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 * Originally written by Koji Sato. 17 * Two allocators were unified by Ryusuke Konishi and Amagai Yoshiji. 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 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 */ 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 40 int nilfs_palloc_init_blockgroup(struct inode *, unsigned int); 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 46 int nilfs_palloc_count_max_entries(struct inode *, u64, u64 *); 47 48 /** 49 * nilfs_palloc_req - persistent allocator request and reply 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 74 #define nilfs_find_next_zero_bit find_next_zero_bit_le 75 #define nilfs_find_next_bit find_next_bit_le 76 77 /** 78 * struct nilfs_bh_assoc - block offset and buffer head association 79 * @blkoff: block offset 80 * @bh: buffer head 81 */ 82 struct nilfs_bh_assoc { 83 unsigned long blkoff; 84 struct buffer_head *bh; 85 }; 86 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 */ 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); 105 106 #endif /* _NILFS_ALLOC_H */ 107