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 "affs.h" 19 20 extern struct timezone sys_tz; 21 22 static int affs_statfs(struct dentry *dentry, struct kstatfs *buf); 23 static int affs_remount (struct super_block *sb, int *flags, char *data); 24 25 static void 26 affs_put_super(struct super_block *sb) 27 { 28 struct affs_sb_info *sbi = AFFS_SB(sb); 29 pr_debug("AFFS: put_super()\n"); 30 31 if (!(sb->s_flags & MS_RDONLY)) { 32 AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->bm_flag = cpu_to_be32(1); 33 secs_to_datestamp(get_seconds(), 34 &AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->disk_change); 35 affs_fix_checksum(sb, sbi->s_root_bh); 36 mark_buffer_dirty(sbi->s_root_bh); 37 } 38 39 kfree(sbi->s_prefix); 40 affs_free_bitmap(sb); 41 affs_brelse(sbi->s_root_bh); 42 kfree(sbi); 43 sb->s_fs_info = NULL; 44 return; 45 } 46 47 static void 48 affs_write_super(struct super_block *sb) 49 { 50 int clean = 2; 51 struct affs_sb_info *sbi = AFFS_SB(sb); 52 53 if (!(sb->s_flags & MS_RDONLY)) { 54 // if (sbi->s_bitmap[i].bm_bh) { 55 // if (buffer_dirty(sbi->s_bitmap[i].bm_bh)) { 56 // clean = 0; 57 AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->bm_flag = cpu_to_be32(clean); 58 secs_to_datestamp(get_seconds(), 59 &AFFS_ROOT_TAIL(sb, sbi->s_root_bh)->disk_change); 60 affs_fix_checksum(sb, sbi->s_root_bh); 61 mark_buffer_dirty(sbi->s_root_bh); 62 sb->s_dirt = !clean; /* redo until bitmap synced */ 63 } else 64 sb->s_dirt = 0; 65 66 pr_debug("AFFS: write_super() at %lu, clean=%d\n", get_seconds(), clean); 67 } 68 69 static struct kmem_cache * affs_inode_cachep; 70 71 static struct inode *affs_alloc_inode(struct super_block *sb) 72 { 73 struct affs_inode_info *ei; 74 ei = (struct affs_inode_info *)kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL); 75 if (!ei) 76 return NULL; 77 ei->vfs_inode.i_version = 1; 78 return &ei->vfs_inode; 79 } 80 81 static void affs_destroy_inode(struct inode *inode) 82 { 83 kmem_cache_free(affs_inode_cachep, AFFS_I(inode)); 84 } 85 86 static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags) 87 { 88 struct affs_inode_info *ei = (struct affs_inode_info *) foo; 89 90 if (flags & SLAB_CTOR_CONSTRUCTOR) { 91 init_MUTEX(&ei->i_link_lock); 92 init_MUTEX(&ei->i_ext_lock); 93 inode_init_once(&ei->vfs_inode); 94 } 95 } 96 97 static int init_inodecache(void) 98 { 99 affs_inode_cachep = kmem_cache_create("affs_inode_cache", 100 sizeof(struct affs_inode_info), 101 0, (SLAB_RECLAIM_ACCOUNT| 102 SLAB_MEM_SPREAD), 103 init_once, NULL); 104 if (affs_inode_cachep == NULL) 105 return -ENOMEM; 106 return 0; 107 } 108 109 static void destroy_inodecache(void) 110 { 111 kmem_cache_destroy(affs_inode_cachep); 112 } 113 114 static const struct super_operations affs_sops = { 115 .alloc_inode = affs_alloc_inode, 116 .destroy_inode = affs_destroy_inode, 117 .read_inode = affs_read_inode, 118 .write_inode = affs_write_inode, 119 .put_inode = affs_put_inode, 120 .drop_inode = affs_drop_inode, 121 .delete_inode = affs_delete_inode, 122 .clear_inode = affs_clear_inode, 123 .put_super = affs_put_super, 124 .write_super = affs_write_super, 125 .statfs = affs_statfs, 126 .remount_fs = affs_remount, 127 }; 128 129 enum { 130 Opt_bs, Opt_mode, Opt_mufs, Opt_prefix, Opt_protect, 131 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid, 132 Opt_verbose, Opt_volume, Opt_ignore, Opt_err, 133 }; 134 135 static match_table_t tokens = { 136 {Opt_bs, "bs=%u"}, 137 {Opt_mode, "mode=%o"}, 138 {Opt_mufs, "mufs"}, 139 {Opt_prefix, "prefix=%s"}, 140 {Opt_protect, "protect"}, 141 {Opt_reserved, "reserved=%u"}, 142 {Opt_root, "root=%u"}, 143 {Opt_setgid, "setgid=%u"}, 144 {Opt_setuid, "setuid=%u"}, 145 {Opt_verbose, "verbose"}, 146 {Opt_volume, "volume=%s"}, 