sys/gnu/ext2fs/ext2_linux_balloc.c

   1 /*
   2  *  modified for Lites 1.1
   3  *
   4  *  Aug 1995, Godmar Back (gback@cs.utah.edu)
   5  *  University of Utah, Department of Computer Science
   6  */
   7 /*
   8  *  linux/fs/ext2/balloc.c
   9  *
  10  * Copyright (C) 1992, 1993, 1994, 1995
  11  * Remy Card (card@masi.ibp.fr)
  12  * Laboratoire MASI - Institut Blaise Pascal
  13  * Universite Pierre et Marie Curie (Paris VI)
  14  *
  15  *  Enhanced block allocation by Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
  16  */
  17
  18 /*
  19  * The free blocks are managed by bitmaps.  A file system contains several
  20  * blocks groups.  Each group contains 1 bitmap block for blocks, 1 bitmap
  21  * block for inodes, N blocks for the inode table and data blocks.
  22  *
  23  * The file system contains group descriptors which are located after the
  24  * super block.  Each descriptor contains the number of the bitmap block and
  25  * the free blocks count in the block.  The descriptors are loaded in memory
  26  * when a file system is mounted (see ext2_read_super).
  27  */
  28
  29 #include <sys/param.h>
  30 #include <sys/systm.h>
  31 #include <sys/proc.h>
  32 #include <sys/mount.h>
  33 #include <sys/vnode.h>
  34
  35 #include <ufs/ufs/quota.h>
  36 #include <ufs/ufs/ufsmount.h>
  37 #include <gnu/ext2fs/ext2_extern.h>
  38 #include <gnu/ext2fs/ext2_fs.h>
  39 #include <gnu/ext2fs/ext2_fs_sb.h>
  40 #include <gnu/ext2fs/fs.h>
  41
  42 #ifdef __i386__
  43 #include <gnu/ext2fs/i386-bitops.h>
  44 #else
  45 #error Provide an bitops.h file, please !
  46 #endif
  47
  48 #define in_range(b, first, len)         ((b) >= (first) && (b) <= (first) + (len) - 1)
  49
  50 /* got rid of get_group_desc since it can already be found in
  51  * ext2_linux_ialloc.c
  52  */
  53
  54 static void read_block_bitmap (struct mount * mp,
  55                                unsigned int block_group,
  56                                unsigned long bitmap_nr)
  57 {
  58         struct ext2_sb_info *sb = VFSTOUFS(mp)->um_e2fs;
  59         struct ext2_group_desc * gdp;
  60         struct buffer_head * bh;
  61         int    error;
  62
  63         gdp = get_group_desc (mp, block_group, NULL);
  64         if ((error = bread (VFSTOUFS(mp)->um_devvp,
  65                 fsbtodb(sb, gdp->bg_block_bitmap),sb->s_blocksize, NOCRED, &bh)) != 0)
  66                 panic ( "read_block_bitmap: "
  67                             "Cannot read block bitmap - "
  68                             "block_group = %d, block_bitmap = %lu",
  69                             block_group, (unsigned long) gdp->bg_block_bitmap);
  70         sb->s_block_bitmap_number[bitmap_nr] = block_group;
  71         sb->s_block_bitmap[bitmap_nr] = bh;
  72         LCK_BUF(bh)
  73 }
  74
  75 /*
  76  * load_block_bitmap loads the block bitmap for a blocks group
  77  *
  78  * It maintains a cache for the last bitmaps loaded.  This cache is managed
  79  * with a LRU algorithm.
  80  *
  81  * Notes:
  82  * 1/ There is one cache per mounted file system.
  83  * 2/ If the file system contains less than EXT2_MAX_GROUP_LOADED groups,
  84  *    this function reads the bitmap without maintaining a LRU cache.
