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 <linux/slab.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 clean) 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 tail->bm_flag = cpu_to_be32(clean); 36 secs_to_datestamp(get_seconds(), &tail->disk_change); 37 affs_fix_checksum(sb, bh); 38 mark_buffer_dirty(bh); 39 } 40 41 static void 42 affs_put_super(struct super_block *sb) 43 { 44 struct affs_sb_info *sbi = AFFS_SB(sb); 45 pr_debug("AFFS: put_super()\n"); 46 47 lock_kernel(); 48 49 if (!(sb->s_flags & MS_RDONLY)) 50 affs_commit_super(sb, 1); 51 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 unlock_kernel(); 59 } 60 61 static void 62 affs_write_super(struct super_block *sb) 63 { 64 int clean = 2; 65 66 lock_super(sb); 67 if (!(sb->s_flags & MS_RDONLY)) { 68 // if (sbi->s_bitmap[i].bm_bh) { 69 // if (buffer_dirty(sbi->s_bitmap[i].bm_bh)) { 70 // clean = 0; 71 affs_commit_super(sb, clean); 72 sb->s_dirt = !clean; /* redo until bitmap synced */ 73 } else 74 sb->s_dirt = 0; 75 unlock_super(sb); 76 77 pr_debug("AFFS: write_super() at %lu, clean=%d\n", get_seconds(), clean); 78 } 79 80 static int 81 affs_sync_fs(struct super_block *sb, int wait) 82 { 83 lock_super(sb); 84 affs_commit_super(sb, 2); 85 sb->s_dirt = 0; 86 unlock_super(sb); 87 return 0; 88 } 89 90 static struct kmem_cache * affs_inode_cachep; 91 92 static struct inode *affs_alloc_inode(struct super_block *sb) 93 { 94 struct affs_inode_info *i; 95 96 i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL); 97 if (!i) 98 return NULL; 99 100 i->vfs_inode.i_version = 1; 101 i->i_lc = NULL; 102 i->i_ext_bh = NULL; 103 i->i_pa_cnt = 0; 104 105 return &i->vfs_inode; 106 } 107 108 static void affs_destroy_inode(struct inode *inode) 109 { 110 kmem_cache_free(affs_inode_cachep, AFFS_I(inode)); 111 } 112 113 static void init_once(void *foo) 114 { 115 struct affs_inode_info *ei = (struct affs_inode_info *) foo; 116 117 init_MUTEX(&ei->i_link_lock); 118 init_MUTEX(&ei->i_ext_lock); 119 inode_init_once(&ei->vfs_inode); 120 } 121 122 static int init_inodecache(void) 123 { 124 affs_inode_cachep = kmem_cache_create("affs_inode_cache", 125 sizeof(struct affs_inode_info), 126 0, (SLAB_RECLAIM_ACCOUNT| 127 SLAB_MEM_SPREAD), 128 init_once); 129 if (affs_inode_cachep == NULL) 130 return -ENOMEM; 131 return 0; 132 } 133 134 static void destroy_inodecache(void) 135 { 136 kmem_cache_destroy(affs_inode_cachep); 137 } 138 139 static const struct super_operations affs_sops = { 140 .alloc_inode = affs_alloc_inode, 141 .destroy_inode = affs_destroy_inode, 142 .write_inode = affs_write_inode, 143 .delete_inode = affs_delete_inode, 144 .clear_inode = affs_clear_inode, 145 .put_super = affs_put_super, 146 .write_super = affs_write_super, 147 .sync_fs = affs_sync_fs, 148 .statfs = affs_statfs, 149 .remount_fs = affs_remount, 150 .show_options = generic_show_options, 151 }; 152 153 enum { 154 Opt_bs, Opt_mode, Opt_mufs, Opt_prefix, Opt_protect, 155 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid, 156 Opt_verbose, Opt_volume, Opt_ignore, Opt_err, 157 }; 158 159 static const match_table_t tokens = { 160 {Opt_bs, "bs=%u"}, 161 {Opt_mode, "mode=%o"}, 162 {Opt_mufs, "mufs"}, 163 {Opt_prefix, "prefix=%s"}, 164 {Opt_protect, "protect"}, 165 {Opt_reserved, "reserved=%u"}, 166 {Opt_root, "root=%u"}, 167 {Opt_setgid, "setgid=%u"}, 168 {Opt_setuid, "setuid=%u"}, 169 {Opt_verbose, "verbose"}, 170 {Opt_volume, "volume=%s"}, 171 {Opt_ignore, "grpquota"}, 172 {Opt_ignore, "noquota"}, 173 {Opt_ignore, "quota"}, 174 {Opt_ignore, "usrquota"}, 175 {Opt_err, NULL}, 176 }; 177 178 static int 179 parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root, 180 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts) 181 { 182 char *p; 183 substring_t args[MAX_OPT_ARGS]; 184 185 /* Fill in defaults */ 186 187 *uid = current_uid(); 188 *gid = current_gid(); 189 *reserved = 2; 190 *root = -1; 191 *blocksize = -1; 192 volume[0] = ':'; 193 volume[1] = 0; 194 *mount_opts = 0; 195 if (!options) 196 return 1; 197 198 while ((p = strsep(&options, ",")) != NULL) { 199 int token, n, option; 200 if (!