// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/fs/befs/linuxvfs.c
*
* Copyright (C) 2001 Will Dyson <[email protected]
*
*/
#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 = {
.encode_fh = generic_encode_ino32_fh,
.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_set_mtime(inode,
fs64_to_cpu(sb, raw_inode->last_modified_time) >> 16,
0);/* lower 16 bits are not a time */
inode_set_ctime_to_ts(inode, inode_get_mtime(inode));
inode_set_atime_to_ts(inode, inode_get_mtime(inode));
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_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);
int err = -EIO;
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';
err = 0;
fail:
folio_end_read(folio, err == 0);
return err;
}
/*
* 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);
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)
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