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1// SPDX-License-Identifier: GPL-2.02/*3 * bcache journalling code, for btree insertions4 *5 * Copyright 2012 Google, Inc.6 */7 8#include "bcache.h"9#include "btree.h"10#include "debug.h"11#include "extents.h"12 13#include <trace/events/bcache.h>14 15/*16 * Journal replay/recovery:17 *18 * This code is all driven from run_cache_set(); we first read the journal19 * entries, do some other stuff, then we mark all the keys in the journal20 * entries (same as garbage collection would), then we replay them - reinserting21 * them into the cache in precisely the same order as they appear in the22 * journal.23 *24 * We only journal keys that go in leaf nodes, which simplifies things quite a25 * bit.26 */27 28static void journal_read_endio(struct bio *bio)29{30 struct closure *cl = bio->bi_private;31 32 closure_put(cl);33}34 35static int journal_read_bucket(struct cache *ca, struct list_head *list,36 unsigned int bucket_index)37{38 struct journal_device *ja = &ca->journal;39 struct bio *bio = &ja->bio;40 41 struct journal_replay *i;42 struct jset *j, *data = ca->set->journal.w[0].data;43 struct closure cl;44 unsigned int len, left, offset = 0;45 int ret = 0;46 sector_t bucket = bucket_to_sector(ca->set, ca->sb.d[bucket_index]);47 48 closure_init_stack(&cl);49 50 pr_debug("reading %u\n", bucket_index);51 52 while (offset < ca->sb.bucket_size) {53reread: left = ca->sb.bucket_size - offset;54 len = min_t(unsigned int, left, PAGE_SECTORS << JSET_BITS);55 56 bio_reset(bio, ca->bdev, REQ_OP_READ);57 bio->bi_iter.bi_sector = bucket + offset;58 bio->bi_iter.bi_size = len << 9;59 60 bio->bi_end_io = journal_read_endio;61 bio->bi_private = &cl;62 bch_bio_map(bio, data);63 64 closure_bio_submit(ca->set, bio, &cl);65 closure_sync(&cl);66 67 /* This function could be simpler now since we no longer write68 * journal entries that overlap bucket boundaries; this means69 * the start of a bucket will always have a valid journal entry70 * if it has any journal entries at all.71 */72 73 j = data;74 while (len) {75 struct list_head *where;76 size_t blocks, bytes = set_bytes(j);77 78 if (j->magic != jset_magic(&ca->sb)) {79 pr_debug("%u: bad magic\n", bucket_index);80 return ret;81 }82 83 if (bytes > left << 9 ||84 bytes > PAGE_SIZE << JSET_BITS) {85 pr_info("%u: too big, %zu bytes, offset %u\n",86 bucket_index, bytes, offset);87 return ret;88 }89 90 if (bytes > len << 9)91 goto reread;92 93 if (j->csum != csum_set(j)) {94 pr_info("%u: bad csum, %zu bytes, offset %u\n",95 bucket_index, bytes, offset);96 return ret;97 }98 99 blocks = set_blocks(j, block_bytes(ca));100 101 /*102 * Nodes in 'list' are in linear increasing order of103 * i->j.seq, the node on head has the smallest (oldest)104 * journal seq, the node on tail has the biggest105 * (latest) journal seq.106 */107 108 /*109 * Check from the oldest jset for last_seq. If110 * i->j.seq < j->last_seq, it means the oldest jset111 * in list is expired and useless, remove it from112 * this list. Otherwise, j is a candidate jset for113 * further following checks.114 */115 while (!list_empty(list)) {116 i = list_first_entry(list,117 struct journal_replay, list);118 if (i->j.seq >= j->last_seq)119 break;120 list_del(&i->list);121 kfree(i);122 }123 124 /* iterate list in reverse order (from latest jset) */125 list_for_each_entry_reverse(i, list, list) {126 if (j->seq == i->j.seq)127 goto next_set;128 129 /*130 * if j->seq is less than any i->j.last_seq131 * in list, j is an expired and useless jset.132 */133 if (j->seq < i->j.last_seq)134 goto next_set;135 136 /*137 * 'where' points to first jset in list which138 * is elder then j.139 */140 if (j->seq > i->j.seq) {141 where = &i->list;142 goto add;143 }144 }145 146 where = list;147add:148 i = kmalloc(offsetof(struct journal_replay, j) +149 bytes, GFP_KERNEL);150 if (!i)151 return -ENOMEM;152 unsafe_memcpy(&i->j, j, bytes,153 /* "bytes" was calculated by set_bytes() above */);154 /* Add to the location after 'where' points to */155 list_add(&i->list, where);156 ret = 1;157 158 if (j->seq > ja->seq[bucket_index])159 ja->seq[bucket_index] = j->seq;160next_set:161 offset += blocks * ca->sb.block_size;162 len -= blocks * ca->sb.block_size;163 j = ((void *) j) + blocks * block_bytes(ca);164 }165 }166 167 return ret;168}169 170int bch_journal_read(struct cache_set *c, struct list_head *list)171{172#define read_bucket(b) \173 ({ \174 ret = journal_read_bucket(ca, list, b); \175 __set_bit(b, bitmap); \176 if (ret < 0) \177 return ret; \178 ret; \179 })180 181 struct cache *ca = c->cache;182 int ret = 0;183 struct journal_device *ja = &ca->journal;184 DECLARE_BITMAP(bitmap, SB_JOURNAL_BUCKETS);185 unsigned int i, l, r, m;186 uint64_t seq;187 188 bitmap_zero(bitmap, SB_JOURNAL_BUCKETS);189 pr_debug("%u journal buckets\n", ca->sb.njournal_buckets);190 191 /*192 * Read journal buckets ordered by golden ratio hash to quickly193 * find a sequence of buckets with valid journal entries194 */195 for (i = 0; i < ca->sb.njournal_buckets; i++) {196 /*197 * We must try the index l with ZERO first for198 * correctness due to the scenario that the journal199 * bucket is circular buffer which might have wrapped200 */201 l = (i * 2654435769U) % ca->sb.njournal_buckets;202 203 if (test_bit(l, bitmap))204 break;205 206 if (read_bucket(l))207 goto bsearch;208 }209 210 /*211 * If that fails, check all the buckets we haven't checked212 * already213 */214 pr_debug("falling back to linear search\n");215 216 for_each_clear_bit(l, bitmap, ca->sb.njournal_buckets)217 if (read_bucket(l))218 goto bsearch;219 220 /* no journal entries on this device? */221 if (l == ca->sb.njournal_buckets)222 goto out;223bsearch:224 BUG_ON(list_empty(list));225 226 /* Binary search */227 m = l;228 r = find_next_bit(bitmap, ca->sb.njournal_buckets, l + 1);229 pr_debug("starting binary search, l %u r %u\n", l, r);230 231 while (l + 1 < r) {232 seq = list_entry(list->prev, struct journal_replay,233 list)->j.seq;234 235 m = (l + r) >> 1;236 read_bucket(m);237 238 if (seq != list_entry(list->prev, struct journal_replay,239 list)->j.seq)240 l = m;241 else242 r = m;243 }244 245 /*246 * Read buckets in reverse order until we stop finding more247 * journal entries248 */249 pr_debug("finishing up: m %u njournal_buckets %u\n",250 m, ca->sb.njournal_buckets);251 l = m;252 253 while (1) {254 if (!l--)255 l = ca->sb.njournal_buckets - 1;256 257 if (l == m)258 break;259 260 if (test_bit(l, bitmap))261 continue;262 263 if (!read_bucket(l))264 break;265 }266 267 seq = 0;268 269 for (i = 0; i < ca->sb.njournal_buckets; i++)270 if (ja->seq[i] > seq) {271 seq = ja->seq[i];272 /*273 * When journal_reclaim() goes to allocate for274 * the first time, it'll use the bucket after275 * ja->cur_idx276 */277 ja->cur_idx = i;278 ja->last_idx = ja->discard_idx = (i + 1) %279 ca->sb.njournal_buckets;280 281 }282 283out:284 if (!list_empty(list))285 c->journal.seq = list_entry(list->prev,286 struct journal_replay,287 list)->j.seq;288 289 return 0;290#undef read_bucket291}292 293void bch_journal_mark(struct cache_set *c, struct list_head *list)294{295 atomic_t p = { 0 };296 struct bkey *k;297 struct journal_replay *i;298 struct