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/mpage.h>
  21 #include <linux/vfs.h>
  22 #include <linux/writeback.h>
  23 #include <linux/fs_context.h>
  24
  25 static int minix_write_inode(struct inode *inode,
  26                 struct writeback_control *wbc);
  27 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf);
  28
  29 static void minix_evict_inode(struct inode *inode)
  30 {
  31         truncate_inode_pages_final(&inode->i_data);
  32         if (!inode->i_nlink) {
  33                 inode->i_size = 0;
  34                 minix_truncate(inode);
  35         }
  36         invalidate_inode_buffers(inode);
  37         clear_inode(inode);
  38         if (!inode->i_nlink)
  39                 minix_free_inode(inode);
  40 }
  41
  42 static void minix_put_super(struct super_block *sb)
  43 {
  44         int i;
  45         struct minix_sb_info *sbi = minix_sb(sb);
  46
  47         if (!sb_rdonly(sb)) {
  48                 if (sbi->s_version != MINIX_V3)  /* s_state is now out from V3 sb */
  49                         sbi->s_ms->s_state = sbi->s_mount_state;
  50                 mark_buffer_dirty(sbi->s_sbh);
  51         }
  52         for (i = 0; i < sbi->s_imap_blocks; i++)
  53                 brelse(sbi->s_imap[i]);
  54         for (i = 0; i < sbi->s_zmap_blocks; i++)
  55                 brelse(sbi->s_zmap[i]);
  56         brelse (sbi->s_sbh);
  57         kfree(sbi->s_imap);
  58         sb->s_fs_info = NULL;
  59         kfree(sbi);
  60 }
  61
  62 static struct kmem_cache * minix_inode_cachep;
  63
  64 static struct inode *minix_alloc_inode(struct super_block *sb)
  65 {
  66         struct minix_inode_info *ei;
  67         ei = alloc_inode_sb(sb, minix_inode_cachep, GFP_KERNEL);
  68         if (!ei)
  69                 return NULL;
  70         return &ei->vfs_inode;
  71 }
  72
  73 static void minix_free_in_core_inode(struct inode *inode)
  74 {
  75         kmem_cache_free(minix_inode_cachep, minix_i(inode));
  76 }
  77
  78 static void init_once(void *foo)
  79 {
  80         struct minix_inode_info *ei = (struct minix_inode_info *) foo;
  81
  82         inode_init_once(&ei->vfs_inode);
  83 }
  84
  85 static int __init init_inodecache(void)
  86 {
  87         minix_inode_cachep = kmem_cache_create("minix_inode_cache",
  88                                              sizeof(struct minix_inode_info),
  89                                              0, (SLAB_RECLAIM_ACCOUNT|
  90                                                 SLAB_ACCOUNT),
  91                                              init_once);
  92         if (minix_inode_cachep == NULL)
  93                 return -ENOMEM;
  94         return 0;
  95 }
  96
  97 static void destroy_inodecache(void)
  98 {
  99         /*
 100          * Make sure all delayed rcu free inodes are flushed before we
 101          * destroy cache.
