fs/reiser4/plugin/item/item.c

   1 /* Copyright 2001, 2002, 2003 by Hans Reiser, licensing governed by reiser4/README */
   2
   3 /* definition of item plugins. */
   4
   5 #include "../../forward.h"
   6 #include "../../debug.h"
   7 #include "../../key.h"
   8 #include "../../coord.h"
   9 #include "../plugin_header.h"
  10 #include "sde.h"
  11 #include "internal.h"
  12 #include "item.h"
  13 #include "static_stat.h"
  14 #include "../plugin.h"
  15 #include "../../znode.h"
  16 #include "../../tree.h"
  17 #include "../../context.h"
  18 #include "ctail.h"
  19
  20 /* return pointer to item body */
  21 void item_body_by_coord_hard(coord_t * coord /* coord to query */ )
  22 {
  23         assert("nikita-324", coord != NULL);
  24         assert("nikita-325", coord->node != NULL);
  25         assert("nikita-326", znode_is_loaded(coord->node));
  26         assert("nikita-3200", coord->offset == INVALID_OFFSET);
  27
  28         coord->offset =
  29             node_plugin_by_node(coord->node)->item_by_coord(coord) -
  30             zdata(coord->node);
  31         ON_DEBUG(coord->body_v = coord->node->times_locked);
  32 }
  33
  34 void *item_body_by_coord_easy(const coord_t * coord /* coord to query */ )
  35 {
  36         return zdata(coord->node) + coord->offset;
  37 }
  38
  39 #if REISER4_DEBUG
  40
  41 int item_body_is_valid(const coord_t * coord)
  42 {
  43         return
  44             coord->offset ==
  45             node_plugin_by_node(coord->node)->item_by_coord(coord) -
  46             zdata(coord->node);
  47 }
  48
  49 #endif
  50
  51 /* return length of item at @coord */
  52 pos_in_node_t item_length_by_coord(const coord_t * coord /* coord to query */ )
  53 {
  54         int len;
  55
  56         assert("nikita-327", coord != NULL);
  57         assert("nikita-328", coord->node != NULL);
  58         assert("nikita-329", znode_is_loaded(coord->node));
  59
  60         len = node_plugin_by_node(coord->node)->length_by_coord(coord);
  61         return len;
  62 }
  63
  64 void obtain_item_plugin(const coord_t * coord)
  65 {
  66         assert("nikita-330", coord != NULL);
  67         assert("nikita-331", coord->node != NULL);
  68         assert("nikita-332", znode_is_loaded(coord->node));
  69
  70         coord_set_iplug((coord_t *) coord,
  71                         node_plugin_by_node(coord->node)->
  72                         plugin_by_coord(coord));
  73         assert("nikita-2479",
  74                coord_iplug(coord) ==
  75                node_plugin_by_node(coord->node)->plugin_by_coord(coord));
  76 }
  77
  78 /* return id of item */
  79 /* Audited by: green(2002.06.15) */
  80 item_id item_id_by_coord(const coord_t * coord /* coord to query */ )
  81 {
  82         assert("vs-539", coord != NULL);
  83         assert("vs-538", coord->node != NULL);
  84         assert("vs-537", znode_is_loaded(coord->node));
  85         assert("vs-536", item_plugin_by_coord(coord) != NULL);
  86         assert("vs-540",
  87                item_id_by_plugin(item_plugin_by_coord(coord)) < LAST_ITEM_ID);
  88
  89         return item_id_by_plugin(item_plugin_by_coord(coord));
  90 }
  91
  92 /* return key of item at @coord */
  93 /* Audited by: green(2002.06.15) */
  94 reiser4_key *item_key_by_coord(const coord_t * coord /* coord to query */ ,
  95                                reiser4_key * key /* result */ )
  96 {
  97         assert("nikita-338", coord != NULL);
  98         assert("nikita-339", coord->node != NULL);
  99         assert("nikita-340", znode_is_loaded(coord->node));
 100
 101         return node_plugin_by_node(coord->node)->key_at(coord, key);
 102 }
 103
 104 /* this returns max key in the item */
 105 reiser4_key *max_item_key_by_coord(const coord_t * coord /* coord to query */ ,
 106                                    reiser4_key * key /* result */ )
 107 {
 108         coord_t last;
 109
 110         assert("nikita-338", coord != NULL);
 111         assert("nikita-339", coord->node != NULL);
 112         assert("nikita-340", znode_is_loaded(coord->node));
 113
 114         /* make coord pointing to last item's unit */
 115         coord_dup(&last, coord);
 116         last.unit_pos = coord_num_units(&last) - 1;
 117         assert("vs-1560", coord_is_existing_unit(&last));
 118
 119         max_unit_key_by_coord(&last, key);
 120         return key;
 121 }
 122
