fs/minix/inode.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  linux/fs/minix/inode.c
   4  *
   5  *  Copyright (C) 1991, 1992  Linus Torvalds
   6  *
   7  *  Copyright (C) 1996  Gertjan van Wingerde
   8  *      Minix V2 fs support.
   9  *
  10  *  Modified for 680x0 by Andreas Schwab
  11  *  Updated to filesystem version 3 by Daniel Aragones
  12  */
  13
  14 #include <linux/module.h>
  15 #include "minix.h"
  16 #include <linux/buffer_head.h>
  17 #include <linux/slab.h>
  18 #include <linux/init.h>
  19 #include <linux/highuid.h>
  20 #include <linux/vfs.h>
  21 #include <linux/writeback.h>
  22
  23 static int minix_write_inode(struct inode *inode,
  24                 struct writeback_control *wbc);
  25 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
  26 static int minix_remount (struct super_block * sb, int * flags, char * data);
  27
  28 static void minix_evict_inode(struct inode *inode)
  29 {
  30         truncate_inode_pages_final(&inode->i_data);
  31         if (!inode->i_nlink) {
  32                 inode->i_size = 0;
  33                 minix_truncate(inode);
  34         }
  35         invalidate_inode_buffers(inode);
  36         clear_inode(inode);
  37         if (!inode->i_nlink)
  38                 minix_free_inode(inode);
  39 }
  40
  41 static void minix_put_super(struct super_block *sb)
  42 {
  43         int i;
  44         struct minix_sb_info *sbi = minix_sb(sb);
  45
  46         if (!sb_rdonly(sb)) {
  47                 if (sbi->s_version != MINIX_V3)  /* s_state is now out from V3 sb */
  48                         sbi->s_ms->s_state = sbi->s_mount_state;
  49                 mark_buffer_dirty(sbi->s_sbh);
  50         }
  51         for (i = 0; i < sbi->s_imap_blocks; i++)
  52                 brelse(sbi->s_imap[i]);
  53         for (i = 0; i < sbi->s_zmap_blocks; i++)
  54                 brelse(sbi->s_zmap[i]);
  55         brelse (sbi->s_sbh);
  56         kfree(sbi->s_imap);
  57         sb->s_fs_info = NULL;
  58         kfree(sbi);
  59 }
  60
  61 static struct kmem_cache * minix_inode_cachep;
  62
  63 static struct inode *minix_alloc_inode(struct super_block *sb)
  64 {
  65         struct minix_inode_info *ei;
  66         ei = alloc_inode_sb(sb, minix_inode_cachep, GFP_KERNEL);
  67         if (!ei)
  68                 return NULL;
  69         return &ei->vfs_inode;
  70 }
  71
  72 static void minix_free_in_core_inode(struct inode *inode)
  73 {
  74         kmem_cache_free(minix_inode_cachep, minix_i(inode));
  75 }
  76
  77 static void init_once(void *foo)
  78 {
  79         struct minix_inode_info *ei = (struct minix_inode_info *) foo;
  80
  81         inode_init_once(&ei->vfs_inode);
  82 }
  83
  84 static int __init init_inodecache(void)
  85 {
  86         minix_inode_cachep = kmem_cache_create("minix_inode_cache",
  87                                              sizeof(struct minix_inode_info),
  88                                              0, (SLAB_RECLAIM_ACCOUNT|
  89                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
  90                                              init_once);
  91         if (minix_inode_cachep == NULL)
  92                 return -ENOMEM;
  93         return 0;
  94 }
  95
  96 static void destroy_inodecache(void)
  97 {
  98         /*
  99          * Make sure all delayed rcu free inodes are flushed before we
 100          * destroy cache.
