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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#include <linux/exportfs.h>
22
23#include "befs.h"
24#include "btree.h"
25#include "inode.h"
26#include "datastream.h"
27#include "super.h"
28#include "io.h"
29
30MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
31MODULE_AUTHOR("Will Dyson");
32MODULE_LICENSE("GPL");
33
34/* The units the vfs expects inode->i_blocks to be in */
35#define VFS_BLOCK_SIZE 512
36
37static int befs_readdir(struct file *, struct dir_context *);
38static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
39static int befs_readpage(struct file *file, struct page *page);
40static sector_t befs_bmap(struct address_space *mapping, sector_t block);
41static struct dentry *befs_lookup(struct inode *, struct dentry *,
42 unsigned int);
43static struct inode *befs_iget(struct super_block *, unsigned long);
44static struct inode *befs_alloc_inode(struct super_block *sb);
45static void befs_destroy_inode(struct inode *inode);
46static void befs_destroy_inodecache(void);
47static int befs_symlink_readpage(struct file *, struct page *);
48static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
49 char **out, int *out_len);
50static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
51 char **out, int *out_len);
52static void befs_put_super(struct super_block *);
53static int befs_remount(struct super_block *, int *, char *);
54static int befs_statfs(struct dentry *, struct kstatfs *);
55static int parse_options(char *, struct befs_mount_options *);
56static struct dentry *befs_fh_to_dentry(struct super_block *sb,
57 struct fid *fid, int fh_len, int fh_type);
58static struct dentry *befs_fh_to_parent(struct super_block *sb,
59 struct fid *fid, int fh_len, int fh_type);
60
61static const struct super_operations befs_sops = {
62 .alloc_inode = befs_alloc_inode, /* allocate a new inode */
63 .destroy_inode = befs_destroy_inode, /* deallocate an inode */
64 .put_super = befs_put_super, /* uninit super */
65 .statfs = befs_statfs, /* statfs */
66 .remount_fs = befs_remount,
67 .show_options = generic_show_options,
68};
69
70/* slab cache for befs_inode_info objects */
71static struct kmem_cache *befs_inode_cachep;
72
73static const struct file_operations befs_dir_operations = {
74 .read = generic_read_dir,
75 .iterate_shared = befs_readdir,
76 .llseek = generic_file_llseek,
77};
78
79static const struct inode_operations befs_dir_inode_operations = {
80 .lookup = befs_lookup,
81};
82
83static const struct address_space_operations befs_aops = {
84 .readpage = befs_readpage,
85 .bmap = befs_bmap,
86};
87
88static const struct address_space_operations befs_symlink_aops = {
89 .readpage = befs_symlink_readpage,
90};
91
92static const struct export_operations befs_export_operations = {
93 .fh_to_dentry = befs_fh_to_dentry,
94 .fh_to_parent = befs_fh_to_parent,
95};
96
97/*
98 * Called by generic_file_read() to read a page of data
99 *
100 * In turn, simply calls a generic block read function and
101 * passes it the address of befs_get_block, for mapping file
102 * positions to disk blocks.
103 */
104static int
105befs_readpage(struct file *file, struct page *page)
106{
107 return block_read_full_page(page, befs_get_block);
108}
109
110static sector_t
111befs_bmap(struct address_space *mapping, sector_t block)
112{
113 return generic_block_bmap(mapping, block, befs_get_block);
114}
115
116/*
117 * Generic function to map a file position (block) to a
118 * disk offset (passed back in bh_result).
119 *
120 * Used by many higher level functions.
121 *
122 * Calls befs_fblock2brun() in datastream.c to do the real work.
123 */
124
125static int
126befs_get_block(struct inode *inode, sector_t block,
127 struct buffer_head *bh_result, int create)
128{
129 struct super_block *sb = inode->i_sb;
130 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
131 befs_block_run run = BAD_IADDR;
132 int res;
133 ulong disk_off;
134
135 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
136 (unsigned long)inode->i_ino, (long)block);
137 if (create) {
138 befs_error(sb, "befs_get_block() was asked to write to "
139 "block %ld in inode %lu", (long)block,
140 (unsigned long)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 "<--- %s for inode %lu, block %ld ERROR",
148 __func__, (unsigned long)inode->i_ino,
149 (long)block);
150 return -EFBIG;
151 }
152
153 disk_off = (ulong) iaddr2blockno(sb, &run);
154
155 map_bh(bh_result, inode->i_sb, disk_off);
156
157 befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu",
158 __func__, (unsigned long)inode->i_ino, (long)block,
159 (unsigned long)disk_off);
160
161 return 0;
162}
163
164static struct dentry *
165befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
166{
167 struct inode *inode;
168 struct super_block *sb = dir->i_sb;
169 const befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
170 befs_off_t offset;
171 int ret;
172 int utfnamelen;
173 char *utfname;
174 const char *name = dentry->d_name.name;
175
176 befs_debug(sb, "---> %s name %pd inode %ld", __func__,
177 dentry, dir->i_ino);
178
179 /* Convert to UTF-8 */
180 if (BEFS_SB(sb)->nls) {
181 ret =
182 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
183 if (ret < 0) {
184 befs_debug(sb, "<--- %s ERROR", __func__);
185 return ERR_PTR(ret);
186 }
187 ret = befs_btree_find(sb, ds, utfname, &offset);
188 kfree(utfname);
189
190 } else {
191 ret = befs_btree_find(sb, ds, name, &offset);
192 }
193
194 if (ret == BEFS_BT_NOT_FOUND) {
195 befs_debug(sb, "<--- %s %pd not found", __func__, dentry);
196 d_add(dentry, NULL);
197 return ERR_PTR(-ENOENT);
198
199 } else if (ret != BEFS_OK || offset == 0) {
200 befs_error(sb, "<--- %s Error", __func__);
201 return ERR_PTR(-ENODATA);
202 }
203
204 inode = befs_iget(dir->i_sb, (ino_t) offset);
205 if (IS_ERR(inode))
206 return ERR_CAST(inode);
207
208 d_add(dentry, inode);
209
210 befs_debug(sb, "<--- %s", __func__);
211
212 return NULL;
213}
214
215static int
216befs_readdir(struct file *file, struct dir_context *ctx)
217{
218 struct inode *inode = file_inode(file);
219 struct super_block *sb = inode->i_sb;
220 const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
221 befs_off_t value;
222 int result;
223 size_t keysize;
224 char keybuf[BEFS_NAME_LEN + 1];
225
226 befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld",
227 __func__, file, inode->i_ino, ctx->pos);
228
229 while (1) {
230 result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,
231 keybuf, &keysize, &value);
232
233 if (result == BEFS_ERR) {
234 befs_debug(sb, "<--- %s ERROR", __func__);
235 befs_error(sb, "IO error reading %pD (inode %lu)",
236 file, inode->i_ino);
237 return -EIO;
238
239 } else if (result == BEFS_BT_END) {
240 befs_debug(sb, "<--- %s END", __func__);
241 return 0;
242
243 } else if (result == BEFS_BT_EMPTY) {
244 befs_debug(sb, "<--- %s Empty directory", __func__);
245 return 0;
246 }
247
248 /* Convert to NLS */
249 if (BEFS_SB(sb)->nls) {
250 char *nlsname;
251 int nlsnamelen;
252
253 result =
254 befs_utf2nls(sb, keybuf, keysize, &nlsname,
255 &nlsnamelen);
256 if (result < 0) {
257 befs_debug(sb, "<--- %s ERROR", __func__);
258 return result;
259 }
260 if (!dir_emit(ctx, nlsname, nlsnamelen,
261 (ino_t) value, DT_UNKNOWN)) {
262 kfree(nlsname);
263 return 0;
264 }
265 kfree(nlsname);
266 } else {
267 if (!dir_emit(ctx, keybuf, keysize,
268 (ino_t) value, DT_UNKNOWN))
269 return 0;
270 }
271 ctx->pos++;
272 }
273}
274
275static struct inode *
276befs_alloc_inode(struct super_block *sb)
277{
278 struct befs_inode_info *bi;
279
280 bi = kmem_cache_alloc(befs_inode_cachep, GFP_KERNEL);
281 if (!bi)
282 return NULL;
283 return &bi->vfs_inode;
284}
285
286static void befs_i_callback(struct rcu_head *head)
287{
288 struct inode *inode = container_of(head, struct inode, i_rcu);
289 kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
290}
291
292static void befs_destroy_inode(struct inode *inode)
293{
294 call_rcu(&inode->i_rcu, befs_i_callback);
