root/fs/ext2/inode.c

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DEFINITIONS

This source file includes following definitions.
  1. ext2_put_inode
  2. block_bmap
  3. ext2_discard_prealloc
  4. ext2_alloc_block
  5. ext2_bmap
  6. inode_getblk
  7. block_getblk
  8. block_getcluster
  9. ext2_getblk
  10. ext2_getcluster
  11. ext2_bread
  12. ext2_read_inode
  13. ext2_update_inode
  14. ext2_write_inode
  15. ext2_sync_inode

   1 /*
   2  *  linux/fs/ext2/inode.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Goal-directed block allocation by Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
  16  */
  17 
  18 #include <asm/segment.h>
  19 #include <asm/system.h>
  20 
  21 #include <linux/errno.h>
  22 #include <linux/fs.h>
  23 #include <linux/ext2_fs.h>
  24 #include <linux/sched.h>
  25 #include <linux/stat.h>
  26 #include <linux/string.h>
  27 #include <linux/locks.h>
  28 #include <linux/mm.h>
  29 
  30 void ext2_put_inode (struct inode * inode)
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  31 {
  32         ext2_discard_prealloc (inode);
  33         if (inode->i_nlink || inode->i_ino == EXT2_ACL_IDX_INO ||
  34             inode->i_ino == EXT2_ACL_DATA_INO)
  35                 return;
  36         inode->i_size = 0;
  37         if (inode->i_blocks)
  38                 ext2_truncate (inode);
  39         ext2_free_inode (inode);
  40 }
  41 
  42 #define inode_bmap(inode, nr) ((inode)->u.ext2_i.i_data[(nr)])
  43 
  44 static int block_bmap (struct buffer_head * bh, int nr)
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  45 {
  46         int tmp;
  47 
  48         if (!bh)
  49                 return 0;
  50         tmp = ((u32 *) bh->b_data)[nr];
  51         brelse (bh);
  52         return tmp;
  53 }
  54 
  55 /* 
  56  * ext2_discard_prealloc and ext2_alloc_block are atomic wrt. the
  57  * superblock in the same manner as are ext2_free_blocks and
  58  * ext2_new_block.  We just wait on the super rather than locking it
  59  * here, since ext2_new_block will do the necessary locking and we
  60  * can't block until then.
  61  */
  62 void ext2_discard_prealloc (struct inode * inode)
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  63 {
  64 #ifdef EXT2_PREALLOCATE
  65         if (inode->u.ext2_i.i_prealloc_count) {
  66                 int i = inode->u.ext2_i.i_prealloc_count;
  67                 inode->u.ext2_i.i_prealloc_count = 0;
  68                 ext2_free_blocks (inode->i_sb,
  69                                   inode->u.ext2_i.i_prealloc_block,
  70                                   i);
  71         }
  72 #endif
  73 }
  74 
  75 static int ext2_alloc_block (struct inode * inode, unsigned long goal)
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  76 {
  77 #ifdef EXT2FS_DEBUG
  78         static unsigned long alloc_hits = 0, alloc_attempts = 0;
  79 #endif
  80         unsigned long result;
  81         struct buffer_head * bh;
  82 
  83         wait_on_super (inode->i_sb);
  84 
  85 #ifdef EXT2_PREALLOCATE
  86         if (inode->u.ext2_i.i_prealloc_count &&
  87             (goal == inode->u.ext2_i.i_prealloc_block ||
  88              goal + 1 == inode->u.ext2_i.i_prealloc_block))
  89         {               
  90                 result = inode->u.ext2_i.i_prealloc_block++;
  91                 inode->u.ext2_i.i_prealloc_count--;
  92                 ext2_debug ("preallocation hit (%lu/%lu).\n",
  93                             ++alloc_hits, ++alloc_attempts);
  94 
  95                 /* It doesn't matter if we block in getblk() since
  96                    we have already atomically allocated the block, and
  97                    are only clearing it now. */
  98                 if (!(bh = getblk (inode->i_sb->s_dev, result,
