1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * segment.h - NILFS Segment constructor prototypes and definitions
4 *
5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Ryusuke Konishi.
8 *
9 */
10 #ifndef _NILFS_SEGMENT_H
11 #define _NILFS_SEGMENT_H
12
13 #include <linux/types.h>
14 #include <linux/fs.h>
15 #include <linux/buffer_head.h>
16 #include <linux/workqueue.h>
17 #include "nilfs.h"
18
19 struct nilfs_root;
20
21 /**
22 * struct nilfs_recovery_info - Recovery information
23 * @ri_need_recovery: Recovery status
24 * @ri_super_root: Block number of the last super root
25 * @ri_ri_cno: Number of the last checkpoint
26 * @ri_lsegs_start: Region for roll-forwarding (start block number)
27 * @ri_lsegs_end: Region for roll-forwarding (end block number)
28 * @ri_lseg_start_seq: Sequence value of the segment at ri_lsegs_start
29 * @ri_used_segments: List of segments to be mark active
30 * @ri_pseg_start: Block number of the last partial segment
31 * @ri_seq: Sequence number on the last partial segment
32 * @ri_segnum: Segment number on the last partial segment
33 * @ri_nextnum: Next segment number on the last partial segment
34 */
35 struct nilfs_recovery_info {
36 int ri_need_recovery;
37 sector_t ri_super_root;
38 __u64 ri_cno;
39
40 sector_t ri_lsegs_start;
41 sector_t ri_lsegs_end;
42 u64 ri_lsegs_start_seq;
43 struct list_head ri_used_segments;
44 sector_t ri_pseg_start;
45 u64 ri_seq;
46 __u64 ri_segnum;
47 __u64 ri_nextnum;
48 };
49
50 /* ri_need_recovery */
51 #define NILFS_RECOVERY_SR_UPDATED 1 /* The super root was updated */
52 #define NILFS_RECOVERY_ROLLFORWARD_DONE 2 /* Rollforward was carried out */
53
54 /**
55 * struct nilfs_cstage - Context of collection stage
56 * @scnt: Stage count, must be accessed via wrappers:
57 * nilfs_sc_cstage_inc(), nilfs_sc_cstage_set(), nilfs_sc_cstage_get()
58 * @flags: State flags
59 * @dirty_file_ptr: Pointer on dirty_files list, or inode of a target file
60 * @gc_inode_ptr: Pointer on the list of gc-inodes
61 */
62 struct nilfs_cstage {
63 int scnt;
64 unsigned int flags;
65 struct nilfs_inode_info *dirty_file_ptr;
66 struct nilfs_inode_info *gc_inode_ptr;
67 };
68
69 struct nilfs_segment_buffer;
70
71 struct nilfs_segsum_pointer {
72 struct buffer_head *bh;
73 unsigned int offset; /* offset in bytes */
74 };
75
76 /**
77 * struct nilfs_sc_info - Segment constructor information
78 * @sc_super: Back pointer to super_block struct
79 * @sc_root: root object of the current filesystem tree
80 * @sc_nblk_inc: Block count of current generation
81 * @sc_dirty_files: List of files to be written
82 * @sc_gc_inodes: List of GC inodes having blocks to be written
83 * @sc_iput_queue: list of inodes for which iput should be done
84 * @sc_iput_work: work struct to defer iput call
85 * @sc_freesegs: array of segment numbers to be freed
86 * @sc_nfreesegs: number of segments on @sc_freesegs
87 * @sc_dsync_inode: inode whose data pages are written for a sync operation
88 * @sc_dsync_start: start byte offset of data pages
89 * @sc_dsync_end: end byte offset of data pages (inclusive)
90 * @sc_segbufs: List of segment buffers
91 * @sc_write_logs: List of segment buffers to hold logs under writing
92 * @sc_segbuf_nblocks: Number of available blocks in segment buffers.
