fs/minix/inode.c

   1 /*
   2  *  linux/fs/minix/inode.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  *
   6  *  Copyright (C) 1996  Gertjan van Wingerde
   7  *      Minix V2 fs support.
   8  *
   9  *  Modified for 680x0 by Andreas Schwab
  10  *  Updated to filesystem version 3 by Daniel Aragones
  11  */
  12
  13 #include <linux/module.h>
  14 #include "minix.h"
  15 #include <linux/buffer_head.h>
  16 #include <linux/slab.h>
  17 #include <linux/init.h>
  18 #include <linux/highuid.h>
  19 #include <linux/vfs.h>
  20 #include <linux/writeback.h>
  21
  22 static int minix_write_inode(struct inode *inode,
  23                 struct writeback_control *wbc);
  24 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
  25 static int minix_remount (struct super_block * sb, int * flags, char * data);
  26
  27 static void minix_delete_inode(struct inode *inode)
  28 {
  29         truncate_inode_pages(&inode->i_data, 0);
  30         inode->i_size = 0;
  31         minix_truncate(inode);
  32         minix_free_inode(inode);
  33 }
  34
  35 static void minix_put_super(struct super_block *sb)
  36 {
  37         int i;
  38         struct minix_sb_info *sbi = minix_sb(sb);
  39
  40         if (!(sb->s_flags & MS_RDONLY)) {
  41                 if (sbi->s_version != MINIX_V3)  /* s_state is now out from V3 sb */
  42                         sbi->s_ms->s_state = sbi->s_mount_state;
  43                 mark_buffer_dirty(sbi->s_sbh);
  44         }
  45         for (i = 0; i < sbi->s_imap_blocks; i++)
  46                 brelse(sbi->s_imap[i]);
  47         for (i = 0; i < sbi->s_zmap_blocks; i++)
  48                 brelse(sbi->s_zmap[i]);
  49         brelse (sbi->s_sbh);
  50         kfree(sbi->s_imap);
  51         sb->s_fs_info = NULL;
  52         kfree(sbi);
  53 }
  54
  55 static struct kmem_cache * minix_inode_cachep;
  56
  57 static struct inode *minix_alloc_inode(struct super_block *sb)
  58 {
  59         struct minix_inode_info *ei;
  60         ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, GFP_KERNEL);
  61         if (!ei)
  62                 return NULL;
  63         return &ei->vfs_inode;
  64 }
  65
  66 static void minix_destroy_inode(struct inode *inode)
  67 {
  68         kmem_cache_free(minix_inode_cachep, minix_i(inode));
  69 }
  70
  71 static void init_once(void *foo)
  72 {
  73         struct minix_inode_info *ei = (struct minix_inode_info *) foo;
  74
  75         inode_init_once(&ei->vfs_inode);
  76 }
  77
  78 static int init_inodecache(void)
  79 {
  80         minix_inode_cachep = kmem_cache_create("minix_inode_cache",
  81                                              sizeof(struct minix_inode_info),
  82                                              0, (SLAB_RECLAIM_ACCOUNT|
  83                                                 SLAB_MEM_SPREAD),
  84                                              init_once);
  85         if (minix_inode_cachep == NULL)
  86                 return -ENOMEM;
  87         return 0;
  88 }
  89
  90 static void destroy_inodecache(void)
  91 {
  92         kmem_cache_destroy(minix_inode_cachep);
  93 }
  94
  95 static const struct super_operations minix_sops = {
  96         .alloc_inode    = minix_alloc_inode,
  97         .destroy_inode  = minix_destroy_inode,
  98         .write_inode    = minix_write_inode,
  99         .delete_inode   = minix_delete_inode,
 100         .put_super      = minix_put_super,
 101         .statfs         = minix_statfs,
 102         .remount_fs     = minix_remount,
 103 };
 104
 105 static int minix_remount (struct super_block * sb, int * flags, char * data)
 106 {
 107         struct minix_sb_info * sbi = minix_sb(sb);
 108         struct minix_super_block * ms;
 109
 110         ms = sbi->s_ms;
 111         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
 112                 return 0;
 113         if (*flags & MS_RDONLY) {
 114                 if (ms->s_state & MINIX_VALID_FS ||
 115                     !(sbi->s_mount_state & MINIX_VALID_FS))
 116                         return 0;
 117                 /* Mounting a rw partition read-only. */
 118                 if (sbi->s_version != MINIX_V3)
 119                         ms->s_state = sbi->s_mount_state;
 120                 mark_buffer_dirty(sbi->s_sbh);
 121         } else {
 122                 /* Mount a partition which is read-only, read-write. */
 123                 if (sbi->s_version != MINIX_V3) {
