1 /* 2 * linux/fs/befs/linuxvfs.c 3 * 4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com 5 * 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10 #include <linux/module.h> 11 #include <linux/slab.h> 12 #include <linux/fs.h> 13 #include <linux/errno.h> 14 #include <linux/stat.h> 15 #include <linux/nls.h> 16 #include <linux/buffer_head.h> 17 #include <linux/vfs.h> 18 #include <linux/parser.h> 19 #include <linux/namei.h> 20 #include <linux/sched.h> 21 22 #include "befs.h" 23 #include "btree.h" 24 #include "inode.h" 25 #include "datastream.h" 26 #include "super.h" 27 #include "io.h" 28 29 MODULE_DESCRIPTION("BeOS File System (BeFS) driver"); 30 MODULE_AUTHOR("Will Dyson"); 31 MODULE_LICENSE("GPL"); 32 33 /* The units the vfs expects inode->i_blocks to be in */ 34 #define VFS_BLOCK_SIZE 512 35 36 static int befs_readdir(struct file *, struct dir_context *); 37 static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int); 38 static int befs_readpage(struct file *file, struct page *page); 39 static sector_t befs_bmap(struct address_space *mapping, sector_t block); 40 static struct dentry *befs_lookup(struct inode *, struct dentry *, unsigned int); 41 static struct inode *befs_iget(struct super_block *, unsigned long); 42 static struct inode *befs_alloc_inode(struct super_block *sb); 43 static void befs_destroy_inode(struct inode *inode); 44 static void befs_destroy_inodecache(void); 45 static int befs_symlink_readpage(struct file *, struct page *); 46 static int befs_utf2nls(struct super_block *sb, const char *in, int in_len, 47 char **out, int *out_len); 48 static int befs_nls2utf(struct super_block *sb, const char *in, int in_len, 49 char **out, int *out_len); 50 static void befs_put_super(struct super_block *); 51 static int befs_remount(struct super_block *, int *, char *); 52 static int befs_statfs(struct dentry *, struct kstatfs *); 53 static int parse_options(char *, struct befs_mount_options *); 54 55 static const struct super_operations befs_sops = { 56 .alloc_inode = befs_alloc_inode, /* allocate a new inode */ 57 .destroy_inode = befs_destroy_inode, /* deallocate an inode */ 58 .put_super = befs_put_super, /* uninit super */ 59 .statfs = befs_statfs, /* statfs */ 60 .remount_fs = befs_remount, 61 .show_options = generic_show_options, 62 }; 63 64 /* slab cache for befs_inode_info objects */ 65 static struct kmem_cache *befs_inode_cachep; 66 67 static const struct file_operations befs_dir_operations = { 68 .read = generic_read_dir, 69 .iterate_shared = befs_readdir, 70 .llseek = generic_file_llseek, 71 }; 72 73 static const struct inode_operations befs_dir_inode_operations = { 74 .lookup = befs_lookup, 75 }; 76 77 static const struct address_space_operations befs_aops = { 78 .readpage = befs_readpage, 79 .bmap = befs_bmap, 80 }; 81 82 static const struct address_space_operations befs_symlink_aops = { 83 .readpage = befs_symlink_readpage, 84 }; 85 86 /* 87 * Called by generic_file_read() to read a page of data 88 * 89 * In turn, simply calls a generic block read function and 90 * passes it the address of befs_get_block, for mapping file 91 * positions to disk blocks. 92 */ 93 static int 94 befs_readpage(struct file *file, struct page *page) 95 { 96 return block_read_full_page(page, befs_get_block); 97 } 98 99 static sector_t 100 befs_bmap(struct address_space *mapping, sector_t block) 101 { 102 return generic_block_bmap(mapping, block, befs_get_block); 103 } 104 105 /* 106 * Generic function to map a file position (block) to a 107 * disk offset (passed back in bh_result). 108 * 109 * Used by many higher level functions. 