1 /* 2 * linux/fs/minix/inode.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * Copyright (C) 1996 Gertjan van Wingerde (gertjan@cs.vu.nl) 7 * Minix V2 fs support. 8 * 9 * Modified for 680x0 by Andreas Schwab 10 */ 11 12 #include <linux/module.h> 13 #include "minix.h" 14 #include <linux/buffer_head.h> 15 #include <linux/slab.h> 16 #include <linux/init.h> 17 #include <linux/highuid.h> 18 #include <linux/vfs.h> 19 20 static void minix_read_inode(struct inode * inode); 21 static int minix_write_inode(struct inode * inode, int wait); 22 static int minix_statfs(struct super_block *sb, struct kstatfs *buf); 23 static int minix_remount (struct super_block * sb, int * flags, char * data); 24 25 static void minix_delete_inode(struct inode *inode) 26 { 27 truncate_inode_pages(&inode->i_data, 0); 28 inode->i_size = 0; 29 minix_truncate(inode); 30 minix_free_inode(inode); 31 } 32 33 static void minix_put_super(struct super_block *sb) 34 { 35 int i; 36 struct minix_sb_info *sbi = minix_sb(sb); 37 38 if (!(sb->s_flags & MS_RDONLY)) { 39 sbi->s_ms->s_state = sbi->s_mount_state; 40 mark_buffer_dirty(sbi->s_sbh); 41 } 42 for (i = 0; i < sbi->s_imap_blocks; i++) 43 brelse(sbi->s_imap[i]); 44 for (i = 0; i < sbi->s_zmap_blocks; i++) 45 brelse(sbi->s_zmap[i]); 46 brelse (sbi->s_sbh); 47 kfree(sbi->s_imap); 48 sb->s_fs_info = NULL; 49 kfree(sbi); 50 51 return; 52 } 53 54 static kmem_cache_t * minix_inode_cachep; 55 56 static struct inode *minix_alloc_inode(struct super_block *sb) 57 { 58 struct minix_inode_info *ei; 59 ei = (struct minix_inode_info *)kmem_cache_alloc(minix_inode_cachep, SLAB_KERNEL); 60 if (!ei) 61 return NULL; 62 return &ei->vfs_inode; 63 } 64 65 static void minix_destroy_inode(struct inode *inode) 66 { 67 kmem_cache_free(minix_inode_cachep, minix_i(inode)); 68 } 69 70 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) 71 { 72 struct minix_inode_info *ei = (struct minix_inode_info *) foo; 73 74 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 75 SLAB_CTOR_CONSTRUCTOR) 76 inode_init_once(&ei->vfs_inode); 77 } 78 79 static int init_inodecache(void) 80 { 81 minix_inode_cachep = kmem_cache_create("minix_inode_cache", 82 sizeof(struct minix_inode_info), 83 0, SLAB_RECLAIM_ACCOUNT, 84 init_once, NULL); 85 if (minix_inode_cachep == NULL) 86 return -ENOMEM; 87 return 0; 88 } 89 90 static void destroy_inodecache(void) 91 { 92 if (kmem_cache_destroy(minix_inode_cachep)) 93 printk(KERN_INFO "minix_inode_cache: not all structures were freed\n"); 94 } 95 96 static struct super_operations minix_sops = { 97 .alloc_inode = minix_alloc_inode, 98 .destroy_inode = minix_destroy_inode, 99 .read_inode = minix_read_inode, 100 .write_inode = minix_write_inode, 101 .delete_inode = minix_delete_inode, 102 .put_super = minix_put_super, 103 .statfs = minix_statfs, 104 .remount_fs = minix_remount, 105 }; 106 107 static int minix_remount (struct super_block * sb, int * flags, char * data) 108 { 109 struct minix_sb_info * sbi = minix_sb(sb); 110 struct minix_super_block * ms; 111 112 ms = sbi->s_ms; 113 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 114 return 0; 115 if (*flags & MS_RDONLY) { 116 if (ms->s_state & MINIX_VALID_FS || 117 !(sbi->s_mount_state & MINIX_VALID_FS)) 118 return 0; 119 /* Mounting a rw partition read-only. */ 120 ms->s_state = sbi->s_mount_state; 121 mark_buffer_dirty(sbi->s_sbh); 122 } else { 123 /* Mount a partition which is read-only, read-write. */ 124 sbi->s_mount_state = ms->s_state; 125 ms->s_state &= ~MINIX_VALID_FS; 126 mark_buffer_dirty(sbi->s_sbh); 127 128 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 129 printk ("MINIX-fs warning: remounting unchecked fs, " 130 "running fsck is recommended.