[linux-2.6-block.git] / fs / nilfs2 / dat.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * dat.c - NILFS disk address translation.
 *
 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
 *
 * Written by Koji Sato.
 */

#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 - on-memory private data of DAT file
 * @mi: on-memory private data of metadata file
 * @palloc_cache: persistent object allocator cache of DAT file
 * @shadow: shadow map of DAT file
 */
struct nilfs_dat_info {
	struct nilfs_mdt_info mi;
	struct nilfs_palloc_cache palloc_cache;
	struct nilfs_shadow_map shadow;
};

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)
{
	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);
	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);

	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);
}

static 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);
	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);

	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);
	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);

	nilfs_dat_commit_entry(dat, req);
}

int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
{
	struct nilfs_dat_entry *entry;
	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);
	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
					     req->pr_entry_bh, kaddr);
	blocknr = le64_to_cpu(entry->de_blocknr);
	kunmap_atomic(kaddr);

	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);
	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);

	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);
	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);

	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;

	/*
	 * The given disk block number (blocknr) is not yet written to
	 * the device at this point.
	 *
	 * To prevent nilfs_dat_translate() from returning the
	 * uncommitted block number, this makes a copy of the entry
	 * buffer and redirects nilfs_dat_translate() to the copy.
	 */
	if (!buffer_nilfs_redirected(entry_bh)) {
		ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
		if (ret) {
			brelse(entry_bh);
			return ret;
		}
	}

	kaddr = kmap_atomic(entry_bh->b_page);
	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
		nilfs_msg(dat->i_sb, KERN_CRIT,
			  "%s: invalid vblocknr = %llu, [%llu, %llu)",
			  __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);
		brelse(entry_bh);
		return -EINVAL;
	}
	WARN_ON(blocknr == 0);
	entry->de_blocknr = cpu_to_le64(blocknr);
	kunmap_atomic(kaddr);

	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, *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;

	if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
		bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
		if (bh) {
			WARN_ON(!buffer_uptodate(bh));
			brelse(entry_bh);
			entry_bh = bh;
		}
	}

	kaddr = kmap_atomic(entry_bh->b_page);
	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);
	brelse(entry_bh);
	return ret;
}

ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned int 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);
		/* 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);
		brelse(entry_bh);
	}

	return nvi;
}

/**
 * nilfs_dat_read - read or get dat inode
 * @sb: super block instance
 * @entry_size: size of a dat entry
 * @raw_inode: on-disk dat inode
 * @inodep: buffer to store the inode
 */
int nilfs_dat_read(struct super_block *sb, size_t entry_size,
		   struct nilfs_inode *raw_inode, struct inode **inodep)
{
	static struct lock_class_key dat_lock_key;
	struct inode *dat;
	struct nilfs_dat_info *di;
	int err;

	if (entry_size > sb->s_blocksize) {
		nilfs_msg(sb, KERN_ERR, "too large DAT entry size: %zu bytes",
			  entry_size);
		return -EINVAL;
	} else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
		nilfs_msg(sb, KERN_ERR, "too small DAT entry size: %zu bytes",
			  entry_size);
		return -EINVAL;
	}

	dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
	if (unlikely(!dat))
		return -ENOMEM;
	if (!(dat->i_state & I_NEW))
		goto out;

	err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
	if (err)
		goto failed;

	err = nilfs_palloc_init_blockgroup(dat, entry_size);
	if (err)
		goto failed;

	di = NILFS_DAT_I(dat);
	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
	nilfs_mdt_setup_shadow_map(dat, &di->shadow);

	err = nilfs_read_inode_common(dat, raw_inode);
	if (err)
		goto failed;

	unlock_new_inode(dat);
 out:
	*inodep = dat;
	return 0;
 failed:
	iget_failed(dat);
	return err;
}
Commit	Line	Data
ae98043f	1	// SPDX-License-Identifier: GPL-2.0+
a17564f5 KS	2	/*
	3	* dat.c - NILFS disk address translation.
	4	*
	5	* Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
	6	*
4b420ab4	7	* Written by Koji Sato.
a17564f5 KS	8	*/
	9
	10	#include <linux/types.h>
	11	#include <linux/buffer_head.h>
	12	#include <linux/string.h>
	13	#include <linux/errno.h>
	14	#include "nilfs.h"
	15	#include "mdt.h"
	16	#include "alloc.h"
	17	#include "dat.h"
	18
	19
	20	#define NILFS_CNO_MIN ((__u64)1)
	21	#define NILFS_CNO_MAX (~(__u64)0)
	22
f5974c8f VD	23	/**
	24	* struct nilfs_dat_info - on-memory private data of DAT file
	25	* @mi: on-memory private data of metadata file
	26	* @palloc_cache: persistent object allocator cache of DAT file
	27	* @shadow: shadow map of DAT file
	28	*/
8908b2f7 RK	29	struct nilfs_dat_info {
	30	struct nilfs_mdt_info mi;
	31	struct nilfs_palloc_cache palloc_cache;
c1c1d709	32	struct nilfs_shadow_map shadow;
8908b2f7 RK	33	};
	34
	35	static inline struct nilfs_dat_info NILFS_DAT_I(struct inode dat)
	36	{
	37	return (struct nilfs_dat_info *)NILFS_MDT(dat);
	38	}
	39
a17564f5 KS	40	static int nilfs_dat_prepare_entry(struct inode *dat,
	41	struct nilfs_palloc_req *req, int create)
	42	{
	43	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
	44	create, &req->pr_entry_bh);
	45	}
	46
	47	static void nilfs_dat_commit_entry(struct inode *dat,
	48	struct nilfs_palloc_req *req)
	49	{
5fc7b141	50	mark_buffer_dirty(req->pr_entry_bh);
a17564f5 KS	51	nilfs_mdt_mark_dirty(dat);
	52	brelse(req->pr_entry_bh);
	53	}
	54
	55	static void nilfs_dat_abort_entry(struct inode *dat,
	56	struct nilfs_palloc_req *req)
	57	{
	58	brelse(req->pr_entry_bh);
	59	}
	60
	61	int nilfs_dat_prepare_alloc(struct inode dat, struct nilfs_palloc_req req)
	62	{
	63	int ret;
	64
	65	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
	66	if (ret < 0)
	67	return ret;
	68
	69	ret = nilfs_dat_prepare_entry(dat, req, 1);
	70	if (ret < 0)
	71	nilfs_palloc_abort_alloc_entry(dat, req);
	72
	73	return ret;
	74	}
	75
	76	void nilfs_dat_commit_alloc(struct inode dat, struct nilfs_palloc_req req)
	77	{
	78	struct nilfs_dat_entry *entry;
	79	void *kaddr;
	80
7b9c0976	81	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
a17564f5 KS	82	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	83	req->pr_entry_bh, kaddr);
	84	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
	85	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
	86	entry->de_blocknr = cpu_to_le64(0);
7b9c0976	87	kunmap_atomic(kaddr);
a17564f5 KS	88
	89	nilfs_palloc_commit_alloc_entry(dat, req);
	90	nilfs_dat_commit_entry(dat, req);
	91	}
	92
	93	void nilfs_dat_abort_alloc(struct inode dat, struct nilfs_palloc_req req)
	94	{
	95	nilfs_dat_abort_entry(dat, req);
	96	nilfs_palloc_abort_alloc_entry(dat, req);
	97	}
	98
abc0b50b JS	99	static void nilfs_dat_commit_free(struct inode *dat,
abc0b50b JS	100	struct nilfs_palloc_req *req)
a17564f5 KS	101	{
	102	struct nilfs_dat_entry *entry;
	103	void *kaddr;
	104
7b9c0976	105	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
a17564f5 KS	106	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	107	req->pr_entry_bh, kaddr);
	108	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
	109	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
	110	entry->de_blocknr = cpu_to_le64(0);
7b9c0976	111	kunmap_atomic(kaddr);
a17564f5 KS	112
	113	nilfs_dat_commit_entry(dat, req);
	114	nilfs_palloc_commit_free_entry(dat, req);
	115	}
	116
a17564f5 KS	117	int nilfs_dat_prepare_start(struct inode dat, struct nilfs_palloc_req req)
	118	{
	119	int ret;
	120
	121	ret = nilfs_dat_prepare_entry(dat, req, 0);
1f5abe7e	122	WARN_ON(ret == -ENOENT);
a17564f5 KS	123	return ret;
	124	}
	125
	126	void nilfs_dat_commit_start(struct inode dat, struct nilfs_palloc_req req,
	127	sector_t blocknr)
	128	{
	129	struct nilfs_dat_entry *entry;
	130	void *kaddr;
	131
7b9c0976	132	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
a17564f5 KS	133	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	134	req->pr_entry_bh, kaddr);
	135	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
a17564f5	136	entry->de_blocknr = cpu_to_le64(blocknr);
7b9c0976	137	kunmap_atomic(kaddr);
a17564f5 KS	138
	139	nilfs_dat_commit_entry(dat, req);
	140	}
	141
a17564f5 KS	142	int nilfs_dat_prepare_end(struct inode dat, struct nilfs_palloc_req req)
	143	{
	144	struct nilfs_dat_entry *entry;
a17564f5 KS	145	sector_t blocknr;
	146	void *kaddr;
	147	int ret;
	148
	149	ret = nilfs_dat_prepare_entry(dat, req, 0);
	150	if (ret < 0) {
1f5abe7e	151	WARN_ON(ret == -ENOENT);
a17564f5 KS	152	return ret;
	153	}
	154
7b9c0976	155	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
a17564f5 KS	156	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
a17564f5 KS	157	req->pr_entry_bh, kaddr);
a17564f5	158	blocknr = le64_to_cpu(entry->de_blocknr);
7b9c0976	159	kunmap_atomic(kaddr);
a17564f5 KS	160
	161	if (blocknr == 0) {
	162	ret = nilfs_palloc_prepare_free_entry(dat, req);
	163	if (ret < 0) {
	164	nilfs_dat_abort_entry(dat, req);
	165	return ret;
	166	}
	167	}
	168
	169	return 0;
	170	}
	171
	172	void nilfs_dat_commit_end(struct inode dat, struct nilfs_palloc_req req,
	173	int dead)
	174	{
	175	struct nilfs_dat_entry *entry;
	176	__u64 start, end;
	177	sector_t blocknr;
	178	void *kaddr;
	179
7b9c0976	180	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
a17564f5 KS	181	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	182	req->pr_entry_bh, kaddr);
	183	end = start = le64_to_cpu(entry->de_start);
	184	if (!dead) {
	185	end = nilfs_mdt_cno(dat);
1f5abe7e	186	WARN_ON(start > end);
a17564f5 KS	187	}
	188	entry->de_end = cpu_to_le64(end);
	189	blocknr = le64_to_cpu(entry->de_blocknr);
7b9c0976	190	kunmap_atomic(kaddr);
a17564f5 KS	191
	192	if (blocknr == 0)
	193	nilfs_dat_commit_free(dat, req);
	194	else
	195	nilfs_dat_commit_entry(dat, req);
	196	}
	197
	198	void nilfs_dat_abort_end(struct inode dat, struct nilfs_palloc_req req)
	199	{
	200	struct nilfs_dat_entry *entry;
	201	__u64 start;
	202	sector_t blocknr;
	203	void *kaddr;
	204
7b9c0976	205	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
a17564f5 KS	206	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
	207	req->pr_entry_bh, kaddr);
	208	start = le64_to_cpu(entry->de_start);
	209	blocknr = le64_to_cpu(entry->de_blocknr);