 123 /* return key of unit at @coord */
 124 reiser4_key *unit_key_by_coord(const coord_t * coord /* coord to query */ ,
 125                                reiser4_key * key /* result */ )
 126 {
 127         assert("nikita-772", coord != NULL);
 128         assert("nikita-774", coord->node != NULL);
 129         assert("nikita-775", znode_is_loaded(coord->node));
 130
 131         if (item_plugin_by_coord(coord)->b.unit_key != NULL)
 132                 return item_plugin_by_coord(coord)->b.unit_key(coord, key);
 133         else
 134                 return item_key_by_coord(coord, key);
 135 }
 136
 137 /* return the biggest key contained the unit @coord */
 138 reiser4_key *max_unit_key_by_coord(const coord_t * coord /* coord to query */ ,
 139                                    reiser4_key * key /* result */ )
 140 {
 141         assert("nikita-772", coord != NULL);
 142         assert("nikita-774", coord->node != NULL);
 143         assert("nikita-775", znode_is_loaded(coord->node));
 144
 145         if (item_plugin_by_coord(coord)->b.max_unit_key != NULL)
 146                 return item_plugin_by_coord(coord)->b.max_unit_key(coord, key);
 147         else
 148                 return unit_key_by_coord(coord, key);
 149 }
 150
 151 /* ->max_key_inside() method for items consisting of exactly one key (like
 152     stat-data) */
 153 static reiser4_key *max_key_inside_single_key(const coord_t *
 154                                               coord /* coord of item */ ,
 155                                               reiser4_key *
 156                                               result /* resulting key */ )
 157 {
 158         assert("nikita-604", coord != NULL);
 159
 160         /* coord -> key is starting key of this item and it has to be already
 161            filled in */
 162         return unit_key_by_coord(coord, result);
 163 }
 164
 165 /* ->nr_units() method for items consisting of exactly one unit always */
 166 pos_in_node_t
 167 nr_units_single_unit(const coord_t * coord UNUSED_ARG /* coord of item */ )
 168 {
 169         return 1;
 170 }
 171
 172 static int
 173 paste_no_paste(coord_t * coord UNUSED_ARG,
 174                reiser4_item_data * data UNUSED_ARG,
 175                carry_plugin_info * info UNUSED_ARG)
 176 {
 177         return 0;
 178 }
 179
 180 /* default ->fast_paste() method */
 181 static int
 182 agree_to_fast_op(const coord_t * coord UNUSED_ARG /* coord of item */ )
 183 {
 184         return 1;
 185 }
 186
 187 int item_can_contain_key(const coord_t * item /* coord of item */ ,
 188                          const reiser4_key * key /* key to check */ ,
 189                          const reiser4_item_data * data /* parameters of item
 190                                                          * being created */ )
 191 {
 192         item_plugin *iplug;
 193         reiser4_key min_key_in_item;
 194         reiser4_key max_key_in_item;
 195
 196         assert("nikita-1658", item != NULL);
 197         assert("nikita-1659", key != NULL);
 198
 199         iplug = item_plugin_by_coord(item);
 200         if (iplug->b.can_contain_key != NULL)
 201                 return iplug->b.can_contain_key(item, key, data);
 202         else {
 203                 assert("nikita-1681", iplug->b.max_key_inside != NULL);
 204                 item_key_by_coord(item, &min_key_in_item);
 205                 iplug->b.max_key_inside(item, &max_key_in_item);
 206
 207                 /* can contain key if
 208                    min_key_in_item <= key &&
 209                    key <= max_key_in_item
 210                  */
 211                 return keyle(&min_key_in_item, key)
 212                     && keyle(key, &max_key_in_item);
 213         }
 214 }
 215
 216 /* mergeable method for non mergeable items */
 217 static int
 218 not_mergeable(const coord_t * i1 UNUSED_ARG, const coord_t * i2 UNUSED_ARG)
 219 {
 220         return 0;
 221 }
 222
 223 /* return 0 if @item1 and @item2 are not mergeable, !0 - otherwise */
 224 int are_items_mergeable(const coord_t * i1 /* coord of first item */ ,
 225                         const coord_t * i2 /* coord of second item */ )
 226 {
 227         item_plugin *iplug;
 228         reiser4_key k1;
 229         reiser4_key k2;
 230
 231         assert("nikita-1336", i1 != NULL);
 232         assert("nikita-1337", i2 != NULL);
 233
 234         iplug = item_plugin_by_coord(i1);