  85  */
  86 static int load__block_bitmap (struct mount * mp,
  87                                unsigned int block_group)
  88 {
  89         int i, j;
  90         struct ext2_sb_info *sb = VFSTOUFS(mp)->um_e2fs;
  91         unsigned long block_bitmap_number;
  92         struct buffer_head * block_bitmap;
  93
  94         if (block_group >= sb->s_groups_count)
  95                 panic ( "load_block_bitmap: "
  96                             "block_group >= groups_count - "
  97                             "block_group = %d, groups_count = %lu",
  98                             block_group, sb->s_groups_count);
  99
 100         if (sb->s_groups_count <= EXT2_MAX_GROUP_LOADED) {
 101                 if (sb->s_block_bitmap[block_group]) {
 102                         if (sb->s_block_bitmap_number[block_group] !=
 103                             block_group)
 104                                 panic ( "load_block_bitmap: "
 105                                             "block_group != block_bitmap_number");
 106                         else
 107                                 return block_group;
 108                 } else {
 109                         read_block_bitmap (mp, block_group, block_group);
 110                         return block_group;
 111                 }
 112         }
 113
 114         for (i = 0; i < sb->s_loaded_block_bitmaps &&
 115                     sb->s_block_bitmap_number[i] != block_group; i++)
 116                 ;
 117         if (i < sb->s_loaded_block_bitmaps &&
 118             sb->s_block_bitmap_number[i] == block_group) {
 119                 block_bitmap_number = sb->s_block_bitmap_number[i];
 120                 block_bitmap = sb->s_block_bitmap[i];
 121                 for (j = i; j > 0; j--) {
 122                         sb->s_block_bitmap_number[j] =
 123                                 sb->s_block_bitmap_number[j - 1];
 124                         sb->s_block_bitmap[j] =
 125                                 sb->s_block_bitmap[j - 1];
 126                 }
 127                 sb->s_block_bitmap_number[0] = block_bitmap_number;
 128                 sb->s_block_bitmap[0] = block_bitmap;
 129         } else {
 130                 if (sb->s_loaded_block_bitmaps < EXT2_MAX_GROUP_LOADED)
 131                         sb->s_loaded_block_bitmaps++;
 132                 else
 133                         ULCK_BUF(sb->s_block_bitmap[EXT2_MAX_GROUP_LOADED - 1])
 134
 135                 for (j = sb->s_loaded_block_bitmaps - 1; j > 0;  j--) {
 136                         sb->s_block_bitmap_number[j] =
 137                                 sb->s_block_bitmap_number[j - 1];
 138                         sb->s_block_bitmap[j] =
 139                                 sb->s_block_bitmap[j - 1];
 140                 }
 141                 read_block_bitmap (mp, block_group, 0);
 142         }
 143         return 0;
 144 }
 145
 146 static __inline int load_block_bitmap (struct mount * mp,
 147                                        unsigned int block_group)
 148 {
 149         struct ext2_sb_info *sb = VFSTOUFS(mp)->um_e2fs;
 150         if (sb->s_loaded_block_bitmaps > 0 &&
 151             sb->s_block_bitmap_number[0] == block_group)
 152                 return 0;
 153
 154         if (sb->s_groups_count <= EXT2_MAX_GROUP_LOADED &&
 155             sb->s_block_bitmap_number[block_group] == block_group &&
 156             sb->s_block_bitmap[block_group])
 157                 return block_group;
 158
 159         return load__block_bitmap (mp, block_group);
 160 }
 161
 162 void ext2_free_blocks (struct mount * mp, unsigned long block,
 163                        unsigned long count)
 164 {
 165         struct ext2_sb_info *sb = VFSTOUFS(mp)->um_e2fs;
 166         struct buffer_head * bh;
 167         struct buffer_head * bh2;
 168         unsigned long block_group;
 169         unsigned long bit;
 170         unsigned long i;
 171         int bitmap_nr;
 172         struct ext2_group_desc * gdp;
 173         struct ext2_super_block * es = sb->s_es;
 174
 175         if (!sb) {
 176                 printf ("ext2_free_blocks: nonexistent device");
 177                 return;
 178         }
 179         lock_super (VFSTOUFS(mp)->um_devvp);
 180         if (block < es->s_first_data_block ||
 181             (block + count) > es->s_blocks_count) {
 182                 printf ( "ext2_free_blocks: "
 183                             "Freeing blocks not in datazone - "
 184                             "block = %lu, count = %lu", block, count);
 185                 unlock_super (VFSTOUFS(mp)->um_devvp);
 186                 return;
 187         }
 188
 189         ext2_debug ("freeing blocks %lu to %lu\n", block, block+count-1);