\n"); 131 else if ((sbi->s_mount_state & MINIX_ERROR_FS)) 132 printk ("MINIX-fs warning: remounting fs with errors, " 133 "running fsck is recommended.\n"); 134 } 135 return 0; 136 } 137 138 static int minix_fill_super(struct super_block *s, void *data, int silent) 139 { 140 struct buffer_head *bh; 141 struct buffer_head **map; 142 struct minix_super_block *ms; 143 int i, block; 144 struct inode *root_inode; 145 struct minix_sb_info *sbi; 146 147 sbi = kmalloc(sizeof(struct minix_sb_info), GFP_KERNEL); 148 if (!sbi) 149 return -ENOMEM; 150 s->s_fs_info = sbi; 151 memset(sbi, 0, sizeof(struct minix_sb_info)); 152 153 /* N.B. These should be compile-time tests. 154 Unfortunately that is impossible. */ 155 if (32 != sizeof (struct minix_inode)) 156 panic("bad V1 i-node size"); 157 if (64 != sizeof(struct minix2_inode)) 158 panic("bad V2 i-node size"); 159 160 if (!sb_set_blocksize(s, BLOCK_SIZE)) 161 goto out_bad_hblock; 162 163 if (!(bh = sb_bread(s, 1))) 164 goto out_bad_sb; 165 166 ms = (struct minix_super_block *) bh->b_data; 167 sbi->s_ms = ms; 168 sbi->s_sbh = bh; 169 sbi->s_mount_state = ms->s_state; 170 sbi->s_ninodes = ms->s_ninodes; 171 sbi->s_nzones = ms->s_nzones; 172 sbi->s_imap_blocks = ms->s_imap_blocks; 173 sbi->s_zmap_blocks = ms->s_zmap_blocks; 174 sbi->s_firstdatazone = ms->s_firstdatazone; 175 sbi->s_log_zone_size = ms->s_log_zone_size; 176 sbi->s_max_size = ms->s_max_size; 177 s->s_magic = ms->s_magic; 178 if (s->s_magic == MINIX_SUPER_MAGIC) { 179 sbi->s_version = MINIX_V1; 180 sbi->s_dirsize = 16; 181 sbi->s_namelen = 14; 182 sbi->s_link_max = MINIX_LINK_MAX; 183 } else if (s->s_magic == MINIX_SUPER_MAGIC2) { 184 sbi->s_version = MINIX_V1; 185 sbi->s_dirsize = 32; 186 sbi->s_namelen = 30; 187 sbi->s_link_max = MINIX_LINK_MAX; 188 } else if (s->s_magic == MINIX2_SUPER_MAGIC) { 189 sbi->s_version = MINIX_V2; 190 sbi->s_nzones = ms->s_zones; 191 sbi->s_dirsize = 16; 192 sbi->s_namelen = 14; 193 sbi->s_link_max = MINIX2_LINK_MAX; 194 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { 195 sbi->s_version = MINIX_V2; 196 sbi->s_nzones = ms->s_zones; 197 sbi->s_dirsize = 32; 198 sbi->s_namelen = 30; 199 sbi->s_link_max = MINIX2_LINK_MAX; 200 } else 201 goto out_no_fs; 202 203 /* 204 * Allocate the buffer map to keep the superblock small. 205 */ 206 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 207 map = kmalloc(i, GFP_KERNEL); 208 if (!map) 209 goto out_no_map; 210 memset(map, 0, i); 211 sbi->s_imap = &map[0]; 212 sbi->s_zmap = &map[sbi->s_imap_blocks]; 213 214 block=2; 215 for (i=0 ; i < sbi->s_imap_blocks ; i++) { 216 if (!(sbi->s_imap[i]=sb_bread(s, block))) 217 goto out_no_bitmap; 218 block++; 219 } 220 for (i=0 ; i < sbi->s_zmap_blocks ; i++) { 221 if (!(sbi->s_zmap[i]=sb_bread(s, block))) 222 goto out_no_bitmap; 223 block++; 224 } 225 226 minix_set_bit(0,sbi->s_imap[0]->b_data); 227 minix_set_bit(0,sbi->s_zmap[0]->b_data); 228 229 /* set up enough so that it can read an inode */ 230 s->s_op = &minix_sops; 231 root_inode = iget(s, MINIX_ROOT_INO); 232 if (!root_inode || is_bad_inode(root_inode)) 233 goto out_no_root; 234 235 s->s_root = d_alloc_root(root_inode); 236 if (!s->s_root) 237 goto out_iput; 238 239 if (!NO_TRUNCATE) 240 s->s_root->d_op = &minix_dentry_operations; 241 242 if (!