linux-imx

/******************************************************************************

 * Xen balloon driver - enables returning/claiming memory to/from Xen.

 *

 * Copyright (c) 2003, B Dragovic

 * Copyright (c) 2003-2004, M Williamson, K Fraser

 * Copyright (c) 2005 Dan M. Smith, IBM Corporation

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License version 2

 * as published by the Free Software Foundation; or, when distributed

 * separately from the Linux kernel or incorporated into other

 * software packages, subject to the following license:

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this source file (the "Software"), to deal in the Software without

 * restriction, including without limitation the rights to use, copy, modify,

 * merge, publish, distribute, sublicense, and/or sell copies of the Software,

 * and to permit persons to whom the Software is furnished to do so, subject to

 * the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

 * IN THE SOFTWARE.

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/mm_types.h>

#include <linux/init.h>

#include <linux/capability.h>

#include <linux/memory_hotplug.h>

​

#include <xen/xen.h>

#include <xen/interface/xen.h>

#include <xen/balloon.h>

#include <xen/xenbus.h>

#include <xen/features.h>

#include <xen/page.h>

#include <xen/mem-reservation.h>

​

#define PAGES2KB(_p) ((_p)<<(PAGE_SHIFT-10))

​

#define BALLOON_CLASS_NAME "xen_memory"

​

#ifdef CONFIG_MEMORY_HOTPLUG

u64 xen_saved_max_mem_size = 0;

#endif

​

static struct device balloon_dev;

​

static int register_balloon(struct device *dev);

​

/* React to a change in the target key */

static void watch_target(struct xenbus_watch *watch,