1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * 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
19struct 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 */
35struct 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 */
62struct 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
69struct nilfs_segment_buffer;
70
71struct 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 */
120struct 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 */
179enum {
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 */
225extern struct kmem_cache *nilfs_transaction_cachep;
226
227/* segment.c */
228extern void nilfs_relax_pressure_in_lock(struct super_block *);
229
230extern int nilfs_construct_segment(struct super_block *);
231extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *,
232					 loff_t, loff_t);
233extern void nilfs_flush_segment(struct super_block *, ino_t);
234extern int nilfs_clean_segments(struct super_block *, struct nilfs_argv *,
235				void **);
236
237int nilfs_attach_log_writer(struct super_block *sb, struct nilfs_root *root);
238void nilfs_detach_log_writer(struct super_block *sb);
239
240/* recovery.c */
241extern int nilfs_read_super_root_block(struct the_nilfs *, sector_t,
242				       struct buffer_head **, int);
243extern int nilfs_search_super_root(struct the_nilfs *,
244				   struct nilfs_recovery_info *);
245int nilfs_salvage_orphan_logs(struct the_nilfs *nilfs, struct super_block *sb,
246			      struct nilfs_recovery_info *ri);
247extern void nilfs_dispose_segment_list(struct list_head *);
248
249#endif /* _NILFS_SEGMENT_H */
250