xref: /openbmc/linux/fs/befs/linuxvfs.c (revision 93dc544c)
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 
26 MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
27 MODULE_AUTHOR("Will Dyson");
28 MODULE_LICENSE("GPL");
29 
30 /* The units the vfs expects inode->i_blocks to be in */
31 #define VFS_BLOCK_SIZE 512
32 
33 static int befs_readdir(struct file *, void *, filldir_t);
34 static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
35 static int befs_readpage(struct file *file, struct page *page);
36 static sector_t befs_bmap(struct address_space *mapping, sector_t block);
37 static struct dentry *befs_lookup(struct inode *, struct dentry *, struct nameidata *);
38 static struct inode *befs_iget(struct super_block *, unsigned long);
39 static struct inode *befs_alloc_inode(struct super_block *sb);
40 static void befs_destroy_inode(struct inode *inode);
41 static int befs_init_inodecache(void);
42 static void befs_destroy_inodecache(void);
43 static void *befs_follow_link(struct dentry *, struct nameidata *);
44 static void befs_put_link(struct dentry *, struct nameidata *, void *);
45 static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
46 			char **out, int *out_len);
47 static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
48 			char **out, int *out_len);
49 static void befs_put_super(struct super_block *);
50 static int befs_remount(struct super_block *, int *, char *);
51 static int befs_statfs(struct dentry *, struct kstatfs *);
52 static int parse_options(char *, befs_mount_options *);
53 
54 static 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 */
64 static struct kmem_cache *befs_inode_cachep;
65 
66 static const struct file_operations befs_dir_operations = {
67 	.read		= generic_read_dir,
68 	.readdir	= befs_readdir,
69 };
70 
71 static const struct inode_operations befs_dir_inode_operations = {
72 	.lookup		= befs_lookup,
73 };
74 
75 static const struct address_space_operations befs_aops = {
76 	.readpage	= befs_readpage,
77 	.sync_page	= block_sync_page,
78 	.bmap		= befs_bmap,
79 };
80 
81 static 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  */
94 static int
95 befs_readpage(struct file *file, struct page *page)
96 {
97 	return block_read_full_page(page, befs_get_block);
98 }
99 
100 static sector_t
101 befs_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 
117 static int
118 befs_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 
161 static struct dentry *
162 befs_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 
212 static int
213 befs_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 
275 static struct inode *
276 befs_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 
286 static void
287 befs_destroy_inode(struct inode *inode)
288 {
289         kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
290 }
291 
292 static void init_once(void *foo)
293 {
294         struct befs_inode_info *bi = (struct befs_inode_info *) foo;
295 
296 	inode_init_once(&bi->vfs_inode);
297 }
298 
299 static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
300 {
301 	struct buffer_head *bh = NULL;
302 	befs_inode *raw_inode = NULL;
303 
304 	befs_sb_info *befs_sb = BEFS_SB(sb);
305 	befs_inode_info *befs_ino = NULL;
306 	struct inode *inode;
307 	long ret = -EIO;
308 
309 	befs_debug(sb, "---> befs_read_inode() " "inode = %lu", ino);
310 
311 	inode = iget_locked(sb, ino);
312 	if (IS_ERR(inode))
313 		return inode;
314 	if (!(inode->i_state & I_NEW))
315 		return inode;
316 
317 	befs_ino = BEFS_I(inode);
318 
319 	/* convert from vfs's inode number to befs's inode number */
320 	befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
321 
322 	befs_debug(sb, "  real inode number [%u, %hu, %hu]",
323 		   befs_ino->i_inode_num.allocation_group,
324 		   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
325 
326 	bh = befs_bread(sb, inode->i_ino);
327 	if (!bh) {
328 		befs_error(sb, "unable to read inode block - "
329 			   "inode = %lu", inode->i_ino);
330 		goto unacquire_none;
331 	}
332 
333 	raw_inode = (befs_inode *) bh->b_data;
334 
335 	befs_dump_inode(sb, raw_inode);
336 
337 	if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
338 		befs_error(sb, "Bad inode: %lu", inode->i_ino);
339 		goto unacquire_bh;
340 	}
341 
342 	inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
343 
344 	/*
345 	 * set uid and gid.  But since current BeOS is single user OS, so
346 	 * you can change by "uid" or "gid" options.
347 	 */
348 
349 	inode->i_uid = befs_sb->mount_opts.use_uid ?
350 	    befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
351 	inode->i_gid = befs_sb->mount_opts.use_gid ?
352 	    befs_sb->mount_opts.gid : (gid_t) fs32_to_cpu(sb, raw_inode->gid);
353 
354 	inode->i_nlink = 1;
355 
356 	/*
357 	 * BEFS's time is 64 bits, but current VFS is 32 bits...