 235         assert("nikita-1338", iplug != NULL);
 236
 237         /* NOTE-NIKITA are_items_mergeable() is also called by assertions in
 238            shifting code when nodes are in "suspended" state. */
 239         assert("nikita-1663",
 240                keyle(item_key_by_coord(i1, &k1), item_key_by_coord(i2, &k2)));
 241
 242         if (iplug->b.mergeable != NULL) {
 243                 return iplug->b.mergeable(i1, i2);
 244         } else if (iplug->b.max_key_inside != NULL) {
 245                 iplug->b.max_key_inside(i1, &k1);
 246                 item_key_by_coord(i2, &k2);
 247
 248                 /* mergeable if ->max_key_inside() >= key of i2; */
 249                 return keyge(iplug->b.max_key_inside(i1, &k1),
 250                              item_key_by_coord(i2, &k2));
 251         } else {
 252                 item_key_by_coord(i1, &k1);
 253                 item_key_by_coord(i2, &k2);
 254
 255                 return
 256                     (get_key_locality(&k1) == get_key_locality(&k2)) &&
 257                     (get_key_objectid(&k1) == get_key_objectid(&k2))
 258                     && (iplug == item_plugin_by_coord(i2));
 259         }
 260 }
 261
 262 int item_is_extent(const coord_t * item)
 263 {
 264         assert("vs-482", coord_is_existing_item(item));
 265         return item_id_by_coord(item) == EXTENT_POINTER_ID;
 266 }
 267
 268 int item_is_tail(const coord_t * item)
 269 {
 270         assert("vs-482", coord_is_existing_item(item));
 271         return item_id_by_coord(item) == FORMATTING_ID;
 272 }
 273
 274 #if REISER4_DEBUG
 275
 276 int item_is_statdata(const coord_t * item)
 277 {
 278         assert("vs-516", coord_is_existing_item(item));
 279         return plugin_of_group(item_plugin_by_coord(item), STAT_DATA_ITEM_TYPE);
 280 }
 281
 282 int item_is_ctail(const coord_t * item)
 283 {
 284         assert("edward-xx", coord_is_existing_item(item));
 285         return item_id_by_coord(item) == CTAIL_ID;
 286 }
 287
 288 #endif  /*  REISER4_DEBUG  */
 289
 290 static int change_item(struct inode *inode,
 291                        reiser4_plugin * plugin,
 292                        pset_member memb)
 293 {
 294         /* cannot change constituent item (sd, or dir_item) */
 295         return RETERR(-EINVAL);
 296 }
 297
 298 static reiser4_plugin_ops item_plugin_ops = {
 299         .init = NULL,
 300         .load = NULL,
 301         .save_len = NULL,
 302         .save = NULL,
 303         .change = change_item
 304 };
 305
 306 item_plugin item_plugins[LAST_ITEM_ID] = {
 307         [STATIC_STAT_DATA_ID] = {
 308                 .h = {
 309                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 310                         .id = STATIC_STAT_DATA_ID,
 311                         .groups = (1 << STAT_DATA_ITEM_TYPE),
 312                         .pops = &item_plugin_ops,
 313                         .label = "sd",
 314                         .desc = "stat-data",
 315                         .linkage = {NULL, NULL}
 316                 },
 317                 .b = {
 318                         .max_key_inside = max_key_inside_single_key,
 319                         .can_contain_key = NULL,
 320                         .mergeable = not_mergeable,
 321                         .nr_units = nr_units_single_unit,
 322                         .lookup = NULL,
 323                         .init = NULL,
 324                         .paste = paste_no_paste,
 325                         .fast_paste = NULL,
 326                         .can_shift = NULL,
 327                         .copy_units = NULL,
 328                         .create_hook = NULL,
 329                         .kill_hook = NULL,
 330                         .shift_hook = NULL,
 331                         .cut_units = NULL,
 332                         .kill_units = NULL,
 333                         .unit_key = NULL,
 334                         .max_unit_key = NULL,
 335                         .estimate = NULL,
 336                         .item_data_by_flow = NULL,
 337 #if REISER4_DEBUG
 338                         .check = NULL
 339 #endif
 340                 },
 341                 .f = {
 342                         .utmost_child = NULL,
 343                         .utmost_child_real_block = NULL,
 344                         .update = NULL,
 345                         .scan = NULL,
 346                         .convert = NULL
