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 struct nilfs_root; 33 34 /** 35 * struct nilfs_recovery_info - Recovery information 36 * @ri_need_recovery: Recovery status 37 * @ri_super_root: Block number of the last super root 38 * @ri_ri_cno: Number of the last checkpoint 39 * @ri_lsegs_start: Region for roll-forwarding (start block number) 40 * @ri_lsegs_end: Region for roll-forwarding (end block number) 41 * @ri_lseg_start_seq: Sequence value of the segment at ri_lsegs_start 42 * @ri_used_segments: List of segments to be mark active 43 * @ri_pseg_start: Block number of the last partial segment 44 * @ri_seq: Sequence number on the last partial segment 45 * @ri_segnum: Segment number on the last partial segment 46 * @ri_nextnum: Next segment number on the last partial segment 47 */ 48 struct nilfs_recovery_info { 49 int ri_need_recovery; 50 sector_t ri_super_root; 51 __u64 ri_cno; 52 53 sector_t ri_lsegs_start; 54 sector_t ri_lsegs_end; 55 u64 ri_lsegs_start_seq; 56 struct list_head ri_used_segments; 57 sector_t ri_pseg_start; 58 u64 ri_seq; 59 __u64 ri_segnum; 60 __u64 ri_nextnum; 61 }; 62 63 /* ri_need_recovery */ 64 #define NILFS_RECOVERY_SR_UPDATED 1 /* The super root was updated */ 65 #define NILFS_RECOVERY_ROLLFORWARD_DONE 2 /* Rollforward was carried out */ 66 67 /** 68 * struct nilfs_cstage - Context of collection stage 69 * @scnt: Stage count 70 * @flags: State flags 71 * @dirty_file_ptr: Pointer on dirty_files list, or inode of a target file 72 * @gc_inode_ptr: Pointer on the list of gc-inodes 73 */ 74 struct nilfs_cstage { 75 int scnt; 76 unsigned flags; 77 struct nilfs_inode_info *dirty_file_ptr; 78 struct nilfs_inode_info *gc_inode_ptr; 79 }; 80 81 struct nilfs_segment_buffer; 82 83 struct nilfs_segsum_pointer { 84 struct buffer_head *bh; 85 unsigned offset; /* offset in bytes */ 86 }; 87 88 /** 89 * struct nilfs_sc_info - Segment constructor information 90 * @sc_super: Back pointer to super_block struct 91 * @sc_sbi: Back pointer to nilfs_sb_info struct 92 * @sc_root: root object of the current filesystem tree 93 * @sc_nblk_inc: Block count of current generation 94 * @sc_dirty_files: List of files to be written 95 * @sc_gc_inodes: List of GC inodes having blocks to be written 96 * @sc_copied_buffers: List of copied buffers (buffer heads) to freeze data 97 * @sc_freesegs: array of segment numbers to be freed 98 * @sc_nfreesegs: number of segments on @sc_freesegs 99 * @sc_dsync_inode: inode whose data pages are written for a sync operation 100 * @sc_dsync_start: start byte offset of data pages 101 * @sc_dsync_end: end byte offset of data pages (inclusive) 102 * @sc_segbufs: List of segment buffers 103 * @sc_write_logs: List of segment buffers to hold logs under writing 104 * @sc_segbuf_nblocks: Number of available blocks in segment buffers. 105 * @sc_curseg: Current segment buffer 106 * @sc_stage: Collection stage 107 * @sc_finfo_ptr: pointer to the current finfo struct in the segment summary 108 * @sc_binfo_ptr: pointer to the current binfo struct in the segment summary 109 * @sc_blk_cnt: Block count of a file 110 * @sc_datablk_cnt: Data block count of a file 111 * @sc_nblk_this_inc: Number of blocks included in the current logical segment 112 * @sc_seg_ctime: Creation time 113 * @sc_cno: checkpoint number of current log 114 * @sc_flags: Internal flags 115 * @sc_state_lock: spinlock for sc_state and so on 116 * @sc_state: Segctord state flags 117 * @sc_flush_request: inode bitmap of metadata files to be flushed 118 * @sc_wait_request: Client request queue 119 * @sc_wait_daemon: Daemon wait queue 120 * @sc_wait_task: Start/end wait queue to control segctord task 121 * @sc_seq_request: Request counter 122 * @sc_seq_accept: Accepted request count 123 * @sc_seq_done: Completion counter 124 * @sc_sync: Request of explicit sync operation 125 * @sc_interval: Timeout value of background construction 126 * @sc_mjcp_freq: Frequency of creating checkpoints 127 * @sc_lseg_stime: Start time of the latest logical segment 128 * @sc_watermark: Watermark for the number of dirty buffers 129 * @sc_timer: Timer for segctord 130 * @sc_task: current thread of segctord 131 */ 132 struct nilfs_sc_info { 133 struct super_block *sc_super; 134 struct nilfs_sb_info *sc_sbi; 135 struct nilfs_root *sc_root; 136 137 unsigned long sc_nblk_inc; 138 139 struct list_head sc_dirty_files; 140 struct list_head sc_gc_inodes; 141 struct list_head sc_copied_buffers; 142 143 __u64 *sc_freesegs; 144 size_t sc_nfreesegs; 145 146 struct nilfs_inode_info *sc_dsync_inode; 147 loff_t sc_dsync_start; 148 loff_t sc_dsync_end; 149 150 /* Segment buffers */ 151 struct list_head sc_segbufs; 152 struct list_head sc_write_logs; 153 unsigned long sc_segbuf_nblocks; 154 struct nilfs_segment_buffer *sc_curseg; 155 156 struct nilfs_cstage sc_stage; 157 158 struct nilfs_segsum_pointer sc_finfo_ptr; 159 struct nilfs_segsum_pointer sc_binfo_ptr; 160 unsigned long sc_blk_cnt; 161 unsigned long sc_datablk_cnt; 162 unsigned long sc_nblk_this_inc; 163 time_t sc_seg_ctime; 164 __u64 sc_cno; 165 unsigned long sc_flags; 166 167 spinlock_t sc_state_lock; 168 unsigned long sc_state; 169 unsigned long sc_flush_request; 170 171 wait_queue_head_t sc_wait_request; 172 wait_queue_head_t sc_wait_daemon; 173 wait_queue_head_t sc_wait_task; 174 175 __u32 sc_seq_request; 176 __u32 sc_seq_accepted; 177 __u32 sc_seq_done; 178 179 int sc_sync; 180 unsigned long sc_interval; 181 unsigned long sc_mjcp_freq; 182 unsigned long sc_lseg_stime; /* in 1/HZ seconds */ 183 unsigned long sc_watermark; 184 185 struct timer_list sc_timer; 186 struct task_struct *sc_task; 187 }; 188 189 /* sc_flags */ 190 enum { 191 NILFS_SC_DIRTY, /* One or more dirty meta-data blocks exist */ 192 NILFS_SC_UNCLOSED, /* Logical segment is not closed */ 193 NILFS_SC_SUPER_ROOT, /* The latest segment has a super root */ 194 NILFS_SC_PRIOR_FLUSH, /* Requesting immediate flush without making a 195 checkpoint */ 196 NILFS_SC_HAVE_DELTA, /* Next checkpoint will have update of files 197 other than DAT, cpfile, sufile, or files 198 moved by GC */ 199 }; 200 201 /* sc_state */ 202 #define NILFS_SEGCTOR_QUIT 0x0001 /* segctord is being destroyed */ 203 #define NILFS_SEGCTOR_COMMIT 0x0004 /* committed transaction exists */ 204 205 /* 206 * Constant parameters 207 */ 208 #define NILFS_SC_CLEANUP_RETRY 3 /* Retry count of construction when 209 destroying segctord */ 210 211 /* 212 * Default values of timeout, in seconds. 213 */ 214 #define NILFS_SC_DEFAULT_TIMEOUT 5 /* Timeout value of dirty blocks. 215 It triggers construction of a 216 logical segment with a super root */ 217 #define NILFS_SC_DEFAULT_SR_FREQ 30 /* Maximum frequency of super root 218 creation */ 219 220 /* 221 * The default threshold amount of data, in block counts. 222 */ 223 #define NILFS_SC_DEFAULT_WATERMARK 3600 224 225 /* super.c */ 226 extern struct kmem_cache *nilfs_transaction_cachep; 227 228 /* segment.c */ 229 extern void nilfs_relax_pressure_in_lock(struct super_block *); 230 231 extern int nilfs_construct_segment(struct super_block *); 232 extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *, 233 loff_t, loff_t); 234 extern void nilfs_flush_segment(struct super_block *, ino_t); 235 extern int nilfs_clean_segments(struct super_block *, struct nilfs_argv *, 236 void **); 237 238 int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi, 239 struct nilfs_root *root); 240 extern void nilfs_detach_segment_constructor(struct nilfs_sb_info *); 241 242 /* recovery.c */ 243 extern int nilfs_read_super_root_block(struct the_nilfs *, sector_t, 244 struct buffer_head **, int); 245 extern int nilfs_search_super_root(struct the_nilfs *, 246 struct nilfs_recovery_info *); 247 extern int nilfs_salvage_orphan_logs(struct the_nilfs *, 248 struct nilfs_sb_info *, 249 struct nilfs_recovery_info *); 250 extern void nilfs_dispose_segment_list(struct list_head *); 251 252 #endif /* _NILFS_SEGMENT_H */ 253