 124                         sbi->s_mount_state = ms->s_state;
 125                         ms->s_state &= ~MINIX_VALID_FS;
 126                 } else {
 127                         sbi->s_mount_state = MINIX_VALID_FS;
 128                 }
 129                 mark_buffer_dirty(sbi->s_sbh);
 130
 131                 if (!(sbi->s_mount_state & MINIX_VALID_FS))
 132                         printk("MINIX-fs warning: remounting unchecked fs, "
 133                                 "running fsck is recommended\n");
 134                 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
 135                         printk("MINIX-fs warning: remounting fs with errors, "
 136                                 "running fsck is recommended\n");
 137         }
 138         return 0;
 139 }
 140
 141 static int minix_fill_super(struct super_block *s, void *data, int silent)
 142 {
 143         struct buffer_head *bh;
 144         struct buffer_head **map;
 145         struct minix_super_block *ms;
 146         struct minix3_super_block *m3s = NULL;
 147         unsigned long i, block;
 148         struct inode *root_inode;
 149         struct minix_sb_info *sbi;
 150         int ret = -EINVAL;
 151
 152         sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
 153         if (!sbi)
 154                 return -ENOMEM;
 155         s->s_fs_info = sbi;
 156
 157         BUILD_BUG_ON(32 != sizeof (struct minix_inode));
 158         BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
 159
 160         if (!sb_set_blocksize(s, BLOCK_SIZE))
 161                 goto out_bad_hblock;
 162
 163         if (!(bh = sb_bread(s, 1)))
 164                 goto out_bad_sb;
 165
 166         ms = (struct minix_super_block *) bh->b_data;
 167         sbi->s_ms = ms;
 168         sbi->s_sbh = bh;
 169         sbi->s_mount_state = ms->s_state;
 170         sbi->s_ninodes = ms->s_ninodes;
 171         sbi->s_nzones = ms->s_nzones;
 172         sbi->s_imap_blocks = ms->s_imap_blocks;
 173         sbi->s_zmap_blocks = ms->s_zmap_blocks;
 174         sbi->s_firstdatazone = ms->s_firstdatazone;
 175         sbi->s_log_zone_size = ms->s_log_zone_size;
 176         sbi->s_max_size = ms->s_max_size;
 177         s->s_magic = ms->s_magic;
 178         if (s->s_magic == MINIX_SUPER_MAGIC) {
 179                 sbi->s_version = MINIX_V1;
 180                 sbi->s_dirsize = 16;
 181                 sbi->s_namelen = 14;
 182                 sbi->s_link_max = MINIX_LINK_MAX;
 183         } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
 184                 sbi->s_version = MINIX_V1;
 185                 sbi->s_dirsize = 32;
 186                 sbi->s_namelen = 30;
 187                 sbi->s_link_max = MINIX_LINK_MAX;
 188         } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
 189                 sbi->s_version = MINIX_V2;
 190                 sbi->s_nzones = ms->s_zones;
 191                 sbi->s_dirsize = 16;
 192                 sbi->s_namelen = 14;
 193                 sbi->s_link_max = MINIX2_LINK_MAX;
 194         } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
 195                 sbi->s_version = MINIX_V2;
 196                 sbi->s_nzones = ms->s_zones;
 197                 sbi->s_dirsize = 32;
 198                 sbi->s_namelen = 30;
 199                 sbi->s_link_max = MINIX2_LINK_MAX;
 200         } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
 201                 m3s = (struct minix3_super_block *) bh->b_data;
 202                 s->s_magic = m3s->s_magic;
 203                 sbi->s_imap_blocks = m3s->s_imap_blocks;
 204                 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
 205                 sbi->s_firstdatazone = m3s->s_firstdatazone;
 206                 sbi->s_log_zone_size = m3s->s_log_zone_size;
 207                 sbi->s_max_size = m3s->s_max_size;
 208                 sbi->s_ninodes = m3s->s_ninodes;
 209                 sbi->s_nzones = m3s->s_zones;
 210                 sbi->s_dirsize = 64;
 211                 sbi->s_namelen = 60;
 212                 sbi->s_version = MINIX_V3;
 213                 sbi->s_link_max = MINIX2_LINK_MAX;
 214                 sbi->s_mount_state = MINIX_VALID_FS;
 215                 sb_set_blocksize(s, m3s->s_blocksize);
 216         } else
 217                 goto out_no_fs;
 218
 219         /*
 220          * Allocate the buffer map to keep the superblock small.
 221          */
 222         if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
 223                 goto out_illegal_sb;
 224         i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
 225         map = kzalloc(i, GFP_KERNEL);
 226         if (!map)
 227                 goto out_no_map;
 228         sbi->s_imap = &map[0];
 229         sbi->s_zmap = &map[sbi->s_imap_blocks];
 230
 231         block=2;
 232         for (i=0 ; i < sbi->s_imap_blocks ; i++) {
 233                 if (!(sbi->s_imap[i]=sb_bread(s, block)))
 234                         goto out_no_bitmap;
 235                 block++;
 236         }
 237         for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
 238                 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
 239                         goto out_no_bitmap;
 240                 block++;
 241         }
 242
 243         minix_set_bit(0,sbi->s_imap[0]->b_data);
 244         minix_set_bit(0,sbi->s_zmap[0]->b_data);
 245
 246         /* set up enough so that it can read an inode */
 247         s->s_op = &minix_sops;
 248         root_inode = minix_iget(s, MINIX_ROOT_INO);
 249         if (IS_ERR(root_inode)) {
 250                 ret = PTR_ERR(root_inode);
 251                 goto out_no_root;
 252         }
 253
 254         ret = -ENOMEM;
 255         s->s_root = d_alloc_root(root_inode);
 256         if (!s->s_root)
 257                 goto out_iput;
 258
 259         if (!(s->s_flags & MS_RDONLY)) {
 260                 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
 261                         ms->s_state &= ~MINIX_VALID_FS;
 262                 mark_buffer_dirty(bh);
 263         }
 264         if (!(sbi->s_mount_state & MINIX_VALID_FS))
 265                 printk("MINIX-fs: mounting unchecked file system, "
 266                         "running fsck is recommended\n");
 267         else if (sbi->s_mount_state & MINIX_ERROR_FS)
 268                 printk("MINIX-fs: mounting file system with errors, "
 269                         "running fsck is recommended\n");
 270         return 0;
 271
 272 out_iput:
 273         iput(root_inode);
 274         goto out_freemap;
 275
 276 out_no_root:
 277         if (!silent)
 278                 printk("MINIX-fs: get root inode failed\n");
 279         goto out_freemap;
 280
 281 out_no_bitmap:
 282         printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
 283 out_freemap:
 284         for (i = 0; i < sbi->s_imap_blocks; i++)
 285                 brelse(sbi->s_imap[i]);
 286         for (i = 0; i < sbi->s_zmap_blocks; i++)
 287                 brelse(sbi->s_zmap[i]);
 288         kfree(sbi->s_imap);
 289         goto out_release;
 290
 291 out_no_map:
 292         ret = -ENOMEM;
 293         if (!silent)
 294                 printk("MINIX-fs: can't allocate map\n");
 295         goto out_release;
 296
 297 out_illegal_sb:
 298         if (!silent)
 299                 printk("MINIX-fs: bad superblock\n");
 300         goto out_release;
 301
 302 out_no_fs:
 303         if (!silent)
 304                 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
 305                        "on device %s.\n", s->s_id);
 306 out_release:
 307         brelse(bh);
 308         goto out;
 309
 310 out_bad_hblock:
 311         printk("MINIX-fs: blocksize too small for device\n");
 312         goto out;
 313
 314 out_bad_sb:
 315         printk("MINIX-fs: unable to read superblock\n");
 316 out:
 317         s->s_fs_info = NULL;
 318         kfree(sbi);
 319         return ret;
 320 }
 321
 322 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
 323 {
 324         struct super_block *sb = dentry->d_sb;
 325         struct minix_sb_info *sbi = minix_sb(sb);
 326         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 327         buf->f_type = sb->s_magic;
 328         buf->f_bsize = sb->s_blocksize;
 329         buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
 330         buf->f_bfree = minix_count_free_blocks(sbi);
 331         buf->f_bavail = buf->f_bfree;
 332         buf->f_files = sbi->s_ninodes;
 333         buf->f_ffree = minix_count_free_inodes(sbi);
 334         buf->f_namelen = sbi->s_namelen;
 335         buf->f_fsid.val[0] = (u32)id;
 336         buf->f_fsid.val[1] = (u32)(id >> 32);
 337
 338         return 0;
 339 }
 340
 341 static int minix_get_block(struct inode *inode, sector_t block,
 342                     struct buffer_head *bh_result, int create)
 343 {
 344         if (INODE_VERSION(inode) == MINIX_V1)
 345                 return V1_minix_get_block(inode, block, bh_result, create);
 346         else
 347                 return V2_minix_get_block(inode, block, bh_result, create);
 348 }
 349
 350 static int minix_writepage(struct page *page, struct writeback_control *wbc)
 351 {
 352         return block_write_full_page(page, minix_get_block, wbc);
 353 }
 354
 355 static int minix_readpage(struct file *file, struct page *page)
 356 {
 357         return block_read_full_page(page,minix_get_block);
 358 }
 359
 360 int __minix_write_begin(struct file *file, struct address_space *mapping,
 361                         loff_t pos, unsigned len, unsigned flags,
 362                         struct page **pagep, void **fsdata)
 363 {
 364         return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
 365                                 minix_get_block);
 366 }
 367
 368 static int minix_write_begin(struct file *file, struct address_space *mapping,
 369                         loff_t pos, unsigned len, unsigned flags,
 370                         struct page **pagep, void **fsdata)
 371 {
 372         *pagep = NULL;
 373         return __minix_write_begin(file, mapping, pos, len, flags, pagep, fsdata);
 374 }
 375
 376 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
 377 {
 378         return generic_block_bmap(mapping,block,minix_get_block);
 379 }
 380
 381 static const struct address_space_operations minix_aops = {
 382         .readpage = minix_readpage,
 383         .writepage = minix_writepage,
 384         .sync_page = block_sync_page,
 385         .write_begin = minix_write_begin,
 386         .write_end = generic_write_end,
 387         .bmap = minix_bmap
 388 };
 389
 390 static const struct inode_operations minix_symlink_inode_operations = {
 391         .readlink       = generic_readlink,
 392         .follow_link    = page_follow_link_light,
 393         .put_link       = page_put_link,
 394         .getattr        = minix_getattr,
 395 };
 396
 397 void minix_set_inode(struct inode *inode, dev_t rdev)
 398 {
 399         if (S_ISREG(inode->i_mode)) {
 400                 inode->i_op = &minix_file_inode_operations;
 401                 inode->i_fop = &minix_file_operations;
 402                 inode->i_mapping->a_ops = &minix_aops;
 403         } else if (S_ISDIR(inode->i_mode)) {
 404                 inode->i_op = &minix_dir_inode_operations;
 405                 inode->i_fop = &minix_dir_operations;
 406                 inode->i_mapping->a_ops = &minix_aops;
 407         } else if (S_ISLNK(inode->i_mode)) {
 408                 inode->i_op = &minix_symlink_inode_operations;
 409                 inode->i_mapping->a_ops = &minix_aops;
 410         } else
 411                 init_special_inode(inode, inode->i_mode, rdev);
 412 }
 413
 414 /*
 415  * The minix V1 function to read an inode.
 416  */
 417 static struct inode *V1_minix_iget(struct inode *inode)
 418 {
 419         struct buffer_head * bh;
 420         struct minix_inode * raw_inode;
 421         struct minix_inode_info *minix_inode = minix_i(inode);
 422         int i;
 423
 424         raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
 425         if (!raw_inode) {
 426                 iget_failed(inode);
 427                 return ERR_PTR(-EIO);
 428         }
 429         inode->i_mode = raw_inode->i_mode;
 430         inode->i_uid = (uid_t)raw_inode->i_uid;
 431         inode->i_gid = (gid_t)raw_inode->i_gid;
 432         inode->i_nlink = raw_inode->i_nlinks;
 433         inode->i_size = raw_inode->i_size;
 434         inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
 435         inode->i_mtime.tv_nsec = 0;
 436         inode->i_atime.tv_nsec = 0;
 437         inode->i_ctime.tv_nsec = 0;
 438         inode->i_blocks = 0;
 439         for (i = 0; i < 9; i++)
 440                 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
 441         minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
 442         brelse(bh);
 443         unlock_new_inode(inode);
 444         return inode;
 445 }
 446
 447 /*
 448  * The minix V2 function to read an inode.
 449  */
 450 static struct inode *V2_minix_iget(struct inode *inode)
 451 {
 452         struct buffer_head * bh;
 453         struct minix2_inode * raw_inode;
 454         struct minix_inode_info *minix_inode = minix_i(inode);
 455         int i;
 456
 457         raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
 458         if (!raw_inode) {
 459                 iget_failed(inode);
 460                 return ERR_PTR(-EIO);
 461         }
 462         inode->i_mode = raw_inode->i_mode;
 463         inode->i_uid = (uid_t)raw_inode->i_uid;
 464         inode->i_gid = (gid_t)raw_inode->i_gid;
 465         inode->i_nlink = raw_inode->i_nlinks;
 466         inode->i_size = raw_inode->i_size;
 467         inode->i_mtime.tv_sec = raw_inode->i_mtime;
 468         inode->i_atime.tv_sec = raw_inode->i_atime;
 469         inode->i_ctime.tv_sec = raw_inode->i_ctime;
 470         inode->i_mtime.tv_nsec = 0;
 471         inode->i_atime.tv_nsec = 0;
 472         inode->i_ctime.tv_nsec = 0;
 473         inode->i_blocks = 0;
 474         for (i = 0; i < 10; i++)
 475                 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
 476         minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
 477         brelse(bh);
 478         unlock_new_inode(inode);
 479         return inode;
 480 }
 481
 482 /*
 483  * The global function to read an inode.
 484  */
 485 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
 486 {
 487         struct inode *inode;
 488
 489         inode = iget_locked(sb, ino);
 490         if (!inode)
 491                 return ERR_PTR(-ENOMEM);
 492         if (!(inode->i_state & I_NEW))
 493                 return inode;
 494
 495         if (INODE_VERSION(inode) == MINIX_V1)
 496                 return V1_minix_iget(inode);
 497         else
 498                 return V2_minix_iget(inode);
 499 }
 500
 501 /*
 502  * The minix V1 function to synchronize an inode.
 503  */
 504 static struct buffer_head * V1_minix_update_inode(struct inode * inode)
 505 {
 506         struct buffer_head * bh;
 507         struct minix_inode * raw_inode;
 508         struct minix_inode_info *minix_inode = minix_i(inode);
 509         int i;
 510
 511         raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
 512         if (!raw_inode)
 513                 return NULL;
 514         raw_inode->i_mode = inode->i_mode;
 515         raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
 516         raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
 517         raw_inode->i_nlinks = inode->i_nlink;
 518         raw_inode->i_size = inode->i_size;
 519         raw_inode->i_time = inode->i_mtime.tv_sec;
 520         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 521                 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
 522         else for (i = 0; i < 9; i++)
 523                 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
 524         mark_buffer_dirty(bh);
 525         return bh;
 526 }
 527
 528 /*
 529  * The minix V2 function to synchronize an inode.
