patch-2.4.20 linux-2.4.20/fs/befs/linuxvfs.c

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diff -urN linux-2.4.19/fs/befs/linuxvfs.c linux-2.4.20/fs/befs/linuxvfs.c
@@ -0,0 +1,956 @@
+/*
+ * linux/fs/befs/linuxvfs.c
+ *
+ * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
+ *
+ */
+
+#include <linux/blkdev.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/nls.h>
+
+#include "befs_fs.h"
+#include "endian.h"
+
+EXPORT_NO_SYMBOLS;
+MODULE_DESCRIPTION("BeOS File System (BeFS) driver");
+MODULE_AUTHOR("Will Dyson");
+MODULE_LICENSE("GPL");
+
+/* The units the vfs expects inode->i_blocks to be in */
+#define VFS_BLOCK_SIZE 512
+
+static int befs_readdir(struct file *, void *, filldir_t);
+static int befs_get_block(struct inode *, long, struct buffer_head *, int);
+static int befs_readpage(struct file *file, struct page *page);
+static int befs_bmap(struct address_space *mapping, long block);
+static struct dentry *befs_lookup(struct inode *, struct dentry *);
+static void befs_read_inode(struct inode *ino);
+static void befs_clear_inode(struct inode *ino);
+static int befs_init_inodecache(void);
+static void befs_destroy_inodecache(void);
+static int befs_readlink(struct dentry *, char *, int);
+static int befs_follow_link(struct dentry *, struct nameidata *nd);
+static int befs_utf2nls(struct super_block *sb, const char *in, int in_len,
+			char **out, int *out_len);
+static int befs_nls2utf(struct super_block *sb, const char *in, int in_len,
+			char **out, int *out_len);
+static void befs_put_super(struct super_block *);
+static struct super_block *befs_read_super(struct super_block *, void *, int);
+static int befs_remount(struct super_block *, int *, char *);
+static int befs_statfs(struct super_block *, struct statfs *);
+static int parse_options(char *, befs_mount_options *);
+
+static const struct super_operations befs_sops = {
+	read_inode:befs_read_inode,	/* initialize & read inode */
+	clear_inode:befs_clear_inode,	/* uninit inode */
+	put_super:befs_put_super,	/* uninit super */
+	statfs:befs_statfs,	/* statfs */
+	remount_fs:befs_remount	/* remount_fs */
+};
+
+/* slab cache for befs_inode_info objects */
+static kmem_cache_t *befs_inode_cachep;
+
+struct file_operations befs_dir_operations = {
+	read:generic_read_dir,	/* read */
+	readdir:befs_readdir,	/* readdir */
+};
+
+struct inode_operations befs_dir_inode_operations = {
+	lookup:befs_lookup,	/* lookup */
+};
+
+struct file_operations befs_file_operations = {
+	llseek:default_llseek,
+	read:generic_file_read,	/* read */
+	mmap:generic_file_mmap,	/* mmap */
+};
+
+struct address_space_operations befs_aops = {
+	readpage:befs_readpage,
+	sync_page:block_sync_page,
+	bmap:befs_bmap,
+};
+
+static struct inode_operations befs_symlink_inode_operations = {
+	readlink:befs_readlink,	/* readlink */
+	follow_link:befs_follow_link	/* follow_link */
+};
+
+/* 
+ * Called by generic_file_read() to read a page of data
+ * 
+ * In turn, simply calls a generic block read function and
+ * passes it the address of befs_get_block, for mapping file
+ * positions to disk blocks.
+ */
+static int
+befs_readpage(struct file *file, struct page *page)
+{
+	return block_read_full_page(page, befs_get_block);
+}
+
+static int
+befs_bmap(struct address_space *mapping, long block)
+{
+	return generic_block_bmap(mapping, block, befs_get_block);
+}
+
+/* 
+ * Generic function to map a file position (block) to a 
+ * disk offset (passed back in bh_result).
+ *
+ * Used by many higher level functions.
+ *
+ * Calls befs_fblock2brun() in datastream.c to do the real work.