 102          */
 103         rcu_barrier();
 104         kmem_cache_destroy(minix_inode_cachep);
 105 }
 106
 107 static const struct super_operations minix_sops = {
 108         .alloc_inode    = minix_alloc_inode,
 109         .free_inode     = minix_free_in_core_inode,
 110         .write_inode    = minix_write_inode,
 111         .evict_inode    = minix_evict_inode,
 112         .put_super      = minix_put_super,
 113         .statfs         = minix_statfs,
 114 };
 115
 116 static int minix_reconfigure(struct fs_context *fc)
 117 {
 118         struct minix_super_block * ms;
 119         struct super_block *sb = fc->root->d_sb;
 120         struct minix_sb_info * sbi = sb->s_fs_info;
 121
 122         sync_filesystem(sb);
 123         ms = sbi->s_ms;
 124         if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb))
 125                 return 0;
 126         if (fc->sb_flags & SB_RDONLY) {
 127                 if (ms->s_state & MINIX_VALID_FS ||
 128                     !(sbi->s_mount_state & MINIX_VALID_FS))
 129                         return 0;
 130                 /* Mounting a rw partition read-only. */
 131                 if (sbi->s_version != MINIX_V3)
 132                         ms->s_state = sbi->s_mount_state;
 133                 mark_buffer_dirty(sbi->s_sbh);
 134         } else {
 135                 /* Mount a partition which is read-only, read-write. */
 136                 if (sbi->s_version != MINIX_V3) {
 137                         sbi->s_mount_state = ms->s_state;
 138                         ms->s_state &= ~MINIX_VALID_FS;
 139                 } else {
 140                         sbi->s_mount_state = MINIX_VALID_FS;
 141                 }
 142                 mark_buffer_dirty(sbi->s_sbh);
 143
 144                 if (!(sbi->s_mount_state & MINIX_VALID_FS))
 145                         printk("MINIX-fs warning: remounting unchecked fs, "
 146                                 "running fsck is recommended\n");
 147                 else if ((sbi->s_mount_state & MINIX_ERROR_FS))
 148                         printk("MINIX-fs warning: remounting fs with errors, "
 149                                 "running fsck is recommended\n");
 150         }
 151         return 0;
 152 }
 153
 154 static bool minix_check_superblock(struct super_block *sb)
 155 {
 156         struct minix_sb_info *sbi = minix_sb(sb);
 157
 158         if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0)
 159                 return false;
 160
 161         /*
 162          * s_max_size must not exceed the block mapping limitation.  This check
 163          * is only needed for V1 filesystems, since V2/V3 support an extra level
 164          * of indirect blocks which places the limit well above U32_MAX.
 165          */
 166         if (sbi->s_version == MINIX_V1 &&
 167             sb->s_maxbytes > (7 + 512 + 512*512) * BLOCK_SIZE)
 168                 return false;
 169
 170         return true;
 171 }
 172
 173 static int minix_fill_super(struct super_block *s, struct fs_context *fc)
 174 {
 175         struct buffer_head *bh;
 176         struct buffer_head **map;
 177         struct minix_super_block *ms;
 178         struct minix3_super_block *m3s = NULL;
 179         unsigned long i, block;
 180         struct inode *root_inode;
 181         struct minix_sb_info *sbi;
 182         int ret = -EINVAL;
 183         int silent = fc->sb_flags & SB_SILENT;
 184
 185         sbi = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL);
 186         if (!sbi)
 187                 return -ENOMEM;
 188         s->s_fs_info = sbi;
 189
 190         BUILD_BUG_ON(32 != sizeof (struct minix_inode));
 191         BUILD_BUG_ON(64 != sizeof(struct minix2_inode));
 192
 193         if (!sb_set_blocksize(s, BLOCK_SIZE))
 194                 goto out_bad_hblock;
 195
 196         if (!(bh = sb_bread(s, 1)))
 197                 goto out_bad_sb;
