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v3.5.6
  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)
v4.6
  1/*
  2 * linux/fs/befs/linuxvfs.c
  3 *
  4 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
  5 *
  6 */
  7
  8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  9
 10#include <linux/module.h>
 11#include <linux/slab.h>
 12#include <linux/fs.h>
 13#include <linux/errno.h>
 14#include <linux/stat.h>
 15#include <linux/nls.h>
 16#include <linux/buffer_head.h>
 17#include <linux/vfs.h>
 18#include <linux/parser.h>
 19#include <linux/namei.h>
 20#include <linux/sched.h>
 21
 22#include "befs.h"
 23#include "btree.h"
 24#include "inode.h"
 25#include "datastream.h"
 26#include "super.h"
 27#include "io.h"
 28
 29MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
 30MODULE_AUTHOR("Will Dyson");
 31MODULE_LICENSE("GPL");
 32
 33/* The units the vfs expects inode->i_blocks to be in */
 34#define VFS_BLOCK_SIZE 512
 35
 36static int befs_readdir(struct file *, struct dir_context *);
 37static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
 38static int befs_readpage(struct file *file, struct page *page);
 39static sector_t befs_bmap(struct address_space *mapping, sector_t block);
 40static struct dentry *befs_lookup(struct inode *, struct dentry *, unsigned int);
 41static struct inode *befs_iget(struct super_block *, unsigned long);
 42static struct inode *befs_alloc_inode(struct super_block *sb);
 43static void befs_destroy_inode(struct inode *inode);
 
 44static void befs_destroy_inodecache(void);
 45static int befs_symlink_readpage(struct file *, struct page *);
 
 46static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
 47			char **out, int *out_len);
 48static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
 49			char **out, int *out_len);
 50static void befs_put_super(struct super_block *);
 51static int befs_remount(struct super_block *, int *, char *);
 52static int befs_statfs(struct dentry *, struct kstatfs *);
 53static int parse_options(char *, struct befs_mount_options *);
 54
 55static const struct super_operations befs_sops = {
 56	.alloc_inode	= befs_alloc_inode,	/* allocate a new inode */
 57	.destroy_inode	= befs_destroy_inode, /* deallocate an inode */
 58	.put_super	= befs_put_super,	/* uninit super */
 59	.statfs		= befs_statfs,	/* statfs */
 60	.remount_fs	= befs_remount,
 61	.show_options	= generic_show_options,
 62};
 63
 64/* slab cache for befs_inode_info objects */
 65static struct kmem_cache *befs_inode_cachep;
 66
 67static const struct file_operations befs_dir_operations = {
 68	.read		= generic_read_dir,
 69	.iterate	= befs_readdir,
 70	.llseek		= generic_file_llseek,
 71};
 72
 73static const struct inode_operations befs_dir_inode_operations = {
 74	.lookup		= befs_lookup,
 75};
 76
 77static const struct address_space_operations befs_aops = {
 78	.readpage	= befs_readpage,
 79	.bmap		= befs_bmap,
 80};
 81
 82static const struct address_space_operations befs_symlink_aops = {
 83	.readpage	= befs_symlink_readpage,
 
 
 84};
 85
 86/* 
 87 * Called by generic_file_read() to read a page of data
 88 * 
 89 * In turn, simply calls a generic block read function and
 90 * passes it the address of befs_get_block, for mapping file
 91 * positions to disk blocks.
 92 */
 93static int
 94befs_readpage(struct file *file, struct page *page)
 95{
 96	return block_read_full_page(page, befs_get_block);
 97}
 98
 99static sector_t
100befs_bmap(struct address_space *mapping, sector_t block)
101{
102	return generic_block_bmap(mapping, block, befs_get_block);
103}
104
105/* 
106 * Generic function to map a file position (block) to a 
107 * disk offset (passed back in bh_result).
108 *
109 * Used by many higher level functions.
110 *
111 * Calls befs_fblock2brun() in datastream.c to do the real work.
112 *
113 * -WD 10-26-01
114 */
115
116static int
117befs_get_block(struct inode *inode, sector_t block,
118	       struct buffer_head *bh_result, int create)
119{
120	struct super_block *sb = inode->i_sb;
121	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
122	befs_block_run run = BAD_IADDR;
123	int res = 0;
124	ulong disk_off;
125
126	befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
127		   (unsigned long)inode->i_ino, (long)block);
 
