X-Git-Url: https://iankelling.org/git/?p=distro-setup;a=blobdiff_plain;f=mount-latest-subvol;h=359b534337669090503de236c2ab30467c35b4dd;hp=bf5ec9c844e27221d0a91548dfc834f16fdb6b05;hb=0b6d44c7f3d567e0a26138509c8a24cb57c69b50;hpb=b38f62582694bd678baa77bfeab627feefbc6a40

diff --git a/mount-latest-subvol b/mount-latest-subvol
index bf5ec9c..359b534 100644
--- a/mount-latest-subvol
+++ b/mount-latest-subvol
@@ -14,7 +14,11 @@
 # limitations under the License.
 
 # usage: mount-latest-subvol
+#
+# Note, at source location, intentionally not executable, run and read
+# install-my-scripts.
 
+cd /
 [[ $EUID == 0 ]] || exec sudo -E "$BASH_SOURCE" "$@"
 
 errcatch() {
@@ -81,6 +85,17 @@ fstab() {
     tu /etc/fstab <<<"$l"
   done
 }
+pid-check() {
+  for p in ${pids}; do
+    for m in ${my_pids[@]}; do
+      if (( p == m )); then
+        echo "$0: error: pids to kill includes our pid or a parent. ps output:" >&2
+        ps -f -p $p
+        exit 1
+      fi
+    done
+  done
+}
 kill-dir() {
   for sig; do
     echo kill-dir $sig
@@ -88,11 +103,13 @@ kill-dir() {
     if pids=$(timeout 4 lsof -t $dir); then
       found_pids=true
       timeout 4 lsof -w $dir
+      pid-check
       kill -$sig $pids
     fi
     # fuser will find open sockets that lsof won't, for example from gpg-agent.
     # note: -v shows kernel processes, which then doesn't return true when we want
-    if timeout 4 fuser -m $dir &>/dev/null; then
+    if pids=$(timeout 4 fuser -m $dir 2>/dev/null); then
+      pid-check
       found_pids=true
       fuser -$sig -mvk $dir
     fi
@@ -112,9 +129,32 @@ fi
 ret=0
 
 ##### begin setup fstab for subvols we care about ######
-first_root_crypt=$(awk '$2 == "/" {print $1}' /etc/mtab)
+root_dev=$(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
+else # if we are in a recovery boot, find the next best crypt device
+  noauto=,noauto
+  for dev in $(dmsetup ls --target crypt | awk '{print $1}'); do
+    dev=/dev/mapper/$dev
+    if awk '{print $1}' /etc/mtab | grep -Fx $dev &>/dev/null; then
+      crypt_dev=$dev
+      break
+    fi
+  done
+fi
+
+
 fstab <<EOF
-$first_root_crypt  /a  btrfs  noatime,subvol=a  0 0
+$crypt_dev  /a  btrfs  noatime,subvol=a$noauto  0 0
 EOF
 
 shopt -s nullglob
@@ -126,26 +166,40 @@ shopt -s nullglob
 f=(/mnt/root/btrbk/q.*)
 if [[ -e $f ]]; then
   fstab <<EOF
-$first_root_crypt  /q  btrfs  noatime,subvol=q,gid=1000  0 0
-/q/p  /p  none  bind  0 0
+$crypt_dev  /q  btrfs  noatime,subvol=q,gid=1000$noauto  0 0
+/q/p  /p  none  bind$noauto  0 0
 EOF
 fi
 
 f=(/mnt/root/btrbk/o.*)
 if [[ -e $f ]]; then
   fstab <<EOF
-$first_root_crypt  /o  btrfs  noatime,subvol=o  0 0
-/o/m  /m  none  bind  0 0
+$crypt_dev  /o  btrfs  noatime,subvol=o$noauto  0 0
+/o/m  /m  none  bind$noauto  0 0
 EOF
 fi
 
 if [[ $HOSTNAME == frodo ]]; then
   fstab <<EOF
-$first_root_crypt  /i  btrfs  noatime,subvol=i  0 0
+$crypt_dev  /i  btrfs  noatime,subvol=i$noauto  0 0
 EOF
 fi
 ##### end setup fstab for subvols we care about ######
 
+# get pids that this program depends on so we dont kill them
+my_pids=($$ $PPID)
+loop_limit=30
+count=0
+while [[ ${my_pids[-1]} != 1 && ${my_pids[-1]} != ${my_pids[-2]} && $count -lt $loop_limit  ]]; do
+  count=$((count + 1))
+  p=$(ps -p ${my_pids[-1]} -o ppid=)
+  if [[ $p == 0 || ! $p ]]; then
+    break
+  fi
+  my_pids+=($p)
+done
+
+
 for vol in q a o i; do
   d=/$vol
   if ! awk '{print $2}' /etc/fstab | grep -xF $d &>/dev/null; then
@@ -172,7 +226,9 @@ for vol in q a o i; do
 
 
   # if latest is already mounted, make sure binds are mounted and move on
-  if e check-subvol-stale $d; then
+  e check-subvol-stale $d
+  # populated by check-subvol-stale if stale
+  if ! fresh_snap=$(cat /nocow/btrfs-stale/$vol 2>/dev/null); then
     mnt $d
     for b in ${binds[@]}; do
       mnt $b
@@ -180,13 +236,6 @@ for vol in q a o i; do
     continue
   fi
 
-  fresh_snap=$(</nocow/btrfs-stale/$vol)
-  if [[ ! $fresh_snap ]]; then
-    echo "$0: error. empty fresh_snap var"
-    ret=1
-    continue
-  fi
-
   umount_ret=true
   unmounted=()
   for dir in $(echo $d ${binds[*]}\ |tac -s\ ); do