev->chunk_grp_size) {
4903                 /* We have a problem because the soft delete won't work if
4904                  * the chunk group size > chunks per block.
4905                  * This can be remedied by using larger "virtual blocks".
4906                  */
4907                 yaffs_trace(YAFFS_TRACE_ALWAYS, "chunk group too large");
4908
4909                 return YAFFS_FAIL;
4910         }
4911
4912         /* OK, we've finished verifying the device, lets continue with initialisation */
4913
4914         /* More device initialisation */
4915         dev->all_gcs = 0;
4916         dev->passive_gc_count = 0;
4917         dev->oldest_dirty_gc_count = 0;
4918         dev->bg_gcs = 0;
4919         dev->gc_block_finder = 0;
4920         dev->buffered_block = -1;
4921         dev->doing_buffered_block_rewrite = 0;
4922         dev->n_deleted_files = 0;
4923         dev->n_bg_deletions = 0;
4924         dev->n_unlinked_files = 0;
4925         dev->n_ecc_fixed = 0;
4926         dev->n_ecc_unfixed = 0;
4927         dev->n_tags_ecc_fixed = 0;
4928         dev->n_tags_ecc_unfixed = 0;
4929         dev->n_erase_failures = 0;
4930         dev->n_erased_blocks = 0;
4931         dev->gc_disable = 0;
4932         dev->has_pending_prioritised_gc = 1;    /* Assume the worst for now, will get fixed on first GC */
4933         INIT_LIST_HEAD(&dev->dirty_dirs);
4934         dev->oldest_dirty_seq = 0;
4935         dev->oldest_dirty_block = 0;
4936
4937         /* Initialise temporary buffers and caches. */
4938         if (!yaffs_init_tmp_buffers(dev))
4939                 init_failed = 1;
4940
4941         dev->cache = NULL;
4942         dev->gc_cleanup_list = NULL;
4943
4944         if (!init_failed && dev->param.n_caches > 0) {
4945                 int i;
4946                 void *buf;
4947                 int cache_bytes =
4948                     dev->param.n_caches * sizeof(struct yaffs_cache);
4949
4950                 if (dev->param.n_caches > YAFFS_MAX_SHORT_OP_CACHES)
4951                         dev->param.n_caches = YAFFS_MAX_SHORT_OP_CACHES;
4952
4953                 dev->cache = kmalloc(cache_bytes, GFP_NOFS);
4954
4955                 buf = (u8 *) dev->cache;
4956
4957                 if (dev->cache)
4958                         memset(dev->cache, 0, cache_bytes);
4959
4960                 for (i = 0; i < dev->param.n_caches && buf; i++) {
4961                         dev->cache[i].object = NULL;
4962                         dev->cache[i].last_use = 0;
4963                         dev->cache[i].dirty = 0;
4964                         dev->cache[i].data = buf =
4965                             kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
4966                 }
4967                 if (!buf)
4968                         init_failed = 1;
4969
4970                 dev->cache_last_use = 0;
4971         }
4972
4973         dev->cache_hits = 0;
4974
4975         if (!init_failed) {
4976                 dev->gc_cleanup_list =
4977                     kmalloc(dev->param.chunks_per_block * sizeof(u32),
4978                                         GFP_NOFS);
4979                 if (!dev->gc_cleanup_list)
4980                         init_failed = 1;
4981         }
4982
4983         if (dev->param.is_yaffs2)
4984                 dev->param.use_header_file_size = 1;
4985
4986         if (!init_failed && !yaffs_init_blocks(dev))
4987                 init_failed = 1;
4988
4989         yaffs_init_tnodes_and_objs(dev);
4990
4991         if (!init_failed && !yaffs_create_initial_dir(dev))
4992                 init_failed = 1;
4993
4994         if (!init_failed) {
4995                 /* Now scan the flash. */
4996                 if (dev->param.is_yaffs2) {
4997                         if (yaffs2_checkpt_restore(dev)) {
4998                                 yaffs_check_obj_details_loaded(dev->root_dir);
4999                                 yaffs_trace(YAFFS_TRACE_CHECKPOINT | YAFFS_TRACE_MOUNT,
5000                                         "yaffs: restored from checkpoint"
5001                                         );
5002                         } else {
5003
5004                                 /* Clean up the mess caused by an aborted checkpoint load
5005                                  * and scan backwards.