110 * 111 * Calls befs_fblock2brun() in datastream.c to do the real work. 112 * 113 * -WD 10-26-01 114 */ 115 116 static int 117 befs_get_block(struct inode *inode, sector_t block, 118 struct buffer_head *bh_result, int create) 119 { 120 struct super_block *sb = inode->i_sb; 121 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; 122 befs_block_run run = BAD_IADDR; 123 int res; 124 ulong disk_off; 125 126 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld", 127 (unsigned long)inode->i_ino, (long)block); 128 if (create) { 129 befs_error(sb, "befs_get_block() was asked to write to " 130 "block %ld in inode %lu", (long)block, 131 (unsigned long)inode->i_ino); 132 return -EPERM; 133 } 134 135 res = befs_fblock2brun(sb, ds, block, &run); 136 if (res != BEFS_OK) { 137 befs_error(sb, 138 "<--- %s for inode %lu, block %ld ERROR", 139 __func__, (unsigned long)inode->i_ino, 140 (long)block); 141 return -EFBIG; 142 } 143 144 disk_off = (ulong) iaddr2blockno(sb, &run); 145 146 map_bh(bh_result, inode->i_sb, disk_off); 147 148 befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu", 149 __func__, (unsigned long)inode->i_ino, (long)block, 150 (unsigned long)disk_off); 151 152 return 0; 153 } 154 155 static struct dentry * 156 befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 157 { 158 struct inode *inode; 159 struct super_block *sb = dir->i_sb; 160 const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds; 161 befs_off_t offset; 162 int ret; 163 int utfnamelen; 164 char *utfname; 165 const char *name = dentry->d_name.name; 166 167 befs_debug(sb, "---> %s name %pd inode %ld", __func__, 168 dentry, dir->i_ino); 169 170 /* Convert to UTF-8 */ 171 if (BEFS_SB(sb)->nls) { 172 ret = 173 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen); 174 if (ret < 0) { 175 befs_debug(sb, "<--- %s ERROR", __func__); 176 return ERR_PTR(ret); 177 } 178 ret = befs_btree_find(sb, ds, utfname, &offset); 179 kfree(utfname); 180 181 } else { 182 ret = befs_btree_find(sb, ds, name, &offset); 183 } 184 185 if (ret == BEFS_BT_NOT_FOUND) { 186 befs_debug(sb, "<--- %s %pd not found", __func__, dentry); 187 d_add(dentry, NULL); 188 return ERR_PTR(-ENOENT); 189 190 } else if (ret != BEFS_OK || offset == 0) { 191 befs_error(sb, "<--- %s Error", __func__); 192 return ERR_PTR(-ENODATA); 193 } 194 195 inode = befs_iget(dir->i_sb, (ino_t) offset); 196 if (IS_ERR(inode)) 197 return ERR_CAST(inode); 198 199 d_add(dentry, inode); 200 201 befs_debug(sb, "<--- %s", __func__); 202 203 return NULL; 204 } 205 206 static int 207 befs_readdir(struct file *file, struct dir_context *ctx) 208 { 209 struct inode *inode = file_inode(file); 210 struct super_block *sb = inode->i_sb; 211 const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; 212 befs_off_t value; 213 int result; 214 size_t keysize; 215 char keybuf[BEFS_NAME_LEN + 1]; 216 217 befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld", 218 __func__, file, inode->i_ino, ctx->pos); 219 220 while (1) { 221 result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1, 222 keybuf, &keysize, &value); 223 224 if (result == BEFS_ERR) { 225 befs_debug(sb, "<--- %s ERROR", __func__); 226 befs_error(sb, "IO error reading %pD (inode %lu)", 227 file, inode->i_ino); 228 return -EIO; 229 230 } else if (result == BEFS_BT_END) { 231 befs_debug(sb, "<--- %s END", __func__); 232 return 0; 233 234 } else if (result == BEFS_BT_EMPTY) { 235 befs_debug(sb, "<--- %s Empty directory", __func__); 236 return 0; 237 } 238 239 /* Convert to NLS */ 240 if (BEFS_SB(sb)->nls) { 241 char *nlsname; 242 int nlsnamelen; 243 244 result = 245 befs_utf2nls(sb, keybuf, keysize, &nlsname, 246 &nlsnamelen); 247 if (result < 0) { 248 befs_debug(sb, "<--- %s ERROR", __func__); 249 return result; 250 } 251 if (!dir_emit(ctx, nlsname, nlsnamelen, 252 (ino_t) value, DT_UNKNOWN)) { 253 kfree(nlsname); 254 return 0; 255 } 256 kfree(nlsname); 257 } else { 258 if (!dir_emit(ctx, keybuf, keysize, 