1/*
  2 * linux/fs/befs/linuxvfs.c
  3 *
  4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
  5 *
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/slab.h>
 10#include <linux/fs.h>
 11#include <linux/errno.h>
 12#include <linux/stat.h>
 13#include <linux/nls.h>
 14#include <linux/buffer_head.h>
 15#include <linux/vfs.h>
 16#include <linux/parser.h>
 17#include <linux/namei.h>
 18
 19#include "befs.h"
 20#include "btree.h"
 21#include "inode.h"
 22#include "datastream.h"
 23#include "super.h"
 24#include "io.h"
 25
 26MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
 27MODULE_AUTHOR("Will Dyson");
 28MODULE_LICENSE("GPL");
 29
 30/* The units the vfs expects inode->i_blocks to be in */
 31#define VFS_BLOCK_SIZE 512
 32
 33static int befs_readdir(struct file *, void *, filldir_t);
 34static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
 35static int befs_readpage(struct file *file, struct page *page);
 36static sector_t befs_bmap(struct address_space *mapping, sector_t block);
 37static struct dentry *befs_lookup(struct inode *, struct dentry *, struct nameidata *);
 38static struct inode *befs_iget(struct super_block *, unsigned long);
 39static struct inode *befs_alloc_inode(struct super_block *sb);
 40static void befs_destroy_inode(struct inode *inode);
 41static int befs_init_inodecache(void);
 42static void befs_destroy_inodecache(void);
 43static void *befs_follow_link(struct dentry *, struct nameidata *);
 44static void befs_put_link(struct dentry *, struct nameidata *, void *);
 45static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
 46			char **out, int *out_len);
 47static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
 48			char **out, int *out_len);
 49static void befs_put_super(struct super_block *);
 50static int befs_remount(struct super_block *, int *, char *);
 51static int befs_statfs(struct dentry *, struct kstatfs *);
 52static int parse_options(char *, befs_mount_options *);
 53
 54static const struct super_operations befs_sops = {
 55	.alloc_inode	= befs_alloc_inode,	/* allocate a new inode */
 56	.destroy_inode	= befs_destroy_inode, /* deallocate an inode */
 57	.put_super	= befs_put_super,	/* uninit super */
 58	.statfs		= befs_statfs,	/* statfs */
 59	.remount_fs	= befs_remount,
 60	.show_options	= generic_show_options,
 61};
 62
 63/* slab cache for befs_inode_info objects */
 64static struct kmem_cache *befs_inode_cachep;
 65
 66static const struct file_operations befs_dir_operations = {
 67	.read		= generic_read_dir,
 68	.readdir	= befs_readdir,
 69	.llseek		= generic_file_llseek,
 70};
 71
 72static const struct inode_operations befs_dir_inode_operations = {
 73	.lookup		= befs_lookup,
 74};
 75
 76static const struct address_space_operations befs_aops = {
 77	.readpage	= befs_readpage,
 78	.bmap		= befs_bmap,
 79};
 80
 81static const struct inode_operations befs_symlink_inode_operations = {
 82	.readlink	= generic_readlink,
 83	.follow_link	= befs_follow_link,
 84	.put_link	= befs_put_link,
 85};
 86
 87/* 
 88 * Called by generic_file_read() to read a page of data
 89 * 
 90 * In turn, simply calls a generic block read function and
 91 * passes it the address of befs_get_block, for mapping file
 92 * positions to disk blocks.
 93 */
 94static int
 95befs_readpage(struct file *file, struct page *page)
 96{
 97	return block_read_full_page(page, befs_get_block);
 98}
 99
100static sector_t
101befs_bmap(struct address_space *mapping, sector_t block)
102{
103	return generic_block_bmap(mapping, block, befs_get_block);
104}
105
106/* 
107 * Generic function to map a file position (block) to a 
108 * disk offset (passed back in bh_result).
109 *
110 * Used by many higher level functions.
111 *
112 * Calls befs_fblock2brun() in datastream.c to do the real work.
