[deliverable/linux.git] / fs / nilfs2 / the_nilfs.h

/*
 * the_nilfs.h - the_nilfs shared structure.
 *
 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Written by Ryusuke Konishi.
 *
 */

#ifndef _THE_NILFS_H
#define _THE_NILFS_H

#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/rbtree.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
#include <linux/slab.h>

struct nilfs_sc_info;
struct nilfs_sysfs_dev_subgroups;

/* the_nilfs struct */
enum {
	THE_NILFS_INIT = 0,     /* Information from super_block is set */
	THE_NILFS_DISCONTINUED,	/* 'next' pointer chain has broken */
	THE_NILFS_GC_RUNNING,	/* gc process is running */
	THE_NILFS_SB_DIRTY,	/* super block is dirty */
};

/**
 * struct the_nilfs - struct to supervise multiple nilfs mount points
 * @ns_flags: flags
 * @ns_flushed_device: flag indicating if all volatile data was flushed
 * @ns_bdev: block device
 * @ns_sem: semaphore for shared states
 * @ns_snapshot_mount_mutex: mutex to protect snapshot mounts
 * @ns_sbh: buffer heads of on-disk super blocks
 * @ns_sbp: pointers to super block data
 * @ns_sbwtime: previous write time of super block
 * @ns_sbwcount: write count of super block
 * @ns_sbsize: size of valid data in super block
 * @ns_mount_state: file system state
 * @ns_sb_update_freq: interval of periodical update of superblocks (in seconds)
 * @ns_seg_seq: segment sequence counter
 * @ns_segnum: index number of the latest full segment.
 * @ns_nextnum: index number of the full segment index to be used next
 * @ns_pseg_offset: offset of next partial segment in the current full segment
 * @ns_cno: next checkpoint number
 * @ns_ctime: write time of the last segment
 * @ns_nongc_ctime: write time of the last segment not for cleaner operation
 * @ns_ndirtyblks: Number of dirty data blocks
 * @ns_last_segment_lock: lock protecting fields for the latest segment
 * @ns_last_pseg: start block number of the latest segment
 * @ns_last_seq: sequence value of the latest segment
 * @ns_last_cno: checkpoint number of the latest segment
 * @ns_prot_seq: least sequence number of segments which must not be reclaimed
 * @ns_prev_seq: base sequence number used to decide if advance log cursor
 * @ns_writer: log writer
 * @ns_segctor_sem: semaphore protecting log write
 * @ns_dat: DAT file inode
 * @ns_cpfile: checkpoint file inode
 * @ns_sufile: segusage file inode
 * @ns_cptree: rb-tree of all mounted checkpoints (nilfs_root)
 * @ns_cptree_lock: lock protecting @ns_cptree
 * @ns_dirty_files: list of dirty files
 * @ns_inode_lock: lock protecting @ns_dirty_files
 * @ns_gc_inodes: dummy inodes to keep live blocks
 * @ns_next_generation: next generation number for inodes
 * @ns_next_gen_lock: lock protecting @ns_next_generation
 * @ns_mount_opt: mount options
 * @ns_resuid: uid for reserved blocks
 * @ns_resgid: gid for reserved blocks
 * @ns_interval: checkpoint creation interval
 * @ns_watermark: watermark for the number of dirty buffers
 * @ns_blocksize_bits: bit length of block size
 * @ns_blocksize: block size
 * @ns_nsegments: number of segments in filesystem
 * @ns_blocks_per_segment: number of blocks per segment
 * @ns_r_segments_percentage: reserved segments percentage
 * @ns_nrsvsegs: number of reserved segments
 * @ns_first_data_block: block number of first data block
 * @ns_inode_size: size of on-disk inode
 * @ns_first_ino: first not-special inode number
 * @ns_crc_seed: seed value of CRC32 calculation
 * @ns_dev_kobj: /sys/fs/<nilfs>/<device>
 * @ns_dev_kobj_unregister: completion state
 * @ns_dev_subgroups: <device> subgroups pointer
 */
struct the_nilfs {
	unsigned long		ns_flags;
	int			ns_flushed_device;

	struct block_device    *ns_bdev;
	struct rw_semaphore	ns_sem;
	struct mutex		ns_snapshot_mount_mutex;

