[linux-block.git] / arch / powerpc / kernel / rtasd.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
 *
 * Communication to userspace based on kernel/printk.c
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/vmalloc.h>
#include <linux/spinlock.h>
#include <linux/cpu.h>
#include <linux/workqueue.h>
#include <linux/slab.h>
#include <linux/topology.h>

#include <linux/uaccess.h>
#include <asm/io.h>
#include <asm/rtas.h>
#include <asm/nvram.h>
#include <linux/atomic.h>
#include <asm/machdep.h>
#include <asm/topology.h>


static DEFINE_SPINLOCK(rtasd_log_lock);

static DECLARE_WAIT_QUEUE_HEAD(rtas_log_wait);

static char *rtas_log_buf;
static unsigned long rtas_log_start;
static unsigned long rtas_log_size;

static int surveillance_timeout = -1;

static unsigned int rtas_error_log_max;
static unsigned int rtas_error_log_buffer_max;

/* RTAS service tokens */
static unsigned int event_scan;
static unsigned int rtas_event_scan_rate;

static bool full_rtas_msgs;

/* Stop logging to nvram after first fatal error */
static int logging_enabled; /* Until we initialize everything,
                             * make sure we don't try logging
                             * anything */
static int error_log_cnt;

/*
 * Since we use 32 bit RTAS, the physical address of this must be below
 * 4G or else bad things happen. Allocate this in the kernel data and
 * make it big enough.
 */
static unsigned char logdata[RTAS_ERROR_LOG_MAX];

static char *rtas_type[] = {
	"Unknown", "Retry", "TCE Error", "Internal Device Failure",
	"Timeout", "Data Parity", "Address Parity", "Cache Parity",
	"Address Invalid", "ECC Uncorrected", "ECC Corrupted",
};

static char *rtas_event_type(int type)
{
	if ((type > 0) && (type < 11))
		return rtas_type[type];

	switch (type) {
		case RTAS_TYPE_EPOW:
			return "EPOW";
		case RTAS_TYPE_PLATFORM:
			return "Platform Error";
		case RTAS_TYPE_IO:
			return "I/O Event";
		case RTAS_TYPE_INFO:
			return "Platform Information Event";
		case RTAS_TYPE_DEALLOC:
			return "Resource Deallocation Event";
		case RTAS_TYPE_DUMP:
			return "Dump Notification Event";
		case RTAS_TYPE_PRRN:
			return "Platform Resource Reassignment Event";
		case RTAS_TYPE_HOTPLUG:
			return "Hotplug Event";
	}

	return rtas_type[0];
}

/* To see this info, grep RTAS /var/log/messages and each entry
 * will be collected together with obvious begin/end.
 * There will be a unique identifier on the begin and end lines.
 * This will persist across reboots.
 *
 * format of error logs returned from RTAS:
 * bytes	(size)	: contents
 * --------------------------------------------------------
 * 0-7		(8)	: rtas_error_log
 * 8-47		(40)	: extended info
 * 48-51	(4)	: vendor id
 * 52-1023 (vendor specific) : location code and debug data
 */
static void printk_log_rtas(char *buf, int len)
{

	int i,j,n = 0;
	int perline = 16;
	char buffer[64];
	char * str = "RTAS event";

	if (full_rtas_msgs) {
		printk(RTAS_DEBUG "%d -------- %s begin --------\n",
		       error_log_cnt, str);

		/*
		 * Print perline bytes on each line, each line will start
		 * with RTAS and a changing number, so syslogd will
		 * print lines that are otherwise the same.  Separate every
		 * 4 bytes with a space.
		 */
		for (i = 0; i < len; i++) {
			j = i % perline;
			if (j == 0) {
				memset(buffer, 0, sizeof(buffer));
				n = sprintf(buffer, "RTAS %d:", i/perline);
			}

			if ((i % 4) == 0)
				n += sprintf(buffer+n, " ");

			n += sprintf(buffer+n, "%02x", (unsigned char)buf[i]);

			if (j == (perline-1))
				printk(KERN_DEBUG "%s\n", buffer);
		}
		if ((i % perline) != 0)
			printk(KERN_DEBUG "%s\n", buffer);

		printk(RTAS_DEBUG "%d -------- %s end ----------\n",
		       error_log_cnt, str);
	} else {
		struct rtas_error_log *errlog = (struct rtas_error_log *)buf;

		printk(RTAS_DEBUG "event: %d, Type: %s (%d), Severity: %d\n",
		       error_log_cnt,
		       rtas_event_type(rtas_error_type(errlog)),
		       rtas_error_type(errlog),
		       rtas_error_severity(errlog));
	}
}

static int log_rtas_len(char * buf)
{
	int len;
	struct rtas_error_log *err;
	uint32_t extended_log_length;

	/* rtas fixed header */
	len = 8;
	err = (struct rtas_error_log *)buf;
	extended_log_length = rtas_error_extended_log_length(err);
	if (rtas_error_extended(err) && extended_log_length) {

