iankelling.org Git - automated-distro-installer/blob - fresize

   1 #!/bin/bash
   2
   3 [[ $EUID == 0 ]] || exec sudo "$BASH_SOURCE" "$@"
   4
   5 x="$(readlink -f "$BASH_SOURCE")"; source "${x%/*}/bash-trace"
   6
   7 usage() {
   8     cat <<EOF
   9 Usage: ${0##*/} [OPTIONS] +/-SIZE[g] swap|boot
  10
  11 Assuming Ian Kelling's partition scheme and we are currently into one of
  12 it's encrypted oses (we it's btrfs filesystem to be mounted), resize
  13 swap or boot, expanding or shrinking the root fs and partition to
  14 compensate. If it changes the partition tables incorrectly, the
  15 originals are stored in /root/backup_partition_table_<device_names>.
  16
  17 TODO: only tested on stretch. deactivation of swap on reboot
  18 probably needs to be fixed on other oses. Even on stretch,
  19 we get 1.5 minutes of waiting for the crypt_dev and normal
  20 boot .device units.
  21
  22 Warning!!! Backup your data. This script could have bugs in it.
  23
  24 -n         Dry run. Note, this likely won't be the exact commands,
  25            for example, if you are running outside a vm, there will
  26            probably be a reboot required in the middle so the kernel
  27            can know about partition changes.
  28 -r         Reboot right away if it's needed.
  29 -f         Force running on a distro that has not been tested.
  30 -h|--help  Print help and exit.
  31
  32 SIZE is MiB, or if g is specified, GiB.
  33
  34 If using multiple devices, SIZE is applied to each device, so total change is
  35 SIZE * devices.
  36
  37 Note: Uses GNU getopt options parsing style
  38 EOF
  39     exit $1
  40 }
  41
  42 reboot_not=false
  43 dry_run=false
  44 force=false
  45
  46 temp=$(getopt -l help rnfh "$@") || usage 1
  47 eval set -- "$temp"
  48 while true; do
  49     case $1 in
  50         -r) reboot_now=true; shift ;;
  51         -n) dry_run=true; shift ;;
  52         -f) force=true; shift ;;
  53         -h|--help) usage ;;
  54         --) shift; break ;;
  55         *) echo "$0: Internal error!" ; exit 1 ;;
  56     esac
  57 done
  58
  59 #### begin arg error checking ####
  60
  61 if [[ $# != 2 ]]; then
  62     echo "$0: error: expected 2 arguments"
  63     usage 1
  64 fi
  65
  66 if [[ $1 != [+-][0-9]* ]]; then
  67     echo "$0: error: bad 1st arg: $1"
  68     usage 1
  69 fi
  70
  71 if ! which parted &>/dev/null; then
  72     echo "$0: error: install parted"
  73     exit 1
  74 fi
  75
  76 case $2 in swap|boot) : ;; *) echo "$0: error: bad 2nd arg"; usage 1 ;; esac
  77
  78 if ! $force && ! grep -q 'VERSION=.*stretch' /etc/os-release; then
  79     echo "$0: error: This distro is untested. Only tested version atm is Stretch."
  80     exit 1
  81 fi
  82
  83 #### end arg error checking ####
  84
  85
  86 boot=true
  87 [[ $2 == boot ]] || boot=false
  88
  89 op_size=$1 # operator plus size
  90 if [[ $op_size == *g ]]; then
  91     op_size=${op_size%g}
  92     size=${op_size#?}
  93     op=${op_size%$size}
  94     size=$(( $size * 1024 ))
  95     op_size=$op$size
  96 else
  97     size=${op_size#?}
  98 fi
  99
 100 if [[ $op_size == +* ]]; then
 101     op_size_rev=-$size # rev = reverse
 102     grow=true
 103 else
 104     op_size_rev=+$size
 105     grow=false
 106 fi
 107
 108 ##### end command line parsing ########
 109
 110 rootn=1
 111 swapn=2
 112 bootn=3
 113 needs_reboot=false
 114 reboot_script_initialized=false
 115
 116 pmk() { # partition make
 117     part=$1
 118     start_op=$2
 119     end_op=$3
 120     fs_type="$4"
 121
 122     # This fails outside a vm, but actually succeeds. also prints this
 123     # message:
 124     # Error: Partition(s) 2 on /dev/sda have been written, but
 125     # we have been unable to inform the kernel of the change, probably
 126     # because it/they are in use.  As a result, the old partition(s)
 127     # will remain in use.  You should reboot now before making further
 128     # changes.
 129
 130     if ! p mkpart primary "$fs_type" \
 131          $((${ptable[start$part]} $start_op)) $((${ptable[end$part]} $end_op)); then
 132         echo "$0: warning: ignoring failure return of mkpart"
 133     fi
 134 }
 135
 136 def-e() {
 137     if $dry_run; then
 138         e() { echo "+ $@"; }
 139     else
 140         e() { echo "+ $@"; "$@"; }
 141     fi
 142 }
 143
 144 def-e
 145
 146
 147 while read devid dev; do
 148     case $dev in
 149         /dev/dm-[0-9])
 150             # older oses, it points to /dev/dm-x
 151             dev=$(dmsetup info $dev | sed -rn 's/^\s*Name:\s*(\S*)/\1/p')
 152             ;;
 153         /dev/mapper/*)
 154             dev=${dev#/dev/mapper/}
 155             ;;
 156         *)
 157             echo "$0: error: could not find devicemapper root dev,
 158 make sure you are running from a encrypted root this script is resizing"
 159             exit 1
 160             ;;
 161     esac
 162     if [[ $dev != crypt_dev_*-part$rootn ]]; then
 163         echo "$0: error: unexpected root device name,
 164 make sure you are running from a encrypted root this script is resizing"
 165         exit 1
 166     fi
 167     dev=${dev#crypt_dev_}
 168     dev=${dev%-part$rootn}
 169     devpath=/dev/disk/by-id/$dev
 170     echo skip=$size
 171     def-e
 172     declare -A ptable
 173     while IFS=: read id start end psize _; do
 174         [[ $id == [0-9] ]] || continue
 175         ptable[start$id]=start=${start%%[^0-9]*}
 176         ptable[end$id]=${end%%[^0-9]*}
 177         ptable[size$id]=${psize%%[^0-9]*}
 178     done < <(parted -m $devpath unit MiB print)
 179     parted $devpath unit MiB print | tee /root/backup_partition_table_$dev
 180     p() { e parted -a optimal -s -- $devpath unit MiB "$@"; }
 181     unit=systemd-cryptsetup@crypt_dev_$dev-part$swapn
 182     # note systemctl show can test if a unit exists.