  99                                    inode->i_sb->s_blocksize))) {
 100                         ext2_error (inode->i_sb, "ext2_alloc_block",
 101                                     "cannot get block %lu", result);
 102                         return 0;
 103                 }
 104                 memset(bh->b_data, 0, inode->i_sb->s_blocksize);
 105                 bh->b_uptodate = 1;
 106                 mark_buffer_dirty(bh, 1);
 107                 brelse (bh);
 108         } else {
 109                 ext2_discard_prealloc (inode);
 110                 ext2_debug ("preallocation miss (%lu/%lu).\n",
 111                             alloc_hits, ++alloc_attempts);
 112                 if (S_ISREG(inode->i_mode))
 113                         result = ext2_new_block
 114                                 (inode->i_sb, goal,
 115                                  &inode->u.ext2_i.i_prealloc_count,
 116                                  &inode->u.ext2_i.i_prealloc_block);
 117                 else
 118                         result = ext2_new_block (inode->i_sb, goal, 0, 0);
 119         }
 120 #else
 121         result = ext2_new_block (inode->i_sb, goal, 0, 0);
 122 #endif
 123 
 124         return result;
 125 }
 126 
 127 
 128 int ext2_bmap (struct inode * inode, int block)
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 129 {
 130         int i;
 131         int addr_per_block = EXT2_ADDR_PER_BLOCK(inode->i_sb);
 132 
 133         if (block < 0) {
 134                 ext2_warning (inode->i_sb, "ext2_bmap", "block < 0");
 135                 return 0;
 136         }
 137         if (block >= EXT2_NDIR_BLOCKS + addr_per_block +
 138                      addr_per_block * addr_per_block +
 139                      addr_per_block * addr_per_block * addr_per_block) {
 140                 ext2_warning (inode->i_sb, "ext2_bmap", "block > big");
 141                 return 0;
 142         }
 143         if (block < EXT2_NDIR_BLOCKS)
 144                 return inode_bmap (inode, block);
 145         block -= EXT2_NDIR_BLOCKS;
 146         if (block < addr_per_block) {
 147                 i = inode_bmap (inode, EXT2_IND_BLOCK);
 148                 if (!i)
 149                         return 0;
 150                 return block_bmap (bread (inode->i_dev, i,
 151                                           inode->i_sb->s_blocksize), block);
 152         }
 153         block -= addr_per_block;
 154         if (block < addr_per_block * addr_per_block) {
 155                 i = inode_bmap (inode, EXT2_DIND_BLOCK);
 156                 if (!i)
 157                         return 0;
 158                 i = block_bmap (bread (inode->i_dev, i,
 159                                        inode->i_sb->s_blocksize),
 160                                 block / addr_per_block);
 161                 if (!i)
 162                         return 0;
 163                 return block_bmap (bread (inode->i_dev, i,
 164                                           inode->i_sb->s_blocksize),
 165                                    block & (addr_per_block - 1));
 166         }
 167         block -= addr_per_block * addr_per_block;
 168         i = inode_bmap (inode, EXT2_TIND_BLOCK);
 169         if (!i)
 170                 return 0;
 171         i = block_bmap (bread (inode->i_dev, i, inode->i_sb->s_blocksize),
 172                         block / (addr_per_block * addr_per_block));
 173         if (!i)
 174                 return 0;
 175         i = block_bmap (bread (inode->i_dev, i, inode->i_sb->s_blocksize),
 176                         (block / addr_per_block) & (addr_per_block - 1));
 177         if (!i)
 178                 return 0;
 179         return block_bmap (bread (inode->i_dev, i, inode->i_sb->s_blocksize),
 180                            block & (addr_per_block - 1));
 181 }
 182 
 183 static struct buffer_head * inode_getblk (struct inode * inode, int nr,
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 184                                           int create, int new_block, int * err)
 185 {
 186         u32 * p;
 187         int tmp, goal = 0;
 188         struct buffer_head * result;
 189         int blocks = inode->i_sb->s_blocksize / 512;
 190 
 191         p = inode->u.ext2_i.i_data + nr;
 192 repeat:
 193         tmp = *p;
 194         if (tmp) {
 195                 result = getblk (inode->i_dev, tmp, inode->i_sb->s_blocksize);
 196                 if (tmp == *p)
 197                         return result;
 198                 brelse (result);
 199                 goto repeat;
 200         }
 201         if (!create || new_block >= 
 202             (current->rlim[RLIMIT_FSIZE].rlim_cur >>
 203              EXT2_BLOCK_SIZE_BITS(inode->i_sb))) {
 204                 *err = -EFBIG;
 205                 return NULL;
 206         }
 207         if (inode->u.ext2_i.i_next_alloc_block == new_block)
 208                 goal = inode->u.ext2_i.i_next_alloc_goal;
 209 
 210         ext2_debug ("hint = %d,", goal);
 211 
 212         if (!goal) {
 213                 for (tmp = nr - 1; tmp >= 0; tmp--) {
 214                         if (inode->u.ext2_i.i_data[tmp]) {
 215                                 goal = inode->u.ext2_i.i_data[tmp];
 216                                 break;
 217                         }
 218                 }
 219                 if (!goal)
 220                         goal = (inode->u.ext2_i.i_block_group * 
 221                                 EXT2_BLOCKS_PER_GROUP(inode->i_sb)) +
 222                                inode->i_sb->u.ext2_sb.s_es->s_first_data_block;
 223         }
 224 
 225         ext2_debug ("goal = %d.\n", goal);
 226 
 227         tmp = ext2_alloc_block (inode, goal);
 228         if (!tmp)
 229                 return NULL;
 230         result = getblk (inode->i_dev, tmp, inode->i_sb->s_blocksize);
 231         if (*p) {
 232                 ext2_free_blocks (inode->i_sb, tmp, 1);
 233                 brelse (result);
 234                 goto repeat;
 235         }
 236         *p = tmp;
 237         inode->u.ext2_i.i_next_alloc_block = new_block;
 238         inode->u.ext2_i.i_next_alloc_goal = tmp;
 239         inode->i_ctime = CURRENT_TIME;
 240         inode->i_blocks += blocks;
 241         if (IS_SYNC(inode) || inode->u.ext2_i.i_osync)
 242                 ext2_sync_inode (inode);
 243         else
 244                 inode->i_dirt = 1;
 245         return result;
 246 }
 247 
 248 static struct buffer_head * block_getblk (struct inode * inode,
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 249                                           struct buffer_head * bh, int nr,
 250                                           int create, int blocksize, 
 251                                           int new_block, int * err)
 252 {
 253         int tmp, goal = 0;
 254         u32 * p;
 255         struct buffer_head * result;
 256         int blocks = inode->i_sb->s_blocksize / 512;
 257 
 258         if (!bh)
 259                 return NULL;
 260         if (!bh->b_uptodate) {
 261                 ll_rw_block (READ, 1, &bh);
 262                 wait_on_buffer (bh);
 263                 if (!bh->b_uptodate) {
 264                         brelse (bh);
 265                         return NULL;
 266                 }
 267         }
 268         p = (u32 *) bh->b_data + nr;
 269 repeat:
 270         tmp = *p;
 271         if (tmp) {
 272                 result = getblk (bh->b_dev, tmp, blocksize);
 273                 if (tmp == *p) {