*p) 201 continue; 202 203 token = match_token(p, tokens, args); 204 switch (token) { 205 case Opt_bs: 206 if (match_int(&args[0], &n)) 207 return 0; 208 if (n != 512 && n != 1024 && n != 2048 209 && n != 4096) { 210 printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n"); 211 return 0; 212 } 213 *blocksize = n; 214 break; 215 case Opt_mode: 216 if (match_octal(&args[0], &option)) 217 return 0; 218 *mode = option & 0777; 219 *mount_opts |= SF_SETMODE; 220 break; 221 case Opt_mufs: 222 *mount_opts |= SF_MUFS; 223 break; 224 case Opt_prefix: 225 *prefix = match_strdup(&args[0]); 226 if (!*prefix) 227 return 0; 228 *mount_opts |= SF_PREFIX; 229 break; 230 case Opt_protect: 231 *mount_opts |= SF_IMMUTABLE; 232 break; 233 case Opt_reserved: 234 if (match_int(&args[0], reserved)) 235 return 0; 236 break; 237 case Opt_root: 238 if (match_int(&args[0], root)) 239 return 0; 240 break; 241 case Opt_setgid: 242 if (match_int(&args[0], &option)) 243 return 0; 244 *gid = option; 245 *mount_opts |= SF_SETGID; 246 break; 247 case Opt_setuid: 248 if (match_int(&args[0], &option)) 249 return 0; 250 *uid = option; 251 *mount_opts |= SF_SETUID; 252 break; 253 case Opt_verbose: 254 *mount_opts |= SF_VERBOSE; 255 break; 256 case Opt_volume: { 257 char *vol = match_strdup(&args[0]); 258 if (!vol) 259 return 0; 260 strlcpy(volume, vol, 32); 261 kfree(vol); 262 break; 263 } 264 case Opt_ignore: 265 /* Silently ignore the quota options */ 266 break; 267 default: 268 printk("AFFS: Unrecognized mount option \"%s\" " 269 "or missing value\n", p); 270 return 0; 271 } 272 } 273 return 1; 274 } 275 276 /* This function definitely needs to be split up. Some fine day I'll 277 * hopefully have the guts to do so. Until then: sorry for the mess. 278 */ 279 280 static int affs_fill_super(struct super_block *sb, void *data, int silent) 281 { 282 struct affs_sb_info *sbi; 283 struct buffer_head *root_bh = NULL; 284 struct buffer_head *boot_bh; 285 struct inode *root_inode = NULL; 286 s32 root_block; 287 int size, blocksize; 288 u32 chksum; 289 int num_bm; 290 int i, j; 291 s32 key; 292 uid_t uid; 293 gid_t gid; 294 int reserved; 295 unsigned long mount_flags; 296 int tmp_flags; /* fix remount prototype... */ 297 u8 sig[4]; 298 int ret = -EINVAL; 299 300 save_mount_options(sb, data); 301 302 pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options"); 303 304 sb->s_magic = AFFS_SUPER_MAGIC; 305 sb->s_op = &affs_sops; 306 sb->s_flags |= MS_NODIRATIME; 307 308 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL); 309 if (!sbi) 310 return -ENOMEM; 311 sb->s_fs_info = sbi; 312 mutex_init(&sbi->s_bmlock); 313 spin_lock_init(&sbi->symlink_lock); 314 315 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block, 316 &blocksize,&sbi->s_prefix, 317 sbi->s_volume, &mount_flags)) { 318 printk(KERN_ERR "AFFS: Error parsing options\n"); 319 kfree(sbi->s_prefix); 320 kfree(sbi); 321 return -EINVAL; 322 } 323 /* N.B. after this point s_prefix must be released */ 324 325 sbi->s_flags = mount_flags; 326 sbi->s_mode = i; 327 sbi->s_uid = uid; 328 sbi->s_gid = gid; 329 sbi->s_reserved= reserved; 330 331 /* Get the size of the device in 512-byte blocks. 