fs/reiserfs/stree.c

   1 /*
   2  *  Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
   3  */
   4
   5 /*
   6  *  Written by Anatoly P. Pinchuk pap@namesys.botik.ru
   7  *  Programm System Institute
   8  *  Pereslavl-Zalessky Russia
   9  */
  10
  11 /*
  12  *  This file contains functions dealing with S+tree
  13  *
  14  * B_IS_IN_TREE
  15  * copy_item_head
  16  * comp_short_keys
  17  * comp_keys
  18  * comp_short_le_keys
  19  * le_key2cpu_key
  20  * comp_le_keys
  21  * bin_search
  22  * get_lkey
  23  * get_rkey
  24  * key_in_buffer
  25  * decrement_bcount
  26  * reiserfs_check_path
  27  * pathrelse_and_restore
  28  * pathrelse
  29  * search_by_key_reada
  30  * search_by_key
  31  * search_for_position_by_key
  32  * comp_items
  33  * prepare_for_direct_item
  34  * prepare_for_direntry_item
  35  * prepare_for_delete_or_cut
  36  * calc_deleted_bytes_number
  37  * init_tb_struct
  38  * padd_item
  39  * reiserfs_delete_item
  40  * reiserfs_delete_solid_item
  41  * reiserfs_delete_object
  42  * maybe_indirect_to_direct
  43  * indirect_to_direct_roll_back
  44  * reiserfs_cut_from_item
  45  * truncate_directory
  46  * reiserfs_do_truncate
  47  * reiserfs_paste_into_item
  48  * reiserfs_insert_item
  49  */
  50
  51 #include <linux/time.h>
  52 #include <linux/string.h>
  53 #include <linux/pagemap.h>
  54 #include "reiserfs.h"
  55 #include <linux/buffer_head.h>
  56 #include <linux/quotaops.h>
  57
  58 /* Does the buffer contain a disk block which is in the tree. */
  59 inline int B_IS_IN_TREE(const struct buffer_head *bh)
  60 {
  61
  62         RFALSE(B_LEVEL(bh) > MAX_HEIGHT,
  63                "PAP-1010: block (%b) has too big level (%z)", bh, bh);
  64
  65         return (B_LEVEL(bh) != FREE_LEVEL);
  66 }
  67
  68 //
  69 // to gets item head in le form
  70 //
  71 inline void copy_item_head(struct item_head *to,
  72                            const struct item_head *from)
  73 {
  74         memcpy(to, from, IH_SIZE);
  75 }
  76
  77 /* k1 is pointer to on-disk structure which is stored in little-endian
  78    form. k2 is pointer to cpu variable. For key of items of the same
  79    object this returns 0.
  80    Returns: -1 if key1 < key2
  81    0 if key1 == key2
  82    1 if key1 > key2 */
  83 inline int comp_short_keys(const struct reiserfs_key *le_key,
  84                            const struct cpu_key *cpu_key)
  85 {
  86         __u32 n;
  87         n = le32_to_cpu(le_key->k_dir_id);
  88         if (n < cpu_key->on_disk_key.k_dir_id)
  89                 return -1;
  90         if (n > cpu_key->on_disk_key.k_dir_id)
  91                 return 1;
  92         n = le32_to_cpu(le_key->k_objectid);
  93         if (n < cpu_key->on_disk_key.k_objectid)
  94                 return -1;
  95         if (n > cpu_key->on_disk_key.k_objectid)
  96                 return 1;
  97         return 0;
  98 }
  99
 100 /* k1 is pointer to on-disk structure which is stored in little-endian
 101    form. k2 is pointer to cpu variable.
 102    Compare keys using all 4 key fields.
 103    Returns: -1 if key1 < key2 0
 104    if key1 = key2 1 if key1 > key2 */
 105 static inline int comp_keys(const struct reiserfs_key *le_key,
 106                             const struct cpu_key *cpu_key)
 107 {
 108         int retval;
 109
 110         retval = comp_short_keys(le_key, cpu_key);
 111         if (retval)
 112                 return retval;
 113         if (le_key_k_offset(le_key_version(le_key), le_key) <
 114             cpu_key_k_offset(cpu_key))
 115                 return -1;
 116         if (le_key_k_offset(le_key_version(le_key), le_key) >
 117             cpu_key_k_offset(cpu_key))
 118                 return 1;
 119
 120         if (cpu_key->key_length == 3)
 121                 return 0;
 122
 123         /* this part is needed only when tail conversion is in progress */
 124         if (le_key_k_type(le_key_version(le_key), le_key) <
 125             cpu_key_k_type(cpu_key))
 126                 return -1;
 127
 128         if (le_key_k_type(le_key_version(le_key), le_key) >
 129             cpu_key_k_type(cpu_key))
 130                 return 1;
 131
 132         return 0;
 133 }
 134
 135 inline int comp_short_le_keys(const struct reiserfs_key *key1,
 136                               const struct reiserfs_key *key2)
 137 {
 138         __u32 *k1_u32, *k2_u32;
 139         int key_length = REISERFS_SHORT_KEY_LEN;
 140
 141         k1_u32 = (__u32 *) key1;
 142         k2_u32 = (__u32 *) key2;
 143         for (; key_length--; ++k1_u32, ++k2_u32) {
 144                 if (le32_to_cpu(*k1_u32) < le32_to_cpu(*k2_u32))
 145                         return -1;
 146                 if (le32_to_cpu(*k1_u32) > le32_to_cpu(*k2_u32))
 147                         return 1;
 148         }
 149         return 0;
 150 }
 151
 152 inline void le_key2cpu_key(struct cpu_key *to, const struct reiserfs_key *from)
 153 {
 154         int version;
 155         to->on_disk_key.k_dir_id = le32_to_cpu(from->k_dir_id);
 156         to->on_disk_key.k_objectid = le32_to_cpu(from->k_objectid);
 157
 158         // find out version of the key
 159         version = le_key_version(from);
 160         to->version = version;
 161         to->on_disk_key.k_offset = le_key_k_offset(version, from);
 162         to->on_disk_key.k_type = le_key_k_type(version, from);
 163 }
 164
 165 // this does not say which one is bigger, it only returns 1 if keys
 166 // are not equal, 0 otherwise
 167 inline int comp_le_keys(const struct reiserfs_key *k1,
 168                         const struct reiserfs_key *k2)
 169 {
 170         return memcmp(k1, k2, sizeof(struct reiserfs_key));
 171 }
 172
 173 /**************************************************************************
 174  *  Binary search toolkit function                                        *
 175  *  Search for an item in the array by the item key                       *
 176  *  Returns:    1 if found,  0 if not found;                              *
 177  *        *pos = number of the searched element if found, else the        *
 178  *        number of the first element that is larger than key.            *
 179  **************************************************************************/
 180 /* For those not familiar with binary search: lbound is the leftmost item that it
 181  could be, rbound the rightmost item that it could be.  We examine the item
 182  halfway between lbound and rbound, and that tells us either that we can increase
 183  lbound, or decrease rbound, or that we have found it, or if lbound <= rbound that
 184  there are no possible items, and we have not found it. With each examination we
 185  cut the number of possible items it could be by one more than half rounded down,
 186  or we find it. */
 187 static inline int bin_search(const void *key,   /* Key to search for. */
 188                              const void *base,  /* First item in the array. */
 189                              int num,   /* Number of items in the array. */
 190                              int width, /* Item size in the array.
 191                                            searched. Lest the reader be
 192                                            confused, note that this is crafted
 193                                            as a general function, and when it
 194                                            is applied specifically to the array
 195                                            of item headers in a node, width
 196                                            is actually the item header size not
 197                                            the item size. */
 198                              int *pos /* Number of the searched for element. */
 199     )
 200 {
 201         int rbound, lbound, j;
 202
 203         for (j = ((rbound = num - 1) + (lbound = 0)) / 2;
 204              lbound <= rbound; j = (rbound + lbound) / 2)
 205                 switch (comp_keys
 206                         ((struct reiserfs_key *)((char *)base + j * width),
 207                          (struct cpu_key *)key)) {
 208                 case -1:
 209                         lbound = j + 1;
 210                         continue;
 211                 case 1:
 212                         rbound = j - 1;
 213                         continue;
 214                 case 0:
 215                         *pos = j;
 216                         return ITEM_FOUND;      /* Key found in the array.  */
 217                 }
 218
 219         /* bin_search did not find given key, it returns position of key,
 220            that is minimal and greater than the given one. */
 221         *pos = lbound;
 222         return ITEM_NOT_FOUND;
 223 }
 224
 225
 226 /* Minimal possible key. It is never in the tree. */
 227 const struct reiserfs_key MIN_KEY = { 0, 0, {{0, 0},} };
 228
 229 /* Maximal possible key. It is never in the tree. */
 230 static const struct reiserfs_key MAX_KEY = {
 231         __constant_cpu_to_le32(0xffffffff),
 232         __constant_cpu_to_le32(0xffffffff),
 233         {{__constant_cpu_to_le32(0xffffffff),
 234           __constant_cpu_to_le32(0xffffffff)},}
 235 };
 236
 237 /* Get delimiting key of the buffer by looking for it in the buffers in the path, starting from the bottom
 238    of the path, and going upwards.  We must check the path's validity at each step.  If the key is not in
 239    the path, there is no delimiting key in the tree (buffer is first or last buffer in tree), and in this
 240    case we return a special key, either MIN_KEY or MAX_KEY. */
 241 static inline const struct reiserfs_key *get_lkey(const struct treepath *chk_path,
 242                                                   const struct super_block *sb)
 243 {
 244         int position, path_offset = chk_path->path_length;
 245         struct buffer_head *parent;
 246
 247         RFALSE(path_offset < FIRST_PATH_ELEMENT_OFFSET,
 248                "PAP-5010: invalid offset in the path");
 249
 250         /* While not higher in path than first element. */
 251         while (path_offset-- > FIRST_PATH_ELEMENT_OFFSET) {
 252
 253                 RFALSE(!buffer_uptodate
 254                        (PATH_OFFSET_PBUFFER(chk_path, path_offset)),
 255                        "PAP-5020: parent is not uptodate");
 256
 257                 /* Parent at the path is not in the tree now. */
 258                 if (!B_IS_IN_TREE
 259                     (parent =
 260                      PATH_OFFSET_PBUFFER(chk_path, path_offset)))
 261                         return &MAX_KEY;
 262                 /* Check whether position in the parent is correct. */
 263                 if ((position =
 264                      PATH_OFFSET_POSITION(chk_path,
 265                                           path_offset)) >
 266                     B_NR_ITEMS(parent))
 267                         return &MAX_KEY;
 268                 /* Check whether parent at the path really points to the child. */
 269                 if (B_N_CHILD_NUM(parent, position) !=
 270                     PATH_OFFSET_PBUFFER(chk_path,
 271                                         path_offset + 1)->b_blocknr)
 272                         return &MAX_KEY;
 273                 /* Return delimiting key if position in the parent is not equal to zero. */