358 	 * BEFS don't have access time. Nor inode change time. VFS
359 	 * doesn't have creation time.
360 	 * Also, the lower 16 bits of the last_modified_time and
361 	 * create_time are just a counter to help ensure uniqueness
362 	 * for indexing purposes. (PFD, page 54)
363 	 */
364 
365 	inode->i_mtime.tv_sec =
366 	    fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
367 	inode->i_mtime.tv_nsec = 0;   /* lower 16 bits are not a time */
368 	inode->i_ctime = inode->i_mtime;
369 	inode->i_atime = inode->i_mtime;
370 
371 	befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
372 	befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
373 	befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
374 	befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
375 
376 	if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
377 		inode->i_size = 0;
378 		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
379 		strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
380 			BEFS_SYMLINK_LEN);
381 	} else {
382 		int num_blks;
383 
384 		befs_ino->i_data.ds =
385 		    fsds_to_cpu(sb, raw_inode->data.datastream);
386 
387 		num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
388 		inode->i_blocks =
389 		    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
390 		inode->i_size = befs_ino->i_data.ds.size;
391 	}
392 
393 	inode->i_mapping->a_ops = &befs_aops;
394 
395 	if (S_ISREG(inode->i_mode)) {
396 		inode->i_fop = &generic_ro_fops;
397 	} else if (S_ISDIR(inode->i_mode)) {
398 		inode->i_op = &befs_dir_inode_operations;
399 		inode->i_fop = &befs_dir_operations;
400 	} else if (S_ISLNK(inode->i_mode)) {
401 		inode->i_op = &befs_symlink_inode_operations;
402 	} else {
403 		befs_error(sb, "Inode %lu is not a regular file, "
404 			   "directory or symlink. THAT IS WRONG! BeFS has no "
405 			   "on disk special files", inode->i_ino);
406 		goto unacquire_bh;
407 	}
408 
409 	brelse(bh);
410 	befs_debug(sb, "<--- befs_read_inode()");
411 	unlock_new_inode(inode);
412 	return inode;
413 
414       unacquire_bh:
415 	brelse(bh);
416 
417       unacquire_none:
418 	iget_failed(inode);
419 	befs_debug(sb, "<--- befs_read_inode() - Bad inode");
420 	return ERR_PTR(ret);
421 }
422 
423 /* Initialize the inode cache. Called at fs setup.
424  *
425  * Taken from NFS implementation by Al Viro.
426  */
427 static int
428 befs_init_inodecache(void)
429 {
430 	befs_inode_cachep = kmem_cache_create("befs_inode_cache",
431 					      sizeof (struct befs_inode_info),
432 					      0, (SLAB_RECLAIM_ACCOUNT|
433 						SLAB_MEM_SPREAD),
434 					      init_once);
435 	if (befs_inode_cachep == NULL) {
436 		printk(KERN_ERR "befs_init_inodecache: "
437 		       "Couldn't initalize inode slabcache\n");
438 		return -ENOMEM;
439 	}
440 
441 	return 0;
442 }
443 
444 /* Called at fs teardown.
445  *
446  * Taken from NFS implementation by Al Viro.
447  */
448 static void
449 befs_destroy_inodecache(void)
450 {
451 	kmem_cache_destroy(befs_inode_cachep);
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 *link = nd_get_link(nd);
493 		if (!IS_ERR(link))
494 			kfree(link);
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 	/* The utf8->nls conversion won't make the final nls string bigger
516 	 * than the utf one, but if the string is pure ascii they'll have the
517 	 * same width and an extra char is needed to save the additional \0
518 	 */
519 	int maxlen = in_len + 1;
520 
521 	befs_debug(sb, "---> utf2nls()");
522 
523 	if (!nls) {
524 		befs_error(sb, "befs_utf2nls called with no NLS table loaded");
525 		return -EINVAL;
526 	}
527 
528 	*out = result = kmalloc(maxlen, GFP_NOFS);
529 	if (!*out) {
530 		befs_error(sb, "befs_utf2nls() cannot allocate memory");
531 		*out_len = 0;
532 		return -ENOMEM;
533 	}
534 
535 	for (i = o = 0; i < in_len; i += utflen, o += unilen) {
536 
537 		/* convert from UTF-8 to Unicode */
538 		utflen = utf8_mbtowc(&uni, &in[i], in_len - i);
539 		if (utflen < 0) {
540 			goto conv_err;
541 		}
542 
543 		/* convert from Unicode to nls */
544 		unilen = nls->uni2char(uni, &result[o], in_len - o);
545 		if (unilen < 0) {
546 			goto conv_err;
547 		}
548 	}
549 	result[o] = '\0';
550 	*out_len = o;
551 
552 	befs_debug(sb, "<--- utf2nls()");
553 
554 	return o;
555 
556       conv_err:
557 	befs_error(sb, "Name using character set %s contains a character that "
558 		   "cannot be converted to unicode.", nls->charset);
559 	befs_debug(sb, "<--- utf2nls()");
560 	kfree(result);
561 	return -EILSEQ;
562 }
563 
564 /**
565  * befs_nls2utf - Convert NLS string to utf8 encodeing
566  * @sb: Superblock
567  * @src: Input string buffer in NLS format
568  * @srclen: Length of input string in bytes
569  * @dest: The output string in UTF-8 format
570  * @destlen: Length of the output buffer
571  *
572  * Converts input string @src, which is in the format of the loaded NLS map,
573  * into a utf8 string.