332 * If we later see that the partition uses bigger 333 * blocks, we will have to change it. 334 */ 335 336 size = sb->s_bdev->bd_inode->i_size >> 9; 337 pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size); 338 339 affs_set_blocksize(sb, PAGE_SIZE); 340 /* Try to find root block. Its location depends on the block size. */ 341 342 i = 512; 343 j = 4096; 344 if (blocksize > 0) { 345 i = j = blocksize; 346 size = size / (blocksize / 512); 347 } 348 for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) { 349 sbi->s_root_block = root_block; 350 if (root_block < 0) 351 sbi->s_root_block = (reserved + size - 1) / 2; 352 pr_debug("AFFS: setting blocksize to %d\n", blocksize); 353 affs_set_blocksize(sb, blocksize); 354 sbi->s_partition_size = size; 355 356 /* The root block location that was calculated above is not 357 * correct if the partition size is an odd number of 512- 358 * byte blocks, which will be rounded down to a number of 359 * 1024-byte blocks, and if there were an even number of 360 * reserved blocks. Ideally, all partition checkers should 361 * report the real number of blocks of the real blocksize, 362 * but since this just cannot be done, we have to try to 363 * find the root block anyways. In the above case, it is one 364 * block behind the calculated one. So we check this one, too. 365 */ 366 for (num_bm = 0; num_bm < 2; num_bm++) { 367 pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, " 368 "size=%d, reserved=%d\n", 369 sb->s_id, 370 sbi->s_root_block + num_bm, 371 blocksize, size, reserved); 372 root_bh = affs_bread(sb, sbi->s_root_block + num_bm); 373 if (!root_bh) 374 continue; 375 if (!affs_checksum_block(sb, root_bh) && 376 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT && 377 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) { 378 sbi->s_hashsize = blocksize / 4 - 56; 379 sbi->s_root_block += num_bm; 380 key = 1; 381 goto got_root; 382 } 383 affs_brelse(root_bh); 384 root_bh = NULL; 385 } 386 } 387 if (!silent) 388 printk(KERN_ERR "AFFS: No valid root block on device %s\n", 389 sb->s_id); 390 goto out_error; 391 392 /* N.B. after this point bh must be released */ 393 got_root: 394 root_block = sbi->s_root_block; 395 396 /* Find out which kind of FS we have */ 397 boot_bh = sb_bread(sb, 0); 398 if (!boot_bh) { 399 printk(KERN_ERR "AFFS: Cannot read boot block\n"); 400 goto out_error; 401 } 402 memcpy(sig, boot_bh->b_data, 4); 403 brelse(boot_bh); 404 chksum = be32_to_cpu(*(__be32 *)sig); 405 406 /* Dircache filesystems are compatible with non-dircache ones 407 * when reading. As long as they aren't supported, writing is 408 * not recommended. 409 */ 410 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS 411 || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) { 412 printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n", 413 sb->s_id); 414 sb->s_flags |= MS_RDONLY; 415 } 416 switch (chksum) { 417 case MUFS_FS: 418 case MUFS_INTLFFS: 419 case MUFS_DCFFS: 420 sbi->s_flags |= SF_MUFS; 421 /* fall thru */ 422 case FS_INTLFFS: 423 case FS_DCFFS: 424 sbi->s_flags |= SF_INTL; 425 break; 426 case MUFS_FFS: 427 sbi->s_flags |= SF_MUFS; 428 break; 429 case FS_FFS: 430 break; 431 case MUFS_OFS: 432 sbi->s_flags |= SF_MUFS; 433 /* fall thru */ 434 case FS_OFS: 435 sbi->s_flags |= SF_OFS; 436 sb->s_flags |= MS_NOEXEC; 437 break; 438 case MUFS_DCOFS: 439 case MUFS_INTLOFS: 440 sbi->s_flags |= SF_MUFS; 441 case FS_DCOFS: 442 case FS_INTLOFS: 443 sbi->s_flags |= SF_INTL | SF_OFS; 444 sb->s_flags |= MS_NOEXEC; 445 break; 446 default: 447 printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n", 448 sb->s_id, chksum); 449 goto out_error; 450 } 451 452 if (mount_flags & SF_VERBOSE) { 453 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0]; 454 printk(KERN_NOTICE "AFFS: Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n", 455 len > 31 ? 