xref: /linux/fs/befs/linuxvfs.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
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 #include "endian.h"
26 
27 MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
28 MODULE_AUTHOR("Will Dyson");
29 MODULE_LICENSE("GPL");
30 
31 /* The units the vfs expects inode->i_blocks to be in */
32 #define VFS_BLOCK_SIZE 512
33 
34 static int befs_readdir(struct file *, void *, filldir_t);
35 static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
36 static int befs_readpage(struct file *file, struct page *page);
37 static sector_t befs_bmap(struct address_space *mapping, sector_t block);
38 static struct dentry *befs_lookup(struct inode *, struct dentry *, struct nameidata *);
39 static void befs_read_inode(struct inode *ino);
40 static struct inode *befs_alloc_inode(struct super_block *sb);
41 static void befs_destroy_inode(struct inode *inode);
42 static int befs_init_inodecache(void);
43 static void befs_destroy_inodecache(void);
44 static void *befs_follow_link(struct dentry *, struct nameidata *);
45 static void befs_put_link(struct dentry *, struct nameidata *, void *);
46 static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
47 			char **out, int *out_len);
48 static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
49 			char **out, int *out_len);
50 static void befs_put_super(struct super_block *);
51 static int befs_remount(struct super_block *, int *, char *);
52 static int befs_statfs(struct super_block *, struct kstatfs *);
53 static int parse_options(char *, befs_mount_options *);
54 
55 static const struct super_operations befs_sops = {
56 	.read_inode	= befs_read_inode,	/* initialize & read inode */
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 };
63 
64 /* slab cache for befs_inode_info objects */
65 static kmem_cache_t *befs_inode_cachep;
66 
67 static const struct file_operations befs_dir_operations = {
68 	.read		= generic_read_dir,
69 	.readdir	= befs_readdir,
70 };
71 
72 static struct inode_operations befs_dir_inode_operations = {
73 	.lookup		= befs_lookup,
74 };
75 
76 static struct address_space_operations befs_aops = {
77 	.readpage	= befs_readpage,
78 	.sync_page	= block_sync_page,
79 	.bmap		= befs_bmap,
80 };
81 
82 static struct inode_operations befs_symlink_inode_operations = {
83 	.readlink	= generic_readlink,
84 	.follow_link	= befs_follow_link,
85 	.put_link	= befs_put_link,
86 };
87 
88 /*
89  * Called by generic_file_read() to read a page of data
90  *
91  * In turn, simply calls a generic block read function and
92  * passes it the address of befs_get_block, for mapping file
93  * positions to disk blocks.
94  */
95 static int
96 befs_readpage(struct file *file, struct page *page)
97 {
98 	return block_read_full_page(page, befs_get_block);
99 }
100 
101 static sector_t
102 befs_bmap(struct address_space *mapping, sector_t block)
103 {
104 	return generic_block_bmap(mapping, block, befs_get_block);
105 }
106 
107 /*
108  * Generic function to map a file position (block) to a
109  * disk offset (passed back in bh_result).
110  *
111  * Used by many higher level functions.
112  *
113  * Calls befs_fblock2brun() in datastream.c to do the real work.
