Merge branch 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel...

Pull swiotlb updates from Konrad Rzeszutek Wilk:
 "Two tiny implementations of the DMA API for callback in ARM (for Xen)"

* 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  swiotlb-xen: implement xen_swiotlb_get_sgtable callback
  swiotlb-xen: implement xen_swiotlb_dma_mmap callback

diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
index ce18c91b50a1cbac3fb6d38af60c63af9b031185..f0325d96b97aed734f86deb3a9f5b3266b5a16ed 100644 (file)
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -198,6 +198,8 @@ static const 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,
+       .get_sgtable = xen_swiotlb_get_sgtable,
 };
 
 int __init xen_mm_init(void)

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index f8afc6dcc29f2769694308092a4b543e5e0bed49..e8cef1ad0fe31e0139903399d70730c7eafdc399 100644 (file)
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -681,3 +681,50 @@ xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask)
        return 0;
 }
 EXPORT_SYMBOL_GPL(xen_swiotlb_set_dma_mask);
+
+/*
+ * Create userspace mapping for the DMA-coherent memory.
+ * This function should be called with the pages from the current domain only,
+ * passing pages mapped from other domains would lead to memory corruption.
+ */
+int
+xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+                    void *cpu_addr, dma_addr_t dma_addr, size_t size,
+                    unsigned long attrs)
+{
+#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
+       if (__generic_dma_ops(dev)->mmap)
+               return __generic_dma_ops(dev)->mmap(dev, vma, cpu_addr,
+                                                   dma_addr, size, attrs);
+#endif
+       return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mmap);
+
+/*
+ * This function should be called with the pages from the current domain only,
+ * passing pages mapped from other domains would lead to memory corruption.
+ */
+int
+xen_swiotlb_get_sgtable(struct device *dev, struct sg_table *sgt,
+                       void *cpu_addr, dma_addr_t handle, size_t size,
+                       unsigned long attrs)
+{
+#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
+       if (__generic_dma_ops(dev)->get_sgtable) {
+#if 0
+       /*
+        * This check verifies that the page belongs to the current domain and
+        * is not one mapped from another domain.
+        * This check is for debug only, and should not go to production build
+        */
+               unsigned long bfn = PHYS_PFN(dma_to_phys(dev, handle));
+               BUG_ON (!page_is_ram(bfn));
+#endif
+               return __generic_dma_ops(dev)->get_sgtable(dev, sgt, cpu_addr,
+                                                          handle, size, attrs);
+       }
+#endif
+       return dma_common_get_sgtable(dev, sgt, cpu_addr, handle, size);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_get_sgtable);

diff --git a/include/xen/swiotlb-xen.h b/include/xen/swiotlb-xen.h
index a0083be5d5295157bc11b82a343b58f798488bb8..1f6d78f044b671bca827b15c5b6b8388c09e4fa6 100644 (file)
--- a/include/xen/swiotlb-xen.h
+++ b/include/xen/swiotlb-xen.h
@@ -2,6 +2,7 @@
 #define __LINUX_SWIOTLB_XEN_H
 
 #include <linux/dma-direction.h>
+#include <linux/scatterlist.h>
 #include <linux/swiotlb.h>
 
 extern int xen_swiotlb_init(int verbose, bool early);
@@ -55,4 +56,14 @@ xen_swiotlb_dma_supported(struct device *hwdev, u64 mask);
 
 extern int
 xen_swiotlb_set_dma_mask(struct device *dev, u64 dma_mask);
+
+extern int
+xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+                    void *cpu_addr, dma_addr_t dma_addr, size_t size,
+                    unsigned long attrs);
+
+extern int
+xen_swiotlb_get_sgtable(struct device *dev, struct sg_table *sgt,
+                       void *cpu_addr, dma_addr_t handle, size_t size,
+                       unsigned long attrs);
 #endif /* __LINUX_SWIOTLB_XEN_H */