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 $first_root_crypt  /p  btrfs  noatime,subvol=p  0 0
  73 EOF
  74         ;;
  75 esac
  76
  77 for vol in q p; do
  78     d=/$vol
  79     if ! awk '{print $2}' /etc/fstab | grep -xF $d &>/dev/null; then
  80         continue
  81     fi
  82
  83
  84     binds=()
  85     roots=($d)
  86     while true; do
  87         new_roots=()
  88         for r in ${roots[@]}; do
  89             # /q/a  /a  none  bind  0 0
  90             new_roots+=($(sed -rn "s#^$r/\S+\s+(\S+)\s+none\s+bind\s.*#\1#p" /etc/fstab))
  91         done
  92         (( ${#new_roots} )) || break
  93         binds+=(${new_roots[@]})
  94         roots=( ${new_roots[@]} )
  95     done
  96
  97     if e check-subvol-stale $d; then
  98         for b in ${binds[@]}; do
  99             mnt $b
 100         done
 101         continue
 102     fi
 103
 104     last_snap=$(</nocow/btrfs-stale/$vol)
 105     if [[ ! $last_snap ]]; then
 106         echo "$0: error. empty last_snap var"
 107         ret=1
 108         continue
 109     fi
 110
 111     umount_ret=true
 112     unmounted=()
 113     for dir in $(echo $d ${binds[*]}\ |tac -s\ ); do
 114         if mountpoint $dir; then
 115             if e umount -R $dir; then
 116                 unmounted+=($dir)
 117             else
 118                 umount_ret=false
 119                 echo "$0: failed to umount $dir"
 120                 break
 121             fi
 122         fi
 123     done
 124
 125     if ! $umount_ret; then
 126         for dir in ${unmounted[@]}; do
 127             mnt $dir
 128         done
 129         ret=1
 130         continue
 131     fi
 132
 133     cd /mnt/root
 134     if [[ -e $vol ]]; then
 135         e btrfs sub del $vol
 136     fi
 137     # Note, we make a few assumptions in this script, like
 138     # $d was not a different subvol id than $vol, and
 139     # things otherwise didn't get mounted very strangely.
 140     e btrfs sub snapshot btrbk/$last_snap $vol
 141     for dir in $d ${binds[@]}; do
 142         e mnt $dir
 143     done
 144 done
 145
 146 if [[ $HOSTNAME == treetowl ]]; then
 147     # partitioned it with fai partitioner outside of fai,
 148     # because it\'s worth it to have 1% space reserved for boot and
 149     # swap partitions in case I ever want to boot off those drives.
 150     # as root:
 151     # . /a/bin/fai/fai-wrapper
 152     # eval-fai-classfile /a/bin/fai/fai/config/class/51-multi-boot
 153     # fai-setclass ROTATIONAL
 154     # export LUKS_DIR=/q/root/luks/
 155     # # because the partition nums existed already
 156     # fai-setclass REPARTITION
 157     # /a/bin/fai/fai/config/hooks/partition.DEFAULT
 158
 159     devs=(
 160         ata-TOSHIBA_MD04ACA500_84REK6NTFS9A-part1
 161         ata-TOSHIBA_MD04ACA500_84R2K773FS9A-part1
 162         ata-TOSHIBA_MD04ACA500_8471K430FS9A-part1
 163         ata-TOSHIBA_MD04ACA500_8481K493FS9A-part1
 164     )
 165     first=true
 166     for dev in ${devs[@]}; do
 167         if $first; then
 168             first=false
 169             tu /etc/fstab <<EOF
 170 /dev/mapper/crypt_dev_$dev /i btrfs  noatime,subvol=i,noauto  0 0
 171 /dev/mapper/crypt_dev_$dev /mnt/iroot btrfs  noatime,subvolid=0,noauto  0 0
 172 EOF
 173         fi
 174         tu /etc/crypttab <<EOF
 175 crypt_dev_$dev  /dev/disk/by-id/$dev  /q/root/luks/host-treetowl  discard,luks
 176 EOF
 177         if [[ ! -e /dev/mapper/crypt_dev_$dev ]]; then
 178             cryptdisks_start crypt_dev_$dev
 179         fi
 180     done
 181 else
 182     tu /etc/fstab <<'EOF'
 183 /q/i  /i  none  bind,noauto  0 0
 184 EOF
 185 fi
 186
 187 exit $ret