[net-next-2.6.git] / arch / s390 / mm / cmm.c

/*
 *  arch/s390/mm/cmm.c
 *
 *  S390 version
 *    Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
 *
 *  Collaborative memory management interface.
 */

#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/sched.h>
#include <linux/sysctl.h>
#include <linux/ctype.h>
#include <linux/swap.h>
#include <linux/kthread.h>
#include <linux/oom.h>
#include <linux/suspend.h>

#include <asm/pgalloc.h>
#include <asm/uaccess.h>
#include <asm/diag.h>

static char *sender = "VMRMSVM";
module_param(sender, charp, 0400);
MODULE_PARM_DESC(sender,
		 "Guest name that may send SMSG messages (default VMRMSVM)");

#include "../../../drivers/s390/net/smsgiucv.h"

#define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2)

struct cmm_page_array {
	struct cmm_page_array *next;
	unsigned long index;
	unsigned long pages[CMM_NR_PAGES];
};

static long cmm_pages;
static long cmm_timed_pages;
static volatile long cmm_pages_target;
static volatile long cmm_timed_pages_target;
static long cmm_timeout_pages;
static long cmm_timeout_seconds;
static int cmm_suspended;

static struct cmm_page_array *cmm_page_list;
static struct cmm_page_array *cmm_timed_page_list;
static DEFINE_SPINLOCK(cmm_lock);

static struct task_struct *cmm_thread_ptr;
static wait_queue_head_t cmm_thread_wait;
static struct timer_list cmm_timer;

static void cmm_timer_fn(unsigned long);
static void cmm_set_timer(void);

static long
cmm_alloc_pages(long nr, long *counter, struct cmm_page_array **list)
{
	struct cmm_page_array *pa, *npa;
	unsigned long addr;

	while (nr) {
		addr = __get_free_page(GFP_NOIO);
		if (!addr)
			break;
		spin_lock(&cmm_lock);
		pa = *list;
		if (!pa || pa->index >= CMM_NR_PAGES) {
			/* Need a new page for the page list. */
			spin_unlock(&cmm_lock);
			npa = (struct cmm_page_array *)
				__get_free_page(GFP_NOIO);
			if (!npa) {
				free_page(addr);
				break;
			}
			spin_lock(&cmm_lock);
			pa = *list;
			if (!pa || pa->index >= CMM_NR_PAGES) {
				npa->next = pa;
				npa->index = 0;
				pa = npa;
				*list = pa;
			} else
				free_page((unsigned long) npa);
		}
		diag10(addr);
		pa->pages[pa->index++] = addr;
		(*counter)++;
		spin_unlock(&cmm_lock);
		nr--;
	}
	return nr;
}

static long
cmm_free_pages(long nr, long *counter, struct cmm_page_array **list)
{
	struct cmm_page_array *pa;
	unsigned long addr;

	spin_lock(&cmm_lock);
	pa = *list;
	while (nr) {
		if (!pa || pa->index <= 0)
			break;
		addr = pa->pages[--pa->index];
		if (pa->index == 0) {
			pa = pa->next;
			free_page((unsigned long) *list);
			*list = pa;
		}
		free_page(addr);
		(*counter)--;
		nr--;
	}
	spin_unlock(&cmm_lock);
	return nr;
}

static int cmm_oom_notify(struct notifier_block *self,
			  unsigned long dummy, void *parm)
{
	unsigned long *freed = parm;
	long nr = 256;

	nr = cmm_free_pages(nr, &cmm_timed_pages, &cmm_timed_page_list);
	if (nr > 0)
		nr = cmm_free_pages(nr, &cmm_pages, &cmm_page_list);
	cmm_pages_target = cmm_pages;
	cmm_timed_pages_target = cmm_timed_pages;
	*freed += 256 - nr;
	return NOTIFY_OK;
}

static struct notifier_block cmm_oom_nb = {
	.notifier_call = cmm_oom_notify
};

static int
cmm_thread(void *dummy)
{
	int rc;

