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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/fs.h>
13#include <linux/errno.h>
14#include <linux/stat.h>
15#include <linux/nls.h>
16#include <linux/buffer_head.h>
17#include <linux/vfs.h>
18#include <linux/parser.h>
19#include <linux/namei.h>
20#include <linux/sched.h>
21
22#include "befs.h"
23#include "btree.h"
24#include "inode.h"
25#include "datastream.h"
26#include "super.h"
27#include "io.h"
28
29MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
30MODULE_AUTHOR("Will Dyson");
31MODULE_LICENSE("GPL");
32
33/* The units the vfs expects inode->i_blocks to be in */
34#define VFS_BLOCK_SIZE 512
35
36static int befs_readdir(struct file *, struct dir_context *);
37static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
38static int befs_readpage(struct file *file, struct page *page);
39static sector_t befs_bmap(struct address_space *mapping, sector_t block);
40static struct dentry *befs_lookup(struct inode *, struct dentry *, unsigned int);
41static struct inode *befs_iget(struct super_block *, unsigned long);
42static struct inode *befs_alloc_inode(struct super_block *sb);
43static void befs_destroy_inode(struct inode *inode);
44static void befs_destroy_inodecache(void);
45static int befs_symlink_readpage(struct file *, struct page *);
46static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
47 char **out, int *out_len);
48static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
49 char **out, int *out_len);
50static void befs_put_super(struct super_block *);
51static int befs_remount(struct super_block *, int *, char *);
52static int befs_statfs(struct dentry *, struct kstatfs *);
53static int parse_options(char *, struct befs_mount_options *);
54
55static const struct super_operations befs_sops = {
56 .alloc_inode = befs_alloc_inode, /* allocate a new inode */
57 .destroy_inode = befs_destroy_inode, /* deallocate an inode */
58 .put_super = befs_put_super, /* uninit super */
59 .statfs = befs_statfs, /* statfs */
60 .remount_fs = befs_remount,
61 .show_options = generic_show_options,
62};
63
64/* slab cache for befs_inode_info objects */
65static struct kmem_cache *befs_inode_cachep;
66
67static const struct file_operations befs_dir_operations = {
68 .read = generic_read_dir,
69 .iterate = befs_readdir,
70 .llseek = generic_file_llseek,
71};
72
73static const struct inode_operations befs_dir_inode_operations = {
74 .lookup = befs_lookup,
75};
76
77static const struct address_space_operations befs_aops = {
78 .readpage = befs_readpage,
79 .bmap = befs_bmap,
80};
81
82static const struct address_space_operations befs_symlink_aops = {
83 .readpage = befs_symlink_readpage,
84};
85
86/*
87 * Called by generic_file_read() to read a page of data
88 *
89 * In turn, simply calls a generic block read function and
90 * passes it the address of befs_get_block, for mapping file
91 * positions to disk blocks.
92 */
93static int
94befs_readpage(struct file *file, struct page *page)
95{
96 return block_read_full_page(page, befs_get_block);
97}
98
99static sector_t
100befs_bmap(struct address_space *mapping, sector_t block)
101{
102 return generic_block_bmap(mapping, block, befs_get_block);
103}
104
105/*
106 * Generic function to map a file position (block) to a
107 * disk offset (passed back in bh_result).
108 *
109 * Used by many higher level functions.
110 *
111 * Calls befs_fblock2brun() in datastream.c to do the real work.
112 *
113 * -WD 10-26-01
114 */
115
116static int
117befs_get_block(struct inode *inode, sector_t block,
118 struct buffer_head *bh_result, int create)
119{
120 struct super_block *sb = inode->i_sb;
121 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
122 befs_block_run run = BAD_IADDR;
123 int res = 0;
124 ulong disk_off;
125
126 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
127 (unsigned long)inode->i_ino, (long)block);
128 if (create) {
129 befs_error(sb, "befs_get_block() was asked to write to "
130 "block %ld in inode %lu", (long)block,
131 (unsigned long)inode->i_ino);
132 return -EPERM;
133 }
134
135 res = befs_fblock2brun(sb, ds, block, &run);
136 if (res != BEFS_OK) {
137 befs_error(sb,
138 "<--- %s for inode %lu, block %ld ERROR",
139 __func__, (unsigned long)inode->i_ino,
140 (long)block);
141 return -EFBIG;
142 }
143
144 disk_off = (ulong) iaddr2blockno(sb, &run);
145
146 map_bh(bh_result, inode->i_sb, disk_off);
147
148 befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu",
149 __func__, (unsigned long)inode->i_ino, (long)block,
150 (unsigned long)disk_off);
151
152 return 0;
153}
154
155static struct dentry *
156befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
157{
158 struct inode *inode = NULL;
159 struct super_block *sb = dir->i_sb;
160 befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
161 befs_off_t offset;
162 int ret;
163 int utfnamelen;
164 char *utfname;
165 const char *name = dentry->d_name.name;
166
167 befs_debug(sb, "---> %s name %pd inode %ld", __func__,
168 dentry, dir->i_ino);
169
170 /* Convert to UTF-8 */
171 if (BEFS_SB(sb)->nls) {
172 ret =
173 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
174 if (ret < 0) {
175 befs_debug(sb, "<--- %s ERROR", __func__);
176 return ERR_PTR(ret);
177 }
178 ret = befs_btree_find(sb, ds, utfname, &offset);
179 kfree(utfname);
180
181 } else {
182 ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
183 }
184
185 if (ret == BEFS_BT_NOT_FOUND) {
186 befs_debug(sb, "<--- %s %pd not found", __func__, dentry);
187 return ERR_PTR(-ENOENT);
188
189 } else if (ret != BEFS_OK || offset == 0) {
190 befs_warning(sb, "<--- %s Error", __func__);
191 return ERR_PTR(-ENODATA);
192 }
193
194 inode = befs_iget(dir->i_sb, (ino_t) offset);
195 if (IS_ERR(inode))
196 return ERR_CAST(inode);
197
198 d_add(dentry, inode);
199
200 befs_debug(sb, "<--- %s", __func__);
201
202 return NULL;
203}
204
205static int
206befs_readdir(struct file *file, struct dir_context *ctx)
207{
208 struct inode *inode = file_inode(file);
209 struct super_block *sb = inode->i_sb;
210 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
211 befs_off_t value;
212 int result;
213 size_t keysize;
214 unsigned char d_type;
215 char keybuf[BEFS_NAME_LEN + 1];
216
217 befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld",
218 __func__, file, inode->i_ino, ctx->pos);
219
220more:
221 result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,
222 keybuf, &keysize, &value);
223
224 if (result == BEFS_ERR) {
225 befs_debug(sb, "<--- %s ERROR", __func__);
226 befs_error(sb, "IO error reading %pD (inode %lu)",
227 file, inode->i_ino);
