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 = kzalloc(sizeof(struct minix_sb_info), GFP_KERNEL); 149 if (!sbi) 150 return -ENOMEM; 151 s->s_fs_info = sbi; 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 if (sbi->s_imap_blocks == 0 || sbi->s_zmap_blocks == 0) 207 goto out_illegal_sb; 208 i = (sbi->s_imap_blocks + sbi->s_zmap_blocks) * sizeof(bh); 209 map = kzalloc(i, GFP_KERNEL); 210 if (!map) 211 goto out_no_map; 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_illegal_sb: 280 if (!silent) 281 printk("MINIX-fs: bad superblock\n"); 282 goto out_release; 283 284 out_no_fs: 285 if (!silent) 286 printk("VFS: Can't find a Minix or Minix V2 filesystem " 287 "on device %s\n", s->s_id); 288 out_release: 289 brelse(bh); 290 goto out; 291 292 out_bad_hblock: 293 printk("MINIX-fs: blocksize too small for device\n"); 294 goto out; 295 296 out_bad_sb: 297 printk("MINIX-fs: unable to read superblock\n"); 298 out: 299 s->s_fs_info = NULL; 300 kfree(sbi); 301 return -EINVAL; 302 } 303 304 static int minix_statfs(struct dentry *dentry, struct kstatfs *buf) 305 { 306 struct minix_sb_info *sbi = minix_sb(dentry->d_sb); 307 buf->f_type = dentry->d_sb->s_magic; 308 buf->f_bsize = dentry->d_sb->s_blocksize; 309 buf->f_blocks = (sbi->s_nzones - sbi->s_firstdatazone) << sbi->s_log_zone_size; 310 buf->f_bfree = minix_count_free_blocks(sbi); 311 buf->f_bavail = buf->f_bfree; 312 buf->f_files = sbi->s_ninodes; 313 buf->f_ffree = minix_count_free_inodes(sbi); 314 buf->f_namelen = sbi->s_namelen; 315 return 0; 316 } 317 318 static int minix_get_block(struct inode *inode, sector_t block, 319 struct buffer_head *bh_result, int create) 320 { 321 if (INODE_VERSION(inode) == MINIX_V1) 322 return V1_minix_get_block(inode, block, bh_result, create); 323 else 324 return V2_minix_get_block(inode, block, bh_result, create); 325 } 326 327 static int minix_writepage(struct page *page, struct writeback_control *wbc) 328 { 329 return block_write_full_page(page, minix_get_block, wbc); 330 } 331 static int minix_readpage(struct file *file, struct page *page) 332 { 333 return block_read_full_page(page,minix_get_block); 334 } 335 static int minix_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) 336 { 337 return block_prepare_write(page,from,to,minix_get_block); 338 } 339 static sector_t minix_bmap(struct address_space *mapping, sector_t block) 340 { 341 return generic_block_bmap(mapping,block,minix_get_block); 342 } 343 static const struct address_space_operations minix_aops = { 344 .readpage = minix_readpage, 345 .writepage = minix_writepage, 346 .sync_page = block_sync_page, 347 .prepare_write = minix_prepare_write, 348 .commit_write = generic_commit_write, 349 .bmap = minix_bmap 350 }; 351 352 static struct inode_operations minix_symlink_inode_operations = { 353 .readlink = generic_readlink, 354 .follow_link = page_follow_link_light, 355 .put_link = page_put_link, 356 .getattr = minix_getattr, 357 }; 358 359 void minix_set_inode(struct inode *inode, dev_t rdev) 360 { 361 if (S_ISREG(inode->i_mode)) { 362 inode->i_op = &minix_file_inode_operations; 363 inode->i_fop = &minix_file_operations; 364 inode->i_mapping->a_ops = &minix_aops; 365 } else if (S_ISDIR(inode->i_mode)) { 366 inode->i_op = &minix_dir_inode_operations; 367 inode->i_fop = &minix_dir_operations; 368 inode->i_mapping->a_ops = &minix_aops; 369 } else if (S_ISLNK(inode->i_mode)) { 370 inode->i_op = &minix_symlink_inode_operations; 371 inode->i_mapping->a_ops = &minix_aops; 372 } else 373 init_special_inode(inode, inode->i_mode, rdev); 374 } 375 376 /* 377 * The minix V1 function to read an inode. 