114  *
115  * -WD 10-26-01
116  */
117 
118 static int
119 befs_get_block(struct inode *inode, sector_t block,
120 	       struct buffer_head *bh_result, int create)
121 {
122 	struct super_block *sb = inode->i_sb;
123 	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
124 	befs_block_run run = BAD_IADDR;
125 	int res = 0;
126 	ulong disk_off;
127 
128 	befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
129 		   inode->i_ino, block);
130 
131 	if (block < 0) {
132 		befs_error(sb, "befs_get_block() was asked for a block "
133 			   "number less than zero: block %ld in inode %lu",
134 			   block, inode->i_ino);
135 		return -EIO;
136 	}
137 
138 	if (create) {
139 		befs_error(sb, "befs_get_block() was asked to write to "
140 			   "block %ld in inode %lu", block, inode->i_ino);
141 		return -EPERM;
142 	}
143 
144 	res = befs_fblock2brun(sb, ds, block, &run);
145 	if (res != BEFS_OK) {
146 		befs_error(sb,
147 			   "<--- befs_get_block() for inode %lu, block "
148 			   "%ld ERROR", inode->i_ino, block);
149 		return -EFBIG;
150 	}
151 
152 	disk_off = (ulong) iaddr2blockno(sb, &run);
153 
154 	map_bh(bh_result, inode->i_sb, disk_off);
155 
156 	befs_debug(sb, "<--- befs_get_block() for inode %lu, block %ld, "
157 		   "disk address %lu", inode->i_ino, block, disk_off);
158 
159 	return 0;
160 }
161 
162 static struct dentry *
163 befs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
164 {
165 	struct inode *inode = NULL;
166 	struct super_block *sb = dir->i_sb;
167 	befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
168 	befs_off_t offset;
169 	int ret;
170 	int utfnamelen;
171 	char *utfname;
172 	const char *name = dentry->d_name.name;
173 
174 	befs_debug(sb, "---> befs_lookup() "
175 		   "name %s inode %ld", dentry->d_name.name, dir->i_ino);
176 
177 	/* Convert to UTF-8 */
178 	if (BEFS_SB(sb)->nls) {
179 		ret =
180 		    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
181 		if (ret < 0) {
182 			befs_debug(sb, "<--- befs_lookup() ERROR");
183 			return ERR_PTR(ret);
184 		}
185 		ret = befs_btree_find(sb, ds, utfname, &offset);
186 		kfree(utfname);
187 
188 	} else {
189 		ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
190 	}
191 
192 	if (ret == BEFS_BT_NOT_FOUND) {
193 		befs_debug(sb, "<--- befs_lookup() %s not found",
194 			   dentry->d_name.name);
195 		return ERR_PTR(-ENOENT);
196 
197 	} else if (ret != BEFS_OK || offset == 0) {
198 		befs_warning(sb, "<--- befs_lookup() Error");
199 		return ERR_PTR(-ENODATA);
200 	}
201 
202 	inode = iget(dir->i_sb, (ino_t) offset);
203 	if (!inode)
204 		return ERR_PTR(-EACCES);
205 
206 	d_add(dentry, inode);
207 
208 	befs_debug(sb, "<--- befs_lookup()");
209 
210 	return NULL;
211 }
212 
213 static int
214 befs_readdir(struct file *filp, void *dirent, filldir_t filldir)
215 {
216 	struct inode *inode = filp->f_dentry->d_inode;
217 	struct super_block *sb = inode->i_sb;
218 	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
219 	befs_off_t value;
220 	int result;
221 	size_t keysize;
222 	unsigned char d_type;
223 	char keybuf[BEFS_NAME_LEN + 1];
224 	char *nlsname;
225 	int nlsnamelen;
226 	const char *dirname = filp->f_dentry->d_name.name;
227 
228 	befs_debug(sb, "---> befs_readdir() "
229 		   "name %s, inode %ld, filp->f_pos %Ld",
230 		   dirname, inode->i_ino, filp->f_pos);
231 
232 	result = befs_btree_read(sb, ds, filp->f_pos, BEFS_NAME_LEN + 1,
233 				 keybuf, &keysize, &value);
234 
235 	if (result == BEFS_ERR) {
236 		befs_debug(sb, "<--- befs_readdir() ERROR");
237 		befs_error(sb, "IO error reading %s (inode %lu)",
238 			   dirname, inode->i_ino);
239 		return -EIO;
240 
241 	} else if (result == BEFS_BT_END) {
242 		befs_debug(sb, "<--- befs_readdir() END");
243 		return 0;
244 
245 	} else if (result == BEFS_BT_EMPTY) {
246 		befs_debug(sb, "<--- befs_readdir() Empty directory");
247 		return 0;
248 	}
249 
250 	d_type = DT_UNKNOWN;
251 
252 	/* Convert to NLS */
253 	if (BEFS_SB(sb)->nls) {
254 		result =
255 		    befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
256 		if (result < 0) {
257 			befs_debug(sb, "<--- befs_readdir() ERROR");
258 			return result;
259 		}
260 		result = filldir(dirent, nlsname, nlsnamelen, filp->f_pos,
261 				 (ino_t) value, d_type);
262 		kfree(nlsname);
263 
264 	} else {
265 		result = filldir(dirent, keybuf, keysize, filp->f_pos,