 530  */
 531 static struct buffer_head * V2_minix_update_inode(struct inode * inode)
 532 {
 533         struct buffer_head * bh;
 534         struct minix2_inode * raw_inode;
 535         struct minix_inode_info *minix_inode = minix_i(inode);
 536         int i;
 537
 538         raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
 539         if (!raw_inode)
 540                 return NULL;
 541         raw_inode->i_mode = inode->i_mode;
 542         raw_inode->i_uid = fs_high2lowuid(inode->i_uid);
 543         raw_inode->i_gid = fs_high2lowgid(inode->i_gid);
 544         raw_inode->i_nlinks = inode->i_nlink;
 545         raw_inode->i_size = inode->i_size;
 546         raw_inode->i_mtime = inode->i_mtime.tv_sec;
 547         raw_inode->i_atime = inode->i_atime.tv_sec;
 548         raw_inode->i_ctime = inode->i_ctime.tv_sec;
 549         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 550                 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
 551         else for (i = 0; i < 10; i++)
 552                 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
 553         mark_buffer_dirty(bh);
 554         return bh;
 555 }
 556
 557 static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
 558 {
 559         int err = 0;
 560         struct buffer_head *bh;
 561
 562         if (INODE_VERSION(inode) == MINIX_V1)
 563                 bh = V1_minix_update_inode(inode);
 564         else
 565                 bh = V2_minix_update_inode(inode);
 566         if (!bh)
 567                 return -EIO;
 568         if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
 569                 sync_dirty_buffer(bh);
 570                 if (buffer_req(bh) && !buffer_uptodate(bh)) {
 571                         printk("IO error syncing minix inode [%s:%08lx]\n",
 572                                 inode->i_sb->s_id, inode->i_ino);
 573                         err = -EIO;
 574                 }
 575         }
 576         brelse (bh);
 577         return err;
 578 }
 579
 580 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 581 {
 582         struct inode *dir = dentry->d_parent->d_inode;
 583         struct super_block *sb = dir->i_sb;
 584         generic_fillattr(dentry->d_inode, stat);
 585         if (INODE_VERSION(dentry->d_inode) == MINIX_V1)
 586                 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
 587         else
 588                 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
 589         stat->blksize = sb->s_blocksize;
 590         return 0;
 591 }
 592
 593 /*
 594  * The function that is called for file truncation.
 595  */
 596 void minix_truncate(struct inode * inode)
 597 {
 598         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
 599                 return;
 600         if (INODE_VERSION(inode) == MINIX_V1)
 601                 V1_minix_truncate(inode);
 602         else
 603                 V2_minix_truncate(inode);
 604 }
 605
 606 static int minix_get_sb(struct file_system_type *fs_type,
 607         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 608 {
 609         return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super,
 610                            mnt);
 611 }
 612
 613 static struct file_system_type minix_fs_type = {
 614         .owner          = THIS_MODULE,
 615         .name           = "minix",
 616         .get_sb         = minix_get_sb,
 617         .kill_sb        = kill_block_super,
 618         .fs_flags       = FS_REQUIRES_DEV,
 619 };
 620
 621 static int __init init_minix_fs(void)
 622 {
 623         int err = init_inodecache();
 624         if (err)
 625                 goto out1;
 626         err = register_filesystem(&minix_fs_type);
 627         if (err)
 628                 goto out;
 629         return 0;
 630 out:
 631         destroy_inodecache();
 632 out1:
 633         return err;
 634 }
 635
 636 static void __exit exit_minix_fs(void)
 637 {
 638         unregister_filesystem(&minix_fs_type);
 639         destroy_inodecache();
 640 }
 641
 642 module_init(init_minix_fs)
 643 module_exit(exit_minix_fs)
 644 MODULE_LICENSE("GPL");
 645