[net-next-2.6.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 <koji@osrg.net>.
 */

#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)

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
 * nagative 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;
	}
	if (blocknrp != NULL)
		*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_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;
	int err;

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