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 #include "yportenv.h"
  14 #include "yaffs_trace.h"
  15
  16 #include "yaffsinterface.h"
  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 /* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
  37 #define YAFFS_GC_GOOD_ENOUGH 2
  38 #define YAFFS_GC_PASSIVE_THRESHOLD 4
  39
  40 #include "yaffs_ecc.h"
  41
  42
  43
  44 /* Robustification (if it ever comes about...) */
  45 static void yaffs_retire_block(yaffs_dev_t *dev, int flash_block);
  46 static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk,
  47                 int erasedOk);
  48 static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
  49                                 const __u8 *data,
  50                                 const yaffs_ext_tags *tags);
  51 static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
  52                                 const yaffs_ext_tags *tags);
  53
  54 /* Other local prototypes */
  55 static void yaffs_update_parent(yaffs_obj_t *obj);
  56 static int yaffs_unlink_obj(yaffs_obj_t *obj);
  57 static int yaffs_obj_cache_dirty(yaffs_obj_t *obj);
  58
  59 static int yaffs_write_new_chunk(yaffs_dev_t *dev,
  60                                         const __u8 *buffer,
  61                                         yaffs_ext_tags *tags,
  62                                         int useReserve);
  63
  64
  65 static yaffs_obj_t *yaffs_new_obj(yaffs_dev_t *dev, int number,
  66                                         yaffs_obj_type type);
  67
  68
  69 static int yaffs_apply_xattrib_mod(yaffs_obj_t *obj, char *buffer, yaffs_xattr_mod *xmod);
  70
  71 static void yaffs_remove_obj_from_dir(yaffs_obj_t *obj);
  72 static int yaffs_check_structures(void);
  73 static int yaffs_generic_obj_del(yaffs_obj_t *in);
  74
  75 static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev,
  76                                 int nand_chunk);
  77
  78 static int yaffs_unlink_worker(yaffs_obj_t *obj);
  79
  80 static int yaffs_tags_match(const yaffs_ext_tags *tags, int obj_id,
  81                         int chunkInObject);
  82
  83 static int yaffs_alloc_chunk(yaffs_dev_t *dev, int useReserve,
  84                                 yaffs_block_info_t **blockUsedPtr);
  85
  86 static void yaffs_check_obj_details_loaded(yaffs_obj_t *in);
  87
  88 static void yaffs_invalidate_whole_cache(yaffs_obj_t *in);
  89 static void yaffs_invalidate_chunk_cache(yaffs_obj_t *object, int chunk_id);
  90
  91 static int yaffs_find_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
  92                                 yaffs_ext_tags *tags);
  93
  94 static int yaffs_verify_chunk_written(yaffs_dev_t *dev,
  95                                         int nand_chunk,
  96                                         const __u8 *data,
  97                                         yaffs_ext_tags *tags);
  98
  99
 100 static void yaffs_load_name_from_oh(yaffs_dev_t *dev,YCHAR *name, const YCHAR *ohName, int bufferSize);
 101 static void yaffs_load_oh_from_name(yaffs_dev_t *dev,YCHAR *ohName, const YCHAR *name);
 102
 103
 104 /* Function to calculate chunk and offset */
 105
 106 static void yaffs_addr_to_chunk(yaffs_dev_t *dev, loff_t addr, int *chunkOut,
 107                 __u32 *offsetOut)
 108 {
 109         int chunk;
 110         __u32 offset;
 111
 112         chunk  = (__u32)(addr >> dev->chunk_shift);
 113
 114         if (dev->chunk_div == 1) {
 115                 /* easy power of 2 case */
 116                 offset = (__u32)(addr & dev->chunk_mask);
 117         } else {
 118                 /* Non power-of-2 case */
 119
 120                 loff_t chunkBase;
 121
 122                 chunk /= dev->chunk_div;
 123
 124                 chunkBase = ((loff_t)chunk) * dev->data_bytes_per_chunk;
 125                 offset = (__u32)(addr - chunkBase);
 126         }
 127
 128         *chunkOut = chunk;
 129         *offsetOut = offset;
 130 }
 131
 132 /* Function to return the number of shifts for a power of 2 greater than or
 133  * equal to the given number
 134  * Note we don't try to cater for all possible numbers and this does not have to
 135  * be hellishly efficient.
 136  */
 137
 138 static __u32 ShiftsGE(__u32 x)
 139 {
 140         int extraBits;
 141         int nShifts;
 142
 143         nShifts = extraBits = 0;
 144
 145         while (x > 1) {
 146                 if (x & 1)
 147                         extraBits++;
 148                 x >>= 1;
 149                 nShifts++;
 150         }
 151
 152         if (extraBits)
 153                 nShifts++;
 154
 155         return nShifts;
 156 }
 157
 158 /* Function to return the number of shifts to get a 1 in bit 0
 159  */
 160
 161 static __u32 Shifts(__u32 x)
 162 {
 163         __u32 nShifts;
 164
 165         nShifts =  0;
 166
 167         if (!x)
 168                 return 0;
 169
 170         while (!(x&1)) {
 171                 x >>= 1;
 172                 nShifts++;
 173         }
 174
 175         return nShifts;
 176 }
 177
 178
 179
 180 /*
 181  * Temporary buffer manipulations.
 182  */
 183
 184 static int yaffs_init_tmp_buffers(yaffs_dev_t *dev)
 185 {
 186         int i;
 187         __u8 *buf = (__u8 *)1;
 188
 189         memset(dev->temp_buffer, 0, sizeof(dev->temp_buffer));
 190
 191         for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
 192                 dev->temp_buffer[i].line = 0;   /* not in use */
 193                 dev->temp_buffer[i].buffer = buf =
 194                     YMALLOC_DMA(dev->param.total_bytes_per_chunk);
 195         }
 196
 197         return buf ? YAFFS_OK : YAFFS_FAIL;
 198 }
 199
 200 __u8 *yaffs_get_temp_buffer(yaffs_dev_t *dev, int line_no)
 201 {
 202         int i, j;
 203
 204         dev->temp_in_use++;
 205         if (dev->temp_in_use > dev->max_temp)
 206                 dev->max_temp = dev->temp_in_use;
 207
 208         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 209                 if (dev->temp_buffer[i].line == 0) {
 210                         dev->temp_buffer[i].line = line_no;
 211                         if ((i + 1) > dev->max_temp) {
 212                                 dev->max_temp = i + 1;
 213                                 for (j = 0; j <= i; j++)
 214                                         dev->temp_buffer[j].max_line =
 215                                             dev->temp_buffer[j].line;
 216                         }
 217
 218                         return dev->temp_buffer[i].buffer;
 219                 }
 220         }
 221
 222         T(YAFFS_TRACE_BUFFERS,
 223           (TSTR("Out of temp buffers at line %d, other held by lines:"),
 224            line_no));
 225         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
 226                 T(YAFFS_TRACE_BUFFERS, (TSTR(" %d "), dev->temp_buffer[i].line));
 227
 228         T(YAFFS_TRACE_BUFFERS, (TSTR(" " TENDSTR)));
 229
 230         /*
 231          * If we got here then we have to allocate an unmanaged one
 232          * This is not good.
 233          */
 234
 235         dev->unmanaged_buffer_allocs++;
 236         return YMALLOC(dev->data_bytes_per_chunk);
 237
 238 }
 239
 240 void yaffs_release_temp_buffer(yaffs_dev_t *dev, __u8 *buffer,
 241                                     int line_no)
 242 {
 243         int i;
 244
 245         dev->temp_in_use--;
 246
 247         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 248                 if (dev->temp_buffer[i].buffer == buffer) {
 249                         dev->temp_buffer[i].line = 0;
 250                         return;
 251                 }
 252         }
 253
 254         if (buffer) {
 255                 /* assume it is an unmanaged one. */
 256                 T(YAFFS_TRACE_BUFFERS,
 257                   (TSTR("Releasing unmanaged temp buffer in line %d" TENDSTR),
 258                    line_no));
 259                 YFREE(buffer);
 260                 dev->unmanaged_buffer_deallocs++;
 261         }
 262
 263 }
 264
 265 /*
 266  * Determine if we have a managed buffer.
 267  */
 268 int yaffs_is_managed_tmp_buffer(yaffs_dev_t *dev, const __u8 *buffer)
 269 {
 270         int i;
 271
 272         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 273                 if (dev->temp_buffer[i].buffer == buffer)
 274                         return 1;
 275         }
 276
 277         for (i = 0; i < dev->param.n_caches; i++) {
 278                 if (dev->cache[i].data == buffer)
 279                         return 1;
 280         }
 281
 282         if (buffer == dev->checkpt_buffer)
 283                 return 1;
 284
 285         T(YAFFS_TRACE_ALWAYS,
 286                 (TSTR("yaffs: unmaged buffer detected.\n" TENDSTR)));
 287         return 0;
 288 }
 289
 290 /*
 291  * Verification code
 292  */
 293
 294
 295
 296
 297 /*
 298  *  Simple hash function. Needs to have a reasonable spread
 299  */
 300
 301 static Y_INLINE int yaffs_hash_fn(int n)
 302 {
 303         n = abs(n);
 304         return n % YAFFS_NOBJECT_BUCKETS;
 305 }
 306
 307 /*
 308  * Access functions to useful fake objects.
 309  * Note that root might have a presence in NAND if permissions are set.
 310  */
 311
 312 yaffs_obj_t *yaffs_root(yaffs_dev_t *dev)
 313 {
 314         return dev->root_dir;
 315 }
 316
 317 yaffs_obj_t *yaffs_lost_n_found(yaffs_dev_t *dev)
 318 {
 319         return dev->lost_n_found;
 320 }
 321
 322
 323 /*
 324  *  Erased NAND checking functions
 325  */
 326
 327 int yaffs_check_ff(__u8 *buffer, int n_bytes)
 328 {
 329         /* Horrible, slow implementation */
 330         while (n_bytes--) {
 331                 if (*buffer != 0xFF)
 332                         return 0;
 333                 buffer++;
 334         }
 335         return 1;
 336 }
 337
 338 static int yaffs_check_chunk_erased(struct yaffs_dev_s *dev,
 339                                 int nand_chunk)
 340 {
 341         int retval = YAFFS_OK;
 342         __u8 *data = yaffs_get_temp_buffer(dev, __LINE__);
 343         yaffs_ext_tags tags;
 344         int result;
 345
 346         result = yaffs_rd_chunk_tags_nand(dev, nand_chunk, data, &tags);
 347
 348         if (tags.ecc_result > YAFFS_ECC_RESULT_NO_ERROR)
 349                 retval = YAFFS_FAIL;
 350
 351         if (!yaffs_check_ff(data, dev->data_bytes_per_chunk) || tags.chunk_used) {
 352                 T(YAFFS_TRACE_NANDACCESS,
 353                   (TSTR("Chunk %d not erased" TENDSTR), nand_chunk));
 354                 retval = YAFFS_FAIL;
 355         }
 356
 357         yaffs_release_temp_buffer(dev, data, __LINE__);
 358
 359         return retval;
 360
 361 }
 362
 363
 364 static int yaffs_verify_chunk_written(yaffs_dev_t *dev,
 365                                         int nand_chunk,
 366                                         const __u8 *data,
 367                                         yaffs_ext_tags *tags)
 368 {
 369         int retval = YAFFS_OK;
 370         yaffs_ext_tags tempTags;
 371         __u8 *buffer = yaffs_get_temp_buffer(dev,__LINE__);
 372         int result;
 373
 374         result = yaffs_rd_chunk_tags_nand(dev,nand_chunk,buffer,&tempTags);
 375         if(memcmp(buffer,data,dev->data_bytes_per_chunk) ||
 376                 tempTags.obj_id != tags->obj_id ||
 377                 tempTags.chunk_id  != tags->chunk_id ||
 378                 tempTags.n_bytes != tags->n_bytes)
 379                 retval = YAFFS_FAIL;
 380
 381         yaffs_release_temp_buffer(dev, buffer, __LINE__);
 382
 383         return retval;
 384 }
 385
 386 static int yaffs_write_new_chunk(struct yaffs_dev_s *dev,
 387                                         const __u8 *data,
 388                                         yaffs_ext_tags *tags,
 389                                         int useReserve)
 390 {
 391         int attempts = 0;
 392         int writeOk = 0;
 393         int chunk;
 394
 395         yaffs2_checkpt_invalidate(dev);
 396
 397         do {
 398                 yaffs_block_info_t *bi = 0;
 399                 int erasedOk = 0;
 400
 401                 chunk = yaffs_alloc_chunk(dev, useReserve, &bi);
 402                 if (chunk < 0) {
 403                         /* no space */
 404                         break;
 405                 }
 406
 407                 /* First check this chunk is erased, if it needs
 408                  * checking.  The checking policy (unless forced
 409                  * always on) is as follows:
 410                  *
 411                  * Check the first page we try to write in a block.
 412                  * If the check passes then we don't need to check any
 413                  * more.        If the check fails, we check again...
 414                  * If the block has been erased, we don't need to check.
 415                  *
 416                  * However, if the block has been prioritised for gc,
 417                  * then we think there might be something odd about
 418                  * this block and stop using it.
 419                  *
 420                  * Rationale: We should only ever see chunks that have
 421                  * not been erased if there was a partially written
 422                  * chunk due to power loss.  This checking policy should
 423                  * catch that case with very few checks and thus save a
 424                  * lot of checks that are most likely not needed.
 425                  *
 426                  * Mods to the above
 427                  * If an erase check fails or the write fails we skip the
 428                  * rest of the block.
 429                  */
 430
 431                 /* let's give it a try */
 432                 attempts++;
 433
 434                 if(dev->param.always_check_erased)
 435                         bi->skip_erased_check = 0;
 436
 437                 if (!bi->skip_erased_check) {
 438                         erasedOk = yaffs_check_chunk_erased(dev, chunk);
 439                         if (erasedOk != YAFFS_OK) {
 440                                 T(YAFFS_TRACE_ERROR,
 441                                 (TSTR("**>> yaffs chunk %d was not erased"
 442                                 TENDSTR), chunk));
 443
 444                                 /* If not erased, delete this one,
 445                                  * skip rest of block and
 446                                  * try another chunk */
 447                                  yaffs_chunk_del(dev,chunk,1,__LINE__);
 448                                  yaffs_skip_rest_of_block(dev);
 449                                 continue;
 450                         }
 451                 }
 452
 453                 writeOk = yaffs_wr_chunk_tags_nand(dev, chunk,
 454                                 data, tags);
 455
 456                 if(!bi->skip_erased_check)
 457                         writeOk = yaffs_verify_chunk_written(dev, chunk, data, tags);
 458
 459                 if (writeOk != YAFFS_OK) {
 460                         /* Clean up aborted write, skip to next block and
 461                          * try another chunk */
 462                         yaffs_handle_chunk_wr_error(dev, chunk, erasedOk);
 463                         continue;
 464                 }
 465
 466                 bi->skip_erased_check = 1;
 467
 468                 /* Copy the data into the robustification buffer */
 469                 yaffs_handle_chunk_wr_ok(dev, chunk, data, tags);
 470
 471         } while (writeOk != YAFFS_OK &&
 472                 (yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
 473
 474         if (!writeOk)
 475                 chunk = -1;
 476
 477         if (attempts > 1) {
 478                 T(YAFFS_TRACE_ERROR,
 479                         (TSTR("**>> yaffs write required %d attempts" TENDSTR),
 480                         attempts));
 481
 482                 dev->n_retired_writes += (attempts - 1);
 483         }
 484
 485         return chunk;
 486 }
 487
 488
 489
 490 /*
 491  * Block retiring for handling a broken block.
 492  */
 493
 494 static void yaffs_retire_block(yaffs_dev_t *dev, int flash_block)
 495 {
 496         yaffs_block_info_t *bi = yaffs_get_block_info(dev, flash_block);
 497
 498         yaffs2_checkpt_invalidate(dev);
 499
 500         yaffs2_clear_oldest_dirty_seq(dev,bi);
 501
 502         if (yaffs_mark_bad(dev, flash_block) != YAFFS_OK) {
 503                 if (yaffs_erase_block(dev, flash_block) != YAFFS_OK) {
 504                         T(YAFFS_TRACE_ALWAYS, (TSTR(
 505                                 "yaffs: Failed to mark bad and erase block %d"
 506                                 TENDSTR), flash_block));
 507                 } else {
 508                         yaffs_ext_tags tags;
 509                         int chunk_id = flash_block * dev->param.chunks_per_block;
 510
 511                         __u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
 512
 513                         memset(buffer, 0xff, dev->data_bytes_per_chunk);
 514                         yaffs_init_tags(&tags);
 515                         tags.seq_number = YAFFS_SEQUENCE_BAD_BLOCK;
 516                         if (dev->param.write_chunk_tags_fn(dev, chunk_id -
 517                                 dev->chunk_offset, buffer, &tags) != YAFFS_OK)
 518                                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Failed to "
 519                                         TCONT("write bad block marker to block %d")
 520                                         TENDSTR), flash_block));
 521
 522                         yaffs_release_temp_buffer(dev, buffer, __LINE__);
 523                 }
 524         }
 525
 526         bi->block_state = YAFFS_BLOCK_STATE_DEAD;
 527         bi->gc_prioritise = 0;
 528         bi->needs_retiring = 0;
 529
 530         dev->n_retired_blocks++;
 531 }
 532
 533 /*
 534  * Functions for robustisizing TODO
 535  *
 536  */
 537
 538 static void yaffs_handle_chunk_wr_ok(yaffs_dev_t *dev, int nand_chunk,
 539                                 const __u8 *data,
 540                                 const yaffs_ext_tags *tags)
 541 {
 542         dev=dev;
 543         nand_chunk=nand_chunk;
 544         data=data;
 545         tags=tags;
 546 }
 547
 548 static void yaffs_handle_chunk_update(yaffs_dev_t *dev, int nand_chunk,
 549                                 const yaffs_ext_tags *tags)
 550 {
 551         dev=dev;
 552         nand_chunk=nand_chunk;
 553         tags=tags;
 554 }
 555
 556 void yaffs_handle_chunk_error(yaffs_dev_t *dev, yaffs_block_info_t *bi)
 557 {
 558         if (!bi->gc_prioritise) {
 559                 bi->gc_prioritise = 1;
 560                 dev->has_pending_prioritised_gc = 1;
 561                 bi->chunk_error_strikes++;
 562
 563                 if (bi->chunk_error_strikes > 3) {
 564                         bi->needs_retiring = 1; /* Too many stikes, so retire this */
 565                         T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Block struck out" TENDSTR)));
 566
 567                 }
 568         }
 569 }
 570
 571 static void yaffs_handle_chunk_wr_error(yaffs_dev_t *dev, int nand_chunk,
 572                 int erasedOk)
 573 {
 574         int flash_block = nand_chunk / dev->param.chunks_per_block;
 575         yaffs_block_info_t *bi = yaffs_get_block_info(dev, flash_block);
 576
 577         yaffs_handle_chunk_error(dev, bi);
 578
 579         if (erasedOk) {
 580                 /* Was an actual write failure, so mark the block for retirement  */
 581                 bi->needs_retiring = 1;
 582                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
 583                   (TSTR("**>> Block %d needs retiring" TENDSTR), flash_block));
 584         }
 585
 586         /* Delete the chunk */
 587         yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
 588         yaffs_skip_rest_of_block(dev);
 589 }
 590
 591
 592 /*---------------- Name handling functions ------------*/
 593
 594 static __u16 yaffs_calc_name_sum(const YCHAR *name)
 595 {
 596         __u16 sum = 0;
 597         __u16 i = 1;
 598
 599         const YUCHAR *bname = (const YUCHAR *) name;
 600         if (bname) {
 601                 while ((*bname) && (i < (YAFFS_MAX_NAME_LENGTH/2))) {
 602
 603 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
 604                         sum += yaffs_toupper(*bname) * i;
 605 #else
 606                         sum += (*bname) * i;
 607 #endif
 608                         i++;
 609                         bname++;
 610                 }
 611         }
 612         return sum;
 613 }
 614
 615 void yaffs_set_obj_name(yaffs_obj_t *obj, const YCHAR *name)
 616 {
 617 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
 618         memset(obj->short_name, 0, sizeof(YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1));
 619         if (name && yaffs_strnlen(name,YAFFS_SHORT_NAME_LENGTH+1) <= YAFFS_SHORT_NAME_LENGTH)
 620                 yaffs_strcpy(obj->short_name, name);
 621         else
 622                 obj->short_name[0] = _Y('\0');
 623 #endif
 624         obj->sum = yaffs_calc_name_sum(name);
 625 }
 626
 627 void yaffs_set_obj_name_from_oh(yaffs_obj_t *obj, const yaffs_obj_header *oh)
 628 {
 629 #ifdef CONFIG_YAFFS_AUTO_UNICODE
 630         YCHAR tmpName[YAFFS_MAX_NAME_LENGTH+1];
 631         memset(tmpName,0,sizeof(tmpName));
 632         yaffs_load_name_from_oh(obj->my_dev,tmpName,oh->name,YAFFS_MAX_NAME_LENGTH+1);
 633         yaffs_set_obj_name(obj,tmpName);
 634 #else
 635         yaffs_set_obj_name(obj,oh->name);
 636 #endif
 637 }
 638
 639 /*-------------------- TNODES -------------------
 640
 641  * List of spare tnodes
 642  * The list is hooked together using the first pointer
 643  * in the tnode.
 644  */
 645
 646
 647 yaffs_tnode_t *yaffs_get_tnode(yaffs_dev_t *dev)
 648 {
 649         yaffs_tnode_t *tn = yaffs_alloc_raw_tnode(dev);
 650         if (tn){
 651                 memset(tn, 0, dev->tnode_size);
 652                 dev->n_tnodes++;
 653         }
 654
 655         dev->checkpoint_blocks_required = 0; /* force recalculation*/
 656
 657         return tn;
 658 }
 659
 660 /* FreeTnode frees up a tnode and puts it back on the free list */
 661 static void yaffs_free_tnode(yaffs_dev_t *dev, yaffs_tnode_t *tn)
 662 {
 663         yaffs_free_raw_tnode(dev,tn);
 664         dev->n_tnodes--;
 665         dev->checkpoint_blocks_required = 0; /* force recalculation*/
 666 }
 667
 668 static void yaffs_deinit_tnodes_and_objs(yaffs_dev_t *dev)
 669 {
 670         yaffs_deinit_raw_tnodes_and_objs(dev);
 671         dev->n_obj = 0;
 672         dev->n_tnodes = 0;
 673 }
 674
 675
 676 void yaffs_load_tnode_0(yaffs_dev_t *dev, yaffs_tnode_t *tn, unsigned pos,
 677                 unsigned val)
 678 {
 679         __u32 *map = (__u32 *)tn;
 680         __u32 bitInMap;
 681         __u32 bitInWord;
 682         __u32 wordInMap;
 683         __u32 mask;
 684
 685         pos &= YAFFS_TNODES_LEVEL0_MASK;
 686         val >>= dev->chunk_grp_bits;
 687
 688         bitInMap = pos * dev->tnode_width;
 689         wordInMap = bitInMap / 32;
 690         bitInWord = bitInMap & (32 - 1);
 691
 692         mask = dev->tnode_mask << bitInWord;
 693
 694         map[wordInMap] &= ~mask;
 695         map[wordInMap] |= (mask & (val << bitInWord));
 696
 697         if (dev->tnode_width > (32 - bitInWord)) {
 698                 bitInWord = (32 - bitInWord);
 699                 wordInMap++;;
 700                 mask = dev->tnode_mask >> (/*dev->tnode_width -*/ bitInWord);
 701                 map[wordInMap] &= ~mask;
 702                 map[wordInMap] |= (mask & (val >> bitInWord));
 703         }
 704 }
 705
 706 __u32 yaffs_get_group_base(yaffs_dev_t *dev, yaffs_tnode_t *tn,
 707                 unsigned pos)
 708 {
 709         __u32 *map = (__u32 *)tn;
 710         __u32 bitInMap;
 711         __u32 bitInWord;
 712         __u32 wordInMap;
 713         __u32 val;
 714
 715         pos &= YAFFS_TNODES_LEVEL0_MASK;
 716
 717         bitInMap = pos * dev->tnode_width;
 718         wordInMap = bitInMap / 32;
 719         bitInWord = bitInMap & (32 - 1);
 720
 721         val = map[wordInMap] >> bitInWord;
 722
 723         if      (dev->tnode_width > (32 - bitInWord)) {
 724                 bitInWord = (32 - bitInWord);
 725                 wordInMap++;;
 726                 val |= (map[wordInMap] << bitInWord);
 727         }
 728
 729         val &= dev->tnode_mask;
 730         val <<= dev->chunk_grp_bits;
 731
 732         return val;
 733 }
 734
 735 /* ------------------- End of individual tnode manipulation -----------------*/
 736
 737 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 738  * The look up tree is represented by the top tnode and the number of top_level
 739  * in the tree. 0 means only the level 0 tnode is in the tree.