	/*
	 * used for
	 * - loading the latest checkpoint exclusively.
	 * - allocating a new full segment.
	 */
	struct buffer_head     *ns_sbh[2];
	struct nilfs_super_block *ns_sbp[2];
	time_t			ns_sbwtime;
	unsigned int		ns_sbwcount;
	unsigned int		ns_sbsize;
	unsigned int		ns_mount_state;
	unsigned int		ns_sb_update_freq;

	/*
	 * Following fields are dedicated to a writable FS-instance.
	 * Except for the period seeking checkpoint, code outside the segment
	 * constructor must lock a segment semaphore while accessing these
	 * fields.
	 * The writable FS-instance is sole during a lifetime of the_nilfs.
	 */
	u64			ns_seg_seq;
	__u64			ns_segnum;
	__u64			ns_nextnum;
	unsigned long		ns_pseg_offset;
	__u64			ns_cno;
	time_t			ns_ctime;
	time_t			ns_nongc_ctime;
	atomic_t		ns_ndirtyblks;

	/*
	 * The following fields hold information on the latest partial segment
	 * written to disk with a super root.  These fields are protected by
	 * ns_last_segment_lock.
	 */
	spinlock_t		ns_last_segment_lock;
	sector_t		ns_last_pseg;
	u64			ns_last_seq;
	__u64			ns_last_cno;
	u64			ns_prot_seq;
	u64			ns_prev_seq;

	struct nilfs_sc_info   *ns_writer;
	struct rw_semaphore	ns_segctor_sem;

	/*
	 * Following fields are lock free except for the period before
	 * the_nilfs is initialized.
	 */
	struct inode	       *ns_dat;
	struct inode	       *ns_cpfile;
	struct inode	       *ns_sufile;

	/* Checkpoint tree */
	struct rb_root		ns_cptree;
	spinlock_t		ns_cptree_lock;

	/* Dirty inode list */
	struct list_head	ns_dirty_files;
	spinlock_t		ns_inode_lock;

	/* GC inode list */
	struct list_head	ns_gc_inodes;

	/* Inode allocator */
	u32			ns_next_generation;
	spinlock_t		ns_next_gen_lock;

	/* Mount options */
	unsigned long		ns_mount_opt;

	uid_t			ns_resuid;
	gid_t			ns_resgid;
	unsigned long		ns_interval;
	unsigned long		ns_watermark;

	/* Disk layout information (static) */
	unsigned int		ns_blocksize_bits;
	unsigned int		ns_blocksize;
	unsigned long		ns_nsegments;
	unsigned long		ns_blocks_per_segment;
	unsigned long		ns_r_segments_percentage;
	unsigned long		ns_nrsvsegs;
	unsigned long		ns_first_data_block;
	int			ns_inode_size;
	int			ns_first_ino;
	u32			ns_crc_seed;

	/* /sys/fs/<nilfs>/<device> */
	struct kobject ns_dev_kobj;
	struct completion ns_dev_kobj_unregister;
	struct nilfs_sysfs_dev_subgroups *ns_dev_subgroups;
};

#define THE_NILFS_FNS(bit, name)					\
static inline void set_nilfs_##name(struct the_nilfs *nilfs)		\
{									\
	set_bit(THE_NILFS_##bit, &(nilfs)->ns_flags);			\
}									\
static inline void clear_nilfs_##name(struct the_nilfs *nilfs)		\
{									\
	clear_bit(THE_NILFS_##bit, &(nilfs)->ns_flags);			\
}									\
static inline int nilfs_##name(struct the_nilfs *nilfs)			\
{									\
	return test_bit(THE_NILFS_##bit, &(nilfs)->ns_flags);		\
}

THE_NILFS_FNS(INIT, init)
THE_NILFS_FNS(DISCONTINUED, discontinued)
THE_NILFS_FNS(GC_RUNNING, gc_running)
THE_NILFS_FNS(SB_DIRTY, sb_dirty)

/*
 * Mount option operations
 */
#define nilfs_clear_opt(nilfs, opt)  \
	do { (nilfs)->ns_mount_opt &= ~NILFS_MOUNT_##opt; } while (0)
#define nilfs_set_opt(nilfs, opt)  \
	do { (nilfs)->ns_mount_opt |= NILFS_MOUNT_##opt; } while (0)
#define nilfs_test_opt(nilfs, opt) ((nilfs)->ns_mount_opt & NILFS_MOUNT_##opt)
#define nilfs_write_opt(nilfs, mask, opt)				\
	do { (nilfs)->ns_mount_opt =					\
		(((nilfs)->ns_mount_opt & ~NILFS_MOUNT_##mask) |	\
		 NILFS_MOUNT_##opt);					\
	} while (0)

/**
 * struct nilfs_root - nilfs root object
 * @cno: checkpoint number
 * @rb_node: red-black tree node
 * @count: refcount of this structure
 * @nilfs: nilfs object
 * @ifile: inode file
 * @inodes_count: number of inodes
 * @blocks_count: number of blocks
 * @snapshot_kobj: /sys/fs/<nilfs>/<device>/mounted_snapshots/<snapshot>
 * @snapshot_kobj_unregister: completion state for kernel object
 */
struct nilfs_root {
	__u64 cno;
	struct rb_node rb_node;

	atomic_t count;
	struct the_nilfs *nilfs;
	struct inode *ifile;

	atomic64_t inodes_count;
	atomic64_t blocks_count;

	/* /sys/fs/<nilfs>/<device>/mounted_snapshots/<snapshot> */
	struct kobject snapshot_kobj;
	struct completion snapshot_kobj_unregister;
};

/* Special checkpoint number */
#define NILFS_CPTREE_CURRENT_CNO	0

/* Minimum interval of periodical update of superblocks (in seconds) */
#define NILFS_SB_FREQ		10

static inline int nilfs_sb_need_update(struct the_nilfs *nilfs)
{
	u64 t = get_seconds();

	return t < nilfs->ns_sbwtime ||
		t > nilfs->ns_sbwtime + nilfs->ns_sb_update_freq;
}

static inline int nilfs_sb_will_flip(struct the_nilfs *nilfs)
{
	int flip_bits = nilfs->ns_sbwcount & 0x0FL;

	return (flip_bits != 0x08 && flip_bits != 0x0F);
}

void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64);
struct the_nilfs *alloc_nilfs(struct block_device *bdev);
void destroy_nilfs(struct the_nilfs *nilfs);
int init_nilfs(struct the_nilfs *nilfs, struct super_block *sb, char *data);
int load_nilfs(struct the_nilfs *nilfs, struct super_block *sb);
unsigned long nilfs_nrsvsegs(struct the_nilfs *nilfs, unsigned long nsegs);
void nilfs_set_nsegments(struct the_nilfs *nilfs, unsigned long nsegs);
int nilfs_discard_segments(struct the_nilfs *, __u64 *, size_t);
int nilfs_count_free_blocks(struct the_nilfs *, sector_t *);
struct nilfs_root *nilfs_lookup_root(struct the_nilfs *nilfs, __u64 cno);
struct nilfs_root *nilfs_find_or_create_root(struct the_nilfs *nilfs,
					     __u64 cno);
void nilfs_put_root(struct nilfs_root *root);
int nilfs_near_disk_full(struct the_nilfs *);
void nilfs_fall_back_super_block(struct the_nilfs *);
void nilfs_swap_super_block(struct the_nilfs *);


static inline void nilfs_get_root(struct nilfs_root *root)
{
	atomic_inc(&root->count);
}

static inline int nilfs_valid_fs(struct the_nilfs *nilfs)
{
	unsigned int valid_fs;

	down_read(&nilfs->ns_sem);
	valid_fs = (nilfs->ns_mount_state & NILFS_VALID_FS);
	up_read(&nilfs->ns_sem);
	return valid_fs;
}

static inline void
nilfs_get_segment_range(struct the_nilfs *nilfs, __u64 segnum,
			sector_t *seg_start, sector_t *seg_end)
{
	*seg_start = (sector_t)nilfs->ns_blocks_per_segment * segnum;
	*seg_end = *seg_start + nilfs->ns_blocks_per_segment - 1;
	if (segnum == 0)
		*seg_start = nilfs->ns_first_data_block;
}

static inline sector_t
nilfs_get_segment_start_blocknr(struct the_nilfs *nilfs, __u64 segnum)
{
	return (segnum == 0) ? nilfs->ns_first_data_block :
		(sector_t)nilfs->ns_blocks_per_segment * segnum;
}