 274                 if (position)
 275                         return B_N_PDELIM_KEY(parent, position - 1);
 276         }
 277         /* Return MIN_KEY if we are in the root of the buffer tree. */
 278         if (PATH_OFFSET_PBUFFER(chk_path, FIRST_PATH_ELEMENT_OFFSET)->
 279             b_blocknr == SB_ROOT_BLOCK(sb))
 280                 return &MIN_KEY;
 281         return &MAX_KEY;
 282 }
 283
 284 /* Get delimiting key of the buffer at the path and its right neighbor. */
 285 inline const struct reiserfs_key *get_rkey(const struct treepath *chk_path,
 286                                            const struct super_block *sb)
 287 {
 288         int position, path_offset = chk_path->path_length;
 289         struct buffer_head *parent;
 290
 291         RFALSE(path_offset < FIRST_PATH_ELEMENT_OFFSET,
 292                "PAP-5030: invalid offset in the path");
 293
 294         while (path_offset-- > FIRST_PATH_ELEMENT_OFFSET) {
 295
 296                 RFALSE(!buffer_uptodate
 297                        (PATH_OFFSET_PBUFFER(chk_path, path_offset)),
 298                        "PAP-5040: parent is not uptodate");
 299
 300                 /* Parent at the path is not in the tree now. */
 301                 if (!B_IS_IN_TREE
 302                     (parent =
 303                      PATH_OFFSET_PBUFFER(chk_path, path_offset)))
 304                         return &MIN_KEY;
 305                 /* Check whether position in the parent is correct. */
 306                 if ((position =
 307                      PATH_OFFSET_POSITION(chk_path,
 308                                           path_offset)) >
 309                     B_NR_ITEMS(parent))
 310                         return &MIN_KEY;
 311                 /* Check whether parent at the path really points to the child. */
 312                 if (B_N_CHILD_NUM(parent, position) !=
 313                     PATH_OFFSET_PBUFFER(chk_path,
 314                                         path_offset + 1)->b_blocknr)
 315                         return &MIN_KEY;
 316                 /* Return delimiting key if position in the parent is not the last one. */
 317                 if (position != B_NR_ITEMS(parent))
 318                         return B_N_PDELIM_KEY(parent, position);
 319         }
 320         /* Return MAX_KEY if we are in the root of the buffer tree. */
 321         if (PATH_OFFSET_PBUFFER(chk_path, FIRST_PATH_ELEMENT_OFFSET)->
 322             b_blocknr == SB_ROOT_BLOCK(sb))
 323                 return &MAX_KEY;
 324         return &MIN_KEY;
 325 }
 326
 327 /* Check whether a key is contained in the tree rooted from a buffer at a path. */
 328 /* This works by looking at the left and right delimiting keys for the buffer in the last path_element in
 329    the path.  These delimiting keys are stored at least one level above that buffer in the tree. If the
 330    buffer is the first or last node in the tree order then one of the delimiting keys may be absent, and in
 331    this case get_lkey and get_rkey return a special key which is MIN_KEY or MAX_KEY. */
 332 static inline int key_in_buffer(struct treepath *chk_path,      /* Path which should be checked.  */
 333                                 const struct cpu_key *key,      /* Key which should be checked.   */
 334                                 struct super_block *sb
 335     )
 336 {
 337
 338         RFALSE(!key || chk_path->path_length < FIRST_PATH_ELEMENT_OFFSET
 339                || chk_path->path_length > MAX_HEIGHT,
 340                "PAP-5050: pointer to the key(%p) is NULL or invalid path length(%d)",
 341                key, chk_path->path_length);
 342         RFALSE(!PATH_PLAST_BUFFER(chk_path)->b_bdev,
 343                "PAP-5060: device must not be NODEV");
 344
 345         if (comp_keys(get_lkey(chk_path, sb), key) == 1)
 346                 /* left delimiting key is bigger, that the key we look for */
 347                 return 0;
 348         /*  if ( comp_keys(key, get_rkey(chk_path, sb)) != -1 ) */
 349         if (comp_keys(get_rkey(chk_path, sb), key) != 1)
 350                 /* key must be less than right delimitiing key */
 351                 return 0;
 352         return 1;
 353 }
 354
 355 int reiserfs_check_path(struct treepath *p)
 356 {
 357         RFALSE(p->path_length != ILLEGAL_PATH_ELEMENT_OFFSET,
 358                "path not properly relsed");
 359         return 0;
 360 }
 361
 362 /* Drop the reference to each buffer in a path and restore
 363  * dirty bits clean when preparing the buffer for the log.
 364  * This version should only be called from fix_nodes() */
 365 void pathrelse_and_restore(struct super_block *sb,
 366                            struct treepath *search_path)
 367 {
 368         int path_offset = search_path->path_length;
 369
 370         RFALSE(path_offset < ILLEGAL_PATH_ELEMENT_OFFSET,
 371                "clm-4000: invalid path offset");
 372
 373         while (path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) {
 374                 struct buffer_head *bh;
 375                 bh = PATH_OFFSET_PBUFFER(search_path, path_offset--);
 376                 reiserfs_restore_prepared_buffer(sb, bh);
 377                 brelse(bh);
 378         }
 379         search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
 380 }
 381
 382 /* Drop the reference to each buffer in a path */
 383 void pathrelse(struct treepath *search_path)
 384 {
 385         int path_offset = search_path->path_length;
 386
 387         RFALSE(path_offset < ILLEGAL_PATH_ELEMENT_OFFSET,
 388                "PAP-5090: invalid path offset");
 389
 390         while (path_offset > ILLEGAL_PATH_ELEMENT_OFFSET)
 391                 brelse(PATH_OFFSET_PBUFFER(search_path, path_offset--));
 392
 393         search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
 394 }
 395
 396 static int is_leaf(char *buf, int blocksize, struct buffer_head *bh)
 397 {
 398         struct block_head *blkh;
 399         struct item_head *ih;
 400         int used_space;
 401         int prev_location;
 402         int i;
 403         int nr;
 404
 405         blkh = (struct block_head *)buf;
 406         if (blkh_level(blkh) != DISK_LEAF_NODE_LEVEL) {
 407                 reiserfs_warning(NULL, "reiserfs-5080",
 408                                  "this should be caught earlier");
 409                 return 0;
 410         }
 411
 412         nr = blkh_nr_item(blkh);
 413         if (nr < 1 || nr > ((blocksize - BLKH_SIZE) / (IH_SIZE + MIN_ITEM_LEN))) {
 414                 /* item number is too big or too small */
 415                 reiserfs_warning(NULL, "reiserfs-5081",
 416                                  "nr_item seems wrong: %z", bh);
 417                 return 0;
 418         }
 419         ih = (struct item_head *)(buf + BLKH_SIZE) + nr - 1;
 420         used_space = BLKH_SIZE + IH_SIZE * nr + (blocksize - ih_location(ih));
 421         if (used_space != blocksize - blkh_free_space(blkh)) {
 422                 /* free space does not match to calculated amount of use space */
 423                 reiserfs_warning(NULL, "reiserfs-5082",
 424                                  "free space seems wrong: %z", bh);
 425                 return 0;
 426         }
 427         // FIXME: it is_leaf will hit performance too much - we may have
 428         // return 1 here
 429
 430         /* check tables of item heads */
 431         ih = (struct item_head *)(buf + BLKH_SIZE);
 432         prev_location = blocksize;
 433         for (i = 0; i < nr; i++, ih++) {
 434                 if (le_ih_k_type(ih) == TYPE_ANY) {
 435                         reiserfs_warning(NULL, "reiserfs-5083",
 436                                          "wrong item type for item %h",
 437                                          ih);
 438                         return 0;
 439                 }
 440                 if (ih_location(ih) >= blocksize
 441                     || ih_location(ih) < IH_SIZE * nr) {
 442                         reiserfs_warning(NULL, "reiserfs-5084",
 443                                          "item location seems wrong: %h",
 444                                          ih);
 445                         return 0;
 446                 }
 447                 if (ih_item_len(ih) < 1
 448                     || ih_item_len(ih) > MAX_ITEM_LEN(blocksize)) {
 449                         reiserfs_warning(NULL, "reiserfs-5085",
 450                                          "item length seems wrong: %h",
 451                                          ih);
 452                         return 0;
 453                 }
 454                 if (prev_location - ih_location(ih) != ih_item_len(ih)) {
 455                         reiserfs_warning(NULL, "reiserfs-5086",
 456                                          "item location seems wrong "
 457                                          "(second one): %h", ih);
 458                         return 0;
 459                 }
 460                 prev_location = ih_location(ih);
 461         }
 462
 463         // one may imagine much more checks
 464         return 1;
 465 }
 466
 467 /* returns 1 if buf looks like an internal node, 0 otherwise */
 468 static int is_internal(char *buf, int blocksize, struct buffer_head *bh)
 469 {
 470         struct block_head *blkh;
 471         int nr;
 472         int used_space;
 473
 474         blkh = (struct block_head *)buf;
 475         nr = blkh_level(blkh);
 476         if (nr <= DISK_LEAF_NODE_LEVEL || nr > MAX_HEIGHT) {
 477                 /* this level is not possible for internal nodes */
 478                 reiserfs_warning(NULL, "reiserfs-5087",
 479                                  "this should be caught earlier");
 480                 return 0;
 481         }
 482
 483         nr = blkh_nr_item(blkh);
 484         if (nr > (blocksize - BLKH_SIZE - DC_SIZE) / (KEY_SIZE + DC_SIZE)) {
 485                 /* for internal which is not root we might check min number of keys */
 486                 reiserfs_warning(NULL, "reiserfs-5088",
 487                                  "number of key seems wrong: %z", bh);
 488                 return 0;
 489         }
 490
 491         used_space = BLKH_SIZE + KEY_SIZE * nr + DC_SIZE * (nr + 1);
 492         if (used_space != blocksize - blkh_free_space(blkh)) {
 493                 reiserfs_warning(NULL, "reiserfs-5089",
 494                                  "free space seems wrong: %z", bh);
 495                 return 0;
 496         }
 497         // one may imagine much more checks
 498         return 1;
 499 }
 500
 501 // make sure that bh contains formatted node of reiserfs tree of
 502 // 'level'-th level
 503 static int is_tree_node(struct buffer_head *bh, int level)
 504 {
 505         if (B_LEVEL(bh) != level) {
 506                 reiserfs_warning(NULL, "reiserfs-5090", "node level %d does "
 507                                  "not match to the expected one %d",
 508                                  B_LEVEL(bh), level);
 509                 return 0;
 510         }
 511         if (level == DISK_LEAF_NODE_LEVEL)
 512                 return is_leaf(bh->b_data, bh->b_size, bh);
 513
 514         return is_internal(bh->b_data, bh->b_size, bh);
 515 }
 516
 517 #define SEARCH_BY_KEY_READA 16
 518
 519 /*
 520  * The function is NOT SCHEDULE-SAFE!
