queue-4.19/fs-fat-file.c-issue-flush-after-the-writeback-of-fat.patch

   1 From 78bbcc38db4efba1f64fbf8351bec5583c1132e1 Mon Sep 17 00:00:00 2001
   2 From: Hou Tao <houtao1@huawei.com>
   3 Date: Tue, 14 May 2019 15:44:32 -0700
   4 Subject: fs/fat/file.c: issue flush after the writeback of FAT
   5
   6 [ Upstream commit bd8309de0d60838eef6fb575b0c4c7e95841cf73 ]
   7
   8 fsync() needs to make sure the data & meta-data of file are persistent
   9 after the return of fsync(), even when a power-failure occurs later.  In
  10 the case of fat-fs, the FAT belongs to the meta-data of file, so we need
  11 to issue a flush after the writeback of FAT instead before.
  12
  13 Also bail out early when any stage of fsync fails.
  14
  15 Link: http://lkml.kernel.org/r/20190409030158.136316-1-houtao1@huawei.com
  16 Signed-off-by: Hou Tao <houtao1@huawei.com>
  17 Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
  18 Cc: Al Viro <viro@zeniv.linux.org.uk>
  19 Cc: Jan Kara <jack@suse.cz>
  20 Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
  21 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
  22 Signed-off-by: Sasha Levin <sashal@kernel.org>
  23 ---
  24  fs/fat/file.c | 11 ++++++++---
  25  1 file changed, 8 insertions(+), 3 deletions(-)
  26
  27 diff --git a/fs/fat/file.c b/fs/fat/file.c
  28 index 4f3d72fb1e60..f86ea08bd6ce 100644
  29 --- a/fs/fat/file.c
  30 +++ b/fs/fat/file.c
  31 @@ -193,12 +193,17 @@ static int fat_file_release(struct inode *inode, struct file *filp)
  32  int fat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
  33  {
  34         struct inode *inode = filp->f_mapping->host;
  35 -       int res, err;
  36 +       int err;
  37 +
  38 +       err = __generic_file_fsync(filp, start, end, datasync);
  39 +       if (err)
  40 +               return err;
  41
  42 -       res = generic_file_fsync(filp, start, end, datasync);
  43         err = sync_mapping_buffers(MSDOS_SB(inode->i_sb)->fat_inode->i_mapping);
  44 +       if (err)
  45 +               return err;
  46
  47 -       return res ? res : err;
  48 +       return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
  49  }
  50
  51
  52 --
  53 2.20.1
  54