 274                         brelse (bh);
 275                         return result;
 276                 }
 277                 brelse (result);
 278                 goto repeat;
 279         }
 280         if (!create || new_block >= 
 281             (current->rlim[RLIMIT_FSIZE].rlim_cur >> 
 282              EXT2_BLOCK_SIZE_BITS(inode->i_sb))) {
 283                 brelse (bh);
 284                 *err = -EFBIG;
 285                 return NULL;
 286         }
 287         if (inode->u.ext2_i.i_next_alloc_block == new_block)
 288                 goal = inode->u.ext2_i.i_next_alloc_goal;
 289         if (!goal) {
 290                 for (tmp = nr - 1; tmp >= 0; tmp--) {
 291                         if (((u32 *) bh->b_data)[tmp]) {
 292                                 goal = ((u32 *)bh->b_data)[tmp];
 293                                 break;
 294                         }
 295                 }
 296                 if (!goal)
 297                         goal = bh->b_blocknr;
 298         }
 299         tmp = ext2_alloc_block (inode, goal);
 300         if (!tmp) {
 301                 brelse (bh);
 302                 return NULL;
 303         }
 304         result = getblk (bh->b_dev, tmp, blocksize);
 305         if (*p) {
 306                 ext2_free_blocks (inode->i_sb, tmp, 1);
 307                 brelse (result);
 308                 goto repeat;
 309         }
 310         *p = tmp;
 311         mark_buffer_dirty(bh, 1);
 312         if (IS_SYNC(inode) || inode->u.ext2_i.i_osync) {
 313                 ll_rw_block (WRITE, 1, &bh);
 314                 wait_on_buffer (bh);
 315         }
 316         inode->i_ctime = CURRENT_TIME;
 317         inode->i_blocks += blocks;
 318         inode->i_dirt = 1;
 319         inode->u.ext2_i.i_next_alloc_block = new_block;
 320         inode->u.ext2_i.i_next_alloc_goal = tmp;
 321         brelse (bh);
 322         return result;
 323 }
 324 
 325 static int block_getcluster (struct inode * inode, struct buffer_head * bh,
     /* [previous][next][first][last][top][bottom][index][help] */
 326                                           int nr,
 327                                           int blocksize)
 328 {
 329         u32 * p;
 330         int firstblock = 0;
 331         int result = 0;
 332         int i;
 333 
 334         /* Check to see if clustering possible here. */
 335 
 336         if(!bh) return 0;
 337 
 338         if(nr % (PAGE_SIZE / inode->i_sb->s_blocksize) != 0) goto out;
 339         if(nr + 3 > EXT2_ADDR_PER_BLOCK(inode->i_sb)) goto out;
 340 
 341         for(i=0; i< (PAGE_SIZE / inode->i_sb->s_blocksize); i++) {
 342           p = (u32 *) bh->b_data + nr + i;
 343           
 344           /* All blocks in cluster must already be allocated */
 345           if(*p == 0) goto out;
 346           
 347           /* See if aligned correctly */
 348           if(i==0) firstblock = *p;
 349           else if(*p != firstblock + i) goto out;
 350         }
 351         
 352         p = (u32 *) bh->b_data + nr;
 353         result = generate_cluster(bh->b_dev, (int *) p, blocksize);
 354 
 355       out:
 356         brelse(bh);
 357         return result;
 358 }
 359 
 360 struct buffer_head * ext2_getblk (struct inode * inode, long block,
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 361                                   int create, int * err)
 362 {
 363         struct buffer_head * bh;
 364         unsigned long b;
 365         unsigned long addr_per_block = EXT2_ADDR_PER_BLOCK(inode->i_sb);
 366 
 367         *err = -EIO;
 368         if (block < 0) {
 369                 ext2_warning (inode->i_sb, "ext2_getblk", "block < 0");
 370                 return NULL;
 371         }
 372         if (block > EXT2_NDIR_BLOCKS + addr_per_block  +
