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