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