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/smp_lock.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 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 } 39 40 static void 41 affs_put_super(struct super_block *sb) 42 { 43 struct affs_sb_info *sbi = AFFS_SB(sb); 44 pr_debug("AFFS: put_super()\n"); 45 46 lock_kernel(); 47 48 if (!(sb->s_flags & MS_RDONLY)) 49 affs_commit_super(sb, 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 unlock_kernel(); 58 } 59 60 static void 61 affs_write_super(struct super_block *sb) 62 { 63 int clean = 2; 64 65 lock_super(sb); 66 if (!(sb->s_flags & MS_RDONLY)) { 67 // if (sbi->s_bitmap[i].bm_bh) { 68 // if (buffer_dirty(sbi->s_bitmap[i].bm_bh)) { 69 // clean = 0; 70 affs_commit_super(sb, clean); 71 sb->s_dirt = !clean; /* redo until bitmap synced */ 72 } else 73 sb->s_dirt = 0; 74 unlock_super(sb); 75 76 pr_debug("AFFS: write_super() at %lu, clean=%d\n", get_seconds(), clean); 77 } 78 79 static int 80 affs_sync_fs(struct super_block *sb, int wait) 81 { 82 lock_super(sb); 83 affs_commit_super(sb, 2); 84 sb->s_dirt = 0; 85 unlock_super(sb); 86 return 0; 87 } 88 89 static struct kmem_cache * affs_inode_cachep; 90 91 static struct inode *affs_alloc_inode(struct super_block *sb) 92 { 93 struct affs_inode_info *i; 94 95 i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL); 96 if (!i) 97 return NULL; 98 99 i->vfs_inode.i_version = 1; 100 i->i_lc = NULL; 101 i->i_ext_bh = NULL; 102 i->i_pa_cnt = 0; 103 104 return &i->vfs_inode; 105 } 106 107 static void affs_destroy_inode(struct inode *inode) 108 { 109 kmem_cache_free(affs_inode_cachep, AFFS_I(inode)); 110 } 111 112 static void init_once(void *foo) 113 { 114 struct affs_inode_info *ei = (struct affs_inode_info *) foo; 115 116 init_MUTEX(&ei->i_link_lock); 117 init_MUTEX(&ei->i_ext_lock); 118 inode_init_once(&ei->vfs_inode); 119 } 120 121 static int init_inodecache(void) 122 { 123 affs_inode_cachep = kmem_cache_create("affs_inode_cache", 124 sizeof(struct affs_inode_info), 125 0, (SLAB_RECLAIM_ACCOUNT| 126 SLAB_MEM_SPREAD), 127 init_once); 128 if (affs_inode_cachep == NULL) 129 return -ENOMEM; 130 return 0; 131 } 132 133 static void destroy_inodecache(void) 134 { 135 kmem_cache_destroy(affs_inode_cachep); 136 } 137 138 static const struct super_operations affs_sops = { 139 .alloc_inode = affs_alloc_inode, 140 .destroy_inode = affs_destroy_inode, 141 .write_inode = affs_write_inode, 142 .delete_inode = affs_delete_inode, 143 .clear_inode = affs_clear_inode, 144 .put_super = affs_put_super, 145 .write_super = affs_write_super, 146 .sync_fs = affs_sync_fs, 147 .statfs = affs_statfs, 148 .remount_fs = affs_remount, 149 .show_options = generic_show_options, 150 }; 151 152 enum { 153 Opt_bs, Opt_mode, Opt_mufs, Opt_prefix, Opt_protect, 154 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid, 155 Opt_verbose, Opt_volume, Opt_ignore, Opt_err, 156 }; 157 158 static const match_table_t tokens = { 159 {Opt_bs, "bs=%u"}, 160 {Opt_mode, "mode=%o"}, 161 {Opt_mufs, "mufs"}, 162 {Opt_prefix, "prefix=%s"}, 163 {Opt_protect, "protect"}, 164 {Opt_reserved, "reserved=%u"}, 165 {Opt_root, "root=%u"}, 166 {Opt_setgid, "setgid=%u"}, 167 {Opt_setuid, "setuid=%u"}, 168 {Opt_verbose, "verbose"}, 169 {Opt_volume, "volume=%s"}, 170 {Opt_ignore, "grpquota"}, 171 {Opt_ignore, "noquota"}, 172 {Opt_ignore, "quota"}, 173 {Opt_ignore, "usrquota"}, 174 {Opt_err, NULL}, 175 }; 176 177 static int 178 parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root, 179 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts) 180 { 181 char *p; 182 substring_t args[MAX_OPT_ARGS]; 183 184 /* Fill in defaults */ 185 186 *uid = current_uid(); 187 *gid = current_gid(); 188 *reserved = 2; 189 *root = -1; 190 *blocksize = -1; 191 volume[0] = ':'; 192 volume[1] = 0; 193 *mount_opts = 0; 194 if (!options) 195 return 1; 196 197 while ((p = strsep(&options, ",")) != NULL) { 198 int token, n, option; 199 if (!