cloud-init/SOURCES/ci-Do-not-use-fallocate-in-...

165 lines
6.0 KiB
Diff

From 49e5a49cc007b2a751eea212b4052e92837ebc8a Mon Sep 17 00:00:00 2001
From: Eduardo Otubo <otubo@redhat.com>
Date: Mon, 24 Aug 2020 15:25:34 +0200
Subject: [PATCH 1/3] Do not use fallocate in swap file creation on xfs. (#70)
RH-Author: Eduardo Otubo <otubo@redhat.com>
Message-id: <20200820092042.5418-2-otubo@redhat.com>
Patchwork-id: 98194
O-Subject: [RHEL-8.3.0 cloud-init PATCH 1/3] Do not use fallocate in swap file creation on xfs. (#70)
Bugzilla: 1794664
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Mohammed Gamal <mgamal@redhat.com>
commit 6603706eec1c39d9d591c8ffa0ef7171b74d84d6
Author: Eduardo Otubo <otubo@redhat.com>
Date: Thu Jan 23 17:41:48 2020 +0100
Do not use fallocate in swap file creation on xfs. (#70)
When creating a swap file on an xfs filesystem, fallocate cannot be used.
Doing so results in failure of swapon and a message like:
swapon: swapfile has holes
The solution here is to maintain a list (currently containing only XFS)
of filesystems where fallocate cannot be used. The, on those fileystems
use the slower but functional 'dd' method.
Signed-off-by: Eduardo Otubo <otubo@redhat.com>
Co-authored-by: Adam Dobrawy <naczelnik@jawnosc.tk>
Co-authored-by: Scott Moser <smoser@brickies.net>
Co-authored-by: Daniel Watkins <daniel@daniel-watkins.co.uk>
LP: #1781781
Signed-off-by: Eduardo Otubo <otubo@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
cloudinit/config/cc_mounts.py | 67 ++++++++++++++++------
.../unittests/test_handler/test_handler_mounts.py | 12 ++++
2 files changed, 62 insertions(+), 17 deletions(-)
diff --git a/cloudinit/config/cc_mounts.py b/cloudinit/config/cc_mounts.py
index c741c74..4293844 100644
--- a/cloudinit/config/cc_mounts.py
+++ b/cloudinit/config/cc_mounts.py
@@ -223,13 +223,58 @@ def suggested_swapsize(memsize=None, maxsize=None, fsys=None):
return size
+def create_swapfile(fname, size):
+ """Size is in MiB."""
+
+ errmsg = "Failed to create swapfile '%s' of size %dMB via %s: %s"
+
+ def create_swap(fname, size, method):
+ LOG.debug("Creating swapfile in '%s' on fstype '%s' using '%s'",
+ fname, fstype, method)
+
+ if method == "fallocate":
+ cmd = ['fallocate', '-l', '%dM' % size, fname]
+ elif method == "dd":
+ cmd = ['dd', 'if=/dev/zero', 'of=%s' % fname, 'bs=1M',
+ 'count=%d' % size]
+
+ try:
+ util.subp(cmd, capture=True)
+ except util.ProcessExecutionError as e:
+ LOG.warning(errmsg, fname, size, method, e)
+ util.del_file(fname)
+
+ swap_dir = os.path.dirname(fname)
+ util.ensure_dir(swap_dir)
+
+ fstype = util.get_mount_info(swap_dir)[1]
+
+ if fstype in ("xfs", "btrfs"):
+ create_swap(fname, size, "dd")
+ else:
+ try:
+ create_swap(fname, size, "fallocate")
+ except util.ProcessExecutionError as e:
+ LOG.warning(errmsg, fname, size, "dd", e)
+ LOG.warning("Will attempt with dd.")
+ create_swap(fname, size, "dd")
+
+ util.chmod(fname, 0o600)
+ try:
+ util.subp(['mkswap', fname])
+ except util.ProcessExecutionError:
+ util.del_file(fname)
+ raise
+
+
def setup_swapfile(fname, size=None, maxsize=None):
"""
fname: full path string of filename to setup
size: the size to create. set to "auto" for recommended
maxsize: the maximum size
"""
- tdir = os.path.dirname(fname)
+ swap_dir = os.path.dirname(fname)
+ mibsize = str(int(size / (2 ** 20)))
if str(size).lower() == "auto":
try:
memsize = util.read_meminfo()['total']
@@ -237,28 +282,16 @@ def setup_swapfile(fname, size=None, maxsize=None):
LOG.debug("Not creating swap: failed to read meminfo")
return
- util.ensure_dir(tdir)
- size = suggested_swapsize(fsys=tdir, maxsize=maxsize,
+ util.ensure_dir(swap_dir)
+ size = suggested_swapsize(fsys=swap_dir, maxsize=maxsize,
memsize=memsize)
if not size:
LOG.debug("Not creating swap: suggested size was 0")
return
- mbsize = str(int(size / (2 ** 20)))
- msg = "creating swap file '%s' of %sMB" % (fname, mbsize)
- try:
- util.ensure_dir(tdir)
- util.log_time(LOG.debug, msg, func=util.subp,
- args=[['sh', '-c',
- ('rm -f "$1" && umask 0066 && '
- '{ fallocate -l "${2}M" "$1" || '
- 'dd if=/dev/zero "of=$1" bs=1M "count=$2"; } && '
- 'mkswap "$1" || { r=$?; rm -f "$1"; exit $r; }'),
- 'setup_swap', fname, mbsize]])
-
- except Exception as e:
- raise IOError("Failed %s: %s" % (msg, e))
+ util.log_time(LOG.debug, msg="Setting up swap file", func=create_swapfile,
+ args=[fname, mibsize])
return fname
diff --git a/tests/unittests/test_handler/test_handler_mounts.py b/tests/unittests/test_handler/test_handler_mounts.py
index 0fb160b..7bcefa0 100644
--- a/tests/unittests/test_handler/test_handler_mounts.py
+++ b/tests/unittests/test_handler/test_handler_mounts.py
@@ -181,6 +181,18 @@ class TestFstabHandling(test_helpers.FilesystemMockingTestCase):
return dev
+ def test_swap_integrity(self):
+ '''Ensure that the swap file is correctly created and can
+ swapon successfully. Fixing the corner case of:
+ kernel: swapon: swapfile has holes'''
+
+ fstab = '/swap.img swap swap defaults 0 0\n'
+
+ with open(cc_mounts.FSTAB_PATH, 'w') as fd:
+ fd.write(fstab)
+ cc = {'swap': ['filename: /swap.img', 'size: 512', 'maxsize: 512']}
+ cc_mounts.handle(None, cc, self.mock_cloud, self.mock_log, [])
+
def test_fstab_no_swap_device(self):
'''Ensure that cloud-init adds a discovered swap partition
to /etc/fstab.'''
--
1.8.3.1