[linux.git] / fs / nilfs2 / dat.c

/*
 * dat.c - NILFS disk address translation.
 *
 * Copyright (C) 2006-2008 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Written by Koji Sato <[email protected]>.
 */

#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/string.h>
#include <linux/errno.h>
#include "nilfs.h"
#include "mdt.h"
#include "alloc.h"
#include "dat.h"


#define NILFS_CNO_MIN	((__u64)1)
#define NILFS_CNO_MAX	(~(__u64)0)

struct nilfs_dat_info {
	struct nilfs_mdt_info mi;
	struct nilfs_palloc_cache palloc_cache;
};

static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
{
	return (struct nilfs_dat_info *)NILFS_MDT(dat);
}

static int nilfs_dat_prepare_entry(struct inode *dat,
				   struct nilfs_palloc_req *req, int create)
{
	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
					    create, &req->pr_entry_bh);
}

static void nilfs_dat_commit_entry(struct inode *dat,
				   struct nilfs_palloc_req *req)
{
	nilfs_mdt_mark_buffer_dirty(req->pr_entry_bh);
	nilfs_mdt_mark_dirty(dat);
	brelse(req->pr_entry_bh);
}

static void nilfs_dat_abort_entry(struct inode *dat,
				  struct nilfs_palloc_req *req)
{
	brelse(req->pr_entry_bh);
}

int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
{
	int ret;

	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
	if (ret < 0)
		return ret;

	ret = nilfs_dat_prepare_entry(dat, req, 1);
	if (ret < 0)
		nilfs_palloc_abort_alloc_entry(dat, req);

	return ret;
}

void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
{
	struct nilfs_dat_entry *entry;
	void *kaddr;

	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
					     req->pr_entry_bh, kaddr);
	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
	entry->de_blocknr = cpu_to_le64(0);
	kunmap_atomic(kaddr, KM_USER0);

	nilfs_palloc_commit_alloc_entry(dat, req);
	nilfs_dat_commit_entry(dat, req);
}

void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
{
	nilfs_dat_abort_entry(dat, req);
	nilfs_palloc_abort_alloc_entry(dat, req);
}

void nilfs_dat_commit_free(struct inode *dat, struct nilfs_palloc_req *req)
{
	struct nilfs_dat_entry *entry;
	void *kaddr;

	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
					     req->pr_entry_bh, kaddr);
	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
	entry->de_blocknr = cpu_to_le64(0);
	kunmap_atomic(kaddr, KM_USER0);

	nilfs_dat_commit_entry(dat, req);
	nilfs_palloc_commit_free_entry(dat, req);
}

int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
{
	int ret;

	ret = nilfs_dat_prepare_entry(dat, req, 0);
	WARN_ON(ret == -ENOENT);
	return ret;
}

void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
			    sector_t blocknr)
{
	struct nilfs_dat_entry *entry;
	void *kaddr;

	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
					     req->pr_entry_bh, kaddr);
	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
	entry->de_blocknr = cpu_to_le64(blocknr);
	kunmap_atomic(kaddr, KM_USER0);

	nilfs_dat_commit_entry(dat, req);
}

int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
{
	struct nilfs_dat_entry *entry;
	__u64 start;
	sector_t blocknr;
	void *kaddr;
	int ret;

	ret = nilfs_dat_prepare_entry(dat, req, 0);
	if (ret < 0) {
		WARN_ON(ret == -ENOENT);
		return ret;
	}

	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
					     req->pr_entry_bh, kaddr);
	start = le64_to_cpu(entry->de_start);
	blocknr = le64_to_cpu(entry->de_blocknr);
	kunmap_atomic(kaddr, KM_USER0);

	if (blocknr == 0) {
		ret = nilfs_palloc_prepare_free_entry(dat, req);
		if (ret < 0) {
			nilfs_dat_abort_entry(dat, req);
			return ret;
		}
	}

	return 0;
}

void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
			  int dead)
{
	struct nilfs_dat_entry *entry;
	__u64 start, end;
	sector_t blocknr;
	void *kaddr;