 521  * It might unlock the write lock if we needed to wait for a block
 522  * to be read. Note that in this case it won't recover the lock to avoid
 523  * high contention resulting from too much lock requests, especially
 524  * the caller (search_by_key) will perform other schedule-unsafe
 525  * operations just after calling this function.
 526  *
 527  * @return true if we have unlocked
 528  */
 529 static bool search_by_key_reada(struct super_block *s,
 530                                 struct buffer_head **bh,
 531                                 b_blocknr_t *b, int num)
 532 {
 533         int i, j;
 534         bool unlocked = false;
 535
 536         for (i = 0; i < num; i++) {
 537                 bh[i] = sb_getblk(s, b[i]);
 538         }
 539         /*
 540          * We are going to read some blocks on which we
 541          * have a reference. It's safe, though we might be
 542          * reading blocks concurrently changed if we release
 543          * the lock. But it's still fine because we check later
 544          * if the tree changed
 545          */
 546         for (j = 0; j < i; j++) {
 547                 /*
 548                  * note, this needs attention if we are getting rid of the BKL
 549                  * you have to make sure the prepared bit isn't set on this buffer
 550                  */
 551                 if (!buffer_uptodate(bh[j])) {
 552                         if (!unlocked) {
 553                                 reiserfs_write_unlock(s);
 554                                 unlocked = true;
 555                         }
 556                         ll_rw_block(READA, 1, bh + j);
 557                 }
 558                 brelse(bh[j]);
 559         }
 560         return unlocked;
 561 }
 562
 563 /**************************************************************************
 564  * Algorithm   SearchByKey                                                *
 565  *             look for item in the Disk S+Tree by its key                *
 566  * Input:  sb   -  super block                                            *
 567  *         key  - pointer to the key to search                            *
 568  * Output: ITEM_FOUND, ITEM_NOT_FOUND or IO_ERROR                         *
 569  *         search_path - path from the root to the needed leaf            *
 570  **************************************************************************/
 571
 572 /* This function fills up the path from the root to the leaf as it
 573    descends the tree looking for the key.  It uses reiserfs_bread to
 574    try to find buffers in the cache given their block number.  If it
 575    does not find them in the cache it reads them from disk.  For each
 576    node search_by_key finds using reiserfs_bread it then uses
 577    bin_search to look through that node.  bin_search will find the
 578    position of the block_number of the next node if it is looking
 579    through an internal node.  If it is looking through a leaf node
 580    bin_search will find the position of the item which has key either
 581    equal to given key, or which is the maximal key less than the given
 582    key.  search_by_key returns a path that must be checked for the
 583    correctness of the top of the path but need not be checked for the
 584    correctness of the bottom of the path */
 585 /* The function is NOT SCHEDULE-SAFE! */
 586 int search_by_key(struct super_block *sb, const struct cpu_key *key,    /* Key to search. */
 587                   struct treepath *search_path,/* This structure was
 588                                                    allocated and initialized
 589                                                    by the calling
 590                                                    function. It is filled up
 591                                                    by this function.  */
 592                   int stop_level        /* How far down the tree to search. To
 593                                            stop at leaf level - set to
 594                                            DISK_LEAF_NODE_LEVEL */
 595     )
 596 {
 597         b_blocknr_t block_number;
 598         int expected_level;
 599         struct buffer_head *bh;
 600         struct path_element *last_element;
 601         int node_level, retval;
 602         int right_neighbor_of_leaf_node;
 603         int fs_gen;
 604         struct buffer_head *reada_bh[SEARCH_BY_KEY_READA];
 605         b_blocknr_t reada_blocks[SEARCH_BY_KEY_READA];
 606         int reada_count = 0;
 607
 608 #ifdef CONFIG_REISERFS_CHECK
 609         int repeat_counter = 0;
 610 #endif
 611
 612         PROC_INFO_INC(sb, search_by_key);
 613
 614         /* As we add each node to a path we increase its count.  This means that
 615            we must be careful to release all nodes in a path before we either
 616            discard the path struct or re-use the path struct, as we do here. */
 617
 618         pathrelse(search_path);
 619
 620         right_neighbor_of_leaf_node = 0;
 621
 622         /* With each iteration of this loop we search through the items in the
 623            current node, and calculate the next current node(next path element)
 624            for the next iteration of this loop.. */
 625         block_number = SB_ROOT_BLOCK(sb);
 626         expected_level = -1;
 627         while (1) {
 628
 629 #ifdef CONFIG_REISERFS_CHECK
 630                 if (!(++repeat_counter % 50000))
 631                         reiserfs_warning(sb, "PAP-5100",
 632                                          "%s: there were %d iterations of "
 633                                          "while loop looking for key %K",
 634                                          current->comm, repeat_counter,
 635                                          key);
 636 #endif
 637
 638                 /* prep path to have another element added to it. */
 639                 last_element =
 640                     PATH_OFFSET_PELEMENT(search_path,
 641                                          ++search_path->path_length);
 642                 fs_gen = get_generation(sb);
 643
 644                 /* Read the next tree node, and set the last element in the path to
 645                    have a pointer to it. */
 646                 if ((bh = last_element->pe_buffer =
 647                      sb_getblk(sb, block_number))) {
 648                         bool unlocked = false;
 649
 650                         if (!buffer_uptodate(bh) && reada_count > 1)
 651                                 /* may unlock the write lock */
 652                                 unlocked = search_by_key_reada(sb, reada_bh,
 653                                                     reada_blocks, reada_count);
 654                         /*
 655                          * If we haven't already unlocked the write lock,
 656                          * then we need to do that here before reading
 657                          * the current block
 658                          */
 659                         if (!buffer_uptodate(bh) && !unlocked) {
 660                                 reiserfs_write_unlock(sb);
 661                                 unlocked = true;
 662                         }
 663                         ll_rw_block(READ, 1, &bh);
 664                         wait_on_buffer(bh);
 665
 666                         if (unlocked)
 667                                 reiserfs_write_lock(sb);
 668                         if (!buffer_uptodate(bh))
 669                                 goto io_error;
 670                 } else {
 671                       io_error:
 672                         search_path->path_length--;
 673                         pathrelse(search_path);
 674                         return IO_ERROR;
 675                 }
 676                 reada_count = 0;
 677                 if (expected_level == -1)
 678                         expected_level = SB_TREE_HEIGHT(sb);
 679                 expected_level--;
 680
 681                 /* It is possible that schedule occurred. We must check whether the key
 682                    to search is still in the tree rooted from the current buffer. If
 683                    not then repeat search from the root. */
 684                 if (fs_changed(fs_gen, sb) &&
 685                     (!B_IS_IN_TREE(bh) ||
 686                      B_LEVEL(bh) != expected_level ||
 687                      !key_in_buffer(search_path, key, sb))) {
 688                         PROC_INFO_INC(sb, search_by_key_fs_changed);
 689                         PROC_INFO_INC(sb, search_by_key_restarted);
 690                         PROC_INFO_INC(sb,
 691                                       sbk_restarted[expected_level - 1]);
 692                         pathrelse(search_path);
 693
 694                         /* Get the root block number so that we can repeat the search
 695                            starting from the root. */
 696                         block_number = SB_ROOT_BLOCK(sb);
 697                         expected_level = -1;
 698                         right_neighbor_of_leaf_node = 0;
 699
 700                         /* repeat search from the root */
 701                         continue;
 702                 }
 703
 704                 /* only check that the key is in the buffer if key is not
 705                    equal to the MAX_KEY. Latter case is only possible in
 706                    "finish_unfinished()" processing during mount. */
 707                 RFALSE(comp_keys(&MAX_KEY, key) &&
 708                        !key_in_buffer(search_path, key, sb),
 709                        "PAP-5130: key is not in the buffer");
 710 #ifdef CONFIG_REISERFS_CHECK
 711                 if (REISERFS_SB(sb)->cur_tb) {
 712                         print_cur_tb("5140");
 713                         reiserfs_panic(sb, "PAP-5140",
 714                                        "schedule occurred in do_balance!");
 715                 }
 716 #endif
 717
 718                 // make sure, that the node contents look like a node of
 719                 // certain level
 720                 if (!is_tree_node(bh, expected_level)) {
 721                         reiserfs_error(sb, "vs-5150",
 722                                        "invalid format found in block %ld. "
 723                                        "Fsck?", bh->b_blocknr);
 724                         pathrelse(search_path);
 725                         return IO_ERROR;
 726                 }
 727
 728                 /* ok, we have acquired next formatted node in the tree */
 729                 node_level = B_LEVEL(bh);
 730
 731                 PROC_INFO_BH_STAT(sb, bh, node_level - 1);
 732
 733                 RFALSE(node_level < stop_level,
 734                        "vs-5152: tree level (%d) is less than stop level (%d)",
 735                        node_level, stop_level);
 736
 737                 retval = bin_search(key, B_N_PITEM_HEAD(bh, 0),
 738                                       B_NR_ITEMS(bh),
 739                                       (node_level ==
 740                                        DISK_LEAF_NODE_LEVEL) ? IH_SIZE :
 741                                       KEY_SIZE,
 742                                       &(last_element->pe_position));
 743                 if (node_level == stop_level) {
 744                         return retval;
 745                 }
 746
 747                 /* we are not in the stop level */
 748                 if (retval == ITEM_FOUND)
 749                         /* item has been found, so we choose the pointer which is to the right of the found one */
 750                         last_element->pe_position++;
 751
 752                 /* if item was not found we choose the position which is to
 753                    the left of the found item. This requires no code,
 754                    bin_search did it already. */
 755
 756                 /* So we have chosen a position in the current node which is
 757                    an internal node.  Now we calculate child block number by
 758                    position in the node. */
 759                 block_number =
 760                     B_N_CHILD_NUM(bh, last_element->pe_position);
 761
 762                 /* if we are going to read leaf nodes, try for read ahead as well */
 763                 if ((search_path->reada & PATH_READA) &&
 764                     node_level == DISK_LEAF_NODE_LEVEL + 1) {
 765                         int pos = last_element->pe_position;
 766                         int limit = B_NR_ITEMS(bh);
 767                         struct reiserfs_key *le_key;
 768
 769                         if (search_path->reada & PATH_READA_BACK)
 770                                 limit = 0;
 771                         while (reada_count < SEARCH_BY_KEY_READA) {
 772                                 if (pos == limit)
 773                                         break;
 774                                 reada_blocks[reada_count++] =
 775                                     B_N_CHILD_NUM(bh, pos);
 776                                 if (search_path->reada & PATH_READA_BACK)
 777                                         pos--;
 778                                 else
 779                                         pos++;
 780
 781                                 /*
 782                                  * check to make sure we're in the same object
 783                                  */
 784                                 le_key = B_N_PDELIM_KEY(bh, pos);
 785                                 if (le32_to_cpu(le_key->k_objectid) !=
 786                                     key->on_disk_key.k_objectid) {
 787                                         break;
 788                                 }
 789                         }
 790                 }
 791         }
 792 }
 793
 794 /* Form the path to an item and position in this item which contains
 795    file byte defined by key. If there is no such item
 796    corresponding to the key, we point the path to the item with
 797    maximal key less than key, and *pos_in_item is set to one
 798    past the last entry/byte in the item.  If searching for entry in a
 799    directory item, and it is not found, *pos_in_item is set to one
 800    entry more than the entry with maximal key which is less than the
 801    sought key.
