On Fri, Sep 15, 2023 at 08:38:31PM +0200, Pankaj Raghav wrote:
> From: Luis Chamberlain <mcgrof@xxxxxxxxxx>
>
> Call xas_set_order() in replace_page_cache_folio() for non hugetlb
> pages.
This function definitely should work without this patch. What goes wrong?
> Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>
> ---
> mm/filemap.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 4dee24b5b61c..33de71bfa953 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -815,12 +815,14 @@ EXPORT_SYMBOL(file_write_and_wait_range);
> void replace_page_cache_folio(struct folio *old, struct folio *new)
> {
> struct address_space *mapping = old->mapping;
> + unsigned int min_order = mapping_min_folio_order(mapping);
> void (*free_folio)(struct folio *) = mapping->a_ops->free_folio;
> pgoff_t offset = old->index;
> XA_STATE(xas, &mapping->i_pages, offset);
>
> VM_BUG_ON_FOLIO(!folio_test_locked(old), old);
> VM_BUG_ON_FOLIO(!folio_test_locked(new), new);
> + VM_BUG_ON_FOLIO(folio_order(new) != folio_order(old), new);
> VM_BUG_ON_FOLIO(new->mapping, new);
>
> folio_get(new);
> @@ -829,6 +831,11 @@ void replace_page_cache_folio(struct folio *old, struct folio *new)
>
> mem_cgroup_migrate(old, new);
>
> + if (!folio_test_hugetlb(new)) {
> + VM_BUG_ON_FOLIO(folio_order(new) < min_order, new);
> + xas_set_order(&xas, offset, folio_order(new));
> + }
> +
> xas_lock_irq(&xas);
> xas_store(&xas, new);
>
> --
> 2.40.1
>