	while (1) {
		rc = wait_event_interruptible(cmm_thread_wait,
			(!cmm_suspended && (cmm_pages != cmm_pages_target ||
			 cmm_timed_pages != cmm_timed_pages_target)) ||
			 kthread_should_stop());
		if (kthread_should_stop() || rc == -ERESTARTSYS) {
			cmm_pages_target = cmm_pages;
			cmm_timed_pages_target = cmm_timed_pages;
			break;
		}
		if (cmm_pages_target > cmm_pages) {
			if (cmm_alloc_pages(1, &cmm_pages, &cmm_page_list))
				cmm_pages_target = cmm_pages;
		} else if (cmm_pages_target < cmm_pages) {
			cmm_free_pages(1, &cmm_pages, &cmm_page_list);
		}
		if (cmm_timed_pages_target > cmm_timed_pages) {
			if (cmm_alloc_pages(1, &cmm_timed_pages,
					   &cmm_timed_page_list))
				cmm_timed_pages_target = cmm_timed_pages;
		} else if (cmm_timed_pages_target < cmm_timed_pages) {
			cmm_free_pages(1, &cmm_timed_pages,
			       	       &cmm_timed_page_list);
		}
		if (cmm_timed_pages > 0 && !timer_pending(&cmm_timer))
			cmm_set_timer();
	}
	return 0;
}

static void
cmm_kick_thread(void)
{
	wake_up(&cmm_thread_wait);
}

static void
cmm_set_timer(void)
{
	if (cmm_timed_pages_target <= 0 || cmm_timeout_seconds <= 0) {
		if (timer_pending(&cmm_timer))
			del_timer(&cmm_timer);
		return;
	}
	if (timer_pending(&cmm_timer)) {
		if (mod_timer(&cmm_timer, jiffies + cmm_timeout_seconds*HZ))
			return;
	}
	cmm_timer.function = cmm_timer_fn;
	cmm_timer.data = 0;
	cmm_timer.expires = jiffies + cmm_timeout_seconds*HZ;
	add_timer(&cmm_timer);
}

static void
cmm_timer_fn(unsigned long ignored)
{
	long nr;

	nr = cmm_timed_pages_target - cmm_timeout_pages;
	if (nr < 0)
		cmm_timed_pages_target = 0;
	else
		cmm_timed_pages_target = nr;
	cmm_kick_thread();
	cmm_set_timer();
}

void
cmm_set_pages(long nr)
{
	cmm_pages_target = nr;
	cmm_kick_thread();
}

long
cmm_get_pages(void)
{
	return cmm_pages;
}

void
cmm_add_timed_pages(long nr)
{
	cmm_timed_pages_target += nr;
	cmm_kick_thread();
}

long
cmm_get_timed_pages(void)
{
	return cmm_timed_pages;
}

void
cmm_set_timeout(long nr, long seconds)
{
	cmm_timeout_pages = nr;
	cmm_timeout_seconds = seconds;
	cmm_set_timer();
}

static int
cmm_skip_blanks(char *cp, char **endp)
{
	char *str;

	for (str = cp; *str == ' ' || *str == '\t'; str++);
	*endp = str;
	return str != cp;
}

#ifdef CONFIG_CMM_PROC

static struct ctl_table cmm_table[];

static int
cmm_pages_handler(ctl_table *ctl, int write,
		  void __user *buffer, size_t *lenp, loff_t *ppos)
{
	char buf[16], *p;
	long nr;
	int len;

	if (!*lenp || (*ppos && !write)) {
		*lenp = 0;
		return 0;
	}

	if (write) {
		len = *lenp;
		if (copy_from_user(buf, buffer,
				   len > sizeof(buf) ? sizeof(buf) : len))
			return -EFAULT;
		buf[sizeof(buf) - 1] = '\0';
		cmm_skip_blanks(buf, &p);
		nr = simple_strtoul(p, &p, 0);
		if (ctl == &cmm_table[0])
			cmm_set_pages(nr);
		else
			cmm_add_timed_pages(nr);
	} else {
		if (ctl == &cmm_table[0])
			nr = cmm_get_pages();
		else
			nr = cmm_get_timed_pages();
		len = sprintf(buf, "%ld\n", nr);
		if (len > *lenp)
			len = *lenp;
		if (copy_to_user(buffer, buf, len))
			return -EFAULT;
	}
	*lenp = len;
	*ppos += len;
	return 0;
}

static int
cmm_timeout_handler(ctl_table *ctl, int write,
		    void __user *buffer, size_t *lenp, loff_t *ppos)
{
	char buf[64], *p;
	long nr, seconds;
	int len;

