[Xen-devel] [RFC 1/2] swiotlb-xen: implement xen_swiotlb_dma_mmap callback

[Andrii Anisov <andrii.anisov@xxxxxxxxx>]

From: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>

This function creates userspace mapping for the DMA-coherent memory.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
Signed-off-by: Oleksandr Dmytryshyn <oleksandr.dmytryshyn@xxxxxxxxxxxxxxx>
Signed-off-by: Andrii Anisov <andrii_anisov@xxxxxxxx>
---
 arch/arm/xen/mm.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
index c5f9a9e..050cf34 100644
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -163,6 +163,19 @@ bool xen_arch_need_swiotlb(struct device *dev,
                !is_device_dma_coherent(dev));
 }
 
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ */
+static int xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+                        void *cpu_addr, dma_addr_t dma_addr, size_t size,
+                        struct dma_attrs *attrs)
+{
+       if (__generic_dma_ops(dev)->mmap)
+               return __generic_dma_ops(dev)->mmap(dev, vma, cpu_addr, 
dma_addr, size, attrs);
+
+       return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+
 int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order,
                                 unsigned int address_bits,
                                 dma_addr_t *dma_handle)
@@ -199,6 +212,7 @@ static struct dma_map_ops xen_swiotlb_dma_ops = {
        .unmap_page = xen_swiotlb_unmap_page,
        .dma_supported = xen_swiotlb_dma_supported,
        .set_dma_mask = xen_swiotlb_set_dma_mask,
+       .mmap = xen_swiotlb_dma_mmap,
 };
 
 int __init xen_mm_init(void)
-- 
2.7.4


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel