1 /* 2 * bmap.h - NILFS block mapping. 3 * 4 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. 5 * 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. 10 * 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. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Koji Sato <koji@osrg.net>. 21 */ 22 23 #ifndef _NILFS_BMAP_H 24 #define _NILFS_BMAP_H 25 26 #include <linux/types.h> 27 #include <linux/fs.h> 28 #include <linux/buffer_head.h> 29 #include <linux/nilfs2_fs.h> 30 #include "alloc.h" 31 32 #define NILFS_BMAP_INVALID_PTR 0 33 34 #define nilfs_bmap_dkey_to_key(dkey) le64_to_cpu(dkey) 35 #define nilfs_bmap_key_to_dkey(key) cpu_to_le64(key) 36 #define nilfs_bmap_dptr_to_ptr(dptr) le64_to_cpu(dptr) 37 #define nilfs_bmap_ptr_to_dptr(ptr) cpu_to_le64(ptr) 38 39 #define nilfs_bmap_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff)) 40 41 42 struct nilfs_bmap; 43 44 /** 45 * union nilfs_bmap_ptr_req - request for bmap ptr 46 * @bpr_ptr: bmap pointer 47 * @bpr_req: request for persistent allocator 48 */ 49 union nilfs_bmap_ptr_req { 50 __u64 bpr_ptr; 51 struct nilfs_palloc_req bpr_req; 52 }; 53 54 /** 55 * struct nilfs_bmap_stats - bmap statistics 56 * @bs_nblocks: number of blocks created or deleted 57 */ 58 struct nilfs_bmap_stats { 59 unsigned int bs_nblocks; 60 }; 61 62 /** 63 * struct nilfs_bmap_operations - bmap operation table 64 */ 65 struct nilfs_bmap_operations { 66 int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *); 67 int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *, 68 unsigned); 69 int (*bop_insert)(struct nilfs_bmap *, __u64, __u64); 70 int (*bop_delete)(struct nilfs_bmap *, __u64); 71 void (*bop_clear)(struct nilfs_bmap *); 72 73 int (*bop_propagate)(const struct nilfs_bmap *, struct buffer_head *); 74 void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *, 75 struct list_head *); 76 77 int (*bop_assign)(struct nilfs_bmap *, 78 struct buffer_head **, 79 sector_t, 80 union nilfs_binfo *); 81 int (*bop_mark)(struct nilfs_bmap *, __u64, int); 82 83 /* The following functions are internal use only. */ 84 int (*bop_last_key)(const struct nilfs_bmap *, __u64 *); 85 int (*bop_check_insert)(const struct nilfs_bmap *, __u64); 86 int (*bop_check_delete)(struct nilfs_bmap *, __u64); 87 int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int); 88 }; 89 90 91 #define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64)) 92 #define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */) 93 #define NILFS_BMAP_NEW_PTR_INIT \ 94 (1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1)) 95 96 static inline int nilfs_bmap_is_new_ptr(unsigned long ptr) 97 { 98 return !!(ptr & NILFS_BMAP_NEW_PTR_INIT); 99 } 100 101 102 /** 103 * struct nilfs_bmap - bmap structure 104 * @b_u: raw data 105 * @b_sem: semaphore 106 * @b_inode: owner of bmap 107 * @b_ops: bmap operation table 108 * @b_last_allocated_key: last allocated key for data block 109 * @b_last_allocated_ptr: last allocated ptr for data block 110 * @b_ptr_type: pointer type 111 * @b_state: state 112 */ 113 struct nilfs_bmap { 114 union { 115 __u8 u_flags; 116 __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)]; 117 } b_u; 118 struct rw_semaphore b_sem; 119 struct inode *b_inode; 120 const struct nilfs_bmap_operations *b_ops; 121 __u64 b_last_allocated_key; 122 __u64 b_last_allocated_ptr; 123 int b_ptr_type; 124 int b_state; 125 }; 126 127 /* pointer type */ 128 #define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */ 129 #define NILFS_BMAP_PTR_VS 1 /* virtual block number (single 130 version) */ 131 #define NILFS_BMAP_PTR_VM 2 /* virtual block number (has multiple 132 versions) */ 133 #define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */ 134 135 #define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0) 136 137 /* state */ 138 #define NILFS_BMAP_DIRTY 0x00000001 139 140 141 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *); 142 int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *); 143 void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *); 144 int nilfs_bmap_lookup(struct nilfs_bmap *, unsigned long, unsigned long *); 145 int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned); 146 int nilfs_bmap_insert(struct nilfs_bmap *, unsigned long, unsigned long); 147 int nilfs_bmap_delete(struct nilfs_bmap *, unsigned long); 148 int nilfs_bmap_last_key(struct nilfs_bmap *, unsigned long *); 149 int nilfs_bmap_truncate(struct