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_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff)) 36 37 38struct nilfs_bmap; 39 40/** 41 * union nilfs_bmap_ptr_req - request for bmap ptr 42 * @bpr_ptr: bmap pointer 43 * @bpr_req: request for persistent allocator 44 */ 45union nilfs_bmap_ptr_req { 46 __u64 bpr_ptr; 47 struct nilfs_palloc_req bpr_req; 48}; 49 50/** 51 * struct nilfs_bmap_stats - bmap statistics 52 * @bs_nblocks: number of blocks created or deleted 53 */ 54struct nilfs_bmap_stats { 55 unsigned int bs_nblocks; 56}; 57 58/** 59 * struct nilfs_bmap_operations - bmap operation table 60 */ 61struct 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); 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 /* The following functions are internal use only. */ 80 int (*bop_last_key)(const struct nilfs_bmap *, __u64 *); 81 int (*bop_check_insert)(const struct nilfs_bmap *, __u64); 82 int (*bop_check_delete)(struct nilfs_bmap *, __u64); 83 int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int); 84}; 85 86 87#define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64)) 88#define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */) 89#define NILFS_BMAP_NEW_PTR_INIT \ 90 (1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1)) 91 92static inline int nilfs_bmap_is_new_ptr(unsigned long ptr) 93{ 94 return !!(ptr & NILFS_BMAP_NEW_PTR_INIT); 95} 96 97 98/** 99 * struct nilfs_bmap - bmap structure 100 * @b_u: raw data 101 * @b_sem: semaphore 102 * @b_inode: owner of bmap 103 * @b_ops: bmap operation table 104 * @b_last_allocated_key: last allocated key for data block 105 * @b_last_allocated_ptr: last allocated ptr for data block 106 * @b_ptr_type: pointer type 107 * @b_state: state 108 * @b_nchildren_per_block: maximum number of child nodes for non-root nodes 109 */ 110struct nilfs_bmap { 111 union { 112 __u8 u_flags; 113 __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)]; 114 } b_u; 115 struct rw_semaphore b_sem; 116 struct inode *b_inode; 117 const struct nilfs_bmap_operations *b_ops; 118 __u64 b_last_allocated_key; 119 __u64 b_last_allocated_ptr; 120 int b_ptr_type; 121 int b_state; 122 __u16 b_nchildren_per_block; 123}; 124 125/* pointer type */ 126#define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */ 127#define NILFS_BMAP_PTR_VS 1 /* virtual block number (single 128 version) */ 129#define NILFS_BMAP_PTR_VM 2 /* virtual block number (has multiple 130 versions) */ 131#define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */ 132 133#define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0) 134 135/* state */ 136#define NILFS_BMAP_DIRTY 0x00000001 137 138 139int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *); 140int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *); 141void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *); 142int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned); 143int nilfs_bmap_insert(struct nilfs_bmap *, unsigned long, unsigned long); 144int nilfs_bmap_delete(struct nilfs_bmap *, unsigned long); 145int nilfs_bmap_last_key(struct nilfs_bmap *, unsigned long *); 146int nilfs_bmap_truncate(struct nilfs_bmap *, unsigned long); 147void nilfs_bmap_clear(struct nilfs_bmap *); 148int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *); 149void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *); 150int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **, 151 unsigned long, union nilfs_binfo *); 152int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *); 153int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int); 154 155void nilfs_bmap_init_gc(struct nilfs_bmap *); 156void nilfs_bmap_init_gcdat(struct nilfs_bmap *, struct nilfs_bmap *); 157void nilfs_bmap_commit_gcdat(struct nilfs_bmap *, struct nilfs_bmap *); 158 159 160static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key, 161 __u64 *ptr) 162{ 163 return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr); 164} 165 166/* 167 * Internal use only 168 */ 169struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *); 170 171static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap, 172 union nilfs_bmap_ptr_req *req, 173 struct inode *dat) 174{ 175 if (dat) 176 return nilfs_dat_prepare_alloc(dat, &req->bpr_req); 177 /* ignore target ptr */ 178 req->bpr_ptr = bmap->b_last_allocated_ptr++; 179 return 0; 180} 181 182static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap, 183 union nilfs_bmap_ptr_req *req, 184 struct inode *dat) 185{ 186 if (dat) 187 nilfs_dat_commit_alloc(dat, &req->bpr_req); 188} 189 190static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap, 191 union nilfs_bmap_ptr_req *req, 192 struct inode *dat) 193{ 194 if (dat) 195 nilfs_dat_abort_alloc(dat, &req->bpr_req); 196 else 197 bmap->b_last_allocated_ptr--; 198} 199 200static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap, 201 union nilfs_bmap_ptr_req *req, 202 struct inode *dat) 203{ 204 return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0; 205} 206 207static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap, 208 union nilfs_bmap_ptr_req *req, 209 struct inode *dat) 210{ 211 if (dat) 212 nilfs_dat_commit_end(dat, &req->bpr_req, 213 bmap->b_ptr_type == NILFS_BMAP_PTR_VS); 214} 215 216static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap, 217 union nilfs_bmap_ptr_req *req, 218 struct inode *dat) 219{ 220 if (dat) 221 nilfs_dat_abort_end(dat, &req->bpr_req); 222} 223 224static inline void nilfs_bmap_set_target_v(struct nilfs_bmap *bmap, __u64 key, 225 __u64 ptr) 226{ 227 bmap->b_last_allocated_key = key; 228 bmap->b_last_allocated_ptr = ptr; 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 237void nilfs_bmap_add_blocks(const struct nilfs_bmap *, int); 238void nilfs_bmap_sub_blocks(const struct nilfs_bmap *, int); 239 240 241/* Assume that bmap semaphore is locked. */ 242static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap) 243{ 244 return !!(bmap->b_state & NILFS_BMAP_DIRTY); 245} 246 247/* Assume that bmap semaphore is locked. */ 248static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap) 249{ 250 bmap->b_state |= NILFS_BMAP_DIRTY; 251} 252 253/* Assume that bmap semaphore is locked. */ 254static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap) 255{ 256 bmap->b_state &= ~NILFS_BMAP_DIRTY; 257} 258 259 260#define NILFS_BMAP_LARGE 0x1 261 262#define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN 263#define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX 264#define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX 265#define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX 266 267#endif /* _NILFS_BMAP_H */ 268