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v6.2
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * linux/fs/befs/linuxvfs.c
   4 *
   5 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
   6 *
   7 */
   8
   9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
  11#include <linux/module.h>
  12#include <linux/slab.h>
  13#include <linux/fs.h>
  14#include <linux/errno.h>
  15#include <linux/stat.h>
  16#include <linux/nls.h>
  17#include <linux/buffer_head.h>
  18#include <linux/vfs.h>
  19#include <linux/parser.h>
  20#include <linux/namei.h>
  21#include <linux/sched.h>
  22#include <linux/cred.h>
  23#include <linux/exportfs.h>
  24#include <linux/seq_file.h>
  25#include <linux/blkdev.h>
  26
  27#include "befs.h"
  28#include "btree.h"
  29#include "inode.h"
  30#include "datastream.h"
  31#include "super.h"
  32#include "io.h"
  33
  34MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
  35MODULE_AUTHOR("Will Dyson");
  36MODULE_LICENSE("GPL");
  37
  38/* The units the vfs expects inode->i_blocks to be in */
  39#define VFS_BLOCK_SIZE 512
  40
  41static int befs_readdir(struct file *, struct dir_context *);
  42static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
  43static int befs_read_folio(struct file *file, struct folio *folio);
  44static sector_t befs_bmap(struct address_space *mapping, sector_t block);
  45static struct dentry *befs_lookup(struct inode *, struct dentry *,
  46				  unsigned int);
  47static struct inode *befs_iget(struct super_block *, unsigned long);
  48static struct inode *befs_alloc_inode(struct super_block *sb);
  49static void befs_free_inode(struct inode *inode);
  50static void befs_destroy_inodecache(void);
  51static int befs_symlink_read_folio(struct file *, struct folio *);
 
  52static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
  53			char **out, int *out_len);
  54static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
  55			char **out, int *out_len);
  56static void befs_put_super(struct super_block *);
  57static int befs_remount(struct super_block *, int *, char *);
  58static int befs_statfs(struct dentry *, struct kstatfs *);
  59static int befs_show_options(struct seq_file *, struct dentry *);
  60static int parse_options(char *, struct befs_mount_options *);
  61static struct dentry *befs_fh_to_dentry(struct super_block *sb,
  62				struct fid *fid, int fh_len, int fh_type);
  63static struct dentry *befs_fh_to_parent(struct super_block *sb,
  64				struct fid *fid, int fh_len, int fh_type);
  65static struct dentry *befs_get_parent(struct dentry *child);
  66
  67static const struct super_operations befs_sops = {
  68	.alloc_inode	= befs_alloc_inode,	/* allocate a new inode */
  69	.free_inode	= befs_free_inode, /* deallocate an inode */
  70	.put_super	= befs_put_super,	/* uninit super */
  71	.statfs		= befs_statfs,	/* statfs */
  72	.remount_fs	= befs_remount,
  73	.show_options	= befs_show_options,
  74};
  75
  76/* slab cache for befs_inode_info objects */
  77static struct kmem_cache *befs_inode_cachep;
  78
  79static const struct file_operations befs_dir_operations = {
  80	.read		= generic_read_dir,
  81	.iterate_shared	= befs_readdir,
  82	.llseek		= generic_file_llseek,
  83};
  84
  85static const struct inode_operations befs_dir_inode_operations = {
  86	.lookup		= befs_lookup,
  87};
  88
  89static const struct address_space_operations befs_aops = {
  90	.read_folio	= befs_read_folio,
  91	.bmap		= befs_bmap,
  92};
  93
  94static const struct address_space_operations befs_symlink_aops = {
  95	.read_folio	= befs_symlink_read_folio,
 
  96};
  97
  98static const struct export_operations befs_export_operations = {
  99	.fh_to_dentry	= befs_fh_to_dentry,
 100	.fh_to_parent	= befs_fh_to_parent,
 101	.get_parent	= befs_get_parent,
 102};
 103
 104/*
 105 * Called by generic_file_read() to read a folio of data
 106 *
 107 * In turn, simply calls a generic block read function and
 108 * passes it the address of befs_get_block, for mapping file
 109 * positions to disk blocks.
 110 */
 111static int befs_read_folio(struct file *file, struct folio *folio)
 
 112{
 113	return block_read_full_folio(folio, befs_get_block);
 114}
 115
 116static sector_t
 117befs_bmap(struct address_space *mapping, sector_t block)
 118{
 119	return generic_block_bmap(mapping, block, befs_get_block);
 120}
 121
 122/*
 123 * Generic function to map a file position (block) to a
 124 * disk offset (passed back in bh_result).
 125 *
 126 * Used by many higher level functions.
 127 *
 128 * Calls befs_fblock2brun() in datastream.c to do the real work.
 
