CIFS: Do not consider -ENODATA as stat failure for reads

commit 082aaa8700415f6471ec9c5ef0c8307ca214989a upstream.

When doing reads beyound the end of a file the server returns
error STATUS_END_OF_FILE error which is mapped to -ENODATA.
Currently we report it as a failure which confuses read stats.
Change it to not consider -ENODATA as failure for stat purposes.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/cifs/smb2pdu.c

@@ -3127,7 +3127,7 @@ smb2_readv_callback(struct mid_q_entry *mid)
 		rdata->mr = NULL;
 	}
 #endif
-	if (rdata->result) {
+	if (rdata->result && rdata->result != -ENODATA) {
 		cifs_stats_fail_inc(tcon, SMB2_READ_HE);
 		trace_smb3_read_err(0 /* xid */,
 				    rdata->cfile->fid.persistent_fid,