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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.

/*
 * symlink.c - operations for sysfs symlinks.
 */

#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/module.h>
#include <linux/kobject.h>
#include <linux/namei.h>
#include <asm/semaphore.h>

#include "sysfs.h"

static int object_depth(struct sysfs_dirent *sd)
{
	int depth = 0;

	for (; sd->s_parent; sd = sd->s_parent)
		depth++;

	return depth;
}

static int object_path_length(struct sysfs_dirent * sd)
{
	int length = 1;

	for (; sd->s_parent; sd = sd->s_parent)
		length += strlen(sd->s_name) + 1;

	return length;
}

static void fill_object_path(struct sysfs_dirent *sd, char *buffer, int length)
{
	--length;
	for (; sd->s_parent; sd = sd->s_parent) {
		int cur = strlen(sd->s_name);

		/* back up enough to print this bus id with '/' */
		length -= cur;
		strncpy(buffer + length, sd->s_name, cur);
		*(buffer + --length) = '/';
	}
}

/**
 *	sysfs_create_link - create symlink between two objects.
 *	@kobj:	object whose directory we're creating the link in.
 *	@target:	object we're pointing to.
 *	@name:		name of the symlink.
 */
int sysfs_create_link(struct kobject * kobj, struct kobject * target, const char * name)
{
	struct sysfs_dirent *parent_sd = NULL;
	struct sysfs_dirent *target_sd = NULL;
	struct sysfs_dirent *sd = NULL;
	struct sysfs_addrm_cxt acxt;
	int error;

	BUG_ON(!name);

	if (!kobj) {
		if (sysfs_mount && sysfs_mount->mnt_sb)
			parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
	} else
		parent_sd = kobj->sd;

	error = -EFAULT;
	if (!parent_sd)
		goto out_put;

	/* target->sd can go away beneath us but is protected with
	 * sysfs_assoc_lock.  Fetch target_sd from it.
	 */
	spin_lock(&sysfs_assoc_lock);
	if (target->sd)
		target_sd = sysfs_get(target->sd);
	spin_unlock(&sysfs_assoc_lock);

	error = -ENOENT;
	if (!target_sd)
		goto out_put;

	error = -ENOMEM;
	sd = sysfs_new_dirent(name, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);
	if (!sd)
		goto out_put;

	sd->s_elem.symlink.target_sd = target_sd;
	target_sd = NULL;	/* reference is now owned by the symlink */

	sysfs_addrm_start(&acxt, parent_sd);

	if (!sysfs_find_dirent(parent_sd, name)) {
		sysfs_add_one(&acxt, sd);
		sysfs_link_sibling(sd);
	}

	if (!sysfs_addrm_finish(&acxt)) {
		error = -EEXIST;
		goto out_put;
	}

	return 0;

 out_put:
	sysfs_put(target_sd);
	sysfs_put(sd);
	return error;
}


/**
 *	sysfs_remove_link - remove symlink in object's directory.
 *	@kobj:	object we're acting for.
 *	@name:	name of the symlink to remove.
 */

void sysfs_remove_link(struct kobject * kobj, const char * name)
{
	sysfs_hash_and_remove(kobj->sd, name);
}

static int sysfs_get_target_path(struct sysfs_dirent * parent_sd,
				 struct sysfs_dirent * target_sd, char *path)
{
	char * s;
	int depth, size;

	depth = object_depth(parent_sd);
	size = object_path_length(target_sd) + depth * 3 - 1;
	if (size > PATH_MAX)
		return -ENAMETOOLONG;

	pr_debug("%s: depth = %d, size = %d\n", __FUNCTION__, depth, size);

	for (s = path; depth--; s += 3)
		strcpy(s,"../");

	fill_object_path(target_sd, path, size);
	pr_debug("%s: path = '%s'\n", __FUNCTION__, path);

	return 0;
}

static int sysfs_getlink(struct dentry *dentry, char * path)
{
	struct sysfs_dirent *sd = dentry->d_fsdata;
	struct sysfs_dirent *parent_sd = sd->s_parent;
	struct sysfs_dirent *target_sd = sd->s_elem.symlink.target_sd;
	int error;

	mutex_lock(&sysfs_mutex);
	error = sysfs_get_target_path(parent_sd, target_sd, path);
	mutex_unlock(&sysfs_mutex);

	return error;
}

static void *sysfs_follow_link(struct dentry *dentry, struct nameidata *nd)
{
	int error = -ENOMEM;
	unsigned long page = get_zeroed_page(GFP_KERNEL);
	if (page)
		error = sysfs_getlink(dentry, (char *) page); 
	nd_set_link(nd, error ? ERR_PTR(error) : (char *)page);
	return NULL;
}

static void sysfs_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
{
	char *page = nd_get_link(nd);
	if (!IS_ERR(page))
		free_page((unsigned long)page);
}

const struct inode_operations sysfs_symlink_inode_operations = {
	.readlink = generic_readlink,
	.follow_link = sysfs_follow_link,
	.put_link = sysfs_put_link,
};


EXPORT_SYMBOL_GPL(sysfs_create_link);
EXPORT_SYMBOL_GPL(sysfs_remove_link);