1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_JOURNAL_TYPES_H
#define _BCACHEFS_JOURNAL_TYPES_H
#include <linux/cache.h>
#include <linux/workqueue.h>
#include "alloc_types.h"
#include "super_types.h"
#include "fifo.h"
#define JOURNAL_BUF_BITS 2
#define JOURNAL_BUF_NR (1U << JOURNAL_BUF_BITS)
#define JOURNAL_BUF_MASK (JOURNAL_BUF_NR - 1)
/*
* We put JOURNAL_BUF_NR of these in struct journal; we used them for writes to
* the journal that are being staged or in flight.
*/
struct journal_buf {
struct jset *data;
__BKEY_PADDED(key, BCH_REPLICAS_MAX);
struct bch_devs_list devs_written;
struct closure_waitlist wait;
u64 last_seq; /* copy of data->last_seq */
unsigned buf_size; /* size in bytes of @data */
unsigned sectors; /* maximum size for current entry */
unsigned disk_sectors; /* maximum size entry could have been, if
buf_size was bigger */
unsigned u64s_reserved;
bool noflush; /* write has already been kicked off, and was noflush */
bool must_flush; /* something wants a flush */
bool separate_flush;
};
/*
* Something that makes a journal entry dirty - i.e. a btree node that has to be
* flushed:
*/
struct journal_entry_pin_list {
struct list_head list;
struct list_head key_cache_list;
struct list_head flushed;
atomic_t count;
struct bch_devs_list devs;
};
struct journal;
struct journal_entry_pin;
typedef int (*journal_pin_flush_fn)(struct journal *j,
struct journal_entry_pin *, u64);
struct journal_entry_pin {
struct list_head list;
journal_pin_flush_fn flush;
u64 seq;
};
struct journal_res {
bool ref;
u8 idx;
u16 u64s;
u32 offset;
u64 seq;
};
/*
* For reserving space in the journal prior to getting a reservation on a
* particular journal entry:
*/
struct journal_preres {
unsigned u64s;
};
union journal_res_state {
struct {
atomic64_t counter;
};
struct {
u64 v;
};
struct {
u64 cur_entry_offset:20,
idx:2,
unwritten_idx:2,
buf0_count:10,
buf1_count:10,
buf2_count:10,
buf3_count:10;
};
};
union journal_preres_state {
struct {
atomic64_t counter;
};
struct {
u64 v;
};
struct {
u64 waiting:1,
reserved:31,
remaining:32;
};
};
/* bytes: */
#define JOURNAL_ENTRY_SIZE_MIN (64U << 10) /* 64k */
#define JOURNAL_ENTRY_SIZE_MAX (4U << 20) /* 4M */
/*
* We stash some journal state as sentinal values in cur_entry_offset:
* note - cur_entry_offset is in units of u64s
*/
#define JOURNAL_ENTRY_OFFSET_MAX ((1U << 20) - 1)
#define JOURNAL_ENTRY_CLOSED_VAL (JOURNAL_ENTRY_OFFSET_MAX - 1)
#define JOURNAL_ENTRY_ERROR_VAL (JOURNAL_ENTRY_OFFSET_MAX)
struct journal_space {
/* Units of 512 bytes sectors: */
unsigned next_entry; /* How big the next journal entry can be */
unsigned total;
};
enum journal_space_from {
journal_space_discarded,
journal_space_clean_ondisk,
journal_space_clean,
journal_space_total,
journal_space_nr,
};
/*
* JOURNAL_NEED_WRITE - current (pending) journal entry should be written ASAP,
* either because something's waiting on the write to complete or because it's
* been dirty too long and the timer's expired.