 
 129 */
 130
 131static int
 132befs_get_block(struct inode *inode, sector_t block,
 133	       struct buffer_head *bh_result, int create)
 134{
 135	struct super_block *sb = inode->i_sb;
 136	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
 137	befs_block_run run = BAD_IADDR;
 138	int res;
 139	ulong disk_off;
 140
 141	befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
 142		   (unsigned long)inode->i_ino, (long)block);
 
 
 
 
 
 
 
 
 143	if (create) {
 144		befs_error(sb, "befs_get_block() was asked to write to "
 145			   "block %ld in inode %lu", (long)block,
 146			   (unsigned long)inode->i_ino);
 147		return -EPERM;
 148	}
 149
 150	res = befs_fblock2brun(sb, ds, block, &run);
 151	if (res != BEFS_OK) {
 152		befs_error(sb,
 153			   "<--- %s for inode %lu, block %ld ERROR",
 154			   __func__, (unsigned long)inode->i_ino,
 155			   (long)block);
 156		return -EFBIG;
 157	}
 158
 159	disk_off = (ulong) iaddr2blockno(sb, &run);
 160
 161	map_bh(bh_result, inode->i_sb, disk_off);
 162
 163	befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu",
 164		  __func__, (unsigned long)inode->i_ino, (long)block,
 165		  (unsigned long)disk_off);
 166
 167	return 0;
 168}
 169
 170static struct dentry *
 171befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 172{
 173	struct inode *inode;
 174	struct super_block *sb = dir->i_sb;
 175	const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
 176	befs_off_t offset;
 177	int ret;
 178	int utfnamelen;
 179	char *utfname;
 180	const char *name = dentry->d_name.name;
 181
 182	befs_debug(sb, "---> %s name %pd inode %ld", __func__,
 183		   dentry, dir->i_ino);
 184
 185	/* Convert to UTF-8 */
 186	if (BEFS_SB(sb)->nls) {
 187		ret =
 188		    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
 189		if (ret < 0) {
 190			befs_debug(sb, "<--- %s ERROR", __func__);
 191			return ERR_PTR(ret);
 192		}
 193		ret = befs_btree_find(sb, ds, utfname, &offset);
 194		kfree(utfname);
 195
 196	} else {
 197		ret = befs_btree_find(sb, ds, name, &offset);
 198	}
 199
 200	if (ret == BEFS_BT_NOT_FOUND) {
 201		befs_debug(sb, "<--- %s %pd not found", __func__, dentry);
 202		inode = NULL;
 
 
 203	} else if (ret != BEFS_OK || offset == 0) {
 204		befs_error(sb, "<--- %s Error", __func__);
 205		inode = ERR_PTR(-ENODATA);
 206	} else {
 207		inode = befs_iget(dir->i_sb, (ino_t) offset);
 208	}
 
 
 
 
 
 
 
 209	befs_debug(sb, "<--- %s", __func__);
 210
 211	return d_splice_alias(inode, dentry);
 212}
 213
 214static int
 215befs_readdir(struct file *file, struct dir_context *ctx)
 216{
 217	struct inode *inode = file_inode(file);
 218	struct super_block *sb = inode->i_sb;
 219	const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
 220	befs_off_t value;
 221	int result;
 222	size_t keysize;
 
 223	char keybuf[BEFS_NAME_LEN + 1];
 
 224
 225	befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld",
 226		  __func__, file, inode->i_ino, ctx->pos);
 227
 228	while (1) {
 229		result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,
 230					 keybuf, &keysize, &value);
 231
 232		if (result == BEFS_ERR) {
 233			befs_debug(sb, "<--- %s ERROR", __func__);
 234			befs_error(sb, "IO error reading %pD (inode %lu)",
 235				   file, inode->i_ino);
 236			return -EIO;
 237
 238		} else if (result == BEFS_BT_END) {
 239			befs_debug(sb, "<--- %s END", __func__);
 240			return 0;
 241
 242		} else if (result == BEFS_BT_EMPTY) {
 243			befs_debug(sb, "<--- %s Empty directory", __func__);
 244			return 0;
 245		}
 246
 247		/* Convert to NLS */
 248		if (BEFS_SB(sb)->nls) {
 249			char *nlsname;
 250			int nlsnamelen;
 251
 252			result =
 253			    befs_utf2nls(sb, keybuf, keysize, &nlsname,
 254					 &nlsnamelen);
 255			if (result < 0) {
 256				befs_debug(sb, "<--- %s ERROR", __func__);
 257				return result;
 258			}
 259			if (!dir_emit(ctx, nlsname, nlsnamelen,
 260				      (ino_t) value, DT_UNKNOWN)) {
 261				kfree(nlsname);
 262				return 0;
 263			}
 264			kfree(nlsname);
 265		} else {
 266			if (!dir_emit(ctx, keybuf, keysize,
 267				      (ino_t) value, DT_UNKNOWN))
 268				return 0;
 269		}
 270		ctx->pos++;
 
