bcache: add code comments for bch_btree_node_get() and __bch_btree_node_alloc()

[ Upstream commit 31f5b956a197d4ec25c8a07cb3a2ab69d0c0b82f ]

This patch adds code comments to bch_btree_node_get() and
__bch_btree_node_alloc() that NULL pointer will not be returned and it
is unnecessary to check NULL pointer by the callers of these routines.

Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20231120052503.6122-10-colyli@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 3084c57..b709c2f 100644 (file)
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -995,6 +995,9 @@ err:
  *
  * The btree node will have either a read or a write lock held, depending on
  * level and op->lock.
+ *
+ * Note: Only error code or btree pointer will be returned, it is unncessary
+ *       for callers to check NULL pointer.
  */
 struct btree *bch_btree_node_get(struct cache_set *c, struct btree_op *op,
                                 struct bkey *k, int level, bool write,
@@ -1106,6 +1109,10 @@ retry:
        mutex_unlock(&b->c->bucket_lock);
 }
 
+/*
+ * Only error code or btree pointer will be returned, it is unncessary for
+ * callers to check NULL pointer.
+ */
 struct btree *__bch_btree_node_alloc(struct cache_set *c, struct btree_op *op,
                                     int level, bool wait,
                                     struct btree *parent)