From eb16230427fc1081f8515e6ad69ccf99ca521e5d Mon Sep 17 00:00:00 2001

From: Vojtech Trefny <vtrefny@redhat.com>

Date: Tue, 4 Apr 2023 13:31:40 +0200

Subject: [PATCH 1/2] Add support for filesystem online resize

Resolves: rhbz#2168680

---

 blivet/devices/lvm.py       | 13 ++++++++-----

 blivet/devices/partition.py | 11 ++++++-----

 blivet/flags.py             |  3 +++

 blivet/formats/fs.py        | 32 ++++++++++++++++++++++++++++----

 blivet/formats/fslib.py     |  7 +++++++

 5 files changed, 52 insertions(+), 14 deletions(-)

diff --git a/blivet/devices/lvm.py b/blivet/devices/lvm.py

index c3132457..ca45c4b5 100644

--- a/blivet/devices/lvm.py

+++ b/blivet/devices/lvm.py

@@ -42,6 +42,7 @@ from .. import errors

 from .. import util

 from ..storage_log import log_method_call

 from .. import udev

+from ..flags import flags

 from ..size import Size, KiB, MiB, ROUND_UP, ROUND_DOWN

 from ..static_data.lvm_info import lvs_info

 from ..tasks import availability

@@ -2729,12 +2730,14 @@ class LVMLogicalVolumeDevice(LVMLogicalVolumeBase, LVMInternalLogicalVolumeMixin

         # Setup VG parents (in case they are dmraid partitions for example)

         self.vg.setup_parents(orig=True)

-        if self.original_format.exists:

-            self.original_format.teardown()

-        if self.format.exists:

-            self.format.teardown()

+        if not flags.allow_online_fs_resize:

+            if self.original_format.exists:

+                self.original_format.teardown()

+            if self.format.exists:

+                self.format.teardown()

+

+            udev.settle()

-        udev.settle()

         blockdev.lvm.lvresize(self.vg.name, self._name, self.size)

     @type_specific

diff --git a/blivet/devices/partition.py b/blivet/devices/partition.py

index 0e9250ce..6ae4b8d3 100644

--- a/blivet/devices/partition.py

+++ b/blivet/devices/partition.py

@@ -745,11 +745,12 @@ class PartitionDevice(StorageDevice):

         if not self.exists:

             raise errors.DeviceError("device has not been created")

-        # don't teardown when resizing luks

-        if self.format.type == "luks" and self.children:

-            self.children[0].format.teardown()

-        else:

-            self.teardown()

+        if not flags.allow_online_fs_resize:

+            # don't teardown when resizing luks

+            if self.format.type == "luks" and self.children:

+                self.children[0].format.teardown()

+            else:

+                self.teardown()

         if not self.sysfs_path:

             return

diff --git a/blivet/flags.py b/blivet/flags.py

index 6364164d..ecfa7ad7 100644

--- a/blivet/flags.py

+++ b/blivet/flags.py

@@ -91,6 +91,9 @@ class Flags(object):

         self.debug_threads = False

+        # Allow online filesystem resizes

+        self.allow_online_fs_resize = False

+

     def get_boot_cmdline(self):

         with open("/proc/cmdline") as f:

             buf = f.read().strip()

diff --git a/blivet/formats/fs.py b/blivet/formats/fs.py

index 33922f3a..3f553eb0 100644

--- a/blivet/formats/fs.py

+++ b/blivet/formats/fs.py

@@ -56,7 +56,7 @@ from ..i18n import N_

 from .. import udev

 from ..mounts import mounts_cache

-from .fslib import kernel_filesystems

+from .fslib import kernel_filesystems, FSResize

 import logging

 log = logging.getLogger("blivet")

@@ -88,6 +88,9 @@ class FS(DeviceFormat):

     # value is already unpredictable and can change in the future...

     _metadata_size_factor = 1.0

+    # support for resize: grow/shrink, online/offline

+    _resize_support = 0

+

     config_actions_map = {"label": "write_label"}

     def __init__(self, **kwargs):

@@ -436,12 +439,27 @@ class FS(DeviceFormat):

             self.write_uuid()

     def _pre_resize(self):

-        # file systems need a check before being resized

-        self.do_check()

+        if self.status:

+            if flags.allow_online_fs_resize:

+                if self.target_size > self.size and not self._resize_support & FSResize.ONLINE_GROW:

+                    raise FSError("This filesystem doesn't support online growing")

+                if self.target_size < self.size and not self._resize_support & FSResize.ONLINE_SHRINK:

+                    raise FSError("This filesystem doesn't support online shrinking")

+            else:

+                raise FSError("Resizing of mounted filesystems is disabled")

+

+        if self.status:

+            # fsck tools in general don't allow checks on mounted filesystems

+            log.debug("Filesystem on %s is mounted, not checking", self.device)

+        else:

+            # file systems need a check before being resized

+            self.do_check()

+

         super(FS, self)._pre_resize()

     def _post_resize(self):

-        self.do_check()

+        if not self.status:

+            self.do_check()

         super(FS, self)._post_resize()

     def do_check(self):