	if (!*lenp || (*ppos && !write)) {
		*lenp = 0;
		return 0;
	}

	if (write) {
		len = *lenp;
		if (copy_from_user(buf, buffer,
				   len > sizeof(buf) ? sizeof(buf) : len))
			return -EFAULT;
		buf[sizeof(buf) - 1] = '\0';
		cmm_skip_blanks(buf, &p);
		nr = simple_strtoul(p, &p, 0);
		cmm_skip_blanks(p, &p);
		seconds = simple_strtoul(p, &p, 0);
		cmm_set_timeout(nr, seconds);
	} else {
		len = sprintf(buf, "%ld %ld\n",
			      cmm_timeout_pages, cmm_timeout_seconds);
		if (len > *lenp)
			len = *lenp;
		if (copy_to_user(buffer, buf, len))
			return -EFAULT;
	}
	*lenp = len;
	*ppos += len;
	return 0;
}

static struct ctl_table cmm_table[] = {
	{
		.procname	= "cmm_pages",
		.mode		= 0644,
		.proc_handler	= cmm_pages_handler,
	},
	{
		.procname	= "cmm_timed_pages",
		.mode		= 0644,
		.proc_handler	= cmm_pages_handler,
	},
	{
		.procname	= "cmm_timeout",
		.mode		= 0644,
		.proc_handler	= cmm_timeout_handler,
	},
	{ }
};

static struct ctl_table cmm_dir_table[] = {
	{
		.procname	= "vm",
		.maxlen		= 0,
		.mode		= 0555,
		.child		= cmm_table,
	},
	{ }
};
#endif

#ifdef CONFIG_CMM_IUCV
#define SMSG_PREFIX "CMM"
static void
cmm_smsg_target(const char *from, char *msg)
{
	long nr, seconds;

	if (strlen(sender) > 0 && strcmp(from, sender) != 0)
		return;
	if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg))
		return;
	if (strncmp(msg, "SHRINK", 6) == 0) {
		if (!cmm_skip_blanks(msg + 6, &msg))
			return;
		nr = simple_strtoul(msg, &msg, 0);
		cmm_skip_blanks(msg, &msg);
		if (*msg == '\0')
			cmm_set_pages(nr);
	} else if (strncmp(msg, "RELEASE", 7) == 0) {
		if (!cmm_skip_blanks(msg + 7, &msg))
			return;
		nr = simple_strtoul(msg, &msg, 0);
		cmm_skip_blanks(msg, &msg);
		if (*msg == '\0')
			cmm_add_timed_pages(nr);
	} else if (strncmp(msg, "REUSE", 5) == 0) {
		if (!cmm_skip_blanks(msg + 5, &msg))
			return;
		nr = simple_strtoul(msg, &msg, 0);
		if (!cmm_skip_blanks(msg, &msg))
			return;
		seconds = simple_strtoul(msg, &msg, 0);
		cmm_skip_blanks(msg, &msg);
		if (*msg == '\0')
			cmm_set_timeout(nr, seconds);
	}
}
#endif

static struct ctl_table_header *cmm_sysctl_header;

static int cmm_suspend(void)
{
	cmm_suspended = 1;
	cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list);
	cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list);
	return 0;
}

static int cmm_resume(void)
{
	cmm_suspended = 0;
	cmm_kick_thread();
	return 0;
}

static int cmm_power_event(struct notifier_block *this,
			   unsigned long event, void *ptr)
{
	switch (event) {
	case PM_POST_HIBERNATION:
		return cmm_resume();
	case PM_HIBERNATION_PREPARE:
		return cmm_suspend();
	default:
		return NOTIFY_DONE;
	}
}

static struct notifier_block cmm_power_notifier = {
	.notifier_call = cmm_power_event,
};

static int
cmm_init (void)
{
	int rc = -ENOMEM;

#ifdef CONFIG_CMM_PROC
	cmm_sysctl_header = register_sysctl_table(cmm_dir_table);
	if (!cmm_sysctl_header)
		goto out_sysctl;
#endif
#ifdef CONFIG_CMM_IUCV
	rc = smsg_register_callback(SMSG_PREFIX, cmm_smsg_target);
	if (rc < 0)
		goto out_smsg;
#endif
	rc = register_oom_notifier(&cmm_oom_nb);
	if (rc < 0)
		goto out_oom_notify;
	rc = register_pm_notifier(&cmm_power_notifier);
	if (rc)
		goto out_pm;
	init_waitqueue_head(&cmm_thread_wait);
	init_timer(&cmm_timer);
	cmm_thread_ptr = kthread_run(cmm_thread, NULL, "cmmthread");
	rc = IS_ERR(cmm_thread_ptr) ? PTR_ERR(cmm_thread_ptr) : 0;
	if (rc)
		goto out_kthread;
	return 0;

out_kthread:
	unregister_pm_notifier(&cmm_power_notifier);
out_pm:
	unregister_oom_notifier(&cmm_oom_nb);
out_oom_notify:
#ifdef CONFIG_CMM_IUCV
	smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
out_smsg:
#endif
#ifdef CONFIG_CMM_PROC
	unregister_sysctl_table(cmm_sysctl_header);
out_sysctl:
#endif
	return rc;
}

static void
cmm_exit(void)
{
	kthread_stop(cmm_thread_ptr);
	unregister_pm_notifier(&cmm_power_notifier);
	unregister_oom_notifier(&cmm_oom_nb);
	cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list);
	cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list);
#ifdef CONFIG_CMM_PROC
	unregister_sysctl_table(cmm_sysctl_header);
#endif
#ifdef CONFIG_CMM_IUCV
	smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
#endif
}

module_init(cmm_init);
module_exit(cmm_exit);

EXPORT_SYMBOL(cmm_set_pages);
EXPORT_SYMBOL(cmm_get_pages);
EXPORT_SYMBOL(cmm_add_timed_pages);
EXPORT_SYMBOL(cmm_get_timed_pages);
EXPORT_SYMBOL(cmm_set_timeout);

MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* arch/s390/mm/cmm.c
	3	*
	4	* S390 version
	5	* Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
	6	* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
	7	*
	8	* Collaborative memory management interface.
	9	*/
	10
1da177e4 LT	11	#include <linux/errno.h>
	12	#include <linux/fs.h>
	13	#include <linux/init.h>
	14	#include <linux/module.h>
5a0e3ad6	15	#include <linux/gfp.h>
1da177e4 LT	16	#include <linux/sched.h>
	17	#include <linux/sysctl.h>
	18	#include <linux/ctype.h>
8bc719d3	19	#include <linux/swap.h>
e8216dee	20	#include <linux/kthread.h>
5a3135c2	21	#include <linux/oom.h>
52b169c8	22	#include <linux/suspend.h>
1da177e4 LT	23
	24	#include <asm/pgalloc.h>
	25	#include <asm/uaccess.h>
0a87c5cf	26	#include <asm/diag.h>
1da177e4	27
15439d74	28	static char *sender = "VMRMSVM";
447570cf	29	module_param(sender, charp, 0400);
15439d74 MS	30	MODULE_PARM_DESC(sender,
	31	"Guest name that may send SMSG messages (default VMRMSVM)");
	32
1da177e4 LT	33	#include "../../../drivers/s390/net/smsgiucv.h"
	34
	35	#define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2)
	36
	37	struct cmm_page_array {
	38	struct cmm_page_array *next;
	39	unsigned long index;
	40	unsigned long pages[CMM_NR_PAGES];
	41	};
	42
8bc719d3 MS	43	static long cmm_pages;
	44	static long cmm_timed_pages;
	45	static volatile long cmm_pages_target;
	46	static volatile long cmm_timed_pages_target;
	47	static long cmm_timeout_pages;
	48	static long cmm_timeout_seconds;
52b169c8	49	static int cmm_suspended;
1da177e4	50
8bc719d3 MS	51	static struct cmm_page_array *cmm_page_list;
	52	static struct cmm_page_array *cmm_timed_page_list;
	53	static DEFINE_SPINLOCK(cmm_lock);
1da177e4	54
e8216dee	55	static struct task_struct *cmm_thread_ptr;
1da177e4 LT	56	static wait_queue_head_t cmm_thread_wait;
	57	static struct timer_list cmm_timer;
	58
	59	static void cmm_timer_fn(unsigned long);
	60	static void cmm_set_timer(void);
	61
1da177e4	62	static long
8bc719d3	63	cmm_alloc_pages(long nr, long counter, struct cmm_page_array *list)
1da177e4	64	{
8bc719d3 MS	65	struct cmm_page_array pa, npa;
8bc719d3 MS	66	unsigned long addr;
1da177e4	67
8bc719d3 MS	68	while (nr) {
	69	addr = __get_free_page(GFP_NOIO);
	70	if (!addr)
1da177e4	71	break;
8bc719d3 MS	72	spin_lock(&cmm_lock);
8bc719d3 MS	73	pa = *list;
1da177e4 LT	74	if (!pa \|\| pa->index >= CMM_NR_PAGES) {
1da177e4 LT	75	/* Need a new page for the page list. */
8bc719d3 MS	76	spin_unlock(&cmm_lock);
8bc719d3 MS	77	npa = (struct cmm_page_array *)
1da177e4	78	__get_free_page(GFP_NOIO);
8bc719d3 MS	79	if (!npa) {
8bc719d3 MS	80	free_page(addr);
1da177e4 LT	81	break;
1da177e4 LT	82	}
8bc719d3 MS	83	spin_lock(&cmm_lock);
	84	pa = *list;
	85	if (!pa \|\| pa->index >= CMM_NR_PAGES) {
	86	npa->next = pa;
	87	npa->index = 0;
	88	pa = npa;
	89	*list = pa;
	90	} else
	91	free_page((unsigned long) npa);
1da177e4	92	}
8bc719d3 MS	93	diag10(addr);
8bc719d3 MS	94	pa->pages[pa->index++] = addr;
1da177e4	95	(*counter)++;
8bc719d3 MS	96	spin_unlock(&cmm_lock);
8bc719d3 MS	97	nr--;
1da177e4	98	}
8bc719d3	99	return nr;
1da177e4 LT	100	}
1da177e4 LT	101
8bc719d3 MS	102	static long
8bc719d3 MS	103	cmm_free_pages(long nr, long counter, struct cmm_page_array *list)
1da177e4 LT	104	{
1da177e4 LT	105	struct cmm_page_array *pa;
8bc719d3	106	unsigned long addr;
1da177e4	107
8bc719d3	108	spin_lock(&cmm_lock);
1da177e4	109	pa = *list;
8bc719d3	110	while (nr) {
1da177e4 LT	111	if (!pa \|\| pa->index <= 0)
1da177e4 LT	112	break;
8bc719d3	113	addr = pa->pages[--pa->index];
1da177e4 LT	114	if (pa->index == 0) {
	115	pa = pa->next;
	116	free_page((unsigned long) *list);
	117	*list = pa;
	118	}
8bc719d3	119	free_page(addr);
1da177e4	120	(*counter)--;
8bc719d3	121	nr--;
1da177e4	122	}
8bc719d3 MS	123	spin_unlock(&cmm_lock);
8bc719d3 MS	124	return nr;
1da177e4 LT	125	}
1da177e4 LT	126
8bc719d3 MS	127	static int cmm_oom_notify(struct notifier_block *self,
	128	unsigned long dummy, void *parm)
	129	{
	130	unsigned long *freed = parm;
	131	long nr = 256;
	132
	133	nr = cmm_free_pages(nr, &cmm_timed_pages, &cmm_timed_page_list);
	134	if (nr > 0)
	135	nr = cmm_free_pages(nr, &cmm_pages, &cmm_page_list);
	136	cmm_pages_target = cmm_pages;
	137	cmm_timed_pages_target = cmm_timed_pages;
	138	*freed += 256 - nr;
	139	return NOTIFY_OK;
	140	}
	141
	142	static struct notifier_block cmm_oom_nb = {
	143	.notifier_call = cmm_oom_notify
	144	};
	145
1da177e4 LT	146	static int
	147	cmm_thread(void *dummy)
	148	{
	149	int rc;
	150
1da177e4 LT	151	while (1) {
1da177e4 LT	152	rc = wait_event_interruptible(cmm_thread_wait,
52b169c8 MS	153	(!cmm_suspended && (cmm_pages != cmm_pages_target \|\|
	154	cmm_timed_pages != cmm_timed_pages_target)) \|\|
	155	kthread_should_stop());
e8216dee	156	if (kthread_should_stop() \|\| rc == -ERESTARTSYS) {
1da177e4 LT	157	cmm_pages_target = cmm_pages;
	158	cmm_timed_pages_target = cmm_timed_pages;
	159	break;
	160	}
	161	if (cmm_pages_target > cmm_pages) {
	162	if (cmm_alloc_pages(1, &cmm_pages, &cmm_page_list))
	163	cmm_pages_target = cmm_pages;
	164	} else if (cmm_pages_target < cmm_pages) {
	165	cmm_free_pages(1, &cmm_pages, &cmm_page_list);
	166	}
	167	if (cmm_timed_pages_target > cmm_timed_pages) {
	168	if (cmm_alloc_pages(1, &cmm_timed_pages,
	169	&cmm_timed_page_list))
	170	cmm_timed_pages_target = cmm_timed_pages;
