isci: Any reset indicated on an I/O completion escalates it to the error path.

If there is a pending device reset, the I/O is used to accomplish the reset by setting the
RESET bit in the task status, and then putting the task into the error handler
path using sas abort task.

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

3 files changed, 46 insertions, 27 deletions

diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c
index 153f419f1618..dc231c22ea93 100644
--- a/drivers/scsi/isci/host.c
+++ b/drivers/scsi/isci/host.c
@@ -290,17 +290,6 @@ static void isci_host_completion_routine(unsigned long data)
         list_splice_init(&isci_host->requests_to_complete,
                          &completed_request_list);
 
-        /* While holding the scic_lock take all of the normally completed
-         * I/Os off of the device's pending lists.
-         */
-        list_for_each_entry(request, &completed_request_list, completed_node) {
-
-                /* Remove the request from the remote device's list
-                * of pending requests.
-                */
-                list_del_init(&request->dev_node);
-        }
-
         /* Take the list of errored I/Os from the host. */
         list_splice_init(&isci_host->requests_to_errorback,
                          &errored_request_list);
diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
index c88e270b2b40..6cd80bbdae15 100644
--- a/drivers/scsi/isci/request.c
+++ b/drivers/scsi/isci/request.c
@@ -790,9 +790,9 @@ static void isci_task_save_for_upper_layer_completion(
 {
         struct sas_task *task = isci_request_access_task(request);
 
-        isci_task_set_completion_status(task, response, status,
-                                         task_notification_selection);
-
+        task_notification_selection
+                = isci_task_set_completion_status(task, response, status,
+                                                  task_notification_selection);
 
         /* Tasks aborted specifically by a call to the lldd_abort_task
          * function should not be completed to the host in the regular path.
@@ -811,6 +811,9 @@ static void isci_task_save_for_upper_layer_completion(
                 /* Add to the completed list. */
                 list_add(&request->completed_node,
                          &host->requests_to_complete);
+
+                /* Take the request off the device's pending request list. */
+                list_del_init(&request->dev_node);
                 break;
 
         case isci_perform_aborted_io_completion:
diff --git a/drivers/scsi/isci/task.h b/drivers/scsi/isci/task.h
index ced6a8be1b31..68d8e5e65a73 100644
--- a/drivers/scsi/isci/task.h
+++ b/drivers/scsi/isci/task.h
@@ -280,9 +280,10 @@ static inline void isci_task_all_done(
  * @response: This parameter is the response code for the completed task.
  * @status: This parameter is the status code for the completed task.
  *
- * none.
- */
-static inline void isci_task_set_completion_status(
+* @return The new notification mode for the request.
+*/
+static inline enum isci_completion_selection
+isci_task_set_completion_status(
         struct sas_task *task,
         enum service_response response,
         enum exec_status status,
@@ -295,15 +296,41 @@ static inline void isci_task_set_completion_status(
         task->task_status.resp = response;
         task->task_status.stat = status;
 
-        /* Don't set DONE (or clear AT_INITIATOR) for any task going into the
-         * error path, because the EH interprets that as a handled error condition.
-         * Also don't take action if there is a reset pending.
-         */
-        if ((task_notification_selection != isci_perform_error_io_completion)
-            && !(task->task_state_flags & SAS_TASK_NEED_DEV_RESET))
-                isci_set_task_doneflags(task);
+        /* If a device reset is being indicated, make sure the I/O
+        * is in the error path.
+        */
+        if (task->task_state_flags & SAS_TASK_NEED_DEV_RESET)
+                task_notification_selection = isci_perform_error_io_completion;
+
+        switch (task_notification_selection) {
+
+                case isci_perform_aborted_io_completion:
+                        /* This path can occur with task-managed requests as well as
+                        * requests terminated because of LUN or device resets.
+                        */
+                        /* Fall through to the normal case... */
+
+                case isci_perform_normal_io_completion:
+                        /* Normal notification (task_done) */
+                        isci_set_task_doneflags(task);
+                        break;
+
+                default:
+                        WARN_ON(FALSE);
+                        /* Fall through to the error case... */
+
+                case isci_perform_error_io_completion:
+                        /* Use sas_task_abort */
+                        /* Leave SAS_TASK_STATE_DONE clear
+                        *  Leave SAS_TASK_AT_INITIATOR set.
+                        */
+                        break;
+        }
 
         spin_unlock_irqrestore(&task->task_state_lock, flags);
+
+        return task_notification_selection;
+
 }
 /**
  * isci_task_complete_for_upper_layer() - This function completes the request
@@ -322,9 +349,9 @@ static inline void isci_task_complete_for_upper_layer(
         enum exec_status status,
         enum isci_completion_selection task_notification_selection)
 {
-        isci_task_set_completion_status(task, response, status,
-                                         task_notification_selection);
-
+        task_notification_selection
+                = isci_task_set_completion_status(task, response, status,
+                                                  task_notification_selection);
 
         /* Tasks aborted specifically by a call to the lldd_abort_task
          * function should not be completed to the host in the regular path.