flight/pios/common/libraries/yaffs2/yaffs_guts.c

   1 /*
   2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2011 Aleph One Ltd.
   5  *   for Toby Churchill Ltd and Brightstar Engineering
   6  *
   7  * Created by Charles Manning <charles@aleph1.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include "yportenv.h"
  15 #include "yaffs_trace.h"
  16
  17 #include "yaffs_guts.h"
  18 #include "yaffs_getblockinfo.h"
  19 #include "yaffs_tagscompat.h"
  20 #include "yaffs_tagsmarshall.h"
  21 #include "yaffs_nand.h"
  22 #include "yaffs_yaffs1.h"
  23 #include "yaffs_yaffs2.h"
  24 #include "yaffs_bitmap.h"
  25 #include "yaffs_verify.h"
  26 #include "yaffs_nand.h"
  27 #include "yaffs_packedtags2.h"
  28 #include "yaffs_nameval.h"
  29 #include "yaffs_allocator.h"
  30 #include "yaffs_attribs.h"
  31 #include "yaffs_summary.h"
  32
  33 /* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
  34 #define YAFFS_GC_GOOD_ENOUGH 2
  35 #define YAFFS_GC_PASSIVE_THRESHOLD 4
  36
  37 #include "yaffs_ecc.h"
  38
  39 /* Forward declarations */
  40
  41 static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
  42                              const u8 *buffer, int n_bytes, int use_reserve);
  43
  44 static void yaffs_fix_null_name(struct yaffs_obj *obj, YCHAR *name,
  45                                 int buffer_size);
  46
  47 /* Function to calculate chunk and offset */
  48
  49 void yaffs_addr_to_chunk(struct yaffs_dev *dev, Y_LOFF_T addr,
  50                                 int *chunk_out, u32 *offset_out)
  51 {
  52         int chunk;
  53         u32 offset;
  54
  55         chunk = (u32) (addr >> dev->chunk_shift);
  56
  57         if (dev->chunk_div == 1) {
  58                 /* easy power of 2 case */
  59                 offset = (u32) (addr & dev->chunk_mask);
  60         } else {
  61                 /* Non power-of-2 case */
  62
  63                 Y_LOFF_T chunk_base;
  64
  65                 chunk /= dev->chunk_div;
  66
  67                 chunk_base = ((Y_LOFF_T) chunk) * dev->data_bytes_per_chunk;
  68                 offset = (u32) (addr - chunk_base);
  69         }
  70
  71         *chunk_out = chunk;
  72         *offset_out = offset;
  73 }
  74
  75 /* Function to return the number of shifts for a power of 2 greater than or
  76  * equal to the given number
  77  * Note we don't try to cater for all possible numbers and this does not have to
  78  * be hellishly efficient.
  79  */
  80
  81 static inline u32 calc_shifts_ceiling(u32 x)
  82 {
  83         int extra_bits;
  84         int shifts;
  85
  86         shifts = extra_bits = 0;
  87
  88         while (x > 1) {
  89                 if (x & 1)
  90                         extra_bits++;
  91                 x >>= 1;
  92                 shifts++;
  93         }
  94
  95         if (extra_bits)
  96                 shifts++;
  97
  98         return shifts;
  99 }
 100
 101 /* Function to return the number of shifts to get a 1 in bit 0
 102  */
 103
 104 static inline u32 calc_shifts(u32 x)
 105 {
 106         u32 shifts;
 107
 108         shifts = 0;
 109
 110         if (!x)
 111                 return 0;
 112
 113         while (!(x & 1)) {
 114                 x >>= 1;
 115                 shifts++;
 116         }
 117
 118         return shifts;
 119 }
 120
 121 /*
 122  * Temporary buffer manipulations.
 123  */
 124
 125 static int yaffs_init_tmp_buffers(struct yaffs_dev *dev)
 126 {
 127         int i;
 128         u8 *buf = (u8 *) 1;
 129
 130         memset(dev->temp_buffer, 0, sizeof(dev->temp_buffer));
 131
 132         for (i = 0; buf && i < YAFFS_N_TEMP_BUFFERS; i++) {
 133                 dev->temp_buffer[i].in_use = 0;
 134                 buf = kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
 135                 dev->temp_buffer[i].buffer = buf;
 136         }
 137
 138         return buf ? YAFFS_OK : YAFFS_FAIL;
 139 }
 140
 141 u8 *yaffs_get_temp_buffer(struct yaffs_dev * dev)
 142 {
 143         int i;
 144
 145         dev->temp_in_use++;
 146         if (dev->temp_in_use > dev->max_temp)
 147                 dev->max_temp = dev->temp_in_use;
 148
 149         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 150                 if (dev->temp_buffer[i].in_use == 0) {
 151                         dev->temp_buffer[i].in_use = 1;
 152                         return dev->temp_buffer[i].buffer;
 153                 }
 154         }
 155
 156         yaffs_trace(YAFFS_TRACE_BUFFERS, "Out of temp buffers");
 157         /*
 158          * If we got here then we have to allocate an unmanaged one
 159          * This is not good.
 160          */
 161
 162         dev->unmanaged_buffer_allocs++;
 163         return kmalloc(dev->data_bytes_per_chunk, GFP_NOFS);
 164
 165 }
 166
 167 void yaffs_release_temp_buffer(struct yaffs_dev *dev, u8 *buffer)
 168 {
 169         int i;
 170
 171         dev->temp_in_use--;
 172
 173         for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++) {
 174                 if (dev->temp_buffer[i].buffer == buffer) {
 175                         dev->temp_buffer[i].in_use = 0;
 176                         return;
 177                 }
 178         }
 179
 180         if (buffer) {
 181                 /* assume it is an unmanaged one. */
 182                 yaffs_trace(YAFFS_TRACE_BUFFERS,
 183                         "Releasing unmanaged temp buffer");
 184                 kfree(buffer);
 185                 dev->unmanaged_buffer_deallocs++;
 186         }
 187
 188 }
 189
 190 /*
 191  * Functions for robustisizing TODO
 192  *
 193  */
 194
 195 static void yaffs_handle_chunk_wr_ok(struct yaffs_dev *dev, int nand_chunk,
 196                                      const u8 *data,
 197                                      const struct yaffs_ext_tags *tags)
 198 {
 199         (void) dev;
 200         (void) nand_chunk;
 201         (void) data;
 202         (void) tags;
 203 }
 204
 205 static void yaffs_handle_chunk_update(struct yaffs_dev *dev, int nand_chunk,
 206                                       const struct yaffs_ext_tags *tags)
 207 {
 208         (void) dev;
 209         (void) nand_chunk;
 210         (void) tags;
 211 }
 212
 213 void yaffs_handle_chunk_error(struct yaffs_dev *dev,
 214                               struct yaffs_block_info *bi)
 215 {
 216         if (!bi->gc_prioritise) {
 217                 bi->gc_prioritise = 1;
 218                 dev->has_pending_prioritised_gc = 1;
 219                 bi->chunk_error_strikes++;
 220
 221                 if (bi->chunk_error_strikes > 3) {
 222                         bi->needs_retiring = 1; /* Too many stikes, so retire */
 223                         yaffs_trace(YAFFS_TRACE_ALWAYS,
 224                                 "yaffs: Block struck out");
 225
 226                 }
 227         }
 228 }
 229
 230 static void yaffs_handle_chunk_wr_error(struct yaffs_dev *dev, int nand_chunk,
 231                                         int erased_ok)
 232 {
 233         int flash_block = nand_chunk / dev->param.chunks_per_block;
 234         struct yaffs_block_info *bi = yaffs_get_block_info(dev, flash_block);
 235
 236         yaffs_handle_chunk_error(dev, bi);
 237
 238         if (erased_ok) {
 239                 /* Was an actual write failure,
 240                  * so mark the block for retirement.*/
 241                 bi->needs_retiring = 1;
 242                 yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
 243                   "**>> Block %d needs retiring", flash_block);
 244         }
 245
 246         /* Delete the chunk */
 247         yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
 248         yaffs_skip_rest_of_block(dev);
 249 }
 250
 251 /*
 252  * Verification code
 253  */
 254
 255 /*
 256  *  Simple hash function. Needs to have a reasonable spread
 257  */
 258
 259 static inline int yaffs_hash_fn(int n)
 260 {
 261         if (n < 0)
 262                 n = -n;
 263         return n % YAFFS_NOBJECT_BUCKETS;
 264 }
 265
 266 /*
 267  * Access functions to useful fake objects.
 268  * Note that root might have a presence in NAND if permissions are set.
 269  */
 270
 271 struct yaffs_obj *yaffs_root(struct yaffs_dev *dev)
 272 {
 273         return dev->root_dir;
 274 }
 275
 276 struct yaffs_obj *yaffs_lost_n_found(struct yaffs_dev *dev)
 277 {
 278         return dev->lost_n_found;
 279 }
 280
 281 /*
 282  *  Erased NAND checking functions
 283  */
 284
 285 int yaffs_check_ff(u8 *buffer, int n_bytes)
 286 {
 287         /* Horrible, slow implementation */
 288         while (n_bytes--) {
 289                 if (*buffer != 0xff)
 290                         return 0;
 291                 buffer++;
 292         }
 293         return 1;
 294 }
 295
 296 static int yaffs_check_chunk_erased(struct yaffs_dev *dev, int nand_chunk)
 297 {
 298         int retval = YAFFS_OK;
 299         u8 *data = yaffs_get_temp_buffer(dev);
 300         struct yaffs_ext_tags tags;
 301
 302         if (!yaffs_rd_chunk_tags_nand(dev, nand_chunk, data, &tags))
 303         {
 304                 yaffs_trace(YAFFS_TRACE_ERROR, "yaffs_check_chunk_erased: unhandled error from rd_chunk_tags_nand");
 305         }
 306
 307
 308         if (tags.ecc_result > YAFFS_ECC_RESULT_NO_ERROR)
 309                 retval = YAFFS_FAIL;
 310
 311         if (!yaffs_check_ff(data, dev->data_bytes_per_chunk) ||
 312                 tags.chunk_used) {
 313                 yaffs_trace(YAFFS_TRACE_NANDACCESS,
 314                         "Chunk %d not erased", nand_chunk);
 315                 retval = YAFFS_FAIL;
 316         }
 317
 318
 319         yaffs_release_temp_buffer(dev, data);
 320
 321         return retval;
 322
 323 }
 324
 325 static int yaffs_verify_chunk_written(struct yaffs_dev *dev,
 326                                       int nand_chunk,
 327                                       const u8 *data,
 328                                       struct yaffs_ext_tags *tags)
 329 {
 330         int retval = YAFFS_OK;
 331         struct yaffs_ext_tags temp_tags;
 332         u8 *buffer = yaffs_get_temp_buffer(dev);
 333
 334         if (!yaffs_rd_chunk_tags_nand(dev, nand_chunk, buffer, &temp_tags))
 335         {
 336                 yaffs_trace(YAFFS_TRACE_ERROR, "yaffs_verify_chunk_written: unhandled error from rd_chunk_tags_nand");
 337         }
 338
 339         if (memcmp(buffer, data, dev->data_bytes_per_chunk) ||
 340             temp_tags.obj_id != tags->obj_id ||
 341             temp_tags.chunk_id != tags->chunk_id ||
 342             temp_tags.n_bytes != tags->n_bytes)
 343                 retval = YAFFS_FAIL;
 344
 345         yaffs_release_temp_buffer(dev, buffer);
 346
 347         return retval;
 348 }
 349
 350
 351 int yaffs_check_alloc_available(struct yaffs_dev *dev, int n_chunks)
 352 {
 353         int reserved_chunks;
 354         int reserved_blocks = dev->param.n_reserved_blocks;
 355         int checkpt_blocks;
 356
 357         checkpt_blocks = yaffs_calc_checkpt_blocks_required(dev);
 358
 359         reserved_chunks =
 360             (reserved_blocks + checkpt_blocks) * dev->param.chunks_per_block;
 361
 362         return (dev->n_free_chunks > (reserved_chunks + n_chunks));
 363 }
 364
 365 static int yaffs_find_alloc_block(struct yaffs_dev *dev)
 366 {
 367         int i;
 368         struct yaffs_block_info *bi;
 369
 370         if (dev->n_erased_blocks < 1) {
 371                 /* Hoosterman we've got a problem.
 372                  * Can't get space to gc
 373                  */
 374                 yaffs_trace(YAFFS_TRACE_ERROR,
 375                   "yaffs tragedy: no more erased blocks");
 376
 377                 return -1;
 378         }
 379
 380         /* Find an empty block. */
 381
 382         for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
 383                 dev->alloc_block_finder++;
 384                 if (dev->alloc_block_finder < dev->internal_start_block
 385                     || dev->alloc_block_finder > dev->internal_end_block) {
 386                         dev->alloc_block_finder = dev->internal_start_block;
 387                 }
 388
 389                 bi = yaffs_get_block_info(dev, dev->alloc_block_finder);
 390
 391                 if (bi->block_state == YAFFS_BLOCK_STATE_EMPTY) {
 392                         bi->block_state = YAFFS_BLOCK_STATE_ALLOCATING;
 393                         dev->seq_number++;
 394                         bi->seq_number = dev->seq_number;
 395                         dev->n_erased_blocks--;
 396                         yaffs_trace(YAFFS_TRACE_ALLOCATE,
 397                           "Allocated block %d, seq  %d, %d left" ,
 398                            dev->alloc_block_finder, dev->seq_number,
 399                            dev->n_erased_blocks);
 400                         return dev->alloc_block_finder;
 401                 }
 402         }
 403
 404         yaffs_trace(YAFFS_TRACE_ALWAYS,
 405                 "yaffs tragedy: no more erased blocks, but there should have been %d",
 406                 dev->n_erased_blocks);
 407
 408         return -1;
 409 }
 410
 411 static int yaffs_alloc_chunk(struct yaffs_dev *dev, int use_reserver,
 412                              struct yaffs_block_info **block_ptr)
 413 {
 414         int ret_val;
 415         struct yaffs_block_info *bi;
 416
 417         if (dev->alloc_block < 0) {
 418                 /* Get next block to allocate off */
 419                 dev->alloc_block = yaffs_find_alloc_block(dev);
 420                 dev->alloc_page = 0;
 421         }
 422
 423         if (!use_reserver && !yaffs_check_alloc_available(dev, 1)) {
 424                 /* No space unless we're allowed to use the reserve. */
 425                 return -1;
 426         }
 427
 428         if (dev->n_erased_blocks < dev->param.n_reserved_blocks
 429             && dev->alloc_page == 0)
 430                 yaffs_trace(YAFFS_TRACE_ALLOCATE, "Allocating reserve");
 431
 432         /* Next page please.... */
 433         if (dev->alloc_block >= 0) {
 434                 bi = yaffs_get_block_info(dev, dev->alloc_block);
 435
 436                 ret_val = (dev->alloc_block * dev->param.chunks_per_block) +
 437                     dev->alloc_page;
 438                 bi->pages_in_use++;
 439                 yaffs_set_chunk_bit(dev, dev->alloc_block, dev->alloc_page);
 440
 441                 dev->alloc_page++;
 442
 443                 dev->n_free_chunks--;
 444
 445                 /* If the block is full set the state to full */
 446                 if (dev->alloc_page >= (u32)dev->param.chunks_per_block) {
 447                         bi->block_state = YAFFS_BLOCK_STATE_FULL;
 448                         dev->alloc_block = -1;
 449                 }
 450
 451                 if (block_ptr)
 452                         *block_ptr = bi;
 453
 454                 return ret_val;
 455         }
 456
 457         yaffs_trace(YAFFS_TRACE_ERROR,
 458                 "!!!!!!!!! Allocator out !!!!!!!!!!!!!!!!!");
 459
 460         return -1;
 461 }
 462
 463 static int yaffs_get_erased_chunks(struct yaffs_dev *dev)
 464 {
 465         int n;
 466
 467         n = dev->n_erased_blocks * dev->param.chunks_per_block;
 468
 469         if (dev->alloc_block > 0)
 470                 n += (dev->param.chunks_per_block - dev->alloc_page);
 471
 472         return n;
 473
 474 }
 475
 476 /*
 477  * yaffs_skip_rest_of_block() skips over the rest of the allocation block
 478  * if we don't want to write to it.
 479  */
 480 void yaffs_skip_rest_of_block(struct yaffs_dev *dev)
 481 {
 482         struct yaffs_block_info *bi;
 483
 484         if (dev->alloc_block > 0) {
 485                 bi = yaffs_get_block_info(dev, dev->alloc_block);
 486                 if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING) {
 487                         bi->block_state = YAFFS_BLOCK_STATE_FULL;
 488                         dev->alloc_block = -1;
 489                 }
 490         }
 491 }
 492
 493 static int yaffs_write_new_chunk(struct yaffs_dev *dev,
 494                                  const u8 *data,
 495                                  struct yaffs_ext_tags *tags, int use_reserver)
 496 {
 497         u32 attempts = 0;
 498         int write_ok = 0;
 499         int chunk;
 500
 501         yaffs2_checkpt_invalidate(dev);
 502
 503         do {
 504                 struct yaffs_block_info *bi = 0;
 505                 int erased_ok = 0;
 506
 507                 chunk = yaffs_alloc_chunk(dev, use_reserver, &bi);
 508                 if (chunk < 0) {
 509                         /* no space */
 510                         break;
 511                 }
 512
 513                 /* First check this chunk is erased, if it needs
 514                  * checking.  The checking policy (unless forced
 515                  * always on) is as follows:
 516                  *
 517                  * Check the first page we try to write in a block.
 518                  * If the check passes then we don't need to check any
 519                  * more.        If the check fails, we check again...
 520                  * If the block has been erased, we don't need to check.
 521                  *
 522                  * However, if the block has been prioritised for gc,
 523                  * then we think there might be something odd about
 524                  * this block and stop using it.
 525                  *
 526                  * Rationale: We should only ever see chunks that have
 527                  * not been erased if there was a partially written
 528                  * chunk due to power loss.  This checking policy should
 529                  * catch that case with very few checks and thus save a
 530                  * lot of checks that are most likely not needed.
 531                  *
 532                  * Mods to the above
 533                  * If an erase check fails or the write fails we skip the
 534                  * rest of the block.
 535                  */
 536
 537                 /* let's give it a try */
 538                 attempts++;
 539
 540                 if (dev->param.always_check_erased)
 541                         bi->skip_erased_check = 0;
 542
 543                 if (!bi->skip_erased_check) {
 544                         erased_ok = yaffs_check_chunk_erased(dev, chunk);
 545                         if (erased_ok != YAFFS_OK) {
 546                                 yaffs_trace(YAFFS_TRACE_ERROR,
 547                                   "**>> yaffs chunk %d was not erased",
 548                                   chunk);
 549
 550                                 /* If not erased, delete this one,
 551                                  * skip rest of block and
 552                                  * try another chunk */
 553                                 yaffs_chunk_del(dev, chunk, 1, __LINE__);
 554                                 yaffs_skip_rest_of_block(dev);
 555                                 continue;
 556                         }
 557                 }
 558
 559                 write_ok = yaffs_wr_chunk_tags_nand(dev, chunk, data, tags);
 560
 561                 if (!bi->skip_erased_check)
 562                         write_ok =
 563                             yaffs_verify_chunk_written(dev, chunk, data, tags);
 564
 565                 if (write_ok != YAFFS_OK) {
 566                         /* Clean up aborted write, skip to next block and
 567                          * try another chunk */
 568                         yaffs_handle_chunk_wr_error(dev, chunk, erased_ok);
 569                         continue;
 570                 }
 571
 572                 bi->skip_erased_check = 1;
 573
 574                 /* Copy the data into the robustification buffer */
 575                 yaffs_handle_chunk_wr_ok(dev, chunk, data, tags);
 576
 577         } while (write_ok != YAFFS_OK &&
 578                  (yaffs_wr_attempts <= 0 || attempts <= yaffs_wr_attempts));
 579
 580         if (!write_ok)
 581                 chunk = -1;
 582
 583         if (attempts > 1) {
 584                 yaffs_trace(YAFFS_TRACE_ERROR,
 585                         "**>> yaffs write required %d attempts",
 586                         attempts);
 587                 dev->n_retried_writes += (attempts - 1);
 588         }
 589
 590         return chunk;
 591 }
 592
 593 /*
 594  * Block retiring for handling a broken block.
 595  */
 596
 597 static void yaffs_retire_block(struct yaffs_dev *dev, int flash_block)
 598 {
 599         struct yaffs_block_info *bi = yaffs_get_block_info(dev, flash_block);
 600
 601         yaffs2_checkpt_invalidate(dev);
 602
 603         yaffs2_clear_oldest_dirty_seq(dev, bi);
 604
 605         if (yaffs_mark_bad(dev, flash_block) != YAFFS_OK) {
 606                 if (yaffs_erase_block(dev, flash_block) != YAFFS_OK) {
 607                         yaffs_trace(YAFFS_TRACE_ALWAYS,
 608                                 "yaffs: Failed to mark bad and erase block %d",
 609                                 flash_block);
 610                 } else {
 611                         struct yaffs_ext_tags tags;
 612                         int chunk_id =
 613                             flash_block * dev->param.chunks_per_block;
 614
 615                         u8 *buffer = yaffs_get_temp_buffer(dev);
 616
 617                         memset(buffer, 0xff, dev->data_bytes_per_chunk);
 618                         memset(&tags, 0, sizeof(tags));
 619                         tags.seq_number = YAFFS_SEQUENCE_BAD_BLOCK;
 620                         if (dev->tagger.write_chunk_tags_fn(dev, chunk_id -
 621                                                         dev->chunk_offset,
 622                                                         buffer,
 623                                                         &tags) != YAFFS_OK)
 624                                 yaffs_trace(YAFFS_TRACE_ALWAYS,
 625                                         "yaffs: Failed to write bad block marker to block %d",
 626                                         flash_block);
 627
 628                         yaffs_release_temp_buffer(dev, buffer);
 629                 }
 630         }
 631
 632         bi->block_state = YAFFS_BLOCK_STATE_DEAD;
 633         bi->gc_prioritise = 0;
 634         bi->needs_retiring = 0;
 635
 636         dev->n_retired_blocks++;
 637 }
 638
 639 /*---------------- Name handling functions ------------*/
 640
 641 static void yaffs_load_name_from_oh(struct yaffs_dev *dev, YCHAR *name,
 642                                     const YCHAR *oh_name, int buff_size)
 643 {
 644 #ifdef CONFIG_YAFFS_AUTO_UNICODE
 645         if (dev->param.auto_unicode) {
 646                 if (*oh_name) {
 647                         /* It is an ASCII name, do an ASCII to
 648                          * unicode conversion */
 649                         const char *ascii_oh_name = (const char *)oh_name;
 650                         int n = buff_size - 1;
 651                         while (n > 0 && *ascii_oh_name) {
 652                                 *name = *ascii_oh_name;
 653                                 name++;
 654                                 ascii_oh_name++;
 655                                 n--;
 656                         }
 657                 } else {
 658                         yaffs_strncpy(name, oh_name + 1, buff_size - 1);
 659                 }
 660         } else {
 661 #else
 662         (void) dev;
 663         {
 664 #endif
 665                 yaffs_strncpy(name, oh_name, buff_size - 1);
 666         }
 667 }
 668
 669 static void yaffs_load_oh_from_name(struct yaffs_dev *dev, YCHAR *oh_name,
 670                                     const YCHAR *name)
 671 {
 672 #ifdef CONFIG_YAFFS_AUTO_UNICODE
 673
 674         int is_ascii;
 675         const YCHAR *w;
 676
 677         if (dev->param.auto_unicode) {
 678
 679                 is_ascii = 1;
 680                 w = name;
 681
 682                 /* Figure out if the name will fit in ascii character set */
 683                 while (is_ascii && *w) {
 684                         if ((*w) & 0xff00)
 685                                 is_ascii = 0;
 686                         w++;
 687                 }
 688
 689                 if (is_ascii) {
 690                         /* It is an ASCII name, so convert unicode to ascii */
 691                         char *ascii_oh_name = (char *)oh_name;
 692                         int n = YAFFS_MAX_NAME_LENGTH - 1;
 693                         while (n > 0 && *name) {
 694                                 *ascii_oh_name = *name;
 695                                 name++;
 696                                 ascii_oh_name++;
 697                                 n--;
 698                         }
 699                 } else {
 700                         /* Unicode name, so save starting at the second YCHAR */
 701                         *oh_name = 0;
 702                         yaffs_strncpy(oh_name + 1, name, YAFFS_MAX_NAME_LENGTH - 2);
 703                 }
 704         } else {
 705 #else
 706         dev = dev;
 707         {
 708 #endif
 709                 yaffs_strncpy(oh_name, name, YAFFS_MAX_NAME_LENGTH - 1);
 710         }
 711 }
 712
 713 static u16 yaffs_calc_name_sum(const YCHAR *name)
 714 {
 715         u16 sum = 0;
 716         u16 i = 1;
 717
 718         if (!name)
 719                 return 0;
 720
 721         while ((*name) && i < (YAFFS_MAX_NAME_LENGTH / 2)) {
 722
 723                 /* 0x1f mask is case insensitive */
 724                 sum += ((*name) & 0x1f) * i;
 725                 i++;
 726                 name++;
 727         }
 728         return sum;
 729 }
 730
 731
 732 void yaffs_set_obj_name(struct yaffs_obj *obj, const YCHAR * name)
 733 {
 734         memset(obj->short_name, 0, sizeof(obj->short_name));
 735
 736         if (name && !name[0]) {
 737                 yaffs_fix_null_name(obj, obj->short_name,
 738                                 YAFFS_SHORT_NAME_LENGTH);
 739                 name = obj->short_name;
 740         } else if (name &&
 741                 yaffs_strnlen(name, YAFFS_SHORT_NAME_LENGTH + 1) <=
 742                 YAFFS_SHORT_NAME_LENGTH)  {
 743                 yaffs_strcpy(obj->short_name, name);
 744         }
 745
 746         obj->sum = yaffs_calc_name_sum(name);
 747 }
 748
 749 void yaffs_set_obj_name_from_oh(struct yaffs_obj *obj,
 750                                 const struct yaffs_obj_hdr *oh)
 751 {
 752 #ifdef CONFIG_YAFFS_AUTO_UNICODE
 753         YCHAR tmp_name[YAFFS_MAX_NAME_LENGTH + 1];
 754         memset(tmp_name, 0, sizeof(tmp_name));
 755         yaffs_load_name_from_oh(obj->my_dev, tmp_name, oh->name,
 756                                 YAFFS_MAX_NAME_LENGTH + 1);
 757         yaffs_set_obj_name(obj, tmp_name);
 758 #else
 759         yaffs_set_obj_name(obj, oh->name);
 760 #endif
 761 }
 762
 763 Y_LOFF_T yaffs_max_file_size(struct yaffs_dev *dev)
 764 {
 765         if(sizeof(Y_LOFF_T) < 8)
 766                 return YAFFS_MAX_FILE_SIZE_32;
 767         else
 768                 return ((Y_LOFF_T) YAFFS_MAX_CHUNK_ID) * dev->data_bytes_per_chunk;
 769 }
 770
 771 /*-------------------- TNODES -------------------
 772
 773  * List of spare tnodes
 774  * The list is hooked together using the first pointer
 775  * in the tnode.
