hw/xen: Add foreignmem operations to allow redirection to internal emulation

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>

1 files changed, 26 insertions, 0 deletions

diff --git a/include/hw/xen/xen_backend_ops.h b/include/hw/xen/xen_backend_ops.h
index 6f9d8e2c62..0dff06bbde 100644
--- a/include/hw/xen/xen_backend_ops.h
+++ b/include/hw/xen/xen_backend_ops.h
@@ -214,6 +214,32 @@ static inline int qemu_xen_gnttab_unmap(xengnttab_handle *xgt,
     return xen_gnttab_ops->unmap(xgt, start_address, refs, count);
 }
 
+struct foreignmem_backend_ops {
+    void *(*map)(uint32_t dom, void *addr, int prot, size_t pages,
+                 xen_pfn_t *pfns, int *errs);
+    int (*unmap)(void *addr, size_t pages);
+};
+
+extern struct foreignmem_backend_ops *xen_foreignmem_ops;
+
+static inline void *qemu_xen_foreignmem_map(uint32_t dom, void *addr, int prot,
+                                            size_t pages, xen_pfn_t *pfns,
+                                            int *errs)
+{
+    if (!xen_foreignmem_ops) {
+        return NULL;
+    }
+    return xen_foreignmem_ops->map(dom, addr, prot, pages, pfns, errs);
+}
+
+static inline int qemu_xen_foreignmem_unmap(void *addr, size_t pages)
+{
+    if (!xen_foreignmem_ops) {
+        return -ENOSYS;
+    }
+    return xen_foreignmem_ops->unmap(addr, pages);
+}
+
 void setup_xen_backend_ops(void);
 
 #endif /* QEMU_XEN_BACKEND_OPS_H */