 101          */
 102         rcu_barrier();
 103         kmem_cache_destroy(minix_inode_cachep);
 104 }
 105
 106 static const struct super_operations minix_sops = {
 107         .alloc_inode    = minix_alloc_inode,
 108         .free_inode     = minix_free_in_core_inode,
 109         .write_inode    = minix_write_inode,
 110         .evict_inode    = minix_evict_inode,
 111         .put_super      = minix_put_super,
 112         .statfs         = minix_statfs,
 113         .remount_fs     = minix_remount,
 114 };
 115
 116 static int minix_remount (struct super_block * sb, int * flags, char * data)
 117 {
 118         struct minix_sb_info * sbi = minix_sb(sb);
 119         struct minix_super_block * ms;
 120
 121         sync_filesystem(sb);
 122         ms = sbi->s_ms;
 123         if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
 124                 return 0;
 125         if (*flags & SB_RDONLY) {
 126                 if (ms->s_state & MINIX_VALID_FS ||
 127                     !(sbi->s_mount_state & MINIX_VALID_FS))
 128                         return 0;
 129                 /* Mounting a rw partition read-only. */
 130                 if (sbi->s_version != MINIX_V3)
 131                         ms->s_state = sbi->s_mount_state;
 132                 mark_buffer_dirty(sbi->s_sbh);
 133         } else {
 134                 /* Mount a partition which is read-only, read-write. */
 135                 if (sbi->s_version != MINIX_V3) {
 136                         sbi->s_mount_state = ms->s_state;
 137                         ms->s_state &= ~MINIX_VALID_FS;
 138                 } else {
 139                         sbi->s_mount_state = MINIX_VALID_FS;
 140                 }
 141                 mark_buffer_dirty(sbi->s_sbh);
 142
 143                 if (!(sbi->s_mount_state & MINIX_VALID_FS))
 144                         printk("MINIX-fs warning: remounting unchecked fs, "
 145                                 "running fsck is recommended\n");
 146                 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
 147                         printk("MINIX-fs warning: remounting fs with errors, "
 148                                 "running fsck is recommended\n");
 149         }
 150         return 0;
 151 }
 152
 153 static bool minix_check_superblock(struct super_block *sb)
 154 {
 155         struct minix_sb_info *sbi = minix_sb(sb);
 156
 157         if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
 158                 return false;
 159
 160         /*
 161          * s_max_size must not exceed the block mapping limitation.  This check
 162          * is only needed for V1 filesystems, since V2/V3 support an extra level
 163          * of indirect blocks which places the limit well above U32_MAX.
 164          */
 165         if (sbi->s_version == MINIX_V1 &&
 166             sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE)
 167                 return false;
 168
 169         return true;
 170 }
 171
 172 static int minix_fill_super(struct super_block *s, void *data, int silent)
 173 {
 174         struct buffer_head *bh;
 175         struct buffer_head **map;
 176         struct minix_super_block *ms;
 177         struct minix3_super_block *m3s = NULL;
 178         unsigned long i, block;
 179         struct inode *root_inode;
 180         struct minix_sb_info *sbi;
 181         int ret = -EINVAL;
 182
 183         sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
 184         if (!sbi)
 185                 return -ENOMEM;
 186         s->s_fs_info = sbi;
 187
 188         BUILD_BUG_ON(32 != sizeof (struct minix_inode));
 189         BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
 190
 191         if (!sb_set_blocksize(s, BLOCK_SIZE))
 192                 goto out_bad_hblock;
 193
 194         if (!(bh = sb_bread(s, 1)))
 195                 goto out_bad_sb;
 196
 197         ms = (struct minix_super_block *) bh->b_data;
 198         sbi->s_ms = ms;
 199         sbi->s_sbh = bh;
 200         sbi->s_mount_state = ms->s_state;
 201         sbi->s_ninodes = ms->s_ninodes;
 202         sbi->s_nzones = ms->s_nzones;
 203         sbi->s_imap_blocks = ms->s_imap_blocks;
 204         sbi->s_zmap_blocks = ms->s_zmap_blocks;
 205         sbi->s_firstdatazone = ms->s_firstdatazone;
 206         sbi->s_log_zone_size = ms->s_log_zone_size;
 207         s->s_maxbytes = ms->s_max_size;
 208         s->s_magic = ms->s_magic;
 209         if (s->s_magic == MINIX_SUPER_MAGIC) {
 210                 sbi->s_version = MINIX_V1;
 211                 sbi->s_dirsize = 16;
 212                 sbi->s_namelen = 14;
 213                 s->s_max_links = MINIX_LINK_MAX;
 214         } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
 215                 sbi->s_version = MINIX_V1;
 216                 sbi->s_dirsize = 32;
 217                 sbi->s_namelen = 30;
 218                 s->s_max_links = MINIX_LINK_MAX;
 219         } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
 220                 sbi->s_version = MINIX_V2;
 221                 sbi->s_nzones = ms->s_zones;
 222                 sbi->s_dirsize = 16;
 223                 sbi->s_namelen = 14;
 224                 s->s_max_links = MINIX2_LINK_MAX;
 225         } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
 226                 sbi->s_version = MINIX_V2;
 227                 sbi->s_nzones = ms->s_zones;
 228                 sbi->s_dirsize = 32;
 229                 sbi->s_namelen = 30;
 230                 s->s_max_links = MINIX2_LINK_MAX;
 231         } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
 232                 m3s = (struct minix3_super_block *) bh->b_data;
 233                 s->s_magic = m3s->s_magic;
 234                 sbi->s_imap_blocks = m3s->s_imap_blocks;
 235                 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
 236                 sbi->s_firstdatazone = m3s->s_firstdatazone;
 237                 sbi->s_log_zone_size = m3s->s_log_zone_size;
 238                 s->s_maxbytes = m3s->s_max_size;
 239                 sbi->s_ninodes = m3s->s_ninodes;
 240                 sbi->s_nzones = m3s->s_zones;
 241                 sbi->s_dirsize = 64;
 242                 sbi->s_namelen = 60;
 243                 sbi->s_version = MINIX_V3;
 244                 sbi->s_mount_state = MINIX_VALID_FS;
 245                 sb_set_blocksize(s, m3s->s_blocksize);
 246                 s->s_max_links = MINIX2_LINK_MAX;
 247         } else
 248                 goto out_no_fs;
 249
 250         if (!minix_check_superblock(s))
 251                 goto out_illegal_sb;
 252
 253         /*
 254          * Allocate the buffer map to keep the superblock small.