 373                     addr_per_block * addr_per_block +
 374                     addr_per_block * addr_per_block * addr_per_block) {
 375                 ext2_warning (inode->i_sb, "ext2_getblk", "block > big");
 376                 return NULL;
 377         }
 378         /*
 379          * If this is a sequential block allocation, set the next_alloc_block
 380          * to this block now so that all the indblock and data block
 381          * allocations use the same goal zone
 382          */
 383 
 384         ext2_debug ("block %lu, next %lu, goal %lu.\n", block, 
 385                     inode->u.ext2_i.i_next_alloc_block,
 386                     inode->u.ext2_i.i_next_alloc_goal);
 387 
 388         if (block == inode->u.ext2_i.i_next_alloc_block + 1) {
 389                 inode->u.ext2_i.i_next_alloc_block++;
 390                 inode->u.ext2_i.i_next_alloc_goal++;
 391         }
 392 
 393         *err = -ENOSPC;
 394         b = block;
 395         if (block < EXT2_NDIR_BLOCKS)
 396                 return inode_getblk (inode, block, create, b, err);
 397         block -= EXT2_NDIR_BLOCKS;
 398         if (block < addr_per_block) {
 399                 bh = inode_getblk (inode, EXT2_IND_BLOCK, create, b, err);
 400                 return block_getblk (inode, bh, block, create,
 401                                      inode->i_sb->s_blocksize, b, err);
 402         }
 403         block -= addr_per_block;
 404         if (block < addr_per_block * addr_per_block) {
 405                 bh = inode_getblk (inode, EXT2_DIND_BLOCK, create, b, err);
 406                 bh = block_getblk (inode, bh, block / addr_per_block, create,
 407                                    inode->i_sb->s_blocksize, b, err);
 408                 return block_getblk (inode, bh, block & (addr_per_block - 1),
 409                                      create, inode->i_sb->s_blocksize, b, err);
 410         }
 411         block -= addr_per_block * addr_per_block;
 412         bh = inode_getblk (inode, EXT2_TIND_BLOCK, create, b, err);
 413         bh = block_getblk (inode, bh, block/(addr_per_block * addr_per_block),
 414                            create, inode->i_sb->s_blocksize, b, err);
 415         bh = block_getblk (inode, bh, (block/addr_per_block) & (addr_per_block - 1),
 416                            create, inode->i_sb->s_blocksize, b, err);
 417         return block_getblk (inode, bh, block & (addr_per_block - 1), create,
 418                              inode->i_sb->s_blocksize, b, err);
 419 }
 420 
 421 int ext2_getcluster (struct inode * inode, long block)
     /* [previous][next][first][last][top][bottom][index][help] */
 422 {
 423         struct buffer_head * bh;
 424         int err, create;
 425         unsigned long b;
 426         unsigned long addr_per_block = EXT2_ADDR_PER_BLOCK(inode->i_sb);
 427 
 428         create = 0;
 429         err = -EIO;
 430         if (block < 0) {
 431                 ext2_warning (inode->i_sb, "ext2_getblk", "block < 0");
 432                 return 0;
 433         }
 434         if (block > EXT2_NDIR_BLOCKS + addr_per_block  +
 435                     addr_per_block * addr_per_block +
 436                     addr_per_block * addr_per_block * addr_per_block) {
 437                 ext2_warning (inode->i_sb, "ext2_getblk", "block > big");
 438                 return 0;
 439         }
 440 
 441         err = -ENOSPC;
 442         b = block;
 443         if (block < EXT2_NDIR_BLOCKS) return 0;
 444 
 445         block -= EXT2_NDIR_BLOCKS;
 446 
 447         if (block < addr_per_block) {
 448                 bh = inode_getblk (inode, EXT2_IND_BLOCK, create, b, &err);
 449                 return block_getcluster (inode, bh, block, 
 450                                          inode->i_sb->s_blocksize);
 451         }
 452         block -= addr_per_block;
 453         if (block < addr_per_block * addr_per_block) {
 454                 bh = inode_getblk (inode, EXT2_DIND_BLOCK, create, b, &err);
 455                 bh = block_getblk (inode, bh, block / addr_per_block, create,
 456                                    inode->i_sb->s_blocksize, b, &err);
 457                 return block_getcluster (inode, bh, block & (addr_per_block - 1),
 458                                      inode->i_sb->s_blocksize);
 459         }
 460         block -= addr_per_block * addr_per_block;
 461         bh = inode_getblk (inode, EXT2_TIND_BLOCK, create, b, &err);
 462         bh = block_getblk (inode, bh, block/(addr_per_block * addr_per_block),
 463                            create, inode->i_sb->s_blocksize, b, &err);
 464         bh = block_getblk (inode, bh, (block/addr_per_block) & (addr_per_block - 1),
 465                            create, inode->i_sb->s_blocksize, b, &err);
 466         return block_getcluster (inode, bh, block & (addr_per_block - 1),
 467                                  inode->i_sb->s_blocksize);
 468 }
 469 
 470 struct buffer_head * ext2_bread (struct inode * inode, int block, 
     /* [previous][next][first][last][top][bottom][index][help] */
 471                                  int create, int *err)
 472 {
 473         struct buffer_head * bh;
 474 
 475         bh = ext2_getblk (inode, block, create, err);
 476         if (!bh || bh->b_uptodate)
 477                 return bh;
 478         ll_rw_block (READ, 1, &bh);
 479         wait_on_buffer (bh);
 480         if (bh->b_uptodate)
 481                 return bh;
 482         brelse (bh);
 483         *err = -EIO;
 484         return NULL;
 485 }
 486 
 487 void ext2_read_inode (struct inode * inode)
     /* [previous][next][first][last][top][bottom][index][help] */
 488 {
 489         struct buffer_head * bh;
 490         struct ext2_inode * raw_inode;
 491         unsigned long block_group;
 492         unsigned long group_desc;
 493         unsigned long desc;
 494         unsigned long block;
 495         struct ext2_group_desc * gdp;
 496 
 497         if ((inode->i_ino != EXT2_ROOT_INO && inode->i_ino != EXT2_ACL_IDX_INO &&
 498              inode->i_ino != EXT2_ACL_DATA_INO && inode->i_ino < EXT2_FIRST_INO) ||
 499             inode->i_ino > inode->i_sb->u.ext2_sb.s_es->s_inodes_count) {
 500                 ext2_error (inode->i_sb, "ext2_read_inode",
 501                             "bad inode number: %lu", inode->i_ino);
 502                 return;
 503         }
 504         block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb);
 505         if (block_group >= inode->i_sb->u.ext2_sb.s_groups_count)
 506                 ext2_panic (inode->i_sb, "ext2_read_inode",
 507                             "group >= groups count");
 508         group_desc = block_group / EXT2_DESC_PER_BLOCK(inode->i_sb);
 509         desc = block_group % EXT2_DESC_PER_BLOCK(inode->i_sb);
 510         bh = inode->i_sb->u.ext2_sb.s_group_desc[group_desc];
 511         if (!bh)
 512                 ext2_panic (inode->i_sb, "ext2_read_inode",
 513                             "Descriptor not loaded");
 514         gdp = (struct ext2_group_desc *) bh->b_data;
 515         block = gdp[desc].bg_inode_table +
 516                 (((inode->i_ino - 1) % EXT2_INODES_PER_GROUP(inode->i_sb))
 517                  / EXT2_INODES_PER_BLOCK(inode->i_sb));
 518         if (!(bh = bread (inode->i_dev, block, inode->i_sb->s_blocksize)))
 519                 ext2_panic (inode->i_sb, "ext2_read_inode",
 520                             "unable to read i-node block - "
 521                             "inode=%lu, block=%lu", inode->i_ino, block);
