Define wrapper functions vm_map_entry_{succ,pred} to act as wrappers

around entry->{next,prev} when those are used for ordered list
traversal, and use those wrapper functions everywhere. Where the next
field is used for maintaining a stack of deferred operations, #define
defer_next to make that different usage clearer, and then use the
'right' pointer instead of 'next' for that purpose.

Approved by: markj
Tested by: pho (as part of a larger patch)
Differential Revision: https://reviews.freebsd.org/D22347

1 files changed, 16 insertions, 1 deletions

diff --git a/sys/vm/vm_map.h b/sys/vm/vm_map.h
index d31c91822352..b4746242719a 100644
--- a/sys/vm/vm_map.h
+++ b/sys/vm/vm_map.h
@@ -419,10 +419,25 @@ int vm_map_lookup_locked(vm_map_t *, vm_offset_t, vm_prot_t, vm_map_entry_t *, v
     vm_pindex_t *, vm_prot_t *, boolean_t *);
 void vm_map_lookup_done (vm_map_t, vm_map_entry_t);
 boolean_t vm_map_lookup_entry (vm_map_t, vm_offset_t, vm_map_entry_t *);
+
+static inline vm_map_entry_t
+vm_map_entry_succ(vm_map_entry_t entry)
+{
+
+	return (entry->next);
+}
+
+static inline vm_map_entry_t
+vm_map_entry_pred(vm_map_entry_t entry)
+{
+
+	return (entry->prev);
+}
+
 #define VM_MAP_ENTRY_FOREACH(it, map)			\
 	for ((it) = (map)->header.next;		\
 	    (it) != &(map)->header;		\
-	    (it) = (it)->next)
+	    (it) = vm_map_entry_succ(it))
 int vm_map_protect (vm_map_t, vm_offset_t, vm_offset_t, vm_prot_t, boolean_t);
 int vm_map_remove (vm_map_t, vm_offset_t, vm_offset_t);
 void vm_map_try_merge_entries(vm_map_t map, vm_map_entry_t prev,