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 const char *befs_follow_link(struct dentry *, void **); 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 = 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 inode_operations befs_symlink_inode_operations = { 83 .readlink = generic_readlink, 84 .follow_link = befs_follow_link, 85 .put_link = kfree_put_link, 86 }; 87 88 /* 89 * Called by generic_file_read() to read a page of data 90 * 91 * In turn, simply calls a generic block read function and 92 * passes it the address of befs_get_block, for mapping file 93 * positions to disk blocks. 94 */ 95 static int 96 befs_readpage(struct file *file, struct page *page) 97 { 98 return block_read_full_page(page, befs_get_block); 99 } 100 101 static sector_t 102 befs_bmap(struct address_space *mapping, sector_t block) 103 { 104 return generic_block_bmap(mapping, block, befs_get_block); 105 } 106 107 /* 108 * Generic function to map a file position (block) to a 109 * disk offset (passed back in bh_result). 110 * 111 * Used by many higher level functions. 112 * 113 * Calls befs_fblock2brun() in datastream.c to do the real work. 114 * 115 * -WD 10-26-01 116 */ 117 118 static int 119 befs_get_block(struct inode *inode, sector_t block, 120 struct buffer_head *bh_result, int create) 121 { 122 struct super_block *sb = inode->i_sb; 123 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; 124 befs_block_run run = BAD_IADDR; 125 int res = 0; 126 ulong disk_off; 127 128 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld", 129 (unsigned long)inode->i_ino, (long)block); 130 if (create) { 131 befs_error(sb, "befs_get_block() was asked to write to " 132 "block %ld in inode %lu", (long)block, 133 (unsigned long)inode->i_ino); 134 return -EPERM; 135 } 136 137 res = befs_fblock2brun(sb, ds, block, &run); 138 if (res != BEFS_OK) { 139 befs_error(sb, 140 "<--- %s for inode %lu, block %ld ERROR", 141 __func__, (unsigned long)inode->i_ino, 142 (long)block); 143 return -EFBIG; 144 } 145 146 disk_off = (ulong) iaddr2blockno(sb, &run); 147 148 map_bh(bh_result, inode->i_sb, disk_off); 149 150 befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu", 151 __func__, (unsigned long)inode->i_ino, (long)block, 152 (unsigned long)disk_off); 153 154 return 0; 155 } 156 157 static struct dentry * 158 befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 159 { 160 struct inode *inode = NULL; 161 struct super_block *sb = dir->i_sb; 162 befs_data_stream *ds = &BEFS_I(dir)->i_data.ds; 163 befs_off_t offset; 164 int ret; 165 int utfnamelen; 166 char *utfname; 167 const char *name = dentry->d_name.name; 168 169 befs_debug(sb, "---> %s name %pd inode %ld", __func__, 170 dentry, dir->i_ino); 171 172 /* Convert to UTF-8 */ 173 if (BEFS_SB(sb)->nls) { 174 ret = 175 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen); 176 if (ret < 0) { 177 befs_debug(sb, "<--- %s ERROR", __func__); 178 return ERR_PTR(ret); 179 } 180 ret = befs_btree_find(sb, ds, utfname, &offset); 181 kfree(utfname); 182 183 } else { 184 ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset); 185 } 186 187 if (ret == BEFS_BT_NOT_FOUND) { 188 befs_debug(sb, "<--- %s %pd not found", __func__, dentry); 189 return ERR_PTR(-ENOENT); 190 191 } else if (ret != BEFS_OK || offset == 0) { 192 befs_warning(sb, "<--- %s Error", __func__); 193 return ERR_PTR(-ENODATA); 194 } 195 196 inode = befs_iget(dir->i_sb, (ino_t) offset); 