1// SPDX-License-Identifier: GPL-2.0
2/*
3 * bcache sysfs interfaces
4 *
5 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
6 * Copyright 2012 Google, Inc.
7 */
8
9#include "bcache.h"
10#include "sysfs.h"
11#include "btree.h"
12#include "request.h"
13#include "writeback.h"
14#include "features.h"
15
16#include <linux/blkdev.h>
17#include <linux/sort.h>
18#include <linux/sched/clock.h>
19
20extern bool bcache_is_reboot;
21
22/* Default is 0 ("writethrough") */
23static const char * const bch_cache_modes[] = {
24 "writethrough",
25 "writeback",
26 "writearound",
27 "none",
28 NULL
29};
30
31static const char * const bch_reada_cache_policies[] = {
32 "all",
33 "meta-only",
34 NULL
35};
36
37/* Default is 0 ("auto") */
38static const char * const bch_stop_on_failure_modes[] = {
39 "auto",
40 "always",
41 NULL
42};
43
44static const char * const cache_replacement_policies[] = {
45 "lru",
46 "fifo",
47 "random",
48 NULL
49};
50
51static const char * const error_actions[] = {
52 "unregister",
53 "panic",
54 NULL
55};
56
57write_attribute(attach);
58write_attribute(detach);
59write_attribute(unregister);
60write_attribute(stop);
61write_attribute(clear_stats);
62write_attribute(trigger_gc);
63write_attribute(prune_cache);
64write_attribute(flash_vol_create);
65
66read_attribute(bucket_size);
67read_attribute(block_size);
68read_attribute(nbuckets);
69read_attribute(tree_depth);
70read_attribute(root_usage_percent);
71read_attribute(priority_stats);
72read_attribute(btree_cache_size);
73read_attribute(btree_cache_max_chain);
74read_attribute(cache_available_percent);
75read_attribute(written);
76read_attribute(btree_written);
77read_attribute(metadata_written);
78read_attribute(active_journal_entries);
79read_attribute(backing_dev_name);
80read_attribute(backing_dev_uuid);
81
82sysfs_time_stats_attribute(btree_gc, sec, ms);
83sysfs_time_stats_attribute(btree_split, sec, us);
84sysfs_time_stats_attribute(btree_sort, ms, us);
85sysfs_time_stats_attribute(btree_read, ms, us);
86
87read_attribute(btree_nodes);
88read_attribute(btree_used_percent);
89read_attribute(average_key_size);
90read_attribute(dirty_data);
91read_attribute(bset_tree_stats);
92read_attribute(feature_compat);
93read_attribute(feature_ro_compat);
94read_attribute(feature_incompat);
95
96read_attribute(state);
97read_attribute(cache_read_races);
98read_attribute(reclaim);
99read_attribute(reclaimed_journal_buckets);
100read_attribute(flush_write);
101read_attribute(writeback_keys_done);
102read_attribute(writeback_keys_failed);
103read_attribute(io_errors);
104read_attribute(congested);
105read_attribute(cutoff_writeback);
106read_attribute(cutoff_writeback_sync);
107rw_attribute(congested_read_threshold_us);
108rw_attribute(congested_write_threshold_us);
109
110rw_attribute(sequential_cutoff);
111rw_attribute(data_csum);
112rw_attribute(cache_mode);
113rw_attribute(readahead_cache_policy);
114rw_attribute(stop_when_cache_set_failed);
115rw_attribute(writeback_metadata);
116rw_attribute(writeback_running);
117rw_attribute(writeback_percent);
118rw_attribute(writeback_delay);
119rw_attribute(writeback_rate);
120rw_attribute(writeback_consider_fragment);
121
122rw_attribute(writeback_rate_update_seconds);
123rw_attribute(writeback_rate_i_term_inverse);
124rw_attribute(writeback_rate_p_term_inverse);
125rw_attribute(writeback_rate_fp_term_low);
126rw_attribute(writeback_rate_fp_term_mid);
127rw_attribute(writeback_rate_fp_term_high);
128rw_attribute(writeback_rate_minimum);
129read_attribute(writeback_rate_debug);
130
131read_attribute(stripe_size);
132read_attribute(partial_stripes_expensive);
133
134rw_attribute(synchronous);
135rw_attribute(journal_delay_ms);
136rw_attribute(io_disable);
137rw_attribute(discard);
138rw_attribute(running);
139rw_attribute(label);
140rw_attribute(errors);
141rw_attribute(io_error_limit);
142rw_attribute(io_error_halflife);
143rw_attribute(verify);
144rw_attribute(bypass_torture_test);
145rw_attribute(key_merging_disabled);
146rw_attribute(gc_always_rewrite);
147rw_attribute(expensive_debug_checks);
148rw_attribute(cache_replacement_policy);
149rw_attribute(btree_shrinker_disabled);
150rw_attribute(copy_gc_enabled);
151rw_attribute(idle_max_writeback_rate);
152rw_attribute(gc_after_writeback);
153rw_attribute(size);
154
155static ssize_t bch_snprint_string_list(char *buf,
156 size_t size,
157 const char * const list[],
158 size_t selected)
159{
160 char *out = buf;
161 size_t i;
162
163 for (i = 0; list[i]; i++)
164 out += scnprintf(buf: out, size: buf + size - out,
165 fmt: i == selected ? "[%s] " : "%s ", list[i]);
166
167 out[-1] = '\n';
168 return out - buf;
169}
170
171SHOW(__bch_cached_dev)
