From patchwork Fri Aug 14 16:01:03 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 7016361 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 722C6C05AD for ; Fri, 14 Aug 2015 16:01:41 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9BEFF207F9 for ; Fri, 14 Aug 2015 16:01:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB17D207FB for ; Fri, 14 Aug 2015 16:01:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755518AbbHNQBY (ORCPT ); Fri, 14 Aug 2015 12:01:24 -0400 Received: from www.linutronix.de ([62.245.132.108]:47258 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755424AbbHNQBT (ORCPT ); Fri, 14 Aug 2015 12:01:19 -0400 Received: from localhost ([127.0.0.1] helo=bazinga.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1ZQHPw-0001G0-Mj; Fri, 14 Aug 2015 18:01:16 +0200 From: Sebastian Andrzej Siewior To: peter@hurleysoftware.com Cc: linux-kernel@vger.kernel.org, nsekhar@ti.com, linux-omap@vger.kernel.org, linux-serial@vger.kernel.org, john.ogness@linutronix.de, Sebastian Andrzej Siewior , Greg Kroah-Hartman Subject: [PATCH 2/3] serial: 8250_omap: check how many bytes were injected Date: Fri, 14 Aug 2015 18:01:03 +0200 Message-Id: <1439568064-7907-2-git-send-email-bigeasy@linutronix.de> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1439568064-7907-1-git-send-email-bigeasy@linutronix.de> References: <1439568064-7907-1-git-send-email-bigeasy@linutronix.de> X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001, URIBL_BLOCKED=0.001 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The function tty_insert_flip_string() returns an int and as such it might fail. So the result is that I kindly asked to insert 48 bytes and the function only insterted 32. I have no idea what to do with the remaining 16 so I think dropping them is the only option. I also increase the buf_overrun counter so userpace has a clue that we lost bytes. Cc: Greg Kroah-Hartman Signed-off-by: Sebastian Andrzej Siewior Tested-by: Sekhar Nori --- drivers/tty/serial/8250/8250_omap.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 2ac63c8bd946..933f7ef2c004 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -738,6 +738,7 @@ static void __dma_rx_do_complete(struct uart_8250_port *p, bool error) struct dma_tx_state state; int count; unsigned long flags; + int ret; dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr, dma->rx_size, DMA_FROM_DEVICE); @@ -753,8 +754,10 @@ static void __dma_rx_do_complete(struct uart_8250_port *p, bool error) count = dma->rx_size - state.residue; - tty_insert_flip_string(tty_port, dma->rx_buf, count); - p->port.icount.rx += count; + ret = tty_insert_flip_string(tty_port, dma->rx_buf, count); + + p->port.icount.rx += ret; + p->port.icount.buf_overrun += count - ret; unlock: spin_unlock_irqrestore(&priv->rx_dma_lock, flags);