 
 
 
 
 
 
 
128	if (create) {
129		befs_error(sb, "befs_get_block() was asked to write to "
130			   "block %ld in inode %lu", (long)block,
131			   (unsigned long)inode->i_ino);
132		return -EPERM;
133	}
134
135	res = befs_fblock2brun(sb, ds, block, &run);
136	if (res != BEFS_OK) {
137		befs_error(sb,
138			   "<--- %s for inode %lu, block %ld ERROR",
139			   __func__, (unsigned long)inode->i_ino,
140			   (long)block);
141		return -EFBIG;
142	}
143
144	disk_off = (ulong) iaddr2blockno(sb, &run);
145
146	map_bh(bh_result, inode->i_sb, disk_off);
147
148	befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu",
149		  __func__, (unsigned long)inode->i_ino, (long)block,
150		  (unsigned long)disk_off);
151
152	return 0;
153}
154
155static struct dentry *
156befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
157{
158	struct inode *inode = NULL;
159	struct super_block *sb = dir->i_sb;
160	befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
161	befs_off_t offset;
162	int ret;
163	int utfnamelen;
164	char *utfname;
165	const char *name = dentry->d_name.name;
166
167	befs_debug(sb, "---> %s name %pd inode %ld", __func__,
168		   dentry, dir->i_ino);
169
170	/* Convert to UTF-8 */
171	if (BEFS_SB(sb)->nls) {
172		ret =
173		    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
174		if (ret < 0) {
175			befs_debug(sb, "<--- %s ERROR", __func__);
176			return ERR_PTR(ret);
177		}
178		ret = befs_btree_find(sb, ds, utfname, &offset);
179		kfree(utfname);
180
181	} else {
182		ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
183	}
184
185	if (ret == BEFS_BT_NOT_FOUND) {
186		befs_debug(sb, "<--- %s %pd not found", __func__, dentry);
 
187		return ERR_PTR(-ENOENT);
188
189	} else if (ret != BEFS_OK || offset == 0) {
190		befs_warning(sb, "<--- %s Error", __func__);
191		return ERR_PTR(-ENODATA);
192	}
193
194	inode = befs_iget(dir->i_sb, (ino_t) offset);
195	if (IS_ERR(inode))
196		return ERR_CAST(inode);
197
198	d_add(dentry, inode);
199
200	befs_debug(sb, "<--- %s", __func__);
201
202	return NULL;
203}
204
205static int
206befs_readdir(struct file *file, struct dir_context *ctx)
207{
208	struct inode *inode = file_inode(file);
209	struct super_block *sb = inode->i_sb;
210	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
211	befs_off_t value;
212	int result;
213	size_t keysize;
214	unsigned char d_type;
215	char keybuf[BEFS_NAME_LEN + 1];
 
 
 
 
 
 
 
216
217	befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld",
218		  __func__, file, inode->i_ino, ctx->pos);
219
220more:
221	result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,
222				 keybuf, &keysize, &value);
223
224	if (result == BEFS_ERR) {
225		befs_debug(sb, "<--- %s ERROR", __func__);
226		befs_error(sb, "IO error reading %pD (inode %lu)",
227			   file, inode->i_ino);
228		return -EIO;
229
230	} else if (result == BEFS_BT_END) {
231		befs_debug(sb, "<--- %s END", __func__);
232		return 0;
233
234	} else if (result == BEFS_BT_EMPTY) {
235		befs_debug(sb, "<--- %s Empty directory", __func__);
236		return 0;
237	}
238
239	d_type = DT_UNKNOWN;
240
241	/* Convert to NLS */
242	if (BEFS_SB(sb)->nls) {
243		char *nlsname;
244		int nlsnamelen;
245		result =
246		    befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
247		if (result < 0) {
248			befs_debug(sb, "<--- %s ERROR", __func__);
249			return result;
250		}
251		if (!dir_emit(ctx, nlsname, nlsnamelen,
252				 (ino_t) value, d_type)) {
253			kfree(nlsname);
254			return 0;
255		}
256		kfree(nlsname);
 
257	} else {
258		if (!dir_emit(ctx, keybuf, keysize,
259				 (ino_t) value, d_type))
260			return 0;
261	}
262	ctx->pos++;
263	goto more;
 
 
 
