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 #include <linux/exportfs.h> 22 23 #include "befs.h" 24 #include "btree.h" 25 #include "inode.h" 26 #include "datastream.h" 27 #include "super.h" 28 #include "io.h" 29 30 MODULE_DESCRIPTION("BeOS File System (BeFS) driver"); 31 MODULE_AUTHOR("Will Dyson"); 32 MODULE_LICENSE("GPL"); 33 34 /* The units the vfs expects inode->i_blocks to be in */ 35 #define VFS_BLOCK_SIZE 512 36 37 static int befs_readdir(struct file *, struct dir_context *); 38 static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int); 39 static int befs_readpage(struct file *file, struct page *page); 40 static sector_t befs_bmap(struct address_space *mapping, sector_t block); 41 static struct dentry *befs_lookup(struct inode *, struct dentry *, 42 unsigned int); 43 static struct inode *befs_iget(struct super_block *, unsigned long); 44 static struct inode *befs_alloc_inode(struct super_block *sb); 45 static void befs_destroy_inode(struct inode *inode); 46 static void befs_destroy_inodecache(void); 47 static int befs_symlink_readpage(struct file *, struct page *); 48 static int befs_utf2nls(struct super_block *sb, const char *in, int in_len, 49 char **out, int *out_len); 50 static int befs_nls2utf(struct super_block *sb, const char *in, int in_len, 51 char **out, int *out_len); 52 static void befs_put_super(struct super_block *); 53 static int befs_remount(struct super_block *, int *, char *); 54 static int befs_statfs(struct dentry *, struct kstatfs *); 55 static int parse_options(char *, struct befs_mount_options *); 56 static struct dentry *befs_fh_to_dentry(struct super_block *sb, 57 struct fid *fid, int fh_len, int fh_type); 58 static struct dentry *befs_fh_to_parent(struct super_block *sb, 59 struct fid *fid, int fh_len, int fh_type); 60 61 static const struct super_operations befs_sops = { 62 .alloc_inode = befs_alloc_inode, /* allocate a new inode */ 63 .destroy_inode = befs_destroy_inode, /* deallocate an inode */ 64 .put_super = befs_put_super, /* uninit super */ 65 .statfs = befs_statfs, /* statfs */ 66 .remount_fs = befs_remount, 67 .show_options = generic_show_options, 68 }; 69 70 /* slab cache for befs_inode_info objects */ 71 static struct kmem_cache *befs_inode_cachep; 72 73 static const struct file_operations befs_dir_operations = { 74 .read = generic_read_dir, 75 .iterate_shared = befs_readdir, 76 .llseek = generic_file_llseek, 77 }; 78 79 static const struct inode_operations befs_dir_inode_operations = { 80 .lookup = befs_lookup, 81 }; 82 83 static const struct address_space_operations befs_aops = { 84 .readpage = befs_readpage, 85 .bmap = befs_bmap, 86 }; 87 88 static const struct address_space_operations befs_symlink_aops = { 89 .readpage = befs_symlink_readpage, 90 }; 91 92 static const struct export_operations befs_export_operations = { 93 .fh_to_dentry = befs_fh_to_dentry, 94 .fh_to_parent = befs_fh_to_parent, 95 }; 96 97 /* 98 * Called by generic_file_read() to read a page of data 99 * 100 * In turn, simply calls a generic block read function and 101 * passes it the address of befs_get_block, for mapping file 102 * positions to disk blocks. 103 */ 104 static int 105 befs_readpage(struct file *file, struct page *page) 106 { 107 return block_read_full_page(page, befs_get_block); 108 } 109 110 static sector_t 111 befs_bmap(struct address_space *mapping, sector_t block) 112 { 113 return generic_block_bmap(mapping, block, befs_get_block); 114 } 115 116 /* 117 * Generic function to map a file position (block) to a 118 * disk offset (passed back in bh_result). 