misc/e4defrag.c

/*
 * e4defrag.c - ext4 filesystem defragmenter
 *
 * Copyright (C) 2009 NEC Software Tohoku, Ltd.
 *
 * Author: Akira Fujita	<a-fujita@rs.jp.nec.com>
 *         Takashi Sato	<t-sato@yk.jp.nec.com>
 */

#ifndef _LARGEFILE_SOURCE
#define _LARGEFILE_SOURCE
#endif

#ifndef _LARGEFILE64_SOURCE
#define _LARGEFILE64_SOURCE
#endif

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

#include <ctype.h>
#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <ftw.h>
#include <limits.h>
#include <mntent.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ext2fs/ext2_types.h>
#include <ext2fs/ext2fs.h>
#include <linux/fs.h>
#include <sys/ioctl.h>
#include <ext2fs/fiemap.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <sys/syscall.h>
#include <sys/vfs.h>

/* A relatively new ioctl interface ... */
#ifndef EXT4_IOC_MOVE_EXT
#define EXT4_IOC_MOVE_EXT      _IOWR('f', 15, struct move_extent)
#endif

/* Macro functions */
#define PRINT_ERR_MSG(msg)	fprintf(stderr, "%s\n", (msg))
#define IN_FTW_PRINT_ERR_MSG(msg)	\
	fprintf(stderr, "\t%s\t\t[ NG ]\n", (msg))
#define PRINT_FILE_NAME(file)	fprintf(stderr, " \"%s\"\n", (file))
#define PRINT_ERR_MSG_WITH_ERRNO(msg)	\
	fprintf(stderr, "\t%s:%s\t[ NG ]\n", (msg), strerror(errno))
#define STATISTIC_ERR_MSG(msg)	\
	fprintf(stderr, "\t%s\n", (msg))
#define STATISTIC_ERR_MSG_WITH_ERRNO(msg)	\
	fprintf(stderr, "\t%s:%s\n", (msg), strerror(errno))
#define min(x, y) (((x) > (y)) ? (y) : (x))
#define SECTOR_TO_BLOCK(sectors, blocksize) \
	((sectors) / ((blocksize) >> 9))
#define CALC_SCORE(ratio) \
	((ratio) > 10 ? (80 + 20 * (ratio) / 100) : (8 * (ratio)))
/* Wrap up the free function */
#define FREE(tmp)				\
	do {					\
		if ((tmp) != NULL)		\
			free(tmp);		\
	} while (0)				\
/* Insert list2 after list1 */
#define insert(list1, list2)			\
	do {					\
		list2->next = list1->next;	\
		list1->next->prev = list2;	\
		list2->prev = list1;		\
		list1->next = list2;		\
	} while (0)

/* To delete unused warning */
#ifdef __GNUC__
#define EXT2FS_ATTR(x) __attribute__(x)
#else
#define EXT2FS_ATTR(x)
#endif

/* The mode of defrag */
#define DETAIL			0x01
#define STATISTIC		0x02

#define DEVNAME			0
#define DIRNAME			1
#define FILENAME		2

#define FTW_OPEN_FD		2000

#define FS_EXT4			"ext4"
#define ROOT_UID		0

#define BOUND_SCORE		55
#define SHOW_FRAG_FILES	5

/* Magic number for ext4 */
#define EXT4_SUPER_MAGIC	0xEF53

/* Definition of flex_bg */
#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200

/* The following macro is used for ioctl FS_IOC_FIEMAP
 * EXTENT_MAX_COUNT:	the maximum number of extents for exchanging between
 *			kernel-space and user-space per ioctl
 */
#define EXTENT_MAX_COUNT	512

/* The following macros are error message */
#define MSG_USAGE		\
"Usage	: e4defrag [-v] file...| directory...| device...\n\
	: e4defrag  -c  file...| directory...| device...\n"

#define NGMSG_EXT4		"Filesystem is not ext4 filesystem"
#define NGMSG_FILE_EXTENT	"Failed to get file extents"
#define NGMSG_FILE_INFO		"Failed to get file information"
#define NGMSG_FILE_OPEN		"Failed to open"
#define NGMSG_FILE_UNREG	"File is not regular file"
#define NGMSG_LOST_FOUND	"Can not process \"lost+found\""

/* Data type for filesystem-wide blocks number */
typedef unsigned long long ext4_fsblk_t;

struct fiemap_extent_data {
	__u64 len;			/* blocks count */
	__u64 logical;		/* start logical block number */
	ext4_fsblk_t physical;		/* start physical block number */
};

struct fiemap_extent_list {
	struct fiemap_extent_list *prev;
	struct fiemap_extent_list *next;
	struct fiemap_extent_data data;	/* extent belong to file */
};

struct fiemap_extent_group {
	struct fiemap_extent_group *prev;
	struct fiemap_extent_group *next;
	__u64 len;	/* length of this continuous region */
	struct fiemap_extent_list *start;	/* start ext */
	struct fiemap_extent_list *end;		/* end ext */
};

struct move_extent {
	__s32 reserved;	/* original file descriptor */
	__u32 donor_fd;	/* donor file descriptor */
	__u64 orig_start;	/* logical start offset in block for orig */
	__u64 donor_start;	/* logical start offset in block for donor */
	__u64 len;	/* block length to be moved */
	__u64 moved_len;	/* moved block length */
};

struct frag_statistic_ino {
	int now_count;	/* the file's extents count of before defrag */
	int best_count; /* the best file's extents count */
	float ratio;	/* the ratio of fragmentation */
	char msg_buffer[PATH_MAX + 1];	/* pathname of the file */
};

typedef __u16 __le16;
typedef __u32 __le32;
typedef __u64 __le64;

/*
 * Structure of the super block
 */
struct ext4_super_block {
/*00*/	__le32	s_inodes_count;		/* Inodes count */
	__le32	s_blocks_count_lo;	/* Blocks count */
	__le32	s_r_blocks_count_lo;	/* Reserved blocks count */
	__le32	s_free_blocks_count_lo;	/* Free blocks count */
/*10*/	__le32	s_free_inodes_count;	/* Free inodes count */
	__le32	s_first_data_block;	/* First Data Block */
	__le32	s_log_block_size;	/* Block size */
	__le32	s_obso_log_frag_size;	/* Obsoleted fragment size */
/*20*/	__le32	s_blocks_per_group;	/* # Blocks per group */
	__le32	s_obso_frags_per_group;	/* Obsoleted fragments per group */
	__le32	s_inodes_per_group;	/* # Inodes per group */
	__le32	s_mtime;		/* Mount time */
/*30*/	__le32	s_wtime;		/* Write time */
	__le16	s_mnt_count;		/* Mount count */
	__le16	s_max_mnt_count;	/* Maximal mount count */
	__le16	s_magic;		/* Magic signature */
	__le16	s_state;		/* File system state */
	__le16	s_errors;		/* Behaviour when detecting errors */
	__le16	s_minor_rev_level;	/* minor revision level */
/*40*/	__le32	s_lastcheck;		/* time of last check */
	__le32	s_checkinterval;	/* max. time between checks */
	__le32	s_creator_os;		/* OS */
	__le32	s_rev_level;		/* Revision level */
/*50*/	__le16	s_def_resuid;		/* Default uid for reserved blocks */
	__le16	s_def_resgid;		/* Default gid for reserved blocks */
	/*
	 * These fields are for EXT4_DYNAMIC_REV superblocks only.
	 *
	 * Note: the difference between the compatible feature set and
	 * the incompatible feature set is that if there is a bit set
	 * in the incompatible feature set that the kernel doesn't
	 * know about, it should refuse to mount the filesystem.
	 *
	 * e2fsck's requirements are more strict; if it doesn't know
	 * about a feature in either the compatible or incompatible
	 * feature set, it must abort and not try to meddle with
	 * things it doesn't understand...
	 */
	__le32	s_first_ino;		/* First non-reserved inode */
	__le16  s_inode_size;		/* size of inode structure */
	__le16	s_block_group_nr;	/* block group # of this superblock */
	__le32	s_feature_compat;	/* compatible feature set */
/*60*/	__le32	s_feature_incompat;	/* incompatible feature set */
	__le32	s_feature_ro_compat;	/* readonly-compatible feature set */
/*68*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
/*78*/	char	s_volume_name[16];	/* volume name */
/*88*/	char	s_last_mounted[64];	/* directory where last mounted */
/*C8*/	__le32	s_algorithm_usage_bitmap; /* For compression */
	/*
	 * Performance hints.  Directory preallocation should only
	 * happen if the EXT4_FEATURE_COMPAT_DIR_PREALLOC flag is on.
	 */
	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/
	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */
	__le16	s_reserved_gdt_blocks;	/* Per group desc for online growth */
	/*
	 * Journaling support valid if EXT4_FEATURE_COMPAT_HAS_JOURNAL set.
	 */
/*D0*/	__u8	s_journal_uuid[16];	/* uuid of journal superblock */
/*E0*/	__le32	s_journal_inum;		/* inode number of journal file */
	__le32	s_journal_dev;		/* device number of journal file */
	__le32	s_last_orphan;		/* start of list of inodes to delete */
	__le32	s_hash_seed[4];		/* HTREE hash seed */
	__u8	s_def_hash_version;	/* Default hash version to use */
	__u8	s_reserved_char_pad;
	__le16  s_desc_size;		/* size of group descriptor */
/*100*/	__le32	s_default_mount_opts;
	__le32	s_first_meta_bg;	/* First metablock block group */
	__le32	s_mkfs_time;		/* When the filesystem was created */
	__le32	s_jnl_blocks[17];	/* Backup of the journal inode */
	/* 64bit support valid if EXT4_FEATURE_COMPAT_64BIT */
/*150*/	__le32	s_blocks_count_hi;	/* Blocks count */
	__le32	s_r_blocks_count_hi;	/* Reserved blocks count */
	__le32	s_free_blocks_count_hi;	/* Free blocks count */
	__le16	s_min_extra_isize;	/* All inodes have at least # bytes */
	__le16	s_want_extra_isize; 	/* New inodes should reserve # bytes */
	__le32	s_flags;		/* Miscellaneous flags */
	__le16  s_raid_stride;		/* RAID stride */
	__le16  s_mmp_interval;         /* # seconds to wait in MMP checking */
	__le64  s_mmp_block;            /* Block for multi-mount protection */
	__le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
	__u8	s_log_groups_per_flex;  /* FLEX_BG group size */
	__u8	s_reserved_char_pad2;
	__le16  s_reserved_pad;
	__u32   s_reserved[162];        /* Padding to the end of the block */
};

char	lost_found_dir[PATH_MAX + 1];
int	block_size;
int	extents_before_defrag;
int	extents_after_defrag;
int	mode_flag;
unsigned int	current_uid;
unsigned int	defraged_file_count;
unsigned int	frag_files_before_defrag;
unsigned int	frag_files_after_defrag;
unsigned int	regular_count;
unsigned int	succeed_cnt;
unsigned int	total_count;
__u8 log_groups_per_flex;
__le32 blocks_per_group;
__le32 feature_incompat;
ext4_fsblk_t	files_block_count;
struct frag_statistic_ino	frag_rank[SHOW_FRAG_FILES];


/* Local definitions of some syscalls glibc may not yet have */

#ifndef HAVE_POSIX_FADVISE
#warning Using locally defined posix_fadvise interface.

#ifndef __NR_fadvise64_64
#error Your kernel headers dont define __NR_fadvise64_64
#endif

/*
 * fadvise() -		Give advice about file access.
 *
 * @fd:			defrag target file's descriptor.
 * @offset:		file offset.
 * @len:		area length.
 * @advise:		process flag.
 */
static int posix_fadvise(int fd, loff_t offset, size_t len, int advise)
{
	return syscall(__NR_fadvise64_64, fd, offset, len, advise);
}
#endif /* ! HAVE_FADVISE64_64 */

#ifndef HAVE_SYNC_FILE_RANGE
#warning Using locally defined sync_file_range interface.

#ifndef __NR_sync_file_range
#ifndef __NR_sync_file_range2 /* ppc */
#error Your kernel headers dont define __NR_sync_file_range
#endif
#endif

/*
 * sync_file_range() -	Sync file region.
 *
 * @fd:			defrag target file's descriptor.
 * @offset:		file offset.
 * @length:		area length.
 * @flag:		process flag.
 */
int sync_file_range(int fd, loff_t offset, loff_t length, unsigned int flag)
{
#ifdef __NR_sync_file_range
	return syscall(__NR_sync_file_range, fd, offset, length, flag);
#else
	return syscall(__NR_sync_file_range2, fd, flag, offset, length);
#endif
}
#endif /* ! HAVE_SYNC_FILE_RANGE */

#ifndef HAVE_FALLOCATE
#warning Using locally defined fallocate syscall interface.

#ifndef __NR_fallocate
#error Your kernel headers dont define __NR_fallocate
#endif

/*
 * fallocate() -	Manipulate file space.
 *
 * @fd:			defrag target file's descriptor.
 * @mode:		process flag.
 * @offset:		file offset.
 * @len:		file size.
 */
static int fallocate(int fd, int mode, loff_t offset, loff_t len)
{
	return syscall(__NR_fallocate, fd, mode, offset, len);
}
#endif /* ! HAVE_FALLOCATE */

/*
 * get_mount_point() -	Get device's mount point.
 *
 * @devname:		the device's name.
 * @mount_point:	the mount point.
 * @dir_path_len:	the length of directory.
 */
static int get_mount_point(const char *devname, char *mount_point,
							int dir_path_len)
{
	/* Refer to /etc/mtab */
	const char	*mtab = MOUNTED;
	FILE	*fp = NULL;
	struct mntent	*mnt = NULL;

	fp = setmntent(mtab, "r");
	if (fp == NULL) {
		perror("Couldn't access /etc/mtab");
		return -1;
	}

	while ((mnt = getmntent(fp)) != NULL) {
		if (strcmp(devname, mnt->mnt_fsname) != 0)
			continue;

		endmntent(fp);
		if (strcmp(mnt->mnt_type, FS_EXT4) == 0) {
			strncpy(mount_point, mnt->mnt_dir,
				dir_path_len);
			return 0;
		}
		PRINT_ERR_MSG(NGMSG_EXT4);
		return -1;
	}
	endmntent(fp);
	PRINT_ERR_MSG("Filesystem is not mounted");
	return -1;
}

/*
 * is_ext4() -		Whether on an ext4 filesystem.
 *
 * @file:		the file's name.
 */
static int is_ext4(const char *file)
{
	int 	maxlen = 0;
	int	len, ret;
	FILE	*fp = NULL;
	char	*mnt_type = NULL;
	/* Refer to /etc/mtab */
	const char	*mtab = MOUNTED;
	char	file_path[PATH_MAX + 1];
	struct mntent	*mnt = NULL;
	struct statfs64	fsbuf;

	/* Get full path */
	if (realpath(file, file_path) == NULL) {
		perror("Couldn't get full path");
		PRINT_FILE_NAME(file);
		return -1;
	}

	if (statfs64(file_path, &fsbuf) < 0) {
		perror("Failed to get filesystem information");
		PRINT_FILE_NAME(file);
		return -1;
	}

	if (fsbuf.f_type != EXT4_SUPER_MAGIC) {
		PRINT_ERR_MSG(NGMSG_EXT4);
		return -1;
	}

	fp = setmntent(mtab, "r");
	if (fp == NULL) {
		perror("Couldn't access /etc/mtab");
		return -1;
	}

	while ((mnt = getmntent(fp)) != NULL) {
		if (mnt->mnt_fsname[0] != '/')
			continue;
		len = strlen(mnt->mnt_dir);
		ret = memcmp(file_path, mnt->mnt_dir, len);
		if (ret != 0)
			continue;

		if (maxlen >= len)
			continue;

		maxlen = len;

		mnt_type = realloc(mnt_type, strlen(mnt->mnt_type) + 1);
		if (mnt_type == NULL) {
			endmntent(fp);
			return -1;
		}
		memset(mnt_type, 0, strlen(mnt->mnt_type) + 1);
		strncpy(mnt_type, mnt->mnt_type, strlen(mnt->mnt_type));
		strncpy(lost_found_dir, mnt->mnt_dir, PATH_MAX);
	}

	endmntent(fp);
	if (strcmp(mnt_type, FS_EXT4) == 0) {
		FREE(mnt_type);
		return 0;
	} else {
		FREE(mnt_type);
		PRINT_ERR_MSG(NGMSG_EXT4);
		return -1;
	}
}

/*
 * calc_entry_counts() -	Calculate file counts.
 *
 * @file:		file name.
 * @buf:		file info.
 * @flag:		file type.
 * @ftwbuf:		the pointer of a struct FTW.
 */
static int calc_entry_counts(const char *file EXT2FS_ATTR((unused)),
		const struct stat64 *buf, int flag EXT2FS_ATTR((unused)),
		struct FTW *ftwbuf EXT2FS_ATTR((unused)))
{
	if (S_ISREG(buf->st_mode))
		regular_count++;

	total_count++;

	return 0;
}

/*
 * page_in_core() -	Get information on whether pages are in core.
 *
 * @fd:			defrag target file's descriptor.
 * @defrag_data:	data used for defrag.
 * @vec:		page state array.
 * @page_num:		page number.
 */
static int page_in_core(int fd, struct move_extent defrag_data,
			unsigned char **vec, unsigned int *page_num)
{
	long	pagesize = sysconf(_SC_PAGESIZE);
	void	*page = NULL;
	loff_t	offset, end_offset, length;

	if (vec == NULL || *vec != NULL)
		return -1;

	/* In mmap, offset should be a multiple of the page size */
	offset = (loff_t)defrag_data.orig_start * block_size;
	length = (loff_t)defrag_data.len * block_size;
	end_offset = offset + length;
	/* Round the offset down to the nearest multiple of pagesize */
	offset = (offset / pagesize) * pagesize;
	length = end_offset - offset;

	page = mmap(NULL, length, PROT_READ, MAP_SHARED, fd, offset);
	if (page == MAP_FAILED)
		return -1;

	*page_num = 0;
	*page_num = (length + pagesize - 1) / pagesize;
	*vec = (unsigned char *)calloc(*page_num, 1);
	if (*vec == NULL)
		return -1;

	/* Get information on whether pages are in core */
	if (mincore(page, (size_t)length, *vec) == -1 ||
		munmap(page, length) == -1) {
		FREE(*vec);
		return -1;
	}

	return 0;
}

/*
 * defrag_fadvise() -	Predeclare an access pattern for file data.
 *
 * @fd:			defrag target file's descriptor.
 * @defrag_data:	data used for defrag.
 * @vec:		page state array.
 * @page_num:		page number.
 */
static int defrag_fadvise(int fd, struct move_extent defrag_data,
		   unsigned char *vec, unsigned int page_num)
{
	int	flag = 1;
	long	pagesize = sysconf(_SC_PAGESIZE);
	int	fadvise_flag = POSIX_FADV_DONTNEED;
	int	sync_flag = SYNC_FILE_RANGE_WAIT_BEFORE |
			    SYNC_FILE_RANGE_WRITE |
			    SYNC_FILE_RANGE_WAIT_AFTER;
	unsigned int	i;
	loff_t	offset;

	offset = (loff_t)defrag_data.orig_start * block_size;
	offset = (offset / pagesize) * pagesize;

	/* Sync file for fadvise process */
	if (sync_file_range(fd, offset,
		(loff_t)pagesize * page_num, sync_flag) < 0)
		return -1;

	/* Try to release buffer cache which this process used,
	 * then other process can use the released buffer
	 */
	for (i = 0; i < page_num; i++) {
		if ((vec[i] & 0x1) == 0) {
			offset += pagesize;
			continue;
		}
		if (posix_fadvise(fd, offset, pagesize, fadvise_flag) < 0) {
			if ((mode_flag & DETAIL) && flag) {
				perror("\tFailed to fadvise");
				flag = 0;
			}
		}
		offset += pagesize;
	}

	return 0;
}

/*
 * check_free_size() -	Check if there's enough disk space.
 *
 * @fd:			defrag target file's descriptor.
 * @file:		file name.
 * @buf:		the pointer of the struct stat64.
 */
static int check_free_size(int fd, const char *file, const struct stat64 *buf)
{
	ext4_fsblk_t	blk_count;
	ext4_fsblk_t	free_blk_count;
	struct statfs64	fsbuf;

	if (fstatfs64(fd, &fsbuf) < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(
				"Failed to get filesystem information");
		}
		return -1;
	}

	/* Target file size measured by filesystem IO blocksize */
	blk_count = SECTOR_TO_BLOCK(buf->st_blocks, fsbuf.f_bsize);

	/* Compute free space for root and normal user separately */
	if (current_uid == ROOT_UID)
		free_blk_count = fsbuf.f_bfree;
	else
		free_blk_count = fsbuf.f_bavail;

	if (free_blk_count >= blk_count)
		return 0;

	return -ENOSPC;
}

/*
 * file_frag_count() -	Get file fragment count.
 *
 * @fd:			defrag target file's descriptor.
 */
static int file_frag_count(int fd)
{
	int	ret;
	struct fiemap	fiemap_buf;

	/* When fm_extent_count is 0,
	 * ioctl just get file fragment count.
	 */
	memset(&fiemap_buf, 0, sizeof(struct fiemap));
	fiemap_buf.fm_start = 0;
	fiemap_buf.fm_length = FIEMAP_MAX_OFFSET;
	fiemap_buf.fm_flags |= FIEMAP_FLAG_SYNC;

	ret = ioctl(fd, FS_IOC_FIEMAP, &fiemap_buf);
	if (ret < 0)
		return ret;

	return fiemap_buf.fm_mapped_extents;
}

/*
 * file_check() -	Check file's attributes.
 *
 * @fd:			defrag target file's descriptor.
 * @buf:		a pointer of the struct stat64.
 * @file:		the file's name.
 * @extents:		the file's extents.
 */
static int file_check(int fd, const struct stat64 *buf, const char *file,
		int extents)
{
	int	ret;
	struct flock	lock;

	/* Write-lock check is more reliable */
	lock.l_type = F_WRLCK;
	lock.l_start = 0;
	lock.l_whence = SEEK_SET;
	lock.l_len = 0;

	/* Free space */
	ret = check_free_size(fd, file, buf);
	if (ret < 0) {
		if ((mode_flag & DETAIL) && ret == -ENOSPC) {
			printf("\033[79;0H\033[K[%u/%u] \"%s\"\t\t"
				"  extents: %d -> %d\n", defraged_file_count,
				total_count, file, extents, extents);
			IN_FTW_PRINT_ERR_MSG(
			"Defrag size is larger than filesystem's free space");
		}
		return -1;
	}

	/* Access authority */
	if (current_uid != ROOT_UID &&
		buf->st_uid != current_uid) {
		if (mode_flag & DETAIL) {
			printf("\033[79;0H\033[K[%u/%u] \"%s\"\t\t"
				"  extents: %d -> %d\n", defraged_file_count,
				total_count, file, extents, extents);
			IN_FTW_PRINT_ERR_MSG(
				"File is not current user's file"
				" or current user is not root");
		}
		return -1;
	}

	/* Lock status */
	if (fcntl(fd, F_GETLK, &lock) < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(
				"Failed to get lock information");
		}
		return -1;
	} else if (lock.l_type != F_UNLCK) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			IN_FTW_PRINT_ERR_MSG("File has been locked");
		}
		return -1;
	}

	return 0;
}

/*
 * insert_extent_by_logical() -	Sequentially insert extent by logical.
 *
 * @ext_list_head:	the head of logical extent list.
 * @ext:		the extent element which will be inserted.
 */
static int insert_extent_by_logical(struct fiemap_extent_list **ext_list_head,
			struct fiemap_extent_list *ext)
{
	struct fiemap_extent_list	*ext_list_tmp = *ext_list_head;

	if (ext == NULL)
		goto out;

