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
27 Jun 2019
Sources
vchan-v4.0.3.tbz
sha256=881561336d1b52443512297e156586aa0ae4c8637f273b9316e873a35afabfa7
sha512=691394329b1cbd1c5c842b607fe7fd9ba5a959b501e75dfaf818d02a82d507399cba9a9e4e97c2c69ad1fec078f5f994b8dae539fef3946af6cb355b3eed5c60
Dependencies
Reverse Dependencies