 
 
 
 271	}
 
 
 
 
 
 
 272}
 273
 274static struct inode *
 275befs_alloc_inode(struct super_block *sb)
 276{
 277	struct befs_inode_info *bi;
 
 
 
 
 
 
 278
 279	bi = alloc_inode_sb(sb, befs_inode_cachep, GFP_KERNEL);
 280	if (!bi)
 281		return NULL;
 282	return &bi->vfs_inode;
 283}
 284
 285static void befs_free_inode(struct inode *inode)
 286{
 287	kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
 288}
 289
 290static 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
 297static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
 298{
 299	struct buffer_head *bh;
 300	befs_inode *raw_inode;
 301	struct befs_sb_info *befs_sb = BEFS_SB(sb);
 302	struct befs_inode_info *befs_ino;
 
 303	struct inode *inode;
 
 304
 305	befs_debug(sb, "---> %s inode = %lu", __func__, ino);
 306
 307	inode = iget_locked(sb, ino);
 308	if (!inode)
 309		return ERR_PTR(-ENOMEM);
 310	if (!(inode->i_state & I_NEW))
 311		return inode;
 312
 313	befs_ino = BEFS_I(inode);
 314
 315	/* convert from vfs's inode number to befs's inode number */
 316	befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
 317
 318	befs_debug(sb, "  real inode number [%u, %hu, %hu]",
 319		   befs_ino->i_inode_num.allocation_group,
 320		   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
 321
 322	bh = sb_bread(sb, inode->i_ino);
 323	if (!bh) {
 324		befs_error(sb, "unable to read inode block - "
 325			   "inode = %lu", inode->i_ino);
 326		goto unacquire_none;
 327	}
 328
 329	raw_inode = (befs_inode *) bh->b_data;
 330
 331	befs_dump_inode(sb, raw_inode);
 332
 333	if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
 334		befs_error(sb, "Bad inode: %lu", inode->i_ino);
 335		goto unacquire_bh;
 336	}
 337
 338	inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
 339
 340	/*
 341	 * set uid and gid.  But since current BeOS is single user OS, so
 342	 * you can change by "uid" or "gid" options.
 343	 */
 344
 345	inode->i_uid = befs_sb->mount_opts.use_uid ?
 346		befs_sb->mount_opts.uid :
 347		make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
 348	inode->i_gid = befs_sb->mount_opts.use_gid ?
 349		befs_sb->mount_opts.gid :
 350		make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
 351
 352	set_nlink(inode, 1);
 353
 354	/*
 355	 * BEFS's time is 64 bits, but current VFS is 32 bits...
 356	 * BEFS don't have access time. Nor inode change time. VFS
 357	 * doesn't have creation time.
 358	 * Also, the lower 16 bits of the last_modified_time and
 359	 * create_time are just a counter to help ensure uniqueness
 360	 * for indexing purposes. (PFD, page 54)
 361	 */
 362
 363	inode->i_mtime.tv_sec =
 364	    fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
 365	inode->i_mtime.tv_nsec = 0;   /* lower 16 bits are not a time */
 366	inode->i_ctime = inode->i_mtime;
 367	inode->i_atime = inode->i_mtime;
 368
 369	befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
 370	befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
 371	befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
 372	befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
 373
 374	if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
 375		inode->i_size = 0;
 376		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
 377		strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
 378			BEFS_SYMLINK_LEN);
 
