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