iankelling.org Git - distro-setup/blob - mount-latest-subvol

   1 #!/bin/bash
   2
   3 [[ $EUID == 0 ]] || exec sudo -E "$BASH_SOURCE" "$@"
   4
   5 errcatch() {
   6     set -E; shopt -s extdebug
   7     _err-trap() {
   8         err=$?
   9         exec >&2
  10         set +x
  11         echo "${BASH_SOURCE[1]}:${BASH_LINENO[0]}:in \`$BASH_COMMAND' returned $err"
  12         bash-trace 2
  13         echo "$0: exiting with code $err"
  14         exit $err
  15     }
  16     trap _err-trap ERR
  17     set -o pipefail
  18 }
  19 bash-trace() {
  20     local -i argc_index=0 arg frame i start=${1:-1} max_indent=8 indent
  21     local source
  22     local extdebug=false
  23     if [[ $(shopt -p extdebug) == *-s* ]]; then
  24         extdebug=true
  25     fi
  26
  27     for ((frame=0; frame < ${#FUNCNAME[@]}-1; frame++)); do
  28         argc=${BASH_ARGC[frame]}
  29         argc_index+=$argc
  30         ((frame < start)) && continue
  31         if (( ${#BASH_SOURCE[@]} > 1 )); then
  32             source="${BASH_SOURCE[frame+1]}:${BASH_LINENO[frame]}:"
  33         fi
  34         indent=$((frame-start+1))
  35         indent=$((indent < max_indent ? indent : max_indent))
  36         printf "%${indent}s↳%sin \`%s" '' "$source" "${FUNCNAME[frame]}"
  37         if $extdebug; then
  38             for ((i=argc_index-1; i >= argc_index-argc; i--)); do
  39                 printf " %s" "${BASH_ARGV[i]}"
  40             done
  41         fi
  42         echo \'
  43     done
  44 }
  45 errcatch
  46
  47 tu() {
  48     while read -r line; do
  49         file="$1"
  50         grep -xFq "$line" "$file" || tee -a "$file"<<<"$line"
  51     done
  52 }
  53 e() { printf "%s\n" "$*"; "$@"; }
  54 mnt() {
  55     dir=$1
  56     if ! mountpoint $dir >/dev/null; then
  57         mkdir -p $dir
  58         e mount $dir
  59     fi
  60 }
  61
  62 ret=0
  63
  64 first_root_crypt=$(awk '$2 == "/" {print $1}' /etc/mtab)
  65 tu /etc/fstab <<EOF
  66 $first_root_crypt  /q  btrfs  noatime,subvol=q  0 0
  67 /q/a  /a  none  bind  0 0
  68 EOF
  69 case $HOSTNAME in
  70     treetowl|x2|frodo)
  71         tu /etc/fstab <<EOF
  72 $first_root_crypt  /p  btrfs  noatime,subvol=p  0 0
  73 EOF
  74         ;;
  75 esac
  76 if [[ $HOSTNAME == treetowl ]]; then
  77     # partitioned it with fai partitioner outside of fai,
  78     # because it\'s worth it to have 1% space reserved for boot and
  79     # swap partitions in case I ever want to boot off those drives.
  80     # as root:
  81     # . /a/bin/fai/fai-wrapper
  82     # eval-fai-classfile /a/bin/fai/fai/config/class/51-multi-boot
  83     # fai-setclass ROTATIONAL
  84     # export LUKS_DIR=/q/root/luks/
  85     # # because the partition nums existed already
  86     # fai-setclass REPARTITION
  87     # /a/bin/fai/fai/config/hooks/partition.DEFAULT
  88
  89     # just the first in the btrfs raid
  90     dev=ata-TOSHIBA_MD04ACA500_84REK6NTFS9A-part1
  91     tu /etc/fstab <<EOF
  92 /dev/mapper/crypt_dev_$dev /i btrfs  noatime,subvol=i  0 0
  93 EOF
  94     tu /etc/crypttab <<EOF
  95 crypt_dev_$dev  /dev/disk/by-id/$dev  /q/root/luks/host-treetowl  discard,luks
  96 EOF
  97
  98 else
  99     tu /etc/fstab <<'EOF'
 100 /q/i  /i  none  bind  0 0
 101 EOF
 102
 103 fi
 104
 105 for vol in q p; do
 106     d=/$vol
 107     if ! awk '{print $2}' /etc/fstab | grep -xF $d &>/dev/null; then
 108         continue
 109     fi
 110
 111
 112     binds=()
 113     roots=($d)
 114     while true; do
 115         new_roots=()
 116         for r in ${roots[@]}; do
 117             # /q/a  /a  none  bind  0 0
 118             new_roots+=($(sed -rn "s#^$r/\S+\s+(\S+)\s+none\s+bind\s.*#\1#p" /etc/fstab))
 119         done
 120         (( ${#new_roots} )) || break
 121         binds+=(${new_roots[@]})
 122         roots=( ${new_roots[@]} )
 123     done
 124
 125     if e check-subvol-stale $d; then
 126         for b in ${binds[@]}; do
 127             mnt $b
 128         done
 129         continue
 130     fi
 131
 132     last_snap=$(</nocow/btrfs-stale/$vol)
 133     if [[ ! $last_snap ]]; then
 134         echo "$0: error. empty last_snap var"
 135         ret=1
 136         continue
 137     fi
 138
 139     umount_ret=true
 140     unmounted=()
 141     for dir in $(echo $d ${binds[*]}\ |tac -s\ ); do
 142         if mountpoint $dir; then
 143             if e umount -R $dir; then
 144                 unmounted+=($dir)
 145             else
 146                 umount_ret=false
 147                 echo "$0: failed to umount $dir"
 148                 break
 149             fi
 150         fi
 151     done
 152
 153     if ! $umount_ret; then
 154         for dir in ${unmounted[@]}; do
 155             mnt $dir
 156         done
 157         ret=1
 158         continue
 159     fi
 160
 161     cd /mnt/root
 162     if [[ -e $vol ]]; then
 163         e btrfs sub del $vol
 164     fi
 165     # Note, we make a few assumptions in this script, like
 166     # $d was not a different subvol id than $vol, and
 167     # things otherwise didn't get mounted very strangely.
 168     e btrfs sub snapshot btrbk/$last_snap $vol
 169     for dir in $d ${binds[@]}; do
 170         e mnt $dir
 171     done
 172 done
 173 exit $ret