// SPDX-License-Identifier: GPL-2.0
/*
* bcache journalling code, for btree insertions
*
* Copyright 2012 Google, Inc.
*/
#include "bcache.h"
#include "btree.h"
#include "debug.h"
#include "extents.h"
#include <trace/events/bcache.h>
/*
* Journal replay/recovery:
*
* This code is all driven from run_cache_set(); we first read the journal
* entries, do some other stuff, then we mark all the keys in the journal
* entries (same as garbage collection would), then we replay them - reinserting
* them into the cache in precisely the same order as they appear in the
* journal.
*
* We only journal keys that go in leaf nodes, which simplifies things quite a
* bit.
*/
static void journal_read_endio(struct bio *bio)
{
struct closure *cl = bio->bi_private;
closure_put(cl);
}
static int journal_read_bucket(struct cache *ca, struct list_head *list,
unsigned int bucket_index)
{
struct journal_device *ja = &ca->journal;
struct bio *bio = &ja->bio;
struct journal_replay *i;
struct jset *j, *data = ca->set->journal.w[0].data;
struct closure cl;
unsigned int len, left, offset = 0;
int ret = 0;
sector_t bucket = bucket_to_sector(ca->set, ca->sb.d[bucket_index]);
closure_init_stack(&cl);
pr_debug("reading %u\n", bucket_index);
while (offset < ca->sb.bucket_size) {
reread: left = ca->sb.bucket_size - offset;
len = min_t(unsigned int, left, PAGE_SECTORS << JSET_BITS);
bio_reset(bio, ca->bdev, REQ_OP_READ);
bio->bi_iter.bi_sector = bucket + offset;
bio->bi_iter.bi_size = len << 9;
bio->bi_end_io = journal_read_endio;
bio->bi_private = &cl;
bch_bio_map(bio, data);
closure_bio_submit(ca->set, bio, &cl);
closure_sync(&cl);
/* This function could be simpler now since we no longer write
* journal entries that overlap bucket boundaries; this means
* the start of a bucket will always have a valid journal entry
* if it has any journal entries at all.
*/
j = data;
while (len) {
struct list_head *where;
size_t blocks, bytes = set_bytes(j);
if (j->magic != jset_magic(&ca->sb)) {
pr_debug("%u: bad magic\n", bucket_index);
return ret;
}
if (bytes > left << 9 ||
bytes > PAGE_SIZE << JSET_BITS) {
pr_info("%u: too big, %zu bytes, offset %u\n",
bucket_index, bytes, offset);
return ret;
}
if (bytes > len << 9)
goto reread;
if (j->csum != csum_set(j)) {
pr_info("%u: bad csum, %zu bytes, offset %u\n",
bucket_index, bytes, offset);
return ret;
}
blocks = set_blocks(j, block_bytes(ca));
/*
* Nodes in 'list' are in linear increasing order of
* i->j.seq, the node on head has the smallest (oldest)
* journal seq, the node on tail has the biggest
* (latest) journal seq.
*/
/*
* Check from the oldest jset for last_seq. If
* i->j.seq < j->last_seq, it means the oldest jset
* in list is expired and useless, remove it from
* this list. Otherwise, j is a candidate jset for
* further following checks.
*/
while (!list_empty(list)) {
i = list_first_entry(list,
struct journal_replay, list);
if (i->j.seq >= j->last_seq)
break;
list_del(&i->list);
kfree(i);
}
/* iterate list in reverse order (from latest jset) */
list_for_each_entry_reverse(i, list, list) {
if (j->seq == i->j.seq)
goto next_set;
/*
* if j->seq is less than any i->j.last_seq
* in list, j is an expired and useless jset.
*/
if (j->seq < i->j.last_seq)
goto next_set;
/*
* 'where' points to first jset in list which
* is elder then j.
