fs/affs/super.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/fs/affs/inode.c
   4  *
   5  *  (c) 1996  Hans-Joachim Widmaier - Rewritten
   6  *
   7  *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
   8  *
   9  *  (C) 1992  Eric Youngdale Modified for ISO 9660 filesystem.
  10  *
  11  *  (C) 1991  Linus Torvalds - minix filesystem
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/statfs.h>
  17 #include <linux/parser.h>
  18 #include <linux/magic.h>
  19 #include <linux/sched.h>
  20 #include <linux/cred.h>
  21 #include <linux/slab.h>
  22 #include <linux/writeback.h>
  23 #include <linux/blkdev.h>
  24 #include <linux/seq_file.h>
  25 #include <linux/iversion.h>
  26 #include "affs.h"
  27
  28 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);
  29 static int affs_show_options(struct seq_file *m, struct dentry *root);
  30 static int affs_remount (struct super_block *sb, int *flags, char *data);
  31
  32 static void
  33 affs_commit_super(struct super_block *sb, int wait)
  34 {
  35         struct affs_sb_info *sbi = AFFS_SB(sb);
  36         struct buffer_head *bh = sbi->s_root_bh;
  37         struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh);
  38
  39         lock_buffer(bh);
  40         affs_secs_to_datestamp(ktime_get_real_seconds(), &tail->disk_change);
  41         affs_fix_checksum(sb, bh);
  42         unlock_buffer(bh);
  43
  44         mark_buffer_dirty(bh);
  45         if (wait)
  46                 sync_dirty_buffer(bh);
  47 }
  48
  49 static void
  50 affs_put_super(struct super_block *sb)
  51 {
  52         struct affs_sb_info *sbi = AFFS_SB(sb);
  53         pr_debug("%s()\n", __func__);
  54
  55         cancel_delayed_work_sync(&sbi->sb_work);
  56 }
  57
  58 static int
  59 affs_sync_fs(struct super_block *sb, int wait)
  60 {
  61         affs_commit_super(sb, wait);
  62         return 0;
  63 }
  64
  65 static void flush_superblock(struct work_struct *work)
  66 {
  67         struct affs_sb_info *sbi;
  68         struct super_block *sb;
  69
  70         sbi = container_of(work, struct affs_sb_info, sb_work.work);
  71         sb = sbi->sb;
  72
  73         spin_lock(&sbi->work_lock);
  74         sbi->work_queued = 0;
  75         spin_unlock(&sbi->work_lock);
  76
  77         affs_commit_super(sb, 1);
  78 }
  79
  80 void affs_mark_sb_dirty(struct super_block *sb)
  81 {
  82         struct affs_sb_info *sbi = AFFS_SB(sb);
  83         unsigned long delay;
  84
  85         if (sb_rdonly(sb))
  86                return;
  87
  88         spin_lock(&sbi->work_lock);
  89         if (!sbi->work_queued) {
  90                delay = msecs_to_jiffies(dirty_writeback_interval * 10);
  91                queue_delayed_work(system_long_wq, &sbi->sb_work, delay);
  92                sbi->work_queued = 1;
  93         }
  94         spin_unlock(&sbi->work_lock);
  95 }
  96
  97 static struct kmem_cache * affs_inode_cachep;
  98
  99 static struct inode *affs_alloc_inode(struct super_block *sb)
 100 {
 101         struct affs_inode_info *i;
 102
 103         i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL);
 104         if (!i)
 105                 return NULL;
 106
 107         inode_set_iversion(&i->vfs_inode, 1);
 108         i->i_lc = NULL;
 109         i->i_ext_bh = NULL;
 110         i->i_pa_cnt = 0;
 111
 112         return &i->vfs_inode;
 113 }
 114
 115 static void affs_free_inode(struct inode *inode)
 116 {
 117         kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
 118 }
 119
 120 static void init_once(void *foo)
 121 {
 122         struct affs_inode_info *ei = (struct affs_inode_info *) foo;
 123
 124         sema_init(&ei->i_link_lock, 1);
 125         sema_init(&ei->i_ext_lock, 1);
 126         inode_init_once(&ei->vfs_inode);
 127 }
 128
 129 static int __init init_inodecache(void)
 130 {
 131         affs_inode_cachep = kmem_cache_create("affs_inode_cache",
 132                                              sizeof(struct affs_inode_info),
 133                                              0, (SLAB_RECLAIM_ACCOUNT|
 134                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
 135                                              init_once);
 136         if (affs_inode_cachep == NULL)
 137                 return -ENOMEM;
 138         return 0;
 139 }
 140
 141 static void destroy_inodecache(void)
 142 {
 143         /*
 144          * Make sure all delayed rcu free inodes are flushed before we
 145          * destroy cache.