 522         raw_inode = ((struct ext2_inode *) bh->b_data) +
 523                 (inode->i_ino - 1) % EXT2_INODES_PER_BLOCK(inode->i_sb);
 524         inode->i_mode = raw_inode->i_mode;
 525         inode->i_uid = raw_inode->i_uid;
 526         inode->i_gid = raw_inode->i_gid;
 527         inode->i_nlink = raw_inode->i_links_count;
 528         inode->i_size = raw_inode->i_size;
 529         inode->i_atime = raw_inode->i_atime;
 530         inode->i_ctime = raw_inode->i_ctime;
 531         inode->i_mtime = raw_inode->i_mtime;
 532         inode->u.ext2_i.i_dtime = raw_inode->i_dtime;
 533         inode->i_blksize = inode->i_sb->s_blocksize;
 534         inode->i_blocks = raw_inode->i_blocks;
 535         inode->i_version = ++event;
 536         inode->u.ext2_i.i_flags = raw_inode->i_flags;
 537         inode->u.ext2_i.i_faddr = raw_inode->i_faddr;
 538         inode->u.ext2_i.i_frag_no = raw_inode->i_frag;
 539         inode->u.ext2_i.i_frag_size = raw_inode->i_fsize;
 540         inode->u.ext2_i.i_osync = 0;
 541         inode->u.ext2_i.i_file_acl = raw_inode->i_file_acl;
 542         inode->u.ext2_i.i_dir_acl = raw_inode->i_dir_acl;
 543         inode->u.ext2_i.i_version = raw_inode->i_version;
 544         inode->u.ext2_i.i_block_group = block_group;
 545         inode->u.ext2_i.i_next_alloc_block = 0;
 546         inode->u.ext2_i.i_next_alloc_goal = 0;
 547         if (inode->u.ext2_i.i_prealloc_count)
 548                 ext2_error (inode->i_sb, "ext2_read_inode",
 549                             "New inode has non-zero prealloc count!");
 550         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 551                 inode->i_rdev = raw_inode->i_block[0];
 552         else for (block = 0; block < EXT2_N_BLOCKS; block++)
 553                 inode->u.ext2_i.i_data[block] = raw_inode->i_block[block];
 554         brelse (bh);
 555         inode->i_op = NULL;
 556         if (inode->i_ino == EXT2_ACL_IDX_INO ||
 557             inode->i_ino == EXT2_ACL_DATA_INO)
 558                 /* Nothing to do */ ;
 559         else if (S_ISREG(inode->i_mode))
 560                 inode->i_op = &ext2_file_inode_operations;
 561         else if (S_ISDIR(inode->i_mode))
 562                 inode->i_op = &ext2_dir_inode_operations;
 563         else if (S_ISLNK(inode->i_mode))
 564                 inode->i_op = &ext2_symlink_inode_operations;
 565         else if (S_ISCHR(inode->i_mode))
 566                 inode->i_op = &chrdev_inode_operations;
 567         else if (S_ISBLK(inode->i_mode))
 568                 inode->i_op = &blkdev_inode_operations;
 569         else if (S_ISFIFO(inode->i_mode))
 570                 init_fifo(inode);
 571         if (inode->u.ext2_i.i_flags & EXT2_SYNC_FL)
 572                 inode->i_flags |= MS_SYNCHRONOUS;
 573         if (inode->u.ext2_i.i_flags & EXT2_APPEND_FL)
 574                 inode->i_flags |= S_APPEND;
 575         if (inode->u.ext2_i.i_flags & EXT2_IMMUTABLE_FL)
 576                 inode->i_flags |= S_IMMUTABLE;
 577 }
 578 
 579 static struct buffer_head * ext2_update_inode (struct inode * inode)
     /* [previous][next][first][last][top][bottom][index][help] */
 580 {
 581         struct buffer_head * bh;
 582         struct ext2_inode * raw_inode;
 583         unsigned long block_group;
 584         unsigned long group_desc;
 585         unsigned long desc;
 586         unsigned long block;
 587         struct ext2_group_desc * gdp;
 588 
 589         if ((inode->i_ino != EXT2_ROOT_INO && inode->i_ino < EXT2_FIRST_INO) ||
 590             inode->i_ino > inode->i_sb->u.ext2_sb.s_es->s_inodes_count) {
 591                 ext2_error (inode->i_sb, "ext2_write_inode",
 592                             "bad inode number: %lu", inode->i_ino);
