From patchwork Wed Aug 31 07:37:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "D. Starke" X-Patchwork-Id: 602726 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C318ECAAD3 for ; Wed, 31 Aug 2022 08:12:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231193AbiHaIM3 (ORCPT ); Wed, 31 Aug 2022 04:12:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231138AbiHaIM2 (ORCPT ); Wed, 31 Aug 2022 04:12:28 -0400 X-Greylist: delayed 1982 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 31 Aug 2022 01:12:26 PDT Received: from mta-64-227.siemens.flowmailer.net (mta-64-227.siemens.flowmailer.net [185.136.64.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 028CABD153 for ; Wed, 31 Aug 2022 01:12:26 -0700 (PDT) Received: by mta-64-227.siemens.flowmailer.net with ESMTPSA id 2022083107392249f0c1a835796e5d17 for ; Wed, 31 Aug 2022 09:39:22 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm1; d=siemens.com; i=daniel.starke@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc:References:In-Reply-To; bh=TwIIUMEHZdOxYl7FduVtOaXairhIpMTbrbsyZhhePic=; b=PNGDnB4fO35e0NTJ6V2Zo0uCubCjVbATav+8AyVKeGTXIBfCAwq+Sr+WIfE7GdBem1xewA yuD8onJrT6cMY0f6t+IOAQm7TI8K8AWZhKoT2OvaWmF2e/jNbtTwO8/1lLkOntpVQuRCUoBT J5o6Vg67NPidPjkbR9wMW3E2VEEy0=; From: "D. Starke" To: linux-serial@vger.kernel.org, gregkh@linuxfoundation.org, jirislaby@kernel.org Cc: linux-kernel@vger.kernel.org, Daniel Starke , kernel test robot Subject: [PATCH v3 3/6] tty: n_gsm: replace use of gsm_read_ea() with gsm_read_ea_val() Date: Wed, 31 Aug 2022 09:37:57 +0200 Message-Id: <20220831073800.7459-3-daniel.starke@siemens.com> In-Reply-To: <20220831073800.7459-1-daniel.starke@siemens.com> References: <20220831073800.7459-1-daniel.starke@siemens.com> MIME-Version: 1.0 X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-314044:519-21489:flowmailer Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org From: Daniel Starke Replace the use of gsm_read_ea() with gsm_read_ea_val() where applicable to improve code readability and avoid errors like in the past. See first link below for reference. Link: https://lore.kernel.org/all/20220504081733.3494-1-daniel.starke@siemens.com/ Link: https://lore.kernel.org/all/202208222147.WfFRmf1r-lkp@intel.com/ Reported-by: kernel test robot Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 95 ++++++++++++++++++++++----------------------- 1 file changed, 47 insertions(+), 48 deletions(-) Incorporated review comments from Jiri Slaby since v2: - added link to test robot report - added link to previously fixed error - removed extra line-feeds in gsm_control_modem() - removed unnecessary use of dp in gsm_dlci_command() - changed clen and dlen to unsigned int in gsm_dlci_command() - removed extra return in gsm_dlci_command() Link: https://lore.kernel.org/all/387a0d37-6a75-d721-87dd-86219f61ef86@kernel.org/ diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 813363825e54..9d0b4f79b65a 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -1418,18 +1418,12 @@ static void gsm_control_modem(struct gsm_mux *gsm, const u8 *data, int clen) unsigned int modem = 0; struct gsm_dlci *dlci; int len = clen; - int slen; + int cl = clen; const u8 *dp = data; struct tty_struct *tty; - while (gsm_read_ea(&addr, *dp++) == 0) { - len--; - if (len == 0) - return; - } - /* Must be at least one byte following the EA */ - len--; - if (len <= 0) + len = gsm_read_ea_val(&addr, data, cl); + if (len < 1) return; addr >>= 1; @@ -1438,15 +1432,20 @@ static void gsm_control_modem(struct gsm_mux *gsm, const u8 *data, int clen) return; dlci = gsm->dlci[addr]; - slen = len; - while (gsm_read_ea(&modem, *dp++) == 0) { - len--; - if (len == 0) - return; - } - len--; + /* Must be at least one byte following the EA */ + if ((cl - len) < 1) + return; + + dp += len; + cl -= len; + + /* get the modem status */ + len = gsm_read_ea_val(&modem, dp, cl); + if (len < 1) + return; + tty = tty_port_tty_get(&dlci->port); - gsm_process_modem(tty, dlci, modem, slen - len); + gsm_process_modem(tty, dlci, modem, cl); if (tty) { tty_wakeup(tty); tty_kref_put(tty); @@ -1921,11 +1920,10 @@ static void gsm_dlci_data(struct gsm_dlci *dlci, const u8 *data, int clen) struct tty_port *port = &dlci->port; struct tty_struct *tty; unsigned int modem = 0; - int len = clen; - int slen = 0; + int len; if (debug & 16) - pr_debug("%d bytes for tty\n", len); + pr_debug("%d bytes for tty\n", clen); switch (dlci->adaption) { /* Unsupported types */ case 4: /* Packetised interruptible data */ @@ -1933,24 +1931,22 @@ static void gsm_dlci_data(struct gsm_dlci *dlci, const u8 *data, int clen) case 3: /* Packetised uininterruptible voice/data */ break; case 2: /* Asynchronous serial with line state in each frame */ - while (gsm_read_ea(&modem, *data++) == 0) { - len--; - slen++; - if (len == 0) - return; - } - len--; - slen++; + len = gsm_read_ea_val(&modem, data, clen); + if (len < 1) + return; tty = tty_port_tty_get(port); if (tty) { - gsm_process_modem(tty, dlci, modem, slen); + gsm_process_modem(tty, dlci, modem, len); tty_wakeup(tty); tty_kref_put(tty); } + /* Skip processed modem data */ + data += len; + clen -= len; fallthrough; case 1: /* Line state will go via DLCI 0 controls only */ default: - tty_insert_flip_string(port, data, len); + tty_insert_flip_string(port, data, clen); tty_flip_buffer_push(port); } } @@ -1971,24 +1967,27 @@ static void gsm_dlci_command(struct gsm_dlci *dlci, const u8 *data, int len) { /* See what command is involved */ unsigned int command = 0; - while (len-- > 0) { - if (gsm_read_ea(&command, *data++) == 1) { - int clen = *data++; - len--; - /* FIXME: this is properly an EA */ - clen >>= 1; - /* Malformed command ? */ - if (clen > len) - return; - if (command & 1) - gsm_control_message(dlci->gsm, command, - data, clen); - else - gsm_control_response(dlci->gsm, command, - data, clen); - return; - } - } + unsigned int clen = 0; + unsigned int dlen; + + /* read the command */ + dlen = gsm_read_ea_val(&command, data, len); + len -= dlen; + data += dlen; + + /* read any control data */ + dlen = gsm_read_ea_val(&clen, data, len); + len -= dlen; + data += dlen; + + /* Malformed command? */ + if (clen > len) + return; + + if (command & 1) + gsm_control_message(dlci->gsm, command, data, clen); + else + gsm_control_response(dlci->gsm, command, data, clen); } /**