1 files changed, 137 insertions, 0 deletions
diff --git a/modules.d/95nbd/nbdroot.sh b/modules.d/95nbd/nbdroot.sh
new file mode 100755
index 0000000..b1a8030
--- /dev/null
+++ b/modules.d/95nbd/nbdroot.sh
@@ -0,0 +1,137 @@
+#!/bin/sh
+
+type getarg > /dev/null 2>&1 || . /lib/dracut-lib.sh
+
+PATH=/usr/sbin:/usr/bin:/sbin:/bin
+
+# Huh? Empty $1?
+[ -z "$1" ] && exit 1
+
+# Huh? Empty $2?
+[ -z "$2" ] && exit 1
+
+# Huh? Empty $3?
+[ -z "$3" ] && exit 1
+
+# root is in the form root=nbd:srv:port[:fstype[:rootflags[:nbdopts]]]
+# shellcheck disable=SC2034
+netif="$1"
+nroot="$2"
+NEWROOT="$3"
+
+# If it's not nbd we don't continue
+[ "${nroot%%:*}" = "nbd" ] || return
+
+nroot=${nroot#nbd:}
+nbdserver=${nroot%%:*}
+if [ "${nbdserver%"${nbdserver#?}"}" = "[" ]; then
+    nbdserver=${nroot#[}
+    nbdserver=${nbdserver%%]:*}
+    nroot=${nroot#*]:}
+else
+    nroot=${nroot#*:}
+fi
+nbdport=${nroot%%:*}
+nroot=${nroot#*:}
+nbdfstype=${nroot%%:*}
+nroot=${nroot#*:}
+nbdflags=${nroot%%:*}
+nbdopts=${nroot#*:}
+
+if [ "$nbdopts" = "$nbdflags" ]; then
+    unset nbdopts
+fi
+if [ "$nbdflags" = "$nbdfstype" ]; then
+    unset nbdflags
+fi
+if [ "$nbdfstype" = "$nbdport" ]; then
+    unset nbdfstype
+fi
+if [ -z "$nbdfstype" ]; then
+    nbdfstype=auto
+fi
+
+# look through the NBD options and pull out the ones that need to
+# go before the host etc. Append a ',' so we know we terminate the loop
+nbdopts=${nbdopts},
+while [ -n "$nbdopts" ]; do
+    f=${nbdopts%%,*}
+    nbdopts=${nbdopts#*,}
+    if [ -z "$f" ]; then
+        break
+    fi
+    if [ -z "${f%bs=*}" -o -z "${f%timeout=*}" ]; then
+        preopts="$preopts $f"
+        continue
+    fi
+    opts="$opts $f"
+done
+
+# look through the flags and see if any are overridden by the command line
+nbdflags=${nbdflags},
+while [ -n "$nbdflags" ]; do
+    f=${nbdflags%%,*}
+    nbdflags=${nbdflags#*,}
+    if [ -z "$f" ]; then
+        break
+    fi
+    if [ "$f" = "ro" -o "$f" = "rw" ]; then
+        nbdrw=$f
+        continue
+    fi
+    fsopts=${fsopts:+$fsopts,}$f
+done
+
+getarg ro && nbdrw=ro
+getarg rw && nbdrw=rw
+fsopts=${fsopts:+$fsopts,}${nbdrw}
+
+# XXX better way to wait for the device to be made?
+i=0
+while [ ! -b /dev/nbd0 ]; do
+    [ $i -ge 20 ] && exit 1
+    udevadm settle --exit-if-exists=/dev/nbd0
+    i=$((i + 1))
+done
+
+# If we didn't get a root= on the command line, then we need to
+# add the udev rules for mounting the nbd0 device
+if [ "$root" = "block:/dev/root" -o "$root" = "dhcp" ]; then
+    printf 'KERNEL=="nbd0", ENV{DEVTYPE}!="partition", ENV{ID_FS_TYPE}=="?*", SYMLINK+="root"\n' > /etc/udev/rules.d/99-nbd-root.rules
+    udevadm control --reload
+    wait_for_dev -n /dev/root
+
+    if [ -z "$DRACUT_SYSTEMD" ]; then
+        type write_fs_tab > /dev/null 2>&1 || . /lib/fs-lib.sh
+
+        write_fs_tab /dev/root "$nbdfstype" "$fsopts"
+
+        printf '/bin/mount %s\n' \
+            "$NEWROOT" \
+            > "$hookdir"/mount/01-$$-nbd.sh
+    else
+        mkdir -p /run/systemd/system/sysroot.mount.d
+        cat << EOF > /run/systemd/system/sysroot.mount.d/dhcp.conf
+[Mount]
+Where=/sysroot
+What=/dev/root
+Type=$nbdfstype
+Options=$fsopts
+EOF
+        systemctl --no-block daemon-reload
+    fi
+    # if we're on systemd, use the nbd-generator script
+    # to create the /sysroot mount.
+fi
+
+if ! [ "$nbdport" -gt 0 ] 2> /dev/null; then
+    nbdport="-name $nbdport"
+fi
+
+if ! nbd-client -check /dev/nbd0 > /dev/null; then
+    # shellcheck disable=SC2086
+    nbd-client -p -systemd-mark "$nbdserver" $nbdport /dev/nbd0 $opts || exit 1
+fi
+
+need_shutdown
+exit 0