	/* First element */
	if (*ext_list_head == NULL) {
		(*ext_list_head) = ext;
		(*ext_list_head)->prev = *ext_list_head;
		(*ext_list_head)->next = *ext_list_head;
		return 0;
	}

	if (ext->data.logical <= ext_list_tmp->data.logical) {
		/* Insert before head */
		if (ext_list_tmp->data.logical <
			ext->data.logical + ext->data.len)
			/* Overlap */
			goto out;
		/* Adjust head */
		*ext_list_head = ext;
	} else {
		/* Insert into the middle or last of the list */
		do {
			if (ext->data.logical < ext_list_tmp->data.logical)
				break;
			ext_list_tmp = ext_list_tmp->next;
		} while (ext_list_tmp != (*ext_list_head));
		if (ext->data.logical <
		    ext_list_tmp->prev->data.logical +
			ext_list_tmp->prev->data.len)
			/* Overlap */
			goto out;

		if (ext_list_tmp != *ext_list_head &&
		    ext_list_tmp->data.logical <
		    ext->data.logical + ext->data.len)
			/* Overlap */
			goto out;
	}
	ext_list_tmp = ext_list_tmp->prev;
	/* Insert "ext" after "ext_list_tmp" */
	insert(ext_list_tmp, ext);
	return 0;
out:
	errno = EINVAL;
	return -1;
}

/*
 * insert_extent_by_physical() -	Sequentially insert extent by physical.
 *
 * @ext_list_head:	the head of physical extent list.
 * @ext:		the extent element which will be inserted.
 */
static int insert_extent_by_physical(struct fiemap_extent_list **ext_list_head,
			struct fiemap_extent_list *ext)
{
	struct fiemap_extent_list	*ext_list_tmp = *ext_list_head;

	if (ext == NULL)
		goto out;

	/* First element */
	if (*ext_list_head == NULL) {
		(*ext_list_head) = ext;
		(*ext_list_head)->prev = *ext_list_head;
		(*ext_list_head)->next = *ext_list_head;
		return 0;
	}

	if (ext->data.physical <= ext_list_tmp->data.physical) {
		/* Insert before head */
		if (ext_list_tmp->data.physical <
					ext->data.physical + ext->data.len)
			/* Overlap */
			goto out;
		/* Adjust head */
		*ext_list_head = ext;
	} else {
		/* Insert into the middle or last of the list */
		do {
			if (ext->data.physical < ext_list_tmp->data.physical)
				break;
			ext_list_tmp = ext_list_tmp->next;
		} while (ext_list_tmp != (*ext_list_head));
		if (ext->data.physical <
		    ext_list_tmp->prev->data.physical +
				ext_list_tmp->prev->data.len)
			/* Overlap */
			goto out;

		if (ext_list_tmp != *ext_list_head &&
		    ext_list_tmp->data.physical <
				ext->data.physical + ext->data.len)
			/* Overlap */
			goto out;
	}
	ext_list_tmp = ext_list_tmp->prev;
	/* Insert "ext" after "ext_list_tmp" */
	insert(ext_list_tmp, ext);
	return 0;
out:
	errno = EINVAL;
	return -1;
}

/*
 * insert_exts_group() -	Insert a exts_group.
 *
 * @ext_group_head:		the head of a exts_group list.
 * @exts_group:			the exts_group element which will be inserted.
 */
static int insert_exts_group(struct fiemap_extent_group **ext_group_head,
				struct fiemap_extent_group *exts_group)
{
	struct fiemap_extent_group	*ext_group_tmp = NULL;

	if (exts_group == NULL) {
		errno = EINVAL;
		return -1;
	}

	/* Initialize list */
	if (*ext_group_head == NULL) {
		(*ext_group_head) = exts_group;
		(*ext_group_head)->prev = *ext_group_head;
		(*ext_group_head)->next = *ext_group_head;
		return 0;
	}

	ext_group_tmp = (*ext_group_head)->prev;
	insert(ext_group_tmp, exts_group);

	return 0;
}

/*
 * join_extents() -		Find continuous region(exts_group).
 *
 * @ext_list_head:		the head of the extent list.
 * @ext_group_head:		the head of the target exts_group list.
 */
static int join_extents(struct fiemap_extent_list *ext_list_head,
		struct fiemap_extent_group **ext_group_head)
{
	__u64	len = ext_list_head->data.len;
	struct fiemap_extent_list *ext_list_start = ext_list_head;
	struct fiemap_extent_list *ext_list_tmp = ext_list_head->next;

	do {
		struct fiemap_extent_group	*ext_group_tmp = NULL;

		/* This extent and previous extent are not continuous,
		 * so, all previous extents are treated as an extent group.
		 */
		if ((ext_list_tmp->prev->data.logical +
			ext_list_tmp->prev->data.len)
				!= ext_list_tmp->data.logical) {
			ext_group_tmp =
				malloc(sizeof(struct fiemap_extent_group));
			if (ext_group_tmp == NULL)
				return -1;

			memset(ext_group_tmp, 0,
				sizeof(struct fiemap_extent_group));
			ext_group_tmp->len = len;
			ext_group_tmp->start = ext_list_start;
			ext_group_tmp->end = ext_list_tmp->prev;

			if (insert_exts_group(ext_group_head,
				ext_group_tmp) < 0) {
				FREE(ext_group_tmp);
				return -1;
			}
			ext_list_start = ext_list_tmp;
			len = ext_list_tmp->data.len;
			ext_list_tmp = ext_list_tmp->next;
			continue;
		}

		/* This extent and previous extent are continuous,
		 * so, they belong to the same extent group, and we check
		 * if the next extent belongs to the same extent group.
		 */
		len += ext_list_tmp->data.len;
		ext_list_tmp = ext_list_tmp->next;
	} while (ext_list_tmp != ext_list_head->next);

	return 0;
}

/*
 * get_file_extents() -	Get file's extent list.
 *
 * @fd:			defrag target file's descriptor.
 * @ext_list_head:	the head of the extent list.
 */
static int get_file_extents(int fd, struct fiemap_extent_list **ext_list_head)
{
	__u32	i;
	int	ret;
	int	ext_buf_size, fie_buf_size;
	__u64	pos = 0;
	struct fiemap	*fiemap_buf = NULL;
	struct fiemap_extent	*ext_buf = NULL;
	struct fiemap_extent_list	*ext_list = NULL;

	/* Convert units, in bytes.
	 * Be careful : now, physical block number in extent is 48bit,
	 * and the maximum blocksize for ext4 is 4K(12bit),
	 * so there is no overflow, but in future it may be changed.
	 */

	/* Alloc space for fiemap */
	ext_buf_size = EXTENT_MAX_COUNT * sizeof(struct fiemap_extent);
	fie_buf_size = sizeof(struct fiemap) + ext_buf_size;

	fiemap_buf = malloc(fie_buf_size);
	if (fiemap_buf == NULL)
		return -1;

	ext_buf = fiemap_buf->fm_extents;
	memset(fiemap_buf, 0, fie_buf_size);
	fiemap_buf->fm_length = FIEMAP_MAX_OFFSET;
	fiemap_buf->fm_flags |= FIEMAP_FLAG_SYNC;
	fiemap_buf->fm_extent_count = EXTENT_MAX_COUNT;

	do {
		fiemap_buf->fm_start = pos;
		memset(ext_buf, 0, ext_buf_size);
		ret = ioctl(fd, FS_IOC_FIEMAP, fiemap_buf);
		if (ret < 0)
			goto out;
		for (i = 0; i < fiemap_buf->fm_mapped_extents; i++) {
			ext_list = NULL;
			ext_list = malloc(sizeof(struct fiemap_extent_list));
			if (ext_list == NULL)
				goto out;

			ext_list->data.physical = ext_buf[i].fe_physical
						/ block_size;
			ext_list->data.logical = ext_buf[i].fe_logical
						/ block_size;
			ext_list->data.len = ext_buf[i].fe_length
						/ block_size;

			ret = insert_extent_by_physical(
					ext_list_head, ext_list);
			if (ret < 0) {
				FREE(ext_list);
				goto out;
			}
		}
		/* Record file's logical offset this time */
		pos = ext_buf[EXTENT_MAX_COUNT-1].fe_logical +
			ext_buf[EXTENT_MAX_COUNT-1].fe_length;
		/*
		 * If fm_extents array has been filled and
		 * there are extents left, continue to cycle.
		 */
	} while (fiemap_buf->fm_mapped_extents
					== EXTENT_MAX_COUNT &&
		!(ext_buf[EXTENT_MAX_COUNT-1].fe_flags
					& FIEMAP_EXTENT_LAST));

