NFSv4.2: Serialise O_DIRECT i/o and clone range

Ensure that all O_DIRECT reads and writes complete before cloning a file
range, so that both the source and destination are up to date.

Fixes: a5864c999de6 ("NFS: Do not serialise O_DIRECT reads and writes")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 1d6b5f4230c9b2857ae216c531079feccb669538..c9a0d1e420c6cb17b209e3f7f48a12dd479dbc24 100644 (file)
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -278,9 +278,11 @@ static loff_t nfs42_remap_file_range(struct file *src_file, loff_t src_off,
        lock_two_nondirectories(src_inode, dst_inode);
        /* flush all pending writes on both src and dst so that server
         * has the latest data */
+       nfs_file_block_o_direct(NFS_I(src_inode));
        ret = nfs_sync_inode(src_inode);
        if (ret)
                goto out_unlock;
+       nfs_file_block_o_direct(NFS_I(dst_inode));
        ret = nfs_sync_inode(dst_inode);
        if (ret)
                goto out_unlock;