31 : len, 456 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1, 457 sig, sig[3] + '0', blocksize); 458 } 459 460 sb->s_flags |= MS_NODEV | MS_NOSUID; 461 462 sbi->s_data_blksize = sb->s_blocksize; 463 if (sbi->s_flags & SF_OFS) 464 sbi->s_data_blksize -= 24; 465 466 /* Keep super block in cache */ 467 sbi->s_root_bh = root_bh; 468 /* N.B. after this point s_root_bh must be released */ 469 470 tmp_flags = sb->s_flags; 471 if (affs_init_bitmap(sb, &tmp_flags)) 472 goto out_error; 473 sb->s_flags = tmp_flags; 474 475 /* set up enough so that it can read an inode */ 476 477 root_inode = affs_iget(sb, root_block); 478 if (IS_ERR(root_inode)) { 479 ret = PTR_ERR(root_inode); 480 goto out_error_noinode; 481 } 482 483 sb->s_root = d_alloc_root(root_inode); 484 if (!sb->s_root) { 485 printk(KERN_ERR "AFFS: Get root inode failed\n"); 486 goto out_error; 487 } 488 sb->s_root->d_op = &affs_dentry_operations; 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 if (root_inode) 498 iput(root_inode); 499 out_error_noinode: 500 kfree(sbi->s_bitmap); 501 affs_brelse(root_bh); 502 kfree(sbi->s_prefix); 503 kfree(sbi); 504 sb->s_fs_info = NULL; 505 return ret; 506 } 507 508 static int 509 affs_remount(struct super_block *sb, int *flags, char *data) 510 { 511 struct affs_sb_info *sbi = AFFS_SB(sb); 512 int blocksize; 513 uid_t uid; 514 gid_t gid; 515 int mode; 516 int reserved; 517 int root_block; 518 unsigned long mount_flags; 519 int res = 0; 520 char *new_opts = kstrdup(data, GFP_KERNEL); 521 char volume[32]; 522 char *prefix = NULL; 523 524 pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data); 525 526 *flags |= MS_NODIRATIME; 527 528 memcpy(volume, sbi->s_volume, 32); 529 if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block, 530 &blocksize, &prefix, volume, 531 &mount_flags)) { 532 kfree(prefix); 533 kfree(new_opts); 534 return -EINVAL; 535 } 536 lock_kernel(); 537 replace_mount_options(sb, new_opts); 538 539 sbi->s_flags = mount_flags; 540 sbi->s_mode = mode; 541 sbi->s_uid = uid; 542 sbi->s_gid = gid; 543 /* protect against readers */ 544 spin_lock(&sbi->symlink_lock); 545 if (prefix) { 546 kfree(sbi->s_prefix); 547 sbi->s_prefix = prefix; 548 } 549 memcpy(sbi->s_volume, volume, 32); 550 spin_unlock(&sbi->symlink_lock); 551 552 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) { 553 unlock_kernel(); 554 return 0; 555 } 556 if (*flags & MS_RDONLY) { 557 sb->s_dirt = 1; 558 while (sb->s_dirt) 559 affs_write_super(sb); 560 affs_free_bitmap(sb); 561 } else 562 res = affs_init_bitmap(sb, flags); 563 564 unlock_kernel(); 565 return res; 566 } 567 568 static int 569 affs_statfs(struct dentry *dentry, struct kstatfs *buf) 570 { 571 struct super_block *sb = dentry->d_sb; 572 int free; 573 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 574 575 pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size, 576 AFFS_SB(sb)->s_reserved); 577 578 free = affs_count_free_blocks(sb); 579 buf->f_type = AFFS_SUPER_MAGIC; 580 buf->f_bsize = sb->s_blocksize; 581 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved; 582 buf->f_bfree = free; 583 buf->f_bavail = free; 584 buf->f_fsid.val[0] = (u32)id; 585 buf->f_fsid.val[1] = (u32)(id >> 32); 586 buf->f_namelen = 30; 587 return 0; 588 } 589 590 static int affs_get_sb(struct file_system_type *fs_type, 591 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 592 { 593 return get_sb_bdev(fs_type, flags, dev_name, data, affs_fill_super, 594 mnt); 595 } 596 597 static struct file_system_type affs_fs_type = { 598 .owner = THIS_MODULE, 599 .name = "affs", 600 .get_sb = affs_get_sb, 601 .kill_sb = kill_block_super, 602 .fs_flags = FS_REQUIRES_DEV, 603 }; 604 605 static int __init init_affs_fs(void) 606 { 607 int err = init_inodecache(); 608 if (err) 609 goto out1; 610 err = register_filesystem(&affs_fs_type); 611 if (err) 612 goto out; 613 return 0; 614 out: 615 destroy_inodecache(); 616 out1: 617 return err; 618 } 619 620 static void __exit exit_affs_fs(void) 621 { 622 unregister_filesystem(&affs_fs_type); 623 destroy_inodecache(); 624 } 625 626 MODULE_DESCRIPTION("Amiga filesystem support for Linux"); 627 MODULE_LICENSE("GPL"); 628 629 module_init(init_affs_fs) 630 module_exit(exit_affs_fs) 631