xref: /openbmc/linux/fs/nilfs2/bmap.h (revision 03ab8e6297acd1bc0eedaa050e2a1635c576fd11)
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  
25  struct 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   */
32  union 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   */
41  struct nilfs_bmap_stats {
42  	unsigned int bs_nblocks;
43  };
44  
45  /**
46   * struct nilfs_bmap_operations - bmap operation table
47   */
48  struct nilfs_bmap_operations {
49  	int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *);
50  	int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *,
51  				 unsigned int);
52  	int (*bop_insert)(struct nilfs_bmap *, __u64, __u64);
53  	int (*bop_delete)(struct nilfs_bmap *, __u64);
54  	void (*bop_clear)(struct nilfs_bmap *);
55  
56  	int (*bop_propagate)(struct nilfs_bmap *, struct buffer_head *);
57  	void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *,
58  					 struct list_head *);
59  
60  	int (*bop_assign)(struct nilfs_bmap *,
61  			  struct buffer_head **,
62  			  sector_t,
63  			  union nilfs_binfo *);
64  	int (*bop_mark)(struct nilfs_bmap *, __u64, int);
65  
66  	int (*bop_seek_key)(const struct nilfs_bmap *, __u64, __u64 *);
67  	int (*bop_last_key)(const struct nilfs_bmap *, __u64 *);
68  
69  	/* The following functions are internal use only. */
70  	int (*bop_check_insert)(const struct nilfs_bmap *, __u64);
71  	int (*bop_check_delete)(struct nilfs_bmap *, __u64);
72  	int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int);
73  };
74  
75  
76  #define NILFS_BMAP_SIZE		(NILFS_INODE_BMAP_SIZE * sizeof(__le64))
77  #define NILFS_BMAP_KEY_BIT	(sizeof(unsigned long) * 8 /* CHAR_BIT */)
78  #define NILFS_BMAP_NEW_PTR_INIT	\
79  	(1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1))
80  
nilfs_bmap_is_new_ptr(unsigned long ptr)81  static inline int nilfs_bmap_is_new_ptr(unsigned long ptr)
82  {
83  	return !!(ptr & NILFS_BMAP_NEW_PTR_INIT);
84  }
85  
86  
87  /**
88   * struct nilfs_bmap - bmap structure
89   * @b_u: raw data
90   * @b_sem: semaphore
91   * @b_inode: owner of bmap
92   * @b_ops: bmap operation table
93   * @b_last_allocated_key: last allocated key for data block
94   * @b_last_allocated_ptr: last allocated ptr for data block
95   * @b_ptr_type: pointer type
96   * @b_state: state
97   * @b_nchildren_per_block: maximum number of child nodes for non-root nodes
98   */
99  struct nilfs_bmap {
100  	union {
101  		__u8 u_flags;
102  		__le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)];
103  	} b_u;
104  	struct rw_semaphore b_sem;
105  	struct inode *b_inode;
106  	const struct nilfs_bmap_operations *b_ops;
107  	__u64 b_last_allocated_key;
108  	__u64 b_last_allocated_ptr;
109  	int b_ptr_type;
110  	int b_state;
111  	__u16 b_nchildren_per_block;
112  };
113  
114  /* pointer type */
115  #define NILFS_BMAP_PTR_P	0	/* physical block number (i.e. LBN) */
116  #define NILFS_BMAP_PTR_VS	1	/*
117  					 * virtual block number (single
118  					 * version)
119  					 */
120  #define NILFS_BMAP_PTR_VM	2	/*
121  					 * virtual block number (has multiple
122  					 * versions)
123  					 */
124  #define NILFS_BMAP_PTR_U	(-1)	/* never perform pointer operations */
125  
126  #define NILFS_BMAP_USE_VBN(bmap)	((bmap)->b_ptr_type > 0)
127  
128  /* state */
129  #define NILFS_BMAP_DIRTY	0x00000001
130  
131  /**
132   * struct nilfs_bmap_store - shadow copy of bmap state
133   * @data: cached raw block mapping of on-disk inode
134   * @last_allocated_key: cached value of last allocated key for data block
135   * @last_allocated_ptr: cached value of last allocated ptr for data block
136   * @state: cached value of state field of bmap structure
137   */
138  struct nilfs_bmap_store {
139  	__le64 data[NILFS_BMAP_SIZE / sizeof(__le64)];
140  	__u64 last_allocated_key;
141  	__u64 last_allocated_ptr;
142  	int state;
143  };
144  
145  int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *);
146  int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *);
147  void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *);
148  int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned int);
149  int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec);
150  int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key);
151  int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp);
152  int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp);
153  int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key);
154  void nilfs_bmap_clear(struct nilfs_bmap *);
155  int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *);
156  void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *);