574  *
575  * The destination string @dest is allocated by this function and the caller is
576  * responsible for freeing it with kfree()
577  *
578  * On return, *@destlen is the length of @dest in bytes.
579  *
580  * On success, the return value is the number of utf8 characters written to
581  * the output buffer @dest.
582  *
583  * On Failure, a negative number coresponding to the error code is returned.
584  */
585 
586 static int
587 befs_nls2utf(struct super_block *sb, const char *in,
588 	     int in_len, char **out, int *out_len)
589 {
590 	struct nls_table *nls = BEFS_SB(sb)->nls;
591 	int i, o;
592 	wchar_t uni;
593 	int unilen, utflen;
594 	char *result;
595 	/* There're nls characters that will translate to 3-chars-wide UTF-8
596 	 * characters, a additional byte is needed to save the final \0
597 	 * in special cases */
598 	int maxlen = (3 * in_len) + 1;
599 
600 	befs_debug(sb, "---> nls2utf()\n");
601 
602 	if (!nls) {
603 		befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
604 		return -EINVAL;
605 	}
606 
607 	*out = result = kmalloc(maxlen, GFP_NOFS);
608 	if (!*out) {
609 		befs_error(sb, "befs_nls2utf() cannot allocate memory");
610 		*out_len = 0;
611 		return -ENOMEM;
612 	}
613 
614 	for (i = o = 0; i < in_len; i += unilen, o += utflen) {
615 
616 		/* convert from nls to unicode */
617 		unilen = nls->char2uni(&in[i], in_len - i, &uni);
618 		if (unilen < 0) {
619 			goto conv_err;
620 		}
621 
622 		/* convert from unicode to UTF-8 */
623 		utflen = utf8_wctomb(&result[o], uni, 3);
624 		if (utflen <= 0) {
625 			goto conv_err;
626 		}
627 	}
628 
629 	result[o] = '\0';
630 	*out_len = o;
631 
632 	befs_debug(sb, "<--- nls2utf()");
633 
634 	return i;
635 
636       conv_err:
637 	befs_error(sb, "Name using charecter set %s contains a charecter that "
638 		   "cannot be converted to unicode.", nls->charset);
639 	befs_debug(sb, "<--- nls2utf()");
640 	kfree(result);
641 	return -EILSEQ;
642 }
643 
644 /**
645  * Use the
646  *
647  */
648 enum {
649 	Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
650 };
651 
652 static match_table_t befs_tokens = {
653 	{Opt_uid, "uid=%d"},
654 	{Opt_gid, "gid=%d"},
655 	{Opt_charset, "iocharset=%s"},
656 	{Opt_debug, "debug"},
657 	{Opt_err, NULL}
658 };
659 
660 static int
661 parse_options(char *options, befs_mount_options * opts)
662 {
663 	char *p;
664 	substring_t args[MAX_OPT_ARGS];
665 	int option;
666 
667 	/* Initialize options */
668 	opts->uid = 0;
669 	opts->gid = 0;
670 	opts->use_uid = 0;
671 	opts->use_gid = 0;
672 	opts->iocharset = NULL;
673 	opts->debug = 0;
674 
675 	if (!options)
676 		return 1;
677 
678 	while ((p = strsep(&options, ",")) != NULL) {
679 		int token;
680 		if (!*p)
681 			continue;
682 
683 		token = match_token(p, befs_tokens, args);
684 		switch (token) {
685 		case Opt_uid:
686 			if (match_int(&args[0], &option))
687 				return 0;
688 			if (option < 0) {
689 				printk(KERN_ERR "BeFS: Invalid uid %d, "
690 						"using default\n", option);
691 				break;
692 			}
693 			opts->uid = option;
694 			opts->use_uid = 1;
695 			break;
696 		case Opt_gid:
697 			if (match_int(&args[0], &option))
698 				return 0;
699 			if (option < 0) {
700 				printk(KERN_ERR "BeFS: Invalid gid %d, "
701 						"using default\n", option);
702 				break;
703 			}
704 			opts->gid = option;
705 			opts->use_gid = 1;
706 			break;
707 		case Opt_charset:
708 			kfree(opts->iocharset);
709 			opts->iocharset = match_strdup(&args[0]);
710 			if (!opts->iocharset) {
711 				printk(KERN_ERR "BeFS: allocation failure for "
712 						"iocharset string\n");
713 				return 0;
714 			}
715 			break;
716 		case Opt_debug:
717 			opts->debug = 1;
718 			break;
719 		default:
720 			printk(KERN_ERR "BeFS: Unrecognized mount option \"%s\" "
721 					"or missing value\n", p);
722 			return 0;
723 		}
724 	}
725 	return 1;
726 }
727 
728 /* This function has the responsibiltiy of getting the
729  * filesystem ready for unmounting.
