1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _BCACHEFS_JOURNAL_TYPES_H
3#define _BCACHEFS_JOURNAL_TYPES_H
4
5#include <linux/cache.h>
6#include <linux/workqueue.h>
7
8#include "alloc_types.h"
9#include "super_types.h"
10#include "fifo.h"
11
12#define JOURNAL_BUF_BITS 2
13#define JOURNAL_BUF_NR (1U << JOURNAL_BUF_BITS)
14#define JOURNAL_BUF_MASK (JOURNAL_BUF_NR - 1)
15
16/*
17 * We put JOURNAL_BUF_NR of these in struct journal; we used them for writes to
18 * the journal that are being staged or in flight.
19 */
20struct journal_buf {
21 struct closure io;
22 struct jset *data;
23
24 __BKEY_PADDED(key, BCH_REPLICAS_MAX);
25 struct bch_devs_list devs_written;
26
27 struct closure_waitlist wait;
28 u64 last_seq; /* copy of data->last_seq */
29 long expires;
30 u64 flush_time;
31
32 unsigned buf_size; /* size in bytes of @data */
33 unsigned sectors; /* maximum size for current entry */
34 unsigned disk_sectors; /* maximum size entry could have been, if
35 buf_size was bigger */
36 unsigned u64s_reserved;
37 bool noflush:1; /* write has already been kicked off, and was noflush */
38 bool must_flush:1; /* something wants a flush */
39 bool separate_flush:1;
40 bool need_flush_to_write_buffer:1;
41 bool write_started:1;
42 bool write_allocated:1;
43 bool write_done:1;
44 u8 idx;
45};
46
47/*
48 * Something that makes a journal entry dirty - i.e. a btree node that has to be
49 * flushed:
50 */
51
52enum journal_pin_type {
53 JOURNAL_PIN_btree,
54 JOURNAL_PIN_key_cache,
55 JOURNAL_PIN_other,
56 JOURNAL_PIN_NR,
57};
58
59struct journal_entry_pin_list {
60 struct list_head list[JOURNAL_PIN_NR];
61 struct list_head flushed;
62 atomic_t count;
63 struct bch_devs_list devs;
64};
65
66struct journal;
67struct journal_entry_pin;
68typedef int (*journal_pin_flush_fn)(struct journal *j,
69 struct journal_entry_pin *, u64);
70
71struct journal_entry_pin {
72 struct list_head list;
73 journal_pin_flush_fn flush;
74 u64 seq;
75};
76
77struct journal_res {
78 bool ref;
79 u8 idx;
80 u16 u64s;
81 u32 offset;
82 u64 seq;
83};
84
85union journal_res_state {
86 struct {
87 atomic64_t counter;
88 };
89
90 struct {
91 u64 v;
92 };
93
94 struct {
95 u64 cur_entry_offset:20,
96 idx:2,
97 unwritten_idx:2,
98 buf0_count:10,
99 buf1_count:10,
100 buf2_count:10,
101 buf3_count:10;
102 };
103};
104
105/* bytes: */
106#define JOURNAL_ENTRY_SIZE_MIN (64U << 10) /* 64k */
107#define JOURNAL_ENTRY_SIZE_MAX (4U << 20) /* 4M */
108
109/*
110 * We stash some journal state as sentinal values in cur_entry_offset:
111 * note - cur_entry_offset is in units of u64s
112 */
113#define JOURNAL_ENTRY_OFFSET_MAX ((1U << 20) - 1)
114
115#define JOURNAL_ENTRY_CLOSED_VAL (JOURNAL_ENTRY_OFFSET_MAX - 1)
116#define JOURNAL_ENTRY_ERROR_VAL (JOURNAL_ENTRY_OFFSET_MAX)
117
118struct journal_space {
119 /* Units of 512 bytes sectors: */
120 unsigned next_entry; /* How big the next journal entry can be */
121 unsigned total;
122};
123
124enum journal_space_from {
125 journal_space_discarded,
126 journal_space_clean_ondisk,
127 journal_space_clean,
128 journal_space_total,
129 journal_space_nr,
130};
131
132enum journal_flags {
133 JOURNAL_REPLAY_DONE,
134 JOURNAL_STARTED,
135 JOURNAL_MAY_SKIP_FLUSH,
136 JOURNAL_NEED_FLUSH_WRITE,
137 JOURNAL_SPACE_LOW,
138};
139
140/* Reasons we may fail to get a journal reservation: */
141#define JOURNAL_ERRORS() \
142 x(ok) \
143 x(retry) \
144 x(blocked) \
145 x(max_in_flight) \
146 x(journal_full) \
147 x(journal_pin_full) \
148 x(journal_stuck) \
149 x(insufficient_devices)
150
151enum journal_errors {
152#define x(n) JOURNAL_ERR_##n,
153 JOURNAL_ERRORS()
154#undef x
155};
156
157typedef DARRAY(u64) darray_u64;
158
159struct journal_bio {
160 struct bch_dev *ca;
161 unsigned buf_idx;
162
163 struct bio bio;
164};
165
166/* Embedded in struct bch_fs */
167struct journal {
168 /* Fastpath stuff up front: */
169 struct {
170
171 union journal_res_state reservations;
172 enum bch_watermark watermark;
173
174 } __aligned(SMP_CACHE_BYTES);
175
176 unsigned long flags;
177
178 /* Max size of current journal entry */
179 unsigned cur_entry_u64s;
180 unsigned cur_entry_sectors;
181
182 /* Reserved space in journal entry to be used just prior to write */
183 unsigned entry_u64s_reserved;
184
185
186 /*
187 * 0, or -ENOSPC if waiting on journal reclaim, or -EROFS if
188 * insufficient devices:
189 */
190 enum journal_errors cur_entry_error;
191
192 unsigned buf_size_want;
193 /*
194 * We may queue up some things to be journalled (log messages) before
195 * the journal has actually started - stash them here:
196 */
197 darray_u64 early_journal_entries;
198
199 /*
200 * Protects journal_buf->data, when accessing without a jorunal
201 * reservation: for synchronization between the btree write buffer code
202 * and the journal write path:
203 */
204 struct mutex buf_lock;
205 /*
206 * Two journal entries -- one is currently open for new entries, the
207 * other is possibly being written out.
208 */
209 struct journal_buf buf[JOURNAL_BUF_NR];
210
211 spinlock_t lock;
212
213 /* if nonzero, we may not open a new journal entry: */
214 unsigned blocked;
215
216 /* Used when waiting because the journal was full */
217 wait_queue_head_t wait;
218 struct closure_waitlist async_wait;
219
220 struct delayed_work write_work;
221 struct workqueue_struct *wq;
222
223 /* Sequence number of most recent journal entry (last entry in @pin) */
224 atomic64_t seq;
225
226 /* seq, last_seq from the most recent journal entry successfully written */
227 u64 seq_ondisk;
228 u64 flushed_seq_ondisk;
229 u64 last_seq_ondisk;
230 u64 err_seq;
231 u64 last_empty_seq;
232
233 /*
234 * FIFO of journal entries whose btree updates have not yet been
235 * written out.
236 *
237 * Each entry is a reference count. The position in the FIFO is the
238 * entry's sequence number relative to @seq.
239 *
240 * The journal entry itself holds a reference count, put when the
241 * journal entry is written out. Each btree node modified by the journal
242 * entry also holds a reference count, put when the btree node is
243 * written.
244 *
245 * When a reference count reaches zero, the journal entry is no longer
246 * needed. When all journal entries in the oldest journal bucket are no
247 * longer needed, the bucket can be discarded and reused.
248 */
249 struct {
250 u64 front, back, size, mask;
251 struct journal_entry_pin_list *data;
252 } pin;
253
254 struct journal_space space[journal_space_nr];
255
256 u64 replay_journal_seq;
257 u64 replay_journal_seq_end;
258
259 struct write_point wp;
260 spinlock_t err_lock;
261
262 struct mutex reclaim_lock;
263 /*
264 * Used for waiting until journal reclaim has freed up space in the
265 * journal:
266 */
267 wait_queue_head_t reclaim_wait;
268 struct task_struct *reclaim_thread;
269 bool reclaim_kicked;
270 unsigned long next_reclaim;
271 u64 nr_direct_reclaim;
272 u64 nr_background_reclaim;
273
274 unsigned long last_flushed;
275 struct journal_entry_pin *flush_in_progress;
276 bool flush_in_progress_dropped;
277 wait_queue_head_t pin_flush_wait;
278
279 /* protects advancing ja->discard_idx: */
280 struct mutex discard_lock;
281 bool can_discard;
282
283 unsigned long last_flush_write;
284
285 u64 write_start_time;
286
287 u64 nr_flush_writes;
288 u64 nr_noflush_writes;
289 u64 entry_bytes_written;
290
291 struct bch2_time_stats *flush_write_time;
292 struct bch2_time_stats *noflush_write_time;
293 struct bch2_time_stats *flush_seq_time;
294
295#ifdef CONFIG_DEBUG_LOCK_ALLOC
296 struct lockdep_map res_map;
297#endif
298} __aligned(SMP_CACHE_BYTES);
299
300/*
301 * Embedded in struct bch_dev. First three fields refer to the array of journal
302 * buckets, in bch_sb.
303 */
304struct journal_device {
305 /*
306 * For each journal bucket, contains the max sequence number of the
307 * journal writes it contains - so we know when a bucket can be reused.
308 */
309 u64 *bucket_seq;
310
311 unsigned sectors_free;
312
313 /*
314 * discard_idx <= dirty_idx_ondisk <= dirty_idx <= cur_idx:
315 */
316 unsigned discard_idx; /* Next bucket to discard */
317 unsigned dirty_idx_ondisk;
318 unsigned dirty_idx;
319 unsigned cur_idx; /* Journal bucket we're currently writing to */
320 unsigned nr;
321
322 u64 *buckets;
323
324 /* Bio for journal reads/writes to this device */
325 struct journal_bio *bio[JOURNAL_BUF_NR];
326
327 /* for bch_journal_read_device */
328 struct closure read;
329};
330
331/*
332 * journal_entry_res - reserve space in every journal entry:
333 */
334struct journal_entry_res {
335 unsigned u64s;
336};
337
338#endif /* _BCACHEFS_JOURNAL_TYPES_H */
339

source code of linux/fs/bcachefs/journal_types.h