		/* extended header */
		len += extended_log_length;
	}

	if (rtas_error_log_max == 0)
		rtas_error_log_max = rtas_get_error_log_max();

	if (len > rtas_error_log_max)
		len = rtas_error_log_max;

	return len;
}

/*
 * First write to nvram, if fatal error, that is the only
 * place we log the info.  The error will be picked up
 * on the next reboot by rtasd.  If not fatal, run the
 * method for the type of error.  Currently, only RTAS
 * errors have methods implemented, but in the future
 * there might be a need to store data in nvram before a
 * call to panic().
 *
 * XXX We write to nvram periodically, to indicate error has
 * been written and sync'd, but there is a possibility
 * that if we don't shutdown correctly, a duplicate error
 * record will be created on next reboot.
 */
void pSeries_log_error(char *buf, unsigned int err_type, int fatal)
{
	unsigned long offset;
	unsigned long s;
	int len = 0;

	pr_debug("rtasd: logging event\n");
	if (buf == NULL)
		return;

	spin_lock_irqsave(&rtasd_log_lock, s);

	/* get length and increase count */
	switch (err_type & ERR_TYPE_MASK) {
	case ERR_TYPE_RTAS_LOG:
		len = log_rtas_len(buf);
		if (!(err_type & ERR_FLAG_BOOT))
			error_log_cnt++;
		break;
	case ERR_TYPE_KERNEL_PANIC:
	default:
		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
		spin_unlock_irqrestore(&rtasd_log_lock, s);
		return;
	}

#ifdef CONFIG_PPC64
	/* Write error to NVRAM */
	if (logging_enabled && !(err_type & ERR_FLAG_BOOT))
		nvram_write_error_log(buf, len, err_type, error_log_cnt);
#endif /* CONFIG_PPC64 */

	/*
	 * rtas errors can occur during boot, and we do want to capture
	 * those somewhere, even if nvram isn't ready (why not?), and even
	 * if rtasd isn't ready. Put them into the boot log, at least.
	 */
	if ((err_type & ERR_TYPE_MASK) == ERR_TYPE_RTAS_LOG)
		printk_log_rtas(buf, len);

	/* Check to see if we need to or have stopped logging */
	if (fatal || !logging_enabled) {
		logging_enabled = 0;
		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
		spin_unlock_irqrestore(&rtasd_log_lock, s);
		return;
	}

	/* call type specific method for error */
	switch (err_type & ERR_TYPE_MASK) {
	case ERR_TYPE_RTAS_LOG:
		offset = rtas_error_log_buffer_max *
			((rtas_log_start+rtas_log_size) & LOG_NUMBER_MASK);

		/* First copy over sequence number */
		memcpy(&rtas_log_buf[offset], (void *) &error_log_cnt, sizeof(int));

		/* Second copy over error log data */
		offset += sizeof(int);
		memcpy(&rtas_log_buf[offset], buf, len);

		if (rtas_log_size < LOG_NUMBER)
			rtas_log_size += 1;
		else
			rtas_log_start += 1;

		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
		spin_unlock_irqrestore(&rtasd_log_lock, s);
		wake_up_interruptible(&rtas_log_wait);
		break;
	case ERR_TYPE_KERNEL_PANIC:
	default:
		WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
		spin_unlock_irqrestore(&rtasd_log_lock, s);
		return;
	}
}

static void handle_rtas_event(const struct rtas_error_log *log)
{
	if (!machine_is(pseries))
		return;

	if (rtas_error_type(log) == RTAS_TYPE_PRRN)
		pr_info_ratelimited("Platform resource reassignment ignored.\n");
}

static int rtas_log_open(struct inode * inode, struct file * file)
{
	return 0;
}

static int rtas_log_release(struct inode * inode, struct file * file)
{
	return 0;
}

/* This will check if all events are logged, if they are then, we
 * know that we can safely clear the events in NVRAM.
 * Next we'll sit and wait for something else to log.
 */
static ssize_t rtas_log_read(struct file * file, char __user * buf,
			 size_t count, loff_t *ppos)
{
	int error;
	char *tmp;
	unsigned long s;
	unsigned long offset;

	if (!buf || count < rtas_error_log_buffer_max)
		return -EINVAL;

	count = rtas_error_log_buffer_max;

	if (!access_ok(buf, count))
		return -EFAULT;

	tmp = kmalloc(count, GFP_KERNEL);
	if (!tmp)
		return -ENOMEM;

	spin_lock_irqsave(&rtasd_log_lock, s);

	/* if it's 0, then we know we got the last one (the one in NVRAM) */
	while (rtas_log_size == 0) {
		if (file->f_flags & O_NONBLOCK) {
			spin_unlock_irqrestore(&rtasd_log_lock, s);
			error = -EAGAIN;
			goto out;
		}

		if (!logging_enabled) {
			spin_unlock_irqrestore(&rtasd_log_lock, s);
			error = -ENODATA;
			goto out;
		}
#ifdef CONFIG_PPC64
		nvram_clear_error_log();
#endif /* CONFIG_PPC64 */

		spin_unlock_irqrestore(&rtasd_log_lock, s);
		error = wait_event_interruptible(rtas_log_wait, rtas_log_size);
		if (error)
			goto out;
		spin_lock_irqsave(&rtasd_log_lock, s);
	}

	offset = rtas_error_log_buffer_max * (rtas_log_start & LOG_NUMBER_MASK);
	memcpy(tmp, &rtas_log_buf[offset], count);

