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