 379	} else {
 380		int num_blks;
 381
 382		befs_ino->i_data.ds =
 383		    fsds_to_cpu(sb, &raw_inode->data.datastream);
 384
 385		num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
 386		inode->i_blocks =
 387		    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
 388		inode->i_size = befs_ino->i_data.ds.size;
 389	}
 390
 391	inode->i_mapping->a_ops = &befs_aops;
 392
 393	if (S_ISREG(inode->i_mode)) {
 394		inode->i_fop = &generic_ro_fops;
 395	} else if (S_ISDIR(inode->i_mode)) {
 396		inode->i_op = &befs_dir_inode_operations;
 397		inode->i_fop = &befs_dir_operations;
 398	} else if (S_ISLNK(inode->i_mode)) {
 399		if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
 400			inode->i_op = &page_symlink_inode_operations;
 401			inode_nohighmem(inode);
 402			inode->i_mapping->a_ops = &befs_symlink_aops;
 403		} else {
 404			inode->i_link = befs_ino->i_data.symlink;
 405			inode->i_op = &simple_symlink_inode_operations;
 406		}
 407	} else {
 408		befs_error(sb, "Inode %lu is not a regular file, "
 409			   "directory or symlink. THAT IS WRONG! BeFS has no "
 410			   "on disk special files", inode->i_ino);
 411		goto unacquire_bh;
 412	}
 413
 414	brelse(bh);
 415	befs_debug(sb, "<--- %s", __func__);
 416	unlock_new_inode(inode);
 417	return inode;
 418
 419unacquire_bh:
 420	brelse(bh);
 421
 422unacquire_none:
 423	iget_failed(inode);
 424	befs_debug(sb, "<--- %s - Bad inode", __func__);
 425	return ERR_PTR(-EIO);
 426}
 427
 428/* Initialize the inode cache. Called at fs setup.
 429 *
 430 * Taken from NFS implementation by Al Viro.
 431 */
 432static int __init
 433befs_init_inodecache(void)
 434{
 435	befs_inode_cachep = kmem_cache_create_usercopy("befs_inode_cache",
 436				sizeof(struct befs_inode_info), 0,
 437				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
 438					SLAB_ACCOUNT),
 439				offsetof(struct befs_inode_info,
 440					i_data.symlink),
 441				sizeof_field(struct befs_inode_info,
 442					i_data.symlink),
 443				init_once);
 444	if (befs_inode_cachep == NULL)
 445		return -ENOMEM;
 446
 447	return 0;
 448}
 449
 450/* Called at fs teardown.
 451 *
 452 * Taken from NFS implementation by Al Viro.
 453 */
 454static void
 455befs_destroy_inodecache(void)
 456{
 457	/*
 458	 * Make sure all delayed rcu free inodes are flushed before we
 459	 * destroy cache.
 460	 */
 461	rcu_barrier();
 462	kmem_cache_destroy(befs_inode_cachep);
 463}
 464
 465/*
 466 * The inode of symbolic link is different to data stream.
 467 * The data stream become link name. Unless the LONG_SYMLINK
 468 * flag is set.
 469 */
 470static int befs_symlink_read_folio(struct file *unused, struct folio *folio)
 
 471{
 472	struct inode *inode = folio->mapping->host;
 473	struct super_block *sb = inode->i_sb;
 474	struct befs_inode_info *befs_ino = BEFS_I(inode);
 475	befs_data_stream *data = &befs_ino->i_data.ds;
 476	befs_off_t len = data->size;
 477	char *link = folio_address(folio);
 478
 479	if (len == 0 || len > PAGE_SIZE) {
 480		befs_error(sb, "Long symlink with illegal length");
 481		goto fail;
 482	}
 483	befs_debug(sb, "Follow long symlink");
 484
 485	if (befs_read_lsymlink(sb, data, link, len) != len) {
 486		befs_error(sb, "Failed to read entire long symlink");
 487		goto fail;
 
 
 
 
 
 
 
 488	}
 489	link[len - 1] = '\0';
 490	folio_mark_uptodate(folio);
 491	folio_unlock(folio);
 492	return 0;
 493fail:
 494	folio_set_error(folio);
 495	folio_unlock(folio);
 496	return -EIO;
 
 
 
 497}
 498
 499/*
 500 * UTF-8 to NLS charset convert routine
 
 501 *
 502 * Uses uni2char() / char2uni() rather than the nls tables directly
 
 503 */
 
 504static int
 505befs_utf2nls(struct super_block *sb, const char *in,
 506	     int in_len, char **out, int *out_len)
 507{
 508	struct nls_table *nls = BEFS_SB(sb)->nls;
 509	int i, o;
 510	unicode_t uni;
 511	int unilen, utflen;
 512	char *result;
 513	/* The utf8->nls conversion won't make the final nls string bigger
 514	 * than the utf one, but if the string is pure ascii they'll have the
 515	 * same width and an extra char is needed to save the additional \0
 516	 */
 517	int maxlen = in_len + 1;
 518
 519	befs_debug(sb, "---> %s", __func__);
 520
 521	if (!nls) {
 522		befs_error(sb, "%s called with no NLS table loaded", __func__);
 523		return -EINVAL;
 524	}
 525
 526	*out = result = kmalloc(maxlen, GFP_NOFS);
 527	if (!*out)
 
