virtiofs: add a mount option to enable dax

Add a mount option to allow using dax with virtio_fs.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
new file mode 100644
index 000000000000..9660d01f49a5
--- /dev/null
+++ b/fs/fuse/dax.c
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * dax: direct host memory access
+ * Copyright (C) 2020 Red Hat, Inc.
+ */
+
+#include "fuse_i.h"
+
+#include <linux/dax.h>
+
+struct fuse_conn_dax {
+	/* DAX device */
+	struct dax_device *dev;
+};
+
+void fuse_dax_conn_free(struct fuse_conn *fc)
+{
+	kfree(fc->dax);
+}
+
+int fuse_dax_conn_alloc(struct fuse_conn *fc, struct dax_device *dax_dev)
+{
+	struct fuse_conn_dax *fcd;
+
+	if (!dax_dev)
+		return 0;
+
+	fcd = kzalloc(sizeof(*fcd), GFP_KERNEL);
+	if (!fcd)
+		return -ENOMEM;
+
+	fcd->dev = dax_dev;
+
+	fc->dax = fcd;
+	return 0;
+}