hugetlbfs: fix races and page leaks during migration

[linux-2.6-block.git] / fs / hugetlbfs / inode.c

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 32920a10100e23fc60f53cf36c882278ae972cee..a7fa037b876b7fa32afcc891345cd44f0315b4f9 100644 (file)
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -859,6 +859,18 @@ static int hugetlbfs_migrate_page(struct address_space *mapping,
        rc = migrate_huge_page_move_mapping(mapping, newpage, page);
        if (rc != MIGRATEPAGE_SUCCESS)
                return rc;
+
+       /*
+        * page_private is subpool pointer in hugetlb pages.  Transfer to
+        * new page.  PagePrivate is not associated with page_private for
+        * hugetlb pages and can not be set here as only page_huge_active
+        * pages can be migrated.
+        */
+       if (page_private(page)) {
+               set_page_private(newpage, page_private(page));
+               set_page_private(page, 0);
+       }
+
        if (mode != MIGRATE_SYNC_NO_COPY)
                migrate_page_copy(newpage, page);
        else