378 */ 379 static void V1_minix_read_inode(struct inode * inode) 380 { 381 struct buffer_head * bh; 382 struct minix_inode * raw_inode; 383 struct minix_inode_info *minix_inode = minix_i(inode); 384 int i; 385 386 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 387 if (!raw_inode) { 388 make_bad_inode(inode); 389 return; 390 } 391 inode->i_mode = raw_inode->i_mode; 392 inode->i_uid = (uid_t)raw_inode->i_uid; 393 inode->i_gid = (gid_t)raw_inode->i_gid; 394 inode->i_nlink = raw_inode->i_nlinks; 395 inode->i_size = raw_inode->i_size; 396 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = raw_inode->i_time; 397 inode->i_mtime.tv_nsec = 0; 398 inode->i_atime.tv_nsec = 0; 399 inode->i_ctime.tv_nsec = 0; 400 inode->i_blocks = inode->i_blksize = 0; 401 for (i = 0; i < 9; i++) 402 minix_inode->u.i1_data[i] = raw_inode->i_zone[i]; 403 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 404 brelse(bh); 405 } 406 407 /* 408 * The minix V2 function to read an inode. 409 */ 410 static void V2_minix_read_inode(struct inode * inode) 411 { 412 struct buffer_head * bh; 413 struct minix2_inode * raw_inode; 414 struct minix_inode_info *minix_inode = minix_i(inode); 415 int i; 416 417 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 418 if (!raw_inode) { 419 make_bad_inode(inode); 420 return; 421 } 422 inode->i_mode = raw_inode->i_mode; 423 inode->i_uid = (uid_t)raw_inode->i_uid; 424 inode->i_gid = (gid_t)raw_inode->i_gid; 425 inode->i_nlink = raw_inode->i_nlinks; 426 inode->i_size = raw_inode->i_size; 427 inode->i_mtime.tv_sec = raw_inode->i_mtime; 428 inode->i_atime.tv_sec = raw_inode->i_atime; 429 inode->i_ctime.tv_sec = raw_inode->i_ctime; 430 inode->i_mtime.tv_nsec = 0; 431 inode->i_atime.tv_nsec = 0; 432 inode->i_ctime.tv_nsec = 0; 433 inode->i_blocks = inode->i_blksize = 0; 434 for (i = 0; i < 10; i++) 435 minix_inode->u.i2_data[i] = raw_inode->i_zone[i]; 436 minix_set_inode(inode, old_decode_dev(raw_inode->i_zone[0])); 437 brelse(bh); 438 } 439 440 /* 441 * The global function to read an inode. 442 */ 443 static void minix_read_inode(struct inode * inode) 444 { 445 if (INODE_VERSION(inode) == MINIX_V1) 446 V1_minix_read_inode(inode); 447 else 448 V2_minix_read_inode(inode); 449 } 450 451 /* 452 * The minix V1 function to synchronize an inode. 453 */ 454 static struct buffer_head * V1_minix_update_inode(struct inode * inode) 455 { 456 struct buffer_head * bh; 457 struct minix_inode * raw_inode; 458 struct minix_inode_info *minix_inode = minix_i(inode); 459 int i; 460 461 raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh); 462 if (!raw_inode) 463 return NULL; 464 raw_inode->i_mode = inode->i_mode; 465 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 466 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 467 raw_inode->i_nlinks = inode->i_nlink; 468 raw_inode->i_size = inode->i_size; 469 raw_inode->i_time = inode->i_mtime.tv_sec; 470 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 471 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 472 else for (i = 0; i < 9; i++) 473 raw_inode->i_zone[i] = minix_inode->u.i1_data[i]; 474 mark_buffer_dirty(bh); 475 return bh; 476 } 477 478 /* 479 * The minix V2 function to synchronize an inode. 