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@@ -1,338 +0,0 @@
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-/*
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- * Watchdog implementation based on z/VM Watchdog Timer API
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- *
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- * Copyright IBM Corp. 2004, 2009
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- *
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- * The user space watchdog daemon can use this driver as
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- * /dev/vmwatchdog to have z/VM execute the specified CP
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- * command when the timeout expires. The default command is
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- * "IPL", which which cause an immediate reboot.
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- */
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-#define KMSG_COMPONENT "vmwatchdog"
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-#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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-
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-#include <linux/init.h>
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-#include <linux/fs.h>
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-#include <linux/kernel.h>
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-#include <linux/miscdevice.h>
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-#include <linux/module.h>
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-#include <linux/moduleparam.h>
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-#include <linux/slab.h>
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-#include <linux/suspend.h>
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-#include <linux/watchdog.h>
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-
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-#include <asm/ebcdic.h>
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-#include <asm/io.h>
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-#include <asm/uaccess.h>
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-
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-#define MAX_CMDLEN 240
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-#define MIN_INTERVAL 15
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-static char vmwdt_cmd[MAX_CMDLEN] = "IPL";
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-static bool vmwdt_conceal;
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-
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-static bool vmwdt_nowayout = WATCHDOG_NOWAYOUT;
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-
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-MODULE_LICENSE("GPL");
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-MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
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-MODULE_DESCRIPTION("z/VM Watchdog Timer");
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-module_param_string(cmd, vmwdt_cmd, MAX_CMDLEN, 0644);
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-MODULE_PARM_DESC(cmd, "CP command that is run when the watchdog triggers");
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-module_param_named(conceal, vmwdt_conceal, bool, 0644);
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-MODULE_PARM_DESC(conceal, "Enable the CONCEAL CP option while the watchdog "
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- " is active");
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-module_param_named(nowayout, vmwdt_nowayout, bool, 0);
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-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"
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- " (default=CONFIG_WATCHDOG_NOWAYOUT)");
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-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
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-
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-static unsigned int vmwdt_interval = 60;
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-static unsigned long vmwdt_is_open;
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-static int vmwdt_expect_close;
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-
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-static DEFINE_MUTEX(vmwdt_mutex);
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-
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-#define VMWDT_OPEN 0 /* devnode is open or suspend in progress */
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-#define VMWDT_RUNNING 1 /* The watchdog is armed */
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-
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-enum vmwdt_func {
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- /* function codes */
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- wdt_init = 0,
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- wdt_change = 1,
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- wdt_cancel = 2,
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- /* flags */
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- wdt_conceal = 0x80000000,
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-};
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-
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-static int __diag288(enum vmwdt_func func, unsigned int timeout,
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- char *cmd, size_t len)
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-{
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- register unsigned long __func asm("2") = func;
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- register unsigned long __timeout asm("3") = timeout;
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- register unsigned long __cmdp asm("4") = virt_to_phys(cmd);
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- register unsigned long __cmdl asm("5") = len;
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- int err;
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-
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- err = -EINVAL;
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- asm volatile(
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- " diag %1,%3,0x288\n"
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- "0: la %0,0\n"
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- "1:\n"
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- EX_TABLE(0b,1b)
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- : "+d" (err) : "d"(__func), "d"(__timeout),
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- "d"(__cmdp), "d"(__cmdl) : "1", "cc");
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- return err;
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-}
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-
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-static int vmwdt_keepalive(void)
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-{
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- /* we allocate new memory every time to avoid having
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- * to track the state. static allocation is not an
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- * option since that might not be contiguous in real
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- * storage in case of a modular build */
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- static char *ebc_cmd;
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- size_t len;
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- int ret;
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- unsigned int func;
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-
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- ebc_cmd = kmalloc(MAX_CMDLEN, GFP_KERNEL);
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- if (!ebc_cmd)
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- return -ENOMEM;
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-
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- len = strlcpy(ebc_cmd, vmwdt_cmd, MAX_CMDLEN);
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- ASCEBC(ebc_cmd, MAX_CMDLEN);
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- EBC_TOUPPER(ebc_cmd, MAX_CMDLEN);
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-
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- func = vmwdt_conceal ? (wdt_init | wdt_conceal) : wdt_init;
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- set_bit(VMWDT_RUNNING, &vmwdt_is_open);
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- ret = __diag288(func, vmwdt_interval, ebc_cmd, len);
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- WARN_ON(ret != 0);
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- kfree(ebc_cmd);
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- return ret;
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-}
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-
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-static int vmwdt_disable(void)
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-{
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- char cmd[] = {'\0'};
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- int ret = __diag288(wdt_cancel, 0, cmd, 0);
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- WARN_ON(ret != 0);
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- clear_bit(VMWDT_RUNNING, &vmwdt_is_open);
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- return ret;
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-}
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-