	rtas_log_start += 1;
	rtas_log_size -= 1;
	spin_unlock_irqrestore(&rtasd_log_lock, s);

	error = copy_to_user(buf, tmp, count) ? -EFAULT : count;
out:
	kfree(tmp);
	return error;
}

static __poll_t rtas_log_poll(struct file *file, poll_table * wait)
{
	poll_wait(file, &rtas_log_wait, wait);
	if (rtas_log_size)
		return EPOLLIN | EPOLLRDNORM;
	return 0;
}

static const struct proc_ops rtas_log_proc_ops = {
	.proc_read	= rtas_log_read,
	.proc_poll	= rtas_log_poll,
	.proc_open	= rtas_log_open,
	.proc_release	= rtas_log_release,
	.proc_lseek	= noop_llseek,
};

static int enable_surveillance(int timeout)
{
	int error;

	error = rtas_set_indicator(SURVEILLANCE_TOKEN, 0, timeout);

	if (error == 0)
		return 0;

	if (error == -EINVAL) {
		printk(KERN_DEBUG "rtasd: surveillance not supported\n");
		return 0;
	}

	printk(KERN_ERR "rtasd: could not update surveillance\n");
	return -1;
}

static void do_event_scan(void)
{
	int error;
	do {
		memset(logdata, 0, rtas_error_log_max);
		error = rtas_call(event_scan, 4, 1, NULL,
				  RTAS_EVENT_SCAN_ALL_EVENTS, 0,
				  __pa(logdata), rtas_error_log_max);
		if (error == -1) {
			printk(KERN_ERR "event-scan failed\n");
			break;
		}

		if (error == 0) {
			if (rtas_error_type((struct rtas_error_log *)logdata) !=
			    RTAS_TYPE_PRRN)
				pSeries_log_error(logdata, ERR_TYPE_RTAS_LOG,
						  0);
			handle_rtas_event((struct rtas_error_log *)logdata);
		}

	} while(error == 0);
}

static void rtas_event_scan(struct work_struct *w);
static DECLARE_DELAYED_WORK(event_scan_work, rtas_event_scan);

/*
 * Delay should be at least one second since some machines have problems if
 * we call event-scan too quickly.
 */
static unsigned long event_scan_delay = 1*HZ;
static int first_pass = 1;

static void rtas_event_scan(struct work_struct *w)
{
	unsigned int cpu;

	do_event_scan();

	cpus_read_lock();

	/* raw_ OK because just using CPU as starting point. */
	cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
        if (cpu >= nr_cpu_ids) {
		cpu = cpumask_first(cpu_online_mask);

		if (first_pass) {
			first_pass = 0;
			event_scan_delay = 30*HZ/rtas_event_scan_rate;

			if (surveillance_timeout != -1) {
				pr_debug("rtasd: enabling surveillance\n");
				enable_surveillance(surveillance_timeout);
				pr_debug("rtasd: surveillance enabled\n");
			}
		}
	}

	schedule_delayed_work_on(cpu, &event_scan_work,
		__round_jiffies_relative(event_scan_delay, cpu));

	cpus_read_unlock();
}

#ifdef CONFIG_PPC64
static void __init retrieve_nvram_error_log(void)
{
	unsigned int err_type ;
	int rc ;

	/* See if we have any error stored in NVRAM */
	memset(logdata, 0, rtas_error_log_max);
	rc = nvram_read_error_log(logdata, rtas_error_log_max,
	                          &err_type, &error_log_cnt);
	/* We can use rtas_log_buf now */
	logging_enabled = 1;
	if (!rc) {
		if (err_type != ERR_FLAG_ALREADY_LOGGED) {
			pSeries_log_error(logdata, err_type | ERR_FLAG_BOOT, 0);
		}
	}
}
#else /* CONFIG_PPC64 */
static void __init retrieve_nvram_error_log(void)
{
}
#endif /* CONFIG_PPC64 */

static void __init start_event_scan(void)
{
	printk(KERN_DEBUG "RTAS daemon started\n");
	pr_debug("rtasd: will sleep for %d milliseconds\n",
		 (30000 / rtas_event_scan_rate));

	/* Retrieve errors from nvram if any */
	retrieve_nvram_error_log();

	schedule_delayed_work_on(cpumask_first(cpu_online_mask),
				 &event_scan_work, event_scan_delay);
}

/* Cancel the rtas event scan work */
void rtas_cancel_event_scan(void)
{
	cancel_delayed_work_sync(&event_scan_work);
}
EXPORT_SYMBOL_GPL(rtas_cancel_event_scan);

static int __init rtas_event_scan_init(void)
{
	int err;

	if (!machine_is(pseries) && !machine_is(chrp))
		return 0;

	/* No RTAS */
	event_scan = rtas_function_token(RTAS_FN_EVENT_SCAN);
	if (event_scan == RTAS_UNKNOWN_SERVICE) {
		printk(KERN_INFO "rtasd: No event-scan on system\n");
		return -ENODEV;
	}

	err = of_property_read_u32(rtas.dev, "rtas-event-scan-rate", &rtas_event_scan_rate);
	if (err) {
		printk(KERN_ERR "rtasd: no rtas-event-scan-rate on system\n");
		return -ENODEV;
	}

	if (!rtas_event_scan_rate) {
		/* Broken firmware: take a rate of zero to mean don't scan */
		printk(KERN_DEBUG "rtasd: scan rate is 0, not scanning\n");
		return 0;
	}