172{
173 struct cached_dev *dc = container_of(kobj, struct cached_dev,
174 disk.kobj);
175 char const *states[] = { "no cache", "clean", "dirty", "inconsistent" };
176 int wb = dc->writeback_running;
177
178#define var(stat) (dc->stat)
179
180 if (attr == &sysfs_cache_mode)
181 return bch_snprint_string_list(buf, PAGE_SIZE,
182 list: bch_cache_modes,
183 selected: BDEV_CACHE_MODE(k: &dc->sb));
184
185 if (attr == &sysfs_readahead_cache_policy)
186 return bch_snprint_string_list(buf, PAGE_SIZE,
187 list: bch_reada_cache_policies,
188 selected: dc->cache_readahead_policy);
189
190 if (attr == &sysfs_stop_when_cache_set_failed)
191 return bch_snprint_string_list(buf, PAGE_SIZE,
192 list: bch_stop_on_failure_modes,
193 selected: dc->stop_when_cache_set_failed);
194
195
196 sysfs_printf(data_csum, "%i", dc->disk.data_csum);
197 var_printf(verify, "%i");
198 var_printf(bypass_torture_test, "%i");
199 var_printf(writeback_metadata, "%i");
200 var_printf(writeback_running, "%i");
201 var_printf(writeback_consider_fragment, "%i");
202 var_print(writeback_delay);
203 var_print(writeback_percent);
204 sysfs_hprint(writeback_rate,
205 wb ? atomic_long_read(&dc->writeback_rate.rate) << 9 : 0);
206 sysfs_printf(io_errors, "%i", atomic_read(&dc->io_errors));
207 sysfs_printf(io_error_limit, "%i", dc->error_limit);
208 sysfs_printf(io_disable, "%i", dc->io_disable);
209 var_print(writeback_rate_update_seconds);
210 var_print(writeback_rate_i_term_inverse);
211 var_print(writeback_rate_p_term_inverse);
212 var_print(writeback_rate_fp_term_low);
213 var_print(writeback_rate_fp_term_mid);
214 var_print(writeback_rate_fp_term_high);
215 var_print(writeback_rate_minimum);
216
217 if (attr == &sysfs_writeback_rate_debug) {
218 char rate[20];
219 char dirty[20];
220 char target[20];
221 char proportional[20];
222 char integral[20];
223 char change[20];
224 s64 next_io;
225
226 /*
227 * Except for dirty and target, other values should
228 * be 0 if writeback is not running.
229 */
230 bch_hprint(buf: rate,
231 v: wb ? atomic_long_read(v: &dc->writeback_rate.rate) << 9
232 : 0);
233 bch_hprint(buf: dirty, v: bcache_dev_sectors_dirty(d: &dc->disk) << 9);
234 bch_hprint(buf: target, v: dc->writeback_rate_target << 9);
235 bch_hprint(buf: proportional,
236 v: wb ? dc->writeback_rate_proportional << 9 : 0);
237 bch_hprint(buf: integral,
238 v: wb ? dc->writeback_rate_integral_scaled << 9 : 0);
239 bch_hprint(buf: change, v: wb ? dc->writeback_rate_change << 9 : 0);
240 next_io = wb ? div64_s64(dividend: dc->writeback_rate.next-local_clock(),
241 NSEC_PER_MSEC) : 0;
242
243 return sprintf(buf,
244 fmt: "rate:\t\t%s/sec\n"
245 "dirty:\t\t%s\n"
246 "target:\t\t%s\n"
247 "proportional:\t%s\n"
248 "integral:\t%s\n"
249 "change:\t\t%s/sec\n"
250 "next io:\t%llims\n",
251 rate, dirty, target, proportional,
252 integral, change, next_io);
253 }
254
255 sysfs_hprint(dirty_data,
256 bcache_dev_sectors_dirty(&dc->disk) << 9);
257
258 sysfs_hprint(stripe_size, ((uint64_t)dc->disk.stripe_size) << 9);
259 var_printf(partial_stripes_expensive, "%u");
260
261 var_hprint(sequential_cutoff);
262
263 sysfs_print(running, atomic_read(&dc->running));
264 sysfs_print(state, states[BDEV_STATE(&dc->sb)]);
265
266 if (attr == &sysfs_label) {
267 memcpy(buf, dc->sb.label, SB_LABEL_SIZE);
268 buf[SB_LABEL_SIZE + 1] = '\0';
269 strcat(p: buf, q: "\n");
270 return strlen(buf);
271 }
272
273 if (attr == &sysfs_backing_dev_name) {
274 snprintf(buf, BDEVNAME_SIZE + 1, fmt: "%pg", dc->bdev);
275 strcat(p: buf, q: "\n");
276 return strlen(buf);
277 }
278
279 if (attr == &sysfs_backing_dev_uuid) {
280 /* convert binary uuid into 36-byte string plus '\0' */
281 snprintf(buf, size: 36+1, fmt: "%pU", dc->sb.uuid);
282 strcat(p: buf, q: "\n");
283 return strlen(buf);
284 }
285
286#undef var
287 return 0;
288}
289SHOW_LOCKED(bch_cached_dev)
290
291STORE(__cached_dev)
292{
293 struct cached_dev *dc = container_of(kobj, struct cached_dev,
294 disk.kobj);
295 ssize_t v;
296 struct cache_set *c;
297 struct kobj_uevent_env *env;
298
299 /* no user space access if system is rebooting */
300 if (bcache_is_reboot)
301 return -EBUSY;
302
303#define d_strtoul(var) sysfs_strtoul(var, dc->var)
304#define d_strtoul_nonzero(var) sysfs_strtoul_clamp(var, dc->var, 1, INT_MAX)
305#define d_strtoi_h(var) sysfs_hatoi(var, dc->var)
306
307 sysfs_strtoul(data_csum, dc->disk.data_csum);
308 d_strtoul(verify);
309 sysfs_strtoul_bool(bypass_torture_test, dc->bypass_torture_test);
310 sysfs_strtoul_bool(writeback_metadata, dc->writeback_metadata);
311 sysfs_strtoul_bool(writeback_running, dc->writeback_running);
312 sysfs_strtoul_bool(writeback_consider_fragment, dc->writeback_consider_fragment);