 146          */
 147         rcu_barrier();
 148         kmem_cache_destroy(affs_inode_cachep);
 149 }
 150
 151 static const struct super_operations affs_sops = {
 152         .alloc_inode    = affs_alloc_inode,
 153         .free_inode     = affs_free_inode,
 154         .write_inode    = affs_write_inode,
 155         .evict_inode    = affs_evict_inode,
 156         .put_super      = affs_put_super,
 157         .sync_fs        = affs_sync_fs,
 158         .statfs         = affs_statfs,
 159         .remount_fs     = affs_remount,
 160         .show_options   = affs_show_options,
 161 };
 162
 163 enum {
 164         Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect,
 165         Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
 166         Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
 167 };
 168
 169 static const match_table_t tokens = {
 170         {Opt_bs, "bs=%u"},
 171         {Opt_mode, "mode=%o"},
 172         {Opt_mufs, "mufs"},
 173         {Opt_notruncate, "nofilenametruncate"},
 174         {Opt_prefix, "prefix=%s"},
 175         {Opt_protect, "protect"},
 176         {Opt_reserved, "reserved=%u"},
 177         {Opt_root, "root=%u"},
 178         {Opt_setgid, "setgid=%u"},
 179         {Opt_setuid, "setuid=%u"},
 180         {Opt_verbose, "verbose"},
 181         {Opt_volume, "volume=%s"},
 182         {Opt_ignore, "grpquota"},
 183         {Opt_ignore, "noquota"},
 184         {Opt_ignore, "quota"},
 185         {Opt_ignore, "usrquota"},
 186         {Opt_err, NULL},
 187 };
 188
 189 static int
 190 parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root,
 191                 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
 192 {
 193         char *p;
 194         substring_t args[MAX_OPT_ARGS];
 195
 196         /* Fill in defaults */
 197
 198         *uid        = current_uid();
 199         *gid        = current_gid();
 200         *reserved   = 2;
 201         *root       = -1;
 202         *blocksize  = -1;
 203         volume[0]   = ':';
 204         volume[1]   = 0;
 205         *mount_opts = 0;
 206         if (!options)
 207                 return 1;
 208
 209         while ((p = strsep(&options, ",")) != NULL) {
 210                 int token, n, option;
 211                 if (!*p)
 212                         continue;
 213
 214                 token = match_token(p, tokens, args);
 215                 switch (token) {
 216                 case Opt_bs:
 217                         if (match_int(&args[0], &n))
 218                                 return 0;
 219                         if (n != 512 && n != 1024 && n != 2048
 220                             && n != 4096) {
 221                                 pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
 222                                 return 0;
 223                         }
 224                         *blocksize = n;
 225                         break;
 226                 case Opt_mode:
 227                         if (match_octal(&args[0], &option))
 228                                 return 0;
 229                         *mode = option & 0777;
 230                         affs_set_opt(*mount_opts, SF_SETMODE);
 231                         break;
 232                 case Opt_mufs:
 233                         affs_set_opt(*mount_opts, SF_MUFS);
 234                         break;
 235                 case Opt_notruncate:
 236                         affs_set_opt(*mount_opts, SF_NO_TRUNCATE);
 237                         break;
 238                 case Opt_prefix:
 239                         kfree(*prefix);
 240                         *prefix = match_strdup(&args[0]);
 241                         if (!*prefix)
 242                                 return 0;
 243                         affs_set_opt(*mount_opts, SF_PREFIX);
 244                         break;
 245                 case Opt_protect:
 246                         affs_set_opt(*mount_opts, SF_IMMUTABLE);
 247                         break;