	/* Make room for the sequence number */
	rtas_error_log_max = rtas_get_error_log_max();
	rtas_error_log_buffer_max = rtas_error_log_max + sizeof(int);

	rtas_log_buf = vmalloc(array_size(LOG_NUMBER,
					  rtas_error_log_buffer_max));
	if (!rtas_log_buf) {
		printk(KERN_ERR "rtasd: no memory\n");
		return -ENOMEM;
	}

	start_event_scan();

	return 0;
}
arch_initcall(rtas_event_scan_init);

static int __init rtas_init(void)
{
	struct proc_dir_entry *entry;

	if (!machine_is(pseries) && !machine_is(chrp))
		return 0;

	if (!rtas_log_buf)
		return -ENODEV;

	entry = proc_create("powerpc/rtas/error_log", 0400, NULL,
			    &rtas_log_proc_ops);
	if (!entry)
		printk(KERN_ERR "Failed to create error_log proc entry\n");

	return 0;
}
__initcall(rtas_init);

static int __init surveillance_setup(char *str)
{
	int i;

	/* We only do surveillance on pseries */
	if (!machine_is(pseries))
		return 0;

	if (get_option(&str,&i)) {
		if (i >= 0 && i <= 255)
			surveillance_timeout = i;
	}

	return 1;
}
__setup("surveillance=", surveillance_setup);

static int __init rtasmsgs_setup(char *str)
{
	return (kstrtobool(str, &full_rtas_msgs) == 0);
}
__setup("rtasmsgs=", rtasmsgs_setup);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
	4	*
1da177e4 LT	5	* Communication to userspace based on kernel/printk.c
	6	*/
	7
	8	#include <linux/types.h>
	9	#include <linux/errno.h>
	10	#include <linux/sched.h>
	11	#include <linux/kernel.h>
b10af504	12	#include <linux/of.h>
1da177e4 LT	13	#include <linux/poll.h>
	14	#include <linux/proc_fs.h>
	15	#include <linux/init.h>
	16	#include <linux/vmalloc.h>
	17	#include <linux/spinlock.h>
	18	#include <linux/cpu.h>
f8729e85	19	#include <linux/workqueue.h>
5a0e3ad6	20	#include <linux/slab.h>
675d8ee6	21	#include <linux/topology.h>
1da177e4	22
7c0f6ba6	23	#include <linux/uaccess.h>
1da177e4 LT	24	#include <asm/io.h>
1da177e4 LT	25	#include <asm/rtas.h>
1da177e4	26	#include <asm/nvram.h>
60063497	27	#include <linux/atomic.h>
e8222502	28	#include <asm/machdep.h>
e04fa612	29	#include <asm/topology.h>
1da177e4	30
1da177e4 LT	31
	32	static DEFINE_SPINLOCK(rtasd_log_lock);
	33
541b2755	34	static DECLARE_WAIT_QUEUE_HEAD(rtas_log_wait);
1da177e4 LT	35
	36	static char *rtas_log_buf;
	37	static unsigned long rtas_log_start;
	38	static unsigned long rtas_log_size;
	39
	40	static int surveillance_timeout = -1;
3d541c4b	41
1da177e4 LT	42	static unsigned int rtas_error_log_max;
	43	static unsigned int rtas_error_log_buffer_max;
	44
a4fc3a3c LV	45	/* RTAS service tokens */
	46	static unsigned int event_scan;
	47	static unsigned int rtas_event_scan_rate;
	48
4cc7ecb7	49	static bool full_rtas_msgs;
1da177e4	50
79c0108d	51	/* Stop logging to nvram after first fatal error */
a0c7ce9c TB	52	static int logging_enabled; /* Until we initialize everything,
	53	* make sure we don't try logging
	54	* anything */
0f2342c8	55	static int error_log_cnt;
1da177e4 LT	56
	57	/*
	58	* Since we use 32 bit RTAS, the physical address of this must be below
	59	* 4G or else bad things happen. Allocate this in the kernel data and
	60	* make it big enough.
	61	*/
	62	static unsigned char logdata[RTAS_ERROR_LOG_MAX];
	63
1da177e4 LT	64	static char *rtas_type[] = {
	65	"Unknown", "Retry", "TCE Error", "Internal Device Failure",
	66	"Timeout", "Data Parity", "Address Parity", "Cache Parity",
	67	"Address Invalid", "ECC Uncorrected", "ECC Corrupted",
	68	};
	69
	70	static char *rtas_event_type(int type)
	71	{
	72	if ((type > 0) && (type < 11))
	73	return rtas_type[type];
	74
	75	switch (type) {
	76	case RTAS_TYPE_EPOW:
	77	return "EPOW";
	78	case RTAS_TYPE_PLATFORM:
	79	return "Platform Error";
	80	case RTAS_TYPE_IO:
	81	return "I/O Event";
	82	case RTAS_TYPE_INFO:
	83	return "Platform Information Event";
	84	case RTAS_TYPE_DEALLOC:
	85	return "Resource Deallocation Event";
	86	case RTAS_TYPE_DUMP:
	87	return "Dump Notification Event";
49c68a85 JL	88	case RTAS_TYPE_PRRN:
49c68a85 JL	89	return "Platform Resource Reassignment Event";
4c5d87db OH	90	case RTAS_TYPE_HOTPLUG:
4c5d87db OH	91	return "Hotplug Event";
1da177e4 LT	92	}
	93
	94	return rtas_type[0];
	95	}
	96
	97	/* To see this info, grep RTAS /var/log/messages and each entry
	98	* will be collected together with obvious begin/end.
	99	* There will be a unique identifier on the begin and end lines.
	100	* This will persist across reboots.
	101	*
	102	* format of error logs returned from RTAS:
	103	* bytes (size) : contents
	104	* --------------------------------------------------------
	105	* 0-7 (8) : rtas_error_log
	106	* 8-47 (40) : extended info
	107	* 48-51 (4) : vendor id
	108	* 52-1023 (vendor specific) : location code and debug data
	109	*/
	110	static void printk_log_rtas(char *buf, int len)
	111	{
	112
	113	int i,j,n = 0;
	114	int perline = 16;
	115	char buffer[64];
	116	char * str = "RTAS event";
	117
	118	if (full_rtas_msgs) {
	119	printk(RTAS_DEBUG "%d -------- %s begin --------\n",
	120	error_log_cnt, str);
	121
	122	/*
	123	* Print perline bytes on each line, each line will start
	124	* with RTAS and a changing number, so syslogd will
	125	* print lines that are otherwise the same. Separate every
	126	* 4 bytes with a space.
	127	*/
	128	for (i = 0; i < len; i++) {
	129	j = i % perline;
	130	if (j == 0) {
	131	memset(buffer, 0, sizeof(buffer));
	132	n = sprintf(buffer, "RTAS %d:", i/perline);
	133	}
	134
	135	if ((i % 4) == 0)
	136	n += sprintf(buffer+n, " ");
	137
	138	n += sprintf(buffer+n, "%02x", (unsigned char)buf[i]);
	139
	140	if (j == (perline-1))
	141	printk(KERN_DEBUG "%s\n", buffer);
	142	}
	143	if ((i % perline) != 0)
	144	printk(KERN_DEBUG "%s\n", buffer);
	145
