isci: fix dma_unmap_sg usage

One bug and a cleanup:
1/ Fix cases where we were unmapping invalid addresses (smp requests were
   being unmapped)

[  604.662770] ------------[ cut here ]------------
[  604.668026] WARNING: at lib/dma-debug.c:800 check_unmap+0x418/0x740()
[  604.675315] Hardware name: SandyBridge Platform
[  604.680465] isci 0000:03:00.0: DMA-API: device driver tries to free an invalid DMA memory address

2/ The unmap routine is too large to be an inline function, and
   isci_request_io_request_get_next_sge is unused.

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

2 files changed, 18 insertions, 90 deletions

diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
index f4fbca7b1fa3..395084955150 100644
--- a/drivers/scsi/isci/request.c
+++ b/drivers/scsi/isci/request.c
@@ -2930,7 +2930,22 @@ static void isci_request_io_request_complete(struct isci_host *isci_host,
                 break;
         }
 
-        isci_request_unmap_sgl(request, isci_host->pdev);
+        switch (task->task_proto) {
+        case SAS_PROTOCOL_SSP:
+                if (task->data_dir == DMA_NONE)
+                        break;
+                if (task->num_scatter == 0)
+                        /* 0 indicates a single dma address */
+                        dma_unmap_single(&isci_host->pdev->dev,
+                                         request->zero_scatter_daddr,
+                                         task->total_xfer_len, task->data_dir);
+                else  /* unmap the sgl dma addresses */
+                        dma_unmap_sg(&isci_host->pdev->dev, task->scatter,
+                                     request->num_sg_entries, task->data_dir);
+                break;
+        default:
+                break;
+        }
 
         /* Put the completed request on the correct list */
         isci_task_save_for_upper_layer_completion(isci_host, request, response,
diff --git a/drivers/scsi/isci/request.h b/drivers/scsi/isci/request.h
index a91d1d6060ce..324fb7b3ab42 100644
--- a/drivers/scsi/isci/request.h
+++ b/drivers/scsi/isci/request.h
@@ -672,97 +672,10 @@ static inline void isci_request_free(struct isci_host *isci_host,
 struct isci_request *isci_request_alloc_tmf(struct isci_host *ihost,
                                             struct isci_tmf *isci_tmf,
                                             gfp_t gfp_flags);
-
 int isci_request_execute(struct isci_host *ihost, struct isci_remote_device *idev,
                          struct sas_task *task, gfp_t gfp_flags);
-
-/**
- * isci_request_unmap_sgl() - This function unmaps the DMA address of a given
- *    sgl
- * @request: This parameter points to the isci_request object
- * @*pdev: This Parameter is the pci_device struct for the controller
- *
- */
-static inline void
-isci_request_unmap_sgl(struct isci_request *request, struct pci_dev *pdev)
-{
-        struct sas_task *task = isci_request_access_task(request);
-
-        dev_dbg(&request->isci_host->pdev->dev,
-                "%s: request = %p, task = %p,\n"
-                "task->data_dir = %d, is_sata = %d\n ",
-                __func__,
-                request,
-                task,
-                task->data_dir,
-                sas_protocol_ata(task->task_proto));
-
-        if ((task->data_dir != PCI_DMA_NONE) &&
-            !sas_protocol_ata(task->task_proto)) {
-                if (task->num_scatter == 0)
-                        /* 0 indicates a single dma address */
-                        dma_unmap_single(
-                                &pdev->dev,
-                                request->zero_scatter_daddr,
-                                task->total_xfer_len,
-                                task->data_dir
-                                );
-
-                else  /* unmap the sgl dma addresses */
-                        dma_unmap_sg(
-                                &pdev->dev,
-                                task->scatter,
-                                request->num_sg_entries,
-                                task->data_dir
-                                );
-        }
-}
-
-/**
- * isci_request_io_request_get_next_sge() - This function is called by the sci
- *    core to retrieve the next sge for a given request.
- * @request: This parameter is the isci_request object.
- * @current_sge_address: This parameter is the last sge retrieved by the sci
- *    core for this request.
- *
- * pointer to the next sge for specified request.
- */
-static inline void *
-isci_request_io_request_get_next_sge(struct isci_request *request,
-                                     void *current_sge_address)
-{
-        struct sas_task *task = isci_request_access_task(request);
-        void *ret = NULL;
-
-        dev_dbg(&request->isci_host->pdev->dev,
-                "%s: request = %p, "
-                "current_sge_address = %p, "
-                "num_scatter = %d\n",
-                __func__,
-                request,
-                current_sge_address,
-                task->num_scatter);
-
-        if (!current_sge_address)       /* First time through.. */
-                ret = task->scatter;    /* always task->scatter */
-        else if (task->num_scatter == 0) /* Next element, if num_scatter == 0 */
-                ret = NULL;              /* there is only one element. */
-        else
-                ret = sg_next(current_sge_address);     /* sg_next returns NULL
-                                                         * for the last element
-                                                         */
-
-        dev_dbg(&request->isci_host->pdev->dev,
-                "%s: next sge address = %p\n",
-                __func__,
-                ret);
-
-        return ret;
-}
-
-void
-isci_terminate_pending_requests(struct isci_host *ihost,
-                                struct isci_remote_device *idev);
+void isci_terminate_pending_requests(struct isci_host *ihost,
+                                     struct isci_remote_device *idev);
 enum sci_status
 scic_task_request_construct(struct scic_sds_controller *scic,
                             struct scic_sds_remote_device *sci_dev,