*/
if (j->seq > i->j.seq) {
where = &i->list;
goto add;
}
}
where = list;
add:
i = kmalloc(offsetof(struct journal_replay, j) +
bytes, GFP_KERNEL);
if (!i)
return -ENOMEM;
unsafe_memcpy(&i->j, j, bytes,
/* "bytes" was calculated by set_bytes() above */);
/* Add to the location after 'where' points to */
list_add(&i->list, where);
ret = 1;
if (j->seq > ja->seq[bucket_index])
ja->seq[bucket_index] = j->seq;
next_set:
offset += blocks * ca->sb.block_size;
len -= blocks * ca->sb.block_size;
j = ((void *) j) + blocks * block_bytes(ca);
}
}
return ret;
}
int bch_journal_read(struct cache_set *c, struct list_head *list)
{
#define read_bucket(b) \
({ \
ret = journal_read_bucket(ca, list, b); \
__set_bit(b, bitmap); \
if (ret < 0) \
return ret; \
ret; \
})
struct cache *ca = c->cache;
int ret = 0;
struct journal_device *ja = &ca->journal;
DECLARE_BITMAP(bitmap, SB_JOURNAL_BUCKETS);
unsigned int i, l, r, m;
uint64_t seq;
bitmap_zero(bitmap, SB_JOURNAL_BUCKETS);
pr_debug("%u journal buckets\n", ca->sb.njournal_buckets);
/*
* Read journal buckets ordered by golden ratio hash to quickly
* find a sequence of buckets with valid journal entries
*/
for (i = 0; i < ca->sb.njournal_buckets; i++) {
/*
* We must try the index l with ZERO first for
* correctness due to the scenario that the journal
* bucket is circular buffer which might have wrapped
*/
l = (i * 2654435769U) % ca->sb.njournal_buckets;
if (test_bit(l, bitmap))
break;
if (read_bucket(l))
goto bsearch;
}
/*
* If that fails, check all the buckets we haven't checked
* already
*/
pr_debug("falling back to linear search\n");
for_each_clear_bit(l, bitmap, ca->sb.njournal_buckets)
if (read_bucket(l))
goto bsearch;
/* no journal entries on this device? */
if (l == ca->sb.njournal_buckets)
goto out;
bsearch:
BUG_ON(list_empty(list));
/* Binary search */
m = l;
r = find_next_bit(bitmap, ca->sb.njournal_buckets, l + 1);
pr_debug("starting binary search, l %u r %u\n", l, r);
while (l + 1 < r) {
seq = list_entry(list->prev, struct journal_replay,
list)->j.seq;
m = (l + r) >> 1;
read_bucket(m);
if (seq != list_entry(list->prev, struct journal_replay,
list)->j.seq)
l = m;
else
r = m;
}
/*
* Read buckets in reverse order until we stop finding more
* journal entries
*/
pr_debug("finishing up: m %u njournal_buckets %u\n",
m, ca->sb.njournal_buckets);
l = m;
while (1) {
if (!l--)
l = ca->sb.njournal_buckets - 1;
if (l == m)
break;
if (test_bit(l, bitmap))
continue;
if (!read_bucket(l))
break;
}
seq = 0;
for (i = 0; i < ca->sb.njournal_buckets; i++)
if (ja->seq[i] > seq) {
seq = ja->seq[i];
/*
* When journal_reclaim() goes to allocate for
* the first time, it'll use the bucket after
* ja->cur_idx
*/
ja->cur_idx = i;
ja->last_idx = ja->discard_idx = (i + 1) %
ca->sb.njournal_buckets;
}
out:
if (!list_empty(list))
c->journal.seq = list_entry(list->prev,
struct journal_replay,
list)->j.seq;
return 0;
#undef read_bucket
}
void bch_journal_mark(struct cache_set *c, struct list_head *list)
{
atomic_t p = { 0 };
struct bkey *k;
struct journal_replay *i;
struct journal *j = &c->journal;
uint64_t last = j->seq;
/*
* journal.pin should never fill up - we never write a journal
* entry when it would fill up. But if for some reason it does, we
* iterate over the list in reverse order so that we can just skip that
* refcount instead of bugging.
