1 /*
2  * linux/fs/befs/linuxvfs.c
3  *
4  * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
5  *
6  */
7 
8 #include <linux/blkdev.h>
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/errno.h>
13 #include <linux/fs.h>
14 #include <linux/stat.h>
15 #include <linux/string.h>
16 #include <linux/nls.h>
17 
18 #include "befs.h"
19 #include "btree.h"
20 #include "inode.h"
21 #include "datastream.h"
22 #include "super.h"
23 #include "io.h"
24 #include "endian.h"
25 
26 EXPORT_NO_SYMBOLS;
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 *, long, struct buffer_head *, int);
36 static int befs_readpage(struct file *file, struct page *page);
37 static int befs_bmap(struct address_space *mapping, long block);
38 static struct dentry *befs_lookup(struct inode *, struct dentry *);
39 static void befs_read_inode(struct inode *ino);
40 static void befs_clear_inode(struct inode *ino);
41 static int befs_init_inodecache(void);
42 static void befs_destroy_inodecache(void);
43 
44 static int befs_readlink(struct dentry *, char *, int);
45 static int befs_follow_link(struct dentry *, struct nameidata *nd);
46 
47 static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
48 			char **out, int *out_len);
49 static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
50 			char **out, int *out_len);
51 
52 static void befs_put_super(struct super_block *);
53 static struct super_block *befs_read_super(struct super_block *, void *, int);
54 static int befs_remount(struct super_block *, int *, char *);
55 static int befs_statfs(struct super_block *, struct statfs *);
56 static int parse_options(char *, befs_mount_options *);
57 
58 /* slab cache for befs_inode_info objects */
59 static kmem_cache_t *befs_inode_cachep;
60 
61 static const struct super_operations befs_sops = {
62 	read_inode:befs_read_inode,	/* initialize & read inode */
63 	clear_inode:befs_clear_inode,	/* uninit inode */
64 	put_super:befs_put_super,	/* uninit super */
65 	statfs:befs_statfs,	/* statfs */
66 	remount_fs:befs_remount,
67 };
68 
69 struct file_operations befs_dir_operations = {
70 	read:generic_read_dir,
71 	readdir:befs_readdir,
72 };
73 
74 struct inode_operations befs_dir_inode_operations = {
75 	lookup:befs_lookup,
76 };
77 
78 struct file_operations befs_file_operations = {
79 	llseek:default_llseek,
80 	read:generic_file_read,
81 	mmap:generic_file_mmap,
82 };
83 
84 struct inode_operations befs_file_inode_operations = {
85 };
86 
87 struct address_space_operations befs_aops = {
88 	readpage:befs_readpage,
89 	sync_page:block_sync_page,
90 	bmap:befs_bmap,
91 };
92 
93 static struct inode_operations befs_symlink_inode_operations = {
94 	readlink:befs_readlink,
95 	follow_link:befs_follow_link,
96 };
97 
98 /*
99  * Called by generic_file_read() to read a page of data
100  *
101  * In turn, simply calls a generic block read function and
102  * passes it the address of befs_get_block, for mapping file
103  * positions to disk blocks.
104  */
105 static int
befs_readpage(struct file * file,struct page * page)106 befs_readpage(struct file *file, struct page *page)
107 {
108 	return block_read_full_page(page, befs_get_block);
109 }
110 
111 static int
befs_bmap(struct address_space * mapping,long block)112 befs_bmap(struct address_space *mapping, long block)
113 {
114 	return generic_block_bmap(mapping, block, befs_get_block);
115 }
116 
117 /*
118  * Generic function to map a file position (block) to a
119  * disk offset (passed back in bh_result).
120  *
121  * Used by many higher level functions.
122  *
123  * Calls befs_fblock2brun() in datastream.c to do the real work.
