1 /* 2 * linux/fs/affs/inode.c 3 * 4 * (c) 1996 Hans-Joachim Widmaier - Rewritten 5 * 6 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem. 7 * 8 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem. 9 * 10 * (C) 1991 Linus Torvalds - minix filesystem 11 */ 12 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/statfs.h> 16 #include <linux/parser.h> 17 #include <linux/magic.h> 18 #include <linux/sched.h> 19 #include <linux/slab.h> 20 #include <linux/writeback.h> 21 #include "affs.h" 22 23 extern struct timezone sys_tz; 24 25 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf); 26 static int affs_remount (struct super_block *sb, int *flags, char *data); 27 28 static void 29 affs_commit_super(struct super_block *sb, int wait) 30 { 31 struct affs_sb_info *sbi = AFFS_SB(sb); 32 struct buffer_head *bh = sbi->s_root_bh; 33 struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh); 34 35 lock_buffer(bh); 36 secs_to_datestamp(get_seconds(), &tail->disk_change); 37 affs_fix_checksum(sb, bh); 38 unlock_buffer(bh); 39 40 mark_buffer_dirty(bh); 41 if (wait) 42 sync_dirty_buffer(bh); 43 } 44 45 static void 46 affs_put_super(struct super_block *sb) 47 { 48 struct affs_sb_info *sbi = AFFS_SB(sb); 49 pr_debug("%s()\n", __func__); 50 51 cancel_delayed_work_sync(&sbi->sb_work); 52 } 53 54 static int 55 affs_sync_fs(struct super_block *sb, int wait) 56 { 57 affs_commit_super(sb, wait); 58 return 0; 59 } 60 61 static void flush_superblock(struct work_struct *work) 62 { 63 struct affs_sb_info *sbi; 64 struct super_block *sb; 65 66 sbi = container_of(work, struct affs_sb_info, sb_work.work); 67 sb = sbi->sb; 68 69 spin_lock(&sbi->work_lock); 70 sbi->work_queued = 0; 71 spin_unlock(&sbi->work_lock); 72 73 affs_commit_super(sb, 1); 74 } 75 76 void affs_mark_sb_dirty(struct super_block *sb) 77 { 78 struct affs_sb_info *sbi = AFFS_SB(sb); 79 unsigned long delay; 80 81 if (sb->s_flags & MS_RDONLY) 82 return; 83 84 spin_lock(&sbi->work_lock); 85 if (!sbi->work_queued) { 86 delay = msecs_to_jiffies(dirty_writeback_interval * 10); 87 queue_delayed_work(system_long_wq, &sbi->sb_work, delay); 88 sbi->work_queued = 1; 89 } 90 spin_unlock(&sbi->work_lock); 91 } 92 93 static struct kmem_cache * affs_inode_cachep; 94 95 static struct inode *affs_alloc_inode(struct super_block *sb) 96 { 97 struct affs_inode_info *i; 98 99 i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL); 100 if (!i) 101 return NULL; 102 103 i->vfs_inode.i_version = 1; 104 i->i_lc = NULL; 105 i->i_ext_bh = NULL; 106 i->i_pa_cnt = 0; 107 108 return &i->vfs_inode; 109 } 110 111 static void affs_i_callback(struct rcu_head *head) 112 { 113 struct inode *inode = container_of(head, struct inode, i_rcu); 114 kmem_cache_free(affs_inode_cachep, AFFS_I(inode)); 115 } 116 117 static void affs_destroy_inode(struct inode *inode) 118 { 119 call_rcu(&inode->i_rcu, affs_i_callback); 120 } 121 122 static void init_once(void *foo) 123 { 124 struct affs_inode_info *ei = (struct affs_inode_info *) foo; 125 126 sema_init(&ei->i_link_lock, 1); 127 sema_init(&ei->i_ext_lock, 1); 128 inode_init_once(&ei->vfs_inode); 129 } 130 131 static int __init init_inodecache(void) 132 { 133 affs_inode_cachep = kmem_cache_create("affs_inode_cache", 134 sizeof(struct affs_inode_info), 135 0, (SLAB_RECLAIM_ACCOUNT| 136 SLAB_MEM_SPREAD), 137 init_once); 138 if (affs_inode_cachep == NULL) 139 return -ENOMEM; 140 return 0; 141 } 142 143 static void destroy_inodecache(void) 144 { 145 /* 146 * Make sure all delayed rcu free inodes are flushed before we 147 * destroy cache. 