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Diffstat (limited to 'fs/nilfs2/btree.h')
| -rw-r--r-- | fs/nilfs2/btree.h | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/fs/nilfs2/btree.h b/fs/nilfs2/btree.h new file mode 100644 index 00000000000..4766deb52fb --- /dev/null +++ b/fs/nilfs2/btree.h @@ -0,0 +1,117 @@ +/* + * btree.h - NILFS B-tree. + * + * Copyright (C) 2005-2008 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 + * + * Written by Koji Sato <koji@osrg.net>. + */ + +#ifndef _NILFS_BTREE_H +#define _NILFS_BTREE_H + +#include <linux/types.h> +#include <linux/buffer_head.h> +#include <linux/list.h> +#include <linux/nilfs2_fs.h> +#include "btnode.h" +#include "bmap.h" + +struct nilfs_btree; +struct nilfs_btree_path; + +/** + * struct nilfs_btree_operations - B-tree operation table + */ +struct nilfs_btree_operations { + __u64 (*btop_find_target)(const struct nilfs_btree *, + const struct nilfs_btree_path *, __u64); + void (*btop_set_target)(struct nilfs_btree *, __u64, __u64); + + struct the_nilfs *(*btop_get_nilfs)(struct nilfs_btree *); + + int (*btop_propagate)(struct nilfs_btree *, + struct nilfs_btree_path *, + int, + struct buffer_head *); + int (*btop_assign)(struct nilfs_btree *, + struct nilfs_btree_path *, + int, + struct buffer_head **, + sector_t, + union nilfs_binfo *); +}; + +/** + * struct nilfs_btree_node - B-tree node + * @bn_flags: flags + * @bn_level: level + * @bn_nchildren: number of children + * @bn_pad: padding + */ +struct nilfs_btree_node { + __u8 bn_flags; + __u8 bn_level; + __le16 bn_nchildren; + __le32 bn_pad; +}; + +/* flags */ +#define NILFS_BTREE_NODE_ROOT 0x01 + +/* level */ +#define NILFS_BTREE_LEVEL_DATA 0 +#define NILFS_BTREE_LEVEL_NODE_MIN (NILFS_BTREE_LEVEL_DATA + 1) +#define NILFS_BTREE_LEVEL_MAX 14 + +/** + * struct nilfs_btree - B-tree structure + * @bt_bmap: bmap base structure + * @bt_ops: B-tree operation table + */ +struct nilfs_btree { + struct nilfs_bmap bt_bmap; + + /* B-tree-specific members */ + const struct nilfs_btree_operations *bt_ops; +}; + + +#define NILFS_BTREE_ROOT_SIZE NILFS_BMAP_SIZE +#define NILFS_BTREE_ROOT_NCHILDREN_MAX \ + ((NILFS_BTREE_ROOT_SIZE - sizeof(struct nilfs_btree_node)) / \ + (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) +#define NILFS_BTREE_ROOT_NCHILDREN_MIN 0 +#define NILFS_BTREE_NODE_EXTRA_PAD_SIZE (sizeof(__le64)) +#define NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) \ + (((nodesize) - sizeof(struct nilfs_btree_node) - \ + NILFS_BTREE_NODE_EXTRA_PAD_SIZE) / \ + (sizeof(__le64 /* dkey */) + sizeof(__le64 /* dptr */))) +#define NILFS_BTREE_NODE_NCHILDREN_MIN(nodesize) \ + ((NILFS_BTREE_NODE_NCHILDREN_MAX(nodesize) - 1) / 2 + 1) +#define NILFS_BTREE_KEY_MIN ((__u64)0) +#define NILFS_BTREE_KEY_MAX (~(__u64)0) + + +int nilfs_btree_path_cache_init(void); +void nilfs_btree_path_cache_destroy(void); +int nilfs_btree_init(struct nilfs_bmap *, __u64, __u64); +int nilfs_btree_convert_and_insert(struct nilfs_bmap *, __u64, __u64, + const __u64 *, const __u64 *, + int, __u64, __u64); +void nilfs_btree_init_gc(struct nilfs_bmap *); + +#endif /* _NILFS_BTREE_H */ |