 190
 191         block_group = (block - es->s_first_data_block) /
 192                       EXT2_BLOCKS_PER_GROUP(sb);
 193         bit = (block - es->s_first_data_block) % EXT2_BLOCKS_PER_GROUP(sb);
 194         if (bit + count > EXT2_BLOCKS_PER_GROUP(sb))
 195                 panic ( "ext2_free_blocks: "
 196                             "Freeing blocks across group boundary - "
 197                             "Block = %lu, count = %lu",
 198                             block, count);
 199         bitmap_nr = load_block_bitmap (mp, block_group);
 200         bh = sb->s_block_bitmap[bitmap_nr];
 201         gdp = get_group_desc (mp, block_group, &bh2);
 202
 203         if (/* test_opt (sb, CHECK_STRICT) &&   assume always strict ! */
 204             (in_range (gdp->bg_block_bitmap, block, count) ||
 205              in_range (gdp->bg_inode_bitmap, block, count) ||
 206              in_range (block, gdp->bg_inode_table,
 207                        sb->s_itb_per_group) ||
 208              in_range (block + count - 1, gdp->bg_inode_table,
 209                        sb->s_itb_per_group)))
 210                 panic ( "ext2_free_blocks: "
 211                             "Freeing blocks in system zones - "
 212                             "Block = %lu, count = %lu",
 213                             block, count);
 214
 215         for (i = 0; i < count; i++) {
 216                 if (!clear_bit (bit + i, bh->b_data))
 217                         printf ("ext2_free_blocks: "
 218                                       "bit already cleared for block %lu",
 219                                       block);
 220                 else {
 221                         gdp->bg_free_blocks_count++;
 222                         es->s_free_blocks_count++;
 223                 }
 224         }
 225
 226         mark_buffer_dirty(bh2);
 227         mark_buffer_dirty(bh);
 228 /****
 229         if (sb->s_flags & MS_SYNCHRONOUS) {
 230                 ll_rw_block (WRITE, 1, &bh);
 231                 wait_on_buffer (bh);
 232         }
 233 ****/
 234         sb->s_dirt = 1;
 235         unlock_super (VFSTOUFS(mp)->um_devvp);
 236         return;
 237 }
 238
 239 /*
 240  * ext2_new_block uses a goal block to assist allocation.  If the goal is
 241  * free, or there is a free block within 32 blocks of the goal, that block
 242  * is allocated.  Otherwise a forward search is made for a free block; within
 243  * each block group the search first looks for an entire free byte in the block
 244  * bitmap, and then for any free bit if that fails.
 245  */
 246 int ext2_new_block (struct mount * mp, unsigned long goal,
 247                     u_int32_t * prealloc_count,
 248                     u_int32_t * prealloc_block)
 249 {
 250         struct ext2_sb_info *sb = VFSTOUFS(mp)->um_e2fs;
 251         struct buffer_head * bh;
 252         struct buffer_head * bh2;
 253         char * p, * r;
 254         int i, j, k, tmp;
 255         int bitmap_nr;
 256         struct ext2_group_desc * gdp;
 257         struct ext2_super_block * es = sb->s_es;
 258
 259 #ifdef EXT2FS_DEBUG
 260         static int goal_hits = 0, goal_attempts = 0;
 261 #endif
 262         if (!sb) {
 263                 printf ("ext2_new_block: nonexistent device");
 264                 return 0;
 265         }
 266         lock_super (VFSTOUFS(mp)->um_devvp);
 267
 268         ext2_debug ("goal=%lu.\n", goal);
 269
 270 repeat:
 271         /*
 272          * First, test whether the goal block is free.
 273          */
 274         if (goal < es->s_first_data_block || goal >= es->s_blocks_count)
 275                 goal = es->s_first_data_block;
 276         i = (goal - es->s_first_data_block) / EXT2_BLOCKS_PER_GROUP(sb);
 277         gdp = get_group_desc (mp, i, &bh2);
 278         if (gdp->bg_free_blocks_count > 0) {
 279                 j = ((goal - es->s_first_data_block) % EXT2_BLOCKS_PER_GROUP(sb));
 280 #ifdef EXT2FS_DEBUG
 281                 if (j)
 282                         goal_attempts++;
 283 #endif
 284                 bitmap_nr = load_block_bitmap (mp, i);
 285                 bh = sb->s_block_bitmap[bitmap_nr];
 286
 287                 ext2_debug ("goal is at %d:%d.\n", i, j);
 288
 289                 if (!test_bit(j, bh->b_data)) {
 290 #ifdef EXT2FS_DEBUG
 291                         goal_hits++;
 292                         ext2_debug ("goal bit allocated.\n");
 293 #endif
 294                         goto got_block;
 295                 }
 296                 if (j) {
 297                         /*
 298                          * The goal was occupied; search forward for a free
 299                          * block within the next XX blocks.
