mirror of
https://github.com/torvalds/linux.git
synced 2024-11-14 08:02:07 +00:00
db55d92252
The implementation of persistent object allocator (alloc.c) is poorly documented. This adds kernel doc style comments on that functions. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
101 lines
3.5 KiB
C
101 lines
3.5 KiB
C
/*
|
|
* 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 */
|