266 				 (ino_t) value, d_type);
267 	}
268 
269 	filp->f_pos++;
270 
271 	befs_debug(sb, "<--- befs_readdir() filp->f_pos %Ld", filp->f_pos);
272 
273 	return 0;
274 }
275 
276 static struct inode *
277 befs_alloc_inode(struct super_block *sb)
278 {
279         struct befs_inode_info *bi;
280         bi = (struct befs_inode_info *)kmem_cache_alloc(befs_inode_cachep,
281 							SLAB_KERNEL);
282         if (!bi)
283                 return NULL;
284         return &bi->vfs_inode;
285 }
286 
287 static void
288 befs_destroy_inode(struct inode *inode)
289 {
290         kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
291 }
292 
293 static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
294 {
295         struct befs_inode_info *bi = (struct befs_inode_info *) foo;
296 
297 	        if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
298 		            SLAB_CTOR_CONSTRUCTOR) {
299 			inode_init_once(&bi->vfs_inode);
300 		}
301 }
302 
303 static void
304 befs_read_inode(struct inode *inode)
305 {
306 	struct buffer_head *bh = NULL;
307 	befs_inode *raw_inode = NULL;
308 
309 	struct super_block *sb = inode->i_sb;
310 	befs_sb_info *befs_sb = BEFS_SB(sb);
311 	befs_inode_info *befs_ino = NULL;
312 
313 	befs_debug(sb, "---> befs_read_inode() " "inode = %lu", inode->i_ino);
314 
315 	befs_ino = BEFS_I(inode);
316 
317 	/* convert from vfs's inode number to befs's inode number */
318 	befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
319 
320 	befs_debug(sb, "  real inode number [%u, %hu, %hu]",
321 		   befs_ino->i_inode_num.allocation_group,
322 		   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
323 
324 	bh = befs_bread(sb, inode->i_ino);
325 	if (!bh) {
326 		befs_error(sb, "unable to read inode block - "
327 			   "inode = %lu", inode->i_ino);
328 		goto unaquire_none;
329 	}
330 
331 	raw_inode = (befs_inode *) bh->b_data;
332 
333 	befs_dump_inode(sb, raw_inode);
334 
335 	if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
336 		befs_error(sb, "Bad inode: %lu", inode->i_ino);
337 		goto unaquire_bh;
338 	}
339 
340 	inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
341 
342 	/*
343 	 * set uid and gid.  But since current BeOS is single user OS, so
344 	 * you can change by "uid" or "gid" options.
345 	 */
346 
347 	inode->i_uid = befs_sb->mount_opts.use_uid ?
348 	    befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
349 	inode->i_gid = befs_sb->mount_opts.use_gid ?
350 	    befs_sb->mount_opts.gid : (gid_t) fs32_to_cpu(sb, raw_inode->gid);
351 
352 	inode->i_nlink = 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 	inode->i_blksize = befs_sb->block_size;
369 
370 	befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
371 	befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
372 	befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
373 	befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
374 
375 	if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
376 		inode->i_size = 0;
377 		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
378 		strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
379 			BEFS_SYMLINK_LEN);
380 	} else {
381 		int num_blks;
382 
383 		befs_ino->i_data.ds =
384 		    fsds_to_cpu(sb, raw_inode->data.datastream);
385 
386 		num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
387 		inode->i_blocks =
388 		    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
389 		inode->i_size = befs_ino->i_data.ds.size;
390 	}
391 
392 	inode->i_mapping->a_ops = &befs_aops;
393 
394 	if (S_ISREG(inode->i_mode)) {
395 		inode->i_fop = &generic_ro_fops;
396 	} else if (S_ISDIR(inode->i_mode)) {
397 		inode->i_op = &befs_dir_inode_operations;
398 		inode->i_fop = &befs_dir_operations;
399 	} else if (S_ISLNK(inode->i_mode)) {
400 		inode->i_op = &befs_symlink_inode_operations;
401 	} else {
402 		befs_error(sb, "Inode %lu is not a regular file, "
403 			   "directory or symlink. THAT IS WRONG! BeFS has no "
404 			   "on disk special files", inode->i_ino);
405 		goto unaquire_bh;
406 	}
407 
408 	brelse(bh);
409 	befs_debug(sb, "<--- befs_read_inode()");
410 	return;
411 
412       unaquire_bh:
413 	brelse(bh);
414 
415       unaquire_none:
416 	make_bad_inode(inode);
417 	befs_debug(sb, "<--- befs_read_inode() - Bad inode");
418 	return;
419 }
420 
421 /* Initialize the inode cache. Called at fs setup.
