From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Guilherme G. Piccoli" Subject: [PATCH v2] mpt3sas: Force request partial completion alignment Date: Tue, 24 Jan 2017 13:47:18 -0200 Message-ID: <1485272838-23180-1-git-send-email-gpiccoli@linux.vnet.ibm.com> Return-path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:40922 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750714AbdAXPrg (ORCPT ); Tue, 24 Jan 2017 10:47:36 -0500 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v0OFOfDo013999 for ; Tue, 24 Jan 2017 10:47:24 -0500 Received: from e24smtp05.br.ibm.com (e24smtp05.br.ibm.com [32.104.18.26]) by mx0a-001b2d01.pphosted.com with ESMTP id 285ee5ubh8-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 24 Jan 2017 10:47:23 -0500 Received: from localhost by e24smtp05.br.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 24 Jan 2017 13:47:21 -0200 Received: from d24relay01.br.ibm.com (d24relay01.br.ibm.com [9.8.31.16]) by d24dlp01.br.ibm.com (Postfix) with ESMTP id E14113520070 for ; Tue, 24 Jan 2017 10:46:46 -0500 (EST) Received: from d24av01.br.ibm.com (d24av01.br.ibm.com [9.8.31.91]) by d24relay01.br.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v0OFlJNw4722780 for ; Tue, 24 Jan 2017 13:47:19 -0200 Received: from d24av01.br.ibm.com (localhost [127.0.0.1]) by d24av01.br.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v0OFlI1l030334 for ; Tue, 24 Jan 2017 13:47:19 -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, sreekanth.reddy@broadcom.com, brking@linux.vnet.ibm.com, mauricfo@linux.vnet.ibm.com, linuxram@us.ibm.com, gpiccoli@linux.vnet.ibm.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 --- v1->v2: * Improved printk, by showing some variables too [suggested by Sreekanth]. 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..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))) { + 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; + } + 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