*/
list_for_each_entry_reverse(i, list, list) {
BUG_ON(last < i->j.seq);
i->pin = NULL;
while (last-- != i->j.seq)
if (fifo_free(&j->pin) > 1) {
fifo_push_front(&j->pin, p);
atomic_set(&fifo_front(&j->pin), 0);
}
if (fifo_free(&j->pin) > 1) {
fifo_push_front(&j->pin, p);
i->pin = &fifo_front(&j->pin);
atomic_set(i->pin, 1);
}
for (k = i->j.start;
k < bset_bkey_last(&i->j);
k = bkey_next(k))
if (!__bch_extent_invalid(c, k)) {
unsigned int j;
for (j = 0; j < KEY_PTRS(k); j++)
if (ptr_available(c, k, j))
atomic_inc(&PTR_BUCKET(c, k, j)->pin);
bch_initial_mark_key(c, 0, k);
}
}
}
static bool is_discard_enabled(struct cache_set *s)
{
struct cache *ca = s->cache;
if (ca->discard)
return true;
return false;
}
int bch_journal_replay(struct cache_set *s, struct list_head *list)
{
int ret = 0, keys = 0, entries = 0;
struct bkey *k;
struct journal_replay *i =
list_entry(list->prev, struct journal_replay, list);
uint64_t start = i->j.last_seq, end = i->j.seq, n = start;
struct keylist keylist;
list_for_each_entry(i, list, list) {
BUG_ON(i->pin && atomic_read(i->pin) != 1);
if (n != i->j.seq) {
if (n == start && is_discard_enabled(s))
pr_info("journal entries %llu-%llu may be discarded! (replaying %llu-%llu)\n",
n, i->j.seq - 1, start, end);
else {
pr_err("journal entries %llu-%llu missing! (replaying %llu-%llu)\n",
n, i->j.seq - 1, start, end);
ret = -EIO;
goto err;
}
}
for (k = i->j.start;
k < bset_bkey_last(&i->j);
k = bkey_next(k)) {
trace_bcache_journal_replay_key(k);
bch_keylist_init_single(&keylist, k);
ret = bch_btree_insert(s, &keylist, i->pin, NULL);
if (ret)
goto err;
BUG_ON(!bch_keylist_empty(&keylist));
keys++;
cond_resched();
}
if (i->pin)
atomic_dec(i->pin);
n = i->j.seq + 1;
entries++;
}
pr_info("journal replay done, %i keys in %i entries, seq %llu\n",
keys, entries, end);
err:
while (!list_empty(list)) {
i = list_first_entry(list, struct journal_replay, list);
list_del(&i->list);
kfree(i);
}
return ret;
}
void bch_journal_space_reserve(struct journal *j)
{
j->do_reserve = true;
}
/* Journalling */
static void btree_flush_write(struct cache_set *c)
{
struct btree *b, *t, *btree_nodes[BTREE_FLUSH_NR];
unsigned int i, nr;
int ref_nr;
atomic_t *fifo_front_p, *now_fifo_front_p;
size_t mask;
if (c->journal.btree_flushing)
return;
spin_lock(&c->journal.flush_write_lock);
if (c->journal.btree_flushing) {
spin_unlock(&c->journal.flush_write_lock);
return;
}
c->journal.btree_flushing = true;
spin_unlock(&c->journal.flush_write_lock);
/* get the oldest journal entry and check its refcount */
spin_lock(&c->journal.lock);
fifo_front_p = &fifo_front(&c->journal.pin);
ref_nr = atomic_read(fifo_front_p);
if (ref_nr <= 0) {
/*
* do nothing if no btree node references
* the oldest journal entry
*/
spin_unlock(&c->journal.lock);
goto out;
}
spin_unlock(&c->journal.lock);
mask = c->journal.pin.mask;
nr = 0;
atomic_long_inc(&c->flush_write);
memset(btree_nodes, 0, sizeof(btree_nodes));
mutex_lock(&c->bucket_lock);
list_for_each_entry_safe_reverse(b, t, &c->btree_cache, list) {
/*
* It is safe to get now_fifo_front_p without holding
* c->journal.lock here, because we don't need to know
* the exactly accurate value, just check whether the
* front pointer of c->journal.pin is changed.
