From 3174b9cb665b9a7b7ac8413a8e236cd236786632 Mon Sep 17 00:00:00 2001
From: Ian Kelling <iank@fsf.org>
Date: Tue, 16 Apr 2019 16:23:22 -0400
Subject: [PATCH] fixes for initial fstab mtab dm devices

---
 check-subvol-stale  | 3 ++-
 mount-latest-subvol | 9 ++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/check-subvol-stale b/check-subvol-stale
index 0049ff0..cc032d4 100644
--- a/check-subvol-stale
+++ b/check-subvol-stale
@@ -82,6 +82,7 @@ for d; do
   vol=${d##*/}
   # second field, non-comment line == $d
   dev=$(sed -rn "s,^\s*([^#]\S*)\s+$d\s.*,\1,p" /etc/fstab /etc/mtab|head -n1)
+
   d dev=$dev
   subvol_dir=$(sed -rn "s,^\s*[^#]\S*\s+$d\s.*\bsubvol=([a-zA-A/]+).*,\1,p" /etc/fstab /etc/mtab|head -n1)
   d subvol_dir=$subvol_dir
@@ -89,7 +90,7 @@ for d; do
   # because the device in fstab for the rootfs can be different.
   for devx in $(btrfs fi show $dev| sed -rn 's#.*path (/\S+)$#\1#p'); do
     d devx=$devx
-    root_dir=$(sed -rn "s,^\s*$devx\s+(\S+).*\bsubvolid=[05]\b.*,\1,p" /etc/mtab|head -n1)
+    root_dir=$(sed -rn "s,^\s*$devx\s+(\S+).*\bsubvolid=[05]\b.*,\1,p" /etc/mtab /etc/fstab|head -n1)
     if [[ $root_dir ]]; then
       d root_dir=$root_dir
       break
diff --git a/mount-latest-subvol b/mount-latest-subvol
index 033d9b8..359b534 100644
--- a/mount-latest-subvol
+++ b/mount-latest-subvol
@@ -130,7 +130,14 @@ ret=0
 
 ##### begin setup fstab for subvols we care about ######
 root_dev=$(awk '$2 == "/" {print $1}' /etc/mtab)
-
+if [[ $root_dev == /dev/dm-* ]]; then
+  for d in /dev/mapper/*; do
+    if [[ $(readlink -f $d) == $root_dev ]]; then
+      root_dev=$d
+      break
+    fi
+  done
+fi
 
 if cryptsetup status $root_dev &>/dev/null; then
   crypt_dev=$root_dev
-- 
2.30.2