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/cred.h> 20 #include <linux/slab.h> 21 #include <linux/writeback.h> 22 #include <linux/blkdev.h> 23 #include <linux/seq_file.h> 24 #include <linux/iversion.h> 25 #include "affs.h" 26 27 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf); 28 static int affs_show_options(struct seq_file *m, struct dentry *root); 29 static int affs_remount (struct super_block *sb, int *flags, char *data); 30 31 static void 32 affs_commit_super(struct super_block *sb, int wait) 33 { 34 struct affs_sb_info *sbi = AFFS_SB(sb); 35 struct buffer_head *bh = sbi->s_root_bh; 36 struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh); 37 38 lock_buffer(bh); 39 affs_secs_to_datestamp(ktime_get_real_seconds(), &tail->disk_change); 40 affs_fix_checksum(sb, bh); 41 unlock_buffer(bh); 42 43 mark_buffer_dirty(bh); 44 if (wait) 45 sync_dirty_buffer(bh); 46 } 47 48 static void 49 affs_put_super(struct super_block *sb) 50 { 51 struct affs_sb_info *sbi = AFFS_SB(sb); 52 pr_debug("%s()\n", __func__); 53 54 cancel_delayed_work_sync(&sbi->sb_work); 55 } 56 57 static int 58 affs_sync_fs(struct super_block *sb, int wait) 59 { 60 affs_commit_super(sb, wait); 61 return 0; 62 } 63 64 static void flush_superblock(struct work_struct *work) 65 { 66 struct affs_sb_info *sbi; 67 struct super_block *sb; 68 69 sbi = container_of(work, struct affs_sb_info, sb_work.work); 70 sb = sbi->sb; 71 72 spin_lock(&sbi->work_lock); 73 sbi->work_queued = 0; 74 spin_unlock(&sbi->work_lock); 75 76 affs_commit_super(sb, 1); 77 } 78 79 void affs_mark_sb_dirty(struct super_block *sb) 80 { 81 struct affs_sb_info *sbi = AFFS_SB(sb); 82 unsigned long delay; 83 84 if (sb_rdonly(sb)) 85 return; 86 87 spin_lock(&sbi->work_lock); 88 if (!sbi->work_queued) { 89 delay = msecs_to_jiffies(dirty_writeback_interval * 10); 90 queue_delayed_work(system_long_wq, &sbi->sb_work, delay); 91 sbi->work_queued = 1; 92 } 93 spin_unlock(&sbi->work_lock); 94 } 95 96 static struct kmem_cache * affs_inode_cachep; 97 98 static struct inode *affs_alloc_inode(struct super_block *sb) 99 { 100 struct affs_inode_info *i; 101 102 i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL); 103 if (!i) 104 return NULL; 105 106 inode_set_iversion(&i->vfs_inode, 1); 107 i->i_lc = NULL; 108 i->i_ext_bh = NULL; 109 i->i_pa_cnt = 0; 110 111 return &i->vfs_inode; 112 } 113 114 static void affs_free_inode(struct inode *inode) 115 { 116 kmem_cache_free(affs_inode_cachep, AFFS_I(inode)); 117 } 118 119 static void init_once(void *foo) 120 { 121 struct affs_inode_info *ei = (struct affs_inode_info *) foo; 122 123 sema_init(&ei->i_link_lock, 1); 124 sema_init(&ei->i_ext_lock, 1); 125 inode_init_once(&ei->vfs_inode); 126 } 127 128 static int __init init_inodecache(void) 129 { 130 affs_inode_cachep = kmem_cache_create("affs_inode_cache", 131 sizeof(struct affs_inode_info), 132 0, (SLAB_RECLAIM_ACCOUNT| 133 SLAB_MEM_SPREAD|SLAB_ACCOUNT), 134 init_once); 135 if (affs_inode_cachep == NULL) 136 return -ENOMEM; 137 return 0; 138 } 139 140 static void destroy_inodecache(void) 141 { 142 /* 143 * Make sure all delayed rcu free inodes are flushed before we 144 * destroy cache. 