From e7d162faa6d067777548cb98d55206cf7cd3438e Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 25 Dec 2015 16:01:41 -0800 Subject: [PATCH] watchdog: diag288: Stop re-using watchdog core internal flags A watchdog driver should not use watchdog subsystem internal flags. Use a driver variable and flag instead to maintain the watchdog state and to determine if a suspend operation is possible or not. Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/diag288_wdt.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/drivers/watchdog/diag288_wdt.c b/drivers/watchdog/diag288_wdt.c index 3db9d0e0673d..861d3d3133f8 100644 --- a/drivers/watchdog/diag288_wdt.c +++ b/drivers/watchdog/diag288_wdt.c @@ -106,6 +106,10 @@ static int __diag288_lpar(unsigned int func, unsigned int timeout, return __diag288(func, timeout, action, 0); } +static unsigned long wdt_status; + +#define DIAG_WDOG_BUSY 0 + static int wdt_start(struct watchdog_device *dev) { char *ebc_cmd; @@ -113,12 +117,17 @@ static int wdt_start(struct watchdog_device *dev) int ret; unsigned int func; + if (test_and_set_bit(DIAG_WDOG_BUSY, &wdt_status)) + return -EBUSY; + ret = -ENODEV; if (MACHINE_IS_VM) { ebc_cmd = kmalloc(MAX_CMDLEN, GFP_KERNEL); - if (!ebc_cmd) + if (!ebc_cmd) { + clear_bit(DIAG_WDOG_BUSY, &wdt_status); return -ENOMEM; + } len = strlcpy(ebc_cmd, wdt_cmd, MAX_CMDLEN); ASCEBC(ebc_cmd, MAX_CMDLEN); EBC_TOUPPER(ebc_cmd, MAX_CMDLEN); @@ -135,6 +144,7 @@ static int wdt_start(struct watchdog_device *dev) if (ret) { pr_err("The watchdog cannot be activated\n"); + clear_bit(DIAG_WDOG_BUSY, &wdt_status); return ret; } return 0; @@ -146,6 +156,9 @@ static int wdt_stop(struct watchdog_device *dev) diag_stat_inc(DIAG_STAT_X288); ret = __diag288(WDT_FUNC_CANCEL, 0, 0, 0); + + clear_bit(DIAG_WDOG_BUSY, &wdt_status); + return ret; } @@ -220,17 +233,10 @@ static struct watchdog_device wdt_dev = { * 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 wdt_suspend(void) { - if (test_and_set_bit(WDOG_DEV_OPEN, &wdt_dev.status)) { - pr_err("Linux cannot be suspended while the watchdog is in use\n"); - return notifier_from_errno(-EBUSY); - } - if (test_bit(WDOG_ACTIVE, &wdt_dev.status)) { - clear_bit(WDOG_DEV_OPEN, &wdt_dev.status); + if (test_and_set_bit(DIAG_WDOG_BUSY, &wdt_status)) { pr_err("Linux cannot be suspended while the watchdog is in use\n"); return notifier_from_errno(-EBUSY); } @@ -239,7 +245,7 @@ static int wdt_suspend(void) static int wdt_resume(void) { - clear_bit(WDOG_DEV_OPEN, &wdt_dev.status); + clear_bit(DIAG_WDOG_BUSY, &wdt_status); return NOTIFY_DONE; }