Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753775AbdC3Cho (ORCPT ); Wed, 29 Mar 2017 22:37:44 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:27440 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751941AbdC3Chm (ORCPT ); Wed, 29 Mar 2017 22:37:42 -0400 To: Fam Zheng Cc: linux-kernel@vger.kernel.org, "Martin K. Petersen" , linux-scsi@vger.kernel.org, Laurence Oberman , "James E.J. Bottomley" Subject: Re: [PATCH v2] sd: Consider max_xfer_blocks if opt_xfer_blocks is unusable From: "Martin K. Petersen" Organization: Oracle Corporation References: <20170328044126.10006-1-famz@redhat.com> Date: Wed, 29 Mar 2017 22:37:34 -0400 In-Reply-To: <20170328044126.10006-1-famz@redhat.com> (Fam Zheng's message of "Tue, 28 Mar 2017 12:41:26 +0800") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 759 Lines: 27 Fam Zheng writes: Fam, > diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c > index fcfeddc..a5c7e67 100644 > --- a/drivers/scsi/sd.c > +++ b/drivers/scsi/sd.c > @@ -2957,6 +2957,7 @@ static int sd_revalidate_disk(struct gendisk *disk) > rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks); > } else > rw_max = BLK_DEF_MAX_SECTORS; > + rw_max = min_not_zero(rw_max, logical_to_sectors(sdp, dev_max)); > > /* Combine with controller limits */ > q->limits.max_sectors = min(rw_max, queue_max_hw_sectors(q)); Instead of updating rw_max twice, how about: } else rw_max = min_not_zero(logical_to_sectors(sdp, dev_max), BLK_DEF_MAX_SECTORS); ? -- Martin K. Petersen Oracle Linux Engineering