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