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1/*
2 * linux/fs/befs/linuxvfs.c
3 *
4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
5 *
6 */
7
8#include <linux/module.h>
9#include <linux/slab.h>
10#include <linux/fs.h>
11#include <linux/errno.h>
12#include <linux/stat.h>
13#include <linux/nls.h>
14#include <linux/buffer_head.h>
15#include <linux/vfs.h>
16#include <linux/parser.h>
17#include <linux/namei.h>
18
19#include "befs.h"
20#include "btree.h"
21#include "inode.h"
22#include "datastream.h"
23#include "super.h"
24#include "io.h"
25
26MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
27MODULE_AUTHOR("Will Dyson");
28MODULE_LICENSE("GPL");
29
30/* The units the vfs expects inode->i_blocks to be in */
31#define VFS_BLOCK_SIZE 512
32
33static int befs_readdir(struct file *, void *, filldir_t);
34static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
35static int befs_readpage(struct file *file, struct page *page);
36static sector_t befs_bmap(struct address_space *mapping, sector_t block);
37static struct dentry *befs_lookup(struct inode *, struct dentry *, struct nameidata *);
38static struct inode *befs_iget(struct super_block *, unsigned long);
39static struct inode *befs_alloc_inode(struct super_block *sb);
40static void befs_destroy_inode(struct inode *inode);
41static int befs_init_inodecache(void);
42static void befs_destroy_inodecache(void);
43static void *befs_follow_link(struct dentry *, struct nameidata *);
44static void befs_put_link(struct dentry *, struct nameidata *, void *);
45static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
46 char **out, int *out_len);
47static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
48 char **out, int *out_len);
49static void befs_put_super(struct super_block *);
50static int befs_remount(struct super_block *, int *, char *);
51static int befs_statfs(struct dentry *, struct kstatfs *);
52static int parse_options(char *, befs_mount_options *);
53
54static const struct super_operations befs_sops = {
55 .alloc_inode = befs_alloc_inode, /* allocate a new inode */
56 .destroy_inode = befs_destroy_inode, /* deallocate an inode */
57 .put_super = befs_put_super, /* uninit super */
58 .statfs = befs_statfs, /* statfs */
59 .remount_fs = befs_remount,
60 .show_options = generic_show_options,
61};
62
63/* slab cache for befs_inode_info objects */
64static struct kmem_cache *befs_inode_cachep;
65
66static const struct file_operations befs_dir_operations = {
67 .read = generic_read_dir,
68 .readdir = befs_readdir,
69 .llseek = generic_file_llseek,
70};
71
72static const struct inode_operations befs_dir_inode_operations = {
73 .lookup = befs_lookup,
74};
75
76static const struct address_space_operations befs_aops = {
77 .readpage = befs_readpage,
78 .bmap = befs_bmap,
79};
80
81static const struct inode_operations befs_symlink_inode_operations = {
82 .readlink = generic_readlink,
83 .follow_link = befs_follow_link,
84 .put_link = befs_put_link,
85};
86
87/*
88 * Called by generic_file_read() to read a page of data
89 *
90 * In turn, simply calls a generic block read function and
91 * passes it the address of befs_get_block, for mapping file
92 * positions to disk blocks.
93 */
94static int
95befs_readpage(struct file *file, struct page *page)
96{
97 return block_read_full_page(page, befs_get_block);
98}
99
100static sector_t
101befs_bmap(struct address_space *mapping, sector_t block)
102{
103 return generic_block_bmap(mapping, block, befs_get_block);
104}
105
106/*
107 * Generic function to map a file position (block) to a
108 * disk offset (passed back in bh_result).
109 *
110 * Used by many higher level functions.
111 *
112 * Calls befs_fblock2brun() in datastream.c to do the real work.
113 *
114 * -WD 10-26-01
115 */
116
117static int
118befs_get_block(struct inode *inode, sector_t block,
119 struct buffer_head *bh_result, int create)
120{
121 struct super_block *sb = inode->i_sb;
122 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
123 befs_block_run run = BAD_IADDR;
124 int res = 0;
125 ulong disk_off;
126
127 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
128 inode->i_ino, block);
129
130 if (block < 0) {
131 befs_error(sb, "befs_get_block() was asked for a block "
132 "number less than zero: block %ld in inode %lu",
133 block, inode->i_ino);
134 return -EIO;
135 }
136
137 if (create) {
138 befs_error(sb, "befs_get_block() was asked to write to "
139 "block %ld in inode %lu", block, inode->i_ino);
140 return -EPERM;
141 }
142
143 res = befs_fblock2brun(sb, ds, block, &run);
144 if (res != BEFS_OK) {
145 befs_error(sb,
146 "<--- befs_get_block() for inode %lu, block "
147 "%ld ERROR", inode->i_ino, block);
148 return -EFBIG;
149 }
150
151 disk_off = (ulong) iaddr2blockno(sb, &run);
152
153 map_bh(bh_result, inode->i_sb, disk_off);
154
155 befs_debug(sb, "<--- befs_get_block() for inode %lu, block %ld, "
156 "disk address %lu", inode->i_ino, block, disk_off);
157
158 return 0;
159}
160
161static struct dentry *
162befs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
163{
164 struct inode *inode = NULL;
165 struct super_block *sb = dir->i_sb;
166 befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
167 befs_off_t offset;
168 int ret;
169 int utfnamelen;
170 char *utfname;
171 const char *name = dentry->d_name.name;
172
173 befs_debug(sb, "---> befs_lookup() "
174 "name %s inode %ld", dentry->d_name.name, dir->i_ino);
175
176 /* Convert to UTF-8 */
177 if (BEFS_SB(sb)->nls) {
178 ret =
179 befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
180 if (ret < 0) {
181 befs_debug(sb, "<--- befs_lookup() ERROR");
182 return ERR_PTR(ret);
183 }
184 ret = befs_btree_find(sb, ds, utfname, &offset);
185 kfree(utfname);
186
187 } else {
188 ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
189 }
190
191 if (ret == BEFS_BT_NOT_FOUND) {
192 befs_debug(sb, "<--- befs_lookup() %s not found",
193 dentry->d_name.name);
194 return ERR_PTR(-ENOENT);
195
196 } else if (ret != BEFS_OK || offset == 0) {
197 befs_warning(sb, "<--- befs_lookup() Error");
198 return ERR_PTR(-ENODATA);
199 }
200
201 inode = befs_iget(dir->i_sb, (ino_t) offset);
202 if (IS_ERR(inode))
203 return ERR_CAST(inode);
204
205 d_add(dentry, inode);
206
207 befs_debug(sb, "<--- befs_lookup()");
208
209 return NULL;
210}
211
212static int
213befs_readdir(struct file *filp, void *dirent, filldir_t filldir)
214{
215 struct inode *inode = filp->f_path.dentry->d_inode;
216 struct super_block *sb = inode->i_sb;
217 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
218 befs_off_t value;
219 int result;
220 size_t keysize;
221 unsigned char d_type;
222 char keybuf[BEFS_NAME_LEN + 1];
223 char *nlsname;
224 int nlsnamelen;
225 const char *dirname = filp->f_path.dentry->d_name.name;
226
227 befs_debug(sb, "---> befs_readdir() "
228 "name %s, inode %ld, filp->f_pos %Ld",
229 dirname, inode->i_ino, filp->f_pos);
230
231 result = befs_btree_read(sb, ds, filp->f_pos, BEFS_NAME_LEN + 1,
232 keybuf, &keysize, &value);
233
234 if (result == BEFS_ERR) {
235 befs_debug(sb, "<--- befs_readdir() ERROR");
236 befs_error(sb, "IO error reading %s (inode %lu)",
237 dirname, inode->i_ino);
238 return -EIO;
239
240 } else if (result == BEFS_BT_END) {
241 befs_debug(sb, "<--- befs_readdir() END");
242 return 0;
243
244 } else if (result == BEFS_BT_EMPTY) {
245 befs_debug(sb, "<--- befs_readdir() Empty directory");
246 return 0;
247 }
248
249 d_type = DT_UNKNOWN;
250
251 /* Convert to NLS */
252 if (BEFS_SB(sb)->nls) {
253 result =
254 befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
255 if (result < 0) {
256 befs_debug(sb, "<--- befs_readdir() ERROR");
257 return result;
258 }
259 result = filldir(dirent, nlsname, nlsnamelen, filp->f_pos,
260 (ino_t) value, d_type);
261 kfree(nlsname);
262
263 } else {
264 result = filldir(dirent, keybuf, keysize, filp->f_pos,
265 (ino_t) value, d_type);
266 }
267
268 filp->f_pos++;
269
270 befs_debug(sb, "<--- befs_readdir() filp->f_pos %Ld", filp->f_pos);
271
272 return 0;
273}
274
275static struct inode *
276befs_alloc_inode(struct super_block *sb)
277{
278 struct befs_inode_info *bi;
279 bi = (struct befs_inode_info *)kmem_cache_alloc(befs_inode_cachep,
280 GFP_KERNEL);
281 if (!bi)
282 return NULL;
283 return &bi->vfs_inode;
284}
285
286static void befs_i_callback(struct rcu_head *head)
287{
288 struct inode *inode = container_of(head, struct inode, i_rcu);
289 INIT_LIST_HEAD(&inode->i_dentry);
290 kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
291}
292
293static void befs_destroy_inode(struct inode *inode)
294{
295 call_rcu(&inode->i_rcu, befs_i_callback);
296}
297
298static void init_once(void *foo)
299{
300 struct befs_inode_info *bi = (struct befs_inode_info *) foo;
301
302 inode_init_once(&bi->vfs_inode);
303}
304
305static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
306{
307 struct buffer_head *bh = NULL;
308 befs_inode *raw_inode = NULL;
309
310 befs_sb_info *befs_sb = BEFS_SB(sb);
311 befs_inode_info *befs_ino = NULL;
312 struct inode *inode;
313 long ret = -EIO;
314
315 befs_debug(sb, "---> befs_read_inode() " "inode = %lu", ino);
316
317 inode = iget_locked(sb, ino);
318 if (IS_ERR(inode))
319 return inode;
320 if (!(inode->i_state & I_NEW))
321 return inode;
322
323 befs_ino = BEFS_I(inode);
324
325 /* convert from vfs's inode number to befs's inode number */
326 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
327
328 befs_debug(sb, " real inode number [%u, %hu, %hu]",
329 befs_ino->i_inode_num.allocation_group,
330 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
331
332 bh = befs_bread(sb, inode->i_ino);
333 if (!bh) {
334 befs_error(sb, "unable to read inode block - "
335 "inode = %lu", inode->i_ino);
336 goto unacquire_none;
337 }
338
339 raw_inode = (befs_inode *) bh->b_data;
340
341 befs_dump_inode(sb, raw_inode);
342
343 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
344 befs_error(sb, "Bad inode: %lu", inode->i_ino);
345 goto unacquire_bh;
346 }
347
348 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
349
350 /*
351 * set uid and gid. But since current BeOS is single user OS, so
352 * you can change by "uid" or "gid" options.
353 */
354
355 inode->i_uid = befs_sb->mount_opts.use_uid ?
356 befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
357 inode->i_gid = befs_sb->mount_opts.use_gid ?
358 befs_sb->mount_opts.gid : (gid_t) fs32_to_cpu(sb, raw_inode->gid);
359
360 inode->i_nlink = 1;
361
362 /*
363 * BEFS's time is 64 bits, but current VFS is 32 bits...
364 * BEFS don't have access time. Nor inode change time. VFS
365 * doesn't have creation time.
366 * Also, the lower 16 bits of the last_modified_time and
367 * create_time are just a counter to help ensure uniqueness
368 * for indexing purposes. (PFD, page 54)
369 */
370
371 inode->i_mtime.tv_sec =
372 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
373 inode->i_mtime.tv_nsec = 0; /* lower 16 bits are not a time */
374 inode->i_ctime = inode->i_mtime;
375 inode->i_atime = inode->i_mtime;
376
377 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
378 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
379 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
380 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
381
382 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
383 inode->i_size = 0;
384 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
385 strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
386 BEFS_SYMLINK_LEN - 1);
387 befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
388 } else {
389 int num_blks;
390
391 befs_ino->i_data.ds =
392 fsds_to_cpu(sb, &raw_inode->data.datastream);
393
394 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
395 inode->i_blocks =
396 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
397 inode->i_size = befs_ino->i_data.ds.size;
398 }
399
400 inode->i_mapping->a_ops = &befs_aops;
401
402 if (S_ISREG(inode->i_mode)) {
403 inode->i_fop = &generic_ro_fops;
404 } else if (S_ISDIR(inode->i_mode)) {
405 inode->i_op = &befs_dir_inode_operations;
406 inode->i_fop = &befs_dir_operations;
407 } else if (S_ISLNK(inode->i_mode)) {
408 inode->i_op = &befs_symlink_inode_operations;
409 } else {
410 befs_error(sb, "Inode %lu is not a regular file, "
411 "directory or symlink. THAT IS WRONG! BeFS has no "
412 "on disk special files", inode->i_ino);
413 goto unacquire_bh;
414 }
415
416 brelse(bh);
417 befs_debug(sb, "<--- befs_read_inode()");
418 unlock_new_inode(inode);
419 return inode;
420
421 unacquire_bh:
422 brelse(bh);
423
424 unacquire_none:
425 iget_failed(inode);
426 befs_debug(sb, "<--- befs_read_inode() - Bad inode");
427 return ERR_PTR(ret);
428}
429
430/* Initialize the inode cache. Called at fs setup.
431 *
432 * Taken from NFS implementation by Al Viro.
433 */
434static int
435befs_init_inodecache(void)
436{
437 befs_inode_cachep = kmem_cache_create("befs_inode_cache",
438 sizeof (struct befs_inode_info),
439 0, (SLAB_RECLAIM_ACCOUNT|
440 SLAB_MEM_SPREAD),
441 init_once);
442 if (befs_inode_cachep == NULL) {
443 printk(KERN_ERR "befs_init_inodecache: "
444 "Couldn't initialize inode slabcache\n");
445 return -ENOMEM;
446 }
447
448 return 0;
449}
450
451/* Called at fs teardown.