124  *
125  * -WD 10-26-01
126  */
127 
128 static int
befs_get_block(struct inode * inode,long block,struct buffer_head * bh_result,int create)129 befs_get_block(struct inode *inode, long block,
130 	       struct buffer_head *bh_result, int create)
131 {
132 	struct super_block *sb = inode->i_sb;
133 	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
134 	befs_block_run run = BAD_IADDR;
135 	int res = 0;
136 	ulong disk_off;
137 
138 	befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
139 		   inode->i_ino, block);
140 
141 	if (block < 0) {
142 		befs_error(sb, "befs_get_block() was asked for a block "
143 			   "number less than zero: block %ld in inode %lu",
144 			   block, inode->i_ino);
145 		return -EIO;
146 	}
147 
148 	if (create) {
149 		befs_error(sb, "befs_get_block() was asked to write to "
150 			   "block %ld in inode %lu", block, inode->i_ino);
151 		return -EPERM;
152 	}
153 
154 	res = befs_fblock2brun(sb, ds, block, &run);
155 	if (res != BEFS_OK) {
156 		befs_error(sb,
157 			   "<--- befs_get_block() for inode %lu, block "
158 			   "%ld ERROR", inode->i_ino, block);
159 		return -EFBIG;
160 	}
161 
162 	disk_off = (ulong) iaddr2blockno(sb, &run);
163 
164 	bh_result->b_dev = inode->i_dev;
165 	bh_result->b_blocknr = disk_off;
166 	bh_result->b_state |= (1UL << BH_Mapped);
167 
168 	befs_debug(sb, "<--- befs_get_block() for inode %lu, block %ld, "
169 		   "disk address %lu", inode->i_ino, block, disk_off);
170 
171 	return 0;
172 }
173 
174 static struct dentry *
befs_lookup(struct inode * dir,struct dentry * dentry)175 befs_lookup(struct inode *dir, struct dentry *dentry)
176 {
177 	struct inode *inode = NULL;
178 	struct super_block *sb = dir->i_sb;
179 	befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
180 	befs_off_t offset;
181 	int ret;
182 	int utfnamelen;
183 	char *utfname;
184 	const char *name = dentry->d_name.name;
185 
186 	befs_debug(sb, "---> befs_lookup() "
187 		   "name %s inode %ld", dentry->d_name.name, dir->i_ino);
188 
189 	/* Convert to UTF-8 */
190 	if (BEFS_SB(sb)->nls) {
191 		ret =
192 		    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
193 		if (ret < 0) {
194 			befs_debug(sb, "<--- befs_lookup() ERROR");
195 			return ERR_PTR(ret);
196 		}
197 		ret = befs_btree_find(sb, ds, utfname, &offset);
198 		kfree(utfname);
199 
200 	} else {
201 		ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
202 	}
203 
204 	if (ret == BEFS_BT_NOT_FOUND) {
205 		befs_debug(sb, "<--- befs_lookup() %s not found",
206 			   dentry->d_name.name);
207 		return ERR_PTR(-ENOENT);
208 
209 	} else if (ret != BEFS_OK || offset == 0) {
210 		befs_warning(sb, "<--- befs_lookup() Error");
211 		return ERR_PTR(-ENODATA);
212 	}
213 
214 	inode = iget(dir->i_sb, (ino_t) offset);
215 	if (!inode)
216 		return ERR_PTR(-EACCES);
217 
218 	d_add(dentry, inode);
219 
220 	befs_debug(sb, "<--- befs_lookup()");
221 
222 	return NULL;
223 }
224 
225 static int
befs_readdir(struct file * filp,void * dirent,filldir_t filldir)226 befs_readdir(struct file *filp, void *dirent, filldir_t filldir)
227 {
228 	struct inode *inode = filp->f_dentry->d_inode;
229 	struct super_block *sb = inode->i_sb;
230 	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
231 	befs_off_t value;
232 	int result;
233 	size_t keysize;
234 	unsigned char d_type;
235 	char keybuf[BEFS_NAME_LEN + 1];