228 return -EIO;
229
230 } else if (result == BEFS_BT_END) {
231 befs_debug(sb, "<--- %s END", __func__);
232 return 0;
233
234 } else if (result == BEFS_BT_EMPTY) {
235 befs_debug(sb, "<--- %s Empty directory", __func__);
236 return 0;
237 }
238
239 d_type = DT_UNKNOWN;
240
241 /* Convert to NLS */
242 if (BEFS_SB(sb)->nls) {
243 char *nlsname;
244 int nlsnamelen;
245 result =
246 befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
247 if (result < 0) {
248 befs_debug(sb, "<--- %s ERROR", __func__);
249 return result;
250 }
251 if (!dir_emit(ctx, nlsname, nlsnamelen,
252 (ino_t) value, d_type)) {
253 kfree(nlsname);
254 return 0;
255 }
256 kfree(nlsname);
257 } else {
258 if (!dir_emit(ctx, keybuf, keysize,
259 (ino_t) value, d_type))
260 return 0;
261 }
262 ctx->pos++;
263 goto more;
264}
265
266static struct inode *
267befs_alloc_inode(struct super_block *sb)
268{
269 struct befs_inode_info *bi;
270
271 bi = kmem_cache_alloc(befs_inode_cachep, GFP_KERNEL);
272 if (!bi)
273 return NULL;
274 return &bi->vfs_inode;
275}
276
277static void befs_i_callback(struct rcu_head *head)
278{
279 struct inode *inode = container_of(head, struct inode, i_rcu);
280 kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
281}
282
283static void befs_destroy_inode(struct inode *inode)
284{
285 call_rcu(&inode->i_rcu, befs_i_callback);
286}
287
288static void init_once(void *foo)
289{
290 struct befs_inode_info *bi = (struct befs_inode_info *) foo;
291
292 inode_init_once(&bi->vfs_inode);
293}
294
295static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
296{
297 struct buffer_head *bh = NULL;
298 befs_inode *raw_inode = NULL;
299 struct befs_sb_info *befs_sb = BEFS_SB(sb);
300 struct befs_inode_info *befs_ino = NULL;
301 struct inode *inode;
302 long ret = -EIO;
303
304 befs_debug(sb, "---> %s inode = %lu", __func__, ino);
305
306 inode = iget_locked(sb, ino);
307 if (!inode)
308 return ERR_PTR(-ENOMEM);
309 if (!(inode->i_state & I_NEW))
310 return inode;
311
312 befs_ino = BEFS_I(inode);
313
314 /* convert from vfs's inode number to befs's inode number */
315 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
316
317 befs_debug(sb, " real inode number [%u, %hu, %hu]",
318 befs_ino->i_inode_num.allocation_group,
319 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
320
321 bh = befs_bread(sb, inode->i_ino);
322 if (!bh) {
323 befs_error(sb, "unable to read inode block - "
324 "inode = %lu", inode->i_ino);
325 goto unacquire_none;
326 }
327
328 raw_inode = (befs_inode *) bh->b_data;
329
330 befs_dump_inode(sb, raw_inode);
331
332 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
333 befs_error(sb, "Bad inode: %lu", inode->i_ino);
334 goto unacquire_bh;
335 }
336
337 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
338
339 /*
340 * set uid and gid. But since current BeOS is single user OS, so
341 * you can change by "uid" or "gid" options.
342 */
343
344 inode->i_uid = befs_sb->mount_opts.use_uid ?
345 befs_sb->mount_opts.uid :
346 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
347 inode->i_gid = befs_sb->mount_opts.use_gid ?
348 befs_sb->mount_opts.gid :
349 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
350
351 set_nlink(inode, 1);
352
353 /*
354 * BEFS's time is 64 bits, but current VFS is 32 bits...
355 * BEFS don't have access time. Nor inode change time. VFS
356 * doesn't have creation time.
357 * Also, the lower 16 bits of the last_modified_time and
358 * create_time are just a counter to help ensure uniqueness
359 * for indexing purposes. (PFD, page 54)
360 */
361
362 inode->i_mtime.tv_sec =
363 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
364 inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */
365 inode->i_ctime = inode->i_mtime;
366 inode->i_atime = inode->i_mtime;
367
368 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
369 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
370 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
371 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
372
373 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
374 inode->i_size = 0;
375 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
376 strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
377 BEFS_SYMLINK_LEN);
378 } else {
379 int num_blks;
380
381 befs_ino->i_data.ds =
382 fsds_to_cpu(sb, &raw_inode->data.datastream);
383
384 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
385 inode->i_blocks =
386 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
387 inode->i_size = befs_ino->i_data.ds.size;
388 }
389
390 inode->i_mapping->a_ops = &befs_aops;
391
392 if (S_ISREG(inode->i_mode)) {
393 inode->i_fop = &generic_ro_fops;
394 } else if (S_ISDIR(inode->i_mode)) {
395 inode->i_op = &befs_dir_inode_operations;
396 inode->i_fop = &befs_dir_operations;
397 } else if (S_ISLNK(inode->i_mode)) {
398 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
399 inode->i_op = &page_symlink_inode_operations;
400 inode_nohighmem(inode);
401 inode->i_mapping->a_ops = &befs_symlink_aops;
402 } else {
403 inode->i_link = befs_ino->i_data.symlink;
404 inode->i_op = &simple_symlink_inode_operations;
405 }
406 } else {
407 befs_error(sb, "Inode %lu is not a regular file, "
408 "directory or symlink. THAT IS WRONG! BeFS has no "
409 "on disk special files", inode->i_ino);
410 goto unacquire_bh;
411 }
412
413 brelse(bh);
414 befs_debug(sb, "<--- %s", __func__);
415 unlock_new_inode(inode);
416 return inode;
417
418 unacquire_bh:
419 brelse(bh);
420
421 unacquire_none:
422 iget_failed(inode);
423 befs_debug(sb, "<--- %s - Bad inode", __func__);
424 return ERR_PTR(ret);
425}
426
427/* Initialize the inode cache. Called at fs setup.
428 *
429 * Taken from NFS implementation by Al Viro.
430 */
431static int __init
432befs_init_inodecache(void)
433{
434 befs_inode_cachep = kmem_cache_create("befs_inode_cache",
435 sizeof (struct befs_inode_info),
436 0, (SLAB_RECLAIM_ACCOUNT|
437 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
438 init_once);
439 if (befs_inode_cachep == NULL) {
440 pr_err("%s: Couldn't initialize inode slabcache\n", __func__);
441 return -ENOMEM;
442 }
443 return 0;
444}
445
446/* Called at fs teardown.
447 *
448 * Taken from NFS implementation by Al Viro.
449 */
450static void
451befs_destroy_inodecache(void)
452{
453 /*
454 * Make sure all delayed rcu free inodes are flushed before we
455 * destroy cache.
456 */
457 rcu_barrier();
458 kmem_cache_destroy(befs_inode_cachep);
459}
460
461/*
462 * The inode of symbolic link is different to data stream.
463 * The data stream become link name. Unless the LONG_SYMLINK
464 * flag is set.
465 */
466static int befs_symlink_readpage(struct file *unused, struct page *page)
467{
468 struct inode *inode = page->mapping->host;
469 struct super_block *sb = inode->i_sb;
470 struct befs_inode_info *befs_ino = BEFS_I(inode);
471 befs_data_stream *data = &befs_ino->i_data.ds;
472 befs_off_t len = data->size;
473 char *link = page_address(page);
474
475 if (len == 0 || len > PAGE_SIZE) {
476 befs_error(sb, "Long symlink with illegal length");
477 goto fail;
478 }
479 befs_debug(sb, "Follow long symlink");
480
481 if (befs_read_lsymlink(sb, data, link, len) != len) {
482 befs_error(sb, "Failed to read entire long symlink");
483 goto fail;
484 }
485 link[len - 1] = '\0';
486 SetPageUptodate(page);
487 unlock_page(page);
488 return 0;
489fail:
490 SetPageError(page);
491 unlock_page(page);
492 return -EIO;
493}
494
495/*
496 * UTF-8 to NLS charset convert routine
497 *
498 *
499 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
500 * the nls tables directly
501 */
502
503static int
504befs_utf2nls(struct super_block *sb, const char *in,
505 int in_len, char **out, int *out_len)
506{
507 struct nls_table *nls = BEFS_SB(sb)->nls;
508 int i, o;
509 unicode_t uni;
510 int unilen, utflen;
511 char *result;
512 /* The utf8->nls conversion won't make the final nls string bigger
513 * than the utf one, but if the string is pure ascii they'll have the
514 * same width and an extra char is needed to save the additional \0
515 */
516 int maxlen = in_len + 1;
517
518 befs_debug(sb, "---> %s", __func__);
519
520 if (!nls) {
521 befs_error(sb, "%s called with no NLS table loaded", __func__);
522 return -EINVAL;
523 }
524
525 *out = result = kmalloc(maxlen, GFP_NOFS);
526 if (!*out) {
527 befs_error(sb, "%s cannot allocate memory", __func__);
528 *out_len = 0;
529 return -ENOMEM;
530 }
531
532 for (i = o = 0; i < in_len; i += utflen, o += unilen) {
533
534 /* convert from UTF-8 to Unicode */
535 utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
536 if (utflen < 0)
537 goto conv_err;
538
539 /* convert from Unicode to nls */
540 if (uni > MAX_WCHAR_T)
541 goto conv_err;
542 unilen = nls->uni2char(uni, &result[o], in_len - o);
543 if (unilen < 0)
544 goto conv_err;
545 }
546 result[o] = '\0';
547 *out_len = o;
548
549 befs_debug(sb, "<--- %s", __func__);
550
551 return o;
552
553 conv_err:
554 befs_error(sb, "Name using character set %s contains a character that "
555 "cannot be converted to unicode.", nls->charset);
556 befs_debug(sb, "<--- %s", __func__);
557 kfree(result);
558 return -EILSEQ;
559}
560
561/**
562 * befs_nls2utf - Convert NLS string to utf8 encodeing
563 * @sb: Superblock
564 * @in: Input string buffer in NLS format
565 * @in_len: Length of input string in bytes
566 * @out: The output string in UTF-8 format
567 * @out_len: Length of the output buffer
568 *
569 * Converts input string @in, which is in the format of the loaded NLS map,
570 * into a utf8 string.
571 *
572 * The destination string @out is allocated by this function and the caller is
573 * responsible for freeing it with kfree()
574 *
575 * On return, *@out_len is the length of @out in bytes.
576 *
577 * On success, the return value is the number of utf8 characters written to
578 * the output buffer @out.
579 *
580 * On Failure, a negative number coresponding to the error code is returned.
581 */
582
583static int
584befs_nls2utf(struct super_block *sb, const char *in,
585 int in_len, char **out, int *out_len)
586{
587 struct nls_table *nls = BEFS_SB(sb)->nls;
588 int i, o;
589 wchar_t uni;
590 int unilen, utflen;
591 char *result;
592 /* There're nls characters that will translate to 3-chars-wide UTF-8
593 * characters, a additional byte is needed to save the final \0
594 * in special cases */
595 int maxlen = (3 * in_len) + 1;
596
597 befs_debug(sb, "---> %s\n", __func__);
598
599 if (!nls) {
600 befs_error(sb, "%s called with no NLS table loaded.",
601 __func__);
602 return -EINVAL;
603 }
604
605 *out = result = kmalloc(maxlen, GFP_NOFS);
606 if (!*out) {
607 befs_error(sb, "%s cannot allocate memory", __func__);
608 *out_len = 0;
609 return -ENOMEM;
610 }
611
612 for (i = o = 0; i < in_len; i += unilen, o += utflen) {
613
614 /* convert from nls to unicode */
615 unilen = nls->char2uni(&in[i], in_len - i, &uni);
616 if (unilen < 0)
617 goto conv_err;
618
619 /* convert from unicode to UTF-8 */
620 utflen = utf32_to_utf8(uni, &result[o], 3);
621 if (utflen <= 0)
622 goto conv_err;
623 }
624
625 result[o] = '\0';
626 *out_len = o;
627
628 befs_debug(sb, "<--- %s", __func__);
629
630 return i;
631
632 conv_err:
633 befs_error(sb, "Name using charecter set %s contains a charecter that "
634 "cannot be converted to unicode.", nls->charset);
635 befs_debug(sb, "<--- %s", __func__);
636 kfree(result);
637 return -EILSEQ;
638}
639
640/**
641 * Use the
642 *
643 */
644enum {
645 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
646};
647
648static const match_table_t befs_tokens = {
649 {Opt_uid, "uid=%d"},
650 {Opt_gid, "gid=%d"},
651 {Opt_charset, "iocharset=%s"},
652 {Opt_debug, "debug"},
653 {Opt_err, NULL}
654};
655
656static int
657parse_options(char *options, struct befs_mount_options *opts)
658{
659 char *p;
660 substring_t args[MAX_OPT_ARGS];
661 int option;
662 kuid_t uid;
663 kgid_t gid;
664
665 /* Initialize options */
666 opts->uid = GLOBAL_ROOT_UID;
667 opts->gid = GLOBAL_ROOT_GID;
668 opts->use_uid = 0;
669 opts->use_gid = 0;
670 opts->iocharset = NULL;
671 opts->debug = 0;
672
673 if (!options)
674 return 1;
675
676 while ((p = strsep(&options, ",")) != NULL) {
677 int token;
678 if (!*p)
679 continue;
680
681 token = match_token(p, befs_tokens, args);
682 switch (token) {
683 case Opt_uid:
684 if (match_int(&args[0], &option))
685 return 0;
686 uid = INVALID_UID;
687 if (option >= 0)
688 uid = make_kuid(current_user_ns(), option);
689 if (!uid_valid(uid)) {
690 pr_err("Invalid uid %d, "
691 "using default\n", option);
692 break;
693 }
694 opts->uid = uid;
695 opts->use_uid = 1;
696 break;
697 case Opt_gid:
698 if (match_int(&args[0], &option))
699 return 0;
700 gid = INVALID_GID;
701 if (option >= 0)
702 gid = make_kgid(current_user_ns(), option);
703 if (!gid_valid(gid)) {
704 pr_err("Invalid gid %d, "
705 "using default\n", option);
706 break;
707 }
708 opts->gid = gid;
709 opts->use_gid = 1;
710 break;
711 case Opt_charset:
712 kfree(opts->iocharset);
713 opts->iocharset = match_strdup(&args[0]);
714 if (!opts->iocharset) {
715 pr_err("allocation failure for "
716 "iocharset string\n");
717 return 0;
718 }
719 break;
720 case Opt_debug:
721 opts->debug = 1;
722 break;
723 default:
724 pr_err("Unrecognized mount option \"%s\" "
725 "or missing value\n", p);
726 return 0;
727 }
728 }
729 return 1;
730}
731
732/* This function has the responsibiltiy of getting the
733 * filesystem ready for unmounting.
734 * Basically, we free everything that we allocated in
735 * befs_read_inode
736 */
737static void
738befs_put_super(struct super_block *sb)
739{
740 kfree(BEFS_SB(sb)->mount_opts.iocharset);
741 BEFS_SB(sb)->mount_opts.iocharset = NULL;
742 unload_nls(BEFS_SB(sb)->nls);
743 kfree(sb->s_fs_info);
744 sb->s_fs_info = NULL;
745}
746
747/* Allocate private field of the superblock, fill it.
748 *
749 * Finish filling the public superblock fields
750 * Make the root directory
751 * Load a set of NLS translations if needed.
752 */
753static int
754befs_fill_super(struct super_block *sb, void *data, int silent)
755{
756 struct buffer_head *bh;
757 struct befs_sb_info *befs_sb;
758 befs_super_block *disk_sb;
759 struct inode *root;
760 long ret = -EINVAL;
761 const unsigned long sb_block = 0;
762 const off_t x86_sb_off = 512;
763
764 save_mount_options(sb, data);
765
766 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);
767 if (sb->s_fs_info == NULL) {
768 pr_err("(%s): Unable to allocate memory for private "
769 "portion of superblock. Bailing.\n", sb->s_id);
770 goto unacquire_none;
771 }
772 befs_sb = BEFS_SB(sb);
773
774 if (!parse_options((char *) data, &befs_sb->mount_opts)) {
775 befs_error(sb, "cannot parse mount options");
776 goto unacquire_priv_sbp;
777 }
778
779 befs_debug(sb, "---> %s", __func__);
780
781 if (!(sb->s_flags & MS_RDONLY)) {
782 befs_warning(sb,
783 "No write support. Marking filesystem read-only");
784 sb->s_flags |= MS_RDONLY;
785 }
786
787 /*
788 * Set dummy blocksize to read super block.
789 * Will be set to real fs blocksize later.
790 *
791 * Linux 2.4.10 and later refuse to read blocks smaller than
792 * the hardsect size for the device. But we also need to read at
793 * least 1k to get the second 512 bytes of the volume.
794 * -WD 10-26-01
795 */
796 sb_min_blocksize(sb, 1024);
797
798 if (!(bh = sb_bread(sb, sb_block))) {
799 befs_error(sb, "unable to read superblock");
800 goto unacquire_priv_sbp;
801 }
802
803 /* account for offset of super block on x86 */
804 disk_sb = (befs_super_block *) bh->b_data;
805 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
806 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
807 befs_debug(sb, "Using PPC superblock location");
808 } else {
809 befs_debug(sb, "Using x86 superblock location");
810 disk_sb =
811 (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
812 }
813
814 if ((befs_load_sb(sb, disk_sb) != BEFS_OK) ||
815 (befs_check_sb(sb) != BEFS_OK))
816 goto unacquire_bh;
817
818 befs_dump_super_block(sb, disk_sb);
819
820 brelse(bh);
821
822 if( befs_sb->num_blocks > ~((sector_t)0) ) {
823 befs_error(sb, "blocks count: %llu "
824 "is larger than the host can use",
825 befs_sb->num_blocks);
826 goto unacquire_priv_sbp;
827 }
828
829 /*
830 * set up enough so that it can read an inode
831 * Fill in kernel superblock fields from private sb
832 */
833 sb->s_magic = BEFS_SUPER_MAGIC;
834 /* Set real blocksize of fs */
835 sb_set_blocksize(sb, (ulong) befs_sb->block_size);
836 sb->s_op = &befs_sops;
837 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
838 if (IS_ERR(root)) {
839 ret = PTR_ERR(root);
840 goto unacquire_priv_sbp;
841 }
842 sb->s_root = d_make_root(root);
843 if (!sb->s_root) {
844 befs_error(sb, "get root inode failed");
845 goto unacquire_priv_sbp;
846 }
847
848 /* load nls library */
849 if (befs_sb->mount_opts.iocharset) {
850 befs_debug(sb, "Loading nls: %s",
851 befs_sb->mount_opts.iocharset);
852 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
853 if (!befs_sb->nls) {
854 befs_warning(sb, "Cannot load nls %s"
855 " loading default nls",
856 befs_sb->mount_opts.iocharset);
857 befs_sb->nls = load_nls_default();
858 }
859 /* load default nls if none is specified in mount options */
860 } else {
861 befs_debug(sb, "Loading default nls");
862 befs_sb->nls = load_nls_default();
863 }
864
865 return 0;
866/*****************/
867 unacquire_bh:
868 brelse(bh);
869
870 unacquire_priv_sbp:
871 kfree(befs_sb->mount_opts.iocharset);
872 kfree(sb->s_fs_info);
873
874 unacquire_none:
875 sb->s_fs_info = NULL;
876 return ret;
877}
878
879static int
880befs_remount(struct super_block *sb, int *flags, char *data)
881{
882 sync_filesystem(sb);
883 if (!(*flags & MS_RDONLY))
884 return -EINVAL;
885 return 0;
886}
887
888static int
889befs_statfs(struct dentry *dentry, struct kstatfs *buf)
890{
891 struct super_block *sb = dentry->d_sb;
892 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
893
894 befs_debug(sb, "---> %s", __func__);
895
896 buf->f_type = BEFS_SUPER_MAGIC;
897 buf->f_bsize = sb->s_blocksize;
898 buf->f_blocks = BEFS_SB(sb)->num_blocks;
899 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
900 buf->f_bavail = buf->f_bfree;
901 buf->f_files = 0; /* UNKNOWN */
902 buf->f_ffree = 0; /* UNKNOWN */
903 buf->f_fsid.val[0] = (u32)id;
904 buf->f_fsid.val[1] = (u32)(id >> 32);
905 buf->f_namelen = BEFS_NAME_LEN;
906
907 befs_debug(sb, "<--- %s", __func__);
908
909 return 0;
910}
911
912static struct dentry *
913befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
914 void *data)
915{
916 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
917}
918
919static struct file_system_type befs_fs_type = {
920 .owner = THIS_MODULE,
921 .name = "befs",
922 .mount = befs_mount,
923 .kill_sb = kill_block_super,
924 .fs_flags = FS_REQUIRES_DEV,
925};
926MODULE_ALIAS_FS("befs");
927
928static int __init
929init_befs_fs(void)
930{
931 int err;
932
933 pr_info("version: %s\n", BEFS_VERSION);
934
935 err = befs_init_inodecache();
936 if (err)
937 goto unacquire_none;
938
939 err = register_filesystem(&befs_fs_type);
940 if (err)
941 goto unacquire_inodecache;
942
943 return 0;
944
945unacquire_inodecache:
946 befs_destroy_inodecache();
947
948unacquire_none:
949 return err;
950}
951
952static void __exit
953exit_befs_fs(void)
954{
955 befs_destroy_inodecache();
956
957 unregister_filesystem(&befs_fs_type);
958}
959
960/*
961Macros that typecheck the init and exit functions,
962ensures that they are called at init and cleanup,
963and eliminates warnings about unused functions.