313 sysfs_strtoul_clamp(writeback_delay, dc->writeback_delay, 0, UINT_MAX);
314
315 sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent,
316 0, bch_cutoff_writeback);
317
318 if (attr == &sysfs_writeback_rate) {
319 ssize_t ret;
320 long int v = atomic_long_read(v: &dc->writeback_rate.rate);
321
322 ret = strtoul_safe_clamp(buf, v, 1, INT_MAX);
323
324 if (!ret) {
325 atomic_long_set(v: &dc->writeback_rate.rate, i: v);
326 ret = size;
327 }
328
329 return ret;
330 }
331
332 sysfs_strtoul_clamp(writeback_rate_update_seconds,
333 dc->writeback_rate_update_seconds,
334 1, WRITEBACK_RATE_UPDATE_SECS_MAX);
335 sysfs_strtoul_clamp(writeback_rate_i_term_inverse,
336 dc->writeback_rate_i_term_inverse,
337 1, UINT_MAX);
338 sysfs_strtoul_clamp(writeback_rate_p_term_inverse,
339 dc->writeback_rate_p_term_inverse,
340 1, UINT_MAX);
341 sysfs_strtoul_clamp(writeback_rate_fp_term_low,
342 dc->writeback_rate_fp_term_low,
343 1, dc->writeback_rate_fp_term_mid - 1);
344 sysfs_strtoul_clamp(writeback_rate_fp_term_mid,
345 dc->writeback_rate_fp_term_mid,
346 dc->writeback_rate_fp_term_low + 1,
347 dc->writeback_rate_fp_term_high - 1);
348 sysfs_strtoul_clamp(writeback_rate_fp_term_high,
349 dc->writeback_rate_fp_term_high,
350 dc->writeback_rate_fp_term_mid + 1, UINT_MAX);
351 sysfs_strtoul_clamp(writeback_rate_minimum,
352 dc->writeback_rate_minimum,
353 1, UINT_MAX);
354
355 sysfs_strtoul_clamp(io_error_limit, dc->error_limit, 0, INT_MAX);
356
357 if (attr == &sysfs_io_disable) {
358 int v = strtoul_or_return(buf);
359
360 dc->io_disable = v ? 1 : 0;
361 }
362
363 sysfs_strtoul_clamp(sequential_cutoff,
364 dc->sequential_cutoff,
365 0, UINT_MAX);
366
367 if (attr == &sysfs_clear_stats)
368 bch_cache_accounting_clear(acc: &dc->accounting);
369
370 if (attr == &sysfs_running &&
371 strtoul_or_return(buf)) {
372 v = bch_cached_dev_run(dc);
373 if (v)
374 return v;
375 }
376
377 if (attr == &sysfs_cache_mode) {
378 v = __sysfs_match_string(array: bch_cache_modes, n: -1, s: buf);
379 if (v < 0)
380 return v;
381
382 if ((unsigned int) v != BDEV_CACHE_MODE(k: &dc->sb)) {
383 SET_BDEV_CACHE_MODE(k: &dc->sb, v);
384 bch_write_bdev_super(dc, NULL);
385 }
386 }
387
388 if (attr == &sysfs_readahead_cache_policy) {
389 v = __sysfs_match_string(array: bch_reada_cache_policies, n: -1, s: buf);
390 if (v < 0)
391 return v;
392
393 if ((unsigned int) v != dc->cache_readahead_policy)
394 dc->cache_readahead_policy = v;
395 }
396
397 if (attr == &sysfs_stop_when_cache_set_failed) {
398 v = __sysfs_match_string(array: bch_stop_on_failure_modes, n: -1, s: buf);
399 if (v < 0)
400 return v;
401
402 dc->stop_when_cache_set_failed = v;
403 }
404
405 if (attr == &sysfs_label) {
406 if (size > SB_LABEL_SIZE)
407 return -EINVAL;
408 memcpy(dc->sb.label, buf, size);
409 if (size < SB_LABEL_SIZE)
410 dc->sb.label[size] = '\0';
411 if (size && dc->sb.label[size - 1] == '\n')
412 dc->sb.label[size - 1] = '\0';
413 bch_write_bdev_super(dc, NULL);
414 if (dc->disk.c) {
415 memcpy(dc->disk.c->uuids[dc->disk.id].label,
416 buf, SB_LABEL_SIZE);
417 bch_uuid_write(c: dc->disk.c);
418 }
419 env = kzalloc(size: sizeof(struct kobj_uevent_env), GFP_KERNEL);
420 if (!env)
421 return -ENOMEM;
422 add_uevent_var(env, format: "DRIVER=bcache");
423 add_uevent_var(env, format: "CACHED_UUID=%pU", dc->sb.uuid);
424 add_uevent_var(env, format: "CACHED_LABEL=%s", buf);
425 kobject_uevent_env(kobj: &disk_to_dev(dc->disk.disk)->kobj,
426 action: KOBJ_CHANGE,
427 envp: env->envp);
428 kfree(objp: env);
429 }
430
431 if (attr == &sysfs_attach) {
432 uint8_t set_uuid[16];
433
434 if (bch_parse_uuid(s: buf, uuid: set_uuid) < 16)
435 return -EINVAL;
436
437 v = -ENOENT;
438 list_for_each_entry(c, &bch_cache_sets, list) {
439 v = bch_cached_dev_attach(dc, c, set_uuid);
440 if (!v)
441 return size;
442 }
443 if (v == -ENOENT)
444 pr_err("Can't attach %s: cache set not found\n", buf);
445 return v;
446 }
447
448 if (attr == &sysfs_detach && dc->disk.c)
449 bch_cached_dev_detach(dc);
450
451 if (attr == &sysfs_stop)
452 bcache_device_stop(d: &dc->disk);
453
454 return size;
455}
456
457STORE(bch_cached_dev)
458{
459 struct cached_dev *dc = container_of(kobj, struct cached_dev,
460 disk.kobj);
461
462 /* no user space access if system is rebooting */
463 if (bcache_is_reboot)
464 return -EBUSY;
465
466 mutex_lock(&bch_register_lock);
467 size = __cached_dev_store(kobj, attr, buf, size);
468
469 if (attr == &sysfs_writeback_running) {
470 /* dc->writeback_running changed in __cached_dev_store() */
471 if (IS_ERR_OR_NULL(ptr: dc->writeback_thread)) {
472 /*
473 * reject setting it to 1 via sysfs if writeback
474 * kthread is not created yet.
