Joe Epstein a6cdb95450 mem_access: introduce P2M mem_access types
* Introduces access types for each page, giving independent read, write, and
  execute permissions for each page.  The permissions are restrictive from
  what the page type gives: for example, a p2m_type_ro page with an access of
  p2m_access_rw would have read-only permissions in total, as p2m_type_ro
  removed write access and p2m_access_rw removed execute access.

* Implements the access flag storage for EPT, moving some bits from P2M type,
  which had 10 bits of storage, to the four bits for access.

* Access flags are stored according to a loose consistency contract, where
  pages can be reset to the default access permissions at any time.  Right
  now, that happens on page type changes, where one would want to reevaluate
  whether permissions make sense for that page as they are anyway.

Signed-off-by: Joe Epstein <jepstein98@gmail.com>
Acked-by: Tim Deegan <Tim.Deegan@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>
2011-01-07 11:54:36 +00:00
2010-12-14 18:51:55 +00:00
2010-11-23 19:28:03 +00:00
2011-01-05 23:54:15 +00:00
2009-06-16 11:11:59 +01:00

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http://www.xen.org/

What is Xen?
============

Xen is a Virtual Machine Monitor (VMM) originally developed by the
Systems Research Group of the University of Cambridge Computer
Laboratory, as part of the UK-EPSRC funded XenoServers project.  Xen
is freely-distributable Open Source software, released under the GNU
GPL. Since its initial public release, Xen has grown a large
development community, spearheaded by xen.org (http://www.xen.org).

The 4.1 release offers excellent performance, hardware support and
enterprise-grade features such as x86_32-PAE, x86_64, SMP guests and
live relocation of VMs. Ports to Linux, NetBSD, FreeBSD and Solaris
are available from the community.

This file contains some quick-start instructions to install Xen on
your system. For full documentation, see the Xen User Manual. If this
is a pre-built release then you can find the manual at:
 dist/install/usr/share/doc/xen/pdf/user.pdf
If you have a source release, then 'make -C docs' will build the
manual at docs/pdf/user.pdf.

Quick-Start Guide
=================

First, there are a number of prerequisites for building a Xen source
release. Make sure you have all the following installed, either by
visiting the project webpage or installing a pre-built package
provided by your OS distributor:
    * GCC v3.4 or later
    * GNU Make
    * GNU Binutils
    * Development install of zlib (e.g., zlib-dev)
    * Development install of Python v2.3 or later (e.g., python-dev)
    * Development install of curses (e.g., libncurses-dev)
    * Development install of openssl (e.g., openssl-dev)
    * Development install of x11 (e.g. xorg-x11-dev)
    * bridge-utils package (/sbin/brctl)
    * iproute package (/sbin/ip)
    * hotplug or udev
    * GNU bison and GNU flex

Second, you need to acquire a suitable kernel for use in domain 0. If
possible you should use a kernel provided by your OS distributor. If
no suitable kernel is available from your OS distributor then refer to
http://wiki.xen.org/xenwiki/XenDom0Kernels for suggestions for
suitable kernels to use.

[NB. Unless noted otherwise, all the following steps should be
performed with root privileges.]

1. Download and untar the source tarball file. This will be a
   file named xen-unstable-src.tgz, or xen-$version-src.tgz.
   You can also pull the current version from the mercurial
   repository at http://xenbits.xen.org/

    # tar xzf xen-unstable-src.tgz

   Assuming you are using the unstable tree, this will
   untar into xen-unstable. The rest of the instructions
   use the unstable tree as an example, substitute the
   version for unstable.

2. cd to xen-unstable (or whatever you sensibly rename it to).

3. For the very first build, or if you want to destroy build trees,
   perform the following steps:

    # make world
    # make install

   This will create and install onto the local machine. It will build
   the xen binary (xen.gz), the tools and the documentation.

   You can override the destination for make install by setting DESTDIR
   to some value.

4. To rebuild an existing tree without modifying the config:
    # make dist

   This will build and install xen, tools, and docs into the local dist/
   directory.

   You can override the destination for make install by setting DISTDIR
   to some value.

   make install and make dist differ in that make install does the
   right things for your local machine (installing the appropriate
   version of hotplug or udev scripts, for example), but make dist
   includes all versions of those scripts, so that you can copy the dist
   directory to another machine and install from that distribution.
   
Python Runtime Libraries
========================

Xend (the Xen daemon) has the following runtime dependencies:

    * Python 2.3 or later.
      In some distros, the XML-aspects to the standard library
      (xml.dom.minidom etc) are broken out into a separate python-xml package.
      This is also required.
      In more recent versions of Debian and Ubuntu the XML-aspects are included
      in the base python package however (python-xml has been removed
      from Debian in squeeze and from Ubuntu in intrepid).

          URL:    http://www.python.org/
          Debian: python

    * For optional SSL support, pyOpenSSL:
          URL:    http://pyopenssl.sourceforge.net/
          Debian: python-pyopenssl

    * For optional PAM support, PyPAM:
          URL:    http://www.pangalactic.org/PyPAM/
          Debian: python-pam

    * For optional XenAPI support in XM, PyXML:
          URL:    http://codespeak.net/lxml/
	  Debian: python-lxml
          YUM:    python-lxml


Intel(R) Trusted Execution Technology Support
=============================================

Intel's technology for safer computing, Intel(R) Trusted Execution Technology
(Intel(R) TXT), defines platform-level enhancements that provide the building
blocks for creating trusted platforms.  For more information, see
http://www.intel.com/technology/security/.

Intel(R) TXT support is provided by the Trusted Boot (tboot) module in
conjunction with minimal logic in the Xen hypervisor.

Tboot is an open source, pre- kernel/VMM module that uses Intel(R) TXT to
perform a measured and verified launch of an OS kernel/VMM.

The Trusted Boot module is available from
http://sourceforge.net/projects/tboot.  This project hosts the code in a
mercurial repo at http://tboot.sourceforge.net/hg/tboot.hg and contains
tarballs of the source.  Instructions in the tboot README describe how
to modify grub.conf to use tboot to launch Xen.

There are optional targets as part of Xen's top-level makefile that will
download and build tboot: install-tboot, build-tboot, dist-tboot, clean-tboot.
These will download the latest tar file from the SourceForge site using wget,
then build/install/dist according to Xen's settings.
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