static inline __u64
nilfs_get_segnum_of_block(struct the_nilfs *nilfs, sector_t blocknr)
{
	sector_t segnum = blocknr;

	sector_div(segnum, nilfs->ns_blocks_per_segment);
	return segnum;
}

static inline void
nilfs_terminate_segment(struct the_nilfs *nilfs, sector_t seg_start,
			sector_t seg_end)
{
	/* terminate the current full segment (used in case of I/O-error) */
	nilfs->ns_pseg_offset = seg_end - seg_start + 1;
}

static inline void nilfs_shift_to_next_segment(struct the_nilfs *nilfs)
{
	/* move forward with a full segment */
	nilfs->ns_segnum = nilfs->ns_nextnum;
	nilfs->ns_pseg_offset = 0;
	nilfs->ns_seg_seq++;
}

static inline __u64 nilfs_last_cno(struct the_nilfs *nilfs)
{
	__u64 cno;

	spin_lock(&nilfs->ns_last_segment_lock);
	cno = nilfs->ns_last_cno;
	spin_unlock(&nilfs->ns_last_segment_lock);
	return cno;
}

static inline int nilfs_segment_is_active(struct the_nilfs *nilfs, __u64 n)
{
	return n == nilfs->ns_segnum || n == nilfs->ns_nextnum;
}

static inline int nilfs_flush_device(struct the_nilfs *nilfs)
{
	int err;

	if (!nilfs_test_opt(nilfs, BARRIER) || nilfs->ns_flushed_device)
		return 0;

	nilfs->ns_flushed_device = 1;
	/*
	 * the store to ns_flushed_device must not be reordered after
	 * blkdev_issue_flush().
	 */
	smp_wmb();

	err = blkdev_issue_flush(nilfs->ns_bdev, GFP_KERNEL, NULL);
	if (err != -EIO)
		err = 0;
	return err;
}