	FREE(fiemap_buf);
	return 0;
out:
	FREE(fiemap_buf);
	return -1;
}

/*
 * get_logical_count() -	Get the file logical extents count.
 *
 * @logical_list_head:	the head of the logical extent list.
 */
static int get_logical_count(struct fiemap_extent_list *logical_list_head)
{
	int ret = 0;
	struct fiemap_extent_list *ext_list_tmp  = logical_list_head;

	do {
		ret++;
		ext_list_tmp = ext_list_tmp->next;
	} while (ext_list_tmp != logical_list_head);

	return ret;
}

/*
 * get_physical_count() -	Get the file physical extents count.
 *
 * @physical_list_head:	the head of the physical extent list.
 */
static int get_physical_count(struct fiemap_extent_list *physical_list_head)
{
	int ret = 0;
	struct fiemap_extent_list *ext_list_tmp = physical_list_head;

	do {
		if ((ext_list_tmp->data.physical + ext_list_tmp->data.len)
				!= ext_list_tmp->next->data.physical) {
			/* This extent and next extent are not continuous. */
			ret++;
		}

		ext_list_tmp = ext_list_tmp->next;
	} while (ext_list_tmp != physical_list_head);

	return ret;
}

/*
 * change_physical_to_logical() -	Change list from physical to logical.
 *
 * @physical_list_head:	the head of physical extent list.
 * @logical_list_head:	the head of logical extent list.
 */
static int change_physical_to_logical(
			struct fiemap_extent_list **physical_list_head,
			struct fiemap_extent_list **logical_list_head)
{
	int ret;
	struct fiemap_extent_list *ext_list_tmp = *physical_list_head;
	struct fiemap_extent_list *ext_list_next = ext_list_tmp->next;

	while (1) {
		if (ext_list_tmp == ext_list_next) {
			ret = insert_extent_by_logical(
				logical_list_head, ext_list_tmp);
			if (ret < 0)
				return -1;

			*physical_list_head = NULL;
			break;
		}

		ext_list_tmp->prev->next = ext_list_tmp->next;
		ext_list_tmp->next->prev = ext_list_tmp->prev;
		*physical_list_head = ext_list_next;

		ret = insert_extent_by_logical(
			logical_list_head, ext_list_tmp);
		if (ret < 0) {
			FREE(ext_list_tmp);
			return -1;
		}
		ext_list_tmp = ext_list_next;
		ext_list_next = ext_list_next->next;
	}

	return 0;
}

/*
 * free_ext() -		Free the extent list.
 *
 * @ext_list_head:	the extent list head of which will be free.
 */
static void free_ext(struct fiemap_extent_list *ext_list_head)
{
	struct fiemap_extent_list	*ext_list_tmp = NULL;

	if (ext_list_head == NULL)
		return;

	while (ext_list_head->next != ext_list_head) {
		ext_list_tmp = ext_list_head;
		ext_list_head->prev->next = ext_list_head->next;
		ext_list_head->next->prev = ext_list_head->prev;
		ext_list_head = ext_list_head->next;
		free(ext_list_tmp);
	}
	free(ext_list_head);
}

/*
 * free_exts_group() -		Free the exts_group.
 *
 * @*ext_group_head:	the exts_group list head which will be free.
 */
static void free_exts_group(struct fiemap_extent_group *ext_group_head)
{
	struct fiemap_extent_group	*ext_group_tmp = NULL;

	if (ext_group_head == NULL)
		return;

	while (ext_group_head->next != ext_group_head) {
		ext_group_tmp = ext_group_head;
		ext_group_head->prev->next = ext_group_head->next;
		ext_group_head->next->prev = ext_group_head->prev;
		ext_group_head = ext_group_head->next;
		free(ext_group_tmp);
	}
	free(ext_group_head);
}

/*
 * get_superblock_info() -	Get superblock info by the file name.
 *
 * @file:		the file's name.
 * @sb:		the pointer of the struct ext4_super_block.
 */
static int get_superblock_info(const char *file, struct ext4_super_block *sb)
{
	/* Refer to /etc/mtab */
	const char	*mtab = MOUNTED;
	FILE	*fp = NULL;

	int	fd = -1;
	int	ret;
	size_t maxlen = 0;
	size_t len;
	char	dev_name[PATH_MAX + 1];
	struct mntent	*mnt = NULL;

	fp = setmntent(mtab, "r");
	if (fp == NULL)
		return -1;

	while ((mnt = getmntent(fp)) != NULL) {
		len = strlen(mnt->mnt_dir);
		ret = memcmp(file, mnt->mnt_dir, len);
		if (ret != 0)
			continue;

		if (len < maxlen)
			continue;

		maxlen = len;

		memset(dev_name, 0, PATH_MAX + 1);
		strncpy(dev_name, mnt->mnt_fsname,
				strnlen(mnt->mnt_fsname, PATH_MAX));
	}

	fd = open64(dev_name, O_RDONLY);
	if (fd < 0) {
		ret = -1;
		goto out;
	}

	/* Set offset to read superblock */
	ret = lseek64(fd, SUPERBLOCK_OFFSET, SEEK_SET);
	if (ret < 0)
		goto out;

	ret = read(fd, sb, sizeof(struct ext4_super_block));
	if (ret < 0)
		goto out;

out:
	if (fd != -1)
		close(fd);
	endmntent(fp);
	return ret;
}

/*
 * get_best_count() -	Get the file best extents count.
 *
 * @block_count:		the file's physical block count.
 */
static int get_best_count(ext4_fsblk_t block_count)
{
	int ret;
	unsigned int flex_bg_num;

	/* Calcuate best extents count */
	if (feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
		flex_bg_num = 1 << log_groups_per_flex;
		ret = ((block_count - 1) /
			((ext4_fsblk_t)blocks_per_group *
				flex_bg_num)) + 1;
	} else
		ret = ((block_count - 1) / blocks_per_group) + 1;

	return ret;
}


/*
 * file_statistic() -	Get statistic info of the file's fragments.
 *
 * @file:		the file's name.
 * @buf:		the pointer of the struct stat64.
 * @flag:		file type.
 * @ftwbuf:		the pointer of a struct FTW.
 */
static int file_statistic(const char *file, const struct stat64 *buf,
			int flag EXT2FS_ATTR((unused)),
			struct FTW *ftwbuf EXT2FS_ATTR((unused)))
{
	int	fd;
	int	ret;
	int	now_ext_count, best_ext_count = 0, physical_ext_count;
	int	i, j;
	float	ratio = 0.0;
	ext4_fsblk_t	blk_count = 0;
	char	msg_buffer[PATH_MAX + 24];
	struct fiemap_extent_list *physical_list_head = NULL;
	struct fiemap_extent_list *logical_list_head = NULL;

	defraged_file_count++;

	if (mode_flag & DETAIL) {
		if (total_count == 1 && regular_count == 1)
			printf("<File>\n");
		else {
			printf("[%u/%u]", defraged_file_count, total_count);
			fflush(stdout);
		}
	}
	if (lost_found_dir[0] != '\0' &&
	    !memcmp(file, lost_found_dir, strnlen(lost_found_dir, PATH_MAX))) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG(NGMSG_LOST_FOUND);
		}
			return 0;
	}

	if (!S_ISREG(buf->st_mode)) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG(NGMSG_FILE_UNREG);
		}
		return 0;
	}

	/* Access authority */
	if (current_uid != ROOT_UID &&
		buf->st_uid != current_uid) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG(
				"File is not current user's file"
				" or current user is not root");
		}
		return 0;
	}

	/* Empty file */
	if (buf->st_size == 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG("File size is 0");
		}
		return 0;
	}

	/* Has no blocks */
	if (buf->st_blocks == 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG("File has no blocks");
		}
		return 0;
	}

	fd = open64(file, O_RDONLY);
	if (fd < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG_WITH_ERRNO(NGMSG_FILE_OPEN);
		}
		return 0;
	}

	/* Get file's physical extents  */
	ret = get_file_extents(fd, &physical_list_head);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG_WITH_ERRNO(NGMSG_FILE_EXTENT);
		}
		goto out;
	}

	/* Get the count of file's continuous physical region */
	physical_ext_count = get_physical_count(physical_list_head);

	/* Change list from physical to logical */
	ret = change_physical_to_logical(&physical_list_head,
							&logical_list_head);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG_WITH_ERRNO(NGMSG_FILE_EXTENT);
		}
		goto out;
	}