 300                          *
 301                          * end_goal is more or less random, but it has to be
 302                          * less than EXT2_BLOCKS_PER_GROUP. Aligning up to the
 303                          * next 64-bit boundary is simple..
 304                          */
 305                         int end_goal = (j + 63) & ~63;
 306                         j = find_next_zero_bit(bh->b_data, end_goal, j);
 307                         if (j < end_goal)
 308                                 goto got_block;
 309                 }
 310
 311                 ext2_debug ("Bit not found near goal\n");
 312
 313                 /*
 314                  * There has been no free block found in the near vicinity
 315                  * of the goal: do a search forward through the block groups,
 316                  * searching in each group first for an entire free byte in
 317                  * the bitmap and then for any free bit.
 318                  *
 319                  * Search first in the remainder of the current group; then,
 320                  * cyclicly search through the rest of the groups.
 321                  */
 322                 p = ((char *) bh->b_data) + (j >> 3);
 323                 r = memscan(p, 0, (EXT2_BLOCKS_PER_GROUP(sb) - j + 7) >> 3);
 324                 k = (r - ((char *) bh->b_data)) << 3;
 325                 if (k < EXT2_BLOCKS_PER_GROUP(sb)) {
 326                         j = k;
 327                         goto search_back;
 328                 }
 329                 k = find_next_zero_bit ((unsigned long *) bh->b_data,
 330                                         EXT2_BLOCKS_PER_GROUP(sb),
 331                                         j);
 332                 if (k < EXT2_BLOCKS_PER_GROUP(sb)) {
 333                         j = k;
 334                         goto got_block;
 335                 }
 336         }
 337
 338         ext2_debug ("Bit not found in block group %d.\n", i);
 339
 340         /*
 341          * Now search the rest of the groups.  We assume that
 342          * i and gdp correctly point to the last group visited.
 343          */
 344         for (k = 0; k < sb->s_groups_count; k++) {
 345                 i++;
 346                 if (i >= sb->s_groups_count)
 347                         i = 0;
 348                 gdp = get_group_desc (mp, i, &bh2);
 349                 if (gdp->bg_free_blocks_count > 0)
 350                         break;
 351         }
 352         if (k >= sb->s_groups_count) {
 353                 unlock_super (VFSTOUFS(mp)->um_devvp);
 354                 return 0;
 355         }
 356         bitmap_nr = load_block_bitmap (mp, i);
 357         bh = sb->s_block_bitmap[bitmap_nr];
 358         r = memscan(bh->b_data, 0, EXT2_BLOCKS_PER_GROUP(sb) >> 3);
 359         j = (r - bh->b_data) << 3;
 360
 361         if (j < EXT2_BLOCKS_PER_GROUP(sb))
 362                 goto search_back;
 363         else
 364                 j = find_first_zero_bit ((unsigned long *) bh->b_data,
 365                                          EXT2_BLOCKS_PER_GROUP(sb));
 366         if (j >= EXT2_BLOCKS_PER_GROUP(sb)) {
 367                 printf ( "ext2_new_block: "
 368                          "Free blocks count corrupted for block group %d", i);
 369                 unlock_super (VFSTOUFS(mp)->um_devvp);
 370                 return 0;
 371         }
 372
 373 search_back:
 374         /*
 375          * We have succeeded in finding a free byte in the block
 376          * bitmap.  Now search backwards up to 7 bits to find the
 377          * start of this group of free blocks.