#endif /* _THE_NILFS_H */
Commit	Line	Data
65b4643d RK	1	/*
	2	* the_nilfs.h - the_nilfs shared structure.
	3	*
	4	* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
4b420ab4	16	* Written by Ryusuke Konishi.
65b4643d RK	17	*
	18	*/
	19
	20	#ifndef _THE_NILFS_H
	21	#define _THE_NILFS_H
	22
	23	#include <linux/types.h>
	24	#include <linux/buffer_head.h>
ba65ae47	25	#include <linux/rbtree.h>
65b4643d RK	26	#include <linux/fs.h>
	27	#include <linux/blkdev.h>
	28	#include <linux/backing-dev.h>
5a0e3ad6	29	#include <linux/slab.h>
65b4643d	30
3fd3fe5a	31	struct nilfs_sc_info;
caa05d49	32	struct nilfs_sysfs_dev_subgroups;
3fd3fe5a	33
65b4643d RK	34	/* the_nilfs struct */
	35	enum {
	36	THE_NILFS_INIT = 0, /* Information from super_block is set */
65b4643d	37	THE_NILFS_DISCONTINUED, /* 'next' pointer chain has broken */
1cf58fa8	38	THE_NILFS_GC_RUNNING, /* gc process is running */
e605f0a7	39	THE_NILFS_SB_DIRTY, /* super block is dirty */
65b4643d RK	40	};
	41
	42	/**
	43	* struct the_nilfs - struct to supervise multiple nilfs mount points
	44	* @ns_flags: flags
e2c7617a	45	* @ns_flushed_device: flag indicating if all volatile data was flushed
65b4643d	46	* @ns_bdev: block device
65b4643d	47	* @ns_sem: semaphore for shared states
572d8b39	48	* @ns_snapshot_mount_mutex: mutex to protect snapshot mounts
e339ad31 RK	49	* @ns_sbh: buffer heads of on-disk super blocks
e339ad31 RK	50	* @ns_sbp: pointers to super block data
b2ac86e1 JS	51	* @ns_sbwtime: previous write time of super block
b2ac86e1 JS	52	* @ns_sbwcount: write count of super block
e339ad31	53	* @ns_sbsize: size of valid data in super block
6b0f3393	54	* @ns_mount_state: file system state
caa05d49	55	* @ns_sb_update_freq: interval of periodical update of superblocks (in seconds)
65b4643d RK	56	* @ns_seg_seq: segment sequence counter
	57	* @ns_segnum: index number of the latest full segment.
	58	* @ns_nextnum: index number of the full segment index to be used next
	59	* @ns_pseg_offset: offset of next partial segment in the current full segment
	60	* @ns_cno: next checkpoint number
	61	* @ns_ctime: write time of the last segment
	62	* @ns_nongc_ctime: write time of the last segment not for cleaner operation
	63	* @ns_ndirtyblks: Number of dirty data blocks
	64	* @ns_last_segment_lock: lock protecting fields for the latest segment
	65	* @ns_last_pseg: start block number of the latest segment
	66	* @ns_last_seq: sequence value of the latest segment
	67	* @ns_last_cno: checkpoint number of the latest segment
2c2e52fc	68	* @ns_prot_seq: least sequence number of segments which must not be reclaimed
32502047	69	* @ns_prev_seq: base sequence number used to decide if advance log cursor
3fd3fe5a RK	70	* @ns_writer: log writer
3fd3fe5a RK	71	* @ns_segctor_sem: semaphore protecting log write
65b4643d RK	72	* @ns_dat: DAT file inode
	73	* @ns_cpfile: checkpoint file inode
	74	* @ns_sufile: segusage file inode
ba65ae47 RK	75	* @ns_cptree: rb-tree of all mounted checkpoints (nilfs_root)
ba65ae47 RK	76	* @ns_cptree_lock: lock protecting @ns_cptree
693dd321 RK	77	* @ns_dirty_files: list of dirty files
693dd321 RK	78	* @ns_inode_lock: lock protecting @ns_dirty_files
65b4643d	79	* @ns_gc_inodes: dummy inodes to keep live blocks
9b1fc4e4 RK	80	* @ns_next_generation: next generation number for inodes
9b1fc4e4 RK	81	* @ns_next_gen_lock: lock protecting @ns_next_generation
3b2ce58b	82	* @ns_mount_opt: mount options
574e6c31 RK	83	* @ns_resuid: uid for reserved blocks
	84	* @ns_resgid: gid for reserved blocks
	85	* @ns_interval: checkpoint creation interval
	86	* @ns_watermark: watermark for the number of dirty buffers