119 * 120 * Used by many higher level functions. 121 * 122 * Calls befs_fblock2brun() in datastream.c to do the real work. 123 */ 124 125 static int 126 befs_get_block(struct inode *inode, sector_t block, 127 struct buffer_head *bh_result, int create) 128 { 129 struct super_block *sb = inode->i_sb; 130 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; 131 befs_block_run run = BAD_IADDR; 132 int res; 133 ulong disk_off; 134 135 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld", 136 (unsigned long)inode->i_ino, (long)block); 137 if (create) { 138 befs_error(sb, "befs_get_block() was asked to write to " 139 "block %ld in inode %lu", (long)block, 140 (unsigned long)inode->i_ino); 141 return -EPERM; 142 } 143 144 res = befs_fblock2brun(sb, ds, block, &run); 145 if (res != BEFS_OK) { 146 befs_error(sb, 147 "<--- %s for inode %lu, block %ld ERROR", 148 __func__, (unsigned long)inode->i_ino, 149 (long)block); 150 return -EFBIG; 151 } 152 153 disk_off = (ulong) iaddr2blockno(sb, &run); 154 155 map_bh(bh_result, inode->i_sb, disk_off); 156 157 befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu", 158 __func__, (unsigned long)inode->i_ino, (long)block, 159 (unsigned long)disk_off); 160 161 return 0; 162 } 163 164 static struct dentry * 165 befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 166 { 167 struct inode *inode; 168 struct super_block *sb = dir->i_sb; 169 const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds; 170 befs_off_t offset; 171 int ret; 172 int utfnamelen; 173 char *utfname; 174 const char *name = dentry->d_name.name; 175 176 befs_debug(sb, "---> %s name %pd inode %ld", __func__, 177 dentry, dir->i_ino); 178 179 /* Convert to UTF-8 */ 180 if (BEFS_SB(sb)->nls) { 181 ret = 182 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen); 183 if (ret < 0) { 184 befs_debug(sb, "<--- %s ERROR", __func__); 185 return ERR_PTR(ret); 186 } 187 ret = befs_btree_find(sb, ds, utfname, &offset); 188 kfree(utfname); 189 190 } else { 191 ret = befs_btree_find(sb, ds, name, &offset); 192 } 193 194 if (ret == BEFS_BT_NOT_FOUND) { 195 befs_debug(sb, "<--- %s %pd not found", __func__, dentry); 196 d_add(dentry, NULL); 197 return ERR_PTR(-ENOENT); 198 199 } else if (ret != BEFS_OK || offset == 0) { 200 befs_error(sb, "<--- %s Error", __func__); 201 return ERR_PTR(-ENODATA); 202 } 203 204 inode = befs_iget(dir->i_sb, (ino_t) offset); 205 if (IS_ERR(inode)) 206 return ERR_CAST(inode); 207 208 d_add(dentry, inode); 209 210 befs_debug(sb, "<--- %s", __func__); 211 212 return NULL; 213 } 214 215 static int 216 befs_readdir(struct file *file, struct dir_context *ctx) 217 { 218 struct inode *inode = file_inode(file); 219 struct super_block *sb = inode->i_sb; 220 const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds; 221 befs_off_t value; 222 int result; 223 size_t keysize; 224 char keybuf[BEFS_NAME_LEN + 1]; 225 226 befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld", 227 __func__, file, inode->i_ino, ctx->pos); 228 229 while (1) { 230 result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1, 231 keybuf, &keysize, &value); 232 233 if (result == BEFS_ERR) { 234 befs_debug(sb, "<--- %s ERROR", __func__); 235 befs_error(sb, "IO error reading %pD (inode %lu)", 236 file, inode->i_ino); 237 return -EIO; 238 239 } else if (result == BEFS_BT_END) { 240 befs_debug(sb, "<--- %s END", __func__); 241 return 0; 242 243 } else if (result == BEFS_BT_EMPTY) { 244 befs_debug(sb, "<--- %s Empty directory", __func__); 245 return 0; 246 } 247 248 /* Convert to NLS */ 249 if (BEFS_SB(sb)->nls) { 250 char *nlsname; 251 int nlsnamelen; 252 253 result = 254 befs_utf2nls(sb, keybuf, keysize, &nlsname, 255 &nlsnamelen); 256 if (result < 0) { 257 befs_debug(sb, "<--- %s ERROR", __func__); 258 return result; 259 } 260 if (!dir_emit(ctx, nlsname, nlsnamelen, 261 (ino_t) value, DT_UNKNOWN)) { 262 kfree(nlsname); 263 return 0; 264 } 265 kfree(nlsname); 266 } else { 267 if (!dir_emit(ctx, keybuf, keysize, 268 (ino_t) value, DT_UNKNOWN)) 269 return 0; 270 } 271 ctx->pos++; 272 } 273 } 274 275 static struct inode * 276 befs_alloc_inode(struct super_block *sb) 277 { 278 struct befs_inode_info *bi; 279 280 bi = kmem_cache_alloc(befs_inode_cachep, GFP_KERNEL); 281 if (!bi) 282 return NULL; 283 return &bi->vfs_inode; 284 } 285 286 static void befs_i_callback(struct rcu_head *head) 287 { 288 struct inode *inode = container_of(head, struct inode, i_rcu); 289 kmem_cache_free(befs_inode_cachep, BEFS_I(inode)); 290 } 291 292 static void befs_destroy_inode(struct inode *inode) 293 { 294 call_rcu(&inode->i_rcu, befs_i_callback); 295 } 296 297 static void init_once(void *foo) 298 { 299 struct befs_inode_info *bi = (struct befs_inode_info *) foo; 300 301 inode_init_once(&bi->vfs_inode); 302 } 303 304 static struct inode *befs_iget(struct super_block *sb, unsigned long ino) 305 { 306 struct buffer_head *bh; 307 befs_inode *raw_inode; 308 struct befs_sb_info *befs_sb = BEFS_SB(sb); 309 struct befs_inode_info *befs_ino; 310 struct inode *inode; 311 312 befs_debug(sb, "---> %s inode = %lu", __func__, ino); 313 314 inode = iget_locked(sb, ino); 315 if (!inode) 316 return ERR_PTR(-ENOMEM); 317 if (!(inode->i_state & I_NEW)) 318 return inode; 319 320 befs_ino = BEFS_I(inode); 321 322 /* convert from vfs's inode number to befs's inode number */ 323 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino); 324 325 befs_debug(sb, " real inode number [%u, %hu, %hu]", 326 befs_ino->i_inode_num.allocation_group, 327 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len); 328 329 bh = sb_bread(sb, inode->i_ino); 330 if (!bh) { 331 befs_error(sb, "unable to read inode block - " 332 "inode = %lu", inode->i_ino); 333 goto unacquire_none; 334 } 335 336 raw_inode = (befs_inode *) bh->b_data; 337 338 befs_dump_inode(sb, raw_inode); 339 340 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) { 341 befs_error(sb, "Bad inode: %lu", inode->i_ino); 342 goto unacquire_bh; 343 } 344 345 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode); 346 347 /* 348 * set uid and gid. But since current BeOS is single user OS, so 349 * you can change by "uid" or "gid" options. 350 */ 351 352 inode->i_uid = befs_sb->mount_opts.use_uid ? 353 befs_sb->mount_opts.uid : 354 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid)); 355 inode->i_gid = befs_sb->mount_opts.use_gid ? 