259 (ino_t) value, DT_UNKNOWN)) 260 return 0; 261 } 262 ctx->pos++; 263 } 264 } 265 266 static struct inode * 267 befs_alloc_inode(struct super_block *sb) 268 { 269 struct befs_inode_info *bi; 270 271 bi = kmem_cache_alloc(befs_inode_cachep, GFP_KERNEL); 272 if (!bi) 273 return NULL; 274 return &bi->vfs_inode; 275 } 276 277 static void befs_i_callback(struct rcu_head *head) 278 { 279 struct inode *inode = container_of(head, struct inode, i_rcu); 280 kmem_cache_free(befs_inode_cachep, BEFS_I(inode)); 281 } 282 283 static void befs_destroy_inode(struct inode *inode) 284 { 285 call_rcu(&inode->i_rcu, befs_i_callback); 286 } 287 288 static void init_once(void *foo) 289 { 290 struct befs_inode_info *bi = (struct befs_inode_info *) foo; 291 292 inode_init_once(&bi->vfs_inode); 293 } 294 295 static struct inode *befs_iget(struct super_block *sb, unsigned long ino) 296 { 297 struct buffer_head *bh; 298 befs_inode *raw_inode; 299 struct befs_sb_info *befs_sb = BEFS_SB(sb); 300 struct befs_inode_info *befs_ino; 301 struct inode *inode; 302 303 befs_debug(sb, "---> %s inode = %lu", __func__, ino); 304 305 inode = iget_locked(sb, ino); 306 if (!inode) 307 return ERR_PTR(-ENOMEM); 308 if (!(inode->i_state & I_NEW)) 309 return inode; 310 311 befs_ino = BEFS_I(inode); 312 313 /* convert from vfs's inode number to befs's inode number */ 314 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino); 315 316 befs_debug(sb, " real inode number [%u, %hu, %hu]", 317 befs_ino->i_inode_num.allocation_group, 318 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len); 319 320 bh = sb_bread(sb, inode->i_ino); 321 if (!bh) { 322 befs_error(sb, "unable to read inode block - " 323 "inode = %lu", inode->i_ino); 324 goto unacquire_none; 325 } 326 327 raw_inode = (befs_inode *) bh->b_data; 328 329 befs_dump_inode(sb, raw_inode); 330 331 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) { 332 befs_error(sb, "Bad inode: %lu", inode->i_ino); 333 goto unacquire_bh; 334 } 335 336 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode); 337 338 /* 339 * set uid and gid. But since current BeOS is single user OS, so 340 * you can change by "uid" or "gid" options. 341 */ 342 343 inode->i_uid = befs_sb->mount_opts.use_uid ? 344 befs_sb->mount_opts.uid : 345 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid)); 346 inode->i_gid = befs_sb->mount_opts.use_gid ? 347 befs_sb->mount_opts.gid : 348 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid)); 349 350 set_nlink(inode, 1); 351 352 /* 353 * BEFS's time is 64 bits, but current VFS is 32 bits... 354 * BEFS don't have access time. Nor inode change time. VFS 355 * doesn't have creation time. 356 * Also, the lower 16 bits of the last_modified_time and 357 * create_time are just a counter to help ensure uniqueness 358 * for indexing purposes. (PFD, page 54) 359 */ 360 361 inode->i_mtime.tv_sec = 362 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16; 363 inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */ 364 inode->i_ctime = inode->i_mtime; 365 inode->i_atime = inode->i_mtime; 366 367 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num); 368 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent); 369 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes); 370 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags); 371 372 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){ 373 inode->i_size = 0; 374 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE; 375 strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink, 376 BEFS_SYMLINK_LEN); 377 } else { 378 int num_blks; 379 380 befs_ino->i_data.ds = 381 fsds_to_cpu(sb, &raw_inode->data.datastream); 382 383 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds); 384 inode->i_blocks = 385 