Tools: Libxc wrappers to automatically fill in page oud page contents on prepare

Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Tim Deegan <tim@xen.org>

1 files changed, 23 insertions, 0 deletions

diff --git a/tools/libxc/xc_mem_paging.c b/tools/libxc/xc_mem_paging.c
index f917403b39..f16d16b3ab 100644
--- a/tools/libxc/xc_mem_paging.c
+++ b/tools/libxc/xc_mem_paging.c
@@ -65,6 +65,29 @@ int xc_mem_paging_prep(xc_interface *xch, domid_t domain_id, unsigned long gfn)
                                 NULL, NULL, gfn);
 }
 
+int xc_mem_paging_load(xc_interface *xch, domid_t domain_id, 
+                                unsigned long gfn, void *buffer)
+{
+    int rc;
+
+    if ( !buffer )
+        return -EINVAL;
+
+    if ( ((unsigned long) buffer) & (XC_PAGE_SIZE - 1) )
+        return -EINVAL;
+
+    if ( mlock(buffer, XC_PAGE_SIZE) )
+        return -errno;
+        
+    rc = xc_mem_event_control(xch, domain_id,
+                                XEN_DOMCTL_MEM_EVENT_OP_PAGING_PREP,
+                                XEN_DOMCTL_MEM_EVENT_OP_PAGING,
+                                buffer, NULL, gfn);
+
+    (void)munlock(buffer, XC_PAGE_SIZE);
+    return rc;
+}
+
 int xc_mem_paging_resume(xc_interface *xch, domid_t domain_id, unsigned long gfn)
 {
     return xc_mem_event_control(xch, domain_id,