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

   1 #!/bin/bash
   2 # Copyright (C) 2016 Ian Kelling
   3 #
   4 # Licensed under the Apache License, Version 2.0 (the "License");
   5 # you may not use this file except in compliance with the License.
   6 # You may obtain a copy of the License at
   7 #
   8 #     http://www.apache.org/licenses/LICENSE-2.0
   9 #
  10 # Unless required by applicable law or agreed to in writing, software
  11 # distributed under the License is distributed on an "AS IS" BASIS,
  12 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 # See the License for the specific language governing permissions and
  14 # limitations under the License.
  15
  16 script=$(readlink -f -- "$BASH_SOURCE")
  17 cd /
  18 [[ $EUID == 0 ]] || exec sudo -E "$script" "$@"
  19
  20 source /usr/local/lib/err
  21
  22 usage() {
  23   cat <<EOF
  24 Usage: ${0##*/} [OPTIONS]
  25
  26 -h|--help  Print help and exit.
  27 -f|--force  Use kill -9 to try fixing unmount errors
  28 -v|--verbose  Be more verbose
  29
  30
  31 Note, at source location, intentionally not executable, run and read
  32 install-my-scripts.
  33
  34 Note: Uses util-linux getopt option parsing: spaces between args and
  35 options, short options can be combined, options before args.
  36 EOF
  37   exit $1
  38 }
  39
  40 all_vols=(q a o i ar qr)
  41
  42
  43 tu() {
  44   while read -r line; do
  45     file="$1"
  46     grep -xFq "$line" "$file" || tee -a "$file"<<<"$line"
  47   done
  48 }
  49 d() {
  50   if $verbose; then
  51     printf "%s\n" "$*"
  52   fi
  53 }
  54 m() {
  55   if $verbose; then
  56     printf "%s\n" "$*"
  57   fi
  58   "$@"
  59 }
  60 x() {
  61   printf "%s\n" "$*"
  62   "$@"
  63 }
  64
  65 mnt() {
  66   dir=$1
  67   if ! mountpoint -q $dir; then
  68     mkdir -p $dir
  69     m mount $dir
  70   fi
  71 }
  72 fstab() {
  73   while read -r start mpoint end; do
  74     l="$start $mpoint $end"
  75     # kill off any lines that duplicate the mount point.
  76     sed --follow-symlinks -ri "\%$l%b;\%^\s*\S+\s+$mpoint\s%d" /etc/fstab
  77     tu /etc/fstab <<<"$l"
  78   done
  79 }
  80 pid-check() {
  81   for p in ${pids}; do
  82     for m in ${my_pids[@]}; do
  83       if (( p == m )); then
  84         echo "$0: error: pids to kill includes our pid or a parent. ps output:" >&2
  85         ps -f -p $p
  86         exit 1
  87       fi
  88     done
  89   done
  90 }
  91 kill-dir() {
  92   for sig; do
  93     echo kill-dir $sig
  94     found_pids=false
  95     if pids=$(timeout 4 lsof -t $dir); then
  96       found_pids=true
  97       timeout 4 lsof -w $dir
  98       pid-check
  99       kill -$sig $pids
 100     fi
 101     # fuser will find open sockets that lsof won't, for example from gpg-agent.
 102     # note: -v shows kernel processes, which then doesn't return true when we want
 103     if pids=$(timeout 4 fuser -m $dir 2>/dev/null); then
 104       pid-check
 105       found_pids=true
 106       fuser -$sig -mvk $dir
 107     fi
 108     sleep .5
 109     if ! $found_pids; then
 110       return 0
 111     fi
 112   done
 113   return 1
 114 }
 115 umount-kill() {
 116   dir=$1
 117   if mountpoint -q $dir; then
 118     if m umount -R $dir; then
 119       unmounted+=($dir)
 120     else
 121       if ! kill-dir TERM TERM TERM INT INT HUP HUP TERM TERM TERM INT INT HUP HUP; then
 122         if $force; then  kill-dir KILL; fi
 123       fi
 124
 125       if m umount -R $dir; then
 126         unmounted+=($dir)
 127       else
 128         echo "$0: failed to umount $dir"
 129         umount_ret=false
 130         ret=1
 131       fi
 132     fi
 133   fi
 134 }
 135
 136 # duplicated in check-subvol
 137 # Reassign $1 var from /dev/dm- to corresponding /dev/mapper/
 138 mapper-dev() {
 139   local mapdev
 140   local -n devref=$1
 141   if [[ $devref == /dev/dm-* ]]; then
 142     for mapdev in /dev/mapper/*; do
 143       if [[ $(readlink -f $mapdev) == "$devref" ]]; then
 144         devref=$mapdev
 145         break
 146       fi
 147     done
 148   fi
 149 }
 150
 151
 152 ##### begin command line parsing ########
 153
 154 # you can remove this if you do not have options which can have args with spaces or empty.
