[PATCH v2 2/6] iomap: support invalidating partial folios

Zhang Yi
2024-08-12T12:16:20Z

From: Zhang Yi <yi.zhang@huawei.com>

Current iomap_invalidate_folio() could only invalidate an entire folio,
if we truncate a partial folio on a filesystem with blocksize < folio
size, it will left over the dirty bits of truncated/punched blocks, and
the write back process will try to map the invalid hole range, but
fortunately it hasn't trigger any real problems now since ->map_blocks()
will fix the length. Fix this by supporting invalidating partial folios.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
---
fs/iomap/buffered-io.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 4da453394aaf..763deabe8331 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -644,6 +644,8 @@ void iomap_invalidate_folio(struct folio *folio, size_t offset, size_t len)
WARN_ON_ONCE(folio_test_writeback(folio));
folio_cancel_dirty(folio);
ifs_free(folio);
+ } else {
+ iomap_clear_range_dirty(folio, offset, len);
}
}
EXPORT_SYMBOL_GPL(iomap_invalidate_folio);
--
2.39.2