157  int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **,
158  		      unsigned long, union nilfs_binfo *);
159  int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *);
160  int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int);
161  
162  void nilfs_bmap_init_gc(struct nilfs_bmap *);
163  
164  void nilfs_bmap_save(const struct nilfs_bmap *, struct nilfs_bmap_store *);
165  void nilfs_bmap_restore(struct nilfs_bmap *, const struct nilfs_bmap_store *);
166  
nilfs_bmap_lookup(struct nilfs_bmap * bmap,__u64 key,__u64 * ptr)167  static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key,
168  				    __u64 *ptr)
169  {
170  	return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr);
171  }
172  
173  /*
174   * Internal use only
175   */
176  struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *);
177  
nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap * bmap,union nilfs_bmap_ptr_req * req,struct inode * dat)178  static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap,
179  					       union nilfs_bmap_ptr_req *req,
180  					       struct inode *dat)
181  {
182  	if (dat)
183  		return nilfs_dat_prepare_alloc(dat, &req->bpr_req);
184  	/* ignore target ptr */
185  	req->bpr_ptr = bmap->b_last_allocated_ptr++;
186  	return 0;
187  }
188  
nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap * bmap,union nilfs_bmap_ptr_req * req,struct inode * dat)189  static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap,
190  					       union nilfs_bmap_ptr_req *req,
191  					       struct inode *dat)
192  {
193  	if (dat)
194  		nilfs_dat_commit_alloc(dat, &req->bpr_req);
195  }
196  
nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap * bmap,union nilfs_bmap_ptr_req * req,struct inode * dat)197  static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap,
198  					      union nilfs_bmap_ptr_req *req,
199  					      struct inode *dat)
200  {
201  	if (dat)
202  		nilfs_dat_abort_alloc(dat, &req->bpr_req);
203  	else
204  		bmap->b_last_allocated_ptr--;
205  }
206  
nilfs_bmap_prepare_end_ptr(struct nilfs_bmap * bmap,union nilfs_bmap_ptr_req * req,struct inode * dat)207  static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap,
208  					     union nilfs_bmap_ptr_req *req,
209  					     struct inode *dat)
210  {
211  	return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0;
212  }
213  
nilfs_bmap_commit_end_ptr(struct nilfs_bmap * bmap,union nilfs_bmap_ptr_req * req,struct inode * dat)214  static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap,
215  					     union nilfs_bmap_ptr_req *req,
216  					     struct inode *dat)
217  {
218  	if (dat)
219  		nilfs_dat_commit_end(dat, &req->bpr_req,
220  				     bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
221  }
222  
nilfs_bmap_abort_end_ptr(struct nilfs_bmap * bmap,union nilfs_bmap_ptr_req * req,struct inode * dat)223  static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap,
224  					    union nilfs_bmap_ptr_req *req,
225  					    struct inode *dat)
226  {
227  	if (dat)
228  		nilfs_dat_abort_end(dat, &req->bpr_req);
229  }
230  
nilfs_bmap_set_target_v(struct nilfs_bmap * bmap,__u64 key,__u64 ptr)231  static inline void nilfs_bmap_set_target_v(struct nilfs_bmap *bmap, __u64 key,
232  					   __u64 ptr)
233  {
234  	bmap->b_last_allocated_key = key;
235  	bmap->b_last_allocated_ptr = ptr;
236  }
237  
238  __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *,
239  			      const struct buffer_head *);
240  
241  __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64);
242  __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *);
243  
244  
245  /* Assume that bmap semaphore is locked. */
nilfs_bmap_dirty(const struct nilfs_bmap * bmap)246  static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap)
247  {
248  	return !!(bmap->b_state & NILFS_BMAP_DIRTY);
249  }
250  
251  /* Assume that bmap semaphore is locked. */
nilfs_bmap_set_dirty(struct nilfs_bmap * bmap)252  static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap)
253  {
254  	bmap->b_state |= NILFS_BMAP_DIRTY;
255  }
256  
257  /* Assume that bmap semaphore is locked. */
nilfs_bmap_clear_dirty(struct nilfs_bmap * bmap)258  static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap)
259  {
260  	bmap->b_state &= ~NILFS_BMAP_DIRTY;
261  }
262  
263  
264  #define NILFS_BMAP_LARGE	0x1
265  
266  #define NILFS_BMAP_SMALL_LOW	NILFS_DIRECT_KEY_MIN
267  #define NILFS_BMAP_SMALL_HIGH	NILFS_DIRECT_KEY_MAX
268  #define NILFS_BMAP_LARGE_LOW	NILFS_BTREE_ROOT_NCHILDREN_MAX
269  #define NILFS_BMAP_LARGE_HIGH	NILFS_BTREE_KEY_MAX
270  
271  #endif	/* _NILFS_BMAP_H */
272