[net-next-2.6.git] / fs / nilfs2 / alloc.h

/*
 * alloc.h - persistent object (dat entry/disk inode) allocator/deallocator
 *
 * 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
 *
 * Original code was written by Koji Sato <koji@osrg.net>.
 * Two allocators were unified by Ryusuke Konishi <ryusuke@osrg.net>,
 *                                Amagai Yoshiji <amagai@osrg.net>.
 */

#ifndef _NILFS_ALLOC_H
#define _NILFS_ALLOC_H

#include <linux/types.h>
#include <linux/buffer_head.h>
#include <linux/fs.h>

/**
 * nilfs_palloc_entries_per_group - get the number of entries per group
 * @inode: inode of metadata file using this allocator
 *
 * The number of entries per group is defined by the number of bits
 * that a bitmap block can maintain.
 */
static inline unsigned long
nilfs_palloc_entries_per_group(const struct inode *inode)
{
	return 1UL << (inode->i_blkbits + 3 /* log2(8 = CHAR_BITS) */);
}

int nilfs_palloc_init_blockgroup(struct inode *, unsigned);
int nilfs_palloc_get_entry_block(struct inode *, __u64, int,
				 struct buffer_head **);
void *nilfs_palloc_block_get_entry(const struct inode *, __u64,
				   const struct buffer_head *, void *);

/**
 * nilfs_palloc_req - persistent allocator request and reply
 * @pr_entry_nr: entry number (vblocknr or inode number)
 * @pr_desc_bh: buffer head of the buffer containing block group descriptors
 * @pr_bitmap_bh: buffer head of the buffer containing a block group bitmap
 * @pr_entry_bh: buffer head of the buffer containing translation entries
 */
struct nilfs_palloc_req {
	__u64 pr_entry_nr;
	struct buffer_head *pr_desc_bh;
	struct buffer_head *pr_bitmap_bh;
	struct buffer_head *pr_entry_bh;
};

int nilfs_palloc_prepare_alloc_entry(struct inode *,
				     struct nilfs_palloc_req *);
void nilfs_palloc_commit_alloc_entry(struct inode *,
				     struct nilfs_palloc_req *);
void nilfs_palloc_abort_alloc_entry(struct inode *, struct nilfs_palloc_req *);
void nilfs_palloc_commit_free_entry(struct inode *, struct nilfs_palloc_req *);
int nilfs_palloc_prepare_free_entry(struct inode *, struct nilfs_palloc_req *);
void nilfs_palloc_abort_free_entry(struct inode *, struct nilfs_palloc_req *);
int nilfs_palloc_freev(struct inode *, __u64 *, size_t);

#define nilfs_set_bit_atomic		ext2_set_bit_atomic
#define nilfs_clear_bit_atomic		ext2_clear_bit_atomic
#define nilfs_find_next_zero_bit	ext2_find_next_zero_bit

/*
 * persistent object allocator cache
 */

struct nilfs_bh_assoc {
	unsigned long blkoff;
	struct buffer_head *bh;
};

struct nilfs_palloc_cache {
	spinlock_t lock;
	struct nilfs_bh_assoc prev_desc;
	struct nilfs_bh_assoc prev_bitmap;
	struct nilfs_bh_assoc prev_entry;
};

void nilfs_palloc_setup_cache(struct inode *inode,
			      struct nilfs_palloc_cache *cache);
void nilfs_palloc_clear_cache(struct inode *inode);
void nilfs_palloc_destroy_cache(struct inode *inode);

#endif	/* _NILFS_ALLOC_H */
Commit	Line	Data
5442680f RK	1	/*
	2	* alloc.h - persistent object (dat entry/disk inode) allocator/deallocator
	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	* Original code was written by Koji Sato <koji@osrg.net>.
	21	* Two allocators were unified by Ryusuke Konishi <ryusuke@osrg.net>,
	22	* Amagai Yoshiji <amagai@osrg.net>.
	23	*/
	24
	25	#ifndef _NILFS_ALLOC_H
	26	#define _NILFS_ALLOC_H
	27
	28	#include <linux/types.h>
	29	#include <linux/buffer_head.h>
	30	#include <linux/fs.h>
	31
db55d922 RK	32	/**
	33	* nilfs_palloc_entries_per_group - get the number of entries per group
	34	* @inode: inode of metadata file using this allocator
	35	*
	36	* The number of entries per group is defined by the number of bits
	37	* that a bitmap block can maintain.
	38	*/
5442680f RK	39	static inline unsigned long
	40	nilfs_palloc_entries_per_group(const struct inode *inode)
	41	{
	42	return 1UL << (inode->i_blkbits + 3 /* log2(8 = CHAR_BITS) */);
	43	}
	44
	45	int nilfs_palloc_init_blockgroup(struct inode *, unsigned);
	46	int nilfs_palloc_get_entry_block(struct inode *, __u64, int,
	47	struct buffer_head **);
	48	void nilfs_palloc_block_get_entry(const struct inode , __u64,
	49	const struct buffer_head , void );
	50
	51	/**
7a65004b	52	* nilfs_palloc_req - persistent allocator request and reply
5442680f RK	53	* @pr_entry_nr: entry number (vblocknr or inode number)
	54	* @pr_desc_bh: buffer head of the buffer containing block group descriptors
	55	* @pr_bitmap_bh: buffer head of the buffer containing a block group bitmap
	56	* @pr_entry_bh: buffer head of the buffer containing translation entries
	57	*/
	58	struct nilfs_palloc_req {
	59	__u64 pr_entry_nr;
	60	struct buffer_head *pr_desc_bh;
	61	struct buffer_head *pr_bitmap_bh;
	62	struct buffer_head *pr_entry_bh;
	63	};
	64
	65	int nilfs_palloc_prepare_alloc_entry(struct inode *,
	66	struct nilfs_palloc_req *);
	67	void nilfs_palloc_commit_alloc_entry(struct inode *,
	68	struct nilfs_palloc_req *);
	69	void nilfs_palloc_abort_alloc_entry(struct inode , struct nilfs_palloc_req );
	70	void nilfs_palloc_commit_free_entry(struct inode , struct nilfs_palloc_req );
	71	int nilfs_palloc_prepare_free_entry(struct inode , struct nilfs_palloc_req );
	72	void nilfs_palloc_abort_free_entry(struct inode , struct nilfs_palloc_req );
	73	int nilfs_palloc_freev(struct inode , __u64 , size_t);
	74
	75	#define nilfs_set_bit_atomic ext2_set_bit_atomic
	76	#define nilfs_clear_bit_atomic ext2_clear_bit_atomic
	77	#define nilfs_find_next_zero_bit ext2_find_next_zero_bit
	78
db38d5ad RK	79	/*
	80	* persistent object allocator cache
	81	*/
	82
	83	struct nilfs_bh_assoc {
	84	unsigned long blkoff;
	85	struct buffer_head *bh;
	86	};
	87
	88	struct nilfs_palloc_cache {
	89	spinlock_t lock;
	90	struct nilfs_bh_assoc prev_desc;
	91	struct nilfs_bh_assoc prev_bitmap;
	92	struct nilfs_bh_assoc prev_entry;
	93	};
	94
	95	void nilfs_palloc_setup_cache(struct inode *inode,
	96	struct nilfs_palloc_cache *cache);
	97	void nilfs_palloc_clear_cache(struct inode *inode);
	98	void nilfs_palloc_destroy_cache(struct inode *inode);
	99
5442680f	100	#endif /* _NILFS_ALLOC_H */