journal *j = &c->journal;299 uint64_t last = j->seq;300 301 /*302 * journal.pin should never fill up - we never write a journal303 * entry when it would fill up. But if for some reason it does, we304 * iterate over the list in reverse order so that we can just skip that305 * refcount instead of bugging.306 */307 308 list_for_each_entry_reverse(i, list, list) {309 BUG_ON(last < i->j.seq);310 i->pin = NULL;311 312 while (last-- != i->j.seq)313 if (fifo_free(&j->pin) > 1) {314 fifo_push_front(&j->pin, p);315 atomic_set(&fifo_front(&j->pin), 0);316 }317 318 if (fifo_free(&j->pin) > 1) {319 fifo_push_front(&j->pin, p);320 i->pin = &fifo_front(&j->pin);321 atomic_set(i->pin, 1);322 }323 324 for (k = i->j.start;325 k < bset_bkey_last(&i->j);326 k = bkey_next(k))327 if (!__bch_extent_invalid(c, k)) {328 unsigned int j;329 330 for (j = 0; j < KEY_PTRS(k); j++)331 if (ptr_available(c, k, j))332 atomic_inc(&PTR_BUCKET(c, k, j)->pin);333 334 bch_initial_mark_key(c, 0, k);335 }336 }337}338 339static bool is_discard_enabled(struct cache_set *s)340{341 struct cache *ca = s->cache;342 343 if (ca->discard)344 return true;345 346 return false;347}348 349int bch_journal_replay(struct cache_set *s, struct list_head *list)350{351 int ret = 0, keys = 0, entries = 0;352 struct bkey *k;353 struct journal_replay *i =354 list_entry(list->prev, struct journal_replay, list);355 356 uint64_t start = i->j.last_seq, end = i->j.seq, n = start;357 struct keylist keylist;358 359 list_for_each_entry(i, list, list) {360 BUG_ON(i->pin && atomic_read(i->pin) != 1);361 362 if (n != i->j.seq) {363 if (n == start && is_discard_enabled(s))364 pr_info("journal entries %llu-%llu may be discarded! (replaying %llu-%llu)\n",365 n, i->j.seq - 1, start, end);366 else {367 pr_err("journal entries %llu-%llu missing! (replaying %llu-%llu)\n",368 n, i->j.seq - 1, start, end);369 ret = -EIO;370 goto err;371 }372 }373 374 for (k = i->j.start;375 k < bset_bkey_last(&i->j);376 k = bkey_next(k)) {377 trace_bcache_journal_replay_key(k);378 379 bch_keylist_init_single(&keylist, k);380 381 ret = bch_btree_insert(s, &keylist, i->pin, NULL);382 if (ret)383 goto err;384 385 BUG_ON(!bch_keylist_empty(&keylist));386 keys++;387 388 cond_resched();389 }390 391 if (i->pin)392 atomic_dec(i->pin);393 n = i->j.seq + 1;394 entries++;395 }396 397 pr_info("journal replay done, %i keys in %i entries, seq %llu\n",398 keys, entries, end);399err:400 while (!list_empty(list)) {401 i = list_first_entry(list, struct journal_replay, list);402 list_del(&i->list);403 kfree(i);404 }405 406 return ret;407}408 409void bch_journal_space_reserve(struct journal *j)410{411 j->do_reserve = true;412}413 414/* Journalling */415 416static void btree_flush_write(struct cache_set *c)417{418 struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR];419 unsigned int i, nr;420 int ref_nr;421 atomic_t *fifo_front_p, *now_fifo_front_p;422 size_t mask;423 424 if (c->journal.btree_flushing)425 return;426 427 spin_lock(&c->journal.flush_write_lock);428 if (c->journal.btree_flushing) {429 spin_unlock(&c->journal.flush_write_lock);430 return;431 }432 c->journal.btree_flushing = true;433 spin_unlock(&c->journal.flush_write_lock);434 435 /* get the oldest journal entry and check its refcount */436 spin_lock(&c->journal.lock);437 fifo_front_p = &fifo_front(&c->journal.pin);438 ref_nr = atomic_read(fifo_front_p);439 if (ref_nr <= 0) {440 /*441 * do nothing if no btree node references442 * the oldest journal entry443 */444 spin_unlock(&c->journal.lock);445 goto out;446 }447 spin_unlock(&c->journal.lock);448 449 mask = c->journal.pin.mask;450 