	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
					     req->pr_entry_bh, kaddr);
	end = start = le64_to_cpu(entry->de_start);
	if (!dead) {
		end = nilfs_mdt_cno(dat);
		WARN_ON(start > end);
	}
	entry->de_end = cpu_to_le64(end);
	blocknr = le64_to_cpu(entry->de_blocknr);
	kunmap_atomic(kaddr, KM_USER0);

	if (blocknr == 0)
		nilfs_dat_commit_free(dat, req);
	else
		nilfs_dat_commit_entry(dat, req);
}

void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
{
	struct nilfs_dat_entry *entry;
	__u64 start;
	sector_t blocknr;
	void *kaddr;

	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
					     req->pr_entry_bh, kaddr);
	start = le64_to_cpu(entry->de_start);
	blocknr = le64_to_cpu(entry->de_blocknr);
	kunmap_atomic(kaddr, KM_USER0);

	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
		nilfs_palloc_abort_free_entry(dat, req);
	nilfs_dat_abort_entry(dat, req);
}

int nilfs_dat_prepare_update(struct inode *dat,
			     struct nilfs_palloc_req *oldreq,
			     struct nilfs_palloc_req *newreq)
{
	int ret;

	ret = nilfs_dat_prepare_end(dat, oldreq);
	if (!ret) {
		ret = nilfs_dat_prepare_alloc(dat, newreq);
		if (ret < 0)
			nilfs_dat_abort_end(dat, oldreq);
	}
	return ret;
}

void nilfs_dat_commit_update(struct inode *dat,
			     struct nilfs_palloc_req *oldreq,
			     struct nilfs_palloc_req *newreq, int dead)
{
	nilfs_dat_commit_end(dat, oldreq, dead);
	nilfs_dat_commit_alloc(dat, newreq);
}

void nilfs_dat_abort_update(struct inode *dat,
			    struct nilfs_palloc_req *oldreq,
			    struct nilfs_palloc_req *newreq)
{
	nilfs_dat_abort_end(dat, oldreq);
	nilfs_dat_abort_alloc(dat, newreq);
}

/**
 * nilfs_dat_mark_dirty -
 * @dat: DAT file inode
 * @vblocknr: virtual block number
 *
 * Description:
 *
 * Return Value: On success, 0 is returned. On error, one of the following
 * negative error codes is returned.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 */
int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
{
	struct nilfs_palloc_req req;
	int ret;

	req.pr_entry_nr = vblocknr;
	ret = nilfs_dat_prepare_entry(dat, &req, 0);
	if (ret == 0)
		nilfs_dat_commit_entry(dat, &req);
	return ret;
}

/**
 * nilfs_dat_freev - free virtual block numbers
 * @dat: DAT file inode
 * @vblocknrs: array of virtual block numbers
 * @nitems: number of virtual block numbers
 *
 * Description: nilfs_dat_freev() frees the virtual block numbers specified by
 * @vblocknrs and @nitems.
 *
 * Return Value: On success, 0 is returned. On error, one of the following
 * negative error codes is returned.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-ENOENT - The virtual block number have not been allocated.
 */
int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
{
	return nilfs_palloc_freev(dat, vblocknrs, nitems);
}

/**
 * nilfs_dat_move - change a block number
 * @dat: DAT file inode
 * @vblocknr: virtual block number
 * @blocknr: block number
 *
 * Description: nilfs_dat_move() changes the block number associated with
 * @vblocknr to @blocknr.
 *
 * Return Value: On success, 0 is returned. On error, one of the following
 * negative error codes is returned.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 */
int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
{
	struct buffer_head *entry_bh;
	struct nilfs_dat_entry *entry;
	void *kaddr;
	int ret;