	171	} else if (cmm_timed_pages_target < cmm_timed_pages) {
	172	cmm_free_pages(1, &cmm_timed_pages,
	173	&cmm_timed_page_list);
	174	}
	175	if (cmm_timed_pages > 0 && !timer_pending(&cmm_timer))
	176	cmm_set_timer();
	177	}
	178	return 0;
	179	}
	180
1da177e4 LT	181	static void
	182	cmm_kick_thread(void)
	183	{
1da177e4 LT	184	wake_up(&cmm_thread_wait);
	185	}
	186
	187	static void
	188	cmm_set_timer(void)
	189	{
	190	if (cmm_timed_pages_target <= 0 \|\| cmm_timeout_seconds <= 0) {
	191	if (timer_pending(&cmm_timer))
	192	del_timer(&cmm_timer);
	193	return;
	194	}
	195	if (timer_pending(&cmm_timer)) {
	196	if (mod_timer(&cmm_timer, jiffies + cmm_timeout_seconds*HZ))
	197	return;
	198	}
	199	cmm_timer.function = cmm_timer_fn;
	200	cmm_timer.data = 0;
	201	cmm_timer.expires = jiffies + cmm_timeout_seconds*HZ;
	202	add_timer(&cmm_timer);
	203	}
	204
	205	static void
	206	cmm_timer_fn(unsigned long ignored)
	207	{
8bc719d3	208	long nr;
1da177e4	209
8bc719d3 MS	210	nr = cmm_timed_pages_target - cmm_timeout_pages;
8bc719d3 MS	211	if (nr < 0)
1da177e4 LT	212	cmm_timed_pages_target = 0;
1da177e4 LT	213	else
8bc719d3	214	cmm_timed_pages_target = nr;
1da177e4 LT	215	cmm_kick_thread();
	216	cmm_set_timer();
	217	}
	218
	219	void
8bc719d3	220	cmm_set_pages(long nr)
1da177e4	221	{
8bc719d3	222	cmm_pages_target = nr;
1da177e4 LT	223	cmm_kick_thread();
	224	}
	225
	226	long
	227	cmm_get_pages(void)
	228	{
	229	return cmm_pages;
	230	}
	231
	232	void
8bc719d3	233	cmm_add_timed_pages(long nr)
1da177e4	234	{
8bc719d3	235	cmm_timed_pages_target += nr;
1da177e4 LT	236	cmm_kick_thread();
	237	}
	238
	239	long
	240	cmm_get_timed_pages(void)
	241	{
	242	return cmm_timed_pages;
	243	}
	244
	245	void
8bc719d3	246	cmm_set_timeout(long nr, long seconds)
1da177e4	247	{
8bc719d3	248	cmm_timeout_pages = nr;
1da177e4 LT	249	cmm_timeout_seconds = seconds;
	250	cmm_set_timer();
	251	}
	252
4d284cac	253	static int
1da177e4 LT	254	cmm_skip_blanks(char cp, char *endp)
	255	{
	256	char *str;
	257
	258	for (str = cp; str == ' ' \|\| str == '\t'; str++);
	259	*endp = str;
	260	return str != cp;
	261	}
	262
	263	#ifdef CONFIG_CMM_PROC
1da177e4 LT	264
	265	static struct ctl_table cmm_table[];
	266
	267	static int
8d65af78	268	cmm_pages_handler(ctl_table *ctl, int write,
aaedd944	269	void __user buffer, size_t lenp, loff_t *ppos)
1da177e4 LT	270	{
1da177e4 LT	271	char buf[16], *p;
8bc719d3	272	long nr;
1da177e4 LT	273	int len;
	274
	275	if (!lenp \|\| (ppos && !write)) {
	276	*lenp = 0;
	277	return 0;
	278	}
	279
	280	if (write) {
	281	len = *lenp;
	282	if (copy_from_user(buf, buffer,
	283	len > sizeof(buf) ? sizeof(buf) : len))
	284	return -EFAULT;
	285	buf[sizeof(buf) - 1] = '\0';
	286	cmm_skip_blanks(buf, &p);
8bc719d3	287	nr = simple_strtoul(p, &p, 0);
1da177e4	288	if (ctl == &cmm_table[0])
8bc719d3	289	cmm_set_pages(nr);
1da177e4	290	else
8bc719d3	291	cmm_add_timed_pages(nr);
1da177e4 LT	292	} else {
1da177e4 LT	293	if (ctl == &cmm_table[0])
8bc719d3	294	nr = cmm_get_pages();
1da177e4	295	else
8bc719d3 MS	296	nr = cmm_get_timed_pages();
8bc719d3 MS	297	len = sprintf(buf, "%ld\n", nr);
1da177e4 LT	298	if (len > *lenp)
	299	len = *lenp;