356 befs_sb->mount_opts.gid : 357 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid)); 358 359 set_nlink(inode, 1); 360 361 /* 362 * BEFS's time is 64 bits, but current VFS is 32 bits... 363 * BEFS don't have access time. Nor inode change time. VFS 364 * doesn't have creation time. 365 * Also, the lower 16 bits of the last_modified_time and 366 * create_time are just a counter to help ensure uniqueness 367 * for indexing purposes. (PFD, page 54) 368 */ 369 370 inode->i_mtime.tv_sec = 371 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16; 372 inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */ 373 inode->i_ctime = inode->i_mtime; 374 inode->i_atime = inode->i_mtime; 375 376 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num); 377 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent); 378 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes); 379 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags); 380 381 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){ 382 inode->i_size = 0; 383 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE; 384 strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink, 385 BEFS_SYMLINK_LEN); 386 } else { 387 int num_blks; 388 389 befs_ino->i_data.ds = 390 fsds_to_cpu(sb, &raw_inode->data.datastream); 391 392 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds); 393 inode->i_blocks = 394 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE); 395 inode->i_size = befs_ino->i_data.ds.size; 396 } 397 398 inode->i_mapping->a_ops = &befs_aops; 399 400 if (S_ISREG(inode->i_mode)) { 401 inode->i_fop = &generic_ro_fops; 402 } else if (S_ISDIR(inode->i_mode)) { 403 inode->i_op = &befs_dir_inode_operations; 404 inode->i_fop = &befs_dir_operations; 405 } else if (S_ISLNK(inode->i_mode)) { 406 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) { 407 inode->i_op = &page_symlink_inode_operations; 408 inode_nohighmem(inode); 409 inode->i_mapping->a_ops = &befs_symlink_aops; 410 } else { 411 inode->i_link = befs_ino->i_data.symlink; 412 inode->i_op = &simple_symlink_inode_operations; 413 } 414 } else { 415 befs_error(sb, "Inode %lu is not a regular file, " 416 "directory or symlink. THAT IS WRONG! BeFS has no " 417 "on disk special files", inode->i_ino); 418 goto unacquire_bh; 419 } 420 421 brelse(bh); 422 befs_debug(sb, "<--- %s", __func__); 423 unlock_new_inode(inode); 424 return inode; 425 426 unacquire_bh: 427 brelse(bh); 428 429 unacquire_none: 430 iget_failed(inode); 431 befs_debug(sb, "<--- %s - Bad inode", __func__); 432 return ERR_PTR(-EIO); 433 } 434 435 /* Initialize the inode cache. Called at fs setup. 436 * 437 * Taken from NFS implementation by Al Viro. 438 */ 439 static int __init 440 befs_init_inodecache(void) 441 { 442 befs_inode_cachep = kmem_cache_create("befs_inode_cache", 443 sizeof (struct befs_inode_info), 444 0, (SLAB_RECLAIM_ACCOUNT| 445 SLAB_MEM_SPREAD|SLAB_ACCOUNT), 446 init_once); 447 if (befs_inode_cachep == NULL) 448 return -ENOMEM; 449 450 return 0; 451 } 452 453 /* Called at fs teardown. 454 * 455 * Taken from NFS implementation by Al Viro. 456 */ 457 static void 458 befs_destroy_inodecache(void) 459 { 460 /* 461 * Make sure all delayed rcu free inodes are flushed before we 462 * destroy cache. 463 */ 464 rcu_barrier(); 465 kmem_cache_destroy(befs_inode_cachep); 466 } 467 468 /* 469 * The inode of symbolic link is different to data stream. 