475 */
476 if (dc->writeback_running) {
477 dc->writeback_running = false;
478 pr_err("%s: failed to run non-existent writeback thread\n",
479 dc->disk.disk->disk_name);
480 }
481 } else
482 /*
483 * writeback kthread will check if dc->writeback_running
484 * is true or false.
485 */
486 bch_writeback_queue(dc);
487 }
488
489 /*
490 * Only set BCACHE_DEV_WB_RUNNING when cached device attached to
491 * a cache set, otherwise it doesn't make sense.
492 */
493 if (attr == &sysfs_writeback_percent)
494 if ((dc->disk.c != NULL) &&
495 (!test_and_set_bit(BCACHE_DEV_WB_RUNNING, addr: &dc->disk.flags)))
496 schedule_delayed_work(dwork: &dc->writeback_rate_update,
497 delay: dc->writeback_rate_update_seconds * HZ);
498
499 mutex_unlock(lock: &bch_register_lock);
500 return size;
501}
502
503static struct attribute *bch_cached_dev_attrs[] = {
504 &sysfs_attach,
505 &sysfs_detach,
506 &sysfs_stop,
507#if 0
508 &sysfs_data_csum,
509#endif
510 &sysfs_cache_mode,
511 &sysfs_readahead_cache_policy,
512 &sysfs_stop_when_cache_set_failed,
513 &sysfs_writeback_metadata,
514 &sysfs_writeback_running,
515 &sysfs_writeback_delay,
516 &sysfs_writeback_percent,
517 &sysfs_writeback_rate,
518 &sysfs_writeback_consider_fragment,
519 &sysfs_writeback_rate_update_seconds,
520 &sysfs_writeback_rate_i_term_inverse,
521 &sysfs_writeback_rate_p_term_inverse,
522 &sysfs_writeback_rate_fp_term_low,
523 &sysfs_writeback_rate_fp_term_mid,
524 &sysfs_writeback_rate_fp_term_high,
525 &sysfs_writeback_rate_minimum,
526 &sysfs_writeback_rate_debug,
527 &sysfs_io_errors,
528 &sysfs_io_error_limit,
529 &sysfs_io_disable,
530 &sysfs_dirty_data,
531 &sysfs_stripe_size,
532 &sysfs_partial_stripes_expensive,
533 &sysfs_sequential_cutoff,
534 &sysfs_clear_stats,
535 &sysfs_running,
536 &sysfs_state,
537 &sysfs_label,
538#ifdef CONFIG_BCACHE_DEBUG
539 &sysfs_verify,
540 &sysfs_bypass_torture_test,
541#endif
542 &sysfs_backing_dev_name,
543 &sysfs_backing_dev_uuid,
544 NULL
545};
546ATTRIBUTE_GROUPS(bch_cached_dev);
547KTYPE(bch_cached_dev);
548
549SHOW(bch_flash_dev)
550{
551 struct bcache_device *d = container_of(kobj, struct bcache_device,
552 kobj);
553 struct uuid_entry *u = &d->c->uuids[d->id];
554
555 sysfs_printf(data_csum, "%i", d->data_csum);
556 sysfs_hprint(size, u->sectors << 9);
557
558 if (attr == &sysfs_label) {
559 memcpy(buf, u->label, SB_LABEL_SIZE);
560 buf[SB_LABEL_SIZE + 1] = '\0';
561 strcat(p: buf, q: "\n");
562 return strlen(buf);
563 }
564
565 return 0;
566}
567
568STORE(__bch_flash_dev)
569{
570 struct bcache_device *d = container_of(kobj, struct bcache_device,
571 kobj);
572 struct uuid_entry *u = &d->c->uuids[d->id];
573
574 /* no user space access if system is rebooting */
575 if (bcache_is_reboot)
576 return -EBUSY;
577
578 sysfs_strtoul(data_csum, d->data_csum);
579
580 if (attr == &sysfs_size) {
581 uint64_t v;
582
583 strtoi_h_or_return(buf, v);
584
585 u->sectors = v >> 9;
586 bch_uuid_write(c: d->c);
587 set_capacity(disk: d->disk, size: u->sectors);
588 }
589
590 if (attr == &sysfs_label) {
591 memcpy(u->label, buf, SB_LABEL_SIZE);
592 bch_uuid_write(c: d->c);
593 }
594
595 if (attr == &sysfs_unregister) {
596 set_bit(BCACHE_DEV_DETACHING, addr: &d->flags);
597 bcache_device_stop(d);
598 }
599
600 return size;
601}
602STORE_LOCKED(bch_flash_dev)
603
604static struct attribute *bch_flash_dev_attrs[] = {
605 &sysfs_unregister,
606#if 0
607 &sysfs_data_csum,
608#endif
609 &sysfs_label,
610 &sysfs_size,
611 NULL
612};
613ATTRIBUTE_GROUPS(bch_flash_dev);
614KTYPE(bch_flash_dev);
615
616struct bset_stats_op {
617 struct btree_op op;
618 size_t nodes;
619 struct bset_stats stats;
620};
621
622static int bch_btree_bset_stats(struct btree_op *b_op, struct btree *b)
623{
624 struct bset_stats_op *op = container_of(b_op, struct bset_stats_op, op);
625
626 op->nodes++;
627 bch_btree_keys_stats(b: &b->keys, state: &op->stats);
628
629 return MAP_CONTINUE;
630}
631
632static int bch_bset_print_stats(struct cache_set *c, char *buf)
633{
634 struct bset_stats_op op;
635 int ret;
636
637 memset(&op, 0, sizeof(op));
638 bch_btree_op_init(op: &op.op, write_lock_level: -1);
639
640 ret = bch_btree_map_nodes(op: &op.op, c, from: &ZERO_KEY, fn: bch_btree_bset_stats);
641 if (ret < 0)
642 return ret;
643
644 return snprintf(buf, PAGE_SIZE,
645 fmt: "btree nodes: %zu\n"
646 "written sets: %zu\n"
647 "unwritten sets: %zu\n"
648 "written key bytes: %zu\n"
649 "unwritten key bytes: %zu\n"
650 "floats: %zu\n"
651 "failed: %zu\n",
652 op.nodes,
653 op.stats.sets_written, op.stats.sets_unwritten,
654 op.stats.bytes_written, op.stats.bytes_unwritten,
655 op.stats.floats, op.stats.failed);
656}
657
658static unsigned int bch_root_usage(struct cache_set *c)
659{
660 unsigned int bytes = 0;
661 struct bkey *k;
662 struct btree *b;
663 struct btree_iter iter;
664
665 goto lock_root;
666
667 do {
668 rw_unlock(w: false, b);
669lock_root:
670 b = c->root;
671 rw_lock(w: false, b, level: b->level);
672 } while (b != c->root);
673
674 for_each_key_filter(&b->keys, k, &iter, bch_ptr_bad)
675 bytes += bkey_bytes(k);
676
677 rw_unlock(w: false, b);
678
679 return (bytes * 100) / btree_bytes(c);
680}
681
682static size_t bch_cache_size(struct cache_set *c)
683{
684 size_t ret = 0;
685 struct btree *b;
686
687 mutex_lock(&c->bucket_lock);
688 list_for_each_entry(b, &c->btree_cache, list)
689 ret += 1 << (b->keys.page_order + PAGE_SHIFT);
690
691 mutex_unlock(lock: &c->bucket_lock);
692 return ret;
693}
694
695static unsigned int bch_cache_max_chain(struct cache_set *c)
696{
697 unsigned int ret = 0;
698 struct hlist_head *h;
699
700 mutex_lock(&c->bucket_lock);
701
702 for (h = c->bucket_hash;
703 h < c->bucket_hash + (1 << BUCKET_HASH_BITS);
704 h++) {
705 unsigned int i = 0;
706 struct hlist_node *p;
707
708 hlist_for_each(p, h)
709 i++;
710
711 ret = max(ret, i);
712 }
713
714 mutex_unlock(lock: &c->bucket_lock);
715 return ret;
716}
717
718static unsigned int bch_btree_used(struct cache_set *c)
719{
720 return div64_u64(dividend: c->gc_stats.key_bytes * 100,
721 divisor: (c->gc_stats.nodes ?: 1) * btree_bytes(c));
722}
723
724static unsigned int bch_average_key_size(struct cache_set *c)
725{
726 return c->gc_stats.nkeys
727 ? div64_u64(dividend: c->gc_stats.data, divisor: c->gc_stats.nkeys)
728 : 0;
729}
730
731SHOW(__bch_cache_set)
732{
733 struct cache_set *c = container_of(kobj, struct cache_set, kobj);
734
735 sysfs_print(synchronous, CACHE_SYNC(&c->cache->sb));
736 sysfs_print(journal_delay_ms, c->journal_delay_ms);
737 sysfs_hprint(bucket_size, bucket_bytes(c->cache));
738 sysfs_hprint(block_size, block_bytes(c->cache));
739 sysfs_print(tree_depth, c->root->level);
740 sysfs_print(root_usage_percent, bch_root_usage(c));
741
742 sysfs_hprint(btree_cache_size, bch_cache_size(c));
743 sysfs_print(btree_cache_max_chain, bch_cache_max_chain(c));
744 sysfs_print(cache_available_percent, 100 - c->gc_stats.in_use);
745
746 sysfs_print_time_stats(&c->btree_gc_time, btree_gc, sec, ms);
747 sysfs_print_time_stats(&c->btree_split_time, btree_split, sec, us);
748 sysfs_print_time_stats(&c->sort.time, btree_sort, ms, us);
749 sysfs_print_time_stats(&c->btree_read_time, btree_read, ms, us);
750
751 sysfs_print(btree_used_percent, bch_btree_used(c));
752 sysfs_print(btree_nodes, c->gc_stats.nodes);
753 sysfs_hprint(average_key_size, bch_average_key_size(c));
754
755 sysfs_print(cache_read_races,
756 atomic_long_read(&c->cache_read_races));
757
758 sysfs_print(reclaim,
759 atomic_long_read(&c->reclaim));
760
761 sysfs_print(reclaimed_journal_buckets,
762 atomic_long_read(&c->reclaimed_journal_buckets));
763
764 sysfs_print(flush_write,
765 atomic_long_read(&c->flush_write));
766
767 sysfs_print(writeback_keys_done,
768 atomic_long_read(&c->writeback_keys_done));
769 sysfs_print(writeback_keys_failed,
770 atomic_long_read(&c->writeback_keys_failed));
771
772 if (attr == &sysfs_errors)
773 return bch_snprint_string_list(buf, PAGE_SIZE, list: error_actions,
774 selected: c->on_error);
775
776 /* See count_io_errors for why 88 */
777 sysfs_print(io_error_halflife, c->error_decay * 88);
778 sysfs_print(io_error_limit, c->error_limit);
779
780 sysfs_hprint(congested,
781 ((uint64_t) bch_get_congested(c)) << 9);
782 sysfs_print(congested_read_threshold_us,
783 c->congested_read_threshold_us);
784 sysfs_print(congested_write_threshold_us,
785 c->congested_write_threshold_us);
786
787 sysfs_print(cutoff_writeback, bch_cutoff_writeback);
788 sysfs_print(cutoff_writeback_sync, bch_cutoff_writeback_sync);
789
790 sysfs_print(active_journal_entries, fifo_used(&c->journal.pin));
791 sysfs_printf(verify, "%i", c->verify);
792 sysfs_printf(key_merging_disabled, "%i", c->key_merging_disabled);
793 sysfs_printf(expensive_debug_checks,
794 "%i", c->expensive_debug_checks);
795 sysfs_printf(gc_always_rewrite, "%i", c->gc_always_rewrite);
796 sysfs_printf(btree_shrinker_disabled, "%i", c->shrinker_disabled);
797 sysfs_printf(copy_gc_enabled, "%i", c->copy_gc_enabled);
798 sysfs_printf(idle_max_writeback_rate, "%i",
799 c->idle_max_writeback_rate_enabled);
800 sysfs_printf(gc_after_writeback, "%i", c->gc_after_writeback);
801 sysfs_printf(io_disable, "%i",
802 test_bit(CACHE_SET_IO_DISABLE, &c->flags));
803
804 if (attr == &sysfs_bset_tree_stats)
805 return bch_bset_print_stats(c, buf);
806
807 if (attr == &sysfs_feature_compat)
808 return bch_print_cache_set_feature_compat(c, buf, PAGE_SIZE);
809 if (attr == &sysfs_feature_ro_compat)
810 return bch_print_cache_set_feature_ro_compat(c, buf, PAGE_SIZE);
811 if (attr == &sysfs_feature_incompat)
812 return bch_print_cache_set_feature_incompat(c, buf, PAGE_SIZE);
813
814 return 0;
815}
816SHOW_LOCKED(bch_cache_set)
817
818STORE(__bch_cache_set)
819{
820 struct cache_set *c = container_of(kobj, struct cache_set, kobj);
821 ssize_t v;
822
823 /* no user space access if system is rebooting */
824 if (bcache_is_reboot)
825 return -EBUSY;
826
827 if (attr == &sysfs_unregister)
828 bch_cache_set_unregister(c);
829
830 if (attr == &sysfs_stop)
831 bch_cache_set_stop(c);
832
833 if (attr == &sysfs_synchronous) {
834 bool sync = strtoul_or_return(buf);
835
836 if (sync != CACHE_SYNC(k: &c->cache->sb)) {
837 SET_CACHE_SYNC(k: &c->cache->sb, v: sync);
838 bcache_write_super(c);
839 }
840 }
841
842 if (attr == &sysfs_flash_vol_create) {
843 int r;
844 uint64_t v;
845
846 strtoi_h_or_return(buf, v);
847
848 r = bch_flash_dev_create(c, size: v);
849 if (r)
850 return r;
851 }
852
853 if (attr == &sysfs_clear_stats) {
854 atomic_long_set(v: &c->writeback_keys_done, i: 0);
855 atomic_long_set(v: &c->writeback_keys_failed, i: 0);
856
857 memset(&c->gc_stats, 0, sizeof(struct gc_stat));
858 bch_cache_accounting_clear(acc: &c->accounting);
859 }
860
861 if (attr == &sysfs_trigger_gc)
862 force_wake_up_gc(c);
863
864 if (attr == &sysfs_prune_cache) {
865 struct shrink_control sc;
866
867 sc.gfp_mask = GFP_KERNEL;
868 sc.nr_to_scan = strtoul_or_return(buf);
869 if (c->shrink)
870 c->shrink->scan_objects(c->shrink, &sc);
871 }
872
873 sysfs_strtoul_clamp(congested_read_threshold_us,
874 c->congested_read_threshold_us,
875 0, UINT_MAX);
876 sysfs_strtoul_clamp(congested_write_threshold_us,
877 c->congested_write_threshold_us,
878 0, UINT_MAX);
879
880 if (attr == &sysfs_errors) {
881 v = __sysfs_match_string(array: error_actions, n: -1, s: buf);
882 if (v < 0)
883 return v;
884
885 c->on_error = v;
886 }
887
888 sysfs_strtoul_clamp(io_error_limit, c->error_limit, 0, UINT_MAX);
889
890 /* See count_io_errors() for why 88 */
891 if (attr == &sysfs_io_error_halflife) {
892 unsigned long v = 0;
893 ssize_t ret;
894
895 ret = strtoul_safe_clamp(buf, v, 0, UINT_MAX);
896 if (!ret) {
897 c->error_decay = v / 88;
898 return size;
899 }
900 return ret;
901 }
902
903 if (attr == &sysfs_io_disable) {
904 v = strtoul_or_return(buf);
905 if (v) {
906 if (test_and_set_bit(CACHE_SET_IO_DISABLE,
907 addr: &c->flags))
908 pr_warn("CACHE_SET_IO_DISABLE already set\n");
909 } else {
910 if (!test_and_clear_bit(CACHE_SET_IO_DISABLE,
911 addr: &c->flags))
912 pr_warn("CACHE_SET_IO_DISABLE already cleared\n");
913 }
914 }
915
916 sysfs_strtoul_clamp(journal_delay_ms,
917 c->journal_delay_ms,
918 0, USHRT_MAX);
919 sysfs_strtoul_bool(verify, c->verify);
920 sysfs_strtoul_bool(key_merging_disabled, c->key_merging_disabled);
921 sysfs_strtoul(expensive_debug_checks, c->expensive_debug_checks);
922 sysfs_strtoul_bool(gc_always_rewrite, c->gc_always_rewrite);
923 sysfs_strtoul_bool(btree_shrinker_disabled, c->shrinker_disabled);
924 sysfs_strtoul_bool(copy_gc_enabled, c->copy_gc_enabled);
925 sysfs_strtoul_bool(idle_max_writeback_rate,
926 c->idle_max_writeback_rate_enabled);
927
928 /*
929 * write gc_after_writeback here may overwrite an already set
930 * BCH_DO_AUTO_GC, it doesn't matter because this flag will be
931 * set in next chance.