 248                 case Opt_reserved:
 249                         if (match_int(&args[0], reserved))
 250                                 return 0;
 251                         break;
 252                 case Opt_root:
 253                         if (match_int(&args[0], root))
 254                                 return 0;
 255                         break;
 256                 case Opt_setgid:
 257                         if (match_int(&args[0], &option))
 258                                 return 0;
 259                         *gid = make_kgid(current_user_ns(), option);
 260                         if (!gid_valid(*gid))
 261                                 return 0;
 262                         affs_set_opt(*mount_opts, SF_SETGID);
 263                         break;
 264                 case Opt_setuid:
 265                         if (match_int(&args[0], &option))
 266                                 return 0;
 267                         *uid = make_kuid(current_user_ns(), option);
 268                         if (!uid_valid(*uid))
 269                                 return 0;
 270                         affs_set_opt(*mount_opts, SF_SETUID);
 271                         break;
 272                 case Opt_verbose:
 273                         affs_set_opt(*mount_opts, SF_VERBOSE);
 274                         break;
 275                 case Opt_volume: {
 276                         char *vol = match_strdup(&args[0]);
 277                         if (!vol)
 278                                 return 0;
 279                         strlcpy(volume, vol, 32);
 280                         kfree(vol);
 281                         break;
 282                 }
 283                 case Opt_ignore:
 284                         /* Silently ignore the quota options */
 285                         break;
 286                 default:
 287                         pr_warn("Unrecognized mount option \"%s\" or missing value\n",
 288                                 p);
 289                         return 0;
 290                 }
 291         }
 292         return 1;
 293 }
 294
 295 static int affs_show_options(struct seq_file *m, struct dentry *root)
 296 {
 297         struct super_block *sb = root->d_sb;
 298         struct affs_sb_info *sbi = AFFS_SB(sb);
 299
 300         if (sb->s_blocksize)
 301                 seq_printf(m, ",bs=%lu", sb->s_blocksize);
 302         if (affs_test_opt(sbi->s_flags, SF_SETMODE))
 303                 seq_printf(m, ",mode=%o", sbi->s_mode);
 304         if (affs_test_opt(sbi->s_flags, SF_MUFS))
 305                 seq_puts(m, ",mufs");
 306         if (affs_test_opt(sbi->s_flags, SF_NO_TRUNCATE))
 307                 seq_puts(m, ",nofilenametruncate");
 308         if (affs_test_opt(sbi->s_flags, SF_PREFIX))
 309                 seq_printf(m, ",prefix=%s", sbi->s_prefix);
 310         if (affs_test_opt(sbi->s_flags, SF_IMMUTABLE))
 311                 seq_puts(m, ",protect");
 312         if (sbi->s_reserved != 2)
 313                 seq_printf(m, ",reserved=%u", sbi->s_reserved);
 314         if (sbi->s_root_block != (sbi->s_reserved + sbi->s_partition_size - 1) / 2)
 315                 seq_printf(m, ",root=%u", sbi->s_root_block);
 316         if (affs_test_opt(sbi->s_flags, SF_SETGID))
 317                 seq_printf(m, ",setgid=%u",
 318                            from_kgid_munged(&init_user_ns, sbi->s_gid));
 319         if (affs_test_opt(sbi->s_flags, SF_SETUID))
 320                 seq_printf(m, ",setuid=%u",
 321                            from_kuid_munged(&init_user_ns, sbi->s_uid));
 322         if (affs_test_opt(sbi->s_flags, SF_VERBOSE))
 323                 seq_puts(m, ",verbose");
 324         if (sbi->s_volume[0])
 325                 seq_printf(m, ",volume=%s", sbi->s_volume);
 326         return 0;
 327 }
 328
 329 /* This function definitely needs to be split up. Some fine day I'll
 330  * hopefully have the guts to do so. Until then: sorry for the mess.
