A collection of dracut fixes

- In older systems without sysroot.mount, import before dracut-mount,
  and re-enable old dracut mount hook
- rootflags MUST be present even if the administrator neglected to
  specify it explicitly
- Check that mount.zfs exists in sbindir
- Remove awk and head as (now unused) requirements, add grep, and
  install the right mount.zfs
- Eliminate one use of grep in Dracut
- Use a more accurate grepping statement to identify zfsutil in rootflags
- Ensure that pooldev is nonempty
- Properly handle /dev/sd* devices and more
- Use new -P to get list of zpool devices
- Bail out of the generator when zfs:AUTO is on the root command line
- Ignore errors from systemctl trying to load sysroot.mount, we only
  care about the output
- Determine which one is the correct initqueuedir at run time.
- Add a compatibility getargbool for our detection / setup script.
- Update dracut .gitignore files

Signed-off-by: <Matthew Thode mthode@mthode.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4558
Closes #4562

contrib/dracut/02zfsexpandknowledge/.gitignore

@@ -0,0 +1 @@
+module-setup.sh

contrib/dracut/02zfsexpandknowledge/module-setup.sh.in

@@ -15,21 +15,24 @@ get_pool_devices() {
   local poolconfigoutput
   local pooldev
   local prefix
+  local resolved
   poolconfigtemp=`mktemp`
-  @sbindir@/zpool list -v -H "$1" > "$poolconfigtemp" 2>&1
+  @sbindir@/zpool list -v -H -P "$1" > "$poolconfigtemp" 2>&1
   if [ "$?" != "0" ] ; then
     poolconfigoutput=$(cat "$poolconfigtemp")
     dinfo "zfsexpandknowledge: pool $1 cannot be listed: $poolconfigoutput"
   else
     while read pooldev ; do
-      for prefix in /dev/disk/* /dev/mapper ; do
-        if [ -e "$prefix"/"$pooldev" ] ; then
-          dinfo "zfsexpandknowledge: pool $1 has device $prefix/$pooldev"
-          echo `readlink -f "$prefix"/"$pooldev"`
-          break
+        if [ -n "$pooldev" -a -e "$pooldev" ] ; then
+          if [ -h "$pooldev" ] ; then
+              resolved=`readlink -f "$pooldev"`
+          else
+              resolved="$pooldev"
+          fi
+          dinfo "zfsexpandknowledge: pool $1 has device $pooldev (which resolves to $resolved)"
+          echo "$resolved"
         fi
-      done
-    done < <(cat "$poolconfigtemp" | awk -F '\t' 'NR>1 { print $2 }')
+    done < <(cat "$poolconfigtemp" |  awk -F '\t' '/\t\/dev/ { print $2 }')
   fi
   rm -f "$poolconfigtemp"
 }

contrib/dracut/90zfs/.gitignore

@@ -2,4 +2,5 @@ export-zfs.sh
 module-setup.sh
 mount-zfs.sh
 parse-zfs.sh
+zfs-generator.sh
 zfs-lib.sh

contrib/dracut/90zfs/module-setup.sh.in

@@ -5,8 +5,11 @@ check() {
 	[ "${1}" = "-d" ] && return 0
 
 	# Verify the zfs tool chain
-	which zpool >/dev/null 2>&1 || return 1
-	which zfs >/dev/null 2>&1 || return 1
+	for tool in "@sbindir@/zpool" "@sbindir@/zfs" "@sbindir@/mount.zfs" ; do
+		test -x "$tool" || return 1
+	done
+	# Verify grep exists
+	which grep >/dev/null 2>&1 || return 1
 
 	return 0
 }
@@ -31,20 +34,18 @@ install() {
 	inst_rules @udevruledir@/90-zfs.rules
 	inst_rules @udevruledir@/69-vdev.rules
 	inst_rules @udevruledir@/60-zvol.rules
+	dracut_install hostid
+	dracut_install grep
 	dracut_install @sbindir@/zfs
 	dracut_install @sbindir@/zpool
+	dracut_install @sbindir@/mount.zfs
 	dracut_install @udevdir@/vdev_id
 	dracut_install @udevdir@/zvol_id
-	dracut_install mount.zfs
-	dracut_install hostid
-	dracut_install awk
-	dracut_install head
 	inst_hook cmdline 95 "${moddir}/parse-zfs.sh"
 	if [ -n "$systemdutildir" ] ; then
 		inst_script "${moddir}/zfs-generator.sh" "$systemdutildir"/system-generators/dracut-zfs-generator
-	else
-		inst_hook mount 98 "${moddir}/mount-zfs.sh"
 	fi
+	inst_hook mount 98 "${moddir}/mount-zfs.sh"
 	inst_hook shutdown 30 "${moddir}/export-zfs.sh"
 
 	inst_simple "${moddir}/zfs-lib.sh" "/lib/dracut-zfs-lib.sh"

contrib/dracut/90zfs/mount-zfs.sh.in

@@ -10,6 +10,16 @@ case "${root}" in
 	*) return ;;
 esac
 
+# If sysroot.mount exists, the initial RAM disk configured
+# it to mount ZFS on root.  In that case, we bail early.
+loadstate="$(systemctl --system --show -p LoadState sysroot.mount || true)"
+if [ "${loadstate}" = "LoadState=not-found" -o "${loadstate}" = "" ] ; then
+	info "ZFS: sysroot.mount absent, mounting root with mount-zfs.sh"
+else
+	info "ZFS: sysroot.mount present, delegating root mount to it"
+	return
+fi
+
 # Delay until all required block devices are present.
 udevadm settle
 

contrib/dracut/90zfs/parse-zfs.sh.in

@@ -55,5 +55,9 @@ esac
 # modules to settle before mounting.
 if [ ${wait_for_zfs} -eq 1 ]; then
 	ln -s /dev/null /dev/root 2>/dev/null
-	echo '[ -e /dev/zfs ]' > "${hookdir}/initqueue/finished/zfs.sh"
+	initqueuedir="${hookdir}/initqueue/finished"
+	test -d initqueuedir || {
+		initqueuedir="${hookdir}/initqueue-finished"
+	}
+	echo '[ -e /dev/zfs ]' > "${initqueuedir}/zfs.sh"
 fi

contrib/dracut/90zfs/zfs-generator.sh.in

@@ -13,10 +13,18 @@ type getarg >/dev/null 2>&1 || . "$dracutlib"
 [ -z "$rootflags" ]  && rootflags=$(getarg rootflags=)
 
 [ "${root##zfs:}" = "${root}" -a "${root##ZFS=}" = "${root}" -a "$rootfstype" != "zfs" ] && exit 0
+# If root is set to zfs:AUTO, then we know sysroot.mount will not be generated
+# so we have no need to enhance it.
+# See https://github.com/zfsonlinux/zfs/pull/4558#discussion_r61118952 for details.
+if [ "${root}" = "zfs:AUTO" ] ; then
+  exit 0
+fi
 
 rootfstype=zfs
-if echo "${rootflags}" | grep -q zfsutil ; then
+if echo "${rootflags}" | grep -Eq '^zfsutil$|^zfsutil,|,zfsutil$|,zfsutil,' ; then
     true
+elif test -n "${rootflags}" ; then
+    rootflags="zfsutil,${rootflags}"
 else
     rootflags=zfsutil
 fi

contrib/dracut/90zfs/zfs-lib.sh.in

@@ -1,6 +1,24 @@
 #!/bin/sh
 
 command -v getarg >/dev/null || . /lib/dracut-lib.sh
+command -v getargbool >/dev/null || {
+    # Compatibility with older Dracut versions.
+    # With apologies to the Dracut developers.
+    getargbool() {
+        local _b
+        unset _b
+        local _default
+        _default="$1"; shift
+        _b=$(getarg "$@")
+        [ $? -ne 0 -a -z "$_b" ] && _b="$_default"
+        if [ -n "$_b" ]; then
+            [ $_b = "0" ] && return 1
+            [ $_b = "no" ] && return 1
+            [ $_b = "off" ] && return 1
+        fi
+        return 0
+    }
+}
 
 OLDIFS="${IFS}"
 NEWLINE="

etc/systemd/system/zfs-import-cache.service.in

@@ -4,6 +4,7 @@ DefaultDependencies=no
 Requires=systemd-udev-settle.service
 After=systemd-udev-settle.service
 After=cryptsetup.target
+Before=dracut-mount.service
 ConditionPathExists=@sysconfdir@/zfs/zpool.cache
 
 [Service]

etc/systemd/system/zfs-import-scan.service.in

@@ -4,6 +4,7 @@ DefaultDependencies=no
 Requires=systemd-udev-settle.service
 After=systemd-udev-settle.service
 After=cryptsetup.target
+Before=dracut-mount.service
 ConditionPathExists=!@sysconfdir@/zfs/zpool.cache
 
 [Service]