[PATCH 6.12 131/567] fuse: Invalidate the page cache after FOPEN_DIRECT_IO write

Greg Kroah-Hartman
2026-01-06T17:21:34Z

From: Bernd Schubert <bschubert@ddn.com>

[ Upstream commit b359af8275a982a458e8df6c6beab1415be1f795 ]

generic_file_direct_write() also does this and has a large
comment about.

Reproducer here is xfstest's generic/209, which is exactly to
have competing DIO write and cached IO read.

Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/fuse/file.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index ec1b235df91d..4c5cf2d116d2 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1656,6 +1656,15 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
if (res > 0)
*ppos = pos;

+ if (res > 0 && write && fopen_direct_io) {
+ /*
+ * As in generic_file_direct_write(), invalidate after the
+ * write, to invalidate read-ahead cache that may have competed
+ * with the write.
+ */
+ invalidate_inode_pages2_range(mapping, idx_from, idx_to);
+ }
+
return res > 0 ? res : err;
}
EXPORT_SYMBOL_GPL(fuse_direct_io);
--
2.51.0