--- /dev/null
+/*
+ * 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, int error)
+{
+ struct closure *cl = bio->bi_private;
+ closure_put(cl);
+}
+
+static int journal_read_bucket(struct cache *ca, struct list_head *list,
+ unsigned 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 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", bucket_index);
+
+ while (offset < ca->sb.bucket_size) {
+reread: left = ca->sb.bucket_size - offset;
+ len = min_t(unsigned, left, PAGE_SECTORS << JSET_BITS);
+
+ bio_reset(bio);
+ bio->bi_iter.bi_sector = bucket + offset;
+ bio->bi_bdev = ca->bdev;
+ bio->bi_rw = READ;
+ 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(bio, &cl, ca);
+ 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", bucket_index);
+ return ret;
+ }
+
+ if (bytes > left << 9 ||
+ bytes > PAGE_SIZE << JSET_BITS) {
+ pr_info("%u: too big, %zu bytes, offset %u",
+ 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",
+ bucket_index, bytes, offset);
+ return ret;
+ }
+
+ blocks = set_blocks(j, block_bytes(ca->set));
+
+ 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);
+ }
+
+ list_for_each_entry_reverse(i, list, list) {
+ if (j->seq == i->j.seq)
+ goto next_set;
+
+ if (j->seq < i->j.last_seq)
+ goto next_set;
+
+ 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;
+ memcpy(&i->j, j, bytes);
+ list_add(&i->list, where);
+ ret = 1;
+
+ 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) \
+ ({ \
+ int ret = journal_read_bucket(ca, list, b); \
+ __set_bit(b, bitmap); \
+ if (ret < 0) \
+ return ret; \
+ ret; \
+ })
+
+ struct cache *ca;
+ unsigned iter;
+
+ for_each_cache(ca, c, iter) {
+ struct journal_device *ja = &ca->journal;
+ unsigned long bitmap[SB_JOURNAL_BUCKETS / BITS_PER_LONG];
+ unsigned i, l, r, m;
+ uint64_t seq;
+
+ bitmap_zero(bitmap, SB_JOURNAL_BUCKETS);
+ pr_debug("%u journal buckets", 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++) {
+ 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");
+
+ for (l = find_first_zero_bit(bitmap, ca->sb.njournal_buckets);
+ l < ca->sb.njournal_buckets;
+ l = find_next_zero_bit(bitmap, ca->sb.njournal_buckets, l + 1))
+ if (read_bucket(l))
+ goto bsearch;
+
+ /* no journal entries on this device? */
+ if (l == ca->sb.njournal_buckets)
+ continue;
+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", 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",
+ 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;
+
+ }
+ }
+
+ 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 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);
+ }
+ }
+}
+
+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);
+
+ cache_set_err_on(n != i->j.seq, s,
+"bcache: journal entries %llu-%llu missing! (replaying %llu-%llu)",
+ n, i->j.seq - 1, start, end);
+
+ 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",
+ 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;
+}
+
+/* Journalling */
+
+static void btree_flush_write(struct cache_set *c)
+{
+ /*
+ * Try to find the btree node with that references the oldest journal
+ * entry, best is our current candidate and is locked if non NULL:
+ */
+ struct btree *b, *best;
+ unsigned i;
+retry:
+ best = NULL;
+
+ for_each_cached_btree(b, c, i)
+ if (btree_current_write(b)->journal) {
+ if (!best)
+ best = b;
+ else if (journal_pin_cmp(c,
+ btree_current_write(best)->journal,
+ btree_current_write(b)->journal)) {
+ best = b;
+ }
+ }
+
+ b = best;
+ if (b) {
+ mutex_lock(&b->write_lock);
+ if (!btree_current_write(b)->journal) {
+ mutex_unlock(&b->write_lock);
+ /* We raced */
+ goto retry;
+ }
+
+ __bch_btree_node_write(b, NULL);
+ mutex_unlock(&b->write_lock);
+ }
+}
+
+#define last_seq(j) ((j)->seq - fifo_used(&(j)->pin) + 1)
+
+static void journal_discard_endio(struct bio *bio, int error)
+{
+ 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(0, &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);
+ bio->bi_iter.bi_sector = bucket_to_sector(ca->set,
+ ca->sb.d[ja->discard_idx]);
+ bio->bi_bdev = ca->bdev;
+ bio->bi_rw = REQ_WRITE|REQ_DISCARD;
+ bio->bi_max_vecs = 1;
+ bio->bi_io_vec = bio->bi_inline_vecs;
+ 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);
+ schedule_work(&ja->discard_work);
+ }
+}
+
+static void journal_reclaim(struct cache_set *c)
+{
+ struct bkey *k = &c->journal.key;
+ struct cache *ca;
+ uint64_t last_seq;
+ unsigned iter, n = 0;
+ atomic_t p;
+
+ while (!atomic_read(&fifo_front(&c->journal.pin)))
+ fifo_pop(&c->journal.pin, p);
+
+ last_seq = last_seq(&c->journal);
+
+ /* Update last_idx */
+
+ for_each_cache(ca, c, iter) {
+ struct journal_device *ja = &ca->journal;
+
+ 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;
+ }
+
+ for_each_cache(ca, c, iter)
+ do_journal_discard(ca);
+
+ if (c->journal.blocks_free)
+ goto out;
+
+ /*
+ * Allocate:
+ * XXX: Sort by free journal space
+ */
+
+ for_each_cache(ca, c, iter) {
+ struct journal_device *ja = &ca->journal;
+ unsigned next = (ja->cur_idx + 1) % ca->sb.njournal_buckets;
+
+ /* No space available on this device */
+ if (next == ja->discard_idx)
+ continue;
+
+ ja->cur_idx = next;
+ k->ptr[n++] = PTR(0,
+ bucket_to_sector(c, ca->sb.d[ja->cur_idx]),
+ ca->sb.nr_this_dev);
+ }
+
+ bkey_init(k);
+ SET_KEY_PTRS(k, n);
+
+ if (n)
+ c->journal.blocks_free = c->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)", fifo_used(&j->pin));
+}
+
+static void journal_write_endio(struct bio *bio, int error)
+{
+ struct journal_write *w = bio->bi_private;
+
+ cache_set_err_on(error, w->c, "journal io error");
+ closure_put(&w->c->journal.io);
+}
+
+static void journal_write(struct closure *);
+
+static void journal_write_done(struct closure *cl)
+{
+ struct journal *j = container_of(cl, 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, system_wq);
+}
+
+static void journal_write_unlock(struct closure *cl)
+{
+ struct cache_set *c = container_of(cl, struct cache_set, journal.io);
+
+ c->journal.io_in_flight = 0;
+ spin_unlock(&c->journal.lock);
+}
+
+static void journal_write_unlocked(struct closure *cl)
+ __releases(c->journal.lock)
+{
+ struct cache_set *c = container_of(cl, struct cache_set, journal.io);
+ struct cache *ca;
+ struct journal_write *w = c->journal.cur;
+ struct bkey *k = &c->journal.key;
+ unsigned i, sectors = set_blocks(w->data, block_bytes(c)) *
+ c->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);
+ } else if (journal_full(&c->journal)) {
+ journal_reclaim(c);
+ spin_unlock(&c->journal.lock);
+
+ btree_flush_write(c);
+ continue_at(cl, journal_write, system_wq);
+ }
+
+ c->journal.blocks_free -= set_blocks(w->data, block_bytes(c));
+
+ 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);
+
+ for_each_cache(ca, c, i)
+ w->data->prio_bucket[ca->sb.nr_this_dev] = ca->prio_buckets[0];
+
+ w->data->magic = jset_magic(&c->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 = PTR_CACHE(c, k, i);
+ bio = &ca->journal.bio;
+
+ atomic_long_add(sectors, &ca->meta_sectors_written);
+
+ bio_reset(bio);
+ bio->bi_iter.bi_sector = PTR_OFFSET(k, i);
+ bio->bi_bdev = ca->bdev;
+ bio->bi_rw = REQ_WRITE|REQ_SYNC|REQ_META|REQ_FLUSH|REQ_FUA;
+ 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);
+ 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;
+ }
+
+ 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(bio, cl, c->cache[0]);
+
+ continue_at(cl, journal_write_done, NULL);
+}
+
+static void journal_write(struct closure *cl)
+{
+ struct cache_set *c = container_of(cl, struct cache_set, journal.io);
+
+ spin_lock(&c->journal.lock);
+ journal_write_unlocked(cl);
+}
+
+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 nkeys)
+{
+ size_t sectors;
+ struct closure cl;
+ bool wait = false;
+
+ 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(c)) * c->sb.block_size;
+
+ if (sectors <= min_t(size_t,
+ c->journal.blocks_free * c->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;
+
+ if (!CACHE_SYNC(&c->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;
+ schedule_delayed_work(&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);
+ 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, JSET_BITS)) ||
+ !(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL, JSET_BITS)))
+ return -ENOMEM;
+
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff