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 "affs.h" 21 22 extern struct timezone sys_tz; 23 24 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf); 25 static int affs_remount (struct super_block *sb, int *flags, char *data); 26 27 static void 28 affs_commit_super(struct super_block *sb, int wait, int clean) 29 { 30 struct affs_sb_info *sbi = AFFS_SB(sb); 31 struct buffer_head *bh = sbi->s_root_bh; 32 struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh); 33 34 tail->bm_flag = cpu_to_be32(clean); 35 secs_to_datestamp(get_seconds(), &tail->disk_change); 36 affs_fix_checksum(sb, bh); 37 mark_buffer_dirty(bh); 38 if (wait) 39 sync_dirty_buffer(bh); 40 } 41 42 static void 43 affs_put_super(struct super_block *sb) 44 { 45 struct affs_sb_info *sbi = AFFS_SB(sb); 46 pr_debug("AFFS: put_super()\n"); 47 48 if (!(sb->s_flags & MS_RDONLY) && sb->s_dirt) 49 affs_commit_super(sb, 1, 1); 50 51 kfree(sbi->s_prefix); 52 affs_free_bitmap(sb); 53 affs_brelse(sbi->s_root_bh); 54 kfree(sbi); 55 sb->s_fs_info = NULL; 56 } 57 58 static void 59 affs_write_super(struct super_block *sb) 60 { 61 lock_super(sb); 62 if (!(sb->s_flags & MS_RDONLY)) 63 affs_commit_super(sb, 1, 2); 64 sb->s_dirt = 0; 65 unlock_super(sb); 66 67 pr_debug("AFFS: write_super() at %lu, clean=2\n", get_seconds()); 68 } 69 70 static int 71 affs_sync_fs(struct super_block *sb, int wait) 72 { 73 lock_super(sb); 74 affs_commit_super(sb, wait, 2); 75 sb->s_dirt = 0; 76 unlock_super(sb); 77 return 0; 78 } 79 80 static struct kmem_cache * affs_inode_cachep; 81 82 static struct inode *affs_alloc_inode(struct super_block *sb) 83 { 84 struct affs_inode_info *i; 85 86 i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL); 87 if (!i) 88 return NULL; 89 90 i->vfs_inode.i_version = 1; 91 i->i_lc = NULL; 92 i->i_ext_bh = NULL; 93 i->i_pa_cnt = 0; 94 95 return &i->vfs_inode; 96 } 97 98 static void affs_i_callback(struct rcu_head *head) 99 { 100 struct inode *inode = container_of(head, struct inode, i_rcu); 101 kmem_cache_free(affs_inode_cachep, AFFS_I(inode)); 102 } 103 104 static void affs_destroy_inode(struct inode *inode) 105 { 106 call_rcu(&inode->i_rcu, affs_i_callback); 107 } 108 109 static void init_once(void *foo) 110 { 111 struct affs_inode_info *ei = (struct affs_inode_info *) foo; 112 113 sema_init(&ei->i_link_lock, 1); 114 sema_init(&ei->i_ext_lock, 1); 115 inode_init_once(&ei->vfs_inode); 116 } 117 118 static int init_inodecache(void) 119 { 120 affs_inode_cachep = kmem_cache_create("affs_inode_cache", 121 sizeof(struct affs_inode_info), 122 0, (SLAB_RECLAIM_ACCOUNT| 123 SLAB_MEM_SPREAD), 124 init_once); 125 if (affs_inode_cachep == NULL) 126 return -ENOMEM; 127 return 0; 128 } 129 130 static void destroy_inodecache(void) 131 { 132 kmem_cache_destroy(affs_inode_cachep); 133 } 134 135 static const struct super_operations affs_sops = { 136 .alloc_inode = affs_alloc_inode, 137 .destroy_inode = affs_destroy_inode, 138 .write_inode = affs_write_inode, 139 .evict_inode = affs_evict_inode, 140 .put_super = affs_put_super, 141 .write_super = affs_write_super, 142 .sync_fs = affs_sync_fs, 143 .statfs = affs_statfs, 144 .remount_fs = affs_remount, 145 .show_options = generic_show_options, 146 }; 147 148 enum { 149 Opt_bs, Opt_mode, Opt_mufs, Opt_prefix, Opt_protect, 150 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid, 151 Opt_verbose, Opt_volume, Opt_ignore, Opt_err, 152 }; 153 154 static const match_table_t tokens = { 155 {Opt_bs, "bs=%u"}, 156 {Opt_mode, "mode=%o"}, 157 {Opt_mufs, "mufs"}, 158 {Opt_prefix, "prefix=%s"}, 159 {Opt_protect, "protect"}, 160 {Opt_reserved, "reserved=%u"}, 161 {Opt_root, "root=%u"}, 162 {Opt_setgid, "setgid=%u"}, 163 {Opt_setuid, "setuid=%u"}, 164 {Opt_verbose, "verbose"}, 165 {Opt_volume, "volume=%s"}, 166 {Opt_ignore, "grpquota"}, 167 {Opt_ignore, "noquota"}, 168 {Opt_ignore, "quota"}, 169 {Opt_ignore, "usrquota"}, 170 {Opt_err, NULL}, 171 }; 172 173 static int 174 parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root, 175 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts) 176 { 177 char *p; 178 substring_t args[MAX_OPT_ARGS]; 179 180 /* Fill in defaults */ 181 182 *uid = current_uid(); 183 *gid = current_gid(); 184 *reserved = 2; 185 *root = -1; 186 *blocksize = -1; 187 volume[0] = ':'; 188 volume[1] = 0; 189 *mount_opts = 0; 190 if (!options) 191 return 1; 192 193 while ((p = strsep(&options, ",")) != NULL) { 194 int token, n, option; 195 if (!