isci: rework timer api

Prepare the timer api for the arrival of dynamic creation and
destruction events from the core.  It pretended to do this previously
but the core to date only used it in a static init-time only fashion.
This is an interim fix until a cleaner event queue can be developed.

1/ make all locking external to the api (add WARN_ONCE to verify)
2/ add a timer_destroy interface (to be used by the core)
3/ use del_timer_sync() prior to deallocating timer data
4/ delete the "timer_list" indirection, we only have timers allocated
   for the isci_host
5/ fix detection of timer list allocation errors

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/scsi/isci/events.c

@@ -75,35 +75,23 @@
  *    whenever the timer expires.
  * @controller: This parameter specifies the controller with which this timer
  *    is to be associated.
- * @cookie: This parameter specifies a piece of information that the user must
- *    retain.  This cookie is to be supplied by the user anytime a timeout
- *    occurs for the created timer.
+ * @cb_param: opaque callback parameter
  *
  * This method returns a handle to a timer object created by the user.  The
  * handle will be utilized for all further interactions relating to this timer.
  */
-void *isci_event_timer_create(
-	struct scic_sds_controller *controller,
-	void (*timer_callback)(void *),
-	void *cookie)
+void *isci_event_timer_create(struct scic_sds_controller *scic,
+			      void (*timer_callback)(void *),
+			      void *cb_param)
 {
-	struct isci_host *isci_host;
-	struct isci_timer *timer = NULL;
-
-	isci_host = (struct isci_host *)sci_object_get_association(controller);
+	struct isci_host *ihost = sci_object_get_association(scic);
+	struct isci_timer *itimer;
 
-	dev_dbg(&isci_host->pdev->dev,
-		"%s: isci_host = %p",
-		__func__, isci_host);
-
-	timer = isci_timer_create(&isci_host->timer_list_struct,
-				  isci_host,
-				  cookie,
-				  timer_callback);
+	itimer = isci_timer_create(ihost, cb_param, timer_callback);
 
-	dev_dbg(&isci_host->pdev->dev, "%s: timer = %p\n", __func__, timer);
+	dev_dbg(&ihost->pdev->dev, "%s: timer = %p\n", __func__, itimer);
 
-	return (void *)timer;
+	return itimer;
 }
 
 
@@ -146,14 +134,9 @@ void isci_event_timer_start(
  * @timer: This parameter specifies the timer to be stopped.
  *
  */
-void isci_event_timer_stop(
-	struct scic_sds_controller *controller,
-	void *timer)
+void isci_event_timer_stop(struct scic_sds_controller *controller, void *timer)
 {
-	struct isci_host *isci_host;
-
-	isci_host =
-		(struct isci_host *)sci_object_get_association(controller);
+	struct isci_host *isci_host = sci_object_get_association(controller);
 
 	dev_dbg(&isci_host->pdev->dev,
 		"%s: isci_host = %p, timer = %p\n",
@@ -162,6 +145,16 @@ void isci_event_timer_stop(
 	isci_timer_stop((struct isci_timer *)timer);
 }
 
+void isci_event_timer_destroy(struct scic_sds_controller *scic, void *timer)
+{
+        struct isci_host *ihost = sci_object_get_association(scic);
+
+	dev_dbg(&ihost->pdev->dev, "%s: ihost = %p, timer = %p\n",
+			__func__, ihost, timer);
+
+	isci_del_timer(ihost, timer);
+}
+
 /**
  * isci_event_controller_start_complete() - This user callback will inform the
  *    user that the controller has finished the start process. The associated

drivers/scsi/isci/events.h

@@ -111,6 +111,9 @@ void isci_event_timer_stop(
 	struct scic_sds_controller *controller,
 	void *timer);
 
+
+void isci_event_timer_destroy(struct scic_sds_controller *scic, void *timer);
+
 /**
  * isci_event_controller_start_complete() - This user callback will inform the
  *    user that the controller has finished the start process.

drivers/scsi/isci/host.c

@@ -349,9 +349,14 @@ void isci_host_deinit(struct isci_host *ihost)
 	}
 
 	set_bit(IHOST_STOP_PENDING, &ihost->flags);
+
+	spin_lock_irq(&ihost->scic_lock);
 	scic_controller_stop(scic, SCIC_CONTROLLER_STOP_TIMEOUT);
+	spin_unlock_irq(&ihost->scic_lock);
+
 	wait_for_stop(ihost);
 	scic_controller_reset(scic);
+	isci_timer_list_destroy(ihost);
 }
 
 static void __iomem *scu_base(struct isci_host *isci_host)
@@ -370,8 +375,6 @@ static void __iomem *smu_base(struct isci_host *isci_host)
 	return pcim_iomap_table(pdev)[SCI_SMU_BAR * 2] + SCI_SMU_BAR_SIZE * id;
 }
 
-#define SCI_MAX_TIMER_COUNT 25
-
 int isci_host_init(struct isci_host *isci_host)
 {
 	int err = 0;
@@ -382,11 +385,7 @@ int isci_host_init(struct isci_host *isci_host)
 	union scic_oem_parameters scic_oem_params;
 	union scic_user_parameters scic_user_params;
 
-	INIT_LIST_HEAD(&isci_host->timer_list_struct.timers);
-	isci_timer_list_construct(
-		&isci_host->timer_list_struct,
-		SCI_MAX_TIMER_COUNT
-		);
+	isci_timer_list_construct(isci_host);
 
 	controller = scic_controller_alloc(&isci_host->pdev->dev);
 
@@ -473,7 +472,17 @@ int isci_host_init(struct isci_host *isci_host)
 		}
 	}
 
+	tasklet_init(&isci_host->completion_tasklet,
+		     isci_host_completion_routine, (unsigned long)isci_host);
+
+	INIT_LIST_HEAD(&(isci_host->mdl_struct_list));
+
+	INIT_LIST_HEAD(&isci_host->requests_to_complete);
+	INIT_LIST_HEAD(&isci_host->requests_to_abort);
+
+	spin_lock_irq(&isci_host->scic_lock);
 	status = scic_controller_initialize(isci_host->core_controller);
+	spin_unlock_irq(&isci_host->scic_lock);
 	if (status != SCI_SUCCESS) {
 		dev_warn(&isci_host->pdev->dev,
 			 "%s: scic_controller_initialize failed -"
@@ -482,17 +491,8 @@ int isci_host_init(struct isci_host *isci_host)
 		return -ENODEV;
 	}
 
-	tasklet_init(&isci_host->completion_tasklet,
-		     isci_host_completion_routine, (unsigned long)isci_host);
-
-	INIT_LIST_HEAD(&(isci_host->mdl_struct_list));
-
-	INIT_LIST_HEAD(&isci_host->requests_to_complete);
-	INIT_LIST_HEAD(&isci_host->requests_to_abort);
-
 	/* populate mdl with dma memory. scu_mdl_allocate_coherent() */
 	err = isci_host_mdl_allocate_coherent(isci_host);
-
 	if (err)
 		return err;
 

drivers/scsi/isci/host.h

@@ -87,7 +87,7 @@ struct isci_host {
 	union scic_oem_parameters oem_parameters;
 
 	int id; /* unique within a given pci device */
-	struct isci_timer_list timer_list_struct;
+	struct list_head timers;
 	void *core_ctrl_memory;
 	struct dma_pool *dma_pool;
 	unsigned int dma_pool_alloc_size;

drivers/scsi/isci/task.c

@@ -475,14 +475,8 @@ int isci_task_execute_tmf(
 	}
 
 	/* Allocate the TMF timeout timer. */
-	tmf->timeout_timer = isci_timer_create(
-		&isci_host->timer_list_struct,
-		isci_host,
-		request,
-		isci_tmf_timeout_cb
-		);
-
 	spin_lock_irqsave(&isci_host->scic_lock, flags);
+	tmf->timeout_timer = isci_timer_create(isci_host, request, isci_tmf_timeout_cb);
 
 	/* Start the timer. */
 	if (tmf->timeout_timer)
@@ -557,9 +551,7 @@ int isci_task_execute_tmf(
 
 	/* Clean up the timer if needed. */
 	if (tmf->timeout_timer) {
-		isci_timer_stop(tmf->timeout_timer);
-		isci_timer_free(&isci_host->timer_list_struct,
-				tmf->timeout_timer);
+		isci_del_timer(isci_host, tmf->timeout_timer);
 		tmf->timeout_timer = NULL;
 	}
 
@@ -1468,10 +1460,7 @@ void isci_task_request_complete(
 
 	/* Manage the timer if it is still running. */
 	if (tmf->timeout_timer) {
-
-		isci_timer_stop(tmf->timeout_timer);
-		isci_timer_free(&isci_host->timer_list_struct,
-				tmf->timeout_timer);
+		isci_del_timer(isci_host, tmf->timeout_timer);
 		tmf->timeout_timer = NULL;
 	}