From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Guilherme G. Piccoli" Subject: [PATCH v3] mpt3sas: Force request partial completion alignment Date: Thu, 26 Jan 2017 16:37:01 -0200 Message-ID: <1485455821-9176-1-git-send-email-gpiccoli@linux.vnet.ibm.com> Return-path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:44905 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751957AbdAZShZ (ORCPT ); Thu, 26 Jan 2017 13:37:25 -0500 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v0QIY98r105733 for ; Thu, 26 Jan 2017 13:37:16 -0500 Received: from e24smtp04.br.ibm.com (e24smtp04.br.ibm.com [32.104.18.25]) by mx0a-001b2d01.pphosted.com with ESMTP id 287jhkbe2r-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 26 Jan 2017 13:37:16 -0500 Received: from localhost by e24smtp04.br.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 26 Jan 2017 16:37:13 -0200 Received: from d24relay03.br.ibm.com (d24relay03.br.ibm.com [9.18.232.225]) by d24dlp02.br.ibm.com (Postfix) with ESMTP id 97B8F1DC006E for ; Thu, 26 Jan 2017 13:37:10 -0500 (EST) Received: from d24av03.br.ibm.com (d24av03.br.ibm.com [9.8.31.95]) by d24relay03.br.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v0QIb9JH40763590 for ; Thu, 26 Jan 2017 16:37:09 -0200 Received: from d24av03.br.ibm.com (localhost [127.0.0.1]) by d24av03.br.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v0QIb9WR006875 for ; Thu, 26 Jan 2017 16:37:10 -0200 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org, MPT-FusionLinux.pdl@broadcom.com Cc: sathya.prakash@broadcom.com, chaitra.basappa@broadcom.com, suganath-prabu.subramani@broadcom.com, brking@linux.vnet.ibm.com, gpiccoli@linux.vnet.ibm.com, mauricfo@linux.vnet.ibm.com, linuxram@us.ibm.com, martin.petersen@oracle.com From: Ram Pai The firmware or device, possibly under a heavy I/O load, can return on a partial unaligned boundary. Scsi-ml expects these requests to be completed on an alignment boundary. Scsi-ml blindly requeues the I/O without checking the alignment boundary of the I/O request for the remaining bytes. This leads to errors, since devices cannot perform non-aligned read/write operations. This patch fixes the issue in the driver. It aligns unaligned completions of FS requests, by truncating them to the nearest alignment boundary. Reported-by: Mauricio Faria De Oliveira Signed-off-by: Guilherme G. Piccoli Signed-off-by: Ram Pai Acked-by: Sreekanth Reddy --- v2->v3: * Changed division to round_down() [suggestion by Martin]. drivers/scsi/mpt3sas/mpt3sas_scsih.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c index 75f3fce..a6b6f58 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))) { + sdev_printk(KERN_INFO, scmd->device, + "unaligned partial completion avoided (xfer_cnt=%u, sector_sz=%u)\n", + xfer_cnt, sector_sz); + xfer_cnt = round_down(xfer_cnt, sector_sz); + } + scsi_set_resid(scmd, scsi_bufflen(scmd) - xfer_cnt); if (ioc_status & MPI2_IOCSTATUS_FLAG_LOG_INFO_AVAILABLE) log_info = le32_to_cpu(mpi_reply->IOCLogInfo); -- 2.1.0