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_insert)(struct nilfs_bmap *, __u64, __u64); 68 int (*bop_delete)(struct nilfs_bmap *, __u64); 69 void (*bop_clear)(struct nilfs_bmap *); 70 71 int (*bop_propagate)(const struct nilfs_bmap *, struct buffer_head *); 72 void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *, 73 struct list_head *); 74 75 int (*bop_assign)(struct nilfs_bmap *, 76 struct buffer_head **, 77 sector_t, 78 union nilfs_binfo *); 79 int (*bop_mark)(struct nilfs_bmap *, __u64, int); 80 81 /* The following functions are internal use only. */ 82 int (*bop_last_key)(const struct nilfs_bmap *, __u64 *); 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 /** 90 * struct nilfs_bmap_ptr_operations - bmap ptr operation table 91 */ 92 struct nilfs_bmap_ptr_operations { 93 int (*bpop_prepare_alloc_ptr)(struct nilfs_bmap *, 94 union nilfs_bmap_ptr_req *); 95 void (*bpop_commit_alloc_ptr)(struct nilfs_bmap *, 96 union nilfs_bmap_ptr_req *); 97 void (*bpop_abort_alloc_ptr)(struct nilfs_bmap *, 98 union nilfs_bmap_ptr_req *); 99 int (*bpop_prepare_start_ptr)(struct nilfs_bmap *, 100 union nilfs_bmap_ptr_req *); 101 void (*bpop_commit_start_ptr)(struct nilfs_bmap *, 102 union nilfs_bmap_ptr_req *, 103 sector_t); 104 void (*bpop_abort_start_ptr)(struct nilfs_bmap *, 105 union nilfs_bmap_ptr_req *); 106 int (*bpop_prepare_end_ptr)(struct nilfs_bmap *, 107 union nilfs_bmap_ptr_req *); 108 void (*bpop_commit_end_ptr)(struct nilfs_bmap *, 109 union nilfs_bmap_ptr_req *); 110 void (*bpop_abort_end_ptr)(struct nilfs_bmap *, 111 union nilfs_bmap_ptr_req *); 112 113 int (*bpop_translate)(const struct nilfs_bmap *, __u64, __u64 *); 114 }; 115 116 117 #define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64)) 118 #define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */) 119 #define NILFS_BMAP_NEW_PTR_INIT \ 120 (1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1)) 121 122 static inline int nilfs_bmap_is_new_ptr(unsigned long ptr) 123 { 124 return !!(ptr & NILFS_BMAP_NEW_PTR_INIT); 125 } 126 127 128 /** 129 * struct nilfs_bmap - bmap structure 130 * @b_u: raw data 131 * @b_sem: semaphore 132 * @b_inode: owner of bmap 133 * @b_ops: bmap operation table 134 * @b_pops: bmap ptr operation table 135 * @b_low: low watermark of conversion 136 * @b_high: high watermark of conversion 137 * @b_last_allocated_key: last allocated key for data block 138 * @b_last_allocated_ptr: last allocated ptr for data block 139 * @b_state: state 140 */ 141 struct nilfs_bmap { 142 union { 143 __u8 u_flags; 144 __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)]; 145 } b_u; 146 struct rw_semaphore b_sem; 147 struct inode *b_inode; 148 const struct nilfs_bmap_operations *b_ops; 149 const struct nilfs_bmap_ptr_operations *b_pops; 150 __u64 b_low; 151 __u64 b_high; 152 __u64 b_last_allocated_key; 153 __u64 b_last_allocated_ptr; 154 int b_state; 155 }; 156 157 /* state */ 158 #define NILFS_BMAP_DIRTY 0x00000001 159 160 161 int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *); 162 int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *); 163 void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *); 164 int nilfs_bmap_lookup(struct nilfs_bmap *, unsigned long, unsigned long *); 165 int nilfs_bmap_insert(struct nilfs_bmap *, unsigned long, unsigned long); 166 int nilfs_bmap_delete(struct nilfs_bmap *, unsigned long); 167 int nilfs_bmap_last_key(struct nilfs_bmap *, unsigned long *); 168 int nilfs_bmap_truncate(struct nilfs_bmap *, unsigned long); 169 void nilfs_bmap_clear(struct nilfs_bmap *); 170 int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *); 171 void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *); 172 int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **, 173 unsigned long, union nilfs_binfo *); 174 int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *); 175 int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int); 176 177 void nilfs_bmap_init_gc(struct nilfs_bmap *); 178 void nilfs_bmap_init_gcdat(struct nilfs_bmap *, struct nilfs_bmap *); 179 void nilfs_bmap_commit_gcdat(struct nilfs_bmap *, struct nilfs_bmap *); 180 181 182 /* 183 * Internal use only 184 */ 185 186 int nilfs_bmap_move_v(const struct nilfs_bmap *, __u64, sector_t); 187 int nilfs_bmap_mark_dirty(const struct nilfs_bmap *, __u64); 188 189 190 __u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *, 191 const struct buffer_head *); 192 193 __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64); 194 __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *); 195 196 int nilfs_bmap_prepare_update(struct nilfs_bmap *, 197 union nilfs_bmap_ptr_req *, 198 union nilfs_bmap_ptr_req *); 199 void nilfs_bmap_commit_update(struct nilfs_bmap *, 200 union nilfs_bmap_ptr_req *, 201 union nilfs_bmap_ptr_req *); 202 void nilfs_bmap_abort_update(struct nilfs_bmap *, 203 union nilfs_bmap_ptr_req *, 204 union nilfs_bmap_ptr_req *); 205 206 void nilfs_bmap_add_blocks(const struct nilfs_bmap *, int); 207 void nilfs_bmap_sub_blocks(const struct nilfs_bmap *, int); 208 209 210 int nilfs_bmap_get_block(const struct nilfs_bmap *, __u64, 211 struct buffer_head **); 212 void nilfs_bmap_put_block(const struct nilfs_bmap *, struct buffer_head *); 213 int nilfs_bmap_get_new_block(const struct nilfs_bmap *, __u64, 214 struct buffer_head **); 215 void nilfs_bmap_delete_block(const struct nilfs_bmap *, struct buffer_head *); 216 217 218 /* Assume that bmap semaphore is locked. */ 219 static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap) 220 { 221 return !!(bmap->b_state & NILFS_BMAP_DIRTY); 222 } 223 224 /* Assume that bmap semaphore is locked. */ 225 static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap) 226 { 227 bmap->b_state |= NILFS_BMAP_DIRTY; 228 } 229 230 /* Assume that bmap semaphore is locked. */ 231 static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap) 232 { 233 bmap->b_state &= ~NILFS_BMAP_DIRTY; 234 } 235 236 237 #define NILFS_BMAP_LARGE 0x1 238 239 #define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN 240 #define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX 241 #define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX 242 #define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX 243 244 #endif /* _NILFS_BMAP_H */ 245