Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1027 insertions, 0 deletions

diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c
new file mode 100644
index 0000000000..9a16a51fbb
--- /dev/null
+++ b/fs/befs/linuxvfs.c
@@ -0,0 +1,1027 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/fs/befs/linuxvfs.c
+ *
+ * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/stat.h>
+#include <linux/nls.h>
+#include <linux/buffer_head.h>
+#include <linux/vfs.h>
+#include <linux/parser.h>
+#include <linux/namei.h>
+#include <linux/sched.h>
+#include <linux/cred.h>
+#include <linux/exportfs.h>
+#include <linux/seq_file.h>
+#include <linux/blkdev.h>
+
+#include "befs.h"
+#include "btree.h"
+#include "inode.h"
+#include "datastream.h"
+#include "super.h"
+#include "io.h"
+
+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 *, struct dir_context *);
+static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
+static int befs_read_folio(struct file *file, struct folio *folio);
+static sector_t befs_bmap(struct address_space *mapping, sector_t block);
+static struct dentry *befs_lookup(struct inode *, struct dentry *,
+				  unsigned int);
+static struct inode *befs_iget(struct super_block *, unsigned long);
+static struct inode *befs_alloc_inode(struct super_block *sb);
+static void befs_free_inode(struct inode *inode);
+static void befs_destroy_inodecache(void);
+static int befs_symlink_read_folio(struct file *, struct folio *);
+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 int befs_remount(struct super_block *, int *, char *);
+static int befs_statfs(struct dentry *, struct kstatfs *);
+static int befs_show_options(struct seq_file *, struct dentry *);
+static int parse_options(char *, struct befs_mount_options *);
+static struct dentry *befs_fh_to_dentry(struct super_block *sb,
+				struct fid *fid, int fh_len, int fh_type);
+static struct dentry *befs_fh_to_parent(struct super_block *sb,
+				struct fid *fid, int fh_len, int fh_type);
+static struct dentry *befs_get_parent(struct dentry *child);
+
+static const struct super_operations befs_sops = {
+	.alloc_inode	= befs_alloc_inode,	/* allocate a new inode */
+	.free_inode	= befs_free_inode, /* deallocate an inode */
+	.put_super	= befs_put_super,	/* uninit super */
+	.statfs		= befs_statfs,	/* statfs */
+	.remount_fs	= befs_remount,
+	.show_options	= befs_show_options,
+};
+
+/* slab cache for befs_inode_info objects */
+static struct kmem_cache *befs_inode_cachep;
+
+static const struct file_operations befs_dir_operations = {
+	.read		= generic_read_dir,
+	.iterate_shared	= befs_readdir,
+	.llseek		= generic_file_llseek,
+};
+
+static const struct inode_operations befs_dir_inode_operations = {
+	.lookup		= befs_lookup,
+};
+
+static const struct address_space_operations befs_aops = {
+	.read_folio	= befs_read_folio,
+	.bmap		= befs_bmap,
+};
+
+static const struct address_space_operations befs_symlink_aops = {
+	.read_folio	= befs_symlink_read_folio,
+};
+
+static const struct export_operations befs_export_operations = {
+	.fh_to_dentry	= befs_fh_to_dentry,
+	.fh_to_parent	= befs_fh_to_parent,
+	.get_parent	= befs_get_parent,
+};
+
+/*
+ * Called by generic_file_read() to read a folio 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_read_folio(struct file *file, struct folio *folio)
+{
+	return block_read_full_folio(folio, befs_get_block);
+}
+
+static sector_t
+befs_bmap(struct address_space *mapping, sector_t 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.
