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