 198
 199         ms = (struct minix_super_block *) bh->b_data;
 200         sbi->s_ms = ms;
 201         sbi->s_sbh = bh;
 202         sbi->s_mount_state = ms->s_state;
 203         sbi->s_ninodes = ms->s_ninodes;
 204         sbi->s_nzones = ms->s_nzones;
 205         sbi->s_imap_blocks = ms->s_imap_blocks;
 206         sbi->s_zmap_blocks = ms->s_zmap_blocks;
 207         sbi->s_firstdatazone = ms->s_firstdatazone;
 208         sbi->s_log_zone_size = ms->s_log_zone_size;
 209         s->s_maxbytes = ms->s_max_size;
 210         s->s_magic = ms->s_magic;
 211         if (s->s_magic == MINIX_SUPER_MAGIC) {
 212                 sbi->s_version = MINIX_V1;
 213                 sbi->s_dirsize = 16;
 214                 sbi->s_namelen = 14;
 215                 s->s_max_links = MINIX_LINK_MAX;
 216         } else if (s->s_magic == MINIX_SUPER_MAGIC2) {
 217                 sbi->s_version = MINIX_V1;
 218                 sbi->s_dirsize = 32;
 219                 sbi->s_namelen = 30;
 220                 s->s_max_links = MINIX_LINK_MAX;
 221         } else if (s->s_magic == MINIX2_SUPER_MAGIC) {
 222                 sbi->s_version = MINIX_V2;
 223                 sbi->s_nzones = ms->s_zones;
 224                 sbi->s_dirsize = 16;
 225                 sbi->s_namelen = 14;
 226                 s->s_max_links = MINIX2_LINK_MAX;
 227         } else if (s->s_magic == MINIX2_SUPER_MAGIC2) {
 228                 sbi->s_version = MINIX_V2;
 229                 sbi->s_nzones = ms->s_zones;
 230                 sbi->s_dirsize = 32;
 231                 sbi->s_namelen = 30;
 232                 s->s_max_links = MINIX2_LINK_MAX;
 233         } else if ( *(__u16 *)(bh->b_data + 24) == MINIX3_SUPER_MAGIC) {
 234                 m3s = (struct minix3_super_block *) bh->b_data;
 235                 s->s_magic = m3s->s_magic;
 236                 sbi->s_imap_blocks = m3s->s_imap_blocks;
 237                 sbi->s_zmap_blocks = m3s->s_zmap_blocks;
 238                 sbi->s_firstdatazone = m3s->s_firstdatazone;
 239                 sbi->s_log_zone_size = m3s->s_log_zone_size;
 240                 s->s_maxbytes = m3s->s_max_size;
 241                 sbi->s_ninodes = m3s->s_ninodes;
 242                 sbi->s_nzones = m3s->s_zones;
 243                 sbi->s_dirsize = 64;
 244                 sbi->s_namelen = 60;
 245                 sbi->s_version = MINIX_V3;
 246                 sbi->s_mount_state = MINIX_VALID_FS;
 247                 sb_set_blocksize(s, m3s->s_blocksize);
 248                 s->s_max_links = MINIX2_LINK_MAX;
 249         } else
 250                 goto out_no_fs;
 251
 252         if (!minix_check_superblock(s))
 253                 goto out_illegal_sb;
 254
 255         /*
 256          * Allocate the buffer map to keep the superblock small.
 257          */
 258         i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh);
 259         map = kzalloc(i, GFP_KERNEL);
 260         if (!map)
 261                 goto out_no_map;
 262         sbi->s_imap = &map[0];
 263         sbi->s_zmap = &map[sbi->s_imap_blocks];
 264
 265         block=2;
 266         for (i=0 ; i < sbi->s_imap_blocks ; i++) {
 267                 if (!(sbi->s_imap[i]=sb_bread(s, block)))
 268                         goto out_no_bitmap;
 269                 block++;
 270         }
 271         for (i=0 ; i < sbi->s_zmap_blocks ; i++) {
 272                 if (!(sbi->s_zmap[i]=sb_bread(s, block)))
 273                         goto out_no_bitmap;
 274                 block++;
 275         }
 276
 277         minix_set_bit(0,sbi->s_imap[0]->b_data);
 278         minix_set_bit(0,sbi->s_zmap[0]->b_data);
 279
 280         /* Apparently minix can create filesystems that allocate more blocks for
 281          * the bitmaps than needed.  We simply ignore that, but verify it didn't
 282          * create one with not enough blocks and bail out if so.
