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_readpage(struct file *file, struct page *page) 406 { 407 return block_read_full_page(page,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, unsigned flags, 427 struct page **pagep, void **fsdata) 428 { 429 int ret; 430 431 ret = block_write_begin(mapping, pos, len, flags, pagep, 432 minix_get_block); 433 if (unlikely(ret)) 434 minix_write_failed(mapping, pos + len); 435 436 return ret; 437 } 438 439 static sector_t minix_bmap(struct address_space *mapping, sector_t block) 440 { 441 return generic_block_bmap(mapping,block,minix_get_block); 442 } 443 444 static const struct address_space_operations minix_aops = { 445 .dirty_folio = block_dirty_folio, 446 .invalidate_folio = block_invalidate_folio, 447 .readpage = minix_readpage, 448 .writepage = minix_writepage, 449 .write_begin = minix_write_begin, 450 .write_end = generic_write_end, 451 .bmap = minix_bmap, 452 .direct_IO = noop_direct_IO 453 }; 454 455 static const struct inode_operations minix_symlink_inode_operations = { 456 .get_link = page_get_link, 457 .getattr = minix_getattr, 458 }; 459 460 void minix_set_inode(struct inode *inode, dev_t rdev) 461 { 462 if (S_ISREG(inode->i_mode)) { 463 inode->i_op = &minix_file_inode_operations; 464 inode->i_fop = &minix_file_operations; 465 inode->i_mapping->a_ops = &minix_aops; 466 } else if (S_ISDIR(inode->i_mode)) { 467 inode->i_op = &minix_dir_inode_operations; 468 inode->i_fop = &minix_dir_operations; 469 inode->i_mapping->a_ops = &minix_aops; 470 } else if (S_ISLNK(inode->i_mode)) { 471 inode->i_op = &minix_symlink_inode_operations; 472 inode_nohighmem(inode); 473 inode->i_mapping->a_ops = &minix_aops; 474 } else 475 init_special_inode(inode, inode->i_mode, rdev); 476 } 477 478 /* 479 * The minix V1 function to read an inode. 480 */ 481 static struct inode *V1_minix_iget(struct inode *inode) 482 { 483 struct buffer_head * bh; 484 struct minix_inode * raw_inode; 485 struct minix_inode_info *minix_inode = minix_i(inode); 486 int i; 487 488 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 489 if (!raw_inode) { 490 iget_failed(inode); 491 return ERR_PTR(-EIO); 492 } 493 if (raw_inode->i_nlinks == 0) { 494 printk("MINIX-fs: deleted inode referenced: %lu\n", 495 inode->i_ino); 496 brelse(bh); 497 iget_failed(inode); 498 return ERR_PTR(-ESTALE); 499 } 500 inode->i_mode = raw_inode->i_mode; 501 i_uid_write(inode, raw_inode->i_uid); 502 i_gid_write(inode, raw_inode->i_gid); 503 set_nlink(inode, raw_inode->i_nlinks); 504 inode->i_size = raw_inode->i_size; 505 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; 506 inode->i_mtime.tv_nsec = 0; 507 inode->i_atime.tv_nsec = 0; 508 inode->i_ctime.tv_nsec = 0; 509 inode->i_blocks = 0; 510 for (i = 0; i < 9; i++) 511 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 512 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 513 brelse(bh); 514 unlock_new_inode(inode); 515 return inode; 516 } 517 518 /* 519 * The minix V2 function to read an inode. 520 */ 521 static struct inode *V2_minix_iget(struct inode *inode) 522 { 523 struct buffer_head * bh; 524 struct minix2_inode * raw_inode; 525 struct minix_inode_info *minix_inode = minix_i(inode); 526 int i; 527 528 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 529 if (!raw_inode) { 530 iget_failed(inode); 531 return ERR_PTR(-EIO); 532 } 533 if (raw_inode->i_nlinks == 0) { 534 printk("MINIX-fs: deleted inode referenced: %lu\n", 535 inode->i_ino); 536 brelse(bh); 537 iget_failed(inode); 538 return ERR_PTR(-ESTALE); 539 } 540 inode->i_mode = raw_inode->i_mode; 541 i_uid_write(inode, raw_inode->i_uid); 542 i_gid_write(inode, raw_inode->i_gid); 543 set_nlink(inode, raw_inode->i_nlinks); 544 inode->i_size = raw_inode->i_size; 545 inode->i_mtime.tv_sec = raw_inode->i_mtime; 546 inode->i_atime.tv_sec = raw_inode->i_atime; 547 inode->i_ctime.tv_sec = raw_inode->i_ctime; 548 inode->i_mtime.tv_nsec = 0; 549 inode->i_atime.tv_nsec = 0; 550 inode->i_ctime.tv_nsec = 0; 551 inode->i_blocks = 0; 552 for (i = 0; i < 10; i++) 553 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 554 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 555 brelse(bh); 556 unlock_new_inode(inode); 557 return inode; 558 } 559 560 /* 561 * The global function to read an inode. 562 */ 563 struct inode *minix_iget(struct super_block *sb, unsigned long ino) 564 { 565 struct inode *inode; 566 567 inode = iget_locked(sb, ino); 568 if (!inode) 569 return ERR_PTR(-ENOMEM); 570 if (!(inode->i_state & I_NEW)) 571 return inode; 572 573 if (INODE_VERSION(inode) == MINIX_V1) 574 return V1_minix_iget(inode); 575 else 576 return V2_minix_iget(inode); 577 } 578 579 /* 580 * The minix V1 function to synchronize an inode. 581 */ 582 static struct buffer_head * V1_minix_update_inode(struct inode * inode) 583 { 584 struct buffer_head * bh; 585 struct minix_inode * raw_inode; 586 struct minix_inode_info *minix_inode = minix_i(inode); 587 int i; 588 589 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 590 if (!raw_inode) 591 return NULL; 592 raw_inode->i_mode = inode->i_mode; 593 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode)); 594 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode)); 595 raw_inode->i_nlinks = inode->i_nlink; 596 raw_inode->i_size = inode->i_size; 597 raw_inode->i_time = inode->i_mtime.tv_sec; 598 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 599 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 600 else for (i = 0; i < 9; i++) 601 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 602 mark_buffer_dirty(bh); 603 return bh; 604 } 605 606 /* 607 * The minix V2 function to synchronize an inode. 608 */ 609 static struct buffer_head * V2_minix_update_inode(struct inode * inode) 610 { 611 struct buffer_head * bh; 612 struct minix2_inode * raw_inode; 613 struct minix_inode_info *minix_inode = minix_i(inode); 614 int i; 615 616 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 617 if (!raw_inode) 618 return NULL; 619 raw_inode->i_mode = inode->i_mode; 620 raw_inode->i_uid = fs_high2lowuid(i_uid_read(inode)); 621 raw_inode->i_gid = fs_high2lowgid(i_gid_read(inode)); 622 raw_inode->i_nlinks = inode->i_nlink; 623 raw_inode->i_size = inode->i_size; 624 raw_inode->i_mtime = inode->i_mtime.tv_sec; 625 raw_inode->i_atime = inode->i_atime.tv_sec; 626 raw_inode->i_ctime = inode->i_ctime.tv_sec; 627 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 628 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 629 else for (i = 0; i < 10; i++) 630 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 631 mark_buffer_dirty(bh); 632 return bh; 633 } 634 635 static int minix_write_inode(struct inode *inode, struct writeback_control *wbc) 636 { 637 int err = 0; 638 struct buffer_head *bh; 639 640 if (INODE_VERSION(inode) == MINIX_V1) 641 bh = V1_minix_update_inode(inode); 642 else 643 bh = V2_minix_update_inode(inode); 644 if (!bh) 645 return -EIO; 646 if (wbc->sync_mode == WB_SYNC_ALL && buffer_dirty(bh)) { 647 sync_dirty_buffer(bh); 648 if (buffer_req(bh) && !buffer_uptodate(bh)) { 649 printk("IO error syncing minix inode [%s:%08lx]\n", 650 inode->i_sb->s_id, inode->i_ino); 651 err = -EIO; 652 } 653 } 654 brelse (bh); 655 return err; 656 } 657 658 int minix_getattr(struct user_namespace *mnt_userns, const struct path *path, 659 struct kstat *stat, u32 request_mask, unsigned int flags) 660 { 661 struct super_block *sb = path->dentry->d_sb; 662 struct inode *inode = d_inode(path->dentry); 663 664 generic_fillattr(&init_user_ns, inode, stat); 665 if (INODE_VERSION(inode) == MINIX_V1) 666 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb); 667 else 668 stat->blocks = (sb->s_blocksize / 512) * V2_minix_blocks(stat->size, sb); 669 stat->blksize = sb->s_blocksize; 670 return 0; 671 } 672 673 /* 674 * The function that is called for file truncation. 675 */ 676 void minix_truncate(struct inode * inode) 677 { 678 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 679 return; 680 if (INODE_VERSION(inode) == MINIX_V1) 681 V1_minix_truncate(inode); 682 else 683 V2_minix_truncate(inode); 684 } 685 686 static struct dentry *minix_mount(struct file_system_type *fs_type, 687 int flags, const char *dev_name, void *data) 688 { 689 return mount_bdev(fs_type, flags, dev_name, data, minix_fill_super); 690 } 691 692 static struct file_system_type minix_fs_type = { 693 .owner = THIS_MODULE, 694 .name = "minix", 695 .mount = minix_mount, 696 .kill_sb = kill_block_super, 697 .fs_flags = FS_REQUIRES_DEV, 698 }; 699 MODULE_ALIAS_FS("minix"); 700 701 static int __init init_minix_fs(void) 702 { 703 int err = init_inodecache(); 704 if (err) 705 goto out1; 706 err = register_filesystem(&minix_fs_type); 707 if (err) 708 goto out; 709 return 0; 710 out: 711 destroy_inodecache(); 712 out1: 713 return err; 714 } 715 716 static void __exit exit_minix_fs(void) 717 { 718 unregister_filesystem(&minix_fs_type); 719 destroy_inodecache(); 720 } 721 722 module_init(init_minix_fs) 723 module_exit(exit_minix_fs) 724 MODULE_LICENSE("GPL"); 725 726