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Diffstat (limited to 'kernel/fs/nilfs2/bmap.h')
-rw-r--r-- | kernel/fs/nilfs2/bmap.h | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/kernel/fs/nilfs2/bmap.h b/kernel/fs/nilfs2/bmap.h new file mode 100644 index 000000000..bfa817ce4 --- /dev/null +++ b/kernel/fs/nilfs2/bmap.h @@ -0,0 +1,280 @@ +/* + * bmap.h - NILFS block mapping. + * + * 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_BMAP_H +#define _NILFS_BMAP_H + +#include <linux/types.h> +#include <linux/fs.h> +#include <linux/buffer_head.h> +#include <linux/nilfs2_fs.h> +#include "alloc.h" +#include "dat.h" + +#define NILFS_BMAP_INVALID_PTR 0 + +#define nilfs_bmap_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff)) + + +struct nilfs_bmap; + +/** + * union nilfs_bmap_ptr_req - request for bmap ptr + * @bpr_ptr: bmap pointer + * @bpr_req: request for persistent allocator + */ +union nilfs_bmap_ptr_req { + __u64 bpr_ptr; + struct nilfs_palloc_req bpr_req; +}; + +/** + * struct nilfs_bmap_stats - bmap statistics + * @bs_nblocks: number of blocks created or deleted + */ +struct nilfs_bmap_stats { + unsigned int bs_nblocks; +}; + +/** + * struct nilfs_bmap_operations - bmap operation table + */ +struct nilfs_bmap_operations { + int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *); + int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *, + unsigned); + int (*bop_insert)(struct nilfs_bmap *, __u64, __u64); + int (*bop_delete)(struct nilfs_bmap *, __u64); + void (*bop_clear)(struct nilfs_bmap *); + + int (*bop_propagate)(struct nilfs_bmap *, struct buffer_head *); + void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *, + struct list_head *); + + int (*bop_assign)(struct nilfs_bmap *, + struct buffer_head **, + sector_t, + union nilfs_binfo *); + int (*bop_mark)(struct nilfs_bmap *, __u64, int); + + int (*bop_seek_key)(const struct nilfs_bmap *, __u64, __u64 *); + int (*bop_last_key)(const struct nilfs_bmap *, __u64 *); + + /* The following functions are internal use only. */ + int (*bop_check_insert)(const struct nilfs_bmap *, __u64); + int (*bop_check_delete)(struct nilfs_bmap *, __u64); + int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int); +}; + + +#define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64)) +#define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */) +#define NILFS_BMAP_NEW_PTR_INIT \ + (1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1)) + +static inline int nilfs_bmap_is_new_ptr(unsigned long ptr) +{ + return !!(ptr & NILFS_BMAP_NEW_PTR_INIT); +} + + +/** + * struct nilfs_bmap - bmap structure + * @b_u: raw data + * @b_sem: semaphore + * @b_inode: owner of bmap + * @b_ops: bmap operation table + * @b_last_allocated_key: last allocated key for data block + * @b_last_allocated_ptr: last allocated ptr for data block + * @b_ptr_type: pointer type + * @b_state: state + * @b_nchildren_per_block: maximum number of child nodes for non-root nodes + */ +struct nilfs_bmap { + union { + __u8 u_flags; + __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)]; + } b_u; + struct rw_semaphore b_sem; + struct inode *b_inode; + const struct nilfs_bmap_operations *b_ops; + __u64 b_last_allocated_key; + __u64 b_last_allocated_ptr; + int b_ptr_type; + int b_state; + __u16 b_nchildren_per_block; +}; + +/* pointer type */ +#define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */ +#define NILFS_BMAP_PTR_VS 1 /* virtual block number (single + version) */ +#define NILFS_BMAP_PTR_VM 2 /* virtual block number (has multiple + versions) */ +#define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */ + +#define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0) + +/* state */ +#define NILFS_BMAP_DIRTY 0x00000001 + +/** + * struct nilfs_bmap_store - shadow copy of bmap state + * @data: cached raw block mapping of on-disk inode + * @last_allocated_key: cached value of last allocated key for data block + * @last_allocated_ptr: cached value of last allocated ptr for data block + * @state: cached value of state field of bmap structure + */ +struct nilfs_bmap_store { + __le64 data[NILFS_BMAP_SIZE / sizeof(__le64)]; + __u64 last_allocated_key; + __u64 last_allocated_ptr; + int state; +}; + +int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *); +int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *); +void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *); +int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned); +int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec); +int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key); +int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp); +int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp); +int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key); +void nilfs_bmap_clear(struct nilfs_bmap *); +int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *); +void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *); +int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **, + unsigned long, union nilfs_binfo *); +int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *); +int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int); + +void nilfs_bmap_init_gc(struct nilfs_bmap *); + +void nilfs_bmap_save(const struct nilfs_bmap *, struct nilfs_bmap_store *); +void nilfs_bmap_restore(struct nilfs_bmap *, const struct nilfs_bmap_store *); + +static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key, + __u64 *ptr) +{ + return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr); +} + +/* + * Internal use only + */ +struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *); + +static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap, + union nilfs_bmap_ptr_req *req, + struct inode *dat) +{ + if (dat) + return nilfs_dat_prepare_alloc(dat, &req->bpr_req); + /* ignore target ptr */ + req->bpr_ptr = bmap->b_last_allocated_ptr++; + return 0; +} + +static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap, + union nilfs_bmap_ptr_req *req, + struct inode *dat) +{ + if (dat) + nilfs_dat_commit_alloc(dat, &req->bpr_req); +} + +static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap, + union nilfs_bmap_ptr_req *req, + struct inode *dat) +{ + if (dat) + nilfs_dat_abort_alloc(dat, &req->bpr_req); + else + bmap->b_last_allocated_ptr--; +} + +static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap, + union nilfs_bmap_ptr_req *req, + struct inode *dat) +{ + return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0; +} + +static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap, + union nilfs_bmap_ptr_req *req, + struct inode *dat) +{ + if (dat) + nilfs_dat_commit_end(dat, &req->bpr_req, + bmap->b_ptr_type == NILFS_BMAP_PTR_VS); +} + +static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap, + union nilfs_bmap_ptr_req *req, + struct inode *dat) +{ + if (dat) + nilfs_dat_abort_end(dat, &req->bpr_req); +} + +static inline void nilfs_bmap_set_target_v(struct nilfs_bmap *bmap, __u64 key, + __u64 ptr) +{ + bmap->b_last_allocated_key = key; + bmap->b_last_allocated_ptr = ptr; +} + +__u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *, + const struct buffer_head *); + +__u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64); +__u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *); + + +/* Assume that bmap semaphore is locked. */ +static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap) +{ + return !!(bmap->b_state & NILFS_BMAP_DIRTY); +} + +/* Assume that bmap semaphore is locked. */ +static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap) +{ + bmap->b_state |= NILFS_BMAP_DIRTY; +} + +/* Assume that bmap semaphore is locked. */ +static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap) +{ + bmap->b_state &= ~NILFS_BMAP_DIRTY; +} + + +#define NILFS_BMAP_LARGE 0x1 + +#define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN +#define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX +#define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX +#define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX + +#endif /* _NILFS_BMAP_H */ |