 776  */
 777
 778 struct yaffs_tnode *yaffs_get_tnode(struct yaffs_dev *dev)
 779 {
 780         struct yaffs_tnode *tn = yaffs_alloc_raw_tnode(dev);
 781
 782         if (tn) {
 783                 memset(tn, 0, dev->tnode_size);
 784                 dev->n_tnodes++;
 785         }
 786
 787         dev->checkpoint_blocks_required = 0;    /* force recalculation */
 788
 789         return tn;
 790 }
 791
 792 /* FreeTnode frees up a tnode and puts it back on the free list */
 793 static void yaffs_free_tnode(struct yaffs_dev *dev, struct yaffs_tnode *tn)
 794 {
 795         yaffs_free_raw_tnode(dev, tn);
 796         dev->n_tnodes--;
 797         dev->checkpoint_blocks_required = 0;    /* force recalculation */
 798 }
 799
 800 static void yaffs_deinit_tnodes_and_objs(struct yaffs_dev *dev)
 801 {
 802         yaffs_deinit_raw_tnodes_and_objs(dev);
 803         dev->n_obj = 0;
 804         dev->n_tnodes = 0;
 805 }
 806
 807 static void yaffs_load_tnode_0(struct yaffs_dev *dev, struct yaffs_tnode *tn,
 808                         unsigned pos, unsigned val)
 809 {
 810         u32 *map = (u32 *) tn;
 811         u32 bit_in_map;
 812         u32 bit_in_word;
 813         u32 word_in_map;
 814         u32 mask;
 815
 816         pos &= YAFFS_TNODES_LEVEL0_MASK;
 817         val >>= dev->chunk_grp_bits;
 818
 819         bit_in_map = pos * dev->tnode_width;
 820         word_in_map = bit_in_map / 32;
 821         bit_in_word = bit_in_map & (32 - 1);
 822
 823         mask = dev->tnode_mask << bit_in_word;
 824
 825         map[word_in_map] &= ~mask;
 826         map[word_in_map] |= (mask & (val << bit_in_word));
 827
 828         if (dev->tnode_width > (32 - bit_in_word)) {
 829                 bit_in_word = (32 - bit_in_word);
 830                 word_in_map++;
 831                 mask =
 832                     dev->tnode_mask >> bit_in_word;
 833                 map[word_in_map] &= ~mask;
 834                 map[word_in_map] |= (mask & (val >> bit_in_word));
 835         }
 836 }
 837
 838 u32 yaffs_get_group_base(struct yaffs_dev *dev, struct yaffs_tnode *tn,
 839                          unsigned pos)
 840 {
 841         u32 *map = (u32 *) tn;
 842         u32 bit_in_map;
 843         u32 bit_in_word;
 844         u32 word_in_map;
 845         u32 val;
 846
 847         pos &= YAFFS_TNODES_LEVEL0_MASK;
 848
 849         bit_in_map = pos * dev->tnode_width;
 850         word_in_map = bit_in_map / 32;
 851         bit_in_word = bit_in_map & (32 - 1);
 852
 853         val = map[word_in_map] >> bit_in_word;
 854
 855         if (dev->tnode_width > (32 - bit_in_word)) {
 856                 bit_in_word = (32 - bit_in_word);
 857                 word_in_map++;
 858                 val |= (map[word_in_map] << bit_in_word);
 859         }
 860
 861         val &= dev->tnode_mask;
 862         val <<= dev->chunk_grp_bits;
 863
 864         return val;
 865 }
 866
 867 /* ------------------- End of individual tnode manipulation -----------------*/
 868
 869 /* ---------Functions to manipulate the look-up tree (made up of tnodes) ------
 870  * The look up tree is represented by the top tnode and the number of top_level
 871  * in the tree. 0 means only the level 0 tnode is in the tree.
 872  */
 873
 874 /* FindLevel0Tnode finds the level 0 tnode, if one exists. */
 875 struct yaffs_tnode *yaffs_find_tnode_0(struct yaffs_dev *dev,
 876                                        struct yaffs_file_var *file_struct,
 877                                        u32 chunk_id)
 878 {
 879         struct yaffs_tnode *tn = file_struct->top;
 880         u32 i;
 881         int required_depth;
 882         int level = file_struct->top_level;
 883
 884         (void) dev;
 885
 886         /* Check sane level and chunk Id */
 887         if (level < 0 || level > YAFFS_TNODES_MAX_LEVEL)
 888                 return NULL;
 889
 890         if (chunk_id > YAFFS_MAX_CHUNK_ID)
 891                 return NULL;
 892
 893         /* First check we're tall enough (ie enough top_level) */
 894
 895         i = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
 896         required_depth = 0;
 897         while (i) {
 898                 i >>= YAFFS_TNODES_INTERNAL_BITS;
 899                 required_depth++;
 900         }
 901
 902         if (required_depth > file_struct->top_level)
 903                 return NULL;    /* Not tall enough, so we can't find it */
 904
 905         /* Traverse down to level 0 */
 906         while (level > 0 && tn) {
 907                 tn = tn->internal[(chunk_id >>
 908                                    (YAFFS_TNODES_LEVEL0_BITS +
 909                                     (level - 1) *
 910                                     YAFFS_TNODES_INTERNAL_BITS)) &
 911                                   YAFFS_TNODES_INTERNAL_MASK];
 912                 level--;
 913         }
 914
 915         return tn;
 916 }
 917
 918 /* add_find_tnode_0 finds the level 0 tnode if it exists,
 919  * otherwise first expands the tree.
 920  * This happens in two steps:
 921  *  1. If the tree isn't tall enough, then make it taller.
 922  *  2. Scan down the tree towards the level 0 tnode adding tnodes if required.
 923  *
 924  * Used when modifying the tree.
 925  *
 926  *  If the tn argument is NULL, then a fresh tnode will be added otherwise the
 927  *  specified tn will be plugged into the ttree.
 928  */
 929
 930 struct yaffs_tnode *yaffs_add_find_tnode_0(struct yaffs_dev *dev,
 931                                            struct yaffs_file_var *file_struct,
 932                                            u32 chunk_id,
 933                                            struct yaffs_tnode *passed_tn)
 934 {
 935         int required_depth;
 936         int i;
 937         int l;
 938         struct yaffs_tnode *tn;
 939         u32 x;
 940
 941         /* Check sane level and page Id */
 942         if (file_struct->top_level < 0 ||
 943             file_struct->top_level > YAFFS_TNODES_MAX_LEVEL)
 944                 return NULL;
 945
 946         if (chunk_id > YAFFS_MAX_CHUNK_ID)
 947                 return NULL;
 948
 949         /* First check we're tall enough (ie enough top_level) */
 950
 951         x = chunk_id >> YAFFS_TNODES_LEVEL0_BITS;
 952         required_depth = 0;
 953         while (x) {
 954                 x >>= YAFFS_TNODES_INTERNAL_BITS;
 955                 required_depth++;
 956         }
 957
 958         if (required_depth > file_struct->top_level) {
 959                 /* Not tall enough, gotta make the tree taller */
 960                 for (i = file_struct->top_level; i < required_depth; i++) {
 961
 962                         tn = yaffs_get_tnode(dev);
 963
 964                         if (tn) {
 965                                 tn->internal[0] = file_struct->top;
 966                                 file_struct->top = tn;
 967                                 file_struct->top_level++;
 968                         } else {
 969                                 yaffs_trace(YAFFS_TRACE_ERROR,
 970                                         "yaffs: no more tnodes");
 971                                 return NULL;
 972                         }
 973                 }
 974         }
 975
 976         /* Traverse down to level 0, adding anything we need */
 977
 978         l = file_struct->top_level;
 979         tn = file_struct->top;
 980
 981         if (l > 0) {
 982                 while (l > 0 && tn) {
 983                         x = (chunk_id >>
 984                              (YAFFS_TNODES_LEVEL0_BITS +
 985                               (l - 1) * YAFFS_TNODES_INTERNAL_BITS)) &
 986                             YAFFS_TNODES_INTERNAL_MASK;
 987
 988                         if ((l > 1) && !tn->internal[x]) {
 989                                 /* Add missing non-level-zero tnode */
 990                                 tn->internal[x] = yaffs_get_tnode(dev);
 991                                 if (!tn->internal[x])
 992                                         return NULL;
 993                         } else if (l == 1) {
 994                                 /* Looking from level 1 at level 0 */
 995                                 if (passed_tn) {
 996                                         /* If we already have one, release it */
 997                                         if (tn->internal[x])
 998                                                 yaffs_free_tnode(dev,
 999                                                         tn->internal[x]);
1000                                         tn->internal[x] = passed_tn;
1001
1002                                 } else if (!tn->internal[x]) {
1003                                         /* Don't have one, none passed in */
1004                                         tn->internal[x] = yaffs_get_tnode(dev);
1005                                         if (!tn->internal[x])
1006                                                 return NULL;
1007                                 }
1008                         }
1009
1010                         tn = tn->internal[x];
1011                         l--;
1012                 }
1013         } else {
1014                 /* top is level 0 */
1015                 if (passed_tn) {
1016                         memcpy(tn, passed_tn,
1017                                (dev->tnode_width * YAFFS_NTNODES_LEVEL0) / 8);
1018                         yaffs_free_tnode(dev, passed_tn);
1019                 }
1020         }
1021
1022         return tn;
1023 }
1024
1025 static int yaffs_tags_match(const struct yaffs_ext_tags *tags, unsigned int obj_id,
1026                             unsigned int chunk_obj)
1027 {
1028         return (tags->chunk_id == chunk_obj &&
1029                 tags->obj_id == obj_id &&
1030                 !tags->is_deleted) ? 1 : 0;
1031
1032 }
1033
1034 static int yaffs_find_chunk_in_group(struct yaffs_dev *dev, int the_chunk,
1035                                         struct yaffs_ext_tags *tags, int obj_id,
1036                                         int inode_chunk)
1037 {
1038         int j;
1039
1040         for (j = 0; the_chunk && j < dev->chunk_grp_size; j++) {
1041                 if (yaffs_check_chunk_bit
1042                     (dev, the_chunk / dev->param.chunks_per_block,
1043                      the_chunk % dev->param.chunks_per_block)) {
1044
1045                         if (dev->chunk_grp_size == 1)
1046                                 return the_chunk;
1047                         else {
1048                                 if (!yaffs_rd_chunk_tags_nand(dev, the_chunk, NULL, tags))
1049                                 {
1050                                         yaffs_trace(YAFFS_TRACE_ERROR,
1051                                             "yaffs_find_chunk_in_group: unhandled error from rd_chunk_tags_nand");
1052                                 }
1053                                 if (yaffs_tags_match(tags,
1054                                                         obj_id, inode_chunk)) {
1055                                         /* found it; */
1056                                         return the_chunk;
1057                                 }
1058                         }
1059                 }
1060                 the_chunk++;
1061         }
1062         return -1;
1063 }
1064
1065 int yaffs_find_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
1066                                     struct yaffs_ext_tags *tags)
1067 {
1068         /*Get the Tnode, then get the level 0 offset chunk offset */
1069         struct yaffs_tnode *tn;
1070         int the_chunk = -1;
1071         struct yaffs_ext_tags local_tags;
1072         int ret_val = -1;
1073         struct yaffs_dev *dev = in->my_dev;
1074
1075         if (!tags) {
1076                 /* Passed a NULL, so use our own tags space */
1077                 tags = &local_tags;
1078         }
1079
1080         tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
1081
1082         if (!tn)
1083                 return ret_val;
1084
1085         the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
1086
1087         ret_val = yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
1088                                               inode_chunk);
1089         return ret_val;
1090 }
1091
1092 static int yaffs_find_del_file_chunk(struct yaffs_obj *in, int inode_chunk,
1093                                      struct yaffs_ext_tags *tags)
1094 {
1095         /* Get the Tnode, then get the level 0 offset chunk offset */
1096         struct yaffs_tnode *tn;
1097         int the_chunk = -1;
1098         struct yaffs_ext_tags local_tags;
1099         struct yaffs_dev *dev = in->my_dev;
1100         int ret_val = -1;
1101
1102         if (!tags) {
1103                 /* Passed a NULL, so use our own tags space */
1104                 tags = &local_tags;
1105         }
1106
1107         tn = yaffs_find_tnode_0(dev, &in->variant.file_variant, inode_chunk);
1108
1109         if (!tn)
1110                 return ret_val;
1111
1112         the_chunk = yaffs_get_group_base(dev, tn, inode_chunk);
1113
1114         ret_val = yaffs_find_chunk_in_group(dev, the_chunk, tags, in->obj_id,
1115                                               inode_chunk);
1116
1117         /* Delete the entry in the filestructure (if found) */
1118         if (ret_val != -1)
1119                 yaffs_load_tnode_0(dev, tn, inode_chunk, 0);
1120
1121         return ret_val;
1122 }
1123
1124 int yaffs_put_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
1125                             int nand_chunk, int in_scan)
1126 {
1127         /* NB in_scan is zero unless scanning.
1128          * For forward scanning, in_scan is > 0;
1129          * for backward scanning in_scan is < 0
1130          *
1131          * nand_chunk = 0 is a dummy insert to make sure the tnodes are there.
1132          */
1133
1134         struct yaffs_tnode *tn;
1135         struct yaffs_dev *dev = in->my_dev;
1136         int existing_cunk;
1137         struct yaffs_ext_tags existing_tags;
1138         struct yaffs_ext_tags new_tags;
1139         unsigned existing_serial, new_serial;
1140
1141         if (in->variant_type != YAFFS_OBJECT_TYPE_FILE) {
1142                 /* Just ignore an attempt at putting a chunk into a non-file
1143                  * during scanning.
1144                  * If it is not during Scanning then something went wrong!
1145                  */
1146                 if (!in_scan) {
1147                         yaffs_trace(YAFFS_TRACE_ERROR,
1148                                 "yaffs tragedy:attempt to put data chunk into a non-file"
1149                                 );
1150                         BUG();
1151                 }
1152
1153                 yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
1154                 return YAFFS_OK;
1155         }
1156
1157         tn = yaffs_add_find_tnode_0(dev,
1158                                     &in->variant.file_variant,
1159                                     inode_chunk, NULL);
1160         if (!tn)
1161                 return YAFFS_FAIL;
1162
1163         if (!nand_chunk)
1164                 /* Dummy insert, bail now */
1165                 return YAFFS_OK;
1166
1167         existing_cunk = yaffs_get_group_base(dev, tn, inode_chunk);
1168
1169         if (in_scan != 0) {
1170                 /* If we're scanning then we need to test for duplicates
1171                  * NB This does not need to be efficient since it should only
1172                  * happen when the power fails during a write, then only one
1173                  * chunk should ever be affected.
1174                  *
1175                  * Correction for YAFFS2: This could happen quite a lot and we
1176                  * need to think about efficiency! TODO
1177                  * Update: For backward scanning we don't need to re-read tags
1178                  * so this is quite cheap.
1179                  */
1180
1181                 if (existing_cunk > 0) {
1182                         /* NB Right now existing chunk will not be real
1183                          * chunk_id if the chunk group size > 1
1184                          * thus we have to do a FindChunkInFile to get the
1185                          * real chunk id.
1186                          *
1187                          * We have a duplicate now we need to decide which
1188                          * one to use:
1189                          *
1190                          * Backwards scanning YAFFS2: The old one is what
1191                          * we use, dump the new one.
1192                          * YAFFS1: Get both sets of tags and compare serial
1193                          * numbers.
1194                          */
1195
1196                         if (in_scan > 0) {
1197                                 /* Only do this for forward scanning */
1198                                 if (!yaffs_rd_chunk_tags_nand(dev,
1199                                                          nand_chunk,
1200                                                          NULL, &new_tags))
1201
1202                                 {
1203                                         yaffs_trace(YAFFS_TRACE_ERROR, "yaffs_put_chunk_in_file: unhandled error from rd_chunk_tags_nand");
1204                                 }
1205
1206                                 /* Do a proper find */
1207                                 existing_cunk =
1208                                     yaffs_find_chunk_in_file(in, inode_chunk,
1209                                                              &existing_tags);
1210                         }
1211
1212                         if (existing_cunk <= 0) {
1213                                 /*Hoosterman - how did this happen? */
1214
1215                                 yaffs_trace(YAFFS_TRACE_ERROR,
1216                                         "yaffs tragedy: existing chunk < 0 in scan"
1217                                         );
1218
1219                         }
1220
1221                         /* NB The deleted flags should be false, otherwise
1222                          * the chunks will not be loaded during a scan
1223                          */
1224
1225                         if (in_scan > 0) {
1226                                 new_serial = new_tags.serial_number;
1227                                 existing_serial = existing_tags.serial_number;
1228                         }
1229
1230                         if ((in_scan > 0) &&
1231                             (existing_cunk <= 0 ||
1232                              ((existing_serial + 1) & 3) == new_serial)) {
1233                                 /* Forward scanning.
1234                                  * Use new
1235                                  * Delete the old one and drop through to
1236                                  * update the tnode
1237                                  */
1238                                 yaffs_chunk_del(dev, existing_cunk, 1,
1239                                                 __LINE__);
1240                         } else {
1241                                 /* Backward scanning or we want to use the
1242                                  * existing one
1243                                  * Delete the new one and return early so that
1244                                  * the tnode isn't changed
1245                                  */
1246                                 yaffs_chunk_del(dev, nand_chunk, 1, __LINE__);
1247                                 return YAFFS_OK;
1248                         }
1249                 }
1250
1251         }
1252
1253         if (existing_cunk == 0)
1254                 in->n_data_chunks++;
1255
1256         yaffs_load_tnode_0(dev, tn, inode_chunk, nand_chunk);
1257
1258         return YAFFS_OK;
1259 }
1260
1261 static void yaffs_soft_del_chunk(struct yaffs_dev *dev, int chunk)
1262 {
1263         struct yaffs_block_info *the_block;
1264         unsigned block_no;
1265
1266         yaffs_trace(YAFFS_TRACE_DELETION, "soft delete chunk %d", chunk);
1267
1268         block_no = chunk / dev->param.chunks_per_block;
1269         the_block = yaffs_get_block_info(dev, block_no);
1270         if (the_block) {
1271                 the_block->soft_del_pages++;
1272                 dev->n_free_chunks++;
1273                 yaffs2_update_oldest_dirty_seq(dev, block_no, the_block);
1274         }
1275 }
1276
1277 /* SoftDeleteWorker scans backwards through the tnode tree and soft deletes all
1278  * the chunks in the file.
1279  * All soft deleting does is increment the block's softdelete count and pulls
1280  * the chunk out of the tnode.
1281  * Thus, essentially this is the same as DeleteWorker except that the chunks
1282  * are soft deleted.
