From 9d0e8ada58e569020c27f300017d17319219bcf6 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei@redhat.com>
Date: Mon, 15 Nov 2021 19:53:38 +0800
Subject: [PATCH] dm: don't stop request queue after the dm device is suspended

mainline inclusion
from mainline-v5.16
commit a1c2f7e7f25c9d35d3bf046f99682c5373b20fa2
category: bugfix
bugzilla: 182378 https://gitee.com/openeuler/kernel/issues/I4DDEL

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a1c2f7e7f25c9d35d3bf046f99682c5373b20fa2

---------------------------

For fixing queue quiesce race between driver and block layer(elevator
switch, update nr_requests, ...), we need to support concurrent quiesce
and unquiesce, which requires the two call to be balanced.

__bind() is only called from dm_swap_table() in which dm device has been
suspended already, so not necessary to stop queue again. With this way,
request queue quiesce and unquiesce can be balanced.

Reported-by: Yi Zhang <yi.zhang@redhat.com>
Fixes: e70feb8b3e68 ("blk-mq: support concurrent queue quiesce/unquiesce")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>

Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
---
 drivers/md/dm.c | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 19a70f434029..3403722b1688 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2038,16 +2038,6 @@ static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t,
 
 	dm_table_event_callback(t, event_callback, md);
 
-	/*
-	 * The queue hasn't been stopped yet, if the old table type wasn't
-	 * for request-based during suspension.  So stop it to prevent
-	 * I/O mapping before resume.
-	 * This must be done before setting the queue restrictions,
-	 * because request-based dm may be run just after the setting.
-	 */
-	if (request_based)
-		dm_stop_queue(q);
-
 	if (request_based) {
 		/*
 		 * Leverage the fact that request-based DM targets are
-- 
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