isci: Terminate outstanding TCs on TX/RX RNC suspensions.

TCs must only be terminated when RNCs are suspended.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

7 files changed, 188 insertions, 32 deletions

diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c
index 5832b13e7b07..d241b5722eb3 100644
--- a/drivers/scsi/isci/host.c
+++ b/drivers/scsi/isci/host.c
@@ -2696,18 +2696,18 @@ enum sci_status sci_controller_terminate_request(struct isci_host *ihost,
 			 __func__, ihost->sm.current_state_id);
 		return SCI_FAILURE_INVALID_STATE;
 	}
-
 	status = sci_io_request_terminate(ireq);
-	if (status != SCI_SUCCESS)
-		return status;
-
-	/*
-	 * Utilize the original post context command and or in the POST_TC_ABORT
-	 * request sub-type.
-	 */
-	sci_controller_post_request(ihost,
-				    ireq->post_context | SCU_CONTEXT_COMMAND_REQUEST_POST_TC_ABORT);
-	return SCI_SUCCESS;
+	if ((status == SCI_SUCCESS) &&
+	    !test_bit(IREQ_PENDING_ABORT, &ireq->flags) &&
+	    !test_and_set_bit(IREQ_TC_ABORT_POSTED, &ireq->flags)) {
+		/* Utilize the original post context command and or in the
+		 * POST_TC_ABORT request sub-type.
+		 */
+		sci_controller_post_request(
+			ihost, ireq->post_context |
+				SCU_CONTEXT_COMMAND_REQUEST_POST_TC_ABORT);
+	}
+	return status;
 }
 
 /**
diff --git a/drivers/scsi/isci/remote_device.c b/drivers/scsi/isci/remote_device.c
index b1a8000a5ef8..9f03877534d2 100644
--- a/drivers/scsi/isci/remote_device.c
+++ b/drivers/scsi/isci/remote_device.c
@@ -133,6 +133,50 @@ static void isci_remote_device_ready(struct isci_host *ihost, struct isci_remote
 		wake_up(&ihost->eventq);
 }
 
+static enum sci_status sci_remote_device_suspend(
+	struct isci_remote_device *idev)
+{
+	return sci_remote_node_context_suspend(
+		&idev->rnc,
+		SCI_SOFTWARE_SUSPENSION,
+		SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT,
+		NULL, NULL);
+}
+
+enum sci_status isci_remote_device_suspend(
+	struct isci_host *ihost,
+	struct isci_remote_device *idev)
+{
+	enum sci_status status;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ihost->scic_lock, flags);
+
+	if (isci_lookup_device(idev->domain_dev) == NULL) {
+		spin_unlock_irqrestore(&ihost->scic_lock, flags);
+		status = SCI_FAILURE;
+	} else {
+		status = sci_remote_device_suspend(idev);
+		spin_unlock_irqrestore(&ihost->scic_lock, flags);
+		if (status == SCI_SUCCESS) {
+			wait_event(ihost->eventq,
+				   test_bit(IDEV_TXRX_SUSPENDED, &idev->flags)
+				|| !test_bit(IDEV_ALLOCATED, &idev->flags));
+
+			status = test_bit(IDEV_TXRX_SUSPENDED, &idev->flags)
+					? SCI_SUCCESS : SCI_FAILURE;
+			dev_dbg(&ihost->pdev->dev,
+				"%s: idev=%p, wait done, device is %s\n",
+				__func__, idev,
+				test_bit(IDEV_TXRX_SUSPENDED, &idev->flags)
+					? "<suspended>" : "<deallocated!>");
+
+		}
+		isci_put_device(idev);
+	}
+	return status;
+}
+
 /* called once the remote node context is ready to be freed.
  * The remote device can now report that its stop operation is complete. none
  */
@@ -144,7 +188,9 @@ static void rnc_destruct_done(void *_dev)
 	sci_change_state(&idev->sm, SCI_DEV_STOPPED);
 }
 
-static enum sci_status sci_remote_device_terminate_requests(struct isci_remote_device *idev)
+static enum sci_status sci_remote_device_terminate_requests_checkabort(
+	struct isci_remote_device *idev,
+	int check_abort_pending)
 {
 	struct isci_host *ihost = idev->owning_port->owning_controller;
 	enum sci_status status  = SCI_SUCCESS;
@@ -155,7 +201,9 @@ static enum sci_status sci_remote_device_terminate_requests(struct isci_remote_d
 		enum sci_status s;
 
 		if (!test_bit(IREQ_ACTIVE, &ireq->flags) ||
-		    ireq->target_device != idev)
+		    (ireq->target_device != idev) ||
+		    (check_abort_pending && !test_bit(IREQ_PENDING_ABORT,
+						      &ireq->flags)))
 			continue;
 
 		s = sci_controller_terminate_request(ihost, idev, ireq);
@@ -166,6 +214,12 @@ static enum sci_status sci_remote_device_terminate_requests(struct isci_remote_d
 	return status;
 }
 
