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