197 if (IS_ERR(inode)) 198 return ERR_CAST(inode); 199 200 d_add(dentry, inode); 201 202 befs_debug(sb, "<--- %s", __func__); 203 204 return NULL; 205 } 206 207 static int 208 befs_readdir(struct file *file, struct dir_context *ctx) 209 { 210 struct inode *inode = file_inode(file); 211 struct super_block *sb = inode->i_sb; 212 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; 213 befs_off_t value; 214 int result; 215 size_t keysize; 216 unsigned char d_type; 217 char keybuf[BEFS_NAME_LEN + 1]; 218 219 befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld", 220 __func__, file, inode->i_ino, ctx->pos); 221 222 more: 223 result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1, 224 keybuf, &keysize, &value); 225 226 if (result == BEFS_ERR) { 227 befs_debug(sb, "<--- %s ERROR", __func__); 228 befs_error(sb, "IO error reading %pD (inode %lu)", 229 file, inode->i_ino); 230 return -EIO; 231 232 } else if (result == BEFS_BT_END) { 233 befs_debug(sb, "<--- %s END", __func__); 234 return 0; 235 236 } else if (result == BEFS_BT_EMPTY) { 237 befs_debug(sb, "<--- %s Empty directory", __func__); 238 return 0; 239 } 240 241 d_type = DT_UNKNOWN; 242 243 /* Convert to NLS */ 244 if (BEFS_SB(sb)->nls) { 245 char *nlsname; 246 int nlsnamelen; 247 result = 248 befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen); 249 if (result < 0) { 250 befs_debug(sb, "<--- %s ERROR", __func__); 251 return result; 252 } 253 if (!dir_emit(ctx, nlsname, nlsnamelen, 254 (ino_t) value, d_type)) { 255 kfree(nlsname); 256 return 0; 257 } 258 kfree(nlsname); 259 } else { 260 if (!dir_emit(ctx, keybuf, keysize, 261 (ino_t) value, d_type)) 262 return 0; 263 } 264 ctx->pos++; 265 goto more; 266 } 267 268 static struct inode * 269 befs_alloc_inode(struct super_block *sb) 270 { 271 struct befs_inode_info *bi; 272 273 bi = kmem_cache_alloc(befs_inode_cachep, GFP_KERNEL); 274 if (!bi) 275 return NULL; 276 return &bi->vfs_inode; 277 } 278 279 static void befs_i_callback(struct rcu_head *head) 280 { 281 struct inode *inode = container_of(head, struct inode, i_rcu); 282 kmem_cache_free(befs_inode_cachep, BEFS_I(inode)); 283 } 284 285 static void befs_destroy_inode(struct inode *inode) 286 { 287 call_rcu(&inode->i_rcu, befs_i_callback); 288 } 289 290 static void init_once(void *foo) 291 { 292 struct befs_inode_info *bi = (struct befs_inode_info *) foo; 293 294 inode_init_once(&bi->vfs_inode); 295 } 296 297 static struct inode *befs_iget(struct super_block *sb, unsigned long ino) 298 { 299 struct buffer_head *bh = NULL; 300 befs_inode *raw_inode = NULL; 301 struct befs_sb_info *befs_sb = BEFS_SB(sb); 302 struct befs_inode_info *befs_ino = NULL; 303 struct inode *inode; 304 long ret = -EIO; 305 306 befs_debug(sb, "---> %s inode = %lu", __func__, ino); 307 308 inode = iget_locked(sb, ino); 309 if (!inode) 310 return ERR_PTR(-ENOMEM); 311 if (!(inode->i_state & I_NEW)) 312 return inode; 313 314 befs_ino = BEFS_I(inode); 315 316 /* convert from vfs's inode number to befs's inode number */ 317 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino); 318 319 befs_debug(sb, " real inode number [%u, %hu, %hu]", 320 befs_ino->i_inode_num.allocation_group, 321 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len); 322 323 bh = befs_bread(sb, inode->i_ino); 324 if (!bh) { 325 befs_error(sb, "unable to read inode block - " 326 "inode = %lu", inode->i_ino); 327 goto unacquire_none; 328 } 329 330 raw_inode = (befs_inode *) bh->b_data; 331 332 befs_dump_inode(sb, raw_inode); 333 334 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) { 335 befs_error(sb, "Bad inode: %lu", inode->i_ino); 336 goto unacquire_bh; 337 } 338 339 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode); 340 341 /* 342 * set uid and gid. But since current BeOS is single user OS, so 343 * you can change by "uid" or "gid" options. 