 
 528		return -ENOMEM;
 
 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
 551conv_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
 581static int
 582befs_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	/*
 591	 * There are nls characters that will translate to 3-chars-wide UTF-8
 592	 * characters, an additional byte is needed to save the final \0
 593	 * in special cases
 594	 */
 595	int maxlen = (3 * in_len) + 1;
 596
 597	befs_debug(sb, "---> %s\n", __func__);
 598
 599	if (!nls) {
 600		befs_error(sb, "%s called with no NLS table loaded.",
 601			   __func__);
 602		return -EINVAL;
 603	}
 604
 605	*out = result = kmalloc(maxlen, GFP_NOFS);
 606	if (!*out) {
 
 607		*out_len = 0;
 608		return -ENOMEM;
 609	}
 610
 611	for (i = o = 0; i < in_len; i += unilen, o += utflen) {
 612
 613		/* convert from nls to unicode */
 614		unilen = nls->char2uni(&in[i], in_len - i, &uni);
 615		if (unilen < 0)
 616			goto conv_err;
 617
 618		/* convert from unicode to UTF-8 */
 619		utflen = utf32_to_utf8(uni, &result[o], 3);
 620		if (utflen <= 0)
 621			goto conv_err;
 622	}
 623
 624	result[o] = '\0';
 625	*out_len = o;
 626
 627	befs_debug(sb, "<--- %s", __func__);
 628
 629	return i;
 630
 631conv_err:
 632	befs_error(sb, "Name using character set %s contains a character that "
 633		   "cannot be converted to unicode.", nls->charset);
 634	befs_debug(sb, "<--- %s", __func__);
 635	kfree(result);
 636	return -EILSEQ;
 637}
 638
 639static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino,
 640					 uint32_t generation)
 641{
 642	/* No need to handle i_generation */
 643	return befs_iget(sb, ino);
 644}
 645
 646/*
 647 * Map a NFS file handle to a corresponding dentry
 648 */
 649static struct dentry *befs_fh_to_dentry(struct super_block *sb,
 650				struct fid *fid, int fh_len, int fh_type)
 651{
 652	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 653				    befs_nfs_get_inode);
 654}
 655
 656/*
 657 * Find the parent for a file specified by NFS handle
 658 */
 659static struct dentry *befs_fh_to_parent(struct super_block *sb,
 660				struct fid *fid, int fh_len, int fh_type)
 661{
 662	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 663				    befs_nfs_get_inode);
 664}
 665
 666static struct dentry *befs_get_parent(struct dentry *child)
 667{
 668	struct inode *parent;
 669	struct befs_inode_info *befs_ino = BEFS_I(d_inode(child));
 670
 671	parent = befs_iget(child->d_sb,
 672			   (unsigned long)befs_ino->i_parent.start);
 673	if (IS_ERR(parent))
 674		return ERR_CAST(parent);
 675
 676	return d_obtain_alias(parent);
 677}
 678
 679enum {
 680	Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
 681};
 682
 683static const match_table_t befs_tokens = {
 684	{Opt_uid, "uid=%d"},
 685	{Opt_gid, "gid=%d"},
 686	{Opt_charset, "iocharset=%s"},
 687	{Opt_debug, "debug"},
 688	{Opt_err, NULL}
 689};
 690
 691static int
 692parse_options(char *options, struct befs_mount_options *opts)
 693{
 694	char *p;
 695	substring_t args[MAX_OPT_ARGS];
 696	int option;
 697	kuid_t uid;
 698	kgid_t gid;
 699
 700	/* Initialize options */
 701	opts->uid = GLOBAL_ROOT_UID;
 702	opts->gid = GLOBAL_ROOT_GID;
 703	opts->use_uid = 0;
 704	opts->use_gid = 0;
 705	opts->iocharset = NULL;
 706	opts->debug = 0;
 707
 708	if (!options)
 709		return 1;
 710
 711	while ((p = strsep(&options, ",")) != NULL) {
 712		int token;
 713
 714		if (!*p)
 715			continue;
 716
 717		token = match_token(p, befs_tokens, args);
 718		switch (token) {
 719		case Opt_uid:
 720			if (match_int(&args[0], &option))
 721				return 0;
 722			uid = INVALID_UID;
 723			if (option >= 0)
 724				uid = make_kuid(current_user_ns(), option);
 725			if (!uid_valid(uid)) {
 726				pr_err("Invalid uid %d, "
 727				       "using default\n", option);
 728				break;
 729			}
 730			opts->uid = uid;
 731			opts->use_uid = 1;
 732			break;
 733		case Opt_gid:
 734			if (match_int(&args[0], &option))
 735				return 0;
 736			gid = INVALID_GID;
 737			if (option >= 0)
 738				gid = make_kgid(current_user_ns(), option);
 739			if (!gid_valid(gid)) {
 740				pr_err("Invalid gid %d, "
 741				       "using default\n", option);
 742				break;
 743			}
 744			opts->gid = gid;
 745			opts->use_gid = 1;
 746			break;
 747		case Opt_charset:
 748			kfree(opts->iocharset);
 749			opts->iocharset = match_strdup(&args[0]);
 750			if (!opts->iocharset) {
 751				pr_err("allocation failure for "
 752				       "iocharset string\n");
 753				return 0;
 754			}
 755			break;
 756		case Opt_debug:
 757			opts->debug = 1;
 758			break;
 759		default:
 760			pr_err("Unrecognized mount option \"%s\" "
 761			       "or missing value\n", p);
 762			return 0;
 763		}
 764	}
 765	return 1;
 766}
 767
 768static int befs_show_options(struct seq_file *m, struct dentry *root)
 769{
 770	struct befs_sb_info *befs_sb = BEFS_SB(root->d_sb);
 771	struct befs_mount_options *opts = &befs_sb->mount_opts;
 772
 773	if (!uid_eq(opts->uid, GLOBAL_ROOT_UID))
 774		seq_printf(m, ",uid=%u",
 775			   from_kuid_munged(&init_user_ns, opts->uid));
 776	if (!gid_eq(opts->gid, GLOBAL_ROOT_GID))
 777		seq_printf(m, ",gid=%u",
 778			   from_kgid_munged(&init_user_ns, opts->gid));
 779	if (opts->iocharset)
 780		seq_printf(m, ",charset=%s", opts->iocharset);
 781	if (opts->debug)
 782		seq_puts(m, ",debug");
 783	return 0;
 784}
 785
 786/* This function has the responsibiltiy of getting the
 787 * filesystem ready for unmounting.
 788 * Basically, we free everything that we allocated in
 789 * befs_read_inode
 790 */
 791static void
 792befs_put_super(struct super_block *sb)
 793{
 794	kfree(BEFS_SB(sb)->mount_opts.iocharset);
 795	BEFS_SB(sb)->mount_opts.iocharset = NULL;
 796	unload_nls(BEFS_SB(sb)->nls);
 797	kfree(sb->s_fs_info);
 798	sb->s_fs_info = NULL;
 799}
 800
 801/* Allocate private field of the superblock, fill it.
 802 *
 803 * Finish filling the public superblock fields
 804 * Make the root directory
 805 * Load a set of NLS translations if needed.
 806 */
 807static int
 808befs_fill_super(struct super_block *sb, void *data, int silent)
 809{
 810	struct buffer_head *bh;
 811	struct befs_sb_info *befs_sb;
 812	befs_super_block *disk_sb;
 813	struct inode *root;
 814	long ret = -EINVAL;
 815	const unsigned long sb_block = 0;
 816	const off_t x86_sb_off = 512;
 817	int blocksize;
 