+ *
+ * -WD 10-26-01
+ */
+
+static int
+befs_get_block(struct inode *inode, long block,
+	       struct buffer_head *bh_result, int create)
+{
+	struct super_block *sb = inode->i_sb;
+	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
+	befs_block_run run = BAD_IADDR;
+	int res = 0;
+	ulong disk_off;
+
+	befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
+		   inode->i_ino, block);
+
+	if (block < 0) {
+		befs_error(sb, "befs_get_block() was asked for a block "
+			   "number less than zero: block %ld in inode %lu",
+			   block, inode->i_ino);
+		return -EIO;
+	}
+
+	if (create) {
+		befs_error(sb, "befs_get_block() was asked to write to "
+			   "block %ld in inode %lu", block, inode->i_ino);
+		return -EPERM;
+	}
+
+	res = befs_fblock2brun(sb, ds, block, &run);
+	if (res != BEFS_OK) {
+		befs_error(sb,
+			   "<--- befs_get_block() for inode %lu, block "
+			   "%ld ERROR", inode->i_ino, block);
+		return -EFBIG;
+	}
+
+	disk_off = (ulong) iaddr2blockno(sb, &run);
+
+	bh_result->b_dev = inode->i_dev;
+	bh_result->b_blocknr = disk_off;
+	bh_result->b_state |= (1UL << BH_Mapped);
+
+	befs_debug(sb, "<--- befs_get_block() for inode %lu, block %ld, "
+		   "disk address %lu", inode->i_ino, block, disk_off);
+
+	return 0;
+}
+
+static struct dentry *
+befs_lookup(struct inode *dir, struct dentry *dentry)
+{
+	struct inode *inode = NULL;
+	struct super_block *sb = dir->i_sb;
+	befs_data_stream *ds = &BEFS_I(dir)->i_data.ds;
+	befs_off_t offset;
+	int ret;
+	int utfnamelen;
+	char *utfname;
+	const char *name = dentry->d_name.name;
+
+	befs_debug(sb, "---> befs_lookup() "
+		   "name %s inode %ld", dentry->d_name.name, dir->i_ino);
+
+	/* Convert to UTF-8 */
+	if (BEFS_SB(sb)->nls) {
+		ret =
+		    befs_nls2utf(sb, name, strlen(name), &utfname, &utfnamelen);
+		if (ret < 0) {
+			befs_debug(sb, "<--- befs_lookup() ERROR");
+			return ERR_PTR(ret);
+		}
+		ret = befs_btree_find(sb, ds, utfname, &offset);
+		kfree(utfname);
+
+	} else {
+		ret = befs_btree_find(sb, ds, dentry->d_name.name, &offset);
+	}
+
+	if (ret == BEFS_BT_NOT_FOUND) {
+		befs_debug(sb, "<--- befs_lookup() %s not found",
+			   dentry->d_name.name);
+		return ERR_PTR(-ENOENT);
+
+	} else if (ret != BEFS_OK || offset == 0) {
+		befs_warning(sb, "<--- befs_lookup() Error");
+		return ERR_PTR(-ENODATA);
+	}
+
+	inode = iget(dir->i_sb, (ino_t) offset);
+	if (!inode)
+		return ERR_PTR(-EACCES);
+
+	d_add(dentry, inode);
+
+	befs_debug(sb, "<--- befs_lookup()");
+
+	return NULL;
+}
+
+static int
+befs_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+	struct inode *inode = filp->f_dentry->d_inode;
+	struct super_block *sb = inode->i_sb;
+	befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
+	befs_off_t value;
+	int result;
+	size_t keysize;
+	unsigned char d_type;
+	char keybuf[BEFS_NAME_LEN + 1];
+	char *nlsname;
+	int nlsnamelen;
+	const char *dirname = filp->f_dentry->d_name.name;
+
+	befs_debug(sb, "---> befs_readdir() "
+		   "name %s, inode %ld, filp->f_pos %Ld",