*/
enum {
JOURNAL_REPLAY_DONE,
JOURNAL_STARTED,
JOURNAL_NEED_WRITE,
JOURNAL_MAY_GET_UNRESERVED,
JOURNAL_MAY_SKIP_FLUSH,
JOURNAL_NOCHANGES,
};
/* Embedded in struct bch_fs */
struct journal {
/* Fastpath stuff up front: */
unsigned long flags;
union journal_res_state reservations;
/* Max size of current journal entry */
unsigned cur_entry_u64s;
unsigned cur_entry_sectors;
/*
* 0, or -ENOSPC if waiting on journal reclaim, or -EROFS if
* insufficient devices:
*/
enum {
cur_entry_ok,
cur_entry_blocked,
cur_entry_journal_full,
cur_entry_journal_pin_full,
cur_entry_journal_stuck,
cur_entry_insufficient_devices,
} cur_entry_error;
union journal_preres_state prereserved;
/* Reserved space in journal entry to be used just prior to write */
unsigned entry_u64s_reserved;
unsigned buf_size_want;
/*
* Two journal entries -- one is currently open for new entries, the
* other is possibly being written out.
*/
struct journal_buf buf[JOURNAL_BUF_NR];
spinlock_t lock;
/* if nonzero, we may not open a new journal entry: */
unsigned blocked;
/* Used when waiting because the journal was full */
wait_queue_head_t wait;
struct closure_waitlist async_wait;
struct closure_waitlist preres_wait;
struct closure io;
struct delayed_work write_work;
/* Sequence number of most recent journal entry (last entry in @pin) */
atomic64_t seq;
/* seq, last_seq from the most recent journal entry successfully written */
u64 seq_ondisk;
u64 flushed_seq_ondisk;
u64 last_seq_ondisk;
u64 err_seq;
u64 last_empty_seq;
/*
* FIFO of journal entries whose btree updates have not yet been
* written out.
*
* Each entry is a reference count. The position in the FIFO is the
* entry's sequence number relative to @seq.
*
* The journal entry itself holds a reference count, put when the
* journal entry is written out. Each btree node modified by the journal
* entry also holds a reference count, put when the btree node is
* written.
*
* When a reference count reaches zero, the journal entry is no longer
* needed. When all journal entries in the oldest journal bucket are no
* longer needed, the bucket can be discarded and reused.
*/
struct {
u64 front, back, size, mask;
struct journal_entry_pin_list *data;
} pin;
struct journal_space space[journal_space_nr];
u64 replay_journal_seq;
u64 replay_journal_seq_end;
struct write_point wp;
spinlock_t err_lock;
struct mutex reclaim_lock;
wait_queue_head_t reclaim_wait;
struct task_struct *reclaim_thread;
bool reclaim_kicked;
unsigned long next_reclaim;
u64 nr_direct_reclaim;
u64 nr_background_reclaim;
unsigned long last_flushed;
struct journal_entry_pin *flush_in_progress;
bool flush_in_progress_dropped;
wait_queue_head_t pin_flush_wait;
/* protects advancing ja->discard_idx: */
struct mutex discard_lock;
bool can_discard;
unsigned long last_flush_write;
u64 res_get_blocked_start;
u64 need_write_time;
u64 write_start_time;
u64 nr_flush_writes;
u64 nr_noflush_writes;
struct bch2_time_stats *flush_write_time;
struct bch2_time_stats *noflush_write_time;
struct bch2_time_stats *blocked_time;
struct bch2_time_stats *flush_seq_time;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map res_map;
#endif
};
/*
* Embedded in struct bch_dev. First three fields refer to the array of journal
* buckets, in bch_sb.
*/
struct journal_device {
/*
* For each journal bucket, contains the max sequence number of the
* journal writes it contains - so we know when a bucket can be reused.
*/
u64 *bucket_seq;
unsigned sectors_free;
/*
* discard_idx <= dirty_idx_ondisk <= dirty_idx <= cur_idx:
*/
unsigned discard_idx; /* Next bucket to discard */
unsigned dirty_idx_ondisk;
unsigned dirty_idx;
unsigned cur_idx; /* Journal bucket we're currently writing to */
unsigned nr;
u64 *buckets;
/* Bio for journal reads/writes to this device */
struct bio *bio;
/* for bch_journal_read_device */
struct closure read;
};
/*
* journal_entry_res - reserve space in every journal entry:
*/
struct journal_entry_res {
unsigned u64s;
};
#endif /* _BCACHEFS_JOURNAL_TYPES_H */
|