From 4d7c81f7b4ff4ca7b2a84632f2f0b89d5af58bbf Mon Sep 17 00:00:00 2001 From: Neal Gompa Date: Aug 27 2020 00:53:20 +0000 Subject: [PATCH 1/2] Populate fstab(5) and bootloader configuration for Btrfs subvolumes In order for an image to be setup fully on boot, we need to populate fstab(5) configuration and ensure the bootloader has the right references for where the Btrfs filesystems are located on the disk. --- diff --git a/appcreate/appliance.py b/appcreate/appliance.py index a1a0a67..03d119a 100644 --- a/appcreate/appliance.py +++ b/appcreate/appliance.py @@ -76,23 +76,36 @@ class ApplianceImageCreator(ImageCreator): self.grub2inst_params = [] def _get_fstab(self): - s = "" + f = "" + has_btrfs_subvolumes = False for mp in self.__instloop.mountOrder: p = None for p1 in self.__instloop.partitions: + if p1['fstype'] == "btrfs" and not p1['mountpoint'].startswith('/'): + # This btrfs filesystem uses subvolumes + has_btrfs_subvolumes = True if p1['mountpoint'] == mp: p = p1 break - + if p['fstype'] == "btrfs" and not p['mountpoint'].startswith('/'): + # There's no mountpoint to export to fstab, so skip + continue if not p['UUID'] is None: - mountdev = p['UUID'] + mountdev = "UUID=%s" % p['UUID'] else: mountdev = "LABEL=_%s" % p['mountpoint'] - s += "%(mountdev)s %(mountpoint)s %(fstype)s defaults,noatime 0 0\n" % { + f += "%(mountdev)s %(mountpoint)s %(fstype)s defaults,noatime 0 0\n" % { 'mountdev': mountdev, 'mountpoint': p['mountpoint'], 'fstype': p['fstype'] } - return s + if has_btrfs_subvolumes: + for s in self.__instloop.subvolumes: + f += "%(mountdev)s %(mountpoint)s %(fstype)s subvol=%(name)s,noatime 0 0\n" % { + 'mountdev': "UUID=%s" % s['UUID'], + 'mountpoint': s['mountpoint'], + 'fstype': "btrfs", + 'name': s['name'] } + return f def _create_mkinitrd_config(self): #write to tell which modules to be included in initrd @@ -282,6 +295,7 @@ class ApplianceImageCreator(ImageCreator): cfg.close() def _get_grub_boot_config(self): + btrfsboot = False bootdevnum = None rootdevnum = None rootdev = None @@ -298,8 +312,17 @@ class ApplianceImageCreator(ImageCreator): else: rootdev = "LABEL=_/" + for s in self.__instloop.subvolumes: + if s['mountpoint'] == "/boot": + btrfsboot = True + bootdevnum = s['num'] - 1 + + if s['mountpoint'] == "/": + rootdevnum = s['num'] - 1 + rootdev = s['UUID'] + prefix = "" - if bootdevnum == rootdevnum: + if bootdevnum == rootdevnum and not btrfsboot: prefix = "/boot" return (bootdevnum, rootdevnum, rootdev, prefix) @@ -343,6 +366,7 @@ class ApplianceImageCreator(ImageCreator): cfg.close() def _get_extlinux_boot_config(self): + btrfsboot = False bootdevnum = None rootdevnum = None rootdev = None @@ -358,8 +382,16 @@ class ApplianceImageCreator(ImageCreator): rootdev = p['UUID'] else: rootdev = "LABEL=_/" + for s in self.__instloop.subvolumes: + if s['mountpoint'] == "/boot": + btrfsboot = True + bootdevnum = s['num'] - 1 + + if s['mountpoint'] == "/": + rootdevnum = s['num'] - 1 + rootdev = s['UUID'] prefix = "" - if bootdevnum == rootdevnum: + if bootdevnum == rootdevnum and not btrfsboot: prefix = "/boot" return (bootdevnum, rootdevnum, rootdev, prefix) diff --git a/appcreate/partitionedfs.py b/appcreate/partitionedfs.py index 50206c4..9e81d2e 100644 --- a/appcreate/partitionedfs.py +++ b/appcreate/partitionedfs.py @@ -66,7 +66,12 @@ class PartitionedMount(Mount): 'num': None}) # Partition number def add_subvolume(self, parent, mountpoint, name): - self.subvolumes.append({'parent': parent, 'mountpoint': mountpoint, 'name': name}) + self.subvolumes.append({'parent': parent, # parent location for subvolume + 'mountpoint': mountpoint, # Mount relative to chroot + 'name': name, # subvolume name + 'device': None, # kpartx device node for partition + 'UUID': None, # UUID for partition + 'num': None}) # Partition number def __format_disks(self): logging.debug("Formatting disks") @@ -299,11 +304,14 @@ class PartitionedMount(Mount): others = [] ordered = [] for s in self.subvolumes: + s['device'] = subprocess.Popen(["findmnt", "-n", "-o", "SOURCE", "%s%s" % (self.mountdir, s['parent'])], stdout=subprocess.PIPE).communicate()[0].decode("utf-8").strip() + s['UUID'] = self.__getuuid(s['device']) + s['num'] = int(s['device'].rsplit('p', 1)[1]) if s['mountpoint'] == '/': ordered.append(s) else: others.append(s) - + ordered += others for s in ordered: base = "%s%s" % (self.mountdir, s['parent']) @@ -313,8 +321,7 @@ class PartitionedMount(Mount): subprocess.call(['btrfs', 'subvol', 'create', path]) subprocess.call(['mkdir', '-p', mountpath]) logging.debug("Mounting Btrfs subvolume %s at path %s" % (s['name'], mountpath)) - device = subprocess.Popen(["findmnt", "-n", "-o", "SOURCE", base], stdout=subprocess.PIPE).communicate()[0].decode("utf-8").strip() - subprocess.call(['mount', '-t', 'btrfs', '-o', 'subvol=%s' % s['name'], device, mountpath]) + subprocess.call(['mount', '-t', 'btrfs', '-o', 'subvol=%s' % s['name'], s['device'], mountpath]) def mount(self): for dev in list(self.disks.keys()): From 18f0b3a4712823cf90c4af7541f678a69ca53adb Mon Sep 17 00:00:00 2001 From: Neal Gompa Date: Aug 27 2020 01:10:30 +0000 Subject: [PATCH 2/2] appcreate/partitionedfs: Ensure __getuuid() actually gets the UUID With Btrfs, UUID and UUID_SUB are both provided by blkid(8). In order for the right value to be selected, we need to be a tiny bit stricter to ensure we get the right UUID value. --- diff --git a/appcreate/partitionedfs.py b/appcreate/partitionedfs.py index 9e81d2e..1e9fdde 100644 --- a/appcreate/partitionedfs.py +++ b/appcreate/partitionedfs.py @@ -398,7 +398,7 @@ class PartitionedMount(Mount): devdata = subprocess.Popen(["/sbin/blkid", partition], stdout=subprocess.PIPE) devdataout = devdata.communicate()[0].decode("utf-8").split() for data in devdataout: - if data.startswith("UUID"): + if data.startswith("UUID="): UUID = data.replace('"', '') continue return UUID