452 *
453 * Taken from NFS implementation by Al Viro.
454 */
455static void
456befs_destroy_inodecache(void)
457{
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 void *
467befs_follow_link(struct dentry *dentry, struct nameidata *nd)
468{
469 befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
470 char *link;
471
472 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
473 struct super_block *sb = dentry->d_sb;
474 befs_data_stream *data = &befs_ino->i_data.ds;
475 befs_off_t len = data->size;
476
477 if (len == 0) {
478 befs_error(sb, "Long symlink with illegal length");
479 link = ERR_PTR(-EIO);
480 } else {
481 befs_debug(sb, "Follow long symlink");
482
483 link = kmalloc(len, GFP_NOFS);
484 if (!link) {
485 link = ERR_PTR(-ENOMEM);
486 } else if (befs_read_lsymlink(sb, data, link, len) != len) {
487 kfree(link);
488 befs_error(sb, "Failed to read entire long symlink");
489 link = ERR_PTR(-EIO);
490 } else {
491 link[len - 1] = '\0';
492 }
493 }
494 } else {
495 link = befs_ino->i_data.symlink;
496 }
497
498 nd_set_link(nd, link);
499 return NULL;
500}
501
502static void befs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
503{
504 befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
505 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
506 char *link = nd_get_link(nd);
507 if (!IS_ERR(link))
508 kfree(link);
509 }
510}
511
512/*
513 * UTF-8 to NLS charset convert routine
514 *
515 *
516 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
517 * the nls tables directly
518 */
519
520static int
521befs_utf2nls(struct super_block *sb, const char *in,
522 int in_len, char **out, int *out_len)
523{
524 struct nls_table *nls = BEFS_SB(sb)->nls;
525 int i, o;
526 unicode_t uni;
527 int unilen, utflen;
528 char *result;
529 /* The utf8->nls conversion won't make the final nls string bigger
530 * than the utf one, but if the string is pure ascii they'll have the
531 * same width and an extra char is needed to save the additional \0
532 */
533 int maxlen = in_len + 1;
534
535 befs_debug(sb, "---> utf2nls()");
536
537 if (!nls) {
538 befs_error(sb, "befs_utf2nls called with no NLS table loaded");
539 return -EINVAL;
540 }
541
542 *out = result = kmalloc(maxlen, GFP_NOFS);
543 if (!*out) {
544 befs_error(sb, "befs_utf2nls() cannot allocate memory");
545 *out_len = 0;
546 return -ENOMEM;
547 }
548
549 for (i = o = 0; i < in_len; i += utflen, o += unilen) {
550
551 /* convert from UTF-8 to Unicode */
552 utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
553 if (utflen < 0)
554 goto conv_err;
555
556 /* convert from Unicode to nls */
557 if (uni > MAX_WCHAR_T)
558 goto conv_err;
559 unilen = nls->uni2char(uni, &result[o], in_len - o);
560 if (unilen < 0)
561 goto conv_err;
562 }
563 result[o] = '\0';
564 *out_len = o;
565
566 befs_debug(sb, "<--- utf2nls()");
567
568 return o;
569
570 conv_err:
571 befs_error(sb, "Name using character set %s contains a character that "
572 "cannot be converted to unicode.", nls->charset);
573 befs_debug(sb, "<--- utf2nls()");
574 kfree(result);
575 return -EILSEQ;
576}
577
578/**
579 * befs_nls2utf - Convert NLS string to utf8 encodeing
580 * @sb: Superblock
581 * @src: Input string buffer in NLS format
582 * @srclen: Length of input string in bytes
583 * @dest: The output string in UTF-8 format
584 * @destlen: Length of the output buffer
585 *
586 * Converts input string @src, which is in the format of the loaded NLS map,
587 * into a utf8 string.
588 *
589 * The destination string @dest is allocated by this function and the caller is
590 * responsible for freeing it with kfree()
591 *
592 * On return, *@destlen is the length of @dest in bytes.
593 *
594 * On success, the return value is the number of utf8 characters written to
595 * the output buffer @dest.
596 *
597 * On Failure, a negative number coresponding to the error code is returned.
598 */
599
600static int
601befs_nls2utf(struct super_block *sb, const char *in,
602 int in_len, char **out, int *out_len)
603{
604 struct nls_table *nls = BEFS_SB(sb)->nls;
605 int i, o;
606 wchar_t uni;
607 int unilen, utflen;
608 char *result;
609 /* There're nls characters that will translate to 3-chars-wide UTF-8
610 * characters, a additional byte is needed to save the final \0
611 * in special cases */
612 int maxlen = (3 * in_len) + 1;
613
614 befs_debug(sb, "---> nls2utf()\n");
615
616 if (!nls) {
617 befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
618 return -EINVAL;
619 }
620
621 *out = result = kmalloc(maxlen, GFP_NOFS);
622 if (!*out) {
623 befs_error(sb, "befs_nls2utf() cannot allocate memory");
624 *out_len = 0;
625 return -ENOMEM;
626 }
627
628 for (i = o = 0; i < in_len; i += unilen, o += utflen) {
629
630 /* convert from nls to unicode */
631 unilen = nls->char2uni(&in[i], in_len - i, &uni);
632 if (unilen < 0)
633 goto conv_err;
634
635 /* convert from unicode to UTF-8 */
636 utflen = utf32_to_utf8(uni, &result[o], 3);
637 if (utflen <= 0)
638 goto conv_err;
639 }
640
641 result[o] = '\0';
642 *out_len = o;
643
644 befs_debug(sb, "<--- nls2utf()");
645
646 return i;
647
648 conv_err:
649 befs_error(sb, "Name using charecter set %s contains a charecter that "
650 "cannot be converted to unicode.", nls->charset);
651 befs_debug(sb, "<--- nls2utf()");
652 kfree(result);
653 return -EILSEQ;
654}
655
656/**
657 * Use the
658 *
659 */
660enum {
661 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
662};
663
664static const match_table_t befs_tokens = {
665 {Opt_uid, "uid=%d"},
666 {Opt_gid, "gid=%d"},
667 {Opt_charset, "iocharset=%s"},
668 {Opt_debug, "debug"},
669 {Opt_err, NULL}
670};
671
672static int
673parse_options(char *options, befs_mount_options * opts)
674{
675 char *p;
676 substring_t args[MAX_OPT_ARGS];
677 int option;
678
679 /* Initialize options */
680 opts->uid = 0;
681 opts->gid = 0;
682 opts->use_uid = 0;
683 opts->use_gid = 0;
684 opts->iocharset = NULL;
685 opts->debug = 0;
686
687 if (!options)
688 return 1;
689
690 while ((p = strsep(&options, ",")) != NULL) {
691 int token;
692 if (!*p)
693 continue;
694
695 token = match_token(p, befs_tokens, args);
696 switch (token) {
697 case Opt_uid:
698 if (match_int(&args[0], &option))
699 return 0;
700 if (option < 0) {
701 printk(KERN_ERR "BeFS: Invalid uid %d, "
702 "using default\n", option);
703 break;
704 }
705 opts->uid = option;
706 opts->use_uid = 1;
707 break;
708 case Opt_gid:
709 if (match_int(&args[0], &option))
710 return 0;
711 if (option < 0) {
712 printk(KERN_ERR "BeFS: Invalid gid %d, "
713 "using default\n", option);
714 break;
715 }
716 opts->gid = option;
717 opts->use_gid = 1;
718 break;
719 case Opt_charset:
720 kfree(opts->iocharset);
721 opts->iocharset = match_strdup(&args[0]);
722 if (!opts->iocharset) {
723 printk(KERN_ERR "BeFS: allocation failure for "
724 "iocharset string\n");
725 return 0;
726 }
727 break;
728 case Opt_debug:
729 opts->debug = 1;
730 break;
731 default:
732 printk(KERN_ERR "BeFS: Unrecognized mount option \"%s\" "
733 "or missing value\n", p);
734 return 0;
735 }
736 }
737 return 1;
738}
739
740/* This function has the responsibiltiy of getting the
741 * filesystem ready for unmounting.
