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1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * NILFS block mapping.
4 *
5 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Koji Sato.
8 */
9
10#ifndef _NILFS_BMAP_H
11#define _NILFS_BMAP_H
12
13#include <linux/types.h>
14#include <linux/fs.h>
15#include <linux/buffer_head.h>
16#include <linux/nilfs2_ondisk.h> /* nilfs_binfo, nilfs_inode, etc */
17#include "alloc.h"
18#include "dat.h"
19
20#define NILFS_BMAP_INVALID_PTR 0
21
22#define nilfs_bmap_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff))
23
24
25struct nilfs_bmap;
26
27/**
28 * union nilfs_bmap_ptr_req - request for bmap ptr
29 * @bpr_ptr: bmap pointer
30 * @bpr_req: request for persistent allocator
31 */
32union nilfs_bmap_ptr_req {
33 __u64 bpr_ptr;
34 struct nilfs_palloc_req bpr_req;
35};
36
37/**
38 * struct nilfs_bmap_stats - bmap statistics
39 * @bs_nblocks: number of blocks created or deleted
40 */
41struct nilfs_bmap_stats {
42 unsigned int bs_nblocks;
43};
44
45/**
46 * struct nilfs_bmap_operations - bmap operation table
47 * @bop_lookup: single block search operation
48 * @bop_lookup_contig: consecutive block search operation
49 * @bop_insert: block insertion operation
50 * @bop_delete: block delete operation
51 * @bop_clear: block mapping resource release operation
52 * @bop_propagate: operation to propagate dirty state towards the
53 * mapping root
54 * @bop_lookup_dirty_buffers: operation to collect dirty block buffers
55 * @bop_assign: disk block address assignment operation
56 * @bop_mark: operation to mark in-use blocks as dirty for
57 * relocation by GC
58 * @bop_seek_key: find valid block key operation
59 * @bop_last_key: find last valid block key operation
60 */
61struct nilfs_bmap_operations {
62 int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *);
63 int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *,
64 unsigned int);
65 int (*bop_insert)(struct nilfs_bmap *, __u64, __u64);
66 int (*bop_delete)(struct nilfs_bmap *bmap, __u64 key, bool deform);
67 void (*bop_clear)(struct nilfs_bmap *);
68
69 int (*bop_propagate)(struct nilfs_bmap *, struct buffer_head *);
70 void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *,
71 struct list_head *);
72
73 int (*bop_assign)(struct nilfs_bmap *,
74 struct buffer_head **,
75 sector_t,
76 union nilfs_binfo *);
77 int (*bop_mark)(struct nilfs_bmap *, __u64, int);
78
79 int (*bop_seek_key)(const struct nilfs_bmap *, __u64, __u64 *);
80 int (*bop_last_key)(const struct nilfs_bmap *, __u64 *);
81
82 /* private: internal use only */
83 int (*bop_check_insert)(const struct nilfs_bmap *, __u64);
84 int (*bop_check_delete)(struct nilfs_bmap *, __u64);
85 int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int);
86};
87
88
89#define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64))
90#define NILFS_BMAP_KEY_BIT BITS_PER_LONG
91#define NILFS_BMAP_NEW_PTR_INIT (1UL << (BITS_PER_LONG - 1))
92
93static inline int nilfs_bmap_is_new_ptr(unsigned long ptr)
94{
95 return !!(ptr & NILFS_BMAP_NEW_PTR_INIT);
96}
97
98
99/**
100 * struct nilfs_bmap - bmap structure
101 * @b_u: raw data
102 * @b_sem: semaphore
103 * @b_inode: owner of bmap
104 * @b_ops: bmap operation table
105 * @b_last_allocated_key: last allocated key for data block
106 * @b_last_allocated_ptr: last allocated ptr for data block
107 * @b_ptr_type: pointer type
108 * @b_state: state
109 * @b_nchildren_per_block: maximum number of child nodes for non-root nodes
110 */
111struct nilfs_bmap {
112 union {
113 __u8 u_flags;
114 __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)];
115 } b_u;
116 struct rw_semaphore b_sem;
117 struct inode *b_inode;
118 const struct nilfs_bmap_operations *b_ops;
119 __u64 b_last_allocated_key;
120 __u64 b_last_allocated_ptr;
121 int b_ptr_type;
122 int b_state;
123 __u16 b_nchildren_per_block;
124};
125
126/* pointer type */
127#define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */
128#define NILFS_BMAP_PTR_VS 1 /*
129 * virtual block number (single
130 * version)
131 */
132#define NILFS_BMAP_PTR_VM 2 /*
133 * virtual block number (has multiple
134 * versions)
135 */
136#define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */
137
138#define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0)
139
140/* state */
141#define NILFS_BMAP_DIRTY 0x00000001
142
143/**
144 * struct nilfs_bmap_store - shadow copy of bmap state
145 * @data: cached raw block mapping of on-disk inode