 593                 return 0;
 594         }
 595         block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb);
 596         if (block_group >= inode->i_sb->u.ext2_sb.s_groups_count)
 597                 ext2_panic (inode->i_sb, "ext2_write_inode",
 598                             "group >= groups count");
 599         group_desc = block_group / EXT2_DESC_PER_BLOCK(inode->i_sb);
 600         desc = block_group % EXT2_DESC_PER_BLOCK(inode->i_sb);
 601         bh = inode->i_sb->u.ext2_sb.s_group_desc[group_desc];
 602         if (!bh)
 603                 ext2_panic (inode->i_sb, "ext2_write_inode",
 604                             "Descriptor not loaded");
 605         gdp = (struct ext2_group_desc *) bh->b_data;
 606         block = gdp[desc].bg_inode_table +
 607                 (((inode->i_ino - 1) % EXT2_INODES_PER_GROUP(inode->i_sb))
 608                  / EXT2_INODES_PER_BLOCK(inode->i_sb));
 609         if (!(bh = bread (inode->i_dev, block, inode->i_sb->s_blocksize)))
 610                 ext2_panic (inode->i_sb, "ext2_write_inode",
 611                             "unable to read i-node block - "
 612                             "inode=%lu, block=%lu", inode->i_ino, block);
 613         raw_inode = ((struct ext2_inode *)bh->b_data) +
 614                 (inode->i_ino - 1) % EXT2_INODES_PER_BLOCK(inode->i_sb);
 615         raw_inode->i_mode = inode->i_mode;
 616         raw_inode->i_uid = inode->i_uid;
 617         raw_inode->i_gid = inode->i_gid;
 618         raw_inode->i_links_count = inode->i_nlink;
 619         raw_inode->i_size = inode->i_size;
 620         raw_inode->i_atime = inode->i_atime;
 621         raw_inode->i_ctime = inode->i_ctime;
 622         raw_inode->i_mtime = inode->i_mtime;
 623         raw_inode->i_blocks = inode->i_blocks;
 624         raw_inode->i_dtime = inode->u.ext2_i.i_dtime;
 625         raw_inode->i_flags = inode->u.ext2_i.i_flags;
 626         raw_inode->i_faddr = inode->u.ext2_i.i_faddr;
 627         raw_inode->i_frag = inode->u.ext2_i.i_frag_no;
 628         raw_inode->i_fsize = inode->u.ext2_i.i_frag_size;
 629         raw_inode->i_file_acl = inode->u.ext2_i.i_file_acl;
 630         raw_inode->i_dir_acl = inode->u.ext2_i.i_dir_acl;
 631         raw_inode->i_version = inode->u.ext2_i.i_version;
 632         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 633                 raw_inode->i_block[0] = inode->i_rdev;
 634         else for (block = 0; block < EXT2_N_BLOCKS; block++)
 635                 raw_inode->i_block[block] = inode->u.ext2_i.i_data[block];
 636         mark_buffer_dirty(bh, 1);
 637         inode->i_dirt = 0;
 638         return bh;
 639 }
 640 
 641 void ext2_write_inode (struct inode * inode)
     /* [previous][next][first][last][top][bottom][index][help] */
 642 {
 643         struct buffer_head * bh;
 644         bh = ext2_update_inode (inode);
 645         brelse (bh);
 646 }
 647 
 648 int ext2_sync_inode (struct inode *inode)
     /* [previous][next][first][last][top][bottom][index][help] */
 649 {
 650         int err = 0;
 651         struct buffer_head *bh;
 652 
 653         bh = ext2_update_inode (inode);
 654         if (bh && bh->b_dirt)
 655         {
 656                 ll_rw_block (WRITE, 1, &bh);
 657                 wait_on_buffer (bh);
 658                 if (bh->b_req && !bh->b_uptodate)
 659                 {
 660                         printk ("IO error syncing ext2 inode [%04x:%08lx]\n",
 661                                 inode->i_dev, inode->i_ino);
 662                         err = -1;
 663                 }
 664         }
 665         else if (!bh)
 666                 err = -1;
 667         brelse (bh);
 668         return err;
 669 }

/* [previous][next][first][last][top][bottom][index][help] */