932 */
933 sysfs_strtoul_clamp(gc_after_writeback, c->gc_after_writeback, 0, 1);
934
935 return size;
936}
937STORE_LOCKED(bch_cache_set)
938
939SHOW(bch_cache_set_internal)
940{
941 struct cache_set *c = container_of(kobj, struct cache_set, internal);
942
943 return bch_cache_set_show(kobj: &c->kobj, attr, buf);
944}
945
946STORE(bch_cache_set_internal)
947{
948 struct cache_set *c = container_of(kobj, struct cache_set, internal);
949
950 /* no user space access if system is rebooting */
951 if (bcache_is_reboot)
952 return -EBUSY;
953
954 return bch_cache_set_store(kobj: &c->kobj, attr, buf, size);
955}
956
957static void bch_cache_set_internal_release(struct kobject *k)
958{
959}
960
961static struct attribute *bch_cache_set_attrs[] = {
962 &sysfs_unregister,
963 &sysfs_stop,
964 &sysfs_synchronous,
965 &sysfs_journal_delay_ms,
966 &sysfs_flash_vol_create,
967
968 &sysfs_bucket_size,
969 &sysfs_block_size,
970 &sysfs_tree_depth,
971 &sysfs_root_usage_percent,
972 &sysfs_btree_cache_size,
973 &sysfs_cache_available_percent,
974
975 &sysfs_average_key_size,
976
977 &sysfs_errors,
978 &sysfs_io_error_limit,
979 &sysfs_io_error_halflife,
980 &sysfs_congested,
981 &sysfs_congested_read_threshold_us,
982 &sysfs_congested_write_threshold_us,
983 &sysfs_clear_stats,
984 NULL
985};
986ATTRIBUTE_GROUPS(bch_cache_set);
987KTYPE(bch_cache_set);
988
989static struct attribute *bch_cache_set_internal_attrs[] = {
990 &sysfs_active_journal_entries,
991
992 sysfs_time_stats_attribute_list(btree_gc, sec, ms)
993 sysfs_time_stats_attribute_list(btree_split, sec, us)
994 sysfs_time_stats_attribute_list(btree_sort, ms, us)
995 sysfs_time_stats_attribute_list(btree_read, ms, us)
996
997 &sysfs_btree_nodes,
998 &sysfs_btree_used_percent,
999 &sysfs_btree_cache_max_chain,
1000
1001 &sysfs_bset_tree_stats,
1002 &sysfs_cache_read_races,
1003 &sysfs_reclaim,
1004 &sysfs_reclaimed_journal_buckets,
1005 &sysfs_flush_write,
1006 &sysfs_writeback_keys_done,
1007 &sysfs_writeback_keys_failed,
1008
1009 &sysfs_trigger_gc,
1010 &sysfs_prune_cache,
1011#ifdef CONFIG_BCACHE_DEBUG
1012 &sysfs_verify,
1013 &sysfs_key_merging_disabled,
1014 &sysfs_expensive_debug_checks,
1015#endif
1016 &sysfs_gc_always_rewrite,
1017 &sysfs_btree_shrinker_disabled,
1018 &sysfs_copy_gc_enabled,
1019 &sysfs_idle_max_writeback_rate,
1020 &sysfs_gc_after_writeback,
1021 &sysfs_io_disable,
1022 &sysfs_cutoff_writeback,
1023 &sysfs_cutoff_writeback_sync,
1024 &sysfs_feature_compat,
1025 &sysfs_feature_ro_compat,
1026 &sysfs_feature_incompat,
1027 NULL
1028};
1029ATTRIBUTE_GROUPS(bch_cache_set_internal);
1030KTYPE(bch_cache_set_internal);
1031
1032static int __bch_cache_cmp(const void *l, const void *r)
1033{
1034 cond_resched();
1035 return *((uint16_t *)r) - *((uint16_t *)l);
1036}
1037
1038SHOW(__bch_cache)
1039{
1040 struct cache *ca = container_of(kobj, struct cache, kobj);
1041
1042 sysfs_hprint(bucket_size, bucket_bytes(ca));
1043 sysfs_hprint(block_size, block_bytes(ca));
1044 sysfs_print(nbuckets, ca->sb.nbuckets);
1045 sysfs_print(discard, ca->discard);
1046 sysfs_hprint(written, atomic_long_read(&ca->sectors_written) << 9);
1047 sysfs_hprint(btree_written,
1048 atomic_long_read(&ca->btree_sectors_written) << 9);
1049 sysfs_hprint(metadata_written,
1050 (atomic_long_read(&ca->meta_sectors_written) +
1051 atomic_long_read(&ca->btree_sectors_written)) << 9);
1052
1053 sysfs_print(io_errors,
1054 atomic_read(&ca->io_errors) >> IO_ERROR_SHIFT);
1055
1056 if (attr == &sysfs_cache_replacement_policy)
1057 return bch_snprint_string_list(buf, PAGE_SIZE,
1058 list: cache_replacement_policies,
1059 selected: CACHE_REPLACEMENT(k: &ca->sb));
1060
1061 if (attr == &sysfs_priority_stats) {
1062 struct bucket *b;