422  *
423  * Taken from NFS implementation by Al Viro.
424  */
425 static int
426 befs_init_inodecache(void)
427 {
428 	befs_inode_cachep = kmem_cache_create("befs_inode_cache",
429 					      sizeof (struct befs_inode_info),
430 					      0, (SLAB_RECLAIM_ACCOUNT|
431 						SLAB_MEM_SPREAD),
432 					      init_once, NULL);
433 	if (befs_inode_cachep == NULL) {
434 		printk(KERN_ERR "befs_init_inodecache: "
435 		       "Couldn't initalize inode slabcache\n");
436 		return -ENOMEM;
437 	}
438 
439 	return 0;
440 }
441 
442 /* Called at fs teardown.
443  *
444  * Taken from NFS implementation by Al Viro.
445  */
446 static void
447 befs_destroy_inodecache(void)
448 {
449 	if (kmem_cache_destroy(befs_inode_cachep))
450 		printk(KERN_ERR "befs_destroy_inodecache: "
451 		       "not all structures were freed\n");
452 }
453 
454 /*
455  * The inode of symbolic link is different to data stream.
456  * The data stream become link name. Unless the LONG_SYMLINK
457  * flag is set.
458  */
459 static void *
460 befs_follow_link(struct dentry *dentry, struct nameidata *nd)
461 {
462 	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
463 	char *link;
464 
465 	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
466 		struct super_block *sb = dentry->d_sb;
467 		befs_data_stream *data = &befs_ino->i_data.ds;
468 		befs_off_t len = data->size;
469 
470 		befs_debug(sb, "Follow long symlink");
471 
472 		link = kmalloc(len, GFP_NOFS);
473 		if (!link) {
474 			link = ERR_PTR(-ENOMEM);
475 		} else if (befs_read_lsymlink(sb, data, link, len) != len) {
476 			kfree(link);
477 			befs_error(sb, "Failed to read entire long symlink");
478 			link = ERR_PTR(-EIO);
479 		}
480 	} else {
481 		link = befs_ino->i_data.symlink;
482 	}
483 
484 	nd_set_link(nd, link);
485 	return NULL;
486 }
487 
488 static void befs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
489 {
490 	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
491 	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
492 		char *p = nd_get_link(nd);
493 		if (!IS_ERR(p))
494 			kfree(p);
495 	}
496 }
497 
498 /*
499  * UTF-8 to NLS charset  convert routine
500  *
501  *
502  * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
503  * the nls tables directly
504  */
505 
506 static int
507 befs_utf2nls(struct super_block *sb, const char *in,
508 	     int in_len, char **out, int *out_len)
509 {
510 	struct nls_table *nls = BEFS_SB(sb)->nls;
511 	int i, o;
512 	wchar_t uni;
513 	int unilen, utflen;
514 	char *result;
515 	int maxlen = in_len; /* The utf8->nls conversion can't make more chars */
516 
517 	befs_debug(sb, "---> utf2nls()");
518 
519 	if (!nls) {
520 		befs_error(sb, "befs_utf2nls called with no NLS table loaded");
521 		return -EINVAL;
522 	}
523 
524 	*out = result = kmalloc(maxlen, GFP_NOFS);
525 	if (!*out) {
526 		befs_error(sb, "befs_utf2nls() cannot allocate memory");
527 		*out_len = 0;
528 		return -ENOMEM;
529 	}
530 
531 	for (i = o = 0; i < in_len; i += utflen, o += unilen) {
532 
533 		/* convert from UTF-8 to Unicode */
534 		utflen = utf8_mbtowc(&uni, &in[i], in_len - i);
535 		if (utflen < 0) {
536 			goto conv_err;
537 		}
538 
539 		/* convert from Unicode to nls */
540 		unilen = nls->uni2char(uni, &result[o], in_len - o);
541 		if (unilen < 0) {
542 			goto conv_err;
543 		}
544 	}
545 	result[o] = '\0';
546 	*out_len = o;
547 
548 	befs_debug(sb, "<--- utf2nls()");
549 
550 	return o;
551 
552       conv_err:
553 	befs_error(sb, "Name using character set %s contains a character that "
554 		   "cannot be converted to unicode.", nls->charset);
555 	befs_debug(sb, "<--- utf2nls()");
556 	kfree(result);
557 	return -EILSEQ;
558 }
559 
560 /**
561  * befs_nls2utf - Convert NLS string to utf8 encodeing
562  * @sb: Superblock
563  * @src: Input string buffer in NLS format
564  * @srclen: Length of input string in bytes
565  * @dest: The output string in UTF-8 format
566  * @destlen: Length of the output buffer
567  *
568  * Converts input string @src, which is in the format of the loaded NLS map,
569  * into a utf8 string.
