s390/watchdog: use watchdog API (f7a94db4) · Commits · e / devices / android_kernel_fairphone_FP3

arch/s390/configs/default_defconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -456,6 +456,7 @@ CONFIG_TN3270_FS=y
		CONFIG_WATCHDOG=y
		CONFIG_WATCHDOG_NOWAYOUT=y
		CONFIG_SOFT_WATCHDOG=m
		CONFIG_DIAG288_WATCHDOG=m
		# CONFIG_HID is not set
		# CONFIG_USB_SUPPORT is not set
		CONFIG_INFINIBAND=m

arch/s390/configs/gcov_defconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -453,6 +453,7 @@ CONFIG_TN3270_FS=y
		CONFIG_WATCHDOG=y
		CONFIG_WATCHDOG_NOWAYOUT=y
		CONFIG_SOFT_WATCHDOG=m
		CONFIG_DIAG288_WATCHDOG=m
		# CONFIG_HID is not set
		# CONFIG_USB_SUPPORT is not set
		CONFIG_INFINIBAND=m

arch/s390/configs/performance_defconfig

+1 −0

Original line number	Diff line number	Diff line
		@@ -451,6 +451,7 @@ CONFIG_TN3270_FS=y
		CONFIG_WATCHDOG=y
		CONFIG_WATCHDOG_NOWAYOUT=y
		CONFIG_SOFT_WATCHDOG=m
		CONFIG_DIAG288_WATCHDOG=m
		# CONFIG_HID is not set
		# CONFIG_USB_SUPPORT is not set
		CONFIG_INFINIBAND=m

drivers/s390/char/Makefile

+0 −1

Original line number	Diff line number	Diff line
		@@ -19,7 +19,6 @@ obj-$(CONFIG_SCLP_VT220_TTY) += sclp_vt220.o
		obj-$(CONFIG_SCLP_CPI) += sclp_cpi.o
		obj-$(CONFIG_SCLP_ASYNC) += sclp_async.o

		obj-$(CONFIG_ZVM_WATCHDOG) += vmwatchdog.o
		obj-$(CONFIG_VMLOGRDR) += vmlogrdr.o
		obj-$(CONFIG_VMCP) += vmcp.o

drivers/s390/char/vmwatchdog.c

deleted100644 → 0

+0 −338

Original line number	Diff line number	Diff line
		/*
		* Watchdog implementation based on z/VM Watchdog Timer API
		*
		* Copyright IBM Corp. 2004, 2009
		*
		* The user space watchdog daemon can use this driver as
		* /dev/vmwatchdog to have z/VM execute the specified CP
		* command when the timeout expires. The default command is
		* "IPL", which which cause an immediate reboot.
		*/
		#define KMSG_COMPONENT "vmwatchdog"
		#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

		#include <linux/init.h>
		#include <linux/fs.h>
		#include <linux/kernel.h>
		#include <linux/miscdevice.h>
		#include <linux/module.h>
		#include <linux/moduleparam.h>
		#include <linux/slab.h>
		#include <linux/suspend.h>
		#include <linux/watchdog.h>

		#include <asm/ebcdic.h>
		#include <asm/io.h>
		#include <asm/uaccess.h>

		#define MAX_CMDLEN 240
		#define MIN_INTERVAL 15
		static char vmwdt_cmd[MAX_CMDLEN] = "IPL";
		static bool vmwdt_conceal;

		static bool vmwdt_nowayout = WATCHDOG_NOWAYOUT;

		MODULE_LICENSE("GPL");
		MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
		MODULE_DESCRIPTION("z/VM Watchdog Timer");
		module_param_string(cmd, vmwdt_cmd, MAX_CMDLEN, 0644);
		MODULE_PARM_DESC(cmd, "CP command that is run when the watchdog triggers");
		module_param_named(conceal, vmwdt_conceal, bool, 0644);
		MODULE_PARM_DESC(conceal, "Enable the CONCEAL CP option while the watchdog "
		" is active");
		module_param_named(nowayout, vmwdt_nowayout, bool, 0);
		MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"
		" (default=CONFIG_WATCHDOG_NOWAYOUT)");
		MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);

		static unsigned int vmwdt_interval = 60;
		static unsigned long vmwdt_is_open;
		static int vmwdt_expect_close;

		static DEFINE_MUTEX(vmwdt_mutex);