+		   dirname, inode->i_ino, filp->f_pos);
+
+	result = befs_btree_read(sb, ds, filp->f_pos, BEFS_NAME_LEN + 1,
+				 keybuf, &keysize, &value);
+
+	if (result == BEFS_ERR) {
+		befs_debug(sb, "<--- befs_readdir() ERROR");
+		befs_error(sb, "IO error reading %s (inode %lu)",
+			   dirname, inode->i_ino);
+		return -EIO;
+
+	} else if (result == BEFS_BT_END) {
+		befs_debug(sb, "<--- befs_readdir() END");
+		return 0;
+
+	} else if (result == BEFS_BT_EMPTY) {
+		befs_debug(sb, "<--- befs_readdir() Empty directory");
+		return 0;
+	}
+
+	d_type = DT_UNKNOWN;
+
+	/* Convert to NLS */
+	if (BEFS_SB(sb)->nls) {
+		result =
+		    befs_utf2nls(sb, keybuf, keysize, &nlsname, &nlsnamelen);
+		if (result < 0) {
+			befs_debug(sb, "<--- befs_readdir() ERROR");
+			return result;
+		}
+		result = filldir(dirent, nlsname, nlsnamelen, filp->f_pos,
+				 (ino_t) value, d_type);
+		kfree(nlsname);
+
+	} else {
+		result = filldir(dirent, keybuf, keysize, filp->f_pos,
+				 (ino_t) value, d_type);
+	}
+
+	filp->f_pos++;
+
+	befs_debug(sb, "<--- befs_readdir() filp->f_pos %Ld", filp->f_pos);
+
+	return 0;
+}
+
+static void
+befs_clear_inode(struct inode *inode)
+{
+	befs_inode_info *b_ino = BEFS_I(inode);
+	inode->u.generic_ip = NULL;
+
+	if (b_ino) {
+		kmem_cache_free(befs_inode_cachep, b_ino);
+	}
+	return;
+}
+
+static void
+befs_read_inode(struct inode *inode)
+{
+	struct buffer_head *bh = NULL;
+	befs_inode *raw_inode = NULL;
+
+	struct super_block *sb = inode->i_sb;
+	befs_sb_info *befs_sb = BEFS_SB(sb);
+	befs_inode_info *befs_ino = NULL;
+
+	befs_debug(sb, "---> befs_read_inode() " "inode = %lu", inode->i_ino);
+
+	inode->u.generic_ip = kmem_cache_alloc(befs_inode_cachep, GFP_NOFS);
+	if (inode->u.generic_ip == NULL) {
+		befs_error(sb, "Unable to allocate memory for private "
+			   "portion of inode %lu.", inode->i_ino);
+		goto unaquire_none;
+	}
+	befs_ino = BEFS_I(inode);
+
+	/* convert from vfs's inode number to befs's inode number */
+	befs_ino->i_inode_num = blockno2iaddr(sb, inode->i_ino);
+
+	befs_debug(sb, "  real inode number [%u, %hu, %hu]",
+		   befs_ino->i_inode_num.allocation_group,
+		   befs_ino->i_inode_num.start, befs_ino->i_inode_num.len);
+
+	bh = befs_bread_iaddr(sb, befs_ino->i_inode_num);
+	if (!bh) {
+		befs_error(sb, "unable to read inode block - "
+			   "inode = %lu", inode->i_ino);
+		goto unaquire_ino_info;
+	}
+
+	raw_inode = (befs_inode *) bh->b_data;
+
+	befs_dump_inode(sb, raw_inode);
+
+	if (befs_check_inode(sb, raw_inode, inode->i_ino) != BEFS_OK) {
+		befs_error(sb, "Bad inode: %lu", inode->i_ino);
+		goto unaquire_bh;
+	}
+
+	inode->i_mode = (umode_t) fs32_to_cpu(sb, raw_inode->mode);
+
+	/*
+	 * set uid and gid.  But since current BeOS is single user OS, so
+	 * you can change by "uid" or "gid" options.
+	 */
+
+	inode->i_uid = befs_sb->mount_opts.use_uid ?
+	    befs_sb->mount_opts.uid : (uid_t) fs32_to_cpu(sb, raw_inode->uid);
+	inode->i_gid = befs_sb->mount_opts.use_gid ?