+enum sci_status sci_remote_device_terminate_requests(
+	struct isci_remote_device *idev)
+{
+	return sci_remote_device_terminate_requests_checkabort(idev, 0);
+}
+
 enum sci_status sci_remote_device_stop(struct isci_remote_device *idev,
 					u32 timeout)
 {
@@ -265,14 +319,6 @@ enum sci_status sci_remote_device_reset_complete(struct isci_remote_device *idev
 	return SCI_SUCCESS;
 }
 
-enum sci_status sci_remote_device_suspend(struct isci_remote_device *idev)
-{
-	return sci_remote_node_context_suspend(&idev->rnc,
-					       SCI_SOFTWARE_SUSPENSION,
-					       SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT,
-					       NULL, NULL);
-}
-
 enum sci_status sci_remote_device_frame_handler(struct isci_remote_device *idev,
 						     u32 frame_index)
 {
@@ -1186,7 +1232,7 @@ static enum sci_status sci_remote_device_ea_construct(struct isci_port *iport,
  * the device when there have been no phys added to it.
  */
 static enum sci_status sci_remote_device_start(struct isci_remote_device *idev,
-						u32 timeout)
+					       u32 timeout)
 {
 	struct sci_base_state_machine *sm = &idev->sm;
 	enum sci_remote_device_states state = sm->current_state_id;
@@ -1413,3 +1459,41 @@ int isci_remote_device_found(struct domain_device *dev)
 
 	return status == SCI_SUCCESS ? 0 : -ENODEV;
 }
+
+enum sci_status isci_remote_device_reset(
+	struct isci_remote_device *idev)
+{
+	struct isci_host *ihost = dev_to_ihost(idev->domain_dev);
+	unsigned long flags;
+	enum sci_status status;
+
+	/* Wait for the device suspend. */
+	status = isci_remote_device_suspend(ihost, idev);
+	if (status != SCI_SUCCESS) {
+		dev_dbg(&ihost->pdev->dev,
+			"%s: isci_remote_device_suspend(%p) returned %d!\n",
+			__func__, idev, status);
+		return status;
+	}
+	spin_lock_irqsave(&ihost->scic_lock, flags);
+	status = sci_remote_device_reset(idev);
+	spin_unlock_irqrestore(&ihost->scic_lock, flags);
+	if (status != SCI_SUCCESS) {
+		dev_dbg(&ihost->pdev->dev,
+			"%s: sci_remote_device_reset(%p) returned %d!\n",
+			__func__, idev, status);
+	}
+	return status;
+}
+
+int isci_remote_device_is_safe_to_abort(
+	struct isci_remote_device *idev)
+{
+	return sci_remote_node_context_is_safe_to_abort(&idev->rnc);
+}
+
+enum sci_status sci_remote_device_abort_requests_pending_abort(
+	struct isci_remote_device *idev)
+{
+	return sci_remote_device_terminate_requests_checkabort(idev, 1);
+}
diff --git a/drivers/scsi/isci/remote_device.h b/drivers/scsi/isci/remote_device.h
index 39159053b7ff..ae508ee33664 100644
--- a/drivers/scsi/isci/remote_device.h
+++ b/drivers/scsi/isci/remote_device.h
@@ -85,6 +85,7 @@ struct isci_remote_device {
 	#define IDEV_GONE 3
 	#define IDEV_IO_READY 4
 	#define IDEV_IO_NCQERROR 5
+	#define IDEV_TXRX_SUSPENDED 6
 	unsigned long flags;
 	struct kref kref;
 	struct isci_port *isci_port;
@@ -335,4 +336,13 @@ void sci_remote_device_post_request(
 	struct isci_remote_device *idev,
 	u32 request);
 
