4 files changed, 37 insertions, 2 deletions

diff --git a/include/linux/migrate.h b/include/linux/migrate.h
index 5dba23a1c0d0..48148e0cdbd1 100644
--- a/include/linux/migrate.h
+++ b/include/linux/migrate.h
@@ -16,7 +16,9 @@ extern int fail_migrate_page(struct address_space *,
                         struct page *, struct page *);
 
 extern int migrate_prep(void);
-
+extern int migrate_vmas(struct mm_struct *mm,
+                const nodemask_t *from, const nodemask_t *to,
+                unsigned long flags);
 #else
 
 static inline int isolate_lru_page(struct page *p, struct list_head *list)
@@ -30,6 +32,13 @@ static inline int migrate_pages_to(struct list_head *pagelist,
 
 static inline int migrate_prep(void) { return -ENOSYS; }
 
+static inline int migrate_vmas(struct mm_struct *mm,
+                const nodemask_t *from, const nodemask_t *to,
+                unsigned long flags)
+{
+        return -ENOSYS;
+}
+
 /* Possible settings for the migrate_page() method in address_operations */
 #define migrate_page NULL
 #define fail_migrate_page NULL
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 71c5d2f667ed..a929ea197e48 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -206,6 +206,8 @@ struct vm_operations_struct {
         int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new);
         struct mempolicy *(*get_policy)(struct vm_area_struct *vma,
                                         unsigned long addr);
+        int (*migrate)(struct vm_area_struct *vma, const nodemask_t *from,
+                const nodemask_t *to, unsigned long flags);
 #endif
 };
 
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index ec4a1a950df9..73e0f23b7f51 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -632,6 +632,10 @@ int do_migrate_pages(struct mm_struct *mm,
 
         down_read(&mm->mmap_sem);
 
+        err = migrate_vmas(mm, from_nodes, to_nodes, flags);
+        if (err)
+                goto out;
+
 /*
  * Find a 'source' bit set in 'tmp' whose corresponding 'dest'
  * bit in 'to' is not also set in 'tmp'.  Clear the found 'source'
@@ -691,7 +695,7 @@ int do_migrate_pages(struct mm_struct *mm,
                 if (err < 0)
                         break;
         }
-
+out:
         up_read(&mm->mmap_sem);
         if (err < 0)
                 return err;
diff --git a/mm/migrate.c b/mm/migrate.c
index 1c2a71aa05cd..0576c0535988 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -976,3 +976,23 @@ out2:
 }
 #endif
 
+/*
+ * Call migration functions in the vma_ops that may prepare
+ * memory in a vm for migration. migration functions may perform
+ * the migration for vmas that do not have an underlying page struct.
+ */
+int migrate_vmas(struct mm_struct *mm, const nodemask_t *to,
+        const nodemask_t *from, unsigned long flags)
+{
+        struct vm_area_struct *vma;
+        int err = 0;
+
+        for(vma = mm->mmap; vma->vm_next && !err; vma = vma->vm_next) {
+                if (vma->vm_ops && vma->vm_ops->migrate) {
+                        err = vma->vm_ops->migrate(vma, to, from, flags);
+                        if (err)
+                                break;
+                }
+        }
+        return err;
+}