From 7de48355c3f9494c2394aefa5e5ad88f53ea06ef Mon Sep 17 00:00:00 2001
From: Peter Jones <pjones@redhat.com>
Date: Fri, 9 Dec 2016 15:40:29 -0500
Subject: [PATCH] Add BLS support to grub-mkconfig

GRUB now has BootLoaderSpec support, the user can choose to use this by
setting GRUB_ENABLE_BLSCFG to true in /etc/default/grub. On this setup,
the boot menu entries are not added to the grub.cfg, instead BLS config
files are parsed by blscfg command and the entries created dynamically.
---
 util/grub-mkconfig.in     |  3 ++-
 util/grub-mkconfig_lib.in | 29 +++++++++++++++++++----------
 util/grub.d/10_linux.in   | 37 ++++++++++++++++++++++++++++++++++++-
 3 files changed, 57 insertions(+), 12 deletions(-)

diff --git a/util/grub-mkconfig.in b/util/grub-mkconfig.in
index 4248b9341ab..c20171919d9 100644
--- a/util/grub-mkconfig.in
+++ b/util/grub-mkconfig.in
@@ -259,7 +259,8 @@ export GRUB_DEFAULT \
   GRUB_OS_PROBER_SKIP_LIST \
   GRUB_DISABLE_SUBMENU \
   GRUB_DEFAULT_DTB \
-  SUSE_BTRFS_SNAPSHOT_BOOTING
+  SUSE_BTRFS_SNAPSHOT_BOOTING \
+  GRUB_ENABLE_BLSCFG
 
 if test "x${grub_cfg}" != "x"; then
   rm -f "${grub_cfg}.new"
diff --git a/util/grub-mkconfig_lib.in b/util/grub-mkconfig_lib.in
index b3aae534ddc..1acc1d01c39 100644
--- a/util/grub-mkconfig_lib.in
+++ b/util/grub-mkconfig_lib.in
@@ -30,6 +30,9 @@ fi
 if test "x$grub_file" = x; then
   grub_file="${bindir}/@grub_file@"
 fi
+if test "x$grub_editenv" = x; then
+  grub_editenv="${bindir}/@grub_editenv@"
+fi
 if test "x$grub_mkrelpath" = x; then
   grub_mkrelpath="${bindir}/@grub_mkrelpath@"
 fi
@@ -127,10 +130,16 @@ EOF
 
 prepare_grub_to_access_device ()
 {
+  local device=$1 && shift
+  if [ "$#" -gt 0 ]; then
+    local variable=$1 && shift
+  else
+    local variable=root
+  fi
   old_ifs="$IFS"
   IFS='
 '
-  partmap="`"${grub_probe}" --device $@ --target=partmap`"
+  partmap="`"${grub_probe}" --device ${device} --target=partmap`"
   for module in ${partmap} ; do
     case "${module}" in
       netbsd | openbsd)
@@ -141,34 +150,34 @@ prepare_grub_to_access_device ()
   done
 
   # Abstraction modules aren't auto-loaded.
-  abstraction="`"${grub_probe}" --device $@ --target=abstraction`"
+  abstraction="`"${grub_probe}" --device ${device} --target=abstraction`"
   for module in ${abstraction} ; do
     echo "insmod ${module}"
   done
 
-  fs="`"${grub_probe}" --device $@ --target=fs`"
+  fs="`"${grub_probe}" --device ${device} --target=fs`"
   for module in ${fs} ; do
     echo "insmod ${module}"
   done
 
   if [ x$GRUB_ENABLE_CRYPTODISK = xy ]; then
-      for uuid in `"${grub_probe}" --device $@ --target=cryptodisk_uuid`; do
+      for uuid in `"${grub_probe}" --device ${device} --target=cryptodisk_uuid`; do
 	  echo "cryptomount -u $uuid"
       done
   fi
 