 378          */
 379         for (k = 0; k < 7 && j > 0 && !test_bit (j - 1, bh->b_data); k++, j--);
 380
 381 got_block:
 382
 383         ext2_debug ("using block group %d(%d)\n", i, gdp->bg_free_blocks_count);
 384
 385         tmp = j + i * EXT2_BLOCKS_PER_GROUP(sb) + es->s_first_data_block;
 386
 387         if (/* test_opt (sb, CHECK_STRICT) && we are always strict. */
 388             (tmp == gdp->bg_block_bitmap ||
 389              tmp == gdp->bg_inode_bitmap ||
 390              in_range (tmp, gdp->bg_inode_table, sb->s_itb_per_group)))
 391                 panic ( "ext2_new_block: "
 392                             "Allocating block in system zone - "
 393                             "%dth block = %u in group %u", j, tmp, i);
 394
 395         if (set_bit (j, bh->b_data)) {
 396                 printf ( "ext2_new_block: "
 397                          "bit already set for block %d", j);
 398                 goto repeat;
 399         }
 400
 401         ext2_debug ("found bit %d\n", j);
 402
 403         /*
 404          * Do block preallocation now if required.
 405          */
 406 #ifdef EXT2_PREALLOCATE
 407         if (prealloc_block) {
 408                 *prealloc_count = 0;
 409                 *prealloc_block = tmp + 1;
 410                 for (k = 1;
 411                      k < 8 && (j + k) < EXT2_BLOCKS_PER_GROUP(sb); k++) {
 412                         if (set_bit (j + k, bh->b_data))
 413                                 break;
 414                         (*prealloc_count)++;
 415                 }
 416                 gdp->bg_free_blocks_count -= *prealloc_count;
 417                 es->s_free_blocks_count -= *prealloc_count;
 418                 ext2_debug ("Preallocated a further %lu bits.\n",
 419                             *prealloc_count);
 420         }
 421 #endif
 422
 423         j = tmp;
 424
 425         mark_buffer_dirty(bh);
 426 /****
 427         if (sb->s_flags & MS_SYNCHRONOUS) {
 428                 ll_rw_block (WRITE, 1, &bh);
 429                 wait_on_buffer (bh);
 430         }
 431 ****/
 432         if (j >= es->s_blocks_count) {
 433                 printf ( "ext2_new_block: "
 434                             "block >= blocks count - "
 435                             "block_group = %d, block=%d", i, j);
 436                 unlock_super (VFSTOUFS(mp)->um_devvp);
 437                 return 0;
 438         }
 439
 440         ext2_debug ("allocating block %d. "
 441                     "Goal hits %d of %d.\n", j, goal_hits, goal_attempts);
 442
 443         gdp->bg_free_blocks_count--;
 444         mark_buffer_dirty(bh2);
 445         es->s_free_blocks_count--;
 446         sb->s_dirt = 1;
 447         unlock_super (VFSTOUFS(mp)->um_devvp);
 448         return j;
 449 }
 450
 451 #ifdef unused
 452 static unsigned long ext2_count_free_blocks (struct mount * mp)
 453 {
 454         struct ext2_sb_info *sb = VFSTOUFS(mp)->um_e2fs;
 455 #ifdef EXT2FS_DEBUG
 456         struct ext2_super_block * es;
 457         unsigned long desc_count, bitmap_count, x;
 458         int bitmap_nr;
 459         struct ext2_group_desc * gdp;
 460         int i;
 461
 462         lock_super (VFSTOUFS(mp)->um_devvp);
 463         es = sb->s_es;
 464         desc_count = 0;
 465         bitmap_count = 0;
 466         gdp = NULL;
 467         for (i = 0; i < sb->s_groups_count; i++) {
 468                 gdp = get_group_desc (mp, i, NULL);
 469                 desc_count += gdp->bg_free_blocks_count;
 470                 bitmap_nr = load_block_bitmap (mp, i);
 471                 x = ext2_count_free (sb->s_block_bitmap[bitmap_nr],
 472                                      sb->s_blocksize);
 473                 ext2_debug ("group %d: stored = %d, counted = %lu\n",
 474                         i, gdp->bg_free_blocks_count, x);
 475                 bitmap_count += x;
 476         }
 477         ext2_debug( "stored = %lu, computed = %lu, %lu\n",
 478                es->s_free_blocks_count, desc_count, bitmap_count);
 479         unlock_super (VFSTOUFS(mp)->um_devvp);
 480         return bitmap_count;
 481 #else
 482         return sb->s_es->s_free_blocks_count;
 483 #endif
 484 }
 485 #endif /* unused */
 486
 487 static __inline int block_in_use (unsigned long block,
