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 * Written by Ryusuke Konishi. 17 * 18 */ 19#ifndef _NILFS_SEGMENT_H 20#define _NILFS_SEGMENT_H 21 22#include <linux/types.h> 23#include <linux/fs.h> 24#include <linux/buffer_head.h> 25#include <linux/workqueue.h> 26#include "nilfs.h" 27 28struct nilfs_root; 29 30/** 31 * struct nilfs_recovery_info - Recovery information 32 * @ri_need_recovery: Recovery status 33 * @ri_super_root: Block number of the last super root 34 * @ri_ri_cno: Number of the last checkpoint 35 * @ri_lsegs_start: Region for roll-forwarding (start block number) 36 * @ri_lsegs_end: Region for roll-forwarding (end block number) 37 * @ri_lseg_start_seq: Sequence value of the segment at ri_lsegs_start 38 * @ri_used_segments: List of segments to be mark active 39 * @ri_pseg_start: Block number of the last partial segment 40 * @ri_seq: Sequence number on the last partial segment 41 * @ri_segnum: Segment number on the last partial segment 42 * @ri_nextnum: Next segment number on the last partial segment 43 */ 44struct nilfs_recovery_info { 45 int ri_need_recovery; 46 sector_t ri_super_root; 47 __u64 ri_cno; 48 49 sector_t ri_lsegs_start; 50 sector_t ri_lsegs_end; 51 u64 ri_lsegs_start_seq; 52 struct list_head ri_used_segments; 53 sector_t ri_pseg_start; 54 u64 ri_seq; 55 __u64 ri_segnum; 56 __u64 ri_nextnum; 57}; 58 59/* ri_need_recovery */ 60#define NILFS_RECOVERY_SR_UPDATED 1 /* The super root was updated */ 61#define NILFS_RECOVERY_ROLLFORWARD_DONE 2 /* Rollforward was carried out */ 62 63/** 64 * struct nilfs_cstage - Context of collection stage 65 * @scnt: Stage count, must be accessed via wrappers: 66 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get() 67 * @flags: State flags 68 * @dirty_file_ptr: Pointer on dirty_files list, or inode of a target file 69 * @gc_inode_ptr: Pointer on the list of gc-inodes 70 */ 71struct nilfs_cstage { 72 int scnt; 73 unsigned int flags; 74 struct nilfs_inode_info *dirty_file_ptr; 75 struct nilfs_inode_info *gc_inode_ptr; 76}; 77 78struct nilfs_segment_buffer; 79 80struct nilfs_segsum_pointer { 81 struct buffer_head *bh; 82 unsigned int offset; /* offset in bytes */ 83}; 84 85/** 86 * struct nilfs_sc_info - Segment constructor information 87 * @sc_super: Back pointer to super_block struct 88 * @sc_root: root object of the current filesystem tree 89 * @sc_nblk_inc: Block count of current generation 90 * @sc_dirty_files: List of files to be written 91 * @sc_gc_inodes: List of GC inodes having blocks to be written 92 * @sc_iput_queue: list of inodes for which iput should be done 93 * @sc_iput_work: work struct to defer iput call 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_write_logs: List of segment buffers to hold logs under writing 101 * @sc_segbuf_nblocks: Number of available blocks in segment buffers. 102 * @sc_curseg: Current segment 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_cno: checkpoint number of current log 111 * @sc_flags: Internal flags 112 * @sc_state_lock: spinlock for sc_state and so on 113 * @sc_state: Segctord state flags 114 * @sc_flush_request: inode bitmap of metadata files to be flushed 115 * @sc_wait_request: Client request queue 116 * @sc_wait_daemon: Daemon wait queue 117 * @sc_wait_task: Start/end wait queue to control segctord task 118 * @sc_seq_request: Request counter 119 * @sc_seq_accept: Accepted request count 120 * @sc_seq_done: Completion counter 121 * @sc_sync: Request of explicit sync operation 122 * @sc_interval: Timeout value of background construction 123 * @sc_mjcp_freq: Frequency of creating checkpoints 124 * @sc_lseg_stime: Start time of the latest logical segment 125 * @sc_watermark: Watermark for the number of dirty buffers 126 * @sc_timer: Timer for segctord 127 * @sc_task: current thread of segctord 128 */ 129struct nilfs_sc_info { 130 struct super_block *sc_super; 131 struct nilfs_root *sc_root; 132 133 unsigned long sc_nblk_inc; 134 135 struct list_head sc_dirty_files; 136 struct list_head sc_gc_inodes; 137 struct list_head sc_iput_queue; 138 struct work_struct sc_iput_work; 139 140 __u64 *sc_freesegs; 141 size_t sc_nfreesegs; 142 143 struct nilfs_inode_info *sc_dsync_inode; 144 loff_t sc_dsync_start; 145 loff_t sc_dsync_end; 146 147 /* Segment buffers */ 148 struct list_head sc_segbufs; 149 struct list_head sc_write_logs; 150 unsigned long sc_segbuf_nblocks; 151 struct nilfs_segment_buffer *sc_curseg; 152 153 struct nilfs_cstage sc_stage; 154 155 struct nilfs_segsum_pointer sc_finfo_ptr; 156 struct nilfs_segsum_pointer sc_binfo_ptr; 157 unsigned long sc_blk_cnt; 158 unsigned long sc_datablk_cnt; 159 unsigned long sc_nblk_this_inc; 160 time64_t sc_seg_ctime; 161 __u64 sc_cno; 162 unsigned long sc_flags; 163 164 spinlock_t sc_state_lock; 165 unsigned long sc_state; 166 unsigned long sc_flush_request; 167 168 wait_queue_head_t sc_wait_request; 169 wait_queue_head_t sc_wait_daemon; 170 wait_queue_head_t sc_wait_task; 171 172 __u32 sc_seq_request; 173 __u32 sc_seq_accepted; 174 __u32 sc_seq_done; 175 176 int sc_sync; 177 unsigned long sc_interval; 178 unsigned long sc_mjcp_freq; 179 unsigned long sc_lseg_stime; /* in 1/HZ seconds */ 180 unsigned long sc_watermark; 181 182 struct timer_list sc_timer; 183 struct task_struct *sc_timer_task; 184 struct task_struct *sc_task; 185}; 186 187/* sc_flags */ 188enum { 189 NILFS_SC_DIRTY, /* One or more dirty meta-data blocks exist */ 190 NILFS_SC_UNCLOSED, /* Logical segment is not closed */ 191 NILFS_SC_SUPER_ROOT, /* The latest segment has a super root */ 192 NILFS_SC_PRIOR_FLUSH, /* 193 * Requesting immediate flush without making a 194 * checkpoint 195 */ 196 NILFS_SC_HAVE_DELTA, /* 197 * Next checkpoint will have update of files 198 * other than DAT, cpfile, sufile, or files 199 * moved by GC. 200 */ 201}; 202 203/* sc_state */ 204#define NILFS_SEGCTOR_QUIT 0x0001 /* segctord is being destroyed */ 205#define NILFS_SEGCTOR_COMMIT 0x0004 /* committed transaction exists */ 206 207/* 208 * Constant parameters 209 */ 210#define NILFS_SC_CLEANUP_RETRY 3 /* 211 * Retry count of construction when 212 * destroying segctord 213 */ 214 215/* 216 * Default values of timeout, in seconds. 217 */ 218#define NILFS_SC_DEFAULT_TIMEOUT 5 /* 219 * Timeout value of dirty blocks. 220 * It triggers construction of a 221 * logical segment with a super root. 222 */ 223#define NILFS_SC_DEFAULT_SR_FREQ 30 /* 224 * Maximum frequency of super root 225 * creation 226 */ 227 228/* 229 * The default threshold amount of data, in block counts. 230 */ 231#define NILFS_SC_DEFAULT_WATERMARK 3600 232 233/* super.c */ 234extern struct kmem_cache *nilfs_transaction_cachep; 235 236/* segment.c */ 237extern void nilfs_relax_pressure_in_lock(struct super_block *); 238 239extern int nilfs_construct_segment(struct super_block *); 240extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *, 241 loff_t, loff_t); 242extern void nilfs_flush_segment(struct super_block *, ino_t); 243extern int nilfs_clean_segments(struct super_block *, struct nilfs_argv *, 244 void **); 245 246int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root); 247void nilfs_detach_log_writer(struct super_block *sb); 248 249/* recovery.c */ 250extern int nilfs_read_super_root_block(struct the_nilfs *, sector_t, 251 struct buffer_head **, int); 252extern int nilfs_search_super_root(struct the_nilfs *, 253 struct nilfs_recovery_info *); 254int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs, struct super_block *sb, 255 struct nilfs_recovery_info *ri); 256extern void nilfs_dispose_segment_list(struct list_head *); 257 258#endif /* _NILFS_SEGMENT_H */ 259