570  *
571  * The destination string @dest is allocated by this function and the caller is
572  * responsible for freeing it with kfree()
573  *
574  * On return, *@destlen is the length of @dest in bytes.
575  *
576  * On success, the return value is the number of utf8 characters written to
577  * the output buffer @dest.
578  *
579  * On Failure, a negative number coresponding to the error code is returned.
580  */
581 
582 static int
583 befs_nls2utf(struct super_block *sb, const char *in,
584 	     int in_len, char **out, int *out_len)
585 {
586 	struct nls_table *nls = BEFS_SB(sb)->nls;
587 	int i, o;
588 	wchar_t uni;
589 	int unilen, utflen;
590 	char *result;
591 	int maxlen = 3 * in_len;
592 
593 	befs_debug(sb, "---> nls2utf()\n");
594 
595 	if (!nls) {
596 		befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
597 		return -EINVAL;
598 	}
599 
600 	*out = result = kmalloc(maxlen, GFP_NOFS);
601 	if (!*out) {
602 		befs_error(sb, "befs_nls2utf() cannot allocate memory");
603 		*out_len = 0;
604 		return -ENOMEM;
605 	}
606 
607 	for (i = o = 0; i < in_len; i += unilen, o += utflen) {
608 
609 		/* convert from nls to unicode */
610 		unilen = nls->char2uni(&in[i], in_len - i, &uni);
611 		if (unilen < 0) {
612 			goto conv_err;
613 		}
614 
615 		/* convert from unicode to UTF-8 */
616 		utflen = utf8_wctomb(&result[o], uni, 3);
617 		if (utflen <= 0) {
618 			goto conv_err;
619 		}
620 	}
621 
622 	result[o] = '\0';
623 	*out_len = o;
624 
625 	befs_debug(sb, "<--- nls2utf()");
626 
627 	return i;
628 
629       conv_err:
630 	befs_error(sb, "Name using charecter set %s contains a charecter that "
631 		   "cannot be converted to unicode.", nls->charset);
632 	befs_debug(sb, "<--- nls2utf()");
633 	kfree(result);
634 	return -EILSEQ;
635 }
636 
637 /**
638  * Use the
639  *
640  */
641 enum {
642 	Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
643 };
644 
645 static match_table_t befs_tokens = {
646 	{Opt_uid, "uid=%d"},
647 	{Opt_gid, "gid=%d"},
648 	{Opt_charset, "iocharset=%s"},
649 	{Opt_debug, "debug"},
650 	{Opt_err, NULL}
651 };
652 
653 static int
654 parse_options(char *options, befs_mount_options * opts)
655 {
656 	char *p;
657 	substring_t args[MAX_OPT_ARGS];
658 	int option;
659 
660 	/* Initialize options */
661 	opts->uid = 0;
662 	opts->gid = 0;
663 	opts->use_uid = 0;
664 	opts->use_gid = 0;
665 	opts->iocharset = NULL;
666 	opts->debug = 0;
667 
668 	if (!options)
669 		return 1;
670 
671 	while ((p = strsep(&options, ",")) != NULL) {
672 		int token;
673 		if (!*p)
674 			continue;
675 
676 		token = match_token(p, befs_tokens, args);
677 		switch (token) {
678 		case Opt_uid:
679 			if (match_int(&args[0], &option))
680 				return 0;
681 			if (option < 0) {
682 				printk(KERN_ERR "BeFS: Invalid uid %d, "
683 						"using default\n", option);
684 				break;
685 			}
686 			opts->uid = option;
687 			opts->use_uid = 1;
688 			break;
689 		case Opt_gid:
690 			if (match_int(&args[0], &option))
691 				return 0;
692 			if (option < 0) {
693 				printk(KERN_ERR "BeFS: Invalid gid %d, "
694 						"using default\n", option);
695 				break;
696 			}
697 			opts->gid = option;
698 			opts->use_gid = 1;
699 			break;
700 		case Opt_charset:
701 			kfree(opts->iocharset);
702 			opts->iocharset = match_strdup(&args[0]);
703 			if (!opts->iocharset) {
704 				printk(KERN_ERR "BeFS: allocation failure for "
705 						"iocharset string\n");
706 				return 0;
707 			}
708 			break;
709 		case Opt_debug:
710 			opts->debug = 1;
711 			break;
712 		default:
713 			printk(KERN_ERR "BeFS: Unrecognized mount option \"%s\" "
714 					"or missing value\n", p);
715 			return 0;
716 		}
717 	}
718 	return 1;
719 }
720 
721 /* This function has the responsibiltiy of getting the
722  * filesystem ready for unmounting.
723  * Basicly, we free everything that we allocated in
724  * befs_read_inode
725  */
726 static void
727 befs_put_super(struct super_block *sb)
728 {
729 	kfree(BEFS_SB(sb)->mount_opts.iocharset);
730 	BEFS_SB(sb)->mount_opts.iocharset = NULL;
731 
732 	if (BEFS_SB(sb)->nls) {
733 		unload_nls(BEFS_SB(sb)->nls);
734 		BEFS_SB(sb)->nls = NULL;
735 	}
736 
737 	kfree(sb->s_fs_info);
738 	sb->s_fs_info = NULL;
739 	return;
740 }
741 
742 /* Allocate private field of the superblock, fill it.
743  *
744  * Finish filling the public superblock fields
745  * Make the root directory
746  * Load a set of NLS translations if needed.
747  */
748 static int
749 befs_fill_super(struct super_block *sb, void *data, int silent)
750 {
751 	struct buffer_head *bh;
752 	befs_sb_info *befs_sb;
753 	befs_super_block *disk_sb;
754 	struct inode *root;
755 
756 	const unsigned long sb_block = 0;
757 	const off_t x86_sb_off = 512;
758 
759 	sb->s_fs_info = kmalloc(sizeof (*befs_sb), GFP_KERNEL);
760 	if (sb->s_fs_info == NULL) {
761 		printk(KERN_ERR
762 		       "BeFS(%s): Unable to allocate memory for private "
763 		       "portion of superblock. Bailing.\n", sb->s_id);
764 		goto unaquire_none;
765 	}
766 	befs_sb = BEFS_SB(sb);
767 	memset(befs_sb, 0, sizeof(befs_sb_info));
768 
769 	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
770 		befs_error(sb, "cannot parse mount options");
771 		goto unaquire_priv_sbp;
772 	}
773 
774 	befs_debug(sb, "---> befs_fill_super()");
775 
776 #ifndef CONFIG_BEFS_RW
777 	if (!(sb->s_flags & MS_RDONLY)) {
778 		befs_warning(sb,
779 			     "No write support. Marking filesystem read-only");
780 		sb->s_flags |= MS_RDONLY;
781 	}
782 #endif				/* CONFIG_BEFS_RW */
783 
784 	/*
785 	 * Set dummy blocksize to read super block.
786 	 * Will be set to real fs blocksize later.
787 	 *
788 	 * Linux 2.4.10 and later refuse to read blocks smaller than
789 	 * the hardsect size for the device. But we also need to read at
790 	 * least 1k to get the second 512 bytes of the volume.