 331  */
 332
 333 static int affs_fill_super(struct super_block *sb, void *data, int silent)
 334 {
 335         struct affs_sb_info     *sbi;
 336         struct buffer_head      *root_bh = NULL;
 337         struct buffer_head      *boot_bh;
 338         struct inode            *root_inode = NULL;
 339         s32                      root_block;
 340         int                      size, blocksize;
 341         u32                      chksum;
 342         int                      num_bm;
 343         int                      i, j;
 344         kuid_t                   uid;
 345         kgid_t                   gid;
 346         int                      reserved;
 347         unsigned long            mount_flags;
 348         int                      tmp_flags;     /* fix remount prototype... */
 349         u8                       sig[4];
 350         int                      ret;
 351
 352         pr_debug("read_super(%s)\n", data ? (const char *)data : "no options");
 353
 354         sb->s_magic             = AFFS_SUPER_MAGIC;
 355         sb->s_op                = &affs_sops;
 356         sb->s_flags |= SB_NODIRATIME;
 357
 358         sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL);
 359         if (!sbi)
 360                 return -ENOMEM;
 361
 362         sb->s_fs_info = sbi;
 363         sbi->sb = sb;
 364         mutex_init(&sbi->s_bmlock);
 365         spin_lock_init(&sbi->symlink_lock);
 366         spin_lock_init(&sbi->work_lock);
 367         INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock);
 368
 369         if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
 370                                 &blocksize,&sbi->s_prefix,
 371                                 sbi->s_volume, &mount_flags)) {
 372                 pr_err("Error parsing options\n");
 373                 return -EINVAL;
 374         }
 375         /* N.B. after this point s_prefix must be released */
 376
 377         sbi->s_flags   = mount_flags;
 378         sbi->s_mode    = i;
 379         sbi->s_uid     = uid;
 380         sbi->s_gid     = gid;
 381         sbi->s_reserved= reserved;
 382
 383         /* Get the size of the device in 512-byte blocks.
 384          * If we later see that the partition uses bigger
 385          * blocks, we will have to change it.
 386          */
 387
 388         size = i_size_read(sb->s_bdev->bd_inode) >> 9;
 389         pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size);
 390
 391         affs_set_blocksize(sb, PAGE_SIZE);
 392         /* Try to find root block. Its location depends on the block size. */
 393
 394         i = bdev_logical_block_size(sb->s_bdev);
 395         j = PAGE_SIZE;
 396         if (blocksize > 0) {
 397                 i = j = blocksize;
 398                 size = size / (blocksize / 512);
 399         }
 400
 401         for (blocksize = i; blocksize <= j; blocksize <<= 1, size >>= 1) {
 402                 sbi->s_root_block = root_block;
 403                 if (root_block < 0)
 404                         sbi->s_root_block = (reserved + size - 1) / 2;
 405                 pr_debug("setting blocksize to %d\n", blocksize);
 406                 affs_set_blocksize(sb, blocksize);
 407                 sbi->s_partition_size = size;
 408
 409                 /* The root block location that was calculated above is not
 410                  * correct if the partition size is an odd number of 512-
 411                  * byte blocks, which will be rounded down to a number of
 412                  * 1024-byte blocks, and if there were an even number of
 413                  * reserved blocks. Ideally, all partition checkers should
 414                  * report the real number of blocks of the real blocksize,
 415                  * but since this just cannot be done, we have to try to
 416                  * find the root block anyways. In the above case, it is one
 417                  * block behind the calculated one. So we check this one, too.
 418                  */
 419                 for (num_bm = 0; num_bm < 2; num_bm++) {
 420                         pr_debug("Dev %s, trying root=%u, bs=%d, "
 421                                 "size=%d, reserved=%d\n",
 422                                 sb->s_id,
 423                                 sbi->s_root_block + num_bm,
 424                                 blocksize, size, reserved);
 425                         root_bh = affs_bread(sb, sbi->s_root_block + num_bm);
 426                         if (!root_bh)
 427                                 continue;
 428                         if (!affs_checksum_block(sb, root_bh) &&
 429                             be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
 430                             be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
 431                                 sbi->s_hashsize    = blocksize / 4 - 56;
 432                                 sbi->s_root_block += num_bm;
 433                                 goto got_root;
 434                         }
 435                         affs_brelse(root_bh);
 436                         root_bh = NULL;
 437                 }
 438         }
 439         if (!silent)
 440                 pr_err("No valid root block on device %s\n", sb->s_id);
 441         return -EINVAL;
 442
 443         /* N.B. after this point bh must be released */
 444 got_root:
 445         /* Keep super block in cache */
 446         sbi->s_root_bh = root_bh;
 447         root_block = sbi->s_root_block;
 448
 449         /* Find out which kind of FS we have */
 450         boot_bh = sb_bread(sb, 0);
 451         if (!boot_bh) {
 452                 pr_err("Cannot read boot block\n");
 453                 return -EINVAL;
 454         }
 455         memcpy(sig, boot_bh->b_data, 4);
 456         brelse(boot_bh);
 457         chksum = be32_to_cpu(*(__be32 *)sig);
 458
 459         /* Dircache filesystems are compatible with non-dircache ones
 460          * when reading. As long as they aren't supported, writing is
 461          * not recommended.
