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