5006                                  */
5007                                 yaffs_deinit_blocks(dev);
5008
5009                                 yaffs_deinit_tnodes_and_objs(dev);
5010
5011                                 dev->n_erased_blocks = 0;
5012                                 dev->n_free_chunks = 0;
5013                                 dev->alloc_block = -1;
5014                                 dev->alloc_page = -1;
5015                                 dev->n_deleted_files = 0;
5016                                 dev->n_unlinked_files = 0;
5017                                 dev->n_bg_deletions = 0;
5018
5019                                 if (!init_failed && !yaffs_init_blocks(dev))
5020                                         init_failed = 1;
5021
5022                                 yaffs_init_tnodes_and_objs(dev);
5023
5024                                 if (!init_failed
5025                                     && !yaffs_create_initial_dir(dev))
5026                                         init_failed = 1;
5027
5028                                 if (!init_failed && !yaffs2_scan_backwards(dev))
5029                                         init_failed = 1;
5030                         }
5031                 } else if (!yaffs1_scan(dev)) {
5032                         init_failed = 1;
5033                 }
5034
5035                 yaffs_strip_deleted_objs(dev);
5036                 yaffs_fix_hanging_objs(dev);
5037                 if (dev->param.empty_lost_n_found)
5038                         yaffs_empty_l_n_f(dev);
5039         }
5040
5041         if (init_failed) {
5042                 /* Clean up the mess */
5043                 yaffs_trace(YAFFS_TRACE_TRACING,
5044                   "yaffs: yaffs_guts_initialise() aborted.");
5045
5046                 yaffs_deinitialise(dev);
5047                 return YAFFS_FAIL;
5048         }
5049
5050         /* Zero out stats */
5051         dev->n_page_reads = 0;
5052         dev->n_page_writes = 0;
5053         dev->n_erasures = 0;
5054         dev->n_gc_copies = 0;
5055         dev->n_retired_writes = 0;
5056
5057         dev->n_retired_blocks = 0;
5058
5059         yaffs_verify_free_chunks(dev);
5060         yaffs_verify_blocks(dev);
5061
5062         /* Clean up any aborted checkpoint data */
5063         if (!dev->is_checkpointed && dev->blocks_in_checkpt > 0)
5064                 yaffs2_checkpt_invalidate(dev);
5065
5066         yaffs_trace(YAFFS_TRACE_TRACING,
5067           "yaffs: yaffs_guts_initialise() done.");
5068         return YAFFS_OK;
5069
5070 }
5071
5072 void yaffs_deinitialise(struct yaffs_dev *dev)
5073 {
5074         if (dev->is_mounted) {
5075                 int i;
5076
5077                 yaffs_deinit_blocks(dev);
5078                 yaffs_deinit_tnodes_and_objs(dev);
5079                 if (dev->param.n_caches > 0 && dev->cache) {
5080
5081                         for (i = 0; i < dev->param.n_caches; i++) {
5082                                 if (dev->cache[i].data)
5083                                         kfree(dev->cache[i].data);
5084                                 dev->cache[i].data = NULL;
5085                         }
5086
5087                         kfree(dev->cache);
5088                         dev->cache = NULL;
5089                 }
5090
5091                 kfree(dev->gc_cleanup_list);
5092
5093                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
5094                         kfree(dev->temp_buffer[i].buffer);
5095
5096                 dev->is_mounted = 0;
5097
5098                 if (dev->param.deinitialise_flash_fn)
5099                         dev->param.deinitialise_flash_fn(dev);
5100         }
5101 }
5102
5103 int yaffs_count_free_chunks(struct yaffs_dev *dev)
5104 {
5105         int n_free = 0;
5106         int b;
5107
5108         struct yaffs_block_info *blk;
5109
5110         blk = dev->block_info;
5111         for (b = dev->internal_start_block; b <= dev->internal_end_block; b++) {
5112                 switch (blk->block_state) {
5113                 case YAFFS_BLOCK_STATE_EMPTY:
5114                 case YAFFS_BLOCK_STATE_ALLOCATING:
5115                 case YAFFS_BLOCK_STATE_COLLECTING:
5116                 case YAFFS_BLOCK_STATE_FULL:
5117                         n_free +=
5118                             (dev->param.chunks_per_block - blk->pages_in_use +
5119                              blk->soft_del_pages);
5120                         break;
5121                 default:
5122                         break;
5123                 }
5124                 blk++;
5125         }
5126
5127         return n_free;
5128 }
5129
5130 int yaffs_get_n_free_chunks(struct yaffs_dev *dev)
5131 {
5132         /* This is what we report to the outside world */
5133
5134         int n_free;
5135         int n_dirty_caches;
5136         int blocks_for_checkpt;
5137         int i;
5138
5139         n_free = dev->n_free_chunks;
5140         n_free += dev->n_deleted_files;
5141
5142         /* Now count the number of dirty chunks in the cache and subtract those */
5143
5144         for (n_dirty_caches = 0, i = 0; i < dev->param.n_caches; i++) {
5145                 if (dev->cache[i].dirty)
5146                         n_dirty_caches++;
5147         }
5148
5149         n_free -= n_dirty_caches;
5150
5151         n_free -=
5152             ((dev->param.n_reserved_blocks + 1) * dev->param.chunks_per_block);
5153
5154         /* Now we figure out how much to reserve for the checkpoint and report that... */
5155         blocks_for_checkpt = yaffs_calc_checkpt_blocks_required(dev);
5156
5157         n_free -= (blocks_for_checkpt * dev->param.chunks_per_block);
5158
5159         if (n_free < 0)
5160                 n_free = 0;
5161
5162         return n_free;
5163
5164 }