[PATCH v3 2/8] iomap: Remove large folio handling in iomap_invalidate_folio()

Matthew Wilcox (Oracle)
2023-06-12T20:39:37Z

We do not need to release the iomap_page in iomap_invalidate_folio()
to allow the folio to be split. The splitting code will call
->release_folio() if there is still per-fs private data attached to
the folio. At that point, we will check if the folio is still dirty
and decline to release the iomap_page. It is possible to trigger the
warning in perfectly legitimate circumstances (eg if a disk read fails,
we do a partial write to the folio, then we truncate the folio), which
will cause those writes to be lost.

Fixes: 60d8231089f0 ("iomap: Support large folios in invalidatepage")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
fs/iomap/buffered-io.c | 5 -----
1 file changed, 5 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 063133ec77f4..08ee293c4117 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -508,11 +508,6 @@ void iomap_invalidate_folio(struct folio *folio, size_t offset, size_t len)
WARN_ON_ONCE(folio_test_writeback(folio));
folio_cancel_dirty(folio);
iomap_page_release(folio);
- } else if (folio_test_large(folio)) {
- /* Must release the iop so the page can be split */
- WARN_ON_ONCE(!folio_test_uptodate(folio) &&
- folio_test_dirty(folio));
- iomap_page_release(folio);
}
}
EXPORT_SYMBOL_GPL(iomap_invalidate_folio);
--
2.39.2