virtio_fs: allow idmapped mounts

Allow idmapped mounts for virtiofs.
It's absolutely safe as for virtiofs we have the same
feature negotiation mechanism as for classical fuse
filesystems. This does not affect any existing
setups anyhow.

virtiofsd support:
https://gitlab.com/virtio-fs/virtiofsd/-/merge_requests/245

Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/fuse/virtio_fs.c b/fs/fuse/virtio_fs.c
index 2fee9eb5ad0bf402cb08a3cd1d3b5bd36bfccd47..b6bd6ab71f5d83ff8cc9d9d6a34e6cedb7273bea 100644 (file)
--- a/fs/fuse/virtio_fs.c
+++ b/fs/fuse/virtio_fs.c
@@ -1613,6 +1613,7 @@ static struct file_system_type virtio_fs_type = {
        .name           = "virtiofs",
        .init_fs_context = virtio_fs_init_fs_context,
        .kill_sb        = virtio_kill_sb,
+       .fs_flags       = FS_ALLOW_IDMAP,
 };
 
 static int virtio_fs_uevent(const struct kobject *kobj, struct kobj_uevent_env *env)