From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin K. Petersen" Subject: Re: [PATCH v2] mpt3sas: Force request partial completion alignment Date: Wed, 25 Jan 2017 18:46:13 -0500 Message-ID: References: <1485272838-23180-1-git-send-email-gpiccoli@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from userp1040.oracle.com ([156.151.31.81]:38012 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750877AbdAYXqW (ORCPT ); Wed, 25 Jan 2017 18:46:22 -0500 In-Reply-To: <1485272838-23180-1-git-send-email-gpiccoli@linux.vnet.ibm.com> (Guilherme G. Piccoli's message of "Tue, 24 Jan 2017 13:47:18 -0200") Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: "Guilherme G. Piccoli" Cc: linux-scsi@vger.kernel.org, MPT-FusionLinux.pdl@broadcom.com, sathya.prakash@broadcom.com, chaitra.basappa@broadcom.com, suganath-prabu.subramani@broadcom.com, sreekanth.reddy@broadcom.com, brking@linux.vnet.ibm.com, mauricfo@linux.vnet.ibm.com, linuxram@us.ibm.com >>>>> "Guilherme" == Guilherme G Piccoli writes: Hi Guilherme, diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c index 75f3fce..e52c942 100644 --- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c +++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c @@ -4657,6 +4657,8 @@ _scsih_io_done(struct MPT3SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply) struct MPT3SAS_DEVICE *sas_device_priv_data; u32 response_code = 0; unsigned long flags; + unsigned int sector_sz; + struct request *req; mpi_reply = mpt3sas_base_get_reply_virt_addr(ioc, reply); scmd = _scsih_scsi_lookup_get_clear(ioc, smid); @@ -4715,6 +4717,21 @@ _scsih_io_done(struct MPT3SAS_ADAPTER *ioc, u16 smid, u8 msix_index, u32 reply) } xfer_cnt = le32_to_cpu(mpi_reply->TransferCount); + + /* In case of bogus fw or device, we could end up having + * unaligned partial completion. We can force alignment here, + * then scsi-ml does not need to handle this misbehavior. + */ + sector_sz = scmd->device->sector_size; + req = scmd->request; + if (unlikely(sector_sz && req && (req->cmd_type == REQ_TYPE_FS) && + (xfer_cnt % sector_sz))) { Maybe a bit zealous on the sanity checking... + sdev_printk(KERN_INFO, scmd->device, + "unaligned partial completion avoided (xfer_cnt=%u, sector_sz=%u)\n", + xfer_cnt, sector_sz); + xfer_cnt = (xfer_cnt / sector_sz) * sector_sz; Not so keen on divisions. xfer_cnt = round_down(xfer_cnt, sector_sz), maybe? -- Martin K. Petersen Oracle Linux Engineering