vchan-unix

Xen Vchan implementation
README


This is an implementation of the Xen "libvchan" or "vchan" communication
protocol in OCaml. It allows fast inter-domain communication using shared
memory.

Linux configuration

Make sure your systems are properly configured. You may need to:

sudo modprobe xen-evtchn
sudo modprobe xen-gntdev
sudo modprobe xen-gntalloc
mount -t xenfs xenfs /proc/xen

To use in Linux

To connect as a server to a client with domid 'domid' and using
the string 'port' to denote the connection:

open Vchan_lwt_unix

open_server ~domid ~port ()
>>= fun (ic, oc) ->
Lwt_io.write_line oc "hello"
>>= fun () ->
Lwt_io.flush oc
>>= fun () ->
Lwt_io.close ic
>>= fun () ->
Lwt_io.close oc

To connect as a client, replace open_server with open_client.

To use the command-line

On both of your VMs, find their domain ids:

xenstore-read domid

On the domain with domid <server domid>, listen for a single connection from
<client domid> on <port>:

xencat -l <client domid> <port>

On the domain with domid <client domid>, connect to <server domid>:

xencat <server domid> <port>

So to transfer a file foo from domid 1 to domid 2:

On domain 2, listen for the connection and retrieve the file:

xencat -l 1 foo > copy-of-foo

On domain 1, transmit the file:

cat foo | xencat 2 foo
Install
Published
22 Oct 2020
Sources
vchan-v6.0.0.tbz
sha256=7a6cc89ff8ba7144d6cef3f36722f40deedb3cefff0f7be1b2f3b7b2a2b41747
sha512=0df7879cead12d37d7a16cc21af839fc26ba16532ced69313bb3b153f187e5f4586c8e34d59ee51265500e0f50febc1b8c01f9ba3703ddd18b6851f02f52c43a
Dependencies
Reverse Dependencies