+	    befs_sb->mount_opts.gid : (gid_t) fs32_to_cpu(sb, raw_inode->gid);
+
+	inode->i_nlink = 1;
+
+	/*
+	 * BEFS's time is 64 bits, but current VFS is 32 bits...
+	 * BEFS don't have access time. Nor inode change time. VFS
+	 * doesn't have creation time.
+	 */
+
+	inode->i_mtime =
+	    (time_t) (fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16);
+	inode->i_ctime = inode->i_mtime;
+	inode->i_atime = inode->i_mtime;
+
+/* Bloody hell, Linus. Why add this in a stable series? */
+#if LINUX_VERSION_CODE > KERNEL_VERSION(2,4,9)
+	inode->i_blkbits = befs_sb->block_shift;
+#endif
+
+	inode->i_blksize = befs_sb->block_size;
+
+	befs_ino->i_inode_num = fsrun_to_cpu(sb, raw_inode->inode_num);
+	befs_ino->i_parent = fsrun_to_cpu(sb, raw_inode->parent);
+	befs_ino->i_attribute = fsrun_to_cpu(sb, raw_inode->attributes);
+	befs_ino->i_flags = fs32_to_cpu(sb, raw_inode->flags);
+
+	if (S_ISLNK(inode->i_mode) && !(inode->i_flags & BEFS_LONG_SYMLINK)) {
+		inode->i_size = 0;
+		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
+		strncpy(befs_ino->i_data.symlink, raw_inode->data.symlink,
+			BEFS_SYMLINK_LEN);
+	} else {
+		int num_blks;
+
+		befs_ino->i_data.ds =
+		    fsds_to_cpu(sb, raw_inode->data.datastream);
+
+		num_blks = befs_count_blocks(sb, &befs_ino->i_data.ds);
+		inode->i_blocks =
+		    num_blks * (befs_sb->block_size / VFS_BLOCK_SIZE);
+		inode->i_size = befs_ino->i_data.ds.size;
+	}
+
+	inode->i_mapping->a_ops = &befs_aops;
+
+	if (S_ISREG(inode->i_mode)) {
+		inode->i_fop = &befs_file_operations;
+	} else if (S_ISDIR(inode->i_mode)) {
+		inode->i_op = &befs_dir_inode_operations;
+		inode->i_fop = &befs_dir_operations;
+	} else if (S_ISLNK(inode->i_mode)) {
+		inode->i_op = &befs_symlink_inode_operations;
+	} else {
+		befs_error(sb, "Inode %lu is not a regular file, "
+			   "directory or symlink. THAT IS WRONG! BeFS has no "
+			   "on disk special files", inode->i_ino);
+		goto unaquire_bh;
+	}
+
+	brelse(bh);
+	befs_debug(sb, "<--- befs_read_inode()");
+	return;
+
+      unaquire_bh:
+	brelse(bh);
+
+      unaquire_ino_info:
+	kmem_cache_free(befs_inode_cachep, inode->u.generic_ip);
+
+      unaquire_none:
+	make_bad_inode(inode);
+	inode->u.generic_ip = NULL;
+	befs_debug(sb, "<--- befs_read_inode() - Bad inode");
+	return;
+}
+
+/* Initialize the inode cache. Called at fs setup.
+ * 
+ * Taken from NFS implementation by Al Viro.
+ */
+static int
+befs_init_inodecache(void)
+{
+	befs_inode_cachep = kmem_cache_create("befs_inode_cache",
+					      sizeof (struct befs_inode_info),
+					      0, SLAB_HWCACHE_ALIGN,
+					      NULL, NULL);
+	if (befs_inode_cachep == NULL) {
+		printk(KERN_ERR "befs_init_inodecache: "
+		       "Couldn't initalize inode slabcache\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/* Called at fs teardown.
+ * 
+ * Taken from NFS implementation by Al Viro.
