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Violators will be prosecuted for from ; Wed, 21 Jun 2017 20:15:14 -0600 Received: from b03cxnp08026.gho.boulder.ibm.com (9.17.130.18) by e37.co.us.ibm.com (192.168.1.137) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Wed, 21 Jun 2017 20:15:11 -0600 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v5M2F90K63373394; Wed, 21 Jun 2017 19:15:09 -0700 Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3A3D378059; Wed, 21 Jun 2017 20:15:09 -0600 (MDT) Received: from p8tul1-build.aus.stglabs.ibm.com (unknown [9.3.141.206]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTP id C57BE78037; Wed, 21 Jun 2017 20:15:08 -0600 (MDT) From: Uma Krishnan To: linux-scsi@vger.kernel.org, James Bottomley , "Martin K. Petersen" , "Matthew R. Ochs" , "Manoj N. Kumar" Cc: linuxppc-dev@lists.ozlabs.org, Ian Munsie , Andrew Donnellan , Frederic Barrat , Christophe Lombard Subject: [PATCH 08/17] cxlflash: Add scsi command abort handler Date: Wed, 21 Jun 2017 21:15:06 -0500 X-Mailer: git-send-email 2.1.0 In-Reply-To: <1498097563-8680-1-git-send-email-ukrishn@linux.vnet.ibm.com> References: <1498097563-8680-1-git-send-email-ukrishn@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17062202-0024-0000-0000-000016B26111 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007269; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000214; SDB=6.00878072; UDB=6.00437482; IPR=6.00658213; BA=6.00005434; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015913; XFM=3.00000015; UTC=2017-06-22 02:15:12 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17062202-0025-0000-0000-00004B7CC0B2 Message-Id: <1498097706-8970-1-git-send-email-ukrishn@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-06-22_01:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1706220037 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP To date, CXL flash devices do not support a single command abort operation. Instead, the SISLite specification provides a context reset operation to cleanup all pending commands for a given context. When a context reset is successful, it is guaranteed that the AFU has aborted all currently pending I/O. This sequence is less invasive than a device or host reset and can be executed to support scsi command abort requests. Add eh_abort_handler callback support to process command timeouts and abort requests. Signed-off-by: Uma Krishnan Acked-by: Matthew R. Ochs --- drivers/scsi/cxlflash/main.c | 61 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 0a3de42..ceb247b 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -228,6 +228,10 @@ static void flush_pending_cmds(struct hwq *hwq) * @hwq: Hardware queue owning the context to be reset. * @reset_reg: MMIO register to perform reset. * + * When the reset is successful, the SISLite specification guarantees that + * the AFU has aborted all currently pending I/O. Accordingly, these commands + * must be flushed. + * * Return: 0 on success, -errno on failure */ static int context_reset(struct hwq *hwq, __be64 __iomem *reset_reg) @@ -237,9 +241,12 @@ static int context_reset(struct hwq *hwq, __be64 __iomem *reset_reg) int rc = -ETIMEDOUT; int nretry = 0; u64 val = 0x1; + ulong lock_flags; dev_dbg(dev, "%s: hwq=%p\n", __func__, hwq); + spin_lock_irqsave(&hwq->hsq_slock, lock_flags); + writeq_be(val, reset_reg); do { val = readq_be(reset_reg); @@ -252,6 +259,11 @@ static int context_reset(struct hwq *hwq, __be64 __iomem *reset_reg) udelay(1 << nretry); } while (nretry++ < MC_ROOM_RETRY_CNT); + if (!rc) + flush_pending_cmds(hwq); + + spin_unlock_irqrestore(&hwq->hsq_slock, lock_flags); + dev_dbg(dev, "%s: returning rc=%d, val=%016llx nretry=%d\n", __func__, rc, val, nretry); return rc; @@ -2256,6 +2268,54 @@ int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t ctx_hndl_u, } /** + * cxlflash_eh_abort_handler() - abort a SCSI command + * @scp: SCSI command to abort. + * + * CXL Flash devices do not support a single command abort. Reset the context + * as per SISLite specification. Flush any pending commands in the hardware + * queue before the reset. + * + * Return: SUCCESS/FAILED as defined in scsi/scsi.h + */ +static int cxlflash_eh_abort_handler(struct scsi_cmnd *scp) +{ + int rc = FAILED; + struct Scsi_Host *host = scp->device->host; + struct cxlflash_cfg *cfg = shost_priv(host); + struct afu_cmd *cmd = sc_to_afuc(scp); + struct device *dev = &cfg->dev->dev; + struct afu *afu = cfg->afu; + struct hwq *hwq = get_hwq(afu, cmd->hwq_index); + + dev_dbg(dev, "%s: (scp=%p) %d/%d/%d/%llu " + "cdb=(%08x-%08x-%08x-%08x)\n", __func__, scp, host->host_no, + scp->device->channel, scp->device->id, scp->device->lun, + get_unaligned_be32(&((u32 *)scp->cmnd)[0]), + get_unaligned_be32(&((u32 *)scp->cmnd)[1]), + get_unaligned_be32(&((u32 *)scp->cmnd)[2]), + get_unaligned_be32(&((u32 *)scp->cmnd)[3])); + + /* When the state is not normal, another reset/reload is in progress. + * Return failed and the mid-layer will invoke host reset handler. + */ + if (cfg->state != STATE_NORMAL) { + dev_dbg(dev, "%s: Invalid state for abort, state=%d\n", + __func__, cfg->state); + goto out; + } + + rc = afu->context_reset(hwq); + if (unlikely(rc)) + goto out; + + rc = SUCCESS; + +out: + dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** * cxlflash_eh_device_reset_handler() - reset a single LUN * @scp: SCSI command to send. * @@ -2969,6 +3029,7 @@ static struct scsi_host_template driver_template = { .ioctl = cxlflash_ioctl, .proc_name = CXLFLASH_NAME, .queuecommand = cxlflash_queuecommand, + .eh_abort_handler = cxlflash_eh_abort_handler, .eh_device_reset_handler = cxlflash_eh_device_reset_handler, .eh_host_reset_handler = cxlflash_eh_host_reset_handler, .change_queue_depth = cxlflash_change_queue_depth,