[src/trunk]: src/etc Add mount_critical_filesystems_zfs

[alnsn <alnsn%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/921bffd0d43c
branches:  trunk
changeset: 359966:921bffd0d43c
user:      alnsn <alnsn%NetBSD.org@localhost>
date:      Thu Feb 03 20:52:44 2022 +0000

description:
Add mount_critical_filesystems_zfs

The new function is similar to mount_critical_filesystems
but it walks through ZFS datasets and mounts matching entries.

diffstat:

 etc/rc.subr |  75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 74 insertions(+), 1 deletions(-)

diffs (89 lines):

diff -r 44e28095b42b -r 921bffd0d43c etc/rc.subr
--- a/etc/rc.subr       Thu Feb 03 20:32:38 2022 +0000
+++ b/etc/rc.subr       Thu Feb 03 20:52:44 2022 +0000
@@ -1,4 +1,4 @@
-# $NetBSD: rc.subr,v 1.107 2021/11/06 23:11:43 christos Exp $
+# $NetBSD: rc.subr,v 1.108 2022/02/03 20:52:44 alnsn Exp $
 #
 # Copyright (c) 1997-2011 The NetBSD Foundation, Inc.
 # All rights reserved.
@@ -202,6 +202,79 @@
 }
 
 #
+# mount_critical_filesystems_zfs
+#      Go through the list of critical ZFS mountpoints as provided in
+#      the rc.conf(5) variable $critical_filesystems_zfs, checking
+#      each one to see if it is mounted, and if it is not, mounting it.
+#      It's not an error if file systems prefixed with "OPTIONAL:"
+#      aren't zfs mountpoints.
+mount_critical_filesystems_zfs()
+{
+       eval _fslist=\$critical_filesystems_zfs
+       _tab="  "
+       _mountcrit_es=0
+       for _fs in $_fslist; do
+               _optional=false
+               case "$_fs" in
+               OPTIONAL:*)
+                       _optional=true
+                       _fs="${_fs#*:}"
+                       ;;
+               esac
+
+               _dataset=`
+                       zfs list -H -o mountpoint,name |
+                       while read _line ; do
+                               _dataset=''
+                               case "$_line" in
+                               "${_fs}${_tab}"*)
+                                       _dataset="${_line#*${_tab}}"
+                                       ;;
+                               esac
+                               if [ -n "$_dataset" ]; then
+                                       case "$( zfs get -H -o value canmount $_dataset )" in
+                                       on)
+                                               echo -n "$_dataset"
+                                               break ;;
+                                       *) # noauto|off - dataset isn't supposed to be mounted
+                                               ;;
+                                       esac
+                               fi
+                       done`
+
+               if [ -z "$_dataset" ]; then
+                       if $_optional; then
+                               # ignore this error
+                               print_rc_metadata \
+                               "note:Optional file system $_fs is not present"
+                       else
+                               printf >&2 "%s\n" "No suitable ZFS dataset found for mountpoint $_fs"
+                               _mountcrit_es=1
+                       fi
+               else
+                       _mount_es=
+                       case "$( zfs get -H -o value mounted $_dataset )" in
+                       yes)
+                               _mount_es=1
+                               print_rc_metadata \
+                               "note:File system $_fs was already mounted"
+                               ;;
+                       esac
+
+                       if [ -z "$_mount_es" ]; then
+                               zfs mount "$_dataset" >/dev/null
+                               _mount_es=$?
+                       fi
+
+                       if [ -n "$_mount_es" ]; then
+                               _mountcrit_es="$_mount_es"
+                       fi
+               fi
+       done
+       return $_mountcrit_es
+}
+
+#
 # check_pidfile pidfile procname [interpreter]
 #      Parses the first line of pidfile for a PID, and ensures
 #      that the process is running and matches procname.