 283          */
 284         block = minix_blocks_needed(sbi->s_ninodes, s->s_blocksize);
 285         if (sbi->s_imap_blocks < block) {
 286                 printk("MINIX-fs: file system does not have enough "
 287                                 "imap blocks allocated.  Refusing to mount.\n");
 288                 goto out_no_bitmap;
 289         }
 290
 291         block = minix_blocks_needed(
 292                         (sbi->s_nzones - sbi->s_firstdatazone + 1),
 293                         s->s_blocksize);
 294         if (sbi->s_zmap_blocks < block) {
 295                 printk("MINIX-fs: file system does not have enough "
 296                                 "zmap blocks allocated.  Refusing to mount.\n");
 297                 goto out_no_bitmap;
 298         }
 299
 300         /* set up enough so that it can read an inode */
 301         s->s_op = &minix_sops;
 302         s->s_time_min = 0;
 303         s->s_time_max = U32_MAX;
 304         root_inode = minix_iget(s, MINIX_ROOT_INO);
 305         if (IS_ERR(root_inode)) {
 306                 ret = PTR_ERR(root_inode);
 307                 goto out_no_root;
 308         }
 309
 310         ret = -ENOMEM;
 311         s->s_root = d_make_root(root_inode);
 312         if (!s->s_root)
 313                 goto out_no_root;
 314
 315         if (!sb_rdonly(s)) {
 316                 if (sbi->s_version != MINIX_V3) /* s_state is now out from V3 sb */
 317                         ms->s_state &= ~MINIX_VALID_FS;
 318                 mark_buffer_dirty(bh);
 319         }
 320         if (!(sbi->s_mount_state & MINIX_VALID_FS))
 321                 printk("MINIX-fs: mounting unchecked file system, "
 322                         "running fsck is recommended\n");
 323         else if (sbi->s_mount_state & MINIX_ERROR_FS)
 324                 printk("MINIX-fs: mounting file system with errors, "
 325                         "running fsck is recommended\n");
 326
 327         return 0;
 328
 329 out_no_root:
 330         if (!silent)
 331                 printk("MINIX-fs: get root inode failed\n");
 332         goto out_freemap;
 333
 334 out_no_bitmap:
 335         printk("MINIX-fs: bad superblock or unable to read bitmaps\n");
 336 out_freemap:
 337         for (i = 0; i < sbi->s_imap_blocks; i++)
 338                 brelse(sbi->s_imap[i]);
 339         for (i = 0; i < sbi->s_zmap_blocks; i++)
 340                 brelse(sbi->s_zmap[i]);
 341         kfree(sbi->s_imap);
 342         goto out_release;
 343
 344 out_no_map:
 345         ret = -ENOMEM;
 346         if (!silent)
 347                 printk("MINIX-fs: can't allocate map\n");
 348         goto out_release;
 349
 350 out_illegal_sb:
 351         if (!silent)
 352                 printk("MINIX-fs: bad superblock\n");
 353         goto out_release;
 354
 355 out_no_fs:
 356         if (!silent)
 357                 printk("VFS: Can't find a Minix filesystem V1 | V2 | V3 "
 358                        "on device %s.\n", s->s_id);
 359 out_release:
 360         brelse(bh);
 361         goto out;
 362
 363 out_bad_hblock:
 364         printk("MINIX-fs: blocksize too small for device\n");
 365         goto out;
 366
 367 out_bad_sb:
 368         printk("MINIX-fs: unable to read superblock\n");
 369 out:
 370         s->s_fs_info = NULL;
 371         kfree(sbi);
 372         return ret;
 373 }
 374
 375 static int minix_get_tree(struct fs_context *fc)
 376 {
 377          return get_tree_bdev(fc, minix_fill_super);
 378 }
 379
 380 static const struct fs_context_operations minix_context_ops = {
 381         .get_tree       = minix_get_tree,
 382         .reconfigure    = minix_reconfigure,
 383 };
 384
 385 static int minix_init_fs_context(struct fs_context *fc)
 386 {
 387         fc->ops = &minix_context_ops;
 388
 389         return 0;
 390 }
 391
 392 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf)
 393 {
 394         struct super_block *sb = dentry->d_sb;
 395         struct minix_sb_info *sbi = minix_sb(sb);
