Finalized the create_subvolume and mount_subvolume functions. Remaining is to call these functions during the disk setup process to create the subvolumes and mount them in place, rather than doing the normal steps.

archinstall/lib/disk/btrfs.py

@@ -1,4 +1,36 @@
+import pathlib, glob
+from typing import Union
+from .helpers import get_mount_info
+from ..exceptions import DiskError
 from ..general import SysCommand
 
-def create_subvolume(installation):
-	SysCommand(f"btrfs subvolume create {installation.target}/@")
+def mount_subvolume(installation, location :Union[pathlib.Path, str], force=False) -> bool:
+	"""
+	This function uses mount to mount a subvolume on a given device, at a given location with a given subvolume name.
+
+	@installation: archinstall.Installer instance
+	@location: a localized string or path inside the installation / or /boot for instance without specifying /mnt/boot
+	@force: overrides the check for weither or not the subvolume mountpoint is empty or not
+	"""
+	# Set up the required physical structure
+	if type(location) == str:
+		location = pathlib.Path(location)
+
+	if not location.exists():
+		location.mkdir(parents=True)
+
+	if glob.glob(str(installation.target/location/'*')) and force is False:
+		raise DiskError(f"Cannot mount subvolume to {installation.target/location} because it contains data (non-empty folder target)")
+	
+	# Mount the logical volume to the physical structure
+	return SysCommand(f"mount {get_mount_info(installation.target/location)['source']} {installation.target}/{str(location)} -o subvol=@/{str(location)}").exit_code == 0
+
+def create_subvolume(installation, location :Union[pathlib.Path, str]) -> bool:
+	"""
+	This function uses btrfs to create a subvolume.
+
+	@installation: archinstall.Installer instance
+	@location: a localized string or path inside the installation / or /boot for instance without specifying /mnt/boot
+	"""
+
+	SysCommand(f"btrfs subvolume create {installation.target}/{str(location)}")

archinstall/lib/disk/helpers.py

@@ -1,5 +1,7 @@
 import re
 import json
+import pathlib
+from typing import Union
 from .blockdevice import BlockDevice
 from ..exceptions import SysCallError
 from ..general import SysCommand
@@ -114,7 +116,7 @@ def harddrive(size=None, model=None, fuzzy=False):
 		return collection[drive]
 
 
-def get_mount_info(path) -> dict:
+def get_mount_info(path :Union[pathlib.Path, str]) -> dict:
 	try:
 		output = SysCommand(f'/usr/bin/findmnt --json {path}').decode('UTF-8')
 	except SysCallError: