[linux.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.
 *
 * Originally written by Koji Sato.
 * Two allocators were unified by Ryusuke Konishi and Amagai Yoshiji.
 */

#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);
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 *);

int nilfs_palloc_count_max_entries(struct inode *, u64, u64 *);

/**
 * 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	find_next_zero_bit_le
#define nilfs_find_next_bit		find_next_bit_le

/**
 * struct nilfs_bh_assoc - block offset and buffer head association
 * @blkoff: block offset
 * @bh: buffer head
 */
struct nilfs_bh_assoc {
	unsigned long blkoff;
	struct buffer_head *bh;
};

/**
 * struct nilfs_palloc_cache - persistent object allocator cache
 * @lock: cache protecting lock
 * @prev_desc: blockgroup descriptors cache
 * @prev_bitmap: blockgroup bitmap cache
 * @prev_entry: translation entries cache
 */
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	*
4b420ab4 RK	16	* Originally written by Koji Sato.
4b420ab4 RK	17	* Two allocators were unified by Ryusuke Konishi and Amagai Yoshiji.
5442680f RK	18	*/
	19
	20	#ifndef _NILFS_ALLOC_H
	21	#define _NILFS_ALLOC_H
	22
	23	#include <linux/types.h>
	24	#include <linux/buffer_head.h>
	25	#include <linux/fs.h>
	26
db55d922 RK	27	/**
	28	* nilfs_palloc_entries_per_group - get the number of entries per group
	29	* @inode: inode of metadata file using this allocator
	30	*
	31	* The number of entries per group is defined by the number of bits
	32	* that a bitmap block can maintain.
	33	*/
5442680f RK	34	static inline unsigned long
	35	nilfs_palloc_entries_per_group(const struct inode *inode)
	36	{
	37	return 1UL << (inode->i_blkbits + 3 /* log2(8 = CHAR_BITS) */);
	38	}
	39
0c6c44cb	40	int nilfs_palloc_init_blockgroup(struct inode *, unsigned int);
5442680f RK	41	int nilfs_palloc_get_entry_block(struct inode *, __u64, int,
	42	struct buffer_head **);
	43	void nilfs_palloc_block_get_entry(const struct inode , __u64,
	44	const struct buffer_head , void );
	45
c7ef972c VD	46	int nilfs_palloc_count_max_entries(struct inode , u64, u64 );
c7ef972c VD	47
5442680f	48	/**
7a65004b	49	* nilfs_palloc_req - persistent allocator request and reply
5442680f RK	50	* @pr_entry_nr: entry number (vblocknr or inode number)
	51	* @pr_desc_bh: buffer head of the buffer containing block group descriptors
	52	* @pr_bitmap_bh: buffer head of the buffer containing a block group bitmap
	53	* @pr_entry_bh: buffer head of the buffer containing translation entries
	54	*/
	55	struct nilfs_palloc_req {
	56	__u64 pr_entry_nr;
	57	struct buffer_head *pr_desc_bh;
	58	struct buffer_head *pr_bitmap_bh;
	59	struct buffer_head *pr_entry_bh;
	60	};
	61
	62	int nilfs_palloc_prepare_alloc_entry(struct inode *,
	63	struct nilfs_palloc_req *);
	64	void nilfs_palloc_commit_alloc_entry(struct inode *,
	65	struct nilfs_palloc_req *);
	66	void nilfs_palloc_abort_alloc_entry(struct inode , struct nilfs_palloc_req );
	67	void nilfs_palloc_commit_free_entry(struct inode , struct nilfs_palloc_req );
	68	int nilfs_palloc_prepare_free_entry(struct inode , struct nilfs_palloc_req );
	69	void nilfs_palloc_abort_free_entry(struct inode , struct nilfs_palloc_req );
	70	int nilfs_palloc_freev(struct inode , __u64 , size_t);
	71
	72	#define nilfs_set_bit_atomic ext2_set_bit_atomic
	73	#define nilfs_clear_bit_atomic ext2_clear_bit_atomic
a49ebbab	74	#define nilfs_find_next_zero_bit find_next_zero_bit_le
d0c14a9e	75	#define nilfs_find_next_bit find_next_bit_le
5442680f	76
f5974c8f VD	77	/**
	78	* struct nilfs_bh_assoc - block offset and buffer head association
	79	* @blkoff: block offset
	80	* @bh: buffer head
db38d5ad	81	*/
db38d5ad RK	82	struct nilfs_bh_assoc {
	83	unsigned long blkoff;
	84	struct buffer_head *bh;
	85	};
	86
f5974c8f VD	87	/**
	88	* struct nilfs_palloc_cache - persistent object allocator cache
	89	* @lock: cache protecting lock
	90	* @prev_desc: blockgroup descriptors cache
	91	* @prev_bitmap: blockgroup bitmap cache
	92	* @prev_entry: translation entries cache
	93	*/
db38d5ad RK	94	struct nilfs_palloc_cache {
	95	spinlock_t lock;
	96	struct nilfs_bh_assoc prev_desc;
	97	struct nilfs_bh_assoc prev_bitmap;
	98	struct nilfs_bh_assoc prev_entry;
	99	};
	100
	101	void nilfs_palloc_setup_cache(struct inode *inode,
	102	struct nilfs_palloc_cache *cache);
	103	void nilfs_palloc_clear_cache(struct inode *inode);
	104	void nilfs_palloc_destroy_cache(struct inode *inode);
	105
5442680f	106	#endif /* _NILFS_ALLOC_H */