path: root/fs/f2fs/f2fs.h

/*
 * fs/f2fs/f2fs.h
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *             http://www.samsung.com/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef _LINUX_F2FS_H
#define _LINUX_F2FS_H

#include <linux/types.h>
#include <linux/page-flags.h>
#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <linux/crc32.h>
#include <linux/magic.h>

/*
 * For mount options
 */
#define F2FS_MOUNT_BG_GC		0x00000001
#define F2FS_MOUNT_DISABLE_ROLL_FORWARD	0x00000002
#define F2FS_MOUNT_DISCARD		0x00000004
#define F2FS_MOUNT_NOHEAP		0x00000008
#define F2FS_MOUNT_XATTR_USER		0x00000010
#define F2FS_MOUNT_POSIX_ACL		0x00000020
#define F2FS_MOUNT_DISABLE_EXT_IDENTIFY	0x00000040

#define clear_opt(sbi, option)	(sbi->mount_opt.opt &= ~F2FS_MOUNT_##option)
#define set_opt(sbi, option)	(sbi->mount_opt.opt |= F2FS_MOUNT_##option)
#define test_opt(sbi, option)	(sbi->mount_opt.opt & F2FS_MOUNT_##option)

#define ver_after(a, b)	(typecheck(unsigned long long, a) &&		\
		typecheck(unsigned long long, b) &&			\
		((long long)((a) - (b)) > 0))

typedef u64 block_t;
typedef u32 nid_t;

struct f2fs_mount_info {
	unsigned int	opt;
};

static inline __u32 f2fs_crc32(void *buff, size_t len)
{
	return crc32_le(F2FS_SUPER_MAGIC, buff, len);
}

static inline bool f2fs_crc_valid(__u32 blk_crc, void *buff, size_t buff_size)
{
	return f2fs_crc32(buff, buff_size) == blk_crc;
}

/*
 * For checkpoint manager
 */
enum {
	NAT_BITMAP,
	SIT_BITMAP
};

/* for the list of orphan inodes */
struct orphan_inode_entry {
	struct list_head list;	/* list head */
	nid_t ino;		/* inode number */
};

/* for the list of directory inodes */
struct dir_inode_entry {
	struct list_head list;	/* list head */
	struct inode *inode;	/* vfs inode pointer */
};

/* for the list of fsync inodes, used only during recovery */
struct fsync_inode_entry {
	struct list_head list;	/* list head */
	struct inode *inode;	/* vfs inode pointer */
	block_t blkaddr;	/* block address locating the last inode */
};

#define nats_in_cursum(sum)		(le16_to_cpu(sum->n_nats))
#define sits_in_cursum(sum)		(le16_to_cpu(sum->n_sits))

#define nat_in_journal(sum, i)		(sum->nat_j.entries[i].ne)
#define nid_in_journal(sum, i)		(sum->nat_j.entries[i].nid)
#define sit_in_journal(sum, i)		(sum->sit_j.entries[i].se)
#define segno_in_journal(sum, i)	(sum->sit_j.entries[i].segno)

static inline int update_nats_in_cursum(struct f2fs_summary_block *rs, int i)
{
	int before = nats_in_cursum(rs);
	rs->n_nats = cpu_to_le16(before + i);
	return before;
}

static inline int update_sits_in_cursum(struct f2fs_summary_block *rs, int i)
{
	int before = sits_in_cursum(rs);
	rs->n_sits = cpu_to_le16(before + i);
	return before;
}

/*
 * For INODE and NODE manager
 */
#define XATTR_NODE_OFFSET	(-1)	/*
					 * store xattrs to one node block per
					 * file keeping -1 as its node offset to
					 * distinguish from index node blocks.
					 */
#define RDONLY_NODE		1	/*
					 * specify a read-only mode when getting
					 * a node block. 0 is read-write mode.
					 * used by get_dnode_of_data().
					 */
#define F2FS_LINK_MAX		32000	/* maximum link count per file */

/* for in-memory extent cache entry */
struct extent_info {
	rwlock_t ext_lock;	/* rwlock for consistency */
	unsigned int fofs;	/* start offset in a file */
	u32 blk_addr;		/* start block address of the extent */
	unsigned int len;	/* lenth of the extent */
};

/*
 * i_advise uses FADVISE_XXX_BIT. We can add additional hints later.
 */
#define FADVISE_COLD_BIT	0x01

struct f2fs_inode_info {
	struct inode vfs_inode;		/* serve a vfs inode */
	unsigned long i_flags;		/* keep an inode flags for ioctl */
	unsigned char i_advise;		/* use to give file attribute hints */
	unsigned int i_current_depth;	/* use only in directory structure */
	unsigned int i_pino;		/* parent inode number */
	umode_t i_acl_mode;		/* keep file acl mode temporarily */

	/* Use below internally in f2fs*/
	unsigned long flags;		/* use to pass per-file flags */
	unsigned long long data_version;/* lastes version of data for fsync */
	atomic_t dirty_dents;		/* # of dirty dentry pages */
	f2fs_hash_t chash;		/* hash value of given file name */
	unsigned int clevel;		/* maximum level of given file name */
	nid_t i_xattr_nid;		/* node id that contains xattrs */
	struct extent_info ext;		/* in-memory extent cache entry */
};

static inline void get_extent_info(struct extent_info *ext,
					struct f2fs_extent i_ext)
{
	write_lock(&ext->ext_lock);
	ext->fofs = le32_to_cpu(i_ext.fofs);
	ext->blk_addr = le32_to_cpu(i_ext.blk_addr);
	ext->len = le32_to_cpu(i_ext.len);
	write_unlock(&ext->ext_lock);
}

static inline void set_raw_extent(struct extent_info *ext,
					struct f2fs_extent *i_ext)
{
	read_lock(&ext->ext_lock);
	i_ext->fofs = cpu_to_le32(ext->fofs);
	<