7b9c0976	210	kunmap_atomic(kaddr);
a17564f5 KS	211
	212	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
	213	nilfs_palloc_abort_free_entry(dat, req);
	214	nilfs_dat_abort_entry(dat, req);
	215	}
	216
bd8169ef RK	217	int nilfs_dat_prepare_update(struct inode *dat,
	218	struct nilfs_palloc_req *oldreq,
	219	struct nilfs_palloc_req *newreq)
	220	{
	221	int ret;
	222
	223	ret = nilfs_dat_prepare_end(dat, oldreq);
	224	if (!ret) {
	225	ret = nilfs_dat_prepare_alloc(dat, newreq);
	226	if (ret < 0)
	227	nilfs_dat_abort_end(dat, oldreq);
	228	}
	229	return ret;
	230	}
	231
	232	void nilfs_dat_commit_update(struct inode *dat,
	233	struct nilfs_palloc_req *oldreq,
	234	struct nilfs_palloc_req *newreq, int dead)
	235	{
	236	nilfs_dat_commit_end(dat, oldreq, dead);
	237	nilfs_dat_commit_alloc(dat, newreq);
	238	}
	239
	240	void nilfs_dat_abort_update(struct inode *dat,
	241	struct nilfs_palloc_req *oldreq,
	242	struct nilfs_palloc_req *newreq)
	243	{
	244	nilfs_dat_abort_end(dat, oldreq);
	245	nilfs_dat_abort_alloc(dat, newreq);
	246	}
	247
a17564f5 KS	248	/**
	249	* nilfs_dat_mark_dirty -
	250	* @dat: DAT file inode
	251	* @vblocknr: virtual block number
	252	*
	253	* Description:
	254	*
	255	* Return Value: On success, 0 is returned. On error, one of the following
	256	* negative error codes is returned.
	257	*
	258	* %-EIO - I/O error.
	259	*
	260	* %-ENOMEM - Insufficient amount of memory available.
	261	*/
	262	int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
	263	{
	264	struct nilfs_palloc_req req;
	265	int ret;
	266
	267	req.pr_entry_nr = vblocknr;
	268	ret = nilfs_dat_prepare_entry(dat, &req, 0);
	269	if (ret == 0)
	270	nilfs_dat_commit_entry(dat, &req);
	271	return ret;
	272	}
	273
	274	/**
	275	* nilfs_dat_freev - free virtual block numbers
	276	* @dat: DAT file inode
	277	* @vblocknrs: array of virtual block numbers
	278	* @nitems: number of virtual block numbers
	279	*
	280	* Description: nilfs_dat_freev() frees the virtual block numbers specified by
	281	* @vblocknrs and @nitems.
	282	*
	283	* Return Value: On success, 0 is returned. On error, one of the following
7a65004b	284	* negative error codes is returned.
a17564f5 KS	285	*
	286	* %-EIO - I/O error.
	287	*
	288	* %-ENOMEM - Insufficient amount of memory available.
	289	*
	290	* %-ENOENT - The virtual block number have not been allocated.
	291	*/
	292	int nilfs_dat_freev(struct inode dat, __u64 vblocknrs, size_t nitems)
	293	{
	294	return nilfs_palloc_freev(dat, vblocknrs, nitems);
	295	}
	296
	297	/**
	298	* nilfs_dat_move - change a block number
	299	* @dat: DAT file inode
	300	* @vblocknr: virtual block number
	301	* @blocknr: block number
	302	*
	303	* Description: nilfs_dat_move() changes the block number associated with
	304	* @vblocknr to @blocknr.
	305	*
	306	* Return Value: On success, 0 is returned. On error, one of the following
	307	* negative error codes is returned.
	308	*
	309	* %-EIO - I/O error.
	310	*
	311	* %-ENOMEM - Insufficient amount of memory available.
	312	*/
	313	int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
	314	{
	315	struct buffer_head *entry_bh;
	316	struct nilfs_dat_entry *entry;
	317	void *kaddr;
	318	int ret;
	319