742 * Basically, we free everything that we allocated in
743 * befs_read_inode
744 */
745static void
746befs_put_super(struct super_block *sb)
747{
748 kfree(BEFS_SB(sb)->mount_opts.iocharset);
749 BEFS_SB(sb)->mount_opts.iocharset = NULL;
750 unload_nls(BEFS_SB(sb)->nls);
751 kfree(sb->s_fs_info);
752 sb->s_fs_info = NULL;
753}
754
755/* Allocate private field of the superblock, fill it.
756 *
757 * Finish filling the public superblock fields
758 * Make the root directory
759 * Load a set of NLS translations if needed.
760 */
761static int
762befs_fill_super(struct super_block *sb, void *data, int silent)
763{
764 struct buffer_head *bh;
765 befs_sb_info *befs_sb;
766 befs_super_block *disk_sb;
767 struct inode *root;
768 long ret = -EINVAL;
769 const unsigned long sb_block = 0;
770 const off_t x86_sb_off = 512;
771
772 save_mount_options(sb, data);
773
774 sb->s_fs_info = kmalloc(sizeof (*befs_sb), GFP_KERNEL);
775 if (sb->s_fs_info == NULL) {
776 printk(KERN_ERR
777 "BeFS(%s): Unable to allocate memory for private "
778 "portion of superblock. Bailing.\n", sb->s_id);
779 goto unacquire_none;
780 }
781 befs_sb = BEFS_SB(sb);
782 memset(befs_sb, 0, sizeof(befs_sb_info));
783
784 if (!parse_options((char *) data, &befs_sb->mount_opts)) {
785 befs_error(sb, "cannot parse mount options");
786 goto unacquire_priv_sbp;
787 }
788
789 befs_debug(sb, "---> befs_fill_super()");
790
791#ifndef CONFIG_BEFS_RW
792 if (!(sb->s_flags & MS_RDONLY)) {
793 befs_warning(sb,
794 "No write support. Marking filesystem read-only");
795 sb->s_flags |= MS_RDONLY;
796 }
797#endif /* CONFIG_BEFS_RW */
798
799 /*
800 * Set dummy blocksize to read super block.
801 * Will be set to real fs blocksize later.
802 *
803 * Linux 2.4.10 and later refuse to read blocks smaller than
804 * the hardsect size for the device. But we also need to read at
805 * least 1k to get the second 512 bytes of the volume.
806 * -WD 10-26-01
807 */
808 sb_min_blocksize(sb, 1024);
809
810 if (!(bh = sb_bread(sb, sb_block))) {
811 befs_error(sb, "unable to read superblock");
812 goto unacquire_priv_sbp;
813 }
814
815 /* account for offset of super block on x86 */
816 disk_sb = (befs_super_block *) bh->b_data;
817 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
818 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
819 befs_debug(sb, "Using PPC superblock location");
820 } else {
821 befs_debug(sb, "Using x86 superblock location");
822 disk_sb =
823 (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
824 }
825
826 if (befs_load_sb(sb, disk_sb) != BEFS_OK)
827 goto unacquire_bh;
828
829 befs_dump_super_block(sb, disk_sb);
830
831 brelse(bh);
832
833 if (befs_check_sb(sb) != BEFS_OK)
834 goto unacquire_priv_sbp;
835
836 if( befs_sb->num_blocks > ~((sector_t)0) ) {
837 befs_error(sb, "blocks count: %Lu "
838 "is larger than the host can use",
839 befs_sb->num_blocks);
840 goto unacquire_priv_sbp;
841 }
842
843 /*
844 * set up enough so that it can read an inode
845 * Fill in kernel superblock fields from private sb
846 */
847 sb->s_magic = BEFS_SUPER_MAGIC;
848 /* Set real blocksize of fs */
849 sb_set_blocksize(sb, (ulong) befs_sb->block_size);
850 sb->s_op = &befs_sops;
851 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
852 if (IS_ERR(root)) {
853 ret = PTR_ERR(root);
854 goto unacquire_priv_sbp;
855 }
856 sb->s_root = d_alloc_root(root);
857 if (!sb->s_root) {
858 iput(root);
859 befs_error(sb, "get root inode failed");
860 goto unacquire_priv_sbp;
861 }
862
863 /* load nls library */
864 if (befs_sb->mount_opts.iocharset) {
865 befs_debug(sb, "Loading nls: %s",
866 befs_sb->mount_opts.iocharset);
867 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
868 if (!befs_sb->nls) {
869 befs_warning(sb, "Cannot load nls %s"
870 " loading default nls",
871 befs_sb->mount_opts.iocharset);
872 befs_sb->nls = load_nls_default();
873 }
874 /* load default nls if none is specified in mount options */
875 } else {
876 befs_debug(sb, "Loading default nls");
877 befs_sb->nls = load_nls_default();
878 }
879
880 return 0;
881/*****************/
882 unacquire_bh:
883 brelse(bh);
884
885 unacquire_priv_sbp:
886 kfree(befs_sb->mount_opts.iocharset);
887 kfree(sb->s_fs_info);
888
889 unacquire_none:
890 sb->s_fs_info = NULL;
891 return ret;
892}
893
894static int
895befs_remount(struct super_block *sb, int *flags, char *data)
896{
897 if (!(*flags & MS_RDONLY))
898 return -EINVAL;
899 return 0;
900}
901
902static int
903befs_statfs(struct dentry *dentry, struct kstatfs *buf)
904{
905 struct super_block *sb = dentry->d_sb;
906 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
907
908 befs_debug(sb, "---> befs_statfs()");
909
910 buf->f_type = BEFS_SUPER_MAGIC;
911 buf->f_bsize = sb->s_blocksize;
912 buf->f_blocks = BEFS_SB(sb)->num_blocks;
913 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
914 buf->f_bavail = buf->f_bfree;
915 buf->f_files = 0; /* UNKNOWN */
916 buf->f_ffree = 0; /* UNKNOWN */
917 buf->f_fsid.val[0] = (u32)id;
918 buf->f_fsid.val[1] = (u32)(id >> 32);
919 buf->f_namelen = BEFS_NAME_LEN;
920
921 befs_debug(sb, "<--- befs_statfs()");
922
923 return 0;
924}
925
926static struct dentry *
927befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
928 void *data)
929{
930 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
931}
932
933static struct file_system_type befs_fs_type = {
934 .owner = THIS_MODULE,
935 .name = "befs",
936 .mount = befs_mount,
937 .kill_sb = kill_block_super,
938 .fs_flags = FS_REQUIRES_DEV,
939};
940
941static int __init
942init_befs_fs(void)
943{
944 int err;
945
946 printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
947
948 err = befs_init_inodecache();
949 if (err)
950 goto unacquire_none;
951
952 err = register_filesystem(&befs_fs_type);
953 if (err)
954 goto unacquire_inodecache;
955
956 return 0;
957
958unacquire_inodecache:
959 befs_destroy_inodecache();
960
961unacquire_none:
962 return err;
963}
964
965static void __exit
966exit_befs_fs(void)
967{
968 befs_destroy_inodecache();
969
970 unregister_filesystem(&befs_fs_type);
971}
972
973/*
974Macros that typecheck the init and exit functions,
975ensures that they are called at init and cleanup,
976and eliminates warnings about unused functions.