344 */ 345 346 inode->i_uid = befs_sb->mount_opts.use_uid ? 347 befs_sb->mount_opts.uid : 348 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid)); 349 inode->i_gid = befs_sb->mount_opts.use_gid ? 350 befs_sb->mount_opts.gid : 351 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid)); 352 353 set_nlink(inode, 1); 354 355 /* 356 * BEFS's time is 64 bits, but current VFS is 32 bits... 357 * BEFS don't have access time. Nor inode change time. VFS 358 * doesn't have creation time. 359 * Also, the lower 16 bits of the last_modified_time and 360 * create_time are just a counter to help ensure uniqueness 361 * for indexing purposes. (PFD, page 54) 362 */ 363 364 inode->i_mtime.tv_sec = 365 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16; 366 inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */ 367 inode->i_ctime = inode->i_mtime; 368 inode->i_atime = inode->i_mtime; 369 370 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num); 371 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent); 372 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes); 373 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags); 374 375 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){ 376 inode->i_size = 0; 377 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE; 378 strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink, 379 BEFS_SYMLINK_LEN); 380 } else { 381 int num_blks; 382 383 befs_ino->i_data.ds = 384 fsds_to_cpu(sb, &raw_inode->data.datastream); 385 386 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds); 387 inode->i_blocks = 388 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE); 389 inode->i_size = befs_ino->i_data.ds.size; 390 } 391 392 inode->i_mapping->a_ops = &befs_aops; 393 394 if (S_ISREG(inode->i_mode)) { 395 inode->i_fop = &generic_ro_fops; 396 } else if (S_ISDIR(inode->i_mode)) { 397 inode->i_op = &befs_dir_inode_operations; 398 inode->i_fop = &befs_dir_operations; 399 } else if (S_ISLNK(inode->i_mode)) { 400 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) { 401 inode->i_op = &befs_symlink_inode_operations; 402 } else { 403 inode->i_link = befs_ino->i_data.symlink; 404 inode->i_op = &simple_symlink_inode_operations; 405 } 406 } else { 407 befs_error(sb, "Inode %lu is not a regular file, " 408 "directory or symlink. THAT IS WRONG! BeFS has no " 409 "on disk special files", inode->i_ino); 410 goto unacquire_bh; 411 } 412 413 brelse(bh); 414 befs_debug(sb, "<--- %s", __func__); 415 unlock_new_inode(inode); 416 return inode; 417 418 unacquire_bh: 419 brelse(bh); 420 421 unacquire_none: 422 iget_failed(inode); 423 befs_debug(sb, "<--- %s - Bad inode", __func__); 424 return ERR_PTR(ret); 425 } 426 427 /* Initialize the inode cache. Called at fs setup. 428 * 429 * Taken from NFS implementation by Al Viro. 430 */ 431 static int __init 432 befs_init_inodecache(void) 433 { 434 befs_inode_cachep = kmem_cache_create("befs_inode_cache", 435 sizeof (struct befs_inode_info), 436 0, (SLAB_RECLAIM_ACCOUNT| 437 SLAB_MEM_SPREAD), 438 init_once); 439 if (befs_inode_cachep == NULL) { 440 pr_err("%s: Couldn't initialize inode slabcache\n", __func__); 441 return -ENOMEM; 442 } 443 return 0; 444 } 445 446 /* Called at fs teardown. 