[PATCH 2/6] hugetlbfs: fix cannot migrate the fallocated HugeTLB page

[Muchun Song]

Because we only can isolate a active page via isolate_huge_page()
and hugetlbfs_fallocate() forget to mark it as active, we cannot
isolate and migrate those pages.

Fixes: 70c3547e36f5 (hugetlbfs: add hugetlbfs_fallocate())
Signed-off-by: Muchun Song <songmuc...@bytedance.com>
---
 fs/hugetlbfs/inode.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index b5c109703daa..2aceb085d202 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -737,10 +737,11 @@ static long hugetlbfs_fallocate(struct file *file, int 
mode, loff_t offset,
 
                /*
                 * unlock_page because locked by add_to_page_cache()
-                * page_put due to reference from alloc_huge_page()
+                * put_page() (which is in the putback_active_hugepage())
+                * due to reference from alloc_huge_page()
                 */
                unlock_page(page);
-               put_page(page);
+               putback_active_hugepage(page);
        }
 
        if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > inode->i_size)
-- 
2.11.0