	146	printk(RTAS_DEBUG "%d -------- %s end ----------\n",
	147	error_log_cnt, str);
	148	} else {
	149	struct rtas_error_log errlog = (struct rtas_error_log )buf;
	150
b27e5f93 OH	151	printk(RTAS_DEBUG "event: %d, Type: %s (%d), Severity: %d\n",
	152	error_log_cnt,
	153	rtas_event_type(rtas_error_type(errlog)),
	154	rtas_error_type(errlog),
a08a53ea	155	rtas_error_severity(errlog));
1da177e4 LT	156	}
	157	}
	158
	159	static int log_rtas_len(char * buf)
	160	{
	161	int len;
	162	struct rtas_error_log *err;
a08a53ea	163	uint32_t extended_log_length;
1da177e4 LT	164
	165	/* rtas fixed header */
	166	len = 8;
	167	err = (struct rtas_error_log *)buf;
a08a53ea GK	168	extended_log_length = rtas_error_extended_log_length(err);
a08a53ea GK	169	if (rtas_error_extended(err) && extended_log_length) {
1da177e4 LT	170
1da177e4 LT	171	/* extended header */
a08a53ea	172	len += extended_log_length;
1da177e4 LT	173	}
1da177e4 LT	174
4511dad4 LV	175	if (rtas_error_log_max == 0)
	176	rtas_error_log_max = rtas_get_error_log_max();
	177
1da177e4 LT	178	if (len > rtas_error_log_max)
	179	len = rtas_error_log_max;
	180
	181	return len;
	182	}
	183
	184	/*
	185	* First write to nvram, if fatal error, that is the only
	186	* place we log the info. The error will be picked up
	187	* on the next reboot by rtasd. If not fatal, run the
	188	* method for the type of error. Currently, only RTAS
	189	* errors have methods implemented, but in the future
	190	* there might be a need to store data in nvram before a
	191	* call to panic().
	192	*
	193	* XXX We write to nvram periodically, to indicate error has
	194	* been written and sync'd, but there is a possibility
	195	* that if we don't shutdown correctly, a duplicate error
	196	* record will be created on next reboot.
	197	*/
	198	void pSeries_log_error(char *buf, unsigned int err_type, int fatal)
	199	{
	200	unsigned long offset;
	201	unsigned long s;
	202	int len = 0;
	203
f7ebf352	204	pr_debug("rtasd: logging event\n");
1da177e4 LT	205	if (buf == NULL)
	206	return;
	207
	208	spin_lock_irqsave(&rtasd_log_lock, s);
	209
	210	/* get length and increase count */
	211	switch (err_type & ERR_TYPE_MASK) {
	212	case ERR_TYPE_RTAS_LOG:
	213	len = log_rtas_len(buf);
	214	if (!(err_type & ERR_FLAG_BOOT))
	215	error_log_cnt++;
	216	break;
	217	case ERR_TYPE_KERNEL_PANIC:
	218	default:
64db4cff	219	WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
1da177e4 LT	220	spin_unlock_irqrestore(&rtasd_log_lock, s);
	221	return;
	222	}
	223
3d541c4b	224	#ifdef CONFIG_PPC64
1da177e4	225	/* Write error to NVRAM */
a0c7ce9c	226	if (logging_enabled && !(err_type & ERR_FLAG_BOOT))
0f2342c8	227	nvram_write_error_log(buf, len, err_type, error_log_cnt);
3d541c4b	228	#endif /* CONFIG_PPC64 */
1da177e4 LT	229
	230	/*
	231	* rtas errors can occur during boot, and we do want to capture
	232	* those somewhere, even if nvram isn't ready (why not?), and even
	233	* if rtasd isn't ready. Put them into the boot log, at least.
	234	*/
	235	if ((err_type & ERR_TYPE_MASK) == ERR_TYPE_RTAS_LOG)
	236	printk_log_rtas(buf, len);
	237
	238	/* Check to see if we need to or have stopped logging */
a0c7ce9c TB	239	if (fatal \|\| !logging_enabled) {
a0c7ce9c TB	240	logging_enabled = 0;
64db4cff	241	WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
1da177e4 LT	242	spin_unlock_irqrestore(&rtasd_log_lock, s);
	243	return;
	244	}
	245
	246	/* call type specific method for error */
	247	switch (err_type & ERR_TYPE_MASK) {
	248	case ERR_TYPE_RTAS_LOG:
	249	offset = rtas_error_log_buffer_max *
	250	((rtas_log_start+rtas_log_size) & LOG_NUMBER_MASK);
	251
	252	/* First copy over sequence number */
	253	memcpy(&rtas_log_buf[offset], (void *) &error_log_cnt, sizeof(int));
	254
	255	/* Second copy over error log data */
	256	offset += sizeof(int);
	257	memcpy(&rtas_log_buf[offset], buf, len);
	258
	259	if (rtas_log_size < LOG_NUMBER)
	260	rtas_log_size += 1;
	261	else
	262	rtas_log_start += 1;
	263
64db4cff	264	WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
1da177e4 LT	265	spin_unlock_irqrestore(&rtasd_log_lock, s);
	266	wake_up_interruptible(&rtas_log_wait);
	267	break;
	268	case ERR_TYPE_KERNEL_PANIC:
	269	default:
64db4cff	270	WARN_ON_ONCE(!irqs_disabled()); /* @@@ DEBUG @@@ */
1da177e4 LT	271	spin_unlock_irqrestore(&rtasd_log_lock, s);
	272	return;
	273	}
49c68a85 JL	274	}
49c68a85 JL	275
49c68a85 JL	276	static void handle_rtas_event(const struct rtas_error_log *log)
49c68a85 JL	277	{
91713ac3	278	if (!machine_is(pseries))
a08a53ea	279	return;
49c68a85	280
91713ac3 NL	281	if (rtas_error_type(log) == RTAS_TYPE_PRRN)