113 *
114 * -WD 10-26-01
115 */
116
117static int
118befs_get_block(struct inode *inode, sector_t block,
119	       struct buffer_head *bh_result, int create)
120{
121	struct super_block *sb = inode->i_sb;
122	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
123	befs_block_run run = BAD_IADDR;
124	int res = 0;
125	ulong disk_off;
126
127	befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
128		   inode->i_ino, block);
129
130	if (block < 0) {
131		befs_error(sb, "befs_get_block() was asked for a block "
132			   "number less than zero: block %ld in inode %lu",
133			   block, inode->i_ino);
134		return -EIO;
135	}
136
137	if (create) {
138		befs_error(sb, "befs_get_block() was asked to write to "
139			   "block %ld in inode %lu", block, inode->i_ino);
140		return -EPERM;
141	}
142
143	res = befs_fblock2brun(sb, ds, block, &run);
144	if (res != BEFS_OK) {
145		befs_error(sb,
146			   "<--- befs_get_block() for inode %lu, block "
147			   "%ld ERROR", inode->i_ino, block);
148		return -EFBIG;
149	}
150
151	disk_off = (ulong) iaddr2blockno(sb, &run);
152
153	map_bh(bh_result, inode->i_sb, disk_off);
154
155	befs_debug(sb, "<--- befs_get_block() for inode %lu, block %ld, "
156		   "disk address %lu", inode->i_ino, block, disk_off);
157
158	return 0;
159}
160
161static struct dentry *
162befs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
163{
164	struct inode *inode = NULL;
165	struct super_block *sb = dir->i_sb;
166	befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
167	befs_off_t offset;
168	int ret;
169	int utfnamelen;
170	char *utfname;
171	const char *name = dentry->d_name.name;
172
173	befs_debug(sb, "---> befs_lookup() "
174		   "name %s inode %ld", dentry->d_name.name, dir->i_ino);
175
176	/* Convert to UTF-8 */
177	if (BEFS_SB(sb)->nls) {
178		ret =
179		    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
180		if (ret < 0) {
181			befs_debug(sb, "<--- befs_lookup() ERROR");
182			return ERR_PTR(ret);
183		}
184		ret = befs_btree_find(sb, ds, utfname, &offset);
185		kfree(utfname);
186
187	} else {
188		ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
189	}
190
191	if (ret == BEFS_BT_NOT_FOUND) {
192		befs_debug(sb, "<--- befs_lookup() %s not found",
193			   dentry->d_name.name);
194		return ERR_PTR(-ENOENT);
195
196	} else if (ret != BEFS_OK || offset == 0) {
197		befs_warning(sb, "<--- befs_lookup() Error");
198		return ERR_PTR(-ENODATA);
199	}
200
201	inode = befs_iget(dir->i_sb, (ino_t) offset);
202	if (IS_ERR(inode))
203		return ERR_CAST(inode);
204
205	d_add(dentry, inode);
206
207	befs_debug(sb, "<--- befs_lookup()");
208
209	return NULL;
210}
211
212static int
213befs_readdir(struct file *filp, void *dirent, filldir_t filldir)
214{
215	struct inode *inode = filp->f_path.dentry->d_inode;
216	struct super_block *sb = inode->i_sb;
217	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
218	befs_off_t value;
219	int result;
220	size_t keysize;
221	unsigned char d_type;
222	char keybuf[BEFS_NAME_LEN + 1];
223	char *nlsname;
224	int nlsnamelen;
225	const char *dirname = filp->f_path.dentry->d_name.name;
226
227	befs_debug(sb, "---> befs_readdir() "
228		   "name %s, inode %ld, filp->f_pos %Ld",
229		   dirname, inode->i_ino, filp->f_pos);
230
231	result = befs_btree_read(sb, ds, filp->f_pos, BEFS_NAME_LEN + 1,
232				 keybuf, &keysize, &value);
233
234	if (result == BEFS_ERR) {
235		befs_debug(sb, "<--- befs_readdir() ERROR");
236		befs_error(sb, "IO error reading %s (inode %lu)",
237			   dirname, inode->i_ino);
238		return -EIO;
239
240	} else if (result == BEFS_BT_END) {
241		befs_debug(sb, "<--- befs_readdir() END");
242		return 0;
243
244	} else if (result == BEFS_BT_EMPTY) {
245		befs_debug(sb, "<--- befs_readdir() Empty directory");
246		return 0;
247	}
248
249	d_type = DT_UNKNOWN;
250
251	/* Convert to NLS */
252	if (BEFS_SB(sb)->nls) {
253		result =
254		    befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
255		if (result < 0) {
256			befs_debug(sb, "<--- befs_readdir() ERROR");
257			return result;
258		}
259		result = filldir(dirent, nlsname, nlsnamelen, filp->f_pos,
260				 (ino_t) value, d_type);
261		kfree(nlsname);
262
263	} else {
264		result = filldir(dirent, keybuf, keysize, filp->f_pos,
265				 (ino_t) value, d_type);
266	}
267
268	filp->f_pos++;
269
270	befs_debug(sb, "<--- befs_readdir() filp->f_pos %Ld", filp->f_pos);
271
272	return 0;
273}
274
275static struct inode *
276befs_alloc_inode(struct super_block *sb)
277{
278        struct befs_inode_info *bi;
279        bi = (struct befs_inode_info *)kmem_cache_alloc(befs_inode_cachep,
280							GFP_KERNEL);
281        if (!bi)