65b4643d	87	* @ns_blocksize_bits: bit length of block size
92c60cca	88	* @ns_blocksize: block size
65b4643d RK	89	* @ns_nsegments: number of segments in filesystem
	90	* @ns_blocks_per_segment: number of blocks per segment
	91	* @ns_r_segments_percentage: reserved segments percentage
	92	* @ns_nrsvsegs: number of reserved segments
	93	* @ns_first_data_block: block number of first data block
	94	* @ns_inode_size: size of on-disk inode
	95	* @ns_first_ino: first not-special inode number
	96	* @ns_crc_seed: seed value of CRC32 calculation
da7141fb VD	97	* @ns_dev_kobj: /sys/fs/<nilfs>/<device>
da7141fb VD	98	* @ns_dev_kobj_unregister: completion state
caa05d49	99	* @ns_dev_subgroups: <device> subgroups pointer
65b4643d RK	100	*/
	101	struct the_nilfs {
	102	unsigned long ns_flags;
e2c7617a	103	int ns_flushed_device;
65b4643d RK	104
65b4643d RK	105	struct block_device *ns_bdev;
65b4643d	106	struct rw_semaphore ns_sem;
572d8b39	107	struct mutex ns_snapshot_mount_mutex;
65b4643d RK	108
	109	/*
	110	* used for
	111	* - loading the latest checkpoint exclusively.
	112	* - allocating a new full segment.
65b4643d	113	*/
e339ad31 RK	114	struct buffer_head *ns_sbh[2];
e339ad31 RK	115	struct nilfs_super_block *ns_sbp[2];
b2ac86e1	116	time_t ns_sbwtime;
0c6c44cb RK	117	unsigned int ns_sbwcount;
	118	unsigned int ns_sbsize;
	119	unsigned int ns_mount_state;
	120	unsigned int ns_sb_update_freq;
65b4643d RK	121
	122	/*
	123	* Following fields are dedicated to a writable FS-instance.
	124	* Except for the period seeking checkpoint, code outside the segment
47420c79 RK	125	* constructor must lock a segment semaphore while accessing these
47420c79 RK	126	* fields.
65b4643d RK	127	* The writable FS-instance is sole during a lifetime of the_nilfs.
	128	*/
	129	u64 ns_seg_seq;
	130	__u64 ns_segnum;
	131	__u64 ns_nextnum;
	132	unsigned long ns_pseg_offset;
	133	__u64 ns_cno;
	134	time_t ns_ctime;
	135	time_t ns_nongc_ctime;
	136	atomic_t ns_ndirtyblks;
	137
	138	/*
	139	* The following fields hold information on the latest partial segment
	140	* written to disk with a super root. These fields are protected by
	141	* ns_last_segment_lock.
	142	*/
	143	spinlock_t ns_last_segment_lock;
	144	sector_t ns_last_pseg;
	145	u64 ns_last_seq;
	146	__u64 ns_last_cno;
2c2e52fc	147	u64 ns_prot_seq;
32502047	148	u64 ns_prev_seq;
65b4643d	149
3fd3fe5a	150	struct nilfs_sc_info *ns_writer;
65b4643d RK	151	struct rw_semaphore ns_segctor_sem;
	152
	153	/*
	154	* Following fields are lock free except for the period before
	155	* the_nilfs is initialized.
	156	*/
	157	struct inode *ns_dat;
	158	struct inode *ns_cpfile;
	159	struct inode *ns_sufile;
65b4643d	160
ba65ae47 RK	161	/* Checkpoint tree */
	162	struct rb_root ns_cptree;
	163	spinlock_t ns_cptree_lock;
	164
693dd321 RK	165	/* Dirty inode list */
	166	struct list_head ns_dirty_files;
	167	spinlock_t ns_inode_lock;
	168
263d90ce	169	/* GC inode list */
65b4643d	170	struct list_head ns_gc_inodes;
65b4643d	171
9b1fc4e4 RK	172	/* Inode allocator */
	173	u32 ns_next_generation;
	174	spinlock_t ns_next_gen_lock;
	175
3b2ce58b RK	176	/* Mount options */
	177	unsigned long ns_mount_opt;
	178
574e6c31 RK	179	uid_t ns_resuid;
	180	gid_t ns_resgid;
	181	unsigned long ns_interval;
	182	unsigned long ns_watermark;
	183
65b4643d RK	184	/* Disk layout information (static) */
65b4643d RK	185	unsigned int ns_blocksize_bits;
92c60cca	186	unsigned int ns_blocksize;
65b4643d RK	187	unsigned long ns_nsegments;
	188	unsigned long ns_blocks_per_segment;
	189	unsigned long ns_r_segments_percentage;