236 	char *nlsname;
237 	int nlsnamelen;
238 	const char *dirname = filp->f_dentry->d_name.name;
239 
240 	befs_debug(sb, "---> befs_readdir() "
241 		   "name %s, inode %ld, filp->f_pos %Ld",
242 		   dirname, inode->i_ino, filp->f_pos);
243 
244 	result = befs_btree_read(sb, ds, filp->f_pos, BEFS_NAME_LEN + 1,
245 				 keybuf, &keysize, &value);
246 
247 	if (result == BEFS_ERR) {
248 		befs_debug(sb, "<--- befs_readdir() ERROR");
249 		befs_error(sb, "IO error reading %s (inode %lu)",
250 			   dirname, inode->i_ino);
251 		return -EIO;
252 
253 	} else if (result == BEFS_BT_END) {
254 		befs_debug(sb, "<--- befs_readdir() END");
255 		return 0;
256 
257 	} else if (result == BEFS_BT_EMPTY) {
258 		befs_debug(sb, "<--- befs_readdir() Empty directory");
259 		return 0;
260 	}
261 
262 	d_type = DT_UNKNOWN;
263 
264 	/* Convert to NLS */
265 	if (BEFS_SB(sb)->nls) {
266 		result =
267 		    befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
268 		if (result < 0) {
269 			befs_debug(sb, "<--- befs_readdir() ERROR");
270 			return result;
271 		}
272 		result = filldir(dirent, nlsname, nlsnamelen, filp->f_pos,
273 				 (ino_t) value, d_type);
274 		kfree(nlsname);
275 
276 	} else {
277 		result = filldir(dirent, keybuf, keysize, filp->f_pos,
278 				 (ino_t) value, d_type);
279 	}
280 
281 	filp->f_pos++;
282 
283 	befs_debug(sb, "<--- befs_readdir() filp->f_pos %Ld", filp->f_pos);
284 
285 	return 0;
286 }
287 
288 static void
befs_clear_inode(struct inode * inode)289 befs_clear_inode(struct inode *inode)
290 {
291 	befs_inode_info *b_ino = BEFS_I(inode);
292 	inode->u.generic_ip = NULL;
293 
294 	if (b_ino) {
295 		kmem_cache_free(befs_inode_cachep, b_ino);
296 	}
297 	return;
298 }
299 
300 static void
befs_read_inode(struct inode * inode)301 befs_read_inode(struct inode *inode)
302 {
303 	struct buffer_head *bh = NULL;
304 	befs_inode *raw_inode = NULL;
305 
306 	struct super_block *sb = inode->i_sb;
307 	befs_sb_info *befs_sb = BEFS_SB(sb);
308 	befs_inode_info *befs_ino = NULL;
309 
310 	befs_debug(sb, "---> befs_read_inode() " "inode = %lu", inode->i_ino);
311 
312 	inode->u.generic_ip = kmem_cache_alloc(befs_inode_cachep, GFP_NOFS);
313 	if (inode->u.generic_ip == NULL) {
314 		befs_error(sb, "Unable to allocate memory for private "
315 			   "portion of inode %lu.", inode->i_ino);
316 		goto unaquire_none;
317 	}
318 	befs_ino = BEFS_I(inode);
319 
320 	/* convert from vfs's inode number to befs's inode number */
321 	befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
322 
323 	befs_debug(sb, "  real inode number [%u, %hu, %hu]",
324 		   befs_ino->i_inode_num.allocation_group,
325 		   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
326 
327 	bh = befs_bread_iaddr(sb, befs_ino->i_inode_num);
328 	if (!bh) {
329 		befs_error(sb, "unable to read inode block - "
330 			   "inode = %lu", inode->i_ino);
331 		goto unaquire_ino_info;
332 	}
333 
334 	raw_inode = (befs_inode *) bh->b_data;
335 
336 	befs_dump_inode(sb, raw_inode);
337 
338 	if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
339 		befs_error(sb, "Bad inode: %lu", inode->i_ino);
340 		goto unaquire_bh;
341 	}
342 
343 	inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
344 
345 	/*
346 	 * set uid and gid.  But since current BeOS is single user OS, so
347 	 * you can change by "uid" or "gid" options.