147 {Opt_ignore, "grpquota"}, 148 {Opt_ignore, "noquota"}, 149 {Opt_ignore, "quota"}, 150 {Opt_ignore, "usrquota"}, 151 {Opt_err, NULL}, 152 }; 153 154 static int 155 parse_options(char *options, uid_t *uid, gid_t *gid, int *mode, int *reserved, s32 *root, 156 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts) 157 { 158 char *p; 159 substring_t args[MAX_OPT_ARGS]; 160 161 /* Fill in defaults */ 162 163 *uid = current->uid; 164 *gid = current->gid; 165 *reserved = 2; 166 *root = -1; 167 *blocksize = -1; 168 volume[0] = ':'; 169 volume[1] = 0; 170 *mount_opts = 0; 171 if (!options) 172 return 1; 173 174 while ((p = strsep(&options, ",")) != NULL) { 175 int token, n, option; 176 if (!*p) 177 continue; 178 179 token = match_token(p, tokens, args); 180 switch (token) { 181 case Opt_bs: 182 if (match_int(&args[0], &n)) 183 return -EINVAL; 184 if (n != 512 && n != 1024 && n != 2048 185 && n != 4096) { 186 printk ("AFFS: Invalid blocksize (512, 1024, 2048, 4096 allowed)\n"); 187 return 0; 188 } 189 *blocksize = n; 190 break; 191 case Opt_mode: 192 if (match_octal(&args[0], &option)) 193 return 1; 194 *mode = option & 0777; 195 *mount_opts |= SF_SETMODE; 196 break; 197 case Opt_mufs: 198 *mount_opts |= SF_MUFS; 199 break; 200 case Opt_prefix: 201 /* Free any previous prefix */ 202 kfree(*prefix); 203 *prefix = NULL; 204 *prefix = match_strdup(&args[0]); 205 if (!*prefix) 206 return 0; 207 *mount_opts |= SF_PREFIX; 208 break; 209 case Opt_protect: 210 *mount_opts |= SF_IMMUTABLE; 211 break; 212 case Opt_reserved: 213 if (match_int(&args[0], reserved)) 214 return 1; 215 break; 216 case Opt_root: 217 if (match_int(&args[0], root)) 218 return 1; 219 break; 220 case Opt_setgid: 221 if (match_int(&args[0], &option)) 222 return 1; 223 *gid = option; 224 *mount_opts |= SF_SETGID; 225 break; 226 case Opt_setuid: 227 if (match_int(&args[0], &option)) 228 return -EINVAL; 229 *uid = option; 230 *mount_opts |= SF_SETUID; 231 break; 232 case Opt_verbose: 233 *mount_opts |= SF_VERBOSE; 234 break; 235 case Opt_volume: { 236 char *vol = match_strdup(&args[0]); 237 strlcpy(volume, vol, 32); 238 kfree(vol); 239 break; 240 } 241 case Opt_ignore: 242 /* Silently ignore the quota options */ 243 break; 244 default: 245 printk("AFFS: Unrecognized mount option \"%s\" " 246 "or missing value\n", p); 247 return 0; 248 } 249 } 250 return 1; 251 } 252 253 /* This function definitely needs to be split up. Some fine day I'll 254 * hopefully have the guts to do so. Until then: sorry for the mess. 255 */ 256 257 static int affs_fill_super(struct super_block *sb, void *data, int silent) 258 { 259 struct affs_sb_info *sbi; 260 struct buffer_head *root_bh = NULL; 261 struct buffer_head *boot_bh; 262 struct inode *root_inode = NULL; 263 s32 root_block; 264 int size, blocksize; 265 u32 chksum; 266 int num_bm; 267 int i, j; 268 s32 key; 269 uid_t uid; 270 gid_t gid; 271 int reserved; 272 unsigned long mount_flags; 273 int tmp_flags; /* fix remount prototype... */ 274 u8 sig[4]; 275 276 pr_debug("AFFS: read_super(%s)\n",data ? (const char *)data : "no options"); 277 278 sb->s_magic = AFFS_SUPER_MAGIC; 279 sb->s_op = &affs_sops; 280 sb->s_flags |= MS_NODIRATIME; 281 282 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL); 283 if (!sbi) 284 return -ENOMEM; 285 sb->s_fs_info = sbi; 286 init_MUTEX(&sbi->s_bmlock); 287 288 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block, 289 &blocksize,&sbi->s_prefix, 290 sbi->s_volume, &mount_flags)) { 291 printk(KERN_ERR "AFFS: Error parsing options\n"); 292 return -EINVAL; 293 } 294 /* N.B. after this point s_prefix must be released */ 295 296 sbi->s_flags = mount_flags; 297 sbi->s_mode = i; 298 sbi->s_uid = uid; 299 sbi->s_gid = gid; 300 sbi->s_reserved= reserved; 301 302 /* Get the size of the device in 512-byte blocks. 