*p) 200 continue; 201 202 token = match_token(p, tokens, args); 203 switch (token) { 204 case Opt_bs: 205 if (match_int(&args[0], &n)) 206 return 0; 207 if (n != 512 && n != 1024 && n != 2048 208 && n != 4096) { 209 printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n"); 210 return 0; 211 } 212 *blocksize = n; 213 break; 214 case Opt_mode: 215 if (match_octal(&args[0], &option)) 216 return 0; 217 *mode = option & 0777; 218 *mount_opts |= SF_SETMODE; 219 break; 220 case Opt_mufs: 221 *mount_opts |= SF_MUFS; 222 break; 223 case Opt_prefix: 224 *prefix = match_strdup(&args[0]); 225 if (!*prefix) 226 return 0; 227 *mount_opts |= SF_PREFIX; 228 break; 229 case Opt_protect: 230 *mount_opts |= SF_IMMUTABLE; 231 break; 232 case Opt_reserved: 233 if (match_int(&args[0], reserved)) 234 return 0; 235 break; 236 case Opt_root: 237 if (match_int(&args[0], root)) 238 return 0; 239 break; 240 case Opt_setgid: 241 if (match_int(&args[0], &option)) 242 return 0; 243 *gid = option; 244 *mount_opts |= SF_SETGID; 245 break; 246 case Opt_setuid: 247 if (match_int(&args[0], &option)) 248 return 0; 249 *uid = option; 250 *mount_opts |= SF_SETUID; 251 break; 252 case Opt_verbose: 253 *mount_opts |= SF_VERBOSE; 254 break; 255 case Opt_volume: { 256 char *vol = match_strdup(&args[0]); 257 if (!vol) 258 return 0; 259 strlcpy(volume, vol, 32); 260 kfree(vol); 261 break; 262 } 263 case Opt_ignore: 264 /* Silently ignore the quota options */ 265 break; 266 default: 267 printk("AFFS: Unrecognized mount option \"%s\" " 268 "or missing value\n", p); 269 return 0; 270 } 271 } 272 return 1; 273 } 274 275 /* This function definitely needs to be split up. Some fine day I'll 276 * hopefully have the guts to do so. Until then: sorry for the mess. 277 */ 278 279 static int affs_fill_super(struct super_block *sb, void *data, int silent) 280 { 281 struct affs_sb_info *sbi; 282 struct buffer_head *root_bh = NULL; 283 struct buffer_head *boot_bh; 284 struct inode *root_inode = NULL; 285 s32 root_block; 286 int size, blocksize; 287 u32 chksum; 288 int num_bm; 289 int i, j; 290 s32 key; 291 uid_t uid; 292 gid_t gid; 293 int reserved; 294 unsigned long mount_flags; 295 int tmp_flags; /* fix remount prototype... */ 296 u8 sig[4]; 297 int ret = -EINVAL; 298 299 save_mount_options(sb, data); 300 301 pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options"); 302 303 sb->s_magic = AFFS_SUPER_MAGIC; 304 sb->s_op = &affs_sops; 305 sb->s_flags |= MS_NODIRATIME; 306 307 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL); 308 if (!sbi) 309 return -ENOMEM; 310 sb->s_fs_info = sbi; 311 mutex_init(&sbi->s_bmlock); 312 spin_lock_init(&sbi->symlink_lock); 313 314 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block, 315 &blocksize,&sbi->s_prefix, 316 sbi->s_volume, &mount_flags)) { 317 printk(KERN_ERR "AFFS: Error parsing options\n"); 318 kfree(sbi->s_prefix); 319 kfree(sbi); 320 return -EINVAL; 321 } 322 /* N.B. after this point s_prefix must be released */ 323 324 sbi->s_flags = mount_flags; 325 sbi->s_mode = i; 326 sbi->s_uid = uid; 327 sbi->s_gid = gid; 328 sbi->s_reserved= reserved; 329 330 /* Get the size of the device in 512-byte blocks. 