This introduces setupmapping and removemapping methods to server.rs,
passthrough.rs and filesystem.rs in order to support virtiofs dax mode
inside guest.
Since we don't really want the server.rs to know that it is dealing with
vhost-user specifically, this is making it more generic by adding a new
trait which has three functions map()/unmap()/sync() corresponding to
fs_slave_{map, unmap, sync}, server.rs will take anything that implements
the trait.
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Because the vhost_user_backend crate needs some changes to support
moving the process to a different mount namespace and perform a pivot
root, it is not possible to change '/' to the given shared directory.
This commit, as a temporary measure, let the code point at the given
shared directory.
The long term solution is to perform the mount namespace change and the
pivot root as this will provide greater security.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Add a "passthrough" file system implementation that just forwards its
requests to the appropriate system call.
This code has been ported over from crosvm commit
961461350c0b6824e5f20655031bf6c6bf6b7c30.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>