isci: fix fragile/conditional isci_host lookups

A domain_device can always reference back to ->lldd_ha unlike local lldd
structures.  Fix up cases where the driver uses local objects to look up the
isci_host.  This also changes the calling conventions of some routines to
expect a valid isci_host parameter rather than re-lookup the pointer on entry.

Incidentally cleans up some macros that are longer to type than the open-coded
equivalent:
  isci_host_from_sas_ha
  isci_dev_from_domain_dev

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

1 files changed, 27 insertions, 60 deletions

diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index 5bcea60fd8c4..c6c97ad58c9f 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -146,7 +146,7 @@ static void isci_task_refuse(struct isci_host *ihost, struct sas_task *task,
  */
 int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags)
 {
-        struct isci_host *ihost = task->dev->port->ha->lldd_ha;
+        struct isci_host *ihost = dev_to_ihost(task->dev);
         struct isci_request *request = NULL;
         struct isci_remote_device *device;
         unsigned long flags;
@@ -169,7 +169,7 @@ int isci_task_execute_task(struct sas_task *task, int num, gfp_t gfp_flags)
                         "task = %p, num = %d; dev = %p; cmd = %p\n",
                             task, num, task->dev, task->uldd_task);
 
-                device = isci_dev_from_domain_dev(task->dev);
+                device = task->dev->lldd_dev;
 
                 if (device)
                         device_status = device->status;
@@ -593,7 +593,6 @@ static void isci_task_build_abort_task_tmf(
 
 static struct isci_request *isci_task_get_request_from_task(
         struct sas_task *task,
-        struct isci_host **isci_host,
         struct isci_remote_device **isci_device)
 {
 
@@ -609,9 +608,6 @@ static struct isci_request *isci_task_get_request_from_task(
             (task->task_state_flags & SAS_TASK_AT_INITIATOR) &&
             (request != NULL)) {
 
-                if (isci_host != NULL)
-                        *isci_host = request->isci_host;
-
                 if (isci_device != NULL)
                         *isci_device = request->isci_device;
         }
@@ -1027,26 +1023,17 @@ static int isci_task_send_lu_reset_sas(
  *
  * status, zero indicates success.
  */
-int isci_task_lu_reset(
-        struct domain_device *domain_device,
-        u8 *lun)
+int isci_task_lu_reset(struct domain_device *domain_device, u8 *lun)
 {
-        struct isci_host *isci_host = NULL;
+        struct isci_host *isci_host = dev_to_ihost(domain_device);
         struct isci_remote_device *isci_device = NULL;
         int ret;
         bool device_stopping = false;
 
-        if (domain_device == NULL) {
-                pr_warn("%s: domain_device == NULL\n", __func__);
-                return TMF_RESP_FUNC_FAILED;
-        }
-
-        isci_device = isci_dev_from_domain_dev(domain_device);
-
-        if (domain_device->port != NULL)
-                isci_host = isci_host_from_sas_ha(domain_device->port->ha);
+        isci_device = domain_device->lldd_dev;
 
-        pr_debug("%s: domain_device=%p, isci_host=%p; isci_device=%p\n",
+        dev_dbg(&isci_host->pdev->dev,
+                "%s: domain_device=%p, isci_host=%p; isci_device=%p\n",
                  __func__, domain_device, isci_host, isci_device);
 
         if (isci_device != NULL)
@@ -1057,24 +1044,18 @@ int isci_task_lu_reset(
          * device's list, fail this LUN reset request in order to
          * escalate to the device reset.
          */
-        if ((isci_device == NULL) ||
-            (isci_host == NULL) ||
-            ((isci_host != NULL) &&
-             (isci_device != NULL) &&
-             (device_stopping ||
-              (isci_device_is_reset_pending(isci_host, isci_device))))) {
+        if (!isci_device || device_stopping ||
+            isci_device_is_reset_pending(isci_host, isci_device)) {
                 dev_warn(&isci_host->pdev->dev,
-                         "%s: No dev (%p), no host (%p), or "
+                         "%s: No dev (%p), or "
                          "RESET PENDING: domain_device=%p\n",
-                         __func__, isci_device, isci_host, domain_device);
+                         __func__, isci_device, domain_device);
                 return TMF_RESP_FUNC_FAILED;
         }
 
         /* Send the task management part of the reset. */
         if (sas_protocol_ata(domain_device->tproto)) {
-                ret = isci_task_send_lu_reset_sata(
-                        isci_host, isci_device, lun
-                        );
+                ret = isci_task_send_lu_reset_sata(isci_host, isci_device, lun);
         } else
                 ret = isci_task_send_lu_reset_sas(isci_host, isci_device, lun);
 