 462          */
 463         if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
 464              || chksum == MUFS_DCOFS) && !sb_rdonly(sb)) {
 465                 pr_notice("Dircache FS - mounting %s read only\n", sb->s_id);
 466                 sb->s_flags |= SB_RDONLY;
 467         }
 468         switch (chksum) {
 469         case MUFS_FS:
 470         case MUFS_INTLFFS:
 471         case MUFS_DCFFS:
 472                 affs_set_opt(sbi->s_flags, SF_MUFS);
 473                 /* fall thru */
 474         case FS_INTLFFS:
 475         case FS_DCFFS:
 476                 affs_set_opt(sbi->s_flags, SF_INTL);
 477                 break;
 478         case MUFS_FFS:
 479                 affs_set_opt(sbi->s_flags, SF_MUFS);
 480                 break;
 481         case FS_FFS:
 482                 break;
 483         case MUFS_OFS:
 484                 affs_set_opt(sbi->s_flags, SF_MUFS);
 485                 /* fall through */
 486         case FS_OFS:
 487                 affs_set_opt(sbi->s_flags, SF_OFS);
 488                 sb->s_flags |= SB_NOEXEC;
 489                 break;
 490         case MUFS_DCOFS:
 491         case MUFS_INTLOFS:
 492                 affs_set_opt(sbi->s_flags, SF_MUFS);
 493                 /* fall through */
 494         case FS_DCOFS:
 495         case FS_INTLOFS:
 496                 affs_set_opt(sbi->s_flags, SF_INTL);
 497                 affs_set_opt(sbi->s_flags, SF_OFS);
 498                 sb->s_flags |= SB_NOEXEC;
 499                 break;
 500         default:
 501                 pr_err("Unknown filesystem on device %s: %08X\n",
 502                        sb->s_id, chksum);
 503                 return -EINVAL;
 504         }
 505
 506         if (affs_test_opt(mount_flags, SF_VERBOSE)) {
 507                 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];
 508                 pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
 509                         len > 31 ? 31 : len,
 510                         AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
 511                         sig, sig[3] + '0', blocksize);
 512         }
 513
 514         sb->s_flags |= SB_NODEV | SB_NOSUID;
 515
 516         sbi->s_data_blksize = sb->s_blocksize;
 517         if (affs_test_opt(sbi->s_flags, SF_OFS))
 518                 sbi->s_data_blksize -= 24;
 519
 520         tmp_flags = sb->s_flags;
 521         ret = affs_init_bitmap(sb, &tmp_flags);
 522         if (ret)
 523                 return ret;
 524         sb->s_flags = tmp_flags;
 525
 526         /* set up enough so that it can read an inode */
 527
 528         root_inode = affs_iget(sb, root_block);
 529         if (IS_ERR(root_inode))
 530                 return PTR_ERR(root_inode);
 531
 532         if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL))
 533                 sb->s_d_op = &affs_intl_dentry_operations;
 534         else
 535                 sb->s_d_op = &affs_dentry_operations;
 536
 537         sb->s_root = d_make_root(root_inode);
 538         if (!sb->s_root) {
 539                 pr_err("AFFS: Get root inode failed\n");
 540                 return -ENOMEM;
 541         }
 542
 543         sb->s_export_op = &affs_export_ops;
 544         pr_debug("s_flags=%lX\n", sb->s_flags);
 545         return 0;
 546 }
 547
 548 static int
 549 affs_remount(struct super_block *sb, int *flags, char *data)
 550 {
 551         struct affs_sb_info     *sbi = AFFS_SB(sb);
 552         int                      blocksize;
 553         kuid_t                   uid;
 554         kgid_t                   gid;
 555         int                      mode;
 556         int                      reserved;
 557         int                      root_block;
 558         unsigned long            mount_flags;
 559         int                      res = 0;
 560         char                    *new_opts;
 561         char                     volume[32];
 562         char                    *prefix = NULL;
 563