447 * 448 * Taken from NFS implementation by Al Viro. 449 */ 450 static void 451 befs_destroy_inodecache(void) 452 { 453 /* 454 * Make sure all delayed rcu free inodes are flushed before we 455 * destroy cache. 456 */ 457 rcu_barrier(); 458 kmem_cache_destroy(befs_inode_cachep); 459 } 460 461 /* 462 * The inode of symbolic link is different to data stream. 463 * The data stream become link name. Unless the LONG_SYMLINK 464 * flag is set. 465 */ 466 static const char * 467 befs_follow_link(struct dentry *dentry, void **cookie) 468 { 469 struct super_block *sb = dentry->d_sb; 470 struct befs_inode_info *befs_ino = BEFS_I(d_inode(dentry)); 471 befs_data_stream *data = &befs_ino->i_data.ds; 472 befs_off_t len = data->size; 473 char *link; 474 475 if (len == 0) { 476 befs_error(sb, "Long symlink with illegal length"); 477 return ERR_PTR(-EIO); 478 } 479 befs_debug(sb, "Follow long symlink"); 480 481 link = kmalloc(len, GFP_NOFS); 482 if (!link) 483 return ERR_PTR(-ENOMEM); 484 if (befs_read_lsymlink(sb, data, link, len) != len) { 485 kfree(link); 486 befs_error(sb, "Failed to read entire long symlink"); 487 return ERR_PTR(-EIO); 488 } 489 link[len - 1] = '\0'; 490 return *cookie = link; 491 } 492 493 /* 494 * UTF-8 to NLS charset convert routine 495 * 496 * 497 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than 498 * the nls tables directly 499 */ 500 501 static int 502 befs_utf2nls(struct super_block *sb, const char *in, 503 int in_len, char **out, int *out_len) 504 { 505 struct nls_table *nls = BEFS_SB(sb)->nls; 506 int i, o; 507 unicode_t uni; 508 int unilen, utflen; 509 char *result; 510 /* The utf8->nls conversion won't make the final nls string bigger 511 * than the utf one, but if the string is pure ascii they'll have the 512 * same width and an extra char is needed to save the additional \0 513 */ 514 int maxlen = in_len + 1; 515 516 befs_debug(sb, "---> %s", __func__); 517 518 if (!nls) { 519 befs_error(sb, "%s called with no NLS table loaded", __func__); 520 return -EINVAL; 521 } 522 523 *out = result = kmalloc(maxlen, GFP_NOFS); 524 if (!*out) { 525 befs_error(sb, "%s cannot allocate memory", __func__); 526 *out_len = 0; 527 return -ENOMEM; 528 } 529 530 for (i = o = 0; i < in_len; i += utflen, o += unilen) { 531 532 /* convert from UTF-8 to Unicode */ 533 utflen = utf8_to_utf32(&in[i], in_len - i, &uni); 534 if (utflen < 0) 535 goto conv_err; 536 537 /* convert from Unicode to nls */ 538 if (uni > MAX_WCHAR_T) 539 goto conv_err; 540 unilen = nls->uni2char(uni, &result[o], in_len - o); 541 if (unilen < 0) 542 goto conv_err; 543 } 544 result[o] = '\0'; 545 *out_len = o; 546 547 befs_debug(sb, "<--- %s", __func__); 548 549 return o; 550 551 conv_err: 552 befs_error(sb, "Name using character set %s contains a character that " 553 "cannot be converted to unicode.", nls->charset); 554 befs_debug(sb, "<--- %s", __func__); 555 kfree(result); 556 return -EILSEQ; 557 } 558 559 /** 560 * befs_nls2utf - Convert NLS string to utf8 encodeing 561 * @sb: Superblock 562 * @in: Input string buffer in NLS format 563 * @in_len: Length of input string in bytes 564 * @out: The output string in UTF-8 format 565 * @out_len: Length of the output buffer 566 * 567 * Converts input string @in, which is in the format of the loaded NLS map, 568 * into a utf8 string. 569 * 570 * The destination string @out is allocated by this function and the caller is 571 * responsible for freeing it with kfree() 572 * 573 * On return, *@out_len is the length of @out in bytes. 574 * 575 * On success, the return value is the number of utf8 characters written to 576 * the output buffer @out. 577 * 578 * On Failure, a negative number coresponding to the error code is returned. 579 */ 580 581 static int 582 befs_nls2utf(struct super_block *sb, const char *in, 583 int in_len, char **out, int *out_len) 584 { 585 struct nls_table *nls = BEFS_SB(sb)->nls; 586 int i, o; 587 wchar_t uni; 588 int unilen, utflen; 589 char *result; 590 /* There're nls characters that will translate to 3-chars-wide UTF-8 591 * characters, a additional byte is needed to save the final \0 592 * in special cases */ 593 int maxlen = (3 * in_len) + 1; 594 595 befs_debug(sb, "---> %s\n", __func__); 596 597 if (!nls) { 598 befs_error(sb, "%s called with no NLS table loaded.", 599 __func__); 600 return -EINVAL; 601 } 602 603 *out = result = kmalloc(maxlen, GFP_NOFS); 604 if (!*out) { 605 befs_error(sb, "%s cannot allocate memory", __func__); 606 *out_len = 0; 607 return -ENOMEM; 608 } 609 610 for (i = o = 0; i < in_len; i += unilen, o += utflen) { 611 612 /* convert from nls to unicode */ 613 unilen = nls->char2uni(&in[i], in_len - i, &uni); 614 if (unilen < 0) 615 goto conv_err; 616 617 /* convert from unicode to UTF-8 */ 618 utflen = utf32_to_utf8(uni, &result[o], 3); 619 if (utflen <= 0) 620 goto conv_err; 621 } 622 623 result[o] = '\0'; 624 *out_len = o; 625 626 befs_debug(sb, "<--- %s", __func__); 627 628 return i; 629 630 conv_err: 631 befs_error(sb, "Name using charecter set %s contains a charecter that " 632 "cannot be converted to unicode.", nls->charset); 633 befs_debug(sb, "<--- %s", __func__); 634 kfree(result); 635 return -EILSEQ; 636 } 637 638 /** 639 * Use the 640 * 641 */ 642 enum { 643 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err, 644 }; 645 646 static const match_table_t befs_tokens = { 647 {Opt_uid, "uid=%d"}, 648 {Opt_gid, "gid=%d"}, 649 {Opt_charset, "iocharset=%s"}, 650 {Opt_debug, "debug"}, 651 {Opt_err, NULL} 652 }; 653 654 static int 655 parse_options(char *options, struct befs_mount_options *opts) 656 { 657 char *p; 658 substring_t args[MAX_OPT_ARGS]; 659 int option; 660 kuid_t uid; 661 kgid_t gid; 662 663 /* Initialize options */ 664 opts->uid = GLOBAL_ROOT_UID; 665 opts->gid = GLOBAL_ROOT_GID; 666 opts->use_uid = 0; 667 opts->use_gid = 0; 668 opts->iocharset = NULL; 669 opts->debug = 0; 670 671 if (!options) 672 return 1; 673 674 while ((p = strsep(&options, ",")) != NULL) { 675 int token; 676 if (!*p) 677 continue; 678 679 token = match_token(p, befs_tokens, args); 680 switch (token) { 681 case Opt_uid: 682 if (match_int(&args[0], &option)) 683 return 0; 684 uid = INVALID_UID; 685 if (option >= 0) 686 uid = make_kuid(current_user_ns(), option); 687 if (!uid_valid(uid)) { 688 pr_err("Invalid uid %d, " 689 "using default\n", option); 690 break; 691 } 692 opts->uid = uid; 693 opts->use_uid = 1; 694 break; 695 case Opt_gid: 696 if (match_int(&args[0], &option)) 697 return 0; 698 gid = INVALID_GID; 699 if (option >= 0) 700 gid = make_kgid(current_user_ns(), option); 701 if (!gid_valid(gid)) { 702 pr_err("Invalid gid %d, " 703 "using default\n", option); 704 break; 705 } 706 opts->gid = gid; 707 opts->use_gid = 1; 708 break; 709 case Opt_charset: 710 kfree(opts->iocharset); 711 opts->iocharset = match_strdup(&args[0]); 712 if (!opts->iocharset) { 713 pr_err("allocation failure for " 714 "iocharset string\n"); 715 return 0; 716 } 717 break; 718 case Opt_debug: 719 opts->debug = 1; 720 break; 721 default: 722 pr_err("Unrecognized mount option \"%s\" " 723 "or missing value\n", p); 724 return 0; 725 } 726 } 727 return 1; 728 } 729 730 /* This function has the responsibiltiy of getting the 731 * filesystem ready for unmounting. 732 * Basically, we free everything that we allocated in 733 * befs_read_inode 734 */ 735 static void 736 befs_put_super(struct super_block *sb) 737 { 738 kfree(BEFS_SB(sb)->mount_opts.iocharset); 739 BEFS_SB(sb)->mount_opts.iocharset = NULL; 740 unload_nls(BEFS_SB(sb)->nls); 741 kfree(sb->s_fs_info); 742 sb->s_fs_info = NULL; 743 } 744 745 /* Allocate private field of the superblock, fill it. 746 * 747 * Finish filling the public superblock fields 748 * Make the root directory 749 * Load a set of NLS translations if needed. 750 */ 751 static int 752 befs_fill_super(struct super_block *sb, void *data, int silent) 753 { 754 struct buffer_head *bh; 755 struct befs_sb_info *befs_sb; 756 befs_super_block *disk_sb; 757 struct inode *root; 758 long ret = -EINVAL; 759 const unsigned long sb_block = 0; 760 const off_t x86_sb_off = 512; 761 762 save_mount_options(sb, data); 763 764 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL); 765 if (sb->s_fs_info == NULL) { 766 pr_err("(%s): Unable to allocate memory for private " 767 "portion of superblock. Bailing.\n", sb->s_id); 768 goto unacquire_none; 769 } 770 befs_sb = BEFS_SB(sb); 771 772 if (!parse_options((char *) data, &befs_sb->mount_opts)) { 773 befs_error(sb, "cannot parse mount options"); 774 goto unacquire_priv_sbp; 775 } 776 777 befs_debug(sb, "---> %s", __func__); 778 779 if (!(sb->s_flags & MS_RDONLY)) { 780 befs_warning(sb, 781 "No write support. Marking filesystem read-only"); 782 sb->s_flags |= MS_RDONLY; 783 } 784 785 /* 786 * Set dummy blocksize to read super block. 787 * Will be set to real fs blocksize later. 788 * 789 * Linux 2.4.10 and later refuse to read blocks smaller than 790 * the hardsect size for the device. But we also need to read at 791 * least 1k to get the second 512 bytes of the volume. 792 * -WD 10-26-01 793 */ 794 sb_min_blocksize(sb, 1024); 795 796 if (!(bh = sb_bread(sb, sb_block))) { 797 befs_error(sb, "unable to read superblock"); 798 goto unacquire_priv_sbp; 799 } 800 801 /* account for offset of super block on x86 */ 802 disk_sb = (befs_super_block *) bh->b_data; 803 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) || 804 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) { 805 befs_debug(sb, "Using PPC superblock location"); 806 } else { 807 befs_debug(sb, "Using x86 superblock location"); 808 disk_sb = 809 (befs_super_block *) ((void *) bh->b_data + x86_sb_off); 810 } 811 812 if ((befs_load_sb(sb, disk_sb) != BEFS_OK) || 813 (befs_check_sb(sb) != BEFS_OK)) 814 goto unacquire_bh; 815 816 befs_dump_super_block(sb, disk_sb); 817 818 brelse(bh); 819 820 if( befs_sb->num_blocks > ~((sector_t)0) ) { 821 befs_error(sb, "blocks count: %llu " 822 "is larger than the host can use", 823 befs_sb->num_blocks); 824 goto unacquire_priv_sbp; 825 } 826 827 /* 828 * set up enough