From: Trond Myklebust Date: Sat, 6 Sep 2025 16:48:14 +0000 (-0400) Subject: filemap: Add a helper for filesystems implementing dropbehind X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=24bbd533f596a4544e17579e9f622918680e7bff;p=thirdparty%2Fkernel%2Fstable.git filemap: Add a helper for filesystems implementing dropbehind Add a helper to allow filesystems to attempt to free the 'dropbehind' folio. Signed-off-by: Trond Myklebust Link: https://lore.kernel.org/all/5588a06f6d5a2cf6746828e2d36e7ada668b1739.1745381692.git.trond.myklebust@hammerspace.com/ Reviewed-by: Mike Snitzer Signed-off-by: Anna Schumaker --- diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 12a12dae727d0..201b7c6f64415 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -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); diff --git a/mm/filemap.c b/mm/filemap.c index 751838ef05e51..66cec689bec4f 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -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); }