| index : archinstall32 | |
| Archlinux32 installer | gitolite user |
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| -rw-r--r-- | archinstall/lib/disk/btrfs/__init__.py | 182 |
diff --git a/archinstall/lib/disk/btrfs/__init__.py b/archinstall/lib/disk/btrfs/__init__.py new file mode 100644 index 00000000..84b9c0f6 --- /dev/null +++ b/archinstall/lib/disk/btrfs/__init__.py @@ -0,0 +1,182 @@ +from __future__ import annotations +import pathlib +import glob +import logging +import re +from typing import Union, Dict, TYPE_CHECKING, Any, Iterator + +# https://stackoverflow.com/a/39757388/929999 +if TYPE_CHECKING: + from ...installer import Installer + +from .btrfs_helpers import ( + subvolume_info_from_path as subvolume_info_from_path, + find_parent_subvolume as find_parent_subvolume, + setup_subvolumes as setup_subvolumes, + mount_subvolume as mount_subvolume +) +from .btrfssubvolume import BtrfsSubvolume as BtrfsSubvolume +from .btrfspartition import BTRFSPartition as BTRFSPartition + +from ..helpers import get_mount_info +from ...exceptions import DiskError, Deprecated +from ...general import SysCommand +from ...output import log +from ...exceptions import SysCallError + +def get_subvolume_info(path :pathlib.Path) -> Dict[str, Any]: + try: + output = SysCommand(f"btrfs subvol show {path}").decode() + except SysCallError as error: + print('Error:', error) + + result = {} + for line in output.replace('\r\n', '\n').split('\n'): + if ':' in line: + key, val = line.replace('\t', '').split(':', 1) + result[key.strip().lower().replace(' ', '_')] = val.strip() + + return result + +def create_subvolume(installation :Installer, subvolume_location :Union[pathlib.Path, str]) -> bool: + """ + This function uses btrfs to create a subvolume. + + @installation: archinstall.Installer instance + @subvolume_location: a localized string or path inside the installation / or /boot for instance without specifying /mnt/boot + """ + + installation_mountpoint = installation.target + if type(installation_mountpoint) == str: + installation_mountpoint = pathlib.Path(installation_mountpoint) + # Set up the required physical structure + if type(subvolume_location) == str: + subvolume_location = pathlib.Path(subvolume_location) + + target = installation_mountpoint / subvolume_location.relative_to(subvolume_location.anchor) + + # Difference from mount_subvolume: + # We only check if the parent exists, since we'll run in to "target path already exists" otherwise + if not target.parent.exists(): + target.parent.mkdir(parents=True) + + if glob.glob(str(target / '*')): + raise DiskError(f"Cannot create subvolume at {target} because it contains data (non-empty folder target)") + + # Remove the target if it exists + if target.exists(): + target.rmdir() + + log(f"Creating a subvolume on {target}", level=logging.INFO) + if (cmd := SysCommand(f"btrfs subvolume create {target}")).exit_code != 0: + raise DiskError(f"Could not create a subvolume at {target}: {cmd}") + +def _has_option(option :str,options :list) -> bool: + """ auxiliary routine to check if an option is present in a list. + we check if the string appears in one of the options, 'cause it can appear in severl forms (option, option=val,...) + """ + if not options: + return False + + for item in options: + if option in item: + return True + + return False + +def manage_btrfs_subvolumes(installation :Installer, + partition :Dict[str, str],) -> list: + + raise Deprecated("Use setup_subvolumes() instead.") + + from copy import deepcopy + """ we do the magic with subvolumes in a centralized place + parameters: + * the installation object + * the partition dictionary entry which represents the physical partition + returns + * mountpoinst, the list which contains all the "new" partititon to be mounted + + We expect the partition has been mounted as / , and it to be unmounted after the processing + Then we create all the subvolumes inside btrfs as demand + We clone then, both the partition dictionary and the object inside it and adapt it to the subvolume needs + Then we return a list of "new" partitions to be processed as "normal" partitions + # TODO For encrypted devices we need some special processing prior to it + """ + # We process each of the pairs <subvolume name: mount point | None | mount info dict> + # th mount info dict has an entry for the path of the mountpoint (named 'mountpoint') and 'options' which is a list + # of mount options (or similar used by brtfs) + mountpoints = [] + subvolumes = partition['btrfs']['subvolumes'] + for name, right_hand in subvolumes.items(): + try: + # we normalize the subvolume name (getting rid of slash at the start if exists. In our implemenation has no semantic load - every subvolume is created from the top of the hierarchy- and simplifies its further use + if name.startswith('/'): + name = name[1:] + # renormalize the right hand. + location = None + subvol_options = [] + # no contents, so it is not to be mounted + if not right_hand: + location = None + # just a string. per backward compatibility the mount point + elif isinstance(right_hand,str): + location = right_hand + # a dict. two elements 'mountpoint' (obvious) and and a mount options list ¿? + elif isinstance(right_hand,dict): + location = right_hand.get('mountpoint',None) + subvol_options = right_hand.get('options',[]) + # we create the subvolume + create_subvolume(installation,name) + # Make the nodatacow processing now + # It will be the main cause of creation of subvolumes which are not to be mounted + # it is not an options which can be established by subvolume (but for whole file systems), and can be + # set up via a simple attribute change in a directory (if empty). And here the directories are brand new + if 'nodatacow' in subvol_options: + if (cmd := SysCommand(f"chattr +C {installation.target}/{name}")).exit_code != 0: + raise DiskError(f"Could not set nodatacow attribute at {installation.target}/{name}: {cmd}") + # entry is deleted so nodatacow doesn't propagate to the mount options + del subvol_options[subvol_options.index('nodatacow')] + # Make the compress processing now + # it is not an options which can be established by subvolume (but for whole file systems), and can be + # set up via a simple attribute change in a directory (if empty). And here the directories are brand new + # in this way only zstd compression is activaded + # TODO WARNING it is not clear if it should be a standard feature, so it might need to be deactivated + if 'compress' in subvol_options: + if not _has_option('compress',partition.get('filesystem',{}).get('mount_options',[])): + if (cmd := SysCommand(f"chattr +c {installation.target}/{name}")).exit_code != 0: + raise DiskError(f"Could not set compress attribute at {installation.target}/{name}: {cmd}") + # entry is deleted so compress doesn't propagate to the mount options + del subvol_options[subvol_options.index('compress')] + # END compress processing. + # we do not mount if THE basic partition will be mounted or if we exclude explicitly this subvolume + if not partition['mountpoint'] and location is not None: + # we begin to create a fake partition entry. First we copy the original -the one that corresponds to + # the primary partition. We make a deepcopy to avoid altering the original content in any case + fake_partition = deepcopy(partition) + # we start to modify entries in the "fake partition" to match the needs of the subvolumes + # to avoid any chance of entering in a loop (not expected) we delete the list of subvolumes in the copy + del fake_partition['btrfs'] + fake_partition['encrypted'] = False + fake_partition['generate-encryption-key-file'] = False + # Mount destination. As of now the right hand part + fake_partition['mountpoint'] = location + # we load the name in an attribute called subvolume, but i think it is not needed anymore, 'cause the mount logic uses a different path. + fake_partition['subvolume'] = name + # here we add the special mount options for the subvolume, if any. + # if the original partition['options'] is not a list might give trouble + if fake_partition.get('filesystem',{}).get('mount_options',[]): + fake_partition['filesystem']['mount_options'].extend(subvol_options) + else: + fake_partition['filesystem']['mount_options'] = subvol_options + # Here comes the most exotic part. The dictionary attribute 'device_instance' contains an instance of Partition. This instance will be queried along the mount process at the installer. + # As the rest will query there the path of the "partition" to be mounted, we feed it with the bind name needed to mount subvolumes + # As we made a deepcopy we have a fresh instance of this object we can manipulate problemless + fake_partition['device_instance'].path = f"{partition['device_instance'].path}[/{name}]" + + # Well, now that this "fake partition" is ready, we add it to the list of the ones which are to be mounted, + # as "normal" ones + mountpoints.append(fake_partition) + except Exception as e: + raise e + return mountpoints |