1/* 2 * segment.h - NILFS Segment constructor prototypes and definitions 3 * 4 * Copyright (C) 2005-2008 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 Ryusuke Konishi <ryusuke@osrg.net> 21 * 22 */ 23#ifndef _NILFS_SEGMENT_H 24#define _NILFS_SEGMENT_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 "sb.h" 31 32/** 33 * struct nilfs_recovery_info - Recovery infomation 34 * @ri_need_recovery: Recovery status 35 * @ri_super_root: Block number of the last super root 36 * @ri_ri_cno: Number of the last checkpoint 37 * @ri_lsegs_start: Region for roll-forwarding (start block number) 38 * @ri_lsegs_end: Region for roll-forwarding (end block number) 39 * @ri_lseg_start_seq: Sequence value of the segment at ri_lsegs_start 40 * @ri_used_segments: List of segments to be mark active 41 * @ri_pseg_start: Block number of the last partial segment 42 * @ri_seq: Sequence number on the last partial segment 43 * @ri_segnum: Segment number on the last partial segment 44 * @ri_nextnum: Next segment number on the last partial segment 45 */ 46struct nilfs_recovery_info { 47 int ri_need_recovery; 48 sector_t ri_super_root; 49 __u64 ri_cno; 50 51 sector_t ri_lsegs_start; 52 sector_t ri_lsegs_end; 53 u64 ri_lsegs_start_seq; 54 struct list_head ri_used_segments; 55 sector_t ri_pseg_start; 56 u64 ri_seq; 57 __u64 ri_segnum; 58 __u64 ri_nextnum; 59}; 60 61/* ri_need_recovery */ 62#define NILFS_RECOVERY_SR_UPDATED 1 /* The super root was updated */ 63#define NILFS_RECOVERY_ROLLFORWARD_DONE 2 /* Rollforward was carried out */ 64 65/** 66 * struct nilfs_cstage - Context of collection stage 67 * @scnt: Stage count 68 * @flags: State flags 69 * @dirty_file_ptr: Pointer on dirty_files list, or inode of a target file 70 * @gc_inode_ptr: Pointer on the list of gc-inodes 71 */ 72struct nilfs_cstage { 73 int scnt; 74 unsigned flags; 75 struct nilfs_inode_info *dirty_file_ptr; 76 struct nilfs_inode_info *gc_inode_ptr; 77}; 78 79struct nilfs_segment_buffer; 80 81struct nilfs_segsum_pointer { 82 struct buffer_head *bh; 83 unsigned offset; /* offset in bytes */ 84}; 85 86/** 87 * struct nilfs_sc_info - Segment constructor information 88 * @sc_super: Back pointer to super_block struct 89 * @sc_sbi: Back pointer to nilfs_sb_info struct 90 * @sc_nblk_inc: Block count of current generation 91 * @sc_dirty_files: List of files to be written 92 * @sc_gc_inodes: List of GC inodes having blocks to be written 93 * @sc_copied_buffers: List of copied buffers (buffer heads) to freeze data 94 * @sc_freesegs: array of segment numbers to be freed 95 * @sc_nfreesegs: number of segments on @sc_freesegs 96 * @sc_dsync_inode: inode whose data pages are written for a sync operation 97 * @sc_dsync_start: start byte offset of data pages 98 * @sc_dsync_end: end byte offset of data pages (inclusive) 99 * @sc_segbufs: List of segment buffers 100 * @sc_segbuf_nblocks: Number of available blocks in segment buffers. 101 * @sc_curseg: Current segment buffer 102 * @sc_super_root: Pointer to the super root buffer 103 * @sc_stage: Collection stage 104 * @sc_finfo_ptr: pointer to the current finfo struct in the segment summary 105 * @sc_binfo_ptr: pointer to the current binfo struct in the segment summary 106 * @sc_blk_cnt: Block count of a file 107 * @sc_datablk_cnt: Data block count of a file 108 * @sc_nblk_this_inc: Number of blocks included in the current logical segment 109 * @sc_seg_ctime: Creation time 110 * @sc_flags: Internal flags 111 * @sc_state_lock: spinlock for sc_state and so on 112 * @sc_state: Segctord state flags 113 * @sc_flush_request: inode bitmap of metadata files to be flushed 114 * @sc_wait_request: Client request queue 115 * @sc_wait_daemon: Daemon wait queue 116 * @sc_wait_task: Start/end wait queue to control segctord task 117 * @sc_seq_request: Request counter 118 * @sc_seq_done: Completion counter 119 * @sc_sync: Request of explicit sync operation 120 * @sc_interval: Timeout value of background construction 121 * @sc_mjcp_freq: Frequency of creating checkpoints 122 * @sc_lseg_stime: Start time of the latest logical segment 123 * @sc_watermark: Watermark for the number of dirty buffers 124 * @sc_timer: Timer for segctord 125 * @sc_task: current thread of segctord 126 */ 127struct nilfs_sc_info { 128 struct super_block *sc_super; 129 struct nilfs_sb_info *sc_sbi; 130 131 unsigned long sc_nblk_inc; 132 133 struct list_head sc_dirty_files; 134 struct list_head sc_gc_inodes; 135 struct list_head sc_copied_buffers; 136 137 __u64 *sc_freesegs; 138 size_t sc_nfreesegs; 139 140 struct nilfs_inode_info *sc_dsync_inode; 141 loff_t sc_dsync_start; 142 loff_t sc_dsync_end; 143 144 /* Segment buffers */ 145 struct list_head sc_segbufs; 146 unsigned long sc_segbuf_nblocks; 147 struct nilfs_segment_buffer *sc_curseg; 148 struct buffer_head *sc_super_root; 149 150 struct nilfs_cstage sc_stage; 151 152 struct nilfs_segsum_pointer sc_finfo_ptr; 153 struct nilfs_segsum_pointer sc_binfo_ptr; 154 unsigned long sc_blk_cnt; 155 unsigned long sc_datablk_cnt; 156 unsigned long sc_nblk_this_inc; 157 time_t sc_seg_ctime; 158 159 unsigned long sc_flags; 160 161 spinlock_t sc_state_lock; 162 unsigned long sc_state; 163 unsigned long sc_flush_request; 164 165 wait_queue_head_t sc_wait_request; 166 wait_queue_head_t sc_wait_daemon; 167 wait_queue_head_t sc_wait_task; 168 169 __u32 sc_seq_request; 170 __u32 sc_seq_done; 171 172 int sc_sync; 173 unsigned long sc_interval; 174 unsigned long sc_mjcp_freq; 175 unsigned long sc_lseg_stime; /* in 1/HZ seconds */ 176 unsigned long sc_watermark; 177 178 struct timer_list *sc_timer; 179 struct task_struct *sc_task; 180}; 181 182/* sc_flags */ 183enum { 184 NILFS_SC_DIRTY, /* One or more dirty meta-data blocks exist */ 185 NILFS_SC_UNCLOSED, /* Logical segment is not closed */ 186 NILFS_SC_SUPER_ROOT, /* The latest segment has a super root */ 187 NILFS_SC_PRIOR_FLUSH, /* Requesting immediate flush without making a 188 checkpoint */ 189 NILFS_SC_HAVE_DELTA, /* Next checkpoint will have update of files 190 other than DAT, cpfile, sufile, or files 191 moved by GC */ 192}; 193 194/* sc_state */ 195#define NILFS_SEGCTOR_QUIT 0x0001 /* segctord is being destroyed */ 196#define NILFS_SEGCTOR_COMMIT 0x0004 /* committed transaction exists */ 197 198/* 199 * Constant parameters 200 */ 201#define NILFS_SC_CLEANUP_RETRY 3 /* Retry count of construction when 202 destroying segctord */ 203 204/* 205 * Default values of timeout, in seconds. 206 */ 207#define NILFS_SC_DEFAULT_TIMEOUT 5 /* Timeout value of dirty blocks. 208 It triggers construction of a 209 logical segment with a super root */ 210#define NILFS_SC_DEFAULT_SR_FREQ 30 /* Maximum frequency of super root 211 creation */ 212 213/* 214 * The default threshold amount of data, in block counts. 215 */ 216#define NILFS_SC_DEFAULT_WATERMARK 3600 217 218 219/* segment.c */ 220extern int nilfs_init_transaction_cache(void); 221extern void nilfs_destroy_transaction_cache(void); 222extern void nilfs_relax_pressure_in_lock(struct super_block *); 223 224extern int nilfs_construct_segment(struct super_block *); 225extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *, 226 loff_t, loff_t); 227extern void nilfs_flush_segment(struct super_block *, ino_t); 228extern int nilfs_clean_segments(struct super_block *, struct nilfs_argv *, 229 void **); 230 231extern int nilfs_attach_segment_constructor(struct nilfs_sb_info *); 232extern void nilfs_detach_segment_constructor(struct nilfs_sb_info *); 233 234/* recovery.c */ 235extern int nilfs_read_super_root_block(struct super_block *, sector_t, 236 struct buffer_head **, int); 237extern int nilfs_search_super_root(struct the_nilfs *, struct nilfs_sb_info *, 238 struct nilfs_recovery_info *); 239extern int nilfs_recover_logical_segments(struct the_nilfs *, 240 struct nilfs_sb_info *, 241 struct nilfs_recovery_info *); 242extern void nilfs_dispose_segment_list(struct list_head *); 243 244#endif /* _NILFS_SEGMENT_H */ 245