282                return NULL;
283        return &bi->vfs_inode;
284}
285
286static void befs_i_callback(struct rcu_head *head)
287{
288	struct inode *inode = container_of(head, struct inode, i_rcu);
289	INIT_LIST_HEAD(&inode->i_dentry);
290        kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
291}
292
293static void befs_destroy_inode(struct inode *inode)
294{
295	call_rcu(&inode->i_rcu, befs_i_callback);
296}
297
298static void init_once(void *foo)
299{
300        struct befs_inode_info *bi = (struct befs_inode_info *) foo;
301
302	inode_init_once(&bi->vfs_inode);
303}
304
305static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
306{
307	struct buffer_head *bh = NULL;
308	befs_inode *raw_inode = NULL;
309
310	befs_sb_info *befs_sb = BEFS_SB(sb);
311	befs_inode_info *befs_ino = NULL;
312	struct inode *inode;
313	long ret = -EIO;
314
315	befs_debug(sb, "---> befs_read_inode() " "inode = %lu", ino);
316
317	inode = iget_locked(sb, ino);
318	if (IS_ERR(inode))
319		return inode;
320	if (!(inode->i_state & I_NEW))
321		return inode;
322
323	befs_ino = BEFS_I(inode);
324
325	/* convert from vfs's inode number to befs's inode number */
326	befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
327
328	befs_debug(sb, "  real inode number [%u, %hu, %hu]",
329		   befs_ino->i_inode_num.allocation_group,
330		   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
331
332	bh = befs_bread(sb, inode->i_ino);
333	if (!bh) {
334		befs_error(sb, "unable to read inode block - "
335			   "inode = %lu", inode->i_ino);
336		goto unacquire_none;
337	}
338
339	raw_inode = (befs_inode *) bh->b_data;
340
341	befs_dump_inode(sb, raw_inode);
342
343	if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
344		befs_error(sb, "Bad inode: %lu", inode->i_ino);
345		goto unacquire_bh;
346	}
347
348	inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
349
350	/*
351	 * set uid and gid.  But since current BeOS is single user OS, so
352	 * you can change by "uid" or "gid" options.
353	 */   
354
355	inode->i_uid = befs_sb->mount_opts.use_uid ?
356	    befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
357	inode->i_gid = befs_sb->mount_opts.use_gid ?
358	    befs_sb->mount_opts.gid : (gid_t) fs32_to_cpu(sb, raw_inode->gid);
359
360	inode->i_nlink = 1;
361
362	/*
363	 * BEFS's time is 64 bits, but current VFS is 32 bits...
364	 * BEFS don't have access time. Nor inode change time. VFS
365	 * doesn't have creation time.
366	 * Also, the lower 16 bits of the last_modified_time and 
367	 * create_time are just a counter to help ensure uniqueness
368	 * for indexing purposes. (PFD, page 54)
369	 */
370
371	inode->i_mtime.tv_sec =
372	    fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
373	inode->i_mtime.tv_nsec = 0;   /* lower 16 bits are not a time */	
374	inode->i_ctime = inode->i_mtime;
375	inode->i_atime = inode->i_mtime;
376
377	befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
378	befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
379	befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
380	befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
381
382	if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
383		inode->i_size = 0;
384		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
385		strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
386			BEFS_SYMLINK_LEN - 1);
387		befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
388	} else {
389		int num_blks;
390
391		befs_ino->i_data.ds =
392		    fsds_to_cpu(sb, &raw_inode->data.datastream);
393
394		num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
395		inode->i_blocks =
396		    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
397		inode->i_size = befs_ino->i_data.ds.size;
398	}
399
400	inode->i_mapping->a_ops = &befs_aops;
401
402	if (S_ISREG(inode->i_mode)) {
403		inode->i_fop = &generic_ro_fops;
404	} else if (S_ISDIR(inode->i_mode)) {
405		inode->i_op = &befs_dir_inode_operations;
406		inode->i_fop = &befs_dir_operations;
407	} else if (S_ISLNK(inode->i_mode)) {
408		inode->i_op = &befs_symlink_inode_operations;
409	} else {
410		befs_error(sb, "Inode %lu is not a regular file, "
411			   "directory or symlink. THAT IS WRONG! BeFS has no "
412			   "on disk special files", inode->i_ino);
413		goto unacquire_bh;
414	}
415
416	brelse(bh);
417	befs_debug(sb, "<--- befs_read_inode()");
418	unlock_new_inode(inode);
419	return inode;
420
421      unacquire_bh:
422	brelse(bh);
423
424      unacquire_none:
425	iget_failed(inode);
426	befs_debug(sb, "<--- befs_read_inode() - Bad inode");
427	return ERR_PTR(ret);
428}
429
430/* Initialize the inode cache. Called at fs setup.
