4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
commit 7e91c7df29b5e196de3dc6f086c8937973bd0b88 upstream.
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>
Signed-off-by: Konrad Rzeszutek Wilk <konrad@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm/xen/mm.c | 1 +
drivers/xen/swiotlb-xen.c | 19 +++++++++++++++++++
include/xen/swiotlb-xen.h | 5 +++++
3 files changed, 25 insertions(+)
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -199,6 +199,7 @@ static struct dma_map_ops xen_swiotlb_dm
.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)
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -680,3 +680,22 @@ xen_swiotlb_set_dma_mask(struct device *
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);
--- a/include/xen/swiotlb-xen.h
+++ b/include/xen/swiotlb-xen.h
@@ -58,4 +58,9 @@ xen_swiotlb_dma_supported(struct device
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);
#endif /* __LINUX_SWIOTLB_XEN_H */