	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
	if (ret < 0)
		return ret;
	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
		printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
		       (unsigned long long)vblocknr,
		       (unsigned long long)le64_to_cpu(entry->de_start),
		       (unsigned long long)le64_to_cpu(entry->de_end));
		kunmap_atomic(kaddr, KM_USER0);
		brelse(entry_bh);
		return -EINVAL;
	}
	WARN_ON(blocknr == 0);
	entry->de_blocknr = cpu_to_le64(blocknr);
	kunmap_atomic(kaddr, KM_USER0);

	nilfs_mdt_mark_buffer_dirty(entry_bh);
	nilfs_mdt_mark_dirty(dat);

	brelse(entry_bh);

	return 0;
}

/**
 * nilfs_dat_translate - translate a virtual block number to a block number
 * @dat: DAT file inode
 * @vblocknr: virtual block number
 * @blocknrp: pointer to a block number
 *
 * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
 * to the corresponding block number.
 *
 * Return Value: On success, 0 is returned and the block number associated
 * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
 * of the following negative error codes is returned.
 *
 * %-EIO - I/O error.
 *
 * %-ENOMEM - Insufficient amount of memory available.
 *
 * %-ENOENT - A block number associated with @vblocknr does not exist.
 */
int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
{
	struct buffer_head *entry_bh;
	struct nilfs_dat_entry *entry;
	sector_t blocknr;
	void *kaddr;
	int ret;

	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
	if (ret < 0)
		return ret;

	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
	blocknr = le64_to_cpu(entry->de_blocknr);
	if (blocknr == 0) {
		ret = -ENOENT;
		goto out;
	}
	*blocknrp = blocknr;

 out:
	kunmap_atomic(kaddr, KM_USER0);
	brelse(entry_bh);
	return ret;
}

ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz,
			    size_t nvi)
{
	struct buffer_head *entry_bh;
	struct nilfs_dat_entry *entry;
	struct nilfs_vinfo *vinfo = buf;
	__u64 first, last;
	void *kaddr;
	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
	int i, j, n, ret;

	for (i = 0; i < nvi; i += n) {
		ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
						   0, &entry_bh);
		if (ret < 0)
			return ret;
		kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
		/* last virtual block number in this block */
		first = vinfo->vi_vblocknr;
		do_div(first, entries_per_block);
		first *= entries_per_block;
		last = first + entries_per_block - 1;
		for (j = i, n = 0;
		     j < nvi && vinfo->vi_vblocknr >= first &&
			     vinfo->vi_vblocknr <= last;
		     j++, n++, vinfo = (void *)vinfo + visz) {
			entry = nilfs_palloc_block_get_entry(
				dat, vinfo->vi_vblocknr, entry_bh, kaddr);
			vinfo->vi_start = le64_to_cpu(entry->de_start);
			vinfo->vi_end = le64_to_cpu(entry->de_end);
			vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
		}
		kunmap_atomic(kaddr, KM_USER0);
		brelse(entry_bh);
	}

	return nvi;
}

/**
 * nilfs_dat_read - read dat inode
 * @dat: dat inode
 * @raw_inode: on-disk dat inode
 */
int nilfs_dat_read(struct inode *dat, struct nilfs_inode *raw_inode)
{
	return nilfs_read_inode_common(dat, raw_inode);
}

/**
 * nilfs_dat_new - create dat file
 * @nilfs: nilfs object
 * @entry_size: size of a dat entry
 */
struct inode *nilfs_dat_new(struct the_nilfs *nilfs, size_t entry_size)
{
	static struct lock_class_key dat_lock_key;
	struct inode *dat;
	struct nilfs_dat_info *di;
	int err;

	dat = nilfs_mdt_new(nilfs, NULL, NILFS_DAT_INO, sizeof(*di));
	if (dat) {
		err = nilfs_palloc_init_blockgroup(dat, entry_size);
		if (unlikely(err)) {
			nilfs_mdt_destroy(dat);
			return NULL;
		}