977*/
978module_init(init_befs_fs)
979module_exit(exit_befs_fs)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/fs/befs/linuxvfs.c
4 *
5 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
6 *
7 */
8
9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11#include <linux/module.h>
12#include <linux/slab.h>
13#include <linux/fs.h>
14#include <linux/errno.h>
15#include <linux/stat.h>
16#include <linux/nls.h>
17#include <linux/buffer_head.h>
18#include <linux/vfs.h>
19#include <linux/parser.h>
20#include <linux/namei.h>
21#include <linux/sched.h>
22#include <linux/cred.h>
23#include <linux/exportfs.h>
24#include <linux/seq_file.h>
25#include <linux/blkdev.h>
26
27#include "befs.h"
28#include "btree.h"
29#include "inode.h"
30#include "datastream.h"
31#include "super.h"
32#include "io.h"
33
34MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
35MODULE_AUTHOR("Will Dyson");
36MODULE_LICENSE("GPL");
37
38/* The units the vfs expects inode->i_blocks to be in */
39#define VFS_BLOCK_SIZE 512
40
41static int befs_readdir(struct file *, struct dir_context *);
42static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
43static int befs_read_folio(struct file *file, struct folio *folio);
44static sector_t befs_bmap(struct address_space *mapping, sector_t block);
45static struct dentry *befs_lookup(struct inode *, struct dentry *,
46 unsigned int);
47static struct inode *befs_iget(struct super_block *, unsigned long);
48static struct inode *befs_alloc_inode(struct super_block *sb);
49static void befs_free_inode(struct inode *inode);
50static void befs_destroy_inodecache(void);
51static int befs_symlink_read_folio(struct file *, struct folio *);
52static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
53 char **out, int *out_len);
54static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
55 char **out, int *out_len);
56static void befs_put_super(struct super_block *);
57static int befs_remount(struct super_block *, int *, char *);
58static int befs_statfs(struct dentry *, struct kstatfs *);
59static int befs_show_options(struct seq_file *, struct dentry *);
60static int parse_options(char *, struct befs_mount_options *);
61static struct dentry *befs_fh_to_dentry(struct super_block *sb,
62 struct fid *fid, int fh_len, int fh_type);
63static struct dentry *befs_fh_to_parent(struct super_block *sb,
64 struct fid *fid, int fh_len, int fh_type);
65static struct dentry *befs_get_parent(struct dentry *child);
66
67static const struct super_operations befs_sops = {
68 .alloc_inode = befs_alloc_inode, /* allocate a new inode */
69 .free_inode = befs_free_inode, /* deallocate an inode */
70 .put_super = befs_put_super, /* uninit super */
71 .statfs = befs_statfs, /* statfs */
72 .remount_fs = befs_remount,
73 .show_options = befs_show_options,
74};
75
76/* slab cache for befs_inode_info objects */
77static struct kmem_cache *befs_inode_cachep;
78
79static const struct file_operations befs_dir_operations = {
80 .read = generic_read_dir,
81 .iterate_shared = befs_readdir,
82 .llseek = generic_file_llseek,
83};
84
85static const struct inode_operations befs_dir_inode_operations = {
86 .lookup = befs_lookup,
87};
88
89static const struct address_space_operations befs_aops = {
90 .read_folio = befs_read_folio,
91 .bmap = befs_bmap,
92};
93
94static const struct address_space_operations befs_symlink_aops = {
95 .read_folio = befs_symlink_read_folio,
96};
97
98static const struct export_operations befs_export_operations = {
99 .encode_fh = generic_encode_ino32_fh,
100 .fh_to_dentry = befs_fh_to_dentry,
101 .fh_to_parent = befs_fh_to_parent,
102 .get_parent = befs_get_parent,
103};
104
105/*
106 * Called by generic_file_read() to read a folio of data
107 *
108 * In turn, simply calls a generic block read function and
109 * passes it the address of befs_get_block, for mapping file
110 * positions to disk blocks.
111 */
112static int befs_read_folio(struct file *file, struct folio *folio)
113{
114 return block_read_full_folio(folio, befs_get_block);
115}
116
117static sector_t
118befs_bmap(struct address_space *mapping, sector_t block)
119{
120 return generic_block_bmap(mapping, block, befs_get_block);
121}
122
123/*
124 * Generic function to map a file position (block) to a
125 * disk offset (passed back in bh_result).
126 *
127 * Used by many higher level functions.
128 *
129 * Calls befs_fblock2brun() in datastream.c to do the real work.
130 */
131
132static int
133befs_get_block(struct inode *inode, sector_t block,
134 struct buffer_head *bh_result, int create)
135{
136 struct super_block *sb = inode->i_sb;
137 befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
138 befs_block_run run = BAD_IADDR;
139 int res;
140 ulong disk_off;
141
142 befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
143 (unsigned long)inode->i_ino, (long)block);
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;
175 struct super_block *sb = dir->i_sb;
176 const 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 %pd inode %ld", __func__,
184 dentry, 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, name, &offset);
199 }
200
201 if (ret == BEFS_BT_NOT_FOUND) {
202 befs_debug(sb, "<--- %s %pd not found", __func__, dentry);
203 inode = NULL;
204 } else if (ret != BEFS_OK || offset == 0) {
205 befs_error(sb, "<--- %s Error", __func__);
206 inode = ERR_PTR(-ENODATA);
207 } else {
208 inode = befs_iget(dir->i_sb, (ino_t) offset);
209 }
210 befs_debug(sb, "<--- %s", __func__);
211
212 return d_splice_alias(inode, dentry);
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 = alloc_inode_sb(sb, befs_inode_cachep, GFP_KERNEL);
281 if (!bi)
282 return NULL;
283 return &bi->vfs_inode;
284}
285
286static void befs_free_inode(struct inode *inode)
287{
288 kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
289}
290
291static void init_once(void *foo)
292{
293 struct befs_inode_info *bi = (struct befs_inode_info *) foo;
294
295 inode_init_once(&bi->vfs_inode);
296}
297
298static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
299{
300 struct buffer_head *bh;
301 befs_inode *raw_inode;
302 struct befs_sb_info *befs_sb = BEFS_SB(sb);
303 struct befs_inode_info *befs_ino;
304 struct inode *inode;
305
306 befs_debug(sb, "---> %s inode = %lu", __func__, ino);
307
308 inode = iget_locked(sb, ino);
309 if (!inode)
310 return ERR_PTR(-ENOMEM);
311 if (!(inode->i_state & I_NEW))
312 return inode;
313
314 befs_ino = BEFS_I(inode);
315
316 /* convert from vfs's inode number to befs's inode number */
317 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
318
319 befs_debug(sb, " real inode number [%u, %hu, %hu]",
320 befs_ino->i_inode_num.allocation_group,
321 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
322
323 bh = sb_bread(sb, inode->i_ino);
324 if (!bh) {
325 befs_error(sb, "unable to read inode block - "
326 "inode = %lu", inode->i_ino);
327 goto unacquire_none;
328 }
329
330 raw_inode = (befs_inode *) bh->b_data;
331
332 befs_dump_inode(sb, raw_inode);
333
334 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
335 befs_error(sb, "Bad inode: %lu", inode->i_ino);
336 goto unacquire_bh;
337 }
338
339 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
340
341 /*
342 * set uid and gid. But since current BeOS is single user OS, so
343 * you can change by "uid" or "gid" options.
