queue-4.4/ceph-flush-dirty-inodes-before-proceeding-with-remount.patch

   1 From 00abf69dd24f4444d185982379c5cc3bb7b6d1fc Mon Sep 17 00:00:00 2001
   2 From: Jeff Layton <jlayton@kernel.org>
   3 Date: Tue, 7 May 2019 09:20:54 -0400
   4 Subject: ceph: flush dirty inodes before proceeding with remount
   5
   6 From: Jeff Layton <jlayton@kernel.org>
   7
   8 commit 00abf69dd24f4444d185982379c5cc3bb7b6d1fc upstream.
   9
  10 xfstest generic/452 was triggering a "Busy inodes after umount" warning.
  11 ceph was allowing the mount to go read-only without first flushing out
  12 dirty inodes in the cache. Ensure we sync out the filesystem before
  13 allowing a remount to proceed.
  14
  15 Cc: stable@vger.kernel.org
  16 Link: http://tracker.ceph.com/issues/39571
  17 Signed-off-by: Jeff Layton <jlayton@kernel.org>
  18 Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
  19 Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
  20 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  21
  22 ---
  23  fs/ceph/super.c |    7 +++++++
  24  1 file changed, 7 insertions(+)
  25
  26 --- a/fs/ceph/super.c
  27 +++ b/fs/ceph/super.c
  28 @@ -712,6 +712,12 @@ static void ceph_umount_begin(struct sup
  29         return;
  30  }
  31
  32 +static int ceph_remount(struct super_block *sb, int *flags, char *data)
  33 +{
  34 +       sync_filesystem(sb);
  35 +       return 0;
  36 +}
  37 +
  38  static const struct super_operations ceph_super_ops = {
  39         .alloc_inode    = ceph_alloc_inode,
  40         .destroy_inode  = ceph_destroy_inode,
  41 @@ -719,6 +725,7 @@ static const struct super_operations cep
  42         .drop_inode     = ceph_drop_inode,
  43         .sync_fs        = ceph_sync_fs,
  44         .put_super      = ceph_put_super,
  45 +       .remount_fs     = ceph_remount,
  46         .show_options   = ceph_show_options,
  47         .statfs         = ceph_statfs,
  48         .umount_begin   = ceph_umount_begin,