 396         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 397         buf->f_type = sb->s_magic;
 398         buf->f_bsize = sb->s_blocksize;
 399         buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size;
 400         buf->f_bfree = minix_count_free_blocks(sb);
 401         buf->f_bavail = buf->f_bfree;
 402         buf->f_files = sbi->s_ninodes;
 403         buf->f_ffree = minix_count_free_inodes(sb);
 404         buf->f_namelen = sbi->s_namelen;
 405         buf->f_fsid = u64_to_fsid(id);
 406
 407         return 0;
 408 }
 409
 410 static int minix_get_block(struct inode *inode, sector_t block,
 411                     struct buffer_head *bh_result, int create)
 412 {
 413         if (INODE_VERSION(inode) == MINIX_V1)
 414                 return V1_minix_get_block(inode, block, bh_result, create);
 415         else
 416                 return V2_minix_get_block(inode, block, bh_result, create);
 417 }
 418
 419 static int minix_writepages(struct address_space *mapping,
 420                 struct writeback_control *wbc)
 421 {
 422         return mpage_writepages(mapping, wbc, minix_get_block);
 423 }
 424
 425 static int minix_read_folio(struct file *file, struct folio *folio)
 426 {
 427         return block_read_full_folio(folio, minix_get_block);
 428 }
 429
 430 int minix_prepare_chunk(struct folio *folio, loff_t pos, unsigned len)
 431 {
 432         return __block_write_begin(folio, pos, len, minix_get_block);
 433 }
 434
 435 static void minix_write_failed(struct address_space *mapping, loff_t to)
 436 {
 437         struct inode *inode = mapping->host;
 438
 439         if (to > inode->i_size) {
 440                 truncate_pagecache(inode, inode->i_size);
 441                 minix_truncate(inode);
 442         }
 443 }
 444
 445 static int minix_write_begin(struct file *file, struct address_space *mapping,
 446                         loff_t pos, unsigned len,
 447                         struct folio **foliop, void **fsdata)
 448 {
 449         int ret;
 450
 451         ret = block_write_begin(mapping, pos, len, foliop, minix_get_block);
 452         if (unlikely(ret))
 453                 minix_write_failed(mapping, pos + len);
 454
 455         return ret;
 456 }
 457
 458 static sector_t minix_bmap(struct address_space *mapping, sector_t block)
 459 {
 460         return generic_block_bmap(mapping,block,minix_get_block);
 461 }
 462
 463 static const struct address_space_operations minix_aops = {
 464         .dirty_folio    = block_dirty_folio,
 465         .invalidate_folio = block_invalidate_folio,
 466         .read_folio = minix_read_folio,
 467         .writepages = minix_writepages,
 468         .write_begin = minix_write_begin,
 469         .write_end = generic_write_end,
 470         .migrate_folio = buffer_migrate_folio,
 471         .bmap = minix_bmap,
 472         .direct_IO = noop_direct_IO
 473 };
 474
 475 static const struct inode_operations minix_symlink_inode_operations = {
 476         .get_link       = page_get_link,
 477         .getattr        = minix_getattr,
 478 };
 479
 480 void minix_set_inode(struct inode *inode, dev_t rdev)
 481 {
 482         if (S_ISREG(inode->i_mode)) {
 483                 inode->i_op = &minix_file_inode_operations;
 484                 inode->i_fop = &minix_file_operations;
 485                 inode->i_mapping->a_ops = &minix_aops;
 486         } else if (S_ISDIR(inode->i_mode)) {
 487                 inode->i_op = &minix_dir_inode_operations;
 488                 inode->i_fop = &minix_dir_operations;
 489                 inode->i_mapping->a_ops = &minix_aops;
 490         } else if (S_ISLNK(inode->i_mode)) {
 491                 inode->i_op = &minix_symlink_inode_operations;
 492                 inode_nohighmem(inode);
 493                 inode->i_mapping->a_ops = &minix_aops;
 494         } else
 495                 init_special_inode(inode, inode->i_mode, rdev);
 496 }
 497
 498 /*
 499  * The minix V1 function to read an inode.
 500  */
 501 static struct inode *V1_minix_iget(struct inode *inode)
 502 {
 503         struct buffer_head * bh;
 504         struct minix_inode * raw_inode;
 505         struct minix_inode_info *minix_inode = minix_i(inode);
 506         int i;
 507
 508         raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
 509         if (!raw_inode) {
 510                 iget_failed(inode);
 511                 return ERR_PTR(-EIO);
 512         }
 513         if (raw_inode->i_nlinks == 0) {
 514                 printk("MINIX-fs: deleted inode referenced: %lu\n",
 515                        inode->i_ino);
 516                 brelse(bh);
 517                 iget_failed(inode);
 518                 return ERR_PTR(-ESTALE);
 519         }
 520         inode->i_mode = raw_inode->i_mode;
 521         i_uid_write(inode, raw_inode->i_uid);
 522         i_gid_write(inode, raw_inode->i_gid);
 523         set_nlink(inode, raw_inode->i_nlinks);
 524         inode->i_size = raw_inode->i_size;
 525         inode_set_mtime_to_ts(inode,
 526                               inode_set_atime_to_ts(inode, inode_set_ctime(inode, raw_inode->i_time, 0)));
 527         inode->i_blocks = 0;
 528         for (i = 0; i < 9; i++)
 529                 minix_inode->u.i1_data[i] = raw_inode->i_zone[i];
 530         minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
 531         brelse(bh);
 532         unlock_new_inode(inode);
 533         return inode;
 534 }
 535
 536 /*
 537  * The minix V2 function to read an inode.
 538  */
 539 static struct inode *V2_minix_iget(struct inode *inode)
 540 {
 541         struct buffer_head * bh;
 542         struct minix2_inode * raw_inode;
 543         struct minix_inode_info *minix_inode = minix_i(inode);
 544         int i;
 545
 546         raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
 547         if (!raw_inode) {
 548                 iget_failed(inode);
 549                 return ERR_PTR(-EIO);
 550         }
 551         if (raw_inode->i_nlinks == 0) {
 552                 printk("MINIX-fs: deleted inode referenced: %lu\n",
 553                        inode->i_ino);
 554                 brelse(bh);
 555                 iget_failed(inode);
 556                 return ERR_PTR(-ESTALE);
 557         }
 558         inode->i_mode = raw_inode->i_mode;
 559         i_uid_write(inode, raw_inode->i_uid);
 560         i_gid_write(inode, raw_inode->i_gid);
 561         set_nlink(inode, raw_inode->i_nlinks);
 562         inode->i_size = raw_inode->i_size;
 563         inode_set_mtime(inode, raw_inode->i_mtime, 0);
 564         inode_set_atime(inode, raw_inode->i_atime, 0);
 565         inode_set_ctime(inode, raw_inode->i_ctime, 0);
 566         inode->i_blocks = 0;
 567         for (i = 0; i < 10; i++)
 568                 minix_inode->u.i2_data[i] = raw_inode->i_zone[i];
 569         minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0]));
 570         brelse(bh);
 571         unlock_new_inode(inode);
 572         return inode;
 573 }
 574
 575 /*
 576  * The global function to read an inode.
 577  */
 578 struct inode *minix_iget(struct super_block *sb, unsigned long ino)
 579 {
 580         struct inode *inode;
 581
 582         inode = iget_locked(sb, ino);
 583         if (!inode)
 584                 return ERR_PTR(-ENOMEM);
 585         if (!(inode->i_state & I_NEW))
 586                 return inode;
 587
 588         if (INODE_VERSION(inode) == MINIX_V1)
 589                 return V1_minix_iget(inode);
 590         else
 591                 return V2_minix_iget(inode);
 592 }
 593
 594 /*
 595  * The minix V1 function to synchronize an inode.
 596  */
 597 static struct buffer_head * V1_minix_update_inode(struct inode * inode)
 598 {
 599         struct buffer_head * bh;
 600         struct minix_inode * raw_inode;
 601         struct minix_inode_info *minix_inode = minix_i(inode);
 602         int i;
 603
 604         raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
 605         if (!raw_inode)
 606                 return NULL;
 607         raw_inode->i_mode = inode->i_mode;
 608         raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
 609         raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
 610         raw_inode->i_nlinks = inode->i_nlink;
 611         raw_inode->i_size = inode->i_size;
 612         raw_inode->i_time = inode_get_mtime_sec(inode);
 613         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 614                 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
 615         else for (i = 0; i < 9; i++)
 616                 raw_inode->i_zone[i] = minix_inode->u.i1_data[i];
 617         mark_buffer_dirty(bh);
 618         return bh;
 619 }
 620
 621 /*
 622  * The minix V2 function to synchronize an inode.