+ */
+static void
+befs_destroy_inodecache(void)
+{
+	if (kmem_cache_destroy(befs_inode_cachep))
+		printk(KERN_ERR "befs_destroy_inodecache: "
+		       "not all structures were freed\n");
+}
+
+/*
+ * The inode of symbolic link is different to data stream.
+ * The data stream become link name. Unless the LONG_SYMLINK
+ * flag is set.
+ */
+static int
+befs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	struct super_block *sb = dentry->d_sb;
+	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
+	char *link;
+	int res;
+
+	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
+		befs_data_stream *data = &befs_ino->i_data.ds;
+		befs_off_t linklen = data->size;
+
+		befs_debug(sb, "Follow long symlink");
+
+		link = kmalloc(linklen, GFP_NOFS);
+		if (link == NULL)
+			return -ENOMEM;
+
+		if (befs_read_lsymlink(sb, data, link, linklen) != linklen) {
+			kfree(link);
+			befs_error(sb, "Failed to read entire long symlink");
+			return -EIO;
+		}
+
+		res = vfs_follow_link(nd, link);
+
+		kfree(link);
+	} else {
+		link = befs_ino->i_data.symlink;
+		res = vfs_follow_link(nd, link);
+	}
+
+	return res;
+}
+
+static int
+befs_readlink(struct dentry *dentry, char *buffer, int buflen)
+{
+	struct super_block *sb = dentry->d_sb;
+	befs_inode_info *befs_ino = BEFS_I(dentry->d_inode);
+	char *link;
+	int res;
+
+	if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
+		befs_data_stream *data = &befs_ino->i_data.ds;
+		befs_off_t linklen = data->size;
+
+		befs_debug(sb, "Read long symlink");
+
+		link = kmalloc(linklen, GFP_NOFS);
+		if (link == NULL)
+			return -ENOMEM;
+
+		if (befs_read_lsymlink(sb, data, link, linklen) != linklen) {
+			kfree(link);
+			befs_error(sb, "Failed to read entire long symlink");
+			return -EIO;
+		}
+
+		res = vfs_readlink(dentry, buffer, buflen, link);
+
+		kfree(link);
+	} else {
+		link = befs_ino->i_data.symlink;
+		res = vfs_readlink(dentry, buffer, buflen, link);
+	}
+
+	return res;
+}
+
+/*
+ * UTF-8 to NLS charset  convert routine
+ *
+ * Changed 8/10/01 by Will Dyson. Now use uni2char() / char2uni() rather than
+ * the nls tables directly
+ */
+
+static int
+befs_utf2nls(struct super_block *sb, const char *in,
+	     int in_len, char **out, int *out_len)
+{
+	struct nls_table *nls = BEFS_SB(sb)->nls;
+	int i, o;
+	wchar_t uni;
+	int unilen, utflen;
+	char *result;
+	int maxlen = in_len; /* The utf8->nls conversion cant make more chars */
+
+	befs_debug(sb, "---> utf2nls()");
+
+	if (!nls) {
+		befs_error(sb, "befs_utf2nls called with no NLS table loaded");
+		return -EINVAL;
+	}
+
+	*out = result = kmalloc(maxlen, GFP_NOFS);
+	if (!*out) {
+		befs_error(sb, "befs_utf2nls() cannot allocate memory");
+		*out_len = 0;
+		return -ENOMEM;
+	}
+
+	for (i = o = 0; i < in_len; i += utflen, o += unilen) {
+
+		/* convert from UTF-8 to Unicode */
+		utflen = utf8_mbtowc(&uni, &in[i], in_len - i);
+		if (utflen < 0) {
+			goto conv_err;
+		}
+
+		/* convert from Unicode to nls */
+		unilen = nls->uni2char(uni, &result[o], 1);
+		if (unilen < 0) {
+			goto conv_err;
+		}
+	}
+	result[o] = '\0';
+
+	befs_debug(sb, "<--- utf2nls()");
+
+	return o;
+	*out_len = o;
+
+      conv_err:
+	befs_error(sb, "Name using charecter set %s contains a charecter that "
+		   "cannot be converted to unicode.", nls->charset);
+	befs_debug(sb, "<--- utf2nls()");
+	kfree(result);
+	return -EILSEQ;
+}
+
+/**
+ * befs_nls2utf - Convert NLS string to utf8 encodeing
+ * @sb: Superblock
+ * @src: Input string buffer in NLS format
+ * @srclen: Length of input string in bytes
+ * @dest: The output string in UTF8 format
+ * @destlen: Length of the output buffer
+ * 
+ * Converts input string @src, which is in the format of the loaded NLS map,
+ * into a utf8 string.