+enum sci_status sci_remote_device_terminate_requests(
+	struct isci_remote_device *idev);
+
+int isci_remote_device_is_safe_to_abort(
+	struct isci_remote_device *idev);
+
+enum sci_status
+sci_remote_device_abort_requests_pending_abort(
+	struct isci_remote_device *idev);
 #endif /* !defined(_ISCI_REMOTE_DEVICE_H_) */
diff --git a/drivers/scsi/isci/remote_node_context.c b/drivers/scsi/isci/remote_node_context.c
index f180c726c5bb..7a8347e51767 100644
--- a/drivers/scsi/isci/remote_node_context.c
+++ b/drivers/scsi/isci/remote_node_context.c
@@ -268,6 +268,8 @@ static void sci_remote_node_context_invalidating_state_enter(struct sci_base_sta
 {
 	struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
 
+	/* Terminate outstanding requests pending abort. */
+	sci_remote_device_abort_requests_pending_abort(rnc_to_dev(rnc));
 	sci_remote_node_context_invalidate_context_buffer(rnc);
 }
 
@@ -312,10 +314,28 @@ static void sci_remote_node_context_tx_suspended_state_enter(struct sci_base_sta
 static void sci_remote_node_context_tx_rx_suspended_state_enter(struct sci_base_state_machine *sm)
 {
 	struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
+	struct isci_remote_device *idev = rnc_to_dev(rnc);
+	struct isci_host *ihost = idev->owning_port->owning_controller;
+
+	set_bit(IDEV_TXRX_SUSPENDED, &idev->flags);
 
+	/* Terminate outstanding requests pending abort. */
+	sci_remote_device_abort_requests_pending_abort(idev);
+
+	wake_up(&ihost->eventq);
 	sci_remote_node_context_continue_state_transitions(rnc);
 }
 
+static void sci_remote_node_context_tx_rx_suspended_state_exit(
+	struct sci_base_state_machine *sm)
+{
+	struct sci_remote_node_context *rnc
+		= container_of(sm, typeof(*rnc), sm);
+	struct isci_remote_device *idev = rnc_to_dev(rnc);
+
+	clear_bit(IDEV_TXRX_SUSPENDED, &idev->flags);
+}
+
 static void sci_remote_node_context_await_suspend_state_exit(
 	struct sci_base_state_machine *sm)
 {
@@ -346,6 +366,8 @@ static const struct sci_base_state sci_remote_node_context_state_table[] = {
 	},
 	[SCI_RNC_TX_RX_SUSPENDED] = {
 		.enter_state = sci_remote_node_context_tx_rx_suspended_state_enter,
+		.exit_state
+			= sci_remote_node_context_tx_rx_suspended_state_exit,
 	},
 	[SCI_RNC_AWAIT_SUSPENSION] = {
 		.exit_state = sci_remote_node_context_await_suspend_state_exit,
@@ -515,6 +537,13 @@ enum sci_status sci_remote_node_context_suspend(
 	struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
 	enum sci_status status = SCI_FAILURE_INVALID_STATE;
 
+	dev_dbg(scirdev_to_dev(idev),
+		"%s: current state %d, current suspend_type %x dest state %d,"
+			" arg suspend_reason %d, arg suspend_type %x",
+		__func__, state, sci_rnc->suspend_type,
+		sci_rnc->destination_state, suspend_reason,
+		suspend_type);
+
 	/* Disable automatic state continuations if explicitly suspending. */
 	if (suspend_reason == SCI_SOFTWARE_SUSPENSION)
 		sci_rnc->destination_state
@@ -546,7 +575,10 @@ enum sci_status sci_remote_node_context_suspend(
 	sci_rnc->suspend_type  = suspend_type;
 
 	if (status == SCI_SUCCESS) { /* Already in the destination state? */
+		struct isci_host *ihost = idev->owning_port->owning_controller;
+
 		sci_remote_node_context_notify_user(sci_rnc);
+		wake_up_all(&ihost->eventq); /* Let observers look. */
 		return SCI_SUCCESS;
 	}
 	if (suspend_reason == SCI_SOFTWARE_SUSPENSION) {
@@ -661,3 +693,27 @@ enum sci_status sci_remote_node_context_start_task(struct sci_remote_node_contex
 		return SCI_FAILURE_INVALID_STATE;
 	}
 }
+
+int sci_remote_node_context_is_safe_to_abort(
+	struct sci_remote_node_context *sci_rnc)
+{
+	enum scis_sds_remote_node_context_states state;
+
+	state = sci_rnc->sm.current_state_id;
+	switch (state) {
+	case SCI_RNC_INVALIDATING:
+	case SCI_RNC_TX_RX_SUSPENDED:
+		return 1;
+	case SCI_RNC_POSTING:
+	case SCI_RNC_RESUMING:
+	case SCI_RNC_READY:
+	case SCI_RNC_TX_SUSPENDED:
+	case SCI_RNC_AWAIT_SUSPENSION:
+	case SCI_RNC_INITIAL:
+		return 0;
+	default:
+		dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
+			 "%s: invalid state %d\n", __func__, state);
+		return 0;
+	}
+}
diff --git a/drivers/scsi/isci/remote_node_context.h b/drivers/scsi/isci/remote_node_context.h
index 276fc491e8f9..5ddf88b53133 100644
--- a/drivers/scsi/isci/remote_node_context.h
+++ b/drivers/scsi/isci/remote_node_context.h
@@ -214,5 +214,7 @@ enum sci_status sci_remote_node_context_start_task(struct sci_remote_node_contex
 							struct isci_request *ireq);
 enum sci_status sci_remote_node_context_start_io(struct sci_remote_node_context *sci_rnc,
 						      struct isci_request *ireq);
+int sci_remote_node_context_is_safe_to_abort(
+	struct sci_remote_node_context *sci_rnc);
 
 #endif  /* _SCIC_SDS_REMOTE_NODE_CONTEXT_H_ */
diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
index 605dc68cbf79..1f314d0d71d5 100644
--- a/drivers/scsi/isci/request.c
+++ b/drivers/scsi/isci/request.c
@@ -863,6 +863,8 @@ sci_io_request_terminate(struct isci_request *ireq)
 
 	switch (state) {
 	case SCI_REQ_CONSTRUCTED:
+		/* Set to make sure no HW terminate posting is done: */
+		set_bit(IREQ_TC_ABORT_POSTED, &ireq->flags);
 		ireq->scu_status = SCU_TASK_DONE_TASK_ABORT;
 		ireq->sci_status = SCI_FAILURE_IO_TERMINATED;
 		sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
@@ -883,8 +885,7 @@ sci_io_request_terminate(struct isci_request *ireq)
 	case SCI_REQ_ATAPI_WAIT_PIO_SETUP:
 	case SCI_REQ_ATAPI_WAIT_D2H:
 	case SCI_REQ_ATAPI_WAIT_TC_COMP:
-		sci_change_state(&ireq->sm, SCI_REQ_ABORTING);
-		return SCI_SUCCESS;
+		/* Fall through and change state to ABORTING... */
 	case SCI_REQ_TASK_WAIT_TC_RESP:
 		/* The task frame was already confirmed to have been
 		 * sent by the SCU HW.  Since the state machine is
@@ -893,20 +894,21 @@ sci_io_request_terminate(struct isci_request *ireq)
 		 * and don't wait for the task response.
 		 */
 		sci_change_state(&ireq->sm, SCI_REQ_ABORTING);
-		sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
-		return SCI_SUCCESS;
+		/* Fall through and handle like ABORTING... */
 	case SCI_REQ_ABORTING:
-		/* If a request has a termination requested twice, return
-		 * a failure indication, since HW confirmation of the first
-		 * abort is still outstanding.
+		if (!isci_remote_device_is_safe_to_abort(ireq->target_device))
+			set_bit(IREQ_PENDING_ABORT, &ireq->flags);
+		else
+			clear_bit(IREQ_PENDING_ABORT, &ireq->flags);
+		/* If the request is only waiting on the remote device
+		 * suspension, return SUCCESS so the caller will wait too.
 		 */
+		return SCI_SUCCESS;
 	case SCI_REQ_COMPLETED:
 	default:
 		dev_warn(&ireq->owning_controller->pdev->dev,
 			 "%s: SCIC IO Request requested to abort while in wrong "
-			 "state %d\n",
-			 __func__,
-			 ireq->sm.current_state_id);
+			 "state %d\n", __func__, ireq->sm.current_state_id);
 		break;
 	}
 
diff --git a/drivers/scsi/isci/request.h b/drivers/scsi/isci/request.h
index e845a31ecebb..8d55f78010aa 100644
--- a/drivers/scsi/isci/request.h
+++ b/drivers/scsi/isci/request.h
@@ -102,6 +102,8 @@ struct isci_request {
 	#define IREQ_TERMINATED 1
 	#define IREQ_TMF 2
 	#define IREQ_ACTIVE 3
+	#define IREQ_PENDING_ABORT 4 /* Set == device was not suspended yet */
+	#define IREQ_TC_ABORT_POSTED 5
 	unsigned long flags;
 	/* XXX kill ttype and ttype_ptr, allocate full sas_task */
 	union ttype_ptr_union {