964*/
965module_init(init_befs_fs)
966module_exit(exit_befs_fs)
1/*
2 * linux/fs/befs/linuxvfs.c
3 *
4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
5 *
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/fs.h>
13#include <linux/errno.h>
14#include <linux/stat.h>
15#include <linux/nls.h>
16#include <linux/buffer_head.h>
17#include <linux/vfs.h>
18#include <linux/parser.h>
19#include <linux/namei.h>
20#include <linux/sched.h>
21
22#include "befs.h"
23#include "btree.h"
24#include "inode.h"
25#include "datastream.h"
26#include "super.h"
27#include "io.h"
28
29MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
30MODULE_AUTHOR("Will Dyson");
31MODULE_LICENSE("GPL");
32
33/* The units the vfs expects inode->i_blocks to be in */
34#define VFS_BLOCK_SIZE 512
35
36static int befs_readdir(struct file *, struct dir_context *);
37static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
38static int befs_readpage(struct file *file, struct page *page);
39static sector_t befs_bmap(struct address_space *mapping, sector_t block);
40static struct dentry *befs_lookup(struct inode *, struct dentry *, unsigned int);
41static struct inode *befs_iget(struct super_block *, unsigned long);
42static struct inode *befs_alloc_inode(struct super_block *sb);
43static void befs_destroy_inode(struct inode *inode);
44static void befs_destroy_inodecache(void);
45static void *befs_follow_link(struct dentry *, struct nameidata *);
46static void *befs_fast_follow_link(struct dentry *, struct nameidata *);
47static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
48 char **out, int *out_len);
49static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
50 char **out, int *out_len);
51static void befs_put_super(struct super_block *);
52static int befs_remount(struct super_block *, int *, char *);
53static int befs_statfs(struct dentry *, struct kstatfs *);
54static int parse_options(char *, befs_mount_options *);
55
56static const struct super_operations befs_sops = {
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 .show_options = generic_show_options,
63};
64
65/* slab cache for befs_inode_info objects */
66static struct kmem_cache *befs_inode_cachep;
67
68static const struct file_operations befs_dir_operations = {
69 .read = generic_read_dir,
70 .iterate = befs_readdir,
71 .llseek = generic_file_llseek,
72};
73
74static const struct inode_operations befs_dir_inode_operations = {
75 .lookup = befs_lookup,
76};
77
78static const struct address_space_operations befs_aops = {
79 .readpage = befs_readpage,
80 .bmap = befs_bmap,
81};
82
83static const struct inode_operations befs_fast_symlink_inode_operations = {
84 .readlink = generic_readlink,
85 .follow_link = befs_fast_follow_link,
86};
87
88static const struct inode_operations befs_symlink_inode_operations = {
89 .readlink = generic_readlink,
90 .follow_link = befs_follow_link,
91 .put_link = kfree_put_link,
92};
93
94/*
95 * Called by generic_file_read() to read a page of data
96 *
97 * In turn, simply calls a generic block read function and
98 * passes it the address of befs_get_block, for mapping file
99 * positions to disk blocks.
100 */
101static int
102befs_readpage(struct file *file, struct page *page)
103{
104 return block_read_full_page(page, befs_get_block);
105}
106
107static sector_t
108befs_bmap(struct address_space *mapping, sector_t block)
109{
110 return generic_block_bmap(mapping, block, befs_get_block);
111}
112
113/*
114 * Generic function to map a file position (block) to a
115 * disk offset (passed back in bh_result).
116 *
117 * Used by many higher level functions.
118 *
119 * Calls befs_fblock2brun() in datastream.c to do the real work.
120 *
121 * -WD 10-26-01
122 */
123
124static int
125befs_get_block(struct inode *inode, sector_t block,
126 struct buffer_head *bh_result, int create)
127{
128 struct super_block *sb = inode->i_sb;
129 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
130 befs_block_run run = BAD_IADDR;
131 int res = 0;
132 ulong disk_off;
133
134 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
135 (unsigned long)inode->i_ino, (long)block);
136
137 if (block < 0) {
138 befs_error(sb, "befs_get_block() was asked for a block "
139 "number less than zero: block %ld in inode %lu",
140 (long)block, (unsigned long)inode->i_ino);
141 return -EIO;
142 }
143
144 if (create) {
145 befs_error(sb, "befs_get_block() was asked to write to "
146 "block %ld in inode %lu", (long)block,
147 (unsigned long)inode->i_ino);
148 return -EPERM;
149 }
150
151 res = befs_fblock2brun(sb, ds, block, &run);
152 if (res != BEFS_OK) {
153 befs_error(sb,
154 "<--- %s for inode %lu, block %ld ERROR",
155 __func__, (unsigned long)inode->i_ino,
156 (long)block);
157 return -EFBIG;
158 }
159
160 disk_off = (ulong) iaddr2blockno(sb, &run);
161
162 map_bh(bh_result, inode->i_sb, disk_off);
163
164 befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu",
165 __func__, (unsigned long)inode->i_ino, (long)block,
166 (unsigned long)disk_off);
167
168 return 0;
169}
170
171static struct dentry *
172befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
173{
174 struct inode *inode = NULL;
175 struct super_block *sb = dir->i_sb;
176 befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
177 befs_off_t offset;
178 int ret;
179 int utfnamelen;
180 char *utfname;
181 const char *name = dentry->d_name.name;
182
183 befs_debug(sb, "---> %s name %s inode %ld", __func__,
184 dentry->d_name.name, dir->i_ino);
185
186 /* Convert to UTF-8 */
187 if (BEFS_SB(sb)->nls) {
188 ret =
189 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
190 if (ret < 0) {
191 befs_debug(sb, "<--- %s ERROR", __func__);
192 return ERR_PTR(ret);
193 }
194 ret = befs_btree_find(sb, ds, utfname, &offset);
195 kfree(utfname);
196
197 } else {
198 ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
199 }
200
201 if (ret == BEFS_BT_NOT_FOUND) {
202 befs_debug(sb, "<--- %s %s not found", __func__,
203 dentry->d_name.name);
204 return ERR_PTR(-ENOENT);
205
206 } else if (ret != BEFS_OK || offset == 0) {
207 befs_warning(sb, "<--- %s Error", __func__);
208 return ERR_PTR(-ENODATA);
209 }
210
211 inode = befs_iget(dir->i_sb, (ino_t) offset);
212 if (IS_ERR(inode))
213 return ERR_CAST(inode);
214
215 d_add(dentry, inode);
216
217 befs_debug(sb, "<--- %s", __func__);
218
219 return NULL;
220}
221
222static int
223befs_readdir(struct file *file, struct dir_context *ctx)
224{
225 struct inode *inode = file_inode(file);
226 struct super_block *sb = inode->i_sb;
227 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
228 befs_off_t value;
229 int result;
230 size_t keysize;
231 unsigned char d_type;
232 char keybuf[BEFS_NAME_LEN + 1];
233 const char *dirname = file->f_path.dentry->d_name.name;
234
235 befs_debug(sb, "---> %s name %s, inode %ld, ctx->pos %lld",
236 __func__, dirname, inode->i_ino, ctx->pos);
237
238more:
