2 * alloc.h - persistent object (dat entry/disk inode) allocator/deallocator
4 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
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.
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.
16 * Original code was written by Koji Sato <koji@osrg.net>.
17 * Two allocators were unified by Ryusuke Konishi <ryusuke@osrg.net>,
18 * Amagai Yoshiji <amagai@osrg.net>.
21 #ifndef _NILFS_ALLOC_H
22 #define _NILFS_ALLOC_H
24 #include <linux/types.h>
25 #include <linux/buffer_head.h>
29 * nilfs_palloc_entries_per_group - get the number of entries per group
30 * @inode: inode of metadata file using this allocator
32 * The number of entries per group is defined by the number of bits
33 * that a bitmap block can maintain.
35 static inline unsigned long
36 nilfs_palloc_entries_per_group(const struct inode *inode)
38 return 1UL << (inode->i_blkbits + 3 /* log2(8 = CHAR_BITS) */);
41 int nilfs_palloc_init_blockgroup(struct inode *, unsigned);
42 int nilfs_palloc_get_entry_block(struct inode *, __u64, int,
43 struct buffer_head **);
44 void *nilfs_palloc_block_get_entry(const struct inode *, __u64,
45 const struct buffer_head *, void *);
47 int nilfs_palloc_count_max_entries(struct inode *, u64, u64 *);
50 * nilfs_palloc_req - persistent allocator request and reply
51 * @pr_entry_nr: entry number (vblocknr or inode number)
52 * @pr_desc_bh: buffer head of the buffer containing block group descriptors
53 * @pr_bitmap_bh: buffer head of the buffer containing a block group bitmap
54 * @pr_entry_bh: buffer head of the buffer containing translation entries
56 struct nilfs_palloc_req {
58 struct buffer_head *pr_desc_bh;
59 struct buffer_head *pr_bitmap_bh;
60 struct buffer_head *pr_entry_bh;
63 int nilfs_palloc_prepare_alloc_entry(struct inode *,
64 struct nilfs_palloc_req *);
65 void nilfs_palloc_commit_alloc_entry(struct inode *,
66 struct nilfs_palloc_req *);
67 void nilfs_palloc_abort_alloc_entry(struct inode *, struct nilfs_palloc_req *);
68 void nilfs_palloc_commit_free_entry(struct inode *, struct nilfs_palloc_req *);
69 int nilfs_palloc_prepare_free_entry(struct inode *, struct nilfs_palloc_req *);
70 void nilfs_palloc_abort_free_entry(struct inode *, struct nilfs_palloc_req *);
71 int nilfs_palloc_freev(struct inode *, __u64 *, size_t);
73 #define nilfs_set_bit_atomic ext2_set_bit_atomic
74 #define nilfs_clear_bit_atomic ext2_clear_bit_atomic
75 #define nilfs_find_next_zero_bit find_next_zero_bit_le
76 #define nilfs_find_next_bit find_next_bit_le
79 * struct nilfs_bh_assoc - block offset and buffer head association
80 * @blkoff: block offset
83 struct nilfs_bh_assoc {
85 struct buffer_head *bh;
89 * struct nilfs_palloc_cache - persistent object allocator cache
90 * @lock: cache protecting lock
91 * @prev_desc: blockgroup descriptors cache
92 * @prev_bitmap: blockgroup bitmap cache
93 * @prev_entry: translation entries cache
95 struct nilfs_palloc_cache {
97 struct nilfs_bh_assoc prev_desc;
98 struct nilfs_bh_assoc prev_bitmap;
99 struct nilfs_bh_assoc prev_entry;
102 void nilfs_palloc_setup_cache(struct inode *inode,
103 struct nilfs_palloc_cache *cache);
104 void nilfs_palloc_clear_cache(struct inode *inode);
105 void nilfs_palloc_destroy_cache(struct inode *inode);
107 #endif /* _NILFS_ALLOC_H */