145 */ 146 rcu_barrier(); 147 kmem_cache_destroy(affs_inode_cachep); 148 } 149 150 static const struct super_operations affs_sops = { 151 .alloc_inode = affs_alloc_inode, 152 .free_inode = affs_free_inode, 153 .write_inode = affs_write_inode, 154 .evict_inode = affs_evict_inode, 155 .put_super = affs_put_super, 156 .sync_fs = affs_sync_fs, 157 .statfs = affs_statfs, 158 .remount_fs = affs_remount, 159 .show_options = affs_show_options, 160 }; 161 162 enum { 163 Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect, 164 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid, 165 Opt_verbose, Opt_volume, Opt_ignore, Opt_err, 166 }; 167 168 static const match_table_t tokens = { 169 {Opt_bs, "bs=%u"}, 170 {Opt_mode, "mode=%o"}, 171 {Opt_mufs, "mufs"}, 172 {Opt_notruncate, "nofilenametruncate"}, 173 {Opt_prefix, "prefix=%s"}, 174 {Opt_protect, "protect"}, 175 {Opt_reserved, "reserved=%u"}, 176 {Opt_root, "root=%u"}, 177 {Opt_setgid, "setgid=%u"}, 178 {Opt_setuid, "setuid=%u"}, 179 {Opt_verbose, "verbose"}, 180 {Opt_volume, "volume=%s"}, 181 {Opt_ignore, "grpquota"}, 182 {Opt_ignore, "noquota"}, 183 {Opt_ignore, "quota"}, 184 {Opt_ignore, "usrquota"}, 185 {Opt_err, NULL}, 186 }; 187 188 static int 189 parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root, 190 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts) 191 { 192 char *p; 193 substring_t args[MAX_OPT_ARGS]; 194 195 /* Fill in defaults */ 196 197 *uid = current_uid(); 198 *gid = current_gid(); 199 *reserved = 2; 200 *root = -1; 201 *blocksize = -1; 202 volume[0] = ':'; 203 volume[1] = 0; 204 *mount_opts = 0; 205 if (!options) 206 return 1; 207 208 while ((p = strsep(&options, ",")) != NULL) { 209 int token, n, option; 210 if (!*p) 211 continue; 212 213 token = match_token(p, tokens, args); 214 switch (token) { 215 case Opt_bs: 216 if (match_int(&args[0], &n)) 217 return 0; 218 if (n != 512 && n != 1024 && n != 2048 219 && n != 4096) { 220 pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n"); 221 return 0; 222 } 223 *blocksize = n; 224 break; 225 case Opt_mode: 226 if (match_octal(&args[0], &option)) 227 return 0; 228 *mode = option & 0777; 229 affs_set_opt(*mount_opts, SF_SETMODE); 230 break; 231 case Opt_mufs: 232 affs_set_opt(*mount_opts, SF_MUFS); 233 break; 234 case Opt_notruncate: 235 affs_set_opt(*mount_opts, SF_NO_TRUNCATE); 236 break; 237 case Opt_prefix: 238 kfree(*prefix); 239 *prefix = match_strdup(&args[0]); 240 if (!*prefix) 241 return 0; 242 affs_set_opt(*mount_opts, SF_PREFIX); 243 break; 244 case Opt_protect: 245 affs_set_opt(*mount_opts, SF_IMMUTABLE); 246 break; 247 case Opt_reserved: 248 if (match_int(&args[0], reserved)) 249 return 0; 250 break; 251 case Opt_root: 252 if (match_int(&args[0], root)) 253 return 0; 254 break; 255 case Opt_setgid: 256 if (match_int(&args[0], &option)) 257 return 0; 258 *gid = make_kgid(current_user_ns(), option); 259 if (!gid_valid(*gid)) 260 return 0; 261 affs_set_opt(*mount_opts, SF_SETGID); 262 break; 263 case Opt_setuid: 264 if (match_int(&args[0], &option)) 265 return 0; 266 *uid = make_kuid(current_user_ns(), option); 267 if (!uid_valid(*uid)) 268 return 0; 269 affs_set_opt(*mount_opts, SF_SETUID); 270 break; 271 case Opt_verbose: 272 affs_set_opt(*mount_opts, SF_VERBOSE); 273 break; 274 case Opt_volume: { 275 char *vol = match_strdup(&args[0]); 276 if (!vol) 277 return 0; 278 strlcpy(volume, vol, 32); 279 kfree(vol); 280 break; 281 } 282 case Opt_ignore: 283 /* Silently ignore the quota options */ 284 break; 285 default: 286 pr_warn("Unrecognized mount option \"%s\" or missing value\n", 287 p); 288 return 0; 289 } 290 } 291 return 1; 292 } 293 294 static int affs_show_options(struct seq_file *m, struct dentry *root) 295 { 296 struct super_block *sb = root->d_sb; 297 struct affs_sb_info *sbi = AFFS_SB(sb); 298 299 if (sb->s_blocksize) 300 seq_printf(m, ",bs=%lu", sb->s_blocksize); 301 if (affs_test_opt(sbi->s_flags, SF_SETMODE)) 302 seq_printf(m, ",mode=%o", sbi->s_mode); 303 if (affs_test_opt(sbi->s_flags, SF_MUFS)) 304 seq_puts(m, ",mufs"); 305 if (affs_test_opt(sbi->s_flags, SF_NO_TRUNCATE)) 306 seq_puts(m, ",nofilenametruncate"); 307 if (affs_test_opt(sbi->s_flags, SF_PREFIX)) 308 seq_printf(m, ",prefix=%s", sbi->s_prefix); 309 if (affs_test_opt(sbi->s_flags, SF_IMMUTABLE)) 310 seq_puts(m, ",protect"); 311 if (sbi->s_reserved != 2) 312 seq_printf(m, ",reserved=%u", sbi->s_reserved); 313 if (sbi->s_root_block != (sbi->s_reserved + sbi->s_partition_size - 1) / 2) 314 seq_printf(m, ",root=%u", sbi->s_root_block); 315 if (affs_test_opt(sbi->s_flags, SF_SETGID)) 316 seq_printf(m, ",setgid=%u", 317 from_kgid_munged(&init_user_ns, sbi->s_gid)); 318 if (affs_test_opt(sbi->s_flags, SF_SETUID)) 319 seq_printf(m, ",setuid=%u", 320 from_kuid_munged(&init_user_ns, sbi->s_uid)); 321 if (affs_test_opt(sbi->s_flags, SF_VERBOSE)) 322 seq_puts(m, ",verbose"); 323 if (sbi->s_volume[0]) 324 seq_printf(m, ",volume=%s", sbi->s_volume); 325 return 0; 326 } 327 328 /* This function definitely needs to be split up. Some fine day I'll 329 * hopefully have the guts to do so. Until then: sorry for the mess. 330 */ 331 332 static int affs_fill_super(struct super_block *sb, void *data, int silent) 333 { 334 struct affs_sb_info *sbi; 335 struct buffer_head *root_bh = NULL; 336 struct buffer_head *boot_bh; 337 struct inode *root_inode = NULL; 338 s32 root_block; 339 int size, blocksize; 340 u32 chksum; 341 int num_bm; 342 int i, j; 343 kuid_t uid; 344 kgid_t gid; 345 int reserved; 346 unsigned long mount_flags; 347 int tmp_flags; /* fix remount prototype... */ 348 u8 sig[4]; 349 int ret; 350 351 pr_debug("read_super(%s)\n", data ? (const char *)data : "no options"); 352 353 sb->s_magic = AFFS_SUPER_MAGIC; 354 sb->s_op = &affs_sops; 355 sb->s_flags |= SB_NODIRATIME; 356 357 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL); 358 if (!sbi) 359 return -ENOMEM; 360 361 sb->s_fs_info = sbi; 362 sbi->sb = sb; 363 mutex_init(&sbi->s_bmlock); 364 spin_lock_init(&sbi->symlink_lock); 365 spin_lock_init(&sbi->work_lock); 366 INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock); 367 368 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block, 369 &blocksize,&sbi->s_prefix, 370 sbi->s_volume, &mount_flags)) { 371 pr_err("Error parsing options\n"); 372 return -EINVAL; 373 } 374 /* N.B. after this point s_prefix must be released */ 375 376 sbi->s_flags = mount_flags; 377 sbi->s_mode = i; 378 sbi->s_uid = uid; 379 sbi->s_gid = gid; 380 sbi->s_reserved= reserved; 381 382 /* Get the size of the device in 512-byte blocks. 383 * If we later see that the partition uses bigger 384 * blocks, we will have to change it. 385 */ 386 387 size = i_size_read(sb->s_bdev->bd_inode) >> 9; 388 pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size); 389 390 affs_set_blocksize(sb, PAGE_SIZE); 391 /* Try to find root block. Its location depends on the block size. */ 392 393 i = bdev_logical_block_size(sb->s_bdev); 394 j = PAGE_SIZE; 395 if (blocksize > 0) { 396 i = j = blocksize; 397 size = size / (blocksize / 512); 398 } 399 400 for (blocksize = i; blocksize <= j; blocksize <<= 1, size >>= 1) { 401 sbi->s_root_block = root_block; 402 if (root_block < 0) 403 sbi->s_root_block = (reserved + size - 1) / 2; 404 pr_debug("setting blocksize to %d\n", blocksize); 405 affs_set_blocksize(sb, blocksize); 406 sbi->s_partition_size = size; 407 408 /* The root block location that was calculated above is not 409 * correct if the partition size is an odd number of 512- 410 * byte blocks, which will be rounded down to a number of 411 * 1024-byte blocks, and if there were an even number of 412 * reserved blocks. Ideally, all partition checkers should 