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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 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 = NULL;
307 befs_inode *raw_inode = NULL;
308
309 befs_sb_info *befs_sb = BEFS_SB(sb);
310 befs_inode_info *befs_ino = NULL;
311 struct inode *inode;
312 long ret = -EIO;
313
314 befs_debug(sb, "---> befs_read_inode() " "inode = %lu", ino);
315
316 inode = iget_locked(sb, ino);
317 if (IS_ERR(inode))
318 return inode;
319 if (!(inode->i_state & I_NEW))
320 return inode;
321
322 befs_ino = BEFS_I(inode);
323
324 /* convert from vfs's inode number to befs's inode number */
325 befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
326
327 befs_debug(sb, " real inode number [%u, %hu, %hu]",
328 befs_ino->i_inode_num.allocation_group,
329 befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
330
331 bh = befs_bread(sb, inode->i_ino);
332 if (!bh) {
333 befs_error(sb, "unable to read inode block - "
334 "inode = %lu", inode->i_ino);
335 goto unacquire_none;
336 }
337
338 raw_inode = (befs_inode *) bh->b_data;
339
340 befs_dump_inode(sb, raw_inode);
341
342 if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
343 befs_error(sb, "Bad inode: %lu", inode->i_ino);
344 goto unacquire_bh;
345 }
346
347 inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
348
349 /*
350 * set uid and gid. But since current BeOS is single user OS, so
351 * you can change by "uid" or "gid" options.
352 */
353
354 inode->i_uid = befs_sb->mount_opts.use_uid ?
355 befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
356 inode->i_gid = befs_sb->mount_opts.use_gid ?
357 befs_sb->mount_opts.gid : (gid_t) 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 strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
385 BEFS_SYMLINK_LEN - 1);
386 befs_ino->i_data.symlink[BEFS_SYMLINK_LEN - 1] = '\0';
387 } else {
388 int num_blks;
389
390 befs_ino->i_data.ds =
391 fsds_to_cpu(sb, &raw_inode->data.datastream);
392
393 num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
394 inode->i_blocks =
395 num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
396 inode->i_size = befs_ino->i_data.ds.size;
397 }
398
399 inode->i_mapping->a_ops = &befs_aops;
400
401 if (S_ISREG(inode->i_mode)) {
402 inode->i_fop = &generic_ro_fops;
403 } else if (S_ISDIR(inode->i_mode)) {
404 inode->i_op = &befs_dir_inode_operations;
405 inode->i_fop = &befs_dir_operations;
406 } else if (S_ISLNK(inode->i_mode)) {
407 inode->i_op = &befs_symlink_inode_operations;
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, "<--- befs_read_inode()");
417 unlock_new_inode(inode);
418 return inode;
419
420 unacquire_bh:
421 brelse(bh);
422
423 unacquire_none:
424 iget_failed(inode);
425 befs_debug(sb, "<--- befs_read_inode() - Bad inode");
426 return ERR_PTR(ret);
427}
428
429/* Initialize the inode cache. Called at fs setup.
430 *
431 * Taken from NFS implementation by Al Viro.
432 */
433static int
434befs_init_inodecache(void)
435{
436 befs_inode_cachep = kmem_cache_create("befs_inode_cache",
437 sizeof (struct befs_inode_info),
438 0, (SLAB_RECLAIM_ACCOUNT|
439 SLAB_MEM_SPREAD),
440 init_once);
441 if (befs_inode_cachep == NULL) {
442 printk(KERN_ERR "befs_init_inodecache: "
443 "Couldn't initialize inode slabcache\n");
444 return -ENOMEM;
445 }
446
447 return 0;
448}
449
450/* Called at fs teardown.
451 *
452 * Taken from NFS implementation by Al Viro.
453 */
454static void
455befs_destroy_inodecache(void)
456{
457 kmem_cache_destroy(befs_inode_cachep);
458}
459
460/*
461 * The inode of symbolic link is different to data stream.
462 * The data stream become link name. Unless the LONG_SYMLINK
463 * flag is set.
464 */
465static void *
466befs_follow_link(struct dentry *dentry, struct nameidata *nd)
467{
468 befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
469 char *link;
470
471 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
472 struct super_block *sb = dentry->d_sb;
473 befs_data_stream *data = &befs_ino->i_data.ds;
474 befs_off_t len = data->size;
475
476 if (len == 0) {
477 befs_error(sb, "Long symlink with illegal length");
478 link = ERR_PTR(-EIO);
479 } else {
480 befs_debug(sb, "Follow long symlink");
481
482 link = kmalloc(len, GFP_NOFS);
483 if (!link) {
484 link = ERR_PTR(-ENOMEM);
485 } else if (befs_read_lsymlink(sb, data, link, len) != len) {
486 kfree(link);
487 befs_error(sb, "Failed to read entire long symlink");
488 link = ERR_PTR(-EIO);
489 } else {
490 link[len - 1] = '\0';
491 }
492 }
493 } else {
494 link = befs_ino->i_data.symlink;
495 }
496
497 nd_set_link(nd, link);
498 return NULL;
499}
500
501static void befs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
502{
503 befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
504 if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
505 char *link = nd_get_link(nd);
506 if (!IS_ERR(link))
507 kfree(link);
508 }
509}
510
511/*
512 * UTF-8 to NLS charset convert routine
513 *
514 *
515 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
516 * the nls tables directly
517 */
518
519static int
520befs_utf2nls(struct super_block *sb, const char *in,
521 int in_len, char **out, int *out_len)
522{
523 struct nls_table *nls = BEFS_SB(sb)->nls;
524 int i, o;
525 unicode_t uni;
526 int unilen, utflen;
527 char *result;
528 /* The utf8->nls conversion won't make the final nls string bigger
529 * than the utf one, but if the string is pure ascii they'll have the
530 * same width and an extra char is needed to save the additional \0
531 */
532 int maxlen = in_len + 1;
533
534 befs_debug(sb, "---> utf2nls()");
535
536 if (!nls) {
537 befs_error(sb, "befs_utf2nls called with no NLS table loaded");
538 return -EINVAL;
539 }
540
541 *out = result = kmalloc(maxlen, GFP_NOFS);
542 if (!*out) {
543 befs_error(sb, "befs_utf2nls() cannot allocate memory");
544 *out_len = 0;
545 return -ENOMEM;
546 }
547
548 for (i = o = 0; i < in_len; i += utflen, o += unilen) {
549
550 /* convert from UTF-8 to Unicode */
551 utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
552 if (utflen < 0)
553 goto conv_err;
554
555 /* convert from Unicode to nls */
556 if (uni > MAX_WCHAR_T)
557 goto conv_err;
558 unilen = nls->uni2char(uni, &result[o], in_len - o);
559 if (unilen < 0)
560 goto conv_err;
561 }
562 result[o] = '\0';
563 *out_len = o;
564
565 befs_debug(sb, "<--- utf2nls()");
566
567 return o;
568
569 conv_err:
570 befs_error(sb, "Name using character set %s contains a character that "
571 "cannot be converted to unicode.", nls->charset);
572 befs_debug(sb, "<--- utf2nls()");
573 kfree(result);
574 return -EILSEQ;
575}
576
577/**
578 * befs_nls2utf - Convert NLS string to utf8 encodeing
579 * @sb: Superblock
580 * @src: Input string buffer in NLS format
581 * @srclen: Length of input string in bytes
582 * @dest: The output string in UTF-8 format
583 * @destlen: Length of the output buffer
584 *
585 * Converts input string @src, which is in the format of the loaded NLS map,
586 * into a utf8 string.
587 *
588 * The destination string @dest is allocated by this function and the caller is
589 * responsible for freeing it with kfree()
590 *
591 * On return, *@destlen is the length of @dest in bytes.