431 *
432 * Taken from NFS implementation by Al Viro.
433 */
434static int
435befs_init_inodecache(void)
436{
437	befs_inode_cachep = kmem_cache_create("befs_inode_cache",
438					      sizeof (struct befs_inode_info),
439					      0, (SLAB_RECLAIM_ACCOUNT|
440						SLAB_MEM_SPREAD),
441					      init_once);
442	if (befs_inode_cachep == NULL) {
443		printk(KERN_ERR "befs_init_inodecache: "
444		       "Couldn't initialize inode slabcache\n");
445		return -ENOMEM;
446	}
447
448	return 0;
449}
450
451/* Called at fs teardown.
452 * 
453 * Taken from NFS implementation by Al Viro.
454 */
455static void
456befs_destroy_inodecache(void)
457{
458	kmem_cache_destroy(befs_inode_cachep);
459}
460
461/*
462 * The inode of symbolic link is different to data stream.
463 * The data stream become link name. Unless the LONG_SYMLINK
464 * flag is set.
465 */
466static void *
467befs_follow_link(struct dentry *dentry, struct nameidata *nd)
468{
469	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
470	char *link;
471
472	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
473		struct super_block *sb = dentry->d_sb;
474		befs_data_stream *data = &befs_ino->i_data.ds;
475		befs_off_t len = data->size;
476
477		if (len == 0) {
478			befs_error(sb, "Long symlink with illegal length");
479			link = ERR_PTR(-EIO);
480		} else {
481			befs_debug(sb, "Follow long symlink");
482
483			link = kmalloc(len, GFP_NOFS);
484			if (!link) {
485				link = ERR_PTR(-ENOMEM);
486			} else if (befs_read_lsymlink(sb, data, link, len) != len) {
487				kfree(link);
488				befs_error(sb, "Failed to read entire long symlink");
489				link = ERR_PTR(-EIO);
490			} else {
491				link[len - 1] = '\0';
492			}
493		}
494	} else {
495		link = befs_ino->i_data.symlink;
496	}
497
498	nd_set_link(nd, link);
499	return NULL;
500}
501
502static void befs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
503{
504	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
505	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
506		char *link = nd_get_link(nd);
507		if (!IS_ERR(link))
508			kfree(link);
509	}
510}
511
512/*
513 * UTF-8 to NLS charset  convert routine
514 * 
515 *
516 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
517 * the nls tables directly
518 */
519
520static int
521befs_utf2nls(struct super_block *sb, const char *in,
522	     int in_len, char **out, int *out_len)
523{
524	struct nls_table *nls = BEFS_SB(sb)->nls;
525	int i, o;
526	unicode_t uni;
527	int unilen, utflen;
528	char *result;
529	/* The utf8->nls conversion won't make the final nls string bigger
530	 * than the utf one, but if the string is pure ascii they'll have the
531	 * same width and an extra char is needed to save the additional \0
532	 */
533	int maxlen = in_len + 1;
534
535	befs_debug(sb, "---> utf2nls()");
536
537	if (!nls) {
538		befs_error(sb, "befs_utf2nls called with no NLS table loaded");
539		return -EINVAL;
540	}
541
542	*out = result = kmalloc(maxlen, GFP_NOFS);
543	if (!*out) {
544		befs_error(sb, "befs_utf2nls() cannot allocate memory");
545		*out_len = 0;
546		return -ENOMEM;
547	}
548
549	for (i = o = 0; i < in_len; i += utflen, o += unilen) {
550
551		/* convert from UTF-8 to Unicode */
552		utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
553		if (utflen < 0)
554			goto conv_err;
555
556		/* convert from Unicode to nls */
557		if (uni > MAX_WCHAR_T)
558			goto conv_err;
559		unilen = nls->uni2char(uni, &result[o], in_len - o);
560		if (unilen < 0)
561			goto conv_err;
562	}
563	result[o] = '\0';
564	*out_len = o;
565
566	befs_debug(sb, "<--- utf2nls()");
567
568	return o;
569
570      conv_err:
571	befs_error(sb, "Name using character set %s contains a character that "
572		   "cannot be converted to unicode.", nls->charset);
573	befs_debug(sb, "<--- utf2nls()");
574	kfree(result);
575	return -EILSEQ;
576}
577
578/**
579 * befs_nls2utf - Convert NLS string to utf8 encodeing
580 * @sb: Superblock
581 * @src: Input string buffer in NLS format
582 * @srclen: Length of input string in bytes
583 * @dest: The output string in UTF-8 format
584 * @destlen: Length of the output buffer
585 * 
586 * Converts input string @src, which is in the format of the loaded NLS map,
587 * into a utf8 string.