 347                 },
 348                 .s = {
 349                         .sd = {
 350                                 .init_inode = init_inode_static_sd,
 351                                 .save_len = save_len_static_sd,
 352                                 .save = save_static_sd
 353                         }
 354                 }
 355         },
 356         [SIMPLE_DIR_ENTRY_ID] = {
 357                 .h = {
 358                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 359                         .id = SIMPLE_DIR_ENTRY_ID,
 360                         .groups = (1 << DIR_ENTRY_ITEM_TYPE),
 361                         .pops = &item_plugin_ops,
 362                         .label = "de",
 363                         .desc = "directory entry",
 364                         .linkage = {NULL, NULL}
 365                 },
 366                 .b = {
 367                         .max_key_inside = max_key_inside_single_key,
 368                         .can_contain_key = NULL,
 369                         .mergeable = NULL,
 370                         .nr_units = nr_units_single_unit,
 371                         .lookup = NULL,
 372                         .init = NULL,
 373                         .paste = NULL,
 374                         .fast_paste = NULL,
 375                         .can_shift = NULL,
 376                         .copy_units = NULL,
 377                         .create_hook = NULL,
 378                         .kill_hook = NULL,
 379                         .shift_hook = NULL,
 380                         .cut_units = NULL,
 381                         .kill_units = NULL,
 382                         .unit_key = NULL,
 383                         .max_unit_key = NULL,
 384                         .estimate = NULL,
 385                         .item_data_by_flow = NULL,
 386 #if REISER4_DEBUG
 387                         .check = NULL
 388 #endif
 389                 },
 390                 .f = {
 391                         .utmost_child = NULL,
 392                         .utmost_child_real_block = NULL,
 393                         .update = NULL,
 394                         .scan = NULL,
 395                         .convert = NULL
 396                 },
 397                 .s = {
 398                         .dir = {
 399                                 .extract_key = extract_key_de,
 400                                 .update_key = update_key_de,
 401                                 .extract_name = extract_name_de,
 402                                 .extract_file_type = extract_file_type_de,
 403                                 .add_entry = add_entry_de,
 404                                 .rem_entry = rem_entry_de,
 405                                 .max_name_len = max_name_len_de
 406                         }
 407                 }
 408         },
 409         [COMPOUND_DIR_ID] = {
 410                 .h = {
 411                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 412                         .id = COMPOUND_DIR_ID,
 413                         .groups = (1 << DIR_ENTRY_ITEM_TYPE),
 414                         .pops = &item_plugin_ops,
 415                         .label = "cde",
 416                         .desc = "compressed directory entry",
 417                         .linkage = {NULL, NULL}
 418                 },
 419                 .b = {
 420                         .max_key_inside = max_key_inside_cde,
 421                         .can_contain_key = can_contain_key_cde,
 422                         .mergeable = mergeable_cde,
 423                         .nr_units = nr_units_cde,
 424                         .lookup = lookup_cde,
 425                         .init = init_cde,
 426                         .paste = paste_cde,
 427                         .fast_paste = agree_to_fast_op,
 428                         .can_shift = can_shift_cde,
 429                         .copy_units = copy_units_cde,
 430                         .create_hook = NULL,
 431                         .kill_hook = NULL,
 432                         .shift_hook = NULL,
 433                         .cut_units = cut_units_cde,
 434                         .kill_units = kill_units_cde,
 435                         .unit_key = unit_key_cde,
 436                         .max_unit_key = unit_key_cde,
 437                         .estimate = estimate_cde,
 438                         .item_data_by_flow = NULL,
 439 #if REISER4_DEBUG
 440                         .check = reiser4_check_cde
 441 #endif
 442                 },
 443                 .f = {
 444                         .utmost_child = NULL,
 445                         .utmost_child_real_block = NULL,
 446                         .update = NULL,
 447                         .scan = NULL,
 448                         .convert = NULL
 449                 },
 450                 .s = {
 451                         .dir = {
 452                                 .extract_key = extract_key_cde,
 453                                 .update_key = update_key_cde,
 454                                 .extract_name = extract_name_cde,
 455                                 .extract_file_type = extract_file_type_de,
 456                                 .add_entry = add_entry_cde,
 457                                 .rem_entry = rem_entry_cde,
 458                                 .max_name_len = max_name_len_cde
 459                         }
 460                 }
 461         },
 462         [NODE_POINTER_ID] = {
 463                 .h = {
 464                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 465                         .id = NODE_POINTER_ID,
 466                         .groups = (1 << INTERNAL_ITEM_TYPE),
 467                         .pops = NULL,
 468                         .label = "internal",
 469                         .desc = "internal item",
 470                         .linkage = {NULL, NULL}
 471                 },
 472                 .b = {
 473                         .max_key_inside = NULL,
 474                         .can_contain_key = NULL,
 475                         .mergeable = mergeable_internal,
 476                         .nr_units = nr_units_single_unit,
 477                         .lookup = lookup_internal,
 478                         .init = NULL,
 479                         .paste = NULL,
 480                         .fast_paste = NULL,
 481                         .can_shift = NULL,
 482                         .copy_units = NULL,
 483                         .create_hook = create_hook_internal,
 484                         .kill_hook = kill_hook_internal,
 485                         .shift_hook = shift_hook_internal,
 486                         .cut_units = NULL,
 487                         .kill_units = NULL,
 488                         .unit_key = NULL,
 489                         .max_unit_key = NULL,
 490                         .estimate = NULL,
 491                         .item_data_by_flow = NULL,
 492 #if REISER4_DEBUG
 493                         .check = check__internal
 494 #endif
 495                 },
 496                 .f = {
 497                         .utmost_child = utmost_child_internal,
 498                         .utmost_child_real_block =
 499                         utmost_child_real_block_internal,
 500                         .update = reiser4_update_internal,
 501                         .scan = NULL,
 502                         .convert = NULL
 503                 },
 504                 .s = {
 505                         .internal = {
 506                                 .down_link = down_link_internal,
 507                                 .has_pointer_to = has_pointer_to_internal
 508                         }
 509                 }
 510         },
 511         [EXTENT_POINTER_ID] = {
 512                 .h = {
 513                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 514                         .id = EXTENT_POINTER_ID,
 515                         .groups = (1 << UNIX_FILE_METADATA_ITEM_TYPE),
 516                         .pops = NULL,
 517                         .label = "extent",
 518                         .desc = "extent item",
 519                         .linkage = {NULL, NULL}
 520                 },
 521                 .b = {
 522                         .max_key_inside = max_key_inside_extent,
 523                         .can_contain_key = can_contain_key_extent,
 524                         .mergeable = mergeable_extent,
 525                         .nr_units = nr_units_extent,
 526                         .lookup = lookup_extent,
 527                         .init = NULL,
 528                         .paste = paste_extent,
 529                         .fast_paste = agree_to_fast_op,
 530                         .can_shift = can_shift_extent,