 802
 803    Note that if there is no entry in this same node which is one more,
 804    then we point to an imaginary entry.  for direct items, the
 805    position is in units of bytes, for indirect items the position is
 806    in units of blocknr entries, for directory items the position is in
 807    units of directory entries.  */
 808
 809 /* The function is NOT SCHEDULE-SAFE! */
 810 int search_for_position_by_key(struct super_block *sb,  /* Pointer to the super block.          */
 811                                const struct cpu_key *p_cpu_key, /* Key to search (cpu variable)         */
 812                                struct treepath *search_path     /* Filled up by this function.          */
 813     )
 814 {
 815         struct item_head *p_le_ih;      /* pointer to on-disk structure */
 816         int blk_size;
 817         loff_t item_offset, offset;
 818         struct reiserfs_dir_entry de;
 819         int retval;
 820
 821         /* If searching for directory entry. */
 822         if (is_direntry_cpu_key(p_cpu_key))
 823                 return search_by_entry_key(sb, p_cpu_key, search_path,
 824                                            &de);
 825
 826         /* If not searching for directory entry. */
 827
 828         /* If item is found. */
 829         retval = search_item(sb, p_cpu_key, search_path);
 830         if (retval == IO_ERROR)
 831                 return retval;
 832         if (retval == ITEM_FOUND) {
 833
 834                 RFALSE(!ih_item_len
 835                        (B_N_PITEM_HEAD
 836                         (PATH_PLAST_BUFFER(search_path),
 837                          PATH_LAST_POSITION(search_path))),
 838                        "PAP-5165: item length equals zero");
 839
 840                 pos_in_item(search_path) = 0;
 841                 return POSITION_FOUND;
 842         }
 843
 844         RFALSE(!PATH_LAST_POSITION(search_path),
 845                "PAP-5170: position equals zero");
 846
 847         /* Item is not found. Set path to the previous item. */
 848         p_le_ih =
 849             B_N_PITEM_HEAD(PATH_PLAST_BUFFER(search_path),
 850                            --PATH_LAST_POSITION(search_path));
 851         blk_size = sb->s_blocksize;
 852
 853         if (comp_short_keys(&(p_le_ih->ih_key), p_cpu_key)) {
 854                 return FILE_NOT_FOUND;
 855         }
 856         // FIXME: quite ugly this far
 857
 858         item_offset = le_ih_k_offset(p_le_ih);
 859         offset = cpu_key_k_offset(p_cpu_key);
 860
 861         /* Needed byte is contained in the item pointed to by the path. */
 862         if (item_offset <= offset &&
 863             item_offset + op_bytes_number(p_le_ih, blk_size) > offset) {
 864                 pos_in_item(search_path) = offset - item_offset;
 865                 if (is_indirect_le_ih(p_le_ih)) {
 866                         pos_in_item(search_path) /= blk_size;
 867                 }
 868                 return POSITION_FOUND;
 869         }
 870
 871         /* Needed byte is not contained in the item pointed to by the
 872            path. Set pos_in_item out of the item. */
 873         if (is_indirect_le_ih(p_le_ih))
 874                 pos_in_item(search_path) =
 875                     ih_item_len(p_le_ih) / UNFM_P_SIZE;
 876         else
 877                 pos_in_item(search_path) = ih_item_len(p_le_ih);
 878
 879         return POSITION_NOT_FOUND;
 880 }
 881
 882 /* Compare given item and item pointed to by the path. */
 883 int comp_items(const struct item_head *stored_ih, const struct treepath *path)
 884 {
 885         struct buffer_head *bh = PATH_PLAST_BUFFER(path);
 886         struct item_head *ih;
 887
 888         /* Last buffer at the path is not in the tree. */
 889         if (!B_IS_IN_TREE(bh))
 890                 return 1;
 891
 892         /* Last path position is invalid. */
 893         if (PATH_LAST_POSITION(path) >= B_NR_ITEMS(bh))
 894                 return 1;
 895
 896         /* we need only to know, whether it is the same item */
 897         ih = get_ih(path);
 898         return memcmp(stored_ih, ih, IH_SIZE);
 899 }
 900
 901 /* unformatted nodes are not logged anymore, ever.  This is safe
 902 ** now
 903 */
 904 #define held_by_others(bh) (atomic_read(&(bh)->b_count) > 1)
 905
 906 // block can not be forgotten as it is in I/O or held by someone
 907 #define block_in_use(bh) (buffer_locked(bh) || (held_by_others(bh)))
 908
 909 // prepare for delete or cut of direct item
 910 static inline int prepare_for_direct_item(struct treepath *path,
 911                                           struct item_head *le_ih,
 912                                           struct inode *inode,
 913                                           loff_t new_file_length, int *cut_size)
 914 {
 915         loff_t round_len;
 916
 917         if (new_file_length == max_reiserfs_offset(inode)) {
 918                 /* item has to be deleted */
 919                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 920                 return M_DELETE;
 921         }
 922         // new file gets truncated
 923         if (get_inode_item_key_version(inode) == KEY_FORMAT_3_6) {
 924                 //
 925                 round_len = ROUND_UP(new_file_length);
 926                 /* this was new_file_length < le_ih ... */
 927                 if (round_len < le_ih_k_offset(le_ih)) {
 928                         *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 929                         return M_DELETE;        /* Delete this item. */
 930                 }
 931                 /* Calculate first position and size for cutting from item. */
 932                 pos_in_item(path) = round_len - (le_ih_k_offset(le_ih) - 1);
 933                 *cut_size = -(ih_item_len(le_ih) - pos_in_item(path));
 934
 935                 return M_CUT;   /* Cut from this item. */
 936         }
 937
 938         // old file: items may have any length
 939
 940         if (new_file_length < le_ih_k_offset(le_ih)) {
 941                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 942                 return M_DELETE;        /* Delete this item. */
 943         }
 944         /* Calculate first position and size for cutting from item. */
 945         *cut_size = -(ih_item_len(le_ih) -
 946                       (pos_in_item(path) =
 947                        new_file_length + 1 - le_ih_k_offset(le_ih)));
 948         return M_CUT;           /* Cut from this item. */
 949 }
 950
 951 static inline int prepare_for_direntry_item(struct treepath *path,
 952                                             struct item_head *le_ih,
 953                                             struct inode *inode,
 954                                             loff_t new_file_length,
 955                                             int *cut_size)
 956 {
 957         if (le_ih_k_offset(le_ih) == DOT_OFFSET &&
 958             new_file_length == max_reiserfs_offset(inode)) {
 959                 RFALSE(ih_entry_count(le_ih) != 2,
 960                        "PAP-5220: incorrect empty directory item (%h)", le_ih);
 961                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 962                 return M_DELETE;        /* Delete the directory item containing "." and ".." entry. */
 963         }
 964
 965         if (ih_entry_count(le_ih) == 1) {
 966                 /* Delete the directory item such as there is one record only
 967                    in this item */
 968                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 969                 return M_DELETE;
 970         }
 971
 972         /* Cut one record from the directory item. */
 973         *cut_size =
 974             -(DEH_SIZE +
 975               entry_length(get_last_bh(path), le_ih, pos_in_item(path)));
 976         return M_CUT;
 977 }
 978
 979 #define JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD (2 * JOURNAL_PER_BALANCE_CNT + 1)
 980
 981 /*  If the path points to a directory or direct item, calculate mode and the size cut, for balance.
 982     If the path points to an indirect item, remove some number of its unformatted nodes.
 983     In case of file truncate calculate whether this item must be deleted/truncated or last
 984     unformatted node of this item will be converted to a direct item.
 985     This function returns a determination of what balance mode the calling function should employ. */
 986 static char prepare_for_delete_or_cut(struct reiserfs_transaction_handle *th, struct inode *inode, struct treepath *path, const struct cpu_key *item_key, int *removed, /* Number of unformatted nodes which were removed
 987                                                                                                                                                                                    from end of the file. */
 988                                       int *cut_size, unsigned long long new_file_length /* MAX_KEY_OFFSET in case of delete. */
 989     )
 990 {
 991         struct super_block *sb = inode->i_sb;
 992         struct item_head *p_le_ih = PATH_PITEM_HEAD(path);
 993         struct buffer_head *bh = PATH_PLAST_BUFFER(path);
 994
 995         BUG_ON(!th->t_trans_id);
 996
 997         /* Stat_data item. */
 998         if (is_statdata_le_ih(p_le_ih)) {
 999
1000                 RFALSE(new_file_length != max_reiserfs_offset(inode),
1001                        "PAP-5210: mode must be M_DELETE");
1002
1003                 *cut_size = -(IH_SIZE + ih_item_len(p_le_ih));
1004                 return M_DELETE;
1005         }
1006
1007         /* Directory item. */
1008         if (is_direntry_le_ih(p_le_ih))
1009                 return prepare_for_direntry_item(path, p_le_ih, inode,
1010                                                  new_file_length,
1011                                                  cut_size);
1012
1013         /* Direct item. */
1014         if (is_direct_le_ih(p_le_ih))
1015                 return prepare_for_direct_item(path, p_le_ih, inode,
1016                                                new_file_length, cut_size);
1017
1018         /* Case of an indirect item. */
1019         {
1020             int blk_size = sb->s_blocksize;
1021             struct item_head s_ih;
1022             int need_re_search;
1023             int delete = 0;
1024             int result = M_CUT;
1025             int pos = 0;
1026
1027             if ( new_file_length == max_reiserfs_offset (inode) ) {
1028                 /* prepare_for_delete_or_cut() is called by
1029                  * reiserfs_delete_item() */
1030                 new_file_length = 0;
1031                 delete = 1;
1032             }
1033
1034             do {
1035                 need_re_search = 0;
1036                 *cut_size = 0;
1037                 bh = PATH_PLAST_BUFFER(path);
1038                 copy_item_head(&s_ih, PATH_PITEM_HEAD(path));
1039                 pos = I_UNFM_NUM(&s_ih);
1040
1041                 while (le_ih_k_offset (&s_ih) + (pos - 1) * blk_size > new_file_length) {
1042                     __le32 *unfm;
1043                     __u32 block;
1044
1045                     /* Each unformatted block deletion may involve one additional
1046                      * bitmap block into the transaction, thereby the initial
1047                      * journal space reservation might not be enough. */
1048                     if (!delete && (*cut_size) != 0 &&
1049                         reiserfs_transaction_free_space(th) < JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD)
1050                         break;
1051
1052                     unfm = (__le32 *)B_I_PITEM(bh, &s_ih) + pos - 1;
1053                     block = get_block_num(unfm, 0);
1054
1055                     if (block != 0) {
1056                         reiserfs_prepare_for_journal(sb, bh, 1);
1057                         put_block_num(unfm, 0, 0);
1058                         journal_mark_dirty(th, sb, bh);
1059                         reiserfs_free_block(th, inode, block, 1);
1060                     }
1061
1062                     reiserfs_write_unlock(sb);
1063                     cond_resched();
1064                     reiserfs_write_lock(sb);
1065
1066                     if (item_moved (&s_ih, path))  {
1067                         need_re_search = 1;
1068                         break;
1069                     }
1070
1071                     pos --;
1072                     (*removed)++;
1073                     (*cut_size) -= UNFM_P_SIZE;
1074
1075                     if (pos == 0) {
1076                         (*cut_size) -= IH_SIZE;
1077                         result = M_DELETE;
1078                         break;
1079                     }
1080                 }
1081                 /* a trick.  If the buffer has been logged, this will do nothing.  If
1082                 ** we've broken the loop without logging it, it will restore the
1083                 ** buffer */
1084                 reiserfs_restore_prepared_buffer(sb, bh);
1085             } while (need_re_search &&
1086                      search_for_position_by_key(sb, item_key, path) == POSITION_FOUND);
1087             pos_in_item(path) = pos * UNFM_P_SIZE;
1088
1089             if (*cut_size == 0) {
1090                 /* Nothing were cut. maybe convert last unformatted node to the
1091                  * direct item? */
1092                 result = M_CONVERT;
1093             }
1094             return result;
1095         }
1096 }
1097
1098 /* Calculate number of bytes which will be deleted or cut during balance */
1099 static int calc_deleted_bytes_number(struct tree_balance *tb, char mode)
1100 {
1101         int del_size;
1102         struct item_head *p_le_ih = PATH_PITEM_HEAD(tb->tb_path);
1103
1104         if (is_statdata_le_ih(p_le_ih))
1105                 return 0;
1106
1107         del_size =
1108             (mode ==
1109              M_DELETE) ? ih_item_len(p_le_ih) : -tb->insert_size[0];
1110         if (is_direntry_le_ih(p_le_ih)) {
1111                 /* return EMPTY_DIR_SIZE; We delete emty directoris only.