+ */
+
+static int
+befs_get_block(struct inode *inode, sector_t 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;
+	ulong disk_off;
+
+	befs_debug(sb, "---> befs_get_block() for inode %lu, block %ld",
+		   (unsigned long)inode->i_ino, (long)block);
+	if (create) {
+		befs_error(sb, "befs_get_block() was asked to write to "
+			   "block %ld in inode %lu", (long)block,
+			   (unsigned long)inode->i_ino);
+		return -EPERM;
+	}
+
+	res = befs_fblock2brun(sb, ds, block, &run);
+	if (res != BEFS_OK) {
+		befs_error(sb,
+			   "<--- %s for inode %lu, block %ld ERROR",
+			   __func__, (unsigned long)inode->i_ino,
+			   (long)block);
+		return -EFBIG;
+	}
+
+	disk_off = (ulong) iaddr2blockno(sb, &run);
+
+	map_bh(bh_result, inode->i_sb, disk_off);
+
+	befs_debug(sb, "<--- %s for inode %lu, block %ld, disk address %lu",
+		  __func__, (unsigned long)inode->i_ino, (long)block,
+		  (unsigned long)disk_off);
+
+	return 0;
+}
+
+static struct dentry *
+befs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
+{
+	struct inode *inode;
+	struct super_block *sb = dir->i_sb;
+	const 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, "---> %s name %pd inode %ld", __func__,
+		   dentry, 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, "<--- %s ERROR", __func__);
+			return ERR_PTR(ret);
+		}
+		ret = befs_btree_find(sb, ds, utfname, &offset);
+		kfree(utfname);
+
+	} else {
+		ret = befs_btree_find(sb, ds, name, &offset);
+	}
+
+	if (ret == BEFS_BT_NOT_FOUND) {
+		befs_debug(sb, "<--- %s %pd not found", __func__, dentry);
+		inode = NULL;
+	} else if (ret != BEFS_OK || offset == 0) {
+		befs_error(sb, "<--- %s Error", __func__);
+		inode = ERR_PTR(-ENODATA);
+	} else {
+		inode = befs_iget(dir->i_sb, (ino_t) offset);
+	}
+	befs_debug(sb, "<--- %s", __func__);
+
+	return d_splice_alias(inode, dentry);
+}
+
+static int
+befs_readdir(struct file *file, struct dir_context *ctx)
+{
+	struct inode *inode = file_inode(file);
+	struct super_block *sb = inode->i_sb;
+	const befs_data_stream *ds = &BEFS_I(inode)->i_data.ds;
+	befs_off_t value;
+	int result;
+	size_t keysize;
+	char keybuf[BEFS_NAME_LEN + 1];
+
+	befs_debug(sb, "---> %s name %pD, inode %ld, ctx->pos %lld",
+		  __func__, file, inode->i_ino, ctx->pos);
+
+	while (1) {
+		result = befs_btree_read(sb, ds, ctx->pos, BEFS_NAME_LEN + 1,
+					 keybuf, &keysize, &value);
+
+		if (result == BEFS_ERR) {
+			befs_debug(sb, "<--- %s ERROR", __func__);
+			befs_error(sb, "IO error reading %pD (inode %lu)",
+				   file, inode->i_ino);
+			return -EIO;
+
+		} else if (result == BEFS_BT_END) {
+			befs_debug(sb, "<--- %s END", __func__);
+			return 0;
+
+		} else if (result == BEFS_BT_EMPTY) {
+			befs_debug(sb, "<--- %s Empty directory", __func__);
+			return 0;
+		}
+
+		/* Convert to NLS */
+		if (BEFS_SB(sb)->nls) {
+			char *nlsname;
+			int nlsnamelen;
+
+			result =
+			    befs_utf2nls(sb, keybuf, keysize, &nlsname,
+					 &nlsnamelen);
+			if (result < 0) {
+				befs_debug(sb, "<--- %s ERROR", __func__);
+				return result;
+			}
+			if (!dir_emit(ctx, nlsname, nlsnamelen,
+				      (ino_t) value, DT_UNKNOWN)) {
+				kfree(nlsname);
+				return 0;
+			}
+			kfree(nlsname);
+		} else {
+			if (!dir_emit(ctx, keybuf, keysize,
+				      (ino_t) value, DT_UNKNOWN))
+				return 0;
+		}
+		ctx->pos++;
+	}
+}
+
+static struct inode *
+befs_alloc_inode(struct super_block *sb)
+{
+	struct befs_inode_info *bi;
+
+	bi = alloc_inode_sb(sb, befs_inode_cachep, GFP_KERNEL);
+	if (!bi)
+		return NULL;
+	return &bi->vfs_inode;
+}
+
+static void befs_free_inode(struct inode *inode)
+{
+	kmem_cache_free(befs_inode_cachep, BEFS_I(inode));
+}
+
+static void init_once(void *foo)
+{
+	struct befs_inode_info *bi = (struct befs_inode_info *) foo;
+
+	inode_init_once(&bi->vfs_inode);
+}
+
+static struct inode *befs_iget(struct super_block *sb, unsigned long ino)
+{
+	struct buffer_head *bh;
+	befs_inode *raw_inode;
+	struct befs_sb_info *befs_sb = BEFS_SB(sb);
+	struct befs_inode_info *befs_ino;
+	struct inode *inode;
+
+	befs_debug(sb, "---> %s inode = %lu", __func__, ino);
+
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	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 = sb_bread(sb, inode->i_ino);
+	if (!bh) {
+		befs_error(sb, "unable to read inode block - "
+			   "inode = %lu", inode->i_ino);
+		goto unacquire_none;
+	}
+
+	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 unacquire_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 :
+		make_kuid(&init_user_ns, fs32_to_cpu(sb, raw_inode->uid));
+	inode->i_gid = befs_sb->mount_opts.use_gid ?
