block: move blk_steal_bios to blk-mq.c

Keep all the request based code together.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20211117061404.331732-8-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 21 insertions, 0 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 3217139d2e0b..cd5f31c4d2fd 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3014,6 +3014,27 @@ free_and_out:
 }
 EXPORT_SYMBOL_GPL(blk_rq_prep_clone);
 
+/*
+ * Steal bios from a request and add them to a bio list.
+ * The request must not have been partially completed before.
+ */
+void blk_steal_bios(struct bio_list *list, struct request *rq)
+{
+	if (rq->bio) {
+		if (list->tail)
+			list->tail->bi_next = rq->bio;
+		else
+			list->head = rq->bio;
+		list->tail = rq->biotail;
+
+		rq->bio = NULL;
+		rq->biotail = NULL;
+	}
+
+	rq->__data_len = 0;
+}
+EXPORT_SYMBOL_GPL(blk_steal_bios);
+
 static size_t order_to_size(unsigned int order)
 {
 	return (size_t)PAGE_SIZE << order;