path: root/fs/befs/linuxvfs.c

/*
 * linux/fs/befs/linuxvfs.c
 *
 * Copyright (C) 2001 Will Dyson <will_dyson@pobox.com
 *
 */

#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 "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 *, void *, filldir_t);
static int befs_get_block(struct inode *, sector_t, struct buffer_head *, int);
static int befs_readpage(struct file *file, struct page *page);
static sector_t befs_bmap(struct address_space *mapping, sector_t block);
static struct dentry *befs_lookup(struct inode *, struct dentry *, struct nameidata *);
static struct inode *befs_iget(struct super_block *, unsigned long);
static struct inode *befs_alloc_inode(struct super_block *sb);
static void befs_destroy_inode(struct inode *inode);
static int befs_init_inodecache(void);
static void befs_destroy_inodecache(void);
static void *befs_follow_link(struct dentry *, struct nameidata *);
static void befs_put_link(struct dentry *, struct nameidata *, void *);
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 parse_options(char *, befs_mount_options *);

static const struct super_operations befs_sops = {
	.alloc_inode	= befs_alloc_inode,	/* allocate a new inode */
	.destroy_inode	= befs_destroy_inode, /* deallocate an inode */
	.put_super	= befs_put_super,	/* uninit super */
	.statfs		= befs_statfs,	/* statfs */
	.remount_fs	= befs_remount,
	.show_options	= generic_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,
	.readdir	= 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 = {
	.readpage	= befs_readpage,
	.bmap		= befs_bmap,
};

static const struct inode_operations befs_symlink_inode_operations = {
	.readlink	= generic_readlink,
	.follow_link	= befs_follow_link,
	.put_link	= befs_put_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 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.
 *
 * -WD 10-26-01
 */

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 = 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