Commit 24bbd533 authored by Trond Myklebust's avatar Trond Myklebust Committed by Anna Schumaker
Browse files

filemap: Add a helper for filesystems implementing dropbehind 



Add a helper to allow filesystems to attempt to free the 'dropbehind'
folio.

Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
Link: https://lore.kernel.org/all/5588a06f6d5a2cf6746828e2d36e7ada668b1739.1745381692.git.trond.myklebust@hammerspace.com/


Reviewed-by: default avatarMike Snitzer <snitzer@kernel.org>
Signed-off-by: default avatarAnna Schumaker <anna.schumaker@oracle.com>
parent cc6ac66f

include/linux/pagemap.h

+1 −0
Original line number Diff line number Diff line
@@ -1221,6 +1221,7 @@ void folio_wait_writeback(struct folio *folio); 
int folio_wait_writeback_killable(struct folio *folio);

void end_page_writeback(struct page *page);

void folio_end_writeback(struct folio *folio);

void folio_end_dropbehind(struct folio *folio);

void folio_wait_stable(struct folio *folio);

void __folio_mark_dirty(struct folio *folio, struct address_space *, int warn);

void folio_account_cleaned(struct folio *folio, struct bdi_writeback *wb);

mm/filemap.c

+3 −2
Original line number Diff line number Diff line
@@ -1608,7 +1608,7 @@ static void filemap_end_dropbehind(struct folio *folio) 
 * completes. Do that now. If we fail, it's likely because of a big folio -

 * just reset dropbehind for that case and latter completions should invalidate.

 */

static void filemap_end_dropbehind_write(struct folio *folio)

void folio_end_dropbehind(struct folio *folio)

{

	if (!folio_test_dropbehind(folio))

		return;
@@ -1625,6 +1625,7 @@ static void filemap_end_dropbehind_write(struct folio *folio) 
		folio_unlock(folio);

	}

}

EXPORT_SYMBOL_GPL(folio_end_dropbehind);



/**

 * folio_end_writeback - End writeback against a folio.
@@ -1660,7 +1661,7 @@ void folio_end_writeback(struct folio *folio) 
	if (__folio_end_writeback(folio))

		folio_wake_bit(folio, PG_writeback);



	filemap_end_dropbehind_write(folio);

	folio_end_dropbehind(folio);

	acct_reclaim_writeback(folio);

	folio_put(folio);

}