1283  */
1284
1285 static int yaffs_soft_del_worker(struct yaffs_obj *in, struct yaffs_tnode *tn,
1286                                  u32 level, int chunk_offset)
1287 {
1288         int i;
1289         int the_chunk;
1290         int all_done = 1;
1291         struct yaffs_dev *dev = in->my_dev;
1292
1293         if (!tn)
1294                 return 1;
1295
1296         if (level > 0) {
1297                 for (i = YAFFS_NTNODES_INTERNAL - 1;
1298                         all_done && i >= 0;
1299                         i--) {
1300                         if (tn->internal[i]) {
1301                                 all_done =
1302                                     yaffs_soft_del_worker(in,
1303                                         tn->internal[i],
1304                                         level - 1,
1305                                         (chunk_offset <<
1306                                         YAFFS_TNODES_INTERNAL_BITS)
1307                                         + i);
1308                                 if (all_done) {
1309                                         yaffs_free_tnode(dev,
1310                                                 tn->internal[i]);
1311                                         tn->internal[i] = NULL;
1312                                 } else {
1313                                         /* Can this happen? */
1314                                 }
1315                         }
1316                 }
1317                 return (all_done) ? 1 : 0;
1318         }
1319
1320         /* level 0 */
1321          for (i = YAFFS_NTNODES_LEVEL0 - 1; i >= 0; i--) {
1322                 the_chunk = yaffs_get_group_base(dev, tn, i);
1323                 if (the_chunk) {
1324                         yaffs_soft_del_chunk(dev, the_chunk);
1325                         yaffs_load_tnode_0(dev, tn, i, 0);
1326                 }
1327         }
1328         return 1;
1329 }
1330
1331 static void yaffs_remove_obj_from_dir(struct yaffs_obj *obj)
1332 {
1333         struct yaffs_dev *dev = obj->my_dev;
1334         struct yaffs_obj *parent;
1335
1336         yaffs_verify_obj_in_dir(obj);
1337         parent = obj->parent;
1338
1339         yaffs_verify_dir(parent);
1340
1341         if (dev && dev->param.remove_obj_fn)
1342                 dev->param.remove_obj_fn(obj);
1343
1344         list_del_init(&obj->siblings);
1345         obj->parent = NULL;
1346
1347         yaffs_verify_dir(parent);
1348 }
1349
1350 void yaffs_add_obj_to_dir(struct yaffs_obj *directory, struct yaffs_obj *obj)
1351 {
1352         if (!directory) {
1353                 yaffs_trace(YAFFS_TRACE_ALWAYS,
1354                         "tragedy: Trying to add an object to a null pointer directory"
1355                         );
1356                 BUG();
1357                 return;
1358         }
1359         if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
1360                 yaffs_trace(YAFFS_TRACE_ALWAYS,
1361                         "tragedy: Trying to add an object to a non-directory"
1362                         );
1363                 BUG();
1364         }
1365
1366         if (obj->siblings.prev == NULL) {
1367                 /* Not initialised */
1368                 BUG();
1369         }
1370
1371         yaffs_verify_dir(directory);
1372
1373         yaffs_remove_obj_from_dir(obj);
1374
1375         /* Now add it */
1376         list_add(&obj->siblings, &directory->variant.dir_variant.children);
1377         obj->parent = directory;
1378
1379         if (directory == obj->my_dev->unlinked_dir
1380             || directory == obj->my_dev->del_dir) {
1381                 obj->unlinked = 1;
1382                 obj->my_dev->n_unlinked_files++;
1383                 obj->rename_allowed = 0;
1384         }
1385
1386         yaffs_verify_dir(directory);
1387         yaffs_verify_obj_in_dir(obj);
1388 }
1389
1390 static int yaffs_change_obj_name(struct yaffs_obj *obj,
1391                                  struct yaffs_obj *new_dir,
1392                                  const YCHAR *new_name, int force, int shadows)
1393 {
1394         int unlink_op;
1395         int del_op;
1396         struct yaffs_obj *existing_target;
1397
1398         if (new_dir == NULL)
1399                 new_dir = obj->parent;  /* use the old directory */
1400
1401         if (new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
1402                 yaffs_trace(YAFFS_TRACE_ALWAYS,
1403                         "tragedy: yaffs_change_obj_name: new_dir is not a directory"
1404                         );
1405                 BUG();
1406         }
1407
1408         unlink_op = (new_dir == obj->my_dev->unlinked_dir);
1409         del_op = (new_dir == obj->my_dev->del_dir);
1410
1411         existing_target = yaffs_find_by_name(new_dir, new_name);
1412
1413         /* If the object is a file going into the unlinked directory,
1414          *   then it is OK to just stuff it in since duplicate names are OK.
1415          *   else only proceed if the new name does not exist and we're putting
1416          *   it into a directory.
1417          */
1418         if (!(unlink_op || del_op || force ||
1419               shadows > 0 || !existing_target) ||
1420               new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
1421                 return YAFFS_FAIL;
1422
1423         yaffs_set_obj_name(obj, new_name);
1424         obj->dirty = 1;
1425         yaffs_add_obj_to_dir(new_dir, obj);
1426
1427         if (unlink_op)
1428                 obj->unlinked = 1;
1429
1430         /* If it is a deletion then we mark it as a shrink for gc  */
1431         if (yaffs_update_oh(obj, new_name, 0, del_op, shadows, NULL) >= 0)
1432                 return YAFFS_OK;
1433
1434         return YAFFS_FAIL;
1435 }
1436
1437 /*------------------------ Short Operations Cache ------------------------------
1438  *   In many situations where there is no high level buffering  a lot of
1439  *   reads might be short sequential reads, and a lot of writes may be short
1440  *   sequential writes. eg. scanning/writing a jpeg file.
1441  *   In these cases, a short read/write cache can provide a huge perfomance
1442  *   benefit with dumb-as-a-rock code.
1443  *   In Linux, the page cache provides read buffering and the short op cache
1444  *   provides write buffering.
1445  *
1446  *   There are a small number (~10) of cache chunks per device so that we don't
1447  *   need a very intelligent search.
1448  */
1449
1450 static int yaffs_obj_cache_dirty(struct yaffs_obj *obj)
1451 {
1452         struct yaffs_dev *dev = obj->my_dev;
1453         int i;
1454         struct yaffs_cache *cache;
1455         int n_caches = obj->my_dev->param.n_caches;
1456
1457         for (i = 0; i < n_caches; i++) {
1458                 cache = &dev->cache[i];
1459                 if (cache->object == obj && cache->dirty)
1460                         return 1;
1461         }
1462
1463         return 0;
1464 }
1465
1466 static void yaffs_flush_single_cache(struct yaffs_cache *cache, int discard)
1467 {
1468
1469         if (!cache || cache->locked)
1470                 return;
1471
1472         /* Write it out and free it up  if need be.*/
1473         if (cache->dirty) {
1474                 yaffs_wr_data_obj(cache->object,
1475                                   cache->chunk_id,
1476                                   cache->data,
1477                                   cache->n_bytes,
1478                                   1);
1479
1480                 cache->dirty = 0;
1481         }
1482
1483         if (discard)
1484                 cache->object = NULL;
1485 }
1486
1487 static void yaffs_flush_file_cache(struct yaffs_obj *obj, int discard)
1488 {
1489         struct yaffs_dev *dev = obj->my_dev;
1490         int i;
1491         struct yaffs_cache *cache;
1492         int n_caches = obj->my_dev->param.n_caches;
1493
1494         if (n_caches < 1)
1495                 return;
1496
1497
1498         /* Find the chunks for this object and flush them. */
1499         for (i = 0; i < n_caches; i++) {
1500                 cache = &dev->cache[i];
1501                 if (cache->object == obj)
1502                         yaffs_flush_single_cache(cache, discard);
1503         }
1504
1505 }
1506
1507
1508 void yaffs_flush_whole_cache(struct yaffs_dev *dev, int discard)
1509 {
1510         struct yaffs_obj *obj;
1511         int n_caches = dev->param.n_caches;
1512         int i;
1513
1514         /* Find a dirty object in the cache and flush it...
1515          * until there are no further dirty objects.
1516          */
1517         do {
1518                 obj = NULL;
1519                 for (i = 0; i < n_caches && !obj; i++) {
1520                         if (dev->cache[i].object && dev->cache[i].dirty)
1521                                 obj = dev->cache[i].object;
1522                 }
1523                 if (obj)
1524                         yaffs_flush_file_cache(obj, discard);
1525         } while (obj);
1526
1527 }
1528
1529 /* Grab us an unused cache chunk for use.
1530  * First look for an empty one.
1531  * Then look for the least recently used non-dirty one.
1532  * Then look for the least recently used dirty one...., flush and look again.
1533  */
1534 static struct yaffs_cache *yaffs_grab_chunk_worker(struct yaffs_dev *dev)
1535 {
1536         int i;
1537
1538         if (dev->param.n_caches > 0) {
1539                 for (i = 0; i < dev->param.n_caches; i++) {
1540                         if (!dev->cache[i].object)
1541                                 return &dev->cache[i];
1542                 }
1543         }
1544
1545         return NULL;
1546 }
1547
1548 static struct yaffs_cache *yaffs_grab_chunk_cache(struct yaffs_dev *dev)
1549 {
1550         struct yaffs_cache *cache;
1551         int usage;
1552         int i;
1553
1554         if (dev->param.n_caches < 1)
1555                 return NULL;
1556
1557         /* First look for an unused cache */
1558
1559         cache = yaffs_grab_chunk_worker(dev);
1560
1561         if (cache)
1562                 return cache;
1563
1564         /*
1565          * Thery were all in use.
1566          * Find the LRU cache and flush it if it is dirty.
1567          */
1568
1569         usage = -1;
1570         cache = NULL;
1571
1572         for (i = 0; i < dev->param.n_caches; i++) {
1573                 if (dev->cache[i].object &&
1574                     !dev->cache[i].locked &&
1575                     (dev->cache[i].last_use < usage || !cache)) {
1576                                 usage = dev->cache[i].last_use;
1577                                 cache = &dev->cache[i];
1578                 }
1579         }
1580
1581 #if 1
1582         yaffs_flush_single_cache(cache, 1);
1583 #else
1584         yaffs_flush_file_cache(cache->object, 1);
1585         cache = yaffs_grab_chunk_worker(dev);
1586 #endif
1587
1588         return cache;
1589 }
1590
1591 /* Find a cached chunk */
1592 static struct yaffs_cache *yaffs_find_chunk_cache(const struct yaffs_obj *obj,
1593                                                   int chunk_id)
1594 {
1595         struct yaffs_dev *dev = obj->my_dev;
1596         int i;
1597
1598         if (dev->param.n_caches < 1)
1599                 return NULL;
1600
1601         for (i = 0; i < dev->param.n_caches; i++) {
1602                 if (dev->cache[i].object == obj &&
1603                     dev->cache[i].chunk_id == chunk_id) {
1604                         dev->cache_hits++;
1605
1606                         return &dev->cache[i];
1607                 }
1608         }
1609         return NULL;
1610 }
1611
1612 /* Mark the chunk for the least recently used algorithym */
1613 static void yaffs_use_cache(struct yaffs_dev *dev, struct yaffs_cache *cache,
1614                             int is_write)
1615 {
1616         int i;
1617
1618         if (dev->param.n_caches < 1)
1619                 return;
1620
1621         if (dev->cache_last_use < 0 ||
1622                 dev->cache_last_use > 100000000) {
1623                 /* Reset the cache usages */
1624                 for (i = 1; i < dev->param.n_caches; i++)
1625                         dev->cache[i].last_use = 0;
1626
1627                 dev->cache_last_use = 0;
1628         }
1629         dev->cache_last_use++;
1630         cache->last_use = dev->cache_last_use;
1631
1632         if (is_write)
1633                 cache->dirty = 1;
1634 }
1635
1636 /* Invalidate a single cache page.
1637  * Do this when a whole page gets written,
1638  * ie the short cache for this page is no longer valid.
1639  */
1640 static void yaffs_invalidate_chunk_cache(struct yaffs_obj *object, int chunk_id)
1641 {
1642         struct yaffs_cache *cache;
1643
1644         if (object->my_dev->param.n_caches > 0) {
1645                 cache = yaffs_find_chunk_cache(object, chunk_id);
1646
1647                 if (cache)
1648                         cache->object = NULL;
1649         }
1650 }
1651
1652 /* Invalidate all the cache pages associated with this object
1653  * Do this whenever ther file is deleted or resized.
1654  */
1655 static void yaffs_invalidate_whole_cache(struct yaffs_obj *in)
1656 {
1657         int i;
1658         struct yaffs_dev *dev = in->my_dev;
1659
1660         if (dev->param.n_caches > 0) {
1661                 /* Invalidate it. */
1662                 for (i = 0; i < dev->param.n_caches; i++) {
1663                         if (dev->cache[i].object == in)
1664                                 dev->cache[i].object = NULL;
1665                 }
1666         }
1667 }
1668
1669 static void yaffs_unhash_obj(struct yaffs_obj *obj)
1670 {
1671         int bucket;
1672         struct yaffs_dev *dev = obj->my_dev;
1673
1674         /* If it is still linked into the bucket list, free from the list */
1675         if (!list_empty(&obj->hash_link)) {
1676                 list_del_init(&obj->hash_link);
1677                 bucket = yaffs_hash_fn(obj->obj_id);
1678                 dev->obj_bucket[bucket].count--;
1679         }
1680 }
1681
1682 /*  FreeObject frees up a Object and puts it back on the free list */
1683 static void yaffs_free_obj(struct yaffs_obj *obj)
1684 {
1685         struct yaffs_dev *dev;
1686
1687         if (!obj) {
1688                 BUG();
1689                 return;
1690         }
1691         dev = obj->my_dev;
1692         yaffs_trace(YAFFS_TRACE_OS, "FreeObject %p inode %p",
1693                 obj, obj->my_inode);
1694         if (obj->parent)
1695                 BUG();
1696         if (!list_empty(&obj->siblings))
1697                 BUG();
1698
1699         if (obj->my_inode) {
1700                 /* We're still hooked up to a cached inode.
1701                  * Don't delete now, but mark for later deletion
1702                  */
1703                 obj->defered_free = 1;
1704                 return;
1705         }
1706
1707         yaffs_unhash_obj(obj);
1708
1709         yaffs_free_raw_obj(dev, obj);
1710         dev->n_obj--;
1711         dev->checkpoint_blocks_required = 0;    /* force recalculation */
1712 }
1713
1714 void yaffs_handle_defered_free(struct yaffs_obj *obj)
1715 {
1716         if (obj->defered_free)
1717                 yaffs_free_obj(obj);
1718 }
1719
1720 static int yaffs_generic_obj_del(struct yaffs_obj *in)
1721 {
1722         /* Iinvalidate the file's data in the cache, without flushing. */
1723         yaffs_invalidate_whole_cache(in);
1724
1725         if (in->my_dev->param.is_yaffs2 && in->parent != in->my_dev->del_dir) {
1726                 /* Move to unlinked directory so we have a deletion record */
1727                 yaffs_change_obj_name(in, in->my_dev->del_dir, _Y("deleted"), 0,
1728                                       0);
1729         }
1730
1731         yaffs_remove_obj_from_dir(in);
1732         yaffs_chunk_del(in->my_dev, in->hdr_chunk, 1, __LINE__);
1733         in->hdr_chunk = 0;
1734
1735         yaffs_free_obj(in);
1736         return YAFFS_OK;
1737
1738 }
1739
1740 static void yaffs_soft_del_file(struct yaffs_obj *obj)
1741 {
1742         if (!obj->deleted ||
1743             obj->variant_type != YAFFS_OBJECT_TYPE_FILE ||
1744             obj->soft_del)
1745                 return;
1746
1747         if (obj->n_data_chunks <= 0) {
1748                 /* Empty file with no duplicate object headers,
1749                  * just delete it immediately */
1750                 yaffs_free_tnode(obj->my_dev, obj->variant.file_variant.top);
1751                 obj->variant.file_variant.top = NULL;
1752                 yaffs_trace(YAFFS_TRACE_TRACING,
1753                         "yaffs: Deleting empty file %d",
1754                         obj->obj_id);
1755                 yaffs_generic_obj_del(obj);
1756         } else {
1757                 yaffs_soft_del_worker(obj,
1758                                       obj->variant.file_variant.top,
1759                                       obj->variant.
1760                                       file_variant.top_level, 0);
1761                 obj->soft_del = 1;
1762         }
1763 }
1764
1765 /* Pruning removes any part of the file structure tree that is beyond the
1766  * bounds of the file (ie that does not point to chunks).
1767  *
1768  * A file should only get pruned when its size is reduced.
1769  *
1770  * Before pruning, the chunks must be pulled from the tree and the
1771  * level 0 tnode entries must be zeroed out.
1772  * Could also use this for file deletion, but that's probably better handled
1773  * by a special case.
1774  *
1775  * This function is recursive. For levels > 0 the function is called again on
1776  * any sub-tree. For level == 0 we just check if the sub-tree has data.
1777  * If there is no data in a subtree then it is pruned.
1778  */
1779
1780 static struct yaffs_tnode *yaffs_prune_worker(struct yaffs_dev *dev,
1781                                               struct yaffs_tnode *tn, u32 level,
1782                                               int del0)
1783 {
1784         int i;
1785         int has_data;
1786
1787         if (!tn)
1788                 return tn;
1789
1790         has_data = 0;
1791
1792         if (level > 0) {
1793                 for (i = 0; i < YAFFS_NTNODES_INTERNAL; i++) {
1794                         if (tn->internal[i]) {
1795                                 tn->internal[i] =
1796                                     yaffs_prune_worker(dev,
1797                                                 tn->internal[i],
1798                                                 level - 1,
1799                                                 (i == 0) ? del0 : 1);
1800                         }
1801
1802                         if (tn->internal[i])
1803                                 has_data++;
1804                 }
1805         } else {
1806                 int tnode_size_u32 = dev->tnode_size / sizeof(u32);
1807                 u32 *map = (u32 *) tn;
1808
1809                 for (i = 0; !has_data && i < tnode_size_u32; i++) {
1810                         if (map[i])
1811                                 has_data++;
1812                 }
1813         }
1814
1815         if (has_data == 0 && del0) {
1816                 /* Free and return NULL */
1817                 yaffs_free_tnode(dev, tn);
1818                 tn = NULL;
1819         }
1820         return tn;
1821 }
1822
1823 static int yaffs_prune_tree(struct yaffs_dev *dev,
1824                             struct yaffs_file_var *file_struct)
1825 {
1826         int i;
1827         int has_data;
1828         int done = 0;
1829         struct yaffs_tnode *tn;
1830
1831         if (file_struct->top_level < 1)
1832                 return YAFFS_OK;
1833
1834         file_struct->top =
1835            yaffs_prune_worker(dev, file_struct->top, file_struct->top_level, 0);
1836
1837         /* Now we have a tree with all the non-zero branches NULL but
1838          * the height is the same as it was.
1839          * Let's see if we can trim internal tnodes to shorten the tree.
1840          * We can do this if only the 0th element in the tnode is in use
1841          * (ie all the non-zero are NULL)
1842          */
1843
1844         while (file_struct->top_level && !done) {
1845                 tn = file_struct->top;
1846
1847                 has_data = 0;
1848                 for (i = 1; i < YAFFS_NTNODES_INTERNAL; i++) {
1849                         if (tn->internal[i])
1850                                 has_data++;
1851                 }
1852
1853                 if (!has_data) {
1854                         file_struct->top = tn->internal[0];
1855                         file_struct->top_level--;
1856                         yaffs_free_tnode(dev, tn);
1857                 } else {
1858                         done = 1;
1859                 }
1860         }
1861
1862         return YAFFS_OK;
1863 }
1864
1865 /*-------------------- End of File Structure functions.-------------------*/
1866
1867 /* alloc_empty_obj gets us a clean Object.*/
1868 static struct yaffs_obj *yaffs_alloc_empty_obj(struct yaffs_dev *dev)
1869 {
1870         struct yaffs_obj *obj = yaffs_alloc_raw_obj(dev);
1871
1872         if (!obj)
1873                 return obj;
1874
1875         dev->n_obj++;
1876
1877         /* Now sweeten it up... */
1878
1879         memset(obj, 0, sizeof(struct yaffs_obj));
1880         obj->being_created = 1;
1881
1882         obj->my_dev = dev;
1883         obj->hdr_chunk = 0;
1884         obj->variant_type = YAFFS_OBJECT_TYPE_UNKNOWN;
1885         INIT_LIST_HEAD(&(obj->hard_links));
1886         INIT_LIST_HEAD(&(obj->hash_link));
1887         INIT_LIST_HEAD(&obj->siblings);
1888
1889         /* Now make the directory sane */
1890         if (dev->root_dir) {
1891                 obj->parent = dev->root_dir;
1892                 list_add(&(obj->siblings),
1893                          &dev->root_dir->variant.dir_variant.children);
1894         }
1895
1896         /* Add it to the lost and found directory.
1897          * NB Can't put root or lost-n-found in lost-n-found so
1898          * check if lost-n-found exists first
1899          */
1900         if (dev->lost_n_found)
1901                 yaffs_add_obj_to_dir(dev->lost_n_found, obj);
1902
1903         obj->being_created = 0;
1904
1905         dev->checkpoint_blocks_required = 0;    /* force recalculation */
1906
1907         return obj;
1908 }
1909
1910 static int yaffs_find_nice_bucket(struct yaffs_dev *dev)
1911 {
1912         int i;
1913         int l = 999;
1914         int lowest = 999999;
1915
1916         /* Search for the shortest list or one that
1917          * isn't too long.
1918          */
1919
1920         for (i = 0; i < 10 && lowest > 4; i++) {
1921                 dev->bucket_finder++;
1922                 dev->bucket_finder %= YAFFS_NOBJECT_BUCKETS;
1923                 if (dev->obj_bucket[dev->bucket_finder].count < lowest) {
1924                         lowest = dev->obj_bucket[dev->bucket_finder].count;
1925                         l = dev->bucket_finder;
1926                 }
1927         }
1928
1929         return l;
1930 }
1931
1932 static int yaffs_new_obj_id(struct yaffs_dev *dev)
1933 {
1934         int bucket = yaffs_find_nice_bucket(dev);
1935         int found = 0;
1936         struct list_head *i;
1937         u32 n = (u32) bucket;
1938
1939         /* Now find an object value that has not already been taken
1940          * by scanning the list.
1941          */
1942
1943         while (!found) {
1944                 found = 1;
1945                 n += YAFFS_NOBJECT_BUCKETS;
1946                 if (1 || dev->obj_bucket[bucket].count > 0) {
1947                         list_for_each(i, &dev->obj_bucket[bucket].list) {
1948                                 /* If there is already one in the list */
1949                                 if (i && list_entry(i, struct yaffs_obj,
1950                                                     hash_link)->obj_id == n) {
1951                                         found = 0;
1952                                 }
1953                         }
1954                 }
1955         }
1956         return n;
1957 }
1958
1959 static void yaffs_hash_obj(struct yaffs_obj *in)
1960 {
1961         int bucket = yaffs_hash_fn(in->obj_id);
1962         struct yaffs_dev *dev = in->my_dev;
1963
1964         list_add(&in->hash_link, &dev->obj_bucket[bucket].list);
1965         dev->obj_bucket[bucket].count++;
1966 }
1967
1968 struct yaffs_obj *yaffs_find_by_number(struct yaffs_dev *dev, u32 number)
1969 {
1970         int bucket = yaffs_hash_fn(number);
1971         struct list_head *i;
1972         struct yaffs_obj *in;
1973
1974         list_for_each(i, &dev->obj_bucket[bucket].list) {
1975                 /* Look if it is in the list */
1976                 in = list_entry(i, struct yaffs_obj, hash_link);
1977                 if (in->obj_id == number) {
1978                         /* Don't show if it is defered free */
1979                         if (in->defered_free)
1980                                 return NULL;
1981                         return in;
1982                 }
1983         }
1984
1985         return NULL;
1986 }
1987
1988 static struct yaffs_obj *yaffs_new_obj(struct yaffs_dev *dev, int number,
1989                                 enum yaffs_obj_type type)
1990 {
1991         struct yaffs_obj *the_obj = NULL;
1992         struct yaffs_tnode *tn = NULL;
1993
1994         if (number < 0)
1995                 number = yaffs_new_obj_id(dev);
1996
1997         if (type == YAFFS_OBJECT_TYPE_FILE) {
1998                 tn = yaffs_get_tnode(dev);
1999                 if (!tn)
2000                         return NULL;
2001         }
2002
2003         the_obj = yaffs_alloc_empty_obj(dev);
2004         if (!the_obj) {
2005                 if (tn)
2006                         yaffs_free_tnode(dev, tn);
2007                 return NULL;
2008         }
2009
2010         the_obj->fake = 0;
2011         the_obj->rename_allowed = 1;
2012         the_obj->unlink_allowed = 1;
2013         the_obj->obj_id = number;
2014         yaffs_hash_obj(the_obj);
2015         the_obj->variant_type = type;
2016         yaffs_load_current_time(the_obj, 1, 1);
2017
2018         switch (type) {
2019         case YAFFS_OBJECT_TYPE_FILE:
2020                 the_obj->variant.file_variant.file_size = 0;
2021                 the_obj->variant.file_variant.scanned_size = 0;
2022                 the_obj->variant.file_variant.shrink_size =
2023                                                 yaffs_max_file_size(dev);
2024                 the_obj->variant.file_variant.top_level = 0;
2025                 the_obj->variant.file_variant.top = tn;
2026                 break;
2027         case YAFFS_OBJECT_TYPE_DIRECTORY:
2028                 INIT_LIST_HEAD(&the_obj->variant.dir_variant.children);
2029                 INIT_LIST_HEAD(&the_obj->variant.dir_variant.dirty);
2030                 break;
2031         case YAFFS_OBJECT_TYPE_SYMLINK:
2032         case YAFFS_OBJECT_TYPE_HARDLINK:
2033         case YAFFS_OBJECT_TYPE_SPECIAL:
2034                 /* No action required */
2035                 break;
2036         case YAFFS_OBJECT_TYPE_UNKNOWN:
2037                 /* todo this should not happen */
2038                 break;
2039         }
2040         return the_obj;
2041 }
2042
2043 static struct yaffs_obj *yaffs_create_fake_dir(struct yaffs_dev *dev,
2044                                                int number, u32 mode)
2045 {
2046
2047         struct yaffs_obj *obj =
2048             yaffs_new_obj(dev, number, YAFFS_OBJECT_TYPE_DIRECTORY);
2049
2050         if (!obj)
2051                 return NULL;
2052
2053         obj->fake = 1;  /* it is fake so it might not use NAND */
2054         obj->rename_allowed = 0;
2055         obj->unlink_allowed = 0;
2056         obj->deleted = 0;
2057         obj->unlinked = 0;
2058         obj->yst_mode = mode;
2059         obj->my_dev = dev;
2060         obj->hdr_chunk = 0;     /* Not a valid chunk. */
2061         return obj;
2062
2063 }
2064
2065
2066 static void yaffs_init_tnodes_and_objs(struct yaffs_dev *dev)
2067 {
2068         int i;
2069
2070         dev->n_obj = 0;
2071         dev->n_tnodes = 0;
2072         yaffs_init_raw_tnodes_and_objs(dev);
2073
2074         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
2075                 INIT_LIST_HEAD(&dev->obj_bucket[i].list);
2076                 dev->obj_bucket[i].count = 0;
2077         }
2078 }
2079
2080 struct yaffs_obj *yaffs_find_or_create_by_number(struct yaffs_dev *dev,
2081                                                  int number,
2082                                                  enum yaffs_obj_type type)
2083 {
2084         struct yaffs_obj *the_obj = NULL;
2085
2086         if (number > 0)
2087                 the_obj = yaffs_find_by_number(dev, number);
2088
2089         if (!the_obj)
2090                 the_obj = yaffs_new_obj(dev, number, type);
2091
2092         return the_obj;
2093
2094 }
2095
2096 YCHAR *yaffs_clone_str(const YCHAR *str)
2097 {
2098         YCHAR *new_str = NULL;
2099         int len;
2100
2101         if (!str)
2102                 str = _Y("");
2103
2104         len = yaffs_strnlen(str, YAFFS_MAX_ALIAS_LENGTH);
2105         new_str = kmalloc((len + 1) * sizeof(YCHAR), GFP_NOFS);
2106         if (new_str) {
2107                 yaffs_strncpy(new_str, str, len);
2108                 new_str[len] = 0;
2109         }
2110         return new_str;
2111
2112 }
2113 /*
2114  *yaffs_update_parent() handles fixing a directories mtime and ctime when a new
2115  * link (ie. name) is created or deleted in the directory.
