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Diffstat (limited to 'fs/nilfs2/direct.h')
| -rw-r--r-- | fs/nilfs2/direct.h | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/fs/nilfs2/direct.h b/fs/nilfs2/direct.h new file mode 100644 index 000000000000..45d2c5cda812 --- /dev/null +++ b/fs/nilfs2/direct.h @@ -0,0 +1,78 @@ +/* + * direct.h - NILFS direct block pointer. + * + * 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 + * + * Written by Koji Sato <koji@osrg.net>. + */ + +#ifndef _NILFS_DIRECT_H +#define _NILFS_DIRECT_H + +#include <linux/types.h> +#include <linux/buffer_head.h> +#include "bmap.h" + + +struct nilfs_direct; + +/** + * struct nilfs_direct_operations - direct mapping operation table + */ +struct nilfs_direct_operations { + __u64 (*dop_find_target)(const struct nilfs_direct *, __u64); + void (*dop_set_target)(struct nilfs_direct *, __u64, __u64); + int (*dop_propagate)(struct nilfs_direct *, struct buffer_head *); + int (*dop_assign)(struct nilfs_direct *, __u64, __u64, + struct buffer_head **, sector_t, + union nilfs_binfo *); +}; + +/** + * struct nilfs_direct_node - direct node + * @dn_flags: flags + * @dn_pad: padding + */ +struct nilfs_direct_node { + __u8 dn_flags; + __u8 pad[7]; +}; + +/** + * struct nilfs_direct - direct mapping + * @d_bmap: bmap structure + * @d_ops: direct mapping operation table + */ +struct nilfs_direct { + struct nilfs_bmap d_bmap; + + /* direct-mapping-specific members */ + const struct nilfs_direct_operations *d_ops; +}; + + +#define NILFS_DIRECT_NBLOCKS (NILFS_BMAP_SIZE / sizeof(__le64) - 1) +#define NILFS_DIRECT_KEY_MIN 0 +#define NILFS_DIRECT_KEY_MAX (NILFS_DIRECT_NBLOCKS - 1) + + +int nilfs_direct_init(struct nilfs_bmap *, __u64, __u64); +int nilfs_direct_delete_and_convert(struct nilfs_bmap *, __u64, __u64 *, + __u64 *, int, __u64, __u64); + + +#endif /* _NILFS_DIRECT_H */ |