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Up to [Development] / linux-2.6-xfs-all / kernel

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.

/*
 * A simple kernel FIFO implementation.
 *
 * Copyright (C) 2004 Stelian Pop <stelian@popies.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/kfifo.h>
#include <linux/log2.h>

/**
 * kfifo_init - allocates a new FIFO using a preallocated buffer
 * @buffer: the preallocated buffer to be used.
 * @size: the size of the internal buffer, this have to be a power of 2.
 * @gfp_mask: get_free_pages mask, passed to kmalloc()
 * @lock: the lock to be used to protect the fifo buffer
 *
 * Do NOT pass the kfifo to kfifo_free() after use! Simply free the
 * &struct kfifo with kfree().
 */
struct kfifo *kfifo_init(unsigned char *buffer, unsigned int size,
			 gfp_t gfp_mask, spinlock_t *lock)
{
	struct kfifo *fifo;

	/* size must be a power of 2 */
	BUG_ON(!is_power_of_2(size));

	fifo = kmalloc(sizeof(struct kfifo), gfp_mask);
	if (!fifo)
		return ERR_PTR(-ENOMEM);

	fifo->buffer = buffer;
	fifo->size = size;
	fifo->in = fifo->out = 0;
	fifo->lock = lock;

	return fifo;
}
EXPORT_SYMBOL(kfifo_init);

/**
 * kfifo_alloc - allocates a new FIFO and its internal buffer
 * @size: the size of the internal buffer to be allocated.
 * @gfp_mask: get_free_pages mask, passed to kmalloc()
 * @lock: the lock to be used to protect the fifo buffer
 *
 * The size will be rounded-up to a power of 2.
 */
struct kfifo *kfifo_alloc(unsigned int size, gfp_t gfp_mask, spinlock_t *lock)
{
	unsigned char *buffer;
	struct kfifo *ret;

	/*
	 * round up to the next power of 2, since our 'let the indices
	 * wrap' tachnique works only in this case.
	 */
	if (size & (size - 1)) {
		BUG_ON(size > 0x80000000);
		size = roundup_pow_of_two(size);
	}

	buffer = kmalloc(size, gfp_mask);
	if (!buffer)
		return ERR_PTR(-ENOMEM);

	ret = kfifo_init(buffer, size, gfp_mask, lock);

	if (IS_ERR(ret))
		kfree(buffer);

	return ret;
}
EXPORT_SYMBOL(kfifo_alloc);

/**
 * kfifo_free - frees the FIFO
 * @fifo: the fifo to be freed.
 */
void kfifo_free(struct kfifo *fifo)
{
	kfree(fifo->buffer);
	kfree(fifo);
}
EXPORT_SYMBOL(kfifo_free);

/**
 * __kfifo_put - puts some data into the FIFO, no locking version
 * @fifo: the fifo to be used.
 * @buffer: the data to be added.
 * @len: the length of the data to be added.
 *
 * This function copies at most @len bytes from the @buffer into
 * the FIFO depending on the free space, and returns the number of
 * bytes copied.
 *
 * Note that with only one concurrent reader and one concurrent
 * writer, you don't need extra locking to use these functions.
 */
unsigned int __kfifo_put(struct kfifo *fifo,
			 unsigned char *buffer, unsigned int len)
{
	unsigned int l;

	len = min(len, fifo->size - fifo->in + fifo->out);

	/*
	 * Ensure that we sample the fifo->out index -before- we
	 * start putting bytes into the kfifo.
	 */

	smp_mb();

	/* first put the data starting from fifo->in to buffer end */
	l = min(len, fifo->size - (fifo->in & (fifo->size - 1)));
	memcpy(fifo->buffer + (fifo->in & (fifo->size - 1)), buffer, l);

	/* then put the rest (if any) at the beginning of the buffer */
	memcpy(fifo->buffer, buffer + l, len - l);

	/*
	 * Ensure that we add the bytes to the kfifo -before-
	 * we update the fifo->in index.
	 */

	smp_wmb();

	fifo->in += len;

	return len;
}
EXPORT_SYMBOL(__kfifo_put);

/**
 * __kfifo_get - gets some data from the FIFO, no locking version
 * @fifo: the fifo to be used.
 * @buffer: where the data must be copied.
 * @len: the size of the destination buffer.
 *
 * This function copies at most @len bytes from the FIFO into the
 * @buffer and returns the number of copied bytes.
 *
 * Note that with only one concurrent reader and one concurrent
 * writer, you don't need extra locking to use these functions.
 */
unsigned int __kfifo_get(struct kfifo *fifo,
			 unsigned char *buffer, unsigned int len)
{
	unsigned int l;

	len = min(len, fifo->in - fifo->out);

	/*
	 * Ensure that we sample the fifo->in index -before- we
	 * start removing bytes from the kfifo.
	 */

	smp_rmb();

	/* first get the data from fifo->out until the end of the buffer */
	l = min(len, fifo->size - (fifo->out & (fifo->size - 1)));
	memcpy(buffer, fifo->buffer + (fifo->out & (fifo->size - 1)), l);

	/* then get the rest (if any) from the beginning of the buffer */
	memcpy(buffer + l, fifo->buffer, len - l);

	/*
	 * Ensure that we remove the bytes from the kfifo -before-
	 * we update the fifo->out index.
	 */

	smp_mb();

	fifo->out += len;

	return len;
}
EXPORT_SYMBOL(__kfifo_get);