From: Milan Broz <mbroz@redhat.com>
Date: Tue, 6 Jan 2009 03:05:04 +0000 (+0000)
Subject: dm ioctl: allow dm_copy_name_and_uuid to return only one field
X-Git-Tag: v2.6.29-rc1~492^2~10
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=23d39f63aa87e812fd879b8bc32ee6ccfe733de3;p=linux-2.6-omap-h63xx.git

dm ioctl: allow dm_copy_name_and_uuid to return only one field

Allow NULL buffer in dm_copy_name_and_uuid if you only want to return one of
the fields.

(Required by a following patch that adds these fields to sysfs.)

Signed-off-by: Milan Broz <mbroz@redhat.com>
Reviewed-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 777c948180f..8da7a017b4e 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1550,8 +1550,10 @@ int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
 		goto out;
 	}
 
-	strcpy(name, hc->name);
-	strcpy(uuid, hc->uuid ? : "");
+	if (name)
+		strcpy(name, hc->name);
+	if (uuid)
+		strcpy(uuid, hc->uuid ? : "");
 
 out:
 	up_read(&_hash_lock);