	320	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
	321	if (ret < 0)
	322	return ret;
c1c1d709 RK	323
	324	/*
	325	* The given disk block number (blocknr) is not yet written to
	326	* the device at this point.
	327	*
	328	* To prevent nilfs_dat_translate() from returning the
f6c26ec5	329	* uncommitted block number, this makes a copy of the entry
c1c1d709 RK	330	* buffer and redirects nilfs_dat_translate() to the copy.
	331	*/
	332	if (!buffer_nilfs_redirected(entry_bh)) {
	333	ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
	334	if (ret) {
	335	brelse(entry_bh);
	336	return ret;
	337	}
	338	}
	339
7b9c0976	340	kaddr = kmap_atomic(entry_bh->b_page);
a17564f5	341	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
1f5abe7e	342	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
feee880f RK	343	nilfs_msg(dat->i_sb, KERN_CRIT,
	344	"%s: invalid vblocknr = %llu, [%llu, %llu)",
	345	__func__, (unsigned long long)vblocknr,
	346	(unsigned long long)le64_to_cpu(entry->de_start),
	347	(unsigned long long)le64_to_cpu(entry->de_end));
7b9c0976	348	kunmap_atomic(kaddr);
1f5abe7e RK	349	brelse(entry_bh);
1f5abe7e RK	350	return -EINVAL;
a17564f5	351	}
1f5abe7e	352	WARN_ON(blocknr == 0);
a17564f5	353	entry->de_blocknr = cpu_to_le64(blocknr);
7b9c0976	354	kunmap_atomic(kaddr);
a17564f5	355
5fc7b141	356	mark_buffer_dirty(entry_bh);
a17564f5 KS	357	nilfs_mdt_mark_dirty(dat);
	358
	359	brelse(entry_bh);
	360
	361	return 0;
	362	}
	363
	364	/**
	365	* nilfs_dat_translate - translate a virtual block number to a block number
	366	* @dat: DAT file inode
	367	* @vblocknr: virtual block number
	368	* @blocknrp: pointer to a block number
	369	*
	370	* Description: nilfs_dat_translate() maps the virtual block number @vblocknr
	371	* to the corresponding block number.
	372	*
	373	* Return Value: On success, 0 is returned and the block number associated
	374	* with @vblocknr is stored in the place pointed by @blocknrp. On error, one
	375	* of the following negative error codes is returned.
	376	*
	377	* %-EIO - I/O error.
	378	*
	379	* %-ENOMEM - Insufficient amount of memory available.
	380	*
	381	* %-ENOENT - A block number associated with @vblocknr does not exist.
	382	*/
	383	int nilfs_dat_translate(struct inode dat, __u64 vblocknr, sector_t blocknrp)
	384	{
c1c1d709	385	struct buffer_head entry_bh, bh;
a17564f5 KS	386	struct nilfs_dat_entry *entry;
	387	sector_t blocknr;
	388	void *kaddr;
	389	int ret;
	390
	391	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
	392	if (ret < 0)
	393	return ret;
	394
c1c1d709 RK	395	if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
	396	bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
	397	if (bh) {
	398	WARN_ON(!buffer_uptodate(bh));
	399	brelse(entry_bh);
	400	entry_bh = bh;
	401	}
	402	}
	403
7b9c0976	404	kaddr = kmap_atomic(entry_bh->b_page);
a17564f5 KS	405	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
	406	blocknr = le64_to_cpu(entry->de_blocknr);
	407	if (blocknr == 0) {
	408	ret = -ENOENT;
	409	goto out;
	410	}
086d1764	411	*blocknrp = blocknr;
a17564f5 KS	412
a17564f5 KS	413	out:
7b9c0976	414	kunmap_atomic(kaddr);
a17564f5 KS	415	brelse(entry_bh);
	416	return ret;
	417	}
	418
