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  * decrement_counters_in_path
  27  * reiserfs_check_path
  28  * pathrelse_and_restore
  29  * pathrelse
  30  * search_by_key_reada
  31  * search_by_key
  32  * search_for_position_by_key
  33  * comp_items
  34  * prepare_for_direct_item
  35  * prepare_for_direntry_item
  36  * prepare_for_delete_or_cut
  37  * calc_deleted_bytes_number
  38  * init_tb_struct
  39  * padd_item
  40  * reiserfs_delete_item
  41  * reiserfs_delete_solid_item
  42  * reiserfs_delete_object
  43  * maybe_indirect_to_direct
  44  * indirect_to_direct_roll_back
  45  * reiserfs_cut_from_item
  46  * truncate_directory
  47  * reiserfs_do_truncate
  48  * reiserfs_paste_into_item
  49  * reiserfs_insert_item
  50  */
  51
  52 #include <linux/config.h>
  53 #include <linux/time.h>
  54 #include <linux/string.h>
  55 #include <linux/pagemap.h>
  56 #include <linux/reiserfs_fs.h>
  57 #include <linux/smp_lock.h>
  58 #include <linux/buffer_head.h>
  59 #include <linux/quotaops.h>
  60
  61 /* Does the buffer contain a disk block which is in the tree. */
  62 inline int B_IS_IN_TREE(const struct buffer_head *p_s_bh)
  63 {
  64
  65         RFALSE(B_LEVEL(p_s_bh) > MAX_HEIGHT,
  66                "PAP-1010: block (%b) has too big level (%z)", p_s_bh, p_s_bh);
  67
  68         return (B_LEVEL(p_s_bh) != FREE_LEVEL);
  69 }
  70
  71 //
  72 // to gets item head in le form
  73 //
  74 inline void copy_item_head(struct item_head *p_v_to,
  75                            const struct item_head *p_v_from)
  76 {
  77         memcpy(p_v_to, p_v_from, IH_SIZE);
  78 }
  79
  80 /* k1 is pointer to on-disk structure which is stored in little-endian
  81    form. k2 is pointer to cpu variable. For key of items of the same
  82    object this returns 0.
  83    Returns: -1 if key1 < key2
  84    0 if key1 == key2
  85    1 if key1 > key2 */
  86 inline int comp_short_keys(const struct reiserfs_key *le_key,
  87                            const struct cpu_key *cpu_key)
  88 {
  89         __u32 n;
  90         n = le32_to_cpu(le_key->k_dir_id);
  91         if (n < cpu_key->on_disk_key.k_dir_id)
  92                 return -1;
  93         if (n > cpu_key->on_disk_key.k_dir_id)
  94                 return 1;
  95         n = le32_to_cpu(le_key->k_objectid);
  96         if (n < cpu_key->on_disk_key.k_objectid)
  97                 return -1;
  98         if (n > cpu_key->on_disk_key.k_objectid)
  99                 return 1;
 100         return 0;
 101 }
 102
 103 /* k1 is pointer to on-disk structure which is stored in little-endian
 104    form. k2 is pointer to cpu variable.
 105    Compare keys using all 4 key fields.
 106    Returns: -1 if key1 < key2 0
 107    if key1 = key2 1 if key1 > key2 */
 108 static inline int comp_keys(const struct reiserfs_key *le_key,
 109                             const struct cpu_key *cpu_key)
 110 {
 111         int retval;
 112
 113         retval = comp_short_keys(le_key, cpu_key);
 114         if (retval)
 115                 return retval;
 116         if (le_key_k_offset(le_key_version(le_key), le_key) <
 117             cpu_key_k_offset(cpu_key))
 118                 return -1;
 119         if (le_key_k_offset(le_key_version(le_key), le_key) >
 120             cpu_key_k_offset(cpu_key))
 121                 return 1;
 122
 123         if (cpu_key->key_length == 3)
 124                 return 0;
 125
 126         /* this part is needed only when tail conversion is in progress */
 127         if (le_key_k_type(le_key_version(le_key), le_key) <
 128             cpu_key_k_type(cpu_key))
 129                 return -1;
 130
 131         if (le_key_k_type(le_key_version(le_key), le_key) >
 132             cpu_key_k_type(cpu_key))
 133                 return 1;
 134
 135         return 0;
 136 }
 137
 138 inline int comp_short_le_keys(const struct reiserfs_key *key1,
 139                               const struct reiserfs_key *key2)
 140 {
 141         __u32 *p_s_1_u32, *p_s_2_u32;
 142         int n_key_length = REISERFS_SHORT_KEY_LEN;
 143
 144         p_s_1_u32 = (__u32 *) key1;
 145         p_s_2_u32 = (__u32 *) key2;
 146         for (; n_key_length--; ++p_s_1_u32, ++p_s_2_u32) {
 147                 if (le32_to_cpu(*p_s_1_u32) < le32_to_cpu(*p_s_2_u32))
 148                         return -1;
 149                 if (le32_to_cpu(*p_s_1_u32) > le32_to_cpu(*p_s_2_u32))
 150                         return 1;
 151         }
 152         return 0;
 153 }
 154
 155 inline void le_key2cpu_key(struct cpu_key *to, const struct reiserfs_key *from)
 156 {
 157         int version;
 158         to->on_disk_key.k_dir_id = le32_to_cpu(from->k_dir_id);
 159         to->on_disk_key.k_objectid = le32_to_cpu(from->k_objectid);
 160
 161         // find out version of the key
 162         version = le_key_version(from);
 163         to->version = version;
 164         to->on_disk_key.k_offset = le_key_k_offset(version, from);
 165         to->on_disk_key.k_type = le_key_k_type(version, from);
 166 }
 167
 168 // this does not say which one is bigger, it only returns 1 if keys
 169 // are not equal, 0 otherwise
 170 inline int comp_le_keys(const struct reiserfs_key *k1,
 171                         const struct reiserfs_key *k2)
 172 {
 173         return memcmp(k1, k2, sizeof(struct reiserfs_key));
 174 }
 175
 176 /**************************************************************************
 177  *  Binary search toolkit function                                        *
 178  *  Search for an item in the array by the item key                       *
 179  *  Returns:    1 if found,  0 if not found;                              *
 180  *        *p_n_pos = number of the searched element if found, else the    *
 181  *        number of the first element that is larger than p_v_key.        *
 182  **************************************************************************/
 183 /* For those not familiar with binary search: n_lbound is the leftmost item that it
 184  could be, n_rbound the rightmost item that it could be.  We examine the item
 185  halfway between n_lbound and n_rbound, and that tells us either that we can increase
 186  n_lbound, or decrease n_rbound, or that we have found it, or if n_lbound <= n_rbound that
 187  there are no possible items, and we have not found it. With each examination we
 188  cut the number of possible items it could be by one more than half rounded down,
 189  or we find it. */
 190 static inline int bin_search(const void *p_v_key,       /* Key to search for.                   */
 191                              const void *p_v_base,      /* First item in the array.             */
 192                              int p_n_num,       /* Number of items in the array.        */
 193                              int p_n_width,     /* Item size in the array.
 194                                                    searched. Lest the reader be
 195                                                    confused, note that this is crafted
 196                                                    as a general function, and when it
 197                                                    is applied specifically to the array
 198                                                    of item headers in a node, p_n_width
 199                                                    is actually the item header size not
 200                                                    the item size.                      */
 201                              int *p_n_pos       /* Number of the searched for element. */
 202     )
 203 {
 204         int n_rbound, n_lbound, n_j;
 205
 206         for (n_j = ((n_rbound = p_n_num - 1) + (n_lbound = 0)) / 2;
 207              n_lbound <= n_rbound; n_j = (n_rbound + n_lbound) / 2)
 208                 switch (comp_keys
 209                         ((struct reiserfs_key *)((char *)p_v_base +
 210                                                  n_j * p_n_width),
 211                          (struct cpu_key *)p_v_key)) {
 212                 case -1:
 213                         n_lbound = n_j + 1;
 214                         continue;
 215                 case 1:
 216                         n_rbound = n_j - 1;
 217                         continue;
 218                 case 0:
 219                         *p_n_pos = n_j;
 220                         return ITEM_FOUND;      /* Key found in the array.  */
 221                 }
 222
 223         /* bin_search did not find given key, it returns position of key,
 224            that is minimal and greater than the given one. */
 225         *p_n_pos = n_lbound;
 226         return ITEM_NOT_FOUND;
 227 }
 228
 229 #ifdef CONFIG_REISERFS_CHECK
 230 extern struct tree_balance *cur_tb;
 231 #endif
 232
 233 /* Minimal possible key. It is never in the tree. */
 234 const struct reiserfs_key MIN_KEY = { 0, 0, {{0, 0},} };
 235
 236 /* Maximal possible key. It is never in the tree. */
 237 static const struct reiserfs_key MAX_KEY = {
 238         __constant_cpu_to_le32(0xffffffff),
 239         __constant_cpu_to_le32(0xffffffff),
 240         {{__constant_cpu_to_le32(0xffffffff),
 241           __constant_cpu_to_le32(0xffffffff)},}
 242 };
 243
 244 /* Get delimiting key of the buffer by looking for it in the buffers in the path, starting from the bottom
 245    of the path, and going upwards.  We must check the path's validity at each step.  If the key is not in
 246    the path, there is no delimiting key in the tree (buffer is first or last buffer in tree), and in this
 247    case we return a special key, either MIN_KEY or MAX_KEY. */
 248 static inline const struct reiserfs_key *get_lkey(const struct path
 249                                                   *p_s_chk_path,
 250                                                   const struct super_block
 251                                                   *p_s_sb)
 252 {
 253         int n_position, n_path_offset = p_s_chk_path->path_length;
 254         struct buffer_head *p_s_parent;
 255
 256         RFALSE(n_path_offset < FIRST_PATH_ELEMENT_OFFSET,
 257                "PAP-5010: invalid offset in the path");
 258
 259         /* While not higher in path than first element. */
 260         while (n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET) {
 261
 262                 RFALSE(!buffer_uptodate
 263                        (PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)),
 264                        "PAP-5020: parent is not uptodate");
 265
 266                 /* Parent at the path is not in the tree now. */
 267                 if (!B_IS_IN_TREE
 268                     (p_s_parent =
 269                      PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)))
 270                         return &MAX_KEY;
 271                 /* Check whether position in the parent is correct. */
 272                 if ((n_position =
 273                      PATH_OFFSET_POSITION(p_s_chk_path,
 274                                           n_path_offset)) >
 275                     B_NR_ITEMS(p_s_parent))
 276                         return &MAX_KEY;
 277                 /* Check whether parent at the path really points to the child. */
 278                 if (B_N_CHILD_NUM(p_s_parent, n_position) !=
 279                     PATH_OFFSET_PBUFFER(p_s_chk_path,
 280                                         n_path_offset + 1)->b_blocknr)
 281                         return &MAX_KEY;
 282                 /* Return delimiting key if position in the parent is not equal to zero. */
 283                 if (n_position)
 284                         return B_N_PDELIM_KEY(p_s_parent, n_position - 1);
 285         }
 286         /* Return MIN_KEY if we are in the root of the buffer tree. */
 287         if (PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)->
 288             b_blocknr == SB_ROOT_BLOCK(p_s_sb))
 289                 return &MIN_KEY;
 290         return &MAX_KEY;
 291 }
 292
 293 /* Get delimiting key of the buffer at the path and its right neighbor. */
 294 inline const struct reiserfs_key *get_rkey(const struct path *p_s_chk_path,
 295                                            const struct super_block *p_s_sb)
 296 {
 297         int n_position, n_path_offset = p_s_chk_path->path_length;
 298         struct buffer_head *p_s_parent;
 299
 300         RFALSE(n_path_offset < FIRST_PATH_ELEMENT_OFFSET,
 301                "PAP-5030: invalid offset in the path");