(s->s_flags & MS_RDONLY)) { 243 ms->s_state &= ~MINIX_VALID_FS; 244 mark_buffer_dirty(bh); 245 } 246 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 247 printk ("MINIX-fs: mounting unchecked file system, " 248 "running fsck is recommended.\n"); 249 else if (sbi->s_mount_state & MINIX_ERROR_FS) 250 printk ("MINIX-fs: mounting file system with errors, " 251 "running fsck is recommended.\n"); 252 return 0; 253 254 out_iput: 255 iput(root_inode); 256 goto out_freemap; 257 258 out_no_root: 259 if (!silent) 260 printk("MINIX-fs: get root inode failed\n"); 261 goto out_freemap; 262 263 out_no_bitmap: 264 printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); 265 out_freemap: 266 for (i = 0; i < sbi->s_imap_blocks; i++) 267 brelse(sbi->s_imap[i]); 268 for (i = 0; i < sbi->s_zmap_blocks; i++) 269 brelse(sbi->s_zmap[i]); 270 kfree(sbi->s_imap); 271 goto out_release; 272 273 out_no_map: 274 if (!silent) 275 printk ("MINIX-fs: can't allocate map\n"); 276 goto out_release; 277 278 out_no_fs: 279 if (!silent) 280 printk("VFS: Can't find a Minix or Minix V2 filesystem on device " 281 "%s.\n", s->s_id); 282 out_release: 283 brelse(bh); 284 goto out; 285 286 out_bad_hblock: 287 printk("MINIX-fs: blocksize too small for device.\n"); 288 goto out; 289 290 out_bad_sb: 291 printk("MINIX-fs: unable to read superblock\n"); 292 out: 293 s->s_fs_info = NULL; 294 kfree(sbi); 295 return -EINVAL; 296 } 297 298 static int minix_statfs(struct super_block *sb, struct kstatfs *buf) 299 { 300 struct minix_sb_info *sbi = minix_sb(sb); 301 buf->f_type = sb->s_magic; 302 buf->f_bsize = sb->s_blocksize; 303 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; 304 buf->f_bfree = minix_count_free_blocks(sbi); 305 buf->f_bavail = buf->f_bfree; 306 buf->f_files = sbi->s_ninodes; 307 buf->f_ffree = minix_count_free_inodes(sbi); 308 buf->f_namelen = sbi->s_namelen; 309 return 0; 310 } 311 312 static int minix_get_block(struct inode *inode, sector_t block, 313 struct buffer_head *bh_result, int create) 314 { 315 if (INODE_VERSION(inode) == MINIX_V1) 316 return V1_minix_get_block(inode, block, bh_result, create); 317 else 318 return V2_minix_get_block(inode, block, bh_result, create); 319 } 320 321 static int minix_writepage(struct page *page, struct writeback_control *wbc) 322 { 323 return block_write_full_page(page, minix_get_block, wbc); 324 } 325 static int minix_readpage(struct file *file, struct page *page) 326 { 327 return block_read_full_page(page,minix_get_block); 328 } 329 static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) 330 { 331 return block_prepare_write(page,from,to,minix_get_block); 332 } 333 static sector_t minix_bmap(struct address_space *mapping, sector_t block) 334 { 335 return generic_block_bmap(mapping,block,minix_get_block); 336 } 337 static struct address_space_operations minix_aops = { 338 .readpage = minix_readpage, 339 .writepage = minix_writepage, 340 .sync_page = block_sync_page, 341 .prepare_write = minix_prepare_write, 342 .commit_write = generic_commit_write, 343 .bmap = minix_bmap 344 }; 345 346 static struct inode_operations minix_symlink_inode_operations = { 347 .readlink = generic_readlink, 348 .follow_link = page_follow_link_light, 349 .put_link = page_put_link, 350 .getattr = minix_getattr, 351 }; 352 353 void minix_set_inode(struct inode *inode, dev_t rdev) 354 { 355 if (S_ISREG(inode->i_mode)) { 356 inode->i_op = &minix_file_inode_operations; 357 inode->i_fop = &minix_file_operations; 358 inode->i_mapping->a_ops = &minix_aops; 359 } else if (S_ISDIR(inode->i_mode)) { 360 inode->i_op = &minix_dir_inode_operations; 361 inode->i_fop = &minix_dir_operations; 362 inode->i_mapping->a_ops = &minix_aops; 363 } else if (S_ISLNK(inode->i_mode)) { 364 inode->i_op = &minix_symlink_inode_operations; 365 inode->i_mapping->a_ops = &minix_aops; 366 } else 367 init_special_inode(inode, inode->i_mode, rdev); 368 } 369 370 /* 371 * The minix V1 function to read an inode. 372 */ 373 static void V1_minix_read_inode(struct inode * inode) 374 { 375 struct buffer_head * bh; 376 struct minix_inode * raw_inode; 377 struct minix_inode_info *minix_inode = minix_i(inode); 378 int i; 379 380 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 381 if (!raw_inode) { 382 make_bad_inode(inode); 383 return; 384 } 385 inode->i_mode = raw_inode->i_mode; 386 inode->i_uid = (uid_t)raw_inode->i_uid; 387 inode->i_gid = (gid_t)raw_inode->i_gid; 388 inode->i_nlink = raw_inode->i_nlinks; 389 inode->i_size = raw_inode->i_size; 390 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; 391 inode->i_mtime.tv_nsec = 0; 392 inode->i_atime.tv_nsec = 0; 393 inode->i_ctime.tv_nsec = 0; 394 inode->i_blocks = inode->i_blksize = 0; 395 for (i = 0; i < 9; i++) 396 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 397 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 398 brelse(bh); 399 } 400 401 /* 402 * The minix V2 function to read an inode. 403 */ 404 static void V2_minix_read_inode(struct inode * inode) 405 { 406 struct buffer_head * bh; 407 struct minix2_inode * raw_inode; 408 struct minix_inode_info *minix_inode = minix_i(inode); 409 int i; 410 411 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 412 if (!raw_inode) { 413 make_bad_inode(inode); 414 return; 415 } 416 inode->i_mode = raw_inode->i_mode; 417 inode->i_uid = (uid_t)raw_inode->i_uid; 418 inode->i_gid = (gid_t)raw_inode->i_gid; 419 inode->i_nlink = raw_inode->i_nlinks; 420 inode->i_size = raw_inode->i_size; 421 inode->i_mtime.tv_sec = raw_inode->i_mtime; 422 inode->i_atime.tv_sec = raw_inode->i_atime; 423 inode->i_ctime.tv_sec = raw_inode->i_ctime; 424 inode->i_mtime.tv_nsec = 0; 425 inode->i_atime.tv_nsec = 0; 426 inode->i_ctime.tv_nsec = 0; 427 inode->i_blocks = inode->i_blksize = 0; 428 for (i = 0; i < 10; i++) 429 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 430 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 431 brelse(bh); 432 } 433 434 /* 435 * The global function to read an inode. 436 */ 437 static void minix_read_inode(struct inode * inode) 438 { 439 if (INODE_VERSION(inode) == MINIX_V1) 440 V1_minix_read_inode(inode); 441 else 442 V2_minix_read_inode(inode); 443 } 444 445 /* 446 * The minix V1 function to synchronize an inode. 447 */ 448 static struct buffer_head * V1_minix_update_inode(struct inode * inode) 449 { 450 struct buffer_head * bh; 451 struct minix_inode * raw_inode; 452 struct minix_inode_info *minix_inode = minix_i(inode); 453 int i; 454 455 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 456 if (!raw_inode) 457 return NULL; 458 raw_inode->i_mode = inode->i_mode; 459 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 460 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 461 raw_inode->i_nlinks = inode->i_nlink; 462 raw_inode->i_size = inode->i_size; 463 raw_inode->i_time = inode->i_mtime.tv_sec; 464 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 465 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 466 else for (i = 0; i < 9; i++) 467 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 468 mark_buffer_dirty(bh); 469 return bh; 470 } 471 472 /* 473 * The minix V2 function to synchronize an inode. 