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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:

--------
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
--------
Merge of 2.6.x-xfs-melb:linux:29656b by kenmcd.

		High Precision Event Timer Driver for Linux

The High Precision Event Timer (HPET) hardware is the future replacement
for the 8254 and Real Time Clock (RTC) periodic timer functionality.
Each HPET can have up to 32 timers.  It is possible to configure the
first two timers as legacy replacements for 8254 and RTC periodic timers.
A specification done by Intel and Microsoft can be found at
<http://www.intel.com/technology/architecture/hpetspec.htm>.

The driver supports detection of HPET driver allocation and initialization
of the HPET before the driver module_init routine is called.  This enables
platform code which uses timer 0 or 1 as the main timer to intercept HPET
initialization.  An example of this initialization can be found in
arch/i386/kernel/time_hpet.c.

The driver provides two APIs which are very similar to the API found in
the rtc.c driver.  There is a user space API and a kernel space API.
An example user space program is provided below.

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <memory.h>
#include <malloc.h>
#include <time.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/time.h>
#include <linux/hpet.h>


extern void hpet_open_close(int, const char **);
extern void hpet_info(int, const char **);
extern void hpet_poll(int, const char **);
extern void hpet_fasync(int, const char **);
extern void hpet_read(int, const char **);

#include <sys/poll.h>
#include <sys/ioctl.h>
#include <signal.h>

struct hpet_command {
	char		*command;
	void		(*func)(int argc, const char ** argv);
} hpet_command[] = {
	{
		"open-close",
		hpet_open_close
	},
	{
		"info",
		hpet_info
	},
	{
		"poll",
		hpet_poll
	},
	{
		"fasync",
		hpet_fasync
	},
};

int
main(int argc, const char ** argv)
{
	int	i;

	argc--;
	argv++;

	if (!argc) {
		fprintf(stderr, "-hpet: requires command\n");
		return -1;
	}


	for (i = 0; i < (sizeof (hpet_command) / sizeof (hpet_command[0])); i++)
		if (!strcmp(argv[0], hpet_command[i].command)) {
			argc--;
			argv++;
			fprintf(stderr, "-hpet: executing %s\n",
				hpet_command[i].command);
			hpet_command[i].func(argc, argv);
			return 0;
		}

	fprintf(stderr, "do_hpet: command %s not implemented\n", argv[0]);

	return -1;
}

void
hpet_open_close(int argc, const char **argv)
{
	int	fd;

	if (argc != 1) {
		fprintf(stderr, "hpet_open_close: device-name\n");
		return;
	}

	fd = open(argv[0], O_RDONLY);
	if (fd < 0)
		fprintf(stderr, "hpet_open_close: open failed\n");
	else
		close(fd);

	return;
}

void
hpet_info(int argc, const char **argv)
{
}

void
hpet_poll(int argc, const char **argv)
{
	unsigned long		freq;
	int			iterations, i, fd;
	struct pollfd		pfd;
	struct hpet_info	info;
	struct timeval		stv, etv;
	struct timezone		tz;
	long			usec;

	if (argc != 3) {
		fprintf(stderr, "hpet_poll: device-name freq iterations\n");
		return;
	}

	freq = atoi(argv[1]);
	iterations = atoi(argv[2]);

	fd = open(argv[0], O_RDONLY);

	if (fd < 0) {
		fprintf(stderr, "hpet_poll: open of %s failed\n", argv[0]);
		return;
	}

	if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
		fprintf(stderr, "hpet_poll: HPET_IRQFREQ failed\n");
		goto out;
	}

	if (ioctl(fd, HPET_INFO, &info) < 0) {
		fprintf(stderr, "hpet_poll: failed to get info\n");
		goto out;
	}

	fprintf(stderr, "hpet_poll: info.hi_flags 0x%lx\n", info.hi_flags);

	if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
		fprintf(stderr, "hpet_poll: HPET_EPI failed\n");
		goto out;
	}

