Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 3f4211b..ba434d9 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -35,7 +35,7 @@
#include <linux/rcupdate.h>
#include <linux/sched/clock.h>
#include <linux/rculist.h>
-
+#include <linux/delay.h>
#include <trace/events/bcache.h>
/*
@@ -207,6 +207,11 @@
struct bset *i = btree_bset_first(b);
struct btree_iter *iter;
+ /*
+ * c->fill_iter can allocate an iterator with more memory space
+ * than static MAX_BSETS.
+ * See the comment arount cache_set->fill_iter.
+ */
iter = mempool_alloc(&b->c->fill_iter, GFP_NOIO);
iter->size = b->c->sb.bucket_size / b->c->sb.block_size;
iter->used = 0;
@@ -424,13 +429,14 @@
bset_sector_offset(&b->keys, i));
if (!bch_bio_alloc_pages(b->bio, __GFP_NOWARN|GFP_NOWAIT)) {
- int j;
struct bio_vec *bv;
- void *base = (void *) ((unsigned long) i & ~(PAGE_SIZE - 1));
+ void *addr = (void *) ((unsigned long) i & ~(PAGE_SIZE - 1));
+ struct bvec_iter_all iter_all;
- bio_for_each_segment_all(bv, b->bio, j)
- memcpy(page_address(bv->bv_page),
- base + j * PAGE_SIZE, PAGE_SIZE);
+ bio_for_each_segment_all(bv, b->bio, iter_all) {
+ memcpy(page_address(bv->bv_page), addr, PAGE_SIZE);
+ addr += PAGE_SIZE;
+ }
bch_submit_bbio(b->bio, b->c, &k.key, 0);
@@ -607,6 +613,10 @@
static struct btree *mca_bucket_alloc(struct cache_set *c,
struct bkey *k, gfp_t gfp)
{
+ /*
+ * kzalloc() is necessary here for initialization,
+ * see code comments in bch_btree_keys_init().
+ */
struct btree *b = kzalloc(sizeof(struct btree), gfp);
if (!b)
@@ -649,7 +659,25 @@
up(&b->io_mutex);
}
+retry:
+ /*
+ * BTREE_NODE_dirty might be cleared in btree_flush_btree() by
+ * __bch_btree_node_write(). To avoid an extra flush, acquire
+ * b->write_lock before checking BTREE_NODE_dirty bit.
+ */
mutex_lock(&b->write_lock);
+ /*
+ * If this btree node is selected in btree_flush_write() by journal
+ * code, delay and retry until the node is flushed by journal code
+ * and BTREE_NODE_journal_flush bit cleared by btree_flush_write().
+ */
+ if (btree_node_journal_flush(b)) {
+ pr_debug("bnode %p is flushing by journal, retry", b);
+ mutex_unlock(&b->write_lock);
+ udelay(1);
+ goto retry;
+ }
+
if (btree_node_dirty(b))
__bch_btree_node_write(b, &cl);
mutex_unlock(&b->write_lock);
@@ -772,10 +800,15 @@
while (!list_empty(&c->btree_cache)) {
b = list_first_entry(&c->btree_cache, struct btree, list);
- if (btree_node_dirty(b))
+ /*
+ * This function is called by cache_set_free(), no I/O
+ * request on cache now, it is unnecessary to acquire
+ * b->write_lock before clearing BTREE_NODE_dirty anymore.
+ */
+ if (btree_node_dirty(b)) {
btree_complete_write(b, btree_current_write(b));
- clear_bit(BTREE_NODE_dirty, &b->flags);
-
+ clear_bit(BTREE_NODE_dirty, &b->flags);
+ }
mca_data_free(b);
}
@@ -1061,11 +1094,25 @@
BUG_ON(b == b->c->root);
+retry:
mutex_lock(&b->write_lock);
+ /*
+ * If the btree node is selected and flushing in btree_flush_write(),
+ * delay and retry until the BTREE_NODE_journal_flush bit cleared,
+ * then it is safe to free the btree node here. Otherwise this btree
+ * node will be in race condition.
+ */
+ if (btree_node_journal_flush(b)) {
+ mutex_unlock(&b->write_lock);
+ pr_debug("bnode %p journal_flush set, retry", b);
+ udelay(1);
+ goto retry;
+ }
- if (btree_node_dirty(b))
+ if (btree_node_dirty(b)) {
btree_complete_write(b, btree_current_write(b));
- clear_bit(BTREE_NODE_dirty, &b->flags);
+ clear_bit(BTREE_NODE_dirty, &b->flags);
+ }
mutex_unlock(&b->write_lock);
@@ -1470,11 +1517,11 @@
out_nocoalesce:
closure_sync(&cl);
- bch_keylist_free(&keylist);
while ((k = bch_keylist_pop(&keylist)))
if (!bkey_cmp(k, &ZERO_KEY))
atomic_dec(&b->c->prio_blocked);
+ bch_keylist_free(&keylist);
for (i = 0; i < nodes; i++)
if (!IS_ERR_OR_NULL(new_nodes[i])) {