 
264}
265
266static struct inode *
267befs_alloc_inode(struct super_block *sb)
268{
269	struct befs_inode_info *bi;
270
271	bi = kmem_cache_alloc(befs_inode_cachep, GFP_KERNEL);
272        if (!bi)
273                return NULL;
274        return &bi->vfs_inode;
275}
276
277static void befs_i_callback(struct rcu_head *head)
278{
279	struct inode *inode = container_of(head, struct inode, i_rcu);
280        kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
281}
282
283static void befs_destroy_inode(struct inode *inode)
284{
285	call_rcu(&inode->i_rcu, befs_i_callback);
286}
287
288static void init_once(void *foo)
289{
290        struct befs_inode_info *bi = (struct befs_inode_info *) foo;
291
292	inode_init_once(&bi->vfs_inode);
293}
294
295static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
296{
297	struct buffer_head *bh = NULL;
298	befs_inode *raw_inode = NULL;
299	struct befs_sb_info *befs_sb = BEFS_SB(sb);
300	struct befs_inode_info *befs_ino = NULL;
 
301	struct inode *inode;
302	long ret = -EIO;
303
304	befs_debug(sb, "---> %s inode = %lu", __func__, ino);
305
306	inode = iget_locked(sb, ino);
307	if (!inode)
308		return ERR_PTR(-ENOMEM);
309	if (!(inode->i_state & I_NEW))
310		return inode;
311
312	befs_ino = BEFS_I(inode);
313
314	/* convert from vfs's inode number to befs's inode number */
315	befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
316
317	befs_debug(sb, "  real inode number [%u, %hu, %hu]",
318		   befs_ino->i_inode_num.allocation_group,
319		   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
320
321	bh = befs_bread(sb, inode->i_ino);
322	if (!bh) {
323		befs_error(sb, "unable to read inode block - "
324			   "inode = %lu", inode->i_ino);
325		goto unacquire_none;
326	}
327
328	raw_inode = (befs_inode *) bh->b_data;
329
330	befs_dump_inode(sb, raw_inode);
331
332	if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
333		befs_error(sb, "Bad inode: %lu", inode->i_ino);
334		goto unacquire_bh;
335	}
336
337	inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
338
339	/*
340	 * set uid and gid.  But since current BeOS is single user OS, so
341	 * you can change by "uid" or "gid" options.
342	 */   
343
344	inode->i_uid = befs_sb->mount_opts.use_uid ?
345		befs_sb->mount_opts.uid :
346		make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
347	inode->i_gid = befs_sb->mount_opts.use_gid ?
348		befs_sb->mount_opts.gid :
349		make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
350
351	set_nlink(inode, 1);
352
353	/*
354	 * BEFS's time is 64 bits, but current VFS is 32 bits...
355	 * BEFS don't have access time. Nor inode change time. VFS
356	 * doesn't have creation time.
357	 * Also, the lower 16 bits of the last_modified_time and 
358	 * create_time are just a counter to help ensure uniqueness
359	 * for indexing purposes. (PFD, page 54)
360	 */
361
362	inode->i_mtime.tv_sec =
363	    fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
364	inode->i_mtime.tv_nsec = 0;   /* lower 16 bits are not a time */	
365	inode->i_ctime = inode->i_mtime;
366	inode->i_atime = inode->i_mtime;
367
368	befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
369	befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
370	befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
371	befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
372
373	if (S_ISLNK(inode->i_mode) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
374		inode->i_size = 0;
375		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
376		strlcpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
377			BEFS_SYMLINK_LEN);
 