	190	unsigned long ns_nrsvsegs;
	191	unsigned long ns_first_data_block;
	192	int ns_inode_size;
	193	int ns_first_ino;
	194	u32 ns_crc_seed;
da7141fb VD	195
	196	/* /sys/fs/<nilfs>/<device> */
	197	struct kobject ns_dev_kobj;
	198	struct completion ns_dev_kobj_unregister;
caa05d49	199	struct nilfs_sysfs_dev_subgroups *ns_dev_subgroups;
65b4643d RK	200	};
65b4643d RK	201
65b4643d RK	202	#define THE_NILFS_FNS(bit, name) \
	203	static inline void set_nilfs_##name(struct the_nilfs *nilfs) \
	204	{ \
	205	set_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
	206	} \
	207	static inline void clear_nilfs_##name(struct the_nilfs *nilfs) \
	208	{ \
	209	clear_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
	210	} \
	211	static inline int nilfs_##name(struct the_nilfs *nilfs) \
	212	{ \
	213	return test_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
	214	}
	215
	216	THE_NILFS_FNS(INIT, init)
65b4643d	217	THE_NILFS_FNS(DISCONTINUED, discontinued)
1cf58fa8	218	THE_NILFS_FNS(GC_RUNNING, gc_running)
e605f0a7	219	THE_NILFS_FNS(SB_DIRTY, sb_dirty)
65b4643d	220
3b2ce58b RK	221	/*
	222	* Mount option operations
	223	*/
	224	#define nilfs_clear_opt(nilfs, opt) \
	225	do { (nilfs)->ns_mount_opt &= ~NILFS_MOUNT_##opt; } while (0)
	226	#define nilfs_set_opt(nilfs, opt) \
	227	do { (nilfs)->ns_mount_opt \|= NILFS_MOUNT_##opt; } while (0)
	228	#define nilfs_test_opt(nilfs, opt) ((nilfs)->ns_mount_opt & NILFS_MOUNT_##opt)
	229	#define nilfs_write_opt(nilfs, mask, opt) \
	230	do { (nilfs)->ns_mount_opt = \
	231	(((nilfs)->ns_mount_opt & ~NILFS_MOUNT_##mask) \| \
	232	NILFS_MOUNT_##opt); \
	233	} while (0)
	234
ba65ae47 RK	235	/**
	236	* struct nilfs_root - nilfs root object
	237	* @cno: checkpoint number
	238	* @rb_node: red-black tree node
	239	* @count: refcount of this structure
	240	* @nilfs: nilfs object
	241	* @ifile: inode file
ba65ae47	242	* @inodes_count: number of inodes
f5974c8f	243	* @blocks_count: number of blocks
a5a7332a VD	244	* @snapshot_kobj: /sys/fs/<nilfs>/<device>/mounted_snapshots/<snapshot>
a5a7332a VD	245	* @snapshot_kobj_unregister: completion state for kernel object
ba65ae47 RK	246	*/
	247	struct nilfs_root {
	248	__u64 cno;
	249	struct rb_node rb_node;
	250
	251	atomic_t count;
	252	struct the_nilfs *nilfs;
	253	struct inode *ifile;
	254
e5f7f848 VD	255	atomic64_t inodes_count;
e5f7f848 VD	256	atomic64_t blocks_count;
a5a7332a VD	257
	258	/* /sys/fs/<nilfs>/<device>/mounted_snapshots/<snapshot> */
	259	struct kobject snapshot_kobj;
	260	struct completion snapshot_kobj_unregister;
ba65ae47 RK	261	};
	262
	263	/* Special checkpoint number */
	264	#define NILFS_CPTREE_CURRENT_CNO 0
	265
e339ad31 RK	266	/* Minimum interval of periodical update of superblocks (in seconds) */
e339ad31 RK	267	#define NILFS_SB_FREQ 10
e339ad31	268
79efdd94 JS	269	static inline int nilfs_sb_need_update(struct the_nilfs *nilfs)
	270	{
	271	u64 t = get_seconds();
4ad364ca	272
caa05d49 VD	273	return t < nilfs->ns_sbwtime \|\|
caa05d49 VD	274	t > nilfs->ns_sbwtime + nilfs->ns_sb_update_freq;
79efdd94 JS	275	}
79efdd94 JS	276
b2ac86e1	277	static inline int nilfs_sb_will_flip(struct the_nilfs *nilfs)
79efdd94	278	{
b2ac86e1	279	int flip_bits = nilfs->ns_sbwcount & 0x0FL;
4ad364ca	280
b2ac86e1	281	return (flip_bits != 0x08 && flip_bits != 0x0F);
79efdd94 JS	282	}
79efdd94 JS	283
65b4643d	284	void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64);
348fe8da RK	285	struct the_nilfs alloc_nilfs(struct block_device bdev);
348fe8da RK	286	void destroy_nilfs(struct the_nilfs *nilfs);
f7545144 RK	287	int init_nilfs(struct the_nilfs nilfs, struct super_block sb, char *data);
