Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751822AbbKIO7o (ORCPT ); Mon, 9 Nov 2015 09:59:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40791 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750855AbbKIO7n (ORCPT ); Mon, 9 Nov 2015 09:59:43 -0500 Subject: Re: [PATCH v4 3/3] ibmvscsi: Allow to configure maximum LUN To: Hannes Reinecke References: <1447080465-17858-1-git-send-email-lvivier@redhat.com> <1447080465-17858-4-git-send-email-lvivier@redhat.com> <5640B2A6.20401@suse.de> Cc: martin.petersen@oracle.com, 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: <5640B4DC.9010706@redhat.com> Date: Mon, 9 Nov 2015 15:59:40 +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: <5640B2A6.20401@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 Content-Length: 3658 Lines: 96 On 09/11/2015 15:50, Hannes Reinecke wrote: > On 11/09/2015 03:47 PM, Laurent Vivier wrote: >> This patch allows to define the maximum LUN numbers. >> As defined in 4.6.9 of SAM-4, the encoding of LUN is >> on 5 bits (max_lun=32) and the current value is only 8. >> >> Signed-off-by: Laurent Vivier >> --- >> drivers/scsi/ibmvscsi/ibmvscsi.c | 9 ++++++++- >> drivers/scsi/ibmvscsi/ibmvscsi.h | 1 + >> 2 files changed, 9 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c >> index 04de287..adcd5e8 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 +118,9 @@ 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 allowed LUN " >> + "[Default=8,Max="__stringify(IBMVSCSI_MAX_LUN)"]"); >> >> static void ibmvscsi_handle_crq(struct viosrp_crq *crq, >> struct ibmvscsi_host_data *hostdata); >> @@ -2289,7 +2293,7 @@ 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; >> @@ -2414,6 +2418,9 @@ int __init ibmvscsi_module_init(void) >> { >> int ret; >> >> + if (max_lun > IBMVSCSI_MAX_LUN) >> + return -EINVAL; >> + >> /* Ensure we have two requests to do error recovery */ >> driver_template.can_queue = max_requests; >> max_events = max_requests + 2; >> diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.h b/drivers/scsi/ibmvscsi/ibmvscsi.h >> index 7d64867..1067367 100644 >> --- a/drivers/scsi/ibmvscsi/ibmvscsi.h >> +++ b/drivers/scsi/ibmvscsi/ibmvscsi.h >> @@ -48,6 +48,7 @@ struct Scsi_Host; >> #define IBMVSCSI_CMDS_PER_LUN_DEFAULT 16 >> #define IBMVSCSI_MAX_SECTORS_DEFAULT 256 /* 32 * 8 = default max I/O 32 pages */ >> #define IBMVSCSI_MAX_CMDS_PER_LUN 64 >> +#define IBMVSCSI_MAX_LUN 32 >> >> /* ------------------------------------------------------------ >> * Data Structures >> > Please set max_lun to 31, and remove everything else. > As discussed, max_lun is the max number of LUNs supported by the > hardware/HBA. There is no point in restricting it further. You mean no module parameter and a simple "host->max_lun = 31" ? I'm wondering if it should be "host->max_lun = 32". What about this ? include/scsi/scsi_host.h: /* * These three parameters can be used to allow for wide scsi, * and for host adapters that support multiple busses * The last two should be set to 1 more than the actual max id * or lun (e.g. 8 for SCSI parallel systems). */ unsigned int max_channel; unsigned int max_id; u64 max_lun; As ibmvscsi maximum LUN value is 31, host->max_lun should be 32. Laurent -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/