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