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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.

spi_lm70llp :  LM70-LLP parport-to-SPI adapter
==============================================

Supported board/chip:
  * National Semiconductor LM70 LLP evaluation board
    Datasheet: http://www.national.com/pf/LM/LM70.html

Author:
        Kaiwan N Billimoria <kaiwan@designergraphix.com>

Description
-----------
This driver provides glue code connecting a National Semiconductor LM70 LLP
temperature sensor evaluation board to the kernel's SPI core subsystem.

In effect, this driver turns the parallel port interface on the eval board
into a SPI bus with a single device, which will be driven by the generic
LM70 driver (drivers/hwmon/lm70.c).

The hardware interfacing on the LM70 LLP eval board is as follows:

   Parallel                 LM70 LLP
     Port      Direction   JP2 Header
   ----------- --------- ----------------
      D0     2      -         -
      D1     3     -->      V+   5
      D2     4     -->      V+   5
      D3     5     -->      V+   5
      D4     6     -->      V+   5
      D5     7     -->      nCS  8
      D6     8     -->      SCLK 3
      D7     9     -->      SI/O 5
     GND    25      -       GND  7
    Select  13     <--      SI/O 1
   ----------- --------- ----------------

Note that since the LM70 uses a "3-wire" variant of SPI, the SI/SO pin
is connected to both pin D7 (as Master Out) and Select (as Master In)
using an arrangment that lets either the parport or the LM70 pull the
pin low.  This can't be shared with true SPI devices, but other 3-wire
devices might share the same SI/SO pin.

The bitbanger routine in this driver (lm70_txrx) is called back from
the bound "hwmon/lm70" protocol driver through its sysfs hook, using a
spi_write_then_read() call.  It performs Mode 0 (SPI/Microwire) bitbanging.
The lm70 driver then inteprets the resulting digital temperature value
and exports it through sysfs.

A "gotcha": National Semiconductor's LM70 LLP eval board circuit schematic
shows that the SI/O line from the LM70 chip is connected to the base of a
transistor Q1 (and also a pullup, and a zener diode to D7); while the
collector is tied to VCC.

Interpreting this circuit, when the LM70 SI/O line is High (or tristate
and not grounded by the host via D7), the transistor conducts and switches
the collector to zero, which is reflected on pin 13 of the DB25 parport
connector.  When SI/O is Low (driven by the LM70 or the host) on the other
hand, the transistor is cut off and the voltage tied to it's collector is
reflected on pin 13 as a High level.

So: the getmiso inline routine in this driver takes this fact into account,
inverting the value read at pin 13.


Thanks to
---------
o David Brownell for mentoring the SPI-side driver development.
o Dr.Craig Hollabaugh for the (early) "manual" bitbanging driver version.
o Nadir Billimoria for help interpreting the circuit schematic.