[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)

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);
}

void nilfs_dat_abort_free(struct inode *dat, struct nilfs_palloc_req *req)
{
	nilfs_dat_abort_entry(dat, req);
	nilfs_palloc_abort_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));
	if (entry->de_blocknr != cpu_to_le64(0) ||
	    entry->de_end != cpu_to_le64(NILFS_CNO_MAX)) {
		printk(KERN_CRIT
		       "%s: vbn = %llu, start = %llu, end = %llu, pbn = %llu\n",
		       __func__, (unsigned long long)req->pr_entry_nr,
		       (unsigned long long)le64_to_cpu(entry->de_start),
		       (unsigned long long)le64_to_cpu(entry->de_end),
		       (unsigned long long)le64_to_cpu(entry->de_blocknr));
	}
	entry->de_blocknr = cpu_to_le64(blocknr);
	kunmap_atomic(kaddr, KM_USER0);

	nilfs_dat_commit_entry(dat, req);
}

void nilfs_dat_abort_start(struct inode *dat, struct nilfs_palloc_req *req)
{
	nilfs_dat_abort_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);
}

/**
 * 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;
}
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
	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
	112	void nilfs_dat_abort_free(struct inode dat, struct nilfs_palloc_req req)
	113	{
	114	nilfs_dat_abort_entry(dat, req);
	115	nilfs_palloc_abort_free_entry(dat, req);
	116	}
	117
	118	int nilfs_dat_prepare_start(struct inode dat, struct nilfs_palloc_req req)
	119	{
	120	int ret;
	121
	122	ret = nilfs_dat_prepare_entry(dat, req, 0);
1f5abe7e	123	WARN_ON(ret == -ENOENT);
a17564f5 KS	124	return ret;
	125	}
	126
	127	void nilfs_dat_commit_start(struct inode dat, struct nilfs_palloc_req req,
	128	sector_t blocknr)
	129	{
	130	struct nilfs_dat_entry *entry;
	131	void *kaddr;
	132
	133	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	134	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	135	req->pr_entry_bh, kaddr);
	136	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
	137	if (entry->de_blocknr != cpu_to_le64(0) \|\|
	138	entry->de_end != cpu_to_le64(NILFS_CNO_MAX)) {
	139	printk(KERN_CRIT
	140	"%s: vbn = %llu, start = %llu, end = %llu, pbn = %llu\n",
	141	__func__, (unsigned long long)req->pr_entry_nr,
	142	(unsigned long long)le64_to_cpu(entry->de_start),
	143	(unsigned long long)le64_to_cpu(entry->de_end),
	144	(unsigned long long)le64_to_cpu(entry->de_blocknr));
a17564f5 KS	145	}
	146	entry->de_blocknr = cpu_to_le64(blocknr);
	147	kunmap_atomic(kaddr, KM_USER0);
	148
	149	nilfs_dat_commit_entry(dat, req);
	150	}
	151
	152	void nilfs_dat_abort_start(struct inode dat, struct nilfs_palloc_req req)
	153	{
	154	nilfs_dat_abort_entry(dat, req);
	155	}
	156
	157	int nilfs_dat_prepare_end(struct inode dat, struct nilfs_palloc_req req)
	158	{
	159	struct nilfs_dat_entry *entry;
	160	__u64 start;
	161	sector_t blocknr;
	162	void *kaddr;
	163	int ret;
	164
	165	ret = nilfs_dat_prepare_entry(dat, req, 0);
	166	if (ret < 0) {
1f5abe7e	167	WARN_ON(ret == -ENOENT);
a17564f5 KS	168	return ret;
	169	}
	170
	171	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	172	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	173	req->pr_entry_bh, kaddr);
	174	start = le64_to_cpu(entry->de_start);
	175	blocknr = le64_to_cpu(entry->de_blocknr);
	176	kunmap_atomic(kaddr, KM_USER0);
	177
	178	if (blocknr == 0) {
	179	ret = nilfs_palloc_prepare_free_entry(dat, req);
	180	if (ret < 0) {
	181	nilfs_dat_abort_entry(dat, req);
	182	return ret;
	183	}
	184	}
	185
	186	return 0;
	187	}
	188
	189	void nilfs_dat_commit_end(struct inode dat, struct nilfs_palloc_req req,
	190	int dead)
	191	{
	192	struct nilfs_dat_entry *entry;
	193	__u64 start, end;
	194	sector_t blocknr;
	195	void *kaddr;
	196
	197	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	198	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	199	req->pr_entry_bh, kaddr);
	200	end = start = le64_to_cpu(entry->de_start);
	201	if (!dead) {
	202	end = nilfs_mdt_cno(dat);
1f5abe7e	203	WARN_ON(start > end);
a17564f5 KS	204	}
	205	entry->de_end = cpu_to_le64(end);
	206	blocknr = le64_to_cpu(entry->de_blocknr);
	207	kunmap_atomic(kaddr, KM_USER0);
	208
	209	if (blocknr == 0)
	210	nilfs_dat_commit_free(dat, req);
	211	else
	212	nilfs_dat_commit_entry(dat, req);
	213	}
	214
	215	void nilfs_dat_abort_end(struct inode dat, struct nilfs_palloc_req req)
	216	{
	217	struct nilfs_dat_entry *entry;
	218	__u64 start;
	219	sector_t blocknr;
	220	void *kaddr;
	221
	222	kaddr = kmap_atomic(req->pr_entry_bh->b_page, KM_USER0);
	223	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	224	req->pr_entry_bh, kaddr);
	225	start = le64_to_cpu(entry->de_start);
	226	blocknr = le64_to_cpu(entry->de_blocknr);
	227	kunmap_atomic(kaddr, KM_USER0);
	228
	229	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
	230	nilfs_palloc_abort_free_entry(dat, req);
	231	nilfs_dat_abort_entry(dat, req);
	232	}
	233
	234	/**
	235	* nilfs_dat_mark_dirty -
	236	* @dat: DAT file inode
	237	* @vblocknr: virtual block number
	238	*
	239	* Description:
	240	*
	241	* Return Value: On success, 0 is returned. On error, one of the following
	242	* negative error codes is returned.
	243	*
	244	* %-EIO - I/O error.
	245	*
	246	* %-ENOMEM - Insufficient amount of memory available.
	247	*/
	248	int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
	249	{
	250	struct nilfs_palloc_req req;
	251	int ret;
	252
	253	req.pr_entry_nr = vblocknr;
	254	ret = nilfs_dat_prepare_entry(dat, &req, 0);
	255	if (ret == 0)
	256	nilfs_dat_commit_entry(dat, &req);
	257	return ret;
	258	}
	259
	260	/**
	261	* nilfs_dat_freev - free virtual block numbers
	262	* @dat: DAT file inode
	263	* @vblocknrs: array of virtual block numbers
	264	* @nitems: number of virtual block numbers
	265	*
	266	* Description: nilfs_dat_freev() frees the virtual block numbers specified by
	267	* @vblocknrs and @nitems.
268	*
269	* Return Value: On success, 0 is returned. On error, one of the following
270	* nagative error codes is returned.
271	*
272	* %-EIO - I/O error.
273	*
274	* %-ENOMEM - Insufficient amount of memory available.
275	*
276	* %-ENOENT - The virtual block number have not been allocated.
277	*/
278	int nilfs_dat_freev(struct inode dat, __u64 vblocknrs, size_t nitems)
279	{
280	return nilfs_palloc_freev(dat, vblocknrs, nitems);
281	}
282
283	/**
284	* nilfs_dat_move - change a block number
285	* @dat: DAT file inode
286	* @vblocknr: virtual block number
287	* @blocknr: block number
288	*
289	* Description: nilfs_dat_move() changes the block number associated with
290	* @vblocknr to @blocknr.
291	*
292	* Return Value: On success, 0 is returned. On error, one of the following
293	* negative error codes is returned.
294	*
295	* %-EIO - I/O error.
296	*
297	* %-ENOMEM - Insufficient amount of memory available.
298	*/
299	int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
300	{
301	struct buffer_head *entry_bh;
302	struct nilfs_dat_entry *entry;
303	void *kaddr;
304	int ret;
305
306	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
307	if (ret < 0)
308	return ret;
309	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
310	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
1f5abe7e	311	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
a17564f5 KS	312	printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
	313	(unsigned long long)vblocknr,
	314	(unsigned long long)le64_to_cpu(entry->de_start),
	315	(unsigned long long)le64_to_cpu(entry->de_end));
1f5abe7e RK	316	kunmap_atomic(kaddr, KM_USER0);
	317	brelse(entry_bh);
	318	return -EINVAL;
a17564f5	319	}
1f5abe7e	320	WARN_ON(blocknr == 0);
a17564f5 KS	321	entry->de_blocknr = cpu_to_le64(blocknr);
	322	kunmap_atomic(kaddr, KM_USER0);
	323
	324	nilfs_mdt_mark_buffer_dirty(entry_bh);
	325	nilfs_mdt_mark_dirty(dat);
	326
	327	brelse(entry_bh);
	328
	329	return 0;
	330	}
	331
	332	/**
	333	* nilfs_dat_translate - translate a virtual block number to a block number
	334	* @dat: DAT file inode
	335	* @vblocknr: virtual block number
	336	* @blocknrp: pointer to a block number
	337	*
	338	* Description: nilfs_dat_translate() maps the virtual block number @vblocknr
	339	* to the corresponding block number.
	340	*
	341	* Return Value: On success, 0 is returned and the block number associated
	342	* with @vblocknr is stored in the place pointed by @blocknrp. On error, one
	343	* of the following negative error codes is returned.
	344	*
	345	* %-EIO - I/O error.
	346	*
	347	* %-ENOMEM - Insufficient amount of memory available.
	348	*
	349	* %-ENOENT - A block number associated with @vblocknr does not exist.
	350	*/
	351	int nilfs_dat_translate(struct inode dat, __u64 vblocknr, sector_t blocknrp)
	352	{
	353	struct buffer_head *entry_bh;
	354	struct nilfs_dat_entry *entry;
	355	sector_t blocknr;
	356	void *kaddr;
	357	int ret;
	358
	359	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
	360	if (ret < 0)
	361	return ret;
	362
	363	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
	364	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
	365	blocknr = le64_to_cpu(entry->de_blocknr);
	366	if (blocknr == 0) {
	367	ret = -ENOENT;
	368	goto out;
	369	}
	370	if (blocknrp != NULL)
	371	*blocknrp = blocknr;
	372
	373	out:
	374	kunmap_atomic(kaddr, KM_USER0);
	375	brelse(entry_bh);
	376	return ret;
	377	}
	378
003ff182	379	ssize_t nilfs_dat_get_vinfo(struct inode dat, void buf, unsigned visz,
a17564f5 KS	380	size_t nvi)
	381	{
	382	struct buffer_head *entry_bh;
	383	struct nilfs_dat_entry *entry;
003ff182	384	struct nilfs_vinfo *vinfo = buf;
a17564f5 KS	385	__u64 first, last;
	386	void *kaddr;
	387	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
	388	int i, j, n, ret;
	389
	390	for (i = 0; i < nvi; i += n) {
003ff182	391	ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
a17564f5 KS	392	0, &entry_bh);
	393	if (ret < 0)
	394	return ret;
	395	kaddr = kmap_atomic(entry_bh->b_page, KM_USER0);
	396	/* last virtual block number in this block */
003ff182	397	first = vinfo->vi_vblocknr;
a17564f5 KS	398	do_div(first, entries_per_block);
	399	first *= entries_per_block;
	400	last = first + entries_per_block - 1;
	401	for (j = i, n = 0;
003ff182 RK	402	j < nvi && vinfo->vi_vblocknr >= first &&
	403	vinfo->vi_vblocknr <= last;
	404	j++, n++, vinfo = (void *)vinfo + visz) {
a17564f5	405	entry = nilfs_palloc_block_get_entry(
003ff182 RK	406	dat, vinfo->vi_vblocknr, entry_bh, kaddr);
	407	vinfo->vi_start = le64_to_cpu(entry->de_start);
	408	vinfo->vi_end = le64_to_cpu(entry->de_end);
	409	vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
a17564f5 KS	410	}
	411	kunmap_atomic(kaddr, KM_USER0);
	412	brelse(entry_bh);
	413	}
	414
	415	return nvi;
	416	}