+		befs_sb->mount_opts.gid :
+		make_kgid(&init_user_ns, fs32_to_cpu(sb, raw_inode->gid));
+
+	set_nlink(inode, 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.
+	 * Also, the lower 16 bits of the last_modified_time and
+	 * create_time are just a counter to help ensure uniqueness
+	 * for indexing purposes. (PFD, page 54)
+	 */
+
+	inode->i_mtime.tv_sec =
+	    fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16;
+	inode->i_mtime.tv_nsec = 0;   /* lower 16 bits are not a time */
+	inode_set_ctime_to_ts(inode, inode->i_mtime);
+	inode->i_atime = inode->i_mtime;
+
+	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) && !(befs_ino->i_flags & BEFS_LONG_SYMLINK)){
+		inode->i_size = 0;
+		inode->i_blocks = befs_sb->block_size / VFS_BLOCK_SIZE;
+		strscpy(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 = &generic_ro_fops;
+	} 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)) {
+		if (befs_ino->i_flags & BEFS_LONG_SYMLINK) {
+			inode->i_op = &page_symlink_inode_operations;
+			inode_nohighmem(inode);
+			inode->i_mapping->a_ops = &befs_symlink_aops;
+		} else {
+			inode->i_link = befs_ino->i_data.symlink;
+			inode->i_op = &simple_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 unacquire_bh;
+	}
+
+	brelse(bh);
+	befs_debug(sb, "<--- %s", __func__);
+	unlock_new_inode(inode);
+	return inode;
+
+unacquire_bh:
+	brelse(bh);
+
+unacquire_none:
+	iget_failed(inode);
+	befs_debug(sb, "<--- %s - Bad inode", __func__);
+	return ERR_PTR(-EIO);
+}
+
+/* Initialize the inode cache. Called at fs setup.
+ *
+ * Taken from NFS implementation by Al Viro.
+ */
+static int __init
+befs_init_inodecache(void)
+{
+	befs_inode_cachep = kmem_cache_create_usercopy("befs_inode_cache",
+				sizeof(struct befs_inode_info), 0,
+				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
+					SLAB_ACCOUNT),
+				offsetof(struct befs_inode_info,
+					i_data.symlink),
+				sizeof_field(struct befs_inode_info,
+					i_data.symlink),
+				init_once);
+	if (befs_inode_cachep == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/* Called at fs teardown.
+ *
+ * Taken from NFS implementation by Al Viro.
+ */
+static void
+befs_destroy_inodecache(void)
+{
+	/*
+	 * Make sure all delayed rcu free inodes are flushed before we
+	 * destroy cache.
