From nobody Sun Nov 9 14:51:57 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1550625600583473.5266254518392; Tue, 19 Feb 2019 17:20:00 -0800 (PST) Received: from localhost ([127.0.0.1]:57504 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gwGYE-0003Ya-De for importer@patchew.org; Tue, 19 Feb 2019 20:19:54 -0500 Received: from eggs.gnu.org ([209.51.188.92]:41251) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gwGQP-0005cx-VS for qemu-devel@nongnu.org; Tue, 19 Feb 2019 20:11:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gwGN4-0003r2-PH for qemu-devel@nongnu.org; Tue, 19 Feb 2019 20:08:29 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48588) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gwGMz-0002bE-UI; Tue, 19 Feb 2019 20:08:18 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9E35F5944D; Wed, 20 Feb 2019 01:06:03 +0000 (UTC) Received: from x1w.redhat.com (unknown [10.40.205.222]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 55C561001E7E; Wed, 20 Feb 2019 01:05:51 +0000 (UTC) From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= To: qemu-devel@nongnu.org, Prasad J Pandit , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , Paolo Bonzini Date: Wed, 20 Feb 2019 02:02:19 +0100 Message-Id: <20190220010232.18731-13-philmd@redhat.com> In-Reply-To: <20190220010232.18731-1-philmd@redhat.com> References: <20190220010232.18731-1-philmd@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Wed, 20 Feb 2019 01:06:03 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 12/25] xen: Let buffer_append() return the size consumed X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Corey Minyard , Stefano Stabellini , Samuel Thibault , Li Zhijian , Amit Shah , "Michael S. Tsirkin" , Jason Wang , Cornelia Huck , Halil Pasic , Christian Borntraeger , qemu-s390x@nongnu.org, Paul Durrant , qemu-ppc@nongnu.org, Gerd Hoffmann , Pavel Dovgalyuk , Zhang Chen , Anthony Perard , xen-devel@lists.xenproject.org, Stefan Berger , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , David Gibson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" The buffer.size and buffer.consumed fields are only updated within the buffer_append() body. We can simply let buffer_append() return the difference (the buffer consumed). Signed-off-by: Philippe Mathieu-Daud=C3=A9 --- hw/char/xen_console.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c index 083b2c8e2a..1a30014a11 100644 --- a/hw/char/xen_console.c +++ b/hw/char/xen_console.c @@ -48,7 +48,7 @@ struct XenConsole { int backlog; }; =20 -static void buffer_append(struct XenConsole *con) +static ssize_t buffer_append(struct XenConsole *con) { struct buffer *buffer =3D &con->buffer; XENCONS_RING_IDX cons, prod, size; @@ -59,8 +59,9 @@ static void buffer_append(struct XenConsole *con) xen_mb(); =20 size =3D prod - cons; - if ((size =3D=3D 0) || (size > sizeof(intf->out))) - return; + if ((size =3D=3D 0) || (size > sizeof(intf->out))) { + goto out; + } =20 if ((buffer->capacity - buffer->size) < size) { buffer->capacity +=3D (size + 1024); @@ -89,6 +90,9 @@ static void buffer_append(struct XenConsole *con) if (buffer->consumed > buffer->max_capacity - over) buffer->consumed =3D buffer->max_capacity - over; } + + out: + return buffer->size - buffer->consumed; } =20 static void buffer_advance(struct buffer *buffer, size_t len) @@ -281,8 +285,7 @@ static void con_event(struct XenLegacyDevice *xendev) struct XenConsole *con =3D container_of(xendev, struct XenConsole, xen= dev); ssize_t size; =20 - buffer_append(con); - size =3D con->buffer.size - con->buffer.consumed; + size =3D buffer_append(con); if (size) { xencons_send(con, size); } --=20 2.20.1