 623  */
 624 static struct buffer_head * V2_minix_update_inode(struct inode * inode)
 625 {
 626         struct buffer_head * bh;
 627         struct minix2_inode * raw_inode;
 628         struct minix_inode_info *minix_inode = minix_i(inode);
 629         int i;
 630
 631         raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
 632         if (!raw_inode)
 633                 return NULL;
 634         raw_inode->i_mode = inode->i_mode;
 635         raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode));
 636         raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode));
 637         raw_inode->i_nlinks = inode->i_nlink;
 638         raw_inode->i_size = inode->i_size;
 639         raw_inode->i_mtime = inode_get_mtime_sec(inode);
 640         raw_inode->i_atime = inode_get_atime_sec(inode);
 641         raw_inode->i_ctime = inode_get_ctime_sec(inode);
 642         if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 643                 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev);
 644         else for (i = 0; i < 10; i++)
 645                 raw_inode->i_zone[i] = minix_inode->u.i2_data[i];
 646         mark_buffer_dirty(bh);
 647         return bh;
 648 }
 649
 650 static int minix_write_inode(struct inode *inode, struct writeback_control *wbc)
 651 {
 652         int err = 0;
 653         struct buffer_head *bh;
 654
 655         if (INODE_VERSION(inode) == MINIX_V1)
 656                 bh = V1_minix_update_inode(inode);
 657         else
 658                 bh = V2_minix_update_inode(inode);
 659         if (!bh)
 660                 return -EIO;
 661         if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) {
 662                 sync_dirty_buffer(bh);
 663                 if (buffer_req(bh) && !buffer_uptodate(bh)) {
 664                         printk("IO error syncing minix inode [%s:%08lx]\n",
 665                                 inode->i_sb->s_id, inode->i_ino);
 666                         err = -EIO;
 667                 }
 668         }
 669         brelse (bh);
 670         return err;
 671 }
 672
 673 int minix_getattr(struct mnt_idmap *idmap, const struct path *path,
 674                   struct kstat *stat, u32 request_mask, unsigned int flags)
 675 {
 676         struct super_block *sb = path->dentry->d_sb;
 677         struct inode *inode = d_inode(path->dentry);
 678
 679         generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
 680         if (INODE_VERSION(inode) == MINIX_V1)
 681                 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
 682         else
 683                 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb);
 684         stat->blksize = sb->s_blocksize;
 685         return 0;
 686 }
 687
 688 /*
 689  * The function that is called for file truncation.
 690  */
 691 void minix_truncate(struct inode * inode)
 692 {
 693         if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)))
 694                 return;
 695         if (INODE_VERSION(inode) == MINIX_V1)
 696                 V1_minix_truncate(inode);
 697         else
 698                 V2_minix_truncate(inode);
 699 }
 700
 701 static struct file_system_type minix_fs_type = {
 702         .owner                  = THIS_MODULE,
 703         .name                   = "minix",
 704         .kill_sb                = kill_block_super,
 705         .fs_flags               = FS_REQUIRES_DEV,
 706         .init_fs_context        = minix_init_fs_context,
 707 };
 708 MODULE_ALIAS_FS("minix");
 709
 710 static int __init init_minix_fs(void)
 711 {
 712         int err = init_inodecache();
 713         if (err)
 714                 goto out1;
 715         err = register_filesystem(&minix_fs_type);
 716         if (err)
 717                 goto out;
 718         return 0;
 719 out:
 720         destroy_inodecache();
 721 out1:
 722         return err;
 723 }
 724
 725 static void __exit exit_minix_fs(void)
 726 {
 727         unregister_filesystem(&minix_fs_type);
 728         destroy_inodecache();
 729 }
 730
 731 module_init(init_minix_fs)
 732 module_exit(exit_minix_fs)
 733 MODULE_DESCRIPTION("Minix file system");
 734 MODULE_LICENSE("GPL");
 735