2116  *
2117  * ie.
2118  *   create dir/a : update dir's mtime/ctime
2119  *   rm dir/a:   update dir's mtime/ctime
2120  *   modify dir/a: don't update dir's mtimme/ctime
2121  *
2122  * This can be handled immediately or defered. Defering helps reduce the number
2123  * of updates when many files in a directory are changed within a brief period.
2124  *
2125  * If the directory updating is defered then yaffs_update_dirty_dirs must be
2126  * called periodically.
2127  */
2128
2129 static void yaffs_update_parent(struct yaffs_obj *obj)
2130 {
2131         struct yaffs_dev *dev;
2132
2133         if (!obj)
2134                 return;
2135         dev = obj->my_dev;
2136         obj->dirty = 1;
2137         yaffs_load_current_time(obj, 0, 1);
2138         if (dev->param.defered_dir_update) {
2139                 struct list_head *link = &obj->variant.dir_variant.dirty;
2140
2141                 if (list_empty(link)) {
2142                         list_add(link, &dev->dirty_dirs);
2143                         yaffs_trace(YAFFS_TRACE_BACKGROUND,
2144                           "Added object %d to dirty directories",
2145                            obj->obj_id);
2146                 }
2147
2148         } else {
2149                 yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
2150         }
2151 }
2152
2153 void yaffs_update_dirty_dirs(struct yaffs_dev *dev)
2154 {
2155         struct list_head *link;
2156         struct yaffs_obj *obj;
2157         struct yaffs_dir_var *d_s;
2158         union yaffs_obj_var *o_v;
2159
2160         yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update dirty directories");
2161
2162         while (!list_empty(&dev->dirty_dirs)) {
2163                 link = dev->dirty_dirs.next;
2164                 list_del_init(link);
2165
2166                 d_s = list_entry(link, struct yaffs_dir_var, dirty);
2167                 o_v = list_entry(d_s, union yaffs_obj_var, dir_variant);
2168                 obj = list_entry(o_v, struct yaffs_obj, variant);
2169
2170                 yaffs_trace(YAFFS_TRACE_BACKGROUND, "Update directory %d",
2171                         obj->obj_id);
2172
2173                 if (obj->dirty)
2174                         yaffs_update_oh(obj, NULL, 0, 0, 0, NULL);
2175         }
2176 }
2177
2178 /*
2179  * Mknod (create) a new object.
2180  * equiv_obj only has meaning for a hard link;
2181  * alias_str only has meaning for a symlink.
2182  * rdev only has meaning for devices (a subset of special objects)
2183  */
2184
2185 static struct yaffs_obj *yaffs_create_obj(enum yaffs_obj_type type,
2186                                           struct yaffs_obj *parent,
2187                                           const YCHAR *name,
2188                                           u32 mode,
2189                                           u32 uid,
2190                                           u32 gid,
2191                                           struct yaffs_obj *equiv_obj,
2192                                           const YCHAR *alias_str, u32 rdev)
2193 {
2194         struct yaffs_obj *in;
2195         YCHAR *str = NULL;
2196         struct yaffs_dev *dev = parent->my_dev;
2197
2198         /* Check if the entry exists.
2199          * If it does then fail the call since we don't want a dup. */
2200         if (yaffs_find_by_name(parent, name))
2201                 return NULL;
2202
2203         if (type == YAFFS_OBJECT_TYPE_SYMLINK) {
2204                 str = yaffs_clone_str(alias_str);
2205                 if (!str)
2206                         return NULL;
2207         }
2208
2209         in = yaffs_new_obj(dev, -1, type);
2210
2211         if (!in) {
2212                 kfree(str);
2213                 return NULL;
2214         }
2215
2216         in->hdr_chunk = 0;
2217         in->valid = 1;
2218         in->variant_type = type;
2219
2220         in->yst_mode = mode;
2221
2222         yaffs_attribs_init(in, gid, uid, rdev);
2223
2224         in->n_data_chunks = 0;
2225
2226         yaffs_set_obj_name(in, name);
2227         in->dirty = 1;
2228
2229         yaffs_add_obj_to_dir(parent, in);
2230
2231         in->my_dev = parent->my_dev;
2232
2233         switch (type) {
2234         case YAFFS_OBJECT_TYPE_SYMLINK:
2235                 in->variant.symlink_variant.alias = str;
2236                 break;
2237         case YAFFS_OBJECT_TYPE_HARDLINK:
2238                 in->variant.hardlink_variant.equiv_obj = equiv_obj;
2239                 in->variant.hardlink_variant.equiv_id = equiv_obj->obj_id;
2240                 list_add(&in->hard_links, &equiv_obj->hard_links);
2241                 break;
2242         case YAFFS_OBJECT_TYPE_FILE:
2243         case YAFFS_OBJECT_TYPE_DIRECTORY:
2244         case YAFFS_OBJECT_TYPE_SPECIAL:
2245         case YAFFS_OBJECT_TYPE_UNKNOWN:
2246                 /* do nothing */
2247                 break;
2248         }
2249
2250         if (yaffs_update_oh(in, name, 0, 0, 0, NULL) < 0) {
2251                 /* Could not create the object header, fail */
2252                 yaffs_del_obj(in);
2253                 in = NULL;
2254         }
2255
2256         if (in)
2257                 yaffs_update_parent(parent);
2258
2259         return in;
2260 }
2261
2262 struct yaffs_obj *yaffs_create_file(struct yaffs_obj *parent,
2263                                     const YCHAR *name, u32 mode, u32 uid,
2264                                     u32 gid)
2265 {
2266         return yaffs_create_obj(YAFFS_OBJECT_TYPE_FILE, parent, name, mode,
2267                                 uid, gid, NULL, NULL, 0);
2268 }
2269
2270 struct yaffs_obj *yaffs_create_dir(struct yaffs_obj *parent, const YCHAR *name,
2271                                    u32 mode, u32 uid, u32 gid)
2272 {
2273         return yaffs_create_obj(YAFFS_OBJECT_TYPE_DIRECTORY, parent, name,
2274                                 mode, uid, gid, NULL, NULL, 0);
2275 }
2276
2277 struct yaffs_obj *yaffs_create_special(struct yaffs_obj *parent,
2278                                        const YCHAR *name, u32 mode, u32 uid,
2279                                        u32 gid, u32 rdev)
2280 {
2281         return yaffs_create_obj(YAFFS_OBJECT_TYPE_SPECIAL, parent, name, mode,
2282                                 uid, gid, NULL, NULL, rdev);
2283 }
2284
2285 struct yaffs_obj *yaffs_create_symlink(struct yaffs_obj *parent,
2286                                        const YCHAR *name, u32 mode, u32 uid,
2287                                        u32 gid, const YCHAR *alias)
2288 {
2289         return yaffs_create_obj(YAFFS_OBJECT_TYPE_SYMLINK, parent, name, mode,
2290                                 uid, gid, NULL, alias, 0);
2291 }
2292
2293 /* yaffs_link_obj returns the object id of the equivalent object.*/
2294 struct yaffs_obj *yaffs_link_obj(struct yaffs_obj *parent, const YCHAR * name,
2295                                  struct yaffs_obj *equiv_obj)
2296 {
2297         /* Get the real object in case we were fed a hard link obj */
2298         equiv_obj = yaffs_get_equivalent_obj(equiv_obj);
2299
2300         if (yaffs_create_obj(YAFFS_OBJECT_TYPE_HARDLINK,
2301                         parent, name, 0, 0, 0,
2302                         equiv_obj, NULL, 0))
2303                 return equiv_obj;
2304
2305         return NULL;
2306
2307 }
2308
2309
2310
2311 /*---------------------- Block Management and Page Allocation -------------*/
2312
2313 static void yaffs_deinit_blocks(struct yaffs_dev *dev)
2314 {
2315         if (dev->block_info_alt && dev->block_info)
2316                 vfree(dev->block_info);
2317         else
2318                 kfree(dev->block_info);
2319
2320         dev->block_info_alt = 0;
2321
2322         dev->block_info = NULL;
2323
2324         if (dev->chunk_bits_alt && dev->chunk_bits)
2325                 vfree(dev->chunk_bits);
2326         else
2327                 kfree(dev->chunk_bits);
2328         dev->chunk_bits_alt = 0;
2329         dev->chunk_bits = NULL;
2330 }
2331
2332 static int yaffs_init_blocks(struct yaffs_dev *dev)
2333 {
2334         int n_blocks = dev->internal_end_block - dev->internal_start_block + 1;
2335
2336         dev->block_info = NULL;
2337         dev->chunk_bits = NULL;
2338         dev->alloc_block = -1;  /* force it to get a new one */
2339
2340         /* If the first allocation strategy fails, thry the alternate one */
2341         dev->block_info =
2342                 kmalloc(n_blocks * sizeof(struct yaffs_block_info), GFP_NOFS);
2343         if (!dev->block_info) {
2344                 dev->block_info =
2345                     vmalloc(n_blocks * sizeof(struct yaffs_block_info));
2346                 dev->block_info_alt = 1;
2347         } else {
2348                 dev->block_info_alt = 0;
2349         }
2350
2351         if (!dev->block_info)
2352                 goto alloc_error;
2353
2354         /* Set up dynamic blockinfo stuff. Round up bytes. */
2355         dev->chunk_bit_stride = (dev->param.chunks_per_block + 7) / 8;
2356         dev->chunk_bits =
2357                 kmalloc(dev->chunk_bit_stride * n_blocks, GFP_NOFS);
2358         if (!dev->chunk_bits) {
2359                 dev->chunk_bits =
2360                     vmalloc(dev->chunk_bit_stride * n_blocks);
2361                 dev->chunk_bits_alt = 1;
2362         } else {
2363                 dev->chunk_bits_alt = 0;
2364         }
2365         if (!dev->chunk_bits)
2366                 goto alloc_error;
2367
2368
2369         memset(dev->block_info, 0, n_blocks * sizeof(struct yaffs_block_info));
2370         memset(dev->chunk_bits, 0, dev->chunk_bit_stride * n_blocks);
2371         return YAFFS_OK;
2372
2373 alloc_error:
2374         yaffs_deinit_blocks(dev);
2375         return YAFFS_FAIL;
2376 }
2377
2378
2379 void yaffs_block_became_dirty(struct yaffs_dev *dev, int block_no)
2380 {
2381         struct yaffs_block_info *bi = yaffs_get_block_info(dev, block_no);
2382         int erased_ok = 0;
2383         int i;
2384
2385         /* If the block is still healthy erase it and mark as clean.
2386          * If the block has had a data failure, then retire it.
2387          */
2388
2389         yaffs_trace(YAFFS_TRACE_GC | YAFFS_TRACE_ERASE,
2390                 "yaffs_block_became_dirty block %d state %d %s",
2391                 block_no, bi->block_state,
2392                 (bi->needs_retiring) ? "needs retiring" : "");
2393
2394         yaffs2_clear_oldest_dirty_seq(dev, bi);
2395
2396         bi->block_state = YAFFS_BLOCK_STATE_DIRTY;
2397
2398         /* If this is the block being garbage collected then stop gc'ing */
2399         if ((u32)block_no == dev->gc_block)
2400                 dev->gc_block = 0;
2401
2402         /* If this block is currently the best candidate for gc
2403          * then drop as a candidate */
2404         if ((u32)block_no == dev->gc_dirtiest) {
2405                 dev->gc_dirtiest = 0;
2406                 dev->gc_pages_in_use = 0;
2407         }
2408
2409         if (!bi->needs_retiring) {
2410                 yaffs2_checkpt_invalidate(dev);
2411                 erased_ok = yaffs_erase_block(dev, block_no);
2412                 if (!erased_ok) {
2413                         dev->n_erase_failures++;
2414                         yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2415                           "**>> Erasure failed %d", block_no);
2416                 }
2417         }
2418
2419         /* Verify erasure if needed */
2420         if (erased_ok &&
2421             ((yaffs_trace_mask & YAFFS_TRACE_ERASE) ||
2422              !yaffs_skip_verification(dev))) {
2423                 for (i = 0; i < dev->param.chunks_per_block; i++) {
2424                         if (!yaffs_check_chunk_erased(dev,
2425                                 block_no * dev->param.chunks_per_block + i)) {
2426                                 yaffs_trace(YAFFS_TRACE_ERROR,
2427                                         ">>Block %d erasure supposedly OK, but chunk %d not erased",
2428                                         block_no, i);
2429                         }
2430                 }
2431         }
2432
2433         if (!erased_ok) {
2434                 /* We lost a block of free space */
2435                 dev->n_free_chunks -= dev->param.chunks_per_block;
2436                 yaffs_retire_block(dev, block_no);
2437                 yaffs_trace(YAFFS_TRACE_ERROR | YAFFS_TRACE_BAD_BLOCKS,
2438                         "**>> Block %d retired", block_no);
2439                 return;
2440         }
2441
2442         /* Clean it up... */
2443         bi->block_state = YAFFS_BLOCK_STATE_EMPTY;
2444         bi->seq_number = 0;
2445         dev->n_erased_blocks++;
2446         bi->pages_in_use = 0;
2447         bi->soft_del_pages = 0;
2448         bi->has_shrink_hdr = 0;
2449         bi->skip_erased_check = 1;      /* Clean, so no need to check */
2450         bi->gc_prioritise = 0;
2451         bi->has_summary = 0;
2452
2453         yaffs_clear_chunk_bits(dev, block_no);
2454
2455         yaffs_trace(YAFFS_TRACE_ERASE, "Erased block %d", block_no);
2456 }
2457
2458 static inline int yaffs_gc_process_chunk(struct yaffs_dev *dev,
2459                                         struct yaffs_block_info *bi,
2460                                         int old_chunk, u8 *buffer)
2461 {
2462         int new_chunk;
2463         int mark_flash = 1;
2464         struct yaffs_ext_tags tags;
2465         struct yaffs_obj *object;
2466         int matching_chunk;
2467         int ret_val = YAFFS_OK;
2468
2469         memset(&tags, 0, sizeof(tags));
2470         if (!yaffs_rd_chunk_tags_nand(dev, old_chunk,
2471                                  buffer, &tags))
2472
2473         {
2474                 yaffs_trace(YAFFS_TRACE_ERROR, "yaffs_gc_process_chunk: unhandled error from rd_chunk_tags_nand");
2475         }
2476         object = yaffs_find_by_number(dev, tags.obj_id);
2477
2478         yaffs_trace(YAFFS_TRACE_GC_DETAIL,
2479                 "Collecting chunk in block %d, %d %d %d ",
2480                 dev->gc_chunk, tags.obj_id,
2481                 tags.chunk_id, tags.n_bytes);
2482
2483         if (object && !yaffs_skip_verification(dev)) {
2484                 if (tags.chunk_id == 0)
2485                         matching_chunk =
2486                             object->hdr_chunk;
2487                 else if (object->soft_del)
2488                         /* Defeat the test */
2489                         matching_chunk = old_chunk;
2490                 else
2491                         matching_chunk =
2492                             yaffs_find_chunk_in_file
2493                             (object, tags.chunk_id,
2494                              NULL);
2495
2496                 if (old_chunk != matching_chunk)
2497                         yaffs_trace(YAFFS_TRACE_ERROR,
2498                                 "gc: page in gc mismatch: %d %d %d %d",
2499                                 old_chunk,
2500                                 matching_chunk,
2501                                 tags.obj_id,
2502                                 tags.chunk_id);
2503         }
2504
2505         if (!object) {
2506                 yaffs_trace(YAFFS_TRACE_ERROR,
2507                         "page %d in gc has no object: %d %d %d ",
2508                         old_chunk,
2509                         tags.obj_id, tags.chunk_id,
2510                         tags.n_bytes);
2511         }
2512
2513         if (object &&
2514             object->deleted &&
2515             object->soft_del && tags.chunk_id != 0) {
2516                 /* Data chunk in a soft deleted file,
2517                  * throw it away.
2518                  * It's a soft deleted data chunk,
2519                  * No need to copy this, just forget
2520                  * about it and fix up the object.
2521                  */
2522
2523                 /* Free chunks already includes
2524                  * softdeleted chunks, how ever this
2525                  * chunk is going to soon be really
2526                  * deleted which will increment free
2527                  * chunks. We have to decrement free
2528                  * chunks so this works out properly.
2529                  */
2530                 dev->n_free_chunks--;
2531                 bi->soft_del_pages--;
2532
2533                 object->n_data_chunks--;
2534                 if (object->n_data_chunks <= 0) {
2535                         /* remeber to clean up obj */
2536                         dev->gc_cleanup_list[dev->n_clean_ups] = tags.obj_id;
2537                         dev->n_clean_ups++;
2538                 }
2539                 mark_flash = 0;
2540         } else if (object) {
2541                 /* It's either a data chunk in a live
2542                  * file or an ObjectHeader, so we're
2543                  * interested in it.
2544                  * NB Need to keep the ObjectHeaders of
2545                  * deleted files until the whole file
2546                  * has been deleted off
2547                  */
2548                 tags.serial_number++;
2549                 dev->n_gc_copies++;
2550
2551                 if (tags.chunk_id == 0) {
2552                         /* It is an object Id,
2553                          * We need to nuke the
2554                          * shrinkheader flags since its
2555                          * work is done.
2556                          * Also need to clean up
2557                          * shadowing.
2558                          */
2559                         struct yaffs_obj_hdr *oh;
2560                         oh = (struct yaffs_obj_hdr *) buffer;
2561
2562                         oh->is_shrink = 0;
2563                         tags.extra_is_shrink = 0;
2564                         oh->shadows_obj = 0;
2565                         oh->inband_shadowed_obj_id = 0;
2566                         tags.extra_shadows = 0;
2567
2568                         /* Update file size */
2569                         if (object->variant_type == YAFFS_OBJECT_TYPE_FILE) {
2570                                 yaffs_oh_size_load(oh,
2571                                     object->variant.file_variant.file_size);
2572                                 tags.extra_file_size =
2573                                     object->variant.file_variant.file_size;
2574                         }
2575
2576                         yaffs_verify_oh(object, oh, &tags, 1);
2577                         new_chunk =
2578                             yaffs_write_new_chunk(dev, (u8 *) oh, &tags, 1);
2579                 } else {
2580                         new_chunk =
2581                             yaffs_write_new_chunk(dev, buffer, &tags, 1);
2582                 }
2583
2584                 if (new_chunk < 0) {
2585                         ret_val = YAFFS_FAIL;
2586                 } else {
2587
2588                         /* Now fix up the Tnodes etc. */
2589
2590                         if (tags.chunk_id == 0) {
2591                                 /* It's a header */
2592                                 object->hdr_chunk = new_chunk;
2593                                 object->serial = tags.serial_number;
2594                         } else {
2595                                 /* It's a data chunk */
2596                                 yaffs_put_chunk_in_file(object, tags.chunk_id,
2597                                                         new_chunk, 0);
2598                         }
2599                 }
2600         }
2601         if (ret_val == YAFFS_OK)
2602                 yaffs_chunk_del(dev, old_chunk, mark_flash, __LINE__);
2603         return ret_val;
2604 }
2605
2606 static int yaffs_gc_block(struct yaffs_dev *dev, int block, int whole_block)
2607 {
2608         int old_chunk;
2609         int ret_val = YAFFS_OK;
2610         u32 i;
2611         int is_checkpt_block;
2612         int max_copies;
2613         int chunks_before = yaffs_get_erased_chunks(dev);
2614         int chunks_after;
2615         struct yaffs_block_info *bi = yaffs_get_block_info(dev, block);
2616
2617         is_checkpt_block = (bi->block_state == YAFFS_BLOCK_STATE_CHECKPOINT);
2618
2619         yaffs_trace(YAFFS_TRACE_TRACING,
2620                 "Collecting block %d, in use %d, shrink %d, whole_block %d",
2621                 block, bi->pages_in_use, bi->has_shrink_hdr,
2622                 whole_block);
2623
2624         /*yaffs_verify_free_chunks(dev); */
2625
2626         if (bi->block_state == YAFFS_BLOCK_STATE_FULL)
2627                 bi->block_state = YAFFS_BLOCK_STATE_COLLECTING;
2628
2629         bi->has_shrink_hdr = 0; /* clear the flag so that the block can erase */
2630
2631         dev->gc_disable = 1;
2632
2633         yaffs_summary_gc(dev, block);
2634
2635         if (is_checkpt_block || !yaffs_still_some_chunks(dev, block)) {
2636                 yaffs_trace(YAFFS_TRACE_TRACING,
2637                         "Collecting block %d that has no chunks in use",
2638                         block);
2639                 yaffs_block_became_dirty(dev, block);
2640         } else {
2641
2642                 u8 *buffer = yaffs_get_temp_buffer(dev);
2643
2644                 yaffs_verify_blk(dev, bi, block);
2645
2646                 max_copies = (whole_block) ? dev->param.chunks_per_block : 5;
2647                 old_chunk = block * dev->param.chunks_per_block + dev->gc_chunk;
2648
2649                 for (/* init already done */ ;
2650                      ret_val == YAFFS_OK &&
2651                      dev->gc_chunk < (u32)dev->param.chunks_per_block &&
2652                      (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) &&
2653                      max_copies > 0;
2654                      dev->gc_chunk++, old_chunk++) {
2655                         if (yaffs_check_chunk_bit(dev, block, dev->gc_chunk)) {
2656                                 /* Page is in use and might need to be copied */
2657                                 max_copies--;
2658                                 ret_val = yaffs_gc_process_chunk(dev, bi,
2659                                                         old_chunk, buffer);
2660                         }
2661                 }
2662                 yaffs_release_temp_buffer(dev, buffer);
2663         }
2664
2665         yaffs_verify_collected_blk(dev, bi, block);
2666
2667         if (bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
2668                 /*
2669                  * The gc did not complete. Set block state back to FULL
2670                  * because checkpointing does not restore gc.
