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=ham 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 C04EEC433DF for ; Thu, 18 Jun 2020 02:40:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9B37B21D7A for ; Thu, 18 Jun 2020 02:40:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592448049; bh=JD6VulhTF5DpJPPlLu8INgo7BX5Vmjr1ot6kY9qqoOE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Pivp2/7Wb2ywzYgbz6+xQ3wDbSEStCkseq/qxfOzRQVyjeOpRJ/XpfHQ9jwHVBXsI H6makfZSFafvME9sKAFBVX/bkB+AKkmhc8v+QgEqs5tx4xFYuciFFWgros6y1o+mOh nt6eNLzGwWJIJ+qec/polNdGcuzR8zpOJTLf4F1w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729564AbgFRCkr (ORCPT ); Wed, 17 Jun 2020 22:40:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:41322 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728936AbgFRBMg (ORCPT ); Wed, 17 Jun 2020 21:12:36 -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 EAD0520EDD; Thu, 18 Jun 2020 01:12:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592442756; bh=JD6VulhTF5DpJPPlLu8INgo7BX5Vmjr1ot6kY9qqoOE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gtGinvZ/QecNfTtaWP3EB7ltwq6ndig6iaK557qm6x9R1U5GzyrFyRXN9pFfHluac oVxkoo/giOJ4szuCaKd/9RtOX7adaXNC52gwxYNfGrYqZqFuVvG4OUyATZcmShDBVo 6jbbV2DI+dk0HaXrgtBinoP9cqdL1JeA2JulGL90= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Gregory CLEMENT , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 5.7 207/388] tty: n_gsm: Fix waking up upper tty layer when room available Date: Wed, 17 Jun 2020 21:05:04 -0400 Message-Id: <20200618010805.600873-207-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200618010805.600873-1-sashal@kernel.org> References: <20200618010805.600873-1-sashal@kernel.org> MIME-Version: 1.0 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 20b22c55547e..0a8f241e537d 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -673,7 +673,7 @@ 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; @@ -705,6 +705,24 @@ 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); + } + } } } @@ -756,7 +774,7 @@ 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); } /** @@ -1217,7 +1235,7 @@ 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: @@ -2539,7 +2557,7 @@ 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