474 */ 475 static struct buffer_head * V2_minix_update_inode(struct inode * inode) 476 { 477 struct buffer_head * bh; 478 struct minix2_inode * raw_inode; 479 struct minix_inode_info *minix_inode = minix_i(inode); 480 int i; 481 482 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 483 if (!raw_inode) 484 return NULL; 485 raw_inode->i_mode = inode->i_mode; 486 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 487 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 488 raw_inode->i_nlinks = inode->i_nlink; 489 raw_inode->i_size = inode->i_size; 490 raw_inode->i_mtime = inode->i_mtime.tv_sec; 491 raw_inode->i_atime = inode->i_atime.tv_sec; 492 raw_inode->i_ctime = inode->i_ctime.tv_sec; 493 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 494 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 495 else for (i = 0; i < 10; i++) 496 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 497 mark_buffer_dirty(bh); 498 return bh; 499 } 500 501 static struct buffer_head *minix_update_inode(struct inode *inode) 502 { 503 if (INODE_VERSION(inode) == MINIX_V1) 504 return V1_minix_update_inode(inode); 505 else 506 return V2_minix_update_inode(inode); 507 } 508 509 static int minix_write_inode(struct inode * inode, int wait) 510 { 511 brelse(minix_update_inode(inode)); 512 return 0; 513 } 514 515 int minix_sync_inode(struct inode * inode) 516 { 517 int err = 0; 518 struct buffer_head *bh; 519 520 bh = minix_update_inode(inode); 521 if (bh && buffer_dirty(bh)) 522 { 523 sync_dirty_buffer(bh); 524 if (buffer_req(bh) && !buffer_uptodate(bh)) 525 { 526 printk ("IO error syncing minix inode [%s:%08lx]\n", 527 inode->i_sb->s_id, inode->i_ino); 528 err = -1; 529 } 530 } 531 else if (!bh) 532 err = -1; 533 brelse (bh); 534 return err; 535 } 536 537 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 538 { 539 generic_fillattr(dentry->d_inode, stat); 540 if (INODE_VERSION(dentry->d_inode) == MINIX_V1) 541 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size); 542 else 543 stat->blocks = (BLOCK_SIZE / 512) * V2_minix_blocks(stat->size); 544 stat->blksize = BLOCK_SIZE; 545 return 0; 546 } 547 548 /* 549 * The function that is called for file truncation. 550 */ 551 void minix_truncate(struct inode * inode) 552 { 553 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 554 return; 555 if (INODE_VERSION(inode) == MINIX_V1) 556 V1_minix_truncate(inode); 557 else 558 V2_minix_truncate(inode); 559 } 560 561 static struct super_block *minix_get_sb(struct file_system_type *fs_type, 562 int flags, const char *dev_name, void *data) 563 { 564 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super); 565 } 566 567 static struct file_system_type minix_fs_type = { 568 .owner = THIS_MODULE, 569 .name = "minix", 570 .get_sb = minix_get_sb, 571 .kill_sb = kill_block_super, 572 .fs_flags = FS_REQUIRES_DEV, 573 }; 574 575 static int __init init_minix_fs(void) 576 { 577 int err = init_inodecache(); 578 if (err) 579 goto out1; 580 err = register_filesystem(&minix_fs_type); 581 if (err) 582 goto out; 583 return 0; 584 out: 585 destroy_inodecache(); 586 out1: 587 return err; 588 } 589 590 static void __exit exit_minix_fs(void) 591 { 592 unregister_filesystem(&minix_fs_type); 593 destroy_inodecache(); 594 } 595 596 module_init(init_minix_fs) 597 module_exit(exit_minix_fs) 598 MODULE_LICENSE("GPL"); 599 600