From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Add a helper to allow filesystems to attempt to free the 'dropbehind' folio. Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/all/5588a06f6d5a2cf6746828e2d36e7ada668b1739.1745381692.git.trond.myklebust@xxxxxxxxxxxxxxx/ Reviewed-by: Mike Snitzer <snitzer@xxxxxxxxxx> --- include/linux/pagemap.h | 1 + mm/filemap.c | 11 +++++++++++ 2 files changed, 12 insertions(+) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 12a12dae727d..201b7c6f6441 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 751838ef05e5..e35dd0f90850 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1666,6 +1666,17 @@ void folio_end_writeback(struct folio *folio) } EXPORT_SYMBOL(folio_end_writeback); +/* + * Helper for filesystems that want to implement dropbehind, and that + * need to keep the folio around after folio_end_writeback, e.g. due to + * the need to first commit NFS stable writes. + */ +void folio_end_dropbehind(struct folio *folio) +{ + filemap_end_dropbehind_write(folio); +} +EXPORT_SYMBOL(folio_end_dropbehind); + /** * __folio_lock - Get a lock on the folio, assuming we need to sleep to get it. * @folio: The folio to lock -- 2.50.1