0c6c44cb	419	ssize_t nilfs_dat_get_vinfo(struct inode dat, void buf, unsigned int visz,
a17564f5 KS	420	size_t nvi)
	421	{
	422	struct buffer_head *entry_bh;
	423	struct nilfs_dat_entry *entry;
003ff182	424	struct nilfs_vinfo *vinfo = buf;
a17564f5 KS	425	__u64 first, last;
	426	void *kaddr;
	427	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
	428	int i, j, n, ret;
	429
	430	for (i = 0; i < nvi; i += n) {
003ff182	431	ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
a17564f5 KS	432	0, &entry_bh);
	433	if (ret < 0)
	434	return ret;
7b9c0976	435	kaddr = kmap_atomic(entry_bh->b_page);
a17564f5	436	/* last virtual block number in this block */
003ff182	437	first = vinfo->vi_vblocknr;
a17564f5 KS	438	do_div(first, entries_per_block);
	439	first *= entries_per_block;
	440	last = first + entries_per_block - 1;
	441	for (j = i, n = 0;
003ff182 RK	442	j < nvi && vinfo->vi_vblocknr >= first &&
	443	vinfo->vi_vblocknr <= last;
	444	j++, n++, vinfo = (void *)vinfo + visz) {
a17564f5	445	entry = nilfs_palloc_block_get_entry(
003ff182 RK	446	dat, vinfo->vi_vblocknr, entry_bh, kaddr);
	447	vinfo->vi_start = le64_to_cpu(entry->de_start);
	448	vinfo->vi_end = le64_to_cpu(entry->de_end);
	449	vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
a17564f5	450	}
7b9c0976	451	kunmap_atomic(kaddr);
a17564f5 KS	452	brelse(entry_bh);
	453	}
	454
	455	return nvi;
	456	}
79739565	457
8707df38	458	/**
f1e89c86 RK	459	* nilfs_dat_read - read or get dat inode
f1e89c86 RK	460	* @sb: super block instance
79739565	461	* @entry_size: size of a dat entry
f1e89c86 RK	462	* @raw_inode: on-disk dat inode
f1e89c86 RK	463	* @inodep: buffer to store the inode
79739565	464	*/
f1e89c86 RK	465	int nilfs_dat_read(struct super_block *sb, size_t entry_size,
f1e89c86 RK	466	struct nilfs_inode raw_inode, struct inode *inodep)
79739565 RK	467	{
	468	static struct lock_class_key dat_lock_key;
	469	struct inode *dat;
8908b2f7	470	struct nilfs_dat_info *di;
79739565 RK	471	int err;
79739565 RK	472
0ec060d1	473	if (entry_size > sb->s_blocksize) {
feee880f RK	474	nilfs_msg(sb, KERN_ERR, "too large DAT entry size: %zu bytes",
feee880f RK	475	entry_size);
0ec060d1 RK	476	return -EINVAL;
0ec060d1 RK	477	} else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
feee880f RK	478	nilfs_msg(sb, KERN_ERR, "too small DAT entry size: %zu bytes",
feee880f RK	479	entry_size);
0ec060d1 RK	480	return -EINVAL;
	481	}
	482
f1e89c86 RK	483	dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
	484	if (unlikely(!dat))
	485	return -ENOMEM;
	486	if (!(dat->i_state & I_NEW))
	487	goto out;
8908b2f7	488
f1e89c86 RK	489	err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
	490	if (err)
	491	goto failed;
	492
	493	err = nilfs_palloc_init_blockgroup(dat, entry_size);
	494	if (err)
	495	goto failed;
	496
	497	di = NILFS_DAT_I(dat);
	498	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
	499	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
	500	nilfs_mdt_setup_shadow_map(dat, &di->shadow);
	501
	502	err = nilfs_read_inode_common(dat, raw_inode);
	503	if (err)
	504	goto failed;
	505
	506	unlock_new_inode(dat);
	507	out:
	508	*inodep = dat;
	509	return 0;
	510	failed:
	511	iget_failed(dat);
	512	return err;
79739565	513	}