From: Keith Busch <kbusch@xxxxxxxxxx>
Add a helper to wait for an entire chain of bios to complete.
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
[hch: split from a larger patch, moved and changed the name now that it
is non-static]
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
block/bio.c | 20 ++++++++++++++++++++
block/blk.h | 1 +
2 files changed, 21 insertions(+)
diff --git a/block/bio.c b/block/bio.c
index d82ef4fd545cb2..dce12a0efdead2 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1395,6 +1395,26 @@ int submit_bio_wait(struct bio *bio)
}
EXPORT_SYMBOL(submit_bio_wait);
+static void bio_wait_end_io(struct bio *bio)
+{
+ complete(bio->bi_private);
+ bio_put(bio);
+}
+
+/*
+ * bio_await_chain - ends @bio and waits for every chained bio to complete
+ */
+void bio_await_chain(struct bio *bio)
+{
+ DECLARE_COMPLETION_ONSTACK_MAP(done,
+ bio->bi_bdev->bd_disk->lockdep_map);
+
+ bio->bi_private = &done;
+ bio->bi_end_io = bio_wait_end_io;
+ bio_endio(bio);
+ blk_wait_io(&done);
+}
+
void __bio_advance(struct bio *bio, unsigned bytes)
{
if (bio_integrity(bio))
diff --git a/block/blk.h b/block/blk.h
index ee4f782d149662..d5107e65355e27 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -38,6 +38,7 @@ void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic);
void blk_queue_start_drain(struct request_queue *q);
int __bio_queue_enter(struct request_queue *q, struct bio *bio);
void submit_bio_noacct_nocheck(struct bio *bio);
+void bio_await_chain(struct bio *bio);
static inline bool blk_try_enter_queue(struct request_queue *q, bool pm)
{
--
2.39.2
