From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755710AbbKDLqo (ORCPT ); Wed, 4 Nov 2015 06:46:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:33461 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752292AbbKDLqm (ORCPT ); Wed, 4 Nov 2015 06:46:42 -0500 Subject: Re: [PATCH v2 3/3] ibmvscsi: Allow to configure maximum LUN To: Hannes Reinecke , martin.petersen@oracle.com References: <1446632451-22365-1-git-send-email-lvivier@redhat.com> <1446632451-22365-4-git-send-email-lvivier@redhat.com> <5639E904.1070100@suse.de> Cc: brking@linux.vnet.ibm.com, tyreld@linux.vnet.ibm.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org From: Laurent Vivier Message-ID: <5639F020.4010308@redhat.com> Date: Wed, 4 Nov 2015 12:46:40 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <5639E904.1070100@suse.de> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/11/2015 12:16, Hannes Reinecke wrote: > On 11/04/2015 11:20 AM, Laurent Vivier wrote: >> QEMU allows until 32 LUNs. >> >> Signed-off-by: Laurent Vivier >> --- >> drivers/scsi/ibmvscsi/ibmvscsi.c | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c >> index 04de287..4480d3e 100644 >> --- a/drivers/scsi/ibmvscsi/ibmvscsi.c >> +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c >> @@ -84,6 +84,7 @@ >> */ >> static int max_id = 64; >> static int max_channel = 3; >> +static int max_lun = 8; >> static int init_timeout = 300; >> static int login_timeout = 60; >> static int info_timeout = 30; >> @@ -117,6 +118,8 @@ module_param_named(fast_fail, fast_fail, int, S_IRUGO | S_IWUSR); >> MODULE_PARM_DESC(fast_fail, "Enable fast fail. [Default=1]"); >> module_param_named(client_reserve, client_reserve, int, S_IRUGO ); >> MODULE_PARM_DESC(client_reserve, "Attempt client managed reserve/release"); >> +module_param(max_lun, int, S_IRUGO); >> +MODULE_PARM_DESC(max_lun, "Maximum LUN value [Default=8]"); >> >> static void ibmvscsi_handle_crq(struct viosrp_crq *crq, >> struct ibmvscsi_host_data *hostdata); >> @@ -2289,7 +2292,7 @@ static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id) >> goto init_pool_failed; >> } >> >> - host->max_lun = 8; >> + host->max_lun = max_lun; >> host->max_id = max_id; >> host->max_channel = max_channel; >> host->max_cmd_len = 16; >> > Please, don't do this. > > 'max_lun' should only be set if the HBA / transport has some hard > limitations on the number of bytes it can use. > Otherwise the scanning algorithm in scsi_scan.c should do the > correct thing, independent on the 'max_lun' setting. So you are saying we can remove the line ? > If qemu has some issues here someone should rather fix qemu ... There is no issue with QEMU. QEMU can manage more than "8" LUNs, and we'd like to. Laurent