		di = NILFS_DAT_I(dat);
		lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
		nilfs_palloc_setup_cache(dat, &di->palloc_cache);
	}
	return dat;
}
Commit	Line	Data
a17564f5 KS	1	/*
	2	* dat.c - NILFS disk address translation.
	3	*
	4	* Copyright (C) 2006-2008 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	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*
	20	* Written by Koji Sato <[email protected]>.
	21	*/
	22
	23	#include <linux/types.h>
	24	#include <linux/buffer_head.h>
	25	#include <linux/string.h>
	26	#include <linux/errno.h>
	27	#include "nilfs.h"
	28	#include "mdt.h"
	29	#include "alloc.h"
	30	#include "dat.h"
	31
	32
	33	#define NILFS_CNO_MIN ((__u64)1)
	34	#define NILFS_CNO_MAX (~(__u64)0)
	35
8908b2f7 RK	36	struct nilfs_dat_info {
	37	struct nilfs_mdt_info mi;
	38	struct nilfs_palloc_cache palloc_cache;
	39	};
	40
	41	static inline struct nilfs_dat_info NILFS_DAT_I(struct inode dat)
	42	{
	43	return (struct nilfs_dat_info *)NILFS_MDT(dat);
	44	}
	45
a17564f5 KS	46	static int nilfs_dat_prepare_entry(struct inode *dat,
	47	struct nilfs_palloc_req *req, int create)
	48	{
	49	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
	50	create, &req->pr_entry_bh);
	51	}
	52
	53	static void nilfs_dat_commit_entry(struct inode *dat,
	54	struct nilfs_palloc_req *req)
	55	{
	56	nilfs_mdt_mark_buffer_dirty(req->pr_entry_bh);
	57	nilfs_mdt_mark_dirty(dat);
	58	brelse(req->pr_entry_bh);
	59	}
	60
	61	static void nilfs_dat_abort_entry(struct inode *dat,
	62	struct nilfs_palloc_req *req)
	63	{
	64	brelse(req->pr_entry_bh);
	65	}
	66
	67	int nilfs_dat_prepare_alloc(struct inode dat, struct nilfs_palloc_req req)
	68	{
	69	int ret;
	70
	71	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
	72	if (ret < 0)
	73	return ret;
	74
	75	ret = nilfs_dat_prepare_entry(dat, req, 1);
	76	if (ret < 0)
	77	nilfs_palloc_abort_alloc_entry(dat, req);
	78
	79	return ret;
	80	}
	81
	82	void nilfs_dat_commit_alloc(struct inode dat, struct nilfs_palloc_req req)
	83	{
	84	struct nilfs_dat_entry *entry;
	85	void *kaddr;
	86
	87	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	88	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	89	req->pr_entry_bh, kaddr);
	90	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
	91	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
	92	entry->de_blocknr = cpu_to_le64(0);
	93	kunmap_atomic(kaddr, KM_USER0);
	94
	95	nilfs_palloc_commit_alloc_entry(dat, req);
	96	nilfs_dat_commit_entry(dat, req);
	97	}
	98
	99	void nilfs_dat_abort_alloc(struct inode dat, struct nilfs_palloc_req req)
	100	{
	101	nilfs_dat_abort_entry(dat, req);
	102	nilfs_palloc_abort_alloc_entry(dat, req);
	103	}
	104
a17564f5 KS	105	void nilfs_dat_commit_free(struct inode dat, struct nilfs_palloc_req req)
	106	{
	107	struct nilfs_dat_entry *entry;
	108	void *kaddr;
	109
	110	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	111	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	112	req->pr_entry_bh, kaddr);
	113	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
	114	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
	115	entry->de_blocknr = cpu_to_le64(0);
	116	kunmap_atomic(kaddr, KM_USER0);
	117
	118	nilfs_dat_commit_entry(dat, req);
	119	nilfs_palloc_commit_free_entry(dat, req);
	120	}
	121
a17564f5 KS	122	int nilfs_dat_prepare_start(struct inode dat, struct nilfs_palloc_req req)
	123	{
	124	int ret;
	125
	126	ret = nilfs_dat_prepare_entry(dat, req, 0);
1f5abe7e	127	WARN_ON(ret == -ENOENT);
a17564f5 KS	128	return ret;
