The patch titled Subject: mm: return a folio from read_swap_cache_async() has been added to the -mm mm-unstable branch. Its filename is mm-return-a-folio-from-read_swap_cache_async.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-return-a-folio-from-read_swap_cache_async.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm: return a folio from read_swap_cache_async() Date: Wed, 13 Dec 2023 21:58:41 +0000 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@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/madvise.c | 22 +++++++++++----------- mm/swap.h | 7 +++---- mm/swap_state.c | 8 ++++---- 3 files changed, 18 insertions(+), 19 deletions(-) --- a/mm/madvise.c~mm-return-a-folio-from-read_swap_cache_async +++ a/mm/madvise.c @@ -180,7 +180,7 @@ static int swapin_walk_pmd_entry(pmd_t * 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 * 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 { 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 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(); } --- a/mm/swap.h~mm-return-a-folio-from-read_swap_cache_async +++ a/mm/swap.h @@ -46,10 +46,9 @@ struct folio *swap_cache_get_folio(swp_e 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 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); struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_flags, struct mempolicy *mpol, pgoff_t ilx, bool *new_page_allocated, bool skip_if_exists); --- a/mm/swap_state.c~mm-return-a-folio-from-read_swap_cache_async +++ a/mm/swap_state.c @@ -533,9 +533,9 @@ fail_put_swap: * __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_e 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, _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are buffer-return-bool-from-grow_dev_folio.patch buffer-calculate-block-number-inside-folio_init_buffers.patch buffer-fix-grow_buffers-for-block-size-page_size.patch buffer-cast-block-to-loff_t-before-shifting-it.patch buffer-fix-various-functions-for-block-size-page_size.patch buffer-handle-large-folios-in-__block_write_begin_int.patch buffer-fix-more-functions-for-block-size-page_size.patch mm-convert-ksm_might_need_to_copy-to-work-on-folios.patch mm-remove-pageanonexclusive-assertions-in-unuse_pte.patch mm-convert-unuse_pte-to-use-a-folio-throughout.patch mm-remove-some-calls-to-page_add_new_anon_rmap.patch mm-remove-stale-example-from-comment.patch mm-remove-references-to-page_add_new_anon_rmap-in-comments.patch mm-convert-migrate_vma_insert_page-to-use-a-folio.patch mm-convert-collapse_huge_page-to-use-a-folio.patch mm-remove-page_add_new_anon_rmap-and-lru_cache_add_inactive_or_unevictable.patch mm-return-the-folio-from-__read_swap_cache_async.patch mm-pass-a-folio-to-__swap_writepage.patch mm-pass-a-folio-to-swap_writepage_fs.patch mm-pass-a-folio-to-swap_writepage_bdev_sync.patch mm-pass-a-folio-to-swap_writepage_bdev_async.patch mm-pass-a-folio-to-swap_readpage_fs.patch mm-pass-a-folio-to-swap_readpage_bdev_sync.patch mm-pass-a-folio-to-swap_readpage_bdev_async.patch mm-convert-swap_page_sector-to-swap_folio_sector.patch mm-convert-swap_readpage-to-swap_read_folio.patch mm-remove-page_swap_info.patch mm-return-a-folio-from-read_swap_cache_async.patch mm-convert-swap_cluster_readahead-and-swap_vma_readahead-to-return-a-folio.patch