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 * @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 */ 61 struct 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 *, __u64); 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 93 static 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 */ 111 struct 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 */ 150 struct 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 }; 156 157 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *); 158 int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *); 159 void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *); 160 int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned int); 161 int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec); 162 int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key); 163 int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp); 164 int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp); 165 int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key); 166 void nilfs_bmap_clear(struct nilfs_bmap *); 167 int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *); 168 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *); 169 int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **, 170 unsigned long, union nilfs_binfo *); 171 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *); 172 int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int); 173 174 void nilfs_bmap_init_gc(struct nilfs_bmap *); 175 176 void nilfs_bmap_save(const struct nilfs_bmap *, struct nilfs_bmap_store *); 177 void nilfs_bmap_restore(struct nilfs_bmap *, const struct nilfs_bmap_store *); 178 179 static 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 */ 188 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *); 189 190 static 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 } 200 201 static 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 } 208 209 static 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 } 218 219 static 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 } 225 226 static 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 } 234 235 static 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 } 242 243 static 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. */ 258 static 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. */ 264 static 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. */ 270 static 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 */ 284