From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10808C433DF for ; Mon, 29 Jun 2020 21:11:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DCFDC206A1 for ; Mon, 29 Jun 2020 21:11:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593465077; bh=/sxvIWXyWXMgUn+hUmKJH6X+uguGxYiWi7hE7loHJZ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rjXeZAVIUWrIx8FqXljeI6N462eumI9KLXefH13cNZ9fwOApdYN6KnGdgjwtPkb8O 0bbE9yo0wsp7VFgAMCnk9r3hnxKjPrD9k/JRypBbumnEpMpbn0HPdoYNILvgv6TFMJ vC8qrzy8unFq0HtJWyutcNfNnE74TcjyX5Am+7dg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390396AbgF2VLP (ORCPT ); Mon, 29 Jun 2020 17:11:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:45394 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730301AbgF2TAP (ORCPT ); Mon, 29 Jun 2020 15:00:15 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9338B254CF; Mon, 29 Jun 2020 15:53:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593446026; bh=/sxvIWXyWXMgUn+hUmKJH6X+uguGxYiWi7hE7loHJZ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Zpe+dYE1iPQQ61dRld04IuuL1e3v5dnpXKaGdgJQ40oTvO8G69bhhcDev1QxsZu9n 2uOLAd+QhmO76KcUjSS47QXxY5+LoDQHNQTlw8n8JXlzKi7/1CF6cc3+dKhI/i2Cd5 oa+sVyJspTkCDKnro99WXKBl8AO75nTL+q4dprNo= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Gregory CLEMENT , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 4.4 032/135] tty: n_gsm: Fix waking up upper tty layer when room available Date: Mon, 29 Jun 2020 11:51:26 -0400 Message-Id: <20200629155309.2495516-33-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200629155309.2495516-1-sashal@kernel.org> References: <20200629155309.2495516-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.4.229-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-4.4.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 4.4.229-rc1 X-KernelTest-Deadline: 2020-07-01T15:53+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Gregory CLEMENT [ Upstream commit 01dbb362f0a114fbce19c8abe4cd6f4710e934d5 ] Warn the upper layer when n_gms is ready to receive data again. Without this the associated virtual tty remains blocked indefinitely. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Gregory CLEMENT Link: https://lore.kernel.org/r/20200512115323.1447922-4-gregory.clement@bootlin.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/n_gsm.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 08aaf993221e7..0020de4fe66f5 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -681,7 +681,7 @@ static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len, * FIXME: lock against link layer control transmissions */ -static void gsm_data_kick(struct gsm_mux *gsm) +static void gsm_data_kick(struct gsm_mux *gsm, struct gsm_dlci *dlci) { struct gsm_msg *msg, *nmsg; int len; @@ -713,6 +713,24 @@ static void gsm_data_kick(struct gsm_mux *gsm) list_del(&msg->list); kfree(msg); + + if (dlci) { + tty_port_tty_wakeup(&dlci->port); + } else { + int i = 0; + + for (i = 0; i < NUM_DLCI; i++) { + struct gsm_dlci *dlci; + + dlci = gsm->dlci[i]; + if (dlci == NULL) { + i++; + continue; + } + + tty_port_tty_wakeup(&dlci->port); + } + } } } @@ -764,7 +782,7 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg) /* Add to the actual output queue */ list_add_tail(&msg->list, &gsm->tx_list); gsm->tx_bytes += msg->len; - gsm_data_kick(gsm); + gsm_data_kick(gsm, dlci); } /** @@ -1225,7 +1243,7 @@ static void gsm_control_message(struct gsm_mux *gsm, unsigned int command, gsm_control_reply(gsm, CMD_FCON, NULL, 0); /* Kick the link in case it is idling */ spin_lock_irqsave(&gsm->tx_lock, flags); - gsm_data_kick(gsm); + gsm_data_kick(gsm, NULL); spin_unlock_irqrestore(&gsm->tx_lock, flags); break; case CMD_FCOFF: @@ -2423,7 +2441,7 @@ static void gsmld_write_wakeup(struct tty_struct *tty) /* Queue poll */ clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); spin_lock_irqsave(&gsm->tx_lock, flags); - gsm_data_kick(gsm); + gsm_data_kick(gsm, NULL); if (gsm->tx_bytes < TX_THRESH_LO) { gsm_dlci_data_sweep(gsm); } -- 2.25.1