xen/gntdev: Add initial support for dma-buf UAPI
Add UAPI and IOCTLs for dma-buf grant device driver extension:
the extension allows userspace processes and kernel modules to
use Xen backed dma-buf implementation. With this extension grant
references to the pages of an imported dma-buf can be exported
for other domain use and grant references coming from a foreign
domain can be converted into a local dma-buf for local export.
Implement basic initialization and stubs for Xen DMA buffers'
support.
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
diff --git a/drivers/xen/gntdev-common.h b/drivers/xen/gntdev-common.h
index 2346c19..2f8b949 100644
--- a/drivers/xen/gntdev-common.h
+++ b/drivers/xen/gntdev-common.h
@@ -16,6 +16,8 @@
#include <linux/mmu_notifier.h>
#include <linux/types.h>
+struct gntdev_dmabuf_priv;
+
struct gntdev_priv {
/* Maps with visible offsets in the file descriptor. */
struct list_head maps;
@@ -33,6 +35,10 @@ struct gntdev_priv {
/* Device for which DMA memory is allocated. */
struct device *dma_dev;
#endif
+
+#ifdef CONFIG_XEN_GNTDEV_DMABUF
+ struct gntdev_dmabuf_priv *dmabuf_priv;
+#endif
};
struct gntdev_unmap_notify {