1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * bmap.h - 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 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 *); 166 167 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 *); 177 178 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 } 188 189 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 } 196 197 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 } 206 207 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 } 213 214 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 } 222 223 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 } 230 231 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. */ 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. */ 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. */ 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