From patchwork Tue Mar 27 16:41:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 891699 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 409cHs49Xjz9s1q for ; Wed, 28 Mar 2018 03:42:32 +1100 (AEDT) Received: from localhost ([::1]:35251 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f0rg4-0001R5-6J for incoming@patchwork.ozlabs.org; Tue, 27 Mar 2018 12:42:28 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53264) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f0rfb-0001QW-Nv for qemu-devel@nongnu.org; Tue, 27 Mar 2018 12:42:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f0rfY-0002pO-C4 for qemu-devel@nongnu.org; Tue, 27 Mar 2018 12:41:59 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:36786 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f0rfY-0002pD-7O for qemu-devel@nongnu.org; Tue, 27 Mar 2018 12:41:56 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BFF59F6404; Tue, 27 Mar 2018 16:41:52 +0000 (UTC) Received: from lemon.usersys.redhat.com (ovpn-12-44.pek2.redhat.com [10.72.12.44]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4E224215CDB5; Tue, 27 Mar 2018 16:41:46 +0000 (UTC) From: Fam Zheng To: qemu-devel@nongnu.org Date: Wed, 28 Mar 2018 00:41:41 +0800 Message-Id: <20180327164141.19075-1-famz@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Tue, 27 Mar 2018 16:41:52 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Tue, 27 Mar 2018 16:41:52 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'famz@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v2] scsi-disk: Don't enlarge min_io_size to max_io_size 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: danielhb@linux.vnet.ibm.com, Paolo Bonzini , Fam Zheng , dgibson@redhat.com Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" Some backends report big max_io_sectors. Making min_io_size the same value in this case will make it impossible for guest to align memory, therefore the disk may not be usable at all. Do not enlarge them when they are zero. Reported-by: David Gibson Signed-off-by: Fam Zheng Reviewed-by: Daniel Henrique Barboza Tested-by: David Gibson --- v2: Leave the values alone if zero. [Paolo] At least we can consult block layer for a slightly more sensible opt_io_size, but that's for another patch. --- hw/scsi/scsi-disk.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index f5ab767ab5..f8ed8cf2b4 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -714,10 +714,12 @@ static int scsi_disk_emulate_inquiry(SCSIRequest *req, uint8_t *outbuf) /* min_io_size and opt_io_size can't be greater than * max_io_sectors */ - min_io_size = - MIN_NON_ZERO(min_io_size, max_io_sectors); - opt_io_size = - MIN_NON_ZERO(opt_io_size, max_io_sectors); + if (min_io_size) { + min_io_size = MIN(min_io_size, max_io_sectors); + } + if (opt_io_size) { + opt_io_size = MIN(opt_io_size, max_io_sectors); + } } /* required VPD size with unmap support */ buflen = 0x40;