From a8d8a4a2efcaee578652ad82a1c7db2f69d44827 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Wed, 3 Oct 2018 20:00:19 +0200
Subject: [PATCH] Add --squashfs-only option to drop inner rootfs.img layer

Make runtime directly into squashfs image. This reduces largely
unreproducible ext4 layer, but requires anaconda's dracut module
modification to properly mount the image.

(cherry picked from commit 27e611629f2c654939b0894086512e9d4f366113)
---
 src/pylorax/__init__.py    | 16 ++++++++++++----
 src/pylorax/cmdline.py     |  2 ++
 src/pylorax/creator.py     |  2 +-
 src/pylorax/treebuilder.py | 11 ++++++++++-
 src/sbin/lorax             |  3 ++-
 5 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/src/pylorax/__init__.py b/src/pylorax/__init__.py
index 89baadb2..4f4fd837 100644
--- a/src/pylorax/__init__.py
+++ b/src/pylorax/__init__.py
@@ -186,7 +186,8 @@ class Lorax(BaseLoraxClass):
             add_arch_templates=None,
             add_arch_template_vars=None,
             verify=True,
-            user_dracut_args=None):
+            user_dracut_args=None,
+            squashfs_only=False):
 
         assert self._configured
 
@@ -318,9 +319,16 @@ class Lorax(BaseLoraxClass):
                 compressargs += ["-Xbcj", self.arch.bcj]
             else:
                 logger.info("no BCJ filter for arch %s", self.arch.basearch)
-        rb.create_runtime(joinpaths(installroot,runtime),
-                          compression=compression, compressargs=compressargs,
-                          size=size)
+        if squashfs_only:
+            # Create an ext4 rootfs.img and compress it with squashfs
+            rb.create_squashfs_runtime(joinpaths(installroot,runtime),
+                compression=compression, compressargs=compressargs,
+                size=size)
+        else:
+            # Create an ext4 rootfs.img and compress it with squashfs
+            rb.create_ext4_runtime(joinpaths(installroot,runtime),
+                compression=compression, compressargs=compressargs,
+                size=size)
         rb.finished()
 
         logger.info("preparing to build output tree and boot images")
diff --git a/src/pylorax/cmdline.py b/src/pylorax/cmdline.py
index 4e49fb1a..95b20841 100644
--- a/src/pylorax/cmdline.py
+++ b/src/pylorax/cmdline.py
@@ -109,6 +109,8 @@ def lorax_parser(dracut_default=""):
                           help="Do not verify SSL certificates")
     optional.add_argument("--dnfplugin", action="append", default=[], dest="dnfplugins",
                           help="Enable a DNF plugin by name/glob, or * to enable all of them.")
+    optional.add_argument("--squashfs-only", action="store_true", default=False,
+                          help="Use a plain squashfs filesystem for the runtime.")
 
     # dracut arguments
     dracut_group = parser.add_argument_group("dracut arguments")
diff --git a/src/pylorax/creator.py b/src/pylorax/creator.py
index e39e9fae..3a5fa029 100644
--- a/src/pylorax/creator.py
+++ b/src/pylorax/creator.py
@@ -203,7 +203,7 @@ def make_runtime(opts, mount_dir, work_dir, size=None):
     rb = RuntimeBuilder(product, arch, fake_dbo)
     compression, compressargs = squashfs_args(opts)
     log.info("Creating runtime")
-    rb.create_runtime(joinpaths(work_dir, RUNTIME), size=size,
+    rb.create_ext4_runtime(joinpaths(work_dir, RUNTIME), size=size,
                       compression=compression, compressargs=compressargs)
 
 
diff --git a/src/pylorax/treebuilder.py b/src/pylorax/treebuilder.py
index 0756804c..0fce0b83 100644
--- a/src/pylorax/treebuilder.py
+++ b/src/pylorax/treebuilder.py
@@ -215,7 +215,16 @@ class RuntimeBuilder(object):
             runcmd(["depmod", "-a", "-F", ksyms, "-b", root, kernel.version])
             generate_module_info(moddir+kernel.version, outfile=moddir+"module-info")
 
-    def create_runtime(self, outfile="/var/tmp/squashfs.img", compression="xz", compressargs=None, size=2):
+    def create_squashfs_runtime(self, outfile="/var/tmp/squashfs.img", compression="xz", compressargs=None, size=2):
+        """Create a plain squashfs runtime"""
+        compressargs = compressargs or []
+        os.makedirs(os.path.dirname(outfile))
+
+        # squash the rootfs
+        imgutils.mksquashfs(self.vars.root, outfile, compression, compressargs)
+
+    def create_ext4_runtime(self, outfile="/var/tmp/squashfs.img", compression="xz", compressargs=None, size=2):
+        """Create a squashfs compressed ext4 runtime"""
         # make live rootfs image - must be named "LiveOS/rootfs.img" for dracut
         compressargs = compressargs or []
         workdir = joinpaths(os.path.dirname(outfile), "runtime-workdir")
diff --git a/src/sbin/lorax b/src/sbin/lorax
index e1aa3729..eca8b0f0 100755
--- a/src/sbin/lorax
+++ b/src/sbin/lorax
@@ -196,7 +196,8 @@ def main():
               add_arch_templates=opts.add_arch_templates,
               add_arch_template_vars=parsed_add_arch_template_vars,
               remove_temp=True, verify=opts.verify,
-              user_dracut_args=opts.dracut_args)
+              user_dracut_args=opts.dracut_args,
+              squashfs_only=opts.squashfs_only)
 
     # Release the lock on the tempdir
     os.close(dir_fd)