378	} else {
379		int num_blks;
380
381		befs_ino->i_data.ds =
382		    fsds_to_cpu(sb, &raw_inode->data.datastream);
383
384		num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
385		inode->i_blocks =
386		    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
387		inode->i_size = befs_ino->i_data.ds.size;
388	}
389
390	inode->i_mapping->a_ops = &befs_aops;
391
392	if (S_ISREG(inode->i_mode)) {
393		inode->i_fop = &generic_ro_fops;
394	} else if (S_ISDIR(inode->i_mode)) {
395		inode->i_op = &befs_dir_inode_operations;
396		inode->i_fop = &befs_dir_operations;
397	} else if (S_ISLNK(inode->i_mode)) {
398		if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
399			inode->i_op = &page_symlink_inode_operations;
400			inode_nohighmem(inode);
401			inode->i_mapping->a_ops = &befs_symlink_aops;
402		} else {
403			inode->i_link = befs_ino->i_data.symlink;
404			inode->i_op = &simple_symlink_inode_operations;
405		}
406	} else {
407		befs_error(sb, "Inode %lu is not a regular file, "
408			   "directory or symlink. THAT IS WRONG! BeFS has no "
409			   "on disk special files", inode->i_ino);
410		goto unacquire_bh;
411	}
412
413	brelse(bh);
414	befs_debug(sb, "<--- %s", __func__);
415	unlock_new_inode(inode);
416	return inode;
417
418      unacquire_bh:
419	brelse(bh);
420
421      unacquire_none:
422	iget_failed(inode);
423	befs_debug(sb, "<--- %s - Bad inode", __func__);
424	return ERR_PTR(ret);
425}
426
427/* Initialize the inode cache. Called at fs setup.
428 *
429 * Taken from NFS implementation by Al Viro.
430 */
431static int __init
432befs_init_inodecache(void)
433{
434	befs_inode_cachep = kmem_cache_create("befs_inode_cache",
435					      sizeof (struct befs_inode_info),
436					      0, (SLAB_RECLAIM_ACCOUNT|
437						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
438					      init_once);
439	if (befs_inode_cachep == NULL) {
440		pr_err("%s: Couldn't initialize inode slabcache\n", __func__);
 
441		return -ENOMEM;
442	}
 
443	return 0;
444}
445
446/* Called at fs teardown.
447 * 
448 * Taken from NFS implementation by Al Viro.
449 */
450static void
451befs_destroy_inodecache(void)
452{
453	/*
454	 * Make sure all delayed rcu free inodes are flushed before we
455	 * destroy cache.
456	 */
457	rcu_barrier();
458	kmem_cache_destroy(befs_inode_cachep);
459}
460
461/*
462 * The inode of symbolic link is different to data stream.
463 * The data stream become link name. Unless the LONG_SYMLINK
464 * flag is set.
465 */
466static int befs_symlink_readpage(struct file *unused, struct page *page)
 
467{
468	struct inode *inode = page->mapping->host;
469	struct super_block *sb = inode->i_sb;
470	struct befs_inode_info *befs_ino = BEFS_I(inode);
471	befs_data_stream *data = &befs_ino->i_data.ds;
472	befs_off_t len = data->size;
473	char *link = page_address(page);
474
475	if (len == 0 || len > PAGE_SIZE) {
476		befs_error(sb, "Long symlink with illegal length");
477		goto fail;
478	}
479	befs_debug(sb, "Follow long symlink");
480
481	if (befs_read_lsymlink(sb, data, link, len) != len) {
482		befs_error(sb, "Failed to read entire long symlink");
483		goto fail;
484	}
485	link[len - 1] = '\0';
486	SetPageUptodate(page);
487	unlock_page(page);
488	return 0;
489fail:
490	SetPageError(page);
491	unlock_page(page);
492	return -EIO;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
493}
494
495/*
496 * UTF-8 to NLS charset  convert routine
497 * 
498 *
499 * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
500 * the nls tables directly
501 */
502
503static int
504befs_utf2nls(struct super_block *sb, const char *in,
505	     int in_len, char **out, int *out_len)
506{
507	struct nls_table *nls = BEFS_SB(sb)->nls;
508	int i, o;
509	unicode_t uni;
510	int unilen, utflen;
511	char *result;
512	/* The utf8->nls conversion won't make the final nls string bigger
513	 * than the utf one, but if the string is pure ascii they'll have the
514	 * same width and an extra char is needed to save the additional \0
515	 */
516	int maxlen = in_len + 1;
517
518	befs_debug(sb, "---> %s", __func__);
519
520	if (!nls) {
521		befs_error(sb, "%s called with no NLS table loaded", __func__);
522		return -EINVAL;
523	}
524
525	*out = result = kmalloc(maxlen, GFP_NOFS);
526	if (!*out) {
527		befs_error(sb, "%s cannot allocate memory", __func__);
528		*out_len = 0;
529		return -ENOMEM;
530	}
531
532	for (i = o = 0; i < in_len; i += utflen, o += unilen) {
533
534		/* convert from UTF-8 to Unicode */
535		utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
536		if (utflen < 0)
537			goto conv_err;
538
539		/* convert from Unicode to nls */
540		if (uni > MAX_WCHAR_T)
541			goto conv_err;
542		unilen = nls->uni2char(uni, &result[o], in_len - o);
543		if (unilen < 0)
544			goto conv_err;
545	}
546	result[o] = '\0';
547	*out_len = o;
548
549	befs_debug(sb, "<--- %s", __func__);
550
551	return o;
552
553      conv_err:
554	befs_error(sb, "Name using character set %s contains a character that "
555		   "cannot be converted to unicode.", nls->charset);
556	befs_debug(sb, "<--- %s", __func__);
557	kfree(result);
558	return -EILSEQ;
559}
560
561/**
562 * befs_nls2utf - Convert NLS string to utf8 encodeing
563 * @sb: Superblock
564 * @in: Input string buffer in NLS format
565 * @in_len: Length of input string in bytes
566 * @out: The output string in UTF-8 format
567 * @out_len: Length of the output buffer
568 * 
569 * Converts input string @in, which is in the format of the loaded NLS map,
570 * into a utf8 string.
571 * 
572 * The destination string @out is allocated by this function and the caller is
573 * responsible for freeing it with kfree()
574 * 
575 * On return, *@out_len is the length of @out in bytes.
576 *
577 * On success, the return value is the number of utf8 characters written to
578 * the output buffer @out.
579 *  
580 * On Failure, a negative number coresponding to the error code is returned.
581 */
582
583static int
584befs_nls2utf(struct super_block *sb, const char *in,
585	     int in_len, char **out, int *out_len)
586{
587	struct nls_table *nls = BEFS_SB(sb)->nls;
588	int i, o;
589	wchar_t uni;
590	int unilen, utflen;
591	char *result;
592	/* There're nls characters that will translate to 3-chars-wide UTF-8
593	 * characters, a additional byte is needed to save the final \0
594	 * in special cases */
595	int maxlen = (3 * in_len) + 1;
596
597	befs_debug(sb, "---> %s\n", __func__);
598
599	if (!nls) {
600		befs_error(sb, "%s called with no NLS table loaded.",
601			   __func__);
602		return -EINVAL;
603	}
604
605	*out = result = kmalloc(maxlen, GFP_NOFS);
606	if (!*out) {
607		befs_error(sb, "%s cannot allocate memory", __func__);
608		*out_len = 0;
609		return -ENOMEM;
610	}
611
612	for (i = o = 0; i < in_len; i += unilen, o += utflen) {
613
614		/* convert from nls to unicode */
615		unilen = nls->char2uni(&in[i], in_len - i, &uni);
616		if (unilen < 0)
617			goto conv_err;
618
619		/* convert from unicode to UTF-8 */
620		utflen = utf32_to_utf8(uni, &result[o], 3);
621		if (utflen <= 0)
622			goto conv_err;
623	}
624
625	result[o] = '\0';
626	*out_len = o;
627
628	befs_debug(sb, "<--- %s", __func__);
629
630	return i;
631
632      conv_err:
633	befs_error(sb, "Name using charecter set %s contains a charecter that "
634		   "cannot be converted to unicode.", nls->charset);
635	befs_debug(sb, "<--- %s", __func__);
636	kfree(result);
637	return -EILSEQ;
638}
639
640/**
641 * Use the
642 *
643 */
644enum {
645	Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
646};
647
648static const match_table_t befs_tokens = {
649	{Opt_uid, "uid=%d"},
650	{Opt_gid, "gid=%d"},
651	{Opt_charset, "iocharset=%s"},
652	{Opt_debug, "debug"},
653	{Opt_err, NULL}
654};
655
656static int
657parse_options(char *options, struct befs_mount_options *opts)
658{
659	char *p;
660	substring_t args[MAX_OPT_ARGS];
661	int option;
662	kuid_t uid;
663	kgid_t gid;
664
665	/* Initialize options */
666	opts->uid = GLOBAL_ROOT_UID;
667	opts->gid = GLOBAL_ROOT_GID;
668	opts->use_uid = 0;
669	opts->use_gid = 0;
670	opts->iocharset = NULL;
671	opts->debug = 0;
672
673	if (!options)
674		return 1;
675
676	while ((p = strsep(&options, ",")) != NULL) {
677		int token;
678		if (!*p)
679			continue;
680
681		token = match_token(p, befs_tokens, args);
682		switch (token) {
683		case Opt_uid:
684			if (match_int(&args[0], &option))
685				return 0;
686			uid = INVALID_UID;
687			if (option >= 0)
688				uid = make_kuid(current_user_ns(), option);
689			if (!uid_valid(uid)) {
690				pr_err("Invalid uid %d, "
691				       "using default\n", option);
692				break;
693			}
694			opts->uid = uid;
695			opts->use_uid = 1;
696			break;
697		case Opt_gid:
698			if (match_int(&args[0], &option))
699				return 0;
700			gid = INVALID_GID;
701			if (option >= 0)
702				gid = make_kgid(current_user_ns(), option);
703			if (!gid_valid(gid)) {
704				pr_err("Invalid gid %d, "
705				       "using default\n", option);
706				break;
707			}
708			opts->gid = gid;
709			opts->use_gid = 1;
710			break;
711		case Opt_charset:
712			kfree(opts->iocharset);
713			opts->iocharset = match_strdup(&args[0]);
714			if (!opts->iocharset) {
715				pr_err("allocation failure for "
716				       "iocharset string\n");
717				return 0;
718			}
719			break;
720		case Opt_debug:
721			opts->debug = 1;
722			break;
723		default:
724			pr_err("Unrecognized mount option \"%s\" "
725			       "or missing value\n", p);
726			return 0;
727		}
728	}
729	return 1;
730}
731
732/* This function has the responsibiltiy of getting the
733 * filesystem ready for unmounting. 
734 * Basically, we free everything that we allocated in
735 * befs_read_inode
736 */
737static void
738befs_put_super(struct super_block *sb)
739{
740	kfree(BEFS_SB(sb)->mount_opts.iocharset);
741	BEFS_SB(sb)->mount_opts.iocharset = NULL;
742	unload_nls(BEFS_SB(sb)->nls);
743	kfree(sb->s_fs_info);
744	sb->s_fs_info = NULL;
745}
746
747/* Allocate private field of the superblock, fill it.
748 *
749 * Finish filling the public superblock fields
750 * Make the root directory
751 * Load a set of NLS translations if needed.
752 */
753static int
754befs_fill_super(struct super_block *sb, void *data, int silent)
755{
756	struct buffer_head *bh;
757	struct befs_sb_info *befs_sb;
758	befs_super_block *disk_sb;
759	struct inode *root;
760	long ret = -EINVAL;
761	const unsigned long sb_block = 0;
762	const off_t x86_sb_off = 512;
763
764	save_mount_options(sb, data);
765
766	sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);
767	if (sb->s_fs_info == NULL) {
768		pr_err("(%s): Unable to allocate memory for private "
 
769		       "portion of superblock. Bailing.\n", sb->s_id);
770		goto unacquire_none;
771	}
772	befs_sb = BEFS_SB(sb);
 
773
774	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
775		befs_error(sb, "cannot parse mount options");
776		goto unacquire_priv_sbp;
777	}
778
779	befs_debug(sb, "---> %s", __func__);
780
 
781	if (!(sb->s_flags & MS_RDONLY)) {
782		befs_warning(sb,
783			     "No write support. Marking filesystem read-only");
784		sb->s_flags |= MS_RDONLY;
785	}
 
786
787	/*
788	 * Set dummy blocksize to read super block.
789	 * Will be set to real fs blocksize later.
790	 *
791	 * Linux 2.4.10 and later refuse to read blocks smaller than
792	 * the hardsect size for the device. But we also need to read at 
793	 * least 1k to get the second 512 bytes of the volume.
794	 * -WD 10-26-01
795	 */ 
796	sb_min_blocksize(sb, 1024);
797
798	if (!(bh = sb_bread(sb, sb_block))) {
799		befs_error(sb, "unable to read superblock");
800		goto unacquire_priv_sbp;
801	}
802
803	/* account for offset of super block on x86 */
804	disk_sb = (befs_super_block *) bh->b_data;
805	if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
806	    (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
807		befs_debug(sb, "Using PPC superblock location");
808	} else {
809		befs_debug(sb, "Using x86 superblock location");
810		disk_sb =
811		    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
812	}
813
814	if ((befs_load_sb(sb, disk_sb) != BEFS_OK) ||
815	    (befs_check_sb(sb) != BEFS_OK))
816		goto unacquire_bh;
817
818	befs_dump_super_block(sb, disk_sb);
819
820	brelse(bh);
821
 
