minios: grant table map (gntdev) bug fixes

 * Uninitialized dev_bus_addr argument to GNTTABOP_unmap_grant_ref
   results in an angry hypervisor.
 * Set errno in libxc and return -1 on error.
 * op.status is a int16_t, so it should be printed with PRId16.
 * Don't print domids[0] or refs[0] if the ptr is NULL. It's more
   polite to crash later, after the message has been printed.

Signed-off-by: Diego Ongaro <diego.ongaro@citrix.com>

1 files changed, 17 insertions, 5 deletions

diff --git a/tools/libxc/xc_minios.c b/tools/libxc/xc_minios.c
index f0c383bfd8..3781907d15 100644
--- a/tools/libxc/xc_minios.c
+++ b/tools/libxc/xc_minios.c
@@ -383,16 +383,28 @@ int xc_gnttab_munmap(int xcg_handle,
                      void *start_address,
                      uint32_t count)
 {
-    return gntmap_munmap(&files[xcg_handle].gntmap,
-                         (unsigned long) start_address,
-                         count);
+    int ret;
+    ret = gntmap_munmap(&files[xcg_handle].gntmap,
+                        (unsigned long) start_address,
+                        count);
+    if (ret < 0) {
+        errno = -ret;
+        return -1;
+    }
+    return ret;
 }
 
 int xc_gnttab_set_max_grants(int xcg_handle,
                              uint32_t count)
 {
-    return gntmap_set_max_grants(&files[xcg_handle].gntmap,
-                                 count);
+    int ret;
+    ret = gntmap_set_max_grants(&files[xcg_handle].gntmap,
+                                count);
+    if (ret < 0) {
+        errno = -ret;
+        return -1;
+    }
+    return ret;
 }
 
 /*