344 */
345
346 inode->i_uid = befs_sb->mount_opts.use_uid ?
347 befs_sb->mount_opts.uid :
348 make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
349 inode->i_gid = befs_sb->mount_opts.use_gid ?
350 befs_sb->mount_opts.gid :
351 make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
352
353 set_nlink(inode, 1);
354
355 /*
356 * BEFS's time is 64 bits, but current VFS is 32 bits...
357 * BEFS don't have access time. Nor inode change time. VFS
358 * doesn't have creation time.
359 * Also, the lower 16 bits of the last_modified_time and
360 * create_time are just a counter to help ensure uniqueness
361 * for indexing purposes. (PFD, page 54)
362 */
363
364 inode_set_mtime(inode,
365 fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16,
366 0);/* lower 16 bits are not a time */
367 inode_set_ctime_to_ts(inode, inode_get_mtime(inode));
368 inode_set_atime_to_ts(inode, inode_get_mtime(inode));
369
370 befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
371 befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
372 befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
373 befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
374
375 if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
376 inode->i_size = 0;
377 inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
378 strscpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
379 BEFS_SYMLINK_LEN);
380 } else {
381 int num_blks;
382
383 befs_ino->i_data.ds =
384 fsds_to_cpu(sb, &raw_inode->data.datastream);
385
386 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
387 inode->i_blocks =
388 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
389 inode->i_size = befs_ino->i_data.ds.size;
390 }
391
392 inode->i_mapping->a_ops = &befs_aops;
393
394 if (S_ISREG(inode->i_mode)) {
395 inode->i_fop = &generic_ro_fops;
396 } else if (S_ISDIR(inode->i_mode)) {
397 inode->i_op = &befs_dir_inode_operations;
398 inode->i_fop = &befs_dir_operations;
399 } else if (S_ISLNK(inode->i_mode)) {
400 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
401 inode->i_op = &page_symlink_inode_operations;
402 inode_nohighmem(inode);
403 inode->i_mapping->a_ops = &befs_symlink_aops;
404 } else {
405 inode->i_link = befs_ino->i_data.symlink;
406 inode->i_op = &simple_symlink_inode_operations;
407 }
408 } else {
409 befs_error(sb, "Inode %lu is not a regular file, "
410 "directory or symlink. THAT IS WRONG! BeFS has no "
411 "on disk special files", inode->i_ino);
412 goto unacquire_bh;
413 }
414
415 brelse(bh);
416 befs_debug(sb, "<--- %s", __func__);
417 unlock_new_inode(inode);
418 return inode;
419
420unacquire_bh:
421 brelse(bh);
422
423unacquire_none:
424 iget_failed(inode);
425 befs_debug(sb, "<--- %s - Bad inode", __func__);
426 return ERR_PTR(-EIO);
427}
428
429/* Initialize the inode cache. Called at fs setup.
430 *
431 * Taken from NFS implementation by Al Viro.
432 */
433static int __init
434befs_init_inodecache(void)
435{
436 befs_inode_cachep = kmem_cache_create_usercopy("befs_inode_cache",
437 sizeof(struct befs_inode_info), 0,
438 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
439 SLAB_ACCOUNT),
440 offsetof(struct befs_inode_info,
441 i_data.symlink),
442 sizeof_field(struct befs_inode_info,
443 i_data.symlink),
444 init_once);
445 if (befs_inode_cachep == NULL)
446 return -ENOMEM;
447
448 return 0;
449}
450
451/* Called at fs teardown.
452 *
453 * Taken from NFS implementation by Al Viro.
454 */
455static void
456befs_destroy_inodecache(void)
457{
458 /*
459 * Make sure all delayed rcu free inodes are flushed before we
460 * destroy cache.
461 */
462 rcu_barrier();
463 kmem_cache_destroy(befs_inode_cachep);
464}
465
466/*
467 * The inode of symbolic link is different to data stream.
468 * The data stream become link name. Unless the LONG_SYMLINK
469 * flag is set.
470 */
471static int befs_symlink_read_folio(struct file *unused, struct folio *folio)
472{
473 struct inode *inode = folio->mapping->host;
474 struct super_block *sb = inode->i_sb;
475 struct befs_inode_info *befs_ino = BEFS_I(inode);
476 befs_data_stream *data = &befs_ino->i_data.ds;
477 befs_off_t len = data->size;
478 char *link = folio_address(folio);
479
480 if (len == 0 || len > PAGE_SIZE) {
481 befs_error(sb, "Long symlink with illegal length");
482 goto fail;
483 }
484 befs_debug(sb, "Follow long symlink");
485
486 if (befs_read_lsymlink(sb, data, link, len) != len) {
487 befs_error(sb, "Failed to read entire long symlink");
488 goto fail;
489 }
490 link[len - 1] = '\0';
491 folio_mark_uptodate(folio);
492 folio_unlock(folio);
493 return 0;
494fail:
495 folio_set_error(folio);
496 folio_unlock(folio);
497 return -EIO;
498}
499
500/*
501 * UTF-8 to NLS charset convert routine
502 *
503 * Uses uni2char() / char2uni() rather than the nls tables directly
504 */
505static int
506befs_utf2nls(struct super_block *sb, const char *in,
507 int in_len, char **out, int *out_len)
508{
509 struct nls_table *nls = BEFS_SB(sb)->nls;
510 int i, o;
511 unicode_t uni;
512 int unilen, utflen;
513 char *result;
514 /* The utf8->nls conversion won't make the final nls string bigger
515 * than the utf one, but if the string is pure ascii they'll have the
516 * same width and an extra char is needed to save the additional \0
517 */
518 int maxlen = in_len + 1;
519
520 befs_debug(sb, "---> %s", __func__);
521
522 if (!nls) {
523 befs_error(sb, "%s called with no NLS table loaded", __func__);
524 return -EINVAL;
525 }
526
527 *out = result = kmalloc(maxlen, GFP_NOFS);
528 if (!*out)
529 return -ENOMEM;
530
531 for (i = o = 0; i < in_len; i += utflen, o += unilen) {
532
533 /* convert from UTF-8 to Unicode */
534 utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
535 if (utflen < 0)
536 goto conv_err;
537
538 /* convert from Unicode to nls */
539 if (uni > MAX_WCHAR_T)
540 goto conv_err;
541 unilen = nls->uni2char(uni, &result[o], in_len - o);
542 if (unilen < 0)
543 goto conv_err;
544 }
545 result[o] = '\0';
546 *out_len = o;
547
548 befs_debug(sb, "<--- %s", __func__);
549
550 return o;
551
552conv_err:
553 befs_error(sb, "Name using character set %s contains a character that "
554 "cannot be converted to unicode.", nls->charset);
555 befs_debug(sb, "<--- %s", __func__);
556 kfree(result);
557 return -EILSEQ;
558}
559
560/**
561 * befs_nls2utf - Convert NLS string to utf8 encodeing
562 * @sb: Superblock
563 * @in: Input string buffer in NLS format
564 * @in_len: Length of input string in bytes
565 * @out: The output string in UTF-8 format
566 * @out_len: Length of the output buffer
567 *
568 * Converts input string @in, which is in the format of the loaded NLS map,
569 * into a utf8 string.