	if (ioctl(fd, HPET_IE_ON, 0) < 0) {
		fprintf(stderr, "hpet_poll, HPET_IE_ON failed\n");
		goto out;
	}

	pfd.fd = fd;
	pfd.events = POLLIN;

	for (i = 0; i < iterations; i++) {
		pfd.revents = 0;
		gettimeofday(&stv, &tz);
		if (poll(&pfd, 1, -1) < 0)
			fprintf(stderr, "hpet_poll: poll failed\n");
		else {
			long 	data;

			gettimeofday(&etv, &tz);
			usec = stv.tv_sec * 1000000 + stv.tv_usec;
			usec = (etv.tv_sec * 1000000 + etv.tv_usec) - usec;

			fprintf(stderr,
				"hpet_poll: expired time = 0x%lx\n", usec);

			fprintf(stderr, "hpet_poll: revents = 0x%x\n",
				pfd.revents);

			if (read(fd, &data, sizeof(data)) != sizeof(data)) {
				fprintf(stderr, "hpet_poll: read failed\n");
			}
			else
				fprintf(stderr, "hpet_poll: data 0x%lx\n",
					data);
		}
	}

out:
	close(fd);
	return;
}

static int hpet_sigio_count;

static void
hpet_sigio(int val)
{
	fprintf(stderr, "hpet_sigio: called\n");
	hpet_sigio_count++;
}

void
hpet_fasync(int argc, const char **argv)
{
	unsigned long		freq;
	int			iterations, i, fd, value;
	sig_t			oldsig;
	struct hpet_info	info;

	hpet_sigio_count = 0;
	fd = -1;

	if ((oldsig = signal(SIGIO, hpet_sigio)) == SIG_ERR) {
		fprintf(stderr, "hpet_fasync: failed to set signal handler\n");
		return;
	}

	if (argc != 3) {
		fprintf(stderr, "hpet_fasync: device-name freq iterations\n");
		goto out;
	}

	fd = open(argv[0], O_RDONLY);

	if (fd < 0) {
		fprintf(stderr, "hpet_fasync: failed to open %s\n", argv[0]);
		return;
	}


	if ((fcntl(fd, F_SETOWN, getpid()) == 1) ||
		((value = fcntl(fd, F_GETFL)) == 1) ||
		(fcntl(fd, F_SETFL, value | O_ASYNC) == 1)) {
		fprintf(stderr, "hpet_fasync: fcntl failed\n");
		goto out;
	}

	freq = atoi(argv[1]);
	iterations = atoi(argv[2]);

	if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
		fprintf(stderr, "hpet_fasync: HPET_IRQFREQ failed\n");
		goto out;
	}

	if (ioctl(fd, HPET_INFO, &info) < 0) {
		fprintf(stderr, "hpet_fasync: failed to get info\n");
		goto out;
	}

	fprintf(stderr, "hpet_fasync: info.hi_flags 0x%lx\n", info.hi_flags);

	if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
		fprintf(stderr, "hpet_fasync: HPET_EPI failed\n");
		goto out;
	}

	if (ioctl(fd, HPET_IE_ON, 0) < 0) {
		fprintf(stderr, "hpet_fasync, HPET_IE_ON failed\n");
		goto out;
	}

	for (i = 0; i < iterations; i++) {
		(void) pause();
		fprintf(stderr, "hpet_fasync: count = %d\n", hpet_sigio_count);
	}

out:
	signal(SIGIO, oldsig);

	if (fd >= 0)
		close(fd);

	return;
}

The kernel API has three interfaces exported from the driver:

	hpet_register(struct hpet_task *tp, int periodic)
	hpet_unregister(struct hpet_task *tp)
	hpet_control(struct hpet_task *tp, unsigned int cmd, unsigned long arg)

The kernel module using this interface fills in the ht_func and ht_data
members of the hpet_task structure before calling hpet_register.
hpet_control simply vectors to the hpet_ioctl routine and has the same
commands and respective arguments as the user API.  hpet_unregister
is used to terminate usage of the HPET timer reserved by hpet_register.