[SCSI] libsas: remove ata_port.lock management duties from lldds

Each libsas driver (mvsas, pm8001, and isci) has invented a different
method for managing the ap->lock.  The lock is held by the ata
->queuecommand() path.  mvsas drops it prior to acquiring any internal
locks which allows it to hold its internal lock across calls to
task->task_done().  This capability is important as it is the only way
the driver can flush task->task_done() instances to guarantee that it no
longer has any in-flight references to a domain_device at
->lldd_dev_gone() time.

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

3 files changed, 3 insertions, 42 deletions

diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
index 751368b46b44..788daeedc89f 100644
--- a/drivers/scsi/isci/request.c
+++ b/drivers/scsi/isci/request.c
@@ -3796,8 +3796,7 @@ int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *ide
 		/* Cause this task to be scheduled in the SCSI error
 		 * handler thread.
 		 */
-		isci_execpath_callback(ihost, task,
-				       sas_task_abort);
+		sas_task_abort(task);
 
 		/* Change the status, since we are holding
 		 * the I/O until it is managed by the SCSI
diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index f5a3f7d2bdab..4bd88ef83cdf 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -96,8 +96,7 @@ static void isci_task_refuse(struct isci_host *ihost, struct sas_task *task,
 			__func__, task, response, status);
 
 		task->lldd_task = NULL;
-
-		isci_execpath_callback(ihost, task, task->task_done);
+		task->task_done(task);
 		break;
 
 	case isci_perform_aborted_io_completion:
@@ -117,8 +116,7 @@ static void isci_task_refuse(struct isci_host *ihost, struct sas_task *task,
 			"%s: Error - task = %p, response=%d, "
 			"status=%d\n",
 			__func__, task, response, status);
-
-		isci_execpath_callback(ihost, task, sas_task_abort);
+		sas_task_abort(task);
 		break;
 
 	default:
diff --git a/drivers/scsi/isci/task.h b/drivers/scsi/isci/task.h
index 1b27b3797c6c..bb472c339523 100644
--- a/drivers/scsi/isci/task.h
+++ b/drivers/scsi/isci/task.h
@@ -321,40 +321,4 @@ isci_task_set_completion_status(
 	return task_notification_selection;
 
 }
-/**
-* isci_execpath_callback() - This function is called from the task
-* execute path when the task needs to callback libsas about the submit-time
-* task failure.  The callback occurs either through the task's done function
-* or through sas_task_abort.  In the case of regular non-discovery SATA/STP I/O
-* requests, libsas takes the host lock before calling execute task.  Therefore
-* in this situation the host lock must be managed before calling the func.
-*
-* @ihost: This parameter is the controller to which the I/O request was sent.
-* @task: This parameter is the I/O request.
-* @func: This parameter is the function to call in the correct context.
-* @status: This parameter is the status code for the completed task.
-*
-*/
-static inline void isci_execpath_callback(struct isci_host *ihost,
-					  struct sas_task  *task,
-					  void (*func)(struct sas_task *))
-{
-	struct domain_device *dev = task->dev;
-
-	if (dev_is_sata(dev) && task->uldd_task) {
-		unsigned long flags;
-
-		/* Since we are still in the submit path, and since
-		 * libsas takes the host lock on behalf of SATA
-		 * devices before I/O starts (in the non-discovery case),
-		 * we need to unlock before we can call the callback function.
-		 */
-		raw_local_irq_save(flags);
-		spin_unlock(dev->sata_dev.ap->lock);
-		func(task);
-		spin_lock(dev->sata_dev.ap->lock);
-		raw_local_irq_restore(flags);
-	} else
-		func(task);
-}
 #endif /* !defined(_SCI_TASK_H_) */