 183     if ! e systemctl stop $unit; then
 184         e swapoff -a
 185     fi
 186     # there is a bug in jessie. this and the .swap unit are
 187     # generated from /etc/fstab, and it escapes - to x2d, then doesn't escape it
 188     # when looking for the file to use as swap. so, no swap is working on jessie
 189     # right now.
 190     sleep 1 # dunno if this is needed,
 191     # but systemd likes to do these kind of things in the background.
 192
 193     # These partition comments seems a little verbose now, but I bet they
 194     # will be helpfull if I read this in more than a week from now.
 195     # <> = deleted partition, () = partition
 196     p rm $swapn # ( root )< swap >( boot )
 197
 198     root_resize_cmd="e btrfs fi resize $devid:${op_size_rev}M /"
 199     if $grow; then $root_resize_cmd; fi
 200     # if $grow; then
 201     # < root >< swap >( boot )
 202     # ( root ) >< swap >( boot )
 203     # else
 204     # < root >< swap >( boot )
 205     # ( root >< ) swap >( boot )
 206
 207     out=$(p rm $rootn 2>&1)
 208     echo "$out"
 209
 210     pmk $rootn "" $op_size_rev
 211
 212     if echo "$out" | \
 213             grep "but we have been unable to inform the kernel" &>/dev/null; then
 214         needs_reboot=true
 215     fi
 216     if $needs_reboot; then
 217         # note: even if these units don't exist, this will succeed.
 218         e systemctl mask dev-mapper-crypt_swap_$dev$swapn.swap
 219         e systemctl mask systemd-cryptsetup@crypt_swap_$dev$swapn.service
 220         e() { echo "$@" >> /root/finish-resize; }
 221         if ! $reboot_script_initialized; then
 222             reboot_script_initialized=true
 223             rm -rf /root/finish-resize
 224             cat >/root/finish-resize <<'EOF'
 225 #!/bin/bash -x
 226 set -eE -o pipefail
 227 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
 228 EOF
 229             chmod +x /root/finish-resize
 230         fi
 231         e swapoff -a
 232         e systemctl unmask systemd-cryptsetup@crypt_swap_$dev$swapn.service
 233         e systemctl unmask dev-mapper-crypt_swap_$dev$swapn.swap
 234     fi
 235     if ! $grow; then
 236         $root_resize_cmd
 237     fi
 238     if $boot; then
 239         # non by-id path, to match what btrfs fi show will tell us
 240         boot_dev_path=$(readlink -f $devpath-part$bootn)
 241         boot_devid=$(btrfs fi show /boot | \
 242                          sed -rn "s#^\s*devid\s+(\S+)\s.*$boot_dev_path#\1#p")
 243
 244         if ! $grow; then
 245             # shrink boot, move it to a temp file
 246             e btrfs fi resize $boot_devid:${op_size}M /boot
 247             e umount /boot
 248             temp_boot=/root/temp_boot_$dev
 249             e dd bs=1M if=$boot_dev_path of=$temp_boot \
 250               count=$((${ptable[size$bootn]} $op_size))
 251         else
 252             e umount /boot
 253         fi
 254         # if $grow; then
 255         # ( root ) >< swap >< boot >
 256         # ( root )( >< swap ) >< boot >
 257         # ( root )( >< swap )( >< boot )
 258         # else
 259         # ( root >< ) swap >< boot >
 260         # ( root >< )( swap >< ) boot >
 261         # ( root >< )( swap >< )( boot )
 262         p rm $bootn
 263         pmk $swapn $op_size_rev $op_size_rev "linux-swap"
 264         pmk $bootn $op_size_rev ""
 265
 266         if $grow; then
 267             e dd bs=1M if=$boot_dev_path of=$boot_dev_path skip=$size
 268             e mount /boot
 269             e btrfs fi resize $boot_devid:${op_size}M /boot
 270         else
 271             e dd bs=1M if=$temp_boot of=$boot_dev_path
 272             e mount /boot
 273         fi
 274     else
 275         # if $grow; then  ( root )( >< swap )( boot )
 276         # else            ( root >< )( swap )( boot )
 277         pmk $swapn $op_size_rev "" "linux-swap"
 278         e systemctl start systemd-cryptsetup@crypt_swap_$dev$swapn
 279     fi
 280 done < <(btrfs fi show / | sed -nr 's#^\s*devid\s*(\S+).* path (.*)$#\1 \2#p')
 281
 282
 283 if $boot; then
 284     e rm -rf "/root/temp_boot_*"
 285     e rm -f /root/finish-resize
 286 fi
 287
 288 if $needs_reboot; then
 289     echo "$0: Reboot, run /root/finish-resize. It's contents:"
 290     cat /root/finish-resize
 291     if $reboot_now; then
 292         echo "$0: rebooting now"
 293         reboot now
 294         exit
 295     fi
 296 fi