 302
 303         while (n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET) {
 304
 305                 RFALSE(!buffer_uptodate
 306                        (PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)),
 307                        "PAP-5040: parent is not uptodate");
 308
 309                 /* Parent at the path is not in the tree now. */
 310                 if (!B_IS_IN_TREE
 311                     (p_s_parent =
 312                      PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)))
 313                         return &MIN_KEY;
 314                 /* Check whether position in the parent is correct. */
 315                 if ((n_position =
 316                      PATH_OFFSET_POSITION(p_s_chk_path,
 317                                           n_path_offset)) >
 318                     B_NR_ITEMS(p_s_parent))
 319                         return &MIN_KEY;
 320                 /* Check whether parent at the path really points to the child. */
 321                 if (B_N_CHILD_NUM(p_s_parent, n_position) !=
 322                     PATH_OFFSET_PBUFFER(p_s_chk_path,
 323                                         n_path_offset + 1)->b_blocknr)
 324                         return &MIN_KEY;
 325                 /* Return delimiting key if position in the parent is not the last one. */
 326                 if (n_position != B_NR_ITEMS(p_s_parent))
 327                         return B_N_PDELIM_KEY(p_s_parent, n_position);
 328         }
 329         /* Return MAX_KEY if we are in the root of the buffer tree. */
 330         if (PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)->
 331             b_blocknr == SB_ROOT_BLOCK(p_s_sb))
 332                 return &MAX_KEY;
 333         return &MIN_KEY;
 334 }
 335
 336 /* Check whether a key is contained in the tree rooted from a buffer at a path. */
 337 /* This works by looking at the left and right delimiting keys for the buffer in the last path_element in
 338    the path.  These delimiting keys are stored at least one level above that buffer in the tree. If the
 339    buffer is the first or last node in the tree order then one of the delimiting keys may be absent, and in
 340    this case get_lkey and get_rkey return a special key which is MIN_KEY or MAX_KEY. */
 341 static inline int key_in_buffer(struct path *p_s_chk_path,      /* Path which should be checked.  */
 342                                 const struct cpu_key *p_s_key,  /* Key which should be checked.   */
 343                                 struct super_block *p_s_sb      /* Super block pointer.           */
 344     )
 345 {
 346
 347         RFALSE(!p_s_key || p_s_chk_path->path_length < FIRST_PATH_ELEMENT_OFFSET
 348                || p_s_chk_path->path_length > MAX_HEIGHT,
 349                "PAP-5050: pointer to the key(%p) is NULL or invalid path length(%d)",
 350                p_s_key, p_s_chk_path->path_length);
 351         RFALSE(!PATH_PLAST_BUFFER(p_s_chk_path)->b_bdev,
 352                "PAP-5060: device must not be NODEV");
 353
 354         if (comp_keys(get_lkey(p_s_chk_path, p_s_sb), p_s_key) == 1)
 355                 /* left delimiting key is bigger, that the key we look for */
 356                 return 0;
 357         //  if ( comp_keys(p_s_key, get_rkey(p_s_chk_path, p_s_sb)) != -1 )
 358         if (comp_keys(get_rkey(p_s_chk_path, p_s_sb), p_s_key) != 1)
 359                 /* p_s_key must be less than right delimitiing key */
 360                 return 0;
 361         return 1;
 362 }
 363
 364 inline void decrement_bcount(struct buffer_head *p_s_bh)
 365 {
 366         if (p_s_bh) {
 367                 if (atomic_read(&(p_s_bh->b_count))) {
 368                         put_bh(p_s_bh);
 369                         return;
 370                 }
 371                 reiserfs_panic(NULL,
 372                                "PAP-5070: decrement_bcount: trying to free free buffer %b",
 373                                p_s_bh);
 374         }
 375 }
 376
 377 /* Decrement b_count field of the all buffers in the path. */
 378 void decrement_counters_in_path(struct path *p_s_search_path)
 379 {
 380         int n_path_offset = p_s_search_path->path_length;
 381
 382         RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET ||
 383                n_path_offset > EXTENDED_MAX_HEIGHT - 1,
 384                "PAP-5080: invalid path offset of %d", n_path_offset);
 385
 386         while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) {
 387                 struct buffer_head *bh;
 388
 389                 bh = PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--);
 390                 decrement_bcount(bh);
 391         }
 392         p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
 393 }
 394
 395 int reiserfs_check_path(struct path *p)
 396 {
 397         RFALSE(p->path_length != ILLEGAL_PATH_ELEMENT_OFFSET,
 398                "path not properly relsed");
 399         return 0;
 400 }
 401
 402 /* Release all buffers in the path. Restore dirty bits clean
 403 ** when preparing the buffer for the log
 404 **
 405 ** only called from fix_nodes()
 406 */
 407 void pathrelse_and_restore(struct super_block *s, struct path *p_s_search_path)
 408 {
 409         int n_path_offset = p_s_search_path->path_length;
 410
 411         RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET,
 412                "clm-4000: invalid path offset");
 413
 414         while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) {
 415                 reiserfs_restore_prepared_buffer(s,
 416                                                  PATH_OFFSET_PBUFFER
 417                                                  (p_s_search_path,
 418                                                   n_path_offset));
 419                 brelse(PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--));
 420         }
 421         p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
 422 }
 423
 424 /* Release all buffers in the path. */
 425 void pathrelse(struct path *p_s_search_path)
 426 {
 427         int n_path_offset = p_s_search_path->path_length;
 428
 429         RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET,
 430                "PAP-5090: invalid path offset");
 431
 432         while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET)
 433                 brelse(PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--));
 434
 435         p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
 436 }
 437
 438 static int is_leaf(char *buf, int blocksize, struct buffer_head *bh)
 439 {
 440         struct block_head *blkh;
 441         struct item_head *ih;
 442         int used_space;
 443         int prev_location;
 444         int i;
 445         int nr;
 446
 447         blkh = (struct block_head *)buf;
 448         if (blkh_level(blkh) != DISK_LEAF_NODE_LEVEL) {
 449                 reiserfs_warning(NULL,
 450                                  "is_leaf: this should be caught earlier");
 451                 return 0;
 452         }
 453
 454         nr = blkh_nr_item(blkh);
 455         if (nr < 1 || nr > ((blocksize - BLKH_SIZE) / (IH_SIZE + MIN_ITEM_LEN))) {
 456                 /* item number is too big or too small */
 457                 reiserfs_warning(NULL, "is_leaf: nr_item seems wrong: %z", bh);
 458                 return 0;
 459         }
 460         ih = (struct item_head *)(buf + BLKH_SIZE) + nr - 1;
 461         used_space = BLKH_SIZE + IH_SIZE * nr + (blocksize - ih_location(ih));
 462         if (used_space != blocksize - blkh_free_space(blkh)) {
 463                 /* free space does not match to calculated amount of use space */
 464                 reiserfs_warning(NULL, "is_leaf: free space seems wrong: %z",
 465                                  bh);
 466                 return 0;
 467         }
 468         // FIXME: it is_leaf will hit performance too much - we may have
 469         // return 1 here
 470
 471         /* check tables of item heads */
 472         ih = (struct item_head *)(buf + BLKH_SIZE);
 473         prev_location = blocksize;
 474         for (i = 0; i < nr; i++, ih++) {
 475                 if (le_ih_k_type(ih) == TYPE_ANY) {
 476                         reiserfs_warning(NULL,
 477                                          "is_leaf: wrong item type for item %h",
 478                                          ih);
 479                         return 0;
 480                 }
 481                 if (ih_location(ih) >= blocksize
 482                     || ih_location(ih) < IH_SIZE * nr) {
 483                         reiserfs_warning(NULL,
 484                                          "is_leaf: item location seems wrong: %h",
 485                                          ih);
 486                         return 0;
 487                 }
 488                 if (ih_item_len(ih) < 1
 489                     || ih_item_len(ih) > MAX_ITEM_LEN(blocksize)) {
 490                         reiserfs_warning(NULL,
 491                                          "is_leaf: item length seems wrong: %h",
 492                                          ih);
 493                         return 0;
 494                 }
 495                 if (prev_location - ih_location(ih) != ih_item_len(ih)) {
 496                         reiserfs_warning(NULL,
 497                                          "is_leaf: item location seems wrong (second one): %h",
 498                                          ih);
 499                         return 0;
 500                 }
 501                 prev_location = ih_location(ih);
 502         }
 503
 504         // one may imagine much more checks
 505         return 1;
 506 }
 507
 508 /* returns 1 if buf looks like an internal node, 0 otherwise */
 509 static int is_internal(char *buf, int blocksize, struct buffer_head *bh)
 510 {
 511         struct block_head *blkh;
 512         int nr;
 513         int used_space;
 514
 515         blkh = (struct block_head *)buf;
 516         nr = blkh_level(blkh);
 517         if (nr <= DISK_LEAF_NODE_LEVEL || nr > MAX_HEIGHT) {
 518                 /* this level is not possible for internal nodes */
 519                 reiserfs_warning(NULL,
 520                                  "is_internal: this should be caught earlier");
 521                 return 0;
 522         }
 523
 524         nr = blkh_nr_item(blkh);
 525         if (nr > (blocksize - BLKH_SIZE - DC_SIZE) / (KEY_SIZE + DC_SIZE)) {
 526                 /* for internal which is not root we might check min number of keys */
 527                 reiserfs_warning(NULL,
 528                                  "is_internal: number of key seems wrong: %z",
 529                                  bh);
 530                 return 0;
 531         }
 532
 533         used_space = BLKH_SIZE + KEY_SIZE * nr + DC_SIZE * (nr + 1);
 534         if (used_space != blocksize - blkh_free_space(blkh)) {
 535                 reiserfs_warning(NULL,
 536                                  "is_internal: free space seems wrong: %z", bh);
 537                 return 0;
 538         }
 539         // one may imagine much more checks
 540         return 1;
 541 }
 542
 543 // make sure that bh contains formatted node of reiserfs tree of
 544 // 'level'-th level
 545 static int is_tree_node(struct buffer_head *bh, int level)
 546 {
 547         if (B_LEVEL(bh) != level) {
 548                 reiserfs_warning(NULL,
 549                                  "is_tree_node: node level %d does not match to the expected one %d",
 550                                  B_LEVEL(bh), level);
 551                 return 0;
 552         }
 553         if (level == DISK_LEAF_NODE_LEVEL)
 554                 return is_leaf(bh->b_data, bh->b_size, bh);
 555
 556         return is_internal(bh->b_data, bh->b_size, bh);
 557 }
 558
 559 #define SEARCH_BY_KEY_READA 16
 560
 561 /* The function is NOT SCHEDULE-SAFE! */
 562 static void search_by_key_reada(struct super_block *s,
 563                                 struct buffer_head **bh,
 564                                 unsigned long *b, int num)
 565 {
 566         int i, j;
 567
 568         for (i = 0; i < num; i++) {
 569                 bh[i] = sb_getblk(s, b[i]);
 570         }
 571         for (j = 0; j < i; j++) {
 572                 /*
 573                  * note, this needs attention if we are getting rid of the BKL
 574                  * you have to make sure the prepared bit isn't set on this buffer
 575                  */
 576                 if (!buffer_uptodate(bh[j]))
 577                         ll_rw_block(READA, 1, bh + j);
 578                 brelse(bh[j]);
 579         }
 580 }
 581
 582 /**************************************************************************
 583  * Algorithm   SearchByKey                                                *
 584  *             look for item in the Disk S+Tree by its key                *
 585  * Input:  p_s_sb   -  super block                                        *
 586  *         p_s_key  - pointer to the key to search                        *
 587  * Output: ITEM_FOUND, ITEM_NOT_FOUND or IO_ERROR                         *
 588  *         p_s_search_path - path from the root to the needed leaf        *
 589  **************************************************************************/
 590
 591 /* This function fills up the path from the root to the leaf as it
 592    descends the tree looking for the key.  It uses reiserfs_bread to
 593    try to find buffers in the cache given their block number.  If it
 594    does not find them in the cache it reads them from disk.  For each
 595    node search_by_key finds using reiserfs_bread it then uses
 596    bin_search to look through that node.  bin_search will find the
 597    position of the block_number of the next node if it is looking
 598    through an internal node.  If it is looking through a leaf node
 599    bin_search will find the position of the item which has key either
 600    equal to given key, or which is the maximal key less than the given
 601    key.  search_by_key returns a path that must be checked for the
 602    correctness of the top of the path but need not be checked for the
 603    correctness of the bottom of the path */
 604 /* The function is NOT SCHEDULE-SAFE! */
 605 int search_by_key(struct super_block *p_s_sb, const struct cpu_key *p_s_key,    /* Key to search. */
 606                   struct path *p_s_search_path, /* This structure was
 607                                                    allocated and initialized
 608                                                    by the calling
 609                                                    function. It is filled up
 610                                                    by this function.  */
 611                   int n_stop_level      /* How far down the tree to search. To
 612                                            stop at leaf level - set to
 613                                            DISK_LEAF_NODE_LEVEL */
 614     )
 615 {
 616         int n_block_number;
 617         int expected_level;
 618         struct buffer_head *p_s_bh;
 619         struct path_element *p_s_last_element;
 620         int n_node_level, n_retval;
 621         int right_neighbor_of_leaf_node;
 622         int fs_gen;
 623         struct buffer_head *reada_bh[SEARCH_BY_KEY_READA];
 624         unsigned long reada_blocks[SEARCH_BY_KEY_READA];
 625         int reada_count = 0;
 626
 627 #ifdef CONFIG_REISERFS_CHECK
 628         int n_repeat_counter = 0;
 629 #endif
 630
 631         PROC_INFO_INC(p_s_sb, search_by_key);
 632
 633         /* As we add each node to a path we increase its count.  This means that
 634            we must be careful to release all nodes in a path before we either
 635            discard the path struct or re-use the path struct, as we do here. */
 636
 637         decrement_counters_in_path(p_s_search_path);
 638
 639         right_neighbor_of_leaf_node = 0;
 640
 641         /* With each iteration of this loop we search through the items in the
 642            current node, and calculate the next current node(next path element)
 643            for the next iteration of this loop.. */
 644         n_block_number = SB_ROOT_BLOCK(p_s_sb);
 645         expected_level = -1;
 646         while (1) {
 647
 648 #ifdef CONFIG_REISERFS_CHECK
 649                 if (!(++n_repeat_counter % 50000))
 650                         reiserfs_warning(p_s_sb, "PAP-5100: search_by_key: %s:"
 651                                          "there were %d iterations of while loop "
 652                                          "looking for key %K",
 653                                          current->comm, n_repeat_counter,
 654                                          p_s_key);
 655 #endif
 656
 657                 /* prep path to have another element added to it. */
 658                 p_s_last_element =
 659                     PATH_OFFSET_PELEMENT(p_s_search_path,
 660                                          ++p_s_search_path->path_length);
 661                 fs_gen = get_generation(p_s_sb);
 662
 663                 /* Read the next tree node, and set the last element in the path to
 664                    have a pointer to it. */
 665                 if ((p_s_bh = p_s_last_element->pe_buffer =
 666                      sb_getblk(p_s_sb, n_block_number))) {
 667                         if (!buffer_uptodate(p_s_bh) && reada_count > 1) {
 668                                 search_by_key_reada(p_s_sb, reada_bh,
 669                                                     reada_blocks, reada_count);
 670                         }
 671                         ll_rw_block(READ, 1, &p_s_bh);
 672                         wait_on_buffer(p_s_bh);
 673                         if (!buffer_uptodate(p_s_bh))
 674                                 goto io_error;
 675                 } else {
 676                       io_error:
 677                         p_s_search_path->path_length--;
 678                         pathrelse(p_s_search_path);
 679                         return IO_ERROR;
 680                 }
 681                 reada_count = 0;
 682                 if (expected_level == -1)
 683                         expected_level = SB_TREE_HEIGHT(p_s_sb);
 684                 expected_level--;
 685
 686                 /* It is possible that schedule occurred. We must check whether the key
 687                    to search is still in the tree rooted from the current buffer. If
 688                    not then repeat search from the root. */
 689                 if (fs_changed(fs_gen, p_s_sb) &&
 690                     (!B_IS_IN_TREE(p_s_bh) ||
 691                      B_LEVEL(p_s_bh) != expected_level ||
 692                      !key_in_buffer(p_s_search_path, p_s_key, p_s_sb))) {
 693                         PROC_INFO_INC(p_s_sb, search_by_key_fs_changed);
 694                         PROC_INFO_INC(p_s_sb, search_by_key_restarted);
 695                         PROC_INFO_INC(p_s_sb,
 696                                       sbk_restarted[expected_level - 1]);
 697                         decrement_counters_in_path(p_s_search_path);
 698
 699                         /* Get the root block number so that we can repeat the search
 700                            starting from the root. */
 701                         n_block_number = SB_ROOT_BLOCK(p_s_sb);
 702                         expected_level = -1;
 703                         right_neighbor_of_leaf_node = 0;
 704
 705                         /* repeat search from the root */
 706                         continue;
 707                 }
 708
 709                 /* only check that the key is in the buffer if p_s_key is not
 710                    equal to the MAX_KEY. Latter case is only possible in
 711                    "finish_unfinished()" processing during mount. */
 712                 RFALSE(comp_keys(&MAX_KEY, p_s_key) &&
 713                        !key_in_buffer(p_s_search_path, p_s_key, p_s_sb),
 714                        "PAP-5130: key is not in the buffer");
 715 #ifdef CONFIG_REISERFS_CHECK
 716                 if (cur_tb) {
 717                         print_cur_tb("5140");
 718                         reiserfs_panic(p_s_sb,
 719                                        "PAP-5140: search_by_key: schedule occurred in do_balance!");
 720                 }
 721 #endif
 722
 723                 // make sure, that the node contents look like a node of
 724                 // certain level
 725                 if (!is_tree_node(p_s_bh, expected_level)) {
 726                         reiserfs_warning(p_s_sb, "vs-5150: search_by_key: "
 727                                          "invalid format found in block %ld. Fsck?",
 728                                          p_s_bh->b_blocknr);
 729                         pathrelse(p_s_search_path);
 730                         return IO_ERROR;
 731                 }
 732
 733                 /* ok, we have acquired next formatted node in the tree */
 734                 n_node_level = B_LEVEL(p_s_bh);
 735
 736                 PROC_INFO_BH_STAT(p_s_sb, p_s_bh, n_node_level - 1);
 737
 738                 RFALSE(n_node_level < n_stop_level,
 739                        "vs-5152: tree level (%d) is less than stop level (%d)",
 740                        n_node_level, n_stop_level);
 741
 742                 n_retval = bin_search(p_s_key, B_N_PITEM_HEAD(p_s_bh, 0),
 743                                       B_NR_ITEMS(p_s_bh),
 744                                       (n_node_level ==
 745                                        DISK_LEAF_NODE_LEVEL) ? IH_SIZE :
 746                                       KEY_SIZE,
 747                                       &(p_s_last_element->pe_position));
 748                 if (n_node_level == n_stop_level) {
 749                         return n_retval;
 750                 }
 751
 752                 /* we are not in the stop level */
 753                 if (n_retval == ITEM_FOUND)
 754                         /* item has been found, so we choose the pointer which is to the right of the found one */
 755                         p_s_last_element->pe_position++;
 756
 757                 /* if item was not found we choose the position which is to
 758                    the left of the found item. This requires no code,
 759                    bin_search did it already. */
 760
 761                 /* So we have chosen a position in the current node which is
 762                    an internal node.  Now we calculate child block number by
 763                    position in the node. */
 764                 n_block_number =
 765                     B_N_CHILD_NUM(p_s_bh, p_s_last_element->pe_position);
 766
 767                 /* if we are going to read leaf nodes, try for read ahead as well */
 768                 if ((p_s_search_path->reada & PATH_READA) &&
 769                     n_node_level == DISK_LEAF_NODE_LEVEL + 1) {
 770                         int pos = p_s_last_element->pe_position;
 771                         int limit = B_NR_ITEMS(p_s_bh);
 772                         struct reiserfs_key *le_key;
 773
 774                         if (p_s_search_path->reada & PATH_READA_BACK)
 775                                 limit = 0;
 776                         while (reada_count < SEARCH_BY_KEY_READA) {
 777                                 if (pos == limit)
 778                                         break;
 779                                 reada_blocks[reada_count++] =
 780                                     B_N_CHILD_NUM(p_s_bh, pos);
 781                                 if (p_s_search_path->reada & PATH_READA_BACK)
 782                                         pos--;
 783                                 else
 784                                         pos++;
 785
 786                                 /*
 787                                  * check to make sure we're in the same object
 788                                  */
 789                                 le_key = B_N_PDELIM_KEY(p_s_bh, pos);
 790                                 if (le32_to_cpu(le_key->k_objectid) !=
 791                                     p_s_key->on_disk_key.k_objectid) {
 792                                         break;
 793                                 }
 794                         }
 795                 }
 796         }
 797 }
 798
 799 /* Form the path to an item and position in this item which contains
 800    file byte defined by p_s_key. If there is no such item
 801    corresponding to the key, we point the path to the item with
 802    maximal key less than p_s_key, and *p_n_pos_in_item is set to one
 803    past the last entry/byte in the item.  If searching for entry in a
 804    directory item, and it is not found, *p_n_pos_in_item is set to one
 805    entry more than the entry with maximal key which is less than the
 806    sought key.
 807
 808    Note that if there is no entry in this same node which is one more,
 809    then we point to an imaginary entry.  for direct items, the
 810    position is in units of bytes, for indirect items the position is
 811    in units of blocknr entries, for directory items the position is in
 812    units of directory entries.  */
 813
 814 /* The function is NOT SCHEDULE-SAFE! */
 815 int search_for_position_by_key(struct super_block *p_s_sb,      /* Pointer to the super block.          */
 816                                const struct cpu_key *p_cpu_key, /* Key to search (cpu variable)         */
 817                                struct path *p_s_search_path     /* Filled up by this function.          */
 818     )
 819 {
 820         struct item_head *p_le_ih;      /* pointer to on-disk structure */
 821         int n_blk_size;
 822         loff_t item_offset, offset;
 823         struct reiserfs_dir_entry de;
 824         int retval;
 825
 826         /* If searching for directory entry. */
 827         if (is_direntry_cpu_key(p_cpu_key))
 828                 return search_by_entry_key(p_s_sb, p_cpu_key, p_s_search_path,
 829                                            &de);
 830
 831         /* If not searching for directory entry. */
 832
 833         /* If item is found. */
 834         retval = search_item(p_s_sb, p_cpu_key, p_s_search_path);
 835         if (retval == IO_ERROR)
 836                 return retval;
 837         if (retval == ITEM_FOUND) {
 838
 839                 RFALSE(!ih_item_len
 840                        (B_N_PITEM_HEAD
 841                         (PATH_PLAST_BUFFER(p_s_search_path),
 842                          PATH_LAST_POSITION(p_s_search_path))),
 843                        "PAP-5165: item length equals zero");
 844
 845                 pos_in_item(p_s_search_path) = 0;
 846                 return POSITION_FOUND;
 847         }
 848
 849         RFALSE(!PATH_LAST_POSITION(p_s_search_path),
 850                "PAP-5170: position equals zero");
 851
 852         /* Item is not found. Set path to the previous item. */
 853         p_le_ih =
 854             B_N_PITEM_HEAD(PATH_PLAST_BUFFER(p_s_search_path),
 855                            --PATH_LAST_POSITION(p_s_search_path));
 856         n_blk_size = p_s_sb->s_blocksize;
 857
 858         if (comp_short_keys(&(p_le_ih->ih_key), p_cpu_key)) {
 859                 return FILE_NOT_FOUND;
 860         }
 861         // FIXME: quite ugly this far
 862
 863         item_offset = le_ih_k_offset(p_le_ih);
 864         offset = cpu_key_k_offset(p_cpu_key);
 865
 866         /* Needed byte is contained in the item pointed to by the path. */
 867         if (item_offset <= offset &&
 868             item_offset + op_bytes_number(p_le_ih, n_blk_size) > offset) {
 869                 pos_in_item(p_s_search_path) = offset - item_offset;
 870                 if (is_indirect_le_ih(p_le_ih)) {
 871                         pos_in_item(p_s_search_path) /= n_blk_size;
 872                 }
 873                 return POSITION_FOUND;
 874         }
 875
 876         /* Needed byte is not contained in the item pointed to by the
 877            path. Set pos_in_item out of the item. */
 878         if (is_indirect_le_ih(p_le_ih))
 879                 pos_in_item(p_s_search_path) =
 880                     ih_item_len(p_le_ih) / UNFM_P_SIZE;
 881         else
 882                 pos_in_item(p_s_search_path) = ih_item_len(p_le_ih);
 883
 884         return POSITION_NOT_FOUND;
 885 }
 886
 887 /* Compare given item and item pointed to by the path. */
 888 int comp_items(const struct item_head *stored_ih, const struct path *p_s_path)
 889 {
 890         struct buffer_head *p_s_bh;
 891         struct item_head *ih;
 892
 893         /* Last buffer at the path is not in the tree. */
 894         if (!B_IS_IN_TREE(p_s_bh = PATH_PLAST_BUFFER(p_s_path)))
 895                 return 1;
 896
 897         /* Last path position is invalid. */
 898         if (PATH_LAST_POSITION(p_s_path) >= B_NR_ITEMS(p_s_bh))
 899                 return 1;
 900
 901         /* we need only to know, whether it is the same item */
 902         ih = get_ih(p_s_path);
 903         return memcmp(stored_ih, ih, IH_SIZE);
 904 }
 905
 906 /* unformatted nodes are not logged anymore, ever.  This is safe
 907 ** now
 908 */
 909 #define held_by_others(bh) (atomic_read(&(bh)->b_count) > 1)
 910
 911 // block can not be forgotten as it is in I/O or held by someone
 912 #define block_in_use(bh) (buffer_locked(bh) || (held_by_others(bh)))
 913
 914 // prepare for delete or cut of direct item
 915 static inline int prepare_for_direct_item(struct path *path,
 916                                           struct item_head *le_ih,
 917                                           struct inode *inode,
 918                                           loff_t new_file_length, int *cut_size)
 919 {
 920         loff_t round_len;
 921
 922         if (new_file_length == max_reiserfs_offset(inode)) {
 923                 /* item has to be deleted */
 924                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 925                 return M_DELETE;
 926         }
 927         // new file gets truncated
 928         if (get_inode_item_key_version(inode) == KEY_FORMAT_3_6) {
 929                 //
 930                 round_len = ROUND_UP(new_file_length);
 931                 /* this was n_new_file_length < le_ih ... */
 932                 if (round_len < le_ih_k_offset(le_ih)) {
 933                         *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 934                         return M_DELETE;        /* Delete this item. */
 935                 }
 936                 /* Calculate first position and size for cutting from item. */
 937                 pos_in_item(path) = round_len - (le_ih_k_offset(le_ih) - 1);
 938                 *cut_size = -(ih_item_len(le_ih) - pos_in_item(path));
 939
 940                 return M_CUT;   /* Cut from this item. */
 941         }
 942
 943         // old file: items may have any length
 944
 945         if (new_file_length < le_ih_k_offset(le_ih)) {
 946                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 947                 return M_DELETE;        /* Delete this item. */
 948         }
 949         /* Calculate first position and size for cutting from item. */
 950         *cut_size = -(ih_item_len(le_ih) -
 951                       (pos_in_item(path) =
 952                        new_file_length + 1 - le_ih_k_offset(le_ih)));
 953         return M_CUT;           /* Cut from this item. */
 954 }
 955
 956 static inline int prepare_for_direntry_item(struct path *path,
 957                                             struct item_head *le_ih,
 958                                             struct inode *inode,
 959                                             loff_t new_file_length,
 960                                             int *cut_size)
 961 {
 962         if (le_ih_k_offset(le_ih) == DOT_OFFSET &&
 963             new_file_length == max_reiserfs_offset(inode)) {
 964                 RFALSE(ih_entry_count(le_ih) != 2,
 965                        "PAP-5220: incorrect empty directory item (%h)", le_ih);
 966                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 967                 return M_DELETE;        /* Delete the directory item containing "." and ".." entry. */
 968         }
 969
 970         if (ih_entry_count(le_ih) == 1) {
 971                 /* Delete the directory item such as there is one record only
 972                    in this item */
 973                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
 974                 return M_DELETE;
 975         }
 976
 977         /* Cut one record from the directory item. */
 978         *cut_size =
 979             -(DEH_SIZE +
 980               entry_length(get_last_bh(path), le_ih, pos_in_item(path)));
 981         return M_CUT;
 982 }
 983
 984 /*  If the path points to a directory or direct item, calculate mode and the size cut, for balance.
 985     If the path points to an indirect item, remove some number of its unformatted nodes.
 986     In case of file truncate calculate whether this item must be deleted/truncated or last
 987     unformatted node of this item will be converted to a direct item.
 988     This function returns a determination of what balance mode the calling function should employ. */
 989 static char prepare_for_delete_or_cut(struct reiserfs_transaction_handle *th, struct inode *inode, struct path *p_s_path, const struct cpu_key *p_s_item_key, int *p_n_removed, /* Number of unformatted nodes which were removed
 990                                                                                                                                                                                    from end of the file. */
 991                                       int *p_n_cut_size, unsigned long long n_new_file_length   /* MAX_KEY_OFFSET in case of delete. */
 992     )
 993 {
 994         struct super_block *p_s_sb = inode->i_sb;
 995         struct item_head *p_le_ih = PATH_PITEM_HEAD(p_s_path);
 996         struct buffer_head *p_s_bh = PATH_PLAST_BUFFER(p_s_path);
 997
 998         BUG_ON(!th->t_trans_id);
 999
1000         /* Stat_data item. */
1001         if (is_statdata_le_ih(p_le_ih)) {
1002
1003                 RFALSE(n_new_file_length != max_reiserfs_offset(inode),
1004                        "PAP-5210: mode must be M_DELETE");
1005
1006                 *p_n_cut_size = -(IH_SIZE + ih_item_len(p_le_ih));
1007                 return M_DELETE;
1008         }
1009
1010         /* Directory item. */
1011         if (is_direntry_le_ih(p_le_ih))
1012                 return prepare_for_direntry_item(p_s_path, p_le_ih, inode,
1013                                                  n_new_file_length,
1014                                                  p_n_cut_size);
1015
1016         /* Direct item. */
1017         if (is_direct_le_ih(p_le_ih))
1018                 return prepare_for_direct_item(p_s_path, p_le_ih, inode,
1019                                                n_new_file_length, p_n_cut_size);
1020
1021         /* Case of an indirect item. */
1022         {
1023                 int n_unfm_number,      /* Number of the item unformatted nodes. */
1024                  n_counter, n_blk_size;
1025                 __le32 *p_n_unfm_pointer;       /* Pointer to the unformatted node number. */
1026                 __u32 tmp;
1027                 struct item_head s_ih;  /* Item header. */
1028                 char c_mode;    /* Returned mode of the balance. */
1029                 int need_research;
1030
1031                 n_blk_size = p_s_sb->s_blocksize;
1032
1033                 /* Search for the needed object indirect item until there are no unformatted nodes to be removed. */
1034                 do {
1035                         need_research = 0;
1036                         p_s_bh = PATH_PLAST_BUFFER(p_s_path);
1037                         /* Copy indirect item header to a temp variable. */
1038                         copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path));
1039                         /* Calculate number of unformatted nodes in this item. */
1040                         n_unfm_number = I_UNFM_NUM(&s_ih);
1041
1042                         RFALSE(!is_indirect_le_ih(&s_ih) || !n_unfm_number ||
1043                                pos_in_item(p_s_path) + 1 != n_unfm_number,
1044                                "PAP-5240: invalid item %h "
1045                                "n_unfm_number = %d *p_n_pos_in_item = %d",
1046                                &s_ih, n_unfm_number, pos_in_item(p_s_path));
1047
1048                         /* Calculate balance mode and position in the item to remove unformatted nodes. */
1049                         if (n_new_file_length == max_reiserfs_offset(inode)) {  /* Case of delete. */
1050                                 pos_in_item(p_s_path) = 0;
1051                                 *p_n_cut_size = -(IH_SIZE + ih_item_len(&s_ih));
1052                                 c_mode = M_DELETE;
1053                         } else {        /* Case of truncate. */
1054                                 if (n_new_file_length < le_ih_k_offset(&s_ih)) {
1055                                         pos_in_item(p_s_path) = 0;
1056                                         *p_n_cut_size =
1057                                             -(IH_SIZE + ih_item_len(&s_ih));
1058                                         c_mode = M_DELETE;      /* Delete this item. */
1059                                 } else {
1060                                         /* indirect item must be truncated starting from *p_n_pos_in_item-th position */
1061                                         pos_in_item(p_s_path) =
1062                                             (n_new_file_length + n_blk_size -
1063                                              le_ih_k_offset(&s_ih)) >> p_s_sb->
1064                                             s_blocksize_bits;
1065
1066                                         RFALSE(pos_in_item(p_s_path) >
1067                                                n_unfm_number,
1068                                                "PAP-5250: invalid position in the item");
1069
1070                                         /* Either convert last unformatted node of indirect item to direct item or increase
1071                                            its free space.  */
1072                                         if (pos_in_item(p_s_path) ==
1073                                             n_unfm_number) {
1074                                                 *p_n_cut_size = 0;      /* Nothing to cut. */
1075                                                 return M_CONVERT;       /* Maybe convert last unformatted node to the direct item. */
1076                                         }
1077                                         /* Calculate size to cut. */
1078                                         *p_n_cut_size =
1079                                             -(ih_item_len(&s_ih) -
1080                                               pos_in_item(p_s_path) *
1081                                               UNFM_P_SIZE);
1082
1083                                         c_mode = M_CUT; /* Cut from this indirect item. */
1084                                 }
1085                         }
1086
1087                         RFALSE(n_unfm_number <= pos_in_item(p_s_path),
1088                                "PAP-5260: invalid position in the indirect item");
1089
1090                         /* pointers to be cut */
1091                         n_unfm_number -= pos_in_item(p_s_path);
1092                         /* Set pointer to the last unformatted node pointer that is to be cut. */
1093                         p_n_unfm_pointer =
1094                             (__le32 *) B_I_PITEM(p_s_bh,
1095                                                  &s_ih) + I_UNFM_NUM(&s_ih) -
1096                             1 - *p_n_removed;
1097
1098                         /* We go through the unformatted nodes pointers of the indirect
1099                            item and look for the unformatted nodes in the cache. If we
1100                            found some of them we free it, zero corresponding indirect item
1101                            entry and log buffer containing that indirect item. For this we
1102                            need to prepare last path element for logging. If some
1103                            unformatted node has b_count > 1 we must not free this
1104                            unformatted node since it is in use. */
1105                         reiserfs_prepare_for_journal(p_s_sb, p_s_bh, 1);
1106                         // note: path could be changed, first line in for loop takes care
1107                         // of it
1108
1109                         for (n_counter = *p_n_removed;
1110                              n_counter < n_unfm_number;
1111                              n_counter++, p_n_unfm_pointer--) {
1112
1113                                 cond_resched();
1114                                 if (item_moved(&s_ih, p_s_path)) {
1115                                         need_research = 1;
1116                                         break;
1117                                 }
1118                                 RFALSE(p_n_unfm_pointer <
1119                                        (__le32 *) B_I_PITEM(p_s_bh, &s_ih)
1120                                        || p_n_unfm_pointer >
1121                                        (__le32 *) B_I_PITEM(p_s_bh,
1122                                                             &s_ih) +
1123                                        I_UNFM_NUM(&s_ih) - 1,
1124                                        "vs-5265: pointer out of range");
1125
1126                                 /* Hole, nothing to remove. */
1127                                 if (!get_block_num(p_n_unfm_pointer, 0)) {
1128                                         (*p_n_removed)++;
1129                                         continue;
1130                                 }
1131
1132                                 (*p_n_removed)++;
1133
1134                                 tmp = get_block_num(p_n_unfm_pointer, 0);
1135                                 put_block_num(p_n_unfm_pointer, 0, 0);
1136                                 journal_mark_dirty(th, p_s_sb, p_s_bh);
1137                                 reiserfs_free_block(th, inode, tmp, 1);
1138                                 if (item_moved(&s_ih, p_s_path)) {
1139                                         need_research = 1;
1140                                         break;
1141                                 }
1142                         }
1143
1144                         /* a trick.  If the buffer has been logged, this
1145                          ** will do nothing.  If we've broken the loop without
1146                          ** logging it, it will restore the buffer
1147                          **
1148                          */
1149                         reiserfs_restore_prepared_buffer(p_s_sb, p_s_bh);
1150
1151                         /* This loop can be optimized. */
1152                 } while ((*p_n_removed < n_unfm_number || need_research) &&
1153                          search_for_position_by_key(p_s_sb, p_s_item_key,
1154                                                     p_s_path) ==
1155                          POSITION_FOUND);
1156
1157                 RFALSE(*p_n_removed < n_unfm_number,
1158                        "PAP-5310: indirect item is not found");
1159                 RFALSE(item_moved(&s_ih, p_s_path),
1160                        "after while, comp failed, retry");
1161
1162                 if (c_mode == M_CUT)
1163                         pos_in_item(p_s_path) *= UNFM_P_SIZE;
1164                 return c_mode;
1165         }
1166 }
1167
1168 /* Calculate number of bytes which will be deleted or cut during balance */
1169 static int calc_deleted_bytes_number(struct tree_balance *p_s_tb, char c_mode)
1170 {
1171         int n_del_size;
1172         struct item_head *p_le_ih = PATH_PITEM_HEAD(p_s_tb->tb_path);
1173
1174         if (is_statdata_le_ih(p_le_ih))
1175                 return 0;
1176
1177         n_del_size =
1178             (c_mode ==
1179              M_DELETE) ? ih_item_len(p_le_ih) : -p_s_tb->insert_size[0];
1180         if (is_direntry_le_ih(p_le_ih)) {
1181                 // return EMPTY_DIR_SIZE; /* We delete emty directoris only. */
1182                 // we can't use EMPTY_DIR_SIZE, as old format dirs have a different
1183                 // empty size.  ick. FIXME, is this right?
1184                 //
1185                 return n_del_size;
1186         }
1187
1188         if (is_indirect_le_ih(p_le_ih))
1189                 n_del_size = (n_del_size / UNFM_P_SIZE) * (PATH_PLAST_BUFFER(p_s_tb->tb_path)->b_size); // - get_ih_free_space (p_le_ih);
1190         return n_del_size;
1191 }
1192
1193 static void init_tb_struct(struct reiserfs_transaction_handle *th,
1194                            struct tree_balance *p_s_tb,
1195                            struct super_block *p_s_sb,
1196                            struct path *p_s_path, int n_size)
1197 {
1198
1199         BUG_ON(!th->t_trans_id);
1200
1201         memset(p_s_tb, '\0', sizeof(struct tree_balance));
1202         p_s_tb->transaction_handle = th;
1203         p_s_tb->tb_sb = p_s_sb;
1204         p_s_tb->tb_path = p_s_path;
1205         PATH_OFFSET_PBUFFER(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = NULL;
1206         PATH_OFFSET_POSITION(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = 0;
1207         p_s_tb->insert_size[0] = n_size;
1208 }
1209
1210 void padd_item(char *item, int total_length, int length)
1211 {
1212         int i;
1213
1214         for (i = total_length; i > length;)
1215                 item[--i] = 0;
1216 }
1217
1218 #ifdef REISERQUOTA_DEBUG
1219 char key2type(struct reiserfs_key *ih)
1220 {
1221         if (is_direntry_le_key(2, ih))
1222                 return 'd';
1223         if (is_direct_le_key(2, ih))
1224                 return 'D';
1225         if (is_indirect_le_key(2, ih))
1226                 return 'i';
1227         if (is_statdata_le_key(2, ih))
1228                 return 's';
1229         return 'u';
1230 }
1231
1232 char head2type(struct item_head *ih)
1233 {
1234         if (is_direntry_le_ih(ih))
1235                 return 'd';
1236         if (is_direct_le_ih(ih))
1237                 return 'D';
1238         if (is_indirect_le_ih(ih))
1239                 return 'i';
1240         if (is_statdata_le_ih(ih))
1241                 return 's';
1242         return 'u';
1243 }
1244 #endif
1245
1246 /* Delete object item. */
1247 int reiserfs_delete_item(struct reiserfs_transaction_handle *th, struct path *p_s_path, /* Path to the deleted item. */
1248                          const struct cpu_key *p_s_item_key,    /* Key to search for the deleted item.  */
1249                          struct inode *p_s_inode,       /* inode is here just to update i_blocks and quotas */
1250                          struct buffer_head *p_s_un_bh)
1251 {                               /* NULL or unformatted node pointer.    */
1252         struct super_block *p_s_sb = p_s_inode->i_sb;
1253         struct tree_balance s_del_balance;
1254         struct item_head s_ih;
1255         struct item_head *q_ih;
1256         int quota_cut_bytes;
1257         int n_ret_value, n_del_size, n_removed;
1258
1259 #ifdef CONFIG_REISERFS_CHECK
1260         char c_mode;
1261         int n_iter = 0;
1262 #endif
1263
1264         BUG_ON(!th->t_trans_id);
1265
1266         init_tb_struct(th, &s_del_balance, p_s_sb, p_s_path,
1267                        0 /*size is unknown */ );
1268
1269         while (1) {
1270                 n_removed = 0;
1271
1272 #ifdef CONFIG_REISERFS_CHECK
1273                 n_iter++;
1274                 c_mode =
1275 #endif
1276                     prepare_for_delete_or_cut(th, p_s_inode, p_s_path,
1277                                               p_s_item_key, &n_removed,
1278                                               &n_del_size,
1279                                               max_reiserfs_offset(p_s_inode));
1280
1281                 RFALSE(c_mode != M_DELETE, "PAP-5320: mode must be M_DELETE");
1282
1283                 copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path));
1284                 s_del_balance.insert_size[0] = n_del_size;
1285
1286                 n_ret_value = fix_nodes(M_DELETE, &s_del_balance, NULL, NULL);
1287                 if (n_ret_value != REPEAT_SEARCH)
1288                         break;
1289
1290                 PROC_INFO_INC(p_s_sb, delete_item_restarted);
1291
1292                 // file system changed, repeat search
1293                 n_ret_value =
1294                     search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path);
1295                 if (n_ret_value == IO_ERROR)
1296                         break;
1297                 if (n_ret_value == FILE_NOT_FOUND) {
1298                         reiserfs_warning(p_s_sb,
1299                                          "vs-5340: reiserfs_delete_item: "
1300                                          "no items of the file %K found",
1301                                          p_s_item_key);
1302                         break;
1303                 }
1304         }                       /* while (1) */
1305
1306         if (n_ret_value != CARRY_ON) {
1307                 unfix_nodes(&s_del_balance);
1308                 return 0;
1309         }
1310         // reiserfs_delete_item returns item length when success
1311         n_ret_value = calc_deleted_bytes_number(&s_del_balance, M_DELETE);
1312         q_ih = get_ih(p_s_path);
1313         quota_cut_bytes = ih_item_len(q_ih);
1314
1315         /* hack so the quota code doesn't have to guess if the file
1316          ** has a tail.  On tail insert, we allocate quota for 1 unformatted node.
1317          ** We test the offset because the tail might have been
1318          ** split into multiple items, and we only want to decrement for
1319          ** the unfm node once
1320          */
1321         if (!S_ISLNK(p_s_inode->i_mode) && is_direct_le_ih(q_ih)) {
1322                 if ((le_ih_k_offset(q_ih) & (p_s_sb->s_blocksize - 1)) == 1) {
1323                         quota_cut_bytes = p_s_sb->s_blocksize + UNFM_P_SIZE;
1324                 } else {
1325                         quota_cut_bytes = 0;
1326                 }
1327         }
1328
1329         if (p_s_un_bh) {
1330                 int off;
1331                 char *data;
1332
1333                 /* We are in direct2indirect conversion, so move tail contents
1334                    to the unformatted node */
1335                 /* note, we do the copy before preparing the buffer because we
1336                  ** don't care about the contents of the unformatted node yet.
1337                  ** the only thing we really care about is the direct item's data
1338                  ** is in the unformatted node.
1339                  **
1340                  ** Otherwise, we would have to call reiserfs_prepare_for_journal on
1341                  ** the unformatted node, which might schedule, meaning we'd have to
1342                  ** loop all the way back up to the start of the while loop.
1343                  **
1344                  ** The unformatted node must be dirtied later on.  We can't be
1345                  ** sure here if the entire tail has been deleted yet.
1346                  **
1347                  ** p_s_un_bh is from the page cache (all unformatted nodes are
1348                  ** from the page cache) and might be a highmem page.  So, we
1349                  ** can't use p_s_un_bh->b_data.
1350                  ** -clm
1351                  */
1352
1353                 data = kmap_atomic(p_s_un_bh->b_page, KM_USER0);
1354                 off = ((le_ih_k_offset(&s_ih) - 1) & (PAGE_CACHE_SIZE - 1));
1355                 memcpy(data + off,
1356                        B_I_PITEM(PATH_PLAST_BUFFER(p_s_path), &s_ih),
1357                        n_ret_value);
1358                 kunmap_atomic(data, KM_USER0);
1359         }
1360         /* Perform balancing after all resources have been collected at once. */
1361         do_balance(&s_del_balance, NULL, NULL, M_DELETE);
1362
1363 #ifdef REISERQUOTA_DEBUG
1364         reiserfs_debug(p_s_sb, REISERFS_DEBUG_CODE,
1365                        "reiserquota delete_item(): freeing %u, id=%u type=%c",
1366                        quota_cut_bytes, p_s_inode->i_uid, head2type(&s_ih));
1367 #endif
1368         DQUOT_FREE_SPACE_NODIRTY(p_s_inode, quota_cut_bytes);
1369
1370         /* Return deleted body length */
1371         return n_ret_value;
1372 }
1373
1374 /* Summary Of Mechanisms For Handling Collisions Between Processes:
1375
1376  deletion of the body of the object is performed by iput(), with the
1377  result that if multiple processes are operating on a file, the
1378  deletion of the body of the file is deferred until the last process
1379  that has an open inode performs its iput().
1380
1381  writes and truncates are protected from collisions by use of
1382  semaphores.
1383
1384  creates, linking, and mknod are protected from collisions with other
1385  processes by making the reiserfs_add_entry() the last step in the
1386  creation, and then rolling back all changes if there was a collision.
1387  - Hans
1388 */
1389
1390 /* this deletes item which never gets split */
1391 void reiserfs_delete_solid_item(struct reiserfs_transaction_handle *th,
1392                                 struct inode *inode, struct reiserfs_key *key)
1393 {
1394         struct tree_balance tb;
1395         INITIALIZE_PATH(path);
1396         int item_len = 0;
1397         int tb_init = 0;
1398         struct cpu_key cpu_key;
1399         int retval;
1400         int quota_cut_bytes = 0;
1401
1402         BUG_ON(!th->t_trans_id);
1403
1404         le_key2cpu_key(&cpu_key, key);
1405
1406         while (1) {
1407                 retval = search_item(th->t_super, &cpu_key, &path);
1408                 if (retval == IO_ERROR) {
1409                         reiserfs_warning(th->t_super,
1410                                          "vs-5350: reiserfs_delete_solid_item: "
1411                                          "i/o failure occurred trying to delete %K",
1412                                          &cpu_key);
1413                         break;
1414                 }
1415                 if (retval != ITEM_FOUND) {
1416                         pathrelse(&path);
1417                         // No need for a warning, if there is just no free space to insert '..' item into the newly-created subdir
1418                         if (!
1419                             ((unsigned long long)
1420                              GET_HASH_VALUE(le_key_k_offset
1421                                             (le_key_version(key), key)) == 0
1422                              && (unsigned long long)
1423                              GET_GENERATION_NUMBER(le_key_k_offset
1424                                                    (le_key_version(key),
1425                                                     key)) == 1))
1426                                 reiserfs_warning(th->t_super,
1427                                                  "vs-5355: reiserfs_delete_solid_item: %k not found",
1428                                                  key);
1429                         break;
1430                 }
1431                 if (!tb_init) {
1432                         tb_init = 1;
1433                         item_len = ih_item_len(PATH_PITEM_HEAD(&path));
1434                         init_tb_struct(th, &tb, th->t_super, &path,
1435                                        -(IH_SIZE + item_len));
1436                 }
1437                 quota_cut_bytes = ih_item_len(PATH_PITEM_HEAD(&path));
1438
1439                 retval = fix_nodes(M_DELETE, &tb, NULL, NULL);
1440                 if (retval == REPEAT_SEARCH) {
1441                         PROC_INFO_INC(th->t_super, delete_solid_item_restarted);
1442                         continue;
1443                 }
1444
1445                 if (retval == CARRY_ON) {
1446                         do_balance(&tb, NULL, NULL, M_DELETE);
1447                         if (inode) {    /* Should we count quota for item? (we don't count quotas for save-links) */
1448 #ifdef REISERQUOTA_DEBUG
1449                                 reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
1450                                                "reiserquota delete_solid_item(): freeing %u id=%u type=%c",
1451                                                quota_cut_bytes, inode->i_uid,
1452                                                key2type(key));
1453 #endif
1454                                 DQUOT_FREE_SPACE_NODIRTY(inode,
1455                                                          quota_cut_bytes);
1456                         }
1457                         break;
1458                 }
1459                 // IO_ERROR, NO_DISK_SPACE, etc
1460                 reiserfs_warning(th->t_super,
1461                                  "vs-5360: reiserfs_delete_solid_item: "
1462                                  "could not delete %K due to fix_nodes failure",
1463                                  &cpu_key);
1464                 unfix_nodes(&tb);
1465                 break;
1466         }
1467
1468         reiserfs_check_path(&path);
1469 }
1470
1471 int reiserfs_delete_object(struct reiserfs_transaction_handle *th,
1472                            struct inode *inode)
1473 {
1474         int err;
1475         inode->i_size = 0;
1476         BUG_ON(!th->t_trans_id);
1477
1478         /* for directory this deletes item containing "." and ".." */
1479         err =
1480             reiserfs_do_truncate(th, inode, NULL, 0 /*no timestamp updates */ );
1481         if (err)
1482                 return err;
1483
1484 #if defined( USE_INODE_GENERATION_COUNTER )
1485         if (!old_format_only(th->t_super)) {
1486                 __le32 *inode_generation;
1487
1488                 inode_generation =
1489                     &REISERFS_SB(th->t_super)->s_rs->s_inode_generation;
1490                 *inode_generation =
1491                     cpu_to_le32(le32_to_cpu(*inode_generation) + 1);
1492         }
1493 /* USE_INODE_GENERATION_COUNTER */
1494 #endif
1495         reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode));
1496
1497         return err;
1498 }
1499
1500 static void unmap_buffers(struct page *page, loff_t pos)
1501 {
1502         struct buffer_head *bh;
1503         struct buffer_head *head;
1504         struct buffer_head *next;
1505         unsigned long tail_index;
1506         unsigned long cur_index;
1507
1508         if (page) {
1509                 if (page_has_buffers(page)) {
1510                         tail_index = pos & (PAGE_CACHE_SIZE - 1);
1511                         cur_index = 0;
1512                         head = page_buffers(page);
1513                         bh = head;
1514                         do {
1515                                 next = bh->b_this_page;
1516
1517                                 /* we want to unmap the buffers that contain the tail, and
1518                                  ** all the buffers after it (since the tail must be at the
1519                                  ** end of the file).  We don't want to unmap file data
1520                                  ** before the tail, since it might be dirty and waiting to
1521                                  ** reach disk
1522                                  */
1523                                 cur_index += bh->b_size;
1524                                 if (cur_index > tail_index) {
1525                                         reiserfs_unmap_buffer(bh);
1526                                 }
1527                                 bh = next;
1528                         } while (bh != head);
1529                         if (PAGE_SIZE == bh->b_size) {
1530                                 clear_page_dirty(page);
1531                         }
1532                 }
1533         }
1534 }
1535
1536 static int maybe_indirect_to_direct(struct reiserfs_transaction_handle *th,
1537                                     struct inode *p_s_inode,
1538                                     struct page *page,
1539                                     struct path *p_s_path,
1540                                     const struct cpu_key *p_s_item_key,
1541                                     loff_t n_new_file_size, char *p_c_mode)
1542 {
1543         struct super_block *p_s_sb = p_s_inode->i_sb;
1544         int n_block_size = p_s_sb->s_blocksize;
1545         int cut_bytes;
1546         BUG_ON(!th->t_trans_id);
1547
1548         if (n_new_file_size != p_s_inode->i_size)
1549                 BUG();
1550
1551         /* the page being sent in could be NULL if there was an i/o error
1552          ** reading in the last block.  The user will hit problems trying to
1553          ** read the file, but for now we just skip the indirect2direct
1554          */
1555         if (atomic_read(&p_s_inode->i_count) > 1 ||
1556             !tail_has_to_be_packed(p_s_inode) ||
1557             !page || (REISERFS_I(p_s_inode)->i_flags & i_nopack_mask)) {
1558                 // leave tail in an unformatted node
1559                 *p_c_mode = M_SKIP_BALANCING;
1560                 cut_bytes =
1561                     n_block_size - (n_new_file_size & (n_block_size - 1));
1562                 pathrelse(p_s_path);
1563                 return cut_bytes;
1564         }
1565         /* Permorm the conversion to a direct_item. */
1566         /*return indirect_to_direct (p_s_inode, p_s_path, p_s_item_key, n_new_file_size, p_c_mode); */
1567         return indirect2direct(th, p_s_inode, page, p_s_path, p_s_item_key,
1568                                n_new_file_size, p_c_mode);
1569 }
1570
1571 /* we did indirect_to_direct conversion. And we have inserted direct
1572    item successesfully, but there were no disk space to cut unfm
1573    pointer being converted. Therefore we have to delete inserted
1574    direct item(s) */
1575 static void indirect_to_direct_roll_back(struct reiserfs_transaction_handle *th,
1576                                          struct inode *inode, struct path *path)
1577 {
1578         struct cpu_key tail_key;
1579         int tail_len;
1580         int removed;
1581         BUG_ON(!th->t_trans_id);
1582
1583         make_cpu_key(&tail_key, inode, inode->i_size + 1, TYPE_DIRECT, 4);      // !!!!
1584         tail_key.key_length = 4;
1585
1586         tail_len =
1587             (cpu_key_k_offset(&tail_key) & (inode->i_sb->s_blocksize - 1)) - 1;
1588         while (tail_len) {
1589                 /* look for the last byte of the tail */
1590                 if (search_for_position_by_key(inode->i_sb, &tail_key, path) ==
1591                     POSITION_NOT_FOUND)
1592                         reiserfs_panic(inode->i_sb,
1593                                        "vs-5615: indirect_to_direct_roll_back: found invalid item");
1594                 RFALSE(path->pos_in_item !=
1595                        ih_item_len(PATH_PITEM_HEAD(path)) - 1,
1596                        "vs-5616: appended bytes found");
1597                 PATH_LAST_POSITION(path)--;
1598
1599                 removed =
1600                     reiserfs_delete_item(th, path, &tail_key, inode,
1601                                          NULL /*unbh not needed */ );
1602                 RFALSE(removed <= 0
1603                        || removed > tail_len,
1604                        "vs-5617: there was tail %d bytes, removed item length %d bytes",
1605                        tail_len, removed);
1606                 tail_len -= removed;
1607                 set_cpu_key_k_offset(&tail_key,
1608                                      cpu_key_k_offset(&tail_key) - removed);
1609         }
1610         reiserfs_warning(inode->i_sb,
1611                          "indirect_to_direct_roll_back: indirect_to_direct conversion has been rolled back due to lack of disk space");
1612         //mark_file_without_tail (inode);
1613         mark_inode_dirty(inode);
1614 }
1615
1616 /* (Truncate or cut entry) or delete object item. Returns < 0 on failure */
1617 int reiserfs_cut_from_item(struct reiserfs_transaction_handle *th,
1618                            struct path *p_s_path,
1619                            struct cpu_key *p_s_item_key,
1620                            struct inode *p_s_inode,
1621                            struct page *page, loff_t n_new_file_size)
1622 {
1623         struct super_block *p_s_sb = p_s_inode->i_sb;
1624         /* Every function which is going to call do_balance must first
1625            create a tree_balance structure.  Then it must fill up this
1626            structure by using the init_tb_struct and fix_nodes functions.
1627            After that we can make tree balancing. */
1628         struct tree_balance s_cut_balance;
1629         struct item_head *p_le_ih;
1630         int n_cut_size = 0,     /* Amount to be cut. */
1631             n_ret_value = CARRY_ON, n_removed = 0,      /* Number of the removed unformatted nodes. */
1632             n_is_inode_locked = 0;
1633         char c_mode;            /* Mode of the balance. */
1634         int retval2 = -1;
1635         int quota_cut_bytes;
1636         loff_t tail_pos = 0;
1637
1638         BUG_ON(!th->t_trans_id);
1639
1640         init_tb_struct(th, &s_cut_balance, p_s_inode->i_sb, p_s_path,
1641                        n_cut_size);
1642
1643         /* Repeat this loop until we either cut the item without needing
1644            to balance, or we fix_nodes without schedule occurring */
1645         while (1) {
1646                 /* Determine the balance mode, position of the first byte to
1647                    be cut, and size to be cut.  In case of the indirect item
1648                    free unformatted nodes which are pointed to by the cut
1649                    pointers. */
1650
1651                 c_mode =
1652                     prepare_for_delete_or_cut(th, p_s_inode, p_s_path,
1653                                               p_s_item_key, &n_removed,
1654                                               &n_cut_size, n_new_file_size);
1655                 if (c_mode == M_CONVERT) {
1656                         /* convert last unformatted node to direct item or leave
1657                            tail in the unformatted node */
1658                         RFALSE(n_ret_value != CARRY_ON,
1659                                "PAP-5570: can not convert twice");
1660
1661                         n_ret_value =
1662                             maybe_indirect_to_direct(th, p_s_inode, page,
1663                                                      p_s_path, p_s_item_key,
1664                                                      n_new_file_size, &c_mode);
1665                         if (c_mode == M_SKIP_BALANCING)
1666                                 /* tail has been left in the unformatted node */
1667                                 return n_ret_value;
1668
1669                         n_is_inode_locked = 1;
1670
1671                         /* removing of last unformatted node will change value we
1672                            have to return to truncate. Save it */
1673                         retval2 = n_ret_value;
1674                         /*retval2 = p_s_sb->s_blocksize - (n_new_file_size & (p_s_sb->s_blocksize - 1)); */
1675
1676                         /* So, we have performed the first part of the conversion:
1677                            inserting the new direct item.  Now we are removing the
1678                            last unformatted node pointer. Set key to search for
1679                            it. */
1680                         set_cpu_key_k_type(p_s_item_key, TYPE_INDIRECT);
1681                         p_s_item_key->key_length = 4;
1682                         n_new_file_size -=
1683                             (n_new_file_size & (p_s_sb->s_blocksize - 1));
1684                         tail_pos = n_new_file_size;
1685                         set_cpu_key_k_offset(p_s_item_key, n_new_file_size + 1);
1686                         if (search_for_position_by_key
1687                             (p_s_sb, p_s_item_key,
1688                              p_s_path) == POSITION_NOT_FOUND) {
1689                                 print_block(PATH_PLAST_BUFFER(p_s_path), 3,
1690                                             PATH_LAST_POSITION(p_s_path) - 1,
1691                                             PATH_LAST_POSITION(p_s_path) + 1);
1692                                 reiserfs_panic(p_s_sb,
1693                                                "PAP-5580: reiserfs_cut_from_item: item to convert does not exist (%K)",
1694                                                p_s_item_key);
1695                         }
1696                         continue;
1697                 }
1698                 if (n_cut_size == 0) {
1699                         pathrelse(p_s_path);
1700                         return 0;
1701                 }
1702
1703                 s_cut_balance.insert_size[0] = n_cut_size;
1704
1705                 n_ret_value = fix_nodes(c_mode, &s_cut_balance, NULL, NULL);
1706                 if (n_ret_value != REPEAT_SEARCH)
1707                         break;
1708
1709                 PROC_INFO_INC(p_s_sb, cut_from_item_restarted);
1710
1711                 n_ret_value =
1712                     search_for_position_by_key(p_s_sb, p_s_item_key, p_s_path);
1713                 if (n_ret_value == POSITION_FOUND)
1714                         continue;
1715
1716                 reiserfs_warning(p_s_sb,
1717                                  "PAP-5610: reiserfs_cut_from_item: item %K not found",
1718                                  p_s_item_key);
1719                 unfix_nodes(&s_cut_balance);
1720                 return (n_ret_value == IO_ERROR) ? -EIO : -ENOENT;
1721         }                       /* while */
1722
1723         // check fix_nodes results (IO_ERROR or NO_DISK_SPACE)
1724         if (n_ret_value != CARRY_ON) {
1725                 if (n_is_inode_locked) {
1726                         // FIXME: this seems to be not needed: we are always able
1727                         // to cut item
1728                         indirect_to_direct_roll_back(th, p_s_inode, p_s_path);
1729                 }
1730                 if (n_ret_value == NO_DISK_SPACE)
1731                         reiserfs_warning(p_s_sb, "NO_DISK_SPACE");
1732                 unfix_nodes(&s_cut_balance);
1733                 return -EIO;
1734         }
1735
1736         /* go ahead and perform balancing */
1737
1738         RFALSE(c_mode == M_PASTE || c_mode == M_INSERT, "invalid mode");
1739
1740         /* Calculate number of bytes that need to be cut from the item. */
1741         quota_cut_bytes =
1742             (c_mode ==
1743              M_DELETE) ? ih_item_len(get_ih(p_s_path)) : -s_cut_balance.
1744             insert_size[0];
1745         if (retval2 == -1)
1746                 n_ret_value = calc_deleted_bytes_number(&s_cut_balance, c_mode);
1747         else
1748                 n_ret_value = retval2;
1749
1750         /* For direct items, we only change the quota when deleting the last
1751          ** item.
1752          */
1753         p_le_ih = PATH_PITEM_HEAD(s_cut_balance.tb_path);
1754         if (!S_ISLNK(p_s_inode->i_mode) && is_direct_le_ih(p_le_ih)) {
1755                 if (c_mode == M_DELETE &&
1756                     (le_ih_k_offset(p_le_ih) & (p_s_sb->s_blocksize - 1)) ==
1757                     1) {
1758                         // FIXME: this is to keep 3.5 happy
1759                         REISERFS_I(p_s_inode)->i_first_direct_byte = U32_MAX;
1760                         quota_cut_bytes = p_s_sb->s_blocksize + UNFM_P_SIZE;
1761                 } else {
1762                         quota_cut_bytes = 0;
1763                 }
1764         }
1765 #ifdef CONFIG_REISERFS_CHECK
1766         if (n_is_inode_locked) {
1767                 struct item_head *le_ih =
1768                     PATH_PITEM_HEAD(s_cut_balance.tb_path);
1769                 /* we are going to complete indirect2direct conversion. Make
1770                    sure, that we exactly remove last unformatted node pointer
1771                    of the item */
1772                 if (!is_indirect_le_ih(le_ih))
1773                         reiserfs_panic(p_s_sb,
1774                                        "vs-5652: reiserfs_cut_from_item: "
1775                                        "item must be indirect %h", le_ih);
1776
1777                 if (c_mode == M_DELETE && ih_item_len(le_ih) != UNFM_P_SIZE)
1778                         reiserfs_panic(p_s_sb,
1779                                        "vs-5653: reiserfs_cut_from_item: "
1780                                        "completing indirect2direct conversion indirect item %h "
1781                                        "being deleted must be of 4 byte long",
1782                                        le_ih);
1783
1784                 if (c_mode == M_CUT
1785                     && s_cut_balance.insert_size[0] != -UNFM_P_SIZE) {
1786                         reiserfs_panic(p_s_sb,
1787                                        "vs-5654: reiserfs_cut_from_item: "
1788                                        "can not complete indirect2direct conversion of %h (CUT, insert_size==%d)",
1789                                        le_ih, s_cut_balance.insert_size[0]);
1790                 }
1791                 /* it would be useful to make sure, that right neighboring
1792                    item is direct item of this file */
1793         }
1794 #endif
1795
1796         do_balance(&s_cut_balance, NULL, NULL, c_mode);
1797         if (n_is_inode_locked) {
1798                 /* we've done an indirect->direct conversion.  when the data block
1799                  ** was freed, it was removed from the list of blocks that must
1800                  ** be flushed before the transaction commits, make sure to
1801                  ** unmap and invalidate it
1802                  */
1803                 unmap_buffers(page, tail_pos);
1804                 REISERFS_I(p_s_inode)->i_flags &= ~i_pack_on_close_mask;
1805         }
1806 #ifdef REISERQUOTA_DEBUG
1807         reiserfs_debug(p_s_inode->i_sb, REISERFS_DEBUG_CODE,
1808                        "reiserquota cut_from_item(): freeing %u id=%u type=%c",
1809                        quota_cut_bytes, p_s_inode->i_uid, '?');
1810 #endif
1811         DQUOT_FREE_SPACE_NODIRTY(p_s_inode, quota_cut_bytes);
1812         return n_ret_value;
1813 }
1814
1815 static void truncate_directory(struct reiserfs_transaction_handle *th,
1816                                struct inode *inode)
1817 {
1818         BUG_ON(!th->t_trans_id);
1819         if (inode->i_nlink)
1820                 reiserfs_warning(inode->i_sb,
1821                                  "vs-5655: truncate_directory: link count != 0");
1822
1823         set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), DOT_OFFSET);
1824         set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_DIRENTRY);
1825         reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode));
1826         reiserfs_update_sd(th, inode);
1827         set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), SD_OFFSET);
1828         set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_STAT_DATA);
1829 }
1830
1831 /* Truncate file to the new size. Note, this must be called with a transaction
1832    already started */
1833 int reiserfs_do_truncate(struct reiserfs_transaction_handle *th, struct inode *p_s_inode,       /* ->i_size contains new
1834                                                                                                    size */
1835                          struct page *page,     /* up to date for last block */
1836                          int update_timestamps  /* when it is called by
1837                                                    file_release to convert
1838                                                    the tail - no timestamps
1839                                                    should be updated */
1840     )
1841 {
1842         INITIALIZE_PATH(s_search_path); /* Path to the current object item. */
1843         struct item_head *p_le_ih;      /* Pointer to an item header. */
1844         struct cpu_key s_item_key;      /* Key to search for a previous file item. */
1845         loff_t n_file_size,     /* Old file size. */
1846          n_new_file_size;       /* New file size. */
1847         int n_deleted;          /* Number of deleted or truncated bytes. */
1848         int retval;
1849         int err = 0;
1850
1851         BUG_ON(!th->t_trans_id);
1852         if (!
1853             (S_ISREG(p_s_inode->i_mode) || S_ISDIR(p_s_inode->i_mode)
1854              || S_ISLNK(p_s_inode->i_mode)))
1855                 return 0;
1856
1857         if (S_ISDIR(p_s_inode->i_mode)) {
1858                 // deletion of directory - no need to update timestamps
1859                 truncate_directory(th, p_s_inode);
1860                 return 0;
1861         }
1862
1863         /* Get new file size. */
1864         n_new_file_size = p_s_inode->i_size;
1865
1866         // FIXME: note, that key type is unimportant here
1867         make_cpu_key(&s_item_key, p_s_inode, max_reiserfs_offset(p_s_inode),
1868                      TYPE_DIRECT, 3);
1869
1870         retval =
1871             search_for_position_by_key(p_s_inode->i_sb, &s_item_key,
1872                                        &s_search_path);
1873         if (retval == IO_ERROR) {
1874                 reiserfs_warning(p_s_inode->i_sb,
1875                                  "vs-5657: reiserfs_do_truncate: "
1876                                  "i/o failure occurred trying to truncate %K",
1877                                  &s_item_key);
1878                 err = -EIO;
1879                 goto out;
1880         }
1881         if (retval == POSITION_FOUND || retval == FILE_NOT_FOUND) {
1882                 reiserfs_warning(p_s_inode->i_sb,
1883                                  "PAP-5660: reiserfs_do_truncate: "
1884                                  "wrong result %d of search for %K", retval,
1885                                  &s_item_key);
1886
1887                 err = -EIO;
1888                 goto out;
1889         }
1890
1891         s_search_path.pos_in_item--;
1892
1893         /* Get real file size (total length of all file items) */
1894         p_le_ih = PATH_PITEM_HEAD(&s_search_path);
1895         if (is_statdata_le_ih(p_le_ih))
1896                 n_file_size = 0;
1897         else {
1898                 loff_t offset = le_ih_k_offset(p_le_ih);
1899                 int bytes =
1900                     op_bytes_number(p_le_ih, p_s_inode->i_sb->s_blocksize);
1901
1902                 /* this may mismatch with real file size: if last direct item
1903                    had no padding zeros and last unformatted node had no free
1904                    space, this file would have this file size */
1905                 n_file_size = offset + bytes - 1;
1906         }
1907         /*
1908          * are we doing a full truncate or delete, if so
1909          * kick in the reada code
1910          */
1911         if (n_new_file_size == 0)
1912                 s_search_path.reada = PATH_READA | PATH_READA_BACK;
1913
1914         if (n_file_size == 0 || n_file_size < n_new_file_size) {
1915                 goto update_and_out;
1916         }
1917
1918         /* Update key to search for the last file item. */
1919         set_cpu_key_k_offset(&s_item_key, n_file_size);
1920
1921         do {
1922                 /* Cut or delete file item. */
1923                 n_deleted =
1924                     reiserfs_cut_from_item(th, &s_search_path, &s_item_key,
1925                                            p_s_inode, page, n_new_file_size);
1926                 if (n_deleted < 0) {
1927                         reiserfs_warning(p_s_inode->i_sb,
1928                                          "vs-5665: reiserfs_do_truncate: reiserfs_cut_from_item failed");
1929                         reiserfs_check_path(&s_search_path);
1930                         return 0;
1931                 }
1932
1933                 RFALSE(n_deleted > n_file_size,
1934                        "PAP-5670: reiserfs_cut_from_item: too many bytes deleted: deleted %d, file_size %lu, item_key %K",
1935                        n_deleted, n_file_size, &s_item_key);
1936
1937                 /* Change key to search the last file item. */
1938                 n_file_size -= n_deleted;
1939
1940                 set_cpu_key_k_offset(&s_item_key, n_file_size);
1941
1942                 /* While there are bytes to truncate and previous file item is presented in the tree. */
1943
1944                 /*
1945                  ** This loop could take a really long time, and could log
1946                  ** many more blocks than a transaction can hold.  So, we do a polite
1947                  ** journal end here, and if the transaction needs ending, we make
1948                  ** sure the file is consistent before ending the current trans
1949                  ** and starting a new one
1950                  */
1951                 if (journal_transaction_should_end(th, th->t_blocks_allocated)) {
1952                         int orig_len_alloc = th->t_blocks_allocated;
1953                         decrement_counters_in_path(&s_search_path);
1954
1955                         if (update_timestamps) {
1956                                 p_s_inode->i_mtime = p_s_inode->i_ctime =
1957                                     CURRENT_TIME_SEC;
1958                         }
1959                         reiserfs_update_sd(th, p_s_inode);
1960
1961                         err = journal_end(th, p_s_inode->i_sb, orig_len_alloc);
1962                         if (err)
1963                                 goto out;
1964                         err = journal_begin(th, p_s_inode->i_sb,
1965                                             JOURNAL_PER_BALANCE_CNT * 6);
1966                         if (err)
1967                                 goto out;
1968                         reiserfs_update_inode_transaction(p_s_inode);
1969                 }
1970         } while (n_file_size > ROUND_UP(n_new_file_size) &&
1971                  search_for_position_by_key(p_s_inode->i_sb, &s_item_key,
1972                                             &s_search_path) == POSITION_FOUND);
1973
1974         RFALSE(n_file_size > ROUND_UP(n_new_file_size),
1975                "PAP-5680: truncate did not finish: new_file_size %Ld, current %Ld, oid %d",
1976                n_new_file_size, n_file_size, s_item_key.on_disk_key.k_objectid);
1977
1978       update_and_out:
1979         if (update_timestamps) {
1980                 // this is truncate, not file closing
1981                 p_s_inode->i_mtime = p_s_inode->i_ctime = CURRENT_TIME_SEC;
1982         }
1983         reiserfs_update_sd(th, p_s_inode);
1984
1985       out:
1986         pathrelse(&s_search_path);
1987         return err;
1988 }
1989
1990 #ifdef CONFIG_REISERFS_CHECK
1991 // this makes sure, that we __append__, not overwrite or add holes
1992 static void check_research_for_paste(struct path *path,
1993                                      const struct cpu_key *p_s_key)
1994 {
1995         struct item_head *found_ih = get_ih(path);
1996
1997         if (is_direct_le_ih(found_ih)) {
1998                 if (le_ih_k_offset(found_ih) +
1999                     op_bytes_number(found_ih,
2000                                     get_last_bh(path)->b_size) !=
2001                     cpu_key_k_offset(p_s_key)
2002                     || op_bytes_number(found_ih,
2003                                        get_last_bh(path)->b_size) !=
2004                     pos_in_item(path))
2005                         reiserfs_panic(NULL,
2006                                        "PAP-5720: check_research_for_paste: "
2007                                        "found direct item %h or position (%d) does not match to key %K",
2008                                        found_ih, pos_in_item(path), p_s_key);
2009         }
2010         if (is_indirect_le_ih(found_ih)) {
2011                 if (le_ih_k_offset(found_ih) +
2012                     op_bytes_number(found_ih,
2013                                     get_last_bh(path)->b_size) !=
2014                     cpu_key_k_offset(p_s_key)
2015                     || I_UNFM_NUM(found_ih) != pos_in_item(path)
2016                     || get_ih_free_space(found_ih) != 0)
2017                         reiserfs_panic(NULL,
2018                                        "PAP-5730: check_research_for_paste: "
2019                                        "found indirect item (%h) or position (%d) does not match to key (%K)",
2020                                        found_ih, pos_in_item(path), p_s_key);
2021         }
2022 }
2023 #endif                          /* config reiserfs check */
2024
2025 /* Paste bytes to the existing item. Returns bytes number pasted into the item. */
2026 int reiserfs_paste_into_item(struct reiserfs_transaction_handle *th, struct path *p_s_search_path,      /* Path to the pasted item.          */
2027                              const struct cpu_key *p_s_key,     /* Key to search for the needed item. */
2028                              struct inode *inode,       /* Inode item belongs to */
2029                              const char *p_c_body,      /* Pointer to the bytes to paste.    */
2030                              int n_pasted_size)
2031 {                               /* Size of pasted bytes.             */
2032         struct tree_balance s_paste_balance;
2033         int retval;
2034         int fs_gen;
2035
2036         BUG_ON(!th->t_trans_id);
2037
2038         fs_gen = get_generation(inode->i_sb);
2039
2040 #ifdef REISERQUOTA_DEBUG
2041         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
2042                        "reiserquota paste_into_item(): allocating %u id=%u type=%c",
2043                        n_pasted_size, inode->i_uid,
2044                        key2type(&(p_s_key->on_disk_key)));
2045 #endif
2046
2047         if (DQUOT_ALLOC_SPACE_NODIRTY(inode, n_pasted_size)) {
2048                 pathrelse(p_s_search_path);
2049                 return -EDQUOT;
2050         }
2051         init_tb_struct(th, &s_paste_balance, th->t_super, p_s_search_path,
2052                        n_pasted_size);
2053 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
2054         s_paste_balance.key = p_s_key->on_disk_key;
2055 #endif
2056
2057         /* DQUOT_* can schedule, must check before the fix_nodes */
2058         if (fs_changed(fs_gen, inode->i_sb)) {
2059                 goto search_again;
2060         }
2061
2062         while ((retval =
2063                 fix_nodes(M_PASTE, &s_paste_balance, NULL,
2064                           p_c_body)) == REPEAT_SEARCH) {
2065               search_again:
2066                 /* file system changed while we were in the fix_nodes */
2067                 PROC_INFO_INC(th->t_super, paste_into_item_restarted);
2068                 retval =
2069                     search_for_position_by_key(th->t_super, p_s_key,
2070                                                p_s_search_path);
2071                 if (retval == IO_ERROR) {
2072                         retval = -EIO;
2073                         goto error_out;
2074                 }
2075                 if (retval == POSITION_FOUND) {
2076                         reiserfs_warning(inode->i_sb,
2077                                          "PAP-5710: reiserfs_paste_into_item: entry or pasted byte (%K) exists",
2078                                          p_s_key);
2079                         retval = -EEXIST;
2080                         goto error_out;
2081                 }
2082 #ifdef CONFIG_REISERFS_CHECK
2083                 check_research_for_paste(p_s_search_path, p_s_key);
2084 #endif
2085         }
2086
2087         /* Perform balancing after all resources are collected by fix_nodes, and
2088            accessing them will not risk triggering schedule. */
2089         if (retval == CARRY_ON) {
2090                 do_balance(&s_paste_balance, NULL /*ih */ , p_c_body, M_PASTE);
2091                 return 0;
2092         }
2093         retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
2094       error_out:
2095         /* this also releases the path */
2096         unfix_nodes(&s_paste_balance);
2097 #ifdef REISERQUOTA_DEBUG
2098         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
2099                        "reiserquota paste_into_item(): freeing %u id=%u type=%c",
2100                        n_pasted_size, inode->i_uid,
2101                        key2type(&(p_s_key->on_disk_key)));
2102 #endif
2103         DQUOT_FREE_SPACE_NODIRTY(inode, n_pasted_size);
2104         return retval;
2105 }
2106
2107 /* Insert new item into the buffer at the path. */
2108 int reiserfs_insert_item(struct reiserfs_transaction_handle *th, struct path *p_s_path, /* Path to the inserteded item.         */
2109                          const struct cpu_key *key, struct item_head *p_s_ih,   /* Pointer to the item header to insert. */
2110                          struct inode *inode, const char *p_c_body)
2111 {                               /* Pointer to the bytes to insert.      */
2112         struct tree_balance s_ins_balance;
2113         int retval;
2114         int fs_gen = 0;
2115         int quota_bytes = 0;
2116
2117         BUG_ON(!th->t_trans_id);
2118
2119         if (inode) {            /* Do we count quotas for item? */
2120                 fs_gen = get_generation(inode->i_sb);
2121                 quota_bytes = ih_item_len(p_s_ih);
2122
2123                 /* hack so the quota code doesn't have to guess if the file has
2124                  ** a tail, links are always tails, so there's no guessing needed
2125                  */
2126                 if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(p_s_ih)) {
2127                         quota_bytes = inode->i_sb->s_blocksize + UNFM_P_SIZE;
2128                 }
2129 #ifdef REISERQUOTA_DEBUG
2130                 reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
2131                                "reiserquota insert_item(): allocating %u id=%u type=%c",
2132                                quota_bytes, inode->i_uid, head2type(p_s_ih));
2133 #endif
2134                 /* We can't dirty inode here. It would be immediately written but
2135                  * appropriate stat item isn't inserted yet... */
2136                 if (DQUOT_ALLOC_SPACE_NODIRTY(inode, quota_bytes)) {
2137                         pathrelse(p_s_path);
2138                         return -EDQUOT;
2139                 }
2140         }
2141         init_tb_struct(th, &s_ins_balance, th->t_super, p_s_path,
2142                        IH_SIZE + ih_item_len(p_s_ih));
2143 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
2144         s_ins_balance.key = key->on_disk_key;
2145 #endif
2146         /* DQUOT_* can schedule, must check to be sure calling fix_nodes is safe */
2147         if (inode && fs_changed(fs_gen, inode->i_sb)) {
2148                 goto search_again;
2149         }
2150
2151         while ((retval =
2152                 fix_nodes(M_INSERT, &s_ins_balance, p_s_ih,
2153                           p_c_body)) == REPEAT_SEARCH) {
2154               search_again:
2155                 /* file system changed while we were in the fix_nodes */
2156                 PROC_INFO_INC(th->t_super, insert_item_restarted);
2157                 retval = search_item(th->t_super, key, p_s_path);
2158                 if (retval == IO_ERROR) {
2159                         retval = -EIO;
2160                         goto error_out;
2161                 }
2162                 if (retval == ITEM_FOUND) {
2163                         reiserfs_warning(th->t_super,
2164                                          "PAP-5760: reiserfs_insert_item: "
2165                                          "key %K already exists in the tree",
2166                                          key);
2167                         retval = -EEXIST;
2168                         goto error_out;
2169                 }
2170         }
2171
2172         /* make balancing after all resources will be collected at a time */
2173         if (retval == CARRY_ON) {
2174                 do_balance(&s_ins_balance, p_s_ih, p_c_body, M_INSERT);
2175                 return 0;
2176         }
2177
2178         retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
2179       error_out:
2180         /* also releases the path */
2181         unfix_nodes(&s_ins_balance);
2182 #ifdef REISERQUOTA_DEBUG
2183         reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
2184                        "reiserquota insert_item(): freeing %u id=%u type=%c",
2185                        quota_bytes, inode->i_uid, head2type(p_s_ih));
2186 #endif
2187         if (inode)
2188                 DQUOT_FREE_SPACE_NODIRTY(inode, quota_bytes);
2189         return retval;
2190 }