		#define VMWDT_OPEN 0 /* devnode is open or suspend in progress */
		#define VMWDT_RUNNING 1 /* The watchdog is armed */

		enum vmwdt_func {
		/* function codes */
		wdt_init = 0,
		wdt_change = 1,
		wdt_cancel = 2,
		/* flags */
		wdt_conceal = 0x80000000,
		};

		static int __diag288(enum vmwdt_func func, unsigned int timeout,
		char *cmd, size_t len)
		{
		register unsigned long __func asm("2") = func;
		register unsigned long __timeout asm("3") = timeout;
		register unsigned long __cmdp asm("4") = virt_to_phys(cmd);
		register unsigned long __cmdl asm("5") = len;
		int err;

		err = -EINVAL;
		asm volatile(
		" diag %1,%3,0x288\n"
		"0: la %0,0\n"
		"1:\n"
		EX_TABLE(0b,1b)
		: "+d" (err) : "d"(__func), "d"(__timeout),
		"d"(__cmdp), "d"(__cmdl) : "1", "cc");
		return err;
		}

		static int vmwdt_keepalive(void)
		{
		/* we allocate new memory every time to avoid having
		* to track the state. static allocation is not an
		* option since that might not be contiguous in real
		* storage in case of a modular build */
		static char *ebc_cmd;
		size_t len;
		int ret;
		unsigned int func;

		ebc_cmd = kmalloc(MAX_CMDLEN, GFP_KERNEL);
		if (!ebc_cmd)
		return -ENOMEM;

		len = strlcpy(ebc_cmd, vmwdt_cmd, MAX_CMDLEN);
		ASCEBC(ebc_cmd, MAX_CMDLEN);
		EBC_TOUPPER(ebc_cmd, MAX_CMDLEN);

		func = vmwdt_conceal ? (wdt_init \| wdt_conceal) : wdt_init;
		set_bit(VMWDT_RUNNING, &vmwdt_is_open);
		ret = __diag288(func, vmwdt_interval, ebc_cmd, len);
		WARN_ON(ret != 0);
		kfree(ebc_cmd);
		return ret;
		}

		static int vmwdt_disable(void)
		{
		char cmd[] = {'\0'};
		int ret = __diag288(wdt_cancel, 0, cmd, 0);
		WARN_ON(ret != 0);
		clear_bit(VMWDT_RUNNING, &vmwdt_is_open);
		return ret;
		}

		static int __init vmwdt_probe(void)
		{
		/* there is no real way to see if the watchdog is supported,
		* so we try initializing it with a NOP command ("BEGIN")
		* that won't cause any harm even if the following disable
		* fails for some reason */
		char ebc_begin[] = {
		194, 197, 199, 201, 213
		};
		if (__diag288(wdt_init, 15, ebc_begin, sizeof(ebc_begin)) != 0)
		return -EINVAL;
		return vmwdt_disable();
		}

		static int vmwdt_open(struct inode i, struct file f)
		{
		int ret;
		if (test_and_set_bit(VMWDT_OPEN, &vmwdt_is_open))
		return -EBUSY;
		ret = vmwdt_keepalive();
		if (ret)
		clear_bit(VMWDT_OPEN, &vmwdt_is_open);
		return ret ? ret : nonseekable_open(i, f);
		}

		static int vmwdt_close(struct inode i, struct file f)
		{
		if (vmwdt_expect_close == 42)
		vmwdt_disable();
		vmwdt_expect_close = 0;
		clear_bit(VMWDT_OPEN, &vmwdt_is_open);
		return 0;
		}

		static struct watchdog_info vmwdt_info = {
		.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING \| WDIOF_MAGICCLOSE,
		.firmware_version = 0,
		.identity = "z/VM Watchdog Timer",
		};

		static int __vmwdt_ioctl(unsigned int cmd, unsigned long arg)
		{
		switch (cmd) {
		case WDIOC_GETSUPPORT:
		if (copy_to_user((void __user *)arg, &vmwdt_info,
		sizeof(vmwdt_info)))
		return -EFAULT;
		return 0;
		case WDIOC_GETSTATUS:
		case WDIOC_GETBOOTSTATUS:
		return put_user(0, (int __user *)arg);
		case WDIOC_GETTEMP:
		return -EINVAL;
		case WDIOC_SETOPTIONS:
		{
		int options, ret;
		if (get_user(options, (int __user *)arg))
		return -EFAULT;
		ret = -EINVAL;
		if (options & WDIOS_DISABLECARD) {
		ret = vmwdt_disable();
		if (ret)
		return ret;
		}
		if (options & WDIOS_ENABLECARD) {
		ret = vmwdt_keepalive();
		}
		return ret;
		}
		case WDIOC_GETTIMEOUT:
		return put_user(vmwdt_interval, (int __user *)arg);
		case WDIOC_SETTIMEOUT:
		{
		int interval;
		if (get_user(interval, (int __user *)arg))
		return -EFAULT;
		if (interval < MIN_INTERVAL)
		return -EINVAL;
		vmwdt_interval = interval;
		}
		return vmwdt_keepalive();
		case WDIOC_KEEPALIVE:
		return vmwdt_keepalive();
		}
		return -EINVAL;
		}