*/
now_fifo_front_p = &fifo_front(&c->journal.pin);
/*
* If the oldest journal entry is reclaimed and front
* pointer of c->journal.pin changes, it is unnecessary
* to scan c->btree_cache anymore, just quit the loop and
* flush out what we have already.
*/
if (now_fifo_front_p != fifo_front_p)
break;
/*
* quit this loop if all matching btree nodes are
* scanned and record in btree_nodes[] already.
*/
ref_nr = atomic_read(fifo_front_p);
if (nr >= ref_nr)
break;
if (btree_node_journal_flush(b))
pr_err("BUG: flush_write bit should not be set here!\n");
mutex_lock(&b->write_lock);
if (!btree_node_dirty(b)) {
mutex_unlock(&b->write_lock);
continue;
}
if (!btree_current_write(b)->journal) {
mutex_unlock(&b->write_lock);
continue;
}
/*
* Only select the btree node which exactly references
* the oldest journal entry.
*
* If the journal entry pointed by fifo_front_p is
* reclaimed in parallel, don't worry:
* - the list_for_each_xxx loop will quit when checking
* next now_fifo_front_p.
* - If there are matched nodes recorded in btree_nodes[],
* they are clean now (this is why and how the oldest
* journal entry can be reclaimed). These selected nodes
* will be ignored and skipped in the following for-loop.
*/
if (((btree_current_write(b)->journal - fifo_front_p) &
mask) != 0) {
mutex_unlock(&b->write_lock);
continue;
}
set_btree_node_journal_flush(b);
mutex_unlock(&b->write_lock);
btree_nodes[nr++] = b;
/*
* To avoid holding c->bucket_lock too long time,
* only scan for BTREE_FLUSH_NR matched btree nodes
* at most. If there are more btree nodes reference
* the oldest journal entry, try to flush them next
* time when btree_flush_write() is called.
*/
if (nr == BTREE_FLUSH_NR)
break;
}
mutex_unlock(&c->bucket_lock);
for (i = 0; i < nr; i++) {
b = btree_nodes[i];
if (!b) {
pr_err("BUG: btree_nodes[%d] is NULL\n", i);
continue;
}
/* safe to check without holding b->write_lock */
if (!btree_node_journal_flush(b)) {
pr_err("BUG: bnode %p: journal_flush bit cleaned\n", b);
continue;
}
mutex_lock(&b->write_lock);
if (!btree_current_write(b)->journal) {
clear_bit(BTREE_NODE_journal_flush, &b->flags);
mutex_unlock(&b->write_lock);
pr_debug("bnode %p: written by others\n", b);
continue;
}
if (!btree_node_dirty(b)) {
clear_bit(BTREE_NODE_journal_flush, &b->flags);
mutex_unlock(&b->write_lock);
pr_debug("bnode %p: dirty bit cleaned by others\n", b);
continue;
}
__bch_btree_node_write(b, NULL);
clear_bit(BTREE_NODE_journal_flush, &b->flags);
mutex_unlock(&b->write_lock);
}
out:
spin_lock(&c->journal.flush_write_lock);
c->journal.btree_flushing = false;
spin_unlock(&c->journal.flush_write_lock);
}
#define last_seq(j) ((j)->seq - fifo_used(&(j)->pin) + 1)
static void journal_discard_endio(struct bio *bio)
{
struct journal_device *ja =
container_of(bio, struct journal_device, discard_bio);
struct cache *ca = container_of(ja, struct cache, journal);
atomic_set(&ja->discard_in_flight, DISCARD_DONE);
closure_wake_up(&ca->set->journal.wait);
closure_put(&ca->set->cl);
}
static void journal_discard_work(struct work_struct *work)
{
struct journal_device *ja =
container_of(work, struct journal_device, discard_work);
submit_bio(&ja->discard_bio);
}
static void do_journal_discard(struct cache *ca)
{
struct journal_device *ja = &ca->journal;
struct bio *bio = &ja->discard_bio;