592 *
593 * On success, the return value is the number of utf8 characters written to
594 * the output buffer @dest.
595 *
596 * On Failure, a negative number coresponding to the error code is returned.
597 */
598
599static int
600befs_nls2utf(struct super_block *sb, const char *in,
601 int in_len, char **out, int *out_len)
602{
603 struct nls_table *nls = BEFS_SB(sb)->nls;
604 int i, o;
605 wchar_t uni;
606 int unilen, utflen;
607 char *result;
608 /* There're nls characters that will translate to 3-chars-wide UTF-8
609 * characters, a additional byte is needed to save the final \0
610 * in special cases */
611 int maxlen = (3 * in_len) + 1;
612
613 befs_debug(sb, "---> nls2utf()\n");
614
615 if (!nls) {
616 befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
617 return -EINVAL;
618 }
619
620 *out = result = kmalloc(maxlen, GFP_NOFS);
621 if (!*out) {
622 befs_error(sb, "befs_nls2utf() cannot allocate memory");
623 *out_len = 0;
624 return -ENOMEM;
625 }
626
627 for (i = o = 0; i < in_len; i += unilen, o += utflen) {
628
629 /* convert from nls to unicode */
630 unilen = nls->char2uni(&in[i], in_len - i, &uni);
631 if (unilen < 0)
632 goto conv_err;
633
634 /* convert from unicode to UTF-8 */
635 utflen = utf32_to_utf8(uni, &result[o], 3);
636 if (utflen <= 0)
637 goto conv_err;
638 }
639
640 result[o] = '\0';
641 *out_len = o;
642
643 befs_debug(sb, "<--- nls2utf()");
644
645 return i;
646
647 conv_err:
648 befs_error(sb, "Name using charecter set %s contains a charecter that "
649 "cannot be converted to unicode.", nls->charset);
650 befs_debug(sb, "<--- nls2utf()");
651 kfree(result);
652 return -EILSEQ;
653}
654
655/**
656 * Use the
657 *
658 */
659enum {
660 Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
661};
662
663static const match_table_t befs_tokens = {
664 {Opt_uid, "uid=%d"},
665 {Opt_gid, "gid=%d"},
666 {Opt_charset, "iocharset=%s"},
667 {Opt_debug, "debug"},
668 {Opt_err, NULL}
669};
670
671static int
672parse_options(char *options, befs_mount_options * opts)
673{
674 char *p;
675 substring_t args[MAX_OPT_ARGS];
676 int option;
677
678 /* Initialize options */
679 opts->uid = 0;
680 opts->gid = 0;
681 opts->use_uid = 0;
682 opts->use_gid = 0;
683 opts->iocharset = NULL;
684 opts->debug = 0;
685
686 if (!options)
687 return 1;
688
689 while ((p = strsep(&options, ",")) != NULL) {
690 int token;
691 if (!*p)
692 continue;
693
694 token = match_token(p, befs_tokens, args);
695 switch (token) {
696 case Opt_uid:
697 if (match_int(&args[0], &option))
698 return 0;
699 if (option < 0) {
700 printk(KERN_ERR "BeFS: Invalid uid %d, "
701 "using default\n", option);
702 break;
703 }
704 opts->uid = option;
705 opts->use_uid = 1;
706 break;
707 case Opt_gid:
708 if (match_int(&args[0], &option))
709 return 0;
710 if (option < 0) {
711 printk(KERN_ERR "BeFS: Invalid gid %d, "
712 "using default\n", option);
713 break;
714 }
715 opts->gid = option;
716 opts->use_gid = 1;
717 break;
718 case Opt_charset:
719 kfree(opts->iocharset);
720 opts->iocharset = match_strdup(&args[0]);
721 if (!opts->iocharset) {
722 printk(KERN_ERR "BeFS: allocation failure for "
723 "iocharset string\n");
724 return 0;
725 }
726 break;
727 case Opt_debug:
728 opts->debug = 1;
729 break;
730 default:
731 printk(KERN_ERR "BeFS: Unrecognized mount option \"%s\" "
732 "or missing value\n", p);
733 return 0;
734 }
735 }
736 return 1;
737}
738
739/* This function has the responsibiltiy of getting the
740 * filesystem ready for unmounting.
