vfio: introduce vfio_dma_rw to read/write a range of IOVAs
vfio_dma_rw will read/write a range of user space memory pointed to by
IOVA into/from a kernel buffer without enforcing pinning the user space
memory.
TODO: mark the IOVAs to user space memory dirty if they are written in
vfio_dma_rw().
Cc: Kevin Tian <[email protected]>
Signed-off-by: Yan Zhao <[email protected]>
Signed-off-by: Alex Williamson <[email protected]>
diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index fb71e0a..34b2fdf 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -82,6 +82,8 @@ struct vfio_iommu_driver_ops {
struct notifier_block *nb);
int (*unregister_notifier)(void *iommu_data,
struct notifier_block *nb);
+ int (*dma_rw)(void *iommu_data, dma_addr_t user_iova,
+ void *data, size_t count, bool write);
};
extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
@@ -109,6 +111,9 @@ extern int vfio_pin_pages(struct device *dev, unsigned long *user_pfn,
extern int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn,
int npage);
+extern int vfio_dma_rw(struct vfio_group *group, dma_addr_t user_iova,
+ void *data, size_t len, bool write);
+
/* each type has independent events */
enum vfio_notify_type {
VFIO_IOMMU_NOTIFY = 0,