791 	 * -WD 10-26-01
792 	 */
793 	sb_min_blocksize(sb, 1024);
794 
795 	if (!(bh = sb_bread(sb, sb_block))) {
796 		befs_error(sb, "unable to read superblock");
797 		goto unaquire_priv_sbp;
798 	}
799 
800 	/* account for offset of super block on x86 */
801 	disk_sb = (befs_super_block *) bh->b_data;
802 	if ((le32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1) ||
803 	    (be32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1)) {
804 		befs_debug(sb, "Using PPC superblock location");
805 	} else {
806 		befs_debug(sb, "Using x86 superblock location");
807 		disk_sb =
808 		    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
809 	}
810 
811 	if (befs_load_sb(sb, disk_sb) != BEFS_OK)
812 		goto unaquire_bh;
813 
814 	befs_dump_super_block(sb, disk_sb);
815 
816 	brelse(bh);
817 
818 	if (befs_check_sb(sb) != BEFS_OK)
819 		goto unaquire_priv_sbp;
820 
821 	if( befs_sb->num_blocks > ~((sector_t)0) ) {
822 		befs_error(sb, "blocks count: %Lu "
823 			"is larger than the host can use",
824 			befs_sb->num_blocks);
825 		goto unaquire_priv_sbp;
826 	}
827 
828 	/*
829 	 * set up enough so that it can read an inode
830 	 * Fill in kernel superblock fields from private sb
831 	 */
832 	sb->s_magic = BEFS_SUPER_MAGIC;
833 	/* Set real blocksize of fs */
834 	sb_set_blocksize(sb, (ulong) befs_sb->block_size);
835 	sb->s_op = (struct super_operations *) &befs_sops;
836 	root = iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
837 	sb->s_root = d_alloc_root(root);
838 	if (!sb->s_root) {
839 		iput(root);
840 		befs_error(sb, "get root inode failed");
841 		goto unaquire_priv_sbp;
842 	}
843 
844 	/* load nls library */
845 	if (befs_sb->mount_opts.iocharset) {
846 		befs_debug(sb, "Loading nls: %s",
847 			   befs_sb->mount_opts.iocharset);
848 		befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
849 		if (!befs_sb->nls) {
850 			befs_warning(sb, "Cannot load nls %s"
851 					" loading default nls",
852 					befs_sb->mount_opts.iocharset);
853 			befs_sb->nls = load_nls_default();
854 		}
855 	/* load default nls if none is specified  in mount options */
856 	} else {
857 		befs_debug(sb, "Loading default nls");
858 		befs_sb->nls = load_nls_default();
859 	}
860 
861 	return 0;
862 /*****************/
863       unaquire_bh:
864 	brelse(bh);
865 
866       unaquire_priv_sbp:
867 	kfree(sb->s_fs_info);
868 
869       unaquire_none:
870 	sb->s_fs_info = NULL;
871 	return -EINVAL;
872 }
873 
874 static int
875 befs_remount(struct super_block *sb, int *flags, char *data)
876 {
877 	if (!(*flags & MS_RDONLY))
878 		return -EINVAL;
879 	return 0;
880 }
881 
882 static int
883 befs_statfs(struct super_block *sb, struct kstatfs *buf)
884 {
885 
886 	befs_debug(sb, "---> befs_statfs()");
887 
888 	buf->f_type = BEFS_SUPER_MAGIC;
889 	buf->f_bsize = sb->s_blocksize;
890 	buf->f_blocks = BEFS_SB(sb)->num_blocks;
891 	buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
892 	buf->f_bavail = buf->f_bfree;
893 	buf->f_files = 0;	/* UNKNOWN */
894 	buf->f_ffree = 0;	/* UNKNOWN */
895 	buf->f_namelen = BEFS_NAME_LEN;
896 
897 	befs_debug(sb, "<--- befs_statfs()");
898 
899 	return 0;
900 }
901 
902 static struct super_block *
903 befs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name,
904 	    void *data)
905 {
906 	return get_sb_bdev(fs_type, flags, dev_name, data, befs_fill_super);
907 }
908 
909 static struct file_system_type befs_fs_type = {
910 	.owner		= THIS_MODULE,
911 	.name		= "befs",
912 	.get_sb		= befs_get_sb,
913 	.kill_sb	= kill_block_super,
914 	.fs_flags	= FS_REQUIRES_DEV,
915 };
916 
917 static int __init
918 init_befs_fs(void)
919 {
920 	int err;
921 
922 	printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
923 
924 	err = befs_init_inodecache();
925 	if (err)
926 		goto unaquire_none;
927 
928 	err = register_filesystem(&befs_fs_type);
929 	if (err)
930 		goto unaquire_inodecache;
931 
932 	return 0;
933 
934 unaquire_inodecache:
935 	befs_destroy_inodecache();
936 
937 unaquire_none:
938 	return err;
939 }
940 
941 static void __exit
942 exit_befs_fs(void)
943 {
944 	befs_destroy_inodecache();
945 
946 	unregister_filesystem(&befs_fs_type);
947 }
948 
949 /*
950 Macros that typecheck the init and exit functions,
951 ensures that they are called at init and cleanup,
952 and eliminates warnings about unused functions.
953 */
954 module_init(init_befs_fs)
955 module_exit(exit_befs_fs)
956