570 *
571 * The destination string @out is allocated by this function and the caller is
572 * responsible for freeing it with kfree()
573 *
574 * On return, *@out_len is the length of @out in bytes.
575 *
576 * On success, the return value is the number of utf8 characters written to
577 * the output buffer @out.
578 *
579 * On Failure, a negative number coresponding to the error code is returned.
580 */
581
582static int
583befs_nls2utf(struct super_block *sb, const char *in,
584 int in_len, char **out, int *out_len)
585{
586 struct nls_table *nls = BEFS_SB(sb)->nls;
587 int i, o;
588 wchar_t uni;
589 int unilen, utflen;
590 char *result;
591 /*
592 * There are nls characters that will translate to 3-chars-wide UTF-8
593 * characters, an additional byte is needed to save the final \0
594 * in special cases
595 */
596 int maxlen = (3 * in_len) + 1;
597
598 befs_debug(sb, "---> %s\n", __func__);
599
600 if (!nls) {
601 befs_error(sb, "%s called with no NLS table loaded.",
602 __func__);
603 return -EINVAL;
604 }
605
606 *out = result = kmalloc(maxlen, GFP_NOFS);
607 if (!*out) {
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
632conv_err:
633 befs_error(sb, "Name using character set %s contains a character that "
634 "cannot be converted to unicode.", nls->charset);
635 befs_debug(sb, "<--- %s", __func__);
636 kfree(result);
637 return -EILSEQ;
638}
639
640static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino,
641 uint32_t generation)
642{
643 /* No need to handle i_generation */
644 return befs_iget(sb, ino);
645}
646
647/*
648 * Map a NFS file handle to a corresponding dentry
649 */
650static struct dentry *befs_fh_to_dentry(struct super_block *sb,
651 struct fid *fid, int fh_len, int fh_type)
652{
653 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
654 befs_nfs_get_inode);
655}
656
657/*
658 * Find the parent for a file specified by NFS handle
659 */
660static struct dentry *befs_fh_to_parent(struct super_block *sb,
661 struct fid *fid, int fh_len, int fh_type)
662{
663 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
664 befs_nfs_get_inode);
665}
666
667static struct dentry *befs_get_parent(struct dentry *child)
668{
669 struct inode *parent;
670 struct befs_inode_info *befs_ino = BEFS_I(d_inode(child));
671
672 parent = befs_iget(child->d_sb,
673 (unsigned long)befs_ino->i_parent.start);
674 return d_obtain_alias(parent);
675}
676
677enum {
678 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
679};
680
681static const match_table_t befs_tokens = {
682 {Opt_uid, "uid=%d"},
683 {Opt_gid, "gid=%d"},
684 {Opt_charset, "iocharset=%s"},
685 {Opt_debug, "debug"},
686 {Opt_err, NULL}
687};
688
689static int
690parse_options(char *options, struct befs_mount_options *opts)
691{
692 char *p;
693 substring_t args[MAX_OPT_ARGS];
694 int option;
695 kuid_t uid;
696 kgid_t gid;
697
698 /* Initialize options */
699 opts->uid = GLOBAL_ROOT_UID;
700 opts->gid = GLOBAL_ROOT_GID;
701 opts->use_uid = 0;
702 opts->use_gid = 0;
703 opts->iocharset = NULL;
704 opts->debug = 0;
705
706 if (!options)
707 return 1;
708
709 while ((p = strsep(&options, ",")) != NULL) {
710 int token;
711
712 if (!*p)
713 continue;
714
715 token = match_token(p, befs_tokens, args);
716 switch (token) {
717 case Opt_uid:
718 if (match_int(&args[0], &option))
719 return 0;
720 uid = INVALID_UID;
721 if (option >= 0)
722 uid = make_kuid(current_user_ns(), option);
723 if (!uid_valid(uid)) {
724 pr_err("Invalid uid %d, "
725 "using default\n", option);
726 break;
727 }
728 opts->uid = uid;
729 opts->use_uid = 1;
730 break;
731 case Opt_gid:
732 if (match_int(&args[0], &option))
733 return 0;
734 gid = INVALID_GID;
735 if (option >= 0)
736 gid = make_kgid(current_user_ns(), option);
737 if (!gid_valid(gid)) {
738 pr_err("Invalid gid %d, "
739 "using default\n", option);
740 break;
741 }
742 opts->gid = gid;
743 opts->use_gid = 1;
744 break;
745 case Opt_charset:
746 kfree(opts->iocharset);
747 opts->iocharset = match_strdup(&args[0]);
748 if (!opts->iocharset) {
749 pr_err("allocation failure for "
750 "iocharset string\n");
751 return 0;
752 }
753 break;
754 case Opt_debug:
755 opts->debug = 1;
756 break;
757 default:
758 pr_err("Unrecognized mount option \"%s\" "
759 "or missing value\n", p);
760 return 0;
761 }
762 }
763 return 1;
764}
765
766static int befs_show_options(struct seq_file *m, struct dentry *root)
767{
768 struct befs_sb_info *befs_sb = BEFS_SB(root->d_sb);
769 struct befs_mount_options *opts = &befs_sb->mount_opts;
770
771 if (!uid_eq(opts->uid, GLOBAL_ROOT_UID))
772 seq_printf(m, ",uid=%u",
773 from_kuid_munged(&init_user_ns, opts->uid));
774 if (!gid_eq(opts->gid, GLOBAL_ROOT_GID))
775 seq_printf(m, ",gid=%u",
776 from_kgid_munged(&init_user_ns, opts->gid));
777 if (opts->iocharset)
778 seq_printf(m, ",charset=%s", opts->iocharset);
779 if (opts->debug)
780 seq_puts(m, ",debug");
781 return 0;
782}
783
784/* This function has the responsibiltiy of getting the
785 * filesystem ready for unmounting.