		static long vmwdt_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
		{
		int rc;

		mutex_lock(&vmwdt_mutex);
		rc = __vmwdt_ioctl(cmd, arg);
		mutex_unlock(&vmwdt_mutex);
		return (long) rc;
		}

		static ssize_t vmwdt_write(struct file f, const char __user buf,
		size_t count, loff_t *ppos)
		{
		if(count) {
		if (!vmwdt_nowayout) {
		size_t i;

		/* note: just in case someone wrote the magic character
		* five months ago... */
		vmwdt_expect_close = 0;

		for (i = 0; i != count; i++) {
		char c;
		if (get_user(c, buf+i))
		return -EFAULT;
		if (c == 'V')
		vmwdt_expect_close = 42;
		}
		}
		/* someone wrote to us, we should restart timer */
		vmwdt_keepalive();
		}
		return count;
		}

		static int vmwdt_resume(void)
		{
		clear_bit(VMWDT_OPEN, &vmwdt_is_open);
		return NOTIFY_DONE;
		}

		/*
		* It makes no sense to go into suspend while the watchdog is running.
		* Depending on the memory size, the watchdog might trigger, while we
		* are still saving the memory.
		* We reuse the open flag to ensure that suspend and watchdog open are
		* exclusive operations
		*/
		static int vmwdt_suspend(void)
		{
		if (test_and_set_bit(VMWDT_OPEN, &vmwdt_is_open)) {
		pr_err("The system cannot be suspended while the watchdog"
		" is in use\n");
		return notifier_from_errno(-EBUSY);
		}
		if (test_bit(VMWDT_RUNNING, &vmwdt_is_open)) {
		clear_bit(VMWDT_OPEN, &vmwdt_is_open);
		pr_err("The system cannot be suspended while the watchdog"
		" is running\n");
		return notifier_from_errno(-EBUSY);
		}
		return NOTIFY_DONE;
		}

		/*
		* This function is called for suspend and resume.
		*/
		static int vmwdt_power_event(struct notifier_block *this, unsigned long event,
		void *ptr)
		{
		switch (event) {
		case PM_POST_HIBERNATION:
		case PM_POST_SUSPEND:
		return vmwdt_resume();
		case PM_HIBERNATION_PREPARE:
		case PM_SUSPEND_PREPARE:
		return vmwdt_suspend();
		default:
		return NOTIFY_DONE;
		}
		}

		static struct notifier_block vmwdt_power_notifier = {
		.notifier_call = vmwdt_power_event,
		};

		static const struct file_operations vmwdt_fops = {
		.open = &vmwdt_open,
		.release = &vmwdt_close,
		.unlocked_ioctl = &vmwdt_ioctl,
		.write = &vmwdt_write,
		.owner = THIS_MODULE,
		.llseek = noop_llseek,
		};

		static struct miscdevice vmwdt_dev = {
		.minor = WATCHDOG_MINOR,
		.name = "watchdog",
		.fops = &vmwdt_fops,
		};

		static int __init vmwdt_init(void)
		{
		int ret;

		ret = vmwdt_probe();
		if (ret)
		return ret;
		ret = register_pm_notifier(&vmwdt_power_notifier);
		if (ret)
		return ret;
		/*
		* misc_register() has to be the last action in module_init(), because
		* file operations will be available right after this.
		*/
		ret = misc_register(&vmwdt_dev);
		if (ret) {
		unregister_pm_notifier(&vmwdt_power_notifier);
		return ret;
		}
		return 0;
		}
		module_init(vmwdt_init);

		static void __exit vmwdt_exit(void)
		{
		unregister_pm_notifier(&vmwdt_power_notifier);
		misc_deregister(&vmwdt_dev);
		}
		module_exit(vmwdt_exit);