1 files changed, 40 insertions, 22 deletions

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 566791b3f583..a1a6d6bf87b4 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -58,6 +58,14 @@
  */
 #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
 
+/*
+ * Enumeration for sync targets
+ */
+enum dma_sync_target {
+        SYNC_FOR_CPU = 0,
+        SYNC_FOR_DEVICE = 1,
+};
+
 int swiotlb_force;
 
 /*
@@ -397,21 +405,28 @@ unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
 }
 
 static void
-sync_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
+sync_single(struct device *hwdev, char *dma_addr, size_t size,
+            int dir, int target)
 {
         int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
         char *buffer = io_tlb_orig_addr[index];
 
-        /*
-         * bounce... copy the data back into/from the original buffer
-         * XXX How do you handle DMA_BIDIRECTIONAL here ?
-         */
-        if (dir == DMA_FROM_DEVICE)
-                memcpy(buffer, dma_addr, size);
-        else if (dir == DMA_TO_DEVICE)
-                memcpy(dma_addr, buffer, size);
-        else
+        switch (target) {
+        case SYNC_FOR_CPU:
+                if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
+                        memcpy(buffer, dma_addr, size);
+                else if (dir != DMA_TO_DEVICE)
+                        BUG();
+                break;
+        case SYNC_FOR_DEVICE:
+                if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
+                        memcpy(dma_addr, buffer, size);
+                else if (dir != DMA_FROM_DEVICE)
+                        BUG();
+                break;
+        default:
                 BUG();
+        }
 }
 
 void *
@@ -596,14 +611,14 @@ swiotlb_unmap_single(struct device *hwdev, dma_addr_t dev_addr, size_t size,
  */
 static inline void
 swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
-                    size_t size, int dir)
+                    size_t size, int dir, int target)
 {
         char *dma_addr = phys_to_virt(dev_addr);
 
         if (dir == DMA_NONE)
                 BUG();
         if (dma_addr >= io_tlb_start && dma_addr < io_tlb_end)
-                sync_single(hwdev, dma_addr, size, dir);
+                sync_single(hwdev, dma_addr, size, dir, target);
         else if (dir == DMA_FROM_DEVICE)
                 mark_clean(dma_addr, size);
 }
@@ -612,14 +627,14 @@ void
 swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
                             size_t size, int dir)
 {
-        swiotlb_sync_single(hwdev, dev_addr, size, dir);
+        swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
 }
 
 void
 swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
                                size_t size, int dir)
 {
-        swiotlb_sync_single(hwdev, dev_addr, size, dir);
+        swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
 }
 
 /*
@@ -627,14 +642,15 @@ swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
  */
 static inline void
 swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr,
-                          unsigned long offset, size_t size, int dir)
+                          unsigned long offset, size_t size,
+                          int dir, int target)
 {
         char *dma_addr = phys_to_virt(dev_addr) + offset;
 
         if (dir == DMA_NONE)
                 BUG();
         if (dma_addr >= io_tlb_start && dma_addr < io_tlb_end)
-                sync_single(hwdev, dma_addr, size, dir);
+                sync_single(hwdev, dma_addr, size, dir, target);
         else if (dir == DMA_FROM_DEVICE)
                 mark_clean(dma_addr, size);
 }
@@ -643,14 +659,16 @@ void
 swiotlb_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
                                   unsigned long offset, size_t size, int dir)
 {
-        swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir);
+        swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
+                                  SYNC_FOR_CPU);
 }
 
 void
 swiotlb_sync_single_range_for_device(struct device *hwdev, dma_addr_t dev_addr,
                                      unsigned long offset, size_t size, int dir)
 {
-        swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir);
+        swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
+                                  SYNC_FOR_DEVICE);
 }
 
 /*
@@ -729,7 +747,7 @@ swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sg, int nelems,
  */
 static inline void
 swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sg,
-                int nelems, int dir)
+                int nelems, int dir, int target)
 {
         int i;
 
@@ -739,21 +757,21 @@ swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sg,
         for (i = 0; i < nelems; i++, sg++)
                 if (sg->dma_address != SG_ENT_PHYS_ADDRESS(sg))
                         sync_single(hwdev, (void *) sg->dma_address,
-                                    sg->dma_length, dir);
+                                    sg->dma_length, dir, target);
 }
 
 void
 swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
                         int nelems, int dir)
 {
-        swiotlb_sync_sg(hwdev, sg, nelems, dir);
+        swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
 }
 
 void
 swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
                            int nelems, int dir)
 {
-        swiotlb_sync_sg(hwdev, sg, nelems, dir);
+        swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
 }
 
 int