Fix edge cases

If zpool is set to a non-existent pool on the kernel command line, we
incorrectly handle setting a kernel mask in select_kernel.

This also simplifies setting BOOTFS, so we should now always have it
correctly set, or empty.

Add the 'ip' tool, so you can set an IP and zfs send/recv in the
bootloader.

90zfsbootmenu/module-setup.sh

@@ -74,6 +74,7 @@ install() {
   dracut_install tput
   dracut_install mount
   dracut_install df
+  dracut_install ip
   dracut_install /usr/bin/timeout
   dracut_install /usr/bin/mkdir
   dracut_install /usr/bin/tail

90zfsbootmenu/zfsbootmenu-lib.sh

@@ -150,10 +150,6 @@ kexec_kernel() {
 
   umount_zfs ${fs}
 
-  if ! [ $? -eq 0 ]; then
-    emergency_shell "unable to export pools"
-  fi
-
   kexec -e -i
 }
 
@@ -239,13 +235,14 @@ find_be_kernels() {
 # returns: nothing
 
 select_kernel() {
-  local fs
-  fs="${1}"
+  local zfsbe
+  zfsbe="${1}"
 
   local sane specific_kernel kexec_args
-  sane="$( underscore ${fs} )"
+  sane="$( underscore ${zfsbe} )"
 
-  specific_kernel="$( zfs get -H -o value org.zfsbootmenu:kernel ${BOOTFS} )"
+  specific_kernel="$( zfs get -H -o value org.zfsbootmenu:kernel ${zfsbe} )"
+
   # No value set, pick the last kernel entry
   if [ "${specific_kernel}" = "-" ]; then
     kexec_args="$( tail -1 ${BASE}/${sane} )"

90zfsbootmenu/zfsbootmenu.sh

@@ -56,14 +56,14 @@ fi
 
 # Attempt to find the bootfs property 
 datasets="$( zpool list -H -o bootfs ${pool} )"
-if [ "$datasets" = "-" ]; then
-  BOOTFS=
-else
-  while read -r line; do
+while read -r line; do
+  if [ "${line}" = "-" ]; then
+    BOOTFS=
+  else
     BOOTFS="${line}"
     break
-  done <<<"${datasets}"
-fi
+  fi
+done <<<"${datasets}"
 
 # If BOOTFS is not empty display the fast boot menu
 fast_boot=0