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-static int __init vmwdt_probe(void)
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-{
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- /* there is no real way to see if the watchdog is supported,
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- * so we try initializing it with a NOP command ("BEGIN")
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- * that won't cause any harm even if the following disable
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- * fails for some reason */
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- char ebc_begin[] = {
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- 194, 197, 199, 201, 213
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- };
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- if (__diag288(wdt_init, 15, ebc_begin, sizeof(ebc_begin)) != 0)
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- return -EINVAL;
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- return vmwdt_disable();
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-}
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-
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-static int vmwdt_open(struct inode *i, struct file *f)
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-{
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- int ret;
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- if (test_and_set_bit(VMWDT_OPEN, &vmwdt_is_open))
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- return -EBUSY;
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- ret = vmwdt_keepalive();
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- if (ret)
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- clear_bit(VMWDT_OPEN, &vmwdt_is_open);
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- return ret ? ret : nonseekable_open(i, f);
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-}
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-
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-static int vmwdt_close(struct inode *i, struct file *f)
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-{
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- if (vmwdt_expect_close == 42)
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- vmwdt_disable();
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- vmwdt_expect_close = 0;
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- clear_bit(VMWDT_OPEN, &vmwdt_is_open);
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- return 0;
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-}
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-
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-static struct watchdog_info vmwdt_info = {
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- .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
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- .firmware_version = 0,
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- .identity = "z/VM Watchdog Timer",
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-};
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-
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-static int __vmwdt_ioctl(unsigned int cmd, unsigned long arg)
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-{
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- switch (cmd) {
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- case WDIOC_GETSUPPORT:
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- if (copy_to_user((void __user *)arg, &vmwdt_info,
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- sizeof(vmwdt_info)))
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- return -EFAULT;
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- return 0;
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- case WDIOC_GETSTATUS:
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- case WDIOC_GETBOOTSTATUS:
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- return put_user(0, (int __user *)arg);
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- case WDIOC_GETTEMP:
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- return -EINVAL;
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- case WDIOC_SETOPTIONS:
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- {
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- int options, ret;
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- if (get_user(options, (int __user *)arg))
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- return -EFAULT;
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- ret = -EINVAL;
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- if (options & WDIOS_DISABLECARD) {
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- ret = vmwdt_disable();
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- if (ret)
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- return ret;
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- }
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- if (options & WDIOS_ENABLECARD) {
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- ret = vmwdt_keepalive();
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- }
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- return ret;
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- }
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- case WDIOC_GETTIMEOUT:
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- return put_user(vmwdt_interval, (int __user *)arg);
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- case WDIOC_SETTIMEOUT:
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- {
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- int interval;
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- if (get_user(interval, (int __user *)arg))
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- return -EFAULT;
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- if (interval < MIN_INTERVAL)
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- return -EINVAL;
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- vmwdt_interval = interval;
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- }
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- return vmwdt_keepalive();
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- case WDIOC_KEEPALIVE:
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- return vmwdt_keepalive();
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- }
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- return -EINVAL;
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-}
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-
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-static long vmwdt_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
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-{
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- int rc;
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-
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- mutex_lock(&vmwdt_mutex);
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- rc = __vmwdt_ioctl(cmd, arg);
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- mutex_unlock(&vmwdt_mutex);
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- return (long) rc;
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-}
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-
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-static ssize_t vmwdt_write(struct file *f, const char __user *buf,
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- size_t count, loff_t *ppos)
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-{
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- if(count) {
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- if (!vmwdt_nowayout) {
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- size_t i;
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-
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- /* note: just in case someone wrote the magic character
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- * five months ago... */
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- vmwdt_expect_close = 0;
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-
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- for (i = 0; i != count; i++) {
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- char c;
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- if (get_user(c, buf+i))
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- return -EFAULT;
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- if (c == 'V')
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- vmwdt_expect_close = 42;
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- }
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- }
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- /* someone wrote to us, we should restart timer */
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- vmwdt_keepalive();
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- }
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- return count;
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-}
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-
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-static int vmwdt_resume(void)
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-{
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- clear_bit(VMWDT_OPEN, &vmwdt_is_open);
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- return NOTIFY_DONE;
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-}
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-
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-/*
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- * It makes no sense to go into suspend while the watchdog is running.
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- * Depending on the memory size, the watchdog might trigger, while we
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- * are still saving the memory.
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- * We reuse the open flag to ensure that suspend and watchdog open are
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- * exclusive operations
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- */
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-static int vmwdt_suspend(void)
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-{
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- if (test_and_set_bit(VMWDT_OPEN, &vmwdt_is_open)) {
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- pr_err("The system cannot be suspended while the watchdog"
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- " is in use\n");
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- return notifier_from_errno(-EBUSY);
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- }
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- if (test_bit(VMWDT_RUNNING, &vmwdt_is_open)) {
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- clear_bit(VMWDT_OPEN, &vmwdt_is_open);
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- pr_err("The system cannot be suspended while the watchdog"
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- " is running\n");
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- return notifier_from_errno(-EBUSY);
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- }
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- return NOTIFY_DONE;
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-}
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-
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-/*
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- * This function is called for suspend and resume.
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- */
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-static int vmwdt_power_event(struct notifier_block *this, unsigned long event,
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- void *ptr)
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-{
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- switch (event) {
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- case PM_POST_HIBERNATION:
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- case PM_POST_SUSPEND:
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- return vmwdt_resume();
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- case PM_HIBERNATION_PREPARE:
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- case PM_SUSPEND_PREPARE:
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- return vmwdt_suspend();
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- default:
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- return NOTIFY_DONE;
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- }
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-}
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-
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-static struct notifier_block vmwdt_power_notifier = {
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- .notifier_call = vmwdt_power_event,
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-};
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-
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-static const struct file_operations vmwdt_fops = {
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- .open = &vmwdt_open,
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- .release = &vmwdt_close,
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- .unlocked_ioctl = &vmwdt_ioctl,
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- .write = &vmwdt_write,
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- .owner = THIS_MODULE,
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- .llseek = noop_llseek,
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-};
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-
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-static struct miscdevice vmwdt_dev = {
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- .minor = WATCHDOG_MINOR,
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- .name = "watchdog",
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- .fops = &vmwdt_fops,
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-};
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-
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-static int __init vmwdt_init(void)
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-{
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- int ret;
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-
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- ret = vmwdt_probe();
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- if (ret)
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- return ret;
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- ret = register_pm_notifier(&vmwdt_power_notifier);
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- if (ret)
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- return ret;
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- /*
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- * misc_register() has to be the last action in module_init(), because
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- * file operations will be available right after this.
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- */
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- ret = misc_register(&vmwdt_dev);
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- if (ret) {
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- unregister_pm_notifier(&vmwdt_power_notifier);
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- return ret;
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- }
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- return 0;
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-}
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-module_init(vmwdt_init);
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-
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-static void __exit vmwdt_exit(void)
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-{
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- unregister_pm_notifier(&vmwdt_power_notifier);
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- misc_deregister(&vmwdt_dev);
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-}
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-module_exit(vmwdt_exit);
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