Re: [PATCH 1/6] mm: ksm: use more folio api in ksm_might_need_to_copy()

[Matthew Wilcox]

On Tue, Nov 07, 2023 at 09:52:11PM +0800, Kefeng Wang wrote:
>  struct page *ksm_might_need_to_copy(struct page *page,
> -			struct vm_area_struct *vma, unsigned long address)
> +			struct vm_area_struct *vma, unsigned long addr)
>  {
>  	struct folio *folio = page_folio(page);
>  	struct anon_vma *anon_vma = folio_anon_vma(folio);
> -	struct page *new_page;
> +	struct folio *new_folio;
>  
> -	if (PageKsm(page)) {
> -		if (page_stable_node(page) &&
> +	if (folio_test_ksm(folio)) {
> +		if (folio_stable_node(folio) &&
>  		    !(ksm_run & KSM_RUN_UNMERGE))
>  			return page;	/* no need to copy it */
>  	} else if (!anon_vma) {
>  		return page;		/* no need to copy it */
> -	} else if (page->index == linear_page_index(vma, address) &&
> +	} else if (page->index == linear_page_index(vma, addr) &&

Hmm.  page->index is going away.  What should we do here instead?

The rest of this looks good.