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 dentry *dentry, 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 SLAB_MEM_SPREAD), 85 init_once, NULL); 86 if (minix_inode_cachep == NULL) 87 return -ENOMEM; 88 return 0; 89 } 90 91 static void destroy_inodecache(void) 92 { 93 if (kmem_cache_destroy(minix_inode_cachep)) 94 printk(KERN_INFO "minix_inode_cache: not all structures were freed\n"); 95 } 96 97 static struct super_operations minix_sops = { 98 .alloc_inode = minix_alloc_inode, 99 .destroy_inode = minix_destroy_inode, 100 .read_inode = minix_read_inode, 101 .write_inode = minix_write_inode, 102 .delete_inode = minix_delete_inode, 103 .put_super = minix_put_super, 104 .statfs = minix_statfs, 105 .remount_fs = minix_remount, 106 }; 107 108 static int minix_remount (struct super_block * sb, int * flags, char * data) 109 { 110 struct minix_sb_info * sbi = minix_sb(sb); 111 struct minix_super_block * ms; 112 113 ms = sbi->s_ms; 114 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 115 return 0; 116 if (*flags & MS_RDONLY) { 117 if (ms->s_state & MINIX_VALID_FS || 118 !(sbi->s_mount_state & MINIX_VALID_FS)) 119 return 0; 120 /* Mounting a rw partition read-only. */ 121 ms->s_state = sbi->s_mount_state; 122 mark_buffer_dirty(sbi->s_sbh); 123 } else { 124 /* Mount a partition which is read-only, read-write. */ 125 sbi->s_mount_state = ms->s_state; 126 ms->s_state &= ~MINIX_VALID_FS; 127 mark_buffer_dirty(sbi->s_sbh); 128 129 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 130 printk("MINIX-fs warning: remounting unchecked fs, " 131 "running fsck is recommended\n"); 132 else if ((sbi->s_mount_state & MINIX_ERROR_FS)) 133 printk("MINIX-fs warning: remounting fs with errors, " 134 "running fsck is recommended\n"); 135 } 136 return 0; 137 } 138 139 static int minix_fill_super(struct super_block *s, void *data, int silent) 140 { 141 struct buffer_head *bh; 142 struct buffer_head **map; 143 struct minix_super_block *ms; 144 int i, block; 145 struct inode *root_inode; 146 struct minix_sb_info *sbi; 147 148 sbi = kmalloc(sizeof(struct minix_sb_info), GFP_KERNEL); 149 if (!sbi) 150 return -ENOMEM; 151 s->s_fs_info = sbi; 152 memset(sbi, 0, sizeof(struct minix_sb_info)); 153 154 /* N.B. These should be compile-time tests. 155 Unfortunately that is impossible. */ 156 if (32 != sizeof (struct minix_inode)) 157 panic("bad V1 i-node size"); 158 if (64 != sizeof(struct minix2_inode)) 159 panic("bad V2 i-node size"); 160 161 if (!sb_set_blocksize(s, BLOCK_SIZE)) 162 goto out_bad_hblock; 163 164 if (!(bh = sb_bread(s, 1))) 165 goto out_bad_sb; 166 167 ms = (struct minix_super_block *) bh->b_data; 168 sbi->s_ms = ms; 169 sbi->s_sbh = bh; 170 sbi->s_mount_state = ms->s_state; 171 sbi->s_ninodes = ms->s_ninodes; 172 sbi->s_nzones = ms->s_nzones; 173 sbi->s_imap_blocks = ms->s_imap_blocks; 174 sbi->s_zmap_blocks = ms->s_zmap_blocks; 175 sbi->s_firstdatazone = ms->s_firstdatazone; 176 sbi->s_log_zone_size = ms->s_log_zone_size; 177 sbi->s_max_size = ms->s_max_size; 178 s->s_magic = ms->s_magic; 179 if (s->s_magic == MINIX_SUPER_MAGIC) { 180 sbi->s_version = MINIX_V1; 181 sbi->s_dirsize = 16; 182 sbi->s_namelen = 14; 183 sbi->s_link_max = MINIX_LINK_MAX; 184 } else if (s->s_magic == MINIX_SUPER_MAGIC2) { 185 sbi->s_version = MINIX_V1; 186 sbi->s_dirsize = 32; 187 sbi->s_namelen = 30; 188 sbi->s_link_max = MINIX_LINK_MAX; 189 } else if (s->s_magic == MINIX2_SUPER_MAGIC) { 190 sbi->s_version = MINIX_V2; 191 sbi->s_nzones = ms->s_zones; 192 sbi->s_dirsize = 16; 193 sbi->s_namelen = 14; 194 sbi->s_link_max = MINIX2_LINK_MAX; 195 } else if (s->s_magic == MINIX2_SUPER_MAGIC2) { 196 sbi->s_version = MINIX_V2; 197 sbi->s_nzones = ms->s_zones; 198 sbi->s_dirsize = 32; 199 sbi->s_namelen = 30; 200 sbi->s_link_max = MINIX2_LINK_MAX; 201 } else 202 goto out_no_fs; 203 204 /* 205 * Allocate the buffer map to keep the superblock small. 