 531                         .create_hook = create_hook_extent,
 532                         .copy_units = copy_units_extent,
 533                         .kill_hook = kill_hook_extent,
 534                         .shift_hook = NULL,
 535                         .cut_units = cut_units_extent,
 536                         .kill_units = kill_units_extent,
 537                         .unit_key = unit_key_extent,
 538                         .max_unit_key = max_unit_key_extent,
 539                         .estimate = NULL,
 540                         .item_data_by_flow = NULL,
 541 #if REISER4_DEBUG
 542                         .check = reiser4_check_extent
 543 #endif
 544                 },
 545                 .f = {
 546                         .utmost_child = utmost_child_extent,
 547                         .utmost_child_real_block =
 548                         utmost_child_real_block_extent,
 549                         .update = NULL,
 550                         .scan = reiser4_scan_extent,
 551                         .convert = NULL,
 552                         .key_by_offset = key_by_offset_extent
 553                 },
 554                 .s = {
 555                         .file = {
 556                                 .write = reiser4_write_extent,
 557                                 .read = reiser4_read_extent,
 558                                 .readpage = reiser4_readpage_extent,
 559                                 .get_block = get_block_address_extent,
 560                                 .append_key = append_key_extent,
 561                                 .init_coord_extension =
 562                                 init_coord_extension_extent
 563                         }
 564                 }
 565         },
 566         [FORMATTING_ID] = {
 567                 .h = {
 568                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 569                         .id = FORMATTING_ID,
 570                         .groups = (1 << UNIX_FILE_METADATA_ITEM_TYPE),
 571                         .pops = NULL,
 572                         .label = "body",
 573                         .desc = "body (or tail?) item",
 574                         .linkage = {NULL, NULL}
 575                 },
 576                 .b = {
 577                         .max_key_inside = max_key_inside_tail,
 578                         .can_contain_key = can_contain_key_tail,
 579                         .mergeable = mergeable_tail,
 580                         .nr_units = nr_units_tail,
 581                         .lookup = lookup_tail,
 582                         .init = NULL,
 583                         .paste = paste_tail,
 584                         .fast_paste = agree_to_fast_op,
 585                         .can_shift = can_shift_tail,
 586                         .create_hook = NULL,
 587                         .copy_units = copy_units_tail,
 588                         .kill_hook = kill_hook_tail,
 589                         .shift_hook = NULL,
 590                         .cut_units = cut_units_tail,
 591                         .kill_units = kill_units_tail,
 592                         .unit_key = unit_key_tail,
 593                         .max_unit_key = unit_key_tail,
 594                         .estimate = NULL,
 595                         .item_data_by_flow = NULL,
 596 #if REISER4_DEBUG
 597                         .check = NULL
 598 #endif
 599                 },
 600                 .f = {
 601                         .utmost_child = NULL,
 602                         .utmost_child_real_block = NULL,
 603                         .update = NULL,
 604                         .scan = NULL,
 605                         .convert = NULL
 606                 },
 607                 .s = {
 608                         .file = {
 609                                 .write = reiser4_write_tail,
 610                                 .read = reiser4_read_tail,
 611                                 .readpage = readpage_tail,
 612                                 .get_block = get_block_address_tail,
 613                                 .append_key = append_key_tail,
 614                                 .init_coord_extension =
 615                                 init_coord_extension_tail
 616                         }
 617                 }
 618         },
 619         [CTAIL_ID] = {
 620                 .h = {