f7545144 RK	288	int load_nilfs(struct the_nilfs nilfs, struct super_block sb);
4e33f9ea RK	289	unsigned long nilfs_nrsvsegs(struct the_nilfs *nilfs, unsigned long nsegs);
4e33f9ea RK	290	void nilfs_set_nsegments(struct the_nilfs *nilfs, unsigned long nsegs);
e902ec99	291	int nilfs_discard_segments(struct the_nilfs , __u64 , size_t);
65b4643d	292	int nilfs_count_free_blocks(struct the_nilfs , sector_t );
ba65ae47 RK	293	struct nilfs_root nilfs_lookup_root(struct the_nilfs nilfs, __u64 cno);
	294	struct nilfs_root nilfs_find_or_create_root(struct the_nilfs nilfs,
	295	__u64 cno);
	296	void nilfs_put_root(struct nilfs_root *root);
65b4643d	297	int nilfs_near_disk_full(struct the_nilfs *);
e339ad31 RK	298	void nilfs_fall_back_super_block(struct the_nilfs *);
e339ad31 RK	299	void nilfs_swap_super_block(struct the_nilfs *);
65b4643d RK	300
65b4643d RK	301
ba65ae47 RK	302	static inline void nilfs_get_root(struct nilfs_root *root)
	303	{
	304	atomic_inc(&root->count);
	305	}
	306
a057d2c0 RK	307	static inline int nilfs_valid_fs(struct the_nilfs *nilfs)
a057d2c0 RK	308	{
0c6c44cb	309	unsigned int valid_fs;
a057d2c0 RK	310
	311	down_read(&nilfs->ns_sem);
	312	valid_fs = (nilfs->ns_mount_state & NILFS_VALID_FS);
	313	up_read(&nilfs->ns_sem);
	314	return valid_fs;
	315	}
	316
65b4643d RK	317	static inline void
	318	nilfs_get_segment_range(struct the_nilfs *nilfs, __u64 segnum,
	319	sector_t seg_start, sector_t seg_end)
	320	{
	321	seg_start = (sector_t)nilfs->ns_blocks_per_segment segnum;
	322	seg_end = seg_start + nilfs->ns_blocks_per_segment - 1;
	323	if (segnum == 0)
	324	*seg_start = nilfs->ns_first_data_block;
	325	}
	326
	327	static inline sector_t
	328	nilfs_get_segment_start_blocknr(struct the_nilfs *nilfs, __u64 segnum)
	329	{
	330	return (segnum == 0) ? nilfs->ns_first_data_block :
	331	(sector_t)nilfs->ns_blocks_per_segment * segnum;
	332	}
	333
	334	static inline __u64
	335	nilfs_get_segnum_of_block(struct the_nilfs *nilfs, sector_t blocknr)
	336	{
	337	sector_t segnum = blocknr;
	338
	339	sector_div(segnum, nilfs->ns_blocks_per_segment);
	340	return segnum;
	341	}
	342
	343	static inline void
	344	nilfs_terminate_segment(struct the_nilfs *nilfs, sector_t seg_start,
	345	sector_t seg_end)
	346	{
	347	/* terminate the current full segment (used in case of I/O-error) */
	348	nilfs->ns_pseg_offset = seg_end - seg_start + 1;
	349	}
	350
	351	static inline void nilfs_shift_to_next_segment(struct the_nilfs *nilfs)
	352	{
	353	/* move forward with a full segment */
	354	nilfs->ns_segnum = nilfs->ns_nextnum;
	355	nilfs->ns_pseg_offset = 0;
	356	nilfs->ns_seg_seq++;
	357	}
	358
	359	static inline __u64 nilfs_last_cno(struct the_nilfs *nilfs)
	360	{
	361	__u64 cno;
	362
	363	spin_lock(&nilfs->ns_last_segment_lock);
	364	cno = nilfs->ns_last_cno;
	365	spin_unlock(&nilfs->ns_last_segment_lock);
	366	return cno;
	367	}
	368
cece5520 RK	369	static inline int nilfs_segment_is_active(struct the_nilfs *nilfs, __u64 n)
	370	{
	371	return n == nilfs->ns_segnum \|\| n == nilfs->ns_nextnum;
	372	}
	373
e2c7617a AR	374	static inline int nilfs_flush_device(struct the_nilfs *nilfs)
	375	{
	376	int err;
	377
	378	if (!nilfs_test_opt(nilfs, BARRIER) \|\| nilfs->ns_flushed_device)
	379	return 0;
	380
	381	nilfs->ns_flushed_device = 1;
	382	/*
	383	* the store to ns_flushed_device must not be reordered after
	384	* blkdev_issue_flush().
	385	*/
	386	smp_wmb();
	387
	388	err = blkdev_issue_flush(nilfs->ns_bdev, GFP_KERNEL, NULL);
	389	if (err != -EIO)
	390	err = 0;
	391	return err;
	392	}
	393
65b4643d	394	#endif /* _THE_NILFS_H */