91713ac3 NL	282	pr_info_ratelimited("Platform resource reassignment ignored.\n");
1da177e4 LT	283	}
1da177e4 LT	284
1da177e4 LT	285	static int rtas_log_open(struct inode * inode, struct file * file)
	286	{
	287	return 0;
	288	}
	289
	290	static int rtas_log_release(struct inode * inode, struct file * file)
	291	{
	292	return 0;
	293	}
	294
	295	/* This will check if all events are logged, if they are then, we
	296	* know that we can safely clear the events in NVRAM.
	297	* Next we'll sit and wait for something else to log.
	298	*/
	299	static ssize_t rtas_log_read(struct file * file, char __user * buf,
	300	size_t count, loff_t *ppos)
	301	{
	302	int error;
	303	char *tmp;
	304	unsigned long s;
	305	unsigned long offset;
	306
	307	if (!buf \|\| count < rtas_error_log_buffer_max)
	308	return -EINVAL;
	309
	310	count = rtas_error_log_buffer_max;
	311
96d4f267	312	if (!access_ok(buf, count))
1da177e4 LT	313	return -EFAULT;
	314
	315	tmp = kmalloc(count, GFP_KERNEL);
	316	if (!tmp)
	317	return -ENOMEM;
	318
1da177e4	319	spin_lock_irqsave(&rtasd_log_lock, s);
3d541c4b	320
1da177e4	321	/* if it's 0, then we know we got the last one (the one in NVRAM) */
76c31f23 VM	322	while (rtas_log_size == 0) {
	323	if (file->f_flags & O_NONBLOCK) {
	324	spin_unlock_irqrestore(&rtasd_log_lock, s);
	325	error = -EAGAIN;
	326	goto out;
	327	}
1da177e4	328
76c31f23 VM	329	if (!logging_enabled) {
	330	spin_unlock_irqrestore(&rtasd_log_lock, s);
	331	error = -ENODATA;
	332	goto out;
	333	}
3d541c4b	334	#ifdef CONFIG_PPC64
76c31f23	335	nvram_clear_error_log();
3d541c4b	336	#endif /* CONFIG_PPC64 */
1da177e4	337
76c31f23 VM	338	spin_unlock_irqrestore(&rtasd_log_lock, s);
	339	error = wait_event_interruptible(rtas_log_wait, rtas_log_size);
	340	if (error)
	341	goto out;
	342	spin_lock_irqsave(&rtasd_log_lock, s);
	343	}
1da177e4	344
1da177e4 LT	345	offset = rtas_error_log_buffer_max * (rtas_log_start & LOG_NUMBER_MASK);
	346	memcpy(tmp, &rtas_log_buf[offset], count);
	347
	348	rtas_log_start += 1;
	349	rtas_log_size -= 1;
	350	spin_unlock_irqrestore(&rtasd_log_lock, s);
	351
	352	error = copy_to_user(buf, tmp, count) ? -EFAULT : count;
	353	out:
	354	kfree(tmp);
	355	return error;
	356	}
	357
8153a5ea	358	static __poll_t rtas_log_poll(struct file file, poll_table wait)
1da177e4 LT	359	{
	360	poll_wait(file, &rtas_log_wait, wait);
	361	if (rtas_log_size)
a9a08845	362	return EPOLLIN \| EPOLLRDNORM;
1da177e4 LT	363	return 0;
	364	}
	365
97a32539 AD	366	static const struct proc_ops rtas_log_proc_ops = {
	367	.proc_read = rtas_log_read,
	368	.proc_poll = rtas_log_poll,
	369	.proc_open = rtas_log_open,
	370	.proc_release = rtas_log_release,
	371	.proc_lseek = noop_llseek,
1da177e4 LT	372	};
	373
	374	static int enable_surveillance(int timeout)
	375	{
	376	int error;
	377
	378	error = rtas_set_indicator(SURVEILLANCE_TOKEN, 0, timeout);
	379
	380	if (error == 0)
	381	return 0;
	382
	383	if (error == -EINVAL) {
90ddfebe	384	printk(KERN_DEBUG "rtasd: surveillance not supported\n");
1da177e4 LT	385	return 0;
	386	}
	387
	388	printk(KERN_ERR "rtasd: could not update surveillance\n");
	389	return -1;
	390	}
	391
a4fc3a3c	392	static void do_event_scan(void)
1da177e4 LT	393	{
	394	int error;
	395	do {
	396	memset(logdata, 0, rtas_error_log_max);
	397	error = rtas_call(event_scan, 4, 1, NULL,
	398	RTAS_EVENT_SCAN_ALL_EVENTS, 0,
	399	__pa(logdata), rtas_error_log_max);
	400	if (error == -1) {
	401	printk(KERN_ERR "event-scan failed\n");
	402	break;
	403	}
	404
49c68a85	405	if (error == 0) {
675d8ee6 JA	406	if (rtas_error_type((struct rtas_error_log *)logdata) !=
	407	RTAS_TYPE_PRRN)
	408	pSeries_log_error(logdata, ERR_TYPE_RTAS_LOG,
	409	0);
49c68a85 JL	410	handle_rtas_event((struct rtas_error_log *)logdata);
49c68a85 JL	411	}
1da177e4 LT	412
	413	} while(error == 0);
	414	}
	415
f8729e85	416	static void rtas_event_scan(struct work_struct *w);
635218c7	417	static DECLARE_DELAYED_WORK(event_scan_work, rtas_event_scan);
f8729e85 AB	418
	419	/*
	420	* Delay should be at least one second since some machines have problems if
	421	* we call event-scan too quickly.
	422	*/
	423	static unsigned long event_scan_delay = 1*HZ;
	424	static int first_pass = 1;
	425
	426	static void rtas_event_scan(struct work_struct *w)
1da177e4	427	{
f8729e85 AB	428	unsigned int cpu;
	429
	430	do_event_scan();
1da177e4	431
5ae36401	432	cpus_read_lock();
f8729e85	433
9ff0c61d PM	434	/* raw_ OK because just using CPU as starting point. */
9ff0c61d PM	435	cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
d5f86fe3 AB	436	if (cpu >= nr_cpu_ids) {
d5f86fe3 AB	437	cpu = cpumask_first(cpu_online_mask);
f8729e85 AB	438
	439	if (first_pass) {
	440	first_pass = 0;
	441	event_scan_delay = 30*HZ/rtas_event_scan_rate;
	442
	443	if (surveillance_timeout != -1) {
	444	pr_debug("rtasd: enabling surveillance\n");
	445	enable_surveillance(surveillance_timeout);
	446	pr_debug("rtasd: surveillance enabled\n");
	447	}
	448	}
1da177e4	449	}
f8729e85 AB	450
	451	schedule_delayed_work_on(cpu, &event_scan_work,
	452	__round_jiffies_relative(event_scan_delay, cpu));
	453
5ae36401	454	cpus_read_unlock();
1da177e4 LT	455	}
1da177e4 LT	456
3d541c4b	457	#ifdef CONFIG_PPC64
d276960d	458	static void __init retrieve_nvram_error_log(void)
1da177e4	459	{
3d541c4b BH	460	unsigned int err_type ;
3d541c4b BH	461	int rc ;
1da177e4 LT	462
	463	/* See if we have any error stored in NVRAM */
	464	memset(logdata, 0, rtas_error_log_max);
0f2342c8 LV	465	rc = nvram_read_error_log(logdata, rtas_error_log_max,
0f2342c8 LV	466	&err_type, &error_log_cnt);
a0c7ce9c TB	467	/* We can use rtas_log_buf now */
a0c7ce9c TB	468	logging_enabled = 1;
1da177e4 LT	469	if (!rc) {
	470	if (err_type != ERR_FLAG_ALREADY_LOGGED) {
	471	pSeries_log_error(logdata, err_type \| ERR_FLAG_BOOT, 0);
	472	}
	473	}
3d541c4b BH	474	}
3d541c4b BH	475	#else /* CONFIG_PPC64 */
d276960d	476	static void __init retrieve_nvram_error_log(void)
3d541c4b BH	477	{
	478	}
	479	#endif /* CONFIG_PPC64 */
	480
d276960d	481	static void __init start_event_scan(void)
3d541c4b BH	482	{
	483	printk(KERN_DEBUG "RTAS daemon started\n");
	484	pr_debug("rtasd: will sleep for %d milliseconds\n",
	485	(30000 / rtas_event_scan_rate));
	486
25985edc	487	/* Retrieve errors from nvram if any */
6e45273e	488	retrieve_nvram_error_log();
1da177e4	489
d5f86fe3 AB	490	schedule_delayed_work_on(cpumask_first(cpu_online_mask),
d5f86fe3 AB	491	&event_scan_work, event_scan_delay);
1da177e4 LT	492	}
1da177e4 LT	493
df17f56d RN	494	/* Cancel the rtas event scan work */
	495	void rtas_cancel_event_scan(void)
	496	{
	497	cancel_delayed_work_sync(&event_scan_work);
	498	}
	499	EXPORT_SYMBOL_GPL(rtas_cancel_event_scan);
	500
8c6a0a1f	501	static int __init rtas_event_scan_init(void)
1da177e4	502	{
b10af504 NL	503	int err;
b10af504 NL	504
3d541c4b	505	if (!machine_is(pseries) && !machine_is(chrp))
799d6046 PM	506	return 0;
	507
	508	/* No RTAS */
08273c9f	509	event_scan = rtas_function_token(RTAS_FN_EVENT_SCAN);
a4fc3a3c	510	if (event_scan == RTAS_UNKNOWN_SERVICE) {
3d541c4b	511	printk(KERN_INFO "rtasd: No event-scan on system\n");
49c28e4e	512	return -ENODEV;
1da177e4 LT	513	}
1da177e4 LT	514
b10af504 NL	515	err = of_property_read_u32(rtas.dev, "rtas-event-scan-rate", &rtas_event_scan_rate);
b10af504 NL	516	if (err) {
4511dad4 LV	517	printk(KERN_ERR "rtasd: no rtas-event-scan-rate on system\n");
	518	return -ENODEV;
	519	}
	520
7358650e ME	521	if (!rtas_event_scan_rate) {
	522	/* Broken firmware: take a rate of zero to mean don't scan */
	523	printk(KERN_DEBUG "rtasd: scan rate is 0, not scanning\n");
	524	return 0;
	525	}
	526
4511dad4 LV	527	/* Make room for the sequence number */
	528	rtas_error_log_max = rtas_get_error_log_max();
	529	rtas_error_log_buffer_max = rtas_error_log_max + sizeof(int);
	530
42bc47b3 KC	531	rtas_log_buf = vmalloc(array_size(LOG_NUMBER,
42bc47b3 KC	532	rtas_error_log_buffer_max));
4511dad4 LV	533	if (!rtas_log_buf) {
	534	printk(KERN_ERR "rtasd: no memory\n");
	535	return -ENOMEM;
	536	}
	537
8c6a0a1f GK	538	start_event_scan();
	539
	540	return 0;
	541	}
	542	arch_initcall(rtas_event_scan_init);
	543
	544	static int __init rtas_init(void)
	545	{
	546	struct proc_dir_entry *entry;
	547
	548	if (!machine_is(pseries) && !machine_is(chrp))
	549	return 0;
	550
	551	if (!rtas_log_buf)
	552	return -ENODEV;
	553
57ad583f	554	entry = proc_create("powerpc/rtas/error_log", 0400, NULL,
97a32539	555	&rtas_log_proc_ops);
66747138	556	if (!entry)
1da177e4 LT	557	printk(KERN_ERR "Failed to create error_log proc entry\n");
1da177e4 LT	558
1da177e4 LT	559	return 0;
1da177e4 LT	560	}
3d541c4b	561	__initcall(rtas_init);
1da177e4 LT	562
	563	static int __init surveillance_setup(char *str)
	564	{
	565	int i;
	566
3d541c4b BH	567	/* We only do surveillance on pseries */
	568	if (!machine_is(pseries))
	569	return 0;
	570
1da177e4 LT	571	if (get_option(&str,&i)) {
	572	if (i >= 0 && i <= 255)
	573	surveillance_timeout = i;
	574	}
	575
	576	return 1;
	577	}
3d541c4b	578	__setup("surveillance=", surveillance_setup);
1da177e4 LT	579
	580	static int __init rtasmsgs_setup(char *str)
	581	{
4cc7ecb7	582	return (kstrtobool(str, &full_rtas_msgs) == 0);
1da177e4	583	}
1da177e4	584	__setup("rtasmsgs=", rtasmsgs_setup);