93 * @sc_curseg: Current segment buffer
94 * @sc_stage: Collection stage
95 * @sc_finfo_ptr: pointer to the current finfo struct in the segment summary
96 * @sc_binfo_ptr: pointer to the current binfo struct in the segment summary
97 * @sc_blk_cnt: Block count of a file
98 * @sc_datablk_cnt: Data block count of a file
99 * @sc_nblk_this_inc: Number of blocks included in the current logical segment
100 * @sc_seg_ctime: Creation time
101 * @sc_cno: checkpoint number of current log
102 * @sc_flags: Internal flags
103 * @sc_state_lock: spinlock for sc_state and so on
104 * @sc_state: Segctord state flags
105 * @sc_flush_request: inode bitmap of metadata files to be flushed
106 * @sc_wait_request: Client request queue
107 * @sc_wait_daemon: Daemon wait queue
108 * @sc_wait_task: Start/end wait queue to control segctord task
109 * @sc_seq_request: Request counter
110 * @sc_seq_accept: Accepted request count
111 * @sc_seq_done: Completion counter
112 * @sc_sync: Request of explicit sync operation
113 * @sc_interval: Timeout value of background construction
114 * @sc_mjcp_freq: Frequency of creating checkpoints
115 * @sc_lseg_stime: Start time of the latest logical segment
116 * @sc_watermark: Watermark for the number of dirty buffers
117 * @sc_timer: Timer for segctord
118 * @sc_task: current thread of segctord
119 */
120 struct nilfs_sc_info {
121 struct super_block *sc_super;
122 struct nilfs_root *sc_root;
123
124 unsigned long sc_nblk_inc;
125
126 struct list_head sc_dirty_files;
127 struct list_head sc_gc_inodes;
128 struct list_head sc_iput_queue;
129 struct work_struct sc_iput_work;
130
131 __u64 *sc_freesegs;
132 size_t sc_nfreesegs;
133
134 struct nilfs_inode_info *sc_dsync_inode;
135 loff_t sc_dsync_start;
136 loff_t sc_dsync_end;
137
138 /* Segment buffers */
139 struct list_head sc_segbufs;
140 struct list_head sc_write_logs;
141 unsigned long sc_segbuf_nblocks;
142 struct nilfs_segment_buffer *sc_curseg;
143
144 struct nilfs_cstage sc_stage;
145
146 struct nilfs_segsum_pointer sc_finfo_ptr;
147 struct nilfs_segsum_pointer sc_binfo_ptr;
148 unsigned long sc_blk_cnt;
149 unsigned long sc_datablk_cnt;
150 unsigned long sc_nblk_this_inc;
151 time64_t sc_seg_ctime;
152 __u64 sc_cno;
153 unsigned long sc_flags;
154
155 spinlock_t sc_state_lock;
156 unsigned long sc_state;
157 unsigned long sc_flush_request;
158
159 wait_queue_head_t sc_wait_request;
160 wait_queue_head_t sc_wait_daemon;
161 wait_queue_head_t sc_wait_task;
162
163 __u32 sc_seq_request;
164 __u32 sc_seq_accepted;
165 __u32 sc_seq_done;
166
167 int sc_sync;
168 unsigned long sc_interval;
169 unsigned long sc_mjcp_freq;
170 unsigned long sc_lseg_stime; /* in 1/HZ seconds */
171 unsigned long sc_watermark;
172
173 struct timer_list sc_timer;
174 struct task_struct *sc_timer_task;
175 struct task_struct *sc_task;
176 };
177
178 /* sc_flags */
179 enum {
180 NILFS_SC_DIRTY, /* One or more dirty meta-data blocks exist */
181 NILFS_SC_UNCLOSED, /* Logical segment is not closed */
182 NILFS_SC_SUPER_ROOT, /* The latest segment has a super root */
183 NILFS_SC_PRIOR_FLUSH, /*
184 * Requesting immediate flush without making a
185 * checkpoint
186 */
187 NILFS_SC_HAVE_DELTA, /*
188 * Next checkpoint will have update of files
189 * other than DAT, cpfile, sufile, or files
190 * moved by GC.
191 */
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 /*
202 * Retry count of construction when
203 * destroying segctord
204 */
205
206 /*
207 * Default values of timeout, in seconds.
208 */
209 #define NILFS_SC_DEFAULT_TIMEOUT 5 /*
210 * Timeout value of dirty blocks.
211 * It triggers construction of a
212 * logical segment with a super root.
213 */
214 #define NILFS_SC_DEFAULT_SR_FREQ 30 /*
215 * Maximum frequency of super root
216 * creation
217 */
218
219 /*
220 * The default threshold amount of data, in block counts.
221 */
222 #define NILFS_SC_DEFAULT_WATERMARK 3600
223
224 /* super.c */
225 extern struct kmem_cache *nilfs_transaction_cachep;
226
227 /* segment.c */
228 extern void nilfs_relax_pressure_in_lock(struct super_block *);
229
230 extern int nilfs_construct_segment(struct super_block *);
231 extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *,
232 loff_t, loff_t);
233 extern void nilfs_flush_segment(struct super_block *, ino_t);
234 extern int nilfs_clean_segments(struct super_block *, struct nilfs_argv *,
235 void **);
236
237 int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root);
238 void nilfs_detach_log_writer(struct super_block *sb);
239
240 /* recovery.c */
241 extern int nilfs_read_super_root_block(struct the_nilfs *, sector_t,
242 struct buffer_head **, int);
243 extern int nilfs_search_super_root(struct the_nilfs *,
244 struct nilfs_recovery_info *);
245 int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs, struct super_block *sb,
246 struct nilfs_recovery_info *ri);
247 extern void nilfs_dispose_segment_list(struct list_head *);
248
249 #endif /* _NILFS_SEGMENT_H */