From: Keith Busch <kbusch@kernel.org>
Date: Wed, 5 Jan 2022 09:05:16 -0800
Subject: [PATCH] block: introduce rq_list_for_each_safe macro
Git-commit: 3764fd05e1f89530e2ee5cbff0b638f2b1141b90
Patch-mainline: v5.17-rc1
References: jsc#PED-1183

While iterating a list, a particular request may need to be removed for
special handling. Provide an iterator that can safely handle that.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20220105170518.3181469-3-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 include/linux/blk-mq.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index bf64b94cd64e..1467f0fa2142 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -242,6 +242,10 @@ static inline unsigned short req_get_ioprio(struct request *req)
 #define rq_list_for_each(listptr, pos)			\
 	for (pos = rq_list_peek((listptr)); pos; pos = rq_list_next(pos))
 
+#define rq_list_for_each_safe(listptr, pos, nxt)			\
+	for (pos = rq_list_peek((listptr)), nxt = rq_list_next(pos);	\
+		pos; pos = nxt, nxt = pos ? rq_list_next(pos) : NULL)
+
 #define rq_list_next(rq)	(rq)->rq_next
 #define rq_list_empty(list)	((list) == (struct request *) NULL)
 
-- 
2.35.3