348 	 */
349 
350 	inode->i_uid = befs_sb->mount_opts.use_uid ?
351 	    befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
352 	inode->i_gid = befs_sb->mount_opts.use_gid ?
353 	    befs_sb->mount_opts.gid : (gid_t) fs32_to_cpu(sb, raw_inode->gid);
354 
355 	inode->i_nlink = 1;
356 
357 	/*
358 	 * BEFS's time is 64 bits, but current VFS is 32 bits...
359 	 * BEFS don't have access time. Nor inode change time. VFS
360 	 * doesn't have creation time.
361 	 */
362 
363 	inode->i_mtime =
364 	    (time_t) (fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16);
365 	inode->i_ctime = inode->i_mtime;
366 	inode->i_atime = inode->i_mtime;
367 	inode->i_blkbits = befs_sb->block_shift;
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) && !(inode->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 = &befs_file_operations;
396 		inode->i_op = &befs_file_inode_operations;
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 unaquire_bh;
407 	}
408 
409 	brelse(bh);
410 	befs_debug(sb, "<--- befs_read_inode()");
411 	return;
412 
413       unaquire_bh:
414 	brelse(bh);
415 
416       unaquire_ino_info:
417 	kmem_cache_free(befs_inode_cachep, inode->u.generic_ip);
418 
419       unaquire_none:
420 	make_bad_inode(inode);
421 	inode->u.generic_ip = NULL;
422 	befs_debug(sb, "<--- befs_read_inode() - Bad inode");
423 	return;
424 }
425 
426 /* Initialize the inode cache. Called at fs setup.
427  *
428  * Taken from NFS implementation by Al Viro.
429  */
430 static int
befs_init_inodecache(void)431 befs_init_inodecache(void)
432 {
433 	befs_inode_cachep = kmem_cache_create("befs_inode_cache",
434 					      sizeof (struct befs_inode_info),
435 					      0, SLAB_HWCACHE_ALIGN,
436 					      NULL, NULL);
437 	if (befs_inode_cachep == NULL) {
438 		printk(KERN_ERR "befs_init_inodecache: "
439 		       "Couldn't initalize inode slabcache\n");
440 		return -ENOMEM;
441 	}
442 
443 	return 0;
444 }
445 
446 /* Called at fs teardown.
447  *
448  * Taken from NFS implementation by Al Viro.
449  */
450 static void
befs_destroy_inodecache(void)451 befs_destroy_inodecache(void)
452 {
453 	if (kmem_cache_destroy(befs_inode_cachep))
454 		printk(KERN_ERR "befs_destroy_inodecache: "
455 		       "not all structures were freed\n");
456 }
457 
458 /*
459  * The inode of symbolic link is different to data stream.
460  * The data stream become link name. Unless the LONG_SYMLINK
461  * flag is set.
462  */
463 static int
befs_follow_link(struct dentry * dentry,struct nameidata * nd)464 befs_follow_link(struct dentry *dentry, struct nameidata *nd)
465 {
466 	struct super_block *sb = dentry->d_sb;
467 	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
468 	char *link;
469 	int res;
470 
471 	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
472 		befs_data_stream *data = &befs_ino->i_data.ds;
473 		befs_off_t linklen = data->size;
474 
475 		befs_debug(sb, "Follow long symlink");
476 
477 		link = kmalloc(linklen, GFP_NOFS);
478 		if (link == NULL)
479 			return -ENOMEM;
480 
481 		if (befs_read_lsymlink(sb, data, link, linklen) != linklen) {
482 			kfree(link);
483 			befs_error(sb, "Failed to read entire long symlink");
484 			return -EIO;
485 		}
486 
487 		res = vfs_follow_link(nd, link);
488 
489 		kfree(link);
490 	} else {
491 		link = befs_ino->i_data.symlink;
492 		res = vfs_follow_link(nd, link);
493 	}
494 
495 	return res;
496 }
497 
498 static int