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE); 386 inode->i_size = befs_ino->i_data.ds.size; 387 } 388 389 inode->i_mapping->a_ops = &befs_aops; 390 391 if (S_ISREG(inode->i_mode)) { 392 inode->i_fop = &generic_ro_fops; 393 } else if (S_ISDIR(inode->i_mode)) { 394 inode->i_op = &befs_dir_inode_operations; 395 inode->i_fop = &befs_dir_operations; 396 } else if (S_ISLNK(inode->i_mode)) { 397 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) { 398 inode->i_op = &page_symlink_inode_operations; 399 inode_nohighmem(inode); 400 inode->i_mapping->a_ops = &befs_symlink_aops; 401 } else { 402 inode->i_link = befs_ino->i_data.symlink; 403 inode->i_op = &simple_symlink_inode_operations; 404 } 405 } else { 406 befs_error(sb, "Inode %lu is not a regular file, " 407 "directory or symlink. THAT IS WRONG! BeFS has no " 408 "on disk special files", inode->i_ino); 409 goto unacquire_bh; 410 } 411 412 brelse(bh); 413 befs_debug(sb, "<--- %s", __func__); 414 unlock_new_inode(inode); 415 return inode; 416 417 unacquire_bh: 418 brelse(bh); 419 420 unacquire_none: 421 iget_failed(inode); 422 befs_debug(sb, "<--- %s - Bad inode", __func__); 423 return ERR_PTR(-EIO); 424 } 425 426 /* Initialize the inode cache. Called at fs setup. 427 * 428 * Taken from NFS implementation by Al Viro. 429 */ 430 static int __init 431 befs_init_inodecache(void) 432 { 433 befs_inode_cachep = kmem_cache_create("befs_inode_cache", 434 sizeof (struct befs_inode_info), 435 0, (SLAB_RECLAIM_ACCOUNT| 436 SLAB_MEM_SPREAD|SLAB_ACCOUNT), 437 init_once); 438 if (befs_inode_cachep == NULL) 439 return -ENOMEM; 440 441 return 0; 442 } 443 444 /* Called at fs teardown. 445 * 446 * Taken from NFS implementation by Al Viro. 447 */ 448 static void 449 befs_destroy_inodecache(void) 450 { 451 /* 452 * Make sure all delayed rcu free inodes are flushed before we 453 * destroy cache. 454 */ 455 rcu_barrier(); 456 kmem_cache_destroy(befs_inode_cachep); 457 } 458 459 /* 460 * The inode of symbolic link is different to data stream. 461 * The data stream become link name. Unless the LONG_SYMLINK 462 * flag is set. 463 */ 464 static int befs_symlink_readpage(struct file *unused, struct page *page) 465 { 466 struct inode *inode = page->mapping->host; 467 struct super_block *sb = inode->i_sb; 468 struct befs_inode_info *befs_ino = BEFS_I(inode); 469 befs_data_stream *data = &befs_ino->i_data.ds; 470 befs_off_t len = data->size; 471 char *link = page_address(page); 472 473 if (len == 0 || len > PAGE_SIZE) { 474 befs_error(sb, "Long symlink with illegal length"); 475 goto fail; 476 } 477 befs_debug(sb, "Follow long symlink"); 478 479 if (befs_read_lsymlink(sb, data, link, len) != len) { 480 befs_error(sb, "Failed to read entire long symlink"); 481 goto fail; 482 } 483 link[len - 1] = '\0'; 484 SetPageUptodate(page); 485 unlock_page(page); 486 return 0; 487 fail: 488 SetPageError(page); 489 unlock_page(page); 490 return -EIO; 491 } 492 493 /* 494 * UTF-8 to NLS charset convert routine 495 * 496 * Uses uni2char() / char2uni() rather than the nls tables directly 497 */ 498 static int 499 befs_utf2nls(struct super_block *sb, const char *in, 500 int in_len, char **out, int *out_len) 501 { 502 struct nls_table *nls = BEFS_SB(sb)->nls; 503 int i, o; 504 unicode_t uni; 505 int unilen, utflen; 506 char *result; 507 /* The utf8->nls conversion won't make the final nls string bigger 508 * than the utf one, but if the string is pure ascii they'll have the 509 * same width and an extra char is needed to save the additional \0 510 */ 511 int maxlen = in_len + 1; 512 513 befs_debug(sb, "---> %s", __func__); 514 515 if (!nls) { 516 befs_error(sb, "%s called with no NLS table loaded", __func__); 517 return -EINVAL; 518 } 519 520 *out = result = kmalloc(maxlen, GFP_NOFS); 521 if (!