2671                  */
2672                 bi->block_state = YAFFS_BLOCK_STATE_FULL;
2673         } else {
2674                 /* The gc completed. */
2675                 /* Do any required cleanups */
2676                 for (i = 0; i < dev->n_clean_ups; i++) {
2677                         /* Time to delete the file too */
2678                         struct yaffs_obj *object =
2679                             yaffs_find_by_number(dev, dev->gc_cleanup_list[i]);
2680                         if (object) {
2681                                 yaffs_free_tnode(dev,
2682                                           object->variant.file_variant.top);
2683                                 object->variant.file_variant.top = NULL;
2684                                 yaffs_trace(YAFFS_TRACE_GC,
2685                                         "yaffs: About to finally delete object %d",
2686                                         object->obj_id);
2687                                 yaffs_generic_obj_del(object);
2688                                 object->my_dev->n_deleted_files--;
2689                         }
2690
2691                 }
2692                 chunks_after = yaffs_get_erased_chunks(dev);
2693                 if (chunks_before >= chunks_after)
2694                         yaffs_trace(YAFFS_TRACE_GC,
2695                                 "gc did not increase free chunks before %d after %d",
2696                                 chunks_before, chunks_after);
2697                 dev->gc_block = 0;
2698                 dev->gc_chunk = 0;
2699                 dev->n_clean_ups = 0;
2700         }
2701
2702         dev->gc_disable = 0;
2703
2704         return ret_val;
2705 }
2706
2707 /*
2708  * find_gc_block() selects the dirtiest block (or close enough)
2709  * for garbage collection.
2710  */
2711
2712 static unsigned yaffs_find_gc_block(struct yaffs_dev *dev,
2713                                     int aggressive, int background)
2714 {
2715         int i;
2716         int iterations;
2717         unsigned selected = 0;
2718         int prioritised = 0;
2719         int prioritised_exist = 0;
2720         struct yaffs_block_info *bi;
2721         int threshold;
2722
2723         /* First let's see if we need to grab a prioritised block */
2724         if (dev->has_pending_prioritised_gc && !aggressive) {
2725                 dev->gc_dirtiest = 0;
2726                 bi = dev->block_info;
2727                 for (i = dev->internal_start_block;
2728                      i <= dev->internal_end_block && !selected; i++) {
2729
2730                         if (bi->gc_prioritise) {
2731                                 prioritised_exist = 1;
2732                                 if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2733                                     yaffs_block_ok_for_gc(dev, bi)) {
2734                                         selected = i;
2735                                         prioritised = 1;
2736                                 }
2737                         }
2738                         bi++;
2739                 }
2740
2741                 /*
2742                  * If there is a prioritised block and none was selected then
2743                  * this happened because there is at least one old dirty block
2744                  * gumming up the works. Let's gc the oldest dirty block.
2745                  */
2746
2747                 if (prioritised_exist &&
2748                     !selected && dev->oldest_dirty_block > 0)
2749                         selected = dev->oldest_dirty_block;
2750
2751                 if (!prioritised_exist) /* None found, so we can clear this */
2752                         dev->has_pending_prioritised_gc = 0;
2753         }
2754
2755         /* If we're doing aggressive GC then we are happy to take a less-dirty
2756          * block, and search harder.
2757          * else (leasurely gc), then we only bother to do this if the
2758          * block has only a few pages in use.
2759          */
2760
2761         if (!selected) {
2762                 int pages_used;
2763                 int n_blocks =
2764                     dev->internal_end_block - dev->internal_start_block + 1;
2765                 if (aggressive) {
2766                         threshold = dev->param.chunks_per_block;
2767                         iterations = n_blocks;
2768                 } else {
2769                         int max_threshold;
2770
2771                         if (background)
2772                                 max_threshold = dev->param.chunks_per_block / 2;
2773                         else
2774                                 max_threshold = dev->param.chunks_per_block / 8;
2775
2776                         if (max_threshold < YAFFS_GC_PASSIVE_THRESHOLD)
2777                                 max_threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2778
2779                         threshold = background ? (dev->gc_not_done + 2) * 2 : 0;
2780                         if (threshold < YAFFS_GC_PASSIVE_THRESHOLD)
2781                                 threshold = YAFFS_GC_PASSIVE_THRESHOLD;
2782                         if (threshold > max_threshold)
2783                                 threshold = max_threshold;
2784
2785                         iterations = n_blocks / 16 + 1;
2786                         if (iterations > 100)
2787                                 iterations = 100;
2788                 }
2789
2790                 for (i = 0;
2791                      i < iterations &&
2792                      (dev->gc_dirtiest < 1 ||
2793                       dev->gc_pages_in_use > YAFFS_GC_GOOD_ENOUGH);
2794                      i++) {
2795                         dev->gc_block_finder++;
2796                         if (dev->gc_block_finder < (u32)dev->internal_start_block ||
2797                             (int)dev->gc_block_finder > dev->internal_end_block)
2798                                 dev->gc_block_finder =
2799                                     dev->internal_start_block;
2800
2801                         bi = yaffs_get_block_info(dev, dev->gc_block_finder);
2802
2803                         pages_used = bi->pages_in_use - bi->soft_del_pages;
2804
2805                         if (bi->block_state == YAFFS_BLOCK_STATE_FULL &&
2806                             pages_used < dev->param.chunks_per_block &&
2807                             (dev->gc_dirtiest < 1 ||
2808                              pages_used < (int)dev->gc_pages_in_use) &&
2809                             yaffs_block_ok_for_gc(dev, bi)) {
2810                                 dev->gc_dirtiest = dev->gc_block_finder;
2811                                 dev->gc_pages_in_use = pages_used;
2812                         }
2813                 }
2814
2815                 if (dev->gc_dirtiest > 0 && dev->gc_pages_in_use <= (u32)threshold)
2816                         selected = dev->gc_dirtiest;
2817         }
2818
2819         /*
2820          * If nothing has been selected for a while, try the oldest dirty
2821          * because that's gumming up the works.
2822          */
2823
2824         if (!selected && dev->param.is_yaffs2 &&
2825             dev->gc_not_done >= (background ? 10 : 20)) {
2826                 yaffs2_find_oldest_dirty_seq(dev);
2827                 if (dev->oldest_dirty_block > 0) {
2828                         selected = dev->oldest_dirty_block;
2829                         dev->gc_dirtiest = selected;
2830                         dev->oldest_dirty_gc_count++;
2831                         bi = yaffs_get_block_info(dev, selected);
2832                         dev->gc_pages_in_use =
2833                             bi->pages_in_use - bi->soft_del_pages;
2834                 } else {
2835                         dev->gc_not_done = 0;
2836                 }
2837         }
2838
2839         if (selected) {
2840                 yaffs_trace(YAFFS_TRACE_GC,
2841                         "GC Selected block %d with %d free, prioritised:%d",
2842                         selected,
2843                         dev->param.chunks_per_block - dev->gc_pages_in_use,
2844                         prioritised);
2845
2846                 dev->n_gc_blocks++;
2847                 if (background)
2848                         dev->bg_gcs++;
2849
2850                 dev->gc_dirtiest = 0;
2851                 dev->gc_pages_in_use = 0;
2852                 dev->gc_not_done = 0;
2853                 if (dev->refresh_skip > 0)
2854                         dev->refresh_skip--;
2855         } else {
2856                 dev->gc_not_done++;
2857                 yaffs_trace(YAFFS_TRACE_GC,
2858                         "GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s",
2859                         dev->gc_block_finder, dev->gc_not_done, threshold,
2860                         dev->gc_dirtiest, dev->gc_pages_in_use,
2861                         dev->oldest_dirty_block, background ? " bg" : "");
2862         }
2863
2864         return selected;
2865 }
2866
2867 /* New garbage collector
2868  * If we're very low on erased blocks then we do aggressive garbage collection
2869  * otherwise we do "leasurely" garbage collection.
2870  * Aggressive gc looks further (whole array) and will accept less dirty blocks.
2871  * Passive gc only inspects smaller areas and only accepts more dirty blocks.
2872  *
2873  * The idea is to help clear out space in a more spread-out manner.
2874  * Dunno if it really does anything useful.
2875  */
2876 static int yaffs_check_gc(struct yaffs_dev *dev, int background)
2877 {
2878         int aggressive = 0;
2879         int gc_ok = YAFFS_OK;
2880         int max_tries = 0;
2881         int min_erased;
2882         int erased_chunks;
2883         int checkpt_block_adjust;
2884
2885         if (dev->param.gc_control_fn &&
2886                 (dev->param.gc_control_fn(dev) & 1) == 0)
2887                 return YAFFS_OK;
2888
2889         if (dev->gc_disable)
2890                 /* Bail out so we don't get recursive gc */
2891                 return YAFFS_OK;
2892
2893         /* This loop should pass the first time.
2894          * Only loops here if the collection does not increase space.
2895          */
2896
2897         do {
2898                 max_tries++;
2899
2900                 checkpt_block_adjust = yaffs_calc_checkpt_blocks_required(dev);
2901
2902                 min_erased =
2903                     dev->param.n_reserved_blocks + checkpt_block_adjust + 1;
2904                 erased_chunks =
2905                     dev->n_erased_blocks * dev->param.chunks_per_block;
2906
2907                 /* If we need a block soon then do aggressive gc. */
2908                 if (dev->n_erased_blocks < min_erased)
2909                         aggressive = 1;
2910                 else {
2911                         if (!background
2912                             && erased_chunks > (dev->n_free_chunks / 4))
2913                                 break;
2914
2915                         if (dev->gc_skip > 20)
2916                                 dev->gc_skip = 20;
2917                         if (erased_chunks < dev->n_free_chunks / 2 ||
2918                             dev->gc_skip < 1 || background)
2919                                 aggressive = 0;
2920                         else {
2921                                 dev->gc_skip--;
2922                                 break;
2923                         }
2924                 }
2925
2926                 dev->gc_skip = 5;
2927
2928                 /* If we don't already have a block being gc'd then see if we
2929                  * should start another */
2930
2931                 if (dev->gc_block < 1 && !aggressive) {
2932                         dev->gc_block = yaffs2_find_refresh_block(dev);
2933                         dev->gc_chunk = 0;
2934                         dev->n_clean_ups = 0;
2935                 }
2936                 if (dev->gc_block < 1) {
2937                         dev->gc_block =
2938                             yaffs_find_gc_block(dev, aggressive, background);
2939                         dev->gc_chunk = 0;
2940                         dev->n_clean_ups = 0;
2941                 }
2942
2943                 if (dev->gc_block > 0) {
2944                         dev->all_gcs++;
2945                         if (!aggressive)
2946                                 dev->passive_gc_count++;
2947
2948                         yaffs_trace(YAFFS_TRACE_GC,
2949                                 "yaffs: GC n_erased_blocks %d aggressive %d",
2950                                 dev->n_erased_blocks, aggressive);
2951
2952                         gc_ok = yaffs_gc_block(dev, dev->gc_block, aggressive);
2953                 }
2954
2955                 if (dev->n_erased_blocks < (dev->param.n_reserved_blocks) &&
2956                     dev->gc_block > 0) {
2957                         yaffs_trace(YAFFS_TRACE_GC,
2958                                 "yaffs: GC !!!no reclaim!!! n_erased_blocks %d after try %d block %d",
2959                                 dev->n_erased_blocks, max_tries,
2960                                 dev->gc_block);
2961                 }
2962         } while ((dev->n_erased_blocks < dev->param.n_reserved_blocks) &&
2963                  (dev->gc_block > 0) && (max_tries < 2));
2964
2965         return aggressive ? gc_ok : YAFFS_OK;
2966 }
2967
2968 /*
2969  * yaffs_bg_gc()
2970  * Garbage collects. Intended to be called from a background thread.
2971  * Returns non-zero if at least half the free chunks are erased.
2972  */
2973 int yaffs_bg_gc(struct yaffs_dev *dev, unsigned urgency)
2974 {
2975         int erased_chunks = dev->n_erased_blocks * dev->param.chunks_per_block;
2976
2977         yaffs_trace(YAFFS_TRACE_BACKGROUND, "Background gc %u", urgency);
2978
2979         yaffs_check_gc(dev, 1);
2980         return erased_chunks > dev->n_free_chunks / 2;
2981 }
2982
2983 /*-------------------- Data file manipulation -----------------*/
2984
2985 static int yaffs_rd_data_obj(struct yaffs_obj *in, int inode_chunk, u8 * buffer)
2986 {
2987         int nand_chunk = yaffs_find_chunk_in_file(in, inode_chunk, NULL);
2988
2989         if (nand_chunk >= 0)
2990                 return yaffs_rd_chunk_tags_nand(in->my_dev, nand_chunk,
2991                                                 buffer, NULL);
2992         else {
2993                 yaffs_trace(YAFFS_TRACE_NANDACCESS,
2994                         "Chunk %d not found zero instead",
2995                         nand_chunk);
2996                 /* get sane (zero) data if you read a hole */
2997                 memset(buffer, 0, in->my_dev->data_bytes_per_chunk);
2998                 return 0;
2999         }
3000
3001 }
3002
3003 void yaffs_chunk_del(struct yaffs_dev *dev, int chunk_id, int mark_flash,
3004                      int lyn)
3005 {
3006         int block;
3007         int page;
3008         struct yaffs_ext_tags tags;
3009         struct yaffs_block_info *bi;
3010
3011         if (chunk_id <= 0)
3012                 return;
3013
3014         dev->n_deletions++;
3015         block = chunk_id / dev->param.chunks_per_block;
3016         page = chunk_id % dev->param.chunks_per_block;
3017
3018         if (!yaffs_check_chunk_bit(dev, block, page))
3019                 yaffs_trace(YAFFS_TRACE_VERIFY,
3020                         "Deleting invalid chunk %d", chunk_id);
3021
3022         bi = yaffs_get_block_info(dev, block);
3023
3024         yaffs2_update_oldest_dirty_seq(dev, block, bi);
3025
3026         yaffs_trace(YAFFS_TRACE_DELETION,
3027                 "line %d delete of chunk %d",
3028                 lyn, chunk_id);
3029
3030         if (!dev->param.is_yaffs2 && mark_flash &&
3031             bi->block_state != YAFFS_BLOCK_STATE_COLLECTING) {
3032
3033                 memset(&tags, 0, sizeof(tags));
3034                 tags.is_deleted = 1;
3035                 yaffs_wr_chunk_tags_nand(dev, chunk_id, NULL, &tags);
3036                 yaffs_handle_chunk_update(dev, chunk_id, &tags);
3037         } else {
3038                 dev->n_unmarked_deletions++;
3039         }
3040
3041         /* Pull out of the management area.
3042          * If the whole block became dirty, this will kick off an erasure.
3043          */
3044         if (bi->block_state == YAFFS_BLOCK_STATE_ALLOCATING ||
3045             bi->block_state == YAFFS_BLOCK_STATE_FULL ||
3046             bi->block_state == YAFFS_BLOCK_STATE_NEEDS_SCAN ||
3047             bi->block_state == YAFFS_BLOCK_STATE_COLLECTING) {
3048                 dev->n_free_chunks++;
3049                 yaffs_clear_chunk_bit(dev, block, page);
3050                 bi->pages_in_use--;
3051
3052                 if (bi->pages_in_use == 0 &&
3053                     !bi->has_shrink_hdr &&
3054                     bi->block_state != YAFFS_BLOCK_STATE_ALLOCATING &&
3055                     bi->block_state != YAFFS_BLOCK_STATE_NEEDS_SCAN) {
3056                         yaffs_block_became_dirty(dev, block);
3057                 }
3058         }
3059 }
3060
3061 static int yaffs_wr_data_obj(struct yaffs_obj *in, int inode_chunk,
3062                              const u8 *buffer, int n_bytes, int use_reserve)
3063 {
3064         /* Find old chunk Need to do this to get serial number
3065          * Write new one and patch into tree.
3066          * Invalidate old tags.
3067          */
3068
3069         int prev_chunk_id;
3070         struct yaffs_ext_tags prev_tags;
3071         int new_chunk_id;
3072         struct yaffs_ext_tags new_tags;
3073         struct yaffs_dev *dev = in->my_dev;
3074
3075         yaffs_check_gc(dev, 0);
3076
3077         /* Get the previous chunk at this location in the file if it exists.
3078          * If it does not exist then put a zero into the tree. This creates
3079          * the tnode now, rather than later when it is harder to clean up.
3080          */
3081         prev_chunk_id = yaffs_find_chunk_in_file(in, inode_chunk, &prev_tags);
3082         if (prev_chunk_id < 1 &&
3083             !yaffs_put_chunk_in_file(in, inode_chunk, 0, 0))
3084                 return 0;
3085
3086         /* Set up new tags */
3087         memset(&new_tags, 0, sizeof(new_tags));
3088
3089         new_tags.chunk_id = inode_chunk;
3090         new_tags.obj_id = in->obj_id;
3091         new_tags.serial_number =
3092             (prev_chunk_id > 0) ? prev_tags.serial_number + 1 : 1;
3093         new_tags.n_bytes = n_bytes;
3094
3095         if (n_bytes < 1 || (u32)n_bytes > dev->param.total_bytes_per_chunk) {
3096                 yaffs_trace(YAFFS_TRACE_ERROR,
3097                   "Writing %d bytes to chunk!!!!!!!!!",
3098                    n_bytes);
3099                 BUG();
3100         }
3101
3102         new_chunk_id =
3103             yaffs_write_new_chunk(dev, buffer, &new_tags, use_reserve);
3104
3105         if (new_chunk_id > 0) {
3106                 yaffs_put_chunk_in_file(in, inode_chunk, new_chunk_id, 0);
3107
3108                 if (prev_chunk_id > 0)
3109                         yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
3110
3111                 yaffs_verify_file_sane(in);
3112         }
3113         return new_chunk_id;
3114
3115 }
3116
3117
3118
3119 static int yaffs_do_xattrib_mod(struct yaffs_obj *obj, int set,
3120                                 const YCHAR *name, const void *value, int size,
3121                                 int flags)
3122 {
3123         struct yaffs_xattr_mod xmod;
3124         int result;
3125
3126         xmod.set = set;
3127         xmod.name = name;
3128         xmod.data = value;
3129         xmod.size = size;
3130         xmod.flags = flags;
3131         xmod.result = -ENOSPC;
3132
3133         result = yaffs_update_oh(obj, NULL, 0, 0, 0, &xmod);
3134
3135         if (result > 0)
3136                 return xmod.result;
3137         else
3138                 return -ENOSPC;
3139 }
3140
3141 static int yaffs_apply_xattrib_mod(struct yaffs_obj *obj, char *buffer,
3142                                    struct yaffs_xattr_mod *xmod)
3143 {
3144         int retval = 0;
3145         int x_offs = sizeof(struct yaffs_obj_hdr);
3146         struct yaffs_dev *dev = obj->my_dev;
3147         int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
3148         char *x_buffer = buffer + x_offs;
3149
3150         if (xmod->set)
3151                 retval =
3152                     nval_set(x_buffer, x_size, xmod->name, xmod->data,
3153                              xmod->size, xmod->flags);
3154         else
3155                 retval = nval_del(x_buffer, x_size, xmod->name);
3156
3157         obj->has_xattr = nval_hasvalues(x_buffer, x_size);
3158         obj->xattr_known = 1;
3159         xmod->result = retval;
3160
3161         return retval;
3162 }
3163
3164 static int yaffs_do_xattrib_fetch(struct yaffs_obj *obj, const YCHAR *name,
3165                                   void *value, int size)
3166 {
3167         char *buffer = NULL;
3168         int result;
3169         struct yaffs_ext_tags tags;
3170         struct yaffs_dev *dev = obj->my_dev;
3171         int x_offs = sizeof(struct yaffs_obj_hdr);
3172         int x_size = dev->data_bytes_per_chunk - sizeof(struct yaffs_obj_hdr);
3173         char *x_buffer;
3174         int retval = 0;
3175
3176         if (obj->hdr_chunk < 1)
3177                 return -ENODATA;
3178
3179         /* If we know that the object has no xattribs then don't do all the
3180          * reading and parsing.
3181          */
3182         if (obj->xattr_known && !obj->has_xattr) {
3183                 if (name)
3184                         return -ENODATA;
3185                 else
3186                         return 0;
3187         }
3188
3189         buffer = (char *)yaffs_get_temp_buffer(dev);
3190         if (!buffer)
3191                 return -ENOMEM;
3192
3193         result =
3194             yaffs_rd_chunk_tags_nand(dev, obj->hdr_chunk, (u8 *) buffer, &tags);
3195
3196         if (result != YAFFS_OK)
3197                 retval = -ENOENT;
3198         else {
3199                 x_buffer = buffer + x_offs;
3200
3201                 if (!obj->xattr_known) {
3202                         obj->has_xattr = nval_hasvalues(x_buffer, x_size);
3203                         obj->xattr_known = 1;
3204                 }
3205
3206                 if (name)
3207                         retval = nval_get(x_buffer, x_size, name, value, size);
3208                 else
3209                         retval = nval_list(x_buffer, x_size, value, size);
3210         }
3211         yaffs_release_temp_buffer(dev, (u8 *) buffer);
3212         return retval;
3213 }
3214
3215 int yaffs_set_xattrib(struct yaffs_obj *obj, const YCHAR * name,
3216                       const void *value, int size, int flags)
3217 {
3218         return yaffs_do_xattrib_mod(obj, 1, name, value, size, flags);
3219 }
3220
3221 int yaffs_remove_xattrib(struct yaffs_obj *obj, const YCHAR * name)
3222 {
3223         return yaffs_do_xattrib_mod(obj, 0, name, NULL, 0, 0);
3224 }
3225
3226 int yaffs_get_xattrib(struct yaffs_obj *obj, const YCHAR * name, void *value,
3227                       int size)
3228 {
3229         return yaffs_do_xattrib_fetch(obj, name, value, size);
3230 }
3231
3232 int yaffs_list_xattrib(struct yaffs_obj *obj, char *buffer, int size)
3233 {
3234         return yaffs_do_xattrib_fetch(obj, NULL, buffer, size);
3235 }
3236
3237 static void yaffs_check_obj_details_loaded(struct yaffs_obj *in)
3238 {
3239         u8 *buf;
3240         struct yaffs_obj_hdr *oh;
3241         struct yaffs_dev *dev;
3242         struct yaffs_ext_tags tags;
3243         //int result;
3244         //int alloc_failed = 0;
3245
3246         if (!in || !in->lazy_loaded || in->hdr_chunk < 1)
3247                 return;
3248
3249         dev = in->my_dev;
3250         in->lazy_loaded = 0;
3251         buf = yaffs_get_temp_buffer(dev);
3252
3253         if (!yaffs_rd_chunk_tags_nand(dev, in->hdr_chunk, buf, &tags))
3254         {
3255                 yaffs_trace(YAFFS_TRACE_ERROR, "yaffs_check_obj_details_loaded: unhandled error from rd_chunk_tags_nand");
3256         }
3257         oh = (struct yaffs_obj_hdr *)buf;
3258
3259         in->yst_mode = oh->yst_mode;
3260         yaffs_load_attribs(in, oh);
3261         yaffs_set_obj_name_from_oh(in, oh);
3262
3263         if (in->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
3264                 in->variant.symlink_variant.alias =
3265                     yaffs_clone_str(oh->alias);
3266                 if (!in->variant.symlink_variant.alias)
3267                 {
3268                 //      alloc_failed = 1;
3269                     yaffs_trace(YAFFS_TRACE_ERROR, "yaffs_check_obj_details_loaded: alloc_failed = 1??");
3270                 }
3271         }
3272         yaffs_release_temp_buffer(dev, buf);
3273 }
3274
3275 /* UpdateObjectHeader updates the header on NAND for an object.
3276  * If name is not NULL, then that new name is used.