 818
 819	sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);
 820	if (sb->s_fs_info == NULL)
 
 
 821		goto unacquire_none;
 822
 823	befs_sb = BEFS_SB(sb);
 824
 825	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
 826		if (!silent)
 827			befs_error(sb, "cannot parse mount options");
 828		goto unacquire_priv_sbp;
 829	}
 830
 831	befs_debug(sb, "---> %s", __func__);
 832
 833	if (!sb_rdonly(sb)) {
 
 834		befs_warning(sb,
 835			     "No write support. Marking filesystem read-only");
 836		sb->s_flags |= SB_RDONLY;
 837	}
 
 838
 839	/*
 840	 * Set dummy blocksize to read super block.
 841	 * Will be set to real fs blocksize later.
 842	 *
 843	 * Linux 2.4.10 and later refuse to read blocks smaller than
 844	 * the logical block size for the device. But we also need to read at
 845	 * least 1k to get the second 512 bytes of the volume.
 846	 */
 847	blocksize = sb_min_blocksize(sb, 1024);
 848	if (!blocksize) {
 849		if (!silent)
 850			befs_error(sb, "unable to set blocksize");
 851		goto unacquire_priv_sbp;
 852	}
 853
 854	bh = sb_bread(sb, sb_block);
 855	if (!bh) {
 856		if (!silent)
 857			befs_error(sb, "unable to read superblock");
 858		goto unacquire_priv_sbp;
 859	}
 860
 861	/* account for offset of super block on x86 */
 862	disk_sb = (befs_super_block *) bh->b_data;
 863	if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
 864	    (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
 865		befs_debug(sb, "Using PPC superblock location");
 866	} else {
 867		befs_debug(sb, "Using x86 superblock location");
 868		disk_sb =
 869		    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
 870	}
 871
 872	if ((befs_load_sb(sb, disk_sb) != BEFS_OK) ||
 873	    (befs_check_sb(sb) != BEFS_OK))
 874		goto unacquire_bh;
 875
 876	befs_dump_super_block(sb, disk_sb);
 877
 878	brelse(bh);
 879
 880	if (befs_sb->num_blocks > ~((sector_t)0)) {
 881		if (!silent)
 882			befs_error(sb, "blocks count: %llu is larger than the host can use",
 883					befs_sb->num_blocks);
 