588 * 
589 * The destination string @dest is allocated by this function and the caller is
590 * responsible for freeing it with kfree()
591 * 
592 * On return, *@destlen is the length of @dest in bytes.
593 *
594 * On success, the return value is the number of utf8 characters written to
595 * the output buffer @dest.
596 *  
597 * On Failure, a negative number coresponding to the error code is returned.
598 */
599
600static int
601befs_nls2utf(struct super_block *sb, const char *in,
602	     int in_len, char **out, int *out_len)
603{
604	struct nls_table *nls = BEFS_SB(sb)->nls;
605	int i, o;
606	wchar_t uni;
607	int unilen, utflen;
608	char *result;
609	/* There're nls characters that will translate to 3-chars-wide UTF-8
610	 * characters, a additional byte is needed to save the final \0
611	 * in special cases */
612	int maxlen = (3 * in_len) + 1;
613
614	befs_debug(sb, "---> nls2utf()\n");
615
616	if (!nls) {
617		befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
618		return -EINVAL;
619	}
620
621	*out = result = kmalloc(maxlen, GFP_NOFS);
622	if (!*out) {
623		befs_error(sb, "befs_nls2utf() cannot allocate memory");
624		*out_len = 0;
625		return -ENOMEM;
626	}
627
628	for (i = o = 0; i < in_len; i += unilen, o += utflen) {
629
630		/* convert from nls to unicode */
631		unilen = nls->char2uni(&in[i], in_len - i, &uni);
632		if (unilen < 0)
633			goto conv_err;
634
635		/* convert from unicode to UTF-8 */
636		utflen = utf32_to_utf8(uni, &result[o], 3);
637		if (utflen <= 0)
638			goto conv_err;
639	}
640
641	result[o] = '\0';
642	*out_len = o;
643
644	befs_debug(sb, "<--- nls2utf()");
645
646	return i;
647
648      conv_err:
649	befs_error(sb, "Name using charecter set %s contains a charecter that "
650		   "cannot be converted to unicode.", nls->charset);
651	befs_debug(sb, "<--- nls2utf()");
652	kfree(result);
653	return -EILSEQ;
654}
655
656/**
657 * Use the
658 *
659 */
660enum {
661	Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
662};
663
664static const match_table_t befs_tokens = {
665	{Opt_uid, "uid=%d"},
666	{Opt_gid, "gid=%d"},
667	{Opt_charset, "iocharset=%s"},
668	{Opt_debug, "debug"},
669	{Opt_err, NULL}
670};
671
672static int
673parse_options(char *options, befs_mount_options * opts)
674{
675	char *p;
676	substring_t args[MAX_OPT_ARGS];
677	int option;
678
679	/* Initialize options */
680	opts->uid = 0;
681	opts->gid = 0;
682	opts->use_uid = 0;
683	opts->use_gid = 0;
684	opts->iocharset = NULL;
685	opts->debug = 0;
686
687	if (!options)
688		return 1;
689
690	while ((p = strsep(&options, ",")) != NULL) {
691		int token;
692		if (!*p)
693			continue;
694
695		token = match_token(p, befs_tokens, args);
696		switch (token) {
697		case Opt_uid:
698			if (match_int(&args[0], &option))
699				return 0;
700			if (option < 0) {
701				printk(KERN_ERR "BeFS: Invalid uid %d, "
702						"using default\n", option);