295}
296
297static void init_once(void *foo)
298{
299 struct befs_inode_info *bi = (struct befs_inode_info *) foo;
300
301 inode_init_once(&bi->vfs_inode);
302}
303
304static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
305{
306 struct buffer_head *bh;
307 befs_inode *raw_inode;
308 struct befs_sb_info *befs_sb = BEFS_SB(sb);
309 struct befs_inode_info *befs_ino;
310 struct inode *inode;
311
312 befs_debug(sb, "---> %s inode = %lu", __func__, ino);
313
314 inode = iget_locked(sb, ino);
315 if (!inode)
316 return ERR_PTR(-ENOMEM);
317 if (!(inode->i_state & I_NEW))
318 return inode;
319
320 befs_ino = BEFS_I(inode);
321
322 /* convert from vfs's inode number to befs's inode number */
323 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
324
325 befs_debug(sb, " real inode number [%u, %hu, %hu]",
326 befs_ino->i_inode_num.allocation_group,
327 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
328
329 bh = sb_bread(sb, inode->i_ino);
330 if (!bh) {
331 befs_error(sb, "unable to read inode block - "
332 "inode = %lu", inode->i_ino);
333 goto unacquire_none;
334 }
335
336 raw_inode = (befs_inode *) bh->b_data;
337
338 befs_dump_inode(sb, raw_inode);
339
340 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
341 befs_error(sb, "Bad inode: %lu", inode->i_ino);
342 goto unacquire_bh;
343 }
344
345 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
346
347 /*
348 * set uid and gid. But since current BeOS is single user OS, so
349 * you can change by "uid" or "gid" options.
350 */
351
352 inode->i_uid = befs_sb->mount_opts.use_uid ?
353 befs_sb->mount_opts.uid :
354 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
355 inode->i_gid = befs_sb->mount_opts.use_gid ?
356 befs_sb->mount_opts.gid :
357 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
358
359 set_nlink(inode, 1);
360
361 /*
362 * BEFS's time is 64 bits, but current VFS is 32 bits...
363 * BEFS don't have access time. Nor inode change time. VFS
364 * doesn't have creation time.
365 * Also, the lower 16 bits of the last_modified_time and
366 * create_time are just a counter to help ensure uniqueness
367 * for indexing purposes. (PFD, page 54)
368 */
369
370 inode->i_mtime.tv_sec =
371 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
372 inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */
373 inode->i_ctime = inode->i_mtime;
374 inode->i_atime = inode->i_mtime;
375
376 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
377 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
378 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
379 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
380
381 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
382 inode->i_size = 0;
383 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
384 strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
385 BEFS_SYMLINK_LEN);
386 } else {
387 int num_blks;
388
389 befs_ino->i_data.ds =
390 fsds_to_cpu(sb, &raw_inode->data.datastream);
391
392 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
393 inode->i_blocks =
394 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
395 inode->i_size = befs_ino->i_data.ds.size;
396 }
397
398 inode->i_mapping->a_ops = &befs_aops;
399
400 if (S_ISREG(inode->i_mode)) {
401 inode->i_fop = &generic_ro_fops;
402 } else if (S_ISDIR(inode->i_mode)) {
403 inode->i_op = &befs_dir_inode_operations;
404 inode->i_fop = &befs_dir_operations;
405 } else if (S_ISLNK(inode->i_mode)) {
406 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
407 inode->i_op = &page_symlink_inode_operations;
408 inode_nohighmem(inode);
409 inode->i_mapping->a_ops = &befs_symlink_aops;
410 } else {
411 inode->i_link = befs_ino->i_data.symlink;
412 inode->i_op = &simple_symlink_inode_operations;
413 }
414 } else {
415 befs_error(sb, "Inode %lu is not a regular file, "
416 "directory or symlink. THAT IS WRONG! BeFS has no "
417 "on disk special files", inode->i_ino);
418 goto unacquire_bh;
419 }
420
421 brelse(bh);
422 befs_debug(sb, "<--- %s", __func__);
423 unlock_new_inode(inode);
424 return inode;
425
426unacquire_bh:
427 brelse(bh);
428
429unacquire_none:
430 iget_failed(inode);
431 befs_debug(sb, "<--- %s - Bad inode", __func__);
432 return ERR_PTR(-EIO);
433}
434
435/* Initialize the inode cache. Called at fs setup.
436 *
437 * Taken from NFS implementation by Al Viro.
438 */
439static int __init
440befs_init_inodecache(void)
441{
442 befs_inode_cachep = kmem_cache_create("befs_inode_cache",
443 sizeof (struct befs_inode_info),
444 0, (SLAB_RECLAIM_ACCOUNT|
445 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
446 init_once);
447 if (befs_inode_cachep == NULL)
448 return -ENOMEM;
449
450 return 0;
451}
452
453/* Called at fs teardown.
454 *
455 * Taken from NFS implementation by Al Viro.
456 */
457static void
458befs_destroy_inodecache(void)
459{
460 /*
461 * Make sure all delayed rcu free inodes are flushed before we
462 * destroy cache.
463 */
464 rcu_barrier();
465 kmem_cache_destroy(befs_inode_cachep);
466}
467
468/*
469 * The inode of symbolic link is different to data stream.
470 * The data stream become link name. Unless the LONG_SYMLINK
471 * flag is set.
472 */
473static int befs_symlink_readpage(struct file *unused, struct page *page)
474{
475 struct inode *inode = page->mapping->host;
476 struct super_block *sb = inode->i_sb;
477 struct befs_inode_info *befs_ino = BEFS_I(inode);
478 befs_data_stream *data = &befs_ino->i_data.ds;
479 befs_off_t len = data->size;
480 char *link = page_address(page);
481
482 if (len == 0 || len > PAGE_SIZE) {
483 befs_error(sb, "Long symlink with illegal length");
484 goto fail;
485 }
486 befs_debug(sb, "Follow long symlink");
487
488 if (befs_read_lsymlink(sb, data, link, len) != len) {
489 befs_error(sb, "Failed to read entire long symlink");
490 goto fail;
491 }
492 link[len - 1] = '\0';
493 SetPageUptodate(page);
494 unlock_page(page);
495 return 0;
496fail:
497 SetPageError(page);
498 unlock_page(page);
499 return -EIO;
500}
501
502/*
503 * UTF-8 to NLS charset convert routine
504 *
505 * Uses uni2char() / char2uni() rather than the nls tables directly
506 */
507static int
508befs_utf2nls(struct super_block *sb, const char *in,
509 int in_len, char **out, int *out_len)
510{
511 struct nls_table *nls = BEFS_SB(sb)->nls;
512 int i, o;
513 unicode_t uni;
514 int unilen, utflen;
515 char *result;
516 /* The utf8->nls conversion won't make the final nls string bigger
517 * than the utf one, but if the string is pure ascii they'll have the
518 * same width and an extra char is needed to save the additional \0
519 */
520 int maxlen = in_len + 1;
521
522 befs_debug(sb, "---> %s", __func__);
523
524 if (!nls) {
525 befs_error(sb, "%s called with no NLS table loaded", __func__);
526 return -EINVAL;
527 }
528
529 *out = result = kmalloc(maxlen, GFP_NOFS);
530 if (!*out)
531 return -ENOMEM;
532
533 for (i = o = 0; i < in_len; i += utflen, o += unilen) {
534
535 /* convert from UTF-8 to Unicode */
536 utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
537 if (utflen < 0)
538 goto conv_err;
539
540 /* convert from Unicode to nls */
541 if (uni > MAX_WCHAR_T)
542 goto conv_err;
543 unilen = nls->uni2char(uni, &result[o], in_len - o);
544 if (unilen < 0)
545 goto conv_err;
546 }
547 result[o] = '\0';
548 *out_len = o;
549
550 befs_debug(sb, "<--- %s", __func__);
551
552 return o;
553
554conv_err:
555 befs_error(sb, "Name using character set %s contains a character that "
556 "cannot be converted to unicode.", nls->charset);
557 befs_debug(sb, "<--- %s", __func__);
558 kfree(result);
559 return -EILSEQ;
560}
561
562/**
563 * befs_nls2utf - Convert NLS string to utf8 encodeing
564 * @sb: Superblock
565 * @in: Input string buffer in NLS format
566 * @in_len: Length of input string in bytes
567 * @out: The output string in UTF-8 format
568 * @out_len: Length of the output buffer
569 *
570 * Converts input string @in, which is in the format of the loaded NLS map,
571 * into a utf8 string.
572 *
573 * The destination string @out is allocated by this function and the caller is
574 * responsible for freeing it with kfree()
575 *
576 * On return, *@out_len is the length of @out in bytes.
577 *
578 * On success, the return value is the number of utf8 characters written to
579 * the output buffer @out.
580 *
581 * On Failure, a negative number coresponding to the error code is returned.
