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 mnt_idmap *idmap, 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(&nop_mnt_idmap, 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"); 724 725