+	 */
+	rcu_barrier();
+	kmem_cache_destroy(befs_inode_cachep);
+}
+
+/*
+ * 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_symlink_read_folio(struct file *unused, struct folio *folio)
+{
+	struct inode *inode = folio->mapping->host;
+	struct super_block *sb = inode->i_sb;
+	struct befs_inode_info *befs_ino = BEFS_I(inode);
+	befs_data_stream *data = &befs_ino->i_data.ds;
+	befs_off_t len = data->size;
+	char *link = folio_address(folio);
+
+	if (len == 0 || len > PAGE_SIZE) {
+		befs_error(sb, "Long symlink with illegal length");
+		goto fail;
+	}
+	befs_debug(sb, "Follow long symlink");
+
+	if (befs_read_lsymlink(sb, data, link, len) != len) {
+		befs_error(sb, "Failed to read entire long symlink");
+		goto fail;
+	}
+	link[len - 1] = '\0';
+	folio_mark_uptodate(folio);
+	folio_unlock(folio);
+	return 0;
+fail:
+	folio_set_error(folio);
+	folio_unlock(folio);
+	return -EIO;
+}
+
+/*
+ * UTF-8 to NLS charset convert routine
+ *
+ * Uses 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;
+	unicode_t uni;
+	int unilen, utflen;
+	char *result;
+	/* The utf8->nls conversion won't make the final nls string bigger
+	 * than the utf one, but if the string is pure ascii they'll have the
+	 * same width and an extra char is needed to save the additional \0
+	 */
+	int maxlen = in_len + 1;
+
+	befs_debug(sb, "---> %s", __func__);
+
+	if (!nls) {
+		befs_error(sb, "%s called with no NLS table loaded", __func__);
+		return -EINVAL;
+	}
+
+	*out = result = kmalloc(maxlen, GFP_NOFS);
+	if (!*out)
+		return -ENOMEM;
+
+	for (i = o = 0; i < in_len; i += utflen, o += unilen) {
+
+		/* convert from UTF-8 to Unicode */
+		utflen = utf8_to_utf32(&in[i], in_len - i, &uni);
+		if (utflen < 0)
+			goto conv_err;
+
+		/* convert from Unicode to nls */
+		if (uni > MAX_WCHAR_T)
+			goto conv_err;
+		unilen = nls->uni2char(uni, &result[o], in_len - o);
+		if (unilen < 0)
+			goto conv_err;
+	}
+	result[o] = '\0';
+	*out_len = o;
+
+	befs_debug(sb, "<--- %s", __func__);
+
+	return o;
+
+conv_err:
+	befs_error(sb, "Name using character set %s contains a character that "
+		   "cannot be converted to unicode.", nls->charset);
+	befs_debug(sb, "<--- %s", __func__);
+	kfree(result);
+	return -EILSEQ;
+}
+
+/**
+ * befs_nls2utf - Convert NLS string to utf8 encodeing
+ * @sb: Superblock
+ * @in: Input string buffer in NLS format
+ * @in_len: Length of input string in bytes
+ * @out: The output string in UTF-8 format
+ * @out_len: Length of the output buffer
+ *
+ * Converts input string @in, which is in the format of the loaded NLS map,
+ * into a utf8 string.
+ *
+ * The destination string @out is allocated by this function and the caller is
+ * responsible for freeing it with kfree()
+ *
+ * On return, *@out_len is the length of @out in bytes.
+ *
+ * On success, the return value is the number of utf8 characters written to
+ * the output buffer @out.
+ *
+ * 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;
+	/*
+	 * There are nls characters that will translate to 3-chars-wide UTF-8
+	 * characters, an additional byte is needed to save the final \0
+	 * in special cases
+	 */
+	int maxlen = (3 * in_len) + 1;
+
+	befs_debug(sb, "---> %s\n", __func__);
+
+	if (!nls) {
+		befs_error(sb, "%s called with no NLS table loaded.",
+			   __func__);
+		return -EINVAL;
+	}
+
+	*out = result = kmalloc(maxlen, GFP_NOFS);
+	if (!*out) {
+		*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 = utf32_to_utf8(uni, &result[o], 3);
+		if (utflen <= 0)
+			goto conv_err;
+	}
+
+	result[o] = '\0';
+	*out_len = o;
+
+	befs_debug(sb, "<--- %s", __func__);
+
+	return i;
+
+conv_err:
+	befs_error(sb, "Name using character set %s contains a character that "
+		   "cannot be converted to unicode.", nls->charset);
+	befs_debug(sb, "<--- %s", __func__);
+	kfree(result);
+	return -EILSEQ;
+}
+
+static struct inode *befs_nfs_get_inode(struct super_block *sb, uint64_t ino,
+					 uint32_t generation)
+{
+	/* No need to handle i_generation */
+	return befs_iget(sb, ino);
+}
+
+/*
+ * Map a NFS file handle to a corresponding dentry
+ */
+static struct dentry *befs_fh_to_dentry(struct super_block *sb,
+				struct fid *fid, int fh_len, int fh_type)
+{
+	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
+				    befs_nfs_get_inode);
+}
+
+/*
+ * Find the parent for a file specified by NFS handle
+ */