 255          */
 256         i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
 257         map = kzalloc(i, GFP_KERNEL);
 258         if (!map)
 259                 goto out_no_map;
 260         sbi->s_imap = &map[0];
 261         sbi->s_zmap = &map[sbi->s_imap_blocks];
 262
 263         block=2;
 264         for (i=0 ; i < sbi->s_imap_blocks ; i++) {
 265                 if (!(sbi->s_imap[i]=sb_bread(s, block)))
 266                         goto out_no_bitmap;
 267                 block++;
 268         }
 269         for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
 270                 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
 271                         goto out_no_bitmap;
 272                 block++;
 273         }
 274
 275         minix_set_bit(0,sbi->s_imap[0]->b_data);
 276         minix_set_bit(0,sbi->s_zmap[0]->b_data);
 277
 278         /* Apparently minix can create filesystems that allocate more blocks for
 279          * the bitmaps than needed.  We simply ignore that, but verify it didn't
 280          * create one with not enough blocks and bail out if so.
 281          */
 282         block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
 283         if (sbi->s_imap_blocks < block) {
 284                 printk("MINIX-fs: file system does not have enough "
 285                                 "imap blocks allocated.  Refusing to mount.\n");
 286                 goto out_no_bitmap;
 287         }
 288
 289         block = minix_blocks_needed(
 290                         (sbi->s_nzones - sbi->s_firstdatazone + 1),
 291                         s->s_blocksize);
 292         if (sbi->s_zmap_blocks < block) {
 293                 printk("MINIX-fs: file system does not have enough "
 294                                 "zmap blocks allocated.  Refusing to mount.\n");
 295                 goto out_no_bitmap;
 296         }
 297
 298         /* set up enough so that it can read an inode */
 299         s->s_op = &minix_sops;
 300         s->s_time_min = 0;
 301         s->s_time_max = U32_MAX;
 302         root_inode = minix_iget(s, MINIX_ROOT_INO);
 303         if (IS_ERR(root_inode)) {
 304                 ret = PTR_ERR(root_inode);
 305                 goto out_no_root;
 306         }
 307
 308         ret = -ENOMEM;
 309         s->s_root = d_make_root(root_inode);
 310         if (!s->s_root)
 311                 goto out_no_root;
 312
 313         if (!sb_rdonly(s)) {
 314                 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
 315                         ms->s_state &= ~MINIX_VALID_FS;
 316                 mark_buffer_dirty(bh);
 317         }
 318         if (!(sbi->s_mount_state & MINIX_VALID_FS))
 319                 printk("MINIX-fs: mounting unchecked file system, "
 320                         "running fsck is recommended\n");
 321         else if (sbi->s_mount_state & MINIX_ERROR_FS)
 322                 printk("MINIX-fs: mounting file system with errors, "
 323                         "running fsck is recommended\n");
 324
 325         return 0;
 326
 327 out_no_root:
 328         if (!silent)
 329                 printk("MINIX-fs: get root inode failed\n");
 330         goto out_freemap;
 331
 332 out_no_bitmap:
 333         printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
 334 out_freemap:
 335         for (i = 0; i < sbi->s_imap_blocks; i++)
 336                 brelse(sbi->s_imap[i]);
 337         for (i = 0; i < sbi->s_zmap_blocks; i++)
 338                 brelse(sbi->s_zmap[i]);
 339         kfree(sbi->s_imap);
 340         goto out_release;
 341
 342 out_no_map:
 343         ret = -ENOMEM;
 344         if (!silent)
 345                 printk("MINIX-fs: can't allocate map\n");
 346         goto out_release;
 347
 348 out_illegal_sb:
 349         if (!silent)
 350                 printk("MINIX-fs: bad superblock\n");
 351         goto out_release;
 352
 353 out_no_fs:
 354         if (!silent)
 355                 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
 356                        "on device %s.\n", s->s_id);
 357 out_release:
 358         brelse(bh);
 359         goto out;
 360
 361 out_bad_hblock:
 362         printk("MINIX-fs: blocksize too small for device\n");
