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Starke" X-Patchwork-Id: 599677 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 EDBA5C32774 for ; Tue, 23 Aug 2022 06:30:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240517AbiHWGaR (ORCPT ); Tue, 23 Aug 2022 02:30:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35892 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240664AbiHWGaO (ORCPT ); Tue, 23 Aug 2022 02:30:14 -0400 X-Greylist: delayed 63 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 22 Aug 2022 23:30:12 PDT Received: from mta-64-228.siemens.flowmailer.net (mta-64-228.siemens.flowmailer.net [185.136.64.228]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 03ED1606A7 for ; Mon, 22 Aug 2022 23:30:12 -0700 (PDT) Received: by mta-64-228.siemens.flowmailer.net with ESMTPSA id 20220823062405382d0f5da0db0e962a for ; Tue, 23 Aug 2022 08:29:07 +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=uMc0cjMZvmQNktk2K16WJyyZXa3z5nE2bVBa+DHfPGM=; b=AJgN3Bt+vn1xGLPrTRHREipJPGLkbPZIs3if1j1W7kBsNBxjt93r9MOFVfmvXEyuI2IACI bkJijDV4h9KfKoctVh0Jyh4mjKnP/JtNwTK6YYTL7d0WvTjD4RVhpdQ1b9ML+SUmcXDWjpeJ Nk9CPJ0tBOac6xOYEuFPTKmxup74Q=; 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 v2 3/6] tty: n_gsm: replace use of gsm_read_ea() with gsm_read_ea_val() Date: Tue, 23 Aug 2022 08:22:56 +0200 Message-Id: <20220823062259.4754-3-daniel.starke@siemens.com> In-Reply-To: <20220823062259.4754-1-daniel.starke@siemens.com> References: <20220823062259.4754-1-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. Reported-by: kernel test robot Signed-off-by: Daniel Starke --- drivers/tty/n_gsm.c | 99 +++++++++++++++++++++++---------------------- 1 file changed, 51 insertions(+), 48 deletions(-) Changes since v1: Fixed use of wrong variable in debug output within gsm_dlci_data(). Link: https://lore.kernel.org/all/202208222147.WfFRmf1r-lkp@intel.com/ diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index ed399d57b197..9535e84f3063 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -1418,18 +1418,13 @@ 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 +1433,21 @@ 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 +1922,10 @@ 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 +1933,22 @@ 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 +1969,29 @@ 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; - } - } + const u8 *dp = data; + int clen = 0; + int dlen; + + /* read the command */ + dlen = gsm_read_ea_val(&command, dp, len); + len -= dlen; + dp += dlen; + + /* read any control data */ + dlen = gsm_read_ea_val(&clen, dp, len); + len -= dlen; + dp += dlen; + + /* Malformed command? */ + if (clen > len) + return; + + if (command & 1) + gsm_control_message(dlci->gsm, command, dp, clen); + else + gsm_control_response(dlci->gsm, command, dp, clen); + return; } /**