nr = 0;451 atomic_long_inc(&c->flush_write);452 memset(btree_nodes, 0, sizeof(btree_nodes));453 454 mutex_lock(&c->bucket_lock);455 list_for_each_entry_safe_reverse(b, t, &c->btree_cache, list) {456 /*457 * It is safe to get now_fifo_front_p without holding458 * c->journal.lock here, because we don't need to know459 * the exactly accurate value, just check whether the460 * front pointer of c->journal.pin is changed.461 */462 now_fifo_front_p = &fifo_front(&c->journal.pin);463 /*464 * If the oldest journal entry is reclaimed and front465 * pointer of c->journal.pin changes, it is unnecessary466 * to scan c->btree_cache anymore, just quit the loop and467 * flush out what we have already.468 */469 if (now_fifo_front_p != fifo_front_p)470 break;471 /*472 * quit this loop if all matching btree nodes are473 * scanned and record in btree_nodes[] already.474 */475 ref_nr = atomic_read(fifo_front_p);476 if (nr >= ref_nr)477 break;478 479 if (btree_node_journal_flush(b))480 pr_err("BUG: flush_write bit should not be set here!\n");481 482 mutex_lock(&b->write_lock);483 484 if (!btree_node_dirty(b)) {485 mutex_unlock(&b->write_lock);486 continue;487 }488 489 if (!btree_current_write(b)->journal) {490 mutex_unlock(&b->write_lock);491 continue;492 }493 494 /*495 * Only select the btree node which exactly references496 * the oldest journal entry.497 *498 * If the journal entry pointed by fifo_front_p is499 * reclaimed in parallel, don't worry:500 * - the list_for_each_xxx loop will quit when checking501 * next now_fifo_front_p.502 * - If there are matched nodes recorded in btree_nodes[],503 * they are clean now (this is why and how the oldest504 * journal entry can be reclaimed). These selected nodes505 * will be ignored and skipped in the following for-loop.506 */507 if (((btree_current_write(b)->journal - fifo_front_p) &508 mask) != 0) {509 mutex_unlock(&b->write_lock);510 continue;511 }512 513 set_btree_node_journal_flush(b);514 515 mutex_unlock(&b->write_lock);516 517 btree_nodes[nr++] = b;518 /*519 * To avoid holding c->bucket_lock too long time,520 * only scan for BTREE_FLUSH_NR matched btree nodes521 * at most. If there are more btree nodes reference522 * the oldest journal entry, try to flush them next523 * time when btree_flush_write() is called.524 */525 if (nr == BTREE_FLUSH_NR)526 break;527 }528 mutex_unlock(&c->bucket_lock);529 530 for (i = 0; i < nr; i++) {531 b = btree_nodes[i];532 if (!b) {533 pr_err("BUG: btree_nodes[%d] is NULL\n", i);534 continue;535 }536 537 /* safe to check without holding b->write_lock */538 if (!btree_node_journal_flush(b)) {539 pr_err("BUG: bnode %p: journal_flush bit cleaned\n", b);540 continue;541 }542 543 mutex_lock(&b->write_lock);544 if (!btree_current_write(b)->journal) {545 clear_bit(BTREE_NODE_journal_flush, &b->flags);546 mutex_unlock(&b->write_lock);547 pr_debug("bnode %p: written by others\n", b);548 continue;549 }550 551 if (!btree_node_dirty(b)) {552 clear_bit(BTREE_NODE_journal_flush, &b->flags);553 mutex_unlock(&b->write_lock);554 pr_debug("bnode %p: dirty bit cleaned by others\n", b);555 continue;556 }557 558 __bch_btree_node_write(b, NULL);559 clear_bit(BTREE_NODE_journal_flush, &b->flags);560 mutex_unlock(&b->write_lock);561 }562 563out:564 spin_lock(&c->journal.flush_write_lock);565 c->journal.btree_flushing = false;566 spin_unlock(&c->journal.flush_write_lock);567}568 569#define last_seq(j) ((j)->seq - fifo_used(&(j)->pin) + 1)570 571static void journal_discard_endio(struct bio *bio)572{573 struct journal_device *ja =574 container_of(bio, struct journal_device, discard_bio);575 struct