From 80c988236fb476985826e85c5fbf6b101a60c39e Mon Sep 17 00:00:00 2001
From: Marian Stramm <m.stramm@speedcoding.de>
Date: Mon, 3 Jan 2022 01:39:12 +0100
Subject: [PATCH] pmb.install: add support for creating btrfs root filesystem
 (MR 2155)

in preparation for reversible upgrades, this change adds the option of
creating a btrfs root filesystem
---
 pmb/config/__init__.py | 3 ++-
 pmb/install/format.py  | 5 +++++
 pmb/parse/arguments.py | 2 +-
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/pmb/config/__init__.py b/pmb/config/__init__.py
index 4e246261..ea5264be 100644
--- a/pmb/config/__init__.py
+++ b/pmb/config/__init__.py
@@ -164,7 +164,8 @@ locales = [
 ]
 
 # Supported filesystems and their fstools packages
-filesystems = {"ext2": "e2fsprogs",
+filesystems = {"btrfs": "btrfs-progs",
+               "ext2": "e2fsprogs",
                "ext4": "e2fsprogs",
                "f2fs": "f2fs-tools",
                "fat16": "dosfstools",
diff --git a/pmb/install/format.py b/pmb/install/format.py
index da1c31ad..d9bdbaae 100644
--- a/pmb/install/format.py
+++ b/pmb/install/format.py
@@ -35,6 +35,9 @@ def format_and_mount_boot(args, boot_label):
     elif filesystem == "ext2":
         pmb.chroot.root(args, ["mkfs.ext2", "-F", "-q", "-L", boot_label,
                                device])
+    elif filesystem == "btrfs":
+        pmb.chroot.root(args, ["mkfs.btrfs", "-f", "-q", "-L", boot_label,
+                               device])
     else:
         raise RuntimeError("Filesystem " + filesystem + " is not supported!")
     pmb.chroot.root(args, ["mkdir", "-p", mountpoint])
@@ -106,6 +109,8 @@ def format_and_mount_root(args, device, root_label, sdcard):
                 mkfs_root_args = mkfs_root_args + ["-N", "100000"]
         elif filesystem == "f2fs":
             mkfs_root_args = ["mkfs.f2fs", "-f", "-l", root_label]
+        elif filesystem == "btrfs":
+            mkfs_root_args = ["mkfs.btrfs", "-f", "-L", root_label]
         else:
             raise RuntimeError(f"Don't know how to format {filesystem}!")
 
diff --git a/pmb/parse/arguments.py b/pmb/parse/arguments.py
index 6d07aa0d..f71a31e2 100644
--- a/pmb/parse/arguments.py
+++ b/pmb/parse/arguments.py
@@ -162,7 +162,7 @@ def arguments_install(subparser):
     # Other
     group = ret.add_argument_group("other optional arguments")
     group.add_argument("--filesystem", help="root filesystem type",
-                       choices=["ext4", "f2fs"])
+                       choices=["ext4", "f2fs", "btrfs"])
 
 
 def arguments_export(subparser):