	129	}
	130
	131	void nilfs_dat_commit_start(struct inode dat, struct nilfs_palloc_req req,
	132	sector_t blocknr)
	133	{
	134	struct nilfs_dat_entry *entry;
	135	void *kaddr;
	136
	137	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	138	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	139	req->pr_entry_bh, kaddr);
	140	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
a17564f5 KS	141	entry->de_blocknr = cpu_to_le64(blocknr);
	142	kunmap_atomic(kaddr, KM_USER0);
	143
	144	nilfs_dat_commit_entry(dat, req);
	145	}
	146
a17564f5 KS	147	int nilfs_dat_prepare_end(struct inode dat, struct nilfs_palloc_req req)
	148	{
	149	struct nilfs_dat_entry *entry;
	150	__u64 start;
	151	sector_t blocknr;
	152	void *kaddr;
	153	int ret;
	154
	155	ret = nilfs_dat_prepare_entry(dat, req, 0);
	156	if (ret < 0) {
1f5abe7e	157	WARN_ON(ret == -ENOENT);
a17564f5 KS	158	return ret;
	159	}
	160
	161	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	162	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	163	req->pr_entry_bh, kaddr);
	164	start = le64_to_cpu(entry->de_start);
	165	blocknr = le64_to_cpu(entry->de_blocknr);
	166	kunmap_atomic(kaddr, KM_USER0);
	167
	168	if (blocknr == 0) {
	169	ret = nilfs_palloc_prepare_free_entry(dat, req);
	170	if (ret < 0) {
	171	nilfs_dat_abort_entry(dat, req);
	172	return ret;
	173	}
	174	}
	175
	176	return 0;
	177	}
	178
	179	void nilfs_dat_commit_end(struct inode dat, struct nilfs_palloc_req req,
	180	int dead)
	181	{
	182	struct nilfs_dat_entry *entry;
	183	__u64 start, end;
	184	sector_t blocknr;
	185	void *kaddr;
	186
	187	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	188	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	189	req->pr_entry_bh, kaddr);
	190	end = start = le64_to_cpu(entry->de_start);
	191	if (!dead) {
	192	end = nilfs_mdt_cno(dat);
1f5abe7e	193	WARN_ON(start > end);
a17564f5 KS	194	}
	195	entry->de_end = cpu_to_le64(end);
	196	blocknr = le64_to_cpu(entry->de_blocknr);
	197	kunmap_atomic(kaddr, KM_USER0);
	198
	199	if (blocknr == 0)
	200	nilfs_dat_commit_free(dat, req);
	201	else
	202	nilfs_dat_commit_entry(dat, req);
	203	}
	204
	205	void nilfs_dat_abort_end(struct inode dat, struct nilfs_palloc_req req)
	206	{
	207	struct nilfs_dat_entry *entry;
	208	__u64 start;
	209	sector_t blocknr;
	210	void *kaddr;
	211
	212	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	213	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	214	req->pr_entry_bh, kaddr);
	215	start = le64_to_cpu(entry->de_start);
	216	blocknr = le64_to_cpu(entry->de_blocknr);
	217	kunmap_atomic(kaddr, KM_USER0);
	218
	219	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
	220	nilfs_palloc_abort_free_entry(dat, req);
	221	nilfs_dat_abort_entry(dat, req);
	222	}
	223
bd8169ef RK	224	int nilfs_dat_prepare_update(struct inode *dat,
	225	struct nilfs_palloc_req *oldreq,
	226	struct nilfs_palloc_req *newreq)
	227	{
	228	int ret;
	229
	230	ret = nilfs_dat_prepare_end(dat, oldreq);
	231	if (!ret) {
	232	ret = nilfs_dat_prepare_alloc(dat, newreq);
	233	if (ret < 0)
	234	nilfs_dat_abort_end(dat, oldreq);
	235	}
	236	return ret;
	237	}
	238
	239	void nilfs_dat_commit_update(struct inode *dat,
	240	struct nilfs_palloc_req *oldreq,
	241	struct nilfs_palloc_req *newreq, int dead)
	242	{
	243	nilfs_dat_commit_end(dat, oldreq, dead);
	244	nilfs_dat_commit_alloc(dat, newreq);
	245	}
	246
	247	void nilfs_dat_abort_update(struct inode *dat,
	248	struct nilfs_palloc_req *oldreq,
	249	struct nilfs_palloc_req *newreq)
	250	{