470 * The data stream become link name. Unless the LONG_SYMLINK 471 * flag is set. 472 */ 473 static int befs_symlink_readpage(struct file *unused, struct page *page) 474 { 475 struct inode *inode = page->mapping->host; 476 struct super_block *sb = inode->i_sb; 477 struct befs_inode_info *befs_ino = BEFS_I(inode); 478 befs_data_stream *data = &befs_ino->i_data.ds; 479 befs_off_t len = data->size; 480 char *link = page_address(page); 481 482 if (len == 0 || len > PAGE_SIZE) { 483 befs_error(sb, "Long symlink with illegal length"); 484 goto fail; 485 } 486 befs_debug(sb, "Follow long symlink"); 487 488 if (befs_read_lsymlink(sb, data, link, len) != len) { 489 befs_error(sb, "Failed to read entire long symlink"); 490 goto fail; 491 } 492 link[len - 1] = '\0'; 493 SetPageUptodate(page); 494 unlock_page(page); 495 return 0; 496 fail: 497 SetPageError(page); 498 unlock_page(page); 499 return -EIO; 500 } 501 502 /* 503 * UTF-8 to NLS charset convert routine 504 * 505 * Uses uni2char() / char2uni() rather than the nls tables directly 506 */ 507 static int 508 befs_utf2nls(struct super_block *sb, const char *in, 509 int in_len, char **out, int *out_len) 510 { 511 struct nls_table *nls = BEFS_SB(sb)->nls; 512 int i, o; 513 unicode_t uni; 514 int unilen, utflen; 515 char *result; 516 /* The utf8->nls conversion won't make the final nls string bigger 517 * than the utf one, but if the string is pure ascii they'll have the 518 * same width and an extra char is needed to save the additional \0 519 */ 520 int maxlen = in_len + 1; 521 522 befs_debug(sb, "---> %s", __func__); 523 524 if (!nls) { 525 befs_error(sb, "%s called with no NLS table loaded", __func__); 526 return -EINVAL; 527 } 528 529 *out = result = kmalloc(maxlen, GFP_NOFS); 530 if (!*out) 531 return -ENOMEM; 532 533 for (i = o = 0; i < in_len; i += utflen, o += unilen) { 534 535 /* convert from UTF-8 to Unicode */ 536 utflen = utf8_to_utf32(&in[i], in_len - i, &uni); 537 if (utflen < 0) 538 goto conv_err; 539 540 /* convert from Unicode to nls */ 541 if (uni > MAX_WCHAR_T) 542 goto conv_err; 543 unilen = nls->uni2char(uni, &result[o], in_len - o); 544 if (unilen < 0) 545 goto conv_err; 546 } 547 result[o] = '\0'; 548 *out_len = o; 549 550 befs_debug(sb, "<--- %s", __func__); 551 552 return o; 553 554 conv_err: 555 befs_error(sb, "Name using character set %s contains a character that " 556 "cannot be converted to unicode.", nls->charset); 557 befs_debug(sb, "<--- %s", __func__); 558 kfree(result); 559 return -EILSEQ; 560 } 561 562 /** 563 * befs_nls2utf - Convert NLS string to utf8 encodeing 564 * @sb: Superblock 565 * @in: Input string buffer in NLS format 566 * @in_len: Length of input string in bytes 567 * @out: The output string in UTF-8 format 568 * @out_len: Length of the output buffer 569 * 570 * Converts input string @in, which is in the format of the loaded NLS map, 571 * into a utf8 string. 572 * 573 * The destination string @out is allocated by this function and the caller is 574 * responsible for freeing it with kfree() 575 * 576 * On return, *@out_len is the length of @out in bytes. 577 * 578 * On success, the return value is the number of utf8 characters written to 579 * the output buffer @out. 580 * 581 * On Failure, a negative number coresponding to the error code is returned. 582 */ 583 584 static int 585 befs_nls2utf(struct super_block *sb, const char *in, 586 int in_len, char **out, int *out_len) 587 { 588 struct nls_table *nls = BEFS_SB(sb)->nls; 589 int i, o; 590 wchar_t uni; 591 int unilen, utflen; 592 char *result; 593 /* 594 * There are nls characters that will translate to 3-chars-wide UTF-8 595 * characters, an additional byte is needed to save the final \0 596 * in special cases 597 */ 598 int maxlen = (3 * in_len) + 1; 599 600 befs_debug(sb, "---> %s\n", __func__); 601 602 if (!nls) { 603 befs_error(sb, "%s called with no NLS table loaded.", 604 __func__); 605 return -EINVAL; 606 } 607 608 *out = result = kmalloc(maxlen, GFP_NOFS); 609 if (!