741 * Basically, we free everything that we allocated in
742 * befs_read_inode
743 */
744static void
745befs_put_super(struct super_block *sb)
746{
747 kfree(BEFS_SB(sb)->mount_opts.iocharset);
748 BEFS_SB(sb)->mount_opts.iocharset = NULL;
749 unload_nls(BEFS_SB(sb)->nls);
750 kfree(sb->s_fs_info);
751 sb->s_fs_info = NULL;
752}
753
754/* Allocate private field of the superblock, fill it.
755 *
756 * Finish filling the public superblock fields
757 * Make the root directory
758 * Load a set of NLS translations if needed.
759 */
760static int
761befs_fill_super(struct super_block *sb, void *data, int silent)
762{
763 struct buffer_head *bh;
764 befs_sb_info *befs_sb;
765 befs_super_block *disk_sb;
766 struct inode *root;
767 long ret = -EINVAL;
768 const unsigned long sb_block = 0;
769 const off_t x86_sb_off = 512;
770
771 save_mount_options(sb, data);
772
773 sb->s_fs_info = kmalloc(sizeof (*befs_sb), GFP_KERNEL);
774 if (sb->s_fs_info == NULL) {
775 printk(KERN_ERR
776 "BeFS(%s): Unable to allocate memory for private "
777 "portion of superblock. Bailing.\n", sb->s_id);
778 goto unacquire_none;
779 }
780 befs_sb = BEFS_SB(sb);
781 memset(befs_sb, 0, sizeof(befs_sb_info));
782
783 if (!parse_options((char *) data, &befs_sb->mount_opts)) {
784 befs_error(sb, "cannot parse mount options");
785 goto unacquire_priv_sbp;
786 }
787
788 befs_debug(sb, "---> befs_fill_super()");
789
790#ifndef CONFIG_BEFS_RW
791 if (!(sb->s_flags & MS_RDONLY)) {
792 befs_warning(sb,
793 "No write support. Marking filesystem read-only");
794 sb->s_flags |= MS_RDONLY;
795 }
796#endif /* CONFIG_BEFS_RW */
797
798 /*
799 * Set dummy blocksize to read super block.
800 * Will be set to real fs blocksize later.
801 *
802 * Linux 2.4.10 and later refuse to read blocks smaller than
803 * the hardsect size for the device. But we also need to read at
804 * least 1k to get the second 512 bytes of the volume.
805 * -WD 10-26-01
806 */
807 sb_min_blocksize(sb, 1024);
808
809 if (!(bh = sb_bread(sb, sb_block))) {
810 befs_error(sb, "unable to read superblock");
811 goto unacquire_priv_sbp;
812 }
813
814 /* account for offset of super block on x86 */
815 disk_sb = (befs_super_block *) bh->b_data;
816 if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
817 (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
818 befs_debug(sb, "Using PPC superblock location");
819 } else {
820 befs_debug(sb, "Using x86 superblock location");
821 disk_sb =
822 (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
823 }
824
825 if (befs_load_sb(sb, disk_sb) != BEFS_OK)
826 goto unacquire_bh;
827
828 befs_dump_super_block(sb, disk_sb);
829
830 brelse(bh);
831
832 if (befs_check_sb(sb) != BEFS_OK)
833 goto unacquire_priv_sbp;
834
835 if( befs_sb->num_blocks > ~((sector_t)0) ) {
836 befs_error(sb, "blocks count: %Lu "
837 "is larger than the host can use",
838 befs_sb->num_blocks);
839 goto unacquire_priv_sbp;
840 }
841
842 /*
843 * set up enough so that it can read an inode
844 * Fill in kernel superblock fields from private sb
845 */
846 sb->s_magic = BEFS_SUPER_MAGIC;
847 /* Set real blocksize of fs */
848 sb_set_blocksize(sb, (ulong) befs_sb->block_size);
849 sb->s_op = &befs_sops;
850 root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
851 if (IS_ERR(root)) {
852 ret = PTR_ERR(root);
853 goto unacquire_priv_sbp;
854 }
855 sb->s_root = d_make_root(root);
856 if (!sb->s_root) {
857 befs_error(sb, "get root inode failed");
858 goto unacquire_priv_sbp;
859 }
860
861 /* load nls library */
862 if (befs_sb->mount_opts.iocharset) {
863 befs_debug(sb, "Loading nls: %s",
864 befs_sb->mount_opts.iocharset);
865 befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
866 if (!befs_sb->nls) {
867 befs_warning(sb, "Cannot load nls %s"
868 " loading default nls",
869 befs_sb->mount_opts.iocharset);
870 befs_sb->nls = load_nls_default();
871 }
872 /* load default nls if none is specified in mount options */
873 } else {
874 befs_debug(sb, "Loading default nls");
875 befs_sb->nls = load_nls_default();
876 }
877
878 return 0;
879/*****************/
880 unacquire_bh:
881 brelse(bh);
882
883 unacquire_priv_sbp:
884 kfree(befs_sb->mount_opts.iocharset);
885 kfree(sb->s_fs_info);
886
887 unacquire_none:
888 sb->s_fs_info = NULL;
889 return ret;
890}
891
892static int
893befs_remount(struct super_block *sb, int *flags, char *data)
894{
895 if (!(*flags & MS_RDONLY))
896 return -EINVAL;
897 return 0;
898}
899
900static int
901befs_statfs(struct dentry *dentry, struct kstatfs *buf)
902{
903 struct super_block *sb = dentry->d_sb;
904 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
905
906 befs_debug(sb, "---> befs_statfs()");
907
908 buf->f_type = BEFS_SUPER_MAGIC;
909 buf->f_bsize = sb->s_blocksize;
910 buf->f_blocks = BEFS_SB(sb)->num_blocks;
911 buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
912 buf->f_bavail = buf->f_bfree;
913 buf->f_files = 0; /* UNKNOWN */
914 buf->f_ffree = 0; /* UNKNOWN */
915 buf->f_fsid.val[0] = (u32)id;
916 buf->f_fsid.val[1] = (u32)(id >> 32);
917 buf->f_namelen = BEFS_NAME_LEN;
918
919 befs_debug(sb, "<--- befs_statfs()");
920
921 return 0;
922}
923
924static struct dentry *
925befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
926 void *data)
927{
928 return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
929}
930
931static struct file_system_type befs_fs_type = {
932 .owner = THIS_MODULE,
933 .name = "befs",
934 .mount = befs_mount,
935 .kill_sb = kill_block_super,
936 .fs_flags = FS_REQUIRES_DEV,
937};
938
939static int __init
940init_befs_fs(void)
941{
942 int err;
943
944 printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
945
946 err = befs_init_inodecache();
947 if (err)
948 goto unacquire_none;
949
950 err = register_filesystem(&befs_fs_type);
951 if (err)
952 goto unacquire_inodecache;
953
954 return 0;
955
956unacquire_inodecache:
957 befs_destroy_inodecache();
958
959unacquire_none:
960 return err;
961}
962
963static void __exit
964exit_befs_fs(void)
965{
966 befs_destroy_inodecache();
967
968 unregister_filesystem(&befs_fs_type);
969}
970
971/*
972Macros that typecheck the init and exit functions,
973ensures that they are called at init and cleanup,
974and eliminates warnings about unused functions.
975*/
976module_init(init_befs_fs)
977module_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)