3277  */
3278 int yaffs_update_oh(struct yaffs_obj *in, const YCHAR *name, int force,
3279                     int is_shrink, int shadows, struct yaffs_xattr_mod *xmod)
3280 {
3281
3282         struct yaffs_block_info *bi;
3283         struct yaffs_dev *dev = in->my_dev;
3284         int prev_chunk_id;
3285         int ret_val = 0;
3286         //int result = 0;
3287         int new_chunk_id;
3288         struct yaffs_ext_tags new_tags;
3289         struct yaffs_ext_tags old_tags;
3290         const YCHAR *alias = NULL;
3291         u8 *buffer = NULL;
3292         YCHAR old_name[YAFFS_MAX_NAME_LENGTH + 1];
3293         struct yaffs_obj_hdr *oh = NULL;
3294         Y_LOFF_T file_size = 0;
3295
3296         yaffs_strcpy(old_name, _Y("silly old name"));
3297
3298         if (in->fake && in != dev->root_dir && !force && !xmod)
3299                 return ret_val;
3300
3301         yaffs_check_gc(dev, 0);
3302         yaffs_check_obj_details_loaded(in);
3303
3304         buffer = yaffs_get_temp_buffer(in->my_dev);
3305         oh = (struct yaffs_obj_hdr *)buffer;
3306
3307         prev_chunk_id = in->hdr_chunk;
3308
3309         if (prev_chunk_id > 0) {
3310                 if (!yaffs_rd_chunk_tags_nand(dev, prev_chunk_id, buffer, &old_tags))
3311                 {
3312                     yaffs_trace(YAFFS_TRACE_ERROR, "yaffs_update_oh: unhandled error from rd_chunk_tags_nand");
3313                 }
3314
3315                 yaffs_verify_oh(in, oh, &old_tags, 0);
3316                 memcpy(old_name, oh->name, sizeof(oh->name));
3317                 memset(buffer, 0xff, sizeof(struct yaffs_obj_hdr));
3318         } else {
3319                 memset(buffer, 0xff, dev->data_bytes_per_chunk);
3320         }
3321
3322         oh->type = in->variant_type;
3323         oh->yst_mode = in->yst_mode;
3324         oh->shadows_obj = oh->inband_shadowed_obj_id = shadows;
3325
3326         yaffs_load_attribs_oh(oh, in);
3327
3328         if (in->parent)
3329                 oh->parent_obj_id = in->parent->obj_id;
3330         else
3331                 oh->parent_obj_id = 0;
3332
3333         if (name && *name) {
3334                 memset(oh->name, 0, sizeof(oh->name));
3335                 yaffs_load_oh_from_name(dev, oh->name, name);
3336         } else if (prev_chunk_id > 0) {
3337                 memcpy(oh->name, old_name, sizeof(oh->name));
3338         } else {
3339                 memset(oh->name, 0, sizeof(oh->name));
3340         }
3341
3342         oh->is_shrink = is_shrink;
3343
3344         switch (in->variant_type) {
3345         case YAFFS_OBJECT_TYPE_UNKNOWN:
3346                 /* Should not happen */
3347                 break;
3348         case YAFFS_OBJECT_TYPE_FILE:
3349                 if (oh->parent_obj_id != YAFFS_OBJECTID_DELETED &&
3350                     oh->parent_obj_id != YAFFS_OBJECTID_UNLINKED)
3351                         file_size = in->variant.file_variant.file_size;
3352                 yaffs_oh_size_load(oh, file_size);
3353                 break;
3354         case YAFFS_OBJECT_TYPE_HARDLINK:
3355                 oh->equiv_id = in->variant.hardlink_variant.equiv_id;
3356                 break;
3357         case YAFFS_OBJECT_TYPE_SPECIAL:
3358                 /* Do nothing */
3359                 break;
3360         case YAFFS_OBJECT_TYPE_DIRECTORY:
3361                 /* Do nothing */
3362                 break;
3363         case YAFFS_OBJECT_TYPE_SYMLINK:
3364                 alias = in->variant.symlink_variant.alias;
3365                 if (!alias)
3366                         alias = _Y("no alias");
3367                 yaffs_strncpy(oh->alias, alias, YAFFS_MAX_ALIAS_LENGTH);
3368                 oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
3369                 break;
3370         }
3371
3372         /* process any xattrib modifications */
3373         if (xmod)
3374                 yaffs_apply_xattrib_mod(in, (char *)buffer, xmod);
3375
3376         /* Tags */
3377         memset(&new_tags, 0, sizeof(new_tags));
3378         in->serial++;
3379         new_tags.chunk_id = 0;
3380         new_tags.obj_id = in->obj_id;
3381         new_tags.serial_number = in->serial;
3382
3383         /* Add extra info for file header */
3384         new_tags.extra_available = 1;
3385         new_tags.extra_parent_id = oh->parent_obj_id;
3386         new_tags.extra_file_size = file_size;
3387         new_tags.extra_is_shrink = oh->is_shrink;
3388         new_tags.extra_equiv_id = oh->equiv_id;
3389         new_tags.extra_shadows = (oh->shadows_obj > 0) ? 1 : 0;
3390         new_tags.extra_obj_type = in->variant_type;
3391         yaffs_verify_oh(in, oh, &new_tags, 1);
3392
3393         /* Create new chunk in NAND */
3394         new_chunk_id =
3395             yaffs_write_new_chunk(dev, buffer, &new_tags,
3396                                   (prev_chunk_id > 0) ? 1 : 0);
3397
3398         if (buffer)
3399                 yaffs_release_temp_buffer(dev, buffer);
3400
3401         if (new_chunk_id < 0)
3402                 return new_chunk_id;
3403
3404         in->hdr_chunk = new_chunk_id;
3405
3406         if (prev_chunk_id > 0)
3407                 yaffs_chunk_del(dev, prev_chunk_id, 1, __LINE__);
3408
3409         if (!yaffs_obj_cache_dirty(in))
3410                 in->dirty = 0;
3411
3412         /* If this was a shrink, then mark the block
3413          * that the chunk lives on */
3414         if (is_shrink) {
3415                 bi = yaffs_get_block_info(in->my_dev,
3416                                           new_chunk_id /
3417                                           in->my_dev->param.chunks_per_block);
3418                 bi->has_shrink_hdr = 1;
3419         }
3420
3421
3422         return new_chunk_id;
3423 }
3424
3425 /*--------------------- File read/write ------------------------
3426  * Read and write have very similar structures.
3427  * In general the read/write has three parts to it
3428  * An incomplete chunk to start with (if the read/write is not chunk-aligned)
3429  * Some complete chunks
3430  * An incomplete chunk to end off with
3431  *
3432  * Curve-balls: the first chunk might also be the last chunk.
3433  */
3434
3435 int yaffs_file_rd(struct yaffs_obj *in, u8 * buffer, Y_LOFF_T offset, int n_bytes)
3436 {
3437         int chunk;
3438         u32 start;
3439         int n_copy;
3440         int n = n_bytes;
3441         int n_done = 0;
3442         struct yaffs_cache *cache;
3443         struct yaffs_dev *dev;
3444
3445         dev = in->my_dev;
3446
3447         while (n > 0) {
3448                 yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3449                 chunk++;
3450
3451                 /* OK now check for the curveball where the start and end are in
3452                  * the same chunk.
3453                  */
3454                 if ((start + n) < (u32)dev->data_bytes_per_chunk)
3455                         n_copy = n;
3456                 else
3457                         n_copy = dev->data_bytes_per_chunk - start;
3458
3459                 cache = yaffs_find_chunk_cache(in, chunk);
3460
3461                 /* If the chunk is already in the cache or it is less than
3462                  * a whole chunk or we're using inband tags then use the cache
3463                  * (if there is caching) else bypass the cache.
3464                  */
3465                 if (cache || n_copy != dev->data_bytes_per_chunk ||
3466                     dev->param.inband_tags) {
3467                         if (dev->param.n_caches > 0) {
3468
3469                                 /* If we can't find the data in the cache,
3470                                  * then load it up. */
3471
3472                                 if (!cache) {
3473                                         cache =
3474                                             yaffs_grab_chunk_cache(in->my_dev);
3475                                         cache->object = in;
3476                                         cache->chunk_id = chunk;
3477                                         cache->dirty = 0;
3478                                         cache->locked = 0;
3479                                         yaffs_rd_data_obj(in, chunk,
3480                                                           cache->data);
3481                                         cache->n_bytes = 0;
3482                                 }
3483
3484                                 yaffs_use_cache(dev, cache, 0);
3485
3486                                 cache->locked = 1;
3487
3488                                 memcpy(buffer, &cache->data[start], n_copy);
3489
3490                                 cache->locked = 0;
3491                         } else {
3492                                 /* Read into the local buffer then copy.. */
3493
3494                                 u8 *local_buffer =
3495                                     yaffs_get_temp_buffer(dev);
3496                                 yaffs_rd_data_obj(in, chunk, local_buffer);
3497
3498                                 memcpy(buffer, &local_buffer[start], n_copy);
3499
3500                                 yaffs_release_temp_buffer(dev, local_buffer);
3501                         }
3502                 } else {
3503                         /* A full chunk. Read directly into the buffer. */
3504                         yaffs_rd_data_obj(in, chunk, buffer);
3505                 }
3506                 n -= n_copy;
3507                 offset += n_copy;
3508                 buffer += n_copy;
3509                 n_done += n_copy;
3510         }
3511         return n_done;
3512 }
3513
3514 int yaffs_do_file_wr(struct yaffs_obj *in, const u8 *buffer, Y_LOFF_T offset,
3515                      int n_bytes, int write_through)
3516 {
3517
3518         int chunk;
3519         u32 start;
3520         int n_copy;
3521         int n = n_bytes;
3522         int n_done = 0;
3523         int n_writeback;
3524         Y_LOFF_T start_write = offset;
3525         int chunk_written = 0;
3526         u32 n_bytes_read;
3527         Y_LOFF_T chunk_start;
3528         struct yaffs_dev *dev;
3529
3530         dev = in->my_dev;
3531
3532         while (n > 0 && chunk_written >= 0) {
3533                 yaffs_addr_to_chunk(dev, offset, &chunk, &start);
3534
3535                 if (((Y_LOFF_T)chunk) *
3536                     (s32)(dev->data_bytes_per_chunk + start) != offset ||
3537                     (s32)start >= dev->data_bytes_per_chunk) {
3538                         yaffs_trace(YAFFS_TRACE_ERROR,
3539                                 "AddrToChunk of offset %ud gives chunk %d start %d",
3540                                 (unsigned int)offset, chunk, start);
3541                 }
3542                 chunk++;        /* File pos to chunk in file offset */
3543
3544                 /* OK now check for the curveball where the start and end are in
3545                  * the same chunk.
3546                  */
3547
3548                 if ((start + n) < (u32)dev->data_bytes_per_chunk) {
3549                         n_copy = n;
3550
3551                         /* Now calculate how many bytes to write back....
3552                          * If we're overwriting and not writing to then end of
3553                          * file then we need to write back as much as was there
3554                          * before.
3555                          */
3556
3557                         chunk_start = (((Y_LOFF_T)(chunk - 1)) *
3558                                         dev->data_bytes_per_chunk);
3559
3560                         if (chunk_start > in->variant.file_variant.file_size)
3561                                 n_bytes_read = 0;       /* Past end of file */
3562                         else
3563                                 n_bytes_read =
3564                                     in->variant.file_variant.file_size -
3565                                     chunk_start;
3566
3567                         if ((int)n_bytes_read > dev->data_bytes_per_chunk)
3568                                 n_bytes_read = dev->data_bytes_per_chunk;
3569
3570                         n_writeback =
3571                             (n_bytes_read >
3572                              (start + n)) ? n_bytes_read : (start + n);
3573
3574                         if (n_writeback < 0 ||
3575                             n_writeback > dev->data_bytes_per_chunk)
3576                                 BUG();
3577
3578                 } else {
3579                         n_copy = dev->data_bytes_per_chunk - start;
3580                         n_writeback = dev->data_bytes_per_chunk;
3581                 }
3582
3583                 if (n_copy != dev->data_bytes_per_chunk ||
3584                     !dev->param.cache_bypass_aligned ||
3585                     dev->param.inband_tags) {
3586                         /* An incomplete start or end chunk (or maybe both
3587                          * start and end chunk), or we're using inband tags,
3588                          * or we're forcing writes through the cache,
3589                          * so we want to use the cache buffers.
3590                          */
3591                         if (dev->param.n_caches > 0) {
3592                                 struct yaffs_cache *cache;
3593
3594                                 /* If we can't find the data in the cache, then
3595                                  * load the cache */
3596                                 cache = yaffs_find_chunk_cache(in, chunk);
3597
3598                                 if (!cache &&
3599                                     yaffs_check_alloc_available(dev, 1)) {
3600                                         cache = yaffs_grab_chunk_cache(dev);
3601                                         cache->object = in;
3602                                         cache->chunk_id = chunk;
3603                                         cache->dirty = 0;
3604                                         cache->locked = 0;
3605                                         yaffs_rd_data_obj(in, chunk,
3606                                                           cache->data);
3607                                 } else if (cache &&
3608                                            !cache->dirty &&
3609                                            !yaffs_check_alloc_available(dev,
3610                                                                         1)) {
3611                                         /* Drop the cache if it was a read cache
3612                                          * item and no space check has been made
3613                                          * for it.
3614                                          */
3615                                         cache = NULL;
3616                                 }
3617
3618                                 if (cache) {
3619                                         yaffs_use_cache(dev, cache, 1);
3620                                         cache->locked = 1;
3621
3622                                         memcpy(&cache->data[start], buffer,
3623                                                n_copy);
3624
3625                                         cache->locked = 0;
3626                                         cache->n_bytes = n_writeback;
3627
3628                                         if (write_through) {
3629                                                 chunk_written =
3630                                                     yaffs_wr_data_obj
3631                                                     (cache->object,
3632                                                      cache->chunk_id,
3633                                                      cache->data,
3634                                                      cache->n_bytes, 1);
3635                                                 cache->dirty = 0;
3636                                         }
3637                                 } else {
3638                                         chunk_written = -1;     /* fail write */
3639                                 }
3640                         } else {
3641                                 /* An incomplete start or end chunk (or maybe
3642                                  * both start and end chunk). Read into the
3643                                  * local buffer then copy over and write back.
3644                                  */
3645
3646                                 u8 *local_buffer = yaffs_get_temp_buffer(dev);
3647
3648                                 yaffs_rd_data_obj(in, chunk, local_buffer);
3649                                 memcpy(&local_buffer[start], buffer, n_copy);
3650
3651                                 chunk_written =
3652                                     yaffs_wr_data_obj(in, chunk,
3653                                                       local_buffer,
3654                                                       n_writeback, 0);
3655
3656                                 yaffs_release_temp_buffer(dev, local_buffer);
3657                         }
3658                 } else {
3659                         /* A full chunk. Write directly from the buffer. */
3660
3661                         chunk_written =
3662                             yaffs_wr_data_obj(in, chunk, buffer,
3663                                               dev->data_bytes_per_chunk, 0);
3664
3665                         /* Since we've overwritten the cached data,
3666                          * we better invalidate it. */
3667                         yaffs_invalidate_chunk_cache(in, chunk);
3668                 }
3669
3670                 if (chunk_written >= 0) {
3671                         n -= n_copy;
3672                         offset += n_copy;
3673                         buffer += n_copy;
3674                         n_done += n_copy;
3675                 }
3676         }
3677
3678         /* Update file object */
3679
3680         if ((start_write + n_done) > in->variant.file_variant.file_size)
3681                 in->variant.file_variant.file_size = (start_write + n_done);
3682
3683         in->dirty = 1;
3684         return n_done;
3685 }
3686
3687 int yaffs_wr_file(struct yaffs_obj *in, const u8 *buffer, Y_LOFF_T offset,
3688                   int n_bytes, int write_through)
3689 {
3690         yaffs2_handle_hole(in, offset);
3691         return yaffs_do_file_wr(in, buffer, offset, n_bytes, write_through);
3692 }
3693
3694 /* ---------------------- File resizing stuff ------------------ */
3695
3696 static void yaffs_prune_chunks(struct yaffs_obj *in, Y_LOFF_T new_size)
3697 {
3698
3699         struct yaffs_dev *dev = in->my_dev;
3700         Y_LOFF_T old_size = in->variant.file_variant.file_size;
3701         int i;
3702         int chunk_id;
3703         u32 dummy;
3704         int last_del;
3705         int start_del;
3706
3707         if (old_size > 0)
3708                 yaffs_addr_to_chunk(dev, old_size - 1, &last_del, &dummy);
3709         else
3710                 last_del = 0;
3711
3712         yaffs_addr_to_chunk(dev, new_size + dev->data_bytes_per_chunk - 1,
3713                                 &start_del, &dummy);
3714         last_del++;
3715         start_del++;
3716
3717         /* Delete backwards so that we don't end up with holes if
3718          * power is lost part-way through the operation.
3719          */
3720         for (i = last_del; i >= start_del; i--) {
3721                 /* NB this could be optimised somewhat,
3722                  * eg. could retrieve the tags and write them without
3723                  * using yaffs_chunk_del
3724                  */
3725
3726                 chunk_id = yaffs_find_del_file_chunk(in, i, NULL);
3727
3728                 if (chunk_id < 1)
3729                         continue;
3730
3731                 if (chunk_id <
3732                     (dev->internal_start_block * dev->param.chunks_per_block) ||
3733                     chunk_id >=
3734                     ((dev->internal_end_block + 1) *
3735                       dev->param.chunks_per_block)) {
3736                         yaffs_trace(YAFFS_TRACE_ALWAYS,
3737                                 "Found daft chunk_id %d for %d",
3738                                 chunk_id, i);
3739                 } else {
3740                         in->n_data_chunks--;
3741                         yaffs_chunk_del(dev, chunk_id, 1, __LINE__);
3742                 }
3743         }
3744 }
3745
3746 void yaffs_resize_file_down(struct yaffs_obj *obj, Y_LOFF_T new_size)
3747 {
3748         int new_full;
3749         u32 new_partial;
3750         struct yaffs_dev *dev = obj->my_dev;
3751
3752         yaffs_addr_to_chunk(dev, new_size, &new_full, &new_partial);
3753
3754         yaffs_prune_chunks(obj, new_size);
3755
3756         if (new_partial != 0) {
3757                 int last_chunk = 1 + new_full;
3758                 u8 *local_buffer = yaffs_get_temp_buffer(dev);
3759
3760                 /* Rewrite the last chunk with its new size and zero pad */
3761                 yaffs_rd_data_obj(obj, last_chunk, local_buffer);
3762                 memset(local_buffer + new_partial, 0,
3763                        dev->data_bytes_per_chunk - new_partial);
3764
3765                 yaffs_wr_data_obj(obj, last_chunk, local_buffer,
3766                                   new_partial, 1);
3767
3768                 yaffs_release_temp_buffer(dev, local_buffer);
3769         }
3770
3771         obj->variant.file_variant.file_size = new_size;
3772
3773         yaffs_prune_tree(dev, &obj->variant.file_variant);
3774 }
3775
3776 int yaffs_resize_file(struct yaffs_obj *in, Y_LOFF_T new_size)
3777 {
3778         struct yaffs_dev *dev = in->my_dev;
3779         Y_LOFF_T old_size = in->variant.file_variant.file_size;
3780
3781         yaffs_flush_file_cache(in, 1);
3782         yaffs_invalidate_whole_cache(in);
3783
3784         yaffs_check_gc(dev, 0);
3785
3786         if (in->variant_type != YAFFS_OBJECT_TYPE_FILE)
3787                 return YAFFS_FAIL;
3788
3789         if (new_size == old_size)
3790                 return YAFFS_OK;
3791
3792         if (new_size > old_size) {
3793                 yaffs2_handle_hole(in, new_size);
3794                 in->variant.file_variant.file_size = new_size;
3795         } else {
3796                 /* new_size < old_size */
3797                 yaffs_resize_file_down(in, new_size);
3798         }
3799
3800         /* Write a new object header to reflect the resize.
3801          * show we've shrunk the file, if need be
3802          * Do this only if the file is not in the deleted directories
3803          * and is not shadowed.
3804          */
3805         if (in->parent &&
3806             !in->is_shadowed &&
3807             in->parent->obj_id != YAFFS_OBJECTID_UNLINKED &&
3808             in->parent->obj_id != YAFFS_OBJECTID_DELETED)
3809                 yaffs_update_oh(in, NULL, 0, 0, 0, NULL);
3810
3811         return YAFFS_OK;
3812 }
3813
3814 int yaffs_flush_file(struct yaffs_obj *in,
3815                      int update_time,
3816                      int data_sync,
3817                      int discard_cache)
3818 {
3819         if (!in->dirty)
3820                 return YAFFS_OK;
3821
3822         yaffs_flush_file_cache(in, discard_cache);
3823
3824         if (data_sync)
3825                 return YAFFS_OK;
3826
3827         if (update_time)
3828                 yaffs_load_current_time(in, 0, 0);
3829
3830         return (yaffs_update_oh(in, NULL, 0, 0, 0, NULL) >= 0) ?
3831                                 YAFFS_OK : YAFFS_FAIL;
3832 }
3833
3834
3835 /* yaffs_del_file deletes the whole file data
3836  * and the inode associated with the file.
3837  * It does not delete the links associated with the file.
3838  */
3839 static int yaffs_unlink_file_if_needed(struct yaffs_obj *in)
3840 {
3841         int ret_val;
3842         int del_now = 0;
3843         struct yaffs_dev *dev = in->my_dev;
3844
3845         if (!in->my_inode)
3846                 del_now = 1;
3847
3848         if (del_now) {
3849                 ret_val =
3850                     yaffs_change_obj_name(in, in->my_dev->del_dir,
3851                                           _Y("deleted"), 0, 0);
3852                 yaffs_trace(YAFFS_TRACE_TRACING,
3853                         "yaffs: immediate deletion of file %d",
3854                         in->obj_id);
3855                 in->deleted = 1;
3856                 in->my_dev->n_deleted_files++;
3857                 if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3858                         yaffs_resize_file(in, 0);
3859                 yaffs_soft_del_file(in);
3860         } else {
3861                 ret_val =
3862                     yaffs_change_obj_name(in, in->my_dev->unlinked_dir,
3863                                           _Y("unlinked"), 0, 0);
3864         }
3865         return ret_val;
3866 }
3867
3868 static int yaffs_del_file(struct yaffs_obj *in)
3869 {
3870         int ret_val = YAFFS_OK;
3871         int deleted;    /* Need to cache value on stack if in is freed */
3872         struct yaffs_dev *dev = in->my_dev;
3873
3874         if (dev->param.disable_soft_del || dev->param.is_yaffs2)
3875                 yaffs_resize_file(in, 0);
3876
3877         if (in->n_data_chunks > 0) {
3878                 /* Use soft deletion if there is data in the file.
3879                  * That won't be the case if it has been resized to zero.