480 */ 481 static struct buffer_head * V2_minix_update_inode(struct inode * inode) 482 { 483 struct buffer_head * bh; 484 struct minix2_inode * raw_inode; 485 struct minix_inode_info *minix_inode = minix_i(inode); 486 int i; 487 488 raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh); 489 if (!raw_inode) 490 return NULL; 491 raw_inode->i_mode = inode->i_mode; 492 raw_inode->i_uid = fs_high2lowuid(inode->i_uid); 493 raw_inode->i_gid = fs_high2lowgid(inode->i_gid); 494 raw_inode->i_nlinks = inode->i_nlink; 495 raw_inode->i_size = inode->i_size; 496 raw_inode->i_mtime = inode->i_mtime.tv_sec; 497 raw_inode->i_atime = inode->i_atime.tv_sec; 498 raw_inode->i_ctime = inode->i_ctime.tv_sec; 499 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) 500 raw_inode->i_zone[0] = old_encode_dev(inode->i_rdev); 501 else for (i = 0; i < 10; i++) 502 raw_inode->i_zone[i] = minix_inode->u.i2_data[i]; 503 mark_buffer_dirty(bh); 504 return bh; 505 } 506 507 static struct buffer_head *minix_update_inode(struct inode *inode) 508 { 509 if (INODE_VERSION(inode) == MINIX_V1) 510 return V1_minix_update_inode(inode); 511 else 512 return V2_minix_update_inode(inode); 513 } 514 515 static int minix_write_inode(struct inode * inode, int wait) 516 { 517 brelse(minix_update_inode(inode)); 518 return 0; 519 } 520 521 int minix_sync_inode(struct inode * inode) 522 { 523 int err = 0; 524 struct buffer_head *bh; 525 526 bh = minix_update_inode(inode); 527 if (bh && buffer_dirty(bh)) 528 { 529 sync_dirty_buffer(bh); 530 if (buffer_req(bh) && !buffer_uptodate(bh)) 531 { 532 printk("IO error syncing minix inode [%s:%08lx]\n", 533 inode->i_sb->s_id, inode->i_ino); 534 err = -1; 535 } 536 } 537 else if (!bh) 538 err = -1; 539 brelse (bh); 540 return err; 541 } 542 543 int minix_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 544 { 545 generic_fillattr(dentry->d_inode, stat); 546 if (INODE_VERSION(dentry->d_inode) == MINIX_V1) 547 stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size); 548 else 549 stat->blocks = (BLOCK_SIZE / 512) * V2_minix_blocks(stat->size); 550 stat->blksize = BLOCK_SIZE; 551 return 0; 552 } 553 554 /* 555 * The function that is called for file truncation. 556 */ 557 void minix_truncate(struct inode * inode) 558 { 559 if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) 560 return; 561 if (INODE_VERSION(inode) == MINIX_V1) 562 V1_minix_truncate(inode); 563 else 564 V2_minix_truncate(inode); 565 } 566 567 static int minix_get_sb(struct file_system_type *fs_type, 568 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 569 { 570 return get_sb_bdev(fs_type, flags, dev_name, data, minix_fill_super, 571 mnt); 572 } 573 574 static struct file_system_type minix_fs_type = { 575 .owner = THIS_MODULE, 576 .name = "minix", 577 .get_sb = minix_get_sb, 578 .kill_sb = kill_block_super, 579 .fs_flags = FS_REQUIRES_DEV, 580 }; 581 582 static int __init init_minix_fs(void) 583 { 584 int err = init_inodecache(); 585 if (err) 586 goto out1; 587 err = register_filesystem(&minix_fs_type); 588 if (err) 589 goto out; 590 return 0; 591 out: 592 destroy_inodecache(); 593 out1: 594 return err; 595 } 596 597 static void __exit exit_minix_fs(void) 598 { 599 unregister_filesystem(&minix_fs_type); 600 destroy_inodecache(); 601 } 602 603 module_init(init_minix_fs) 604 module_exit(exit_minix_fs) 605 MODULE_LICENSE("GPL"); 606 607