*out) { 522 return -ENOMEM; 523 } 524 525 for (i = o = 0; i < in_len; i += utflen, o += unilen) { 526 527 /* convert from UTF-8 to Unicode */ 528 utflen = utf8_to_utf32(&in[i], in_len - i, &uni); 529 if (utflen < 0) 530 goto conv_err; 531 532 /* convert from Unicode to nls */ 533 if (uni > MAX_WCHAR_T) 534 goto conv_err; 535 unilen = nls->uni2char(uni, &result[o], in_len - o); 536 if (unilen < 0) 537 goto conv_err; 538 } 539 result[o] = '\0'; 540 *out_len = o; 541 542 befs_debug(sb, "<--- %s", __func__); 543 544 return o; 545 546 conv_err: 547 befs_error(sb, "Name using character set %s contains a character that " 548 "cannot be converted to unicode.", nls->charset); 549 befs_debug(sb, "<--- %s", __func__); 550 kfree(result); 551 return -EILSEQ; 552 } 553 554 /** 555 * befs_nls2utf - Convert NLS string to utf8 encodeing 556 * @sb: Superblock 557 * @in: Input string buffer in NLS format 558 * @in_len: Length of input string in bytes 559 * @out: The output string in UTF-8 format 560 * @out_len: Length of the output buffer 561 * 562 * Converts input string @in, which is in the format of the loaded NLS map, 563 * into a utf8 string. 564 * 565 * The destination string @out is allocated by this function and the caller is 566 * responsible for freeing it with kfree() 567 * 568 * On return, *@out_len is the length of @out in bytes. 569 * 570 * On success, the return value is the number of utf8 characters written to 571 * the output buffer @out. 572 * 573 * On Failure, a negative number coresponding to the error code is returned. 574 */ 575 576 static int 577 befs_nls2utf(struct super_block *sb, const char *in, 578 int in_len, char **out, int *out_len) 579 { 580 struct nls_table *nls = BEFS_SB(sb)->nls; 581 int i, o; 582 wchar_t uni; 583 int unilen, utflen; 584 char *result; 585 /* 586 * There are nls characters that will translate to 3-chars-wide UTF-8 587 * characters, an additional byte is needed to save the final \0 588 * in special cases */ 589 int maxlen = (3 * in_len) + 1; 590 591 befs_debug(sb, "---> %s\n", __func__); 592 593 if (!nls) { 594 befs_error(sb, "%s called with no NLS table loaded.", 595 __func__); 596 return -EINVAL; 597 } 598 599 *out = result = kmalloc(maxlen, GFP_NOFS); 600 if (!*out) { 601 *out_len = 0; 602 return -ENOMEM; 603 } 604 605 for (i = o = 0; i < in_len; i += unilen, o += utflen) { 606 607 /* convert from nls to unicode */ 608 unilen = nls->char2uni(&in[i], in_len - i, &uni); 609 if (unilen < 0) 610 goto conv_err; 611 612 /* convert from unicode to UTF-8 */ 613 utflen = utf32_to_utf8(uni, &result[o], 3); 614 if (utflen <= 0) 615 goto conv_err; 616 } 617 618 result[o] = '\0'; 619 *out_len = o; 620 621 befs_debug(sb, "<--- %s", __func__); 622 623 return i; 624 625 conv_err: 626 befs_error(sb, "Name using character set %s contains a character that " 627 "cannot be converted to unicode.", nls->charset); 628 befs_debug(sb, "<--- %s", __func__); 629 kfree(result); 630 return -EILSEQ; 631 } 632 633 enum { 634 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err, 635 }; 636 637 static const match_table_t befs_tokens = { 638 {Opt_uid, "uid=%d"}, 639 {Opt_gid, "gid=%d"}, 640 {Opt_charset, "iocharset=%s"}, 641 {Opt_debug, "debug"}, 642 {Opt_err, NULL} 643 }; 644 645 static int 646 parse_options(char *options, struct befs_mount_options *opts) 647 { 648 char *p; 649 substring_t args[MAX_OPT_ARGS]; 650 int option; 651 kuid_t uid; 652 kgid_t gid; 653 654 /* Initialize options */ 655 opts->uid = GLOBAL_ROOT_UID; 656 opts->gid = GLOBAL_ROOT_GID; 657 opts->use_uid = 0; 658 opts->use_gid = 0; 659 opts->iocharset = NULL; 660 opts->debug = 0; 661 662 if (!options) 663 return 1; 664 665 while ((p = strsep(&options, ",")) != NULL) { 666 int token; 667 if (!*p) 668 continue; 669 670 token = match_token(p, befs_tokens, args); 671 switch (token) { 672 case Opt_uid: 673 if (match_int(&args[0], &option)) 674 return 0; 675 uid = INVALID_UID; 676 if (option >= 0) 677 uid = make_kuid(current_user_ns(), option); 678 if (!uid_valid(uid)) { 679 pr_err("Invalid uid %d, " 680 "using default\n", option); 681 break; 682 } 683 opts->uid = uid; 684 opts->use_uid = 1; 685 break; 686 case Opt_gid: 687 if (match_int(&args[0], &option)) 688 return 0; 689 gid = INVALID_GID; 690 if (option >= 0) 691 gid = make_kgid(current_user_ns(), option); 692 if (!gid_valid(gid)) { 693 pr_err("Invalid gid %d, " 694 "using default\n", option); 695 break; 696 } 697 opts->gid = gid; 698 opts->use_gid = 1; 699 break; 700 case Opt_charset: 701 kfree(opts->iocharset); 702 opts->iocharset = match_strdup(&args[0]); 703 if (!opts->iocharset) { 704 pr_err("allocation failure for " 705 "iocharset string\n"); 706 return 0; 707 } 708 break; 709 case Opt_debug: 710 opts->debug = 1; 711 break; 712 default: 713 pr_err("Unrecognized mount option \"%s\" " 714 "or missing value\n", p); 715 return 0; 716 } 717 } 718 return 1; 719 } 720 721 /* This function has the responsibiltiy of getting the 722 * filesystem ready for unmounting. 723 * Basically, we free everything that we allocated in 724 * befs_read_inode 725 */ 726 static void 727 befs_put_super(struct super_block *sb) 728 { 729 kfree(BEFS_SB(sb)->mount_opts.iocharset); 730 BEFS_SB(sb)->mount_opts.iocharset = NULL; 731 unload_nls(BEFS_SB(sb)->nls); 732 kfree(sb->s_fs_info); 733 sb->s_fs_info = NULL; 734 } 735 736 /* Allocate private field of the superblock, fill it. 737 * 738 * Finish filling the public superblock fields 739 * Make the root directory 740 * Load a set of NLS translations if needed. 741 */ 742 static int 743 befs_fill_super(struct super_block *sb, void *data, int silent) 744 { 745 struct buffer_head *bh; 746 struct befs_sb_info *befs_sb; 747 befs_super_block *disk_sb; 748 struct inode *root; 749 long ret = -EINVAL; 750 const unsigned long sb_block = 0; 751 const off_t x86_sb_off = 512; 752 int blocksize; 753 754 save_mount_options(sb, data); 755 756 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL); 757 if (sb->s_fs_info == NULL) 758 goto unacquire_none; 759 760 befs_sb = BEFS_SB(sb); 761 762 if (!parse_options((char *) data, &befs_sb->mount_opts)) { 763 if (!silent) 764 befs_error(sb, "cannot parse mount options"); 765 goto unacquire_priv_sbp; 766 } 767 768 befs_debug(sb, "---> %s", __func__); 769 770 if (!(sb->s_flags & MS_RDONLY)) { 771 befs_warning(sb, 772 "No write support. Marking filesystem read-only"); 773 sb->s_flags |= MS_RDONLY; 774 } 775 776 /* 777 * Set dummy blocksize to read super block. 778 * Will be set to real fs blocksize later. 779 * 780 * Linux 2.4.10 and later refuse to read blocks smaller than 781 * the logical block size for the device. But we also need to read at 782 * least 1k to get the second 512 bytes of the volume. 783 * -WD 10-26-01 784 */ 785 blocksize = sb_min_blocksize(sb, 1024); 786 if (!blocksize) { 787 if (!silent) 788 befs_error(sb, "unable to set blocksize"); 789 goto unacquire_priv_sbp; 790 } 791 792 if (!(bh = sb_bread(sb, sb_block))) { 793 if (!silent) 794 befs_error(sb, "unable to read superblock"); 795 goto unacquire_priv_sbp; 796 } 797 798 /* account for offset of super block on x86 */ 799 disk_sb = (befs_super_block *) bh->b_data; 800 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) || 801 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) { 802 befs_debug(sb, "Using PPC superblock location"); 803 } else { 804 befs_debug(sb, "Using x86 superblock location"); 805 disk_sb = 806 (befs_super_block *) ((void *) bh->b_data + x86_sb_off); 807 } 808 809 if ((befs_load_sb(sb, disk_sb) != BEFS_OK) || 810 (befs_check_sb(sb) != BEFS_OK)) 811 goto unacquire_bh; 812 813 befs_dump_super_block(sb, disk_sb); 814 815 brelse(bh); 816 817 if( befs_sb->num_blocks > ~((sector_t)0) ) { 818 if (!silent) 819 befs_error(sb, "blocks count: %llu is larger than the host can use", 820 befs_sb->num_blocks); 821 goto unacquire_priv_sbp; 822 } 823 824 /* 825 * set up enough so that it can read an inode 826 * Fill in kernel superblock fields from private sb 827 */ 828 sb->s_magic = BEFS_SUPER_MAGIC; 829 /* Set real blocksize of fs */ 830 sb_set_blocksize(sb, (ulong) befs_sb->block_size); 831 sb->s_op = &befs_sops; 832 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir))); 833 if (IS_ERR(root)) { 834 ret = PTR_ERR(root); 835 goto unacquire_priv_sbp; 836 } 837 sb->s_root = d_make_root(root); 838 if (!sb->s_root) { 839 if (!silent) 840 befs_error(sb, "get root inode failed"); 841 goto unacquire_priv_sbp; 842 } 843 844 /* load nls library */ 845 if (befs_sb->mount_opts.iocharset) { 846 befs_debug(sb, "Loading nls: %s", 847 befs_sb->mount_opts.iocharset); 848 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset); 849 if (!befs_sb->nls) { 850 befs_warning(sb, "Cannot load nls %s" 851 " loading default nls", 852 befs_sb->mount_opts.iocharset); 853 befs_sb->nls = load_nls_default(); 854 } 855 /* load default nls if none is specified in mount options */ 856 } else { 857 befs_debug(sb, "Loading default nls"); 858 befs_sb->nls = load_nls_default(); 859 } 860 861 return 0; 862 /*****************/ 863 unacquire_bh: 864 brelse(bh); 865 866 unacquire_priv_sbp: 867 kfree(befs_sb->mount_opts.iocharset); 868 kfree(sb->s_fs_info); 869 sb->s_fs_info = NULL; 870 871 unacquire_none: 872 return ret; 873 } 874 875 static int 876 befs_remount(struct super_block *sb, int *flags, char *data) 877 { 878 sync_filesystem(sb); 879 if (!(*flags & MS_RDONLY)) 880 return -EINVAL; 881 return 0; 882 } 883 884 static int 885 befs_statfs(struct dentry *dentry, struct kstatfs *buf) 886 { 887 struct super_block *sb = dentry->d_sb; 888 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 889 890 befs_debug(sb, "---> %s", __func__); 891 892 buf->f_type = BEFS_SUPER_MAGIC; 893 buf->f_bsize = sb->s_blocksize; 894 buf->f_blocks = BEFS_SB(sb)->num_blocks; 895 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks; 896 buf->f_bavail = buf->f_bfree; 897 buf->f_files = 0; /* UNKNOWN */ 898 buf->f_ffree = 0; /* UNKNOWN */ 899 buf->f_fsid.val[0] = (u32)id; 900 buf->f_fsid.val[1] = (u32)(id >> 32); 901 buf->f_namelen = BEFS_NAME_LEN; 902 903 befs_debug(sb, "<--- %s", __func__); 904 905 return 0; 906 } 907 908 static struct dentry * 909 befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, 910 void *data) 911 { 912 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super); 913 } 914 915 static struct file_system_type befs_fs_type = { 916 .owner = THIS_MODULE, 917 .name = "befs", 918 .mount = befs_mount, 919 .kill_sb = kill_block_super, 920 .fs_flags = FS_REQUIRES_DEV, 921 }; 922 MODULE_ALIAS_FS("befs"); 923 924 static int __init 925 init_befs_fs(void) 926 { 927 int err; 928 929 pr_info("version: %s\n", BEFS_VERSION); 930 931 err = befs_init_inodecache(); 932 if (err) 933 goto unacquire_none; 934 935 err = register_filesystem(&befs_fs_type); 936 if (err) 937 goto unacquire_inodecache; 938 939 return 0; 940 941 unacquire_inodecache: 942 befs_destroy_inodecache(); 943 944 unacquire_none: 945 return err; 946 } 947 948 static void __exit 949 exit_befs_fs(void) 950 { 951 befs_destroy_inodecache(); 952 953 unregister_filesystem(&befs_fs_type); 954 } 955 956 /* 957 Macros that typecheck the init and exit functions, 958 ensures that they are called at init and cleanup, 959 and eliminates warnings about unused functions. 960 */ 961 module_init(init_befs_fs) 962 module_exit(exit_befs_fs) 963