 
 
 884		goto unacquire_priv_sbp;
 885	}
 886
 887	/*
 888	 * set up enough so that it can read an inode
 889	 * Fill in kernel superblock fields from private sb
 890	 */
 891	sb->s_magic = BEFS_SUPER_MAGIC;
 892	/* Set real blocksize of fs */
 893	sb_set_blocksize(sb, (ulong) befs_sb->block_size);
 894	sb->s_op = &befs_sops;
 895	sb->s_export_op = &befs_export_operations;
 896	sb->s_time_min = 0;
 897	sb->s_time_max = 0xffffffffffffll;
 898	root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
 899	if (IS_ERR(root)) {
 900		ret = PTR_ERR(root);
 901		goto unacquire_priv_sbp;
 902	}
 903	sb->s_root = d_make_root(root);
 904	if (!sb->s_root) {
 905		if (!silent)
 906			befs_error(sb, "get root inode failed");
 907		goto unacquire_priv_sbp;
 908	}
 909
 910	/* load nls library */
 911	if (befs_sb->mount_opts.iocharset) {
 912		befs_debug(sb, "Loading nls: %s",
 913			   befs_sb->mount_opts.iocharset);
 914		befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
 915		if (!befs_sb->nls) {
 916			befs_warning(sb, "Cannot load nls %s"
 917					" loading default nls",
 918					befs_sb->mount_opts.iocharset);
 919			befs_sb->nls = load_nls_default();
 920		}
 921	/* load default nls if none is specified  in mount options */
 922	} else {
 923		befs_debug(sb, "Loading default nls");
 924		befs_sb->nls = load_nls_default();
 925	}
 926
 927	return 0;
 928
 929unacquire_bh:
 930	brelse(bh);
 931
 932unacquire_priv_sbp:
 933	kfree(befs_sb->mount_opts.iocharset);
 934	kfree(sb->s_fs_info);
 935	sb->s_fs_info = NULL;
 936
 937unacquire_none:
 
 938	return ret;
 939}
 940
 941static int
 942befs_remount(struct super_block *sb, int *flags, char *data)
 943{
 944	sync_filesystem(sb);
 945	if (!(*flags & SB_RDONLY))
 946		return -EINVAL;
 947	return 0;
 948}
 949
 950static int
 951befs_statfs(struct dentry *dentry, struct kstatfs *buf)
 952{
 953	struct super_block *sb = dentry->d_sb;
 954	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 955
 956	befs_debug(sb, "---> %s", __func__);
 957
 958	buf->f_type = BEFS_SUPER_MAGIC;
 959	buf->f_bsize = sb->s_blocksize;
 960	buf->f_blocks = BEFS_SB(sb)->num_blocks;
 961	buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
 962	buf->f_bavail = buf->f_bfree;
 963	buf->f_files = 0;	/* UNKNOWN */
 964	buf->f_ffree = 0;	/* UNKNOWN */
 965	buf->f_fsid = u64_to_fsid(id);
 
 966	buf->f_namelen = BEFS_NAME_LEN;
 967
 968	befs_debug(sb, "<--- %s", __func__);
 969
 970	return 0;
 971}
 972
 973static struct dentry *
 974befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
 975	    void *data)
 976{
 977	return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
 978}
 979
 980static struct file_system_type befs_fs_type = {
 981	.owner		= THIS_MODULE,
 982	.name		= "befs",
 983	.mount		= befs_mount,
 984	.kill_sb	= kill_block_super,
 985	.fs_flags	= FS_REQUIRES_DEV,
 986};
 987MODULE_ALIAS_FS("befs");
 988
 989static int __init
 990init_befs_fs(void)
 991{
 992	int err;
 993
 994	pr_info("version: %s\n", BEFS_VERSION);
 995
 996	err = befs_init_inodecache();
 997	if (err)
 998		goto unacquire_none;
 999
1000	err = register_filesystem(&befs_fs_type);
1001	if (err)
1002		goto unacquire_inodecache;
1003
1004	return 0;
1005
1006unacquire_inodecache:
1007	befs_destroy_inodecache();
1008
1009unacquire_none:
1010	return err;
1011}
1012
1013static void __exit
1014exit_befs_fs(void)
1015{
1016	befs_destroy_inodecache();
1017
1018	unregister_filesystem(&befs_fs_type);
1019}
1020
1021/*
1022 * Macros that typecheck the init and exit functions,
1023 * ensures that they are called at init and cleanup,
1024 * and eliminates warnings about unused functions.
1025 */
1026module_init(init_befs_fs)
1027module_exit(exit_befs_fs)
v3.15
 