730  * Basicly, we free everything that we allocated in
731  * befs_read_inode
732  */
733 static void
734 befs_put_super(struct super_block *sb)
735 {
736 	kfree(BEFS_SB(sb)->mount_opts.iocharset);
737 	BEFS_SB(sb)->mount_opts.iocharset = NULL;
738 
739 	if (BEFS_SB(sb)->nls) {
740 		unload_nls(BEFS_SB(sb)->nls);
741 		BEFS_SB(sb)->nls = NULL;
742 	}
743 
744 	kfree(sb->s_fs_info);
745 	sb->s_fs_info = NULL;
746 	return;
747 }
748 
749 /* Allocate private field of the superblock, fill it.
750  *
751  * Finish filling the public superblock fields
752  * Make the root directory
753  * Load a set of NLS translations if needed.
754  */
755 static int
756 befs_fill_super(struct super_block *sb, void *data, int silent)
757 {
758 	struct buffer_head *bh;
759 	befs_sb_info *befs_sb;
760 	befs_super_block *disk_sb;
761 	struct inode *root;
762 	long ret = -EINVAL;
763 	const unsigned long sb_block = 0;
764 	const off_t x86_sb_off = 512;
765 
766 	save_mount_options(sb, data);
767 
768 	sb->s_fs_info = kmalloc(sizeof (*befs_sb), GFP_KERNEL);
769 	if (sb->s_fs_info == NULL) {
770 		printk(KERN_ERR
771 		       "BeFS(%s): Unable to allocate memory for private "
772 		       "portion of superblock. Bailing.\n", sb->s_id);
773 		goto unacquire_none;
774 	}
775 	befs_sb = BEFS_SB(sb);
776 	memset(befs_sb, 0, sizeof(befs_sb_info));
777 
778 	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
779 		befs_error(sb, "cannot parse mount options");
780 		goto unacquire_priv_sbp;
781 	}
782 
783 	befs_debug(sb, "---> befs_fill_super()");
784 
785 #ifndef CONFIG_BEFS_RW
786 	if (!(sb->s_flags & MS_RDONLY)) {
787 		befs_warning(sb,
788 			     "No write support. Marking filesystem read-only");
789 		sb->s_flags |= MS_RDONLY;
790 	}
791 #endif				/* CONFIG_BEFS_RW */
792 
793 	/*
794 	 * Set dummy blocksize to read super block.
795 	 * Will be set to real fs blocksize later.
796 	 *
797 	 * Linux 2.4.10 and later refuse to read blocks smaller than
798 	 * the hardsect size for the device. But we also need to read at
799 	 * least 1k to get the second 512 bytes of the volume.