*p) 196 continue; 197 198 token = match_token(p, tokens, args); 199 switch (token) { 200 case Opt_bs: 201 if (match_int(&args[0], &n)) 202 return 0; 203 if (n != 512 && n != 1024 && n != 2048 204 && n != 4096) { 205 printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n"); 206 return 0; 207 } 208 *blocksize = n; 209 break; 210 case Opt_mode: 211 if (match_octal(&args[0], &option)) 212 return 0; 213 *mode = option & 0777; 214 *mount_opts |= SF_SETMODE; 215 break; 216 case Opt_mufs: 217 *mount_opts |= SF_MUFS; 218 break; 219 case Opt_prefix: 220 *prefix = match_strdup(&args[0]); 221 if (!*prefix) 222 return 0; 223 *mount_opts |= SF_PREFIX; 224 break; 225 case Opt_protect: 226 *mount_opts |= SF_IMMUTABLE; 227 break; 228 case Opt_reserved: 229 if (match_int(&args[0], reserved)) 230 return 0; 231 break; 232 case Opt_root: 233 if (match_int(&args[0], root)) 234 return 0; 235 break; 236 case Opt_setgid: 237 if (match_int(&args[0], &option)) 238 return 0; 239 *gid = option; 240 *mount_opts |= SF_SETGID; 241 break; 242 case Opt_setuid: 243 if (match_int(&args[0], &option)) 244 return 0; 245 *uid = option; 246 *mount_opts |= SF_SETUID; 247 break; 248 case Opt_verbose: 249 *mount_opts |= SF_VERBOSE; 250 break; 251 case Opt_volume: { 252 char *vol = match_strdup(&args[0]); 253 if (!vol) 254 return 0; 255 strlcpy(volume, vol, 32); 256 kfree(vol); 257 break; 258 } 259 case Opt_ignore: 260 /* Silently ignore the quota options */ 261 break; 262 default: 263 printk("AFFS: Unrecognized mount option \"%s\" " 264 "or missing value\n", p); 265 return 0; 266 } 267 } 268 return 1; 269 } 270 271 /* This function definitely needs to be split up. Some fine day I'll 272 * hopefully have the guts to do so. Until then: sorry for the mess. 273 */ 274 275 static int affs_fill_super(struct super_block *sb, void *data, int silent) 276 { 277 struct affs_sb_info *sbi; 278 struct buffer_head *root_bh = NULL; 279 struct buffer_head *boot_bh; 280 struct inode *root_inode = NULL; 281 s32 root_block; 282 int size, blocksize; 283 u32 chksum; 284 int num_bm; 285 int i, j; 286 s32 key; 287 uid_t uid; 288 gid_t gid; 289 int reserved; 290 unsigned long mount_flags; 291 int tmp_flags; /* fix remount prototype... */ 292 u8 sig[4]; 293 int ret = -EINVAL; 294 295 save_mount_options(sb, data); 296 297 pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options"); 298 299 sb->s_magic = AFFS_SUPER_MAGIC; 300 sb->s_op = &affs_sops; 301 sb->s_flags |= MS_NODIRATIME; 302 303 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL); 304 if (!sbi) 305 return -ENOMEM; 306 307 sb->s_fs_info = sbi; 308 mutex_init(&sbi->s_bmlock); 309 spin_lock_init(&sbi->symlink_lock); 310 311 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block, 312 &blocksize,&sbi->s_prefix, 313 sbi->s_volume, &mount_flags)) { 314 printk(KERN_ERR "AFFS: Error parsing options\n"); 315 kfree(sbi->s_prefix); 316 kfree(sbi); 317 return -EINVAL; 318 } 319 /* N.B. after this point s_prefix must be released */ 320 321 sbi->s_flags = mount_flags; 322 sbi->s_mode = i; 323 sbi->s_uid = uid; 324 sbi->s_gid = gid; 325 sbi->s_reserved= reserved; 326 327 /* Get the size of the device in 512-byte blocks. 