 740  */
 741
 742 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
 743 yaffs_tnode_t *yaffs_find_tnode_0(yaffs_dev_t *dev,
 744                                         yaffs_file_s *file_struct,
 745                                         __u32 chunk_id)
 746 {
 747         yaffs_tnode_t *tn = file_struct->top;
 748         __u32 i;
 749         int requiredTallness;
 750         int level = file_struct->top_level;
 751
 752         dev=dev;
 753
 754         /* Check sane level and chunk Id */
 755         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
 756                 return NULL;
 757
 758         if (chunk_id > YAFFS_MAX_CHUNK_ID)
 759                 return NULL;
 760
 761         /* First check we're tall enough (ie enough top_level) */
 762
 763         i = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
 764         requiredTallness = 0;
 765         while (i) {
 766                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 767                 requiredTallness++;
 768         }
 769
 770         if (requiredTallness > file_struct->top_level)
 771                 return NULL; /* Not tall enough, so we can't find it */
 772
 773         /* Traverse down to level 0 */
 774         while (level > 0 && tn) {
 775                 tn = tn->internal[(chunk_id >>
 776                         (YAFFS_TNODES_LEVEL0_BITS +
 777                                 (level - 1) *
 778                                 YAFFS_TNODES_INTERNAL_BITS)) &
 779                         YAFFS_TNODES_INTERNAL_MASK];
 780                 level--;
 781         }
 782
 783         return tn;
 784 }
 785
 786 /* AddOrFindLevel0Tnode finds the level 0 tnode if it exists, otherwise first expands the tree.
 787  * This happens in two steps:
 788  *  1. If the tree isn't tall enough, then make it taller.
 789  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 790  *
 791  * Used when modifying the tree.
 792  *
 793  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the specified tn will
 794  *  be plugged into the ttree.
 795  */
 796
 797 yaffs_tnode_t *yaffs_add_find_tnode_0(yaffs_dev_t *dev,
 798                                         yaffs_file_s *file_struct,
 799                                         __u32 chunk_id,
 800                                         yaffs_tnode_t *passed_tn)
 801 {
 802         int requiredTallness;
 803         int i;
 804         int l;
 805         yaffs_tnode_t *tn;
 806
 807         __u32 x;
 808
 809
 810         /* Check sane level and page Id */
 811         if (file_struct->top_level < 0 || file_struct->top_level > YAFFS_TNODES_MAX_LEVEL)
 812                 return NULL;
 813
 814         if (chunk_id > YAFFS_MAX_CHUNK_ID)
 815                 return NULL;
 816
 817         /* First check we're tall enough (ie enough top_level) */
 818
 819         x = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
 820         requiredTallness = 0;
 821         while (x) {
 822                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 823                 requiredTallness++;
 824         }
 825
 826
 827         if (requiredTallness > file_struct->top_level) {
 828                 /* Not tall enough, gotta make the tree taller */
 829                 for (i = file_struct->top_level; i < requiredTallness; i++) {
 830
 831                         tn = yaffs_get_tnode(dev);
 832
 833                         if (tn) {
 834                                 tn->internal[0] = file_struct->top;
 835                                 file_struct->top = tn;
 836                                 file_struct->top_level++;
 837                         } else {
 838                                 T(YAFFS_TRACE_ERROR,
 839                                         (TSTR("yaffs: no more tnodes" TENDSTR)));
 840                                 return NULL;
 841                         }
 842                 }
 843         }
 844
 845         /* Traverse down to level 0, adding anything we need */
 846
 847         l = file_struct->top_level;
 848         tn = file_struct->top;
 849
 850         if (l > 0) {
 851                 while (l > 0 && tn) {
 852                         x = (chunk_id >>
 853                              (YAFFS_TNODES_LEVEL0_BITS +
 854                               (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
 855                             YAFFS_TNODES_INTERNAL_MASK;
 856
 857
 858                         if ((l > 1) && !tn->internal[x]) {
 859                                 /* Add missing non-level-zero tnode */
 860                                 tn->internal[x] = yaffs_get_tnode(dev);
 861                                 if(!tn->internal[x])
 862                                         return NULL;
 863                         } else if (l == 1) {
 864                                 /* Looking from level 1 at level 0 */
 865                                 if (passed_tn) {
 866                                         /* If we already have one, then release it.*/
 867                                         if (tn->internal[x])
 868                                                 yaffs_free_tnode(dev, tn->internal[x]);
 869                                         tn->internal[x] = passed_tn;
 870
 871                                 } else if (!tn->internal[x]) {
 872                                         /* Don't have one, none passed in */
 873                                         tn->internal[x] = yaffs_get_tnode(dev);
 874                                         if(!tn->internal[x])
 875                                                 return NULL;
 876                                 }
 877                         }
 878
 879                         tn = tn->internal[x];
 880                         l--;
 881                 }
 882         } else {
 883                 /* top is level 0 */
 884                 if (passed_tn) {
 885                         memcpy(tn, passed_tn, (dev->tnode_width * YAFFS_NTNODES_LEVEL0)/8);
 886                         yaffs_free_tnode(dev, passed_tn);
 887                 }
 888         }
 889
 890         return tn;
 891 }
 892
 893 static int yaffs_find_chunk_in_group(yaffs_dev_t *dev, int theChunk,
 894                                 yaffs_ext_tags *tags, int obj_id,
 895                                 int inode_chunk)
 896 {
 897         int j;
 898
 899         for (j = 0; theChunk && j < dev->chunk_grp_size; j++) {
 900                 if (yaffs_check_chunk_bit(dev, theChunk / dev->param.chunks_per_block,
 901                                 theChunk % dev->param.chunks_per_block)) {
 902
 903                         if(dev->chunk_grp_size == 1)
 904                                 return theChunk;
 905                         else {
 906                                 yaffs_rd_chunk_tags_nand(dev, theChunk, NULL,
 907                                                                 tags);
 908                                 if (yaffs_tags_match(tags, obj_id, inode_chunk)) {
 909                                         /* found it; */
 910                                         return theChunk;
 911                                 }
 912                         }
 913                 }
 914                 theChunk++;
 915         }
 916         return -1;
 917 }
 918
 919 #if 0
 920 /* Experimental code not being used yet. Might speed up file deletion */
 921 /* DeleteWorker scans backwards through the tnode tree and deletes all the
 922  * chunks and tnodes in the file.
 923  * Returns 1 if the tree was deleted.
 924  * Returns 0 if it stopped early due to hitting the limit and the delete is incomplete.
 925  */
 926
 927 static int yaffs_del_worker(yaffs_obj_t *in, yaffs_tnode_t *tn, __u32 level,
 928                               int chunk_offset, int *limit)
 929 {
 930         int i;
 931         int inode_chunk;
 932         int theChunk;
 933         yaffs_ext_tags tags;
 934         int foundChunk;
 935         yaffs_dev_t *dev = in->my_dev;
 936
 937         int allDone = 1;
 938
 939         if (tn) {
 940                 if (level > 0) {
 941                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
 942                              i--) {
 943                                 if (tn->internal[i]) {
 944                                         if (limit && (*limit) < 0) {
 945                                                 allDone = 0;
 946                                         } else {
 947                                                 allDone =
 948                                                         yaffs_del_worker(in,
 949                                                                 tn->
 950                                                                 internal
 951                                                                 [i],
 952                                                                 level -
 953                                                                 1,
 954                                                                 (chunk_offset
 955                                                                         <<
 956                                                                         YAFFS_TNODES_INTERNAL_BITS)
 957                                                                 + i,
 958                                                                 limit);
 959                                         }
 960                                         if (allDone) {
 961                                                 yaffs_free_tnode(dev,
 962                                                                 tn->
 963                                                                 internal[i]);
 964                                                 tn->internal[i] = NULL;
 965                                         }
 966                                 }
 967                         }
 968                         return (allDone) ? 1 : 0;
 969                 } else if (level == 0) {
 970                         int hitLimit = 0;
 971
 972                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0 && !hitLimit;
 973                                         i--) {
 974                                 theChunk = yaffs_get_group_base(dev, tn, i);
 975                                 if (theChunk) {
 976
 977                                         inode_chunk = (chunk_offset <<
 978                                                 YAFFS_TNODES_LEVEL0_BITS) + i;
 979
 980                                         foundChunk =
 981                                                 yaffs_find_chunk_in_group(dev,
 982                                                                 theChunk,
 983                                                                 &tags,
 984                                                                 in->obj_id,
 985                                                                 inode_chunk);
 986
 987                                         if (foundChunk > 0) {
 988                                                 yaffs_chunk_del(dev,
 989                                                                   foundChunk, 1,
 990                                                                   __LINE__);
 991                                                 in->n_data_chunks--;
 992                                                 if (limit) {
 993                                                         *limit = *limit - 1;
 994                                                         if (*limit <= 0)
 995                                                                 hitLimit = 1;
 996                                                 }
 997
 998                                         }
 999
1000                                         yaffs_load_tnode_0(dev, tn, i, 0);
1001                                 }
1002
1003                         }
1004                         return (i < 0) ? 1 : 0;
1005
1006                 }
1007
1008         }
1009
1010         return 1;
1011
1012 }
1013
1014 #endif
1015
1016 static void yaffs_soft_del_chunk(yaffs_dev_t *dev, int chunk)
1017 {
1018         yaffs_block_info_t *theBlock;
1019         unsigned block_no;
1020
1021         T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
1022
1023         block_no =  chunk / dev->param.chunks_per_block;
1024         theBlock = yaffs_get_block_info(dev, block_no);
1025         if (theBlock) {
1026                 theBlock->soft_del_pages++;
1027                 dev->n_free_chunks++;
1028                 yaffs2_update_oldest_dirty_seq(dev, block_no, theBlock);
1029         }
1030 }
1031
1032 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all the chunks in the file.
1033  * All soft deleting does is increment the block's softdelete count and pulls the chunk out
1034  * of the tnode.
1035  * Thus, essentially this is the same as DeleteWorker except that the chunks are soft deleted.
1036  */
1037
1038 static int yaffs_soft_del_worker(yaffs_obj_t *in, yaffs_tnode_t *tn,
1039                                   __u32 level, int chunk_offset)
1040 {
1041         int i;
1042         int theChunk;
1043         int allDone = 1;
1044         yaffs_dev_t *dev = in->my_dev;
1045
1046         if (tn) {
1047                 if (level > 0) {
1048
1049                         for (i = YAFFS_NTNODES_INTERNAL - 1; allDone && i >= 0;
1050                              i--) {
1051                                 if (tn->internal[i]) {
1052                                         allDone =
1053                                             yaffs_soft_del_worker(in,
1054                                                                    tn->
1055                                                                    internal[i],
1056                                                                    level - 1,
1057                                                                    (chunk_offset
1058                                                                     <<
1059                                                                     YAFFS_TNODES_INTERNAL_BITS)
1060                                                                    + i);
1061                                         if (allDone) {
1062                                                 yaffs_free_tnode(dev,
1063                                                                 tn->
1064                                                                 internal[i]);
1065                                                 tn->internal[i] = NULL;
1066                                         } else {
1067                                                 /* Hoosterman... how could this happen? */
1068                                         }
1069                                 }
1070                         }
1071                         return (allDone) ? 1 : 0;
1072                 } else if (level == 0) {
1073
1074                         for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1075                                 theChunk = yaffs_get_group_base(dev, tn, i);
1076                                 if (theChunk) {
1077                                         /* Note this does not find the real chunk, only the chunk group.
1078                                          * We make an assumption that a chunk group is not larger than
1079                                          * a block.
1080                                          */
1081                                         yaffs_soft_del_chunk(dev, theChunk);
1082                                         yaffs_load_tnode_0(dev, tn, i, 0);
1083                                 }
1084
1085                         }
1086                         return 1;
1087
1088                 }
1089
1090         }
1091
1092         return 1;
1093
1094 }
1095
1096 static void yaffs_soft_del_file(yaffs_obj_t *obj)
1097 {
1098         if (obj->deleted &&
1099             obj->variant_type == YAFFS_OBJECT_TYPE_FILE && !obj->soft_del) {
1100                 if (obj->n_data_chunks <= 0) {
1101                         /* Empty file with no duplicate object headers, just delete it immediately */
1102                         yaffs_free_tnode(obj->my_dev,
1103                                         obj->variant.file_variant.top);
1104                         obj->variant.file_variant.top = NULL;
1105                         T(YAFFS_TRACE_TRACING,
1106                           (TSTR("yaffs: Deleting empty file %d" TENDSTR),
1107                            obj->obj_id));
1108                         yaffs_generic_obj_del(obj);
1109                 } else {
1110                         yaffs_soft_del_worker(obj,
1111                                                obj->variant.file_variant.top,
1112                                                obj->variant.file_variant.
1113                                                top_level, 0);
1114                         obj->soft_del = 1;
1115                 }
1116         }
1117 }
1118
1119 /* Pruning removes any part of the file structure tree that is beyond the
1120  * bounds of the file (ie that does not point to chunks).
1121  *
1122  * A file should only get pruned when its size is reduced.
1123  *
1124  * Before pruning, the chunks must be pulled from the tree and the
1125  * level 0 tnode entries must be zeroed out.
1126  * Could also use this for file deletion, but that's probably better handled
1127  * by a special case.
1128  *
1129  * This function is recursive. For levels > 0 the function is called again on
1130  * any sub-tree. For level == 0 we just check if the sub-tree has data.
1131  * If there is no data in a subtree then it is pruned.
1132  */
1133
1134 static yaffs_tnode_t *yaffs_prune_worker(yaffs_dev_t *dev, yaffs_tnode_t *tn,
1135                                 __u32 level, int del0)
1136 {
1137         int i;
1138         int hasData;
1139
1140         if (tn) {
1141                 hasData = 0;
1142
1143                 if(level > 0){
1144                         for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1145                                 if (tn->internal[i]) {
1146                                         tn->internal[i] =
1147                                                 yaffs_prune_worker(dev, tn->internal[i],
1148                                                         level - 1,
1149                                                         (i == 0) ? del0 : 1);
1150                                 }
1151
1152                                 if (tn->internal[i])
1153                                         hasData++;
1154                         }
1155                 } else {
1156                         int tnode_size_u32 = dev->tnode_size/sizeof(__u32);
1157                         __u32 *map = (__u32 *)tn;
1158
1159                         for(i = 0; !hasData && i < tnode_size_u32; i++){
1160                                 if(map[i])
1161                                         hasData++;
1162                         }
1163                 }
1164
1165                 if (hasData == 0 && del0) {
1166                         /* Free and return NULL */
1167
1168                         yaffs_free_tnode(dev, tn);
1169                         tn = NULL;
1170                 }
1171
1172         }
1173
1174         return tn;
1175
1176 }
1177
1178 static int yaffs_prune_tree(yaffs_dev_t *dev,
1179                                 yaffs_file_s *file_struct)
1180 {
1181         int i;
1182         int hasData;
1183         int done = 0;
1184         yaffs_tnode_t *tn;
1185
1186         if (file_struct->top_level > 0) {
1187                 file_struct->top =
1188                     yaffs_prune_worker(dev, file_struct->top, file_struct->top_level, 0);
1189
1190                 /* Now we have a tree with all the non-zero branches NULL but the height
1191                  * is the same as it was.
1192                  * Let's see if we can trim internal tnodes to shorten the tree.
1193                  * We can do this if only the 0th element in the tnode is in use
1194                  * (ie all the non-zero are NULL)
1195                  */
1196
1197                 while (file_struct->top_level && !done) {
1198                         tn = file_struct->top;
1199
1200                         hasData = 0;
1201                         for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1202                                 if (tn->internal[i])
1203                                         hasData++;
1204                         }
1205
1206                         if (!hasData) {
1207                                 file_struct->top = tn->internal[0];
1208                                 file_struct->top_level--;
1209                                 yaffs_free_tnode(dev, tn);
1210                         } else {
1211                                 done = 1;
1212                         }
1213                 }
1214         }
1215
1216         return YAFFS_OK;
1217 }
1218
1219 /*-------------------- End of File Structure functions.-------------------*/
1220
1221
1222 /* AllocateEmptyObject gets us a clean Object. Tries to make allocate more if we run out */
1223 static yaffs_obj_t *yaffs_alloc_empty_obj(yaffs_dev_t *dev)
1224 {
1225         yaffs_obj_t *obj = yaffs_alloc_raw_obj(dev);
1226
1227         if (obj) {
1228                 dev->n_obj++;
1229
1230                 /* Now sweeten it up... */
1231
1232                 memset(obj, 0, sizeof(yaffs_obj_t));
1233                 obj->being_created = 1;
1234
1235                 obj->my_dev = dev;
1236                 obj->hdr_chunk = 0;
1237                 obj->variant_type = YAFFS_OBJECT_TYPE_UNKNOWN;
1238                 YINIT_LIST_HEAD(&(obj->hard_links));
1239                 YINIT_LIST_HEAD(&(obj->hash_link));
1240                 YINIT_LIST_HEAD(&obj->siblings);
1241
1242
1243                 /* Now make the directory sane */
1244                 if (dev->root_dir) {
1245                         obj->parent = dev->root_dir;
1246                         ylist_add(&(obj->siblings), &dev->root_dir->variant.dir_variant.children);
1247                 }
1248
1249                 /* Add it to the lost and found directory.
1250                  * NB Can't put root or lostNFound in lostNFound so
1251                  * check if lostNFound exists first
1252                  */
1253                 if (dev->lost_n_found)
1254                         yaffs_add_obj_to_dir(dev->lost_n_found, obj);
1255
1256                 obj->being_created = 0;
1257         }
1258
1259         dev->checkpoint_blocks_required = 0; /* force recalculation*/
1260
1261         return obj;
1262 }
1263
1264 static yaffs_obj_t *yaffs_create_fake_dir(yaffs_dev_t *dev, int number,
1265                                                __u32 mode)
1266 {
1267
1268         yaffs_obj_t *obj =
1269             yaffs_new_obj(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
1270         if (obj) {
1271                 obj->fake = 1;          /* it is fake so it might have no NAND presence... */
1272                 obj->rename_allowed = 0;        /* ... and we're not allowed to rename it... */
1273                 obj->unlink_allowed = 0;        /* ... or unlink it */
1274                 obj->deleted = 0;
1275                 obj->unlinked = 0;
1276                 obj->yst_mode = mode;
1277                 obj->my_dev = dev;
1278                 obj->hdr_chunk = 0;     /* Not a valid chunk. */
1279         }
1280
1281         return obj;
1282
1283 }
1284
1285 static void yaffs_unhash_obj(yaffs_obj_t *obj)
1286 {
1287         int bucket;
1288         yaffs_dev_t *dev = obj->my_dev;
1289
1290         /* If it is still linked into the bucket list, free from the list */
1291         if (!ylist_empty(&obj->hash_link)) {
1292                 ylist_del_init(&obj->hash_link);
1293                 bucket = yaffs_hash_fn(obj->obj_id);
1294                 dev->obj_bucket[bucket].count--;
1295         }
1296 }
1297
1298 /*  FreeObject frees up a Object and puts it back on the free list */
1299 static void yaffs_free_obj(yaffs_obj_t *obj)
1300 {
1301         yaffs_dev_t *dev = obj->my_dev;
1302
1303         T(YAFFS_TRACE_OS, (TSTR("FreeObject %p inode %p"TENDSTR), obj, obj->my_inode));
1304
1305         if (!obj)
1306                 YBUG();
1307         if (obj->parent)
1308                 YBUG();
1309         if (!ylist_empty(&obj->siblings))
1310                 YBUG();
1311
1312
1313         if (obj->my_inode) {
1314                 /* We're still hooked up to a cached inode.
1315                  * Don't delete now, but mark for later deletion
1316                  */
1317                 obj->defered_free = 1;
1318                 return;
1319         }
1320
1321         yaffs_unhash_obj(obj);
1322
1323         yaffs_free_raw_obj(dev,obj);
1324         dev->n_obj--;
1325         dev->checkpoint_blocks_required = 0; /* force recalculation*/
1326 }
1327
1328
1329 void yaffs_handle_defered_free(yaffs_obj_t *obj)
1330 {
1331         if (obj->defered_free)
1332                 yaffs_free_obj(obj);
1333 }
1334
1335 static void yaffs_init_tnodes_and_objs(yaffs_dev_t *dev)
1336 {
1337         int i;
1338
1339         dev->n_obj = 0;
1340         dev->n_tnodes = 0;
1341
1342         yaffs_init_raw_tnodes_and_objs(dev);
1343
1344         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
1345                 YINIT_LIST_HEAD(&dev->obj_bucket[i].list);
1346                 dev->obj_bucket[i].count = 0;
1347         }
1348 }
1349
1350 static int yaffs_find_nice_bucket(yaffs_dev_t *dev)
1351 {
1352         int i;
1353         int l = 999;
1354         int lowest = 999999;
1355
1356
1357         /* Search for the shortest list or one that
1358          * isn't too long.
1359          */
1360
1361         for (i = 0; i < 10 && lowest > 4; i++) {
1362                 dev->bucket_finder++;
1363                 dev->bucket_finder %= YAFFS_NOBJECT_BUCKETS;
1364                 if (dev->obj_bucket[dev->bucket_finder].count < lowest) {
1365                         lowest = dev->obj_bucket[dev->bucket_finder].count;
1366                         l = dev->bucket_finder;
1367                 }
1368
1369         }
1370
1371         return l;
1372 }
1373
1374 static int yaffs_new_obj_id(yaffs_dev_t *dev)
1375 {
1376         int bucket = yaffs_find_nice_bucket(dev);
1377
1378         /* Now find an object value that has not already been taken
1379          * by scanning the list.
1380          */
1381
1382         int found = 0;
1383         struct ylist_head *i;
1384
1385         __u32 n = (__u32) bucket;
1386
1387         /* yaffs_check_obj_hash_sane();  */
1388
1389         while (!found) {
1390                 found = 1;
1391                 n += YAFFS_NOBJECT_BUCKETS;
1392                 if (1 || dev->obj_bucket[bucket].count > 0) {
1393                         ylist_for_each(i, &dev->obj_bucket[bucket].list) {
1394                                 /* If there is already one in the list */
1395                                 if (i && ylist_entry(i, yaffs_obj_t,
1396                                                 hash_link)->obj_id == n) {
1397                                         found = 0;
1398                                 }
1399                         }
1400                 }
1401         }
1402
1403         return n;
1404 }
1405
1406 static void yaffs_hash_obj(yaffs_obj_t *in)
1407 {
1408         int bucket = yaffs_hash_fn(in->obj_id);
1409         yaffs_dev_t *dev = in->my_dev;
1410
1411         ylist_add(&in->hash_link, &dev->obj_bucket[bucket].list);
1412         dev->obj_bucket[bucket].count++;
1413 }
1414
1415 yaffs_obj_t *yaffs_find_by_number(yaffs_dev_t *dev, __u32 number)
1416 {
1417         int bucket = yaffs_hash_fn(number);
1418         struct ylist_head *i;
1419         yaffs_obj_t *in;
1420
1421         ylist_for_each(i, &dev->obj_bucket[bucket].list) {
1422                 /* Look if it is in the list */
1423                 if (i) {
1424                         in = ylist_entry(i, yaffs_obj_t, hash_link);
1425                         if (in->obj_id == number) {
1426
1427                                 /* Don't tell the VFS about this one if it is defered free */
1428                                 if (in->defered_free)
1429                                         return NULL;
1430
1431                                 return in;
1432                         }
1433                 }
1434         }
1435
1436         return NULL;
1437 }
1438
1439 yaffs_obj_t *yaffs_new_obj(yaffs_dev_t *dev, int number,
1440                                     yaffs_obj_type type)
1441 {
1442         yaffs_obj_t *theObject=NULL;
1443         yaffs_tnode_t *tn = NULL;
1444
1445         if (number < 0)
1446                 number = yaffs_new_obj_id(dev);
1447
1448         if (type == YAFFS_OBJECT_TYPE_FILE) {
1449                 tn = yaffs_get_tnode(dev);
1450                 if (!tn)
1451                         return NULL;
1452         }
1453
1454         theObject = yaffs_alloc_empty_obj(dev);
1455         if (!theObject){
1456                 if(tn)
1457                         yaffs_free_tnode(dev,tn);
1458                 return NULL;
1459         }
1460
1461
1462         if (theObject) {
1463                 theObject->fake = 0;
1464                 theObject->rename_allowed = 1;
1465                 theObject->unlink_allowed = 1;
1466                 theObject->obj_id = number;
1467                 yaffs_hash_obj(theObject);
1468                 theObject->variant_type = type;
1469 #ifdef CONFIG_YAFFS_WINCE
1470                 yfsd_win_file_time_now(theObject->win_atime);
1471                 theObject->win_ctime[0] = theObject->win_mtime[0] =
1472                     theObject->win_atime[0];
1473                 theObject->win_ctime[1] = theObject->win_mtime[1] =
1474                     theObject->win_atime[1];
1475
1476 #else
1477
1478                 theObject->yst_atime = theObject->yst_mtime =
1479                     theObject->yst_ctime = Y_CURRENT_TIME;
1480 #endif
1481                 switch (type) {
1482                 case YAFFS_OBJECT_TYPE_FILE:
1483                         theObject->variant.file_variant.file_size = 0;
1484                         theObject->variant.file_variant.scanned_size = 0;
1485                         theObject->variant.file_variant.shrink_size = 0xFFFFFFFF;       /* max __u32 */
1486                         theObject->variant.file_variant.top_level = 0;
1487                         theObject->variant.file_variant.top = tn;
1488                         break;
1489                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1490                         YINIT_LIST_HEAD(&theObject->variant.dir_variant.