 155
 156 verbose=true
 157 force=false
 158 temp=$(getopt -l help,force,verbose hfv "$@") || usage 1
 159 eval set -- "$temp"
 160 while true; do
 161   case $1 in
 162     -f|--force) force=true ;;
 163     -v|--verbose) verbose=true ;;
 164     -h|--help) usage ;;
 165     --) shift; break ;;
 166     *) echo "$0: unexpected args: $*" >&2 ; usage 1 ;;
 167   esac
 168   shift
 169 done
 170
 171 ##### end command line parsing ########
 172
 173 ret=0
 174
 175 ##### begin setup fstab for subvols we care about ######
 176
 177 if [[ -e /mnt/root/root2-crypttab ]]; then
 178   tu /etc/crypttab </mnt/root/root2-crypttab
 179   while read -r mapper_dev _; do
 180     if [[ ! -e /dev/mapper/$mapper_dev ]]; then
 181       m cryptdisks_start $mapper_dev
 182     fi
 183   done < <(cat /mnt/root/root2-crypttab)
 184 fi
 185 if [[ -e /mnt/root/root2-fstab ]]; then
 186   tu /etc/fstab </mnt/root/root2-fstab
 187   mnt /mnt/root2
 188   mnt /mnt/boot2
 189 fi
 190
 191 do_o=true
 192 root_dev=$(awk '$2 == "/" {print $1}' /etc/mtab)
 193 mapper-dev root_dev
 194 o_dev=$(awk '$2 == "/mnt/o" {print $1}' /etc/mtab)
 195 mapper-dev o_dev
 196
 197 if [[ $o_dev == "$root_dev" ]]; then
 198   do_o=false
 199 fi
 200
 201 # root2_dev=$(awk '$2 == "/mnt/root2" {print $1}' /etc/mtab)
 202 # mapper-dev root2_dev
 203 # # dont bother with the above for crypt2_dev
 204 # crypt2_dev=$root2_dev
 205
 206
 207 if cryptsetup status $root_dev &>/dev/null; then
 208   crypt_dev=$root_dev
 209 else # if we are in a recovery boot, find the next best crypt device
 210   mopts=,noauto
 211   do_o=false
 212   for dev in $(dmsetup ls --target crypt | awk '{print $1}'); do
 213     dev=/dev/mapper/$dev
 214     if awk '{print $1}' /etc/mtab | grep -Fx $dev &>/dev/null; then
 215       crypt_dev=$dev
 216       break
 217     fi
 218   done
 219 fi
 220
 221
 222
 223 # dont tax the cpus of old laptops
 224 if ((`nproc` > 2)); then
 225   mopts+=,compress=zstd
 226 fi
 227
 228 fstab <<EOF
 229 $crypt_dev  /a  btrfs  noatime,subvol=a$mopts  0 0
 230 EOF
 231
 232 shopt -s nullglob
 233
 234 # ssh and probably some other things care about parent directory
 235 # ownership, and ssh doesn\'t allow any group writable parent
 236 # directories, so we are forced to use a directory structure similar
 237 # to home directories
 238 f=(/mnt/root/btrbk/q.*); f=${f[0]}
 239 if [[ -e $f ]]; then
 240   fstab <<EOF
 241 $crypt_dev  /q  btrfs  noatime,subvol=q,gid=1000$mopts  0 0
 242 /q/p  /p  none  bind$mopts  0 0
 243 EOF
 244 fi
 245
 246 f=(/mnt/o/btrbk/o.*); f=${f[0]}
 247 if [[ -e $f ]]; then
 248   fstab <<EOF
 249 $o_dev  /o  btrfs  noatime,subvol=o$mopts  0 0
 250 /o/m  /m  none  bind$mopts  0 0
 251 EOF
 252 else
 253   do_o=false
 254 fi
 255
 256 if [[ $HOSTNAME == frodo ]]; then
 257   fstab <<EOF
 258 $crypt_dev  /i  btrfs  noatime,subvol=i$mopts  0 0
 259 EOF
 260 fi
 261
 262
 263
 264 ##### end setup fstab for subvols we care about ######
 265
 266 ### begin get pids that this program depends on so we dont kill them
 267 my_pids=($$ $PPID)
 268 loop_limit=30
 269 count=0
 270 while [[ ${my_pids[-1]} != 1 && ${my_pids[-1]} != ${my_pids[-2]} && $count -lt $loop_limit  ]]; do
 271   count=$((count + 1))
 272   p=$(ps -p ${my_pids[-1]} -o ppid=)
 273   if [[ $p == 0 || ! $p ]]; then
 274     break
 275   fi
 276   my_pids+=($p)
 277 done
 278 ### end get pids that this program depends on so we dont kill them
 279
 280 for vol in ${all_vols[@]}; do
 281   d=/$vol
 282   if ! awk '{print $2}' /etc/fstab | grep -xF $d &>/dev/null; then
 283     continue
 284   fi
 285
 286
 287   ##### begin building up list of bind mounts  ######
 288   binds=() # list of bind mounts
 289   roots=($d)
 290   while true; do
 291     new_roots=()
 292     for r in ${roots[@]}; do
 293       # eg. when r=/q/p, for lines like
 294       # /q/p  /p  none  bind  0 0
 295       # output /p
 296       new_roots+=($(sed -rn "s#^$r/\S+\s+(\S+)\s+none\s+(\S+,|)bind[[:space:],].*#\1#p" /etc/fstab))
 297     done
 298     (( ${#new_roots} )) || break
 299     binds+=(${new_roots[@]})
 300     # roots is used to recursively find binds of binds if they exist.
