[PATCH 04/12] btrfs: create a helper function, check_fsid(), to verify the tempfsid

From: Anand Jain <anand.jain@oracle.com>
To: fstests@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Subject: [PATCH 04/12] btrfs: create a helper function, check_fsid(), to verify the tempfsid
Date: Thu, 15 Feb 2024 14:34:07 +0800	[thread overview]
Message-ID: <cd8342fb284a1983d7645698464debecf417e52a.1707969354.git.anand.jain@oracle.com> (raw)
In-Reply-To: <cover.1707969354.git.anand.jain@oracle.com>

check_fsid() provides a method to verify if the given device is mounted
with the tempfsid in the kernel. Function sb() is an internal only
function.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
 common/btrfs | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/common/btrfs b/common/btrfs
index e1b29c613767..5cba9b16b4de 100644
--- a/common/btrfs
+++ b/common/btrfs
@@ -792,3 +792,37 @@ _has_btrfs_sysfs_feature_attr()
 
 	test -e /sys/fs/btrfs/features/$feature_attr
 }
+
+# Dump key members of the on-disk super-block from the given disk; helps debug
+sb()
+{
+	local dev1=$1
+	local parameters="device|devid|^metadata_uuid|^fsid|^incom|^generation|\
+		^flags| \|$| \)$|compat_flags|compat_ro_flags|dev_item.uuid"
+
+	$BTRFS_UTIL_PROG inspect-internal dump-super $dev1 | egrep "$parameters"
+}
+
+check_fsid()
+{
+	local dev1=$1
+	local fsid
+
+	# on disk fsid
+	fsid=$(sb $dev1 | grep ^fsid | awk -d" " '{print $2}')
+	echo -e "On disk fsid:\t\t$fsid" | sed -e "s/$fsid/FSID/g"
+
+	echo -e -n "Metadata uuid:\t\t"
+	cat /sys/fs/btrfs/$fsid/metadata_uuid | sed -e "s/$fsid/FSID/g"
+
+	# This returns the temp_fsid if set
+	tempfsid=$(_btrfs_get_fsid $dev1)
+	if [[ $tempfsid == $fsid ]]; then
+		echo -e "Temp fsid:\t\tFSID"
+	else
+		echo -e "Temp fsid:\t\tTEMPFSID"
+	fi
+
+	echo -e -n "Tempfsid status:\t"
+	cat /sys/fs/btrfs/$tempfsid/temp_fsid
+}
-- 
2.39.3

