[linux-block.git] / arch / s390 / kernel / lgr.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Linux Guest Relocation (LGR) detection
 *
 * Copyright IBM Corp. 2012
 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
 */

#include <linux/init.h>
#include <linux/export.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <asm/facility.h>
#include <asm/sysinfo.h>
#include <asm/ebcdic.h>
#include <asm/debug.h>
#include <asm/ipl.h>

#define LGR_TIMER_INTERVAL_SECS (30 * 60)
#define VM_LEVEL_MAX 2 /* Maximum is 8, but we only record two levels */

/*
 * LGR info: Contains stfle and stsi data
 */
struct lgr_info {
	/* Bit field with facility information: 4 DWORDs are stored */
	u64 stfle_fac_list[4];
	/* Level of system (1 = CEC, 2 = LPAR, 3 = z/VM */
	u32 level;
	/* Level 1: CEC info (stsi 1.1.1) */
	char manufacturer[16];
	char type[4];
	char sequence[16];
	char plant[4];
	char model[16];
	/* Level 2: LPAR info (stsi 2.2.2) */
	u16 lpar_number;
	char name[8];
	/* Level 3: VM info (stsi 3.2.2) */
	u8 vm_count;
	struct {
		char name[8];
		char cpi[16];
	} vm[VM_LEVEL_MAX];
} __packed __aligned(8);

/*
 * LGR globals
 */
static char lgr_page[PAGE_SIZE] __aligned(PAGE_SIZE);
static struct lgr_info lgr_info_last;
static struct lgr_info lgr_info_cur;
static struct debug_info *lgr_dbf;

/*
 * Copy buffer and then convert it to ASCII
 */
static void cpascii(char *dst, char *src, int size)
{
	memcpy(dst, src, size);
	EBCASC(dst, size);
}

/*
 * Fill LGR info with 1.1.1 stsi data
 */
static void lgr_stsi_1_1_1(struct lgr_info *lgr_info)
{
	struct sysinfo_1_1_1 *si = (void *) lgr_page;

	if (stsi(si, 1, 1, 1))
		return;
	cpascii(lgr_info->manufacturer, si->manufacturer,
		sizeof(si->manufacturer));
	cpascii(lgr_info->type, si->type, sizeof(si->type));
	cpascii(lgr_info->model, si->model, sizeof(si->model));
	cpascii(lgr_info->sequence, si->sequence, sizeof(si->sequence));
	cpascii(lgr_info->plant, si->plant, sizeof(si->plant));
}

/*
 * Fill LGR info with 2.2.2 stsi data
 */
static void lgr_stsi_2_2_2(struct lgr_info *lgr_info)
{
	struct sysinfo_2_2_2 *si = (void *) lgr_page;

	if (stsi(si, 2, 2, 2))
		return;
	cpascii(lgr_info->name, si->name, sizeof(si->name));
	lgr_info->lpar_number = si->lpar_number;
}

/*
 * Fill LGR info with 3.2.2 stsi data
 */
static void lgr_stsi_3_2_2(struct lgr_info *lgr_info)
{
	struct sysinfo_3_2_2 *si = (void *) lgr_page;
	int i;

	if (stsi(si, 3, 2, 2))
		return;
	for (i = 0; i < min_t(u8, si->count, VM_LEVEL_MAX); i++) {
		cpascii(lgr_info->vm[i].name, si->vm[i].name,
			sizeof(si->vm[i].name));
		cpascii(lgr_info->vm[i].cpi, si->vm[i].cpi,
			sizeof(si->vm[i].cpi));
	}
	lgr_info->vm_count = si->count;
}

/*
 * Fill LGR info with current data
 */
static void lgr_info_get(struct lgr_info *lgr_info)
{
	int level;

	memset(lgr_info, 0, sizeof(*lgr_info));
	stfle(lgr_info->stfle_fac_list, ARRAY_SIZE(lgr_info->stfle_fac_list));
	level = stsi(NULL, 0, 0, 0);
	lgr_info->level = level;
	if (level >= 1)
		lgr_stsi_1_1_1(lgr_info);
	if (level >= 2)
		lgr_stsi_2_2_2(lgr_info);
	if (level >= 3)
		lgr_stsi_3_2_2(lgr_info);
}

/*
 * Check if LGR info has changed and if yes log new LGR info to s390dbf
 */
void lgr_info_log(void)
{
	static DEFINE_SPINLOCK(lgr_info_lock);
	unsigned long flags;

	if (!spin_trylock_irqsave(&lgr_info_lock, flags))
		return;
	lgr_info_get(&lgr_info_cur);
	if (memcmp(&lgr_info_last, &lgr_info_cur, sizeof(lgr_info_cur)) != 0) {
		debug_event(lgr_dbf, 1, &lgr_info_cur, sizeof(lgr_info_cur));
		lgr_info_last = lgr_info_cur;
	}
	spin_unlock_irqrestore(&lgr_info_lock, flags);
}
EXPORT_SYMBOL_GPL(lgr_info_log);

static void lgr_timer_set(void);

/*
 * LGR timer callback
 */
static void lgr_timer_fn(struct timer_list *unused)
{
	lgr_info_log();
	lgr_timer_set();
}

static struct timer_list lgr_timer;

/*
 * Setup next LGR timer
 */
static void lgr_timer_set(void)
{
	mod_timer(&lgr_timer, jiffies + msecs_to_jiffies(LGR_TIMER_INTERVAL_SECS * MSEC_PER_SEC));
}

/*
 * Initialize LGR: Add s390dbf, write initial lgr_info and setup timer
 */
static int __init lgr_init(void)
{
	lgr_dbf = debug_register("lgr", 1, 1, sizeof(struct lgr_info));
	if (!lgr_dbf)
		return -ENOMEM;
	debug_register_view(lgr_dbf, &debug_hex_ascii_view);
	lgr_info_get(&lgr_info_last);
	debug_event(lgr_dbf, 1, &lgr_info_last, sizeof(lgr_info_last));
	timer_setup(&lgr_timer, lgr_timer_fn, TIMER_DEFERRABLE);
	lgr_timer_set();
	return 0;
}
device_initcall(lgr_init);
Commit	Line	Data
a17ae4c3	1	// SPDX-License-Identifier: GPL-2.0
3ab121ab MH	2	/*
	3	* Linux Guest Relocation (LGR) detection
	4	*
	5	* Copyright IBM Corp. 2012
	6	* Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
	7	*/
	8
8ba8b05f PG	9	#include <linux/init.h>
8ba8b05f PG	10	#include <linux/export.h>
3ab121ab MH	11	#include <linux/timer.h>
3ab121ab MH	12	#include <linux/slab.h>
1e3cab2f	13	#include <asm/facility.h>
3ab121ab MH	14	#include <asm/sysinfo.h>
3ab121ab MH	15	#include <asm/ebcdic.h>
3ab121ab MH	16	#include <asm/debug.h>
	17	#include <asm/ipl.h>
	18
	19	#define LGR_TIMER_INTERVAL_SECS (30 * 60)
	20	#define VM_LEVEL_MAX 2 /* Maximum is 8, but we only record two levels */
	21
	22	/*
	23	* LGR info: Contains stfle and stsi data
	24	*/
	25	struct lgr_info {
	26	/* Bit field with facility information: 4 DWORDs are stored */
	27	u64 stfle_fac_list[4];
	28	/* Level of system (1 = CEC, 2 = LPAR, 3 = z/VM */
	29	u32 level;
	30	/* Level 1: CEC info (stsi 1.1.1) */
	31	char manufacturer[16];
	32	char type[4];
	33	char sequence[16];
	34	char plant[4];
	35	char model[16];
	36	/* Level 2: LPAR info (stsi 2.2.2) */
	37	u16 lpar_number;
	38	char name[8];
	39	/* Level 3: VM info (stsi 3.2.2) */
	40	u8 vm_count;
	41	struct {
	42	char name[8];
	43	char cpi[16];
	44	} vm[VM_LEVEL_MAX];
	45	} __packed __aligned(8);
	46
	47	/*
	48	* LGR globals
	49	*/
2b754757	50	static char lgr_page[PAGE_SIZE] __aligned(PAGE_SIZE);
3ab121ab MH	51	static struct lgr_info lgr_info_last;
	52	static struct lgr_info lgr_info_cur;
	53	static struct debug_info *lgr_dbf;
	54
3ab121ab MH	55	/*
	56	* Copy buffer and then convert it to ASCII
	57	*/
	58	static void cpascii(char dst, char src, int size)
	59	{
	60	memcpy(dst, src, size);
	61	EBCASC(dst, size);
	62	}
	63
	64	/*
	65	* Fill LGR info with 1.1.1 stsi data
	66	*/
	67	static void lgr_stsi_1_1_1(struct lgr_info *lgr_info)
	68	{
2b754757	69	struct sysinfo_1_1_1 si = (void ) lgr_page;
3ab121ab	70
caf757c6	71	if (stsi(si, 1, 1, 1))
3ab121ab MH	72	return;
	73	cpascii(lgr_info->manufacturer, si->manufacturer,
	74	sizeof(si->manufacturer));
	75	cpascii(lgr_info->type, si->type, sizeof(si->type));
	76	cpascii(lgr_info->model, si->model, sizeof(si->model));
	77	cpascii(lgr_info->sequence, si->sequence, sizeof(si->sequence));
	78	cpascii(lgr_info->plant, si->plant, sizeof(si->plant));
	79	}
	80
	81	/*
	82	* Fill LGR info with 2.2.2 stsi data
	83	*/
	84	static void lgr_stsi_2_2_2(struct lgr_info *lgr_info)
	85	{
2b754757	86	struct sysinfo_2_2_2 si = (void ) lgr_page;
3ab121ab	87
caf757c6	88	if (stsi(si, 2, 2, 2))
3ab121ab MH	89	return;
3ab121ab MH	90	cpascii(lgr_info->name, si->name, sizeof(si->name));
ba2d394c	91	lgr_info->lpar_number = si->lpar_number;
3ab121ab MH	92	}
	93
	94	/*
	95	* Fill LGR info with 3.2.2 stsi data
	96	*/
	97	static void lgr_stsi_3_2_2(struct lgr_info *lgr_info)
	98	{
2b754757	99	struct sysinfo_3_2_2 si = (void ) lgr_page;
3ab121ab MH	100	int i;
3ab121ab MH	101
caf757c6	102	if (stsi(si, 3, 2, 2))
3ab121ab MH	103	return;
	104	for (i = 0; i < min_t(u8, si->count, VM_LEVEL_MAX); i++) {
	105	cpascii(lgr_info->vm[i].name, si->vm[i].name,
	106	sizeof(si->vm[i].name));
	107	cpascii(lgr_info->vm[i].cpi, si->vm[i].cpi,
	108	sizeof(si->vm[i].cpi));
	109	}
	110	lgr_info->vm_count = si->count;
	111	}
	112
	113	/*
	114	* Fill LGR info with current data
	115	*/
	116	static void lgr_info_get(struct lgr_info *lgr_info)
	117	{
caf757c6 HC	118	int level;
caf757c6 HC	119
3ab121ab MH	120	memset(lgr_info, 0, sizeof(*lgr_info));
3ab121ab MH	121	stfle(lgr_info->stfle_fac_list, ARRAY_SIZE(lgr_info->stfle_fac_list));
caf757c6 HC	122	level = stsi(NULL, 0, 0, 0);
	123	lgr_info->level = level;
	124	if (level >= 1)
3ab121ab	125	lgr_stsi_1_1_1(lgr_info);
caf757c6	126	if (level >= 2)
3ab121ab	127	lgr_stsi_2_2_2(lgr_info);
caf757c6	128	if (level >= 3)
3ab121ab MH	129	lgr_stsi_3_2_2(lgr_info);
	130	}
	131
	132	/*
	133	* Check if LGR info has changed and if yes log new LGR info to s390dbf
	134	*/
	135	void lgr_info_log(void)
	136	{
	137	static DEFINE_SPINLOCK(lgr_info_lock);
	138	unsigned long flags;
	139
	140	if (!spin_trylock_irqsave(&lgr_info_lock, flags))
	141	return;
	142	lgr_info_get(&lgr_info_cur);
	143	if (memcmp(&lgr_info_last, &lgr_info_cur, sizeof(lgr_info_cur)) != 0) {
	144	debug_event(lgr_dbf, 1, &lgr_info_cur, sizeof(lgr_info_cur));
	145	lgr_info_last = lgr_info_cur;
	146	}
	147	spin_unlock_irqrestore(&lgr_info_lock, flags);
	148	}
	149	EXPORT_SYMBOL_GPL(lgr_info_log);
	150
	151	static void lgr_timer_set(void);
	152
	153	/*
	154	* LGR timer callback
	155	*/
5cd79d6a	156	static void lgr_timer_fn(struct timer_list *unused)
3ab121ab MH	157	{
	158	lgr_info_log();
	159	lgr_timer_set();
	160	}
	161
5cd79d6a	162	static struct timer_list lgr_timer;
3ab121ab MH	163
	164	/*
	165	* Setup next LGR timer
	166	*/
	167	static void lgr_timer_set(void)
	168	{
0188d08a	169	mod_timer(&lgr_timer, jiffies + msecs_to_jiffies(LGR_TIMER_INTERVAL_SECS * MSEC_PER_SEC));
3ab121ab MH	170	}
	171
	172	/*
	173	* Initialize LGR: Add s390dbf, write initial lgr_info and setup timer
	174	*/
	175	static int __init lgr_init(void)
	176	{
3ab121ab	177	lgr_dbf = debug_register("lgr", 1, 1, sizeof(struct lgr_info));
2b754757	178	if (!lgr_dbf)
3ab121ab	179	return -ENOMEM;
3ab121ab MH	180	debug_register_view(lgr_dbf, &debug_hex_ascii_view);
	181	lgr_info_get(&lgr_info_last);
	182	debug_event(lgr_dbf, 1, &lgr_info_last, sizeof(lgr_info_last));
5cd79d6a	183	timer_setup(&lgr_timer, lgr_timer_fn, TIMER_DEFERRABLE);
3ab121ab MH	184	lgr_timer_set();
	185	return 0;
	186	}
8ba8b05f	187	device_initcall(lgr_init);