206 */ 207 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 208 map = kmalloc(i, GFP_KERNEL); 209 if (!map) 210 goto out_no_map; 211 memset(map, 0, i); 212 sbi->s_imap = &map[0]; 213 sbi->s_zmap = &map[sbi->s_imap_blocks]; 214 215 block=2; 216 for (i=0 ; i < sbi->s_imap_blocks ; i++) { 217 if (!(sbi->s_imap[i]=sb_bread(s, block))) 218 goto out_no_bitmap; 219 block++; 220 } 221 for (i=0 ; i < sbi->s_zmap_blocks ; i++) { 222 if (!(sbi->s_zmap[i]=sb_bread(s, block))) 223 goto out_no_bitmap; 224 block++; 225 } 226 227 minix_set_bit(0,sbi->s_imap[0]->b_data); 228 minix_set_bit(0,sbi->s_zmap[0]->b_data); 229 230 /* set up enough so that it can read an inode */ 231 s->s_op = &minix_sops; 232 root_inode = iget(s, MINIX_ROOT_INO); 233 if (!root_inode || is_bad_inode(root_inode)) 234 goto out_no_root; 235 236 s->s_root = d_alloc_root(root_inode); 237 if (!s->s_root) 238 goto out_iput; 239 240 if (!NO_TRUNCATE) 241 s->s_root->d_op = &minix_dentry_operations; 242 243 if (!(s->s_flags & MS_RDONLY)) { 244 ms->s_state &= ~MINIX_VALID_FS; 245 mark_buffer_dirty(bh); 246 } 247 if (!(sbi->s_mount_state & MINIX_VALID_FS)) 248 printk("MINIX-fs: mounting unchecked file system, " 249 "running fsck is recommended\n"); 250 else if (sbi->s_mount_state & MINIX_ERROR_FS) 251 printk("MINIX-fs: mounting file system with errors, " 252 "running fsck is recommended\n"); 253 return 0; 254 255 out_iput: 256 iput(root_inode); 257 goto out_freemap; 258 259 out_no_root: 260 if (!silent) 261 printk("MINIX-fs: get root inode failed\n"); 262 goto out_freemap; 263 264 out_no_bitmap: 265 printk("MINIX-fs: bad superblock or unable to read bitmaps\n"); 266 out_freemap: 267 for (i = 0; i < sbi->s_imap_blocks; i++) 268 brelse(sbi->s_imap[i]); 269 for (i = 0; i < sbi->s_zmap_blocks; i++) 270 brelse(sbi->s_zmap[i]); 271 kfree(sbi->s_imap); 272 goto out_release; 273 274 out_no_map: 275 if (!silent) 276 printk("MINIX-fs: can't allocate map\n"); 277 goto out_release; 278 279 out_no_fs: 280 if (!silent) 281 printk("VFS: Can't find a Minix or Minix V2 filesystem " 282 "on device %s\n", s->s_id); 283 out_release: 284 brelse(bh); 285 goto out; 286 287 out_bad_hblock: 288 printk("MINIX-fs: blocksize too small for device\n"); 289 goto out; 290 291 out_bad_sb: 292 printk("MINIX-fs: unable to read superblock\n"); 293 out: 294 s->s_fs_info = NULL; 295 kfree(sbi); 296 return -EINVAL; 297 } 298 299 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf) 300 { 301 struct minix_sb_info *sbi = minix_sb(dentry->d_sb); 302 buf->f_type = dentry->d_sb->s_magic; 303 buf->f_bsize = dentry->d_sb->s_blocksize; 304 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; 305 buf->f_bfree = minix_count_free_blocks(sbi); 306 buf->f_bavail = buf->f_bfree; 307 buf->f_files = sbi->s_ninodes; 308 buf->f_ffree = minix_count_free_inodes(sbi); 309 buf->f_namelen = sbi->s_namelen; 310 return 0; 311 } 312 313 static int minix_get_block(struct inode *inode, sector_t block, 314 struct buffer_head *bh_result, int create) 315 { 316 if (INODE_VERSION(inode) == MINIX_V1) 317 return V1_minix_get_block(inode, block, bh_result, create); 318 else 319 return V2_minix_get_block(inode, block, bh_result, create); 320 } 321 322 static int minix_writepage(struct page *page, struct writeback_control *wbc) 323 { 324 return block_write_full_page(page, minix_get_block, wbc); 325 } 326 static int minix_readpage(struct file *file, struct page *page) 327 { 328 return block_read_full_page(page,minix_get_block); 329 } 330 static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) 331 { 332 return block_prepare_write(page,from,to,minix_get_block); 333 } 334 static sector_t minix_bmap(struct address_space *mapping, sector_t block) 335 { 336 return generic_block_bmap(mapping,block,minix_get_block); 337 } 338 static const struct