413 * report the real number of blocks of the real blocksize, 414 * but since this just cannot be done, we have to try to 415 * find the root block anyways. In the above case, it is one 416 * block behind the calculated one. So we check this one, too. 417 */ 418 for (num_bm = 0; num_bm < 2; num_bm++) { 419 pr_debug("Dev %s, trying root=%u, bs=%d, " 420 "size=%d, reserved=%d\n", 421 sb->s_id, 422 sbi->s_root_block + num_bm, 423 blocksize, size, reserved); 424 root_bh = affs_bread(sb, sbi->s_root_block + num_bm); 425 if (!root_bh) 426 continue; 427 if (!affs_checksum_block(sb, root_bh) && 428 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT && 429 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) { 430 sbi->s_hashsize = blocksize / 4 - 56; 431 sbi->s_root_block += num_bm; 432 goto got_root; 433 } 434 affs_brelse(root_bh); 435 root_bh = NULL; 436 } 437 } 438 if (!silent) 439 pr_err("No valid root block on device %s\n", sb->s_id); 440 return -EINVAL; 441 442 /* N.B. after this point bh must be released */ 443 got_root: 444 /* Keep super block in cache */ 445 sbi->s_root_bh = root_bh; 446 root_block = sbi->s_root_block; 447 448 /* Find out which kind of FS we have */ 449 boot_bh = sb_bread(sb, 0); 450 if (!boot_bh) { 451 pr_err("Cannot read boot block\n"); 452 return -EINVAL; 453 } 454 memcpy(sig, boot_bh->b_data, 4); 455 brelse(boot_bh); 456 chksum = be32_to_cpu(*(__be32 *)sig); 457 458 /* Dircache filesystems are compatible with non-dircache ones 459 * when reading. As long as they aren't supported, writing is 460 * not recommended. 461 */ 462 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS 463 || chksum == MUFS_DCOFS) && !sb_rdonly(sb)) { 464 pr_notice("Dircache FS - mounting %s read only\n", sb->s_id); 465 sb->s_flags |= SB_RDONLY; 466 } 467 switch (chksum) { 468 case MUFS_FS: 469 case MUFS_INTLFFS: 470 case MUFS_DCFFS: 471 affs_set_opt(sbi->s_flags, SF_MUFS); 472 /* fall thru */ 473 case FS_INTLFFS: 474 case FS_DCFFS: 475 affs_set_opt(sbi->s_flags, SF_INTL); 476 break; 477 case MUFS_FFS: 478 affs_set_opt(sbi->s_flags, SF_MUFS); 479 break; 480 case FS_FFS: 481 break; 482 case MUFS_OFS: 483 affs_set_opt(sbi->s_flags, SF_MUFS); 484 /* fall through */ 485 case FS_OFS: 486 affs_set_opt(sbi->s_flags, SF_OFS); 487 sb->s_flags |= SB_NOEXEC; 488 break; 489 case MUFS_DCOFS: 490 case MUFS_INTLOFS: 491 affs_set_opt(sbi->s_flags, SF_MUFS); 492 /* fall through */ 493 case FS_DCOFS: 494 case FS_INTLOFS: 495 affs_set_opt(sbi->s_flags, SF_INTL); 496 affs_set_opt(sbi->s_flags, SF_OFS); 497 sb->s_flags |= SB_NOEXEC; 498 break; 499 default: 500 pr_err("Unknown filesystem on device %s: %08X\n", 501 sb->s_id, chksum); 502 return -EINVAL; 503 } 504 505 if (affs_test_opt(mount_flags, SF_VERBOSE)) { 506 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0]; 507 pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n", 508 len > 31 ? 31 : len, 509 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1, 510 sig, sig[3] + '0', blocksize); 511 } 512 513 sb->s_flags |= SB_NODEV | SB_NOSUID; 514 515 sbi->s_data_blksize = sb->s_blocksize; 516 if (affs_test_opt(sbi->s_flags, SF_OFS)) 517 sbi->s_data_blksize -= 24; 518 519 tmp_flags = sb->s_flags; 520 ret = affs_init_bitmap(sb, &tmp_flags); 521 if (ret) 522 return ret; 523 sb->s_flags = tmp_flags; 524 525 /* set up enough so that it can read an inode */ 526 527 root_inode = affs_iget(sb, root_block); 528 if (IS_ERR(root_inode)) 529 return PTR_ERR(root_inode); 530 531 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL)) 532 sb->s_d_op = &affs_intl_dentry_operations; 533 else 534 sb->s_d_op = &affs_dentry_operations; 535 536 sb->s_root = d_make_root(root_inode); 537 if (!sb->s_root) { 538 pr_err("AFFS: Get root inode failed\n"); 539 return -ENOMEM; 540 } 541 542 sb->s_export_op = &affs_export_ops; 543 pr_debug("s_flags=%lX\n", sb->s_flags); 544 return 0; 545 } 546 547 static int 548 affs_remount(struct super_block *sb, int *flags, char *data) 549 { 550 struct affs_sb_info *sbi = AFFS_SB(sb); 551 int blocksize; 552 kuid_t uid; 553 kgid_t gid; 554 int mode; 555 int reserved; 556 int root_block; 557 unsigned long mount_flags; 558 int res = 0; 559 char *new_opts; 560 char volume[32]; 561 char *prefix = NULL; 562 563 new_opts = kstrdup(data, GFP_KERNEL); 564 if (data && !new_opts) 565 return -ENOMEM; 566 567 pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data); 568 569 sync_filesystem(sb); 570 *flags |= SB_NODIRATIME; 571 572 memcpy(volume, sbi->s_volume, 32); 573 if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block, 574 &blocksize, &prefix, volume, 575 &mount_flags)) { 576 kfree(prefix); 577 kfree(new_opts); 578 return -EINVAL; 579 } 580 581 flush_delayed_work(&sbi->sb_work); 582 583 sbi->s_flags = mount_flags; 584 sbi->s_mode = mode; 585 sbi->s_uid = uid; 586 sbi->s_gid = gid; 587 /* protect against readers */ 588 spin_lock(&sbi->symlink_lock); 589 if (prefix) { 590 kfree(sbi->s_prefix); 591 sbi->s_prefix = prefix; 592 } 593 memcpy(sbi->s_volume, volume, 32); 594 spin_unlock(&sbi->symlink_lock); 595 596 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) 597 return 0; 598 599 if (*flags & SB_RDONLY) 600 affs_free_bitmap(sb); 601 else 602 res = affs_init_bitmap(sb, flags); 603 604 return res; 605 } 606 607 static int 608 affs_statfs(struct dentry *dentry, struct kstatfs *buf) 609 { 610 struct super_block *sb = dentry->d_sb; 611 int free; 612 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 613 614 pr_debug("%s() partsize=%d, reserved=%d\n", 615 __func__, AFFS_SB(sb)->s_partition_size, 616 AFFS_SB(sb)->s_reserved); 617 618 free = affs_count_free_blocks(sb); 619 buf->f_type = AFFS_SUPER_MAGIC; 620 buf->f_bsize = sb->s_blocksize; 621 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved; 622 buf->f_bfree = free; 623 buf->f_bavail = free; 624 buf->f_fsid.val[0] = (u32)id; 625 buf->f_fsid.val[1] = (u32)(id >> 32); 626 buf->f_namelen = AFFSNAMEMAX; 627 return 0; 628 } 629 630 static struct dentry *affs_mount(struct file_system_type *fs_type, 631 int flags, const char *dev_name, void *data) 632 { 633 return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super); 634 } 635 636 static void affs_kill_sb(struct super_block *sb) 637 { 638 struct affs_sb_info *sbi = AFFS_SB(sb); 639 kill_block_super(sb); 640 if (sbi) { 641 affs_free_bitmap(sb); 642 affs_brelse(sbi->s_root_bh); 643 kfree(sbi->s_prefix); 644 mutex_destroy(&sbi->s_bmlock); 645 kfree(sbi); 646 } 647 } 648 649 static struct file_system_type affs_fs_type = { 650 .owner = THIS_MODULE, 651 .name = "affs", 652 .mount = affs_mount, 653 .kill_sb = affs_kill_sb, 654 .fs_flags = FS_REQUIRES_DEV, 655 }; 656 MODULE_ALIAS_FS("affs"); 657 658 static int __init init_affs_fs(void) 659 { 660 int err = init_inodecache(); 661 if (err) 662 goto out1; 663 err = register_filesystem(&affs_fs_type); 664 if (err) 665 goto out; 666 return 0; 667 out: 668 destroy_inodecache(); 669 out1: 670 return err; 671 } 672 673 static void __exit exit_affs_fs(void) 674 { 675 unregister_filesystem(&affs_fs_type); 676 destroy_inodecache(); 677 } 678 679 MODULE_DESCRIPTION("Amiga filesystem support for Linux"); 680 MODULE_LICENSE("GPL"); 681 682 module_init(init_affs_fs) 683 module_exit(exit_affs_fs) 684