	251	nilfs_dat_abort_end(dat, oldreq);
	252	nilfs_dat_abort_alloc(dat, newreq);
	253	}
	254
a17564f5 KS	255	/**
	256	* nilfs_dat_mark_dirty -
	257	* @dat: DAT file inode
	258	* @vblocknr: virtual block number
	259	*
	260	* Description:
	261	*
	262	* Return Value: On success, 0 is returned. On error, one of the following
	263	* negative error codes is returned.
	264	*
	265	* %-EIO - I/O error.
	266	*
	267	* %-ENOMEM - Insufficient amount of memory available.
	268	*/
	269	int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
	270	{
	271	struct nilfs_palloc_req req;
	272	int ret;
	273
	274	req.pr_entry_nr = vblocknr;
	275	ret = nilfs_dat_prepare_entry(dat, &req, 0);
	276	if (ret == 0)
	277	nilfs_dat_commit_entry(dat, &req);
	278	return ret;
	279	}
	280
	281	/**
	282	* nilfs_dat_freev - free virtual block numbers
	283	* @dat: DAT file inode
	284	* @vblocknrs: array of virtual block numbers
	285	* @nitems: number of virtual block numbers
	286	*
	287	* Description: nilfs_dat_freev() frees the virtual block numbers specified by
	288	* @vblocknrs and @nitems.
	289	*
	290	* Return Value: On success, 0 is returned. On error, one of the following
7a65004b	291	* negative error codes is returned.
a17564f5 KS	292	*
	293	* %-EIO - I/O error.
	294	*
	295	* %-ENOMEM - Insufficient amount of memory available.
	296	*
	297	* %-ENOENT - The virtual block number have not been allocated.
	298	*/
	299	int nilfs_dat_freev(struct inode dat, __u64 vblocknrs, size_t nitems)
	300	{
	301	return nilfs_palloc_freev(dat, vblocknrs, nitems);
	302	}
	303
	304	/**
	305	* nilfs_dat_move - change a block number
	306	* @dat: DAT file inode
	307	* @vblocknr: virtual block number
	308	* @blocknr: block number
	309	*
	310	* Description: nilfs_dat_move() changes the block number associated with
	311	* @vblocknr to @blocknr.
	312	*
	313	* Return Value: On success, 0 is returned. On error, one of the following
	314	* negative error codes is returned.
	315	*
	316	* %-EIO - I/O error.
	317	*
	318	* %-ENOMEM - Insufficient amount of memory available.
	319	*/
	320	int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
	321	{
	322	struct buffer_head *entry_bh;
	323	struct nilfs_dat_entry *entry;
	324	void *kaddr;
	325	int ret;
	326
	327	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
	328	if (ret < 0)
	329	return ret;
	330	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
	331	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
1f5abe7e	332	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
a17564f5 KS	333	printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
	334	(unsigned long long)vblocknr,
	335	(unsigned long long)le64_to_cpu(entry->de_start),
	336	(unsigned long long)le64_to_cpu(entry->de_end));
1f5abe7e RK	337	kunmap_atomic(kaddr, KM_USER0);
	338	brelse(entry_bh);
	339	return -EINVAL;
a17564f5	340	}
1f5abe7e	341	WARN_ON(blocknr == 0);
a17564f5 KS	342	entry->de_blocknr = cpu_to_le64(blocknr);
	343	kunmap_atomic(kaddr, KM_USER0);
	344
	345	nilfs_mdt_mark_buffer_dirty(entry_bh);
	346	nilfs_mdt_mark_dirty(dat);
	347
	348	brelse(entry_bh);
	349
	350	return 0;
	351	}
	352
	353	/**
	354	* nilfs_dat_translate - translate a virtual block number to a block number
	355	* @dat: DAT file inode
	356	* @vblocknr: virtual block number
	357	* @blocknrp: pointer to a block number
	358	*
	359	* Description: nilfs_dat_translate() maps the virtual block number @vblocknr
	360	* to the corresponding block number.
	361	*
	362	* Return Value: On success, 0 is returned and the block number associated