@@ -1173,11 +1154,11 @@ static void isci_abort_task_process_cb(
  */
 int isci_task_abort_task(struct sas_task *task)
 {
+        struct isci_host *isci_host = dev_to_ihost(task->dev);
         DECLARE_COMPLETION_ONSTACK(aborted_io_completion);
         struct isci_request       *old_request = NULL;
         enum isci_request_status  old_state;
         struct isci_remote_device *isci_device = NULL;
-        struct isci_host          *isci_host = NULL;
         struct isci_tmf           tmf;
         int                       ret = TMF_RESP_FUNC_FAILED;
         unsigned long             flags;
@@ -1189,8 +1170,7 @@ int isci_task_abort_task(struct sas_task *task)
          * in the device, because tasks driving resets may land here
          * after completion in the core.
          */
-        old_request = isci_task_get_request_from_task(task, &isci_host,
-                                                      &isci_device);
+        old_request = isci_task_get_request_from_task(task, &isci_device);
 
         dev_dbg(&isci_host->pdev->dev,
                 "%s: task = %p\n", __func__, task);
@@ -1610,37 +1590,29 @@ u32 isci_task_ssp_request_get_response_data_length(
  */
 int isci_bus_reset_handler(struct scsi_cmnd *cmd)
 {
+        struct domain_device *dev = cmd_to_domain_dev(cmd);
+        struct isci_host *isci_host = dev_to_ihost(dev);
         unsigned long flags = 0;
-        struct isci_host *isci_host = NULL;
         enum sci_status status;
         int base_status;
-        struct isci_remote_device *isci_dev
-                = isci_dev_from_domain_dev(
-                sdev_to_domain_dev(cmd->device));
+        struct isci_remote_device *isci_dev = dev->lldd_dev;
 
-        dev_dbg(&cmd->device->sdev_gendev,
+        dev_dbg(&isci_host->pdev->dev,
                 "%s: cmd %p, isci_dev %p\n",
                 __func__, cmd, isci_dev);
 
         if (!isci_dev) {
-                dev_warn(&cmd->device->sdev_gendev,
+                dev_warn(&isci_host->pdev->dev,
                          "%s: isci_dev is GONE!\n",
                          __func__);
 
                 return TMF_RESP_FUNC_COMPLETE; /* Nothing to reset. */
         }
 
-        if (isci_dev->isci_port != NULL)
-                isci_host = isci_dev->isci_port->isci_host;
-
-        if (isci_host != NULL)
-                spin_lock_irqsave(&isci_host->scic_lock, flags);
-
+        spin_lock_irqsave(&isci_host->scic_lock, flags);
         status = scic_remote_device_reset(to_sci_dev(isci_dev));
         if (status != SCI_SUCCESS) {
-
-                if (isci_host != NULL)
-                        spin_unlock_irqrestore(&isci_host->scic_lock, flags);
+                spin_unlock_irqrestore(&isci_host->scic_lock, flags);
 
                 scmd_printk(KERN_WARNING, cmd,
                             "%s: scic_remote_device_reset(%p) returned %d!\n",
@@ -1648,14 +1620,13 @@ int isci_bus_reset_handler(struct scsi_cmnd *cmd)
 
                 return TMF_RESP_FUNC_FAILED;
         }
-        if (isci_host != NULL)
-                spin_unlock_irqrestore(&isci_host->scic_lock, flags);
+        spin_unlock_irqrestore(&isci_host->scic_lock, flags);
 
         /* Make sure all pending requests are able to be fully terminated. */
-        isci_device_clear_reset_pending(isci_dev);
+        isci_device_clear_reset_pending(isci_host, isci_dev);
 
         /* Terminate in-progress I/O now. */
-        isci_remote_device_nuke_requests(isci_dev);
+        isci_remote_device_nuke_requests(isci_host, isci_dev);
 
         /* Call into the libsas default handler (which calls sas_phy_reset). */
         base_status = sas_eh_bus_reset_handler(cmd);
@@ -1672,13 +1643,9 @@ int isci_bus_reset_handler(struct scsi_cmnd *cmd)
         }
 
         /* WHAT TO DO HERE IF sas_phy_reset FAILS? */
-
-        if (isci_host != NULL)
-                spin_lock_irqsave(&isci_host->scic_lock, flags);
+        spin_lock_irqsave(&isci_host->scic_lock, flags);
         status = scic_remote_device_reset_complete(to_sci_dev(isci_dev));
-
-        if (isci_host != NULL)
-                spin_unlock_irqrestore(&isci_host->scic_lock, flags);
+        spin_unlock_irqrestore(&isci_host->scic_lock, flags);
 
         if (status != SCI_SUCCESS) {
                 scmd_printk(KERN_WARNING, cmd,
@@ -1688,7 +1655,7 @@ int isci_bus_reset_handler(struct scsi_cmnd *cmd)
         }
         /* WHAT TO DO HERE IF scic_remote_device_reset_complete FAILS? */
 
-        dev_dbg(&cmd->device->sdev_gendev,
+        dev_dbg(&isci_host->pdev->dev,
                 "%s: cmd %p, isci_dev %p complete.\n",
                 __func__, cmd, isci_dev);