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Update 2.6.x-xfs to 2.6.23-rc4.

Also update fs/xfs with external mainline changes.
There were 12 such missing commits that I detected:

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commit ad690ef9e690f6c31f7d310b09ef1314bcec9033
Author: Al Viro <viro@ftp.linux.org.uk>
    xfs ioctl __user annotations

commit 20c2df83d25c6a95affe6157a4c9cac4cf5ffaac
Author: Paul Mundt <lethal@linux-sh.org>
    mm: Remove slab destructors from kmem_cache_create().

commit d0217ac04ca6591841e5665f518e38064f4e65bd
Author: Nick Piggin <npiggin@suse.de>
    mm: fault feedback #1

commit 54cb8821de07f2ffcd28c380ce9b93d5784b40d7
Author: Nick Piggin <npiggin@suse.de>
    mm: merge populate and nopage into fault (fixes nonlinear)

commit d00806b183152af6d24f46f0c33f14162ca1262a
Author: Nick Piggin <npiggin@suse.de>
    mm: fix fault vs invalidate race for linear mappings

commit a569425512253992cc64ebf8b6d00a62f986db3e
Author: Christoph Hellwig <hch@infradead.org>
    knfsd: exportfs: add exportfs.h header

commit 831441862956fffa17b9801db37e6ea1650b0f69
Author: Rafael J. Wysocki <rjw@sisk.pl>
    Freezer: make kernel threads nonfreezable by default

commit 8e1f936b73150f5095448a0fee6d4f30a1f9001d
Author: Rusty Russell <rusty@rustcorp.com.au>
    mm: clean up and kernelify shrinker registration

commit 5ffc4ef45b3b0a57872f631b4e4ceb8ace0d7496
Author: Jens Axboe <jens.axboe@oracle.com>
    sendfile: remove .sendfile from filesystems that use generic_file_sendfile()

commit 8bb7844286fb8c9fce6f65d8288aeb09d03a5e0d
Author: Rafael J. Wysocki <rjw@sisk.pl>
    Add suspend-related notifications for CPU hotplug

commit 59c51591a0ac7568824f541f57de967e88adaa07
Author: Michael Opdenacker <michael@free-electrons.com>
    Fix occurrences of "the the "

commit 0ceb331433e8aad9c5f441a965d7c681f8b9046f
Author: Dmitriy Monakhov <dmonakhov@openvz.org>
    mm: move common segment checks to separate helper function
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Merge of 2.6.x-xfs-melb:linux:29656b by kenmcd.

This is an explanation of what i2c is, and what is supported in this package.

I2C and SMBus
=============

I2C (pronounce: I squared C) is a protocol developed by Philips. It is a 
slow two-wire protocol (variable speed, up to 400 kHz), with a high speed
extension (3.4 MHz).  It provides an inexpensive bus for connecting many
types of devices with infrequent or low bandwidth communications needs.
I2C is widely used with embedded systems.  Some systems use variants that
don't meet branding requirements, and so are not advertised as being I2C.

SMBus (System Management Bus) is based on the I2C protocol, and is mostly
a subset of I2C protocols and signaling.  Many I2C devices will work on an
SMBus, but some SMBus protocols add semantics beyond what is required to
achieve I2C branding.  Modern PC mainboards rely on SMBus.  The most common
devices connected through SMBus are RAM modules configured using I2C EEPROMs,
and hardware monitoring chips.

Because the SMBus is mostly a subset of the generalized I2C bus, we can
use its protocols on many I2C systems.  However, there are systems that don't
meet both SMBus and I2C electrical constraints; and others which can't
implement all the common SMBus protocol semantics or messages.


Terminology
===========

When we talk about I2C, we use the following terms:
  Bus    -> Algorithm
            Adapter
  Device -> Driver
            Client

An Algorithm driver contains general code that can be used for a whole class
of I2C adapters. Each specific adapter driver depends on one algorithm
driver.

A Driver driver (yes, this sounds ridiculous, sorry) contains the general
code to access some type of device. Each detected device gets its own
data in the Client structure. Usually, Driver and Client are more closely
integrated than Algorithm and Adapter.

For a given configuration, you will need a driver for your I2C bus (usually
a separate Adapter and Algorithm driver), and drivers for your I2C devices
(usually one driver for each device). There are no I2C device drivers
in this package. See the lm_sensors project http://www.lm-sensors.nu
for device drivers.

At this time, Linux only operates I2C (or SMBus) in master mode; you can't
use these APIs to make a Linux system behave as a slave/device, either to
speak a custom protocol or to emulate some other device.


Included Bus Drivers
====================
Note that only stable drivers are patched into the kernel by 'mkpatch'.


Base modules
------------

i2c-core: The basic I2C code, including the /proc/bus/i2c* interface
i2c-dev:  The /dev/i2c-* interface
i2c-proc: The /proc/sys/dev/sensors interface for device (client) drivers

Algorithm drivers
-----------------

i2c-algo-bit:    A bit-banging algorithm
i2c-algo-pcf:    A PCF 8584 style algorithm
i2c-algo-ibm_ocp: An algorithm for the I2C device in IBM 4xx processors (NOT BUILT BY DEFAULT)

Adapter drivers
---------------

i2c-elektor:     Elektor ISA card (uses i2c-algo-pcf)
i2c-elv:         ELV parallel port adapter (uses i2c-algo-bit)
i2c-pcf-epp:     PCF8584 on a EPP parallel port (uses i2c-algo-pcf) (NOT mkpatched)
i2c-philips-par: Philips style parallel port adapter (uses i2c-algo-bit)
i2c-adap-ibm_ocp: IBM 4xx processor I2C device (uses i2c-algo-ibm_ocp) (NOT BUILT BY DEFAULT)
i2c-pport:       Primitive parallel port adapter (uses i2c-algo-bit)
i2c-velleman:    Velleman K8000 parallel port adapter (uses i2c-algo-bit)