Commit b5612c36 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Andrew Morton
Browse files

mm: return void from folio_start_writeback() and related functions 

Nobody now checks the return value from any of these functions, so
add an assertion at the beginning of the function and return void.

Link: https://lkml.kernel.org/r/20231108204605.745109-5-willy@infradead.org


Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent a9540e35

include/linux/page-flags.h

+2 −2
Original line number Diff line number Diff line
@@ -772,8 +772,8 @@ static __always_inline void SetPageUptodate(struct page *page) 


CLEARPAGEFLAG(Uptodate, uptodate, PF_NO_TAIL)



bool __folio_start_writeback(struct folio *folio, bool keep_write);

bool set_page_writeback(struct page *page);

void __folio_start_writeback(struct folio *folio, bool keep_write);

void set_page_writeback(struct page *page);



#define folio_start_writeback(folio)			\

	__folio_start_writeback(folio, false)

mm/folio-compat.c

+2 −2
Original line number Diff line number Diff line
@@ -46,9 +46,9 @@ void mark_page_accessed(struct page *page) 
}

EXPORT_SYMBOL(mark_page_accessed);



bool set_page_writeback(struct page *page)

void set_page_writeback(struct page *page)

{

	return folio_start_writeback(page_folio(page));

	folio_start_writeback(page_folio(page));

}

EXPORT_SYMBOL(set_page_writeback);

mm/page-writeback.c

+25 −29
Original line number Diff line number Diff line
@@ -2982,28 +2982,27 @@ bool __folio_end_writeback(struct folio *folio) 
	return ret;

}



bool __folio_start_writeback(struct folio *folio, bool keep_write)

void __folio_start_writeback(struct folio *folio, bool keep_write)

{

	long nr = folio_nr_pages(folio);

	struct address_space *mapping = folio_mapping(folio);

	bool ret;

	int access_ret;



	VM_BUG_ON_FOLIO(folio_test_writeback(folio), folio);



	folio_memcg_lock(folio);

	if (mapping && mapping_use_writeback_tags(mapping)) {

		XA_STATE(xas, &mapping->i_pages, folio_index(folio));

		struct inode *inode = mapping->host;

		struct backing_dev_info *bdi = inode_to_bdi(inode);

		unsigned long flags;

		bool on_wblist;



		xas_lock_irqsave(&xas, flags);

		xas_load(&xas);

		ret = folio_test_set_writeback(folio);

		if (!ret) {

			bool on_wblist;

		folio_test_set_writeback(folio);



			on_wblist = mapping_tagged(mapping,

						   PAGECACHE_TAG_WRITEBACK);

		on_wblist = mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK);



		xas_set_mark(&xas, PAGECACHE_TAG_WRITEBACK);

		if (bdi->capabilities & BDI_CAP_WRITEBACK_ACCT) {
@@ -3015,34 +3014,31 @@ bool __folio_start_writeback(struct folio *folio, bool keep_write) 
		}



		/*

			 * We can come through here when swapping

			 * anonymous folios, so we don't necessarily

			 * have an inode to track for sync.

		 * We can come through here when swapping anonymous

		 * folios, so we don't necessarily have an inode to

		 * track for sync.

		 */

		if (mapping->host && !on_wblist)

			sb_mark_inode_writeback(mapping->host);

		}

		if (!folio_test_dirty(folio))

			xas_clear_mark(&xas, PAGECACHE_TAG_DIRTY);

		if (!keep_write)

			xas_clear_mark(&xas, PAGECACHE_TAG_TOWRITE);

		xas_unlock_irqrestore(&xas, flags);

	} else {

		ret = folio_test_set_writeback(folio);

		folio_test_set_writeback(folio);

	}

	if (!ret) {



	lruvec_stat_mod_folio(folio, NR_WRITEBACK, nr);

	zone_stat_mod_folio(folio, NR_ZONE_WRITE_PENDING, nr);

	}

	folio_memcg_unlock(folio);



	access_ret = arch_make_folio_accessible(folio);

	/*

	 * If writeback has been triggered on a page that cannot be made

	 * accessible, it is too late to recover here.

	 */

	VM_BUG_ON_FOLIO(access_ret != 0, folio);



	return ret;

}

EXPORT_SYMBOL(__folio_start_writeback);