befs_readlink(struct dentry * dentry,char * buffer,int buflen)499 befs_readlink(struct dentry *dentry, char *buffer, int buflen)
500 {
501 	struct super_block *sb = dentry->d_sb;
502 	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
503 	char *link;
504 	int res;
505 
506 	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
507 		befs_data_stream *data = &befs_ino->i_data.ds;
508 		befs_off_t linklen = data->size;
509 
510 		befs_debug(sb, "Read long symlink");
511 
512 		link = kmalloc(linklen, GFP_NOFS);
513 		if (link == NULL)
514 			return -ENOMEM;
515 
516 		if (befs_read_lsymlink(sb, data, link, linklen) != linklen) {
517 			kfree(link);
518 			befs_error(sb, "Failed to read entire long symlink");
519 			return -EIO;
520 		}
521 
522 		res = vfs_readlink(dentry, buffer, buflen, link);
523 
524 		kfree(link);
525 	} else {
526 		link = befs_ino->i_data.symlink;
527 		res = vfs_readlink(dentry, buffer, buflen, link);
528 	}
529 
530 	return res;
531 }
532 
533 /*
534  * UTF-8 to NLS charset  convert routine
535  *
536  * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
537  * the nls tables directly
538  */
539 
540 static int
befs_utf2nls(struct super_block * sb,const char * in,int in_len,char ** out,int * out_len)541 befs_utf2nls(struct super_block *sb, const char *in,
542 	     int in_len, char **out, int *out_len)
543 {
544 	struct nls_table *nls = BEFS_SB(sb)->nls;
545 	int i, o;
546 	wchar_t uni;
547 	int unilen, utflen;
548 	char *result;
549 	int maxlen = in_len;	/* The utf8->nls conversion cant make more chars */
550 
551 	befs_debug(sb, "---> utf2nls()");
552 
553 	if (!nls) {
554 		befs_error(sb, "befs_utf2nls called with no NLS table loaded");
555 		return -EINVAL;
556 	}
557 
558 	*out = result = kmalloc(maxlen, GFP_NOFS);
559 	if (!*out) {
560 		befs_error(sb, "befs_utf2nls() cannot allocate memory");
561 		*out_len = 0;
562 		return -ENOMEM;
563 	}
564 
565 	for (i = o = 0; i < in_len; i += utflen, o += unilen) {
566 
567 		/* convert from UTF-8 to Unicode */
568 		utflen = utf8_mbtowc(&uni, &in[i], in_len - i);
569 		if (utflen < 0) {
570 			goto conv_err;
571 		}
572 
573 		/* convert from Unicode to nls */
574 		unilen = nls->uni2char(uni, &result[o], 1);
575 		if (unilen < 0) {
576 			goto conv_err;
577 		}
578 	}
579 	result[o] = '\0';
580 	*out_len = o;
581 
582 	befs_debug(sb, "<--- utf2nls()");
583 
584 	return o;
585 
586       conv_err:
587 	befs_error(sb, "Name using charecter set %s contains a charecter that "
588 		   "cannot be converted to unicode.", nls->charset);
589 	befs_debug(sb, "<--- utf2nls()");
590 	kfree(result);
591 	return -EILSEQ;
592 }
593 
594 /**
595  * befs_nls2utf - Convert NLS string to utf8 encodeing
596  * @sb: Superblock
597  * @src: Input string buffer in NLS format
598  * @srclen: Length of input string in bytes
599  * @dest: The output string in UTF8 format
600  * @destlen: Length of the output buffer
601  *
602  * Converts input string @src, which is in the format of the loaded NLS map,
603  * into a utf8 string.
604  *
605  * The destination string @dest is allocated by this function and the caller is
606  * responsible for freeing it with kfree()
607  *
608  * On return, *@destlen is the length of @dest in bytes.
609  *
610  * On success, the return value is the number of utf8 charecters written to
611  * the ouput buffer @dest.
612  *
613  * On Failure, a negative number coresponding to the error code is returned.
614  */
615 
616 static int
befs_nls2utf(struct super_block * sb,const char * in,int in_len,char ** out,int * out_len)617 befs_nls2utf(struct super_block *sb, const char *in,
618 	     int in_len, char **out, int *out_len)
619 {
620 	struct nls_table *nls = BEFS_SB(sb)->nls;
621 	int i, o;
622 	wchar_t uni;
623 	int unilen, utflen;
624 	char *result;
625 	int maxlen = 3 * in_len;
626 
627 	befs_debug(sb, "---> nls2utf()\n");
628 
629 	if (!nls) {
630 		befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
631 		return -EINVAL;
632 	}
633 
634 	*out = result = kmalloc(maxlen, GFP_NOFS);
635 	if (!*out) {
636 		befs_error(sb, "befs_nls2utf() cannot allocate memory");
637 		*out_len = 0;
638 		return -ENOMEM;
639 	}
640 
641 	for (i = o = 0; i < in_len; i += unilen, o += utflen) {
642 
643 		/* convert from nls to unicode */
644 		unilen = nls->char2uni(&in[i], in_len - i, &uni);
645 		if (unilen < 0) {
646 			goto conv_err;
647 		}
648 
649 		/* convert from unicode to UTF-8 */
650 		utflen = utf8_wctomb(&result[o], uni, 3);
651 		if (utflen <= 0) {
652 			goto conv_err;
653 		}
654 	}
655 
656 	result[o] = '\0';
657 	*out_len = o;
658 
659 	befs_debug(sb, "<--- nls2utf()");
660 
661 	return i;
662 
663       conv_err:
664 	befs_error(sb, "Name using charecter set %s contains a charecter that "
665 		   "cannot be converted to unicode.", nls->charset);
666 	befs_debug(sb, "<--- nls2utf()");
667 	kfree(result);
668 	return -EILSEQ;
669 }
670 
671 /****Superblock****/
672 
673 static int
parse_options(char * options,befs_mount_options * opts)674 parse_options(char *options, befs_mount_options * opts)
675 {
676 	char *this_char;
677 	char *value;
678 	int ret = 1;
679 
680 	/* Initialize options */
681 	opts->uid = 0;
682 	opts->gid = 0;
683 	opts->use_uid = 0;
684 	opts->use_gid = 0;
685 	opts->iocharset = NULL;
686 	opts->debug = 0;
687 
688 	if (!options)
689 		return ret;
690 
691 	for (this_char = strtok(options, ","); this_char != NULL;
692 	     this_char = strtok(NULL, ",")) {
693 
694 		if ((value = strchr(this_char, '=')) != NULL)
695 			*value++ = 0;
696 
697 		if (!strcmp(this_char, "uid")) {
698 			if (!value || !*value) {
699 				ret = 0;
700 			} else {
701 				opts->uid = simple_strtoul(value, &value, 0);
702 				opts->use_uid = 1;
703 				if (*value) {
704 					printk(KERN_ERR "BEFS: Invalid uid "
705 					       "option: %s\n", value);
706 					ret = 0;
707 				}
708 			}
709 		} else if (!strcmp(this_char, "gid")) {
710 			if (!value || !*value)
711 				ret = 0;
712 			else {
713 				opts->gid = simple_strtoul(value, &value, 0);
714 				opts->use_gid = 1;
715 				if (*value) {
716 					printk(KERN_ERR
717 					       "BEFS: Invalid gid option: "
718 					       "%s\n", value);
719 					ret = 0;
720 				}
721 			}
722 		} else if (!strcmp(this_char, "iocharset") && value) {
723 			char *p = value;
724 			int len;
725 
726 			while (*value && *value != ',')
727 				value++;
728 			len = value - p;
729 			if (len) {
730 				char *buffer = kmalloc(len + 1, GFP_NOFS);
731 				if (buffer) {
732 					opts->iocharset = buffer;
733 					memcpy(buffer, p, len);
734 					buffer[len] = 0;
735 
736 				} else {
737 					printk(KERN_ERR "BEFS: "
738 					       "cannot allocate memory\n");
739 					ret = 0;
740 				}
741 			}
742 		} else if (!strcmp(this_char, "debug")) {
743 			opts->debug = 1;
744 		}
745 	}
746 
747 	return ret;
748 }
749 
750 /* This function has the responsibiltiy of getting the
751  * filesystem ready for unmounting.