703				break;
704			}
705			opts->uid = option;
706			opts->use_uid = 1;
707			break;
708		case Opt_gid:
709			if (match_int(&args[0], &option))
710				return 0;
711			if (option < 0) {
712				printk(KERN_ERR "BeFS: Invalid gid %d, "
713						"using default\n", option);
714				break;
715			}
716			opts->gid = option;
717			opts->use_gid = 1;
718			break;
719		case Opt_charset:
720			kfree(opts->iocharset);
721			opts->iocharset = match_strdup(&args[0]);
722			if (!opts->iocharset) {
723				printk(KERN_ERR "BeFS: allocation failure for "
724						"iocharset string\n");
725				return 0;
726			}
727			break;
728		case Opt_debug:
729			opts->debug = 1;
730			break;
731		default:
732			printk(KERN_ERR "BeFS: Unrecognized mount option \"%s\" "
733					"or missing value\n", p);
734			return 0;
735		}
736	}
737	return 1;
738}
739
740/* This function has the responsibiltiy of getting the
741 * filesystem ready for unmounting. 
742 * Basically, we free everything that we allocated in
743 * befs_read_inode
744 */
745static void
746befs_put_super(struct super_block *sb)
747{
748	kfree(BEFS_SB(sb)->mount_opts.iocharset);
749	BEFS_SB(sb)->mount_opts.iocharset = NULL;
750	unload_nls(BEFS_SB(sb)->nls);
751	kfree(sb->s_fs_info);
752	sb->s_fs_info = NULL;
753}
754
755/* Allocate private field of the superblock, fill it.
756 *
757 * Finish filling the public superblock fields
758 * Make the root directory
759 * Load a set of NLS translations if needed.
760 */
761static int
762befs_fill_super(struct super_block *sb, void *data, int silent)
763{
764	struct buffer_head *bh;
765	befs_sb_info *befs_sb;
766	befs_super_block *disk_sb;
767	struct inode *root;
768	long ret = -EINVAL;
769	const unsigned long sb_block = 0;
770	const off_t x86_sb_off = 512;
771
772	save_mount_options(sb, data);
773
774	sb->s_fs_info = kmalloc(sizeof (*befs_sb), GFP_KERNEL);
775	if (sb->s_fs_info == NULL) {
776		printk(KERN_ERR
777		       "BeFS(%s): Unable to allocate memory for private "
778		       "portion of superblock. Bailing.\n", sb->s_id);
779		goto unacquire_none;
780	}
781	befs_sb = BEFS_SB(sb);
782	memset(befs_sb, 0, sizeof(befs_sb_info));
783
784	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
785		befs_error(sb, "cannot parse mount options");
786		goto unacquire_priv_sbp;
787	}
788
789	befs_debug(sb, "---> befs_fill_super()");
790
791#ifndef CONFIG_BEFS_RW
792	if (!(sb->s_flags & MS_RDONLY)) {
793		befs_warning(sb,
794			     "No write support. Marking filesystem read-only");
795		sb->s_flags |= MS_RDONLY;
796	}
797#endif				/* CONFIG_BEFS_RW */
798
799	/*
800	 * Set dummy blocksize to read super block.
801	 * Will be set to real fs blocksize later.
802	 *
803	 * Linux 2.4.10 and later refuse to read blocks smaller than
804	 * the hardsect size for the device. But we also need to read at 
805	 * least 1k to get the second 512 bytes of the volume.