1063 size_t n = ca->sb.nbuckets, i;
1064 size_t unused = 0, available = 0, dirty = 0, meta = 0;
1065 uint64_t sum = 0;
1066 /* Compute 31 quantiles */
1067 uint16_t q[31], *p, *cached;
1068 ssize_t ret;
1069
1070 cached = p = vmalloc(array_size(sizeof(uint16_t),
1071 ca->sb.nbuckets));
1072 if (!p)
1073 return -ENOMEM;
1074
1075 mutex_lock(&ca->set->bucket_lock);
1076 for_each_bucket(b, ca) {
1077 if (!GC_SECTORS_USED(k: b))
1078 unused++;
1079 if (GC_MARK(k: b) == GC_MARK_RECLAIMABLE)
1080 available++;
1081 if (GC_MARK(k: b) == GC_MARK_DIRTY)
1082 dirty++;
1083 if (GC_MARK(k: b) == GC_MARK_METADATA)
1084 meta++;
1085 }
1086
1087 for (i = ca->sb.first_bucket; i < n; i++)
1088 p[i] = ca->buckets[i].prio;
1089 mutex_unlock(lock: &ca->set->bucket_lock);
1090
1091 sort(base: p, num: n, size: sizeof(uint16_t), cmp_func: __bch_cache_cmp, NULL);
1092
1093 while (n &&
1094 !cached[n - 1])
1095 --n;
1096
1097 while (cached < p + n &&
1098 *cached == BTREE_PRIO) {
1099 cached++;
1100 n--;
1101 }
1102
1103 for (i = 0; i < n; i++)
1104 sum += INITIAL_PRIO - cached[i];
1105
1106 if (n)
1107 do_div(sum, n);
1108
1109 for (i = 0; i < ARRAY_SIZE(q); i++)
1110 q[i] = INITIAL_PRIO - cached[n * (i + 1) /
1111 (ARRAY_SIZE(q) + 1)];
1112
1113 vfree(addr: p);
1114
1115 ret = sysfs_emit(buf,
1116 fmt: "Unused: %zu%%\n"
1117 "Clean: %zu%%\n"
1118 "Dirty: %zu%%\n"
1119 "Metadata: %zu%%\n"
1120 "Average: %llu\n"
1121 "Sectors per Q: %zu\n"
1122 "Quantiles: [",
1123 unused * 100 / (size_t) ca->sb.nbuckets,
1124 available * 100 / (size_t) ca->sb.nbuckets,
1125 dirty * 100 / (size_t) ca->sb.nbuckets,
1126 meta * 100 / (size_t) ca->sb.nbuckets, sum,
1127 n * ca->sb.bucket_size / (ARRAY_SIZE(q) + 1));
1128
1129 for (i = 0; i < ARRAY_SIZE(q); i++)
1130 ret += sysfs_emit_at(buf, at: ret, fmt: "%u ", q[i]);
1131 ret--;
1132
1133 ret += sysfs_emit_at(buf, at: ret, fmt: "]\n");
1134
1135 return ret;
1136 }
1137
1138 return 0;
1139}
1140SHOW_LOCKED(bch_cache)
1141
1142STORE(__bch_cache)
1143{
1144 struct cache *ca = container_of(kobj, struct cache, kobj);
1145 ssize_t v;
1146
1147 /* no user space access if system is rebooting */
1148 if (bcache_is_reboot)
1149 return -EBUSY;
1150
1151 if (attr == &sysfs_discard) {
1152 bool v = strtoul_or_return(buf);
1153
1154 if (bdev_max_discard_sectors(bdev: ca->bdev))
1155 ca->discard = v;
1156
1157 if (v != CACHE_DISCARD(k: &ca->sb)) {
1158 SET_CACHE_DISCARD(k: &ca->sb, v);
1159 bcache_write_super(c: ca->set);
1160 }
1161 }
1162
1163 if (attr == &sysfs_cache_replacement_policy) {
1164 v = __sysfs_match_string(array: cache_replacement_policies, n: -1, s: buf);
1165 if (v < 0)
1166 return v;
1167
1168 if ((unsigned int) v != CACHE_REPLACEMENT(k: &ca->sb)) {
1169 mutex_lock(&ca->set->bucket_lock);
1170 SET_CACHE_REPLACEMENT(k: &ca->sb, v);
1171 mutex_unlock(lock: &ca->set->bucket_lock);
1172
1173 bcache_write_super(c: ca->set);
1174 }
1175 }
1176
1177 if (attr == &sysfs_clear_stats) {
1178 atomic_long_set(v: &ca->sectors_written, i: 0);
1179 atomic_long_set(v: &ca->btree_sectors_written, i: 0);
1180 atomic_long_set(v: &ca->meta_sectors_written, i: 0);
1181 atomic_set(v: &ca->io_count, i: 0);
1182 atomic_set(v: &ca->io_errors, i: 0);
1183 }
1184
1185 return size;
1186}
1187STORE_LOCKED(bch_cache)
1188
1189static struct attribute *bch_cache_attrs[] = {
1190 &sysfs_bucket_size,
1191 &sysfs_block_size,
1192 &sysfs_nbuckets,
1193 &sysfs_priority_stats,
1194 &sysfs_discard,
1195 &sysfs_written,
1196 &sysfs_btree_written,
1197 &sysfs_metadata_written,
1198 &sysfs_io_errors,
1199 &sysfs_clear_stats,
1200 &sysfs_cache_replacement_policy,
1201 NULL
1202};
1203ATTRIBUTE_GROUPS(bch_cache);
1204KTYPE(bch_cache);
1205

source code of linux/drivers/md/bcache/sysfs.c