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 #include "dat.h" 32 33 #define NILFS_BMAP_INVALID_PTR 0 34 35 #define nilfs_bmap_dkey_to_key(dkey) le64_to_cpu(dkey) 36 #define nilfs_bmap_key_to_dkey(key) cpu_to_le64(key) 37 #define nilfs_bmap_dptr_to_ptr(dptr) le64_to_cpu(dptr) 38 #define nilfs_bmap_ptr_to_dptr(ptr) cpu_to_le64(ptr) 39 40 #define nilfs_bmap_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff)) 41 42 43 struct nilfs_bmap; 44 45 /** 46 * union nilfs_bmap_ptr_req - request for bmap ptr 47 * @bpr_ptr: bmap pointer 48 * @bpr_req: request for persistent allocator 49 */ 50 union nilfs_bmap_ptr_req { 51 __u64 bpr_ptr; 52 struct nilfs_palloc_req bpr_req; 53 }; 54 55 /** 56 * struct nilfs_bmap_stats - bmap statistics 57 * @bs_nblocks: number of blocks created or deleted 58 */ 59 struct nilfs_bmap_stats { 60 unsigned int bs_nblocks; 61 }; 62 63 /** 64 * struct nilfs_bmap_operations - bmap operation table 65 */ 66 struct nilfs_bmap_operations { 67 int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *); 68 int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *, 69 unsigned); 70 int (*bop_insert)(struct nilfs_bmap *, __u64, __u64); 71 int (*bop_delete)(struct nilfs_bmap *, __u64); 72 void (*bop_clear)(struct nilfs_bmap *); 73 74 int (*bop_propagate)(const struct nilfs_bmap *, struct buffer_head *); 75 void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *, 76 struct list_head *); 77 78 int (*bop_assign)(struct nilfs_bmap *, 79 struct buffer_head **, 80 sector_t, 81 union nilfs_binfo *); 82 int (*bop_mark)(struct nilfs_bmap *, __u64, int); 83 84 /* The following functions are internal use only. */ 85 int (*bop_last_key)(const struct nilfs_bmap *, __u64 *); 86 int (*bop_check_insert)(const struct nilfs_bmap *, __u64); 87 int (*bop_check_delete)(struct nilfs_bmap *, __u64); 88 int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int); 89 }; 90 91 92 #define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64)) 93 #define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */) 94 #define NILFS_BMAP_NEW_PTR_INIT \ 95 (1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1)) 96 97 static inline int nilfs_bmap_is_new_ptr(unsigned long ptr) 98 { 99 return !!(ptr & NILFS_BMAP_NEW_PTR_INIT); 100 } 101 102 103 /** 104 * struct nilfs_bmap - bmap structure 105 * @b_u: raw data 106 * @b_sem: semaphore 107 * @b_inode: owner of bmap 108 * @b_ops: bmap operation table 109 * @b_last_allocated_key: last allocated key for data block 110 * @b_last_allocated_ptr: last allocated ptr for data block 111 * @b_ptr_type: pointer type 112 * @b_state: state 113 */ 114 struct nilfs_bmap { 115 union { 116 __u8 u_flags; 117 __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)]; 118 } b_u; 119 struct rw_semaphore b_sem; 120 struct inode *b_inode; 121 const struct nilfs_bmap_operations *b_ops; 122 __u64 b_last_allocated_key; 123 __u64 b_last_allocated_ptr; 124 int b_ptr_type; 125 int b_state; 126 }; 127 128 /* pointer type */ 129 #define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */ 130 #define NILFS_BMAP_PTR_VS 1 /* virtual block number (single 131 version) */ 132 #define NILFS_BMAP_PTR_VM 2 /* virtual block number (has multiple 133 versions) */ 134 #define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */ 135 136 #define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0) 137 138 /* state */ 139 #define NILFS_BMAP_DIRTY 0x00000001 140 141 142 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *); 143 int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *); 144 void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *); 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 static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key, 164 __u64 *ptr) 165 { 166 return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr); 167 } 168 169 /* 170 * Internal use only 171 */ 172 struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *); 173 174 static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap, 175 union nilfs_bmap_ptr_req *req, 176 struct inode *dat) 177 { 178 if (dat) 179 return nilfs_dat_prepare_alloc(dat, &req->bpr_req); 180 /* ignore target ptr */ 181 req->bpr_ptr = bmap->b_last_allocated_ptr++; 182 return 0; 183 } 184 185 static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap, 186 union nilfs_bmap_ptr_req *req, 187 struct inode *dat) 188 { 189 if (dat) 190 nilfs_dat_commit_alloc(dat, &req->bpr_req); 191 } 192 193 static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap, 194 union nilfs_bmap_ptr_req *req, 195 struct inode *dat) 196 { 197 if (dat) 198 nilfs_dat_abort_alloc(dat, &req->bpr_req); 199 else 200 bmap->b_last_allocated_ptr--; 201 } 202 203 static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap, 204 union nilfs_bmap_ptr_req *req, 205 struct inode *dat) 206 { 207 return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0; 208 } 209 210 static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap, 211 union nilfs_bmap_ptr_req *req, 212 struct inode *dat) 213 { 214 if (dat) 215 nilfs_dat_commit_end(dat, &req->bpr_req, 216 bmap->b_ptr_type == NILFS_BMAP_PTR_VS); 217 } 218 219 static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap, 220 union nilfs_bmap_ptr_req *req, 221 struct inode *dat) 222 { 223 if (dat) 224 nilfs_dat_abort_end(dat, &req->bpr_req); 225 } 226 227 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *, 228 const struct buffer_head *); 229 230 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64); 231 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *); 232 233 void nilfs_bmap_add_blocks(const struct nilfs_bmap *, int); 234 void nilfs_bmap_sub_blocks(const struct nilfs_bmap *, int); 235 236 237 /* Assume that bmap semaphore is locked. */ 238 static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap) 239 { 240 return !!(bmap->b_state & NILFS_BMAP_DIRTY); 241 } 242 243 /* Assume that bmap semaphore is locked. */ 244 static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap) 245 { 246 bmap->b_state |= NILFS_BMAP_DIRTY; 247 } 248 249 /* Assume that bmap semaphore is locked. */ 250 static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap) 251 { 252 bmap->b_state &= ~NILFS_BMAP_DIRTY; 253 } 254 255 256 #define NILFS_BMAP_LARGE 0x1 257 258 #define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN 259 #define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX 260 #define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX 261 #define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX 262 263 #endif /* _NILFS_BMAP_H */ 264