1112                  * we can't use EMPTY_DIR_SIZE, as old format dirs have a different
1113                  * empty size.  ick. FIXME, is this right? */
1114                 return del_size;
1115         }
1116
1117         if (is_indirect_le_ih(p_le_ih))
1118                 del_size = (del_size / UNFM_P_SIZE) *
1119                                 (PATH_PLAST_BUFFER(tb->tb_path)->b_size);
1120         return del_size;
1121 }
1122
1123 static void init_tb_struct(struct reiserfs_transaction_handle *th,
1124                            struct tree_balance *tb,
1125                            struct super_block *sb,
1126                            struct treepath *path, int size)
1127 {
1128
1129         BUG_ON(!th->t_trans_id);
1130
1131         memset(tb, '\0', sizeof(struct tree_balance));
1132         tb->transaction_handle = th;
1133         tb->tb_sb = sb;
1134         tb->tb_path = path;
1135         PATH_OFFSET_PBUFFER(path, ILLEGAL_PATH_ELEMENT_OFFSET) = NULL;
1136         PATH_OFFSET_POSITION(path, ILLEGAL_PATH_ELEMENT_OFFSET) = 0;
1137         tb->insert_size[0] = size;
1138 }
1139
1140 void padd_item(char *item, int total_length, int length)
1141 {
1142         int i;
1143
1144         for (i = total_length; i > length;)
1145                 item[--i] = 0;
1146 }
1147
1148 #ifdef REISERQUOTA_DEBUG
1149 char key2type(struct reiserfs_key *ih)
1150 {
1151         if (is_direntry_le_key(2, ih))
1152                 return 'd';
1153         if (is_direct_le_key(2, ih))
1154                 return 'D';
1155         if (is_indirect_le_key(2, ih))
1156                 return 'i';
1157         if (is_statdata_le_key(2, ih))
1158                 return 's';
1159         return 'u';
1160 }
1161
1162 char head2type(struct item_head *ih)
1163 {
1164         if (is_direntry_le_ih(ih))
1165                 return 'd';
1166         if (is_direct_le_ih(ih))
1167                 return 'D';
1168         if (is_indirect_le_ih(ih))
1169                 return 'i';
1170         if (is_statdata_le_ih(ih))
1171                 return 's';
1172         return 'u';
1173 }
1174 #endif
1175
1176 /* Delete object item.
1177  * th       - active transaction handle
1178  * path     - path to the deleted item
1179  * item_key - key to search for the deleted item
1180  * indode   - used for updating i_blocks and quotas
1181  * un_bh    - NULL or unformatted node pointer
1182  */
1183 int reiserfs_delete_item(struct reiserfs_transaction_handle *th,
1184                          struct treepath *path, const struct cpu_key *item_key,
1185                          struct inode *inode, struct buffer_head *un_bh)
1186 {
1187         struct super_block *sb = inode->i_sb;
1188         struct tree_balance s_del_balance;
1189         struct item_head s_ih;
1190         struct item_head *q_ih;
1191         int quota_cut_bytes;
1192         int ret_value, del_size, removed;
1193
1194 #ifdef CONFIG_REISERFS_CHECK
1195         char mode;
1196         int iter = 0;
1197 #endif
1198
1199         BUG_ON(!th->t_trans_id);
1200
1201         init_tb_struct(th, &s_del_balance, sb, path,
1202                        0 /*size is unknown */ );
1203
1204         while (1) {
1205                 removed = 0;
1206
1207 #ifdef CONFIG_REISERFS_CHECK
1208                 iter++;
1209                 mode =
1210 #endif
1211                     prepare_for_delete_or_cut(th, inode, path,
1212                                               item_key, &removed,
1213                                               &del_size,
1214                                               max_reiserfs_offset(inode));
1215
1216                 RFALSE(mode != M_DELETE, "PAP-5320: mode must be M_DELETE");
1217
1218                 copy_item_head(&s_ih, PATH_PITEM_HEAD(path));
1219                 s_del_balance.insert_size[0] = del_size;
1220
1221                 ret_value = fix_nodes(M_DELETE, &s_del_balance, NULL, NULL);
1222                 if (ret_value != REPEAT_SEARCH)
1223                         break;
1224
1225                 PROC_INFO_INC(sb, delete_item_restarted);
1226
1227                 // file system changed, repeat search
1228                 ret_value =
1229                     search_for_position_by_key(sb, item_key, path);
1230                 if (ret_value == IO_ERROR)
1231                         break;
1232                 if (ret_value == FILE_NOT_FOUND) {
1233                         reiserfs_warning(sb, "vs-5340",
1234                                          "no items of the file %K found",
1235                                          item_key);
1236                         break;
1237                 }
1238         }                       /* while (1) */
1239
1240         if (ret_value != CARRY_ON) {
1241                 unfix_nodes(&s_del_balance);
1242                 return 0;
1243         }
1244         // reiserfs_delete_item returns item length when success
1245         ret_value = calc_deleted_bytes_number(&s_del_balance, M_DELETE);
1246         q_ih = get_ih(path);
1247         quota_cut_bytes = ih_item_len(q_ih);
1248
1249         /* hack so the quota code doesn't have to guess if the file
1250          ** has a tail.  On tail insert, we allocate quota for 1 unformatted node.
1251          ** We test the offset because the tail might have been
1252          ** split into multiple items, and we only want to decrement for
1253          ** the unfm node once
1254          */
1255         if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(q_ih)) {
1256                 if ((le_ih_k_offset(q_ih) & (sb->s_blocksize - 1)) == 1) {
1257                         quota_cut_bytes = sb->s_blocksize + UNFM_P_SIZE;
1258                 } else {
1259                         quota_cut_bytes = 0;
1260                 }
1261         }
1262
1263         if (un_bh) {
1264                 int off;
1265                 char *data;
1266
1267                 /* We are in direct2indirect conversion, so move tail contents
1268                    to the unformatted node */
1269                 /* note, we do the copy before preparing the buffer because we
1270                  ** don't care about the contents of the unformatted node yet.
1271                  ** the only thing we really care about is the direct item's data
1272                  ** is in the unformatted node.
1273                  **
1274                  ** Otherwise, we would have to call reiserfs_prepare_for_journal on
1275                  ** the unformatted node, which might schedule, meaning we'd have to
1276                  ** loop all the way back up to the start of the while loop.
1277                  **
1278                  ** The unformatted node must be dirtied later on.  We can't be
1279                  ** sure here if the entire tail has been deleted yet.
1280                  **
1281                  ** un_bh is from the page cache (all unformatted nodes are
1282                  ** from the page cache) and might be a highmem page.  So, we
1283                  ** can't use un_bh->b_data.
1284                  ** -clm
1285                  */
1286
1287                 data = kmap_atomic(un_bh->b_page);
1288                 off = ((le_ih_k_offset(&s_ih) - 1) & (PAGE_CACHE_SIZE - 1));
1289                 memcpy(data + off,
1290                        B_I_PITEM(PATH_PLAST_BUFFER(path), &s_ih),
1291                        ret_value);
1292                 kunmap_atomic(data);
1293         }
1294         /* Perform balancing after all resources have been collected at once. */
1295         do_balance(&s_del_balance, NULL, NULL, M_DELETE);
1296
1297 #ifdef REISERQUOTA_DEBUG
1298         reiserfs_debug(sb, REISERFS_DEBUG_CODE,
1299                        "reiserquota delete_item(): freeing %u, id=%u type=%c",
1300                        quota_cut_bytes, inode->i_uid, head2type(&s_ih));
1301 #endif
1302         dquot_free_space_nodirty(inode, quota_cut_bytes);
1303
1304         /* Return deleted body length */
1305         return ret_value;
1306 }
1307
1308 /* Summary Of Mechanisms For Handling Collisions Between Processes:
1309
1310  deletion of the body of the object is performed by iput(), with the
1311  result that if multiple processes are operating on a file, the
1312  deletion of the body of the file is deferred until the last process
1313  that has an open inode performs its iput().
1314
1315  writes and truncates are protected from collisions by use of
1316  semaphores.
1317
1318  creates, linking, and mknod are protected from collisions with other
1319  processes by making the reiserfs_add_entry() the last step in the
1320  creation, and then rolling back all changes if there was a collision.
