Commit 452e9e69 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle)
Browse files

filemap: Add filemap_remove_folio and __filemap_remove_folio 



Reimplement __delete_from_page_cache() as a wrapper around
__filemap_remove_folio() and delete_from_page_cache() as a wrapper
around filemap_remove_folio().  Remove the EXPORT_SYMBOL as
delete_from_page_cache() was not used by any in-tree modules.
Convert page_cache_free_page() into filemap_free_folio().

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarWilliam Kucharski <william.kucharski@oracle.com>
parent a0580c6f

include/linux/pagemap.h

+7 −2
Original line number Diff line number Diff line
@@ -930,8 +930,13 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping, 
		pgoff_t index, gfp_t gfp);

int filemap_add_folio(struct address_space *mapping, struct folio *folio,

		pgoff_t index, gfp_t gfp);

extern void delete_from_page_cache(struct page *page);

extern void __delete_from_page_cache(struct page *page, void *shadow);

void filemap_remove_folio(struct folio *folio);

void delete_from_page_cache(struct page *page);

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

static inline void __delete_from_page_cache(struct page *page, void *shadow)

{

	__filemap_remove_folio(page_folio(page), shadow);

}

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

void delete_from_page_cache_batch(struct address_space *mapping,

				  struct pagevec *pvec);

mm/filemap.c

+20 −23
Original line number Diff line number Diff line
@@ -220,58 +220,55 @@ static void filemap_unaccount_folio(struct address_space *mapping, 
 * sure the page is locked and that nobody else uses it - or that usage

 * is safe.  The caller must hold the i_pages lock.

 */

void __delete_from_page_cache(struct page *page, void *shadow)

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

{

	struct folio *folio = page_folio(page);

	struct address_space *mapping = page->mapping;

	struct address_space *mapping = folio->mapping;



	trace_mm_filemap_delete_from_page_cache(folio);



	filemap_unaccount_folio(mapping, folio);

	page_cache_delete(mapping, folio, shadow);

}



static void page_cache_free_page(struct address_space *mapping,

				struct page *page)

static void filemap_free_folio(struct address_space *mapping,

				struct folio *folio)

{

	void (*freepage)(struct page *);



	freepage = mapping->a_ops->freepage;

	if (freepage)

		freepage(page);

		freepage(&folio->page);



	if (PageTransHuge(page) && !PageHuge(page)) {

		page_ref_sub(page, thp_nr_pages(page));

		VM_BUG_ON_PAGE(page_count(page) <= 0, page);

	if (folio_test_large(folio) && !folio_test_hugetlb(folio)) {

		folio_ref_sub(folio, folio_nr_pages(folio));

		VM_BUG_ON_FOLIO(folio_ref_count(folio) <= 0, folio);

	} else {

		put_page(page);

		folio_put(folio);

	}

}



/**

 * delete_from_page_cache - delete page from page cache

 * @page: the page which the kernel is trying to remove from page cache

 * filemap_remove_folio - Remove folio from page cache.

 * @folio: The folio.

 *

 * This must be called only on pages that have been verified to be in the page

 * cache and locked.  It will never put the page into the free list, the caller

 * has a reference on the page.

 * This must be called only on folios that are locked and have been

 * verified to be in the page cache.  It will never put the folio into

 * the free list because the caller has a reference on the page.

 */

void delete_from_page_cache(struct page *page)

void filemap_remove_folio(struct folio *folio)

{

	struct address_space *mapping = page_mapping(page);

	struct address_space *mapping = folio->mapping;



	BUG_ON(!PageLocked(page));

	BUG_ON(!folio_test_locked(folio));

	spin_lock(&mapping->host->i_lock);

	xa_lock_irq(&mapping->i_pages);

	__delete_from_page_cache(page, NULL);

	__filemap_remove_folio(folio, NULL);

	xa_unlock_irq(&mapping->i_pages);

	if (mapping_shrinkable(mapping))

		inode_add_lru(mapping->host);

	spin_unlock(&mapping->host->i_lock);



	page_cache_free_page(mapping, page);

	filemap_free_folio(mapping, folio);

}

EXPORT_SYMBOL(delete_from_page_cache);



/*

 * page_cache_delete_batch - delete several pages from page cache
@@ -358,7 +355,7 @@ void delete_from_page_cache_batch(struct address_space *mapping, 
	spin_unlock(&mapping->host->i_lock);



	for (i = 0; i < pagevec_count(pvec); i++)

		page_cache_free_page(mapping, pvec->pages[i]);

		filemap_free_folio(mapping, page_folio(pvec->pages[i]));

}



int filemap_check_errors(struct address_space *mapping)

mm/folio-compat.c

+5 −0
Original line number Diff line number Diff line
@@ -140,3 +140,8 @@ struct page *grab_cache_page_write_begin(struct address_space *mapping, 
			mapping_gfp_mask(mapping));

}

EXPORT_SYMBOL(grab_cache_page_write_begin);



void delete_from_page_cache(struct page *page)

{

	return filemap_remove_folio(page_folio(page));

}