1491                                         children);
1492                         YINIT_LIST_HEAD(&theObject->variant.dir_variant.
1493                                         dirty);
1494                         break;
1495                 case YAFFS_OBJECT_TYPE_SYMLINK:
1496                 case YAFFS_OBJECT_TYPE_HARDLINK:
1497                 case YAFFS_OBJECT_TYPE_SPECIAL:
1498                         /* No action required */
1499                         break;
1500                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1501                         /* todo this should not happen */
1502                         break;
1503                 }
1504         }
1505
1506         return theObject;
1507 }
1508
1509 yaffs_obj_t *yaffs_find_or_create_by_number(yaffs_dev_t *dev,
1510                                                 int number,
1511                                                 yaffs_obj_type type)
1512 {
1513         yaffs_obj_t *theObject = NULL;
1514
1515         if (number > 0)
1516                 theObject = yaffs_find_by_number(dev, number);
1517
1518         if (!theObject)
1519                 theObject = yaffs_new_obj(dev, number, type);
1520
1521         return theObject;
1522
1523 }
1524
1525
1526 YCHAR *yaffs_clone_str(const YCHAR *str)
1527 {
1528         YCHAR *newStr = NULL;
1529         int len;
1530
1531         if (!str)
1532                 str = _Y("");
1533
1534         len = yaffs_strnlen(str,YAFFS_MAX_ALIAS_LENGTH);
1535         newStr = YMALLOC((len + 1) * sizeof(YCHAR));
1536         if (newStr){
1537                 yaffs_strncpy(newStr, str,len);
1538                 newStr[len] = 0;
1539         }
1540         return newStr;
1541
1542 }
1543
1544 /*
1545  * Mknod (create) a new object.
1546  * equiv_obj only has meaning for a hard link;
1547  * aliasString only has meaning for a symlink.
1548  * rdev only has meaning for devices (a subset of special objects)
1549  */
1550
1551 static yaffs_obj_t *yaffs_create_obj(yaffs_obj_type type,
1552                                        yaffs_obj_t *parent,
1553                                        const YCHAR *name,
1554                                        __u32 mode,
1555                                        __u32 uid,
1556                                        __u32 gid,
1557                                        yaffs_obj_t *equiv_obj,
1558                                        const YCHAR *aliasString, __u32 rdev)
1559 {
1560         yaffs_obj_t *in;
1561         YCHAR *str = NULL;
1562
1563         yaffs_dev_t *dev = parent->my_dev;
1564
1565         /* Check if the entry exists. If it does then fail the call since we don't want a dup.*/
1566         if (yaffs_find_by_name(parent, name))
1567                 return NULL;
1568
1569         if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
1570                 str = yaffs_clone_str(aliasString);
1571                 if (!str)
1572                         return NULL;
1573         }
1574
1575         in = yaffs_new_obj(dev, -1, type);
1576
1577         if (!in){
1578                 if(str)
1579                         YFREE(str);
1580                 return NULL;
1581         }
1582
1583
1584
1585
1586
1587         if (in) {
1588                 in->hdr_chunk = 0;
1589                 in->valid = 1;
1590                 in->variant_type = type;
1591
1592                 in->yst_mode = mode;
1593
1594 #ifdef CONFIG_YAFFS_WINCE
1595                 yfsd_win_file_time_now(in->win_atime);
1596                 in->win_ctime[0] = in->win_mtime[0] = in->win_atime[0];
1597                 in->win_ctime[1] = in->win_mtime[1] = in->win_atime[1];
1598
1599 #else
1600                 in->yst_atime = in->yst_mtime = in->yst_ctime = Y_CURRENT_TIME;
1601
1602                 in->yst_rdev = rdev;
1603                 in->yst_uid = uid;
1604                 in->yst_gid = gid;
1605 #endif
1606                 in->n_data_chunks = 0;
1607
1608                 yaffs_set_obj_name(in, name);
1609                 in->dirty = 1;
1610
1611                 yaffs_add_obj_to_dir(parent, in);
1612
1613                 in->my_dev = parent->my_dev;
1614
1615                 switch (type) {
1616                 case YAFFS_OBJECT_TYPE_SYMLINK:
1617                         in->variant.symlink_variant.alias = str;
1618                         break;
1619                 case YAFFS_OBJECT_TYPE_HARDLINK:
1620                         in->variant.hardlink_variant.equiv_obj =
1621                                 equiv_obj;
1622                         in->variant.hardlink_variant.equiv_id =
1623                                 equiv_obj->obj_id;
1624                         ylist_add(&in->hard_links, &equiv_obj->hard_links);
1625                         break;
1626                 case YAFFS_OBJECT_TYPE_FILE:
1627                 case YAFFS_OBJECT_TYPE_DIRECTORY:
1628                 case YAFFS_OBJECT_TYPE_SPECIAL:
1629                 case YAFFS_OBJECT_TYPE_UNKNOWN:
1630                         /* do nothing */
1631                         break;
1632                 }
1633
1634                 if (yaffs_update_oh(in, name, 0, 0, 0, NULL) < 0) {
1635                         /* Could not create the object header, fail the creation */
1636                         yaffs_del_obj(in);
1637                         in = NULL;
1638                 }
1639
1640                 yaffs_update_parent(parent);
1641         }
1642
1643         return in;
1644 }
1645
1646 yaffs_obj_t *yaffs_create_file(yaffs_obj_t *parent, const YCHAR *name,
1647                         __u32 mode, __u32 uid, __u32 gid)
1648 {
1649         return yaffs_create_obj(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
1650                                 uid, gid, NULL, NULL, 0);
1651 }
1652
1653 yaffs_obj_t *yaffs_create_dir(yaffs_obj_t *parent, const YCHAR *name,
1654                                 __u32 mode, __u32 uid, __u32 gid)
1655 {
1656         return yaffs_create_obj(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
1657                                  mode, uid, gid, NULL, NULL, 0);
1658 }
1659
1660 yaffs_obj_t *yaffs_create_special(yaffs_obj_t *parent, const YCHAR *name,
1661                                 __u32 mode, __u32 uid, __u32 gid, __u32 rdev)
1662 {
1663         return yaffs_create_obj(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
1664                                  uid, gid, NULL, NULL, rdev);
1665 }
1666
1667 yaffs_obj_t *yaffs_create_symlink(yaffs_obj_t *parent, const YCHAR *name,
1668                                 __u32 mode, __u32 uid, __u32 gid,
1669                                 const YCHAR *alias)
1670 {
1671         return yaffs_create_obj(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
1672                                 uid, gid, NULL, alias, 0);
1673 }
1674
1675 /* yaffs_link_obj returns the object id of the equivalent object.*/
1676 yaffs_obj_t *yaffs_link_obj(yaffs_obj_t *parent, const YCHAR *name,
1677                         yaffs_obj_t *equiv_obj)
1678 {
1679         /* Get the real object in case we were fed a hard link as an equivalent object */
1680         equiv_obj = yaffs_get_equivalent_obj(equiv_obj);
1681
1682         if (yaffs_create_obj
1683             (YAFFS_OBJECT_TYPE_HARDLINK, parent, name, 0, 0, 0,
1684              equiv_obj, NULL, 0)) {
1685                 return equiv_obj;
1686         } else {
1687                 return NULL;
1688         }
1689
1690 }
1691
1692 static int yaffs_change_obj_name(yaffs_obj_t *obj, yaffs_obj_t *new_dir,
1693                                 const YCHAR *new_name, int force, int shadows)
1694 {
1695         int unlinkOp;
1696         int deleteOp;
1697
1698         yaffs_obj_t *existingTarget;
1699
1700         if (new_dir == NULL)
1701                 new_dir = obj->parent;  /* use the old directory */
1702
1703         if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
1704                 T(YAFFS_TRACE_ALWAYS,
1705                   (TSTR
1706                    ("tragedy: yaffs_change_obj_name: new_dir is not a directory"
1707                     TENDSTR)));
1708                 YBUG();
1709         }
1710
1711         /* TODO: Do we need this different handling for YAFFS2 and YAFFS1?? */
1712         if (obj->my_dev->param.is_yaffs2)
1713                 unlinkOp = (new_dir == obj->my_dev->unlinked_dir);
1714         else
1715                 unlinkOp = (new_dir == obj->my_dev->unlinked_dir
1716                             && obj->variant_type == YAFFS_OBJECT_TYPE_FILE);
1717
1718         deleteOp = (new_dir == obj->my_dev->del_dir);
1719
1720         existingTarget = yaffs_find_by_name(new_dir, new_name);
1721
1722         /* If the object is a file going into the unlinked directory,
1723          *   then it is OK to just stuff it in since duplicate names are allowed.
1724          *   else only proceed if the new name does not exist and if we're putting
1725          *   it into a directory.
1726          */
1727         if ((unlinkOp ||
1728              deleteOp ||
1729              force ||
1730              (shadows > 0) ||
1731              !existingTarget) &&
1732             new_dir->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) {
1733                 yaffs_set_obj_name(obj, new_name);
1734                 obj->dirty = 1;
1735
1736                 yaffs_add_obj_to_dir(new_dir, obj);
1737
1738                 if (unlinkOp)
1739                         obj->unlinked = 1;
1740
1741                 /* If it is a deletion then we mark it as a shrink for gc purposes. */
1742                 if (yaffs_update_oh(obj, new_name, 0, deleteOp, shadows, NULL) >= 0)
1743                         return YAFFS_OK;
1744         }
1745
1746         return YAFFS_FAIL;
1747 }
1748
1749 int yaffs_rename_obj(yaffs_obj_t *old_dir, const YCHAR *old_name,
1750                 yaffs_obj_t *new_dir, const YCHAR *new_name)
1751 {
1752         yaffs_obj_t *obj = NULL;
1753         yaffs_obj_t *existingTarget = NULL;
1754         int force = 0;
1755         int result;
1756         yaffs_dev_t *dev;
1757
1758
1759         if (!old_dir || old_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
1760                 YBUG();
1761         if (!new_dir || new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
1762                 YBUG();
1763
1764         dev = old_dir->my_dev;
1765
1766 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
1767         /* Special case for case insemsitive systems (eg. WinCE).
1768          * While look-up is case insensitive, the name isn't.
1769          * Therefore we might want to change x.txt to X.txt
1770         */
1771         if (old_dir == new_dir && yaffs_strcmp(old_name, new_name) == 0)
1772                 force = 1;
1773 #endif
1774
1775         if(yaffs_strnlen(new_name,YAFFS_MAX_NAME_LENGTH+1) > YAFFS_MAX_NAME_LENGTH)
1776                 /* ENAMETOOLONG */
1777                 return YAFFS_FAIL;
1778
1779         obj = yaffs_find_by_name(old_dir, old_name);
1780
1781         if (obj && obj->rename_allowed) {
1782
1783                 /* Now do the handling for an existing target, if there is one */
1784
1785                 existingTarget = yaffs_find_by_name(new_dir, new_name);
1786                 if (existingTarget &&
1787                         existingTarget->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY &&
1788                         !ylist_empty(&existingTarget->variant.dir_variant.children)) {
1789                         /* There is a target that is a non-empty directory, so we fail */
1790                         return YAFFS_FAIL;      /* EEXIST or ENOTEMPTY */
1791                 } else if (existingTarget && existingTarget != obj) {
1792                         /* Nuke the target first, using shadowing,
1793                          * but only if it isn't the same object.
1794                          *
1795                          * Note we must disable gc otherwise it can mess up the shadowing.
1796                          *
1797                          */
1798                         dev->gc_disable=1;
1799                         yaffs_change_obj_name(obj, new_dir, new_name, force,
1800                                                 existingTarget->obj_id);
1801                         existingTarget->is_shadowed = 1;
1802                         yaffs_unlink_obj(existingTarget);
1803                         dev->gc_disable=0;
1804                 }
1805
1806                 result = yaffs_change_obj_name(obj, new_dir, new_name, 1, 0);
1807
1808                 yaffs_update_parent(old_dir);
1809                 if(new_dir != old_dir)
1810                         yaffs_update_parent(new_dir);
1811
1812                 return result;
1813         }
1814         return YAFFS_FAIL;
1815 }
1816
1817 /*------------------------- Block Management and Page Allocation ----------------*/
1818
1819 static int yaffs_init_blocks(yaffs_dev_t *dev)
1820 {
1821         int nBlocks = dev->internal_end_block - dev->internal_start_block + 1;
1822
1823         dev->block_info = NULL;
1824         dev->chunk_bits = NULL;
1825
1826         dev->alloc_block = -1;  /* force it to get a new one */
1827
1828         /* If the first allocation strategy fails, thry the alternate one */
1829         dev->block_info = YMALLOC(nBlocks * sizeof(yaffs_block_info_t));
1830         if (!dev->block_info) {
1831                 dev->block_info = YMALLOC_ALT(nBlocks * sizeof(yaffs_block_info_t));
1832                 dev->block_info_alt = 1;
1833         } else
1834                 dev->block_info_alt = 0;
1835
1836         if (dev->block_info) {
1837                 /* Set up dynamic blockinfo stuff. */
1838                 dev->chunk_bit_stride = (dev->param.chunks_per_block + 7) / 8; /* round up bytes */
1839                 dev->chunk_bits = YMALLOC(dev->chunk_bit_stride * nBlocks);
1840                 if (!dev->chunk_bits) {
1841                         dev->chunk_bits = YMALLOC_ALT(dev->chunk_bit_stride * nBlocks);
1842                         dev->chunk_bits_alt = 1;
1843                 } else
1844                         dev->chunk_bits_alt = 0;
1845         }
1846
1847         if (dev->block_info && dev->chunk_bits) {
1848                 memset(dev->block_info, 0, nBlocks * sizeof(yaffs_block_info_t));
1849                 memset(dev->chunk_bits, 0, dev->chunk_bit_stride * nBlocks);
1850                 return YAFFS_OK;
1851         }
1852
1853         return YAFFS_FAIL;
1854 }
1855
1856 static void yaffs_deinit_blocks(yaffs_dev_t *dev)
1857 {
1858         if (dev->block_info_alt && dev->block_info)
1859                 YFREE_ALT(dev->block_info);
1860         else if (dev->block_info)
1861                 YFREE(dev->block_info);
1862
1863         dev->block_info_alt = 0;
1864
1865         dev->block_info = NULL;
1866
1867         if (dev->chunk_bits_alt && dev->chunk_bits)
1868                 YFREE_ALT(dev->chunk_bits);
1869         else if (dev->chunk_bits)
1870                 YFREE(dev->chunk_bits);
1871         dev->chunk_bits_alt = 0;
1872         dev->chunk_bits = NULL;
1873 }
1874
1875 void yaffs_block_became_dirty(yaffs_dev_t *dev, int block_no)
1876 {
1877         yaffs_block_info_t *bi = yaffs_get_block_info(dev, block_no);
1878
1879         int erasedOk = 0;
1880
1881         /* If the block is still healthy erase it and mark as clean.
1882          * If the block has had a data failure, then retire it.
1883          */
1884
1885         T(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
1886                 (TSTR("yaffs_block_became_dirty block %d state %d %s"TENDSTR),
1887                 block_no, bi->block_state, (bi->needs_retiring) ? "needs retiring" : ""));
1888
1889         yaffs2_clear_oldest_dirty_seq(dev,bi);
1890
1891         bi->block_state = YAFFS_BLOCK_STATE_DIRTY;
1892
1893         /* If this is the block being garbage collected then stop gc'ing this block */
1894         if(block_no == dev->gc_block)
1895                 dev->gc_block = 0;
1896
1897         /* If this block is currently the best candidate for gc then drop as a candidate */
1898         if(block_no == dev->gc_dirtiest){
1899                 dev->gc_dirtiest = 0;
1900                 dev->gc_pages_in_use = 0;
1901         }
1902
1903         if (!bi->needs_retiring) {
1904                 yaffs2_checkpt_invalidate(dev);
1905                 erasedOk = yaffs_erase_block(dev, block_no);
1906                 if (!erasedOk) {
1907                         dev->n_erase_failures++;
1908                         T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
1909                           (TSTR("**>> Erasure failed %d" TENDSTR), block_no));
1910                 }
1911         }
1912
1913         if (erasedOk &&
1914             ((yaffs_trace_mask & YAFFS_TRACE_ERASE) || !yaffs_skip_verification(dev))) {
1915                 int i;
1916                 for (i = 0; i < dev->param.chunks_per_block; i++) {
1917                         if (!yaffs_check_chunk_erased
1918                             (dev, block_no * dev->param.chunks_per_block + i)) {
1919                                 T(YAFFS_TRACE_ERROR,
1920                                   (TSTR
1921                                    (">>Block %d erasure supposedly OK, but chunk %d not erased"
1922                                     TENDSTR), block_no, i));
1923                         }
1924                 }
1925         }
1926
1927         if (erasedOk) {
1928                 /* Clean it up... */
1929                 bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
1930                 bi->seq_number = 0;
1931                 dev->n_erased_blocks++;
1932                 bi->pages_in_use = 0;
1933                 bi->soft_del_pages = 0;
1934                 bi->has_shrink_hdr = 0;
1935                 bi->skip_erased_check = 1;  /* This is clean, so no need to check */
1936                 bi->gc_prioritise = 0;
1937                 yaffs_clear_chunk_bits(dev, block_no);
1938
1939                 T(YAFFS_TRACE_ERASE,
1940                   (TSTR("Erased block %d" TENDSTR), block_no));
1941         } else {
1942                 dev->n_free_chunks -= dev->param.chunks_per_block;      /* We lost a block of free space */
1943
1944                 yaffs_retire_block(dev, block_no);
1945                 T(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
1946                   (TSTR("**>> Block %d retired" TENDSTR), block_no));
1947         }
1948 }
1949
1950 static int yaffs_find_alloc_block(yaffs_dev_t *dev)
1951 {
1952         int i;
1953
1954         yaffs_block_info_t *bi;
1955
1956         if (dev->n_erased_blocks < 1) {
1957                 /* Hoosterman we've got a problem.
1958                  * Can't get space to gc
1959                  */
1960                 T(YAFFS_TRACE_ERROR,
1961                   (TSTR("yaffs tragedy: no more erased blocks" TENDSTR)));
1962
1963                 return -1;
1964         }
1965
1966         /* Find an empty block. */
1967
1968         for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
1969                 dev->alloc_block_finder++;
1970                 if (dev->alloc_block_finder < dev->internal_start_block
1971                     || dev->alloc_block_finder > dev->internal_end_block) {
1972                         dev->alloc_block_finder = dev->internal_start_block;
1973                 }
1974
1975                 bi = yaffs_get_block_info(dev, dev->alloc_block_finder);
1976
1977                 if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
1978                         bi->block_state = YAFFS_BLOCK_STATE_ALLOCATING;
1979                         dev->seq_number++;
1980                         bi->seq_number = dev->seq_number;
1981                         dev->n_erased_blocks--;
1982                         T(YAFFS_TRACE_ALLOCATE,
1983                           (TSTR("Allocated block %d, seq  %d, %d left" TENDSTR),
1984                            dev->alloc_block_finder, dev->seq_number,
1985                            dev->n_erased_blocks));
1986                         return dev->alloc_block_finder;
1987                 }
1988         }
1989
1990         T(YAFFS_TRACE_ALWAYS,
1991           (TSTR
1992            ("yaffs tragedy: no more erased blocks, but there should have been %d"
1993             TENDSTR), dev->n_erased_blocks));
1994
1995         return -1;
1996 }
1997
1998
1999 /*
2000  * Check if there's space to allocate...
2001  * Thinks.... do we need top make this ths same as yaffs_get_free_chunks()?
2002  */
2003 int yaffs_check_alloc_available(yaffs_dev_t *dev, int n_chunks)
2004 {
2005         int reservedChunks;
2006         int reservedBlocks = dev->param.n_reserved_blocks;
2007         int checkpointBlocks;
2008
2009         checkpointBlocks = yaffs_calc_checkpt_blocks_required(dev);
2010
2011         reservedChunks = ((reservedBlocks + checkpointBlocks) * dev->param.chunks_per_block);
2012
2013         return (dev->n_free_chunks > (reservedChunks + n_chunks));
2014 }
2015
2016 static int yaffs_alloc_chunk(yaffs_dev_t *dev, int useReserve,
2017                 yaffs_block_info_t **blockUsedPtr)
2018 {
2019         int retVal;
2020         yaffs_block_info_t *bi;
2021
2022         if (dev->alloc_block < 0) {
2023                 /* Get next block to allocate off */
2024                 dev->alloc_block = yaffs_find_alloc_block(dev);
2025                 dev->alloc_page = 0;
2026         }
2027
2028         if (!useReserve && !yaffs_check_alloc_available(dev, 1)) {
2029                 /* Not enough space to allocate unless we're allowed to use the reserve. */
2030                 return -1;
2031         }
2032
2033         if (dev->n_erased_blocks < dev->param.n_reserved_blocks
2034                         && dev->alloc_page == 0) {
2035                 T(YAFFS_TRACE_ALLOCATE, (TSTR("Allocating reserve" TENDSTR)));
2036         }
2037
2038         /* Next page please.... */
2039         if (dev->alloc_block >= 0) {
2040                 bi = yaffs_get_block_info(dev, dev->alloc_block);
2041
2042                 retVal = (dev->alloc_block * dev->param.chunks_per_block) +
2043                         dev->alloc_page;
2044                 bi->pages_in_use++;
2045                 yaffs_set_chunk_bit(dev, dev->alloc_block,
2046                                 dev->alloc_page);
2047
2048                 dev->alloc_page++;
2049
2050                 dev->n_free_chunks--;
2051
2052                 /* If the block is full set the state to full */
2053                 if (dev->alloc_page >= dev->param.chunks_per_block) {
2054                         bi->block_state = YAFFS_BLOCK_STATE_FULL;
2055                         dev->alloc_block = -1;
2056                 }
2057
2058                 if (blockUsedPtr)
2059                         *blockUsedPtr = bi;
2060
2061                 return retVal;
2062         }
2063
2064         T(YAFFS_TRACE_ERROR,
2065                         (TSTR("!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!" TENDSTR)));
2066
2067         return -1;
2068 }
2069
2070 static int yaffs_get_erased_chunks(yaffs_dev_t *dev)
2071 {
2072         int n;
2073
2074         n = dev->n_erased_blocks * dev->param.chunks_per_block;
2075
2076         if (dev->alloc_block > 0)
2077                 n += (dev->param.chunks_per_block - dev->alloc_page);
2078
2079         return n;
2080
2081 }
2082
2083 /*
2084  * yaffs_skip_rest_of_block() skips over the rest of the allocation block
2085  * if we don't want to write to it.
2086  */
2087 void yaffs_skip_rest_of_block(yaffs_dev_t *dev)
2088 {
2089         if(dev->alloc_block > 0){
2090                 yaffs_block_info_t *bi = yaffs_get_block_info(dev, dev->alloc_block);
2091                 if(bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING){
2092                         bi->block_state = YAFFS_BLOCK_STATE_FULL;
2093                         dev->alloc_block = -1;
2094                 }
2095         }
2096 }
2097
2098
2099 static int yaffs_gc_block(yaffs_dev_t *dev, int block,
2100                 int wholeBlock)
2101 {
2102         int oldChunk;
2103         int newChunk;
2104         int mark_flash;
2105         int retVal = YAFFS_OK;
2106         int i;
2107         int isCheckpointBlock;
2108         int matchingChunk;
2109         int maxCopies;
2110
2111         int chunksBefore = yaffs_get_erased_chunks(dev);
2112         int chunksAfter;
2113
2114         yaffs_ext_tags tags;
2115
2116         yaffs_block_info_t *bi = yaffs_get_block_info(dev, block);
2117
2118         yaffs_obj_t *object;
2119
2120         isCheckpointBlock = (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT);
2121
2122
2123         T(YAFFS_TRACE_TRACING,
2124                         (TSTR("Collecting block %d, in use %d, shrink %d, wholeBlock %d" TENDSTR),
2125                          block,
2126                          bi->pages_in_use,
2127                          bi->has_shrink_hdr,
2128                          wholeBlock));
2129
2130         /*yaffs_verify_free_chunks(dev); */
2131
2132         if(bi->block_state == YAFFS_BLOCK_STATE_FULL)
2133                 bi->block_state = YAFFS_BLOCK_STATE_COLLECTING;
2134
2135         bi->has_shrink_hdr = 0; /* clear the flag so that the block can erase */
2136
2137         dev->gc_disable = 1;
2138
2139         if (isCheckpointBlock ||
2140                         !yaffs_still_some_chunks(dev, block)) {
2141                 T(YAFFS_TRACE_TRACING,
2142                                 (TSTR
2143                                  ("Collecting block %d that has no chunks in use" TENDSTR),
2144                                  block));
2145                 yaffs_block_became_dirty(dev, block);
2146         } else {
2147
2148                 __u8 *buffer = yaffs_get_temp_buffer(dev, __LINE__);
2149
2150                 yaffs_verify_blk(dev, bi, block);
2151
2152                 maxCopies = (wholeBlock) ? dev->param.chunks_per_block : 5;
2153                 oldChunk = block * dev->param.chunks_per_block + dev->gc_chunk;
2154
2155                 for (/* init already done */;
2156                      retVal == YAFFS_OK &&
2157                      dev->gc_chunk < dev->param.chunks_per_block &&
2158                      (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) &&
2159                      maxCopies > 0;
2160                      dev->gc_chunk++, oldChunk++) {
2161                         if (yaffs_check_chunk_bit(dev, block, dev->gc_chunk)) {
2162
2163                                 /* This page is in use and might need to be copied off */
2164
2165                                 maxCopies--;
2166
2167                                 mark_flash = 1;
2168
2169                                 yaffs_init_tags(&tags);
2170
2171                                 yaffs_rd_chunk_tags_nand(dev, oldChunk,
2172                                                                 buffer, &tags);
2173
2174                                 object =
2175                                     yaffs_find_by_number(dev,
2176                                                              tags.obj_id);
2177
2178                                 T(YAFFS_TRACE_GC_DETAIL,
2179                                   (TSTR
2180                                    ("Collecting chunk in block %d, %d %d %d " TENDSTR),
2181                                    dev->gc_chunk, tags.obj_id, tags.chunk_id,
2182                                    tags.n_bytes));
2183
2184                                 if (object && !yaffs_skip_verification(dev)) {
2185                                         if (tags.chunk_id == 0)
2186                                                 matchingChunk = object->hdr_chunk;
2187                                         else if (object->soft_del)
2188                                                 matchingChunk = oldChunk; /* Defeat the test */
2189                                         else
2190                                                 matchingChunk = yaffs_find_chunk_in_file(object, tags.chunk_id, NULL);
2191
2192                                         if (oldChunk != matchingChunk)
2193                                                 T(YAFFS_TRACE_ERROR,
2194                                                   (TSTR("gc: page in gc mismatch: %d %d %d %d"TENDSTR),
2195                                                   oldChunk, matchingChunk, tags.obj_id, tags.chunk_id));
2196
2197                                 }
2198
2199                                 if (!object) {
2200                                         T(YAFFS_TRACE_ERROR,
2201                                           (TSTR
2202                                            ("page %d in gc has no object: %d %d %d "
2203                                             TENDSTR), oldChunk,
2204                                             tags.obj_id, tags.chunk_id, tags.n_bytes));
2205                                 }
2206
2207                                 if (object &&
2208                                     object->deleted &&
2209                                     object->soft_del &&
2210                                     tags.chunk_id != 0) {
2211                                         /* Data chunk in a soft deleted file, throw it away
2212                                          * It's a soft deleted data chunk,
2213                                          * No need to copy this, just forget about it and
2214                                          * fix up the object.
2215                                          */
2216
2217                                         /* Free chunks already includes softdeleted chunks.
2218                                          * How ever this chunk is going to soon be really deleted
2219                                          * which will increment free chunks.
2220                                          * We have to decrement free chunks so this works out properly.
2221                                          */
2222                                         dev->n_free_chunks--;
2223                                         bi->soft_del_pages--;
2224
2225                                         object->n_data_chunks--;
2226
2227                                         if (object->n_data_chunks <= 0) {
2228                                                 /* remeber to clean up the object */
2229                                                 dev->gc_cleanup_list[dev->n_clean_ups] =
2230                                                     tags.obj_id;
2231                                                 dev->n_clean_ups++;
2232                                         }
2233                                         mark_flash = 0;
2234                                 } else if (0) {
2235                                         /* Todo object && object->deleted && object->n_data_chunks == 0 */
2236                                         /* Deleted object header with no data chunks.
2237                                          * Can be discarded and the file deleted.
2238                                          */
2239                                         object->hdr_chunk = 0;
2240                                         yaffs_free_tnode(object->my_dev,
2241                                                         object->variant.
2242                                                         file_variant.top);
2243                                         object->variant.file_variant.top = NULL;
2244                                         yaffs_generic_obj_del(object);
2245
2246                                 } else if (object) {
2247                                         /* It's either a data chunk in a live file or
2248                                          * an ObjectHeader, so we're interested in it.
2249                                          * NB Need to keep the ObjectHeaders of deleted files
2250                                          * until the whole file has been deleted off
2251                                          */
2252                                         tags.serial_number++;
2253
2254                                         dev->n_gc_copies++;
2255
2256                                         if (tags.chunk_id == 0) {
2257                                                 /* It is an object Id,
2258                                                  * We need to nuke the shrinkheader flags first
2259                                                  * Also need to clean up shadowing.
2260                                                  * We no longer want the shrinkHeader flag since its work is done
2261                                                  * and if it is left in place it will mess up scanning.
2262                                                  */
2263
2264                                                 yaffs_obj_header *oh;
2265                                                 oh = (yaffs_obj_header *)buffer;
2266
2267                                                 oh->is_shrink = 0;
2268                                                 tags.extra_is_shrink = 0;
2269
2270                                                 oh->shadows_obj = 0;
2271                                                 oh->inband_shadowed_obj_id = 0;
2272                                                 tags.extra_shadows = 0;
2273
2274                                                 /* Update file size */
2275                                                 if(object->variant_type == YAFFS_OBJECT_TYPE_FILE){
2276                                                         oh->file_size = object->variant.file_variant.file_size;
2277                                                         tags.extra_length = oh->file_size;
2278                                                 }
2279
2280                                                 yaffs_verify_oh(object, oh, &tags, 1);
2281                                                 newChunk =
2282                                                     yaffs_write_new_chunk(dev,(__u8 *) oh, &tags, 1);
2283                                         } else
2284                                                 newChunk =
2285                                                     yaffs_write_new_chunk(dev, buffer, &tags, 1);
2286
2287                                         if (newChunk < 0) {
2288                                                 retVal = YAFFS_FAIL;
2289                                         } else {
2290
2291                                                 /* Ok, now fix up the Tnodes etc. */
2292
2293                                                 if (tags.chunk_id == 0) {
2294                                                         /* It's a header */
2295                                                         object->hdr_chunk =  newChunk;
2296                                                         object->serial =   tags.serial_number;
2297                                                 } else {
2298                                                         /* It's a data chunk */
2299                                                         int ok;
2300                                                         ok = yaffs_put_chunk_in_file
2301                                                             (object,
2302                                                              tags.chunk_id,
2303                                                              newChunk, 0);
2304                                                 }
2305                                         }
2306                                 }
2307
2308                                 if (retVal == YAFFS_OK)
2309                                         yaffs_chunk_del(dev, oldChunk, mark_flash, __LINE__);
2310
2311                         }
2312                 }
2313
2314                 yaffs_release_temp_buffer(dev, buffer, __LINE__);
2315
2316
2317
2318         }
2319
2320         yaffs_verify_collected_blk(dev, bi, block);
2321
2322
2323
2324         if (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
2325                 /*
2326                  * The gc did not complete. Set block state back to FULL
2327                  * because checkpointing does not restore gc.
2328                  */
2329                 bi->block_state = YAFFS_BLOCK_STATE_FULL;
2330         } else {
2331                 /* The gc completed. */
2332                 /* Do any required cleanups */
2333                 for (i = 0; i < dev->n_clean_ups; i++) {
2334                         /* Time to delete the file too */
2335                         object =
2336                             yaffs_find_by_number(dev,
2337                                                      dev->gc_cleanup_list[i]);
2338                         if (object) {
2339                                 yaffs_free_tnode(dev,
2340                                                 object->variant.file_variant.
2341                                                 top);
2342                                 object->variant.file_variant.top = NULL;
2343                                 T(YAFFS_TRACE_GC,
2344                                   (TSTR
2345                                    ("yaffs: About to finally delete object %d"
2346                                     TENDSTR), object->obj_id));
2347                                 yaffs_generic_obj_del(object);
2348                                 object->my_dev->n_deleted_files--;
2349                         }
2350
2351                 }
2352
2353
2354                 chunksAfter = yaffs_get_erased_chunks(dev);
2355                 if (chunksBefore >= chunksAfter) {
2356                         T(YAFFS_TRACE_GC,
2357                           (TSTR
2358                            ("gc did not increase free chunks before %d after %d"
2359                             TENDSTR), chunksBefore, chunksAfter));
2360                 }
2361                 dev->gc_block = 0;
2362                 dev->gc_chunk = 0;
2363                 dev->n_clean_ups = 0;
2364         }
2365
2366         dev->gc_disable = 0;
2367
2368         return retVal;
2369 }
2370
2371 /*
2372  * FindBlockForgarbageCollection is used to select the dirtiest block (or close enough)
2373  * for garbage collection.
2374  */
2375
2376 static unsigned yaffs_find_gc_block(yaffs_dev_t *dev,
2377                                         int aggressive,
2378                                         int background)
2379 {
2380         int i;
2381         int iterations;
2382         unsigned selected = 0;
2383         int prioritised = 0;
2384         int prioritisedExists = 0;
2385         yaffs_block_info_t *bi;
2386         int threshold;
2387
2388         /* First let's see if we need to grab a prioritised block */
2389         if (dev->has_pending_prioritised_gc && !aggressive) {
2390                 dev->gc_dirtiest = 0;
2391                 bi = dev->block_info;
2392                 for (i = dev->internal_start_block;
2393                         i <= dev->internal_end_block && !selected;
2394                         i++) {
2395
2396                         if (bi->gc_prioritise) {
2397                                 prioritisedExists = 1;
2398                                 if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2399                                    yaffs_block_ok_for_gc(dev, bi)) {
2400                                         selected = i;
2401                                         prioritised = 1;
2402                                 }
2403                         }
2404                         bi++;
2405                 }
2406
2407                 /*
2408                  * If there is a prioritised block and none was selected then
2409                  * this happened because there is at least one old dirty block gumming
2410                  * up the works. Let's gc the oldest dirty block.
2411                  */
2412
2413                 if(prioritisedExists &&
2414                         !selected &&
2415                         dev->oldest_dirty_block > 0)
2416                         selected = dev->oldest_dirty_block;
2417
2418                 if (!prioritisedExists) /* None found, so we can clear this */
2419                         dev->has_pending_prioritised_gc = 0;
2420         }
2421
2422         /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
2423          * search harder.
2424          * else (we're doing a leasurely gc), then we only bother to do this if the
2425          * block has only a few pages in use.
2426          */
2427
2428         if (!selected){
2429                 int pagesUsed;
2430                 int nBlocks = dev->internal_end_block - dev->internal_start_block + 1;
2431                 if (aggressive){
2432                         threshold = dev->param.chunks_per_block;
2433                         iterations = nBlocks;
2434                 } else {
2435                         int maxThreshold;
2436
2437                         if(background)
2438                                 maxThreshold = dev->param.chunks_per_block/2;
2439                         else
2440                                 maxThreshold = dev->param.chunks_per_block/8;
2441
2442                         if(maxThreshold <  YAFFS_GC_PASSIVE_THRESHOLD)
2443                                 maxThreshold = YAFFS_GC_PASSIVE_THRESHOLD;
2444
2445                         threshold = background ?
2446                                 (dev->gc_not_done + 2) * 2 : 0;
2447                         if(threshold <YAFFS_GC_PASSIVE_THRESHOLD)
2448                                 threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2449                         if(threshold > maxThreshold)
2450                                 threshold = maxThreshold;
2451
2452                         iterations = nBlocks / 16 + 1;
2453                         if (iterations > 100)
2454                                 iterations = 100;
2455                 }
2456
2457                 for (i = 0;
2458                         i < iterations &&
2459                         (dev->gc_dirtiest < 1 ||
2460                                 dev->gc_pages_in_use > YAFFS_GC_GOOD_ENOUGH);
2461                         i++) {
2462                         dev->gc_block_finder++;
2463                         if (dev->gc_block_finder < dev->internal_start_block ||
2464                                 dev->gc_block_finder > dev->internal_end_block)
2465                                 dev->gc_block_finder = dev->internal_start_block;
2466
2467                         bi = yaffs_get_block_info(dev, dev->gc_block_finder);
2468
2469                         pagesUsed = bi->pages_in_use - bi->soft_del_pages;
2470
2471                         if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2472                                 pagesUsed < dev->param.chunks_per_block &&
2473                                 (dev->gc_dirtiest < 1 || pagesUsed < dev->gc_pages_in_use) &&
2474                                 yaffs_block_ok_for_gc(dev, bi)) {
2475                                 dev->gc_dirtiest = dev->gc_block_finder;
2476                                 dev->gc_pages_in_use = pagesUsed;
2477                         }
2478                 }
2479
2480                 if(dev->gc_dirtiest > 0 && dev->gc_pages_in_use <= threshold)
2481                         selected = dev->gc_dirtiest;
2482         }
2483
2484         /*
2485          * If nothing has been selected for a while, try selecting the oldest dirty
2486          * because that's gumming up the works.
2487          */
2488
2489         if(!selected && dev->param.is_yaffs2 &&
2490                 dev->gc_not_done >= ( background ? 10 : 20)){
2491                 yaffs2_find_oldest_dirty_seq(dev);
2492                 if(dev->oldest_dirty_block > 0) {
2493                         selected = dev->oldest_dirty_block;
2494                         dev->gc_dirtiest = selected;
2495                         dev->oldest_dirty_gc_count++;
2496                         bi = yaffs_get_block_info(dev, selected);
2497                         dev->gc_pages_in_use =  bi->pages_in_use - bi->soft_del_pages;
2498                 } else
2499                         dev->gc_not_done = 0;
2500         }
2501
2502         if(selected){
2503                 T(YAFFS_TRACE_GC,
2504                   (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR),
2505                   selected,
2506                   dev->param.chunks_per_block - dev->gc_pages_in_use,
2507                   prioritised));
2508
2509                 dev->n_gc_blocks++;
2510                 if(background)
2511                         dev->bg_gcs++;
2512
2513                 dev->gc_dirtiest = 0;
2514                 dev->gc_pages_in_use = 0;
2515                 dev->gc_not_done = 0;
2516                 if(dev->refresh_skip > 0)
2517                         dev->refresh_skip--;
2518         } else{
2519                 dev->gc_not_done++;
2520                 T(YAFFS_TRACE_GC,
2521                   (TSTR("GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s" TENDSTR),
2522                   dev->gc_block_finder, dev->gc_not_done,
2523                   threshold,
2524                   dev->gc_dirtiest, dev->gc_pages_in_use,
2525                   dev->oldest_dirty_block,
2526                   background ? " bg" : ""));
2527         }
2528
2529         return selected;
2530 }
2531
2532 /* New garbage collector
2533  * If we're very low on erased blocks then we do aggressive garbage collection
2534  * otherwise we do "leasurely" garbage collection.
2535  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2536  * Passive gc only inspects smaller areas and will only accept more dirty blocks.
2537  *
2538  * The idea is to help clear out space in a more spread-out manner.
2539  * Dunno if it really does anything useful.
2540  */
2541 static int yaffs_check_gc(yaffs_dev_t *dev, int background)
2542 {
2543         int aggressive = 0;
2544         int gcOk = YAFFS_OK;
2545         int maxTries = 0;
2546         int minErased;
2547         int erasedChunks;
2548         int checkpointBlockAdjust;
2549
2550         if(dev->param.gc_control &&
2551                 (dev->param.gc_control(dev) & 1) == 0)
2552                 return YAFFS_OK;
2553
2554         if (dev->gc_disable) {
2555                 /* Bail out so we don't get recursive gc */
2556                 return YAFFS_OK;
2557         }
2558
2559         /* This loop should pass the first time.
2560          * We'll only see looping here if the collection does not increase space.
2561          */
2562
2563         do {
2564                 maxTries++;
2565
2566                 checkpointBlockAdjust = yaffs_calc_checkpt_blocks_required(dev);
2567
2568                 minErased  = dev->param.n_reserved_blocks + checkpointBlockAdjust + 1;
2569                 erasedChunks = dev->n_erased_blocks * dev->param.chunks_per_block;
2570
2571                 /* If we need a block soon then do aggressive gc.*/
2572                 if (dev->n_erased_blocks < minErased)
2573                         aggressive = 1;
2574                 else {
2575                         if(!background && erasedChunks > (dev->n_free_chunks / 4))
2576                                 break;
2577
2578                         if(dev->gc_skip > 20)
2579                                 dev->gc_skip = 20;
2580                         if(erasedChunks < dev->n_free_chunks/2 ||
2581                                 dev->gc_skip < 1 ||
2582                                 background)
2583                                 aggressive = 0;
2584                         else {
2585                                 dev->gc_skip--;
2586                                 break;
2587                         }
2588                 }
2589
2590                 dev->gc_skip = 5;
2591
2592                 /* If we don't already have a block being gc'd then see if we should start another */
2593
2594                 if (dev->gc_block < 1 && !aggressive) {
2595                         dev->gc_block = yaffs2_find_refresh_block(dev);
2596                         dev->gc_chunk = 0;
2597                         dev->n_clean_ups=0;
2598                 }
2599                 if (dev->gc_block < 1) {
2600                         dev->gc_block = yaffs_find_gc_block(dev, aggressive, background);
2601                         dev->gc_chunk = 0;
2602                         dev->n_clean_ups=0;
2603                 }
2604
2605                 if (dev->gc_block > 0) {
2606                         dev->all_gcs++;
2607                         if (!aggressive)
2608                                 dev->passive_gc_count++;
2609
2610                         T(YAFFS_TRACE_GC,
2611                           (TSTR
2612                            ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
2613                            dev->n_erased_blocks, aggressive));
2614
2615                         gcOk = yaffs_gc_block(dev, dev->gc_block, aggressive);
2616                 }
2617
2618                 if (dev->n_erased_blocks < (dev->param.n_reserved_blocks) && dev->gc_block > 0) {
2619                         T(YAFFS_TRACE_GC,
2620                           (TSTR
2621                            ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
2622                             TENDSTR), dev->n_erased_blocks, maxTries, dev->gc_block));
2623                 }
2624         } while ((dev->n_erased_blocks < dev->param.n_reserved_blocks) &&
2625                  (dev->gc_block > 0) &&
2626                  (maxTries < 2));
2627
2628         return aggressive ? gcOk : YAFFS_OK;
2629 }
2630
2631 /*
2632  * yaffs_bg_gc()
2633  * Garbage collects. Intended to be called from a background thread.
2634  * Returns non-zero if at least half the free chunks are erased.
2635  */
2636 int yaffs_bg_gc(yaffs_dev_t *dev, unsigned urgency)
2637 {
2638         int erasedChunks = dev->n_erased_blocks * dev->param.chunks_per_block;
2639
2640         T(YAFFS_TRACE_BACKGROUND, (TSTR("Background gc %u" TENDSTR),urgency));
2641
2642         yaffs_check_gc(dev, 1);
2643         return erasedChunks > dev->n_free_chunks/2;
2644 }
2645
2646 /*-------------------------  TAGS --------------------------------*/
2647
2648 static int yaffs_tags_match(const yaffs_ext_tags *tags, int obj_id,
2649                            int chunkInObject)
2650 {
2651         return (tags->chunk_id == chunkInObject &&
2652                 tags->obj_id == obj_id && !tags->is_deleted) ? 1 : 0;
2653
2654 }
2655
2656
2657 /*-------------------- Data file manipulation -----------------*/
2658
2659 static int yaffs_find_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
2660                                  yaffs_ext_tags *tags)
2661 {
2662         /*Get the Tnode, then get the level 0 offset chunk offset */
2663         yaffs_tnode_t *tn;
2664         int theChunk = -1;
2665         yaffs_ext_tags localTags;
2666         int retVal = -1;
2667
2668         yaffs_dev_t *dev = in->my_dev;
2669
2670         if (!tags) {
2671                 /* Passed a NULL, so use our own tags space */
2672                 tags = &localTags;
2673         }
2674
2675         tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
2676
2677         if (tn) {
2678                 theChunk = yaffs_get_group_base(dev, tn, inode_chunk);
2679
2680                 retVal =
2681                     yaffs_find_chunk_in_group(dev, theChunk, tags, in->obj_id,
2682                                            inode_chunk);
2683         }
2684         return retVal;
2685 }
2686
2687 static int yaffs_find_del_file_chunk(yaffs_obj_t *in, int inode_chunk,
2688                                           yaffs_ext_tags *tags)
2689 {
2690         /* Get the Tnode, then get the level 0 offset chunk offset */
2691         yaffs_tnode_t *tn;
2692         int theChunk = -1;
2693         yaffs_ext_tags localTags;
2694
2695         yaffs_dev_t *dev = in->my_dev;
2696         int retVal = -1;
2697
2698         if (!tags) {
2699                 /* Passed a NULL, so use our own tags space */
2700                 tags = &localTags;
2701         }
2702
2703         tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
2704
2705         if (tn) {
2706
2707                 theChunk = yaffs_get_group_base(dev, tn, inode_chunk);
2708
2709                 retVal =
2710                     yaffs_find_chunk_in_group(dev, theChunk, tags, in->obj_id,
2711                                            inode_chunk);
2712
2713                 /* Delete the entry in the filestructure (if found) */
2714                 if (retVal != -1)
2715                         yaffs_load_tnode_0(dev, tn, inode_chunk, 0);
2716         }
2717
2718         return retVal;
2719 }
2720
2721
2722 int yaffs_put_chunk_in_file(yaffs_obj_t *in, int inode_chunk,
2723                                 int nand_chunk, int in_scan)
2724 {
2725         /* NB in_scan is zero unless scanning.
2726          * For forward scanning, in_scan is > 0;
2727          * for backward scanning in_scan is < 0
2728          *
2729          * nand_chunk = 0 is a dummy insert to make sure the tnodes are there.
2730          */
2731
2732         yaffs_tnode_t *tn;
2733         yaffs_dev_t *dev = in->my_dev;
2734         int existingChunk;
2735         yaffs_ext_tags existingTags;
2736         yaffs_ext_tags newTags;
2737         unsigned existingSerial, newSerial;
2738
2739         if (in->variant_type != YAFFS_OBJECT_TYPE_FILE) {
2740                 /* Just ignore an attempt at putting a chunk into a non-file during scanning
2741                  * If it is not during Scanning then something went wrong!
2742                  */
2743                 if (!in_scan) {
2744                         T(YAFFS_TRACE_ERROR,
2745                           (TSTR
2746                            ("yaffs tragedy:attempt to put data chunk into a non-file"
2747                             TENDSTR)));
2748                         YBUG();
2749                 }
2750
2751                 yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
2752                 return YAFFS_OK;
2753         }
2754
2755         tn = yaffs_add_find_tnode_0(dev,
2756                                         &in->variant.file_variant,
2757                                         inode_chunk,
2758                                         NULL);
2759         if (!tn)
2760                 return YAFFS_FAIL;
2761
2762         if(!nand_chunk)
2763                 /* Dummy insert, bail now */
2764                 return YAFFS_OK;
2765
2766         existingChunk = yaffs_get_group_base(dev, tn, inode_chunk);
2767
2768         if (in_scan != 0) {
2769                 /* If we're scanning then we need to test for duplicates
2770                  * NB This does not need to be efficient since it should only ever
2771                  * happen when the power fails during a write, then only one
2772                  * chunk should ever be affected.
2773                  *
2774                  * Correction for YAFFS2: This could happen quite a lot and we need to think about efficiency! TODO
2775                  * Update: For backward scanning we don't need to re-read tags so this is quite cheap.
2776                  */
2777
2778                 if (existingChunk > 0) {
2779                         /* NB Right now existing chunk will not be real chunk_id if the chunk group size > 1
2780                          *    thus we have to do a FindChunkInFile to get the real chunk id.
2781                          *
2782                          * We have a duplicate now we need to decide which one to use:
2783                          *
2784                          * Backwards scanning YAFFS2: The old one is what we use, dump the new one.
2785                          * Forward scanning YAFFS2: The new one is what we use, dump the old one.
2786                          * YAFFS1: Get both sets of tags and compare serial numbers.
2787                          */
2788
2789                         if (in_scan > 0) {
2790                                 /* Only do this for forward scanning */
2791                                 yaffs_rd_chunk_tags_nand(dev,
2792                                                                 nand_chunk,
2793                                                                 NULL, &newTags);
2794
2795                                 /* Do a proper find */
2796                                 existingChunk =
2797                                     yaffs_find_chunk_in_file(in, inode_chunk,
2798                                                           &existingTags);
2799                         }
2800
2801                         if (existingChunk <= 0) {
2802                                 /*Hoosterman - how did this happen? */
2803
2804                                 T(YAFFS_TRACE_ERROR,
2805                                   (TSTR
2806                                    ("yaffs tragedy: existing chunk < 0 in scan"
2807                                     TENDSTR)));
2808
2809                         }
2810
2811                         /* NB The deleted flags should be false, otherwise the chunks will
2812                          * not be loaded during a scan
2813                          */
2814
2815                         if (in_scan > 0) {
2816                                 newSerial = newTags.serial_number;
2817                                 existingSerial = existingTags.serial_number;
2818                         }
2819
2820                         if ((in_scan > 0) &&
2821                             (existingChunk <= 0 ||
2822                              ((existingSerial + 1) & 3) == newSerial)) {
2823                                 /* Forward scanning.