   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
  29MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
  30MODULE_AUTHOR("Will Dyson");
  31MODULE_LICENSE("GPL");
  32
  33/* The units the vfs expects inode->i_blocks to be in */
  34#define VFS_BLOCK_SIZE 512
  35
  36static int befs_readdir(struct file *, struct dir_context *);
  37static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
  38static int befs_readpage(struct file *file, struct page *page);
  39static sector_t befs_bmap(struct address_space *mapping, sector_t block);
  40static struct dentry *befs_lookup(struct inode *, struct dentry *, unsigned int);
 
  41static struct inode *befs_iget(struct super_block *, unsigned long);
  42static struct inode *befs_alloc_inode(struct super_block *sb);
  43static void befs_destroy_inode(struct inode *inode);
  44static void befs_destroy_inodecache(void);
  45static void *befs_follow_link(struct dentry *, struct nameidata *);
  46static void *befs_fast_follow_link(struct dentry *, struct nameidata *);
  47static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
  48			char **out, int *out_len);
  49static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
  50			char **out, int *out_len);
  51static void befs_put_super(struct super_block *);
  52static int befs_remount(struct super_block *, int *, char *);
  53static int befs_statfs(struct dentry *, struct kstatfs *);
  54static int parse_options(char *, befs_mount_options *);
 
 
 
 
 
 
  55
  56static 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 */
  66static struct kmem_cache *befs_inode_cachep;
  67
  68static const struct file_operations befs_dir_operations = {
  69	.read		= generic_read_dir,
  70	.iterate	= befs_readdir,
  71	.llseek		= generic_file_llseek,
  72};
  73
  74static const struct inode_operations befs_dir_inode_operations = {
  75	.lookup		= befs_lookup,
  76};
  77
  78static const struct address_space_operations befs_aops = {
  79	.readpage	= befs_readpage,
  80	.bmap		= befs_bmap,
  81};
  82
  83static const struct inode_operations befs_fast_symlink_inode_operations = {
  84	.readlink	= generic_readlink,
  85	.follow_link	= befs_fast_follow_link,
  86};
  87
  88static 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 */
 101static int
 102befs_readpage(struct file *file, struct page *page)
 103{
 104	return block_read_full_page(page, befs_get_block);
 105}
 106
 107static sector_t
 108befs_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
 124static int
 125befs_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
 171static struct dentry *
 172befs_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
 222static int
 223befs_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
 238more:
 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
 288static struct inode *
 289befs_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
 299static 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
 305static void befs_destroy_inode(struct inode *inode)
 306{
 307	call_rcu(&inode->i_rcu, befs_i_callback);
 308}
 309
 310static 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
 317static 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 */
 451static int __init
 452befs_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 */
 470static void
 471befs_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 */
 486static void *
 487befs_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
 517static void *
 518befs_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
 533static int
 534befs_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
 613static int
 614befs_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 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 674enum {
 675	Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
 676};
 677
 678static 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
 686static int
 687parse_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 */
 767static void
 768befs_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 */
 783static int
 784befs_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
 913static int
 914befs_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
 922static int
 923befs_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
 946static struct dentry *
 947befs_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
 953static 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};
 960MODULE_ALIAS_FS("befs");
 961
 962static int __init
 963init_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
 979unacquire_inodecache:
 980	befs_destroy_inodecache();
 981
 982unacquire_none:
 983	return err;
 984}
 985
 986static void __exit
 987exit_befs_fs(void)
 988{
 989	befs_destroy_inodecache();
 990
 991	unregister_filesystem(&befs_fs_type);
 992}
 993
 994/*
 995Macros that typecheck the init and exit functions,
 996ensures that they are called at init and cleanup,
 997and eliminates warnings about unused functions.
 998*/
 999module_init(init_befs_fs)
1000module_exit(exit_befs_fs)