1 files changed, 24 insertions, 0 deletions

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index b62cab575a84..3171f884d245 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1359,6 +1359,30 @@ restart:
         return 0;
 }
 
+void mpol_shared_policy_init(struct shared_policy *info, int policy,
+                                nodemask_t *policy_nodes)
+{
+        info->root = RB_ROOT;
+        spin_lock_init(&info->lock);
+
+        if (policy != MPOL_DEFAULT) {
+                struct mempolicy *newpol;
+
+                /* Falls back to MPOL_DEFAULT on any error */
+                newpol = mpol_new(policy, policy_nodes);
+                if (!IS_ERR(newpol)) {
+                        /* Create pseudo-vma that contains just the policy */
+                        struct vm_area_struct pvma;
+
+                        memset(&pvma, 0, sizeof(struct vm_area_struct));
+                        /* Policy covers entire file */
+                        pvma.vm_end = TASK_SIZE;
+                        mpol_set_shared_policy(info, &pvma, newpol);
+                        mpol_free(newpol);
+                }
+        }
+}
+
 int mpol_set_shared_policy(struct shared_policy *info,
                         struct vm_area_struct *vma, struct mempolicy *npol)
 {