cache *ca = container_of(ja, struct cache, journal);576 577 atomic_set(&ja->discard_in_flight, DISCARD_DONE);578 579 closure_wake_up(&ca->set->journal.wait);580 closure_put(&ca->set->cl);581}582 583static void journal_discard_work(struct work_struct *work)584{585 struct journal_device *ja =586 container_of(work, struct journal_device, discard_work);587 588 submit_bio(&ja->discard_bio);589}590 591static void do_journal_discard(struct cache *ca)592{593 struct journal_device *ja = &ca->journal;594 struct bio *bio = &ja->discard_bio;595 596 if (!ca->discard) {597 ja->discard_idx = ja->last_idx;598 return;599 }600 601 switch (atomic_read(&ja->discard_in_flight)) {602 case DISCARD_IN_FLIGHT:603 return;604 605 case DISCARD_DONE:606 ja->discard_idx = (ja->discard_idx + 1) %607 ca->sb.njournal_buckets;608 609 atomic_set(&ja->discard_in_flight, DISCARD_READY);610 fallthrough;611 612 case DISCARD_READY:613 if (ja->discard_idx == ja->last_idx)614 return;615 616 atomic_set(&ja->discard_in_flight, DISCARD_IN_FLIGHT);617 618 bio_init(bio, ca->bdev, bio->bi_inline_vecs, 1, REQ_OP_DISCARD);619 bio->bi_iter.bi_sector = bucket_to_sector(ca->set,620 ca->sb.d[ja->discard_idx]);621 bio->bi_iter.bi_size = bucket_bytes(ca);622 bio->bi_end_io = journal_discard_endio;623 624 closure_get(&ca->set->cl);625 INIT_WORK(&ja->discard_work, journal_discard_work);626 queue_work(bch_journal_wq, &ja->discard_work);627 }628}629 630static unsigned int free_journal_buckets(struct cache_set *c)631{632 struct journal *j = &c->journal;633 struct cache *ca = c->cache;634 struct journal_device *ja = &c->cache->journal;635 unsigned int n;636 637 /* In case njournal_buckets is not power of 2 */638 if (ja->cur_idx >= ja->discard_idx)639 n = ca->sb.njournal_buckets + ja->discard_idx - ja->cur_idx;640 else641 n = ja->discard_idx - ja->cur_idx;642 643 if (n > (1 + j->do_reserve))644 return n - (1 + j->do_reserve);645 646 return 0;647}648 649static void journal_reclaim(struct cache_set *c)650{651 struct bkey *k = &c->journal.key;652 struct cache *ca = c->cache;653 uint64_t last_seq;654 struct journal_device *ja = &ca->journal;655 atomic_t p __maybe_unused;656 657 atomic_long_inc(&c->reclaim);658 659 while (!atomic_read(&fifo_front(&c->journal.pin)))660 fifo_pop(&c->journal.pin, p);661 662 last_seq = last_seq(&c->journal);663 664 /* Update last_idx */665 666 while (ja->last_idx != ja->cur_idx &&667 ja->seq[ja->last_idx] < last_seq)668 ja->last_idx = (ja->last_idx + 1) %669 ca->sb.njournal_buckets;670 671 do_journal_discard(ca);672 673 if (c->journal.blocks_free)674 goto out;675 676 if (!free_journal_buckets(c))677 goto out;678 679 ja->cur_idx = (ja->cur_idx + 1) % ca->sb.njournal_buckets;680 k->ptr[0] = MAKE_PTR(0,681 bucket_to_sector(c, ca->sb.d[ja->cur_idx]),682 ca->sb.nr_this_dev);683 atomic_long_inc(&c->reclaimed_journal_buckets);684 685 bkey_init(k);686 SET_KEY_PTRS(k, 1);687 c->journal.blocks_free = ca->sb.bucket_size >> c->block_bits;688 689out:690 if (!journal_full(&c->journal))691 __closure_wake_up(&c->journal.wait);692}693 694void bch_journal_next(struct journal *j)695{696 atomic_t p = { 1 };697 698 j->cur = (j->cur == j->w)699 ? &j->w[1]700 : &j->w[0];701 702 /*703 * The fifo_push() needs to happen at the same time as j->seq is704 * incremented for last_seq() to be calculated correctly705 */706 BUG_ON(!fifo_push(&j->pin, p));707 atomic_set(&fifo_back(&j->pin), 1);708 709 j->cur->data->seq = ++j->seq;710 j->cur->dirty = false;711 j->cur->need_write = false;712 j->cur->data->keys = 0;713 714 if (fifo_full(&j->pin))715 pr_debug("journal_pin full (%zu)\n", fifo_used(&j->pin));716}717 