Merge branch 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
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 ce18c91..f0325d9 100644
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -198,6 +198,8 @@
.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 f8afc6d..e8cef1a 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -681,3 +681,50 @@
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 a0083be..1f6d78f 100644
--- 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 @@
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 */