3880                  */
3881                 if (!in->unlinked)
3882                         ret_val = yaffs_unlink_file_if_needed(in);
3883
3884                 deleted = in->deleted;
3885
3886                 if (ret_val == YAFFS_OK && in->unlinked && !in->deleted) {
3887                         in->deleted = 1;
3888                         deleted = 1;
3889                         in->my_dev->n_deleted_files++;
3890                         yaffs_soft_del_file(in);
3891                 }
3892                 return deleted ? YAFFS_OK : YAFFS_FAIL;
3893         } else {
3894                 /* The file has no data chunks so we toss it immediately */
3895                 yaffs_free_tnode(in->my_dev, in->variant.file_variant.top);
3896                 in->variant.file_variant.top = NULL;
3897                 yaffs_generic_obj_del(in);
3898
3899                 return YAFFS_OK;
3900         }
3901 }
3902
3903 int yaffs_is_non_empty_dir(struct yaffs_obj *obj)
3904 {
3905         return (obj &&
3906                 obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY) &&
3907                 !(list_empty(&obj->variant.dir_variant.children));
3908 }
3909
3910 static int yaffs_del_dir(struct yaffs_obj *obj)
3911 {
3912         /* First check that the directory is empty. */
3913         if (yaffs_is_non_empty_dir(obj))
3914                 return YAFFS_FAIL;
3915
3916         return yaffs_generic_obj_del(obj);
3917 }
3918
3919 static int yaffs_del_symlink(struct yaffs_obj *in)
3920 {
3921         kfree(in->variant.symlink_variant.alias);
3922         in->variant.symlink_variant.alias = NULL;
3923
3924         return yaffs_generic_obj_del(in);
3925 }
3926
3927 static int yaffs_del_link(struct yaffs_obj *in)
3928 {
3929         /* remove this hardlink from the list associated with the equivalent
3930          * object
3931          */
3932         list_del_init(&in->hard_links);
3933         return yaffs_generic_obj_del(in);
3934 }
3935
3936 int yaffs_del_obj(struct yaffs_obj *obj)
3937 {
3938         int ret_val = -1;
3939
3940         switch (obj->variant_type) {
3941         case YAFFS_OBJECT_TYPE_FILE:
3942                 ret_val = yaffs_del_file(obj);
3943                 break;
3944         case YAFFS_OBJECT_TYPE_DIRECTORY:
3945                 if (!list_empty(&obj->variant.dir_variant.dirty)) {
3946                         yaffs_trace(YAFFS_TRACE_BACKGROUND,
3947                                 "Remove object %d from dirty directories",
3948                                 obj->obj_id);
3949                         list_del_init(&obj->variant.dir_variant.dirty);
3950                 }
3951                 return yaffs_del_dir(obj);
3952                 break;
3953         case YAFFS_OBJECT_TYPE_SYMLINK:
3954                 ret_val = yaffs_del_symlink(obj);
3955                 break;
3956         case YAFFS_OBJECT_TYPE_HARDLINK:
3957                 ret_val = yaffs_del_link(obj);
3958                 break;
3959         case YAFFS_OBJECT_TYPE_SPECIAL:
3960                 ret_val = yaffs_generic_obj_del(obj);
3961                 break;
3962         case YAFFS_OBJECT_TYPE_UNKNOWN:
3963                 ret_val = 0;
3964                 break;          /* should not happen. */
3965         }
3966         return ret_val;
3967 }
3968
3969
3970 static void yaffs_empty_dir_to_dir(struct yaffs_obj *from_dir,
3971                                    struct yaffs_obj *to_dir)
3972 {
3973         struct yaffs_obj *obj;
3974         struct list_head *lh;
3975         struct list_head *n;
3976
3977         list_for_each_safe(lh, n, &from_dir->variant.dir_variant.children) {
3978                 obj = list_entry(lh, struct yaffs_obj, siblings);
3979                 yaffs_add_obj_to_dir(to_dir, obj);
3980         }
3981 }
3982
3983 struct yaffs_obj *yaffs_retype_obj(struct yaffs_obj *obj,
3984                                    enum yaffs_obj_type type)
3985 {
3986         /* Tear down the old variant */
3987         switch (obj->variant_type) {
3988         case YAFFS_OBJECT_TYPE_FILE:
3989                 /* Nuke file data */
3990                 yaffs_resize_file(obj, 0);
3991                 yaffs_free_tnode(obj->my_dev, obj->variant.file_variant.top);
3992                 obj->variant.file_variant.top = NULL;
3993                 break;
3994         case YAFFS_OBJECT_TYPE_DIRECTORY:
3995                 /* Put the children in lost and found. */
3996                 yaffs_empty_dir_to_dir(obj, obj->my_dev->lost_n_found);
3997                 if (!list_empty(&obj->variant.dir_variant.dirty))
3998                         list_del_init(&obj->variant.dir_variant.dirty);
3999                 break;
4000         case YAFFS_OBJECT_TYPE_SYMLINK:
4001                 /* Nuke symplink data */
4002                 kfree(obj->variant.symlink_variant.alias);
4003                 obj->variant.symlink_variant.alias = NULL;
4004                 break;
4005         case YAFFS_OBJECT_TYPE_HARDLINK:
4006                 list_del_init(&obj->hard_links);
4007                 break;
4008         default:
4009                 break;
4010         }
4011
4012         memset(&obj->variant, 0, sizeof(obj->variant));
4013
4014         /*Set up new variant if the memset is not enough. */
4015         switch (type) {
4016         case YAFFS_OBJECT_TYPE_DIRECTORY:
4017                 INIT_LIST_HEAD(&obj->variant.dir_variant.children);
4018                 INIT_LIST_HEAD(&obj->variant.dir_variant.dirty);
4019                 break;
4020         case YAFFS_OBJECT_TYPE_FILE:
4021         case YAFFS_OBJECT_TYPE_SYMLINK:
4022         case YAFFS_OBJECT_TYPE_HARDLINK:
4023         default:
4024                 break;
4025         }
4026
4027         obj->variant_type = type;
4028
4029         return obj;
4030
4031 }
4032
4033 static int yaffs_unlink_worker(struct yaffs_obj *obj)
4034 {
4035         int del_now = 0;
4036
4037         if (!obj)
4038                 return YAFFS_FAIL;
4039
4040         if (!obj->my_inode)
4041                 del_now = 1;
4042
4043         yaffs_update_parent(obj->parent);
4044
4045         if (obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
4046                 return yaffs_del_link(obj);
4047         } else if (!list_empty(&obj->hard_links)) {
4048                 /* Curve ball: We're unlinking an object that has a hardlink.
4049                  *
4050                  * This problem arises because we are not strictly following
4051                  * The Linux link/inode model.
4052                  *
4053                  * We can't really delete the object.
4054                  * Instead, we do the following:
4055                  * - Select a hardlink.
4056                  * - Unhook it from the hard links
4057                  * - Move it from its parent directory so that the rename works.
4058                  * - Rename the object to the hardlink's name.
4059                  * - Delete the hardlink
4060                  */
4061
4062                 struct yaffs_obj *hl;
4063                 struct yaffs_obj *parent;
4064                 int ret_val;
4065                 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
4066
4067                 hl = list_entry(obj->hard_links.next, struct yaffs_obj,
4068                                 hard_links);
4069
4070                 yaffs_get_obj_name(hl, name, YAFFS_MAX_NAME_LENGTH + 1);
4071                 parent = hl->parent;
4072
4073                 list_del_init(&hl->hard_links);
4074
4075                 yaffs_add_obj_to_dir(obj->my_dev->unlinked_dir, hl);
4076
4077                 ret_val = yaffs_change_obj_name(obj, parent, name, 0, 0);
4078
4079                 if (ret_val == YAFFS_OK)
4080                         ret_val = yaffs_generic_obj_del(hl);
4081
4082                 return ret_val;
4083
4084         } else if (del_now) {
4085                 switch (obj->variant_type) {
4086                 case YAFFS_OBJECT_TYPE_FILE:
4087                         return yaffs_del_file(obj);
4088                         break;
4089                 case YAFFS_OBJECT_TYPE_DIRECTORY:
4090                         list_del_init(&obj->variant.dir_variant.dirty);
4091                         return yaffs_del_dir(obj);
4092                         break;
4093                 case YAFFS_OBJECT_TYPE_SYMLINK:
4094                         return yaffs_del_symlink(obj);
4095                         break;
4096                 case YAFFS_OBJECT_TYPE_SPECIAL:
4097                         return yaffs_generic_obj_del(obj);
4098                         break;
4099                 case YAFFS_OBJECT_TYPE_HARDLINK:
4100                 case YAFFS_OBJECT_TYPE_UNKNOWN:
4101                 default:
4102                         return YAFFS_FAIL;
4103                 }
4104         } else if (yaffs_is_non_empty_dir(obj)) {
4105                 return YAFFS_FAIL;
4106         } else {
4107                 return yaffs_change_obj_name(obj, obj->my_dev->unlinked_dir,
4108                                                 _Y("unlinked"), 0, 0);
4109         }
4110 }
4111
4112 static int yaffs_unlink_obj(struct yaffs_obj *obj)
4113 {
4114         if (obj && obj->unlink_allowed)
4115                 return yaffs_unlink_worker(obj);
4116
4117         return YAFFS_FAIL;
4118 }
4119
4120 int yaffs_unlinker(struct yaffs_obj *dir, const YCHAR *name)
4121 {
4122         struct yaffs_obj *obj;
4123
4124         obj = yaffs_find_by_name(dir, name);
4125         return yaffs_unlink_obj(obj);
4126 }
4127
4128 /* Note:
4129  * If old_name is NULL then we take old_dir as the object to be renamed.
4130  */
4131 int yaffs_rename_obj(struct yaffs_obj *old_dir, const YCHAR *old_name,
4132                      struct yaffs_obj *new_dir, const YCHAR *new_name)
4133 {
4134         struct yaffs_obj *obj = NULL;
4135         struct yaffs_obj *existing_target = NULL;
4136         int force = 0;
4137         int result;
4138         struct yaffs_dev *dev;
4139
4140         if (!old_dir || old_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4141                 BUG();
4142                 return YAFFS_FAIL;
4143         }
4144         if (!new_dir || new_dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4145                 BUG();
4146                 return YAFFS_FAIL;
4147         }
4148
4149         dev = old_dir->my_dev;
4150
4151 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
4152         /* Special case for case insemsitive systems.
4153          * While look-up is case insensitive, the name isn't.
4154          * Therefore we might want to change x.txt to X.txt
4155          */
4156         if (old_dir == new_dir &&
4157                 old_name && new_name &&
4158                 yaffs_strcmp(old_name, new_name) == 0)
4159                 force = 1;
4160 #endif
4161
4162         if (yaffs_strnlen(new_name, YAFFS_MAX_NAME_LENGTH + 1) >
4163             YAFFS_MAX_NAME_LENGTH)
4164                 /* ENAMETOOLONG */
4165                 return YAFFS_FAIL;
4166
4167         if (old_name)
4168                 obj = yaffs_find_by_name(old_dir, old_name);
4169         else{
4170                 obj = old_dir;
4171                 old_dir = obj->parent;
4172         }
4173
4174         if (obj && obj->rename_allowed) {
4175                 /* Now handle an existing target, if there is one */
4176                 existing_target = yaffs_find_by_name(new_dir, new_name);
4177                 if (yaffs_is_non_empty_dir(existing_target)) {
4178                         return YAFFS_FAIL;      /* ENOTEMPTY */
4179                 } else if (existing_target && existing_target != obj) {
4180                         /* Nuke the target first, using shadowing,
4181                          * but only if it isn't the same object.
4182                          *
4183                          * Note we must disable gc here otherwise it can mess
4184                          * up the shadowing.
4185                          *
4186                          */
4187                         dev->gc_disable = 1;
4188                         yaffs_change_obj_name(obj, new_dir, new_name, force,
4189                                               existing_target->obj_id);
4190                         existing_target->is_shadowed = 1;
4191                         yaffs_unlink_obj(existing_target);
4192                         dev->gc_disable = 0;
4193                 }
4194
4195                 result = yaffs_change_obj_name(obj, new_dir, new_name, 1, 0);
4196
4197                 yaffs_update_parent(old_dir);
4198                 if (new_dir != old_dir)
4199                         yaffs_update_parent(new_dir);
4200
4201                 return result;
4202         }
4203         return YAFFS_FAIL;
4204 }
4205
4206 /*----------------------- Initialisation Scanning ---------------------- */
4207
4208 void yaffs_handle_shadowed_obj(struct yaffs_dev *dev, int obj_id,
4209                                int backward_scanning)
4210 {
4211         struct yaffs_obj *obj;
4212
4213         if (backward_scanning) {
4214                 /* Handle YAFFS2 case (backward scanning)
4215                  * If the shadowed object exists then ignore.
4216                  */
4217                 obj = yaffs_find_by_number(dev, obj_id);
4218                 if (obj)
4219                         return;
4220         }
4221
4222         /* Let's create it (if it does not exist) assuming it is a file so that
4223          * it can do shrinking etc.
4224          * We put it in unlinked dir to be cleaned up after the scanning
4225          */
4226         obj =
4227             yaffs_find_or_create_by_number(dev, obj_id, YAFFS_OBJECT_TYPE_FILE);
4228         if (!obj)
4229                 return;
4230         obj->is_shadowed = 1;
4231         yaffs_add_obj_to_dir(dev->unlinked_dir, obj);
4232         obj->variant.file_variant.shrink_size = 0;
4233         obj->valid = 1;         /* So that we don't read any other info. */
4234 }
4235
4236 void yaffs_link_fixup(struct yaffs_dev *dev, struct list_head *hard_list)
4237 {
4238         struct list_head *lh;
4239         struct list_head *save;
4240         struct yaffs_obj *hl;
4241         struct yaffs_obj *in;
4242
4243         list_for_each_safe(lh, save, hard_list) {
4244                 hl = list_entry(lh, struct yaffs_obj, hard_links);
4245                 in = yaffs_find_by_number(dev,
4246                                         hl->variant.hardlink_variant.equiv_id);
4247
4248                 if (in) {
4249                         /* Add the hardlink pointers */
4250                         hl->variant.hardlink_variant.equiv_obj = in;
4251                         list_add(&hl->hard_links, &in->hard_links);
4252                 } else {
4253                         /* Todo Need to report/handle this better.
4254                          * Got a problem... hardlink to a non-existant object
4255                          */
4256                         hl->variant.hardlink_variant.equiv_obj = NULL;
4257                         INIT_LIST_HEAD(&hl->hard_links);
4258                 }
4259         }
4260 }
4261
4262 static void yaffs_strip_deleted_objs(struct yaffs_dev *dev)
4263 {
4264         /*
4265          *  Sort out state of unlinked and deleted objects after scanning.
4266          */
4267         struct list_head *i;
4268         struct list_head *n;
4269         struct yaffs_obj *l;
4270
4271         if (dev->read_only)
4272                 return;
4273
4274         /* Soft delete all the unlinked files */
4275         list_for_each_safe(i, n,
4276                            &dev->unlinked_dir->variant.dir_variant.children) {
4277                 l = list_entry(i, struct yaffs_obj, siblings);
4278                 yaffs_del_obj(l);
4279         }
4280
4281         list_for_each_safe(i, n, &dev->del_dir->variant.dir_variant.children) {
4282                 l = list_entry(i, struct yaffs_obj, siblings);
4283                 yaffs_del_obj(l);
4284         }
4285 }
4286
4287 /*
4288  * This code iterates through all the objects making sure that they are rooted.
4289  * Any unrooted objects are re-rooted in lost+found.
4290  * An object needs to be in one of:
4291  * - Directly under deleted, unlinked
4292  * - Directly or indirectly under root.
4293  *
4294  * Note:
4295  *  This code assumes that we don't ever change the current relationships
4296  *  between directories:
4297  *   root_dir->parent == unlinked_dir->parent == del_dir->parent == NULL
4298  *   lost-n-found->parent == root_dir
4299  *
4300  * This fixes the problem where directories might have inadvertently been
4301  * deleted leaving the object "hanging" without being rooted in the
4302  * directory tree.
4303  */
4304
4305 static int yaffs_has_null_parent(struct yaffs_dev *dev, struct yaffs_obj *obj)
4306 {
4307         return (obj == dev->del_dir ||
4308                 obj == dev->unlinked_dir || obj == dev->root_dir);
4309 }
4310
4311 static void yaffs_fix_hanging_objs(struct yaffs_dev *dev)
4312 {
4313         struct yaffs_obj *obj;
4314         struct yaffs_obj *parent;
4315         int i;
4316         struct list_head *lh;
4317         struct list_head *n;
4318         int depth_limit;
4319         int hanging;
4320
4321         if (dev->read_only)
4322                 return;
4323
4324         /* Iterate through the objects in each hash entry,
4325          * looking at each object.
4326          * Make sure it is rooted.
4327          */
4328
4329         for (i = 0; i < YAFFS_NOBJECT_BUCKETS; i++) {
4330                 list_for_each_safe(lh, n, &dev->obj_bucket[i].list) {
4331                         obj = list_entry(lh, struct yaffs_obj, hash_link);
4332                         parent = obj->parent;
4333
4334                         if (yaffs_has_null_parent(dev, obj)) {
4335                                 /* These directories are not hanging */
4336                                 hanging = 0;
4337                         } else if (!parent ||
4338                                    parent->variant_type !=
4339                                    YAFFS_OBJECT_TYPE_DIRECTORY) {
4340                                 hanging = 1;
4341                         } else if (yaffs_has_null_parent(dev, parent)) {
4342                                 hanging = 0;
4343                         } else {
4344                                 /*
4345                                  * Need to follow the parent chain to
4346                                  * see if it is hanging.
4347                                  */
4348                                 hanging = 0;
4349                                 depth_limit = 100;
4350
4351                                 while (parent != dev->root_dir &&
4352                                        parent->parent &&
4353                                        parent->parent->variant_type ==
4354                                        YAFFS_OBJECT_TYPE_DIRECTORY &&
4355                                        depth_limit > 0) {
4356                                         parent = parent->parent;
4357                                         depth_limit--;
4358                                 }
4359                                 if (parent != dev->root_dir)
4360                                         hanging = 1;
4361                         }
4362                         if (hanging) {
4363                                 yaffs_trace(YAFFS_TRACE_SCAN,
4364                                         "Hanging object %d moved to lost and found",
4365                                         obj->obj_id);
4366                                 yaffs_add_obj_to_dir(dev->lost_n_found, obj);
4367                         }
4368                 }
4369         }
4370 }
4371
4372 /*
4373  * Delete directory contents for cleaning up lost and found.
4374  */
4375 static void yaffs_del_dir_contents(struct yaffs_obj *dir)
4376 {
4377         struct yaffs_obj *obj;
4378         struct list_head *lh;
4379         struct list_head *n;
4380
4381         if (dir->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
4382                 BUG();
4383
4384         list_for_each_safe(lh, n, &dir->variant.dir_variant.children) {
4385                 obj = list_entry(lh, struct yaffs_obj, siblings);
4386                 if (obj->variant_type == YAFFS_OBJECT_TYPE_DIRECTORY)
4387                         yaffs_del_dir_contents(obj);
4388                 yaffs_trace(YAFFS_TRACE_SCAN,
4389                         "Deleting lost_found object %d",
4390                         obj->obj_id);
4391                 yaffs_unlink_obj(obj);
4392         }
4393 }
4394
4395 static void yaffs_empty_l_n_f(struct yaffs_dev *dev)
4396 {
4397         yaffs_del_dir_contents(dev->lost_n_found);
4398 }
4399
4400
4401 struct yaffs_obj *yaffs_find_by_name(struct yaffs_obj *directory,
4402                                      const YCHAR *name)
4403 {
4404         int sum;
4405         struct list_head *i;
4406         YCHAR buffer[YAFFS_MAX_NAME_LENGTH + 1];
4407         struct yaffs_obj *l;
4408
4409         if (!name)
4410                 return NULL;
4411
4412         if (!directory) {
4413                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4414                         "tragedy: yaffs_find_by_name: null pointer directory"
4415                         );
4416                 BUG();
4417                 return NULL;
4418         }
4419         if (directory->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY) {
4420                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4421                         "tragedy: yaffs_find_by_name: non-directory"
4422                         );
4423                 BUG();
4424         }
4425
4426         sum = yaffs_calc_name_sum(name);
4427
4428         list_for_each(i, &directory->variant.dir_variant.children) {
4429                 l = list_entry(i, struct yaffs_obj, siblings);
4430
4431                 if (l->parent != directory)
4432                         BUG();
4433
4434                 yaffs_check_obj_details_loaded(l);
4435
4436                 /* Special case for lost-n-found */
4437                 if (l->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4438                         if (!yaffs_strcmp(name, YAFFS_LOSTNFOUND_NAME))
4439                                 return l;
4440                 } else if (l->sum == sum || l->hdr_chunk <= 0) {
4441                         /* LostnFound chunk called Objxxx
4442                          * Do a real check
4443                          */
4444                         yaffs_get_obj_name(l, buffer,
4445                                 YAFFS_MAX_NAME_LENGTH + 1);
4446                         if (!yaffs_strncmp(name, buffer, YAFFS_MAX_NAME_LENGTH))
4447                                 return l;
4448                 }
4449         }
4450         return NULL;
4451 }
4452
4453 /* GetEquivalentObject dereferences any hard links to get to the
4454  * actual object.
4455  */
4456
4457 struct yaffs_obj *yaffs_get_equivalent_obj(struct yaffs_obj *obj)
4458 {
4459         if (obj && obj->variant_type == YAFFS_OBJECT_TYPE_HARDLINK) {
4460                 obj = obj->variant.hardlink_variant.equiv_obj;
4461                 yaffs_check_obj_details_loaded(obj);
4462         }
4463         return obj;
4464 }
4465
4466 /*
4467  *  A note or two on object names.
4468  *  * If the object name is missing, we then make one up in the form objnnn
4469  *
4470  *  * ASCII names are stored in the object header's name field from byte zero
4471  *  * Unicode names are historically stored starting from byte zero.
4472  *
4473  * Then there are automatic Unicode names...
4474  * The purpose of these is to save names in a way that can be read as
4475  * ASCII or Unicode names as appropriate, thus allowing a Unicode and ASCII
4476  * system to share files.
4477  *
4478  * These automatic unicode are stored slightly differently...
4479  *  - If the name can fit in the ASCII character space then they are saved as
4480  *    ascii names as per above.
4481  *  - If the name needs Unicode then the name is saved in Unicode
4482  *    starting at oh->name[1].
