Received-SPF: pass (google.com: domain of linux-kernel+bounces-80464-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
From: linan666@huaweicloud.com
To: song@kernel.org,
	shli@fb.com,
	neilb@suse.com
Cc: mariusz.tkaczyk@linux.intel.com,
	linux-raid@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	linan666@huaweicloud.com,
	yukuai3@huawei.com,
	yi.zhang@huawei.com,
	houtao1@huawei.com,
	yangerkun@huawei.com
Subject: [PATCH v7 5/9] md: Don't clear MD_CLOSING when the raid is about to stop
Date: Mon, 26 Feb 2024 11:14:40 +0800
Message-Id: <20240226031444.3606764-6-linan666@huaweicloud.com>
In-Reply-To: <20240226031444.3606764-1-linan666@huaweicloud.com>
References: <20240226031444.3606764-1-linan666@huaweicloud.com>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

From: Li Nan <linan122@huawei.com>

The raid should not be opened anymore when it is about to be stopped.
However, other processes can open it again if the flag MD_CLOSING is
cleared before exiting. From now on, this flag will not be cleared when
the raid will be stopped.

Fixes: 065e519e71b2 ("md: MD_CLOSING needs to be cleared after called md_set_readonly or do_md_stop")
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
---
 drivers/md/md.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 08b0f80274c0..43ca8a4c02ce 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6264,7 +6264,15 @@ static void md_clean(struct mddev *mddev)
 	mddev->persistent = 0;
 	mddev->level = LEVEL_NONE;
 	mddev->clevel[0] = 0;
-	mddev->flags = 0;
+	/*
+	 * Don't clear MD_CLOSING, or mddev can be opened again.
+	 * 'hold_active != 0' means mddev is still in the creation
+	 * process and will be used later.
+	 */
+	if (mddev->hold_active)
+		mddev->flags = 0;
+	else
+		mddev->flags &= BIT_ULL_MASK(MD_CLOSING);
 	mddev->sb_flags = 0;
 	mddev->ro = MD_RDWR;
 	mddev->metadata_type[0] = 0;
@@ -7602,7 +7610,6 @@ static int md_ioctl(struct block_device *bdev, blk_mode_t mode,
 	int err = 0;
 	void __user *argp = (void __user *)arg;
 	struct mddev *mddev = NULL;
-	bool did_set_md_closing = false;
 
 	err = md_ioctl_valid(cmd);
 	if (err)
@@ -7659,7 +7666,6 @@ static int md_ioctl(struct block_device *bdev, blk_mode_t mode,
 			mutex_unlock(&mddev->open_mutex);
 			return -EBUSY;
 		}
-		did_set_md_closing = true;
 		mutex_unlock(&mddev->open_mutex);
 		sync_blockdev(bdev);
 	}
@@ -7801,7 +7807,7 @@ static int md_ioctl(struct block_device *bdev, blk_mode_t mode,
 				     mddev_unlock(mddev);
 
 out:
-	if(did_set_md_closing)
+	if (cmd == STOP_ARRAY_RO || (err && cmd == STOP_ARRAY))
 		clear_bit(MD_CLOSING, &mddev->flags);
 	return err;
 }
-- 
2.39.2