331 * If we later see that the partition uses bigger 332 * blocks, we will have to change it. 333 */ 334 335 size = sb->s_bdev->bd_inode->i_size >> 9; 336 pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size); 337 338 affs_set_blocksize(sb, PAGE_SIZE); 339 /* Try to find root block. Its location depends on the block size. */ 340 341 i = 512; 342 j = 4096; 343 if (blocksize > 0) { 344 i = j = blocksize; 345 size = size / (blocksize / 512); 346 } 347 for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) { 348 sbi->s_root_block = root_block; 349 if (root_block < 0) 350 sbi->s_root_block = (reserved + size - 1) / 2; 351 pr_debug("AFFS: setting blocksize to %d\n", blocksize); 352 affs_set_blocksize(sb, blocksize); 353 sbi->s_partition_size = size; 354 355 /* The root block location that was calculated above is not 356 * correct if the partition size is an odd number of 512- 357 * byte blocks, which will be rounded down to a number of 358 * 1024-byte blocks, and if there were an even number of 359 * reserved blocks. Ideally, all partition checkers should 360 * report the real number of blocks of the real blocksize, 361 * but since this just cannot be done, we have to try to 362 * find the root block anyways. In the above case, it is one 363 * block behind the calculated one. So we check this one, too. 364 */ 365 for (num_bm = 0; num_bm < 2; num_bm++) { 366 pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, " 367 "size=%d, reserved=%d\n", 368 sb->s_id, 369 sbi->s_root_block + num_bm, 370 blocksize, size, reserved); 371 root_bh = affs_bread(sb, sbi->s_root_block + num_bm); 372 if (!root_bh) 373 continue; 374 if (!affs_checksum_block(sb, root_bh) && 375 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT && 376 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) { 377 sbi->s_hashsize = blocksize / 4 - 56; 378 sbi->s_root_block += num_bm; 379 key = 1; 380 goto got_root; 381 } 382 affs_brelse(root_bh); 383 root_bh = NULL; 384 } 385 } 386 if (!silent) 387 printk(KERN_ERR "AFFS: No valid root block on device %s\n", 388 sb->s_id); 389 goto out_error; 390 391 /* N.B. after this point bh must be released */ 392 got_root: 393 root_block = sbi->s_root_block; 394 395 /* Find out which kind of FS we have */ 396 boot_bh = sb_bread(sb, 0); 397 if (!boot_bh) { 398 printk(KERN_ERR "AFFS: Cannot read boot block\n"); 399 goto out_error; 400 } 401 memcpy(sig, boot_bh->b_data, 4); 402 brelse(boot_bh); 403 chksum = be32_to_cpu(*(__be32 *)sig); 404 405 /* Dircache filesystems are compatible with non-dircache ones 406 * when reading. As long as they aren't supported, writing is 407 * not recommended. 408 */ 409 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS 410 || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) { 411 printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n", 412 sb->s_id); 413 sb->s_flags |= MS_RDONLY; 414 } 415 switch (chksum) { 416 case MUFS_FS: 417 case MUFS_INTLFFS: 418 case MUFS_DCFFS: 419 sbi->s_flags |= SF_MUFS; 420 /* fall thru */ 421 case FS_INTLFFS: 422 case FS_DCFFS: 423 sbi->s_flags |= SF_INTL; 424 break; 425 case MUFS_FFS: 426 sbi->s_flags |= SF_MUFS; 427 break; 428 case FS_FFS: 429 break; 430 case MUFS_OFS: 431 sbi->s_flags |= SF_MUFS; 432 /* fall thru */ 433 case FS_OFS: 434 sbi->s_flags |= SF_OFS; 435 sb->s_flags |= MS_NOEXEC; 436 break; 437 case MUFS_DCOFS: 438 case MUFS_INTLOFS: 439 sbi->s_flags |= SF_MUFS; 440 case FS_DCOFS: 441 case FS_INTLOFS: 442 sbi->s_flags |= SF_INTL | SF_OFS; 443 sb->s_flags |= MS_NOEXEC; 444 break; 445 default: 446 printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n", 447 sb->s_id, chksum); 448 goto out_error; 449 } 450 451 if (mount_flags & SF_VERBOSE) { 452 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0]; 453 printk(KERN_NOTICE "AFFS: Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n", 454 len > 31 ? 