 363         goto out;
 364
 365 out_bad_sb:
 366         printk("MINIX-fs: unable to read superblock\n");
 367 out:
 368         s->s_fs_info = NULL;
 369         kfree(sbi);
 370         return ret;
 371 }
 372
 373 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
 374 {
 375         struct super_block *sb = dentry->d_sb;
 376         struct minix_sb_info *sbi = minix_sb(sb);
 377         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 378         buf->f_type = sb->s_magic;
 379         buf->f_bsize = sb->s_blocksize;
 380         buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
 381         buf->f_bfree = minix_count_free_blocks(sb);
 382         buf->f_bavail = buf->f_bfree;
 383         buf->f_files = sbi->s_ninodes;
 384         buf->f_ffree = minix_count_free_inodes(sb);
 385         buf->f_namelen = sbi->s_namelen;
 386         buf->f_fsid = u64_to_fsid(id);
 387
 388         return 0;
 389 }
 390
 391 static int minix_get_block(struct inode *inode, sector_t block,
 392                     struct buffer_head *bh_result, int create)
 393 {
 394         if (INODE_VERSION(inode) == MINIX_V1)
 395                 return V1_minix_get_block(inode, block, bh_result, create);
 396         else
 397                 return V2_minix_get_block(inode, block, bh_result, create);
 398 }
 399
 400 static int minix_writepage(struct page *page, struct writeback_control *wbc)
 401 {
 402         return block_write_full_page(page, minix_get_block, wbc);
 403 }
 404
 405 static int minix_read_folio(struct file *file, struct folio *folio)
 406 {
 407         return block_read_full_folio(folio, minix_get_block);
 408 }
 409
 410 int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len)
 411 {
 412         return __block_write_begin(page, pos, len, minix_get_block);
 413 }
 414
 415 static void minix_write_failed(struct address_space *mapping, loff_t to)
 416 {
 417         struct inode *inode = mapping->host;
 418
 419         if (to > inode->i_size) {
 420                 truncate_pagecache(inode, inode->i_size);
 421                 minix_truncate(inode);
 422         }
 423 }
 424
 425 static int minix_write_begin(struct file *file, struct address_space *mapping,
 426                         loff_t pos, unsigned len,
 427                         struct page **pagep, void **fsdata)
 428 {
 429         int ret;
 430
 431         ret = block_write_begin(mapping, pos, len, pagep, minix_get_block);
 432         if (unlikely(ret))
 433                 minix_write_failed(mapping, pos + len);
 434
 435         return ret;
 436 }
 437
 438 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
 439 {
 440         return generic_block_bmap(mapping,block,minix_get_block);
 441 }
 442
 443 static const struct address_space_operations minix_aops = {
 444         .dirty_folio    = block_dirty_folio,
 445         .invalidate_folio = block_invalidate_folio,
 446         .read_folio = minix_read_folio,
 447         .writepage = minix_writepage,
 448         .write_begin = minix_write_begin,
 449         .write_end = generic_write_end,
 450         .bmap = minix_bmap,
 451         .direct_IO = noop_direct_IO
 452 };
 453
 454 static const struct inode_operations minix_symlink_inode_operations = {
 455         .get_link       = page_get_link,
 456         .getattr        = minix_getattr,
 457 };
 458
 459 void minix_set_inode(struct inode *inode, dev_t rdev)
 460 {
 461         if (S_ISREG(inode->i_mode)) {
 462                 inode->i_op = &minix_file_inode_operations;
 463                 inode->i_fop = &minix_file_operations;
 464                 inode->i_mapping->a_ops = &minix_aops;
 465         } else if (S_ISDIR(inode->i_mode)) {
 466                 inode->i_op = &minix_dir_inode_operations;
 467                 inode->i_fop = &minix_dir_operations;
 468                 inode->i_mapping->a_ops = &minix_aops;
 469         } else if (S_ISLNK(inode->i_mode)) {
 470                 inode->i_op = &minix_symlink_inode_operations;
 471                 inode_nohighmem(inode);
 472                 inode->i_mapping->a_ops = &minix_aops;
 473         } else
 474                 init_special_inode(inode, inode->i_mode, rdev);
 475 }
 476
 477 /*
 478  * The minix V1 function to read an inode.
