respect-nobarrier-mount-option-in-nojournal-mode

   1 ext4: respect the nobarrier mount option in nojournal mode
   2
   3 Also, if we are going to issue the barrier, we should do this after we
   4 write out the parent directories if necessary.
   5
   6 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
   7 Reviewed-by: Jan Kara <jack@suse.cz>
   8 ---
   9  fs/ext4/fsync.c | 5 ++++-
  10  1 file changed, 4 insertions(+), 1 deletion(-)
  11
  12 diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
  13 index 8850254..5c43725 100644
  14 --- a/fs/ext4/fsync.c
  15 +++ b/fs/ext4/fsync.c
  16 @@ -106,9 +106,11 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
  17         }
  18
  19         if (!journal) {
  20 -               ret = generic_file_fsync(file, start, end, datasync);
  21 +               ret = __generic_file_fsync(file, start, end, datasync);
  22                 if (!ret && !hlist_empty(&inode->i_dentry))
  23                         ret = ext4_sync_parent(inode);
  24 +               if (test_opt(inode->i_sb, BARRIER))
  25 +                       goto issue_flush;
  26                 goto out;
  27         }
  28
  29 @@ -140,6 +142,7 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
  30                 needs_barrier = true;
  31         ret = jbd2_complete_transaction(journal, commit_tid);
  32         if (needs_barrier) {
  33 +       issue_flush:
  34                 err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
  35                 if (!ret)
  36                         ret = err;