2824                                  * Use new
2825                                  * Delete the old one and drop through to update the tnode
2826                                  */
2827                                 yaffs_chunk_del(dev, existingChunk, 1,
2828                                                   __LINE__);
2829                         } else {
2830                                 /* Backward scanning or we want to use the existing one
2831                                  * Use existing.
2832                                  * Delete the new one and return early so that the tnode isn't changed
2833                                  */
2834                                 yaffs_chunk_del(dev, nand_chunk, 1,
2835                                                   __LINE__);
2836                                 return YAFFS_OK;
2837                         }
2838                 }
2839
2840         }
2841
2842         if (existingChunk == 0)
2843                 in->n_data_chunks++;
2844
2845         yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
2846
2847         return YAFFS_OK;
2848 }
2849
2850 static int yaffs_rd_data_obj(yaffs_obj_t *in, int inode_chunk,
2851                                         __u8 *buffer)
2852 {
2853         int nand_chunk = yaffs_find_chunk_in_file(in, inode_chunk, NULL);
2854
2855         if (nand_chunk >= 0)
2856                 return yaffs_rd_chunk_tags_nand(in->my_dev, nand_chunk,
2857                                                 buffer, NULL);
2858         else {
2859                 T(YAFFS_TRACE_NANDACCESS,
2860                   (TSTR("Chunk %d not found zero instead" TENDSTR),
2861                    nand_chunk));
2862                 /* get sane (zero) data if you read a hole */
2863                 memset(buffer, 0, in->my_dev->data_bytes_per_chunk);
2864                 return 0;
2865         }
2866
2867 }
2868
2869 void yaffs_chunk_del(yaffs_dev_t *dev, int chunk_id, int mark_flash, int lyn)
2870 {
2871         int block;
2872         int page;
2873         yaffs_ext_tags tags;
2874         yaffs_block_info_t *bi;
2875
2876         if (chunk_id <= 0)
2877                 return;
2878
2879         dev->n_deletions++;
2880         block = chunk_id / dev->param.chunks_per_block;
2881         page = chunk_id % dev->param.chunks_per_block;
2882
2883
2884         if (!yaffs_check_chunk_bit(dev, block, page))
2885                 T(YAFFS_TRACE_VERIFY,
2886                         (TSTR("Deleting invalid chunk %d"TENDSTR),
2887                          chunk_id));
2888
2889         bi = yaffs_get_block_info(dev, block);
2890
2891         yaffs2_update_oldest_dirty_seq(dev, block, bi);
2892
2893         T(YAFFS_TRACE_DELETION,
2894           (TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunk_id));
2895
2896         if (!dev->param.is_yaffs2 && mark_flash &&
2897             bi->block_state != YAFFS_BLOCK_STATE_COLLECTING) {
2898
2899                 yaffs_init_tags(&tags);
2900
2901                 tags.is_deleted = 1;
2902
2903                 yaffs_wr_chunk_tags_nand(dev, chunk_id, NULL, &tags);
2904                 yaffs_handle_chunk_update(dev, chunk_id, &tags);
2905         } else {
2906                 dev->n_unmarked_deletions++;
2907         }
2908
2909         /* Pull out of the management area.
2910          * If the whole block became dirty, this will kick off an erasure.
2911          */
2912         if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING ||
2913             bi->block_state == YAFFS_BLOCK_STATE_FULL ||
2914             bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCANNING ||
2915             bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
2916                 dev->n_free_chunks++;
2917
2918                 yaffs_clear_chunk_bit(dev, block, page);
2919
2920                 bi->pages_in_use--;
2921
2922                 if (bi->pages_in_use == 0 &&
2923                     !bi->has_shrink_hdr &&
2924                     bi->block_state != YAFFS_BLOCK_STATE_ALLOCATING &&
2925                     bi->block_state != YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
2926                         yaffs_block_became_dirty(dev, block);
2927                 }
2928
2929         }
2930
2931 }
2932
2933 static int yaffs_wr_data_obj(yaffs_obj_t *in, int inode_chunk,
2934                                         const __u8 *buffer, int n_bytes,
2935                                         int useReserve)
2936 {
2937         /* Find old chunk Need to do this to get serial number
2938          * Write new one and patch into tree.
2939          * Invalidate old tags.
2940          */
2941
2942         int prevChunkId;
2943         yaffs_ext_tags prevTags;
2944
2945         int newChunkId;
2946         yaffs_ext_tags newTags;
2947
2948         yaffs_dev_t *dev = in->my_dev;
2949
2950         yaffs_check_gc(dev,0);
2951
2952         /* Get the previous chunk at this location in the file if it exists.
2953          * If it does not exist then put a zero into the tree. This creates
2954          * the tnode now, rather than later when it is harder to clean up.
2955          */
2956         prevChunkId = yaffs_find_chunk_in_file(in, inode_chunk, &prevTags);
2957         if(prevChunkId < 1 &&
2958                 !yaffs_put_chunk_in_file(in, inode_chunk, 0, 0))
2959                 return 0;
2960
2961         /* Set up new tags */
2962         yaffs_init_tags(&newTags);
2963
2964         newTags.chunk_id = inode_chunk;
2965         newTags.obj_id = in->obj_id;
2966         newTags.serial_number =
2967             (prevChunkId > 0) ? prevTags.serial_number + 1 : 1;
2968         newTags.n_bytes = n_bytes;
2969
2970         if (n_bytes < 1 || n_bytes > dev->param.total_bytes_per_chunk) {
2971                 T(YAFFS_TRACE_ERROR,
2972                 (TSTR("Writing %d bytes to chunk!!!!!!!!!" TENDSTR), n_bytes));
2973                 YBUG();
2974         }
2975
2976
2977         newChunkId =
2978             yaffs_write_new_chunk(dev, buffer, &newTags,
2979                                               useReserve);
2980
2981         if (newChunkId > 0) {
2982                 yaffs_put_chunk_in_file(in, inode_chunk, newChunkId, 0);
2983
2984                 if (prevChunkId > 0)
2985                         yaffs_chunk_del(dev, prevChunkId, 1, __LINE__);
2986
2987                 yaffs_verify_file_sane(in);
2988         }
2989         return newChunkId;
2990
2991 }
2992
2993 /* UpdateObjectHeader updates the header on NAND for an object.
2994  * If name is not NULL, then that new name is used.
2995  */
2996 int yaffs_update_oh(yaffs_obj_t *in, const YCHAR *name, int force,
2997                              int is_shrink, int shadows, yaffs_xattr_mod *xmod)
2998 {
2999
3000         yaffs_block_info_t *bi;
3001
3002         yaffs_dev_t *dev = in->my_dev;
3003
3004         int prevChunkId;
3005         int retVal = 0;
3006         int result = 0;
3007
3008         int newChunkId;
3009         yaffs_ext_tags newTags;
3010         yaffs_ext_tags oldTags;
3011         const YCHAR *alias = NULL;
3012
3013         __u8 *buffer = NULL;
3014         YCHAR old_name[YAFFS_MAX_NAME_LENGTH + 1];
3015
3016         yaffs_obj_header *oh = NULL;
3017
3018         yaffs_strcpy(old_name, _Y("silly old name"));
3019
3020
3021         if (!in->fake ||
3022                 in == dev->root_dir || /* The root_dir should also be saved */
3023                 force  || xmod) {
3024
3025                 yaffs_check_gc(dev,0);
3026                 yaffs_check_obj_details_loaded(in);
3027
3028                 buffer = yaffs_get_temp_buffer(in->my_dev, __LINE__);
3029                 oh = (yaffs_obj_header *) buffer;
3030
3031                 prevChunkId = in->hdr_chunk;
3032
3033                 if (prevChunkId > 0) {
3034                         result = yaffs_rd_chunk_tags_nand(dev, prevChunkId,
3035                                                         buffer, &oldTags);
3036
3037                         yaffs_verify_oh(in, oh, &oldTags, 0);
3038
3039                         memcpy(old_name, oh->name, sizeof(oh->name));
3040                         memset(buffer, 0xFF, sizeof(yaffs_obj_header));
3041                 } else
3042                         memset(buffer, 0xFF, dev->data_bytes_per_chunk);
3043
3044                 oh->type = in->variant_type;
3045                 oh->yst_mode = in->yst_mode;
3046                 oh->shadows_obj = oh->inband_shadowed_obj_id = shadows;
3047
3048 #ifdef CONFIG_YAFFS_WINCE
3049                 oh->win_atime[0] = in->win_atime[0];
3050                 oh->win_ctime[0] = in->win_ctime[0];
3051                 oh->win_mtime[0] = in->win_mtime[0];
3052                 oh->win_atime[1] = in->win_atime[1];
3053                 oh->win_ctime[1] = in->win_ctime[1];
3054                 oh->win_mtime[1] = in->win_mtime[1];
3055 #else
3056                 oh->yst_uid = in->yst_uid;
3057                 oh->yst_gid = in->yst_gid;
3058                 oh->yst_atime = in->yst_atime;
3059                 oh->yst_mtime = in->yst_mtime;
3060                 oh->yst_ctime = in->yst_ctime;
3061                 oh->yst_rdev = in->yst_rdev;
3062 #endif
3063                 if (in->parent)
3064                         oh->parent_obj_id = in->parent->obj_id;
3065                 else
3066                         oh->parent_obj_id = 0;
3067
3068                 if (name && *name) {
3069                         memset(oh->name, 0, sizeof(oh->name));
3070                         yaffs_load_oh_from_name(dev,oh->name,name);
3071                 } else if (prevChunkId > 0)
3072                         memcpy(oh->name, old_name, sizeof(oh->name));
3073                 else
3074                         memset(oh->name, 0, sizeof(oh->name));
3075
3076                 oh->is_shrink = is_shrink;
3077
3078                 switch (in->variant_type) {
3079                 case YAFFS_OBJECT_TYPE_UNKNOWN:
3080                         /* Should not happen */
3081                         break;
3082                 case YAFFS_OBJECT_TYPE_FILE:
3083                         oh->file_size =
3084                             (oh->parent_obj_id == YAFFS_OBJECTID_DELETED
3085                              || oh->parent_obj_id ==
3086                              YAFFS_OBJECTID_UNLINKED) ? 0 : in->variant.
3087                             file_variant.file_size;
3088                         break;
3089                 case YAFFS_OBJECT_TYPE_HARDLINK:
3090                         oh->equiv_id =
3091                             in->variant.hardlink_variant.equiv_id;
3092                         break;
3093                 case YAFFS_OBJECT_TYPE_SPECIAL:
3094                         /* Do nothing */
3095                         break;
3096                 case YAFFS_OBJECT_TYPE_DIRECTORY:
3097                         /* Do nothing */
3098                         break;
3099                 case YAFFS_OBJECT_TYPE_SYMLINK:
3100                         alias = in->variant.symlink_variant.alias;
3101                         if(!alias)
3102                                 alias = _Y("no alias");
3103                         yaffs_strncpy(oh->alias,
3104                                         alias,
3105                                       YAFFS_MAX_ALIAS_LENGTH);
3106                         oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3107                         break;
3108                 }
3109
3110                 /* process any xattrib modifications */
3111                 if(xmod)
3112                         yaffs_apply_xattrib_mod(in, (char *)buffer, xmod);
3113
3114
3115                 /* Tags */
3116                 yaffs_init_tags(&newTags);
3117                 in->serial++;
3118                 newTags.chunk_id = 0;
3119                 newTags.obj_id = in->obj_id;
3120                 newTags.serial_number = in->serial;
3121
3122                 /* Add extra info for file header */
3123
3124                 newTags.extra_available = 1;
3125                 newTags.extra_parent_id = oh->parent_obj_id;
3126                 newTags.extra_length = oh->file_size;
3127                 newTags.extra_is_shrink = oh->is_shrink;
3128                 newTags.extra_equiv_id = oh->equiv_id;
3129                 newTags.extra_shadows = (oh->shadows_obj > 0) ? 1 : 0;
3130                 newTags.extra_obj_type = in->variant_type;
3131
3132                 yaffs_verify_oh(in, oh, &newTags, 1);
3133
3134                 /* Create new chunk in NAND */
3135                 newChunkId =
3136                     yaffs_write_new_chunk(dev, buffer, &newTags,
3137                                                       (prevChunkId > 0) ? 1 : 0);
3138
3139                 if (newChunkId >= 0) {
3140
3141                         in->hdr_chunk = newChunkId;
3142
3143                         if (prevChunkId > 0) {
3144                                 yaffs_chunk_del(dev, prevChunkId, 1,
3145                                                   __LINE__);
3146                         }
3147
3148                         if (!yaffs_obj_cache_dirty(in))
3149                                 in->dirty = 0;
3150
3151                         /* If this was a shrink, then mark the block that the chunk lives on */
3152                         if (is_shrink) {
3153                                 bi = yaffs_get_block_info(in->my_dev,
3154                                         newChunkId / in->my_dev->param.chunks_per_block);
3155                                 bi->has_shrink_hdr = 1;
3156                         }
3157
3158                 }
3159
3160                 retVal = newChunkId;
3161
3162         }
3163
3164         if (buffer)
3165                 yaffs_release_temp_buffer(dev, buffer, __LINE__);
3166
3167         return retVal;
3168 }
3169
3170 /*------------------------ Short Operations Cache ----------------------------------------
3171  *   In many situations where there is no high level buffering (eg WinCE) a lot of
3172  *   reads might be short sequential reads, and a lot of writes may be short
3173  *   sequential writes. eg. scanning/writing a jpeg file.
3174  *   In these cases, a short read/write cache can provide a huge perfomance benefit
3175  *   with dumb-as-a-rock code.
3176  *   In Linux, the page cache provides read buffering aand the short op cache provides write
3177  *   buffering.
3178  *
3179  *   There are a limited number (~10) of cache chunks per device so that we don't
3180  *   need a very intelligent search.
3181  */
3182
3183 static int yaffs_obj_cache_dirty(yaffs_obj_t *obj)
3184 {
3185         yaffs_dev_t *dev = obj->my_dev;
3186         int i;
3187         yaffs_cache_t *cache;
3188         int nCaches = obj->my_dev->param.n_caches;
3189
3190         for (i = 0; i < nCaches; i++) {
3191                 cache = &dev->cache[i];
3192                 if (cache->object == obj &&
3193                     cache->dirty)
3194                         return 1;
3195         }
3196
3197         return 0;
3198 }
3199
3200
3201 static void yaffs_flush_file_cache(yaffs_obj_t *obj)
3202 {
3203         yaffs_dev_t *dev = obj->my_dev;
3204         int lowest = -99;       /* Stop compiler whining. */
3205         int i;
3206         yaffs_cache_t *cache;
3207         int chunkWritten = 0;
3208         int nCaches = obj->my_dev->param.n_caches;
3209
3210         if (nCaches > 0) {
3211                 do {
3212                         cache = NULL;
3213
3214                         /* Find the dirty cache for this object with the lowest chunk id. */
3215                         for (i = 0; i < nCaches; i++) {
3216                                 if (dev->cache[i].object == obj &&
3217                                     dev->cache[i].dirty) {
3218                                         if (!cache
3219                                             || dev->cache[i].chunk_id <
3220                                             lowest) {
3221                                                 cache = &dev->cache[i];
3222                                                 lowest = cache->chunk_id;
3223                                         }
3224                                 }
3225                         }
3226
3227                         if (cache && !cache->locked) {
3228                                 /* Write it out and free it up */
3229
3230                                 chunkWritten =
3231                                     yaffs_wr_data_obj(cache->object,
3232                                                                  cache->chunk_id,
3233                                                                  cache->data,
3234                                                                  cache->n_bytes,
3235                                                                  1);
3236                                 cache->dirty = 0;
3237                                 cache->object = NULL;
3238                         }
3239
3240                 } while (cache && chunkWritten > 0);
3241
3242                 if (cache) {
3243                         /* Hoosterman, disk full while writing cache out. */
3244                         T(YAFFS_TRACE_ERROR,
3245                           (TSTR("yaffs tragedy: no space during cache write" TENDSTR)));
3246
3247                 }
3248         }
3249
3250 }
3251
3252 /*yaffs_flush_whole_cache(dev)
3253  *
3254  *
3255  */
3256
3257 void yaffs_flush_whole_cache(yaffs_dev_t *dev)
3258 {
3259         yaffs_obj_t *obj;
3260         int nCaches = dev->param.n_caches;
3261         int i;
3262
3263         /* Find a dirty object in the cache and flush it...
3264          * until there are no further dirty objects.
3265          */
3266         do {
3267                 obj = NULL;
3268                 for (i = 0; i < nCaches && !obj; i++) {
3269                         if (dev->cache[i].object &&
3270                             dev->cache[i].dirty)
3271                                 obj = dev->cache[i].object;
3272
3273                 }
3274                 if (obj)
3275                         yaffs_flush_file_cache(obj);
3276
3277         } while (obj);
3278
3279 }
3280
3281
3282 /* Grab us a cache chunk for use.
3283  * First look for an empty one.
3284  * Then look for the least recently used non-dirty one.
3285  * Then look for the least recently used dirty one...., flush and look again.
3286  */
3287 static yaffs_cache_t *yaffs_grab_chunk_worker(yaffs_dev_t *dev)
3288 {
3289         int i;
3290
3291         if (dev->param.n_caches > 0) {
3292                 for (i = 0; i < dev->param.n_caches; i++) {
3293                         if (!dev->cache[i].object)
3294                                 return &dev->cache[i];
3295                 }
3296         }
3297
3298         return NULL;
3299 }
3300
3301 static yaffs_cache_t *yaffs_grab_chunk_cache(yaffs_dev_t *dev)
3302 {
3303         yaffs_cache_t *cache;
3304         yaffs_obj_t *theObj;
3305         int usage;
3306         int i;
3307         int pushout;
3308
3309         if (dev->param.n_caches > 0) {
3310                 /* Try find a non-dirty one... */
3311
3312                 cache = yaffs_grab_chunk_worker(dev);
3313
3314                 if (!cache) {
3315                         /* They were all dirty, find the last recently used object and flush
3316                          * its cache, then  find again.
3317                          * NB what's here is not very accurate, we actually flush the object
3318                          * the last recently used page.
3319                          */
3320
3321                         /* With locking we can't assume we can use entry zero */
3322
3323                         theObj = NULL;
3324                         usage = -1;
3325                         cache = NULL;
3326                         pushout = -1;
3327
3328                         for (i = 0; i < dev->param.n_caches; i++) {
3329                                 if (dev->cache[i].object &&
3330                                     !dev->cache[i].locked &&
3331                                     (dev->cache[i].last_use < usage || !cache)) {
3332                                         usage = dev->cache[i].last_use;
3333                                         theObj = dev->cache[i].object;
3334                                         cache = &dev->cache[i];
3335                                         pushout = i;
3336                                 }
3337                         }
3338
3339                         if (!cache || cache->dirty) {
3340                                 /* Flush and try again */
3341                                 yaffs_flush_file_cache(theObj);
3342                                 cache = yaffs_grab_chunk_worker(dev);
3343                         }
3344
3345                 }
3346                 return cache;
3347         } else
3348                 return NULL;
3349
3350 }
3351
3352 /* Find a cached chunk */
3353 static yaffs_cache_t *yaffs_find_chunk_cache(const yaffs_obj_t *obj,
3354                                               int chunk_id)
3355 {
3356         yaffs_dev_t *dev = obj->my_dev;
3357         int i;
3358         if (dev->param.n_caches > 0) {
3359                 for (i = 0; i < dev->param.n_caches; i++) {
3360                         if (dev->cache[i].object == obj &&
3361                             dev->cache[i].chunk_id == chunk_id) {
3362                                 dev->cache_hits++;
3363
3364                                 return &dev->cache[i];
3365                         }
3366                 }
3367         }
3368         return NULL;
3369 }
3370
3371 /* Mark the chunk for the least recently used algorithym */
3372 static void yaffs_use_cache(yaffs_dev_t *dev, yaffs_cache_t *cache,
3373                                 int isAWrite)
3374 {
3375
3376         if (dev->param.n_caches > 0) {
3377                 if (dev->cache_last_use < 0 || dev->cache_last_use > 100000000) {
3378                         /* Reset the cache usages */
3379                         int i;
3380                         for (i = 1; i < dev->param.n_caches; i++)
3381                                 dev->cache[i].last_use = 0;
3382
3383                         dev->cache_last_use = 0;
3384                 }
3385
3386                 dev->cache_last_use++;
3387
3388                 cache->last_use = dev->cache_last_use;
3389
3390                 if (isAWrite)
3391                         cache->dirty = 1;
3392         }
3393 }
3394
3395 /* Invalidate a single cache page.
3396  * Do this when a whole page gets written,
3397  * ie the short cache for this page is no longer valid.
3398  */
3399 static void yaffs_invalidate_chunk_cache(yaffs_obj_t *object, int chunk_id)
3400 {
3401         if (object->my_dev->param.n_caches > 0) {
3402                 yaffs_cache_t *cache = yaffs_find_chunk_cache(object, chunk_id);
3403
3404                 if (cache)
3405                         cache->object = NULL;
3406         }
3407 }
3408
3409 /* Invalidate all the cache pages associated with this object
3410  * Do this whenever ther file is deleted or resized.
3411  */
3412 static void yaffs_invalidate_whole_cache(yaffs_obj_t *in)
3413 {
3414         int i;
3415         yaffs_dev_t *dev = in->my_dev;
3416
3417         if (dev->param.n_caches > 0) {
3418                 /* Invalidate it. */
3419                 for (i = 0; i < dev->param.n_caches; i++) {
3420                         if (dev->cache[i].object == in)
3421                                 dev->cache[i].object = NULL;
3422                 }
3423         }
3424 }
3425
3426
3427 /*--------------------- File read/write ------------------------
3428  * Read and write have very similar structures.
3429  * In general the read/write has three parts to it
3430  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3431  * Some complete chunks
3432  * An incomplete chunk to end off with
3433  *
3434  * Curve-balls: the first chunk might also be the last chunk.
3435  */
3436
3437 int yaffs_file_rd(yaffs_obj_t *in, __u8 *buffer, loff_t offset,
3438                         int n_bytes)
3439 {
3440
3441         int chunk;
3442         __u32 start;
3443         int nToCopy;
3444         int n = n_bytes;
3445         int nDone = 0;
3446         yaffs_cache_t *cache;
3447
3448         yaffs_dev_t *dev;
3449
3450         dev = in->my_dev;
3451
3452         while (n > 0) {
3453                 /* chunk = offset / dev->data_bytes_per_chunk + 1; */
3454                 /* start = offset % dev->data_bytes_per_chunk; */
3455                 yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3456                 chunk++;
3457
3458                 /* OK now check for the curveball where the start and end are in
3459                  * the same chunk.
3460                  */
3461                 if ((start + n) < dev->data_bytes_per_chunk)
3462                         nToCopy = n;
3463                 else
3464                         nToCopy = dev->data_bytes_per_chunk - start;
3465
3466                 cache = yaffs_find_chunk_cache(in, chunk);
3467
3468                 /* If the chunk is already in the cache or it is less than a whole chunk
3469                  * or we're using inband tags then use the cache (if there is caching)
3470                  * else bypass the cache.
3471                  */
3472                 if (cache || nToCopy != dev->data_bytes_per_chunk || dev->param.inband_tags) {
3473                         if (dev->param.n_caches > 0) {
3474
3475                                 /* If we can't find the data in the cache, then load it up. */
3476
3477                                 if (!cache) {
3478                                         cache = yaffs_grab_chunk_cache(in->my_dev);
3479                                         cache->object = in;
3480                                         cache->chunk_id = chunk;
3481                                         cache->dirty = 0;
3482                                         cache->locked = 0;
3483                                         yaffs_rd_data_obj(in, chunk,
3484                                                                       cache->
3485                                                                       data);
3486                                         cache->n_bytes = 0;
3487                                 }
3488
3489                                 yaffs_use_cache(dev, cache, 0);
3490
3491                                 cache->locked = 1;
3492
3493
3494                                 memcpy(buffer, &cache->data[start], nToCopy);
3495
3496                                 cache->locked = 0;
3497                         } else {
3498                                 /* Read into the local buffer then copy..*/
3499
3500                                 __u8 *localBuffer =
3501                                     yaffs_get_temp_buffer(dev, __LINE__);
3502                                 yaffs_rd_data_obj(in, chunk,
3503                                                               localBuffer);
3504
3505                                 memcpy(buffer, &localBuffer[start], nToCopy);
3506
3507
3508                                 yaffs_release_temp_buffer(dev, localBuffer,
3509                                                         __LINE__);
3510                         }
3511
3512                 } else {
3513
3514                         /* A full chunk. Read directly into the supplied buffer. */
3515                         yaffs_rd_data_obj(in, chunk, buffer);
3516
3517                 }
3518
3519                 n -= nToCopy;
3520                 offset += nToCopy;
3521                 buffer += nToCopy;
3522                 nDone += nToCopy;
3523
3524         }
3525
3526         return nDone;
3527 }
3528
3529 int yaffs_do_file_wr(yaffs_obj_t *in, const __u8 *buffer, loff_t offset,
3530                         int n_bytes, int write_trhrough)
3531 {
3532
3533         int chunk;
3534         __u32 start;
3535         int nToCopy;
3536         int n = n_bytes;
3537         int nDone = 0;
3538         int nToWriteBack;
3539         int startOfWrite = offset;
3540         int chunkWritten = 0;
3541         __u32 n_bytesRead;
3542         __u32 chunkStart;
3543
3544         yaffs_dev_t *dev;
3545
3546         dev = in->my_dev;
3547
3548         while (n > 0 && chunkWritten >= 0) {
3549                 yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3550
3551                 if (chunk * dev->data_bytes_per_chunk + start != offset ||
3552                                 start >= dev->data_bytes_per_chunk) {
3553                         T(YAFFS_TRACE_ERROR, (
3554                            TSTR("AddrToChunk of offset %d gives chunk %d start %d"
3555                            TENDSTR),
3556                            (int)offset, chunk, start));
3557                 }
3558                 chunk++; /* File pos to chunk in file offset */
3559
3560                 /* OK now check for the curveball where the start and end are in
3561                  * the same chunk.
3562                  */
3563
3564                 if ((start + n) < dev->data_bytes_per_chunk) {
3565                         nToCopy = n;
3566
3567                         /* Now folks, to calculate how many bytes to write back....
3568                          * If we're overwriting and not writing to then end of file then
3569                          * we need to write back as much as was there before.
3570                          */
3571
3572                         chunkStart = ((chunk - 1) * dev->data_bytes_per_chunk);
3573
3574                         if (chunkStart > in->variant.file_variant.file_size)
3575                                 n_bytesRead = 0; /* Past end of file */
3576                         else
3577                                 n_bytesRead = in->variant.file_variant.file_size - chunkStart;
3578
3579                         if (n_bytesRead > dev->data_bytes_per_chunk)
3580                                 n_bytesRead = dev->data_bytes_per_chunk;
3581
3582                         nToWriteBack =
3583                             (n_bytesRead >
3584                              (start + n)) ? n_bytesRead : (start + n);
3585
3586                         if (nToWriteBack < 0 || nToWriteBack > dev->data_bytes_per_chunk)
3587                                 YBUG();
3588
3589                 } else {
3590                         nToCopy = dev->data_bytes_per_chunk - start;
3591                         nToWriteBack = dev->data_bytes_per_chunk;
3592                 }
3593
3594                 if (nToCopy != dev->data_bytes_per_chunk || dev->param.inband_tags) {
3595                         /* An incomplete start or end chunk (or maybe both start and end chunk),
3596                          * or we're using inband tags, so we want to use the cache buffers.
3597                          */
3598                         if (dev->param.n_caches > 0) {
3599                                 yaffs_cache_t *cache;
3600                                 /* If we can't find the data in the cache, then load the cache */
3601                                 cache = yaffs_find_chunk_cache(in, chunk);
3602
3603                                 if (!cache
3604                                     && yaffs_check_alloc_available(dev, 1)) {
3605                                         cache = yaffs_grab_chunk_cache(dev);
3606                                         cache->object = in;
3607                                         cache->chunk_id = chunk;
3608                                         cache->dirty = 0;
3609                                         cache->locked = 0;
3610                                         yaffs_rd_data_obj(in, chunk,
3611                                                                       cache->data);
3612                                 } else if (cache &&
3613                                         !cache->dirty &&
3614                                         !yaffs_check_alloc_available(dev, 1)) {
3615                                         /* Drop the cache if it was a read cache item and
3616                                          * no space check has been made for it.
3617                                          */
3618                                          cache = NULL;
3619                                 }
3620
3621                                 if (cache) {
3622                                         yaffs_use_cache(dev, cache, 1);
3623                                         cache->locked = 1;
3624
3625
3626                                         memcpy(&cache->data[start], buffer,
3627                                                nToCopy);
3628
3629
3630                                         cache->locked = 0;
3631                                         cache->n_bytes = nToWriteBack;
3632
3633                                         if (write_trhrough) {
3634                                                 chunkWritten =
3635                                                     yaffs_wr_data_obj
3636                                                     (cache->object,
3637                                                      cache->chunk_id,
3638                                                      cache->data, cache->n_bytes,
3639                                                      1);
3640                                                 cache->dirty = 0;
3641                                         }
3642
3643                                 } else {
3644                                         chunkWritten = -1;      /* fail the write */
3645                                 }
3646                         } else {
3647                                 /* An incomplete start or end chunk (or maybe both start and end chunk)
3648                                  * Read into the local buffer then copy, then copy over and write back.
3649                                  */
3650
3651                                 __u8 *localBuffer =
3652                                     yaffs_get_temp_buffer(dev, __LINE__);
3653
3654                                 yaffs_rd_data_obj(in, chunk,
3655                                                               localBuffer);
3656
3657
3658
3659                                 memcpy(&localBuffer[start], buffer, nToCopy);
3660
3661                                 chunkWritten =
3662                                     yaffs_wr_data_obj(in, chunk,
3663                                                                  localBuffer,
3664                                                                  nToWriteBack,
3665                                                                  0);
3666
3667                                 yaffs_release_temp_buffer(dev, localBuffer,
3668                                                         __LINE__);
3669
3670                         }
3671
3672                 } else {
3673                         /* A full chunk. Write directly from the supplied buffer. */
3674
3675
3676
3677                         chunkWritten =
3678                             yaffs_wr_data_obj(in, chunk, buffer,
3679                                                          dev->data_bytes_per_chunk,
3680                                                          0);
3681
3682                         /* Since we've overwritten the cached data, we better invalidate it. */
3683                         yaffs_invalidate_chunk_cache(in, chunk);
3684                 }
3685
3686                 if (chunkWritten >= 0) {
3687                         n -= nToCopy;
3688                         offset += nToCopy;
3689                         buffer += nToCopy;
3690                         nDone += nToCopy;
3691                 }
3692
3693         }
3694
3695         /* Update file object */
3696
3697         if ((startOfWrite + nDone) > in->variant.file_variant.file_size)
3698                 in->variant.file_variant.file_size = (startOfWrite + nDone);
3699
3700         in->dirty = 1;
3701
3702         return nDone;
3703 }
3704
3705 int yaffs_wr_file(yaffs_obj_t *in, const __u8 *buffer, loff_t offset,
3706                         int n_bytes, int write_trhrough)
3707 {
3708         yaffs2_handle_hole(in,offset);
3709         return yaffs_do_file_wr(in,buffer,offset,n_bytes,write_trhrough);
3710 }
3711
3712
3713
3714 /* ---------------------- File resizing stuff ------------------ */
3715
3716 static void yaffs_prune_chunks(yaffs_obj_t *in, int new_size)
3717 {
3718
3719         yaffs_dev_t *dev = in->my_dev;
3720         int oldFileSize = in->variant.file_variant.file_size;
3721
3722         int lastDel = 1 + (oldFileSize - 1) / dev->data_bytes_per_chunk;
3723
3724         int startDel = 1 + (new_size + dev->data_bytes_per_chunk - 1) /
3725             dev->data_bytes_per_chunk;
3726         int i;
3727         int chunk_id;
3728
3729         /* Delete backwards so that we don't end up with holes if
3730          * power is lost part-way through the operation.
3731          */
3732         for (i = lastDel; i >= startDel; i--) {
3733                 /* NB this could be optimised somewhat,
3734                  * eg. could retrieve the tags and write them without
3735                  * using yaffs_chunk_del
3736                  */
3737
3738                 chunk_id = yaffs_find_del_file_chunk(in, i, NULL);
3739                 if (chunk_id > 0) {
3740                         if (chunk_id <
3741                             (dev->internal_start_block * dev->param.chunks_per_block)
3742                             || chunk_id >=
3743                             ((dev->internal_end_block +
3744                               1) * dev->param.chunks_per_block)) {
3745                                 T(YAFFS_TRACE_ALWAYS,
3746                                   (TSTR("Found daft chunk_id %d for %d" TENDSTR),
3747                                    chunk_id, i));
3748                         } else {
3749                                 in->n_data_chunks--;
3750                                 yaffs_chunk_del(dev, chunk_id, 1, __LINE__);
3751                         }
3752                 }
3753         }
3754
3755 }
3756
3757
3758 void yaffs_resize_file_down( yaffs_obj_t *obj, loff_t new_size)
3759 {
3760         int newFullChunks;
3761         __u32 new_sizeOfPartialChunk;
3762         yaffs_dev_t *dev = obj->my_dev;
3763
3764         yaffs_addr_to_chunk(dev, new_size, &newFullChunks, &new_sizeOfPartialChunk);
3765
3766         yaffs_prune_chunks(obj, new_size);
3767
3768         if (new_sizeOfPartialChunk != 0) {
3769                 int lastChunk = 1 + newFullChunks;
3770                 __u8 *localBuffer = yaffs_get_temp_buffer(dev, __LINE__);
3771
3772                 /* Got to read and rewrite the last chunk with its new size and zero pad */
3773                 yaffs_rd_data_obj(obj, lastChunk, localBuffer);
3774                 memset(localBuffer + new_sizeOfPartialChunk, 0,
3775                         dev->data_bytes_per_chunk - new_sizeOfPartialChunk);
3776
3777                 yaffs_wr_data_obj(obj, lastChunk, localBuffer,
3778                                              new_sizeOfPartialChunk, 1);
3779
3780                 yaffs_release_temp_buffer(dev, localBuffer, __LINE__);
3781         }
3782
3783         obj->variant.file_variant.file_size = new_size;
3784
3785         yaffs_prune_tree(dev, &obj->variant.file_variant);
3786 }
3787
3788
3789 int yaffs_resize_file(yaffs_obj_t *in, loff_t new_size)
3790 {
3791         yaffs_dev_t *dev = in->my_dev;
3792         int oldFileSize = in->variant.file_variant.file_size;
3793
3794         yaffs_flush_file_cache(in);
3795         yaffs_invalidate_whole_cache(in);
3796
3797         yaffs_check_gc(dev,0);
3798
3799         if (in->variant_type != YAFFS_OBJECT_TYPE_FILE)
3800                 return YAFFS_FAIL;
3801
3802         if (new_size == oldFileSize)
3803                 return YAFFS_OK;
3804
3805         if(new_size > oldFileSize){
3806                 yaffs2_handle_hole(in,new_size);
3807                 in->variant.file_variant.file_size = new_size;
3808         } else {
3809                 /* new_size < oldFileSize */
3810                 yaffs_resize_file_down(in, new_size);
3811         }
3812
3813         /* Write a new object header to reflect the resize.
3814          * show we've shrunk the file, if need be
3815          * Do this only if the file is not in the deleted directories
3816          * and is not shadowed.
3817          */
3818         if (in->parent &&
3819             !in->is_shadowed &&
3820             in->parent->obj_id != YAFFS_OBJECTID_UNLINKED &&
3821             in->parent->obj_id != YAFFS_OBJECTID_DELETED)
3822                 yaffs_update_oh(in, NULL, 0, 0, 0, NULL);
3823
3824
3825         return YAFFS_OK;
3826 }
3827
3828 loff_t yaffs_get_file_size(yaffs_obj_t *obj)
3829 {
3830         YCHAR *alias = NULL;
3831         obj = yaffs_get_equivalent_obj(obj);
3832
3833         switch (obj->variant_type) {
3834         case YAFFS_OBJECT_TYPE_FILE:
3835                 return obj->variant.file_variant.file_size;
3836         case YAFFS_OBJECT_TYPE_SYMLINK:
3837                 alias = obj->variant.symlink_variant.alias;
3838                 if(!alias)
3839                         return 0;
3840                 return yaffs_strnlen(alias,YAFFS_MAX_ALIAS_LENGTH);
3841         default:
3842                 return 0;
3843         }
3844 }
3845
3846
3847
3848 int yaffs_flush_file(yaffs_obj_t *in, int update_time, int data_sync)
3849 {
3850         int retVal;
3851         if (in->dirty) {
3852                 yaffs_flush_file_cache(in);
3853                 if(data_sync) /* Only sync data */
3854                         retVal=YAFFS_OK;
3855                 else {
3856                         if (update_time) {
3857 #ifdef CONFIG_YAFFS_WINCE
3858                                 yfsd_win_file_time_now(in->win_mtime);
3859 #else
3860
3861                                 in->yst_mtime = Y_CURRENT_TIME;
3862
3863 #endif
3864                         }
3865
3866                         retVal = (yaffs_update_oh(in, NULL, 0, 0, 0, NULL) >=
3867                                 0) ? YAFFS_OK : YAFFS_FAIL;
3868                 }
3869         } else {
3870                 retVal = YAFFS_OK;
3871         }
3872
3873         return retVal;
3874
3875 }
3876
3877 static int yaffs_generic_obj_del(yaffs_obj_t *in)
3878 {
3879
3880         /* First off, invalidate the file's data in the cache, without flushing. */
3881         yaffs_invalidate_whole_cache(in);
3882
3883         if (in->my_dev->param.is_yaffs2 && (in->parent != in->my_dev->del_dir)) {
3884                 /* Move to the unlinked directory so we have a record that it was deleted. */
3885                 yaffs_change_obj_name(in, in->my_dev->del_dir, _Y("deleted"), 0, 0);
3886
3887         }
3888
3889         yaffs_remove_obj_from_dir(in);
3890         yaffs_chunk_del(in->my_dev, in->hdr_chunk, 1, __LINE__);
3891         in->hdr_chunk = 0;
3892
3893         yaffs_free_obj(in);
3894         return YAFFS_OK;
3895
3896 }
3897
3898 /* yaffs_del_file deletes the whole file data
3899  * and the inode associated with the file.
3900  * It does not delete the links associated with the file.
3901  */
3902 static int yaffs_unlink_file_if_needed(yaffs_obj_t *in)
3903 {
3904
3905         int retVal;
3906         int immediateDeletion = 0;
3907         yaffs_dev_t *dev = in->my_dev;
3908
3909         if (!in->my_inode)
3910                 immediateDeletion = 1;
3911
3912         if (immediateDeletion) {
3913                 retVal =
3914                     yaffs_change_obj_name(in, in->my_dev->del_dir,
3915                                            _Y("deleted"), 0, 0);
3916                 T(YAFFS_TRACE_TRACING,
3917                   (TSTR("yaffs: immediate deletion of file %d" TENDSTR),
3918                    in->obj_id));
3919                 in->deleted = 1;
3920                 in->my_dev->n_deleted_files++;
3921                 if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3922                         yaffs_resize_file(in, 0);
3923                 yaffs_soft_del_file(in);
3924         } else {
3925                 retVal =
3926                     yaffs_change_obj_name(in, in->my_dev->unlinked_dir,
3927                                            _Y("unlinked"), 0, 0);
3928         }
3929
3930
3931         return retVal;
3932 }
3933
3934 int yaffs_del_file(yaffs_obj_t *in)
3935 {
3936         int retVal = YAFFS_OK;
3937         int deleted; /* Need to cache value on stack if in is freed */
3938         yaffs_dev_t *dev = in->my_dev;
3939
3940         if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3941                 yaffs_resize_file(in, 0);
3942
3943         if (in->n_data_chunks > 0) {
3944                 /* Use soft deletion if there is data in the file.
3945                  * That won't be the case if it has been resized to zero.
3946                  */
3947                 if (!in->unlinked)
3948                         retVal = yaffs_unlink_file_if_needed(in);
3949
3950                 deleted = in->deleted;
3951
3952                 if (retVal == YAFFS_OK && in->unlinked && !in->deleted) {
3953                         in->deleted = 1;
3954                         deleted = 1;
3955                         in->my_dev->n_deleted_files++;
3956                         yaffs_soft_del_file(in);
3957                 }
3958                 return deleted ? YAFFS_OK : YAFFS_FAIL;
3959         } else {
3960                 /* The file has no data chunks so we toss it immediately */
3961                 yaffs_free_tnode(in->my_dev, in->variant.file_variant.top);
3962                 in->variant.file_variant.top = NULL;
3963                 yaffs_generic_obj_del(in);
3964
3965                 return YAFFS_OK;
3966         }
3967 }
3968
3969 static int yaffs_is_non_empty_dir(yaffs_obj_t *obj)
3970 {
3971         return (obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) &&
3972                 !(ylist_empty(&obj->variant.dir_variant.children));
3973 }
3974
3975 static int yaffs_del_dir(yaffs_obj_t *obj)
3976 {
3977         /* First check that the directory is empty. */
3978         if (yaffs_is_non_empty_dir(obj))
3979                 return YAFFS_FAIL;
3980
3981         return yaffs_generic_obj_del(obj);
3982 }
3983
3984 static int yaffs_del_symlink(yaffs_obj_t *in)
3985 {
3986         if(in->variant.symlink_variant.alias)
3987                 YFREE(in->variant.symlink_variant.alias);
3988         in->variant.symlink_variant.alias=NULL;
3989
3990         return yaffs_generic_obj_del(in);
3991 }
3992
3993 static int yaffs_del_link(yaffs_obj_t *in)
3994 {
3995         /* remove this hardlink from the list assocaited with the equivalent
3996          * object
3997          */
3998         ylist_del_init(&in->hard_links);
3999         return yaffs_generic_obj_del(in);
4000 }
4001
4002 int yaffs_del_obj(yaffs_obj_t *obj)
4003 {
4004 int retVal = -1;
4005         switch (obj->variant_type) {
4006         case YAFFS_OBJECT_TYPE_FILE:
4007                 retVal = yaffs_del_file(obj);
4008                 break;
4009         case YAFFS_OBJECT_TYPE_DIRECTORY:
4010                 if(!ylist_empty(&obj->variant.dir_variant.dirty)){
4011                         T(YAFFS_TRACE_BACKGROUND, (TSTR("Remove object %d from dirty directories" TENDSTR),obj->obj_id));
4012                         ylist_del_init(&obj->variant.dir_variant.dirty);
4013                 }
4014                 return yaffs_del_dir(obj);
4015                 break;
4016         case YAFFS_OBJECT_TYPE_SYMLINK:
4017                 retVal = yaffs_del_symlink(obj);
4018                 break;
4019         case YAFFS_OBJECT_TYPE_HARDLINK:
4020                 retVal = yaffs_del_link(obj);
4021                 break;
4022         case YAFFS_OBJECT_TYPE_SPECIAL:
4023                 retVal = yaffs_generic_obj_del(obj);
4024                 break;
4025         case YAFFS_OBJECT_TYPE_UNKNOWN:
4026                 retVal = 0;
4027                 break;          /* should not happen. */
4028         }
4029
4030         return retVal;
4031 }
4032
4033 static int yaffs_unlink_worker(yaffs_obj_t *obj)
4034 {
4035
4036         int immediateDeletion = 0;
4037
4038         if (!obj->my_inode)
4039                 immediateDeletion = 1;
4040
4041         if(obj)
4042                 yaffs_update_parent(obj->parent);
4043
4044         if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
4045                 return yaffs_del_link(obj);
4046         } else if (!ylist_empty(&obj->hard_links)) {
4047                 /* Curve ball: We're unlinking an object that has a hardlink.
4048                  *
4049                  * This problem arises because we are not strictly following
4050                  * The Linux link/inode model.
4051                  *
4052                  * We can't really delete the object.
4053                  * Instead, we do the following:
4054                  * - Select a hardlink.
4055                  * - Unhook it from the hard links
4056                  * - Move it from its parent directory (so that the rename can work)
4057                  * - Rename the object to the hardlink's name.
4058                  * - Delete the hardlink
4059                  */
4060
4061                 yaffs_obj_t *hl;
4062                 yaffs_obj_t *parent;
4063                 int retVal;
4064                 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
4065
4066                 hl = ylist_entry(obj->hard_links.next, yaffs_obj_t, hard_links);
4067
4068                 yaffs_get_obj_name(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
4069                 parent = hl->parent;
4070
4071                 ylist_del_init(&hl->hard_links);
4072
4073                 yaffs_add_obj_to_dir(obj->my_dev->unlinked_dir, hl);
4074
4075                 retVal = yaffs_change_obj_name(obj,parent, name, 0, 0);
4076
4077                 if (retVal == YAFFS_OK)
4078                         retVal = yaffs_generic_obj_del(hl);
4079
4080                 return retVal;
4081
4082         } else if (immediateDeletion) {
4083                 switch (obj->variant_type) {
4084                 case YAFFS_OBJECT_TYPE_FILE:
4085                         return yaffs_del_file(obj);
4086                         break;
4087                 case YAFFS_OBJECT_TYPE_DIRECTORY:
4088                         ylist_del_init(&obj->variant.dir_variant.dirty);
4089                         return yaffs_del_dir(obj);
4090                         break;
4091                 case YAFFS_OBJECT_TYPE_SYMLINK:
4092                         return yaffs_del_symlink(obj);
4093                         break;
4094                 case YAFFS_OBJECT_TYPE_SPECIAL:
4095                         return yaffs_generic_obj_del(obj);
4096                         break;
4097                 case YAFFS_OBJECT_TYPE_HARDLINK:
4098                 case YAFFS_OBJECT_TYPE_UNKNOWN:
4099                 default:
4100                         return YAFFS_FAIL;
4101                 }
4102         } else if(yaffs_is_non_empty_dir(obj))
4103                 return YAFFS_FAIL;
4104         else
4105                 return yaffs_change_obj_name(obj, obj->my_dev->unlinked_dir,
4106                                            _Y("unlinked"), 0, 0);
4107 }
4108
4109
4110 static int yaffs_unlink_obj(yaffs_obj_t *obj)
4111 {
4112
4113         if (obj && obj->unlink_allowed)
4114                 return yaffs_unlink_worker(obj);
4115
4116         return YAFFS_FAIL;
4117
4118 }
4119 int yaffs_unlinker(yaffs_obj_t *dir, const YCHAR *name)
4120 {
4121         yaffs_obj_t *obj;
4122
4123         obj = yaffs_find_by_name(dir, name);
4124         return yaffs_unlink_obj(obj);
4125 }
4126
4127 /*----------------------- Initialisation Scanning ---------------------- */
4128
4129 void yaffs_handle_shadowed_obj(yaffs_dev_t *dev, int obj_id,
4130                                 int backward_scanning)
4131 {
4132         yaffs_obj_t *obj;
4133
4134         if (!backward_scanning) {
4135                 /* Handle YAFFS1 forward scanning case
4136                  * For YAFFS1 we always do the deletion
4137                  */
4138
4139         } else {
4140                 /* Handle YAFFS2 case (backward scanning)
4141                  * If the shadowed object exists then ignore.
4142                  */
4143                 obj = yaffs_find_by_number(dev, obj_id);
4144                 if(obj)
4145                         return;
4146         }
4147
4148         /* Let's create it (if it does not exist) assuming it is a file so that it can do shrinking etc.
4149          * We put it in unlinked dir to be cleaned up after the scanning
4150          */
4151         obj =
4152             yaffs_find_or_create_by_number(dev, obj_id,
4153                                              YAFFS_OBJECT_TYPE_FILE);
4154         if (!obj)
4155                 return;
4156         obj->is_shadowed = 1;
4157         yaffs_add_obj_to_dir(dev->unlinked_dir, obj);
4158         obj->variant.file_variant.shrink_size = 0;
4159         obj->valid = 1;         /* So that we don't read any other info for this file */
4160
4161 }
4162
4163
4164 void yaffs_link_fixup(yaffs_dev_t *dev, yaffs_obj_t *hard_list)
4165 {
4166         yaffs_obj_t *hl;
4167         yaffs_obj_t *in;
4168
4169         while (hard_list) {
4170                 hl = hard_list;
4171                 hard_list = (yaffs_obj_t *) (hard_list->hard_links.next);
4172
4173                 in = yaffs_find_by_number(dev,
4174                                               hl->variant.hardlink_variant.
4175                                               equiv_id);
4176
4177                 if (in) {
4178                         /* Add the hardlink pointers */
4179                         hl->variant.hardlink_variant.equiv_obj = in;
4180                         ylist_add(&hl->hard_links, &in->hard_links);
4181                 } else {
4182                         /* Todo Need to report/handle this better.
4183                          * Got a problem... hardlink to a non-existant object
4184                          */
4185                         hl->variant.hardlink_variant.equiv_obj = NULL;
4186                         YINIT_LIST_HEAD(&hl->hard_links);
4187
4188                 }
4189         }
4190 }
4191
4192
4193 static void yaffs_strip_deleted_objs(yaffs_dev_t *dev)
4194 {
4195         /*
4196         *  Sort out state of unlinked and deleted objects after scanning.
4197         */
4198         struct ylist_head *i;
4199         struct ylist_head *n;
4200         yaffs_obj_t *l;
4201
4202         if (dev->read_only)
4203                 return;
4204
4205         /* Soft delete all the unlinked files */
4206         ylist_for_each_safe(i, n,
4207                 &dev->unlinked_dir->variant.dir_variant.children) {
4208                 if (i) {
4209                         l = ylist_entry(i, yaffs_obj_t, siblings);
4210                         yaffs_del_obj(l);
4211                 }
4212         }
4213
4214         ylist_for_each_safe(i, n,
4215                 &dev->del_dir->variant.dir_variant.children) {
4216                 if (i) {
4217                         l = ylist_entry(i, yaffs_obj_t, siblings);
4218                         yaffs_del_obj(l);
4219                 }
4220         }
4221
4222 }
4223
4224 /*
4225  * This code iterates through all the objects making sure that they are rooted.
4226  * Any unrooted objects are re-rooted in lost+found.
4227  * An object needs to be in one of:
4228  * - Directly under deleted, unlinked
4229  * - Directly or indirectly under root.
4230  *
4231  * Note:
4232  *  This code assumes that we don't ever change the current relationships between
4233  *  directories:
4234  *   root_dir->parent == unlinked_dir->parent == del_dir->parent == NULL
4235  *   lostNfound->parent == root_dir
4236  *
4237  * This fixes the problem where directories might have inadvertently been deleted
4238  * leaving the object "hanging" without being rooted in the directory tree.
4239  */
4240
4241 static int yaffs_has_null_parent(yaffs_dev_t *dev, yaffs_obj_t *obj)
4242 {
4243         return (obj == dev->del_dir ||
4244                 obj == dev->unlinked_dir||
4245                 obj == dev->root_dir);
4246 }
4247
4248 static void yaffs_fix_hanging_objs(yaffs_dev_t *dev)
4249 {
4250         yaffs_obj_t *obj;
4251         yaffs_obj_t *parent;
4252         int i;
4253         struct ylist_head *lh;
4254         struct ylist_head *n;
4255         int depthLimit;
4256         int hanging;
4257
4258         if (dev->read_only)
4259                 return;
4260
4261         /* Iterate through the objects in each hash entry,
4262          * looking at each object.
4263          * Make sure it is rooted.
4264          */
4265
4266         for (i = 0; i <  YAFFS_NOBJECT_BUCKETS; i++) {
4267                 ylist_for_each_safe(lh, n, &dev->obj_bucket[i].list) {
4268                         if (lh) {
4269                                 obj = ylist_entry(lh, yaffs_obj_t, hash_link);
4270                                 parent= obj->parent;
4271
4272                                 if(yaffs_has_null_parent(dev,obj)){
4273                                         /* These directories are not hanging */
4274                                         hanging = 0;
4275                                 }
4276                                 else if(!parent || parent->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
4277                                         hanging = 1;
4278                                 else if(yaffs_has_null_parent(dev,parent))
4279                                         hanging = 0;
4280                                 else {
4281                                         /*
4282                                          * Need to follow the parent chain to see if it is hanging.
4283                                          */
4284                                         hanging = 0;
4285                                         depthLimit=100;
4286
4287                                         while(parent != dev->root_dir &&
4288                                                 parent->parent &&
4289                                                 parent->parent->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY &&
4290                                                 depthLimit > 0){
4291                                                 parent = parent->parent;
4292                                                 depthLimit--;
4293                                         }
4294                                         if(parent != dev->root_dir)
4295                                                 hanging = 1;
4296                                 }
4297                                 if(hanging){
4298                                         T(YAFFS_TRACE_SCAN,
4299                                           (TSTR("Hanging object %d moved to lost and found" TENDSTR),
4300                                                 obj->obj_id));
4301                                         yaffs_add_obj_to_dir(dev->lost_n_found,obj);
4302                                 }
4303                         }
4304                 }
4305         }
4306 }
4307
4308
4309 /*
4310  * Delete directory contents for cleaning up lost and found.
4311  */
4312 static void yaffs_del_dir_contents(yaffs_obj_t *dir)
4313 {
4314         yaffs_obj_t *obj;
4315         struct ylist_head *lh;
4316         struct ylist_head *n;
4317
4318         if(dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
4319                 YBUG();
4320
4321         ylist_for_each_safe(lh, n, &dir->variant.dir_variant.children) {
4322                 if (lh) {
4323                         obj = ylist_entry(lh, yaffs_obj_t, siblings);
4324                         if(obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY)
4325                                 yaffs_del_dir_contents(obj);
4326
4327                         T(YAFFS_TRACE_SCAN,
4328                                 (TSTR("Deleting lost_found object %d" TENDSTR),
4329                                 obj->obj_id));
4330
4331                         /* Need to use UnlinkObject since Delete would not handle
4332                          * hardlinked objects correctly.
4333                          */
4334                         yaffs_unlink_obj(obj);
4335                 }
4336         }
4337
4338 }
4339
4340 static void yaffs_empty_l_n_f(yaffs_dev_t *dev)
4341 {
4342         yaffs_del_dir_contents(dev->lost_n_found);
4343 }
4344
4345 static void yaffs_check_obj_details_loaded(yaffs_obj_t *in)
4346 {
4347         __u8 *chunkData;
4348         yaffs_obj_header *oh;
4349         yaffs_dev_t *dev;
4350         yaffs_ext_tags tags;
4351         int result;
4352         int alloc_failed = 0;
4353
4354         if (!in)
4355                 return;
4356
4357         dev = in->my_dev;
4358
4359 #if 0
4360         T(YAFFS_TRACE_SCAN, (TSTR("details for object %d %s loaded" TENDSTR),
4361                 in->obj_id,
4362                 in->lazy_loaded ? "not yet" : "already"));
4363 #endif
4364
4365         if (in->lazy_loaded && in->hdr_chunk > 0) {
4366                 in->lazy_loaded = 0;
4367                 chunkData = yaffs_get_temp_buffer(dev, __LINE__);
4368
4369                 result = yaffs_rd_chunk_tags_nand(dev, in->hdr_chunk, chunkData, &tags);
4370                 oh = (yaffs_obj_header *) chunkData;
4371
4372                 in->yst_mode = oh->yst_mode;
4373 #ifdef CONFIG_YAFFS_WINCE
4374                 in->win_atime[0] = oh->win_atime[0];
4375                 in->win_ctime[0] = oh->win_ctime[0];
4376                 in->win_mtime[0] = oh->win_mtime[0];
4377                 in->win_atime[1] = oh->win_atime[1];
4378                 in->win_ctime[1] = oh->win_ctime[1];
4379                 in->win_mtime[1] = oh->win_mtime[1];
4380 #else
4381                 in->yst_uid = oh->yst_uid;
4382                 in->yst_gid = oh->yst_gid;
4383                 in->yst_atime = oh->yst_atime;
4384                 in->yst_mtime = oh->yst_mtime;
4385                 in->yst_ctime = oh->yst_ctime;
4386                 in->yst_rdev = oh->yst_rdev;
4387
4388 #endif
4389                 yaffs_set_obj_name_from_oh(in, oh);
4390
4391                 if (in->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
4392                         in->variant.symlink_variant.alias =
4393                                                     yaffs_clone_str(oh->alias);
4394                         if (!in->variant.symlink_variant.alias)
4395                                 alloc_failed = 1; /* Not returned to caller */
4396                 }
4397
4398                 yaffs_release_temp_buffer(dev, chunkData, __LINE__);
4399         }
4400 }
4401
4402 /*------------------------------  Directory Functions ----------------------------- */
4403
4404 /*
4405  *yaffs_update_parent() handles fixing a directories mtime and ctime when a new
4406  * link (ie. name) is created or deleted in the directory.
4407  *
4408  * ie.
4409  *   create dir/a : update dir's mtime/ctime
4410  *   rm dir/a:   update dir's mtime/ctime
4411  *   modify dir/a: don't update dir's mtimme/ctime
4412  *
4413  * This can be handled immediately or defered. Defering helps reduce the number
4414  * of updates when many files in a directory are changed within a brief period.
4415  *
4416  * If the directory updating is defered then yaffs_update_dirty_dirs must be
4417  * called periodically.
4418  */
4419
4420 static void yaffs_update_parent(yaffs_obj_t *obj)
4421 {
4422         yaffs_dev_t *dev;
4423         if(!obj)
4424                 return;
4425 #ifndef CONFIG_YAFFS_WINCE
4426
4427         dev = obj->my_dev;
4428         obj->dirty = 1;
4429         obj->yst_mtime = obj->yst_ctime = Y_CURRENT_TIME;
4430         if(dev->param.defered_dir_update){
4431                 struct ylist_head *link = &obj->variant.dir_variant.dirty;
4432
4433                 if(ylist_empty(link)){
4434                         ylist_add(link,&dev->dirty_dirs);
4435                         T(YAFFS_TRACE_BACKGROUND, (TSTR("Added object %d to dirty directories" TENDSTR),obj->obj_id));
4436                 }
4437
4438         } else
4439                 yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
4440 #endif
4441 }
4442
4443 void yaffs_update_dirty_dirs(yaffs_dev_t *dev)
4444 {
4445         struct ylist_head *link;
4446         yaffs_obj_t *obj;
4447         yaffs_dir_s *dS;
4448         yaffs_obj_variant *oV;
4449
4450         T(YAFFS_TRACE_BACKGROUND, (TSTR("Update dirty directories" TENDSTR)));
4451
4452         while(!ylist_empty(&dev->dirty_dirs)){
4453                 link = dev->dirty_dirs.next;
4454                 ylist_del_init(link);
4455
4456                 dS=ylist_entry(link,yaffs_dir_s,dirty);
4457                 oV = ylist_entry(dS,yaffs_obj_variant,dir_variant);
4458                 obj = ylist_entry(oV,yaffs_obj_t,variant);
4459
4460                 T(YAFFS_TRACE_BACKGROUND, (TSTR("Update directory %d" TENDSTR), obj->obj_id));
4461
4462                 if(obj->dirty)
4463                         yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
4464         }
4465 }
4466
4467 static void yaffs_remove_obj_from_dir(yaffs_obj_t *obj)
4468 {
4469         yaffs_dev_t *dev = obj->my_dev;
4470         yaffs_obj_t *parent;
4471
4472         yaffs_verify_obj_in_dir(obj);
4473         parent = obj->parent;
4474
4475         yaffs_verify_dir(parent);
4476
4477         if (dev && dev->param.remove_obj_fn)
4478                 dev->param.remove_obj_fn(obj);
4479
4480
4481         ylist_del_init(&obj->siblings);
4482         obj->parent = NULL;
4483
4484         yaffs_verify_dir(parent);
4485 }
4486
4487 void yaffs_add_obj_to_dir(yaffs_obj_t *directory,
4488                                         yaffs_obj_t *obj)
4489 {
4490         if (!directory) {
4491                 T(YAFFS_TRACE_ALWAYS,
4492                   (TSTR
4493                    ("tragedy: Trying to add an object to a null pointer directory"
4494                     TENDSTR)));
4495                 YBUG();
4496                 return;
4497         }
4498         if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4499                 T(YAFFS_TRACE_ALWAYS,
4500                   (TSTR
4501                    ("tragedy: Trying to add an object to a non-directory"
4502                     TENDSTR)));
4503                 YBUG();
4504         }
4505
4506         if (obj->siblings.prev == NULL) {
4507                 /* Not initialised */
4508                 YBUG();
4509         }
4510
4511
4512         yaffs_verify_dir(directory);
4513
4514         yaffs_remove_obj_from_dir(obj);
4515
4516
4517         /* Now add it */
4518         ylist_add(&obj->siblings, &directory->variant.dir_variant.children);
4519         obj->parent = directory;
4520
4521         if (directory == obj->my_dev->unlinked_dir
4522                         || directory == obj->my_dev->del_dir) {
4523                 obj->unlinked = 1;
4524                 obj->my_dev->n_unlinked_files++;
4525                 obj->rename_allowed = 0;
4526         }
4527
4528         yaffs_verify_dir(directory);
4529         yaffs_verify_obj_in_dir(obj);
4530 }
4531
4532 yaffs_obj_t *yaffs_find_by_name(yaffs_obj_t *directory,
4533                                      const YCHAR *name)
4534 {
4535         int sum;
4536
4537         struct ylist_head *i;
4538         YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
4539
4540         yaffs_obj_t *l;
4541
4542         if (!name)
4543                 return NULL;
4544
4545         if (!directory) {
4546                 T(YAFFS_TRACE_ALWAYS,
4547                   (TSTR
4548                    ("tragedy: yaffs_find_by_name: null pointer directory"
4549                     TENDSTR)));
4550                 YBUG();
4551                 return NULL;
4552         }
4553         if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4554                 T(YAFFS_TRACE_ALWAYS,
4555                   (TSTR
4556                    ("tragedy: yaffs_find_by_name: non-directory" TENDSTR)));
4557                 YBUG();
4558         }
4559
4560         sum = yaffs_calc_name_sum(name);
4561
4562         ylist_for_each(i, &directory->variant.dir_variant.children) {
4563                 if (i) {
4564                         l = ylist_entry(i, yaffs_obj_t, siblings);
4565
4566                         if (l->parent != directory)
4567                                 YBUG();
4568
4569                         yaffs_check_obj_details_loaded(l);
4570
4571                         /* Special case for lost-n-found */
4572                         if (l->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4573                                 if (yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME) == 0)
4574                                         return l;
4575                         } else if (yaffs_sum_cmp(l->sum, sum) || l->hdr_chunk <= 0) {
4576                                 /* LostnFound chunk called Objxxx
4577                                  * Do a real check
4578                                  */
4579                                 yaffs_get_obj_name(l, buffer,
4580                                                     YAFFS_MAX_NAME_LENGTH + 1);
4581                                 if (yaffs_strncmp(name, buffer, YAFFS_MAX_NAME_LENGTH) == 0)
4582                                         return l;
4583                         }
4584                 }
4585         }
4586
4587         return NULL;
4588 }
4589
4590
4591 #if 0
4592 int yaffs_ApplyToDirectoryChildren(yaffs_obj_t *the_dir,
4593                                         int (*fn) (yaffs_obj_t *))
4594 {
4595         struct ylist_head *i;
4596         yaffs_obj_t *l;
4597
4598         if (!the_dir) {
4599                 T(YAFFS_TRACE_ALWAYS,
4600                   (TSTR
4601                    ("tragedy: yaffs_find_by_name: null pointer directory"
4602                     TENDSTR)));
4603                 YBUG();
4604                 return YAFFS_FAIL;
4605         }
4606         if (the_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4607                 T(YAFFS_TRACE_ALWAYS,
4608                   (TSTR
4609                    ("tragedy: yaffs_find_by_name: non-directory" TENDSTR)));
4610                 YBUG();
4611                 return YAFFS_FAIL;
4612         }
4613
4614         ylist_for_each(i, &the_dir->variant.dir_variant.children) {
4615                 if (i) {
4616                         l = ylist_entry(i, yaffs_obj_t, siblings);
4617                         if (l && !fn(l))
4618                                 return YAFFS_FAIL;
4619                 }
4620         }
4621
4622         return YAFFS_OK;
4623
4624 }
4625 #endif
4626
4627 /* GetEquivalentObject dereferences any hard links to get to the
4628  * actual object.
4629  */
4630
4631 yaffs_obj_t *yaffs_get_equivalent_obj(yaffs_obj_t *obj)
4632 {
4633         if (obj && obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
4634                 /* We want the object id of the equivalent object, not this one */
4635                 obj = obj->variant.hardlink_variant.equiv_obj;
4636                 yaffs_check_obj_details_loaded(obj);
4637         }
4638         return obj;
4639 }
4640
4641 /*
4642  *  A note or two on object names.
4643  *  * If the object name is missing, we then make one up in the form objnnn
4644  *
4645  *  * ASCII names are stored in the object header's name field from byte zero
4646  *  * Unicode names are historically stored starting from byte zero.
4647  *
4648  * Then there are automatic Unicode names...
4649  * The purpose of these is to save names in a way that can be read as
4650  * ASCII or Unicode names as appropriate, thus allowing a Unicode and ASCII
4651  * system to share files.
4652  *
4653  * These automatic unicode are stored slightly differently...
4654  *  - If the name can fit in the ASCII character space then they are saved as
4655  *    ascii names as per above.
4656  *  - If the name needs Unicode then the name is saved in Unicode
4657  *    starting at oh->name[1].
4658
4659  */
4660 static void yaffs_fix_null_name(yaffs_obj_t * obj,YCHAR * name, int buffer_size)
4661 {
4662         /* Create an object name if we could not find one. */
4663         if(yaffs_strnlen(name,YAFFS_MAX_NAME_LENGTH) == 0){
4664                 YCHAR locName[20];
4665                 YCHAR numString[20];
4666                 YCHAR *x = &numString[19];
4667                 unsigned v = obj->obj_id;
4668                 numString[19] = 0;
4669                 while(v>0){
4670                         x--;
4671                         *x = '0' + (v % 10);
4672                         v /= 10;
4673                 }
4674                 /* make up a name */
4675                 yaffs_strcpy(locName, YAFFS_LOSTNFOUND_PREFIX);
4676                 yaffs_strcat(locName,x);
4677                 yaffs_strncpy(name, locName, buffer_size - 1);
4678         }
4679 }
4680
4681 static void yaffs_load_name_from_oh(yaffs_dev_t *dev,YCHAR *name, const YCHAR *ohName, int bufferSize)
4682 {
4683 #ifdef CONFIG_YAFFS_AUTO_UNICODE
4684         if(dev->param.auto_unicode){
4685                 if(*ohName){
4686                         /* It is an ASCII name, so do an ASCII to unicode conversion */
4687                         const char *asciiOhName = (const char *)ohName;
4688                         int n = bufferSize - 1;
4689                         while(n > 0 && *asciiOhName){
4690                                 *name = *asciiOhName;
4691                                 name++;
4692                                 asciiOhName++;
4693                                 n--;
4694                         }
4695                 } else
4696                         yaffs_strncpy(name,ohName+1, bufferSize -1);
4697         } else
4698 #endif
4699                 yaffs_strncpy(name, ohName, bufferSize - 1);
4700 }
4701
4702
4703 static void yaffs_load_oh_from_name(yaffs_dev_t *dev, YCHAR *ohName, const YCHAR *name)
4704 {
4705 #ifdef CONFIG_YAFFS_AUTO_UNICODE
4706
4707         int isAscii;
4708         YCHAR *w;
4709
4710         if(dev->param.auto_unicode){
4711
4712                 isAscii = 1;
4713                 w = name;
4714
4715                 /* Figure out if the name will fit in ascii character set */
4716                 while(isAscii && *w){
4717                         if((*w) & 0xff00)
4718                                 isAscii = 0;
4719                         w++;
4720                 }
4721
4722                 if(isAscii){
4723                         /* It is an ASCII name, so do a unicode to ascii conversion */
4724                         char *asciiOhName = (char *)ohName;
4725                         int n = YAFFS_MAX_NAME_LENGTH  - 1;
4726                         while(n > 0 && *name){
4727                                 *asciiOhName= *name;
4728                                 name++;
4729                                 asciiOhName++;
4730                                 n--;
4731                         }
4732                 } else{
4733                         /* It is a unicode name, so save starting at the second YCHAR */
4734                         *ohName = 0;
4735                         yaffs_strncpy(ohName+1,name, YAFFS_MAX_NAME_LENGTH -2);
4736                 }
4737         }
4738         else
4739 #endif
4740                 yaffs_strncpy(ohName,name, YAFFS_MAX_NAME_LENGTH - 1);
4741
4742 }
4743
4744 int yaffs_get_obj_name(yaffs_obj_t * obj, YCHAR * name, int buffer_size)
4745 {
4746         memset(name, 0, buffer_size * sizeof(YCHAR));
4747
4748         yaffs_check_obj_details_loaded(obj);
4749
4750         if (obj->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4751                 yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffer_size - 1);
4752         }
4753 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
4754         else if (obj->short_name[0]) {
4755                 yaffs_strcpy(name, obj->short_name);
4756         }
4757 #endif
4758         else if(obj->hdr_chunk > 0) {
4759                 int result;
4760                 __u8 *buffer = yaffs_get_temp_buffer(obj->my_dev, __LINE__);
4761
4762                 yaffs_obj_header *oh = (yaffs_obj_header *) buffer;
4763
4764                 memset(buffer, 0, obj->my_dev->data_bytes_per_chunk);
4765
4766                 if (obj->hdr_chunk > 0) {
4767                         result = yaffs_rd_chunk_tags_nand(obj->my_dev,
4768                                                         obj->hdr_chunk, buffer,
4769                                                         NULL);
4770                 }
4771                 yaffs_load_name_from_oh(obj->my_dev,name,oh->name,buffer_size);
4772
4773                 yaffs_release_temp_buffer(obj->my_dev, buffer, __LINE__);
4774         }
4775
4776         yaffs_fix_null_name(obj,name,buffer_size);
4777
4778         return yaffs_strnlen(name,YAFFS_MAX_NAME_LENGTH);
4779 }
4780
4781
4782 int yaffs_get_obj_length(yaffs_obj_t *obj)
4783 {
4784         /* Dereference any hard linking */
4785         obj = yaffs_get_equivalent_obj(obj);
4786
4787         if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
4788                 return obj->variant.file_variant.file_size;
4789         if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK){
4790                 if(!obj->variant.symlink_variant.alias)
4791                         return 0;
4792                 return yaffs_strnlen(obj->variant.symlink_variant.alias,YAFFS_MAX_ALIAS_LENGTH);
4793         } else {
4794                 /* Only a directory should drop through to here */
4795                 return obj->my_dev->data_bytes_per_chunk;
4796         }
4797 }
4798
4799 int yaffs_get_obj_link_count(yaffs_obj_t *obj)
4800 {
4801         int count = 0;
4802         struct ylist_head *i;
4803
4804         if (!obj->unlinked)
4805                 count++;                /* the object itself */
4806
4807         ylist_for_each(i, &obj->hard_links)
4808                 count++;                /* add the hard links; */
4809
4810         return count;
4811 }
4812
4813 int yaffs_get_obj_inode(yaffs_obj_t *obj)
4814 {
4815         obj = yaffs_get_equivalent_obj(obj);
4816
4817         return obj->obj_id;
4818 }
4819
4820 unsigned yaffs_get_obj_type(yaffs_obj_t *obj)
4821 {
4822         obj = yaffs_get_equivalent_obj(obj);
4823
4824         switch (obj->variant_type) {
4825         case YAFFS_OBJECT_TYPE_FILE:
4826                 return DT_REG;
4827                 break;
4828         case YAFFS_OBJECT_TYPE_DIRECTORY:
4829                 return DT_DIR;
4830                 break;
4831         case YAFFS_OBJECT_TYPE_SYMLINK:
4832                 return DT_LNK;
4833                 break;
4834         case YAFFS_OBJECT_TYPE_HARDLINK:
4835                 return DT_REG;
4836                 break;
4837         case YAFFS_OBJECT_TYPE_SPECIAL:
4838                 if (S_ISFIFO(obj->yst_mode))
4839                         return DT_FIFO;
4840                 if (S_ISCHR(obj->yst_mode))
4841                         return DT_CHR;
4842                 if (S_ISBLK(obj->yst_mode))
4843                         return DT_BLK;
4844                 if (S_ISSOCK(obj->yst_mode))
4845                         return DT_SOCK;
4846         default:
4847                 return DT_REG;
4848                 break;
4849         }
4850 }
4851
4852 YCHAR *yaffs_get_symlink_alias(yaffs_obj_t *obj)
4853 {
4854         obj = yaffs_get_equivalent_obj(obj);
4855         if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK)
4856                 return yaffs_clone_str(obj->variant.symlink_variant.alias);
4857         else
4858                 return yaffs_clone_str(_Y(""));
4859 }
4860
4861 #ifndef CONFIG_YAFFS_WINCE
4862
4863 int yaffs_set_attribs(yaffs_obj_t *obj, struct iattr *attr)
4864 {
4865         unsigned int valid = attr->ia_valid;
4866
4867         if (valid & ATTR_MODE)
4868                 obj->yst_mode = attr->ia_mode;
4869         if (valid & ATTR_UID)
4870                 obj->yst_uid = attr->ia_uid;
4871         if (valid & ATTR_GID)
4872                 obj->yst_gid = attr->ia_gid;
4873
4874         if (valid & ATTR_ATIME)
4875                 obj->yst_atime = Y_TIME_CONVERT(attr->ia_atime);
4876         if (valid & ATTR_CTIME)
4877                 obj->yst_ctime = Y_TIME_CONVERT(attr->ia_ctime);
4878         if (valid & ATTR_MTIME)
4879                 obj->yst_mtime = Y_TIME_CONVERT(attr->ia_mtime);
4880
4881         if (valid & ATTR_SIZE)
4882                 yaffs_resize_file(obj, attr->ia_size);
4883
4884         yaffs_update_oh(obj, NULL, 1, 0, 0, NULL);
4885
4886         return YAFFS_OK;
4887
4888 }
4889 int yaffs_get_attribs(yaffs_obj_t *obj, struct iattr *attr)
4890 {
4891         unsigned int valid = 0;
4892
4893         attr->ia_mode = obj->yst_mode;
4894         valid |= ATTR_MODE;
4895         attr->ia_uid = obj->yst_uid;
4896         valid |= ATTR_UID;
4897         attr->ia_gid = obj->yst_gid;
4898         valid |= ATTR_GID;
4899
4900         Y_TIME_CONVERT(attr->ia_atime) = obj->yst_atime;
4901         valid |= ATTR_ATIME;
4902         Y_TIME_CONVERT(attr->ia_ctime) = obj->yst_ctime;
4903         valid |= ATTR_CTIME;
4904         Y_TIME_CONVERT(attr->ia_mtime) = obj->yst_mtime;
4905         valid |= ATTR_MTIME;
4906
4907         attr->ia_size = yaffs_get_file_size(obj);
4908         valid |= ATTR_SIZE;
4909
4910         attr->ia_valid = valid;
4911
4912         return YAFFS_OK;
4913 }
4914
4915 #endif
4916
4917
4918 static int yaffs_do_xattrib_mod(yaffs_obj_t *obj, int set, const YCHAR *name, const void *value, int size, int flags)
4919 {
4920         yaffs_xattr_mod xmod;
4921
4922         int result;
4923
4924         xmod.set = set;
4925         xmod.name = name;
4926         xmod.data = value;
4927         xmod.size =  size;
4928         xmod.flags = flags;
4929         xmod.result = -ENOSPC;
4930
4931         result = yaffs_update_oh(obj, NULL, 0, 0, 0, &xmod);
4932
4933         if(result > 0)
4934                 return xmod.result;
4935         else
4936                 return -ENOSPC;
4937 }
4938
4939 static int yaffs_apply_xattrib_mod(yaffs_obj_t *obj, char *buffer, yaffs_xattr_mod *xmod)
4940 {
4941         int retval = 0;
4942         int x_offs = sizeof(yaffs_obj_header);
4943         yaffs_dev_t *dev = obj->my_dev;
4944         int x_size = dev->data_bytes_per_chunk - sizeof(yaffs_obj_header);
4945
4946         char * x_buffer = buffer + x_offs;
4947
4948         if(xmod->set)
4949                 retval = nval_set(x_buffer, x_size, xmod->name, xmod->data, xmod->size, xmod->flags);
4950         else
4951                 retval = nval_del(x_buffer, x_size, xmod->name);
4952
4953         obj->has_xattr = nval_hasvalues(x_buffer, x_size);
4954         obj->xattr_known = 1;
4955
4956         xmod->result = retval;
4957
4958         return retval;
4959 }
4960
4961 static int yaffs_do_xattrib_fetch(yaffs_obj_t *obj, const YCHAR *name, void *value, int size)
4962 {
4963         char *buffer = NULL;
4964         int result;
4965         yaffs_ext_tags tags;
4966         yaffs_dev_t *dev = obj->my_dev;
4967         int x_offs = sizeof(yaffs_obj_header);
4968         int x_size = dev->data_bytes_per_chunk - sizeof(yaffs_obj_header);
4969
4970         char * x_buffer;
4971
4972         int retval = 0;
4973
4974         if(obj->hdr_chunk < 1)
4975                 return -ENODATA;
4976
4977         /* If we know that the object has no xattribs then don't do all the
4978          * reading and parsing.
4979          */
4980         if(obj->xattr_known && !obj->has_xattr){
4981                 if(name)
4982                         return -ENODATA;
4983                 else
4984                         return 0;
4985         }
4986
4987         buffer = (char *) yaffs_get_temp_buffer(dev, __LINE__);
4988         if(!buffer)
4989                 return -ENOMEM;
4990
4991         result = yaffs_rd_chunk_tags_nand(dev,obj->hdr_chunk, (__u8 *)buffer, &tags);
4992
4993         if(result != YAFFS_OK)
4994                 retval = -ENOENT;
4995         else{
4996                 x_buffer =  buffer + x_offs;
4997
4998                 if (!obj->xattr_known){
4999                         obj->has_xattr = nval_hasvalues(x_buffer, x_size);
5000                         obj->xattr_known = 1;
5001                 }
5002
5003                 if(name)
5004                         retval = nval_get(x_buffer, x_size, name, value, size);
5005                 else
5006                         retval = nval_list(x_buffer, x_size, value,size);
5007         }
5008         yaffs_release_temp_buffer(dev,(__u8 *)buffer,__LINE__);
5009         return retval;
5010 }
5011
5012 int yaffs_set_xattrib(yaffs_obj_t *obj, const YCHAR *name, const void * value, int size, int flags)
5013 {
5014         return yaffs_do_xattrib_mod(obj, 1, name, value, size, flags);
5015 }
5016
5017 int yaffs_remove_xattrib(yaffs_obj_t *obj, const YCHAR *name)
5018 {
5019         return yaffs_do_xattrib_mod(obj, 0, name, NULL, 0, 0);
5020 }
5021
5022 int yaffs_get_xattrib(yaffs_obj_t *obj, const YCHAR *name, void *value, int size)
5023 {
5024         return yaffs_do_xattrib_fetch(obj, name, value, size);
5025 }
5026
5027 int yaffs_list_xattrib(yaffs_obj_t *obj, char *buffer, int size)
5028 {
5029         return yaffs_do_xattrib_fetch(obj, NULL, buffer,size);
5030 }
5031
5032
5033
5034 #if 0
5035 int yaffs_dump_obj(yaffs_obj_t *obj)
5036 {
5037         YCHAR name[257];
5038
5039         yaffs_get_obj_name(obj, name, YAFFS_MAX_NAME_LENGTH + 1);
5040
5041         T(YAFFS_TRACE_ALWAYS,
5042           (TSTR
5043            ("Object %d, inode %d \"%s\"\n dirty %d valid %d serial %d sum %d"
5044             " chunk %d type %d size %d\n"
5045             TENDSTR), obj->obj_id, yaffs_get_obj_inode(obj), name,
5046            obj->dirty, obj->valid, obj->serial, obj->sum, obj->hdr_chunk,
5047            yaffs_get_obj_type(obj), yaffs_get_obj_length(obj)));
5048
5049         return YAFFS_OK;
5050 }
5051 #endif
5052
5053 /*---------------------------- Initialisation code -------------------------------------- */
5054
5055 static int yaffs_cehck_dev_fns(const yaffs_dev_t *dev)
5056 {
5057
5058         /* Common functions, gotta have */
5059         if (!dev->param.erase_fn || !dev->param.initialise_flash_fn)
5060                 return 0;
5061
5062 #ifdef CONFIG_YAFFS_YAFFS2
5063
5064         /* Can use the "with tags" style interface for yaffs1 or yaffs2 */
5065         if (dev->param.write_chunk_tags_fn &&
5066             dev->param.read_chunk_tags_fn &&
5067             !dev->param.write_chunk_fn &&
5068             !dev->param.read_chunk_fn &&
5069             dev->param.bad_block_fn &&
5070             dev->param.query_block_fn)
5071                 return 1;
5072 #endif
5073
5074         /* Can use the "spare" style interface for yaffs1 */
5075         if (!dev->param.is_yaffs2 &&
5076             !dev->param.write_chunk_tags_fn &&
5077             !dev->param.read_chunk_tags_fn &&
5078             dev->param.write_chunk_fn &&
5079             dev->param.read_chunk_fn &&
5080             !dev->param.bad_block_fn &&
5081             !dev->param.query_block_fn)
5082                 return 1;
5083
5084         return 0;       /* bad */
5085 }
5086
5087
5088 static int yaffs_create_initial_dir(yaffs_dev_t *dev)
5089 {
5090         /* Initialise the unlinked, deleted, root and lost and found directories */
5091
5092         dev->lost_n_found = dev->root_dir =  NULL;
5093         dev->unlinked_dir = dev->del_dir = NULL;
5094
5095         dev->unlinked_dir =
5096             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
5097
5098         dev->del_dir =
5099             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
5100
5101         dev->root_dir =
5102             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_ROOT,
5103                                       YAFFS_ROOT_MODE | S_IFDIR);
5104         dev->lost_n_found =
5105             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_LOSTNFOUND,
5106                                       YAFFS_LOSTNFOUND_MODE | S_IFDIR);
5107
5108         if (dev->lost_n_found && dev->root_dir && dev->unlinked_dir && dev->del_dir) {
5109                 yaffs_add_obj_to_dir(dev->root_dir, dev->lost_n_found);
5110                 return YAFFS_OK;
5111         }
5112
5113         return YAFFS_FAIL;
5114 }
5115
5116 int yaffs_guts_initialise(yaffs_dev_t *dev)
5117 {
5118         int init_failed = 0;
5119         unsigned x;
5120         int bits;
5121
5122         T(YAFFS_TRACE_TRACING, (TSTR("yaffs: yaffs_guts_initialise()" TENDSTR)));
5123
5124         /* Check stuff that must be set */
5125
5126         if (!dev) {
5127                 T(YAFFS_TRACE_ALWAYS, (TSTR("yaffs: Need a device" TENDSTR)));
5128                 return YAFFS_FAIL;
5129         }
5130
5131         dev->internal_start_block = dev->param.start_block;
5132         dev->internal_end_block = dev->param.end_block;
5133         dev->block_offset = 0;
5134         dev->chunk_offset = 0;
5135         dev->n_free_chunks = 0;
5136
5137         dev->gc_block = 0;
5138
5139         if (dev->param.start_block == 0) {
5140                 dev->internal_start_block = dev->param.start_block + 1;
5141                 dev->internal_end_block = dev->param.end_block + 1;
5142                 dev->block_offset = 1;
5143                 dev->chunk_offset = dev->param.chunks_per_block;
5144         }
5145
5146         /* Check geometry parameters. */
5147
5148         if ((!dev->param.inband_tags && dev->param.is_yaffs2 && dev->param.total_bytes_per_chunk < 1024) ||
5149             (!dev->param.is_yaffs2 && dev->param.total_bytes_per_chunk < 512) ||
5150             (dev->param.inband_tags && !dev->param.is_yaffs2) ||
5151              dev->param.chunks_per_block < 2 ||
5152              dev->param.n_reserved_blocks < 2 ||
5153              dev->internal_start_block <= 0 ||
5154              dev->internal_end_block <= 0 ||
5155              dev->internal_end_block <= (dev->internal_start_block + dev->param.n_reserved_blocks + 2)) {       /* otherwise it is too small */
5156                 T(YAFFS_TRACE_ALWAYS,
5157                   (TSTR
5158                    ("yaffs: NAND geometry problems: chunk size %d, type is yaffs%s, inband_tags %d "
5159                     TENDSTR), dev->param.total_bytes_per_chunk, dev->param.is_yaffs2 ? "2" : "", dev->param.inband_tags));
5160                 return YAFFS_FAIL;
5161         }
5162
5163         if (yaffs_init_nand(dev) != YAFFS_OK) {
5164                 T(YAFFS_TRACE_ALWAYS,
5165                   (TSTR("yaffs: InitialiseNAND failed" TENDSTR)));
5166                 return YAFFS_FAIL;
5167         }
5168
5169         /* Sort out space for inband tags, if required */
5170         if (dev->param.inband_tags)
5171                 dev->data_bytes_per_chunk = dev->param.total_bytes_per_chunk - sizeof(yaffs_PackedTags2TagsPart);
5172         else
5173                 dev->data_bytes_per_chunk = dev->param.total_bytes_per_chunk;
5174
5175         /* Got the right mix of functions? */
5176         if (!yaffs_cehck_dev_fns(dev)) {
5177                 /* Function missing */
5178                 T(YAFFS_TRACE_ALWAYS,
5179                   (TSTR
5180                    ("yaffs: device function(s) missing or wrong\n" TENDSTR)));
5181
5182                 return YAFFS_FAIL;
5183         }
5184
5185         /* This is really a compilation check. */
5186         if (!yaffs_check_structures()) {
5187                 T(YAFFS_TRACE_ALWAYS,
5188                   (TSTR("yaffs_check_structures failed\n" TENDSTR)));
5189                 return YAFFS_FAIL;
5190         }
5191
5192         if (dev->is_mounted) {
5193                 T(YAFFS_TRACE_ALWAYS,
5194                   (TSTR("yaffs: device already mounted\n" TENDSTR)));
5195                 return YAFFS_FAIL;
5196         }
5197
5198         /* Finished with most checks. One or two more checks happen later on too. */
5199
5200         dev->is_mounted = 1;
5201
5202         /* OK now calculate a few things for the device */
5203
5204         /*
5205          *  Calculate all the chunk size manipulation numbers:
5206          */
5207         x = dev->data_bytes_per_chunk;
5208         /* We always use dev->chunk_shift and dev->chunk_div */
5209         dev->chunk_shift = Shifts(x);
5210         x >>= dev->chunk_shift;
5211         dev->chunk_div = x;
5212         /* We only use chunk mask if chunk_div is 1 */
5213         dev->chunk_mask = (1<<dev->chunk_shift) - 1;
5214
5215         /*
5216          * Calculate chunk_grp_bits.
5217          * We need to find the next power of 2 > than internal_end_block
5218          */
5219
5220         x = dev->param.chunks_per_block * (dev->internal_end_block + 1);
5221
5222         bits = ShiftsGE(x);
5223
5224         /* Set up tnode width if wide tnodes are enabled. */
5225         if (!dev->param.wide_tnodes_disabled) {
5226                 /* bits must be even so that we end up with 32-bit words */
5227                 if (bits & 1)
5228                         bits++;
5229                 if (bits < 16)
5230                         dev->tnode_width = 16;
5231                 else
5232                         dev->tnode_width = bits;
5233         } else
5234                 dev->tnode_width = 16;
5235
5236         dev->tnode_mask = (1<<dev->tnode_width)-1;
5237
5238         /* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
5239          * so if the bitwidth of the
5240          * chunk range we're using is greater than 16 we need
5241          * to figure out chunk shift and chunk_grp_size
5242          */
5243
5244         if (bits <= dev->tnode_width)
5245                 dev->chunk_grp_bits = 0;
5246         else
5247                 dev->chunk_grp_bits = bits - dev->tnode_width;
5248
5249         dev->tnode_size = (dev->tnode_width * YAFFS_NTNODES_LEVEL0)/8;
5250         if(dev->tnode_size < sizeof(yaffs_tnode_t))
5251                 dev->tnode_size = sizeof(yaffs_tnode_t);
5252
5253         dev->chunk_grp_size = 1 << dev->chunk_grp_bits;
5254
5255         if (dev->param.chunks_per_block < dev->chunk_grp_size) {
5256                 /* We have a problem because the soft delete won't work if
5257                  * the chunk group size > chunks per block.
5258                  * This can be remedied by using larger "virtual blocks".
5259                  */
5260                 T(YAFFS_TRACE_ALWAYS,
5261                   (TSTR("yaffs: chunk group too large\n" TENDSTR)));
5262
5263                 return YAFFS_FAIL;
5264         }
5265
5266         /* OK, we've finished verifying the device, lets continue with initialisation */
5267
5268         /* More device initialisation */
5269         dev->all_gcs = 0;
5270         dev->passive_gc_count = 0;
5271         dev->oldest_dirty_gc_count = 0;
5272         dev->bg_gcs = 0;
5273         dev->gc_block_finder = 0;
5274         dev->buffered_block = -1;
5275         dev->doing_buffered_block_rewrite = 0;
5276         dev->n_deleted_files = 0;
5277         dev->n_bg_deletions = 0;
5278         dev->n_unlinked_files = 0;
5279         dev->n_ecc_fixed = 0;
5280         dev->n_ecc_unfixed = 0;
5281         dev->n_tags_ecc_fixed = 0;
5282         dev->n_tags_ecc_unfixed = 0;
5283         dev->n_erase_failures = 0;
5284         dev->n_erased_blocks = 0;
5285         dev->gc_disable= 0;
5286         dev->has_pending_prioritised_gc = 1; /* Assume the worst for now, will get fixed on first GC */
5287         YINIT_LIST_HEAD(&dev->dirty_dirs);
5288         dev->oldest_dirty_seq = 0;
5289         dev->oldest_dirty_block = 0;
5290
5291         /* Initialise temporary buffers and caches. */
5292         if (!yaffs_init_tmp_buffers(dev))
5293                 init_failed = 1;
5294
5295         dev->cache = NULL;
5296         dev->gc_cleanup_list = NULL;
5297
5298
5299         if (!init_failed &&
5300             dev->param.n_caches > 0) {
5301                 int i;
5302                 void *buf;
5303                 int cacheBytes = dev->param.n_caches * sizeof(yaffs_cache_t);
5304
5305                 if (dev->param.n_caches > YAFFS_MAX_SHORT_OP_CACHES)
5306                         dev->param.n_caches = YAFFS_MAX_SHORT_OP_CACHES;
5307
5308                 dev->cache =  YMALLOC(cacheBytes);
5309
5310                 buf = (__u8 *) dev->cache;
5311
5312                 if (dev->cache)
5313                         memset(dev->cache, 0, cacheBytes);
5314
5315                 for (i = 0; i < dev->param.n_caches && buf; i++) {
5316                         dev->cache[i].object = NULL;
5317                         dev->cache[i].last_use = 0;
5318                         dev->cache[i].dirty = 0;
5319                         dev->cache[i].data = buf = YMALLOC_DMA(dev->param.total_bytes_per_chunk);
5320                 }
5321                 if (!buf)
5322                         init_failed = 1;
5323
5324                 dev->cache_last_use = 0;
5325         }
5326
5327         dev->cache_hits = 0;
5328
5329         if (!init_failed) {
5330                 dev->gc_cleanup_list = YMALLOC(dev->param.chunks_per_block * sizeof(__u32));
5331                 if (!dev->gc_cleanup_list)
5332                         init_failed = 1;
5333         }
5334
5335         if (dev->param.is_yaffs2)
5336                 dev->param.use_header_file_size = 1;
5337
5338         if (!init_failed && !yaffs_init_blocks(dev))
5339                 init_failed = 1;
5340
5341         yaffs_init_tnodes_and_objs(dev);
5342
5343         if (!init_failed && !yaffs_create_initial_dir(dev))
5344                 init_failed = 1;
5345
5346
5347         if (!init_failed) {
5348                 /* Now scan the flash. */
5349                 if (dev->param.is_yaffs2) {
5350                         if (yaffs2_checkpt_restore(dev)) {
5351                                 yaffs_check_obj_details_loaded(dev->root_dir);
5352                                 T(YAFFS_TRACE_ALWAYS,
5353                                   (TSTR("yaffs: restored from checkpoint" TENDSTR)));
5354                         } else {
5355
5356                                 /* Clean up the mess caused by an aborted checkpoint load
5357                                  * and scan backwards.
5358                                  */
5359                                 yaffs_deinit_blocks(dev);
5360
5361                                 yaffs_deinit_tnodes_and_objs(dev);
5362
5363                                 dev->n_erased_blocks = 0;
5364                                 dev->n_free_chunks = 0;
5365                                 dev->alloc_block = -1;
5366                                 dev->alloc_page = -1;
5367                                 dev->n_deleted_files = 0;
5368                                 dev->n_unlinked_files = 0;
5369                                 dev->n_bg_deletions = 0;
5370
5371                                 if (!init_failed && !yaffs_init_blocks(dev))
5372                                         init_failed = 1;
5373
5374                                 yaffs_init_tnodes_and_objs(dev);
5375
5376                                 if (!init_failed && !yaffs_create_initial_dir(dev))
5377                                         init_failed = 1;
5378
5379                                 if (!init_failed && !yaffs2_scan_backwards(dev))
5380                                         init_failed = 1;
5381                         }
5382                 } else if (!yaffs1_scan(dev))
5383                                 init_failed = 1;
5384
5385                 yaffs_strip_deleted_objs(dev);
5386                 yaffs_fix_hanging_objs(dev);
5387                 if(dev->param.empty_lost_n_found)
5388                         yaffs_empty_l_n_f(dev);
5389         }
5390
5391         if (init_failed) {
5392                 /* Clean up the mess */
5393                 T(YAFFS_TRACE_TRACING,
5394                   (TSTR("yaffs: yaffs_guts_initialise() aborted.\n" TENDSTR)));
5395
5396                 yaffs_deinitialise(dev);
5397                 return YAFFS_FAIL;
5398         }
5399
5400         /* Zero out stats */
5401         dev->n_page_reads = 0;
5402         dev->n_page_writes = 0;
5403         dev->n_erasures = 0;
5404         dev->n_gc_copies = 0;
5405         dev->n_retired_writes = 0;
5406
5407         dev->n_retired_blocks = 0;
5408
5409         yaffs_verify_free_chunks(dev);
5410         yaffs_verify_blocks(dev);
5411
5412         /* Clean up any aborted checkpoint data */
5413         if(!dev->is_checkpointed && dev->blocks_in_checkpt > 0)
5414                 yaffs2_checkpt_invalidate(dev);
5415
5416         T(YAFFS_TRACE_TRACING,
5417           (TSTR("yaffs: yaffs_guts_initialise() done.\n" TENDSTR)));
5418         return YAFFS_OK;
5419
5420 }
5421
5422 void yaffs_deinitialise(yaffs_dev_t *dev)
5423 {
5424         if (dev->is_mounted) {
5425                 int i;
5426
5427                 yaffs_deinit_blocks(dev);
5428                 yaffs_deinit_tnodes_and_objs(dev);
5429                 if (dev->param.n_caches > 0 &&
5430                     dev->cache) {
5431
5432                         for (i = 0; i < dev->param.n_caches; i++) {
5433                                 if (dev->cache[i].data)
5434                                         YFREE(dev->cache[i].data);
5435                                 dev->cache[i].data = NULL;
5436                         }
5437
5438                         YFREE(dev->cache);
5439                         dev->cache = NULL;
5440                 }
5441
5442                 YFREE(dev->gc_cleanup_list);
5443
5444                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
5445                         YFREE(dev->temp_buffer[i].buffer);
5446
5447                 dev->is_mounted = 0;
5448
5449                 if (dev->param.deinitialise_flash_fn)
5450                         dev->param.deinitialise_flash_fn(dev);
5451         }
5452 }
5453
5454 int yaffs_count_free_chunks(yaffs_dev_t *dev)
5455 {
5456         int nFree=0;
5457         int b;
5458
5459         yaffs_block_info_t *blk;
5460
5461         blk = dev->block_info;
5462         for (b = dev->internal_start_block; b <= dev->internal_end_block; b++) {
5463                 switch (blk->block_state) {
5464                 case YAFFS_BLOCK_STATE_EMPTY:
5465                 case YAFFS_BLOCK_STATE_ALLOCATING:
5466                 case YAFFS_BLOCK_STATE_COLLECTING:
5467                 case YAFFS_BLOCK_STATE_FULL:
5468                         nFree +=
5469                             (dev->param.chunks_per_block - blk->pages_in_use +
5470                              blk->soft_del_pages);
5471                         break;
5472                 default:
5473                         break;
5474                 }
5475                 blk++;
5476         }
5477
5478         return nFree;
5479 }
5480
5481 int yaffs_get_n_free_chunks(yaffs_dev_t *dev)
5482 {
5483         /* This is what we report to the outside world */
5484
5485         int nFree;
5486         int nDirtyCacheChunks;
5487         int blocksForCheckpoint;
5488         int i;
5489
5490 #if 1
5491         nFree = dev->n_free_chunks;
5492 #else
5493         nFree = yaffs_count_free_chunks(dev);
5494 #endif
5495
5496         nFree += dev->n_deleted_files;
5497
5498         /* Now count the number of dirty chunks in the cache and subtract those */
5499
5500         for (nDirtyCacheChunks = 0, i = 0; i < dev->param.n_caches; i++) {
5501                 if (dev->cache[i].dirty)
5502                         nDirtyCacheChunks++;
5503         }
5504
5505         nFree -= nDirtyCacheChunks;
5506
5507         nFree -= ((dev->param.n_reserved_blocks + 1) * dev->param.chunks_per_block);
5508
5509         /* Now we figure out how much to reserve for the checkpoint and report that... */
5510         blocksForCheckpoint = yaffs_calc_checkpt_blocks_required(dev);
5511
5512         nFree -= (blocksForCheckpoint * dev->param.chunks_per_block);
5513
5514         if (nFree < 0)
5515                 nFree = 0;
5516
5517         return nFree;
5518
5519 }
5520
5521
5522 /*---------------------------------------- YAFFS test code ----------------------*/
5523
5524 #define yaffs_check_struct(structure, syze, name) \
5525         do { \
5526                 if (sizeof(structure) != syze) { \
5527                         T(YAFFS_TRACE_ALWAYS, (TSTR("%s should be %d but is %d\n" TENDSTR),\
5528                                 name, syze, (int) sizeof(structure))); \
5529                         return YAFFS_FAIL; \
5530                 } \
5531         } while (0)
5532
5533 static int yaffs_check_structures(void)
5534 {
5535 /*      yaffs_check_struct(yaffs_tags_t,8,"yaffs_tags_t"); */
5536 /*      yaffs_check_struct(yaffs_tags_union_t,8,"yaffs_tags_union_t"); */
5537 /*      yaffs_check_struct(yaffs_spare,16,"yaffs_spare"); */
5538 /*      yaffs_check_struct(yaffs_tnode_t, 2 * YAFFS_NTNODES_LEVEL0, "yaffs_tnode_t"); */
5539
5540 #ifndef CONFIG_YAFFS_WINCE
5541         yaffs_check_struct(yaffs_obj_header, 512, "yaffs_obj_header");
5542 #endif
5543         return YAFFS_OK;
5544 }