package xen-evtchn-unix

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Xen event channel bindings.

Install

Dune Dependency

Authors

Maintainers

Sources

xen-evtchn-2.0.0.tbz
sha256=be35584e50c664e87eadce2f61622c051102d2d34b459cb17e2811a0bfc88bfe
md5=4c34efff1b711816e8db0d730c044359

Description

These are needed for building Xen device drivers (e.g. mirage-block-xen)

Tags

org:mirage org:xapi-project

Published: 29 May 2017

README

ocaml-evtchn

Xen event channel interface for Mirage.

Event channels are the Xen equivalent of interrupts, used to signal when data (or space) is available for processing. There are 2 distinct implementations:

  1. a Xen shared-memory + hypercall protocol for kernelspace

  2. a binding to a set of libxc functions which access /dev/xen/evtchn for userspace

Implementation notes

The mirage-platform/xen tree contains a custom set of C stubs which implements the simple parts of the protocol (eg mask, unmask, notify). These stubs are referenced from the Eventchn module. The choice of stubs (userspace or kernelspace) is performed at binary link-time by the 'mirage' command-line tool (or manually), avoiding the need for another functor for these cases.

The more 'Activations' signature which has blocking functions is implemented in OCaml in both the mirage-platform/xen tree (Activations) and here (Unix_activations). Libraries must be functorised and the functor must be instantiated in the final program.

Dependencies (7)

  1. conf-xen build
  2. cmdliner
  3. lwt
  4. xen-evtchn = "2.0.0"
  5. jbuilder >= "1.0+beta9"
  6. ocamlfind build
  7. ocaml >= "4.00.0"

Dev Dependencies (1)

  1. ounit with-test

Used by (1)

  1. vchan-unix

Conflicts

None

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