786 * Basically, we free everything that we allocated in
787 * befs_read_inode
788 */
789static void
790befs_put_super(struct super_block *sb)
791{
792 kfree(BEFS_SB(sb)->mount_opts.iocharset);
793 BEFS_SB(sb)->mount_opts.iocharset = NULL;
794 unload_nls(BEFS_SB(sb)->nls);
795 kfree(sb->s_fs_info);
796 sb->s_fs_info = NULL;
797}
798
799/* Allocate private field of the superblock, fill it.
800 *
801 * Finish filling the public superblock fields
802 * Make the root directory
803 * Load a set of NLS translations if needed.
804 */
805static int
806befs_fill_super(struct super_block *sb, void *data, int silent)
807{
808 struct buffer_head *bh;
809 struct befs_sb_info *befs_sb;
810 befs_super_block *disk_sb;
811 struct inode *root;
812 long ret = -EINVAL;
813 const unsigned long sb_block = 0;
814 const off_t x86_sb_off = 512;
815 int blocksize;
816
817 sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);
818 if (sb->s_fs_info == NULL)
819 goto unacquire_none;
820
821 befs_sb = BEFS_SB(sb);
822
823 if (!parse_options((char *) data, &befs_sb->mount_opts)) {
824 if (!silent)
825 befs_error(sb, "cannot parse mount options");
826 goto unacquire_priv_sbp;
827 }
828
829 befs_debug(sb, "---> %s", __func__);
830
831 if (!sb_rdonly(sb)) {
832 befs_warning(sb,
833 "No write support. Marking filesystem read-only");
834 sb->s_flags |= SB_RDONLY;
835 }
836
837 /*
838 * Set dummy blocksize to read super block.
839 * Will be set to real fs blocksize later.
840 *
841 * Linux 2.4.10 and later refuse to read blocks smaller than
842 * the logical block size for the device. But we also need to read at
843 * least 1k to get the second 512 bytes of the volume.
844 */
845 blocksize = sb_min_blocksize(sb, 1024);
846 if (!blocksize) {
847 if (!silent)
848 befs_error(sb, "unable to set blocksize");
849 goto unacquire_priv_sbp;
850 }
851
852 bh = sb_bread(sb, sb_block);
853 if (!bh) {
854 if (!silent)
855 befs_error(sb, "unable to read superblock");
856 goto unacquire_priv_sbp;
857 }
858
859 /* account for offset of super block on x86 */
860 disk_sb = (befs_super_block *) bh->b_data;
861 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
862 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
863 befs_debug(sb, "Using PPC superblock location");
864 } else {
865 befs_debug(sb, "Using x86 superblock location");
866 disk_sb =
867 (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
868 }
869
870 if ((befs_load_sb(sb, disk_sb) != BEFS_OK) ||
871 (befs_check_sb(sb) != BEFS_OK))
872 goto unacquire_bh;
873
874 befs_dump_super_block(sb, disk_sb);
875
876 brelse(bh);
877
878 if (befs_sb->num_blocks > ~((sector_t)0)) {
879 if (!silent)
880 befs_error(sb, "blocks count: %llu is larger than the host can use",
881 befs_sb->num_blocks);
882 goto unacquire_priv_sbp;
883 }
884
885 /*
886 * set up enough so that it can read an inode
887 * Fill in kernel superblock fields from private sb
888 */
889 sb->s_magic = BEFS_SUPER_MAGIC;
890 /* Set real blocksize of fs */
891 sb_set_blocksize(sb, (ulong) befs_sb->block_size);
892 sb->s_op = &befs_sops;
893 sb->s_export_op = &befs_export_operations;
894 sb->s_time_min = 0;
895 sb->s_time_max = 0xffffffffffffll;
896 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
897 if (IS_ERR(root)) {
898 ret = PTR_ERR(root);
899 goto unacquire_priv_sbp;
900 }
901 sb->s_root = d_make_root(root);
902 if (!sb->s_root) {
903 if (!silent)
904 befs_error(sb, "get root inode failed");
905 goto unacquire_priv_sbp;
906 }
907
908 /* load nls library */
909 if (befs_sb->mount_opts.iocharset) {
910 befs_debug(sb, "Loading nls: %s",
911 befs_sb->mount_opts.iocharset);
912 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
913 if (!befs_sb->nls) {
914 befs_warning(sb, "Cannot load nls %s"
915 " loading default nls",
916 befs_sb->mount_opts.iocharset);
917 befs_sb->nls = load_nls_default();
918 }
919 /* load default nls if none is specified in mount options */
920 } else {
921 befs_debug(sb, "Loading default nls");
922 befs_sb->nls = load_nls_default();
923 }
924
925 return 0;
926
927unacquire_bh:
928 brelse(bh);
929
930unacquire_priv_sbp:
931 kfree(befs_sb->mount_opts.iocharset);
932 kfree(sb->s_fs_info);
933 sb->s_fs_info = NULL;
934
935unacquire_none:
936 return ret;
937}
938
939static int
940befs_remount(struct super_block *sb, int *flags, char *data)
941{
942 sync_filesystem(sb);
943 if (!(*flags & SB_RDONLY))
944 return -EINVAL;
945 return 0;
946}
947
948static int
949befs_statfs(struct dentry *dentry, struct kstatfs *buf)
950{
951 struct super_block *sb = dentry->d_sb;
952 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
953
954 befs_debug(sb, "---> %s", __func__);
955
956 buf->f_type = BEFS_SUPER_MAGIC;
957 buf->f_bsize = sb->s_blocksize;
958 buf->f_blocks = BEFS_SB(sb)->num_blocks;
959 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
960 buf->f_bavail = buf->f_bfree;
961 buf->f_files = 0; /* UNKNOWN */
962 buf->f_ffree = 0; /* UNKNOWN */
963 buf->f_fsid = u64_to_fsid(id);
964 buf->f_namelen = BEFS_NAME_LEN;
965
966 befs_debug(sb, "<--- %s", __func__);
967
968 return 0;
969}
970
971static struct dentry *
972befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
973 void *data)
974{
975 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
976}
977
978static struct file_system_type befs_fs_type = {
979 .owner = THIS_MODULE,
980 .name = "befs",
981 .mount = befs_mount,
982 .kill_sb = kill_block_super,
983 .fs_flags = FS_REQUIRES_DEV,
984};
985MODULE_ALIAS_FS("befs");
986
987static int __init
988init_befs_fs(void)
989{
990 int err;
991
992 pr_info("version: %s\n", BEFS_VERSION);
993
994 err = befs_init_inodecache();
995 if (err)
996 goto unacquire_none;
997
998 err = register_filesystem(&befs_fs_type);
999 if (err)
1000 goto unacquire_inodecache;
1001
1002 return 0;
1003
1004unacquire_inodecache:
1005 befs_destroy_inodecache();
1006
1007unacquire_none:
1008 return err;
1009}
1010
1011static void __exit
1012exit_befs_fs(void)
1013{
1014 befs_destroy_inodecache();
1015
1016 unregister_filesystem(&befs_fs_type);
1017}
1018
1019/*
1020 * Macros that typecheck the init and exit functions,
1021 * ensures that they are called at init and cleanup,
1022 * and eliminates warnings about unused functions.
1023 */
1024module_init(init_befs_fs)
1025module_exit(exit_befs_fs)