752  * Basicly, we free everything that we allocated in
753  * befs_read_inode
754  */
755 static void
befs_put_super(struct super_block * sb)756 befs_put_super(struct super_block *sb)
757 {
758 	if (BEFS_SB(sb)->mount_opts.iocharset) {
759 		kfree(BEFS_SB(sb)->mount_opts.iocharset);
760 		BEFS_SB(sb)->mount_opts.iocharset = NULL;
761 	}
762 
763 	if (BEFS_SB(sb)->nls) {
764 		unload_nls(BEFS_SB(sb)->nls);
765 		BEFS_SB(sb)->nls = NULL;
766 	}
767 
768 	if (sb->u.generic_sbp) {
769 		kfree(sb->u.generic_sbp);
770 		sb->u.generic_sbp = NULL;
771 	}
772 	return;
773 }
774 
775 /* Allocate private field of the superblock, fill it.
776  *
777  * Finish filling the public superblock fields
778  * Make the root directory
779  * Load a set of NLS translations if needed.
780  */
781 static struct super_block *
befs_read_super(struct super_block * sb,void * data,int silent)782 befs_read_super(struct super_block *sb, void *data, int silent)
783 {
784 	struct buffer_head *bh;
785 	befs_sb_info *befs_sb;
786 	befs_super_block *disk_sb;
787 	int blocksize;
788 
789 	const unsigned long sb_block = 0;
790 	const off_t x86_sb_off = 512;
791 
792 	sb->u.generic_sbp = kmalloc(sizeof (struct befs_sb_info), GFP_NOFS);
793 	if (sb->u.generic_sbp == NULL) {
794 		printk(KERN_ERR
795 		       "BeFS(%s): Unable to allocate memory for private "
796 		       "portion of superblock. Bailing.\n",
797 		       kdevname(sb->s_dev));
798 		goto unaquire_none;
799 	}
800 	befs_sb = BEFS_SB(sb);
801 
802 	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
803 		befs_error(sb, "cannot parse mount options");
804 		goto unaquire_priv_sbp;
805 	}
806 
807 	befs_debug(sb, "---> befs_read_super()");
808 
809 #ifndef CONFIG_BEFS_RW
810 	if (!(sb->s_flags & MS_RDONLY)) {
811 		befs_warning(sb,
812 			     "No write support. Marking filesystem read-only");
813 		sb->s_flags |= MS_RDONLY;
814 	}
815 #endif				/* CONFIG_BEFS_RW */
816 
817 	/*
818 	 * Set dummy blocksize to read super block.
819 	 * Will be set to real fs blocksize later.
820 	 *
821 	 * Linux 2.4.10 and later refuse to read blocks smaller than
822 	 * the hardsect size for the device. But we also need to read at
823 	 * least 1k to get the second 512 bytes of the volume.