	363	* with @vblocknr is stored in the place pointed by @blocknrp. On error, one
	364	* of the following negative error codes is returned.
	365	*
	366	* %-EIO - I/O error.
	367	*
	368	* %-ENOMEM - Insufficient amount of memory available.
	369	*
	370	* %-ENOENT - A block number associated with @vblocknr does not exist.
	371	*/
	372	int nilfs_dat_translate(struct inode dat, __u64 vblocknr, sector_t blocknrp)
	373	{
	374	struct buffer_head *entry_bh;
	375	struct nilfs_dat_entry *entry;
	376	sector_t blocknr;
	377	void *kaddr;
	378	int ret;
	379
	380	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
	381	if (ret < 0)
	382	return ret;
	383
	384	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
	385	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
	386	blocknr = le64_to_cpu(entry->de_blocknr);
	387	if (blocknr == 0) {
	388	ret = -ENOENT;
	389	goto out;
	390	}
086d1764	391	*blocknrp = blocknr;
a17564f5 KS	392
	393	out:
	394	kunmap_atomic(kaddr, KM_USER0);
	395	brelse(entry_bh);
	396	return ret;
	397	}
	398
003ff182	399	ssize_t nilfs_dat_get_vinfo(struct inode dat, void buf, unsigned visz,
a17564f5 KS	400	size_t nvi)
	401	{
	402	struct buffer_head *entry_bh;
	403	struct nilfs_dat_entry *entry;
003ff182	404	struct nilfs_vinfo *vinfo = buf;
a17564f5 KS	405	__u64 first, last;
	406	void *kaddr;
	407	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
	408	int i, j, n, ret;
	409
	410	for (i = 0; i < nvi; i += n) {
003ff182	411	ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
a17564f5 KS	412	0, &entry_bh);
	413	if (ret < 0)
	414	return ret;
	415	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
	416	/* last virtual block number in this block */
003ff182	417	first = vinfo->vi_vblocknr;
a17564f5 KS	418	do_div(first, entries_per_block);
	419	first *= entries_per_block;
	420	last = first + entries_per_block - 1;
	421	for (j = i, n = 0;
003ff182 RK	422	j < nvi && vinfo->vi_vblocknr >= first &&
	423	vinfo->vi_vblocknr <= last;
	424	j++, n++, vinfo = (void *)vinfo + visz) {
a17564f5	425	entry = nilfs_palloc_block_get_entry(
003ff182 RK	426	dat, vinfo->vi_vblocknr, entry_bh, kaddr);
	427	vinfo->vi_start = le64_to_cpu(entry->de_start);
	428	vinfo->vi_end = le64_to_cpu(entry->de_end);
	429	vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
a17564f5 KS	430	}
	431	kunmap_atomic(kaddr, KM_USER0);
	432	brelse(entry_bh);
	433	}
	434
	435	return nvi;
	436	}
79739565	437
8707df38 RK	438	/**
	439	* nilfs_dat_read - read dat inode
	440	* @dat: dat inode
	441	* @raw_inode: on-disk dat inode
	442	*/
	443	int nilfs_dat_read(struct inode dat, struct nilfs_inode raw_inode)
	444	{
	445	return nilfs_read_inode_common(dat, raw_inode);
	446	}
	447
79739565 RK	448	/**
	449	* nilfs_dat_new - create dat file
	450	* @nilfs: nilfs object
	451	* @entry_size: size of a dat entry
	452	*/
	453	struct inode nilfs_dat_new(struct the_nilfs nilfs, size_t entry_size)
	454	{
	455	static struct lock_class_key dat_lock_key;
	456	struct inode *dat;
8908b2f7	457	struct nilfs_dat_info *di;
79739565 RK	458	int err;
79739565 RK	459
8908b2f7	460	dat = nilfs_mdt_new(nilfs, NULL, NILFS_DAT_INO, sizeof(*di));
79739565 RK	461	if (dat) {
	462	err = nilfs_palloc_init_blockgroup(dat, entry_size);
	463	if (unlikely(err)) {
	464	nilfs_mdt_destroy(dat);
	465	return NULL;
	466	}
8908b2f7 RK	467
	468	di = NILFS_DAT_I(dat);
	469	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
	470	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
79739565 RK	471	}
	472	return dat;
	473	}