 301     roots=( ${new_roots[@]} )
 302   done
 303   ##### end building up list of bind mounts  ######
 304
 305
 306   # if latest is already mounted, make sure binds are mounted and move on
 307   m check-subvol-stale $d
 308   # populated by check-subvol-stale if stale
 309   if ! fresh_snap=$(cat /nocow/btrfs-stale/$vol 2>/dev/null); then
 310     mnt $d
 311     did=$(stat -c%d $d)
 312     for b in ${binds[@]}; do
 313       if mountpoint -q $b; then
 314         bid=$(stat -c%d $b)
 315         if [[ $did != $bid ]]; then
 316           umount-kill $b
 317         fi
 318       fi
 319       mnt $b
 320     done
 321     continue
 322   fi
 323
 324   ## not using arbtt at the moment
 325   # if [[ $vol == q ]]; then
 326   #   ## allow to fail, user might not be logged in
 327   #   x sudo -u $(id -nu 1000) XDG_RUNTIME_DIR=/run/user/1000 systemctl --user stop arbtt ||:
 328   # fi
 329   umount_ret=true
 330   unmounted=()
 331   for dir in $(echo $d ${binds[*]}\ |tac -s\ ); do
 332     umount-kill $dir
 333   done
 334
 335   # if we unmounted some but not all, restore them and move on
 336   if ! $umount_ret; then
 337     for dir in ${unmounted[@]}; do
 338       mnt $dir
 339     done
 340     continue
 341   fi
 342
 343   #### begin dealing with leaf vols ####
 344
 345   ### begin getting root_dir
 346   ### this is duplicated in check-subvol-stale
 347
 348   dev=$(sed -rn "s,^\s*([^#]\S*)\s+$d\s.*,\1,p" /etc/fstab /etc/mtab|head -n1)
 349   d dev=$dev
 350   # note, we need $dev because $d might not be mounted, and we do this loop
 351   # because the device in fstab for the rootfs can be different.
 352   for devx in $(btrfs fil show $dev| sed -rn 's#.*path (\S+)$#\1#p'); do
 353     if [[ $devx == dm-* ]]; then
 354       devx=/dev/$devx
 355       mapper-dev devx
 356     fi
 357     d devx=$devx
 358     root_dir=$(sed -rn "s,^\s*$devx\s+(\S+).*\bsubvolid=[05]\b.*,\1,p" /etc/mtab /etc/fstab|head -n1)
 359     if [[ $root_dir ]]; then
 360       d root_dir=$root_dir
 361       break
 362     fi
 363   done
 364   if [[ ! $root_dir ]]; then
 365     echo "$0: error could not find root subvol mount for $dev" >&2
 366     exit 1
 367   fi
 368   ### end getting root_dir
 369
 370   cd $root_dir
 371   if [[ -e $vol ]]; then
 372     leaf=$vol.leaf.$(date +%Y-%m-%dT%H:%M:%S%z)
 373     m mv $vol $leaf
 374     m btrfs property set -ts $leaf ro true
 375
 376     ### begin check if leaf is different, delete it if not ###
 377     if [[ -e /a/opt/btrfs-snapshots-diff/btrfs-snapshots-diff.py ]]; then
 378       source /a/bin/distro-functions/src/package-manager-abstractions
 379       #pi python-jmespath # dependency of btrfs-snapshots-diff
 380       # todo: need python3 port of btrfs-snapshots-diff, py2 no exist on nabia
 381       parentid=$(btrfs sub show $leaf | awk '$1 == "Parent" && $2 == "UUID:" {print $3}')
 382       bsubs=(btrbk/$vol.*)
 383       bsub=
 384       # go in reverse order as its more likely to be at the end
 385       for ((i=${#bsubs[@]}-1; i>=0; i--)); do
 386         if [[ $parentid == $(btrfs sub show ${bsubs[i]} | awk '$1 == "UUID:" {print $2}') ]]; then
 387           bsub=${bsubs[i]}
 388           break
 389         fi
 390       done
 391       if [[ $bsub ]]; then
 392         tmp=$(mktemp)
 393         # in testing, same subvol is 136 bytes. allow some overhead. 32 happens sometimes under systemd.