 
 
822	if( befs_sb->num_blocks > ~((sector_t)0) ) {
823		befs_error(sb, "blocks count: %llu "
824			"is larger than the host can use",
825			befs_sb->num_blocks);
826		goto unacquire_priv_sbp;
827	}
828
829	/*
830	 * set up enough so that it can read an inode
831	 * Fill in kernel superblock fields from private sb
832	 */
833	sb->s_magic = BEFS_SUPER_MAGIC;
834	/* Set real blocksize of fs */
835	sb_set_blocksize(sb, (ulong) befs_sb->block_size);
836	sb->s_op = &befs_sops;
837	root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
838	if (IS_ERR(root)) {
839		ret = PTR_ERR(root);
840		goto unacquire_priv_sbp;
841	}
842	sb->s_root = d_make_root(root);
843	if (!sb->s_root) {
844		befs_error(sb, "get root inode failed");
845		goto unacquire_priv_sbp;
846	}
847
848	/* load nls library */
849	if (befs_sb->mount_opts.iocharset) {
850		befs_debug(sb, "Loading nls: %s",
851			   befs_sb->mount_opts.iocharset);
852		befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
853		if (!befs_sb->nls) {
854			befs_warning(sb, "Cannot load nls %s"
855					" loading default nls",
856					befs_sb->mount_opts.iocharset);
857			befs_sb->nls = load_nls_default();
858		}
859	/* load default nls if none is specified  in mount options */
860	} else {
861		befs_debug(sb, "Loading default nls");
862		befs_sb->nls = load_nls_default();
863	}
864
865	return 0;
866/*****************/
867      unacquire_bh:
868	brelse(bh);
869
870      unacquire_priv_sbp:
871	kfree(befs_sb->mount_opts.iocharset);
872	kfree(sb->s_fs_info);
873
874      unacquire_none:
875	sb->s_fs_info = NULL;
876	return ret;
877}
878
879static int
880befs_remount(struct super_block *sb, int *flags, char *data)
881{
882	sync_filesystem(sb);
883	if (!(*flags & MS_RDONLY))
884		return -EINVAL;
885	return 0;
886}
887
888static int
889befs_statfs(struct dentry *dentry, struct kstatfs *buf)
890{
891	struct super_block *sb = dentry->d_sb;
892	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
893
894	befs_debug(sb, "---> %s", __func__);
895
896	buf->f_type = BEFS_SUPER_MAGIC;
897	buf->f_bsize = sb->s_blocksize;
898	buf->f_blocks = BEFS_SB(sb)->num_blocks;
899	buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
900	buf->f_bavail = buf->f_bfree;
901	buf->f_files = 0;	/* UNKNOWN */
902	buf->f_ffree = 0;	/* UNKNOWN */
903	buf->f_fsid.val[0] = (u32)id;
904	buf->f_fsid.val[1] = (u32)(id >> 32);
905	buf->f_namelen = BEFS_NAME_LEN;
906
907	befs_debug(sb, "<--- %s", __func__);
908
909	return 0;
910}
911
912static struct dentry *
913befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
914	    void *data)
915{
916	return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
917}
918
919static struct file_system_type befs_fs_type = {
920	.owner		= THIS_MODULE,
921	.name		= "befs",
922	.mount		= befs_mount,
923	.kill_sb	= kill_block_super,
924	.fs_flags	= FS_REQUIRES_DEV,	
925};
926MODULE_ALIAS_FS("befs");
927
928static int __init
929init_befs_fs(void)
930{
931	int err;
932
933	pr_info("version: %s\n", BEFS_VERSION);
934
935	err = befs_init_inodecache();
936	if (err)
937		goto unacquire_none;
938
939	err = register_filesystem(&befs_fs_type);
940	if (err)
941		goto unacquire_inodecache;
942
943	return 0;
944
945unacquire_inodecache:
946	befs_destroy_inodecache();
947
948unacquire_none:
949	return err;
950}
951
952static void __exit
953exit_befs_fs(void)
954{
955	befs_destroy_inodecache();
956
957	unregister_filesystem(&befs_fs_type);
958}
959
960/*
961Macros that typecheck the init and exit functions,
962ensures that they are called at init and cleanup,
963and eliminates warnings about unused functions.
964*/
965module_init(init_befs_fs)
966module_exit(exit_befs_fs)