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