328 * If we later see that the partition uses bigger 329 * blocks, we will have to change it. 330 */ 331 332 size = sb->s_bdev->bd_inode->i_size >> 9; 333 pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size); 334 335 affs_set_blocksize(sb, PAGE_SIZE); 336 /* Try to find root block. Its location depends on the block size. */ 337 338 i = 512; 339 j = 4096; 340 if (blocksize > 0) { 341 i = j = blocksize; 342 size = size / (blocksize / 512); 343 } 344 for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) { 345 sbi->s_root_block = root_block; 346 if (root_block < 0) 347 sbi->s_root_block = (reserved + size - 1) / 2; 348 pr_debug("AFFS: setting blocksize to %d\n", blocksize); 349 affs_set_blocksize(sb, blocksize); 350 sbi->s_partition_size = size; 351 352 /* The root block location that was calculated above is not 353 * correct if the partition size is an odd number of 512- 354 * byte blocks, which will be rounded down to a number of 355 * 1024-byte blocks, and if there were an even number of 356 * reserved blocks. Ideally, all partition checkers should 357 * report the real number of blocks of the real blocksize, 358 * but since this just cannot be done, we have to try to 359 * find the root block anyways. In the above case, it is one 360 * block behind the calculated one. So we check this one, too. 361 */ 362 for (num_bm = 0; num_bm < 2; num_bm++) { 363 pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, " 364 "size=%d, reserved=%d\n", 365 sb->s_id, 366 sbi->s_root_block + num_bm, 367 blocksize, size, reserved); 368 root_bh = affs_bread(sb, sbi->s_root_block + num_bm); 369 if (!root_bh) 370 continue; 371 if (!affs_checksum_block(sb, root_bh) && 372 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT && 373 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) { 374 sbi->s_hashsize = blocksize / 4 - 56; 375 sbi->s_root_block += num_bm; 376 key = 1; 377 goto got_root; 378 } 379 affs_brelse(root_bh); 380 root_bh = NULL; 381 } 382 } 383 if (!silent) 384 printk(KERN_ERR "AFFS: No valid root block on device %s\n", 385 sb->s_id); 386 goto out_error; 387 388 /* N.B. after this point bh must be released */ 389 got_root: 390 root_block = sbi->s_root_block; 391 392 /* Find out which kind of FS we have */ 393 boot_bh = sb_bread(sb, 0); 394 if (!boot_bh) { 395 printk(KERN_ERR "AFFS: Cannot read boot block\n"); 396 goto out_error; 397 } 398 memcpy(sig, boot_bh->b_data, 4); 399 brelse(boot_bh); 400 chksum = be32_to_cpu(*(__be32 *)sig); 401 402 /* Dircache filesystems are compatible with non-dircache ones 403 * when reading. As long as they aren't supported, writing is 404 * not recommended. 405 */ 406 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS 407 || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) { 408 printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n", 409 sb->s_id); 410 sb->s_flags |= MS_RDONLY; 411 } 412 switch (chksum) { 413 case MUFS_FS: 414 case MUFS_INTLFFS: 415 case MUFS_DCFFS: 416 sbi->s_flags |= SF_MUFS; 417 /* fall thru */ 418 case FS_INTLFFS: 419 case FS_DCFFS: 420 sbi->s_flags |= SF_INTL; 421 break; 422 case MUFS_FFS: 423 sbi->s_flags |= SF_MUFS; 424 break; 425 case FS_FFS: 426 break; 427 case MUFS_OFS: 428 sbi->s_flags |= SF_MUFS; 429 /* fall thru */ 430 case FS_OFS: 431 sbi->s_flags |= SF_OFS; 432 sb->s_flags |= MS_NOEXEC; 433 break; 434 case MUFS_DCOFS: 435 case MUFS_INTLOFS: 436 sbi->s_flags |= SF_MUFS; 437 case FS_DCOFS: 438 case FS_INTLOFS: 439 sbi->s_flags |= SF_INTL | SF_OFS; 440 sb->s_flags |= MS_NOEXEC; 441 break; 442 default: 443 printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n", 444 sb->s_id, chksum); 445 goto out_error; 446 } 447 448 if (mount_flags & SF_VERBOSE) { 449 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0]; 450 printk(KERN_NOTICE "AFFS: Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n", 451 len > 31 ? 