148 */ 149 rcu_barrier(); 150 kmem_cache_destroy(affs_inode_cachep); 151 } 152 153 static const struct super_operations affs_sops = { 154 .alloc_inode = affs_alloc_inode, 155 .destroy_inode = affs_destroy_inode, 156 .write_inode = affs_write_inode, 157 .evict_inode = affs_evict_inode, 158 .put_super = affs_put_super, 159 .sync_fs = affs_sync_fs, 160 .statfs = affs_statfs, 161 .remount_fs = affs_remount, 162 .show_options = generic_show_options, 163 }; 164 165 enum { 166 Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect, 167 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid, 168 Opt_verbose, Opt_volume, Opt_ignore, Opt_err, 169 }; 170 171 static const match_table_t tokens = { 172 {Opt_bs, "bs=%u"}, 173 {Opt_mode, "mode=%o"}, 174 {Opt_mufs, "mufs"}, 175 {Opt_notruncate, "nofilenametruncate"}, 176 {Opt_prefix, "prefix=%s"}, 177 {Opt_protect, "protect"}, 178 {Opt_reserved, "reserved=%u"}, 179 {Opt_root, "root=%u"}, 180 {Opt_setgid, "setgid=%u"}, 181 {Opt_setuid, "setuid=%u"}, 182 {Opt_verbose, "verbose"}, 183 {Opt_volume, "volume=%s"}, 184 {Opt_ignore, "grpquota"}, 185 {Opt_ignore, "noquota"}, 186 {Opt_ignore, "quota"}, 187 {Opt_ignore, "usrquota"}, 188 {Opt_err, NULL}, 189 }; 190 191 static int 192 parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root, 193 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts) 194 { 195 char *p; 196 substring_t args[MAX_OPT_ARGS]; 197 198 /* Fill in defaults */ 199 200 *uid = current_uid(); 201 *gid = current_gid(); 202 *reserved = 2; 203 *root = -1; 204 *blocksize = -1; 205 volume[0] = ':'; 206 volume[1] = 0; 207 *mount_opts = 0; 208 if (!options) 209 return 1; 210 211 while ((p = strsep(&options, ",")) != NULL) { 212 int token, n, option; 213 if (!*p) 214 continue; 215 216 token = match_token(p, tokens, args); 217 switch (token) { 218 case Opt_bs: 219 if (match_int(&args[0], &n)) 220 return 0; 221 if (n != 512 && n != 1024 && n != 2048 222 && n != 4096) { 223 pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n"); 224 return 0; 225 } 226 *blocksize = n; 227 break; 228 case Opt_mode: 229 if (match_octal(&args[0], &option)) 230 return 0; 231 *mode = option & 0777; 232 *mount_opts |= SF_SETMODE; 233 break; 234 case Opt_mufs: 235 *mount_opts |= SF_MUFS; 236 break; 237 case Opt_notruncate: 238 *mount_opts |= SF_NO_TRUNCATE; 239 break; 240 case Opt_prefix: 241 *prefix = match_strdup(&args[0]); 242 if (!*prefix) 243 return 0; 244 *mount_opts |= SF_PREFIX; 245 break; 246 case Opt_protect: 247 *mount_opts |= SF_IMMUTABLE; 248 break; 249 case Opt_reserved: 250 if (match_int(&args[0], reserved)) 251 return 0; 252 break; 253 case Opt_root: 254 if (match_int(&args[0], root)) 255 return 0; 256 break; 257 case Opt_setgid: 258 if (match_int(&args[0], &option)) 259 return 0; 260 *gid = make_kgid(current_user_ns(), option); 261 if (!gid_valid(*gid)) 262 return 0; 263 *mount_opts |= SF_SETGID; 264 break; 265 case Opt_setuid: 266 if (match_int(&args[0], &option)) 267 return 0; 268 *uid = make_kuid(current_user_ns(), option); 269 if (!uid_valid(*uid)) 270 return 0; 271 *mount_opts |= SF_SETUID; 272 break; 273 case Opt_verbose: 274 *mount_opts |= SF_VERBOSE; 275 break; 276 case Opt_volume: { 277 char *vol = match_strdup(&args[0]); 278 if (!vol) 279 return 0; 280 strlcpy(volume, vol, 32); 281 kfree(vol); 282 break; 283 } 284 case Opt_ignore: 285 /* Silently ignore the quota options */ 286 break; 287 default: 288 pr_warn("Unrecognized mount option \"%s\" or missing value\n", 289 p); 290 return 0; 291 } 292 } 293 return 1; 294 } 295 296 /* This function definitely needs to be split up. Some fine day I'll 297 * hopefully have the guts to do so. Until then: sorry for the mess. 298 */ 299 300 static int affs_fill_super(struct super_block *sb, void *data, int silent) 301 { 302 struct affs_sb_info *sbi; 303 struct buffer_head *root_bh = NULL; 304 struct buffer_head *boot_bh; 305 struct inode *root_inode = NULL; 306 s32 root_block; 307 int size, blocksize; 308 u32 chksum; 309 int num_bm; 310 int i, j; 311 s32 key; 312 kuid_t uid; 313 kgid_t gid; 314 int reserved; 315 unsigned long mount_flags; 316 int tmp_flags; /* fix remount prototype... */ 317 u8 sig[4]; 318 int ret; 319 320 save_mount_options(sb, data); 321 322 pr_debug("read_super(%s)\n", data ? (const char *)data : "no options"); 323 324 sb->s_magic = AFFS_SUPER_MAGIC; 325 sb->s_op = &affs_sops; 326 sb->s_flags |= MS_NODIRATIME; 327 328 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL); 329 if (!sbi) 330 return -ENOMEM; 331 332 sb->s_fs_info = sbi; 333 sbi->sb = sb; 334 mutex_init(&sbi->s_bmlock); 335 spin_lock_init(&sbi->symlink_lock); 336 spin_lock_init(&sbi->work_lock); 337 INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock); 338 339 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block, 340 &blocksize,&sbi->s_prefix, 341 sbi->s_volume, &mount_flags)) { 342 pr_err("Error parsing options\n"); 343 return -EINVAL; 344 } 345 /* N.B. after this point s_prefix must be released */ 346 347 sbi->s_flags = mount_flags; 348 sbi->s_mode = i; 349 sbi->s_uid = uid; 350 sbi->s_gid = gid; 351 sbi->s_reserved= reserved; 352 353 /* Get the size of the device in 512-byte blocks. 354 * If we later see that the partition uses bigger 355 * blocks, we will have to change it. 356 */ 357 358 size = sb->s_bdev->bd_inode->i_size >> 9; 359 pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size); 360 361 affs_set_blocksize(sb, PAGE_SIZE); 362 /* Try to find root block. Its location depends on the block size. */ 363 364 i = 512; 365 j = 4096; 366 if (blocksize > 0) { 367 i = j = blocksize; 368 size = size / (blocksize / 512); 369 } 370 for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) { 371 sbi->s_root_block = root_block; 372 if (root_block < 0) 373 sbi->s_root_block = (reserved + size - 1) / 2; 374 pr_debug("setting blocksize to %d\n", blocksize); 375 affs_set_blocksize(sb, blocksize); 376 sbi->s_partition_size = size; 377 378 /* The root block location that was calculated above is not 379 * correct if the partition size is an odd number of 512- 380 * byte blocks, which will be rounded down to a number of 381 * 1024-byte blocks, and if there were an even number of 382 * reserved blocks. Ideally, all partition checkers should 383 * report the real number of blocks of the real blocksize, 384 * but since this just cannot be done, we have to try to 385 * find the root block anyways. In the above case, it is one 386 * block behind the calculated one. So we check this one, too. 