 488                                   struct ext2_sb_info * sb,
 489                                   unsigned char * map)
 490 {
 491         return test_bit ((block - sb->s_es->s_first_data_block) %
 492                          EXT2_BLOCKS_PER_GROUP(sb), map);
 493 }
 494
 495 #ifdef unused
 496 static void ext2_check_blocks_bitmap (struct mount * mp)
 497 {
 498         struct ext2_sb_info *sb = VFSTOUFS(mp)->um_e2fs;
 499         struct buffer_head * bh;
 500         struct ext2_super_block * es;
 501         unsigned long desc_count, bitmap_count, x;
 502         unsigned long desc_blocks;
 503         int bitmap_nr;
 504         struct ext2_group_desc * gdp;
 505         int i, j;
 506
 507         lock_super (VFSTOUFS(mp)->um_devvp);
 508         es = sb->s_es;
 509         desc_count = 0;
 510         bitmap_count = 0;
 511         gdp = NULL;
 512         desc_blocks = (sb->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
 513                       EXT2_DESC_PER_BLOCK(sb);
 514         for (i = 0; i < sb->s_groups_count; i++) {
 515                 gdp = get_group_desc (mp, i, NULL);
 516                 desc_count += gdp->bg_free_blocks_count;
 517                 bitmap_nr = load_block_bitmap (mp, i);
 518                 bh = sb->s_block_bitmap[bitmap_nr];
 519
 520                 if (!test_bit (0, bh->b_data))
 521                         printf ( "ext2_check_blocks_bitmap: "
 522                                     "Superblock in group %d is marked free", i);
 523
 524                 for (j = 0; j < desc_blocks; j++)
 525                         if (!test_bit (j + 1, bh->b_data))
 526                                 printf ("ext2_check_blocks_bitmap: "
 527                                             "Descriptor block #%d in group "
 528                                             "%d is marked free", j, i);
 529
 530                 if (!block_in_use (gdp->bg_block_bitmap, sb, bh->b_data))
 531                         printf ("ext2_check_blocks_bitmap: "
 532                                     "Block bitmap for group %d is marked free",
 533                                     i);
 534
 535                 if (!block_in_use (gdp->bg_inode_bitmap, sb, bh->b_data))
 536                         printf ("ext2_check_blocks_bitmap: "
 537                                     "Inode bitmap for group %d is marked free",
 538                                     i);
 539
 540                 for (j = 0; j < sb->s_itb_per_group; j++)
 541                         if (!block_in_use (gdp->bg_inode_table + j, sb, bh->b_data))
 542                                 printf ("ext2_check_blocks_bitmap: "
 543                                             "Block #%d of the inode table in "
 544                                             "group %d is marked free", j, i);
 545
 546                 x = ext2_count_free (bh, sb->s_blocksize);
 547                 if (gdp->bg_free_blocks_count != x)
 548                         printf ("ext2_check_blocks_bitmap: "
 549                                     "Wrong free blocks count for group %d, "
 550                                     "stored = %d, counted = %lu", i,
 551                                     gdp->bg_free_blocks_count, x);
 552                 bitmap_count += x;
 553         }
 554         if (es->s_free_blocks_count != bitmap_count)
 555                 printf ("ext2_check_blocks_bitmap: "
 556                             "Wrong free blocks count in super block, "
 557                             "stored = %lu, counted = %lu",
 558                             (unsigned long) es->s_free_blocks_count, bitmap_count);
 559         unlock_super (VFSTOUFS(mp)->um_devvp);
 560 }
 561 #endif /* unused */
 562
 563 /*
 564  *  this function is taken from
 565  *  linux/fs/ext2/bitmap.c
 566  */
 567
 568 static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
 569
 570 unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars)
 571 {
 572         unsigned int i;
 573         unsigned long sum = 0;
 574
 575         if (!map)
 576                 return (0);
 577         for (i = 0; i < numchars; i++)
 578                 sum += nibblemap[map->b_data[i] & 0xf] +
 579                         nibblemap[(map->b_data[i] >> 4) & 0xf];
 580         return (sum);
 581 }