   # If there's a filesystem UUID that GRUB is capable of identifying, use it;
   # otherwise set root as per value in device.map.
-  fs_hint="`"${grub_probe}" --device $@ --target=compatibility_hint`"
+  fs_hint="`"${grub_probe}" --device ${device} --target=compatibility_hint`"
   if [ "x$fs_hint" != x ]; then
-    echo "set root='$fs_hint'"
+    echo "set ${variable}='$fs_hint'"
   fi
-  if [ "x$GRUB_DISABLE_UUID" != "xtrue" ] && fs_uuid="`"${grub_probe}" --device $@ --target=fs_uuid 2> /dev/null`" ; then
-    hints="`"${grub_probe}" --device $@ --target=hints_string 2> /dev/null`" || hints=
+  if [ "x$GRUB_DISABLE_UUID" != "xtrue" ] && fs_uuid="`"${grub_probe}" --device ${device} --target=fs_uuid 2> /dev/null`" ; then
+    hints="`"${grub_probe}" --device ${device} --target=hints_string 2> /dev/null`" || hints=
     echo "if [ x\$feature_platform_search_hint = xy ]; then"
-    echo "  search --no-floppy --fs-uuid --set=root ${hints} ${fs_uuid}"
+    echo "  search --no-floppy --fs-uuid --set=${variable} ${hints} ${fs_uuid}"
     echo "else"
-    echo "  search --no-floppy --fs-uuid --set=root ${fs_uuid}"
+    echo "  search --no-floppy --fs-uuid --set=${variable} ${fs_uuid}"
     echo "fi"
   fi
   IFS="$old_ifs"
diff --git a/util/grub.d/10_linux.in b/util/grub.d/10_linux.in
index 69415af69b2..aec1ca3eba0 100644
--- a/util/grub.d/10_linux.in
+++ b/util/grub.d/10_linux.in
@@ -135,6 +135,34 @@ linux_entry ()
   if [ -z "$boot_device_id" ]; then
       boot_device_id="$(grub_get_device_id "${GRUB_DEVICE}")"
   fi
+
+  if [ "x${GRUB_ENABLE_BLSCFG}" = "xtrue" ]; then
+    if [ x$dirname = x/ ]; then
+      if [ -z "${prepare_root_cache}" ]; then
+        prepare_grub_to_access_device ${GRUB_DEVICE}
+      fi
+    else
+      if [ -z "${prepare_boot_cache}" ]; then
+        prepare_grub_to_access_device ${GRUB_DEVICE_BOOT}
+      fi
+    fi
+
+    bootefi_device="`${grub_probe} --target=device /boot/efi/`"
+    prepare_grub_to_access_device ${bootefi_device} boot
+
+    cat << EOF
+insmod blscfg
+blscfg
+if [ -s \$prefix/grubenv ]; then
+  load_env
+fi
+EOF
+
+    ${grub_editenv} - set kernelopts="root=${linux_root_device_thisversion} ro ${args}"
+
+    exit 0
+  fi
+
   if [ x$type != xsimple ] ; then
       title=$(mktitle "$type" "$version")
       if [ x"$title" = x"$GRUB_ACTUAL_DEFAULT" ] || [ x"Previous Linux versions>$title" = x"$GRUB_ACTUAL_DEFAULT" ]; then
@@ -239,7 +267,10 @@ submenu_indentation=""
 is_top_level=true
 while [ "x$list" != "x" ] ; do
   linux=`version_find_latest $list`
-  gettext_printf "Found linux image: %s\n" "$linux" >&2
+  if [ "x${GRUB_ENABLE_BLSCFG}" != "xtrue" ]; then
+    gettext_printf "Found linux image: %s\n" "$linux" >&2
+  fi
+
   basename=`basename $linux`
   dirname=`dirname $linux`
   rel_dirname=`make_system_path_relative_to_its_root $dirname`
@@ -303,6 +334,10 @@ while [ "x$list" != "x" ] ; do
   fi
 
   if test -z "${initramfs}" && test -z "${initrd_real}" ; then
+    if [ "x${GRUB_ENABLE_BLSCFG}" != "xtrue" ]; then
+      gettext_printf "Found initrd image: %s\n" "${dirname}/${initramfs}" >&2
+    fi
+  elif test -z "${initramfs}" ; then
     # "UUID=" and "ZFS=" magic is parsed by initrd or initramfs.  Since there's
     # no initrd or builtin initramfs, it can't work here.
     if [ "x${GRUB_DEVICE_PARTUUID}" = "x" ] \