Commit 6e03492e authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

mm: return a folio from read_swap_cache_async() 

The only two callers simply call put_page() on the page returned, so
they're happier calling folio_put().  Saves two calls to compound_head().

Link: https://lkml.kernel.org/r/20231213215842.671461-13-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 69fe7d67

mm/madvise.c

+11 −11
Original line number Diff line number Diff line
@@ -180,7 +180,7 @@ static int swapin_walk_pmd_entry(pmd_t *pmd, unsigned long start, 
	for (addr = start; addr < end; addr += PAGE_SIZE) {

		pte_t pte;

		swp_entry_t entry;

		struct page *page;

		struct folio *folio;



		if (!ptep++) {

			ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
@@ -198,10 +198,10 @@ static int swapin_walk_pmd_entry(pmd_t *pmd, unsigned long start, 
		pte_unmap_unlock(ptep, ptl);

		ptep = NULL;



		page = read_swap_cache_async(entry, GFP_HIGHUSER_MOVABLE,

		folio = read_swap_cache_async(entry, GFP_HIGHUSER_MOVABLE,

					     vma, addr, &splug);

		if (page)

			put_page(page);

		if (folio)

			folio_put(folio);

	}



	if (ptep)
@@ -223,17 +223,17 @@ static void shmem_swapin_range(struct vm_area_struct *vma, 
{

	XA_STATE(xas, &mapping->i_pages, linear_page_index(vma, start));

	pgoff_t end_index = linear_page_index(vma, end) - 1;

	struct page *page;

	struct folio *folio;

	struct swap_iocb *splug = NULL;



	rcu_read_lock();

	xas_for_each(&xas, page, end_index) {

	xas_for_each(&xas, folio, end_index) {

		unsigned long addr;

		swp_entry_t entry;



		if (!xa_is_value(page))

		if (!xa_is_value(folio))

			continue;

		entry = radix_to_swp_entry(page);

		entry = radix_to_swp_entry(folio);

		/* There might be swapin error entries in shmem mapping. */

		if (non_swap_entry(entry))

			continue;
@@ -243,10 +243,10 @@ static void shmem_swapin_range(struct vm_area_struct *vma, 
		xas_pause(&xas);

		rcu_read_unlock();



		page = read_swap_cache_async(entry, mapping_gfp_mask(mapping),

		folio = read_swap_cache_async(entry, mapping_gfp_mask(mapping),

					     vma, addr, &splug);

		if (page)

			put_page(page);

		if (folio)

			folio_put(folio);



		rcu_read_lock();

	}

mm/swap.h

+3 −4
Original line number Diff line number Diff line
@@ -46,9 +46,8 @@ struct folio *swap_cache_get_folio(swp_entry_t entry, 
struct folio *filemap_get_incore_folio(struct address_space *mapping,

		pgoff_t index);



struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,

				   struct vm_area_struct *vma,

				   unsigned long addr,

struct folio *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,

		struct vm_area_struct *vma, unsigned long addr,

		struct swap_iocb **plug);

struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_flags,

		struct mempolicy *mpol, pgoff_t ilx, bool *new_page_allocated,

mm/swap_state.c

+4 −4
Original line number Diff line number Diff line
@@ -533,9 +533,9 @@ struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 
 * __read_swap_cache_async() call them and swap_read_folio() holds the

 * swap cache folio lock.

 */

struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,

				   struct vm_area_struct *vma,

				   unsigned long addr, struct swap_iocb **plug)

struct folio *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,

		struct vm_area_struct *vma, unsigned long addr,

		struct swap_iocb **plug)

{

	bool page_allocated;

	struct mempolicy *mpol;
@@ -549,7 +549,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, 


	if (page_allocated)

		swap_read_folio(folio, false, plug);

	return folio_file_page(folio, swp_offset(entry));

	return folio;

}



static unsigned int __swapin_nr_pages(unsigned long prev_offset,