2 * bmap.h - NILFS block mapping.
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 * Written by Koji Sato.
22 #include <linux/types.h>
24 #include <linux/buffer_head.h>
25 #include <linux/nilfs2_fs.h>
29 #define NILFS_BMAP_INVALID_PTR 0
31 #define nilfs_bmap_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff))
37 * union nilfs_bmap_ptr_req - request for bmap ptr
38 * @bpr_ptr: bmap pointer
39 * @bpr_req: request for persistent allocator
41 union nilfs_bmap_ptr_req {
43 struct nilfs_palloc_req bpr_req;
47 * struct nilfs_bmap_stats - bmap statistics
48 * @bs_nblocks: number of blocks created or deleted
50 struct nilfs_bmap_stats {
51 unsigned int bs_nblocks;
55 * struct nilfs_bmap_operations - bmap operation table
57 struct nilfs_bmap_operations {
58 int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *);
59 int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *,
61 int (*bop_insert)(struct nilfs_bmap *, __u64, __u64);
62 int (*bop_delete)(struct nilfs_bmap *, __u64);
63 void (*bop_clear)(struct nilfs_bmap *);
65 int (*bop_propagate)(struct nilfs_bmap *, struct buffer_head *);
66 void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *,
69 int (*bop_assign)(struct nilfs_bmap *,
70 struct buffer_head **,
73 int (*bop_mark)(struct nilfs_bmap *, __u64, int);
75 int (*bop_seek_key)(const struct nilfs_bmap *, __u64, __u64 *);
76 int (*bop_last_key)(const struct nilfs_bmap *, __u64 *);
78 /* The following functions are internal use only. */
79 int (*bop_check_insert)(const struct nilfs_bmap *, __u64);
80 int (*bop_check_delete)(struct nilfs_bmap *, __u64);
81 int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int);
85 #define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64))
86 #define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */)
87 #define NILFS_BMAP_NEW_PTR_INIT \
88 (1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1))
90 static inline int nilfs_bmap_is_new_ptr(unsigned long ptr)
92 return !!(ptr & NILFS_BMAP_NEW_PTR_INIT);
97 * struct nilfs_bmap - bmap structure
100 * @b_inode: owner of bmap
101 * @b_ops: bmap operation table
102 * @b_last_allocated_key: last allocated key for data block
103 * @b_last_allocated_ptr: last allocated ptr for data block
104 * @b_ptr_type: pointer type
106 * @b_nchildren_per_block: maximum number of child nodes for non-root nodes
111 __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)];
113 struct rw_semaphore b_sem;
114 struct inode *b_inode;
115 const struct nilfs_bmap_operations *b_ops;
116 __u64 b_last_allocated_key;
117 __u64 b_last_allocated_ptr;
120 __u16 b_nchildren_per_block;
124 #define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */
125 #define NILFS_BMAP_PTR_VS 1 /* virtual block number (single
127 #define NILFS_BMAP_PTR_VM 2 /* virtual block number (has multiple
129 #define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */
131 #define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0)
134 #define NILFS_BMAP_DIRTY 0x00000001
137 * struct nilfs_bmap_store - shadow copy of bmap state
138 * @data: cached raw block mapping of on-disk inode
139 * @last_allocated_key: cached value of last allocated key for data block
140 * @last_allocated_ptr: cached value of last allocated ptr for data block
141 * @state: cached value of state field of bmap structure
143 struct nilfs_bmap_store {
144 __le64 data[NILFS_BMAP_SIZE / sizeof(__le64)];
145 __u64 last_allocated_key;
146 __u64 last_allocated_ptr;
150 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *);
151 int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *);
152 void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *);
153 int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned int);
154 int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec);
155 int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key);
156 int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp);
157 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp);
158 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key);
159 void nilfs_bmap_clear(struct nilfs_bmap *);
160 int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *);
161 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *);
162 int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **,
163 unsigned long, union nilfs_binfo *);
164 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *);
165 int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int);
167 void nilfs_bmap_init_gc(struct nilfs_bmap *);
169 void nilfs_bmap_save(const struct nilfs_bmap *, struct nilfs_bmap_store *);
170 void nilfs_bmap_restore(struct nilfs_bmap *, const struct nilfs_bmap_store *);
172 static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key,
175 return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr);
181 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *);
183 static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap,
184 union nilfs_bmap_ptr_req *req,
188 return nilfs_dat_prepare_alloc(dat, &req->bpr_req);
189 /* ignore target ptr */
190 req->bpr_ptr = bmap->b_last_allocated_ptr++;
194 static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap,
195 union nilfs_bmap_ptr_req *req,
199 nilfs_dat_commit_alloc(dat, &req->bpr_req);
202 static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap,
203 union nilfs_bmap_ptr_req *req,
207 nilfs_dat_abort_alloc(dat, &req->bpr_req);
209 bmap->b_last_allocated_ptr--;
212 static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap,
213 union nilfs_bmap_ptr_req *req,
216 return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0;
219 static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap,
220 union nilfs_bmap_ptr_req *req,
224 nilfs_dat_commit_end(dat, &req->bpr_req,
225 bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
228 static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap,
229 union nilfs_bmap_ptr_req *req,
233 nilfs_dat_abort_end(dat, &req->bpr_req);
236 static inline void nilfs_bmap_set_target_v(struct nilfs_bmap *bmap, __u64 key,
239 bmap->b_last_allocated_key = key;
240 bmap->b_last_allocated_ptr = ptr;
243 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *,
244 const struct buffer_head *);
246 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64);
247 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *);
250 /* Assume that bmap semaphore is locked. */
251 static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap)
253 return !!(bmap->b_state & NILFS_BMAP_DIRTY);
256 /* Assume that bmap semaphore is locked. */
257 static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap)
259 bmap->b_state |= NILFS_BMAP_DIRTY;
262 /* Assume that bmap semaphore is locked. */
263 static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap)
265 bmap->b_state &= ~NILFS_BMAP_DIRTY;
269 #define NILFS_BMAP_LARGE 0x1
271 #define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN
272 #define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX
273 #define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX
274 #define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX
276 #endif /* _NILFS_BMAP_H */