dracut fixes for a fragmented essential hierarchy, mostly

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

@@ -100,7 +100,7 @@ if [[ $hostonly ]]; then
         mountpoint "$mp" >/dev/null 2>&1 || continue
         blockdevs=$(find_zfs_block_devices "$mp")
         if [ -z "$blockdevs" ] ; then continue ; fi
-        dinfo "zfsexpandknowledge: block devices backing ZFS dataset $mp: $blockdevs"
+        dinfo "zfsexpandknowledge: block devices backing ZFS dataset $mp: ${blockdevs//$'\n'/ }"
         for dev in $blockdevs
         do
             array_contains "$dev" "${host_devs[@]}" || host_devs+=("$dev")
@@ -114,7 +114,7 @@ if [[ $hostonly ]]; then
                     _depdevname=$(udevadm info --query=property --name="$_depdev" | grep "^DEVNAME=" | sed 's|^DEVNAME=||')
                     _depdevtype=$(get_devtype "$_depdevname")
                     _depmajmin=$(get_maj_min "$_depdevname")
-                    dinfo "zfsexpandknowledge: underlying block device backing ZFS dataset $mp: $_depdevname"
+                    dinfo "zfsexpandknowledge: underlying block device backing ZFS dataset $mp: ${_depdevname//$'\n'/ }"
                     array_contains "$_depdevname" "${host_devs[@]}" || host_devs+=("$_depdevname")
                     host_fs_types["$_depdevname"]="$_depdevtype"
                 done

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

@@ -1,6 +1,7 @@
 #!/bin/sh
 
-echo "zfs-generator: starting" >> /dev/kmsg
+grep -wq debug /proc/cmdline && debug=1
+[ -n "$debug" ] && echo "zfs-generator: starting" >> /dev/kmsg
 
 GENERATOR_DIR="$1"
 [ -n "$GENERATOR_DIR" ] || {
@@ -10,12 +11,13 @@ GENERATOR_DIR="$1"
 
 [ -f /lib/dracut-lib.sh ] && dracutlib=/lib/dracut-lib.sh
 [ -f /usr/lib/dracut/modules.d/99base/dracut-lib.sh ] && dracutlib=/usr/lib/dracut/modules.d/99base/dracut-lib.sh
-
 command -v getarg >/dev/null 2>&1 || {
-    echo "zfs-generator: loading Dracut library from $dracutlib" >> /dev/kmsg
+    [ -n "$debug" ] && echo "zfs-generator: loading Dracut library from $dracutlib" >> /dev/kmsg
     . "$dracutlib"
 }
 
+. /lib/dracut-zfs-lib.sh
+
 [ -z "$root" ]       && root=$(getarg root=)
 [ -z "$rootfstype" ] && rootfstype=$(getarg rootfstype=)
 [ -z "$rootflags" ]  && rootflags=$(getarg rootflags=)
@@ -27,44 +29,90 @@ command -v getarg >/dev/null 2>&1 || {
 	[ "$rootfstype" != "zfs" ] &&
 	exit 0
 
-rootfstype=zfs
 case ",${rootflags}," in
 	*,zfsutil,*) ;;
 	,,)	rootflags=zfsutil ;;
 	*)	rootflags="zfsutil,${rootflags}" ;;
 esac
 
-echo "zfs-generator: writing extension for sysroot.mount to $GENERATOR_DIR"/sysroot.mount.d/zfs-enhancement.conf >> /dev/kmsg
+if [ "${root}" != "zfs:AUTO" ]; then
+  root="${root##zfs:}"
+  root="${root##ZFS=}"
+fi
 
-[ -d "$GENERATOR_DIR" ] || mkdir "$GENERATOR_DIR"
-[ -d "$GENERATOR_DIR"/sysroot.mount.d ] || mkdir "$GENERATOR_DIR"/sysroot.mount.d
+[ -n "$debug" ] && echo "zfs-generator: writing extension for sysroot.mount to $GENERATOR_DIR/sysroot.mount.d/zfs-enhancement.conf" >> /dev/kmsg
 
+
+mkdir -p "$GENERATOR_DIR"/sysroot.mount.d "$GENERATOR_DIR"/initrd-root-fs.target.requires "$GENERATOR_DIR"/dracut-pre-mount.service.d
 {
     echo "[Unit]"
     echo "Before=initrd-root-fs.target"
     echo "After=zfs-import.target"
+    echo
     echo "[Mount]"
-    if [ "${root}" = "zfs:AUTO" ] ; then
+    if [ "${root}" = "zfs:AUTO" ]; then
       echo "PassEnvironment=BOOTFS"
       echo 'What=${BOOTFS}'
     else
-      root="${root##zfs:}"
-      root="${root##ZFS=}"
       echo "What=${root}"
     fi
-    echo "Type=${rootfstype}"
+    echo "Type=zfs"
     echo "Options=${rootflags}"
 } > "$GENERATOR_DIR"/sysroot.mount.d/zfs-enhancement.conf
+ln -fs ../sysroot.mount "$GENERATOR_DIR"/initrd-root-fs.target.requires/sysroot.mount
 
-[ -d "$GENERATOR_DIR"/initrd-root-fs.target.requires ] || mkdir -p "$GENERATOR_DIR"/initrd-root-fs.target.requires
-ln -s ../sysroot.mount "$GENERATOR_DIR"/initrd-root-fs.target.requires/sysroot.mount
 
+if [ "${root}" = "zfs:AUTO" ]; then
+  {
+      echo "[Unit]"
+      echo "Before=initrd-root-fs.target"
+      echo "After=sysroot.mount"
+      echo "DefaultDependencies=no"
+      echo
+      echo "[Service]"
+      echo "Type=oneshot"
+      echo "PassEnvironment=BOOTFS"
+      echo "ExecStart=/bin/sh -c '" '                                        \
+        . /lib/dracut-zfs-lib.sh;                                            \
+        _zfs_nonroot_necessities_cb() {                                      \
+            zfs mount | grep -m1 -q "^$1 " && return 0;                      \
+            echo "Mounting $1 on /sysroot$2";                                \
+            mount -o zfsutil -t zfs "$1" "/sysroot$2";                       \
+        };                                                                   \
+        for_relevant_root_children "${BOOTFS}" _zfs_nonroot_necessities_cb;' \
+      "'"
+  } > "$GENERATOR_DIR"/zfs-nonroot-necessities.service
+  ln -fs ../zfs-nonroot-necessities.service "$GENERATOR_DIR"/initrd-root-fs.target.requires/zfs-nonroot-necessities.service
+else
+  # We can solve this statically at generation time, so do!
+  _zfs_generator_cb() {
+      dset="${1}"
+      mpnt="${2}"
+      unit="sysroot$(echo "$mpnt" | sed 's;/;-;g').mount"
+
+      {
+          echo "[Unit]"
+          echo "Before=initrd-root-fs.target"
+          echo "After=sysroot.mount"
+          echo
+          echo "[Mount]"
+          echo "Where=/sysroot${mpnt}"
+          echo "What=${dset}"
+          echo "Type=zfs"
+          echo "Options=zfsutil"
+      } > "$GENERATOR_DIR/${unit}"
+      ln -fs ../"${unit}" "$GENERATOR_DIR"/initrd-root-fs.target.requires/"${unit}"
+  }
+
+  for_relevant_root_children "${root}" _zfs_generator_cb
+fi
 
-[ -d "$GENERATOR_DIR"/dracut-pre-mount.service.d ] || mkdir "$GENERATOR_DIR"/dracut-pre-mount.service.d
 
 {
     echo "[Unit]"
     echo "After=zfs-import.target"
 } > "$GENERATOR_DIR"/dracut-pre-mount.service.d/zfs-enhancement.conf
 
-echo "zfs-generator: finished" >> /dev/kmsg
+[ -n "$debug" ] && echo "zfs-generator: finished" >> /dev/kmsg
+
+exit 0

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

@@ -23,6 +23,7 @@ command -v getargbool >/dev/null || {
 OLDIFS="${IFS}"
 NEWLINE="
 "
+TAB="	"
 
 ZPOOL_IMPORT_OPTS=""
 if getargbool 0 zfs_force -y zfs.force -y zfsforce ; then
@@ -58,7 +59,7 @@ find_bootfs() {
 # import_pool POOL
 #   imports the given zfs pool if it isn't imported already.
 import_pool() {
-        pool="${1}"
+    pool="${1}"
 
     if ! zpool list -H "${pool}" > /dev/null 2>&1; then
         info "ZFS: Importing pool ${pool}..."
@@ -71,26 +72,62 @@ import_pool() {
     return 0
 }
 
+_mount_dataset_cb() {
+    mount -o zfsutil -t zfs "${1}" "${NEWROOT}${2}"
+}
+
 # mount_dataset DATASET
 #   mounts the given zfs dataset.
 mount_dataset() {
-        dataset="${1}"
+    dataset="${1}"
     mountpoint="$(zfs get -H -o value mountpoint "${dataset}")"
+    ret=0
 
     # We need zfsutil for non-legacy mounts and not for legacy mounts.
     if [ "${mountpoint}" = "legacy" ] ; then
-        mount -t zfs "${dataset}" "${NEWROOT}"
+        mount -t zfs "${dataset}" "${NEWROOT}" || ret=$?
     else
-        mount -o zfsutil -t zfs "${dataset}" "${NEWROOT}"
+        mount -o zfsutil -t zfs "${dataset}" "${NEWROOT}" || ret=$?
+
+        if [ "$ret" = "0" ]; then
+            for_relevant_root_children "${dataset}" _mount_dataset_cb || ret=$?
+        fi
     fi
 
-    return $?
+    return ${ret}
+}
+
+# for_relevant_root_children DATASET EXEC
+#   Runs "EXEC dataset mountpoint" for all children of DATASET that are needed for system bringup
+#   Used by zfs-generator.sh and friends, too!
+for_relevant_root_children() {
+    dataset="${1}"
+    exec="${2}"
+
+    zfs list -t filesystem -Ho name,mountpoint,canmount -r "${dataset}" |
+        (
+            _ret=0
+            while IFS="${TAB}" read -r dataset mountpoint canmount; do
+                [ "$canmount" != "on" ] && continue
+
+                case "$mountpoint" in
+                    /etc|/bin|/lib|/lib??|/libx32|/usr)
+                        # If these aren't mounted we may not be able to get to the real init at all, or pollute the dataset holding the rootfs
+                        "${exec}" "${dataset}" "${mountpoint}" || _ret=$?
+                        ;;
+                    *)
+                        # Up to the real init to remount everything else it might need
+                        ;;
+                esac
+            done
+            exit ${_ret}
+        )
 }
 
 # export_all OPTS
 #   exports all imported zfs pools.
 export_all() {
-        opts="${@}"
+    opts="${@}"
     ret=0
 
     IFS="${NEWLINE}"

contrib/dracut/90zfs/zfs-rollback-bootfs.service.in

@@ -10,5 +10,5 @@ ConditionKernelCommandLine=bootfs.rollback
 # ${BOOTFS} should have been set by zfs-env-bootfs.service
 Type=oneshot
 ExecStartPre=/bin/sh -c 'test -n "${BOOTFS}"'
-ExecStart=/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.rollback)"; /sbin/zfs rollback -Rf "${BOOTFS}@${SNAPNAME:-%v}"'
+ExecStart=/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.rollback)"; @sbindir@/zfs rollback -Rf "${BOOTFS}@${SNAPNAME:-%v}"'
 RemainAfterExit=yes

contrib/dracut/90zfs/zfs-snapshot-bootfs.service.in

@@ -10,5 +10,5 @@ ConditionKernelCommandLine=bootfs.snapshot
 # ${BOOTFS} should have been set by zfs-env-bootfs.service
 Type=oneshot
 ExecStartPre=/bin/sh -c 'test -n "${BOOTFS}"'
-ExecStart=-/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.snapshot)"; /sbin/zfs snapshot "${BOOTFS}@${SNAPNAME:-%v}"'
+ExecStart=-/bin/sh -c '. /lib/dracut-lib.sh; SNAPNAME="$(getarg bootfs.snapshot)"; @sbindir@/zfs snapshot "${BOOTFS}@${SNAPNAME:-%v}"'
 RemainAfterExit=yes

contrib/initramfs/scripts/zfs

@@ -935,9 +935,14 @@ mountroot()
 
 	# Go through the complete list (recursively) of all filesystems below
 	# the real root dataset
-	filesystems=$("${ZFS}" list -oname -tfilesystem -H -r "${ZFS_BOOTFS}")
-	for fs in $filesystems $ZFS_INITRD_ADDITIONAL_DATASETS
-	do
+	filesystems="$("${ZFS}" list -oname -tfilesystem -H -r "${ZFS_BOOTFS}")"
+	OLD_IFS="$IFS" ; IFS="
+"
+	for fs in $filesystems; do
+		IFS="$OLD_IFS" mount_fs "$fs"
+	done
+	IFS="$OLD_IFS"
+	for fs in $ZFS_INITRD_ADDITIONAL_DATASETS; do
 		mount_fs "$fs"
 	done