 621                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 622                         .id = CTAIL_ID,
 623                         .groups = (1 << UNIX_FILE_METADATA_ITEM_TYPE),
 624                         .pops = NULL,
 625                         .label = "ctail",
 626                         .desc = "cryptcompress tail item",
 627                         .linkage = {NULL, NULL}
 628                 },
 629                 .b = {
 630                         .max_key_inside = max_key_inside_tail,
 631                         .can_contain_key = can_contain_key_ctail,
 632                         .mergeable = mergeable_ctail,
 633                         .nr_units = nr_units_ctail,
 634                         .lookup = NULL,
 635                         .init = init_ctail,
 636                         .paste = paste_ctail,
 637                         .fast_paste = agree_to_fast_op,
 638                         .can_shift = can_shift_ctail,
 639                         .create_hook = create_hook_ctail,
 640                         .copy_units = copy_units_ctail,
 641                         .kill_hook = kill_hook_ctail,
 642                         .shift_hook = shift_hook_ctail,
 643                         .cut_units = cut_units_ctail,
 644                         .kill_units = kill_units_ctail,
 645                         .unit_key = unit_key_tail,
 646                         .max_unit_key = unit_key_tail,
 647                         .estimate = estimate_ctail,
 648                         .item_data_by_flow = NULL,
 649 #if REISER4_DEBUG
 650                         .check = check_ctail
 651 #endif
 652                 },
 653                 .f = {
 654                         .utmost_child = utmost_child_ctail,
 655                         /* FIXME-EDWARD: write this */
 656                         .utmost_child_real_block = NULL,
 657                         .update = NULL,
 658                         .scan = scan_ctail,
 659                         .convert = convert_ctail
 660                 },
 661                 .s = {
 662                         .file = {
 663                                 .write = NULL,
 664                                 .read = read_ctail,
 665                                 .readpage = readpage_ctail,
 666                                 .get_block = get_block_address_tail,
 667                                 .append_key = append_key_ctail,
 668                                 .init_coord_extension =
 669                                 init_coord_extension_tail
 670                         }
 671                 }
 672         },
 673         [BLACK_BOX_ID] = {
 674                 .h = {
 675                         .type_id = REISER4_ITEM_PLUGIN_TYPE,
 676                         .id = BLACK_BOX_ID,
 677                         .groups = (1 << OTHER_ITEM_TYPE),
 678                         .pops = NULL,
 679                         .label = "blackbox",
 680                         .desc = "black box item",
 681                         .linkage = {NULL, NULL}
 682                 },
 683                 .b = {
 684                         .max_key_inside = NULL,
 685                         .can_contain_key = NULL,
 686                         .mergeable = not_mergeable,
 687                         .nr_units = nr_units_single_unit,
 688                         /* to need for ->lookup method */
 689                         .lookup = NULL,
 690                         .init = NULL,
 691                         .paste = NULL,
 692                         .fast_paste = NULL,
 693                         .can_shift = NULL,
 694                         .copy_units = NULL,
 695                         .create_hook = NULL,
 696                         .kill_hook = NULL,
 697                         .shift_hook = NULL,
 698                         .cut_units = NULL,
 699                         .kill_units = NULL,
 700                         .unit_key = NULL,
 701                         .max_unit_key = NULL,
 702                         .estimate = NULL,
 703                         .item_data_by_flow = NULL,
 704 #if REISER4_DEBUG
 705                         .check = NULL
 706 #endif
 707                 }
 708         }
 709 };
 710
 711 /* Make Linus happy.
 712    Local variables:
 713    c-indentation-style: "K&R"
 714    mode-name: "LC"
 715    c-basic-offset: 8
 716    tab-width: 8
 717    fill-column: 120
 718    End:
 719 */