From: Yu Kuai <yukuai3@huawei.com>
Date: Tue, 6 May 2025 12:49:00 +0000 (+0800)
Subject: md: record dm-raid gendisk in mddev
X-Git-Tag: for-6.16/block-20250523~31^2~3
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=7168be3c8a6b76ba10a51615a5bdf985dd502226;p=linux-block.git

md: record dm-raid gendisk in mddev

Following patch will use gendisk to check if there are normal IO
completed or inflight, to fix a problem in mdraid that foreground IO
can be starved by background sync IO in later patches.

Link: https://lore.kernel.org/linux-raid/20250506124903.2540268-7-yukuai1@huaweicloud.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
---

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 6adc55fd90d3..127138c61be5 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -14,6 +14,7 @@
 #include "raid5.h"
 #include "raid10.h"
 #include "md-bitmap.h"
+#include "dm-core.h"
 
 #include <linux/device-mapper.h>
 
@@ -3308,6 +3309,7 @@ size_check:
 
 	/* Disable/enable discard support on raid set. */
 	configure_discard_support(rs);
+	rs->md.dm_gendisk = ti->table->md->disk;
 
 	mddev_unlock(&rs->md);
 	return 0;
@@ -3327,6 +3329,7 @@ static void raid_dtr(struct dm_target *ti)
 
 	mddev_lock_nointr(&rs->md);
 	md_stop(&rs->md);
+	rs->md.dm_gendisk = NULL;
 	mddev_unlock(&rs->md);
 
 	if (work_pending(&rs->md.event_work))
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 1cf00a04bcdd..9d55b4630077 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -404,7 +404,8 @@ struct mddev {
 						       * are happening, so run/
 						       * takeover/stop are not safe
 						       */
-	struct gendisk			*gendisk;
+	struct gendisk			*gendisk;    /* mdraid gendisk */
+	struct gendisk			*dm_gendisk; /* dm-raid gendisk */
 
 	struct kobject			kobj;
 	int				hold_active;