+ * 
+ * The destination string @dest is allocated by this function and the caller is
+ * responsible for freeing it with kfree()
+ * 
+ * On return, *@destlen is the length of @dest in bytes.
+ *
+ * On success, the return value is the number of utf8 charecters written to
+ * the ouput buffer @dest.
+ *  
+ * On Failure, a negative number coresponding to the error code is returned.
+ */
+
+static int
+befs_nls2utf(struct super_block *sb, const char *in,
+	     int in_len, char **out, int *out_len)
+{
+	struct nls_table *nls = BEFS_SB(sb)->nls;
+	int i, o;
+	wchar_t uni;
+	int unilen, utflen;
+	char *result;
+	int maxlen = 3 * in_len;
+
+	befs_debug(sb, "---> nls2utf()\n");
+
+	if (!nls) {
+		befs_error(sb, "befs_nls2utf called with no NLS table loaded.");
+		return -EINVAL;
+	}
+
+	*out = result = kmalloc(maxlen, GFP_NOFS);
+	if (!*out) {
+		befs_error(sb, "befs_nls2utf() cannot allocate memory");
+		*out_len = 0;
+		return -ENOMEM;
+	}
+
+	for (i = o = 0; i < in_len; i += unilen, o += utflen) {
+
+		/* convert from nls to unicode */
+		unilen = nls->char2uni(&in[i], in_len - i, &uni);
+		if (unilen < 0) {
+			goto conv_err;
+		}
+
+		/* convert from unicode to UTF-8 */
+		utflen = utf8_wctomb(&result[o], uni, 3);
+		if (utflen <= 0) {
+			goto conv_err;
+		}
+	}
+
+	result[o] = '\0';
+	*out_len = o;
+
+	befs_debug(sb, "<--- nls2utf()");
+
+	return i;
+
+      conv_err:
+	befs_error(sb, "Name using charecter set %s contains a charecter that "
+		   "cannot be converted to unicode.", nls->charset);
+	befs_debug(sb, "<--- nls2utf()");
+	kfree(result);
+	return -EILSEQ;
+}
+
+static int
+parse_options(char *options, befs_mount_options * opts)
+{
+	char *this_char;
+	char *value;
+	int ret = 1;
+
+	/* Initialize options */
+	opts->uid = 0;
+	opts->gid = 0;
+	opts->use_uid = 0;
+	opts->use_gid = 0;
+	opts->iocharset = NULL;
+	opts->debug = 0;
+
+	if (!options)
+		return ret;
+
+	for (this_char = strtok(options, ","); this_char != NULL;
+	     this_char = strtok(NULL, ",")) {
+
+		if ((value = strchr(this_char, '=')) != NULL)
+			*value++ = 0;
+
+		if (!strcmp(this_char, "uid")) {
+			if (!value || !*value) {
+				ret = 0;
+			} else {
+				opts->uid = simple_strtoul(value, &value, 0);
+				opts->use_uid = 1;
+				if (*value) {
+					printk(KERN_ERR "BEFS: Invalid uid "
+					       "option: %s\n", value);
+					ret = 0;
+				}
+			}
+		} else if (!strcmp(this_char, "gid")) {
+			if (!value || !*value)
+				ret = 0;
+			else {
+				opts->gid = simple_strtoul(value, &value, 0);
+				opts->use_gid = 1;
+				if (*value) {
+					printk(KERN_ERR
+					       "BEFS: Invalid gid option: "
+					       "%s\n", value);
+					ret = 0;
+				}
+			}
+		} else if (!strcmp(this_char, "iocharset") && value) {
+			char *p = value;
+			int len;
+
+			while (*value && *value != ',')
+				value++;
+			len = value - p;
+			if (len) {
+				char *buffer = kmalloc(len + 1, GFP_NOFS);
+				if (buffer) {
+					opts->iocharset = buffer;
+					memcpy(buffer, p, len);
+					buffer[len] = 0;
+
+				} else {
+					printk(KERN_ERR "BEFS: "
+					       "cannot allocate memory\n");
+					ret = 0;
+				}
+			}
+		} else if (!strcmp(this_char, "debug")) {
+			opts->debug = 1;
+		}
+	}
+
+	return ret;
+}
+
+/* This function has the responsibiltiy of getting the
+ * filesystem ready for unmounting. 
+ * Basicly, we free everything that we allocated in
+ * befs_read_inode
+ */
+static void
+befs_put_super(struct super_block *sb)
+{
+	if (BEFS_SB(sb)->mount_opts.iocharset) {
+		kfree(BEFS_SB(sb)->mount_opts.iocharset);
+		BEFS_SB(sb)->mount_opts.iocharset = NULL;
+	}
+
+	if (BEFS_SB(sb)->nls) {
+		unload_nls(BEFS_SB(sb)->nls);
+		BEFS_SB(sb)->nls = NULL;
+	}
+
+	if (sb->u.generic_sbp) {
+		kfree(sb->u.generic_sbp);
+		sb->u.generic_sbp = NULL;
+	}
+	return;
+}
+
+/* Allocate private field of the superblock, fill it.
+ *
+ * Finish filling the public superblock fields
+ * Make the root directory
+ * Load a set of NLS translations if needed.
+ */
+static struct super_block *
+befs_read_super(struct super_block *sb, void *data, int silent)
+{
+	struct buffer_head *bh;
+	befs_sb_info *befs_sb;
+	befs_super_block *disk_sb;
+	int blocksize;
+
+	const unsigned long sb_block = 0;
+	const off_t x86_sb_off = 512;
+
+	sb->u.generic_sbp = kmalloc(sizeof (struct befs_sb_info), GFP_NOFS);
+	if (sb->u.generic_sbp == NULL) {
+		printk(KERN_ERR
+		       "BeFS(%s): Unable to allocate memory for private "
+		       "portion of superblock. Bailing.\n",
+		       kdevname(sb->s_dev));
+		goto unaquire_none;
+	}
+	befs_sb = BEFS_SB(sb);
+
+	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
+		befs_error(sb, "cannot parse mount options");
+		goto unaquire_priv_sbp;
+	}
+
+	befs_debug(sb, "---> befs_read_super()");
+
+#ifndef CONFIG_BEFS_RW
+	if (!(sb->s_flags & MS_RDONLY)) {
+		befs_warning(sb,
+			     "No write support. Marking filesystem read-only");
+		sb->s_flags |= MS_RDONLY;
+	}
+#endif				/* CONFIG_BEFS_RW */
+
+	/*
+	 * Set dummy blocksize to read super block.
+	 * Will be set to real fs blocksize later.
+	 *
+	 * Linux 2.4.10 and later refuse to read blocks smaller than
+	 * the hardsect size for the device. But we also need to read at 
+	 * least 1k to get the second 512 bytes of the volume.