 479  */
 480 static struct inode *V1_minix_iget(struct inode *inode)
 481 {
 482         struct buffer_head * bh;
 483         struct minix_inode * raw_inode;
 484         struct minix_inode_info *minix_inode = minix_i(inode);
 485         int i;
 486
 487         raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
 488         if (!raw_inode) {
 489                 iget_failed(inode);
 490                 return ERR_PTR(-EIO);
 491         }
 492         if (raw_inode->i_nlinks == 0) {
 493                 printk("MINIX-fs: deleted inode referenced: %lu\n",
 494                        inode->i_ino);
 495                 brelse(bh);
 496                 iget_failed(inode);
 497                 return ERR_PTR(-ESTALE);
 498         }
 499         inode->i_mode = raw_inode->i_mode;
 500         i_uid_write(inode, raw_inode->i_uid);
 501         i_gid_write(inode, raw_inode->i_gid);
 502         set_nlink(inode, raw_inode->i_nlinks);
 503         inode->i_size = raw_inode->i_size;
 504         inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time;
 505         inode->i_mtime.tv_nsec = 0;
 506         inode->i_atime.tv_nsec = 0;
 507         inode->i_ctime.tv_nsec = 0;
 508         inode->i_blocks = 0;
 509         for (i = 0; i < 9; i++)
 510                 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
 511         minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
 512         brelse(bh);
 513         unlock_new_inode(inode);
 514         return inode;
 515 }
 516
 517 /*
 518  * The minix V2 function to read an inode.
 519  */
 520 static struct inode *V2_minix_iget(struct inode *inode)
 521 {
 522         struct buffer_head * bh;
 523         struct minix2_inode * raw_inode;
 524         struct minix_inode_info *minix_inode = minix_i(inode);
 525         int i;
 526
 527         raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
 528         if (!raw_inode) {
 529                 iget_failed(inode);
 530                 return ERR_PTR(-EIO);
 531         }
 532         if (raw_inode->i_nlinks == 0) {
 533                 printk("MINIX-fs: deleted inode referenced: %lu\n",
 534                        inode->i_ino);
 535                 brelse(bh);
 536                 iget_failed(inode);
 537                 return ERR_PTR(-ESTALE);
 538         }
 539         inode->i_mode = raw_inode->i_mode;
 540         i_uid_write(inode, raw_inode->i_uid);
 541         i_gid_write(inode, raw_inode->i_gid);
 542         set_nlink(inode, raw_inode->i_nlinks);
 543         inode->i_size = raw_inode->i_size;
 544         inode->i_mtime.tv_sec = raw_inode->i_mtime;
 545         inode->i_atime.tv_sec = raw_inode->i_atime;
 546         inode->i_ctime.tv_sec = raw_inode->i_ctime;
 547         inode->i_mtime.tv_nsec = 0;
 548         inode->i_atime.tv_nsec = 0;
 549         inode->i_ctime.tv_nsec = 0;
 550         inode->i_blocks = 0;
 551         for (i = 0; i < 10; i++)
 552                 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
 553         minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
 554         brelse(bh);
 555         unlock_new_inode(inode);
 556         return inode;
 557 }
 558
 559 /*
 560  * The global function to read an inode.
 561  */
 562 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
 563 {
 564         struct inode *inode;
 565
 566         inode = iget_locked(sb, ino);
 567         if (!inode)
 568                 return ERR_PTR(-ENOMEM);
 569         if (!(inode->i_state & I_NEW))
 570                 return inode;
 571
 572         if (INODE_VERSION(inode) == MINIX_V1)
 573                 return V1_minix_iget(inode);
 574         else
 575                 return V2_minix_iget(inode);
 576 }
 577
 578 /*
 579  * The minix V1 function to synchronize an inode.