800 	 * -WD 10-26-01
801 	 */
802 	sb_min_blocksize(sb, 1024);
803 
804 	if (!(bh = sb_bread(sb, sb_block))) {
805 		befs_error(sb, "unable to read superblock");
806 		goto unacquire_priv_sbp;
807 	}
808 
809 	/* account for offset of super block on x86 */
810 	disk_sb = (befs_super_block *) bh->b_data;
811 	if ((le32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1) ||
812 	    (be32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1)) {
813 		befs_debug(sb, "Using PPC superblock location");
814 	} else {
815 		befs_debug(sb, "Using x86 superblock location");
816 		disk_sb =
817 		    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
818 	}
819 
820 	if (befs_load_sb(sb, disk_sb) != BEFS_OK)
821 		goto unacquire_bh;
822 
823 	befs_dump_super_block(sb, disk_sb);
824 
825 	brelse(bh);
826 
827 	if (befs_check_sb(sb) != BEFS_OK)
828 		goto unacquire_priv_sbp;
829 
830 	if( befs_sb->num_blocks > ~((sector_t)0) ) {
831 		befs_error(sb, "blocks count: %Lu "
832 			"is larger than the host can use",
833 			befs_sb->num_blocks);
834 		goto unacquire_priv_sbp;
835 	}
836 
837 	/*
838 	 * set up enough so that it can read an inode
839 	 * Fill in kernel superblock fields from private sb
840 	 */
841 	sb->s_magic = BEFS_SUPER_MAGIC;
842 	/* Set real blocksize of fs */
843 	sb_set_blocksize(sb, (ulong) befs_sb->block_size);
844 	sb->s_op = (struct super_operations *) &befs_sops;
845 	root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
846 	if (IS_ERR(root)) {
847 		ret = PTR_ERR(root);
848 		goto unacquire_priv_sbp;
849 	}
850 	sb->s_root = d_alloc_root(root);
851 	if (!sb->s_root) {
852 		iput(root);
853 		befs_error(sb, "get root inode failed");
854 		goto unacquire_priv_sbp;
855 	}
856 
857 	/* load nls library */
858 	if (befs_sb->mount_opts.iocharset) {
859 		befs_debug(sb, "Loading nls: %s",
860 			   befs_sb->mount_opts.iocharset);
861 		befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
862 		if (!befs_sb->nls) {
863 			befs_warning(sb, "Cannot load nls %s"
864 					" loading default nls",
865 					befs_sb->mount_opts.iocharset);
866 			befs_sb->nls = load_nls_default();
867 		}
868 	/* load default nls if none is specified  in mount options */
869 	} else {
870 		befs_debug(sb, "Loading default nls");
871 		befs_sb->nls = load_nls_default();
872 	}
873 
874 	return 0;
875 /*****************/
876       unacquire_bh:
877 	brelse(bh);
878 
879       unacquire_priv_sbp:
880 	kfree(sb->s_fs_info);
881 
882       unacquire_none:
883 	sb->s_fs_info = NULL;
884 	return ret;
885 }
886 
887 static int
888 befs_remount(struct super_block *sb, int *flags, char *data)
889 {
890 	if (!(*flags & MS_RDONLY))
891 		return -EINVAL;
892 	return 0;
893 }
894 
895 static int
896 befs_statfs(struct dentry *dentry, struct kstatfs *buf)
897 {
898 	struct super_block *sb = dentry->d_sb;
899 
900 	befs_debug(sb, "---> befs_statfs()");
901 
902 	buf->f_type = BEFS_SUPER_MAGIC;
903 	buf->f_bsize = sb->s_blocksize;
904 	buf->f_blocks = BEFS_SB(sb)->num_blocks;
905 	buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
906 	buf->f_bavail = buf->f_bfree;
907 	buf->f_files = 0;	/* UNKNOWN */
908 	buf->f_ffree = 0;	/* UNKNOWN */
909 	buf->f_namelen = BEFS_NAME_LEN;
910 
911 	befs_debug(sb, "<--- befs_statfs()");
912 
913 	return 0;
914 }
915 
916 static int
917 befs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name,
918 	    void *data, struct vfsmount *mnt)
919 {
920 	return get_sb_bdev(fs_type, flags, dev_name, data, befs_fill_super,
921 			   mnt);
922 }
923 
924 static struct file_system_type befs_fs_type = {
925 	.owner		= THIS_MODULE,
926 	.name		= "befs",
927 	.get_sb		= befs_get_sb,
928 	.kill_sb	= kill_block_super,
929 	.fs_flags	= FS_REQUIRES_DEV,
930 };
931 
932 static int __init
933 init_befs_fs(void)
934 {
935 	int err;
936 
937 	printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
938 
939 	err = befs_init_inodecache();
940 	if (err)
941 		goto unacquire_none;
942 
943 	err = register_filesystem(&befs_fs_type);
944 	if (err)
945 		goto unacquire_inodecache;
946 
947 	return 0;
948 
949 unacquire_inodecache:
950 	befs_destroy_inodecache();
951 
952 unacquire_none:
953 	return err;
954 }
955 
956 static void __exit
957 exit_befs_fs(void)
958 {
959 	befs_destroy_inodecache();
960 
961 	unregister_filesystem(&befs_fs_type);
962 }
963 
964 /*
965 Macros that typecheck the init and exit functions,
966 ensures that they are called at init and cleanup,
967 and eliminates warnings about unused functions.
968 */
969 module_init(init_befs_fs)
970 module_exit(exit_befs_fs)
971