Re: [PATCH 1/2] mm/swap: rename subpage->page in folio_dup_swap/folio_put_swap

[Lorenzo Stoakes]

On Tue, Jun 23, 2026 at 12:57:21PM +0000, Dev Jain wrote:
> Folios have pages, not subpages. Rename 'subpage' parameters to 'page'.
>
> Acked-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>
> Signed-off-by: Dev Jain <dev.jain@xxxxxxx>

This subpatch of your series LGTM! ;) so:

Reviewed-by: Lorenzo Stoakes <ljs@xxxxxxxxxx>

Thanks, Lorenzo

> ---
>  mm/swap.h     |  4 ++--
>  mm/swapfile.c | 16 ++++++++--------
>  2 files changed, 10 insertions(+), 10 deletions(-)
>
> diff --git a/mm/swap.h b/mm/swap.h
> index 77d2d14eda421..44ab8e1e595b0 100644
> --- a/mm/swap.h
> +++ b/mm/swap.h
> @@ -230,8 +230,8 @@ extern int swap_retry_table_alloc(swp_entry_t entry, gfp_t gfp);
>   * folio_put_swap(): does the opposite thing of folio_dup_swap().
>   */
>  int folio_alloc_swap(struct folio *folio);
> -int folio_dup_swap(struct folio *folio, struct page *subpage);
> -void folio_put_swap(struct folio *folio, struct page *subpage);
> +int folio_dup_swap(struct folio *folio, struct page *page);
> +void folio_put_swap(struct folio *folio, struct page *page);
>
>  /* For internal use */
>  extern void __swap_cluster_free_entries(struct swap_info_struct *si,
> diff --git a/mm/swapfile.c b/mm/swapfile.c
> index 78b49b0658add..a602e5820513a 100644
> --- a/mm/swapfile.c
> +++ b/mm/swapfile.c
> @@ -1781,7 +1781,7 @@ int folio_alloc_swap(struct folio *folio)
>  /**
>   * folio_dup_swap() - Increase swap count of swap entries of a folio.
>   * @folio: folio with swap entries bounded.
> - * @subpage: if not NULL, only increase the swap count of this subpage.
> + * @page: if not NULL, only increase the swap count of this page.
>   *
>   * Typically called when the folio is unmapped and have its swap entry to
>   * take its place: Swap entries allocated to a folio has count == 0 and pinned
> @@ -1795,7 +1795,7 @@ int folio_alloc_swap(struct folio *folio)
>   * swap_put_entries_direct on its swap entry before this helper returns, or
>   * the swap count may underflow.
>   */
> -int folio_dup_swap(struct folio *folio, struct page *subpage)
> +int folio_dup_swap(struct folio *folio, struct page *page)
>  {
>  	swp_entry_t entry = folio->swap;
>  	unsigned long nr_pages = folio_nr_pages(folio);
> @@ -1803,8 +1803,8 @@ int folio_dup_swap(struct folio *folio, struct page *subpage)
>  	VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio);
>  	VM_WARN_ON_FOLIO(!folio_test_swapcache(folio), folio);
>
> -	if (subpage) {
> -		entry.val += folio_page_idx(folio, subpage);
> +	if (page) {
> +		entry.val += folio_page_idx(folio, page);
>  		nr_pages = 1;
>  	}
>
> @@ -1815,13 +1815,13 @@ int folio_dup_swap(struct folio *folio, struct page *subpage)
>  /**
>   * folio_put_swap() - Decrease swap count of swap entries of a folio.
>   * @folio: folio with swap entries bounded, must be in swap cache and locked.
> - * @subpage: if not NULL, only decrease the swap count of this subpage.
> + * @page: if not NULL, only decrease the swap count of this page.
>   *
>   * This won't free the swap slots even if swap count drops to zero, they are
>   * still pinned by the swap cache. User may call folio_free_swap to free them.
>   * Context: Caller must ensure the folio is locked and in the swap cache.
>   */
> -void folio_put_swap(struct folio *folio, struct page *subpage)
> +void folio_put_swap(struct folio *folio, struct page *page)
>  {
>  	swp_entry_t entry = folio->swap;
>  	unsigned long nr_pages = folio_nr_pages(folio);
> @@ -1830,8 +1830,8 @@ void folio_put_swap(struct folio *folio, struct page *subpage)
>  	VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio);
>  	VM_WARN_ON_FOLIO(!folio_test_swapcache(folio), folio);
>
> -	if (subpage) {
> -		entry.val += folio_page_idx(folio, subpage);
> +	if (page) {
> +		entry.val += folio_page_idx(folio, page);
>  		nr_pages = 1;
>  	}
>
> --
> 2.43.0
>