	/* Count file fragments before defrag */
	now_ext_count = get_logical_count(logical_list_head);

	if (current_uid == ROOT_UID) {
		/* Calculate fragment ratio  */
		blk_count =
				SECTOR_TO_BLOCK(buf->st_blocks, block_size);

		best_ext_count = get_best_count(blk_count);

		ratio = (float)(physical_ext_count - best_ext_count) * 100 /
							blk_count;

		extents_before_defrag += now_ext_count;
		extents_after_defrag += best_ext_count;
		files_block_count += blk_count;
	}

	if (total_count == 1 && regular_count == 1) {
		/* File only */
		if (mode_flag & DETAIL) {
			int count = 0;
			struct fiemap_extent_list *ext_list_tmp =
						logical_list_head;

			/* Print extents info */
			do {
				count++;
				printf("[ext %d]:\tstart %llu:\tlogical "
						"%llu:\tlen %llu\n", count,
						ext_list_tmp->data.physical,
						ext_list_tmp->data.logical,
						ext_list_tmp->data.len);
				ext_list_tmp = ext_list_tmp->next;
			} while (ext_list_tmp != logical_list_head);

		} else {
			printf("%-40s%10s/%-10s%9s\n",
					"<File>", "now", "best", "ratio");
			if (current_uid == ROOT_UID) {
				if (strlen(file) > 40)
					printf("%s\n%50d/%-10d%8.2f%%\n",
						file, now_ext_count,
						best_ext_count, ratio);
				else
					printf("%-40s%10d/%-10d%8.2f%%\n",
						file, now_ext_count,
						best_ext_count, ratio);
			} else {
				if (strlen(file) > 40)
					printf("%s\n%50d/%-10s%7s\n",
							file, now_ext_count,
							"-", "-");
				else
					printf("%-40s%10d/%-10s%7s\n",
							file, now_ext_count,
							"-", "-");
			}
		}
		succeed_cnt++;
		goto out;
	}

	if (mode_flag & DETAIL) {
		/* Print statistic info */
		sprintf(msg_buffer, "[%u/%u]%s",
				defraged_file_count, total_count, file);
		if (current_uid == ROOT_UID) {
			if (strlen(msg_buffer) > 40)
				printf("\033[79;0H\033[K%s\n"
						"%50d/%-10d%8.2f%%\n",
						msg_buffer, now_ext_count,
						best_ext_count, ratio);
			else
				printf("\033[79;0H\033[K%-40s"
						"%10d/%-10d%8.2f%%\n",
						msg_buffer, now_ext_count,
						best_ext_count, ratio);
		} else {
			if (strlen(msg_buffer) > 40)
				printf("\033[79;0H\033[K%s\n%50d/%-10s%7s\n",
						msg_buffer, now_ext_count,
							"-", "-");
			else
				printf("\033[79;0H\033[K%-40s%10d/%-10s%7s\n",
						msg_buffer, now_ext_count,
							"-", "-");
		}
	}

	for (i = 0; i < SHOW_FRAG_FILES; i++) {
		if (ratio >= frag_rank[i].ratio) {
			for (j = SHOW_FRAG_FILES - 1; j > i; j--) {
				memcpy(&frag_rank[j], &frag_rank[j - 1],
					sizeof(struct frag_statistic_ino));
			}
			memset(&frag_rank[i], 0,
					sizeof(struct frag_statistic_ino));
			strncpy(frag_rank[i].msg_buffer, file,
						strnlen(file, PATH_MAX));
			frag_rank[i].now_count = now_ext_count;
			frag_rank[i].best_count = best_ext_count;
			frag_rank[i].ratio = ratio;
			break;
		}
	}

	succeed_cnt++;

out:
	close(fd);
	free_ext(physical_list_head);
	free_ext(logical_list_head);
	return 0;
}

/*
 * print_progress -	Print defrag progress
 *
 * @file:		file name.
 * @start:		logical offset for defrag target file
 * @file_size:		defrag target filesize
 */
static void print_progress(const char *file, loff_t start, loff_t file_size)
{
	int percent = (start * 100) / file_size;
	printf("\033[79;0H\033[K[%u/%u]%s:\t%3d%%",
		defraged_file_count, total_count, file, min(percent, 100));
	fflush(stdout);

	return;
}

/*
 * call_defrag() -	Execute the defrag program.
 *
 * @fd:			target file descriptor.
 * @donor_fd:		donor file descriptor.
 * @file:			target file name.
 * @buf:			pointer of the struct stat64.
 * @ext_list_head:	head of the extent list.
 */
static int call_defrag(int fd, int donor_fd, const char *file,
	const struct stat64 *buf, struct fiemap_extent_list *ext_list_head)
{
	loff_t	start = 0;
	unsigned int	page_num;
	unsigned char	*vec = NULL;
	int	defraged_ret = 0;
	int	ret;
	struct move_extent	move_data;
	struct fiemap_extent_list	*ext_list_tmp = NULL;

	memset(&move_data, 0, sizeof(struct move_extent));
	move_data.donor_fd = donor_fd;

	/* Print defrag progress */
	print_progress(file, start, buf->st_size);

	ext_list_tmp = ext_list_head;
	do {
		move_data.orig_start = ext_list_tmp->data.logical;
		/* Logical offset of orig and donor should be same */
		move_data.donor_start = move_data.orig_start;
		move_data.len = ext_list_tmp->data.len;
		move_data.moved_len = 0;

		ret = page_in_core(fd, move_data, &vec, &page_num);
		if (ret < 0) {
			if (mode_flag & DETAIL) {
				printf("\n");
				PRINT_ERR_MSG_WITH_ERRNO(
						"Failed to get file map");
			} else {
				printf("\t[ NG ]\n");
			}
			return -1;
		}

		/* EXT4_IOC_MOVE_EXT */
		defraged_ret =
			ioctl(fd, EXT4_IOC_MOVE_EXT, &move_data);

		/* Free pages */
		ret = defrag_fadvise(fd, move_data, vec, page_num);
		if (vec) {
			free(vec);
			vec = NULL;
		}
		if (ret < 0) {
			if (mode_flag & DETAIL) {
				printf("\n");
				PRINT_ERR_MSG_WITH_ERRNO(
					"Failed to free page");
			} else {
				printf("\t[ NG ]\n");
			}
			return -1;
		}

		if (defraged_ret < 0) {
			if (mode_flag & DETAIL) {
				printf("\n");
				PRINT_ERR_MSG_WITH_ERRNO(
						"Failed to defrag");
			} else {
				printf("\t[ NG ]\n");
			}
			return -1;
		}
		/* Adjust logical offset for next ioctl */
		move_data.orig_start += move_data.moved_len;
		move_data.donor_start = move_data.orig_start;

		start = move_data.orig_start * buf->st_blksize;

		/* Print defrag progress */
		print_progress(file, start, buf->st_size);

		/* End of file */
		if (start >= buf->st_size)
			break;

		ext_list_tmp = ext_list_tmp->next;
	} while (ext_list_tmp != ext_list_head);

	return 0;
}

/*
 * file_defrag() -		Check file attributes and call ioctl to defrag.
 *
 * @file:		the file's name.
 * @buf:		the pointer of the struct stat64.
 * @flag:		file type.
 * @ftwbuf:		the pointer of a struct FTW.
 */
static int file_defrag(const char *file, const struct stat64 *buf,
			int flag EXT2FS_ATTR((unused)),
			struct FTW *ftwbuf EXT2FS_ATTR((unused)))
{
	int	fd;
	int	donor_fd = -1;
	int	ret;
	int	best;
	int	file_frags_start, file_frags_end;
	int	orig_physical_cnt, donor_physical_cnt = 0;
	char	tmp_inode_name[PATH_MAX + 8];
	struct fiemap_extent_list	*orig_list_physical = NULL;
	struct fiemap_extent_list	*orig_list_logical = NULL;
	struct fiemap_extent_list	*donor_list_physical = NULL;
	struct fiemap_extent_list	*donor_list_logical = NULL;
	struct fiemap_extent_group	*orig_group_head = NULL;
	struct fiemap_extent_group	*orig_group_tmp = NULL;

	defraged_file_count++;

	if (mode_flag & DETAIL) {
		printf("[%u/%u]", defraged_file_count, total_count);
		fflush(stdout);
	}

	if (lost_found_dir[0] != '\0' &&
	    !memcmp(file, lost_found_dir, strnlen(lost_found_dir, PATH_MAX))) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			IN_FTW_PRINT_ERR_MSG(NGMSG_LOST_FOUND);
		}
		return 0;
	}

	if (!S_ISREG(buf->st_mode)) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			IN_FTW_PRINT_ERR_MSG(NGMSG_FILE_UNREG);
		}
		return 0;
	}

