Fix grant-table interface by removing the unnecessary union.

This fixes a domU crash introduced over the weekend.
Signed-off-by: Keir Fraser <keir@xensource.com>

1 files changed, 37 insertions, 38 deletions

diff --git a/tools/libxc/xc_gnttab.c b/tools/libxc/xc_gnttab.c
index 409539cb14..4101ca74dd 100644
--- a/tools/libxc/xc_gnttab.c
+++ b/tools/libxc/xc_gnttab.c
@@ -11,20 +11,20 @@
 #include "xen/grant_table.h"
 
 static int
-do_gnttab_op( int xc_handle,
-              unsigned long cmd,
-              gnttab_op_t *op,
-              unsigned long count )
+do_gnttab_op(int xc_handle,
+             unsigned long cmd,
+             void *op,
+             unsigned long count)
 {
     int ret = -1;
     privcmd_hypercall_t hypercall;
 
     hypercall.op     = __HYPERVISOR_grant_table_op;
     hypercall.arg[0] = cmd;
-    hypercall.arg[1] = (unsigned long)(op);
+    hypercall.arg[1] = (unsigned long)op;
     hypercall.arg[2] = count;
 
-    if ( mlock(op, sizeof(*op)) != 0 )
+    if ( mlock(op, 64) )
     {
         PERROR("do_gnttab_op: op mlock failed");
         goto out;
@@ -33,7 +33,7 @@ do_gnttab_op( int xc_handle,
     if ( (ret = do_xen_hypercall(xc_handle, &hypercall)) < 0 )
         ERROR("do_gnttab_op: HYPERVISOR_grant_table_op failed: %d", ret);
 
-    safe_munlock(op, sizeof(*op));
+    safe_munlock(op, 64);
  out:
     return ret;
 }
@@ -47,18 +47,19 @@ int xc_gnttab_map_grant_ref(int         xc_handle,
                             s16        *handle,
                             memory_t   *dev_bus_addr)
 {
-    gnttab_op_t     op;
-    int             rc;
+    struct gnttab_map_grant_ref op;
+    int rc;
 
-    op.u.map_grant_ref.host_virt_addr = host_virt_addr;
-    op.u.map_grant_ref.dom            = (domid_t)dom;
-    op.u.map_grant_ref.ref            = ref;
-    op.u.map_grant_ref.flags          = flags;
+    op.host_virt_addr = host_virt_addr;
+    op.dom            = (domid_t)dom;
+    op.ref            = ref;
+    op.flags          = flags;
  
-    if ( (rc = do_gnttab_op(xc_handle, GNTTABOP_map_grant_ref, &op, 1)) == 0 )
+    if ( (rc = do_gnttab_op(xc_handle, GNTTABOP_map_grant_ref,
+                            &op, 1)) == 0 )
     {
-        *handle         = op.u.map_grant_ref.handle;
-        *dev_bus_addr   = op.u.map_grant_ref.dev_bus_addr;
+        *handle         = op.handle;
+        *dev_bus_addr   = op.dev_bus_addr;
     }
 
     return rc;
@@ -71,15 +72,18 @@ int xc_gnttab_unmap_grant_ref(int       xc_handle,
                               u16       handle,
                               s16      *status)
 {
-    gnttab_op_t     op;
-    int             rc;
+    struct gnttab_unmap_grant_ref op;
+    int rc;
 
-    op.u.unmap_grant_ref.host_virt_addr = host_virt_addr;
-    op.u.unmap_grant_ref.dev_bus_addr   = dev_bus_addr;
-    op.u.unmap_grant_ref.handle         = handle;
+    op.host_virt_addr = host_virt_addr;
+    op.dev_bus_addr   = dev_bus_addr;
+    op.handle         = handle;
  
-    if ( (rc = do_gnttab_op(xc_handle, GNTTABOP_unmap_grant_ref, &op, 1)) == 0 )
-        *status = op.u.unmap_grant_ref.status;
+    if ( (rc = do_gnttab_op(xc_handle, GNTTABOP_unmap_grant_ref,
+                            &op, 1)) == 0 )
+    {
+        *status = op.status;
+    }
 
     return rc;
 }
@@ -90,20 +94,17 @@ int xc_gnttab_setup_table(int        xc_handle,
                           s16       *status,
                           memory_t **frame_list)
 {
-    gnttab_op_t     op;
-    int             rc;
-    int             i;
+    struct gnttab_setup_table op;
+    int rc, i;
 
-    op.u.setup_table.dom        = (domid_t)dom;
-    op.u.setup_table.nr_frames  = nr_frames;
+    op.dom       = (domid_t)dom;
+    op.nr_frames = nr_frames;
  
     if ( (rc = do_gnttab_op(xc_handle, GNTTABOP_setup_table, &op, 1)) == 0 )
     {
-        *status = op.u.setup_table.status;
+        *status = op.status;
         for ( i = 0; i < nr_frames; i++ )
-        {
-            (*frame_list)[i] = op.u.setup_table.frame_list[i];
-        }
+            (*frame_list)[i] = op.frame_list[i];
     }
 
     return rc;
@@ -113,15 +114,13 @@ int xc_gnttab_dump_table(int        xc_handle,
                          u32        dom,
                          s16       *status)
 {
-    gnttab_op_t     op;
-    int             rc;
+    struct gnttab_dump_table op;
+    int rc;
 
-    op.u.dump_table.dom = (domid_t)dom;
- 
-    printf("xc_gnttab_dump_table: domain %d\n", dom);
+    op.dom = (domid_t)dom;
 
     if ( (rc = do_gnttab_op(xc_handle, GNTTABOP_dump_table, &op, 1)) == 0 )
-        *status = op.u.dump_table.status;
+        *status = op.status;
 
     return rc;
 }