md: use new apis to suspend array for adding/removing rdev from state_store()

User can write 'remove' and 're-add' to trigger array reconfiguration
through sysfs, suspend array in this case so that io won't concurrent
with array reconfiguration.

And now that all the caller of add_bound_rdev() alread suspend the
array, remove mddev_suspend/resume() from add_bound_rdev() as well.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231010151958.145896-12-yukuai1@huaweicloud.com

drivers/md/md.c

@@ -2940,11 +2940,7 @@ static int add_bound_rdev(struct md_rdev *rdev)
 		 */
 		super_types[mddev->major_version].
 			validate_super(mddev, rdev);
-		if (add_journal)
-			mddev_suspend(mddev);
 		err = mddev->pers->hot_add_disk(mddev, rdev);
-		if (add_journal)
-			mddev_resume(mddev);
 		if (err) {
 			md_kick_rdev_from_array(rdev);
 			return err;
@@ -3697,6 +3693,7 @@ rdev_attr_store(struct kobject *kobj, struct attribute *attr,
 	struct rdev_sysfs_entry *entry = container_of(attr, struct rdev_sysfs_entry, attr);
 	struct md_rdev *rdev = container_of(kobj, struct md_rdev, kobj);
 	struct kernfs_node *kn = NULL;
+	bool suspend = false;
 	ssize_t rv;
 	struct mddev *mddev = rdev->mddev;
 
@@ -3704,17 +3701,23 @@ rdev_attr_store(struct kobject *kobj, struct attribute *attr,
 		return -EIO;
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
+	if (!mddev)
+		return -ENODEV;
 
-	if (entry->store == state_store && cmd_match(page, "remove"))
+	if (entry->store == state_store) {
+		if (cmd_match(page, "remove"))
 			kn = sysfs_break_active_protection(kobj, attr);
+		if (cmd_match(page, "remove") || cmd_match(page, "re-add"))
+			suspend = true;
+	}
 
-	rv = mddev ? mddev_lock(mddev) : -ENODEV;
+	rv = suspend ? mddev_suspend_and_lock(mddev) : mddev_lock(mddev);
 	if (!rv) {
 		if (rdev->mddev == NULL)
 			rv = -ENODEV;
 		else
 			rv = entry->store(rdev, page, length);
-		mddev_unlock(mddev);
+		suspend ? mddev_unlock_and_resume(mddev) : mddev_unlock(mddev);
 	}
 
 	if (kn)