824 	 * -WD 10-26-01
825 	 */
826 	blocksize = max_t(int, get_hardsect_size(sb->s_dev), 1024);
827 	set_blocksize(sb->s_dev, blocksize);
828 
829 	if (!(bh = bread(sb->s_dev, sb_block, blocksize))) {
830 		befs_error(sb, "unable to read superblock");
831 		goto unaquire_priv_sbp;
832 	}
833 
834 	/* account for offset of super block on x86 */
835 	disk_sb = (befs_super_block *) bh->b_data;
836 	if ((le32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1) ||
837 	    (be32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1)) {
838 		befs_debug(sb, "Using PPC superblock location");
839 	} else {
840 		befs_debug(sb, "Using x86 superblock location");
841 		disk_sb =
842 		    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
843 	}
844 
845 	if (befs_load_sb(sb, disk_sb) != BEFS_OK)
846 		goto unaquire_bh;
847 
848 	befs_dump_super_block(sb, disk_sb);
849 
850 	brelse(bh);
851 
852 	if (befs_check_sb(sb) != BEFS_OK)
853 		goto unaquire_priv_sbp;
854 
855 	/*
856 	 * set up enough so that it can read an inode
857 	 * Fill in kernel superblock fields from private sb
858 	 */
859 	sb->s_magic = BEFS_SUPER_MAGIC;
860 	sb->s_blocksize = (ulong) befs_sb->block_size;
861 	sb->s_blocksize_bits = (unsigned char) befs_sb->block_shift;
862 	sb->s_op = (struct super_operations *) &befs_sops;
863 	sb->s_root =
864 	    d_alloc_root(iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir))));
865 	if (!sb->s_root) {
866 		befs_error(sb, "get root inode failed");
867 		goto unaquire_priv_sbp;
868 	}
869 
870 	/* load nls library */
871 	if (befs_sb->mount_opts.iocharset) {
872 		befs_debug(sb, "Loading nls: %s",
873 			   befs_sb->mount_opts.iocharset);
874 		befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
875 		if (!befs_sb->nls) {
876 			befs_warning(sb, "Cannot load nls %s"
877 				     "loding default nls",
878 				     befs_sb->mount_opts.iocharset);
879 			befs_sb->nls = load_nls_default();
880 		}
881 	}
882 
883 	/* Set real blocksize of fs */
884 	set_blocksize(sb->s_dev, (int) befs_sb->block_size);
885 
886 	return sb;
887 /*****************/
888       unaquire_bh:
889 	brelse(bh);
890 
891       unaquire_priv_sbp:
892 	kfree(sb->u.generic_sbp);
893 
894       unaquire_none:
895 	sb->s_dev = 0;
896 	sb->u.generic_sbp = NULL;
897 	return NULL;
898 }
899 
900 static int
befs_remount(struct super_block * sb,int * flags,char * data)901 befs_remount(struct super_block *sb, int *flags, char *data)
902 {
903 	if (!(*flags & MS_RDONLY))
904 		return -EINVAL;
905 	return 0;
906 }
907 
908 static int
befs_statfs(struct super_block * sb,struct statfs * buf)909 befs_statfs(struct super_block *sb, struct statfs *buf)
910 {
911 
912 	befs_debug(sb, "---> befs_statfs()");
913 
914 	buf->f_type = BEFS_SUPER_MAGIC;
915 	buf->f_bsize = sb->s_blocksize;
916 	buf->f_blocks = BEFS_SB(sb)->num_blocks;
917 	buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
918 	buf->f_bavail = buf->f_bfree;
919 	buf->f_files = 0;	/* UNKNOWN */
920 	buf->f_ffree = 0;	/* UNKNOWN */
921 	buf->f_namelen = BEFS_NAME_LEN;
922 
923 	befs_debug(sb, "<--- befs_statfs()");
924 
925 	return 0;
926 }
927 
928 /*
929 	Makes a variable of type file_system_type,
930 	named befs_fs_tipe, identified by the "befs" string,
931 	and containing a reference to the befs_read_super function
932 
933 	Macro declared in <linux/fs.h>
934 */
935 static DECLARE_FSTYPE_DEV(befs_fs_type, "befs", befs_read_super);
936 
937 static int __init
init_befs_fs(void)938 init_befs_fs(void)
939 {
940 	int err;
941 
942 	printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
943 
944 	err = befs_init_inodecache();
945 	if (err)
946 		return err;
947 
948 	return register_filesystem(&befs_fs_type);
949 }
950 
951 static void __exit
exit_befs_fs(void)952 exit_befs_fs(void)
953 {
954 	befs_destroy_inodecache();
955 
956 	unregister_filesystem(&befs_fs_type);
957 }
958 
959 /*
960 Macros that typecheck the init and exit functions,
961 ensures that they are called at init and cleanup,
962 and eliminates warnings about unused functions.
963 */
964 module_init(init_befs_fs)
965     module_exit(exit_befs_fs)
966