	/* Empty file */
	if (buf->st_size == 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			IN_FTW_PRINT_ERR_MSG("File size is 0");
		}
		return 0;
	}

	/* Has no blocks */
	if (buf->st_blocks == 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			STATISTIC_ERR_MSG("File has no blocks");
		}
		return 0;
	}

	fd = open64(file, O_RDWR);
	if (fd < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_OPEN);
		}
		return 0;
	}

	/* Get file's extents */
	ret = get_file_extents(fd, &orig_list_physical);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_EXTENT);
		}
		goto out;
	}

	/* Get the count of file's continuous physical region */
	orig_physical_cnt = get_physical_count(orig_list_physical);

	/* Change list from physical to logical */
	ret = change_physical_to_logical(&orig_list_physical,
							&orig_list_logical);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_EXTENT);
		}
		goto out;
	}

	/* Count file fragments before defrag */
	file_frags_start = get_logical_count(orig_list_logical);

	if (file_check(fd, buf, file, file_frags_start) < 0)
		goto out;

	if (fsync(fd) < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO("Failed to sync(fsync)");
		}
		goto out;
	}

	if (current_uid == ROOT_UID)
		best =
		get_best_count(SECTOR_TO_BLOCK(buf->st_blocks, block_size));
	else
		best = 1;

	if (file_frags_start <= best)
		goto check_improvement;

	/* Combine extents to group */
	ret = join_extents(orig_list_logical, &orig_group_head);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_EXTENT);
		}
		goto out;
	}

	/* Create donor inode */
	memset(tmp_inode_name, 0, PATH_MAX + 8);
	sprintf(tmp_inode_name, "%.*s.defrag",
				(int)strnlen(file, PATH_MAX), file);
	donor_fd = open64(tmp_inode_name, O_WRONLY | O_CREAT | O_EXCL, S_IRUSR);
	if (donor_fd < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			if (errno == EEXIST)
				PRINT_ERR_MSG_WITH_ERRNO(
				"File is being defraged by other program");
			else
				PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_OPEN);
		}
		goto out;
	}

	/* Unlink donor inode */
	ret = unlink(tmp_inode_name);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO("Failed to unlink");
		}
		goto out;
	}

	/* Allocate space for donor inode */
	orig_group_tmp = orig_group_head;
	do {
		ret = fallocate(donor_fd, 0,
		  (loff_t)orig_group_tmp->start->data.logical * block_size,
		  (loff_t)orig_group_tmp->len * block_size);
		if (ret < 0) {
			if (mode_flag & DETAIL) {
				PRINT_FILE_NAME(file);
				PRINT_ERR_MSG_WITH_ERRNO("Failed to fallocate");
			}
			goto out;
		}

		orig_group_tmp = orig_group_tmp->next;
	} while (orig_group_tmp != orig_group_head);

	/* Get donor inode's extents */
	ret = get_file_extents(donor_fd, &donor_list_physical);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_EXTENT);
		}
		goto out;
	}

	/* Calcuate donor inode's continuous physical region */
	donor_physical_cnt = get_physical_count(donor_list_physical);

	/* Change donor extent list from physical to logical */
	ret = change_physical_to_logical(&donor_list_physical,
							&donor_list_logical);
	if (ret < 0) {
		if (mode_flag & DETAIL) {
			PRINT_FILE_NAME(file);
			PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_EXTENT);
		}
		goto out;
	}

check_improvement:
	if (mode_flag & DETAIL) {
		if (file_frags_start != 1)
			frag_files_before_defrag++;

		extents_before_defrag += file_frags_start;
	}

	if (file_frags_start <= best ||
			orig_physical_cnt <= donor_physical_cnt) {
		printf("\033[79;0H\033[K[%u/%u]%s:\t%3d%%",
			defraged_file_count, total_count, file, 100);
		if (mode_flag & DETAIL)
			printf("  extents: %d -> %d",
				file_frags_start, file_frags_start);

		printf("\t[ OK ]\n");
		succeed_cnt++;

		if (file_frags_start != 1)
			frag_files_after_defrag++;

		extents_after_defrag += file_frags_start;
		goto out;
	}

	/* Defrag the file */
	ret = call_defrag(fd, donor_fd, file, buf, donor_list_logical);

	/* Count file fragments after defrag and print extents info */
	if (mode_flag & DETAIL) {
		file_frags_end = file_frag_count(fd);
		if (file_frags_end < 0) {
			printf("\n");
			PRINT_ERR_MSG_WITH_ERRNO(NGMSG_FILE_INFO);
			goto out;
		}

		if (file_frags_end != 1)
			frag_files_after_defrag++;

		extents_after_defrag += file_frags_end;

		if (ret < 0)
			goto out;

		printf("  extents: %d -> %d",
			file_frags_start, file_frags_end);
		fflush(stdout);
	}

	if (ret < 0)
		goto out;

	printf("\t[ OK ]\n");
	fflush(stdout);
	succeed_cnt++;

out:
	close(fd);
	if (donor_fd != -1)
		close(donor_fd);
	free_ext(orig_list_physical);
	free_ext(orig_list_logical);
	free_ext(donor_list_physical);
	free_exts_group(orig_group_head);
	return 0;
}

/*
 * main() -		Ext4 online defrag.
 *
 * @argc:		the number of parameter.
 * @argv[]:		the pointer array of parameter.
 */
int main(int argc, char *argv[])
{
	int	opt;
	int	i, j;
	int	flags = FTW_PHYS | FTW_MOUNT;
	int	arg_type = -1;
	int	success_flag = 0;
	char	dir_name[PATH_MAX + 1];
	struct stat64	buf;
	struct ext4_super_block sb;

	/* Parse arguments */
	if (argc == 1)
		goto out;

	while ((opt = getopt(argc, argv, "vc")) != EOF) {
		switch (opt) {
		case 'v':
			mode_flag |= DETAIL;
			break;
		case 'c':
			mode_flag |= STATISTIC;
			break;
		default:
			goto out;
		}
	}

	if (argc == optind)
		goto out;

	current_uid = getuid();

	/* Main process */
	for (i = optind; i < argc; i++) {
		succeed_cnt = 0;
		regular_count = 0;
		total_count = 0;
		frag_files_before_defrag = 0;
		frag_files_after_defrag = 0;
		extents_before_defrag = 0;
		extents_after_defrag = 0;
		defraged_file_count = 0;
		files_block_count = 0;
		blocks_per_group = 0;
		feature_incompat = 0;
		log_groups_per_flex = 0;

		memset(dir_name, 0, PATH_MAX + 1);
		memset(lost_found_dir, 0, PATH_MAX + 1);
		memset(frag_rank, 0,
			sizeof(struct frag_statistic_ino) * SHOW_FRAG_FILES);

		if ((mode_flag & STATISTIC) && i > optind)
			printf("\n");

#if BYTE_ORDER != BIG_ENDIAN && BYTE_ORDER != LITTLE_ENDIAN
		PRINT_ERR_MSG("Endian's type is not big/little endian");
		PRINT_FILE_NAME(argv[i]);
		continue;
#endif

		if (lstat64(argv[i], &buf) < 0) {
			perror(NGMSG_FILE_INFO);
			PRINT_FILE_NAME(argv[i]);
			continue;
		}

		if (S_ISBLK(buf.st_mode)) {
			/* Block device */
			if (get_mount_point(argv[i], dir_name, PATH_MAX) < 0)
				continue;
			if (lstat64(dir_name, &buf) < 0) {
				perror(NGMSG_FILE_INFO);
				PRINT_FILE_NAME(argv[i]);
				continue;
			}
			arg_type = DEVNAME;
			if (!(mode_flag & STATISTIC))
				printf("ext4 defragmentation for device(%s)\n",
					argv[i]);
		} else if (S_ISDIR(buf.st_mode)) {
			/* Directory */
			if (access(argv[i], R_OK) < 0) {
				perror(argv[i]);
				continue;
			}
			arg_type = DIRNAME;
			strncpy(dir_name, argv[i], strnlen(argv[i], PATH_MAX));
		} else if (S_ISREG(buf.st_mode)) {
			/* Regular file */
			arg_type = FILENAME;
		} else {
			/* Irregular file */
			PRINT_ERR_MSG(NGMSG_FILE_UNREG);
			PRINT_FILE_NAME(argv[i]);
			continue;
		}