address_space_operations minix_aops = { 339 .readpage = minix_readpage, 340 .writepage = minix_writepage, 341 .sync_page = block_sync_page, 342 .prepare_write = minix_prepare_write, 343 .commit_write = generic_commit_write, 344 .bmap = minix_bmap 345 }; 346 347 static struct inode_operations minix_symlink_inode_operations = { 348 .readlink = generic_readlink, 349 .follow_link = page_follow_link_light, 350 .put_link = page_put_link, 351 .getattr = minix_getattr, 352 }; 353 354 void minix_set_inode(struct inode *inode, dev_t rdev) 355 { 356 if (S_ISREG(inode->i_mode)) { 357 inode->i_op = &minix_file_inode_operations; 358 inode->i_fop = &minix_file_operations; 359 inode->i_mapping->a_ops = &minix_aops; 360 } else if (S_ISDIR(inode->i_mode)) { 361 inode->i_op = &minix_dir_inode_operations; 362 inode->i_fop = &minix_dir_operations; 363 inode->i_mapping->a_ops = &minix_aops; 364 } else if (S_ISLNK(inode->i_mode)) { 365 inode->i_op = &minix_symlink_inode_operations; 366 inode->i_mapping->a_ops = &minix_aops; 367 } else 368 init_special_inode(inode, inode->i_mode, rdev); 369 } 370 371 /* 372 * The minix V1 function to read an inode. 373 */ 374 static void V1_minix_read_inode(struct inode * inode) 375 { 376 struct buffer_head * bh; 377 struct minix_inode * raw_inode; 378 struct minix_inode_info *minix_inode = minix_i(inode); 379 int i; 380 381 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 382 if (!raw_inode) { 383 make_bad_inode(inode); 384 return; 385 } 386 inode->i_mode = raw_inode->i_mode; 387 inode->i_uid = (uid_t)raw_inode->i_uid; 388 inode->i_gid = (gid_t)raw_inode->i_gid; 389 inode->i_nlink = raw_inode->i_nlinks; 390 inode->i_size = raw_inode->i_size; 391 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; 392 inode->i_mtime.tv_nsec = 0; 393 inode->i_atime.tv_nsec = 0; 394 inode->i_ctime.tv_nsec = 0; 395 inode->i_blocks = inode->i_blksize = 0; 396 for (i = 0; i < 9; i++) 397 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 398 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 399 brelse(bh); 400 } 401 402 /* 403 * The minix V2 function to read an inode. 404 */ 405 static void V2_minix_read_inode(struct inode * inode) 406 { 407 struct buffer_head * bh; 408 struct minix2_inode * raw_inode; 409 struct minix_inode_info *minix_inode = minix_i(inode); 410 int i; 411 412 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 413 if (!raw_inode) { 414 make_bad_inode(inode); 415 return; 416 } 417 inode->i_mode = raw_inode->i_mode; 418 inode->i_uid = (uid_t)raw_inode->i_uid; 419 inode->i_gid = (gid_t)raw_inode->i_gid; 420 inode->i_nlink = raw_inode->i_nlinks; 421 inode->i_size = raw_inode->i_size; 422 inode->i_mtime.tv_sec = raw_inode->i_mtime; 423 inode->i_atime.tv_sec = raw_inode->i_atime; 424 inode->i_ctime.tv_sec = raw_inode->i_ctime; 425 inode->i_mtime.tv_nsec = 0; 426 inode->i_atime.tv_nsec = 0; 427 inode->i_ctime.tv_nsec = 0; 428 inode->i_blocks = inode->i_blksize = 0; 429 for (i = 0; i < 10; i++) 430 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 431 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 432 brelse(bh); 433 } 434 435 /* 436 * The global function to read an inode. 437 */ 438 static void minix_read_inode(struct inode * inode) 439 { 440 if (INODE_VERSION(inode) == MINIX_V1) 441 V1_minix_read_inode(inode); 442 else 443 V2_minix_read_inode(inode); 444 } 445 446 /* 447 * The minix V1 function to synchronize an inode. 