239 result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,
240 keybuf, &keysize, &value);
241
242 if (result == BEFS_ERR) {
243 befs_debug(sb, "<--- %s ERROR", __func__);
244 befs_error(sb, "IO error reading %s (inode %lu)",
245 dirname, inode->i_ino);
246 return -EIO;
247
248 } else if (result == BEFS_BT_END) {
249 befs_debug(sb, "<--- %s END", __func__);
250 return 0;
251
252 } else if (result == BEFS_BT_EMPTY) {
253 befs_debug(sb, "<--- %s Empty directory", __func__);
254 return 0;
255 }
256
257 d_type = DT_UNKNOWN;
258
259 /* Convert to NLS */
260 if (BEFS_SB(sb)->nls) {
261 char *nlsname;
262 int nlsnamelen;
263 result =
264 befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
265 if (result < 0) {
266 befs_debug(sb, "<--- %s ERROR", __func__);
267 return result;
268 }
269 if (!dir_emit(ctx, nlsname, nlsnamelen,
270 (ino_t) value, d_type)) {
271 kfree(nlsname);
272 return 0;
273 }
274 kfree(nlsname);
275 } else {
276 if (!dir_emit(ctx, keybuf, keysize,
277 (ino_t) value, d_type))
278 return 0;
279 }
280 ctx->pos++;
281 goto more;
282
283 befs_debug(sb, "<--- %s pos %lld", __func__, ctx->pos);
284
285 return 0;
286}
287
288static struct inode *
289befs_alloc_inode(struct super_block *sb)
290{
291 struct befs_inode_info *bi;
292 bi = (struct befs_inode_info *)kmem_cache_alloc(befs_inode_cachep,
293 GFP_KERNEL);
294 if (!bi)
295 return NULL;
296 return &bi->vfs_inode;
297}
298
299static void befs_i_callback(struct rcu_head *head)
300{
301 struct inode *inode = container_of(head, struct inode, i_rcu);
302 kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
303}
304
305static void befs_destroy_inode(struct inode *inode)
306{
307 call_rcu(&inode->i_rcu, befs_i_callback);
308}
309
310static void init_once(void *foo)
311{
312 struct befs_inode_info *bi = (struct befs_inode_info *) foo;
313
314 inode_init_once(&bi->vfs_inode);
315}
316
317static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
318{
319 struct buffer_head *bh = NULL;
320 befs_inode *raw_inode = NULL;
321
322 befs_sb_info *befs_sb = BEFS_SB(sb);
323 befs_inode_info *befs_ino = NULL;
324 struct inode *inode;
325 long ret = -EIO;
326
327 befs_debug(sb, "---> %s inode = %lu", __func__, ino);
328
329 inode = iget_locked(sb, ino);
330 if (!inode)
331 return ERR_PTR(-ENOMEM);
332 if (!(inode->i_state & I_NEW))
333 return inode;
334
335 befs_ino = BEFS_I(inode);
336
337 /* convert from vfs's inode number to befs's inode number */
338 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
339
340 befs_debug(sb, " real inode number [%u, %hu, %hu]",
341 befs_ino->i_inode_num.allocation_group,
342 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
343
344 bh = befs_bread(sb, inode->i_ino);
345 if (!bh) {
346 befs_error(sb, "unable to read inode block - "
347 "inode = %lu", inode->i_ino);
348 goto unacquire_none;
349 }
350
351 raw_inode = (befs_inode *) bh->b_data;
352
353 befs_dump_inode(sb, raw_inode);
354
355 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
356 befs_error(sb, "Bad inode: %lu", inode->i_ino);
357 goto unacquire_bh;
358 }
359
360 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
361
362 /*
363 * set uid and gid. But since current BeOS is single user OS, so
364 * you can change by "uid" or "gid" options.
365 */
366
367 inode->i_uid = befs_sb->mount_opts.use_uid ?
368 befs_sb->mount_opts.uid :
369 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
370 inode->i_gid = befs_sb->mount_opts.use_gid ?
371 befs_sb->mount_opts.gid :
372 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
373
374 set_nlink(inode, 1);
375
376 /*
377 * BEFS's time is 64 bits, but current VFS is 32 bits...
378 * BEFS don't have access time. Nor inode change time. VFS
379 * doesn't have creation time.
380 * Also, the lower 16 bits of the last_modified_time and
381 * create_time are just a counter to help ensure uniqueness
382 * for indexing purposes. (PFD, page 54)
383 */
384
385 inode->i_mtime.tv_sec =
386 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
387 inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */
388 inode->i_ctime = inode->i_mtime;
389 inode->i_atime = inode->i_mtime;
390
391 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
392 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
393 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
394 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
395
396 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
397 inode->i_size = 0;
398 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
399 strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
400 BEFS_SYMLINK_LEN - 1);
401 befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
402 } else {
403 int num_blks;
404
405 befs_ino->i_data.ds =
406 fsds_to_cpu(sb, &raw_inode->data.datastream);
407
408 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
409 inode->i_blocks =
410 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
411 inode->i_size = befs_ino->i_data.ds.size;
412 }
413
414 inode->i_mapping->a_ops = &befs_aops;
415
416 if (S_ISREG(inode->i_mode)) {
417 inode->i_fop = &generic_ro_fops;
418 } else if (S_ISDIR(inode->i_mode)) {
419 inode->i_op = &befs_dir_inode_operations;
420 inode->i_fop = &befs_dir_operations;
421 } else if (S_ISLNK(inode->i_mode)) {
422 if (befs_ino->i_flags & BEFS_LONG_SYMLINK)
423 inode->i_op = &befs_symlink_inode_operations;
424 else
425 inode->i_op = &befs_fast_symlink_inode_operations;
426 } else {
427 befs_error(sb, "Inode %lu is not a regular file, "
428 "directory or symlink. THAT IS WRONG! BeFS has no "
429 "on disk special files", inode->i_ino);
430 goto unacquire_bh;
431 }
432
433 brelse(bh);
434 befs_debug(sb, "<--- %s", __func__);
435 unlock_new_inode(inode);
436 return inode;
437
438 unacquire_bh:
439 brelse(bh);
440
441 unacquire_none:
442 iget_failed(inode);
443 befs_debug(sb, "<--- %s - Bad inode", __func__);
444 return ERR_PTR(ret);
445}
446
447/* Initialize the inode cache. Called at fs setup.
448 *
449 * Taken from NFS implementation by Al Viro.
450 */
451static int __init
452befs_init_inodecache(void)
453{
454 befs_inode_cachep = kmem_cache_create("befs_inode_cache",
455 sizeof (struct befs_inode_info),
456 0, (SLAB_RECLAIM_ACCOUNT|
457 SLAB_MEM_SPREAD),
458 init_once);
459 if (befs_inode_cachep == NULL) {
460 pr_err("%s: Couldn't initialize inode slabcache\n", __func__);
461 return -ENOMEM;
462 }
463 return 0;
464}
465
466/* Called at fs teardown.
467 *
468 * Taken from NFS implementation by Al Viro.
469 */
470static void
471befs_destroy_inodecache(void)
472{
473 /*
474 * Make sure all delayed rcu free inodes are flushed before we
475 * destroy cache.
476 */
477 rcu_barrier();
478 kmem_cache_destroy(befs_inode_cachep);
479}
480
481/*
482 * The inode of symbolic link is different to data stream.
483 * The data stream become link name. Unless the LONG_SYMLINK
484 * flag is set.
