xen/grant-table: add error-handling code on failure of gnttab_resume

Jump to the label ini_nomem as done on the failure of the page allocations
above.

The code at ini_nomem is modified to accommodate different return values.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

drivers/xen/grant-table.c

@@ -1026,6 +1026,7 @@ int gnttab_init(void)
 	int i;
 	unsigned int max_nr_glist_frames, nr_glist_frames;
 	unsigned int nr_init_grefs;
+	int ret;
 
 	nr_grant_frames = 1;
 	boot_max_nr_grant_frames = __max_nr_grant_frames();
@@ -1044,12 +1045,16 @@ int gnttab_init(void)
 	nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP;
 	for (i = 0; i < nr_glist_frames; i++) {
 		gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL);
-		if (gnttab_list[i] == NULL)
+		if (gnttab_list[i] == NULL) {
+			ret = -ENOMEM;
 			goto ini_nomem;
+		}
 	}
 
-	if (gnttab_resume() < 0)
-		return -ENODEV;
+	if (gnttab_resume() < 0) {
+		ret = -ENODEV;
+		goto ini_nomem;
+	}
 
 	nr_init_grefs = nr_grant_frames * GREFS_PER_GRANT_FRAME;
 
@@ -1067,7 +1072,7 @@ int gnttab_init(void)
 	for (i--; i >= 0; i--)
 		free_page((unsigned long)gnttab_list[i]);
 	kfree(gnttab_list);
-	return -ENOMEM;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(gnttab_init);