@@ -838,6 +856,7 @@ class Ext2FS(FS):

     _formattable = True

     _supported = True

     _resizable = True

+    _resize_support = FSResize.ONLINE_GROW | FSResize.OFFLINE_GROW | FSResize.OFFLINE_SHRINK

     _linux_native = True

     _max_size = Size("8 TiB")

     _dump = True

@@ -1097,6 +1116,7 @@ class XFS(FS):

     _linux_native = True

     _supported = True

     _resizable = True

+    _resize_support = FSResize.ONLINE_GROW | FSResize.OFFLINE_GROW

     _packages = ["xfsprogs"]

     _fsck_class = fsck.XFSCK

     _info_class = fsinfo.XFSInfo

@@ -1247,6 +1267,7 @@ class NTFS(FS):

     _labelfs = fslabeling.NTFSLabeling()

     _uuidfs = fsuuid.NTFSUUID()

     _resizable = True

+    _resize_support = FSResize.OFFLINE_GROW | FSResize.OFFLINE_SHRINK

     _formattable = True

     _supported = True

     _min_size = Size("1 MiB")

@@ -1490,6 +1511,9 @@ class TmpFS(NoDevFS):

         # same, nothing actually needs to be set

         pass

+    def _pre_resize(self):

+        self.do_check()

+

     def do_resize(self):

         # Override superclass method to record whether mount options

         # should include an explicit size specification.

diff --git a/blivet/formats/fslib.py b/blivet/formats/fslib.py

index ea93b1fd..8722e942 100644

--- a/blivet/formats/fslib.py

+++ b/blivet/formats/fslib.py

@@ -36,3 +36,10 @@ def update_kernel_filesystems():

 update_kernel_filesystems()

+

+

+class FSResize():

+    OFFLINE_SHRINK = 1 << 1

+    OFFLINE_GROW = 1 << 2

+    ONLINE_SHRINK = 1 << 3

+    ONLINE_GROW = 1 << 4

-- 

2.40.1

From 3fce5d0bfd7b09a976ff49feed15077477c6a425 Mon Sep 17 00:00:00 2001

From: Vojtech Trefny <vtrefny@redhat.com>

Date: Thu, 6 Apr 2023 14:02:11 +0200

Subject: [PATCH 2/2] Add a test case for filesystem online resize

Related: rhbz#2168680

---

 tests/storage_tests/formats_test/fs_test.py | 43 ++++++++++++++++++++-

 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/tests/storage_tests/formats_test/fs_test.py b/tests/storage_tests/formats_test/fs_test.py

index 97f4cbbe..1d42dc21 100644

--- a/tests/storage_tests/formats_test/fs_test.py

+++ b/tests/storage_tests/formats_test/fs_test.py

@@ -6,9 +6,10 @@ import parted

 import blivet.formats.fs as fs

 from blivet.size import Size, ROUND_DOWN

-from blivet.errors import DeviceFormatError

+from blivet.errors import DeviceFormatError, FSError

 from blivet.formats import get_format

 from blivet.devices import PartitionDevice, DiskDevice

+from blivet.flags import flags

 from .loopbackedtestcase import LoopBackedTestCase

@@ -26,6 +27,46 @@ class Ext3FSTestCase(Ext2FSTestCase):

 class Ext4FSTestCase(Ext3FSTestCase):

     _fs_class = fs.Ext4FS

+    def test_online_resize(self):

+        an_fs = self._fs_class()

+        if not an_fs.formattable:

+            self.skipTest("can not create filesystem %s" % an_fs.name)

+        an_fs.device = self.loop_devices[0]

+        self.assertIsNone(an_fs.create())

+        an_fs.update_size_info()

+

+        if not self.can_resize(an_fs):

+            self.skipTest("filesystem is not resizable")

+

+        # shrink offline first (ext doesn't support online shrinking)

+        TARGET_SIZE = Size("64 MiB")

+        an_fs.target_size = TARGET_SIZE

+        self.assertEqual(an_fs.target_size, TARGET_SIZE)

+        self.assertNotEqual(an_fs._size, TARGET_SIZE)

+        self.assertIsNone(an_fs.do_resize())

+

+        with tempfile.TemporaryDirectory() as mountpoint:

+            an_fs.mount(mountpoint=mountpoint)

+

+            # grow back when mounted

+            TARGET_SIZE = Size("100 MiB")

+            an_fs.target_size = TARGET_SIZE

+            self.assertEqual(an_fs.target_size, TARGET_SIZE)

+            self.assertNotEqual(an_fs._size, TARGET_SIZE)

+

+            # should fail, online resize disabled by default

+            with self.assertRaisesRegex(FSError, "Resizing of mounted filesystems is disabled"):

+                an_fs.do_resize()

+

+            # enable online resize

+            flags.allow_online_fs_resize = True

+            an_fs.do_resize()

+            flags.allow_online_fs_resize = False

+            self._test_sizes(an_fs)

+            self.assertEqual(an_fs.system_mountpoint, mountpoint)

+

+            an_fs.unmount()

+

 class FATFSTestCase(fstesting.FSAsRoot):

     _fs_class = fs.FATFS

-- 

2.40.1