485 */
486static void *
487befs_follow_link(struct dentry *dentry, struct nameidata *nd)
488{
489 struct super_block *sb = dentry->d_sb;
490 befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
491 befs_data_stream *data = &befs_ino->i_data.ds;
492 befs_off_t len = data->size;
493 char *link;
494
495 if (len == 0) {
496 befs_error(sb, "Long symlink with illegal length");
497 link = ERR_PTR(-EIO);
498 } else {
499 befs_debug(sb, "Follow long symlink");
500
501 link = kmalloc(len, GFP_NOFS);
502 if (!link) {
503 link = ERR_PTR(-ENOMEM);
504 } else if (befs_read_lsymlink(sb, data, link, len) != len) {
505 kfree(link);
506 befs_error(sb, "Failed to read entire long symlink");
507 link = ERR_PTR(-EIO);
508 } else {
509 link[len - 1] = '\0';
510 }
511 }
512 nd_set_link(nd, link);
513 return NULL;
514}
515
516
517static void *
518befs_fast_follow_link(struct dentry *dentry, struct nameidata *nd)
519{
520 befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
521 nd_set_link(nd, befs_ino->i_data.symlink);
522 return NULL;
523}
524
525/*
526 * UTF-8 to NLS charset convert routine
527 *
528 *
529 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
530 * the nls tables directly
531 */
532
533static int
534befs_utf2nls(struct super_block *sb, const char *in,
535 int in_len, char **out, int *out_len)
536{
537 struct nls_table *nls = BEFS_SB(sb)->nls;
538 int i, o;
539 unicode_t uni;
540 int unilen, utflen;
541 char *result;
542 /* The utf8->nls conversion won't make the final nls string bigger
543 * than the utf one, but if the string is pure ascii they'll have the
544 * same width and an extra char is needed to save the additional \0
545 */
546 int maxlen = in_len + 1;
547
548 befs_debug(sb, "---> %s", __func__);
549
550 if (!nls) {
551 befs_error(sb, "%s called with no NLS table loaded", __func__);
552 return -EINVAL;
553 }
554
555 *out = result = kmalloc(maxlen, GFP_NOFS);
556 if (!*out) {
557 befs_error(sb, "%s cannot allocate memory", __func__);
558 *out_len = 0;
559 return -ENOMEM;
560 }
561
562 for (i = o = 0; i < in_len; i += utflen, o += unilen) {
563
564 /* convert from UTF-8 to Unicode */
565 utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
566 if (utflen < 0)
567 goto conv_err;
568
569 /* convert from Unicode to nls */
570 if (uni > MAX_WCHAR_T)
571 goto conv_err;
572 unilen = nls->uni2char(uni, &result[o], in_len - o);
573 if (unilen < 0)
574 goto conv_err;
575 }
576 result[o] = '\0';
577 *out_len = o;
578
579 befs_debug(sb, "<--- %s", __func__);
580
581 return o;
582
583 conv_err:
584 befs_error(sb, "Name using character set %s contains a character that "
585 "cannot be converted to unicode.", nls->charset);
586 befs_debug(sb, "<--- %s", __func__);
587 kfree(result);
588 return -EILSEQ;
589}
590
591/**
592 * befs_nls2utf - Convert NLS string to utf8 encodeing
593 * @sb: Superblock
594 * @src: Input string buffer in NLS format
595 * @srclen: Length of input string in bytes
596 * @dest: The output string in UTF-8 format
597 * @destlen: Length of the output buffer
598 *
599 * Converts input string @src, which is in the format of the loaded NLS map,
600 * into a utf8 string.
601 *
602 * The destination string @dest is allocated by this function and the caller is
603 * responsible for freeing it with kfree()
604 *
605 * On return, *@destlen is the length of @dest in bytes.
606 *
607 * On success, the return value is the number of utf8 characters written to
608 * the output buffer @dest.
609 *
610 * On Failure, a negative number coresponding to the error code is returned.
611 */
612
613static int
614befs_nls2utf(struct super_block *sb, const char *in,
615 int in_len, char **out, int *out_len)
616{
617 struct nls_table *nls = BEFS_SB(sb)->nls;
618 int i, o;
619 wchar_t uni;
620 int unilen, utflen;
621 char *result;
622 /* There're nls characters that will translate to 3-chars-wide UTF-8
623 * characters, a additional byte is needed to save the final \0
624 * in special cases */
625 int maxlen = (3 * in_len) + 1;
626
627 befs_debug(sb, "---> %s\n", __func__);
628
629 if (!nls) {
630 befs_error(sb, "%s called with no NLS table loaded.",
631 __func__);
632 return -EINVAL;
633 }
634
635 *out = result = kmalloc(maxlen, GFP_NOFS);
636 if (!*out) {
637 befs_error(sb, "%s cannot allocate memory", __func__);
638 *out_len = 0;
639 return -ENOMEM;
640 }
641
642 for (i = o = 0; i < in_len; i += unilen, o += utflen) {
643
644 /* convert from nls to unicode */
645 unilen = nls->char2uni(&in[i], in_len - i, &uni);
646 if (unilen < 0)
647 goto conv_err;
648
649 /* convert from unicode to UTF-8 */
650 utflen = utf32_to_utf8(uni, &result[o], 3);
651 if (utflen <= 0)
652 goto conv_err;
653 }
654
655 result[o] = '\0';
656 *out_len = o;
657
658 befs_debug(sb, "<--- %s", __func__);
659
660 return i;
661
662 conv_err:
663 befs_error(sb, "Name using charecter set %s contains a charecter that "
664 "cannot be converted to unicode.", nls->charset);
665 befs_debug(sb, "<--- %s", __func__);
666 kfree(result);
667 return -EILSEQ;
668}
669
670/**
671 * Use the
672 *
673 */
674enum {
675 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
676};
677
678static const match_table_t befs_tokens = {
679 {Opt_uid, "uid=%d"},
680 {Opt_gid, "gid=%d"},
681 {Opt_charset, "iocharset=%s"},
682 {Opt_debug, "debug"},
683 {Opt_err, NULL}
684};
685
686static int
687parse_options(char *options, befs_mount_options * opts)
688{
689 char *p;
690 substring_t args[MAX_OPT_ARGS];
691 int option;
692 kuid_t uid;
693 kgid_t gid;
694
695 /* Initialize options */
696 opts->uid = GLOBAL_ROOT_UID;
697 opts->gid = GLOBAL_ROOT_GID;
698 opts->use_uid = 0;
699 opts->use_gid = 0;
700 opts->iocharset = NULL;
701 opts->debug = 0;
702
703 if (!options)
704 return 1;
705
706 while ((p = strsep(&options, ",")) != NULL) {
707 int token;
708 if (!*p)
709 continue;
710
711 token = match_token(p, befs_tokens, args);
712 switch (token) {
713 case Opt_uid:
714 if (match_int(&args[0], &option))
715 return 0;
716 uid = INVALID_UID;
717 if (option >= 0)
718 uid = make_kuid(current_user_ns(), option);
719 if (!uid_valid(uid)) {
720 pr_err("Invalid uid %d, "
721 "using default\n", option);
722 break;
723 }
724 opts->uid = uid;
725 opts->use_uid = 1;
726 break;
727 case Opt_gid:
728 if (match_int(&args[0], &option))
729 return 0;
730 gid = INVALID_GID;
731 if (option >= 0)
732 gid = make_kgid(current_user_ns(), option);
733 if (!gid_valid(gid)) {
734 pr_err("Invalid gid %d, "
735 "using default\n", option);
736 break;
737 }
738 opts->gid = gid;
739 opts->use_gid = 1;
740 break;
741 case Opt_charset:
742 kfree(opts->iocharset);
743 opts->iocharset = match_strdup(&args[0]);
744 if (!opts->iocharset) {
745 pr_err("allocation failure for "
746 "iocharset string\n");
747 return 0;
748 }
749 break;
750 case Opt_debug:
751 opts->debug = 1;
752 break;
753 default:
754 pr_err("Unrecognized mount option \"%s\" "
755 "or missing value\n", p);
756 return 0;
757 }
758 }
759 return 1;
760}
761
762/* This function has the responsibiltiy of getting the
763 * filesystem ready for unmounting.
764 * Basically, we free everything that we allocated in
765 * befs_read_inode
766 */
767static void
768befs_put_super(struct super_block *sb)
769{
770 kfree(BEFS_SB(sb)->mount_opts.iocharset);
771 BEFS_SB(sb)->mount_opts.iocharset = NULL;
772 unload_nls(BEFS_SB(sb)->nls);
773 kfree(sb->s_fs_info);
774 sb->s_fs_info = NULL;
775}
776
777/* Allocate private field of the superblock, fill it.
778 *
779 * Finish filling the public superblock fields
780 * Make the root directory
781 * Load a set of NLS translations if needed.
782 */
783static int
784befs_fill_super(struct super_block *sb, void *data, int silent)
785{
786 struct buffer_head *bh;
787 befs_sb_info *befs_sb;
788 befs_super_block *disk_sb;
789 struct inode *root;
790 long ret = -EINVAL;
791 const unsigned long sb_block = 0;
792 const off_t x86_sb_off = 512;
793
794 save_mount_options(sb, data);
795
796 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);
797 if (sb->s_fs_info == NULL) {
798 pr_err("(%s): Unable to allocate memory for private "
799 "portion of superblock. Bailing.\n", sb->s_id);
800 goto unacquire_none;
801 }
802 befs_sb = BEFS_SB(sb);
803
804 if (!parse_options((char *) data, &befs_sb->mount_opts)) {
805 befs_error(sb, "cannot parse mount options");
806 goto unacquire_priv_sbp;
807 }
808
809 befs_debug(sb, "---> %s", __func__);
810
811#ifndef CONFIG_BEFS_RW
812 if (!(sb->s_flags & MS_RDONLY)) {
813 befs_warning(sb,
814 "No write support. Marking filesystem read-only");
815 sb->s_flags |= MS_RDONLY;
816 }
817#endif /* CONFIG_BEFS_RW */
818
819 /*
820 * Set dummy blocksize to read super block.
821 * Will be set to real fs blocksize later.
822 *
823 * Linux 2.4.10 and later refuse to read blocks smaller than
824 * the hardsect size for the device. But we also need to read at
825 * least 1k to get the second 512 bytes of the volume.
826 * -WD 10-26-01
827 */
828 sb_min_blocksize(sb, 1024);
829
830 if (!(bh = sb_bread(sb, sb_block))) {
831 befs_error(sb, "unable to read superblock");
832 goto unacquire_priv_sbp;
833 }
834
835 /* account for offset of super block on x86 */
836 disk_sb = (befs_super_block *) bh->b_data;
837 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
838 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
839 befs_debug(sb, "Using PPC superblock location");
840 } else {
841 befs_debug(sb, "Using x86 superblock location");
842 disk_sb =
843 (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
844 }
845
846 if (befs_load_sb(sb, disk_sb) != BEFS_OK)
847 goto unacquire_bh;
848
849 befs_dump_super_block(sb, disk_sb);
850
851 brelse(bh);
852
853 if (befs_check_sb(sb) != BEFS_OK)
854 goto unacquire_priv_sbp;
855
856 if( befs_sb->num_blocks > ~((sector_t)0) ) {
857 befs_error(sb, "blocks count: %llu "
858 "is larger than the host can use",
859 befs_sb->num_blocks);
860 goto unacquire_priv_sbp;
861 }
862
863 /*
864 * set up enough so that it can read an inode
865 * Fill in kernel superblock fields from private sb
866 */
867 sb->s_magic = BEFS_SUPER_MAGIC;
868 /* Set real blocksize of fs */
869 sb_set_blocksize(sb, (ulong) befs_sb->block_size);
870 sb->s_op = &befs_sops;
871 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
872 if (IS_ERR(root)) {
873 ret = PTR_ERR(root);
874 goto unacquire_priv_sbp;
875 }
876 sb->s_root = d_make_root(root);
877 if (!sb->s_root) {
878 befs_error(sb, "get root inode failed");
879 goto unacquire_priv_sbp;
880 }
881
882 /* load nls library */
883 if (befs_sb->mount_opts.iocharset) {
884 befs_debug(sb, "Loading nls: %s",
885 befs_sb->mount_opts.iocharset);
886 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
887 if (!befs_sb->nls) {
888 befs_warning(sb, "Cannot load nls %s"
889 " loading default nls",
890 befs_sb->mount_opts.iocharset);
891 befs_sb->nls = load_nls_default();
892 }
893 /* load default nls if none is specified in mount options */
894 } else {
895 befs_debug(sb, "Loading default nls");
896 befs_sb->nls = load_nls_default();
897 }
898
899 return 0;
900/*****************/
901 unacquire_bh:
902 brelse(bh);
903
904 unacquire_priv_sbp:
905 kfree(befs_sb->mount_opts.iocharset);
906 kfree(sb->s_fs_info);
907
908 unacquire_none:
909 sb->s_fs_info = NULL;
910 return ret;
911}
912
913static int
914befs_remount(struct super_block *sb, int *flags, char *data)
915{
916 sync_filesystem(sb);
917 if (!(*flags & MS_RDONLY))
918 return -EINVAL;
919 return 0;
920}
921
922static int
923befs_statfs(struct dentry *dentry, struct kstatfs *buf)
924{
925 struct super_block *sb = dentry->d_sb;
926 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
927
928 befs_debug(sb, "---> %s", __func__);
929
930 buf->f_type = BEFS_SUPER_MAGIC;
931 buf->f_bsize = sb->s_blocksize;
932 buf->f_blocks = BEFS_SB(sb)->num_blocks;
933 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
934 buf->f_bavail = buf->f_bfree;
935 buf->f_files = 0; /* UNKNOWN */
936 buf->f_ffree = 0; /* UNKNOWN */
937 buf->f_fsid.val[0] = (u32)id;
938 buf->f_fsid.val[1] = (u32)(id >> 32);
939 buf->f_namelen = BEFS_NAME_LEN;
940
941 befs_debug(sb, "<--- %s", __func__);
942
943 return 0;
944}
945
946static struct dentry *
947befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
948 void *data)
949{
950 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
951}
952
953static struct file_system_type befs_fs_type = {
954 .owner = THIS_MODULE,
955 .name = "befs",
956 .mount = befs_mount,
957 .kill_sb = kill_block_super,
958 .fs_flags = FS_REQUIRES_DEV,
959};
960MODULE_ALIAS_FS("befs");
961
962static int __init
963init_befs_fs(void)
964{
965 int err;
966
967 pr_info("version: %s\n", BEFS_VERSION);
968
969 err = befs_init_inodecache();
970 if (err)
971 goto unacquire_none;
972
973 err = register_filesystem(&befs_fs_type);
974 if (err)
975 goto unacquire_inodecache;
976
977 return 0;
978
979unacquire_inodecache:
980 befs_destroy_inodecache();
981
982unacquire_none:
983 return err;
984}
985
986static void __exit
987exit_befs_fs(void)
988{
989 befs_destroy_inodecache();
990
991 unregister_filesystem(&befs_fs_type);
992}
993
994/*
995Macros that typecheck the init and exit functions,
996ensures that they are called at init and cleanup,
997and eliminates warnings about unused functions.
998*/
999module_init(init_befs_fs)
1000module_exit(exit_befs_fs)