Commit 3720dd6d authored by Vishal Moola (Oracle)'s avatar Vishal Moola (Oracle) Committed by Andrew Morton
Browse files

filemap: convert replace_page_cache_page() to replace_page_cache_folio() 

Patch series "Removing the lru_cache_add() wrapper".

This patchset replaces all calls of lru_cache_add() with the folio
equivalent: folio_add_lru().  This is allows us to get rid of the wrapper
The series passes xfstests and the userfaultfd selftests.


This patch (of 5):

Eliminates 7 calls to compound_head().

Link: https://lkml.kernel.org/r/20221101175326.13265-1-vishal.moola@gmail.com
Link: https://lkml.kernel.org/r/20221101175326.13265-2-vishal.moola@gmail.com


Signed-off-by: default avatarVishal Moola (Oracle) <vishal.moola@gmail.com>
Reviewed-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent c5a303a5

fs/fuse/dev.c

+1 −1
Original line number Diff line number Diff line
@@ -837,7 +837,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) 
	if (WARN_ON(PageMlocked(oldpage)))

		goto out_fallback_unlock;



	replace_page_cache_page(oldpage, newpage);

	replace_page_cache_folio(page_folio(oldpage), page_folio(newpage));



	get_page(newpage);

include/linux/pagemap.h

+1 −1
Original line number Diff line number Diff line
@@ -1102,7 +1102,7 @@ int filemap_add_folio(struct address_space *mapping, struct folio *folio, 
		pgoff_t index, gfp_t gfp);

void filemap_remove_folio(struct folio *folio);

void __filemap_remove_folio(struct folio *folio, void *shadow);

void replace_page_cache_page(struct page *old, struct page *new);

void replace_page_cache_folio(struct folio *old, struct folio *new);

void delete_from_page_cache_batch(struct address_space *mapping,

				  struct folio_batch *fbatch);

bool filemap_release_folio(struct folio *folio, gfp_t gfp);

mm/filemap.c

+25 −27
Original line number Diff line number Diff line
@@ -788,56 +788,54 @@ int file_write_and_wait_range(struct file *file, loff_t lstart, loff_t lend) 
EXPORT_SYMBOL(file_write_and_wait_range);



/**

 * replace_page_cache_page - replace a pagecache page with a new one

 * @old:	page to be replaced

 * @new:	page to replace with

 *

 * This function replaces a page in the pagecache with a new one.  On

 * success it acquires the pagecache reference for the new page and

 * drops it for the old page.  Both the old and new pages must be

 * locked.  This function does not add the new page to the LRU, the

 * replace_page_cache_folio - replace a pagecache folio with a new one

 * @old:	folio to be replaced

 * @new:	folio to replace with

 *

 * This function replaces a folio in the pagecache with a new one.  On

 * success it acquires the pagecache reference for the new folio and

 * drops it for the old folio.  Both the old and new folios must be

 * locked.  This function does not add the new folio to the LRU, the

 * caller must do that.

 *

 * The remove + add is atomic.  This function cannot fail.

 */

void replace_page_cache_page(struct page *old, struct page *new)

void replace_page_cache_folio(struct folio *old, struct folio *new)

{

	struct folio *fold = page_folio(old);

	struct folio *fnew = page_folio(new);

	struct address_space *mapping = old->mapping;

	void (*free_folio)(struct folio *) = mapping->a_ops->free_folio;

	pgoff_t offset = old->index;

	XA_STATE(xas, &mapping->i_pages, offset);



	VM_BUG_ON_PAGE(!PageLocked(old), old);

	VM_BUG_ON_PAGE(!PageLocked(new), new);

	VM_BUG_ON_PAGE(new->mapping, new);

	VM_BUG_ON_FOLIO(!folio_test_locked(old), old);

	VM_BUG_ON_FOLIO(!folio_test_locked(new), new);

	VM_BUG_ON_FOLIO(new->mapping, new);



	get_page(new);

	folio_get(new);

	new->mapping = mapping;

	new->index = offset;



	mem_cgroup_migrate(fold, fnew);

	mem_cgroup_migrate(old, new);



	xas_lock_irq(&xas);

	xas_store(&xas, new);



	old->mapping = NULL;

	/* hugetlb pages do not participate in page cache accounting. */

	if (!PageHuge(old))

		__dec_lruvec_page_state(old, NR_FILE_PAGES);

	if (!PageHuge(new))

		__inc_lruvec_page_state(new, NR_FILE_PAGES);

	if (PageSwapBacked(old))

		__dec_lruvec_page_state(old, NR_SHMEM);

	if (PageSwapBacked(new))

		__inc_lruvec_page_state(new, NR_SHMEM);

	if (!folio_test_hugetlb(old))

		__lruvec_stat_sub_folio(old, NR_FILE_PAGES);

	if (!folio_test_hugetlb(new))

		__lruvec_stat_add_folio(new, NR_FILE_PAGES);

	if (folio_test_swapbacked(old))

		__lruvec_stat_sub_folio(old, NR_SHMEM);

	if (folio_test_swapbacked(new))

		__lruvec_stat_add_folio(new, NR_SHMEM);

	xas_unlock_irq(&xas);

	if (free_folio)

		free_folio(fold);

	folio_put(fold);

		free_folio(old);

	folio_put(old);

}

EXPORT_SYMBOL_GPL(replace_page_cache_page);

EXPORT_SYMBOL_GPL(replace_page_cache_folio);



noinline int __filemap_add_folio(struct address_space *mapping,

		struct folio *folio, pgoff_t index, gfp_t gfp, void **shadowp)