387 */ 388 for (num_bm = 0; num_bm < 2; num_bm++) { 389 pr_debug("Dev %s, trying root=%u, bs=%d, " 390 "size=%d, reserved=%d\n", 391 sb->s_id, 392 sbi->s_root_block + num_bm, 393 blocksize, size, reserved); 394 root_bh = affs_bread(sb, sbi->s_root_block + num_bm); 395 if (!root_bh) 396 continue; 397 if (!affs_checksum_block(sb, root_bh) && 398 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT && 399 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) { 400 sbi->s_hashsize = blocksize / 4 - 56; 401 sbi->s_root_block += num_bm; 402 key = 1; 403 goto got_root; 404 } 405 affs_brelse(root_bh); 406 root_bh = NULL; 407 } 408 } 409 if (!silent) 410 pr_err("No valid root block on device %s\n", sb->s_id); 411 return -EINVAL; 412 413 /* N.B. after this point bh must be released */ 414 got_root: 415 /* Keep super block in cache */ 416 sbi->s_root_bh = root_bh; 417 root_block = sbi->s_root_block; 418 419 /* Find out which kind of FS we have */ 420 boot_bh = sb_bread(sb, 0); 421 if (!boot_bh) { 422 pr_err("Cannot read boot block\n"); 423 return -EINVAL; 424 } 425 memcpy(sig, boot_bh->b_data, 4); 426 brelse(boot_bh); 427 chksum = be32_to_cpu(*(__be32 *)sig); 428 429 /* Dircache filesystems are compatible with non-dircache ones 430 * when reading. As long as they aren't supported, writing is 431 * not recommended. 432 */ 433 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS 434 || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) { 435 pr_notice("Dircache FS - mounting %s read only\n", sb->s_id); 436 sb->s_flags |= MS_RDONLY; 437 } 438 switch (chksum) { 439 case MUFS_FS: 440 case MUFS_INTLFFS: 441 case MUFS_DCFFS: 442 sbi->s_flags |= SF_MUFS; 443 /* fall thru */ 444 case FS_INTLFFS: 445 case FS_DCFFS: 446 sbi->s_flags |= SF_INTL; 447 break; 448 case MUFS_FFS: 449 sbi->s_flags |= SF_MUFS; 450 break; 451 case FS_FFS: 452 break; 453 case MUFS_OFS: 454 sbi->s_flags |= SF_MUFS; 455 /* fall thru */ 456 case FS_OFS: 457 sbi->s_flags |= SF_OFS; 458 sb->s_flags |= MS_NOEXEC; 459 break; 460 case MUFS_DCOFS: 461 case MUFS_INTLOFS: 462 sbi->s_flags |= SF_MUFS; 463 case FS_DCOFS: 464 case FS_INTLOFS: 465 sbi->s_flags |= SF_INTL | SF_OFS; 466 sb->s_flags |= MS_NOEXEC; 467 break; 468 default: 469 pr_err("Unknown filesystem on device %s: %08X\n", 470 sb->s_id, chksum); 471 return -EINVAL; 472 } 473 474 if (mount_flags & SF_VERBOSE) { 475 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0]; 476 pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n", 477 len > 31 ? 31 : len, 478 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1, 479 sig, sig[3] + '0', blocksize); 480 } 481 482 sb->s_flags |= MS_NODEV | MS_NOSUID; 483 484 sbi->s_data_blksize = sb->s_blocksize; 485 if (sbi->s_flags & SF_OFS) 486 sbi->s_data_blksize -= 24; 487 488 tmp_flags = sb->s_flags; 489 ret = affs_init_bitmap(sb, &tmp_flags); 490 if (ret) 491 return ret; 492 sb->s_flags = tmp_flags; 493 494 /* set up enough so that it can read an inode */ 495 496 root_inode = affs_iget(sb, root_block); 497 if (IS_ERR(root_inode)) 498 return PTR_ERR(root_inode); 499 500 if (AFFS_SB(sb)->s_flags & SF_INTL) 501 sb->s_d_op = &affs_intl_dentry_operations; 502 else 503 sb->s_d_op = &affs_dentry_operations; 504 505 sb->s_root = d_make_root(root_inode); 506 if (!sb->s_root) { 507 pr_err("AFFS: Get root inode failed\n"); 508 return -ENOMEM; 509 } 