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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 dentry *, 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 dentry *dentry, struct kstatfs *buf)
884 {
885 struct super_block *sb = dentry->d_sb;
886
887 befs_debug(sb, "---> befs_statfs()");
888
889 buf->f_type = BEFS_SUPER_MAGIC;
890 buf->f_bsize = sb->s_blocksize;
891 buf->f_blocks = BEFS_SB(sb)->num_blocks;
892 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
893 buf->f_bavail = buf->f_bfree;
894 buf->f_files = 0; /* UNKNOWN */
895 buf->f_ffree = 0; /* UNKNOWN */
896 buf->f_namelen = BEFS_NAME_LEN;
897
898 befs_debug(sb, "<--- befs_statfs()");
899
900 return 0;
901 }
902
903 static int
904 befs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name,
905 void *data, struct vfsmount *mnt)
906 {
907 return get_sb_bdev(fs_type, flags, dev_name, data, befs_fill_super,
908 mnt);
909 }
910
911 static struct file_system_type befs_fs_type = {
912 .owner = THIS_MODULE,
913 .name = "befs",
914 .get_sb = befs_get_sb,
915 .kill_sb = kill_block_super,
916 .fs_flags = FS_REQUIRES_DEV,
917 };
918
919 static int __init
920 init_befs_fs(void)
921 {
922 int err;
923
924 printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
925
926 err = befs_init_inodecache();
927 if (err)
928 goto unaquire_none;
929
930 err = register_filesystem(&befs_fs_type);
931 if (err)
932 goto unaquire_inodecache;
933
934 return 0;
935
936 unaquire_inodecache:
937 befs_destroy_inodecache();
938
939 unaquire_none:
940 return err;
941 }
942
943 static void __exit
944 exit_befs_fs(void)
945 {
946 befs_destroy_inodecache();
947
948 unregister_filesystem(&befs_fs_type);
949 }
950
951 /*
952 Macros that typecheck the init and exit functions,
953 ensures that they are called at init and cleanup,
954 and eliminates warnings about unused functions.
955 */
956 module_init(init_befs_fs)
957 module_exit(exit_befs_fs)