swiotlb: Use physical addresses instead of virtual in swiotlb_tbl_sync_single

This change makes it so that the sync functionality also uses physical
addresses.  This helps to further reduce the use of virt_to_phys and
phys_to_virt functions.

In order to clarify things since we now have 2 physical addresses in use
inside of swiotlb_tbl_sync_single I am renaming phys to orig_addr, and
dma_addr to tlb_addr.  This way is should be clear that orig_addr is
contained within io_orig_addr and tlb_addr is an address within the
io_tlb_addr buffer.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 4cedc28..af47e75 100644 (file)
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -433,8 +433,7 @@ xen_swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
 
        /* NOTE: We use dev_addr here, not paddr! */
        if (is_xen_swiotlb_buffer(dev_addr)) {
-               swiotlb_tbl_sync_single(hwdev, phys_to_virt(paddr), size, dir,
-                                      target);
+               swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target);
                return;
        }
 

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 291643c..e0ac98f 100644 (file)
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -47,7 +47,8 @@ extern void swiotlb_tbl_unmap_single(struct device *hwdev,
                                     phys_addr_t tlb_addr,
                                     size_t size, enum dma_data_direction dir);
 
-extern void swiotlb_tbl_sync_single(struct device *hwdev, char *dma_addr,
+extern void swiotlb_tbl_sync_single(struct device *hwdev,
+                                   phys_addr_t tlb_addr,
                                    size_t size, enum dma_data_direction dir,
                                    enum dma_sync_target target);
 

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index d7701dc..16a548d 100644 (file)
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -557,26 +557,27 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
 }
 EXPORT_SYMBOL_GPL(swiotlb_tbl_unmap_single);
 
-void
-swiotlb_tbl_sync_single(struct device *hwdev, char *dma_addr, size_t size,
-                       enum dma_data_direction dir,
-                       enum dma_sync_target target)
+void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
+                            size_t size, enum dma_data_direction dir,
+                            enum dma_sync_target target)
 {
-       int index = (dma_addr - (char *)phys_to_virt(io_tlb_start)) >> IO_TLB_SHIFT;
-       phys_addr_t phys = io_tlb_orig_addr[index];
+       int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
+       phys_addr_t orig_addr = io_tlb_orig_addr[index];
 
-       phys += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1));
+       orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1);
 
        switch (target) {
        case SYNC_FOR_CPU:
                if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
-                       swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE);
+                       swiotlb_bounce(orig_addr, phys_to_virt(tlb_addr),
+                                      size, DMA_FROM_DEVICE);
                else
                        BUG_ON(dir != DMA_TO_DEVICE);
                break;
        case SYNC_FOR_DEVICE:
                if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
-                       swiotlb_bounce(phys, dma_addr, size, DMA_TO_DEVICE);
+                       swiotlb_bounce(orig_addr, phys_to_virt(tlb_addr),
+                                      size, DMA_TO_DEVICE);
                else
                        BUG_ON(dir != DMA_FROM_DEVICE);
                break;
@@ -785,8 +786,7 @@ swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
        BUG_ON(dir == DMA_NONE);
 
        if (is_swiotlb_buffer(paddr)) {
-               swiotlb_tbl_sync_single(hwdev, phys_to_virt(paddr), size, dir,
-                                      target);
+               swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target);
                return;
        }