		/* Set blocksize */
		block_size = buf.st_blksize;

		/* For device case,
		 * filesystem type checked in get_mount_point()
		 */
		if (arg_type == FILENAME || arg_type == DIRNAME) {
			if (is_ext4(argv[i]) < 0)
				continue;
			if (realpath(argv[i], dir_name) == NULL) {
				perror("Couldn't get full path");
				PRINT_FILE_NAME(argv[i]);
				continue;
			}
		}

		if (current_uid == ROOT_UID) {
			/* Get super block info */
			memset(&sb, 0, sizeof(struct ext4_super_block));
			if (get_superblock_info(dir_name, &sb) < 0) {
				if (mode_flag & DETAIL) {
					perror("Can't get super block info");
					PRINT_FILE_NAME(argv[i]);
				}
				continue;
			}

			blocks_per_group = ext2fs_swab32(sb.s_blocks_per_group);
			feature_incompat = ext2fs_swab32(sb.s_feature_incompat);
			log_groups_per_flex = sb.s_log_groups_per_flex;
		}

		switch (arg_type) {
		case DIRNAME:
			if (!(mode_flag & STATISTIC))
				printf("ext4 defragmentation "
					"for directory(%s)\n", argv[i]);

			int mount_dir_len = 0;
			mount_dir_len = strnlen(lost_found_dir, PATH_MAX);

			strncat(lost_found_dir, "/lost+found",
				PATH_MAX - strnlen(lost_found_dir, PATH_MAX));

			/* Not the case("e4defrag  mount_piont_dir") */
			if (dir_name[mount_dir_len] != '\0') {
				/*
				 * "e4defrag mount_piont_dir/lost+found"
				 * or "e4defrag mount_piont_dir/lost+found/"
				 */
				if (strncmp(lost_found_dir, dir_name,
					    strnlen(lost_found_dir,
						    PATH_MAX)) == 0 &&
				    (dir_name[strnlen(lost_found_dir,
						      PATH_MAX)] == '\0' ||
				     dir_name[strnlen(lost_found_dir,
						      PATH_MAX)] == '/')) {
					PRINT_ERR_MSG(NGMSG_LOST_FOUND);
					PRINT_FILE_NAME(argv[i]);
					continue;
				}

				/* "e4defrag mount_piont_dir/else_dir" */
				memset(lost_found_dir, 0, PATH_MAX + 1);
			}
		case DEVNAME:
			if (arg_type == DEVNAME) {
				strncpy(lost_found_dir, dir_name,
					strnlen(dir_name, PATH_MAX));
				strncat(lost_found_dir, "/lost+found/",
					PATH_MAX - strnlen(lost_found_dir,
							   PATH_MAX));
			}

			nftw64(dir_name, calc_entry_counts, FTW_OPEN_FD, flags);

			if (mode_flag & STATISTIC) {
				if (mode_flag & DETAIL)
					printf("%-40s%10s/%-10s%9s\n",
					"<File>", "now", "best", "ratio");

				if (!(mode_flag & DETAIL) &&
						current_uid != ROOT_UID) {
					printf(" Done.\n");
					continue;
				}

				nftw64(dir_name, file_statistic,
							FTW_OPEN_FD, flags);

				if (succeed_cnt != 0 &&
					current_uid == ROOT_UID) {
					if (mode_flag & DETAIL)
						printf("\n");
					printf("%-40s%10s/%-10s%9s\n",
						"<Fragmented files>", "now",
						"best", "ratio");
					for (j = 0; j < SHOW_FRAG_FILES; j++) {
						if (strlen(frag_rank[j].
							msg_buffer) > 37) {
							printf("%d. %s\n%50d/"
							"%-10d%8.2f%%\n", j + 1,
							frag_rank[j].msg_buffer,
							frag_rank[j].now_count,
							frag_rank[j].best_count,
							frag_rank[j].ratio);
						} else if (strlen(frag_rank[j].
							msg_buffer) > 0) {
							printf("%d. %-37s%10d/"
							"%-10d%8.2f%%\n", j + 1,
							frag_rank[j].msg_buffer,
							frag_rank[j].now_count,
							frag_rank[j].best_count,
							frag_rank[j].ratio);
						} else
							break;
					}
				}
				break;
			}
			/* File tree walk */
			nftw64(dir_name, file_defrag, FTW_OPEN_FD, flags);
			printf("\n\tSuccess:\t\t\t[ %u/%u ]\n", succeed_cnt,
				total_count);
			printf("\tFailure:\t\t\t[ %u/%u ]\n",
				total_count - succeed_cnt, total_count);
			if (mode_flag & DETAIL) {
				printf("\tTotal extents:\t\t\t%4d->%d\n",
					extents_before_defrag,
					extents_after_defrag);
				printf("\tFragmented percentage:\t\t"
					"%3llu%%->%llu%%\n",
					!regular_count ? 0 :
					((unsigned long long)
					frag_files_before_defrag * 100) /
					regular_count,
					!regular_count ? 0 :
					((unsigned long long)
					frag_files_after_defrag * 100) /
					regular_count);
			}
			break;
		case FILENAME:
			total_count = 1;
			regular_count = 1;
			strncat(lost_found_dir, "/lost+found/",
				PATH_MAX - strnlen(lost_found_dir,
						   PATH_MAX));
			if (strncmp(lost_found_dir, dir_name,
				    strnlen(lost_found_dir,
					    PATH_MAX)) == 0) {
				PRINT_ERR_MSG(NGMSG_LOST_FOUND);
				PRINT_FILE_NAME(argv[i]);
				continue;
			}

			if (mode_flag & STATISTIC) {
				file_statistic(argv[i], &buf, FTW_F, NULL);
				break;
			} else
				printf("ext4 defragmentation for %s\n",
								 argv[i]);
			/* Defrag single file process */
			file_defrag(argv[i], &buf, FTW_F, NULL);
			if (succeed_cnt != 0)
				printf(" Success:\t\t\t[1/1]\n");
			else
				printf(" Success:\t\t\t[0/1]\n");

			break;
		}

		if (succeed_cnt != 0)
			success_flag = 1;
		if (mode_flag & STATISTIC) {
			if (current_uid != ROOT_UID) {
				printf(" Done.\n");
				continue;
			}

			if (!succeed_cnt) {
				if (mode_flag & DETAIL)
					printf("\n");

				if (arg_type == DEVNAME)
					printf(" In this device(%s), "
					"none can be defragmented.\n", argv[i]);
				else if (arg_type == DIRNAME)
					printf(" In this directory(%s), "
					"none can be defragmented.\n", argv[i]);
				else
					printf(" This file(%s) "
					"can't be defragmented.\n", argv[i]);
			} else {
				float files_ratio = 0.0;
				float score = 0.0;
				files_ratio = (float)(extents_before_defrag -
						extents_after_defrag) *
						100 / files_block_count;
				score = CALC_SCORE(files_ratio);
				printf("\n Total/best extents\t\t\t\t%d/%d\n"
					" Fragmentation ratio\t\t\t\t%.2f%%\n"
					" Fragmentation score\t\t\t\t%.2f\n",
						extents_before_defrag,
						extents_after_defrag,
						files_ratio, score);
				printf(" [0-30 no problem:"
					" 31-55 a little bit fragmented:"
					" 55- needs defrag]\n");

				if (arg_type == DEVNAME)
					printf(" This device(%s) ", argv[i]);
				else if (arg_type == DIRNAME)
					printf(" This directory(%s) ", argv[i]);
				else
					printf(" This file(%s) ", argv[i]);

				if (score > BOUND_SCORE)
					printf("needs defragmentation.\n");
				else
					printf("does not need "
							"defragmentation.\n");
			}
			printf(" Done.\n");
		}

	}

	if (success_flag)
		return 0;

	exit(1);

out:
	printf(MSG_USAGE);
	exit(1);
}