*out) { 610 *out_len = 0; 611 return -ENOMEM; 612 } 613 614 for (i = o = 0; i < in_len; i += unilen, o += utflen) { 615 616 /* convert from nls to unicode */ 617 unilen = nls->char2uni(&in[i], in_len - i, &uni); 618 if (unilen < 0) 619 goto conv_err; 620 621 /* convert from unicode to UTF-8 */ 622 utflen = utf32_to_utf8(uni, &result[o], 3); 623 if (utflen <= 0) 624 goto conv_err; 625 } 626 627 result[o] = '\0'; 628 *out_len = o; 629 630 befs_debug(sb, "<--- %s", __func__); 631 632 return i; 633 634 conv_err: 635 befs_error(sb, "Name using character set %s contains a character that " 636 "cannot be converted to unicode.", nls->charset); 637 befs_debug(sb, "<--- %s", __func__); 638 kfree(result); 639 return -EILSEQ; 640 } 641 642 static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino, 643 uint32_t generation) 644 { 645 /* No need to handle i_generation */ 646 return befs_iget(sb, ino); 647 } 648 649 /* 650 * Map a NFS file handle to a corresponding dentry 651 */ 652 static struct dentry *befs_fh_to_dentry(struct super_block *sb, 653 struct fid *fid, int fh_len, int fh_type) 654 { 655 return generic_fh_to_dentry(sb, fid, fh_len, fh_type, 656 befs_nfs_get_inode); 657 } 658 659 /* 660 * Find the parent for a file specified by NFS handle 661 */ 662 static struct dentry *befs_fh_to_parent(struct super_block *sb, 663 struct fid *fid, int fh_len, int fh_type) 664 { 665 return generic_fh_to_parent(sb, fid, fh_len, fh_type, 666 befs_nfs_get_inode); 667 } 668 669 enum { 670 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err, 671 }; 672 673 static const match_table_t befs_tokens = { 674 {Opt_uid, "uid=%d"}, 675 {Opt_gid, "gid=%d"}, 676 {Opt_charset, "iocharset=%s"}, 677 {Opt_debug, "debug"}, 678 {Opt_err, NULL} 679 }; 680 681 static int 682 parse_options(char *options, struct befs_mount_options *opts) 683 { 684 char *p; 685 substring_t args[MAX_OPT_ARGS]; 686 int option; 687 kuid_t uid; 688 kgid_t gid; 689 690 /* Initialize options */ 691 opts->uid = GLOBAL_ROOT_UID; 692 opts->gid = GLOBAL_ROOT_GID; 693 opts->use_uid = 0; 694 opts->use_gid = 0; 695 opts->iocharset = NULL; 696 opts->debug = 0; 697 698 if (!options) 699 return 1; 700 701 while ((p = strsep(&options, ",")) != NULL) { 702 int token; 703 704 if (!*p) 705 continue; 706 707 token = match_token(p, befs_tokens, args); 708 switch (token) { 709 case Opt_uid: 710 if (match_int(&args[0], &option)) 711 return 0; 712 uid = INVALID_UID; 713 if (option >= 0) 714 uid = make_kuid(current_user_ns(), option); 715 if (!uid_valid(uid)) { 716 pr_err("Invalid uid %d, " 717 "using default\n", option); 718 break; 719 } 720 opts->uid = uid; 721 opts->use_uid = 1; 722 break; 723 case Opt_gid: 724 if (match_int(&args[0], &option)) 725 return 0; 726 gid = INVALID_GID; 727 if (option >= 0) 728 gid = make_kgid(current_user_ns(), option); 729 if (!gid_valid(gid)) { 730 pr_err("Invalid gid %d, " 731 "using default\n", option); 732 break; 733 } 734 opts->gid = gid; 735 opts->use_gid = 1; 736 break; 737 case Opt_charset: 738 kfree(opts->iocharset); 739 opts->iocharset = match_strdup(&args[0]); 740 if (!opts->iocharset) { 741 pr_err("allocation failure for " 742 "iocharset string\n"); 743 return 0; 744 } 745 break; 746 case Opt_debug: 747 opts->debug = 1; 748 break; 749 default: 750 pr_err("Unrecognized mount option \"%s\" " 751 "or missing value\n", p); 752 return 0; 753 } 754 } 755 return 1; 756 } 757 758 /* This function has the responsibiltiy of getting the 759 * filesystem ready for unmounting. 