303 * If we later see that the partition uses bigger 304 * blocks, we will have to change it. 305 */ 306 307 size = sb->s_bdev->bd_inode->i_size >> 9; 308 pr_debug("AFFS: initial blocksize=%d, #blocks=%d\n", 512, size); 309 310 affs_set_blocksize(sb, PAGE_SIZE); 311 /* Try to find root block. Its location depends on the block size. */ 312 313 i = 512; 314 j = 4096; 315 if (blocksize > 0) { 316 i = j = blocksize; 317 size = size / (blocksize / 512); 318 } 319 for (blocksize = i, key = 0; blocksize <= j; blocksize <<= 1, size >>= 1) { 320 sbi->s_root_block = root_block; 321 if (root_block < 0) 322 sbi->s_root_block = (reserved + size - 1) / 2; 323 pr_debug("AFFS: setting blocksize to %d\n", blocksize); 324 affs_set_blocksize(sb, blocksize); 325 sbi->s_partition_size = size; 326 327 /* The root block location that was calculated above is not 328 * correct if the partition size is an odd number of 512- 329 * byte blocks, which will be rounded down to a number of 330 * 1024-byte blocks, and if there were an even number of 331 * reserved blocks. Ideally, all partition checkers should 332 * report the real number of blocks of the real blocksize, 333 * but since this just cannot be done, we have to try to 334 * find the root block anyways. In the above case, it is one 335 * block behind the calculated one. So we check this one, too. 336 */ 337 for (num_bm = 0; num_bm < 2; num_bm++) { 338 pr_debug("AFFS: Dev %s, trying root=%u, bs=%d, " 339 "size=%d, reserved=%d\n", 340 sb->s_id, 341 sbi->s_root_block + num_bm, 342 blocksize, size, reserved); 343 root_bh = affs_bread(sb, sbi->s_root_block + num_bm); 344 if (!root_bh) 345 continue; 346 if (!affs_checksum_block(sb, root_bh) && 347 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT && 348 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) { 349 sbi->s_hashsize = blocksize / 4 - 56; 350 sbi->s_root_block += num_bm; 351 key = 1; 352 goto got_root; 353 } 354 affs_brelse(root_bh); 355 root_bh = NULL; 356 } 357 } 358 if (!silent) 359 printk(KERN_ERR "AFFS: No valid root block on device %s\n", 360 sb->s_id); 361 goto out_error; 362 363 /* N.B. after this point bh must be released */ 364 got_root: 365 root_block = sbi->s_root_block; 366 367 /* Find out which kind of FS we have */ 368 boot_bh = sb_bread(sb, 0); 369 if (!boot_bh) { 370 printk(KERN_ERR "AFFS: Cannot read boot block\n"); 371 goto out_error; 372 } 373 memcpy(sig, boot_bh->b_data, 4); 374 brelse(boot_bh); 375 chksum = be32_to_cpu(*(__be32 *)sig); 376 377 /* Dircache filesystems are compatible with non-dircache ones 378 * when reading. As long as they aren't supported, writing is 379 * not recommended. 380 */ 381 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS 382 || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) { 383 printk(KERN_NOTICE "AFFS: Dircache FS - mounting %s read only\n", 384 sb->s_id); 385 sb->s_flags |= MS_RDONLY; 386 } 387 switch (chksum) { 388 case MUFS_FS: 389 case MUFS_INTLFFS: 390 case MUFS_DCFFS: 391 sbi->s_flags |= SF_MUFS; 392 /* fall thru */ 393 case FS_INTLFFS: 394 case FS_DCFFS: 395 sbi->s_flags |= SF_INTL; 396 break; 397 case MUFS_FFS: 398 sbi->s_flags |= SF_MUFS; 399 break; 400 case FS_FFS: 401 break; 402 case MUFS_OFS: 403 sbi->s_flags |= SF_MUFS; 404 /* fall thru */ 405 case FS_OFS: 406 sbi->s_flags |= SF_OFS; 407 sb->s_flags |= MS_NOEXEC; 408 break; 409 case MUFS_DCOFS: 410 case MUFS_INTLOFS: 411 sbi->s_flags |= SF_MUFS; 412 case FS_DCOFS: 413 case FS_INTLOFS: 414 sbi->s_flags |= SF_INTL | SF_OFS; 415 sb->s_flags |= MS_NOEXEC; 416 break; 417 default: 418 printk(KERN_ERR "AFFS: Unknown filesystem on device %s: %08X\n", 419 sb->s_id, chksum); 420 goto out_error; 421 } 422 423 if (mount_flags & SF_VERBOSE) { 424 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0]; 425 printk(KERN_NOTICE "AFFS: Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n", 426 len > 31 ? 