if (!ca->discard) {
ja->discard_idx = ja->last_idx;
return;
}
switch (atomic_read(&ja->discard_in_flight)) {
case DISCARD_IN_FLIGHT:
return;
case DISCARD_DONE:
ja->discard_idx = (ja->discard_idx + 1) %
ca->sb.njournal_buckets;
atomic_set(&ja->discard_in_flight, DISCARD_READY);
fallthrough;
case DISCARD_READY:
if (ja->discard_idx == ja->last_idx)
return;
atomic_set(&ja->discard_in_flight, DISCARD_IN_FLIGHT);
bio_init(bio, ca->bdev, bio->bi_inline_vecs, 1, REQ_OP_DISCARD);
bio->bi_iter.bi_sector = bucket_to_sector(ca->set,
ca->sb.d[ja->discard_idx]);
bio->bi_iter.bi_size = bucket_bytes(ca);
bio->bi_end_io = journal_discard_endio;
closure_get(&ca->set->cl);
INIT_WORK(&ja->discard_work, journal_discard_work);
queue_work(bch_journal_wq, &ja->discard_work);
}
}
static unsigned int free_journal_buckets(struct cache_set *c)
{
struct journal *j = &c->journal;
struct cache *ca = c->cache;
struct journal_device *ja = &c->cache->journal;
unsigned int n;
/* In case njournal_buckets is not power of 2 */
if (ja->cur_idx >= ja->discard_idx)
n = ca->sb.njournal_buckets + ja->discard_idx - ja->cur_idx;
else
n = ja->discard_idx - ja->cur_idx;
if (n > (1 + j->do_reserve))
return n - (1 + j->do_reserve);
return 0;
}
static void journal_reclaim(struct cache_set *c)
{
struct bkey *k = &c->journal.key;
struct cache *ca = c->cache;
uint64_t last_seq;
struct journal_device *ja = &ca->journal;
atomic_t p __maybe_unused;
atomic_long_inc(&c->reclaim);
while (!atomic_read(&fifo_front(&c->journal.pin)))
fifo_pop(&c->journal.pin, p);
last_seq = last_seq(&c->journal);
/* Update last_idx */
while (ja->last_idx != ja->cur_idx &&
ja->seq[ja->last_idx] < last_seq)
ja->last_idx = (ja->last_idx + 1) %
ca->sb.njournal_buckets;
do_journal_discard(ca);
if (c->journal.blocks_free)
goto out;
if (!free_journal_buckets(c))
goto out;
ja->cur_idx = (ja->cur_idx + 1) % ca->sb.njournal_buckets;
k->ptr[0] = MAKE_PTR(0,
bucket_to_sector(c, ca->sb.d[ja->cur_idx]),
ca->sb.nr_this_dev);
atomic_long_inc(&c->reclaimed_journal_buckets);
bkey_init(k);
SET_KEY_PTRS(k, 1);
c->journal.blocks_free = ca->sb.bucket_size >> c->block_bits;
out:
if (!journal_full(&c->journal))
__closure_wake_up(&c->journal.wait);
}
void bch_journal_next(struct journal *j)
{
atomic_t p = { 1 };
j->cur = (j->cur == j->w)
? &j->w[1]
: &j->w[0];
/*
* The fifo_push() needs to happen at the same time as j->seq is
* incremented for last_seq() to be calculated correctly
*/
BUG_ON(!fifo_push(&j->pin, p));
atomic_set(&fifo_back(&j->pin), 1);
j->cur->data->seq = ++j->seq;
j->cur->dirty = false;
j->cur->need_write = false;
j->cur->data->keys = 0;
if (fifo_full(&j->pin))
pr_debug("journal_pin full (%zu)\n", fifo_used(&j->pin));
}
static void journal_write_endio(struct bio *bio)
{
struct journal_write *w = bio->bi_private;
cache_set_err_on(bio->bi_status, w->c, "journal io error");
closure_put(&w->c->journal.io);
}
static CLOSURE_CALLBACK(journal_write);
static CLOSURE_CALLBACK(journal_write_done)
{
closure_type(j, struct journal, io);
struct journal_write *w = (j->cur == j->w)
? &j->w[1]
: &j->w[0];
__closure_wake_up(&w->wait);
continue_at_nobarrier(cl, journal_write, bch_journal_wq);
}
static CLOSURE_CALLBACK(journal_write_unlock)
__releases(&c->journal.lock)
{
closure_type(c, struct cache_set, journal.io);
c->journal.io_in_flight = 0;