510 511 pr_debug("s_flags=%lX\n", sb->s_flags); 512 return 0; 513 } 514 515 static int 516 affs_remount(struct super_block *sb, int *flags, char *data) 517 { 518 struct affs_sb_info *sbi = AFFS_SB(sb); 519 int blocksize; 520 kuid_t uid; 521 kgid_t gid; 522 int mode; 523 int reserved; 524 int root_block; 525 unsigned long mount_flags; 526 int res = 0; 527 char *new_opts = kstrdup(data, GFP_KERNEL); 528 char volume[32]; 529 char *prefix = NULL; 530 531 pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data); 532 533 sync_filesystem(sb); 534 *flags |= MS_NODIRATIME; 535 536 memcpy(volume, sbi->s_volume, 32); 537 if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block, 538 &blocksize, &prefix, volume, 539 &mount_flags)) { 540 kfree(prefix); 541 kfree(new_opts); 542 return -EINVAL; 543 } 544 545 flush_delayed_work(&sbi->sb_work); 546 replace_mount_options(sb, new_opts); 547 548 sbi->s_flags = mount_flags; 549 sbi->s_mode = mode; 550 sbi->s_uid = uid; 551 sbi->s_gid = gid; 552 /* protect against readers */ 553 spin_lock(&sbi->symlink_lock); 554 if (prefix) { 555 kfree(sbi->s_prefix); 556 sbi->s_prefix = prefix; 557 } 558 memcpy(sbi->s_volume, volume, 32); 559 spin_unlock(&sbi->symlink_lock); 560 561 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 562 return 0; 563 564 if (*flags & MS_RDONLY) 565 affs_free_bitmap(sb); 566 else 567 res = affs_init_bitmap(sb, flags); 568 569 return res; 570 } 571 572 static int 573 affs_statfs(struct dentry *dentry, struct kstatfs *buf) 574 { 575 struct super_block *sb = dentry->d_sb; 576 int free; 577 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 578 579 pr_debug("%s() partsize=%d, reserved=%d\n", 580 __func__, AFFS_SB(sb)->s_partition_size, 581 AFFS_SB(sb)->s_reserved); 582 583 free = affs_count_free_blocks(sb); 584 buf->f_type = AFFS_SUPER_MAGIC; 585 buf->f_bsize = sb->s_blocksize; 586 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved; 587 buf->f_bfree = free; 588 buf->f_bavail = free; 589 buf->f_fsid.val[0] = (u32)id; 590 buf->f_fsid.val[1] = (u32)(id >> 32); 591 buf->f_namelen = 30; 592 return 0; 593 } 594 595 static struct dentry *affs_mount(struct file_system_type *fs_type, 596 int flags, const char *dev_name, void *data) 597 { 598 return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super); 599 } 600 601 static void affs_kill_sb(struct super_block *sb) 602 { 603 struct affs_sb_info *sbi = AFFS_SB(sb); 604 kill_block_super(sb); 605 if (sbi) { 606 affs_free_bitmap(sb); 607 affs_brelse(sbi->s_root_bh); 608 kfree(sbi->s_prefix); 609 kfree(sbi); 610 } 611 } 612 613 static struct file_system_type affs_fs_type = { 614 .owner = THIS_MODULE, 615 .name = "affs", 616 .mount = affs_mount, 617 .kill_sb = affs_kill_sb, 618 .fs_flags = FS_REQUIRES_DEV, 619 }; 620 MODULE_ALIAS_FS("affs"); 621 622 static int __init init_affs_fs(void) 623 { 624 int err = init_inodecache(); 625 if (err) 626 goto out1; 627 err = register_filesystem(&affs_fs_type); 628 if (err) 629 goto out; 630 return 0; 631 out: 632 destroy_inodecache(); 633 out1: 634 return err; 635 } 636 637 static void __exit exit_affs_fs(void) 638 { 639 unregister_filesystem(&affs_fs_type); 640 destroy_inodecache(); 641 } 642 643 MODULE_DESCRIPTION("Amiga filesystem support for Linux"); 644 MODULE_LICENSE("GPL"); 645 646 module_init(init_affs_fs) 647 module_exit(exit_affs_fs) 648