31 : len, 427 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1, 428 sig, sig[3] + '0', blocksize); 429 } 430 431 sb->s_flags |= MS_NODEV | MS_NOSUID; 432 433 sbi->s_data_blksize = sb->s_blocksize; 434 if (sbi->s_flags & SF_OFS) 435 sbi->s_data_blksize -= 24; 436 437 /* Keep super block in cache */ 438 sbi->s_root_bh = root_bh; 439 /* N.B. after this point s_root_bh must be released */ 440 441 tmp_flags = sb->s_flags; 442 if (affs_init_bitmap(sb, &tmp_flags)) 443 goto out_error; 444 sb->s_flags = tmp_flags; 445 446 /* set up enough so that it can read an inode */ 447 448 root_inode = iget(sb, root_block); 449 sb->s_root = d_alloc_root(root_inode); 450 if (!sb->s_root) { 451 printk(KERN_ERR "AFFS: Get root inode failed\n"); 452 goto out_error; 453 } 454 sb->s_root->d_op = &affs_dentry_operations; 455 456 pr_debug("AFFS: s_flags=%lX\n",sb->s_flags); 457 return 0; 458 459 /* 460 * Begin the cascaded cleanup ... 461 */ 462 out_error: 463 if (root_inode) 464 iput(root_inode); 465 kfree(sbi->s_bitmap); 466 affs_brelse(root_bh); 467 kfree(sbi->s_prefix); 468 kfree(sbi); 469 sb->s_fs_info = NULL; 470 return -EINVAL; 471 } 472 473 static int 474 affs_remount(struct super_block *sb, int *flags, char *data) 475 { 476 struct affs_sb_info *sbi = AFFS_SB(sb); 477 int blocksize; 478 uid_t uid; 479 gid_t gid; 480 int mode; 481 int reserved; 482 int root_block; 483 unsigned long mount_flags; 484 int res = 0; 485 486 pr_debug("AFFS: remount(flags=0x%x,opts=\"%s\")\n",*flags,data); 487 488 *flags |= MS_NODIRATIME; 489 490 if (!parse_options(data,&uid,&gid,&mode,&reserved,&root_block, 491 &blocksize,&sbi->s_prefix,sbi->s_volume,&mount_flags)) 492 return -EINVAL; 493 sbi->s_flags = mount_flags; 494 sbi->s_mode = mode; 495 sbi->s_uid = uid; 496 sbi->s_gid = gid; 497 498 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) 499 return 0; 500 if (*flags & MS_RDONLY) { 501 sb->s_dirt = 1; 502 while (sb->s_dirt) 503 affs_write_super(sb); 504 affs_free_bitmap(sb); 505 } else 506 res = affs_init_bitmap(sb, flags); 507 508 return res; 509 } 510 511 static int 512 affs_statfs(struct dentry *dentry, struct kstatfs *buf) 513 { 514 struct super_block *sb = dentry->d_sb; 515 int free; 516 517 pr_debug("AFFS: statfs() partsize=%d, reserved=%d\n",AFFS_SB(sb)->s_partition_size, 518 AFFS_SB(sb)->s_reserved); 519 520 free = affs_count_free_blocks(sb); 521 buf->f_type = AFFS_SUPER_MAGIC; 522 buf->f_bsize = sb->s_blocksize; 523 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved; 524 buf->f_bfree = free; 525 buf->f_bavail = free; 526 return 0; 527 } 528 529 static int affs_get_sb(struct file_system_type *fs_type, 530 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 531 { 532 return get_sb_bdev(fs_type, flags, dev_name, data, affs_fill_super, 533 mnt); 534 } 535 536 static struct file_system_type affs_fs_type = { 537 .owner = THIS_MODULE, 538 .name = "affs", 539 .get_sb = affs_get_sb, 540 .kill_sb = kill_block_super, 541 .fs_flags = FS_REQUIRES_DEV, 542 }; 543 544 static int __init init_affs_fs(void) 545 { 546 int err = init_inodecache(); 547 if (err) 548 goto out1; 549 err = register_filesystem(&affs_fs_type); 550 if (err) 551 goto out; 552 return 0; 553 out: 554 destroy_inodecache(); 555 out1: 556 return err; 557 } 558 559 static void __exit exit_affs_fs(void) 560 { 561 unregister_filesystem(&affs_fs_type); 562 destroy_inodecache(); 563 } 564 565 MODULE_DESCRIPTION("Amiga filesystem support for Linux"); 566 MODULE_LICENSE("GPL"); 567 568 module_init(init_affs_fs) 569 module_exit(exit_affs_fs) 570