From: Xiaofei Tan <tanxiaofei@huawei.com>
Date: Sat, 9 Dec 2017 01:16:46 +0800
Subject: scsi: hisi_sas: judge result of internal abort
Git-commit: 813709f2e1e07fa872c05f43801a05828d33a70a
Patch-mainline: v4.16-rc1
References: FATE#326253

Normally, hardware should ensure that internal abort timeout will never
happen. If happen, it would be an SoC failure. What's more, HW will not
process any other commands if an internal abort hasn't return CQ, and they
will time out also.

So, we should judge the result of internal abort in SCSI EH, if it is failed,
we should give up to do TMF/softreset and return failure to the upper layer
directly.

This patch do following things to achieve this:

1. When internal abort timeout happened, we set return value to -EIO in
   hisi_sas_internal_task_abort().

2. If prep_abort() is not support, let hisi_sas_internal_task_abort() return
   TMF_RESP_FUNC_FAILED.

3. If hisi_sas_internal_task_abort() return an negative number, it can be
   thought that it not executed properly or internal abort timeout. Then we
   won't do behind TMF or softreset, and return failure directly.

Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
 drivers/scsi/hisi_sas/hisi_sas_main.c | 38 ++++++++++++++++++++++++++++-------
 1 file changed, 31 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 7446a39f9442..1b9c48c99968 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -1184,6 +1184,11 @@ static int hisi_sas_abort_task(struct sas_task *task)
 
 		rc2 = hisi_sas_internal_task_abort(hisi_hba, device,
 						   HISI_SAS_INT_ABT_CMD, tag);
+		if (rc2 < 0) {
+			dev_err(dev, "abort task: internal abort (%d)\n", rc2);
+			return TMF_RESP_FUNC_FAILED;
+		}
+
 		/*
 		 * If the TMF finds that the IO is not in the device and also
 		 * the internal abort does not succeed, then it is safe to
@@ -1201,8 +1206,12 @@ static int hisi_sas_abort_task(struct sas_task *task)
 	} else if (task->task_proto & SAS_PROTOCOL_SATA ||
 		task->task_proto & SAS_PROTOCOL_STP) {
 		if (task->dev->dev_type == SAS_SATA_DEV) {
-			hisi_sas_internal_task_abort(hisi_hba, device,
-						     HISI_SAS_INT_ABT_DEV, 0);
+			rc = hisi_sas_internal_task_abort(hisi_hba, device,
+						HISI_SAS_INT_ABT_DEV, 0);
+			if (rc < 0) {
+				dev_err(dev, "abort task: internal abort failed\n");
+				goto out;
+			}
 			hisi_sas_dereg_device(hisi_hba, device);
 			rc = hisi_sas_softreset_ata_disk(device);
 		}
@@ -1213,7 +1222,8 @@ static int hisi_sas_abort_task(struct sas_task *task)
 
 		rc = hisi_sas_internal_task_abort(hisi_hba, device,
 			     HISI_SAS_INT_ABT_CMD, tag);
-		if (rc == TMF_RESP_FUNC_FAILED && task->lldd_task) {
+		if (((rc < 0) || (rc == TMF_RESP_FUNC_FAILED)) &&
+					task->lldd_task) {
 			spin_lock_irqsave(&hisi_hba->lock, flags);
 			hisi_sas_do_release_task(hisi_hba, task, slot);
 			spin_unlock_irqrestore(&hisi_hba->lock, flags);
@@ -1263,15 +1273,20 @@ static int hisi_sas_I_T_nexus_reset(struct domain_device *device)
 {
 	struct hisi_sas_device *sas_dev = device->lldd_dev;
 	struct hisi_hba *hisi_hba = dev_to_hisi_hba(device);
-	unsigned long flags;
+	struct device *dev = hisi_hba->dev;
 	int rc = TMF_RESP_FUNC_FAILED;
+	unsigned long flags;
 
 	if (sas_dev->dev_status != HISI_SAS_DEV_EH)
 		return TMF_RESP_FUNC_FAILED;
 	sas_dev->dev_status = HISI_SAS_DEV_NORMAL;
 
-	hisi_sas_internal_task_abort(hisi_hba, device,
+	rc = hisi_sas_internal_task_abort(hisi_hba, device,
 					HISI_SAS_INT_ABT_DEV, 0);
+	if (rc < 0) {
+		dev_err(dev, "I_T nexus reset: internal abort (%d)\n", rc);
+		return TMF_RESP_FUNC_FAILED;
+	}
 	hisi_sas_dereg_device(hisi_hba, device);
 
 	rc = hisi_sas_debug_I_T_nexus_reset(device);
@@ -1299,8 +1314,10 @@ static int hisi_sas_lu_reset(struct domain_device *device, u8 *lun)
 		/* Clear internal IO and then hardreset */
 		rc = hisi_sas_internal_task_abort(hisi_hba, device,
 						  HISI_SAS_INT_ABT_DEV, 0);
-		if (rc == TMF_RESP_FUNC_FAILED)
+		if (rc < 0) {
+			dev_err(dev, "lu_reset: internal abort failed\n");
 			goto out;
+		}
 		hisi_sas_dereg_device(hisi_hba, device);
 
 		phy = sas_get_local_phy(device);
@@ -1497,8 +1514,14 @@ hisi_sas_internal_task_abort(struct hisi_hba *hisi_hba,
 	struct device *dev = hisi_hba->dev;
 	int res;
 
+	/*
+	 * The interface is not realized means this HW don't support internal
+	 * abort, or don't need to do internal abort. Then here, we return
+	 * TMF_RESP_FUNC_FAILED and let other steps go on, which depends that
+	 * the internal abort has been executed and returned CQ.
+	 */
 	if (!hisi_hba->hw->prep_abort)
-		return -EOPNOTSUPP;
+		return TMF_RESP_FUNC_FAILED;
 
 	task = sas_alloc_slow_task(GFP_KERNEL);
 	if (!task)
@@ -1530,6 +1553,7 @@ hisi_sas_internal_task_abort(struct hisi_hba *hisi_hba,
 			if (slot)
 				slot->task = NULL;
 			dev_err(dev, "internal task abort: timeout and not done.\n");
+			res = -EIO;
 			goto exit;
 		} else
 			dev_err(dev, "internal task abort: timeout.\n");