From: Bernd Schubert <bschubert@ddn.com>
Date: Wed, 22 Oct 2025 22:21:17 +0000 (+0200)
Subject: fuse: Invalidate the page cache after FOPEN_DIRECT_IO write
X-Git-Tag: v6.19-rc1~110^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b359af8275a982a458e8df6c6beab1415be1f795;p=thirdparty%2Fkernel%2Flinux.git

fuse: Invalidate the page cache after FOPEN_DIRECT_IO write

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>
---

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 4d96e684d7363..b60f394df5a33 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1693,6 +1693,15 @@ 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);