spin_unlock(&c->journal.lock);
}
static CLOSURE_CALLBACK(journal_write_unlocked)
__releases(c->journal.lock)
{
closure_type(c, struct cache_set, journal.io);
struct cache *ca = c->cache;
struct journal_write *w = c->journal.cur;
struct bkey *k = &c->journal.key;
unsigned int i, sectors = set_blocks(w->data, block_bytes(ca)) *
ca->sb.block_size;
struct bio *bio;
struct bio_list list;
bio_list_init(&list);
if (!w->need_write) {
closure_return_with_destructor(cl, journal_write_unlock);
return;
} else if (journal_full(&c->journal)) {
journal_reclaim(c);
spin_unlock(&c->journal.lock);
btree_flush_write(c);
continue_at(cl, journal_write, bch_journal_wq);
return;
}
c->journal.blocks_free -= set_blocks(w->data, block_bytes(ca));
w->data->btree_level = c->root->level;
bkey_copy(&w->data->btree_root, &c->root->key);
bkey_copy(&w->data->uuid_bucket, &c->uuid_bucket);
w->data->prio_bucket[ca->sb.nr_this_dev] = ca->prio_buckets[0];
w->data->magic = jset_magic(&ca->sb);
w->data->version = BCACHE_JSET_VERSION;
w->data->last_seq = last_seq(&c->journal);
w->data->csum = csum_set(w->data);
for (i = 0; i < KEY_PTRS(k); i++) {
ca = c->cache;
bio = &ca->journal.bio;
atomic_long_add(sectors, &ca->meta_sectors_written);
bio_reset(bio, ca->bdev, REQ_OP_WRITE |
REQ_SYNC | REQ_META | REQ_PREFLUSH | REQ_FUA);
bio->bi_iter.bi_sector = PTR_OFFSET(k, i);
bio->bi_iter.bi_size = sectors << 9;
bio->bi_end_io = journal_write_endio;
bio->bi_private = w;
bch_bio_map(bio, w->data);
trace_bcache_journal_write(bio, w->data->keys);
bio_list_add(&list, bio);
SET_PTR_OFFSET(k, i, PTR_OFFSET(k, i) + sectors);
ca->journal.seq[ca->journal.cur_idx] = w->data->seq;
}
/* If KEY_PTRS(k) == 0, this jset gets lost in air */
BUG_ON(i == 0);
atomic_dec_bug(&fifo_back(&c->journal.pin));
bch_journal_next(&c->journal);
journal_reclaim(c);
spin_unlock(&c->journal.lock);
while ((bio = bio_list_pop(&list)))
closure_bio_submit(c, bio, cl);
continue_at(cl, journal_write_done, NULL);
}
static CLOSURE_CALLBACK(journal_write)
{
closure_type(c, struct cache_set, journal.io);
spin_lock(&c->journal.lock);
journal_write_unlocked(&cl->work);
}
static void journal_try_write(struct cache_set *c)
__releases(c->journal.lock)
{
struct closure *cl = &c->journal.io;
struct journal_write *w = c->journal.cur;
w->need_write = true;
if (!c->journal.io_in_flight) {
c->journal.io_in_flight = 1;
closure_call(cl, journal_write_unlocked, NULL, &c->cl);
} else {
spin_unlock(&c->journal.lock);
}
}
static struct journal_write *journal_wait_for_write(struct cache_set *c,
unsigned int nkeys)
__acquires(&c->journal.lock)
{
size_t sectors;
struct closure cl;
bool wait = false;
struct cache *ca = c->cache;
closure_init_stack(&cl);
spin_lock(&c->journal.lock);
while (1) {
struct journal_write *w = c->journal.cur;
sectors = __set_blocks(w->data, w->data->keys + nkeys,
block_bytes(ca)) * ca->sb.block_size;
if (sectors <= min_t(size_t,
c->journal.blocks_free * ca->sb.block_size,
PAGE_SECTORS << JSET_BITS))
return w;
if (wait)
closure_wait(&c->journal.wait, &cl);
if (!journal_full(&c->journal)) {
if (wait)
trace_bcache_journal_entry_full(c);
/*
* XXX: If we were inserting so many keys that they
* won't fit in an _empty_ journal write, we'll
* deadlock. For now, handle this in
* bch_keylist_realloc() - but something to think about.