146 * @last_allocated_key: cached value of last allocated key for data block
147 * @last_allocated_ptr: cached value of last allocated ptr for data block
148 * @state: cached value of state field of bmap structure
149 */
150struct nilfs_bmap_store {
151 __le64 data[NILFS_BMAP_SIZE / sizeof(__le64)];
152 __u64 last_allocated_key;
153 __u64 last_allocated_ptr;
154 int state;
155};
156
157int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *);
158int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *);
159void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *);
160int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned int);
161int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec);
162int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key);
163int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp);
164int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp);
165int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key);
166void nilfs_bmap_clear(struct nilfs_bmap *);
167int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *);
168void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *);
169int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **,
170 unsigned long, union nilfs_binfo *);
171int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *);
172int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int);
173
174void nilfs_bmap_init_gc(struct nilfs_bmap *);
175
176void nilfs_bmap_save(const struct nilfs_bmap *, struct nilfs_bmap_store *);
177void nilfs_bmap_restore(struct nilfs_bmap *, const struct nilfs_bmap_store *);
178
179static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key,
180 __u64 *ptr)
181{
182 return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr);
183}
184
185/*
186 * Internal use only
187 */
188struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *);
189
190static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap,
191 union nilfs_bmap_ptr_req *req,
192 struct inode *dat)
193{
194 if (dat)
195 return nilfs_dat_prepare_alloc(dat, &req->bpr_req);
196 /* ignore target ptr */
197 req->bpr_ptr = bmap->b_last_allocated_ptr++;
198 return 0;
199}
200
201static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap,
202 union nilfs_bmap_ptr_req *req,
203 struct inode *dat)
204{
205 if (dat)
206 nilfs_dat_commit_alloc(dat, &req->bpr_req);
207}
208
209static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap,
210 union nilfs_bmap_ptr_req *req,
211 struct inode *dat)
212{
213 if (dat)
214 nilfs_dat_abort_alloc(dat, &req->bpr_req);
215 else
216 bmap->b_last_allocated_ptr--;
217}
218
219static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap,
220 union nilfs_bmap_ptr_req *req,
221 struct inode *dat)
222{
223 return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0;
224}
225
226static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap,
227 union nilfs_bmap_ptr_req *req,
228 struct inode *dat)
229{
230 if (dat)
231 nilfs_dat_commit_end(dat, &req->bpr_req,
232 bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
233}
234
235static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap,
236 union nilfs_bmap_ptr_req *req,
237 struct inode *dat)
238{
239 if (dat)
240 nilfs_dat_abort_end(dat, &req->bpr_req);
241}
242
243static inline void nilfs_bmap_set_target_v(struct nilfs_bmap *bmap, __u64 key,
244 __u64 ptr)
245{
246 bmap->b_last_allocated_key = key;
247 bmap->b_last_allocated_ptr = ptr;
248}
249
250__u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *,
251 const struct buffer_head *);
252
253__u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64);
254__u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *);
255
256
257/* Assume that bmap semaphore is locked. */
258static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap)
259{
260 return !!(bmap->b_state & NILFS_BMAP_DIRTY);
261}
262
263/* Assume that bmap semaphore is locked. */
264static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap)
265{
266 bmap->b_state |= NILFS_BMAP_DIRTY;
267}
268
269/* Assume that bmap semaphore is locked. */
270static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap)
271{
272 bmap->b_state &= ~NILFS_BMAP_DIRTY;
273}
274
275
276#define NILFS_BMAP_LARGE 0x1
277
278#define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN
279#define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX
280#define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX
281#define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX
282
283#endif /* _NILFS_BMAP_H */