+static struct dentry *befs_fh_to_parent(struct super_block *sb,
+				struct fid *fid, int fh_len, int fh_type)
+{
+	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
+				    befs_nfs_get_inode);
+}
+
+static struct dentry *befs_get_parent(struct dentry *child)
+{
+	struct inode *parent;
+	struct befs_inode_info *befs_ino = BEFS_I(d_inode(child));
+
+	parent = befs_iget(child->d_sb,
+			   (unsigned long)befs_ino->i_parent.start);
+	if (IS_ERR(parent))
+		return ERR_CAST(parent);
+
+	return d_obtain_alias(parent);
+}
+
+enum {
+	Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err,
+};
+
+static const match_table_t befs_tokens = {
+	{Opt_uid, "uid=%d"},
+	{Opt_gid, "gid=%d"},
+	{Opt_charset, "iocharset=%s"},
+	{Opt_debug, "debug"},
+	{Opt_err, NULL}
+};
+
+static int
+parse_options(char *options, struct befs_mount_options *opts)
+{
+	char *p;
+	substring_t args[MAX_OPT_ARGS];
+	int option;
+	kuid_t uid;
+	kgid_t gid;
+
+	/* Initialize options */
+	opts->uid = GLOBAL_ROOT_UID;
+	opts->gid = GLOBAL_ROOT_GID;
+	opts->use_uid = 0;
+	opts->use_gid = 0;
+	opts->iocharset = NULL;
+	opts->debug = 0;
+
+	if (!options)
+		return 1;
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token;
+
+		if (!*p)
+			continue;
+
+		token = match_token(p, befs_tokens, args);
+		switch (token) {
+		case Opt_uid:
+			if (match_int(&args[0], &option))
+				return 0;
+			uid = INVALID_UID;
+			if (option >= 0)
+				uid = make_kuid(current_user_ns(), option);
+			if (!uid_valid(uid)) {
+				pr_err("Invalid uid %d, "
+				       "using default\n", option);
+				break;
+			}
+			opts->uid = uid;
+			opts->use_uid = 1;
+			break;
+		case Opt_gid:
+			if (match_int(&args[0], &option))
+				return 0;
+			gid = INVALID_GID;
+			if (option >= 0)
+				gid = make_kgid(current_user_ns(), option);
+			if (!gid_valid(gid)) {
+				pr_err("Invalid gid %d, "
+				       "using default\n", option);
+				break;
+			}
+			opts->gid = gid;
+			opts->use_gid = 1;
+			break;
+		case Opt_charset:
+			kfree(opts->iocharset);
+			opts->iocharset = match_strdup(&args[0]);
+			if (!opts->iocharset) {
+				pr_err("allocation failure for "
+				       "iocharset string\n");
+				return 0;
+			}
+			break;
+		case Opt_debug:
+			opts->debug = 1;
+			break;
+		default:
+			pr_err("Unrecognized mount option \"%s\" "
+			       "or missing value\n", p);
+			return 0;
+		}
+	}
+	return 1;
+}
+
+static int befs_show_options(struct seq_file *m, struct dentry *root)
+{
+	struct befs_sb_info *befs_sb = BEFS_SB(root->d_sb);
+	struct befs_mount_options *opts = &befs_sb->mount_opts;
+
+	if (!uid_eq(opts->uid, GLOBAL_ROOT_UID))
+		seq_printf(m, ",uid=%u",
+			   from_kuid_munged(&init_user_ns, opts->uid));
+	if (!gid_eq(opts->gid, GLOBAL_ROOT_GID))
+		seq_printf(m, ",gid=%u",
+			   from_kgid_munged(&init_user_ns, opts->gid));
+	if (opts->iocharset)
+		seq_printf(m, ",charset=%s", opts->iocharset);
+	if (opts->debug)
+		seq_puts(m, ",debug");
+	return 0;
+}
+
+/* This function has the responsibiltiy of getting the
+ * filesystem ready for unmounting.
+ * Basically, we free everything that we allocated in
+ * befs_read_inode
+ */
+static void
+befs_put_super(struct super_block *sb)
+{
+	kfree(BEFS_SB(sb)->mount_opts.iocharset);
+	BEFS_SB(sb)->mount_opts.iocharset = NULL;
+	unload_nls(BEFS_SB(sb)->nls);
+	kfree(sb->s_fs_info);
+	sb->s_fs_info = NULL;
+}
+
+/* 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 int
+befs_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct buffer_head *bh;
+	struct befs_sb_info *befs_sb;
+	befs_super_block *disk_sb;
+	struct inode *root;
+	long ret = -EINVAL;
+	const unsigned long sb_block = 0;
+	const off_t x86_sb_off = 512;
+	int blocksize;
+
+	sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL);
+	if (sb->s_fs_info == NULL)
+		goto unacquire_none;
+
+	befs_sb = BEFS_SB(sb);
+
+	if (!parse_options((char *) data, &befs_sb->mount_opts)) {
+		if (!silent)
+			befs_error(sb, "cannot parse mount options");
+		goto unacquire_priv_sbp;
+	}
+
+	befs_debug(sb, "---> %s", __func__);
+
+	if (!sb_rdonly(sb)) {
+		befs_warning(sb,
+			     "No write support. Marking filesystem read-only");
+		sb->s_flags |= SB_RDONLY;
+	}
+
+	/*
+	 * 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 logical block size for the device. But we also need to read at
+	 * least 1k to get the second 512 bytes of the volume.