31 : len, 455 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1, 456 sig, sig[3] + '0', blocksize); 457 } 458 459 sb->s_flags |= MS_NODEV | MS_NOSUID; 460 461 sbi->s_data_blksize = sb->s_blocksize; 462 if (sbi->s_flags & SF_OFS) 463 sbi->s_data_blksize -= 24; 464 465 /* Keep super block in cache */ 466 sbi->s_root_bh = root_bh; 467 /* N.B. after this point s_root_bh must be released */ 468 469 tmp_flags = sb->s_flags; 470 if (affs_init_bitmap(sb, &tmp_flags)) 471 goto out_error; 472 sb->s_flags = tmp_flags; 473 474 /* set up enough so that it can read an inode */ 475 476 root_inode = affs_iget(sb, root_block); 477 if (IS_ERR(root_inode)) { 478 ret = PTR_ERR(root_inode); 479 goto out_error_noinode; 480 } 481 482 sb->s_root = d_alloc_root(root_inode); 483 if (!sb->s_root) { 484 printk(KERN_ERR "AFFS: Get root inode failed\n"); 485 goto out_error; 486 } 487 sb->s_root->d_op = &affs_dentry_operations; 488 489 pr_debug("AFFS: s_flags=%lX\n",sb->s_flags); 490 return 0; 491 492 /* 493 * Begin the cascaded cleanup ... 494 */ 495 out_error: 496 if (root_inode) 497 iput(root_inode); 498 out_error_noinode: 499 kfree(sbi->s_bitmap); 500 affs_brelse(root_bh); 501 kfree(sbi->s_prefix); 502 kfree(sbi); 503 sb->s_fs_info = NULL; 504 return ret; 505 } 506 507 static int 508 affs_remount(struct super_block *sb, int *flags, char *data) 509 { 510 struct affs_sb_info *sbi = AFFS_SB(sb); 511 int blocksize; 512 uid_t uid; 513 gid_t gid; 514 int mode; 515 int reserved; 516 int root_block; 517 unsigned long mount_flags; 518 int res = 0; 519 char *new_opts = kstrdup(data, GFP_KERNEL); 520 char volume[32]; 521 char *prefix = NULL; 522 523 pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data); 524 525 *flags |= MS_NODIRATIME; 526 527 memcpy(volume, sbi->s_volume, 32); 528 if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block, 529 &blocksize, &prefix, volume, 530 &mount_flags)) { 531 kfree(prefix); 532 kfree(new_opts); 533 return -EINVAL; 534 } 535 lock_kernel(); 536 replace_mount_options(sb, new_opts); 537 538 sbi->s_flags = mount_flags; 539 sbi->s_mode = mode; 540 sbi->s_uid = uid; 541 sbi->s_gid = gid; 542 /* protect against readers */ 543 spin_lock(&sbi->symlink_lock); 544 if (prefix) { 545 kfree(sbi->s_prefix); 546 sbi->s_prefix = prefix; 547 } 548 memcpy(sbi->s_volume, volume, 32); 549 spin_unlock(&sbi->symlink_lock); 550 551 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 552 unlock_kernel(); 553 return 0; 554 } 555 if (*flags & MS_RDONLY) { 556 sb->s_dirt = 1; 557 while (sb->s_dirt) 558 affs_write_super(sb); 559 affs_free_bitmap(sb); 560 } else 561 res = affs_init_bitmap(sb, flags); 562 563 unlock_kernel(); 564 return res; 565 } 566 567 static int 568 affs_statfs(struct dentry *dentry, struct kstatfs *buf) 569 { 570 struct super_block *sb = dentry->d_sb; 571 int free; 572 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 573 574 pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size, 575 AFFS_SB(sb)->s_reserved); 576 577 free = affs_count_free_blocks(sb); 578 buf->f_type = AFFS_SUPER_MAGIC; 579 buf->f_bsize = sb->s_blocksize; 580 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved; 581 buf->f_bfree = free; 582 buf->f_bavail = free; 583 buf->f_fsid.val[0] = (u32)id; 584 buf->f_fsid.val[1] = (u32)(id >> 32); 585 buf->f_namelen = 30; 586 return 0; 587 } 588 589 static int affs_get_sb(struct file_system_type *fs_type, 590 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 591 { 592 return get_sb_bdev(fs_type, flags, dev_name, data, affs_fill_super, 593 mnt); 594 } 595 596 static struct file_system_type affs_fs_type = { 597 .owner = THIS_MODULE, 598 .name = "affs", 599 .get_sb = affs_get_sb, 600 .kill_sb = kill_block_super, 601 .fs_flags = FS_REQUIRES_DEV, 602 }; 603 604 static int __init init_affs_fs(void) 605 { 606 int err = init_inodecache(); 607 if (err) 608 goto out1; 609 err = register_filesystem(&affs_fs_type); 610 if (err) 611 goto out; 612 return 0; 613 out: 614 destroy_inodecache(); 615 out1: 616 return err; 617 } 618 619 static void __exit exit_affs_fs(void) 620 { 621 unregister_filesystem(&affs_fs_type); 622 destroy_inodecache(); 623 } 624 625 MODULE_DESCRIPTION("Amiga filesystem support for Linux"); 626 MODULE_LICENSE("GPL"); 627 628 module_init(init_affs_fs) 629 module_exit(exit_affs_fs) 630