 580  */
 581 static struct buffer_head * V1_minix_update_inode(struct inode * inode)
 582 {
 583         struct buffer_head * bh;
 584         struct minix_inode * raw_inode;
 585         struct minix_inode_info *minix_inode = minix_i(inode);
 586         int i;
 587
 588         raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
 589         if (!raw_inode)
 590                 return NULL;
 591         raw_inode->i_mode = inode->i_mode;
 592         raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
 593         raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
 594         raw_inode->i_nlinks = inode->i_nlink;
 595         raw_inode->i_size = inode->i_size;
 596         raw_inode->i_time = inode->i_mtime.tv_sec;
 597         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 598                 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
 599         else for (i = 0; i < 9; i++)
 600                 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
 601         mark_buffer_dirty(bh);
 602         return bh;
 603 }
 604
 605 /*
 606  * The minix V2 function to synchronize an inode.
 607  */
 608 static struct buffer_head * V2_minix_update_inode(struct inode * inode)
 609 {
 610         struct buffer_head * bh;
 611         struct minix2_inode * raw_inode;
 612         struct minix_inode_info *minix_inode = minix_i(inode);
 613         int i;
 614
 615         raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
 616         if (!raw_inode)
 617                 return NULL;
 618         raw_inode->i_mode = inode->i_mode;
 619         raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
 620         raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
 621         raw_inode->i_nlinks = inode->i_nlink;
 622         raw_inode->i_size = inode->i_size;
 623         raw_inode->i_mtime = inode->i_mtime.tv_sec;
 624         raw_inode->i_atime = inode->i_atime.tv_sec;
 625         raw_inode->i_ctime = inode->i_ctime.tv_sec;
 626         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 627                 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
 628         else for (i = 0; i < 10; i++)
 629                 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
 630         mark_buffer_dirty(bh);
 631         return bh;
 632 }
 633
 634 static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
 635 {
 636         int err = 0;
 637         struct buffer_head *bh;
 638
 639         if (INODE_VERSION(inode) == MINIX_V1)
 640                 bh = V1_minix_update_inode(inode);
 641         else
 642                 bh = V2_minix_update_inode(inode);
 643         if (!bh)
 644                 return -EIO;
 645         if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
 646                 sync_dirty_buffer(bh);
 647                 if (buffer_req(bh) && !buffer_uptodate(bh)) {
 648                         printk("IO error syncing minix inode [%s:%08lx]\n",
 649                                 inode->i_sb->s_id, inode->i_ino);
 650                         err = -EIO;
 651                 }
 652         }
 653         brelse (bh);
 654         return err;
 655 }
 656
 657 int minix_getattr(struct user_namespace *mnt_userns, const struct path *path,
 658                   struct kstat *stat, u32 request_mask, unsigned int flags)
 659 {
 660         struct super_block *sb = path->dentry->d_sb;
 661         struct inode *inode = d_inode(path->dentry);
 662
 663         generic_fillattr(&init_user_ns, inode, stat);
 664         if (INODE_VERSION(inode) == MINIX_V1)
 665                 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
 666         else
 667                 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
 668         stat->blksize = sb->s_blocksize;
 669         return 0;
 670 }
 671
 672 /*
 673  * The function that is called for file truncation.
 674  */
 675 void minix_truncate(struct inode * inode)
 676 {
 677         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
 678                 return;
 679         if (INODE_VERSION(inode) == MINIX_V1)
 680                 V1_minix_truncate(inode);
 681         else
 682                 V2_minix_truncate(inode);
 683 }
 684
 685 static struct dentry *minix_mount(struct file_system_type *fs_type,
 686         int flags, const char *dev_name, void *data)
 687 {
 688         return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super);
 689 }
 690
 691 static struct file_system_type minix_fs_type = {
 692         .owner          = THIS_MODULE,
 693         .name           = "minix",
 694         .mount          = minix_mount,
 695         .kill_sb        = kill_block_super,
 696         .fs_flags       = FS_REQUIRES_DEV,
 697 };
 698 MODULE_ALIAS_FS("minix");
 699
 700 static int __init init_minix_fs(void)
 701 {
 702         int err = init_inodecache();
 703         if (err)
 704                 goto out1;
 705         err = register_filesystem(&minix_fs_type);
 706         if (err)
 707                 goto out;
 708         return 0;
 709 out:
 710         destroy_inodecache();
 711 out1:
 712         return err;
 713 }
 714
 715 static void __exit exit_minix_fs(void)
 716 {
 717         unregister_filesystem(&minix_fs_type);
 718         destroy_inodecache();
 719 }
 720
 721 module_init(init_minix_fs)
 722 module_exit(exit_minix_fs)
 723 MODULE_LICENSE("GPL");
 724