From 17f972b6fb172fe19d6e115a20664eefdbd3838d Mon Sep 17 00:00:00 2001

From: Eduardo Otubo <otubo@redhat.com>

Date: Mon, 24 Aug 2020 15:25:38 +0200

Subject: [PATCH 3/3] Detect kernel version before swap file creation (#428)

RH-Author: Eduardo Otubo <otubo@redhat.com>

Message-id: <20200820092042.5418-4-otubo@redhat.com>

Patchwork-id: 98191

O-Subject: [RHEL-8.3.0 cloud-init PATCH 3/3] Detect kernel version before swap file creation (#428)

Bugzilla: 1794664

RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

RH-Acked-by: Mohammed Gamal <mgamal@redhat.com>

commit b749548a9eb43b34cce64f8688107645411abc8c

Author: Eduardo Otubo <otubo@redhat.com>

Date:   Tue Aug 18 23:12:02 2020 +0200

    Detect kernel version before swap file creation (#428)

    According to man page `man 8 swapon', "Preallocated swap files are

    supported on XFS since Linux 4.18". This patch checks for kernel version

    before attepting to create swapfile, using dd for XFS only on kernel

    versions <= 4.18 or btrfs.

    Add new func util.kernel_version which returns a tuple of ints (major, minor)

    Signed-off-by: Eduardo Otubo otubo@redhat.com

Signed-off-by: Eduardo Otubo otubo@redhat.com

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 cloudinit/config/cc_mounts.py                      |   8 +-

 cloudinit/util.py                                  |   4 +

 .../unittests/test_handler/test_handler_mounts.py  | 107 +++++++++++++++++++++

 tests/unittests/test_util.py                       |  15 +++

 4 files changed, 131 insertions(+), 3 deletions(-)

diff --git a/cloudinit/config/cc_mounts.py b/cloudinit/config/cc_mounts.py

index 0573026..e1c43e3 100644

--- a/cloudinit/config/cc_mounts.py

+++ b/cloudinit/config/cc_mounts.py

@@ -65,7 +65,7 @@ swap file is created.

 from string import whitespace

 import logging

-import os.path

+import os

 import re

 from cloudinit import type_utils

@@ -249,7 +249,8 @@ def create_swapfile(fname, size):

     fstype = util.get_mount_info(swap_dir)[1]

-    if fstype in ("xfs", "btrfs"):

+    if (fstype == "xfs" and

+            util.kernel_version() < (4, 18)) or fstype == "btrfs":

         create_swap(fname, size, "dd")

     else:

         try:

@@ -259,7 +260,8 @@ def create_swapfile(fname, size):

             LOG.warning("Will attempt with dd.")

             create_swap(fname, size, "dd")

-    util.chmod(fname, 0o600)

+    if os.path.exists(fname):

+        util.chmod(fname, 0o600)

     try:

         util.subp(['mkswap', fname])

     except util.ProcessExecutionError:

diff --git a/cloudinit/util.py b/cloudinit/util.py

index 5d51ba8..ad89376 100644

--- a/cloudinit/util.py

+++ b/cloudinit/util.py

@@ -79,6 +79,10 @@ CONTAINER_TESTS = (['systemd-detect-virt', '--quiet', '--container'],

                    ['lxc-is-container'])

+def kernel_version():

+    return tuple(map(int, os.uname().release.split('.')[:2]))

+

+

 @lru_cache()

 def get_architecture(target=None):

     out, _ = subp(['dpkg', '--print-architecture'], capture=True,

diff --git a/tests/unittests/test_handler/test_handler_mounts.py b/tests/unittests/test_handler/test_handler_mounts.py

index 7bcefa0..27bcc6f 100644

--- a/tests/unittests/test_handler/test_handler_mounts.py

+++ b/tests/unittests/test_handler/test_handler_mounts.py

@@ -132,6 +132,113 @@ class TestSanitizeDevname(test_helpers.FilesystemMockingTestCase):

                 'ephemeral0.1', lambda x: disk_path, mock.Mock()))

+class TestSwapFileCreation(test_helpers.FilesystemMockingTestCase):

+

+    def setUp(self):

+        super(TestSwapFileCreation, self).setUp()

+        self.new_root = self.tmp_dir()

+        self.patchOS(self.new_root)

+

+        self.fstab_path = os.path.join(self.new_root, 'etc/fstab')

+        self.swap_path = os.path.join(self.new_root, 'swap.img')

+        self._makedirs('/etc')

+

+        self.add_patch('cloudinit.config.cc_mounts.FSTAB_PATH',

+                       'mock_fstab_path',

+                       self.fstab_path,

+                       autospec=False)

+

+        self.add_patch('cloudinit.config.cc_mounts.subp.subp',

+                       'm_subp_subp')

+

+        self.add_patch('cloudinit.config.cc_mounts.util.mounts',

+                       'mock_util_mounts',

+                       return_value={

+                           '/dev/sda1': {'fstype': 'ext4',

+                                         'mountpoint': '/',

+                                         'opts': 'rw,relatime,discard'

+                                         }})

+

+        self.mock_cloud = mock.Mock()

+        self.mock_log = mock.Mock()

+        self.mock_cloud.device_name_to_device = self.device_name_to_device

+

+        self.cc = {

+            'swap': {

+                'filename': self.swap_path,

+                'size': '512',

+                'maxsize': '512'}}

+

+    def _makedirs(self, directory):

+        directory = os.path.join(self.new_root, directory.lstrip('/'))

+        if not os.path.exists(directory):

+            os.makedirs(directory)

+

+    def device_name_to_device(self, path):

+        if path == 'swap':

+            return self.swap_path

+        else:

+            dev = None

+

+        return dev

+

+    @mock.patch('cloudinit.util.get_mount_info')

+    @mock.patch('cloudinit.util.kernel_version')

+    def test_swap_creation_method_fallocate_on_xfs(self, m_kernel_version,

+                                                   m_get_mount_info):

+        m_kernel_version.return_value = (4, 20)

+        m_get_mount_info.return_value = ["", "xfs"]

+

+        cc_mounts.handle(None, self.cc, self.mock_cloud, self.mock_log, [])

+        self.m_subp_subp.assert_has_calls([

+            mock.call(['fallocate', '-l', '0M', self.swap_path], capture=True),

+            mock.call(['mkswap', self.swap_path]),

+            mock.call(['swapon', '-a'])])

+

+    @mock.patch('cloudinit.util.get_mount_info')

+    @mock.patch('cloudinit.util.kernel_version')

+    def test_swap_creation_method_xfs(self, m_kernel_version,

+                                      m_get_mount_info):

+        m_kernel_version.return_value = (3, 18)

+        m_get_mount_info.return_value = ["", "xfs"]

+

+        cc_mounts.handle(None, self.cc, self.mock_cloud, self.mock_log, [])

+        self.m_subp_subp.assert_has_calls([

+            mock.call(['dd', 'if=/dev/zero',

+                       'of=' + self.swap_path,

+                       'bs=1M', 'count=0'], capture=True),

+            mock.call(['mkswap', self.swap_path]),

+            mock.call(['swapon', '-a'])])

+

+    @mock.patch('cloudinit.util.get_mount_info')

+    @mock.patch('cloudinit.util.kernel_version')

+    def test_swap_creation_method_btrfs(self, m_kernel_version,

+                                        m_get_mount_info):

+        m_kernel_version.return_value = (4, 20)

+        m_get_mount_info.return_value = ["", "btrfs"]

+

+        cc_mounts.handle(None, self.cc, self.mock_cloud, self.mock_log, [])

+        self.m_subp_subp.assert_has_calls([

+            mock.call(['dd', 'if=/dev/zero',

+                       'of=' + self.swap_path,

+                       'bs=1M', 'count=0'], capture=True),

+            mock.call(['mkswap', self.swap_path]),

+            mock.call(['swapon', '-a'])])

+

+    @mock.patch('cloudinit.util.get_mount_info')

+    @mock.patch('cloudinit.util.kernel_version')

+    def test_swap_creation_method_ext4(self, m_kernel_version,

+                                       m_get_mount_info):

+        m_kernel_version.return_value = (5, 14)

+        m_get_mount_info.return_value = ["", "ext4"]

+

+        cc_mounts.handle(None, self.cc, self.mock_cloud, self.mock_log, [])

+        self.m_subp_subp.assert_has_calls([

+            mock.call(['fallocate', '-l', '0M', self.swap_path], capture=True),

+            mock.call(['mkswap', self.swap_path]),

+            mock.call(['swapon', '-a'])])

+

+

 class TestFstabHandling(test_helpers.FilesystemMockingTestCase):

     swap_path = '/dev/sdb1'

diff --git a/tests/unittests/test_util.py b/tests/unittests/test_util.py

index 0e71db8..87dc8dd 100644

--- a/tests/unittests/test_util.py

+++ b/tests/unittests/test_util.py

@@ -1177,4 +1177,19 @@ class TestGetProcEnv(helpers.TestCase):

         my_ppid = os.getppid()

         self.assertEqual(my_ppid, util.get_proc_ppid(my_pid))

+

+class TestKernelVersion():

+    """test kernel version function"""

+

+    params = [

+        ('5.6.19-300.fc32.x86_64', (5, 6)),

+        ('4.15.0-101-generic', (4, 15)),

+        ('3.10.0-1062.12.1.vz7.131.10', (3, 10)),

+        ('4.18.0-144.el8.x86_64', (4, 18))]

+

+    @mock.patch('os.uname')

+    @pytest.mark.parametrize("uname_release,expected", params)

+    def test_kernel_version(self, m_uname, uname_release, expected):

+        m_uname.return_value.release = uname_release

+        assert expected == util.kernel_version()

 # vi: ts=4 expandtab

-- 

1.8.3.1