760 * Basically, we free everything that we allocated in 761 * befs_read_inode 762 */ 763 static void 764 befs_put_super(struct super_block *sb) 765 { 766 kfree(BEFS_SB(sb)->mount_opts.iocharset); 767 BEFS_SB(sb)->mount_opts.iocharset = NULL; 768 unload_nls(BEFS_SB(sb)->nls); 769 kfree(sb->s_fs_info); 770 sb->s_fs_info = NULL; 771 } 772 773 /* Allocate private field of the superblock, fill it. 774 * 775 * Finish filling the public superblock fields 776 * Make the root directory 777 * Load a set of NLS translations if needed. 778 */ 779 static int 780 befs_fill_super(struct super_block *sb, void *data, int silent) 781 { 782 struct buffer_head *bh; 783 struct befs_sb_info *befs_sb; 784 befs_super_block *disk_sb; 785 struct inode *root; 786 long ret = -EINVAL; 787 const unsigned long sb_block = 0; 788 const off_t x86_sb_off = 512; 789 int blocksize; 790 791 save_mount_options(sb, data); 792 793 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL); 794 if (sb->s_fs_info == NULL) 795 goto unacquire_none; 796 797 befs_sb = BEFS_SB(sb); 798 799 if (!parse_options((char *) data, &befs_sb->mount_opts)) { 800 if (!silent) 801 befs_error(sb, "cannot parse mount options"); 802 goto unacquire_priv_sbp; 803 } 804 805 befs_debug(sb, "---> %s", __func__); 806 807 if (!(sb->s_flags & MS_RDONLY)) { 808 befs_warning(sb, 809 "No write support. Marking filesystem read-only"); 810 sb->s_flags |= MS_RDONLY; 811 } 812 813 /* 814 * Set dummy blocksize to read super block. 815 * Will be set to real fs blocksize later. 816 * 817 * Linux 2.4.10 and later refuse to read blocks smaller than 818 * the logical block size for the device. But we also need to read at 819 * least 1k to get the second 512 bytes of the volume. 820 */ 821 blocksize = sb_min_blocksize(sb, 1024); 822 if (!blocksize) { 823 if (!silent) 824 befs_error(sb, "unable to set blocksize"); 825 goto unacquire_priv_sbp; 826 } 827 828 bh = sb_bread(sb, sb_block); 829 if (!bh) { 830 if (!silent) 831 befs_error(sb, "unable to read superblock"); 832 goto unacquire_priv_sbp; 833 } 834 835 /* account for offset of super block on x86 */ 836 disk_sb = (befs_super_block *) bh->b_data; 837 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) || 838 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) { 839 befs_debug(sb, "Using PPC superblock location"); 840 } else { 841 befs_debug(sb, "Using x86 superblock location"); 842 disk_sb = 843 (befs_super_block *) ((void *) bh->b_data + x86_sb_off); 844 } 845 846 if ((befs_load_sb(sb, disk_sb) != BEFS_OK) || 847 (befs_check_sb(sb) != BEFS_OK)) 848 goto unacquire_bh; 849 850 befs_dump_super_block(sb, disk_sb); 851 852 brelse(bh); 853 854 if (befs_sb->num_blocks > ~((sector_t)0)) { 855 if (!silent) 856 befs_error(sb, "blocks count: %llu is larger than the host can use", 857 befs_sb->num_blocks); 858 goto unacquire_priv_sbp; 859 } 860 861 /* 862 * set up enough so that it can read an inode 863 * Fill in kernel superblock fields from