1321  - Hans
1322 */
1323
1324 /* this deletes item which never gets split */
1325 void reiserfs_delete_solid_item(struct reiserfs_transaction_handle *th,
1326                                 struct inode *inode, struct reiserfs_key *key)
1327 {
1328         struct tree_balance tb;
1329         INITIALIZE_PATH(path);
1330         int item_len = 0;
1331         int tb_init = 0;
1332         struct cpu_key cpu_key;
1333         int retval;
1334         int quota_cut_bytes = 0;
1335
1336         BUG_ON(!th->t_trans_id);
1337
1338         le_key2cpu_key(&cpu_key, key);
1339
1340         while (1) {
1341                 retval = search_item(th->t_super, &cpu_key, &path);
1342                 if (retval == IO_ERROR) {
1343                         reiserfs_error(th->t_super, "vs-5350",
1344                                        "i/o failure occurred trying "
1345                                        "to delete %K", &cpu_key);
1346                         break;
1347                 }
1348                 if (retval != ITEM_FOUND) {
1349                         pathrelse(&path);
1350                         // No need for a warning, if there is just no free space to insert '..' item into the newly-created subdir
1351                         if (!
1352                             ((unsigned long long)
1353                              GET_HASH_VALUE(le_key_k_offset
1354                                             (le_key_version(key), key)) == 0
1355                              && (unsigned long long)
1356                              GET_GENERATION_NUMBER(le_key_k_offset
1357                                                    (le_key_version(key),
1358                                                     key)) == 1))
1359                                 reiserfs_warning(th->t_super, "vs-5355",
1360                                                  "%k not found", key);
1361                         break;
1362                 }
1363                 if (!tb_init) {
1364                         tb_init = 1;
1365                         item_len = ih_item_len(PATH_PITEM_HEAD(&path));
1366                         init_tb_struct(th, &tb, th->t_super, &path,
1367                                        -(IH_SIZE + item_len));
1368                 }
1369                 quota_cut_bytes = ih_item_len(PATH_PITEM_HEAD(&path));
1370
1371                 retval = fix_nodes(M_DELETE, &tb, NULL, NULL);
1372                 if (retval == REPEAT_SEARCH) {
1373                         PROC_INFO_INC(th->t_super, delete_solid_item_restarted);
1374                         continue;
1375                 }
1376
1377                 if (retval == CARRY_ON) {
1378                         do_balance(&tb, NULL, NULL, M_DELETE);
1379                         if (inode) {    /* Should we count quota for item? (we don't count quotas for save-links) */
1380 #ifdef REISERQUOTA_DEBUG
1381                                 reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
1382                                                "reiserquota delete_solid_item(): freeing %u id=%u type=%c",
1383                                                quota_cut_bytes, inode->i_uid,
1384                                                key2type(key));
1385 #endif
1386                                 dquot_free_space_nodirty(inode,
1387                                                          quota_cut_bytes);
1388                         }
1389                         break;
1390                 }
1391                 // IO_ERROR, NO_DISK_SPACE, etc
1392                 reiserfs_warning(th->t_super, "vs-5360",
1393                                  "could not delete %K due to fix_nodes failure",
1394                                  &cpu_key);
1395                 unfix_nodes(&tb);
1396                 break;
1397         }
1398
1399         reiserfs_check_path(&path);
1400 }
1401
1402 int reiserfs_delete_object(struct reiserfs_transaction_handle *th,
1403                            struct inode *inode)
1404 {
1405         int err;
1406         inode->i_size = 0;
1407         BUG_ON(!th->t_trans_id);
1408
1409         /* for directory this deletes item containing "." and ".." */
1410         err =
1411             reiserfs_do_truncate(th, inode, NULL, 0 /*no timestamp updates */ );
1412         if (err)
1413                 return err;
1414
1415 #if defined( USE_INODE_GENERATION_COUNTER )
1416         if (!old_format_only(th->t_super)) {
1417                 __le32 *inode_generation;
1418
1419                 inode_generation =
1420                     &REISERFS_SB(th->t_super)->s_rs->s_inode_generation;
1421                 le32_add_cpu(inode_generation, 1);
1422         }
1423 /* USE_INODE_GENERATION_COUNTER */
1424 #endif
1425         reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode));
1426
1427         return err;
1428 }
1429
1430 static void unmap_buffers(struct page *page, loff_t pos)
1431 {
1432         struct buffer_head *bh;
1433         struct buffer_head *head;
1434         struct buffer_head *next;
1435         unsigned long tail_index;
1436         unsigned long cur_index;
1437
1438         if (page) {
1439                 if (page_has_buffers(page)) {
1440                         tail_index = pos & (PAGE_CACHE_SIZE - 1);
1441                         cur_index = 0;
1442                         head = page_buffers(page);
1443                         bh = head;
1444                         do {
1445                                 next = bh->b_this_page;
1446
1447                                 /* we want to unmap the buffers that contain the tail, and
1448                                  ** all the buffers after it (since the tail must be at the
1449                                  ** end of the file).  We don't want to unmap file data
1450                                  ** before the tail, since it might be dirty and waiting to
1451                                  ** reach disk
1452                                  */
1453                                 cur_index += bh->b_size;
1454                                 if (cur_index > tail_index) {
1455                                         reiserfs_unmap_buffer(bh);
1456                                 }
1457                                 bh = next;
1458                         } while (bh != head);
1459                 }
1460         }
1461 }
1462
1463 static int maybe_indirect_to_direct(struct reiserfs_transaction_handle *th,
1464                                     struct inode *inode,
1465                                     struct page *page,
1466                                     struct treepath *path,
1467                                     const struct cpu_key *item_key,
1468                                     loff_t new_file_size, char *mode)
1469 {
1470         struct super_block *sb = inode->i_sb;
1471         int block_size = sb->s_blocksize;
1472         int cut_bytes;
1473         BUG_ON(!th->t_trans_id);
1474         BUG_ON(new_file_size != inode->i_size);
1475
1476         /* the page being sent in could be NULL if there was an i/o error
1477          ** reading in the last block.  The user will hit problems trying to
1478          ** read the file, but for now we just skip the indirect2direct
1479          */
1480         if (atomic_read(&inode->i_count) > 1 ||
1481             !tail_has_to_be_packed(inode) ||
1482             !page || (REISERFS_I(inode)->i_flags & i_nopack_mask)) {
1483                 /* leave tail in an unformatted node */
1484                 *mode = M_SKIP_BALANCING;
1485                 cut_bytes =
1486                     block_size - (new_file_size & (block_size - 1));
1487                 pathrelse(path);
1488                 return cut_bytes;
1489         }
1490         /* Perform the conversion to a direct_item. */
1491         /* return indirect_to_direct(inode, path, item_key,
1492                                   new_file_size, mode); */
1493         return indirect2direct(th, inode, page, path, item_key,
1494                                new_file_size, mode);
1495 }
1496
1497 /* we did indirect_to_direct conversion. And we have inserted direct
1498    item successesfully, but there were no disk space to cut unfm
1499    pointer being converted. Therefore we have to delete inserted
1500    direct item(s) */
1501 static void indirect_to_direct_roll_back(struct reiserfs_transaction_handle *th,
1502                                          struct inode *inode, struct treepath *path)
1503 {
1504         struct cpu_key tail_key;
1505         int tail_len;
1506         int removed;
1507         BUG_ON(!th->t_trans_id);
1508
1509         make_cpu_key(&tail_key, inode, inode->i_size + 1, TYPE_DIRECT, 4);      // !!!!
1510         tail_key.key_length = 4;
1511
1512         tail_len =
1513             (cpu_key_k_offset(&tail_key) & (inode->i_sb->s_blocksize - 1)) - 1;
1514         while (tail_len) {
1515                 /* look for the last byte of the tail */
1516                 if (search_for_position_by_key(inode->i_sb, &tail_key, path) ==
1517                     POSITION_NOT_FOUND)
1518                         reiserfs_panic(inode->i_sb, "vs-5615",
1519                                        "found invalid item");
1520                 RFALSE(path->pos_in_item !=
1521                        ih_item_len(PATH_PITEM_HEAD(path)) - 1,
1522                        "vs-5616: appended bytes found");
1523                 PATH_LAST_POSITION(path)--;
1524
1525                 removed =
1526                     reiserfs_delete_item(th, path, &tail_key, inode,
1527                                          NULL /*unbh not needed */ );
1528                 RFALSE(removed <= 0
1529                        || removed > tail_len,
1530                        "vs-5617: there was tail %d bytes, removed item length %d bytes",
1531                        tail_len, removed);
1532                 tail_len -= removed;
1533                 set_cpu_key_k_offset(&tail_key,
1534                                      cpu_key_k_offset(&tail_key) - removed);
1535         }
1536         reiserfs_warning(inode->i_sb, "reiserfs-5091", "indirect_to_direct "
1537                          "conversion has been rolled back due to "
1538                          "lack of disk space");
1539         //mark_file_without_tail (inode);
1540         mark_inode_dirty(inode);
1541 }
1542
1543 /* (Truncate or cut entry) or delete object item. Returns < 0 on failure */
1544 int reiserfs_cut_from_item(struct reiserfs_transaction_handle *th,
1545                            struct treepath *path,
1546                            struct cpu_key *item_key,
1547                            struct inode *inode,
1548                            struct page *page, loff_t new_file_size)
1549 {
1550         struct super_block *sb = inode->i_sb;
1551         /* Every function which is going to call do_balance must first
1552            create a tree_balance structure.  Then it must fill up this
1553            structure by using the init_tb_struct and fix_nodes functions.