 394         # $ errno 32
 395         # EPIPE 32 Broken pipe
 396         btrfs send --no-data -p $bsub $leaf | head -c 1000 > $tmp || [[ $? == 141 || ${PIPESTATUS[0]} == 32 ]]
 397         if (( $(stat -c%s $tmp) < 1000)); then
 398           # example output for an empty diff:
 399           # Found a valid Btrfs stream header, version 1
 400           # o.leaf.2019-05-15T14:00:50-0400;snapshot: uuid=ba045ea30737dd449003f1ee40ec12d0, ctrasid=109533, clone_uuid=3c7e3544e486834aa71d89e5b8f30056, clone_ctransid=109533
 401           lines=$(/a/opt/btrfs-snapshots-diff/btrfs-snapshots-diff.py -s -f $tmp | \
 402                     grep -vxF "Found a valid Btrfs stream header, version 1" | \
 403                     grep -cv "^[^;]*;snapshot: ") ||:
 404           if [[ $lines == 0 ]]; then
 405             # rotate in case we find a bug, weve got 2 old ones
 406             tmpleaf=($vol.tmpleaf2.*)
 407             if (( ${#tmpleaf[@]} )); then
 408               x btrfs sub del ${tmpleaf[@]}
 409             fi
 410             tmpleaf=($vol.tmpleaf1.*)
 411             if (( ${#tmpleaf[@]} )); then
 412               x mv ${tmpleaf[0]} $vol.tmpleaf2.${tmpleaf[0]#$vol.tmpleaf1.}
 413             fi
 414             echo suspected identical: $bsub $leaf
 415             x mv $leaf $vol.tmpleaf1.${leaf#$vol.leaf.}
 416           fi
 417         fi
 418       fi
 419     fi
 420     ### end check if leaf is different, delete it if not ###
 421
 422     ## begin expire leaf vols ##
 423     leaf_vols=($vol.leaf.*)
 424     count=${#leaf_vols[@]}
 425     leaf_limit_time=$(( EPOCHSECONDS - 60*60*24*60 )) # 60 days
 426     leaf_new_limit_time=$(( EPOCHSECONDS - 60*60*24 )) # 1 day
 427     # this goes backwards from oldest. leaf_new_limit_time is just in case
 428     # the order gets screwed up or something.
 429     for leaf in ${leaf_vols[@]}; do
 430       leaf_time=$(date -d ${leaf#$vol.leaf.} +%s)
 431       if (( leaf_limit_time > leaf_time || ( leaf_new_limit_time > leaf_time && count > 15 ) )); then
 432         x btrfs sub del $leaf
 433       fi
 434       count=$((count-1))
 435     done
 436     ## end expire leaf vols ##
 437   fi
 438   #### end dealing with leaf vols ####
 439
 440   # Note, we make a few assumptions in this script, like
 441   # $d was not a different subvol id than $vol, and
 442   # things otherwise didn't get mounted very strangely.
 443   m btrfs sub snapshot $fresh_snap $vol
 444   for dir in $d ${binds[@]}; do
 445     m mnt $dir
 446   done
 447
 448   ## arbtt disabled for now
 449   # if [[ $vol == q ]]; then
 450   #   # maybe this will fail if X is not running
 451   #   x sudo -u $(id -nu 1000) XDG_RUNTIME_DIR=/run/user/1000 systemctl --user start arbtt ||:
 452   # fi
 453
 454   stale_dir=/nocow/btrfs-stale
 455   rm -f $stale_dir/$d
 456 done
 457
 458
 459
 460 for dir in /mnt/r7/amy/{root/root,boot/boot}_ubuntubionic /mnt/{root2/root,boot2/boot}_ubuntubionic; do
 461   vol=${dir##*/}
 462   root_dir=${dir%/*}
 463   if [[ ! -d $root_dir ]]; then
 464     # this only exists on host kd currently
 465     continue
 466   fi
 467   # if latest is already mounted, make sure binds are mounted and move on
 468   m check-subvol-stale -p $dir
 469   # populated by check-subvol-stale if stale
 470   if ! fresh_snap=$(cat /nocow/btrfs-stale/$vol 2>/dev/null); then
 471     continue
 472   fi
 473   if [[ -d $dir ]]; then
 474     if ! kill-dir TERM TERM TERM INT INT HUP HUP TERM TERM TERM INT INT HUP HUP; then
 475       if $force; then  kill-dir KILL; fi
 476     fi
 477     m btrfs sub del $dir
 478   fi
 479   m btrfs sub snapshot $fresh_snap $dir
 480   rm -f /nocow/btrfs-stale/$vol
 481 done
 482
 483 exit $ret
 484
 485