	300	if (copy_to_user(buffer, buf, len))
	301	return -EFAULT;
	302	}
	303	*lenp = len;
	304	*ppos += len;
	305	return 0;
	306	}
	307
	308	static int
8d65af78	309	cmm_timeout_handler(ctl_table *ctl, int write,
aaedd944	310	void __user buffer, size_t lenp, loff_t *ppos)
1da177e4 LT	311	{
1da177e4 LT	312	char buf[64], *p;
8bc719d3	313	long nr, seconds;
1da177e4 LT	314	int len;
	315
	316	if (!lenp \|\| (ppos && !write)) {
	317	*lenp = 0;
	318	return 0;
	319	}
	320
	321	if (write) {
	322	len = *lenp;
	323	if (copy_from_user(buf, buffer,
	324	len > sizeof(buf) ? sizeof(buf) : len))
	325	return -EFAULT;
	326	buf[sizeof(buf) - 1] = '\0';
	327	cmm_skip_blanks(buf, &p);
8bc719d3	328	nr = simple_strtoul(p, &p, 0);
1da177e4	329	cmm_skip_blanks(p, &p);
7d5d688f	330	seconds = simple_strtoul(p, &p, 0);
8bc719d3	331	cmm_set_timeout(nr, seconds);
1da177e4 LT	332	} else {
	333	len = sprintf(buf, "%ld %ld\n",
	334	cmm_timeout_pages, cmm_timeout_seconds);
	335	if (len > *lenp)
	336	len = *lenp;
	337	if (copy_to_user(buffer, buf, len))
	338	return -EFAULT;
	339	}
	340	*lenp = len;
	341	*ppos += len;
	342	return 0;
	343	}
	344
	345	static struct ctl_table cmm_table[] = {
	346	{
1da177e4	347	.procname = "cmm_pages",
5e8b1c40	348	.mode = 0644,
6d456111	349	.proc_handler = cmm_pages_handler,
1da177e4 LT	350	},
1da177e4 LT	351	{
1da177e4	352	.procname = "cmm_timed_pages",
5e8b1c40	353	.mode = 0644,
6d456111	354	.proc_handler = cmm_pages_handler,
1da177e4 LT	355	},
1da177e4 LT	356	{
1da177e4	357	.procname = "cmm_timeout",
5e8b1c40	358	.mode = 0644,
6d456111	359	.proc_handler = cmm_timeout_handler,
1da177e4	360	},
b05fd35d	361	{ }
1da177e4 LT	362	};
	363
	364	static struct ctl_table cmm_dir_table[] = {
	365	{
1da177e4 LT	366	.procname = "vm",
	367	.maxlen = 0,
	368	.mode = 0555,
	369	.child = cmm_table,
	370	},
b05fd35d	371	{ }
1da177e4 LT	372	};
	373	#endif
	374
	375	#ifdef CONFIG_CMM_IUCV
	376	#define SMSG_PREFIX "CMM"
	377	static void
09003ed9	378	cmm_smsg_target(const char from, char msg)
1da177e4	379	{
8bc719d3	380	long nr, seconds;
1da177e4	381
15439d74 MS	382	if (strlen(sender) > 0 && strcmp(from, sender) != 0)
15439d74 MS	383	return;
1da177e4 LT	384	if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg))
	385	return;
	386	if (strncmp(msg, "SHRINK", 6) == 0) {
	387	if (!cmm_skip_blanks(msg + 6, &msg))
	388	return;
8bc719d3	389	nr = simple_strtoul(msg, &msg, 0);
1da177e4 LT	390	cmm_skip_blanks(msg, &msg);
1da177e4 LT	391	if (*msg == '\0')
8bc719d3	392	cmm_set_pages(nr);
1da177e4 LT	393	} else if (strncmp(msg, "RELEASE", 7) == 0) {
	394	if (!cmm_skip_blanks(msg + 7, &msg))
	395	return;
8bc719d3	396	nr = simple_strtoul(msg, &msg, 0);
1da177e4 LT	397	cmm_skip_blanks(msg, &msg);
1da177e4 LT	398	if (*msg == '\0')
8bc719d3	399	cmm_add_timed_pages(nr);
1da177e4 LT	400	} else if (strncmp(msg, "REUSE", 5) == 0) {
	401	if (!cmm_skip_blanks(msg + 5, &msg))
	402	return;
8bc719d3	403	nr = simple_strtoul(msg, &msg, 0);
1da177e4 LT	404	if (!cmm_skip_blanks(msg, &msg))
1da177e4 LT	405	return;
7d5d688f	406	seconds = simple_strtoul(msg, &msg, 0);
1da177e4 LT	407	cmm_skip_blanks(msg, &msg);
1da177e4 LT	408	if (*msg == '\0')
8bc719d3	409	cmm_set_timeout(nr, seconds);
1da177e4 LT	410	}
	411	}
	412	#endif
	413
2b67fc46	414	static struct ctl_table_header *cmm_sysctl_header;
1da177e4	415
52b169c8 MS	416	static int cmm_suspend(void)
	417	{
	418	cmm_suspended = 1;
	419	cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list);
	420	cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list);
	421	return 0;
	422	}
	423
	424	static int cmm_resume(void)
	425	{
	426	cmm_suspended = 0;
	427	cmm_kick_thread();
	428	return 0;
	429	}
	430
	431	static int cmm_power_event(struct notifier_block *this,
	432	unsigned long event, void *ptr)
	433	{
	434	switch (event) {
	435	case PM_POST_HIBERNATION:
	436	return cmm_resume();
	437	case PM_HIBERNATION_PREPARE:
	438	return cmm_suspend();
	439	default:
	440	return NOTIFY_DONE;
	441	}
	442	}
	443
	444	static struct notifier_block cmm_power_notifier = {
	445	.notifier_call = cmm_power_event,
	446	};
	447
1da177e4 LT	448	static int
	449	cmm_init (void)
	450	{
e8216dee HC	451	int rc = -ENOMEM;
e8216dee HC	452
1da177e4	453	#ifdef CONFIG_CMM_PROC
0b4d4147	454	cmm_sysctl_header = register_sysctl_table(cmm_dir_table);
e8216dee	455	if (!cmm_sysctl_header)
52b169c8	456	goto out_sysctl;
1da177e4 LT	457	#endif
1da177e4 LT	458	#ifdef CONFIG_CMM_IUCV
e8216dee HC	459	rc = smsg_register_callback(SMSG_PREFIX, cmm_smsg_target);
	460	if (rc < 0)
	461	goto out_smsg;
1da177e4	462	#endif
e8216dee HC	463	rc = register_oom_notifier(&cmm_oom_nb);
	464	if (rc < 0)
	465	goto out_oom_notify;
52b169c8 MS	466	rc = register_pm_notifier(&cmm_power_notifier);
	467	if (rc)
	468	goto out_pm;
1da177e4 LT	469	init_waitqueue_head(&cmm_thread_wait);
1da177e4 LT	470	init_timer(&cmm_timer);
e8216dee HC	471	cmm_thread_ptr = kthread_run(cmm_thread, NULL, "cmmthread");
e8216dee HC	472	rc = IS_ERR(cmm_thread_ptr) ? PTR_ERR(cmm_thread_ptr) : 0;
52b169c8 MS	473	if (rc)
	474	goto out_kthread;
	475	return 0;
e8216dee	476
52b169c8 MS	477	out_kthread:
	478	unregister_pm_notifier(&cmm_power_notifier);
	479	out_pm:
	480	unregister_oom_notifier(&cmm_oom_nb);
e8216dee HC	481	out_oom_notify:
	482	#ifdef CONFIG_CMM_IUCV
	483	smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
	484	out_smsg:
	485	#endif
	486	#ifdef CONFIG_CMM_PROC
	487	unregister_sysctl_table(cmm_sysctl_header);
52b169c8	488	out_sysctl:
e8216dee	489	#endif
e8216dee	490	return rc;
1da177e4 LT	491	}
	492
	493	static void
	494	cmm_exit(void)
	495	{
e8216dee	496	kthread_stop(cmm_thread_ptr);
52b169c8	497	unregister_pm_notifier(&cmm_power_notifier);
8bc719d3	498	unregister_oom_notifier(&cmm_oom_nb);
1da177e4 LT	499	cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list);
	500	cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list);
	501	#ifdef CONFIG_CMM_PROC
	502	unregister_sysctl_table(cmm_sysctl_header);
	503	#endif
	504	#ifdef CONFIG_CMM_IUCV
	505	smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
	506	#endif
	507	}
	508
	509	module_init(cmm_init);
	510	module_exit(cmm_exit);
	511
	512	EXPORT_SYMBOL(cmm_set_pages);
	513	EXPORT_SYMBOL(cmm_get_pages);
	514	EXPORT_SYMBOL(cmm_add_timed_pages);
	515	EXPORT_SYMBOL(cmm_get_timed_pages);
	516	EXPORT_SYMBOL(cmm_set_timeout);
	517
	518	MODULE_LICENSE("GPL");