2 * segment.h - NILFS Segment constructor prototypes and definitions
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
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.
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.
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
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
23 #ifndef _NILFS_SEGMENT_H
24 #define _NILFS_SEGMENT_H
26 #include <linux/types.h>
28 #include <linux/buffer_head.h>
29 #include <linux/workqueue.h>
30 #include <linux/nilfs2_fs.h>
36 * struct nilfs_recovery_info - Recovery information
37 * @ri_need_recovery: Recovery status
38 * @ri_super_root: Block number of the last super root
39 * @ri_ri_cno: Number of the last checkpoint
40 * @ri_lsegs_start: Region for roll-forwarding (start block number)
41 * @ri_lsegs_end: Region for roll-forwarding (end block number)
42 * @ri_lseg_start_seq: Sequence value of the segment at ri_lsegs_start
43 * @ri_used_segments: List of segments to be mark active
44 * @ri_pseg_start: Block number of the last partial segment
45 * @ri_seq: Sequence number on the last partial segment
46 * @ri_segnum: Segment number on the last partial segment
47 * @ri_nextnum: Next segment number on the last partial segment
49 struct nilfs_recovery_info {
51 sector_t ri_super_root;
54 sector_t ri_lsegs_start;
55 sector_t ri_lsegs_end;
56 u64 ri_lsegs_start_seq;
57 struct list_head ri_used_segments;
58 sector_t ri_pseg_start;
64 /* ri_need_recovery */
65 #define NILFS_RECOVERY_SR_UPDATED 1 /* The super root was updated */
66 #define NILFS_RECOVERY_ROLLFORWARD_DONE 2 /* Rollforward was carried out */
69 * struct nilfs_cstage - Context of collection stage
72 * @dirty_file_ptr: Pointer on dirty_files list, or inode of a target file
73 * @gc_inode_ptr: Pointer on the list of gc-inodes
78 struct nilfs_inode_info *dirty_file_ptr;
79 struct nilfs_inode_info *gc_inode_ptr;
82 struct nilfs_segment_buffer;
84 struct nilfs_segsum_pointer {
85 struct buffer_head *bh;
86 unsigned offset; /* offset in bytes */
90 * struct nilfs_sc_info - Segment constructor information
91 * @sc_super: Back pointer to super_block 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_iput_queue: list of inodes for which iput should be done
97 * @sc_iput_work: work struct to defer iput call
98 * @sc_freesegs: array of segment numbers to be freed
99 * @sc_nfreesegs: number of segments on @sc_freesegs
100 * @sc_dsync_inode: inode whose data pages are written for a sync operation
101 * @sc_dsync_start: start byte offset of data pages
102 * @sc_dsync_end: end byte offset of data pages (inclusive)
103 * @sc_segbufs: List of segment buffers
104 * @sc_write_logs: List of segment buffers to hold logs under writing
105 * @sc_segbuf_nblocks: Number of available blocks in segment buffers.