718static void journal_write_endio(struct bio *bio)719{720 struct journal_write *w = bio->bi_private;721 722 cache_set_err_on(bio->bi_status, w->c, "journal io error");723 closure_put(&w->c->journal.io);724}725 726static CLOSURE_CALLBACK(journal_write);727 728static CLOSURE_CALLBACK(journal_write_done)729{730 closure_type(j, struct journal, io);731 struct journal_write *w = (j->cur == j->w)732 ? &j->w[1]733 : &j->w[0];734 735 __closure_wake_up(&w->wait);736 continue_at_nobarrier(cl, journal_write, bch_journal_wq);737}738 739static CLOSURE_CALLBACK(journal_write_unlock)740 __releases(&c->journal.lock)741{742 closure_type(c, struct cache_set, journal.io);743 744 c->journal.io_in_flight = 0;745 spin_unlock(&c->journal.lock);746}747 748static CLOSURE_CALLBACK(journal_write_unlocked)749 __releases(c->journal.lock)750{751 closure_type(c, struct cache_set, journal.io);752 struct cache *ca = c->cache;753 struct journal_write *w = c->journal.cur;754 struct bkey *k = &c->journal.key;755 unsigned int i, sectors = set_blocks(w->data, block_bytes(ca)) *756 ca->sb.block_size;757 758 struct bio *bio;759 struct bio_list list;760 761 bio_list_init(&list);762 763 if (!w->need_write) {764 closure_return_with_destructor(cl, journal_write_unlock);765 return;766 } else if (journal_full(&c->journal)) {767 journal_reclaim(c);768 spin_unlock(&c->journal.lock);769 770 btree_flush_write(c);771 continue_at(cl, journal_write, bch_journal_wq);772 return;773 }774 775 c->journal.blocks_free -= set_blocks(w->data, block_bytes(ca));776 777 w->data->btree_level = c->root->level;778 779 bkey_copy(&w->data->btree_root, &c->root->key);780 bkey_copy(&w->data->uuid_bucket, &c->uuid_bucket);781 782 w->data->prio_bucket[ca->sb.nr_this_dev] = ca->prio_buckets[0];783 w->data->magic = jset_magic(&ca->sb);784 w->data->version = BCACHE_JSET_VERSION;785 w->data->last_seq = last_seq(&c->journal);786 w->data->csum = csum_set(w->data);787 788 for (i = 0; i < KEY_PTRS(k); i++) {789 ca = c->cache;790 bio = &ca->journal.bio;791 792 atomic_long_add(sectors, &ca->meta_sectors_written);793 794 bio_reset(bio, ca->bdev, REQ_OP_WRITE | 795 REQ_SYNC | REQ_META | REQ_PREFLUSH | REQ_FUA);796 bio->bi_iter.bi_sector = PTR_OFFSET(k, i);797 bio->bi_iter.bi_size = sectors << 9;798 799 bio->bi_end_io = journal_write_endio;800 bio->bi_private = w;801 bch_bio_map(bio, w->data);802 803 trace_bcache_journal_write(bio, w->data->keys);804 bio_list_add(&list, bio);805 806 SET_PTR_OFFSET(k, i, PTR_OFFSET(k, i) + sectors);807 808 ca->journal.seq[ca->journal.cur_idx] = w->data->seq;809 }810 811 /* If KEY_PTRS(k) == 0, this jset gets lost in air */812 BUG_ON(i == 0);813 814 atomic_dec_bug(&fifo_back(&c->journal.pin));815 bch_journal_next(&c->journal);816 journal_reclaim(c);817 818 spin_unlock(&c->journal.lock);819 820 while ((bio = bio_list_pop(&list)))821 closure_bio_submit(c, bio, cl);822 823 continue_at(cl, journal_write_done, NULL);824}825 826static CLOSURE_CALLBACK(journal_write)827{828 closure_type(c, struct cache_set, journal.io);829 830 spin_lock(&c->journal.lock);831 journal_write_unlocked(&cl->work);832}833 834static void journal_try_write(struct cache_set *c)835 __releases(c->journal.lock)836{837 struct closure *cl = &c->journal.io;838 struct journal_write *w = c->journal.cur;839 840 w->need_write = true;841 842 if (!c->journal.io_in_flight) {843 c->journal.io_in_flight = 1;844 closure_call(cl, journal_write_unlocked, NULL, &c->cl);845 } else {846 spin_unlock(&c->journal.lock);847 }848}849 850static struct journal_write *journal_wait_for_write(struct cache_set *c,851 unsigned int nkeys)852 __acquires(&c->journal.lock)853{854 size_t sectors;855 struct closure cl;856 bool wait = false;857 struct cache *ca = c->cache;858 859 closure_init_stack(&cl);860 861 spin_lock(&c->journal.lock);862 863 while (1) {864 struct journal_write *w = c->journal.cur;865 866 sectors = __set_blocks(w->data, w->data->keys + nkeys,867 block_bytes(ca)) * ca->sb.block_size;868 869 if (sectors <= min_t(size_t,870 c->journal.blocks_free * ca->sb.block_size,871 PAGE_SECTORS << JSET_BITS))872 return w;873 874 if (wait)875 closure_wait(&c->journal.wait, &cl);876 877 if (!journal_full(&c->journal)) {878 if (wait)879 trace_bcache_journal_entry_full(c);880 881 /*882 * XXX: If we were inserting so many keys that they883 * won't fit in an _empty_ journal write, we'll884 * deadlock. For now, handle this in885 * bch_keylist_realloc() - but something to think about.886 */887 BUG_ON(!w->data->keys);888 889 journal_try_write(c); /* unlocks */890 } else {891 if (wait)892 trace_bcache_journal_full(c);893 894 journal_reclaim(c);895 spin_unlock(&c->journal.lock);896 897 btree_flush_write(c);898 }899 900 closure_sync(&cl);901 spin_lock(&c->journal.lock);902 wait = true;903 }904}905 906static void journal_write_work(struct work_struct *work)907{908 struct cache_set *c = container_of(to_delayed_work(work),909 struct cache_set,910 journal.work);911 spin_lock(&c->journal.lock);912 if (c->journal.cur->dirty)913 journal_try_write(c);914 else915 spin_unlock(&c->journal.lock);916}917 918/*919 * Entry point to the journalling code - bio_insert() and btree_invalidate()920 * pass bch_journal() a list of keys to be journalled, and then921 * bch_journal() hands those same keys off to btree_insert_async()922 */923 924atomic_t *bch_journal(struct cache_set *c,925 struct keylist *keys,926 struct closure *parent)927{928 struct journal_write *w;929 atomic_t *ret;930 931 /* No journaling if CACHE_SET_IO_DISABLE set already */932 if (unlikely(test_bit(CACHE_SET_IO_DISABLE, &c->flags)))933 return NULL;934 935 if (!CACHE_SYNC(&c->cache->sb))936 return NULL;937 938 w = journal_wait_for_write(c, bch_keylist_nkeys(keys));939 940 memcpy(bset_bkey_last(w->data), keys->keys, bch_keylist_bytes(keys));941 w->data->keys += bch_keylist_nkeys(keys);942 943 ret = &fifo_back(&c->journal.pin);944 atomic_inc(ret);945 946 if (parent) {947 closure_wait(&w->wait, parent);948 journal_try_write(c);949 } else if (!w->dirty) {950 w->dirty = true;951 queue_delayed_work(bch_flush_wq, &c->journal.work,952 msecs_to_jiffies(c->journal_delay_ms));953 spin_unlock(&c->journal.lock);954 } else {955 spin_unlock(&c->journal.lock);956 }957 958 959 return ret;960}961 962void bch_journal_meta(struct cache_set *c, struct closure *cl)963{964 struct keylist keys;965 atomic_t *ref;966 967 bch_keylist_init(&keys);968 969 ref = bch_journal(c, &keys, cl);970 if (ref)971 atomic_dec_bug(ref);972}973 974void bch_journal_free(struct cache_set *c)975{976 free_pages((unsigned long) c->journal.w[1].data, JSET_BITS);977 free_pages((unsigned long) c->journal.w[0].data, JSET_BITS);978 free_fifo(&c->journal.pin);979}980 981int bch_journal_alloc(struct cache_set *c)982{983 struct journal *j = &c->journal;984 985 spin_lock_init(&j->lock);986 spin_lock_init(&j->flush_write_lock);987 INIT_DELAYED_WORK(&j->work, journal_write_work);988 989 c->journal_delay_ms = 100;990 991 j->w[0].c = c;992 j->w[1].c = c;993 994 if (!(init_fifo(&j->pin, JOURNAL_PIN, GFP_KERNEL)) ||995 !(j->w[0].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)) ||996 !(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)))997 return -ENOMEM;998 999 return 0;1000}1001