1554            After that we can make tree balancing. */
1555         struct tree_balance s_cut_balance;
1556         struct item_head *p_le_ih;
1557         int cut_size = 0,       /* Amount to be cut. */
1558             ret_value = CARRY_ON, removed = 0,  /* Number of the removed unformatted nodes. */
1559             is_inode_locked = 0;
1560         char mode;              /* Mode of the balance. */
1561         int retval2 = -1;
1562         int quota_cut_bytes;
1563         loff_t tail_pos = 0;
1564
1565         BUG_ON(!th->t_trans_id);
1566
1567         init_tb_struct(th, &s_cut_balance, inode->i_sb, path,
1568                        cut_size);
1569
1570         /* Repeat this loop until we either cut the item without needing
1571            to balance, or we fix_nodes without schedule occurring */
1572         while (1) {
1573                 /* Determine the balance mode, position of the first byte to
1574                    be cut, and size to be cut.  In case of the indirect item
1575                    free unformatted nodes which are pointed to by the cut
1576                    pointers. */
1577
1578                 mode =
1579                     prepare_for_delete_or_cut(th, inode, path,
1580                                               item_key, &removed,
1581                                               &cut_size, new_file_size);
1582                 if (mode == M_CONVERT) {
1583                         /* convert last unformatted node to direct item or leave
1584                            tail in the unformatted node */
1585                         RFALSE(ret_value != CARRY_ON,
1586                                "PAP-5570: can not convert twice");
1587
1588                         ret_value =
1589                             maybe_indirect_to_direct(th, inode, page,
1590                                                      path, item_key,
1591                                                      new_file_size, &mode);
1592                         if (mode == M_SKIP_BALANCING)
1593                                 /* tail has been left in the unformatted node */
1594                                 return ret_value;
1595
1596                         is_inode_locked = 1;
1597
1598                         /* removing of last unformatted node will change value we
1599                            have to return to truncate. Save it */
1600                         retval2 = ret_value;
1601                         /*retval2 = sb->s_blocksize - (new_file_size & (sb->s_blocksize - 1)); */
1602
1603                         /* So, we have performed the first part of the conversion:
1604                            inserting the new direct item.  Now we are removing the
1605                            last unformatted node pointer. Set key to search for
1606                            it. */
1607                         set_cpu_key_k_type(item_key, TYPE_INDIRECT);
1608                         item_key->key_length = 4;
1609                         new_file_size -=
1610                             (new_file_size & (sb->s_blocksize - 1));
1611                         tail_pos = new_file_size;
1612                         set_cpu_key_k_offset(item_key, new_file_size + 1);
1613                         if (search_for_position_by_key
1614                             (sb, item_key,
1615                              path) == POSITION_NOT_FOUND) {
1616                                 print_block(PATH_PLAST_BUFFER(path), 3,
1617                                             PATH_LAST_POSITION(path) - 1,
1618                                             PATH_LAST_POSITION(path) + 1);
1619                                 reiserfs_panic(sb, "PAP-5580", "item to "
1620                                                "convert does not exist (%K)",
1621                                                item_key);
1622                         }
1623                         continue;
1624                 }
1625                 if (cut_size == 0) {
1626                         pathrelse(path);
1627                         return 0;
1628                 }
1629
1630                 s_cut_balance.insert_size[0] = cut_size;
1631
1632                 ret_value = fix_nodes(mode, &s_cut_balance, NULL, NULL);
1633                 if (ret_value != REPEAT_SEARCH)
1634                         break;
1635
1636                 PROC_INFO_INC(sb, cut_from_item_restarted);
1637
1638                 ret_value =
1639                     search_for_position_by_key(sb, item_key, path);
1640                 if (ret_value == POSITION_FOUND)
1641                         continue;
1642
1643                 reiserfs_warning(sb, "PAP-5610", "item %K not found",
1644                                  item_key);
1645                 unfix_nodes(&s_cut_balance);
1646                 return (ret_value == IO_ERROR) ? -EIO : -ENOENT;
1647         }                       /* while */
1648
1649         // check fix_nodes results (IO_ERROR or NO_DISK_SPACE)
1650         if (ret_value != CARRY_ON) {
1651                 if (is_inode_locked) {
1652                         // FIXME: this seems to be not needed: we are always able
1653                         // to cut item
1654                         indirect_to_direct_roll_back(th, inode, path);
1655                 }
1656                 if (ret_value == NO_DISK_SPACE)
1657                         reiserfs_warning(sb, "reiserfs-5092",
1658                                          "NO_DISK_SPACE");
1659                 unfix_nodes(&s_cut_balance);
1660                 return -EIO;
1661         }
1662
1663         /* go ahead and perform balancing */
1664
1665         RFALSE(mode == M_PASTE || mode == M_INSERT, "invalid mode");
1666
1667         /* Calculate number of bytes that need to be cut from the item. */
1668         quota_cut_bytes =
1669             (mode ==
1670              M_DELETE) ? ih_item_len(get_ih(path)) : -s_cut_balance.
1671             insert_size[0];
1672         if (retval2 == -1)
1673                 ret_value = calc_deleted_bytes_number(&s_cut_balance, mode);
1674         else
1675                 ret_value = retval2;
1676
1677         /* For direct items, we only change the quota when deleting the last
1678          ** item.
1679          */
1680         p_le_ih = PATH_PITEM_HEAD(s_cut_balance.tb_path);
1681         if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(p_le_ih)) {
1682                 if (mode == M_DELETE &&
1683                     (le_ih_k_offset(p_le_ih) & (sb->s_blocksize - 1)) ==
1684                     1) {
1685                         // FIXME: this is to keep 3.5 happy
1686                         REISERFS_I(inode)->i_first_direct_byte = U32_MAX;
1687                         quota_cut_bytes = sb->s_blocksize + UNFM_P_SIZE;
1688                 } else {
1689                         quota_cut_bytes = 0;
1690                 }
1691         }
1692 #ifdef CONFIG_REISERFS_CHECK
1693         if (is_inode_locked) {
1694                 struct item_head *le_ih =
1695                     PATH_PITEM_HEAD(s_cut_balance.tb_path);
1696                 /* we are going to complete indirect2direct conversion. Make
1697                    sure, that we exactly remove last unformatted node pointer
1698                    of the item */
1699                 if (!is_indirect_le_ih(le_ih))
1700                         reiserfs_panic(sb, "vs-5652",
1701                                        "item must be indirect %h", le_ih);
1702
1703                 if (mode == M_DELETE && ih_item_len(le_ih) != UNFM_P_SIZE)
1704                         reiserfs_panic(sb, "vs-5653", "completing "
1705                                        "indirect2direct conversion indirect "
1706                                        "item %h being deleted must be of "
1707                                        "4 byte long", le_ih);
1708
1709                 if (mode == M_CUT
1710                     && s_cut_balance.insert_size[0] != -UNFM_P_SIZE) {
1711                         reiserfs_panic(sb, "vs-5654", "can not complete "
1712                                        "indirect2direct conversion of %h "
1713                                        "(CUT, insert_size==%d)",
1714                                        le_ih, s_cut_balance.insert_size[0]);
1715                 }
1716                 /* it would be useful to make sure, that right neighboring
1717                    item is direct item of this file */
1718         }
1719 #endif
1720
1721         do_balance(&s_cut_balance, NULL, NULL, mode);
1722         if (is_inode_locked) {
1723                 /* we've done an indirect->direct conversion.  when the data block
1724                  ** was freed, it was removed from the list of blocks that must
1725                  ** be flushed before the transaction commits, make sure to
1726                  ** unmap and invalidate it
1727                  */
1728                 unmap_buffers(page, tail_pos);
1729                 REISERFS_I(inode)->i_flags &= ~i_pack_on_close_mask;
1730         }
1731 #ifdef REISERQUOTA_DEBUG
1732         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
1733                        "reiserquota cut_from_item(): freeing %u id=%u type=%c",
1734                        quota_cut_bytes, inode->i_uid, '?');
1735 #endif
1736         dquot_free_space_nodirty(inode, quota_cut_bytes);
1737         return ret_value;
1738 }
1739
1740 static void truncate_directory(struct reiserfs_transaction_handle *th,
1741                                struct inode *inode)
1742 {
1743         BUG_ON(!th->t_trans_id);
1744         if (inode->i_nlink)
1745                 reiserfs_error(inode->i_sb, "vs-5655", "link count != 0");
1746
1747         set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), DOT_OFFSET);
1748         set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_DIRENTRY);
1749         reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode));
1750         reiserfs_update_sd(th, inode);
1751         set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), SD_OFFSET);
1752         set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_STAT_DATA);
1753 }
1754
1755 /* Truncate file to the new size. Note, this must be called with a transaction
1756    already started */
1757 int reiserfs_do_truncate(struct reiserfs_transaction_handle *th,
1758                           struct inode *inode,  /* ->i_size contains new size */
1759                          struct page *page,     /* up to date for last block */
1760                          int update_timestamps  /* when it is called by
1761                                                    file_release to convert
1762                                                    the tail - no timestamps
1763                                                    should be updated */
1764     )
1765 {
1766         INITIALIZE_PATH(s_search_path); /* Path to the current object item. */
1767         struct item_head *p_le_ih;      /* Pointer to an item header. */
1768         struct cpu_key s_item_key;      /* Key to search for a previous file item. */
1769         loff_t file_size,       /* Old file size. */
1770          new_file_size; /* New file size. */
1771         int deleted;            /* Number of deleted or truncated bytes. */
1772         int retval;
1773         int err = 0;
1774
1775         BUG_ON(!th->t_trans_id);
1776         if (!
1777             (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1778              || S_ISLNK(inode->i_mode)))
1779                 return 0;
1780
1781         if (S_ISDIR(inode->i_mode)) {
1782                 // deletion of directory - no need to update timestamps
1783                 truncate_directory(th, inode);
1784                 return 0;
1785         }
1786
1787         /* Get new file size. */
1788         new_file_size = inode->i_size;
1789
1790         // FIXME: note, that key type is unimportant here
1791         make_cpu_key(&s_item_key, inode, max_reiserfs_offset(inode),
1792                      TYPE_DIRECT, 3);
1793
1794         retval =
1795             search_for_position_by_key(inode->i_sb, &s_item_key,
1796                                        &s_search_path);
1797         if (retval == IO_ERROR) {
1798                 reiserfs_error(inode->i_sb, "vs-5657",
1799                                "i/o failure occurred trying to truncate %K",
1800                                &s_item_key);
1801                 err = -EIO;
1802                 goto out;
1803         }
1804         if (retval == POSITION_FOUND || retval == FILE_NOT_FOUND) {
1805                 reiserfs_error(inode->i_sb, "PAP-5660",
1806                                "wrong result %d of search for %K", retval,
1807                                &s_item_key);
1808
1809                 err = -EIO;
1810                 goto out;
1811         }
1812
1813         s_search_path.pos_in_item--;
1814
1815         /* Get real file size (total length of all file items) */
1816         p_le_ih = PATH_PITEM_HEAD(&s_search_path);
1817         if (is_statdata_le_ih(p_le_ih))
1818                 file_size = 0;
1819         else {
1820                 loff_t offset = le_ih_k_offset(p_le_ih);
1821                 int bytes =
1822                     op_bytes_number(p_le_ih, inode->i_sb->s_blocksize);
1823
1824                 /* this may mismatch with real file size: if last direct item
1825                    had no padding zeros and last unformatted node had no free
1826                    space, this file would have this file size */
1827                 file_size = offset + bytes - 1;
1828         }
1829         /*
1830          * are we doing a full truncate or delete, if so
1831          * kick in the reada code
1832          */
1833         if (new_file_size == 0)
1834                 s_search_path.reada = PATH_READA | PATH_READA_BACK;
1835
1836         if (file_size == 0 || file_size < new_file_size) {
1837                 goto update_and_out;
1838         }
1839
1840         /* Update key to search for the last file item. */
1841         set_cpu_key_k_offset(&s_item_key, file_size);
1842
1843         do {
1844                 /* Cut or delete file item. */
1845                 deleted =
1846                     reiserfs_cut_from_item(th, &s_search_path, &s_item_key,
1847                                            inode, page, new_file_size);
1848                 if (deleted < 0) {
1849                         reiserfs_warning(inode->i_sb, "vs-5665",
1850                                          "reiserfs_cut_from_item failed");
1851                         reiserfs_check_path(&s_search_path);
1852                         return 0;
1853                 }
1854
1855                 RFALSE(deleted > file_size,
1856                        "PAP-5670: reiserfs_cut_from_item: too many bytes deleted: deleted %d, file_size %lu, item_key %K",
1857                        deleted, file_size, &s_item_key);
1858
1859                 /* Change key to search the last file item. */
1860                 file_size -= deleted;
1861
1862                 set_cpu_key_k_offset(&s_item_key, file_size);
1863
1864                 /* While there are bytes to truncate and previous file item is presented in the tree. */
1865
1866                 /*
1867                  ** This loop could take a really long time, and could log
1868                  ** many more blocks than a transaction can hold.  So, we do a polite
1869                  ** journal end here, and if the transaction needs ending, we make
1870                  ** sure the file is consistent before ending the current trans
1871                  ** and starting a new one
1872                  */
1873                 if (journal_transaction_should_end(th, 0) ||
1874                     reiserfs_transaction_free_space(th) <= JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD) {
1875                         int orig_len_alloc = th->t_blocks_allocated;
1876                         pathrelse(&s_search_path);
1877
1878                         if (update_timestamps) {
1879                                 inode->i_mtime = CURRENT_TIME_SEC;
1880                                 inode->i_ctime = CURRENT_TIME_SEC;
1881                         }
1882                         reiserfs_update_sd(th, inode);
1883
1884                         err = journal_end(th, inode->i_sb, orig_len_alloc);
1885                         if (err)
1886                                 goto out;
1887                         err = journal_begin(th, inode->i_sb,
1888                                             JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD + JOURNAL_PER_BALANCE_CNT * 4) ;
1889                         if (err)
1890                                 goto out;
1891                         reiserfs_update_inode_transaction(inode);
1892                 }
1893         } while (file_size > ROUND_UP(new_file_size) &&
1894                  search_for_position_by_key(inode->i_sb, &s_item_key,
1895                                             &s_search_path) == POSITION_FOUND);
1896
1897         RFALSE(file_size > ROUND_UP(new_file_size),
1898                "PAP-5680: truncate did not finish: new_file_size %Ld, current %Ld, oid %d",
1899                new_file_size, file_size, s_item_key.on_disk_key.k_objectid);
1900
1901       update_and_out:
1902         if (update_timestamps) {
1903                 // this is truncate, not file closing
1904                 inode->i_mtime = CURRENT_TIME_SEC;
1905                 inode->i_ctime = CURRENT_TIME_SEC;
1906         }
1907         reiserfs_update_sd(th, inode);
1908
1909       out:
1910         pathrelse(&s_search_path);
1911         return err;
1912 }
1913
1914 #ifdef CONFIG_REISERFS_CHECK
1915 // this makes sure, that we __append__, not overwrite or add holes
1916 static void check_research_for_paste(struct treepath *path,
1917                                      const struct cpu_key *key)
1918 {
1919         struct item_head *found_ih = get_ih(path);
1920
1921         if (is_direct_le_ih(found_ih)) {
1922                 if (le_ih_k_offset(found_ih) +
1923                     op_bytes_number(found_ih,
1924                                     get_last_bh(path)->b_size) !=
1925                     cpu_key_k_offset(key)
1926                     || op_bytes_number(found_ih,
1927                                        get_last_bh(path)->b_size) !=
1928                     pos_in_item(path))
1929                         reiserfs_panic(NULL, "PAP-5720", "found direct item "
1930                                        "%h or position (%d) does not match "
1931                                        "to key %K", found_ih,
1932                                        pos_in_item(path), key);
1933         }
1934         if (is_indirect_le_ih(found_ih)) {
1935                 if (le_ih_k_offset(found_ih) +
1936                     op_bytes_number(found_ih,
1937                                     get_last_bh(path)->b_size) !=
1938                     cpu_key_k_offset(key)
1939                     || I_UNFM_NUM(found_ih) != pos_in_item(path)
1940                     || get_ih_free_space(found_ih) != 0)
1941                         reiserfs_panic(NULL, "PAP-5730", "found indirect "
1942                                        "item (%h) or position (%d) does not "
1943                                        "match to key (%K)",
1944                                        found_ih, pos_in_item(path), key);
1945         }
1946 }
1947 #endif                          /* config reiserfs check */
1948
1949 /* Paste bytes to the existing item. Returns bytes number pasted into the item. */
1950 int reiserfs_paste_into_item(struct reiserfs_transaction_handle *th, struct treepath *search_path,      /* Path to the pasted item.       */
1951                              const struct cpu_key *key, /* Key to search for the needed item. */
1952                              struct inode *inode,       /* Inode item belongs to */
1953                              const char *body,  /* Pointer to the bytes to paste.    */
1954                              int pasted_size)
1955 {                               /* Size of pasted bytes.             */
1956         struct tree_balance s_paste_balance;
1957         int retval;
1958         int fs_gen;
1959
1960         BUG_ON(!th->t_trans_id);
1961
1962         fs_gen = get_generation(inode->i_sb);
1963
1964 #ifdef REISERQUOTA_DEBUG
1965         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
1966                        "reiserquota paste_into_item(): allocating %u id=%u type=%c",
1967                        pasted_size, inode->i_uid,
1968                        key2type(&(key->on_disk_key)));
1969 #endif
1970
1971         reiserfs_write_unlock(inode->i_sb);
1972         retval = dquot_alloc_space_nodirty(inode, pasted_size);
1973         reiserfs_write_lock(inode->i_sb);
1974         if (retval) {
1975                 pathrelse(search_path);
1976                 return retval;
1977         }
1978         init_tb_struct(th, &s_paste_balance, th->t_super, search_path,
1979                        pasted_size);
1980 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
1981         s_paste_balance.key = key->on_disk_key;
1982 #endif
1983
1984         /* DQUOT_* can schedule, must check before the fix_nodes */
1985         if (fs_changed(fs_gen, inode->i_sb)) {
1986                 goto search_again;
1987         }
1988
1989         while ((retval =
1990                 fix_nodes(M_PASTE, &s_paste_balance, NULL,
1991                           body)) == REPEAT_SEARCH) {
1992               search_again:
1993                 /* file system changed while we were in the fix_nodes */
1994                 PROC_INFO_INC(th->t_super, paste_into_item_restarted);
1995                 retval =
1996                     search_for_position_by_key(th->t_super, key,
1997                                                search_path);
1998                 if (retval == IO_ERROR) {
1999                         retval = -EIO;
2000                         goto error_out;
2001                 }
2002                 if (retval == POSITION_FOUND) {
2003                         reiserfs_warning(inode->i_sb, "PAP-5710",
2004                                          "entry or pasted byte (%K) exists",
2005                                          key);
2006                         retval = -EEXIST;
2007                         goto error_out;
2008                 }
2009 #ifdef CONFIG_REISERFS_CHECK
2010                 check_research_for_paste(search_path, key);
2011 #endif
2012         }
2013
2014         /* Perform balancing after all resources are collected by fix_nodes, and
2015            accessing them will not risk triggering schedule. */
2016         if (retval == CARRY_ON) {
2017                 do_balance(&s_paste_balance, NULL /*ih */ , body, M_PASTE);
2018                 return 0;
2019         }
2020         retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
2021       error_out:
2022         /* this also releases the path */
2023         unfix_nodes(&s_paste_balance);
2024 #ifdef REISERQUOTA_DEBUG
2025         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
2026                        "reiserquota paste_into_item(): freeing %u id=%u type=%c",
2027                        pasted_size, inode->i_uid,
2028                        key2type(&(key->on_disk_key)));
2029 #endif
2030         dquot_free_space_nodirty(inode, pasted_size);
2031         return retval;
2032 }
2033
2034 /* Insert new item into the buffer at the path.
2035  * th   - active transaction handle
2036  * path - path to the inserted item
2037  * ih   - pointer to the item header to insert
2038  * body - pointer to the bytes to insert
2039  */
2040 int reiserfs_insert_item(struct reiserfs_transaction_handle *th,
2041                          struct treepath *path, const struct cpu_key *key,
2042                          struct item_head *ih, struct inode *inode,
2043                          const char *body)
2044 {
2045         struct tree_balance s_ins_balance;
2046         int retval;
2047         int fs_gen = 0;
2048         int quota_bytes = 0;
2049
2050         BUG_ON(!th->t_trans_id);
2051
2052         if (inode) {            /* Do we count quotas for item? */
2053                 fs_gen = get_generation(inode->i_sb);
2054                 quota_bytes = ih_item_len(ih);
2055
2056                 /* hack so the quota code doesn't have to guess if the file has
2057                  ** a tail, links are always tails, so there's no guessing needed
2058                  */
2059                 if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(ih))
2060                         quota_bytes = inode->i_sb->s_blocksize + UNFM_P_SIZE;
2061 #ifdef REISERQUOTA_DEBUG
2062                 reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
2063                                "reiserquota insert_item(): allocating %u id=%u type=%c",
2064                                quota_bytes, inode->i_uid, head2type(ih));
2065 #endif
2066                 reiserfs_write_unlock(inode->i_sb);
2067                 /* We can't dirty inode here. It would be immediately written but
2068                  * appropriate stat item isn't inserted yet... */
2069                 retval = dquot_alloc_space_nodirty(inode, quota_bytes);
2070                 reiserfs_write_lock(inode->i_sb);
2071                 if (retval) {
2072                         pathrelse(path);
2073                         return retval;
2074                 }
2075         }
2076         init_tb_struct(th, &s_ins_balance, th->t_super, path,
2077                        IH_SIZE + ih_item_len(ih));
2078 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
2079         s_ins_balance.key = key->on_disk_key;
2080 #endif
2081         /* DQUOT_* can schedule, must check to be sure calling fix_nodes is safe */
2082         if (inode && fs_changed(fs_gen, inode->i_sb)) {
2083                 goto search_again;
2084         }
2085
2086         while ((retval =
2087                 fix_nodes(M_INSERT, &s_ins_balance, ih,
2088                           body)) == REPEAT_SEARCH) {
2089               search_again:
2090                 /* file system changed while we were in the fix_nodes */
2091                 PROC_INFO_INC(th->t_super, insert_item_restarted);
2092                 retval = search_item(th->t_super, key, path);
2093                 if (retval == IO_ERROR) {
2094                         retval = -EIO;
2095                         goto error_out;
2096                 }
2097                 if (retval == ITEM_FOUND) {
2098                         reiserfs_warning(th->t_super, "PAP-5760",
2099                                          "key %K already exists in the tree",
2100                                          key);
2101                         retval = -EEXIST;
2102                         goto error_out;
2103                 }
2104         }
2105
2106         /* make balancing after all resources will be collected at a time */
2107         if (retval == CARRY_ON) {
2108                 do_balance(&s_ins_balance, ih, body, M_INSERT);
2109                 return 0;
2110         }
2111
2112         retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
2113       error_out:
2114         /* also releases the path */
2115         unfix_nodes(&s_ins_balance);
2116 #ifdef REISERQUOTA_DEBUG
2117         reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
2118                        "reiserquota insert_item(): freeing %u id=%u type=%c",
2119                        quota_bytes, inode->i_uid, head2type(ih));
2120 #endif
2121         if (inode)
2122                 dquot_free_space_nodirty(inode, quota_bytes);
2123         return retval;
2124 }