private sb 864 */ 865 sb->s_magic = BEFS_SUPER_MAGIC; 866 /* Set real blocksize of fs */ 867 sb_set_blocksize(sb, (ulong) befs_sb->block_size); 868 sb->s_op = &befs_sops; 869 sb->s_export_op = &befs_export_operations; 870 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir))); 871 if (IS_ERR(root)) { 872 ret = PTR_ERR(root); 873 goto unacquire_priv_sbp; 874 } 875 sb->s_root = d_make_root(root); 876 if (!sb->s_root) { 877 if (!silent) 878 befs_error(sb, "get root inode failed"); 879 goto unacquire_priv_sbp; 880 } 881 882 /* load nls library */ 883 if (befs_sb->mount_opts.iocharset) { 884 befs_debug(sb, "Loading nls: %s", 885 befs_sb->mount_opts.iocharset); 886 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset); 887 if (!befs_sb->nls) { 888 befs_warning(sb, "Cannot load nls %s" 889 " loading default nls", 890 befs_sb->mount_opts.iocharset); 891 befs_sb->nls = load_nls_default(); 892 } 893 /* load default nls if none is specified in mount options */ 894 } else { 895 befs_debug(sb, "Loading default nls"); 896 befs_sb->nls = load_nls_default(); 897 } 898 899 return 0; 900 901 unacquire_bh: 902 brelse(bh); 903 904 unacquire_priv_sbp: 905 kfree(befs_sb->mount_opts.iocharset); 906 kfree(sb->s_fs_info); 907 sb->s_fs_info = NULL; 908 909 unacquire_none: 910 return ret; 911 } 912 913 static int 914 befs_remount(struct super_block *sb, int *flags, char *data) 915 { 916 sync_filesystem(sb); 917 if (!(*flags & MS_RDONLY)) 918 return -EINVAL; 919 return 0; 920 } 921 922 static int 923 befs_statfs(struct dentry *dentry, struct kstatfs *buf) 924 { 925 struct super_block *sb = dentry->d_sb; 926 u64 id = huge_encode_dev(sb->s_bdev->bd_dev); 927 928 befs_debug(sb, "---> %s", __func__); 929 930 buf->f_type = BEFS_SUPER_MAGIC; 931 buf->f_bsize = sb->s_blocksize; 932 buf->f_blocks = BEFS_SB(sb)->num_blocks; 933 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks; 934 buf->f_bavail = buf->f_bfree; 935 buf->f_files = 0; /* UNKNOWN */ 936 buf->f_ffree = 0; /* UNKNOWN */ 937 buf->f_fsid.val[0] = (u32)id; 938 buf->f_fsid.val[1] = (u32)(id >> 32); 939 buf->f_namelen = BEFS_NAME_LEN; 940 941 befs_debug(sb, "<--- %s", __func__); 942 943 return 0; 944 } 945 946 static struct dentry * 947 befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, 948 void *data) 949 { 950 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super); 951 } 952 953 static struct file_system_type befs_fs_type = { 954 .owner = THIS_MODULE, 955 .name = "befs", 956 .mount = befs_mount, 957 .kill_sb = kill_block_super, 958 .fs_flags = FS_REQUIRES_DEV, 959 }; 960 MODULE_ALIAS_FS("befs"); 961 962 static int __init 963 init_befs_fs(void) 964 { 965 int err; 966 967 pr_info("version: %s\n", BEFS_VERSION); 968 969 err = befs_init_inodecache(); 970 if (err) 971 goto unacquire_none; 972 973 err = register_filesystem(&befs_fs_type); 974 if (err) 975 goto unacquire_inodecache; 976 977 return 0; 978 979 unacquire_inodecache: 980 befs_destroy_inodecache(); 981 982 unacquire_none: 983 return err; 984 } 985 986 static void __exit 987 exit_befs_fs(void) 988 { 989 befs_destroy_inodecache(); 990 991 unregister_filesystem(&befs_fs_type); 992 } 993 994 /* 995 * Macros that typecheck the init and exit functions, 996 * ensures that they are called at init and cleanup, 997 * and eliminates warnings about unused functions. 998 */ 999 module_init(init_befs_fs) 1000 module_exit(exit_befs_fs) 1001