so that it can read an inode 829 * Fill in kernel superblock fields from private sb 830 */ 831 sb->s_magic = BEFS_SUPER_MAGIC; 832 /* Set real blocksize of fs */ 833 sb_set_blocksize(sb, (ulong) befs_sb->block_size); 834 sb->s_op = &befs_sops; 835 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir))); 836 if (IS_ERR(root)) { 837 ret = PTR_ERR(root); 838 goto unacquire_priv_sbp; 839 } 840 sb->s_root = d_make_root(root); 841 if (!sb->s_root) { 842 befs_error(sb, "get root inode failed"); 843 goto unacquire_priv_sbp; 844 } 845 846 /* load nls library */ 847 if (befs_sb->mount_opts.iocharset) { 848 befs_debug(sb, "Loading nls: %s", 849 befs_sb->mount_opts.iocharset); 850 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset); 851 if (!befs_sb->nls) { 852 befs_warning(sb, "Cannot load nls %s" 853 " loading default nls", 854 befs_sb->mount_opts.iocharset); 855 befs_sb->nls = load_nls_default(); 856 } 857 /* load default nls if none is specified in mount options */ 858 } else { 859 befs_debug(sb, "Loading default nls"); 860 befs_sb->nls = load_nls_default(); 861 } 862 863 return 0; 864 /*****************/ 865 unacquire_bh: 866 brelse(bh); 867 868 unacquire_priv_sbp: 869 kfree(befs_sb->mount_opts.iocharset); 870 kfree(sb->s_fs_info); 871 872 unacquire_none: 873 sb->s_fs_info = NULL; 874 return ret; 875 } 876 877 static int 878 befs_remount(struct super_block *sb, int *flags, char *data) 879 { 880 sync_filesystem(sb); 881 if (!(*flags & MS_RDONLY)) 882 return -EINVAL; 883 return 0; 884 } 885 886 static int 887 befs_statfs(struct dentry *dentry, struct kstatfs *buf) 888 { 889 struct super_block *sb = dentry->d_sb; 890 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 891 892 befs_debug(sb, "---> %s", __func__); 893 894 buf->f_type = BEFS_SUPER_MAGIC; 895 buf->f_bsize = sb->s_blocksize; 896 buf->f_blocks = BEFS_SB(sb)->num_blocks; 897 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks; 898 buf->f_bavail = buf->f_bfree; 899 buf->f_files = 0; /* UNKNOWN */ 900 buf->f_ffree = 0; /* UNKNOWN */ 901 buf->f_fsid.val[0] = (u32)id; 902 buf->f_fsid.val[1] = (u32)(id >> 32); 903 buf->f_namelen = BEFS_NAME_LEN; 904 905 befs_debug(sb, "<--- %s", __func__); 906 907 return 0; 908 } 909 910 static struct dentry * 911 befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, 912 void *data) 913 { 914 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super); 915 } 916 917 static struct file_system_type befs_fs_type = { 918 .owner = THIS_MODULE, 919 .name = "befs", 920 .mount = befs_mount, 921 .kill_sb = kill_block_super, 922 .fs_flags = FS_REQUIRES_DEV, 923 }; 924 MODULE_ALIAS_FS("befs"); 925 926 static int __init 927 init_befs_fs(void) 928 { 929 int err; 930 931 pr_info("version: %s\n", BEFS_VERSION); 932 933 err = befs_init_inodecache(); 934 if (err) 935 goto unacquire_none; 936 937 err = register_filesystem(&befs_fs_type); 938 if (err) 939 goto unacquire_inodecache; 940 941 return 0; 942 943 unacquire_inodecache: 944 befs_destroy_inodecache(); 945 946 unacquire_none: 947 return err; 948 } 949 950 static void __exit 951 exit_befs_fs(void) 952 { 953 befs_destroy_inodecache(); 954 955 unregister_filesystem(&befs_fs_type); 956 } 957 958 /* 959 Macros that typecheck the init and exit functions, 960 ensures that they are called at init and cleanup, 961 and eliminates warnings about unused functions. 962 */ 963 module_init(init_befs_fs) 964 module_exit(exit_befs_fs) 965