448 */ 449 static struct buffer_head * V1_minix_update_inode(struct inode * inode) 450 { 451 struct buffer_head * bh; 452 struct minix_inode * raw_inode; 453 struct minix_inode_info *minix_inode = minix_i(inode); 454 int i; 455 456 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 457 if (!raw_inode) 458 return NULL; 459 raw_inode->i_mode = inode->i_mode; 460 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 461 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 462 raw_inode->i_nlinks = inode->i_nlink; 463 raw_inode->i_size = inode->i_size; 464 raw_inode->i_time = inode->i_mtime.tv_sec; 465 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 466 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 467 else for (i = 0; i < 9; i++) 468 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 469 mark_buffer_dirty(bh); 470 return bh; 471 } 472 473 /* 474 * The minix V2 function to synchronize an inode. 475 */ 476 static struct buffer_head * V2_minix_update_inode(struct inode * inode) 477 { 478 struct buffer_head * bh; 479 struct minix2_inode * raw_inode; 480 struct minix_inode_info *minix_inode = minix_i(inode); 481 int i; 482 483 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 484 if (!raw_inode) 485 return NULL; 486 raw_inode->i_mode = inode->i_mode; 487 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 488 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 489 raw_inode->i_nlinks = inode->i_nlink; 490 raw_inode->i_size = inode->i_size; 491 raw_inode->i_mtime = inode->i_mtime.tv_sec; 492 raw_inode->i_atime = inode->i_atime.tv_sec; 493 raw_inode->i_ctime = inode->i_ctime.tv_sec; 494 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 495 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 496 else for (i = 0; i < 10; i++) 497 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 498 mark_buffer_dirty(bh); 499 return bh; 500 } 501 502 static struct buffer_head *minix_update_inode(struct inode *inode) 503 { 504 if (INODE_VERSION(inode) == MINIX_V1) 505 return V1_minix_update_inode(inode); 506 else 507 return V2_minix_update_inode(inode); 508 } 509 510 static int minix_write_inode(struct inode * inode, int wait) 511 { 512 brelse(minix_update_inode(inode)); 513 return 0; 514 } 515 516 int minix_sync_inode(struct inode * inode) 517 { 518 int err = 0; 519 struct buffer_head *bh; 520 521 bh = minix_update_inode(inode); 522 if (bh && buffer_dirty(bh)) 523 { 524 sync_dirty_buffer(bh); 525 if (buffer_req(bh) && !buffer_uptodate(bh)) 526 { 527 printk("IO error syncing minix inode [%s:%08lx]\n", 528 inode->i_sb->s_id, inode->i_ino); 529 err = -1; 530 } 531 } 532 else if (!bh) 533 err = -1; 534 brelse (bh); 535 return err; 536 } 537 538 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 539 { 540 generic_fillattr(dentry->d_inode, stat); 541 if (INODE_VERSION(dentry->d_inode) == MINIX_V1) 542 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size); 543 else 544 stat->blocks = (BLOCK_SIZE / 512) * V2_minix_blocks(stat->size); 545 stat->blksize = BLOCK_SIZE; 546 return 0; 547 } 548 549 /* 550 * The function that is called for file truncation. 551 */ 552 void minix_truncate(struct inode * inode) 553 { 554 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 555 return; 556 if (INODE_VERSION(inode) == MINIX_V1) 557 V1_minix_truncate(inode); 558 else 559 V2_minix_truncate(inode); 560 } 561 562 static int minix_get_sb(struct file_system_type *fs_type, 563 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 564 { 565 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super, 566 mnt); 567 } 568 569 static struct file_system_type minix_fs_type = { 570 .owner = THIS_MODULE, 571 .name = "minix", 572 .get_sb = minix_get_sb, 573 .kill_sb = kill_block_super, 574 .fs_flags = FS_REQUIRES_DEV, 575 }; 576 577 static int __init init_minix_fs(void) 578 { 579 int err = init_inodecache(); 580 if (err) 581 goto out1; 582 err = register_filesystem(&minix_fs_type); 583 if (err) 584 goto out; 585 return 0; 586 out: 587 destroy_inodecache(); 588 out1: 589 return err; 590 } 591 592 static void __exit exit_minix_fs(void) 593 { 594 unregister_filesystem(&minix_fs_type); 595 destroy_inodecache(); 596 } 597 598 module_init(init_minix_fs) 599 module_exit(exit_minix_fs) 600 MODULE_LICENSE("GPL"); 601 602