582 */
583
584static int
585befs_nls2utf(struct super_block *sb, const char *in,
586 int in_len, char **out, int *out_len)
587{
588 struct nls_table *nls = BEFS_SB(sb)->nls;
589 int i, o;
590 wchar_t uni;
591 int unilen, utflen;
592 char *result;
593 /*
594 * There are nls characters that will translate to 3-chars-wide UTF-8
595 * characters, an additional byte is needed to save the final \0
596 * in special cases
597 */
598 int maxlen = (3 * in_len) + 1;
599
600 befs_debug(sb, "---> %s\n", __func__);
601
602 if (!nls) {
603 befs_error(sb, "%s called with no NLS table loaded.",
604 __func__);
605 return -EINVAL;
606 }
607
608 *out = result = kmalloc(maxlen, GFP_NOFS);
609 if (!*out) {
610 *out_len = 0;
611 return -ENOMEM;
612 }
613
614 for (i = o = 0; i < in_len; i += unilen, o += utflen) {
615
616 /* convert from nls to unicode */
617 unilen = nls->char2uni(&in[i], in_len - i, &uni);
618 if (unilen < 0)
619 goto conv_err;
620
621 /* convert from unicode to UTF-8 */
622 utflen = utf32_to_utf8(uni, &result[o], 3);
623 if (utflen <= 0)
624 goto conv_err;
625 }
626
627 result[o] = '\0';
628 *out_len = o;
629
630 befs_debug(sb, "<--- %s", __func__);
631
632 return i;
633
634conv_err:
635 befs_error(sb, "Name using character set %s contains a character that "
636 "cannot be converted to unicode.", nls->charset);
637 befs_debug(sb, "<--- %s", __func__);
638 kfree(result);
639 return -EILSEQ;
640}
641
642static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino,
643 uint32_t generation)
644{
645 /* No need to handle i_generation */
646 return befs_iget(sb, ino);
647}
648
649/*
650 * Map a NFS file handle to a corresponding dentry
651 */
652static struct dentry *befs_fh_to_dentry(struct super_block *sb,
653 struct fid *fid, int fh_len, int fh_type)
654{
655 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
656 befs_nfs_get_inode);
657}
658
659/*
660 * Find the parent for a file specified by NFS handle
661 */
662static struct dentry *befs_fh_to_parent(struct super_block *sb,
663 struct fid *fid, int fh_len, int fh_type)
664{
665 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
666 befs_nfs_get_inode);
667}
668
669enum {
670 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
671};
672
673static const match_table_t befs_tokens = {
674 {Opt_uid, "uid=%d"},
675 {Opt_gid, "gid=%d"},
676 {Opt_charset, "iocharset=%s"},
677 {Opt_debug, "debug"},
678 {Opt_err, NULL}
679};
680
681static int
682parse_options(char *options, struct befs_mount_options *opts)
683{
684 char *p;
685 substring_t args[MAX_OPT_ARGS];
686 int option;
687 kuid_t uid;
688 kgid_t gid;
689
690 /* Initialize options */
691 opts->uid = GLOBAL_ROOT_UID;
692 opts->gid = GLOBAL_ROOT_GID;
693 opts->use_uid = 0;
694 opts->use_gid = 0;
695 opts->iocharset = NULL;
696 opts->debug = 0;
697
698 if (!options)
699 return 1;
700
701 while ((p = strsep(&options, ",")) != NULL) {
702 int token;
703
704 if (!*p)
705 continue;
706
707 token = match_token(p, befs_tokens, args);
708 switch (token) {
709 case Opt_uid:
710 if (match_int(&args[0], &option))
711 return 0;
712 uid = INVALID_UID;
713 if (option >= 0)
714 uid = make_kuid(current_user_ns(), option);
715 if (!uid_valid(uid)) {
716 pr_err("Invalid uid %d, "
717 "using default\n", option);
718 break;
719 }
720 opts->uid = uid;
721 opts->use_uid = 1;
722 break;
723 case Opt_gid:
724 if (match_int(&args[0], &option))
725 return 0;
726 gid = INVALID_GID;
727 if (option >= 0)
728 gid = make_kgid(current_user_ns(), option);
729 if (!gid_valid(gid)) {
730 pr_err("Invalid gid %d, "
731 "using default\n", option);
732 break;
733 }
734 opts->gid = gid;
735 opts->use_gid = 1;
736 break;
737 case Opt_charset:
738 kfree(opts->iocharset);
739 opts->iocharset = match_strdup(&args[0]);
740 if (!opts->iocharset) {
741 pr_err("allocation failure for "
742 "iocharset string\n");
743 return 0;
744 }
745 break;
746 case Opt_debug:
747 opts->debug = 1;
748 break;
749 default:
750 pr_err("Unrecognized mount option \"%s\" "
751 "or missing value\n", p);
752 return 0;
753 }
754 }
755 return 1;
756}
757
758/* This function has the responsibiltiy of getting the
759 * filesystem ready for unmounting.
760 * Basically, we free everything that we allocated in
761 * befs_read_inode
762 */
763static void
764befs_put_super(struct super_block *sb)
765{
766 kfree(BEFS_SB(sb)->mount_opts.iocharset);
767 BEFS_SB(sb)->mount_opts.iocharset = NULL;
768 unload_nls(BEFS_SB(sb)->nls);
769 kfree(sb->s_fs_info);
770 sb->s_fs_info = NULL;
771}
772
773/* Allocate private field of the superblock, fill it.
774 *
775 * Finish filling the public superblock fields
776 * Make the root directory
777 * Load a set of NLS translations if needed.
778 */
779static int
780befs_fill_super(struct super_block *sb, void *data, int silent)
781{
782 struct buffer_head *bh;
783 struct befs_sb_info *befs_sb;
784 befs_super_block *disk_sb;
785 struct inode *root;
786 long ret = -EINVAL;
787 const unsigned long sb_block = 0;
788 const off_t x86_sb_off = 512;
789 int blocksize;
790
791 save_mount_options(sb, data);
792
793 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);
794 if (sb->s_fs_info == NULL)
795 goto unacquire_none;
796
797 befs_sb = BEFS_SB(sb);
798
799 if (!parse_options((char *) data, &befs_sb->mount_opts)) {
800 if (!silent)
801 befs_error(sb, "cannot parse mount options");
802 goto unacquire_priv_sbp;
803 }
804
805 befs_debug(sb, "---> %s", __func__);
806
807 if (!(sb->s_flags & MS_RDONLY)) {
808 befs_warning(sb,
809 "No write support. Marking filesystem read-only");
810 sb->s_flags |= MS_RDONLY;
811 }
812
813 /*
814 * Set dummy blocksize to read super block.
815 * Will be set to real fs blocksize later.
816 *
817 * Linux 2.4.10 and later refuse to read blocks smaller than
818 * the logical block size for the device. But we also need to read at
819 * least 1k to get the second 512 bytes of the volume.
820 */
821 blocksize = sb_min_blocksize(sb, 1024);
822 if (!blocksize) {
823 if (!silent)
824 befs_error(sb, "unable to set blocksize");
825 goto unacquire_priv_sbp;
826 }
827
828 bh = sb_bread(sb, sb_block);
829 if (!bh) {
830 if (!silent)
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 (befs_check_sb(sb) != BEFS_OK))
848 goto unacquire_bh;
849
850 befs_dump_super_block(sb, disk_sb);
851
852 brelse(bh);
853
854 if (befs_sb->num_blocks > ~((sector_t)0)) {
855 if (!silent)
856 befs_error(sb, "blocks count: %llu is larger than the host can use",
857 befs_sb->num_blocks);
858 goto unacquire_priv_sbp;
859 }
860
861 /*
862 * set up enough so that it can read an inode
863 * Fill in kernel superblock fields from private sb
864 */
865 sb->s_magic = BEFS_SUPER_MAGIC;
866 /* Set real blocksize of fs */
867 sb_set_blocksize(sb, (ulong) befs_sb->block_size);
868 sb->s_op = &befs_sops;
869 sb->s_export_op = &befs_export_operations;
870 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
871 if (IS_ERR(root)) {
872 ret = PTR_ERR(root);
873 goto unacquire_priv_sbp;
874 }
875 sb->s_root = d_make_root(root);
876 if (!sb->s_root) {
877 if (!silent)
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
901unacquire_bh:
902 brelse(bh);
903
904unacquire_priv_sbp:
905 kfree(befs_sb->mount_opts.iocharset);
906 kfree(sb->s_fs_info);
907 sb->s_fs_info = NULL;
908
909unacquire_none:
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/*
995 * Macros that typecheck the init and exit functions,
996 * ensures that they are called at init and cleanup,
997 * and eliminates warnings about unused functions.
998 */
999module_init(init_befs_fs)
1000module_exit(exit_befs_fs)