summaryrefslogtreecommitdiffstats
path: root/arch/arm/xen/mm.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/xen/mm.c')
-rw-r--r--arch/arm/xen/mm.c61
1 files changed, 21 insertions, 40 deletions
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
index 90574d89d0d4..2fde161733b0 100644
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -35,64 +35,45 @@ unsigned long xen_get_swiotlb_free_pages(unsigned int order)
return __get_free_pages(flags, order);
}
-enum dma_cache_op {
- DMA_UNMAP,
- DMA_MAP,
-};
static bool hypercall_cflush = false;
-/* functions called by SWIOTLB */
-
-static void dma_cache_maint(dma_addr_t handle, unsigned long offset,
- size_t size, enum dma_data_direction dir, enum dma_cache_op op)
+/* buffers in highmem or foreign pages cannot cross page boundaries */
+static void dma_cache_maint(dma_addr_t handle, size_t size, u32 op)
{
struct gnttab_cache_flush cflush;
- unsigned long xen_pfn;
- size_t left = size;
- xen_pfn = (handle >> XEN_PAGE_SHIFT) + offset / XEN_PAGE_SIZE;
- offset %= XEN_PAGE_SIZE;
+ cflush.a.dev_bus_addr = handle & XEN_PAGE_MASK;
+ cflush.offset = xen_offset_in_page(handle);
+ cflush.op = op;
do {
- size_t len = left;
-
- /* buffers in highmem or foreign pages cannot cross page
- * boundaries */
- if (len + offset > XEN_PAGE_SIZE)
- len = XEN_PAGE_SIZE - offset;
-
- cflush.op = 0;
- cflush.a.dev_bus_addr = xen_pfn << XEN_PAGE_SHIFT;
- cflush.offset = offset;
- cflush.length = len;
-
- if (op == DMA_UNMAP && dir != DMA_TO_DEVICE)
- cflush.op = GNTTAB_CACHE_INVAL;
- if (op == DMA_MAP) {
- if (dir == DMA_FROM_DEVICE)
- cflush.op = GNTTAB_CACHE_INVAL;
- else
- cflush.op = GNTTAB_CACHE_CLEAN;
- }
- if (cflush.op)
- HYPERVISOR_grant_table_op(GNTTABOP_cache_flush, &cflush, 1);
+ if (size + cflush.offset > XEN_PAGE_SIZE)
+ cflush.length = XEN_PAGE_SIZE - cflush.offset;
+ else
+ cflush.length = size;
+
+ HYPERVISOR_grant_table_op(GNTTABOP_cache_flush, &cflush, 1);
- offset = 0;
- xen_pfn++;
- left -= len;
- } while (left);
+ cflush.offset = 0;
+ cflush.a.dev_bus_addr += cflush.length;
+ size -= cflush.length;
+ } while (size);
}
static void __xen_dma_page_dev_to_cpu(struct device *hwdev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
- dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_UNMAP);
+ if (dir != DMA_TO_DEVICE)
+ dma_cache_maint(handle, size, GNTTAB_CACHE_INVAL);
}
static void __xen_dma_page_cpu_to_dev(struct device *hwdev, dma_addr_t handle,
size_t size, enum dma_data_direction dir)
{
- dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_MAP);
+ if (dir == DMA_FROM_DEVICE)
+ dma_cache_maint(handle, size, GNTTAB_CACHE_INVAL);
+ else
+ dma_cache_maint(handle, size, GNTTAB_CACHE_CLEAN);
}
void __xen_dma_map_page(struct device *hwdev, struct page *page,