106 * @sc_curseg: Current segment buffer
107 * @sc_stage: Collection stage
108 * @sc_finfo_ptr: pointer to the current finfo struct in the segment summary
109 * @sc_binfo_ptr: pointer to the current binfo struct in the segment summary
110 * @sc_blk_cnt: Block count of a file
111 * @sc_datablk_cnt: Data block count of a file
112 * @sc_nblk_this_inc: Number of blocks included in the current logical segment
113 * @sc_seg_ctime: Creation time
114 * @sc_cno: checkpoint number of current log
115 * @sc_flags: Internal flags
116 * @sc_state_lock: spinlock for sc_state and so on
117 * @sc_state: Segctord state flags
118 * @sc_flush_request: inode bitmap of metadata files to be flushed
119 * @sc_wait_request: Client request queue
120 * @sc_wait_daemon: Daemon wait queue
121 * @sc_wait_task: Start/end wait queue to control segctord task
122 * @sc_seq_request: Request counter
123 * @sc_seq_accept: Accepted request count
124 * @sc_seq_done: Completion counter
125 * @sc_sync: Request of explicit sync operation
126 * @sc_interval: Timeout value of background construction
127 * @sc_mjcp_freq: Frequency of creating checkpoints
128 * @sc_lseg_stime: Start time of the latest logical segment
129 * @sc_watermark: Watermark for the number of dirty buffers
130 * @sc_timer: Timer for segctord
131 * @sc_task: current thread of segctord
133 struct nilfs_sc_info {
134 struct super_block *sc_super;
135 struct nilfs_root *sc_root;
137 unsigned long sc_nblk_inc;
139 struct list_head sc_dirty_files;
140 struct list_head sc_gc_inodes;
141 struct list_head sc_iput_queue;
142 struct work_struct sc_iput_work;
147 struct nilfs_inode_info *sc_dsync_inode;
148 loff_t sc_dsync_start;
151 /* Segment buffers */
152 struct list_head sc_segbufs;
153 struct list_head sc_write_logs;
154 unsigned long sc_segbuf_nblocks;
155 struct nilfs_segment_buffer *sc_curseg;
157 struct nilfs_cstage sc_stage;
159 struct nilfs_segsum_pointer sc_finfo_ptr;
160 struct nilfs_segsum_pointer sc_binfo_ptr;
161 unsigned long sc_blk_cnt;
162 unsigned long sc_datablk_cnt;
163 unsigned long sc_nblk_this_inc;
166 unsigned long sc_flags;
168 spinlock_t sc_state_lock;
169 unsigned long sc_state;
170 unsigned long sc_flush_request;
172 wait_queue_head_t sc_wait_request;
173 wait_queue_head_t sc_wait_daemon;
174 wait_queue_head_t sc_wait_task;
176 __u32 sc_seq_request;
177 __u32 sc_seq_accepted;
181 unsigned long sc_interval;
182 unsigned long sc_mjcp_freq;
183 unsigned long sc_lseg_stime; /* in 1/HZ seconds */
184 unsigned long sc_watermark;
186 struct timer_list sc_timer;
187 struct task_struct *sc_task;
192 NILFS_SC_DIRTY, /* One or more dirty meta-data blocks exist */
193 NILFS_SC_UNCLOSED, /* Logical segment is not closed */
194 NILFS_SC_SUPER_ROOT, /* The latest segment has a super root */
195 NILFS_SC_PRIOR_FLUSH, /* Requesting immediate flush without making a
197 NILFS_SC_HAVE_DELTA, /* Next checkpoint will have update of files
198 other than DAT, cpfile, sufile, or files
203 #define NILFS_SEGCTOR_QUIT 0x0001 /* segctord is being destroyed */
204 #define NILFS_SEGCTOR_COMMIT 0x0004 /* committed transaction exists */
207 * Constant parameters
209 #define NILFS_SC_CLEANUP_RETRY 3 /* Retry count of construction when
210 destroying segctord */
213 * Default values of timeout, in seconds.
215 #define NILFS_SC_DEFAULT_TIMEOUT 5 /* Timeout value of dirty blocks.
216 It triggers construction of a
217 logical segment with a super root */
218 #define NILFS_SC_DEFAULT_SR_FREQ 30 /* Maximum frequency of super root
222 * The default threshold amount of data, in block counts.
224 #define NILFS_SC_DEFAULT_WATERMARK 3600
227 extern struct kmem_cache *nilfs_transaction_cachep;
230 extern void nilfs_relax_pressure_in_lock(struct super_block *);
232 extern int nilfs_construct_segment(struct super_block *);
233 extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *,
235 extern void nilfs_flush_segment(struct super_block *, ino_t);
236 extern int nilfs_clean_segments(struct super_block *, struct nilfs_argv *,
239 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root);
240 void nilfs_detach_log_writer(struct super_block *sb);
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 int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs, struct super_block *sb,
248 struct nilfs_recovery_info *ri);
249 extern void nilfs_dispose_segment_list(struct list_head *);
251 #endif /* _NILFS_SEGMENT_H */