+	 * -WD 10-26-01
+	 */
+	blocksize = max_t(int, get_hardsect_size(sb->s_dev), 1024);
+	set_blocksize(sb->s_dev, blocksize);
+
+	if (!(bh = bread(sb->s_dev, sb_block, blocksize))) {
+		befs_error(sb, "unable to read superblock");
+		goto unaquire_priv_sbp;
+	}
+
+	/* account for offset of super block on x86 */
+	disk_sb = (befs_super_block *) bh->b_data;
+	if ((le32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1) ||
+	    (be32_to_cpu(disk_sb->magic1) == BEFS_SUPER_MAGIC1)) {
+		befs_debug(sb, "Using PPC superblock location");
+	} else {
+		befs_debug(sb, "Using x86 superblock location");
+		disk_sb =
+		    (befs_super_block *) ((void *) bh->b_data + x86_sb_off);
+	}
+
+	if (befs_load_sb(sb, disk_sb) != BEFS_OK)
+		goto unaquire_bh;
+
+	befs_dump_super_block(sb, disk_sb);
+
+	brelse(bh);
+
+	if (befs_check_sb(sb) != BEFS_OK)
+		goto unaquire_priv_sbp;
+
+	/*
+	 * set up enough so that it can read an inode
+	 * Fill in kernel superblock fields from private sb
+	 */
+	sb->s_magic = BEFS_SUPER_MAGIC;
+	sb->s_blocksize = (ulong) befs_sb->block_size;
+	sb->s_blocksize_bits = (unsigned char) befs_sb->block_shift;
+	sb->s_op = (struct super_operations *) &befs_sops;
+	sb->s_root =
+	    d_alloc_root(iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir))));
+	if (!sb->s_root) {
+		befs_error(sb, "get root inode failed");
+		goto unaquire_priv_sbp;
+	}
+
+	/* load nls library */
+	if (befs_sb->mount_opts.iocharset) {
+		befs_debug(sb, "Loading nls: %s",
+			   befs_sb->mount_opts.iocharset);
+		befs_sb->nls = load_nls(befs_sb->mount_opts.iocharset);
+		if (!befs_sb->nls) {
+			befs_warning(sb, "Cannot load nls %s"
+				     "loding default nls",
+				     befs_sb->mount_opts.iocharset);
+			befs_sb->nls = load_nls_default();
+		}
+	}
+
+	/* Set real blocksize of fs */
+	set_blocksize(sb->s_dev, (int) befs_sb->block_size);
+
+	return sb;
+/*****************/
+      unaquire_bh:
+	brelse(bh);
+
+      unaquire_priv_sbp:
+	kfree(sb->u.generic_sbp);
+
+      unaquire_none:
+	sb->s_dev = 0;
+	sb->u.generic_sbp = NULL;
+	return NULL;
+}
+
+static int
+befs_remount(struct super_block *sb, int *flags, char *data)
+{
+	if (!(*flags & MS_RDONLY))
+		return -EINVAL;
+	return 0;
+}
+
+static int
+befs_statfs(struct super_block *sb, struct statfs *buf)
+{
+
+	befs_debug(sb, "---> befs_statfs()");
+
+	buf->f_type = BEFS_SUPER_MAGIC;
+	buf->f_bsize = sb->s_blocksize;
+	buf->f_blocks = BEFS_SB(sb)->num_blocks;
+	buf->f_bfree = BEFS_SB(sb)->num_blocks - BEFS_SB(sb)->used_blocks;
+	buf->f_bavail = buf->f_bfree;
+	buf->f_files = 0;	/* UNKNOWN */
+	buf->f_ffree = 0;	/* UNKNOWN */
+	buf->f_namelen = BEFS_NAME_LEN;
+
+	befs_debug(sb, "<--- befs_statfs()");
+
+	return 0;
+}
+
+/*
+	Makes a variable of type file_system_type, 
+	named befs_fs_tipe, identified by the "befs" string,
+	and containing a reference to the befs_read_super function
+	
+	Macro declared in <linux/fs.h>
+*/
+static DECLARE_FSTYPE_DEV(befs_fs_type, "befs", befs_read_super);
+
+static int __init
+init_befs_fs(void)
+{
+	int err;
+
+	printk(KERN_INFO "BeFS version: %s\n", BEFS_VERSION);
+
+	err = befs_init_inodecache();
+	if (err)
+		return err;
+
+	return register_filesystem(&befs_fs_type);
+}
+
+static void __exit
+exit_befs_fs(void)
+{
+	befs_destroy_inodecache();
+
+	unregister_filesystem(&befs_fs_type);
+}
+
+/*
+Macros that typecheck the init and exit functions,
+ensures that they are called at init and cleanup,
+and eliminates warnings about unused functions.
+*/
+module_init(init_befs_fs)
+    module_exit(exit_befs_fs)
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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)