806	 * -WD 10-26-01
807	 */ 
808	sb_min_blocksize(sb, 1024);
809
810	if (!(bh = sb_bread(sb, sb_block))) {
811		befs_error(sb, "unable to read superblock");
812		goto unacquire_priv_sbp;
813	}
814
815	/* account for offset of super block on x86 */
816	disk_sb = (befs_super_block *) bh->b_data;
817	if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
818	    (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
819		befs_debug(sb, "Using PPC superblock location");
820	} else {
821		befs_debug(sb, "Using x86 superblock location");
822		disk_sb =
823		    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
824	}
825
826	if (befs_load_sb(sb, disk_sb) != BEFS_OK)
827		goto unacquire_bh;
828
829	befs_dump_super_block(sb, disk_sb);
830
831	brelse(bh);
832
833	if (befs_check_sb(sb) != BEFS_OK)
834		goto unacquire_priv_sbp;
835
836	if( befs_sb->num_blocks > ~((sector_t)0) ) {
837		befs_error(sb, "blocks count: %Lu "
838			"is larger than the host can use",
839			befs_sb->num_blocks);
840		goto unacquire_priv_sbp;
841	}
842
843	/*
844	 * set up enough so that it can read an inode
845	 * Fill in kernel superblock fields from private sb
846	 */
847	sb->s_magic = BEFS_SUPER_MAGIC;
848	/* Set real blocksize of fs */
849	sb_set_blocksize(sb, (ulong) befs_sb->block_size);
850	sb->s_op = &befs_sops;
851	root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
852	if (IS_ERR(root)) {
853		ret = PTR_ERR(root);
854		goto unacquire_priv_sbp;
855	}
856	sb->s_root = d_alloc_root(root);
857	if (!sb->s_root) {
858		iput(root);
859		befs_error(sb, "get root inode failed");
860		goto unacquire_priv_sbp;
861	}
862
863	/* load nls library */
864	if (befs_sb->mount_opts.iocharset) {
865		befs_debug(sb, "Loading nls: %s",
866			   befs_sb->mount_opts.iocharset);
867		befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
868		if (!befs_sb->nls) {
869			befs_warning(sb, "Cannot load nls %s"
870					" loading default nls",
871					befs_sb->mount_opts.iocharset);
872			befs_sb->nls = load_nls_default();
873		}
874	/* load default nls if none is specified  in mount options */
875	} else {
876		befs_debug(sb, "Loading default nls");
877		befs_sb->nls = load_nls_default();
878	}
879
880	return 0;
881/*****************/
882      unacquire_bh:
883	brelse(bh);
884
885      unacquire_priv_sbp:
886	kfree(befs_sb->mount_opts.iocharset);
887	kfree(sb->s_fs_info);
888
889      unacquire_none:
890	sb->s_fs_info = NULL;
891	return ret;
892}
893
894static int
895befs_remount(struct super_block *sb, int *flags, char *data)
896{
897	if (!(*flags & MS_RDONLY))
898		return -EINVAL;
899	return 0;
900}
901
902static int
903befs_statfs(struct dentry *dentry, struct kstatfs *buf)
904{
905	struct super_block *sb = dentry->d_sb;
906	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
907
908	befs_debug(sb, "---> befs_statfs()");
909
910	buf->f_type = BEFS_SUPER_MAGIC;
911	buf->f_bsize = sb->s_blocksize;
912	buf->f_blocks = BEFS_SB(sb)->num_blocks;
913	buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
914	buf->f_bavail = buf->f_bfree;
915	buf->f_files = 0;	/* UNKNOWN */
916	buf->f_ffree = 0;	/* UNKNOWN */
917	buf->f_fsid.val[0] = (u32)id;
918	buf->f_fsid.val[1] = (u32)(id >> 32);
919	buf->f_namelen = BEFS_NAME_LEN;
920
921	befs_debug(sb, "<--- befs_statfs()");
922
923	return 0;
924}
925
926static struct dentry *
927befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
928	    void *data)
929{
930	return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
931}
932
933static struct file_system_type befs_fs_type = {
934	.owner		= THIS_MODULE,
935	.name		= "befs",
936	.mount		= befs_mount,
937	.kill_sb	= kill_block_super,
938	.fs_flags	= FS_REQUIRES_DEV,	
939};
940
941static int __init
942init_befs_fs(void)
943{
944	int err;
945
946	printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
947
948	err = befs_init_inodecache();
949	if (err)
950		goto unacquire_none;
951
952	err = register_filesystem(&befs_fs_type);
953	if (err)
954		goto unacquire_inodecache;
955
956	return 0;
957
958unacquire_inodecache:
959	befs_destroy_inodecache();
960
961unacquire_none:
962	return err;
963}
964
965static void __exit
966exit_befs_fs(void)
967{
968	befs_destroy_inodecache();
969
970	unregister_filesystem(&befs_fs_type);
971}
972
973/*
974Macros that typecheck the init and exit functions,
975ensures that they are called at init and cleanup,
976and eliminates warnings about unused functions.
977*/
978module_init(init_befs_fs)
979module_exit(exit_befs_fs)