31 : len, 452 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1, 453 sig, sig[3] + '0', blocksize); 454 } 455 456 sb->s_flags |= MS_NODEV | MS_NOSUID; 457 458 sbi->s_data_blksize = sb->s_blocksize; 459 if (sbi->s_flags & SF_OFS) 460 sbi->s_data_blksize -= 24; 461 462 /* Keep super block in cache */ 463 sbi->s_root_bh = root_bh; 464 /* N.B. after this point s_root_bh must be released */ 465 466 tmp_flags = sb->s_flags; 467 if (affs_init_bitmap(sb, &tmp_flags)) 468 goto out_error; 469 sb->s_flags = tmp_flags; 470 471 /* set up enough so that it can read an inode */ 472 473 root_inode = affs_iget(sb, root_block); 474 if (IS_ERR(root_inode)) { 475 ret = PTR_ERR(root_inode); 476 goto out_error; 477 } 478 479 if (AFFS_SB(sb)->s_flags & SF_INTL) 480 sb->s_d_op = &affs_intl_dentry_operations; 481 else 482 sb->s_d_op = &affs_dentry_operations; 483 484 sb->s_root = d_make_root(root_inode); 485 if (!sb->s_root) { 486 printk(KERN_ERR "AFFS: Get root inode failed\n"); 487 goto out_error; 488 } 489 490 pr_debug("AFFS: s_flags=%lX\n",sb->s_flags); 491 return 0; 492 493 /* 494 * Begin the cascaded cleanup ... 495 */ 496 out_error: 497 kfree(sbi->s_bitmap); 498 affs_brelse(root_bh); 499 kfree(sbi->s_prefix); 500 kfree(sbi); 501 sb->s_fs_info = NULL; 502 return ret; 503 } 504 505 static int 506 affs_remount(struct super_block *sb, int *flags, char *data) 507 { 508 struct affs_sb_info *sbi = AFFS_SB(sb); 509 int blocksize; 510 uid_t uid; 511 gid_t gid; 512 int mode; 513 int reserved; 514 int root_block; 515 unsigned long mount_flags; 516 int res = 0; 517 char *new_opts = kstrdup(data, GFP_KERNEL); 518 char volume[32]; 519 char *prefix = NULL; 520 521 pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data); 522 523 *flags |= MS_NODIRATIME; 524 525 memcpy(volume, sbi->s_volume, 32); 526 if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block, 527 &blocksize, &prefix, volume, 528 &mount_flags)) { 529 kfree(prefix); 530 kfree(new_opts); 531 return -EINVAL; 532 } 533 534 replace_mount_options(sb, new_opts); 535 536 sbi->s_flags = mount_flags; 537 sbi->s_mode = mode; 538 sbi->s_uid = uid; 539 sbi->s_gid = gid; 540 /* protect against readers */ 541 spin_lock(&sbi->symlink_lock); 542 if (prefix) { 543 kfree(sbi->s_prefix); 544 sbi->s_prefix = prefix; 545 } 546 memcpy(sbi->s_volume, volume, 32); 547 spin_unlock(&sbi->symlink_lock); 548 549 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 550 return 0; 551 552 if (*flags & MS_RDONLY) { 553 affs_write_super(sb); 554 affs_free_bitmap(sb); 555 } else 556 res = affs_init_bitmap(sb, flags); 557 558 return res; 559 } 560 561 static int 562 affs_statfs(struct dentry *dentry, struct kstatfs *buf) 563 { 564 struct super_block *sb = dentry->d_sb; 565 int free; 566 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 567 568 pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size, 569 AFFS_SB(sb)->s_reserved); 570 571 free = affs_count_free_blocks(sb); 572 buf->f_type = AFFS_SUPER_MAGIC; 573 buf->f_bsize = sb->s_blocksize; 574 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved; 575 buf->f_bfree = free; 576 buf->f_bavail = free; 577 buf->f_fsid.val[0] = (u32)id; 578 buf->f_fsid.val[1] = (u32)(id >> 32); 579 buf->f_namelen = 30; 580 return 0; 581 } 582 583 static struct dentry *affs_mount(struct file_system_type *fs_type, 584 int flags, const char *dev_name, void *data) 585 { 586 return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super); 587 } 588 589 static struct file_system_type affs_fs_type = { 590 .owner = THIS_MODULE, 591 .name = "affs", 592 .mount = affs_mount, 593 .kill_sb = kill_block_super, 594 .fs_flags = FS_REQUIRES_DEV, 595 }; 596 597 static int __init init_affs_fs(void) 598 { 599 int err = init_inodecache(); 600 if (err) 601 goto out1; 602 err = register_filesystem(&affs_fs_type); 603 if (err) 604 goto out; 605 return 0; 606 out: 607 destroy_inodecache(); 608 out1: 609 return err; 610 } 611 612 static void __exit exit_affs_fs(void) 613 { 614 unregister_filesystem(&affs_fs_type); 615 destroy_inodecache(); 616 } 617 618 MODULE_DESCRIPTION("Amiga filesystem support for Linux"); 619 MODULE_LICENSE("GPL"); 620 621 module_init(init_affs_fs) 622 module_exit(exit_affs_fs) 623