nilfs_bmap *, unsigned long); 150 void nilfs_bmap_clear(struct nilfs_bmap *); 151 int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *); 152 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *); 153 int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **, 154 unsigned long, union nilfs_binfo *); 155 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *); 156 int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int); 157 158 void nilfs_bmap_init_gc(struct nilfs_bmap *); 159 void nilfs_bmap_init_gcdat(struct nilfs_bmap *, struct nilfs_bmap *); 160 void nilfs_bmap_commit_gcdat(struct nilfs_bmap *, struct nilfs_bmap *); 161 162 163 /* 164 * Internal use only 165 */ 166 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *); 167 int nilfs_bmap_prepare_alloc_v(struct nilfs_bmap *, 168 union nilfs_bmap_ptr_req *); 169 void nilfs_bmap_commit_alloc_v(struct nilfs_bmap *, 170 union nilfs_bmap_ptr_req *); 171 void nilfs_bmap_abort_alloc_v(struct nilfs_bmap *, 172 union nilfs_bmap_ptr_req *); 173 174 static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap, 175 union nilfs_bmap_ptr_req *req) 176 { 177 if (NILFS_BMAP_USE_VBN(bmap)) 178 return nilfs_bmap_prepare_alloc_v(bmap, req); 179 /* ignore target ptr */ 180 req->bpr_ptr = bmap->b_last_allocated_ptr++; 181 return 0; 182 } 183 184 static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap, 185 union nilfs_bmap_ptr_req *req) 186 { 187 if (NILFS_BMAP_USE_VBN(bmap)) 188 nilfs_bmap_commit_alloc_v(bmap, req); 189 } 190 191 static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap, 192 union nilfs_bmap_ptr_req *req) 193 { 194 if (NILFS_BMAP_USE_VBN(bmap)) 195 nilfs_bmap_abort_alloc_v(bmap, req); 196 else 197 bmap->b_last_allocated_ptr--; 198 } 199 200 int nilfs_bmap_prepare_end_v(struct nilfs_bmap *, union nilfs_bmap_ptr_req *); 201 void nilfs_bmap_commit_end_v(struct nilfs_bmap *, union nilfs_bmap_ptr_req *); 202 void nilfs_bmap_abort_end_v(struct nilfs_bmap *, union nilfs_bmap_ptr_req *); 203 204 static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap, 205 union nilfs_bmap_ptr_req *req) 206 { 207 return NILFS_BMAP_USE_VBN(bmap) ? 208 nilfs_bmap_prepare_end_v(bmap, req) : 0; 209 } 210 211 static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap, 212 union nilfs_bmap_ptr_req *req) 213 { 214 if (NILFS_BMAP_USE_VBN(bmap)) 215 nilfs_bmap_commit_end_v(bmap, req); 216 } 217 218 static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap, 219 union nilfs_bmap_ptr_req *req) 220 { 221 if (NILFS_BMAP_USE_VBN(bmap)) 222 nilfs_bmap_abort_end_v(bmap, req); 223 } 224 225 int nilfs_bmap_start_v(struct nilfs_bmap *, union nilfs_bmap_ptr_req *, 226 sector_t); 227 int nilfs_bmap_move_v(const struct nilfs_bmap *, __u64, sector_t); 228 int nilfs_bmap_mark_dirty(const struct nilfs_bmap *, __u64); 229 230 231 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *, 232 const struct buffer_head *); 233 234 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64); 235 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *); 236 237 int nilfs_bmap_prepare_update_v(struct nilfs_bmap *, 238 union nilfs_bmap_ptr_req *, 239 union nilfs_bmap_ptr_req *); 240 void nilfs_bmap_commit_update_v(struct nilfs_bmap *, 241 union nilfs_bmap_ptr_req *, 242 union nilfs_bmap_ptr_req *); 243 void nilfs_bmap_abort_update_v(struct nilfs_bmap *, 244 union nilfs_bmap_ptr_req *, 245 union nilfs_bmap_ptr_req *); 246 247 void nilfs_bmap_add_blocks(const struct nilfs_bmap *, int); 248 void nilfs_bmap_sub_blocks(const struct nilfs_bmap *, int); 249 250 251 /* Assume that bmap semaphore is locked. */ 252 static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap) 253 { 254 return !!(bmap->b_state & NILFS_BMAP_DIRTY); 255 } 256 257 /* Assume that bmap semaphore is locked. */ 258 static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap) 259 { 260 bmap->b_state |= NILFS_BMAP_DIRTY; 261 } 262 263 /* Assume that bmap semaphore is locked. */ 264 static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap) 265 { 266 bmap->b_state &= ~NILFS_BMAP_DIRTY; 267 } 268 269 270 #define NILFS_BMAP_LARGE 0x1 271 272 #define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN 273 #define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX 274 #define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX 275 #define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX 276 277 #endif /* _NILFS_BMAP_H */ 278