4483
4484  */
4485 static void yaffs_fix_null_name(struct yaffs_obj *obj, YCHAR *name,
4486                                 int buffer_size)
4487 {
4488         /* Create an object name if we could not find one. */
4489         if (yaffs_strnlen(name, YAFFS_MAX_NAME_LENGTH) == 0) {
4490                 YCHAR local_name[20];
4491                 YCHAR num_string[20];
4492                 YCHAR *x = &num_string[19];
4493                 unsigned v = obj->obj_id;
4494                 num_string[19] = 0;
4495                 while (v > 0) {
4496                         x--;
4497                         *x = '0' + (v % 10);
4498                         v /= 10;
4499                 }
4500                 /* make up a name */
4501                 yaffs_strcpy(local_name, YAFFS_LOSTNFOUND_PREFIX);
4502                 yaffs_strcat(local_name, x);
4503                 yaffs_strncpy(name, local_name, buffer_size - 1);
4504         }
4505 }
4506
4507 int yaffs_get_obj_name(struct yaffs_obj *obj, YCHAR *name, int buffer_size)
4508 {
4509         memset(name, 0, buffer_size * sizeof(YCHAR));
4510         yaffs_check_obj_details_loaded(obj);
4511         if (obj->obj_id == YAFFS_OBJECTID_LOSTNFOUND) {
4512                 yaffs_strncpy(name, YAFFS_LOSTNFOUND_NAME, buffer_size - 1);
4513         } else if (obj->short_name[0]) {
4514                 yaffs_strcpy(name, obj->short_name);
4515         } else if (obj->hdr_chunk > 0) {
4516                 //int result;
4517                 u8 *buffer = yaffs_get_temp_buffer(obj->my_dev);
4518
4519                 struct yaffs_obj_hdr *oh = (struct yaffs_obj_hdr *)buffer;
4520
4521                 memset(buffer, 0, obj->my_dev->data_bytes_per_chunk);
4522
4523                 if (obj->hdr_chunk > 0) {
4524                         if (!yaffs_rd_chunk_tags_nand(obj->my_dev,
4525                                                           obj->hdr_chunk,
4526                                                           buffer, NULL))
4527                         {
4528                             yaffs_trace(YAFFS_TRACE_ERROR,
4529                                         "yaffs_get_obj_name: unhandled error from rd_chunk_tags_nand");
4530                         }
4531                 }
4532                 yaffs_load_name_from_oh(obj->my_dev, name, oh->name,
4533                                         buffer_size);
4534
4535                 yaffs_release_temp_buffer(obj->my_dev, buffer);
4536         }
4537
4538         yaffs_fix_null_name(obj, name, buffer_size);
4539
4540         return yaffs_strnlen(name, YAFFS_MAX_NAME_LENGTH);
4541 }
4542
4543 Y_LOFF_T yaffs_get_obj_length(struct yaffs_obj *obj)
4544 {
4545         /* Dereference any hard linking */
4546         obj = yaffs_get_equivalent_obj(obj);
4547
4548         if (obj->variant_type == YAFFS_OBJECT_TYPE_FILE)
4549                 return obj->variant.file_variant.file_size;
4550         if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK) {
4551                 if (!obj->variant.symlink_variant.alias)
4552                         return 0;
4553                 return yaffs_strnlen(obj->variant.symlink_variant.alias,
4554                                      YAFFS_MAX_ALIAS_LENGTH);
4555         } else {
4556                 /* Only a directory should drop through to here */
4557                 return obj->my_dev->data_bytes_per_chunk;
4558         }
4559 }
4560
4561 int yaffs_get_obj_link_count(struct yaffs_obj *obj)
4562 {
4563         int count = 0;
4564         struct list_head *i;
4565
4566         if (!obj->unlinked)
4567                 count++;        /* the object itself */
4568
4569         list_for_each(i, &obj->hard_links)
4570             count++;            /* add the hard links; */
4571
4572         return count;
4573 }
4574
4575 int yaffs_get_obj_inode(struct yaffs_obj *obj)
4576 {
4577         obj = yaffs_get_equivalent_obj(obj);
4578
4579         return obj->obj_id;
4580 }
4581
4582 unsigned yaffs_get_obj_type(struct yaffs_obj *obj)
4583 {
4584         obj = yaffs_get_equivalent_obj(obj);
4585
4586         switch (obj->variant_type) {
4587         case YAFFS_OBJECT_TYPE_FILE:
4588                 return DT_REG;
4589                 break;
4590         case YAFFS_OBJECT_TYPE_DIRECTORY:
4591                 return DT_DIR;
4592                 break;
4593         case YAFFS_OBJECT_TYPE_SYMLINK:
4594                 return DT_LNK;
4595                 break;
4596         case YAFFS_OBJECT_TYPE_HARDLINK:
4597                 return DT_REG;
4598                 break;
4599         case YAFFS_OBJECT_TYPE_SPECIAL:
4600                 if (S_ISFIFO(obj->yst_mode))
4601                         return DT_FIFO;
4602                 if (S_ISCHR(obj->yst_mode))
4603                         return DT_CHR;
4604                 if (S_ISBLK(obj->yst_mode))
4605                         return DT_BLK;
4606                 if (S_ISSOCK(obj->yst_mode))
4607                         return DT_SOCK;
4608                 return DT_REG;
4609                 break;
4610         default:
4611                 return DT_REG;
4612                 break;
4613         }
4614 }
4615
4616 YCHAR *yaffs_get_symlink_alias(struct yaffs_obj *obj)
4617 {
4618         obj = yaffs_get_equivalent_obj(obj);
4619         if (obj->variant_type == YAFFS_OBJECT_TYPE_SYMLINK)
4620                 return yaffs_clone_str(obj->variant.symlink_variant.alias);
4621         else
4622                 return yaffs_clone_str(_Y(""));
4623 }
4624
4625 /*--------------------------- Initialisation code -------------------------- */
4626
4627 static int yaffs_check_dev_fns(struct yaffs_dev *dev)
4628 {
4629         struct yaffs_driver *drv = &dev->drv;
4630         struct yaffs_tags_handler *tagger = &dev->tagger;
4631
4632         /* Common functions, gotta have */
4633         if (!drv->drv_read_chunk_fn ||
4634             !drv->drv_write_chunk_fn ||
4635             !drv->drv_erase_fn)
4636                 return 0;
4637
4638         if (dev->param.is_yaffs2 &&
4639              (!drv->drv_mark_bad_fn  || !drv->drv_check_bad_fn))
4640                 return 0;
4641
4642         /* Install the default tags marshalling functions if needed. */
4643         yaffs_tags_compat_install(dev);
4644         yaffs_tags_marshall_install(dev);
4645
4646         /* Check we now have the marshalling functions required. */
4647         if (!tagger->write_chunk_tags_fn ||
4648             !tagger->read_chunk_tags_fn ||
4649             !tagger->query_block_fn ||
4650             !tagger->mark_bad_fn)
4651                 return 0;
4652
4653         return 1;
4654 }
4655
4656 static int yaffs_create_initial_dir(struct yaffs_dev *dev)
4657 {
4658         /* Initialise the unlinked, deleted, root and lost+found directories */
4659         dev->lost_n_found = dev->root_dir = NULL;
4660         dev->unlinked_dir = dev->del_dir = NULL;
4661         dev->unlinked_dir =
4662             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_UNLINKED, S_IFDIR);
4663         dev->del_dir =
4664             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_DELETED, S_IFDIR);
4665         dev->root_dir =
4666             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_ROOT,
4667                                   YAFFS_ROOT_MODE | S_IFDIR);
4668         dev->lost_n_found =
4669             yaffs_create_fake_dir(dev, YAFFS_OBJECTID_LOSTNFOUND,
4670                                   YAFFS_LOSTNFOUND_MODE | S_IFDIR);
4671
4672         if (dev->lost_n_found && dev->root_dir && dev->unlinked_dir
4673             && dev->del_dir) {
4674                 yaffs_add_obj_to_dir(dev->root_dir, dev->lost_n_found);
4675                 return YAFFS_OK;
4676         }
4677         return YAFFS_FAIL;
4678 }
4679
4680 /* Low level init.
4681  * Typically only used by yaffs_guts_initialise, but also used by the
4682  * Low level yaffs driver tests.
4683  */
4684
4685 int yaffs_guts_ll_init(struct yaffs_dev *dev)
4686 {
4687
4688
4689         yaffs_trace(YAFFS_TRACE_TRACING, "yaffs: yaffs_ll_init()");
4690
4691         if (!dev) {
4692                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4693                         "yaffs: Need a device"
4694                         );
4695                 return YAFFS_FAIL;
4696         }
4697
4698         if (dev->ll_init)
4699                 return YAFFS_OK;
4700
4701         dev->internal_start_block = dev->param.start_block;
4702         dev->internal_end_block = dev->param.end_block;
4703         dev->block_offset = 0;
4704         dev->chunk_offset = 0;
4705         dev->n_free_chunks = 0;
4706
4707         dev->gc_block = 0;
4708
4709         if (dev->param.start_block == 0) {
4710                 dev->internal_start_block = dev->param.start_block + 1;
4711                 dev->internal_end_block = dev->param.end_block + 1;
4712                 dev->block_offset = 1;
4713                 dev->chunk_offset = dev->param.chunks_per_block;
4714         }
4715
4716         /* Check geometry parameters. */
4717
4718         if ((!dev->param.inband_tags && dev->param.is_yaffs2 &&
4719                 dev->param.total_bytes_per_chunk < 1024) ||
4720                 (!dev->param.is_yaffs2 &&
4721                         dev->param.total_bytes_per_chunk < 512) ||
4722                 (dev->param.inband_tags && !dev->param.is_yaffs2) ||
4723                  dev->param.chunks_per_block < 2 ||
4724                  dev->param.n_reserved_blocks < 2 ||
4725                 dev->internal_start_block <= 0 ||
4726                 dev->internal_end_block <= 0 ||
4727                 dev->internal_end_block <=
4728                 (dev->internal_start_block + dev->param.n_reserved_blocks + 2)
4729                 ) {
4730                 /* otherwise it is too small */
4731                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4732                         "NAND geometry problems: chunk size %d, type is yaffs%s, inband_tags %d ",
4733                         dev->param.total_bytes_per_chunk,
4734                         dev->param.is_yaffs2 ? "2" : "",
4735                         dev->param.inband_tags);
4736                 return YAFFS_FAIL;
4737         }
4738
4739         /* Sort out space for inband tags, if required */
4740         if (dev->param.inband_tags)
4741                 dev->data_bytes_per_chunk =
4742                     dev->param.total_bytes_per_chunk -
4743                     sizeof(struct yaffs_packed_tags2_tags_only);
4744         else
4745                 dev->data_bytes_per_chunk = dev->param.total_bytes_per_chunk;
4746
4747         /* Got the right mix of functions? */
4748         if (!yaffs_check_dev_fns(dev)) {
4749                 /* Function missing */
4750                 yaffs_trace(YAFFS_TRACE_ALWAYS,
4751                         "device function(s) missing or wrong");
4752
4753                 return YAFFS_FAIL;
4754         }
4755
4756         if (yaffs_init_nand(dev) != YAFFS_OK) {
4757                 yaffs_trace(YAFFS_TRACE_ALWAYS, "InitialiseNAND failed");
4758                 return YAFFS_FAIL;
4759         }
4760
4761         return YAFFS_OK;
4762 }
4763
4764
4765 int yaffs_guts_format_dev(struct yaffs_dev *dev)
4766 {
4767         int i;
4768         enum yaffs_block_state state;
4769         u32 dummy;
4770
4771         if(yaffs_guts_ll_init(dev) != YAFFS_OK)
4772                 return YAFFS_FAIL;
4773
4774         if(dev->is_mounted)
4775                 return YAFFS_FAIL;
4776
4777         for (i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
4778                 yaffs_query_init_block_state(dev, i, &state, &dummy);
4779                 if (state != YAFFS_BLOCK_STATE_DEAD)
4780                         yaffs_erase_block(dev, i);
4781         }
4782
4783         return YAFFS_OK;
4784 }
4785
4786
4787 int yaffs_guts_initialise(struct yaffs_dev *dev)
4788 {
4789         int init_failed = 0;
4790         unsigned x;
4791         int bits;
4792
4793         if(yaffs_guts_ll_init(dev) != YAFFS_OK)
4794                 return YAFFS_FAIL;
4795
4796         if (dev->is_mounted) {
4797                 yaffs_trace(YAFFS_TRACE_ALWAYS, "device already mounted");
4798                 return YAFFS_FAIL;
4799         }
4800
4801         dev->is_mounted = 1;
4802
4803         /* OK now calculate a few things for the device */
4804
4805         /*
4806          *  Calculate all the chunk size manipulation numbers:
4807          */
4808         x = dev->data_bytes_per_chunk;
4809         /* We always use dev->chunk_shift and dev->chunk_div */
4810         dev->chunk_shift = calc_shifts(x);
4811         x >>= dev->chunk_shift;
4812         dev->chunk_div = x;
4813         /* We only use chunk mask if chunk_div is 1 */
4814         dev->chunk_mask = (1 << dev->chunk_shift) - 1;
4815
4816         /*
4817          * Calculate chunk_grp_bits.
4818          * We need to find the next power of 2 > than internal_end_block
4819          */
4820
4821         x = dev->param.chunks_per_block * (dev->internal_end_block + 1);
4822
4823         bits = calc_shifts_ceiling(x);
4824
4825         /* Set up tnode width if wide tnodes are enabled. */
4826         if (!dev->param.wide_tnodes_disabled) {
4827                 /* bits must be even so that we end up with 32-bit words */
4828                 if (bits & 1)
4829                         bits++;
4830                 if (bits < 16)
4831                         dev->tnode_width = 16;
4832                 else
4833                         dev->tnode_width = bits;
4834         } else {
4835                 dev->tnode_width = 16;
4836         }
4837
4838         dev->tnode_mask = (1 << dev->tnode_width) - 1;
4839
4840         /* Level0 Tnodes are 16 bits or wider (if wide tnodes are enabled),
4841          * so if the bitwidth of the
4842          * chunk range we're using is greater than 16 we need
4843          * to figure out chunk shift and chunk_grp_size
4844          */
4845
4846         if (bits <= (int)dev->tnode_width)
4847                 dev->chunk_grp_bits = 0;
4848         else
4849                 dev->chunk_grp_bits = bits - dev->tnode_width;
4850
4851         dev->tnode_size = (dev->tnode_width * YAFFS_NTNODES_LEVEL0) / 8;
4852         if (dev->tnode_size < sizeof(struct yaffs_tnode))
4853                 dev->tnode_size = sizeof(struct yaffs_tnode);
4854
4855         dev->chunk_grp_size = 1 << dev->chunk_grp_bits;
4856
4857         if (dev->param.chunks_per_block < dev->chunk_grp_size) {
4858                 /* We have a problem because the soft delete won't work if
4859                  * the chunk group size > chunks per block.
4860                  * This can be remedied by using larger "virtual blocks".
4861                  */
4862                 yaffs_trace(YAFFS_TRACE_ALWAYS, "chunk group too large");
4863
4864                 return YAFFS_FAIL;
4865         }
4866
4867         /* Finished verifying the device, continue with initialisation */
4868
4869         /* More device initialisation */
4870         dev->all_gcs = 0;
4871         dev->passive_gc_count = 0;
4872         dev->oldest_dirty_gc_count = 0;
4873         dev->bg_gcs = 0;
4874         dev->gc_block_finder = 0;
4875         dev->buffered_block = -1;
4876         dev->doing_buffered_block_rewrite = 0;
4877         dev->n_deleted_files = 0;
4878         dev->n_bg_deletions = 0;
4879         dev->n_unlinked_files = 0;
4880         dev->n_ecc_fixed = 0;
4881         dev->n_ecc_unfixed = 0;
4882         dev->n_tags_ecc_fixed = 0;
4883         dev->n_tags_ecc_unfixed = 0;
4884         dev->n_erase_failures = 0;
4885         dev->n_erased_blocks = 0;
4886         dev->gc_disable = 0;
4887         dev->has_pending_prioritised_gc = 1;
4888                 /* Assume the worst for now, will get fixed on first GC */
4889         INIT_LIST_HEAD(&dev->dirty_dirs);
4890         dev->oldest_dirty_seq = 0;
4891         dev->oldest_dirty_block = 0;
4892
4893         /* Initialise temporary buffers and caches. */
4894         if (!yaffs_init_tmp_buffers(dev))
4895                 init_failed = 1;
4896
4897         dev->cache = NULL;
4898         dev->gc_cleanup_list = NULL;
4899
4900         if (!init_failed && dev->param.n_caches > 0) {
4901                 int i;
4902                 void *buf;
4903                 int cache_bytes =
4904                     dev->param.n_caches * sizeof(struct yaffs_cache);
4905
4906                 if (dev->param.n_caches > YAFFS_MAX_SHORT_OP_CACHES)
4907                         dev->param.n_caches = YAFFS_MAX_SHORT_OP_CACHES;
4908
4909                 dev->cache = kmalloc(cache_bytes, GFP_NOFS);
4910
4911                 buf = (u8 *) dev->cache;
4912
4913                 if (dev->cache)
4914                         memset(dev->cache, 0, cache_bytes);
4915
4916                 for (i = 0; i < dev->param.n_caches && buf; i++) {
4917                         dev->cache[i].object = NULL;
4918                         dev->cache[i].last_use = 0;
4919                         dev->cache[i].dirty = 0;
4920                         dev->cache[i].data = buf =
4921                             kmalloc(dev->param.total_bytes_per_chunk, GFP_NOFS);
4922                 }
4923                 if (!buf)
4924                         init_failed = 1;
4925
4926                 dev->cache_last_use = 0;
4927         }
4928
4929         dev->cache_hits = 0;
4930
4931         if (!init_failed) {
4932                 dev->gc_cleanup_list =
4933                     kmalloc(dev->param.chunks_per_block * sizeof(u32),
4934                                         GFP_NOFS);
4935                 if (!dev->gc_cleanup_list)
4936                         init_failed = 1;
4937         }
4938
4939         if (dev->param.is_yaffs2)
4940                 dev->param.use_header_file_size = 1;
4941
4942         if (!init_failed && !yaffs_init_blocks(dev))
4943                 init_failed = 1;
4944
4945         yaffs_init_tnodes_and_objs(dev);
4946
4947         if (!init_failed && !yaffs_create_initial_dir(dev))
4948                 init_failed = 1;
4949
4950         if (!init_failed && dev->param.is_yaffs2 &&
4951                 !dev->param.disable_summary &&
4952                 !yaffs_summary_init(dev))
4953                 init_failed = 1;
4954
4955         if (!init_failed) {
4956                 /* Now scan the flash. */
4957                 if (dev->param.is_yaffs2) {
4958                         if (yaffs2_checkpt_restore(dev)) {
4959                                 yaffs_check_obj_details_loaded(dev->root_dir);
4960                                 yaffs_trace(YAFFS_TRACE_CHECKPOINT |
4961                                         YAFFS_TRACE_MOUNT,
4962                                         "yaffs: restored from checkpoint"
4963                                         );
4964                         } else {
4965
4966                                 /* Clean up the mess caused by an aborted
4967                                  * checkpoint load then scan backwards.
4968                                  */
4969                                 yaffs_deinit_blocks(dev);
4970
4971                                 yaffs_deinit_tnodes_and_objs(dev);
4972
4973                                 dev->n_erased_blocks = 0;
4974                                 dev->n_free_chunks = 0;
4975                                 dev->alloc_block = -1;
4976                                 dev->alloc_page = -1;
4977                                 dev->n_deleted_files = 0;
4978                                 dev->n_unlinked_files = 0;
4979                                 dev->n_bg_deletions = 0;
4980
4981                                 if (!init_failed && !yaffs_init_blocks(dev))
4982                                         init_failed = 1;
4983
4984                                 yaffs_init_tnodes_and_objs(dev);
4985
4986                                 if (!init_failed
4987                                     && !yaffs_create_initial_dir(dev))
4988                                         init_failed = 1;
4989
4990                                 if (!init_failed && !yaffs2_scan_backwards(dev))
4991                                         init_failed = 1;
4992                         }
4993                 } else if (!yaffs1_scan(dev)) {
4994                         init_failed = 1;
4995                 }
4996
4997                 yaffs_strip_deleted_objs(dev);
4998                 yaffs_fix_hanging_objs(dev);
4999                 if (dev->param.empty_lost_n_found)
5000                         yaffs_empty_l_n_f(dev);
5001         }
5002
5003         if (init_failed) {
5004                 /* Clean up the mess */
5005                 yaffs_trace(YAFFS_TRACE_TRACING,
5006                   "yaffs: yaffs_guts_initialise() aborted.");
5007
5008                 yaffs_deinitialise(dev);
5009                 return YAFFS_FAIL;
5010         }
5011
5012         /* Zero out stats */
5013         dev->n_page_reads = 0;
5014         dev->n_page_writes = 0;
5015         dev->n_erasures = 0;
5016         dev->n_gc_copies = 0;
5017         dev->n_retried_writes = 0;
5018
5019         dev->n_retired_blocks = 0;
5020
5021         yaffs_verify_free_chunks(dev);
5022         yaffs_verify_blocks(dev);
5023
5024         /* Clean up any aborted checkpoint data */
5025         if (!dev->is_checkpointed && dev->blocks_in_checkpt > 0)
5026                 yaffs2_checkpt_invalidate(dev);
5027
5028         yaffs_trace(YAFFS_TRACE_TRACING,
5029           "yaffs: yaffs_guts_initialise() done.");
5030         return YAFFS_OK;
5031 }
5032
5033 void yaffs_deinitialise(struct yaffs_dev *dev)
5034 {
5035         if (dev->is_mounted) {
5036                 int i;
5037
5038                 yaffs_deinit_blocks(dev);
5039                 yaffs_deinit_tnodes_and_objs(dev);
5040                 yaffs_summary_deinit(dev);
5041
5042                 if (dev->param.n_caches > 0 && dev->cache) {
5043
5044                         for (i = 0; i < dev->param.n_caches; i++) {
5045                                 kfree(dev->cache[i].data);
5046                                 dev->cache[i].data = NULL;
5047                         }
5048
5049                         kfree(dev->cache);
5050                         dev->cache = NULL;
5051                 }
5052
5053                 kfree(dev->gc_cleanup_list);
5054
5055                 for (i = 0; i < YAFFS_N_TEMP_BUFFERS; i++)
5056                         kfree(dev->temp_buffer[i].buffer);
5057
5058                 dev->is_mounted = 0;
5059
5060                 yaffs_deinit_nand(dev);
5061         }
5062 }
5063
5064 int yaffs_count_free_chunks(struct yaffs_dev *dev)
5065 {
5066         int n_free = 0;
5067         int b;
5068         struct yaffs_block_info *blk;
5069
5070         blk = dev->block_info;
5071         for (b = dev->internal_start_block; b <= dev->internal_end_block; b++) {
5072                 switch (blk->block_state) {
5073                 case YAFFS_BLOCK_STATE_EMPTY:
5074                 case YAFFS_BLOCK_STATE_ALLOCATING:
5075                 case YAFFS_BLOCK_STATE_COLLECTING:
5076                 case YAFFS_BLOCK_STATE_FULL:
5077                         n_free +=
5078                             (dev->param.chunks_per_block - blk->pages_in_use +
5079                              blk->soft_del_pages);
5080                         break;
5081                 default:
5082                         break;
5083                 }
5084                 blk++;
5085         }
5086         return n_free;
5087 }
5088
5089 int yaffs_get_n_free_chunks(struct yaffs_dev *dev)
5090 {
5091         /* This is what we report to the outside world */
5092         int n_free;
5093         int n_dirty_caches;
5094         int blocks_for_checkpt;
5095         int i;
5096
5097         n_free = dev->n_free_chunks;
5098         n_free += dev->n_deleted_files;
5099
5100         /* Now count and subtract the number of dirty chunks in the cache. */
5101
5102         for (n_dirty_caches = 0, i = 0; i < dev->param.n_caches; i++) {
5103                 if (dev->cache[i].dirty)
5104                         n_dirty_caches++;
5105         }
5106
5107         n_free -= n_dirty_caches;
5108
5109         n_free -=
5110             ((dev->param.n_reserved_blocks + 1) * dev->param.chunks_per_block);
5111
5112         /* Now figure checkpoint space and report that... */
5113         blocks_for_checkpt = yaffs_calc_checkpt_blocks_required(dev);
5114
5115         n_free -= (blocks_for_checkpt * dev->param.chunks_per_block);
5116
5117         if (n_free < 0)
5118                 n_free = 0;
5119
5120         return n_free;
5121 }
5122
5123
5124
5125 /*
5126  * Marshalling functions to get Y_LOFF_T file sizes into and out of
5127  * object headers.
5128  */
5129 void yaffs_oh_size_load(struct yaffs_obj_hdr *oh, Y_LOFF_T fsize)
5130 {
5131 #ifdef CONFIG_YAFFS_OP
5132         oh->file_size_low = (fsize & 0xFFFFFFFF);
5133         oh->file_size_high = 0; //((fsize >> 32) & 0xFFFFFFFF);
5134 #else
5135         oh->file_size_low = (fsize & 0xFFFFFFFF);
5136         oh->file_size_high = ((fsize >> 32) & 0xFFFFFFFF);
5137 #endif
5138 }
5139
5140 Y_LOFF_T yaffs_oh_to_size(struct yaffs_obj_hdr *oh)
5141 {
5142         Y_LOFF_T retval;
5143
5144         if (sizeof(Y_LOFF_T) >= 8 && ~(oh->file_size_high))
5145 #ifdef CONFIG_YAFFS_OP
5146                 retval = (((Y_LOFF_T) oh->file_size_low) & 0xFFFFFFFF);
5147 #else
5148                 retval = (((Y_LOFF_T) oh->file_size_high) << 32) |
5149                         (((Y_LOFF_T) oh->file_size_low) & 0xFFFFFFFF);
5150 #endif
5151         else
5152                 retval = (Y_LOFF_T) oh->file_size_low;
5153
5154         return retval;
5155 }
5156
5157
5158 void yaffs_count_blocks_by_state(struct yaffs_dev *dev, int bs[10])
5159 {
5160         int i;
5161         struct yaffs_block_info *bi;
5162         int s;
5163
5164         for(i = 0; i < 10; i++)
5165                 bs[i] = 0;
5166
5167         for(i = dev->internal_start_block; i <= dev->internal_end_block; i++) {
5168                 bi = yaffs_get_block_info(dev, i);
5169                 s = bi->block_state;
5170                 if(s > YAFFS_BLOCK_STATE_DEAD || s < YAFFS_BLOCK_STATE_UNKNOWN)
5171                         bs[0]++;
5172                 else
5173                         bs[s]++;
5174         }
5175 }