+ mm-swap-convert-__read_swap_cache_async-to-use-a-folio.patch added to mm-unstable branch

+ mm-swap-convert-__read_swap_cache_async-to-use-a-folio.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/swap: convert __read_swap_cache_async() to use a folio
has been added to the -mm mm-unstable branch.  Its filename is
     mm-swap-convert-__read_swap_cache_async-to-use-a-folio.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swap-convert-__read_swap_cache_async-to-use-a-folio.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm/swap: convert __read_swap_cache_async() to use a folio
Date: Fri, 2 Sep 2022 20:46:07 +0100

Remove a few hidden (and one visible) calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-12-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swap_state.c |   38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

--- a/mm/swap_state.c~mm-swap-convert-__read_swap_cache_async-to-use-a-folio
+++ a/mm/swap_state.c
@@ -411,7 +411,7 @@ struct page *__read_swap_cache_async(swp
 			bool *new_page_allocated)
 {
 	struct swap_info_struct *si;
-	struct page *page;
+	struct folio *folio;
 	void *shadow = NULL;
 
 	*new_page_allocated = false;
@@ -426,11 +426,11 @@ struct page *__read_swap_cache_async(swp
 		si = get_swap_device(entry);
 		if (!si)
 			return NULL;
-		page = find_get_page(swap_address_space(entry),
-				     swp_offset(entry));
+		folio = filemap_get_folio(swap_address_space(entry),
+						swp_offset(entry));
 		put_swap_device(si);
-		if (page)
-			return page;
+		if (folio)
+			return folio_file_page(folio, swp_offset(entry));
 
 		/*
 		 * Just skip read ahead for unused swap slot.
@@ -448,8 +448,8 @@ struct page *__read_swap_cache_async(swp
 		 * before marking swap_map SWAP_HAS_CACHE, when -EEXIST will
 		 * cause any racers to loop around until we add it to cache.
 		 */
-		page = alloc_page_vma(gfp_mask, vma, addr);
-		if (!page)
+		folio = vma_alloc_folio(gfp_mask, 0, vma, addr, false);
+		if (!folio)
 			return NULL;
 
 		/*
@@ -459,7 +459,7 @@ struct page *__read_swap_cache_async(swp
 		if (!err)
 			break;
 
-		put_page(page);
+		folio_put(folio);
 		if (err != -EEXIST)
 			return NULL;
 
@@ -477,30 +477,30 @@ struct page *__read_swap_cache_async(swp
 	 * The swap entry is ours to swap in. Prepare the new page.
 	 */
 
-	__SetPageLocked(page);
-	__SetPageSwapBacked(page);
+	__folio_set_locked(folio);
+	__folio_set_swapbacked(folio);
 
-	if (mem_cgroup_swapin_charge_page(page, NULL, gfp_mask, entry))
+	if (mem_cgroup_swapin_charge_page(&folio->page, NULL, gfp_mask, entry))
 		goto fail_unlock;
 
 	/* May fail (-ENOMEM) if XArray node allocation failed. */
-	if (add_to_swap_cache(page, entry, gfp_mask & GFP_RECLAIM_MASK, &shadow))
+	if (add_to_swap_cache(&folio->page, entry, gfp_mask & GFP_RECLAIM_MASK, &shadow))
 		goto fail_unlock;
 
 	mem_cgroup_swapin_uncharge_swap(entry);
 
 	if (shadow)
-		workingset_refault(page_folio(page), shadow);
+		workingset_refault(folio, shadow);
 
-	/* Caller will initiate read into locked page */
-	lru_cache_add(page);
+	/* Caller will initiate read into locked folio */
+	folio_add_lru(folio);
 	*new_page_allocated = true;
-	return page;
+	return &folio->page;
 
 fail_unlock:
-	put_swap_page(page, entry);
-	unlock_page(page);
-	put_page(page);
+	put_swap_page(&folio->page, entry);
+	folio_unlock(folio);
+	folio_put(folio);
 	return NULL;
 }
 
_

Patches currently in -mm which might be from willy@infradead.org are

tools-fix-compilation-after-gfp_typesh-split.patch
mm-fix-vm_bug_on-in-__delete_from_swap_cache.patch
vmscan-check-folio_test_private-not-folio_get_private.patch
support-highmem-pages-in-vmap_pages_range_noflush.patch
mm-add-vma-iterator.patch
mmap-use-the-vma-iterator-in-count_vma_pages_range.patch
proc-remove-vma-rbtree-use-from-nommu.patch
arm64-remove-mmap-linked-list-from-vdso.patch
parisc-remove-mmap-linked-list-from-cache-handling.patch
powerpc-remove-mmap-linked-list-walks.patch
s390-remove-vma-linked-list-walks.patch
x86-remove-vma-linked-list-walks.patch
xtensa-remove-vma-linked-list-walks.patch
cxl-remove-vma-linked-list-walk.patch
optee-remove-vma-linked-list-walk.patch
um-remove-vma-linked-list-walk.patch
coredump-remove-vma-linked-list-walk.patch
exec-use-vma-iterator-instead-of-linked-list.patch
fs-proc-task_mmu-stop-using-linked-list-and-highest_vm_end.patch
acct-use-vma-iterator-instead-of-linked-list.patch
perf-use-vma-iterator.patch
sched-use-maple-tree-iterator-to-walk-vmas.patch
fork-use-vma-iterator.patch
mm-khugepaged-stop-using-vma-linked-list.patch
mm-ksm-use-vma-iterators-instead-of-vma-linked-list.patch
mm-mlock-use-vma-iterator-and-maple-state-instead-of-vma-linked-list.patch
mm-pagewalk-use-vma_find-instead-of-vma-linked-list.patch
i915-use-the-vma-iterator.patch
nommu-remove-uses-of-vma-linked-list.patch
mm-vmscan-fix-a-lot-of-comments.patch
mm-add-the-first-tail-page-to-struct-folio.patch
mm-reimplement-folio_order-and-folio_nr_pages.patch
mm-add-split_folio.patch
mm-add-folio_add_lru_vma.patch
shmem-convert-shmem_writepage-to-use-a-folio-throughout.patch
shmem-convert-shmem_delete_from_page_cache-to-take-a-folio.patch
shmem-convert-shmem_replace_page-to-use-folios-throughout.patch
mm-swapfile-remove-page_swapcount.patch
mm-swapfile-convert-try_to_free_swap-to-folio_free_swap.patch
mm-swap-convert-__read_swap_cache_async-to-use-a-folio.patch
mm-swap-convert-add_to_swap_cache-to-take-a-folio.patch
mm-swap-convert-put_swap_page-to-put_swap_folio.patch
mm-convert-do_swap_page-to-use-a-folio.patch
mm-convert-do_swap_pages-swapcache-variable-to-a-folio.patch
memcg-convert-mem_cgroup_swapin_charge_page-to-mem_cgroup_swapin_charge_folio.patch
shmem-convert-shmem_mfill_atomic_pte-to-use-a-folio.patch
shmem-convert-shmem_replace_page-to-shmem_replace_folio.patch
swap-add-swap_cache_get_folio.patch
shmem-eliminate-struct-page-from-shmem_swapin_folio.patch
shmem-convert-shmem_getpage_gfp-to-shmem_get_folio_gfp.patch
shmem-convert-shmem_fault-to-use-shmem_get_folio_gfp.patch
shmem-convert-shmem_read_mapping_page_gfp-to-use-shmem_get_folio_gfp.patch
shmem-add-shmem_get_folio.patch
shmem-convert-shmem_get_partial_folio-to-use-shmem_get_folio.patch
shmem-convert-shmem_write_begin-to-use-shmem_get_folio.patch
shmem-convert-shmem_file_read_iter-to-use-shmem_get_folio.patch
shmem-convert-shmem_fallocate-to-use-a-folio.patch
shmem-convert-shmem_symlink-to-use-a-folio.patch
shmem-convert-shmem_get_link-to-use-a-folio.patch
khugepaged-call-shmem_get_folio.patch
userfaultfd-convert-mcontinue_atomic_pte-to-use-a-folio.patch
shmem-remove-shmem_getpage.patch
swapfile-convert-try_to_unuse-to-use-a-folio.patch
swapfile-convert-__try_to_reclaim_swap-to-use-a-folio.patch
swapfile-convert-unuse_pte_range-to-use-a-folio.patch
mm-convert-do_swap_page-to-use-swap_cache_get_folio.patch
mm-remove-lookup_swap_cache.patch
swap_state-convert-free_swap_cache-to-use-a-folio.patch
swap-convert-swap_writepage-to-use-a-folio.patch
mm-convert-do_wp_page-to-use-a-folio.patch
huge_memory-convert-do_huge_pmd_wp_page-to-use-a-folio.patch
madvise-convert-madvise_free_pte_range-to-use-a-folio.patch
uprobes-use-folios-more-widely-in-__replace_page.patch
ksm-use-a-folio-in-replace_page.patch
mm-convert-do_swap_page-to-use-folio_free_swap.patch
memcg-convert-mem_cgroup_swap_full-to-take-a-folio.patch
mm-remove-try_to_free_swap.patch
rmap-convert-page_move_anon_rmap-to-use-a-folio.patch
migrate-convert-__unmap_and_move-to-use-folios.patch
migrate-convert-unmap_and_move_huge_page-to-use-folios.patch
huge_memory-convert-split_huge_page_to_list-to-use-a-folio.patch
huge_memory-convert-unmap_page-to-unmap_folio.patch
mm-convert-page_get_anon_vma-to-folio_get_anon_vma.patch
rmap-remove-page_unlock_anon_vma_read.patch
uprobes-use-new_folio-in-__replace_page.patch
mm-convert-lock_page_or_retry-to-folio_lock_or_retry.patch