*/
BUG_ON(!w->data->keys);
journal_try_write(c); /* unlocks */
} else {
if (wait)
trace_bcache_journal_full(c);
journal_reclaim(c);
spin_unlock(&c->journal.lock);
btree_flush_write(c);
}
closure_sync(&cl);
spin_lock(&c->journal.lock);
wait = true;
}
}
static void journal_write_work(struct work_struct *work)
{
struct cache_set *c = container_of(to_delayed_work(work),
struct cache_set,
journal.work);
spin_lock(&c->journal.lock);
if (c->journal.cur->dirty)
journal_try_write(c);
else
spin_unlock(&c->journal.lock);
}
/*
* Entry point to the journalling code - bio_insert() and btree_invalidate()
* pass bch_journal() a list of keys to be journalled, and then
* bch_journal() hands those same keys off to btree_insert_async()
*/
atomic_t *bch_journal(struct cache_set *c,
struct keylist *keys,
struct closure *parent)
{
struct journal_write *w;
atomic_t *ret;
/* No journaling if CACHE_SET_IO_DISABLE set already */
if (unlikely(test_bit(CACHE_SET_IO_DISABLE, &c->flags)))
return NULL;
if (!CACHE_SYNC(&c->cache->sb))
return NULL;
w = journal_wait_for_write(c, bch_keylist_nkeys(keys));
memcpy(bset_bkey_last(w->data), keys->keys, bch_keylist_bytes(keys));
w->data->keys += bch_keylist_nkeys(keys);
ret = &fifo_back(&c->journal.pin);
atomic_inc(ret);
if (parent) {
closure_wait(&w->wait, parent);
journal_try_write(c);
} else if (!w->dirty) {
w->dirty = true;
queue_delayed_work(bch_flush_wq, &c->journal.work,
msecs_to_jiffies(c->journal_delay_ms));
spin_unlock(&c->journal.lock);
} else {
spin_unlock(&c->journal.lock);
}
return ret;
}
void bch_journal_meta(struct cache_set *c, struct closure *cl)
{
struct keylist keys;
atomic_t *ref;
bch_keylist_init(&keys);
ref = bch_journal(c, &keys, cl);
if (ref)
atomic_dec_bug(ref);
}
void bch_journal_free(struct cache_set *c)
{
free_pages((unsigned long) c->journal.w[1].data, JSET_BITS);
free_pages((unsigned long) c->journal.w[0].data, JSET_BITS);
free_fifo(&c->journal.pin);
}
int bch_journal_alloc(struct cache_set *c)
{
struct journal *j = &c->journal;
spin_lock_init(&j->lock);
spin_lock_init(&j->flush_write_lock);
INIT_DELAYED_WORK(&j->work, journal_write_work);
c->journal_delay_ms = 100;
j->w[0].c = c;
j->w[1].c = c;
if (!(init_fifo(&j->pin, JOURNAL_PIN, GFP_KERNEL)) ||
!(j->w[0].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)) ||
!(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL|__GFP_COMP, JSET_BITS)))
return -ENOMEM;
return 0;
}
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