 564         new_opts = kstrdup(data, GFP_KERNEL);
 565         if (data && !new_opts)
 566                 return -ENOMEM;
 567
 568         pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data);
 569
 570         sync_filesystem(sb);
 571         *flags |= SB_NODIRATIME;
 572
 573         memcpy(volume, sbi->s_volume, 32);
 574         if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block,
 575                            &blocksize, &prefix, volume,
 576                            &mount_flags)) {
 577                 kfree(prefix);
 578                 kfree(new_opts);
 579                 return -EINVAL;
 580         }
 581
 582         flush_delayed_work(&sbi->sb_work);
 583
 584         sbi->s_flags = mount_flags;
 585         sbi->s_mode  = mode;
 586         sbi->s_uid   = uid;
 587         sbi->s_gid   = gid;
 588         /* protect against readers */
 589         spin_lock(&sbi->symlink_lock);
 590         if (prefix) {
 591                 kfree(sbi->s_prefix);
 592                 sbi->s_prefix = prefix;
 593         }
 594         memcpy(sbi->s_volume, volume, 32);
 595         spin_unlock(&sbi->symlink_lock);
 596
 597         if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
 598                 return 0;
 599
 600         if (*flags & SB_RDONLY)
 601                 affs_free_bitmap(sb);
 602         else
 603                 res = affs_init_bitmap(sb, flags);
 604
 605         return res;
 606 }
 607
 608 static int
 609 affs_statfs(struct dentry *dentry, struct kstatfs *buf)
 610 {
 611         struct super_block *sb = dentry->d_sb;
 612         int              free;
 613         u64              id = huge_encode_dev(sb->s_bdev->bd_dev);
 614
 615         pr_debug("%s() partsize=%d, reserved=%d\n",
 616                  __func__, AFFS_SB(sb)->s_partition_size,
 617                  AFFS_SB(sb)->s_reserved);
 618
 619         free          = affs_count_free_blocks(sb);
 620         buf->f_type    = AFFS_SUPER_MAGIC;
 621         buf->f_bsize   = sb->s_blocksize;
 622         buf->f_blocks  = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
 623         buf->f_bfree   = free;
 624         buf->f_bavail  = free;
 625         buf->f_fsid.val[0] = (u32)id;
 626         buf->f_fsid.val[1] = (u32)(id >> 32);
 627         buf->f_namelen = AFFSNAMEMAX;
 628         return 0;
 629 }
 630
 631 static struct dentry *affs_mount(struct file_system_type *fs_type,
 632         int flags, const char *dev_name, void *data)
 633 {
 634         return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super);
 635 }
 636
 637 static void affs_kill_sb(struct super_block *sb)
 638 {
 639         struct affs_sb_info *sbi = AFFS_SB(sb);
 640         kill_block_super(sb);
 641         if (sbi) {
 642                 affs_free_bitmap(sb);
 643                 affs_brelse(sbi->s_root_bh);
 644                 kfree(sbi->s_prefix);
 645                 mutex_destroy(&sbi->s_bmlock);
 646                 kfree(sbi);
 647         }
 648 }
 649
 650 static struct file_system_type affs_fs_type = {
 651         .owner          = THIS_MODULE,
 652         .name           = "affs",
 653         .mount          = affs_mount,
 654         .kill_sb        = affs_kill_sb,
 655         .fs_flags       = FS_REQUIRES_DEV,
 656 };
 657 MODULE_ALIAS_FS("affs");
 658
 659 static int __init init_affs_fs(void)
 660 {
 661         int err = init_inodecache();
 662         if (err)
 663                 goto out1;
 664         err = register_filesystem(&affs_fs_type);
 665         if (err)
 666                 goto out;
 667         return 0;
 668 out:
 669         destroy_inodecache();
 670 out1:
 671         return err;
 672 }
 673
 674 static void __exit exit_affs_fs(void)
 675 {
 676         unregister_filesystem(&affs_fs_type);
 677         destroy_inodecache();
 678 }
 679
 680 MODULE_DESCRIPTION("Amiga filesystem support for Linux");
 681 MODULE_LICENSE("GPL");
 682
 683 module_init(init_affs_fs)
 684 module_exit(exit_affs_fs)