+	 */
+	blocksize = sb_min_blocksize(sb, 1024);
+	if (!blocksize) {
+		if (!silent)
+			befs_error(sb, "unable to set blocksize");
+		goto unacquire_priv_sbp;
+	}
+
+	bh = sb_bread(sb, sb_block);
+	if (!bh) {
+		if (!silent)
+			befs_error(sb, "unable to read superblock");
+		goto unacquire_priv_sbp;
+	}
+
+	/* account for offset of super block on x86 */
+	disk_sb = (befs_super_block *) bh->b_data;
+	if ((disk_sb->magic1 == BEFS_SUPER_MAGIC1_LE) ||
+	    (disk_sb->magic1 == BEFS_SUPER_MAGIC1_BE)) {
+		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) ||
+	    (befs_check_sb(sb) != BEFS_OK))
+		goto unacquire_bh;
+
+	befs_dump_super_block(sb, disk_sb);
+
+	brelse(bh);
+
+	if (befs_sb->num_blocks > ~((sector_t)0)) {
+		if (!silent)
+			befs_error(sb, "blocks count: %llu is larger than the host can use",
+					befs_sb->num_blocks);
+		goto unacquire_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;
+	/* Set real blocksize of fs */
+	sb_set_blocksize(sb, (ulong) befs_sb->block_size);
+	sb->s_op = &befs_sops;
+	sb->s_export_op = &befs_export_operations;
+	sb->s_time_min = 0;
+	sb->s_time_max = 0xffffffffffffll;
+	root = befs_iget(sb, iaddr2blockno(sb, &(befs_sb->root_dir)));
+	if (IS_ERR(root)) {
+		ret = PTR_ERR(root);
+		goto unacquire_priv_sbp;
+	}
+	sb->s_root = d_make_root(root);
+	if (!sb->s_root) {
+		if (!silent)
+			befs_error(sb, "get root inode failed");
+		goto unacquire_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"
+					" loading default nls",
+					befs_sb->mount_opts.iocharset);
+			befs_sb->nls = load_nls_default();
+		}
+	/* load default nls if none is specified  in mount options */
+	} else {
+		befs_debug(sb, "Loading default nls");
+		befs_sb->nls = load_nls_default();
+	}
+
+	return 0;
+
+unacquire_bh:
+	brelse(bh);
+
+unacquire_priv_sbp:
+	kfree(befs_sb->mount_opts.iocharset);
+	kfree(sb->s_fs_info);
+	sb->s_fs_info = NULL;
+
+unacquire_none:
+	return ret;
+}
+
+static int
+befs_remount(struct super_block *sb, int *flags, char *data)
+{
+	sync_filesystem(sb);
+	if (!(*flags & SB_RDONLY))
+		return -EINVAL;
+	return 0;
+}
+
+static int
+befs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct super_block *sb = dentry->d_sb;
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
+
+	befs_debug(sb, "---> %s", __func__);
+
+	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_fsid = u64_to_fsid(id);
+	buf->f_namelen = BEFS_NAME_LEN;
+
+	befs_debug(sb, "<--- %s", __func__);
+
+	return 0;
+}
+
+static struct dentry *
+befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name,
+	    void *data)
+{
+	return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super);
+}
+
+static struct file_system_type befs_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "befs",
+	.mount		= befs_mount,
+	.kill_sb	= kill_block_super,
+	.fs_flags	= FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("befs");
+
+static int __init
+init_befs_fs(void)
+{
+	int err;
+
+	pr_info("version: %s\n", BEFS_VERSION);
+
+	err = befs_init_inodecache();
+	if (err)
+		goto unacquire_none;
+
+	err = register_filesystem(&befs_fs_type);
+	if (err)
+		goto unacquire_inodecache;
+
+	return 0;
+
+unacquire_inodecache:
+	befs_destroy_inodecache();
+
+unacquire_none:
+	return err;
+}
+
+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)