From: Alan Cox Date: Mon, 19 May 2008 13:06:14 +0000 (+0100) Subject: [WATCHDOG 16/57] iop: watchdog switch to unlocked_ioctl X-Git-Tag: v2.6.27-rc3~81^2~13^2~41 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=02e3814e193ff798676793016851bc222366dc6a;p=linux-2.6-omap-h63xx.git [WATCHDOG 16/57] iop: watchdog switch to unlocked_ioctl Review and switch to unlocked_ioctl Signed-off-by: Alan Cox Signed-off-by: Wim Van Sebroeck --- diff --git a/drivers/watchdog/iop_wdt.c b/drivers/watchdog/iop_wdt.c index bbbd91af754..e54c888d2af 100644 --- a/drivers/watchdog/iop_wdt.c +++ b/drivers/watchdog/iop_wdt.c @@ -37,6 +37,7 @@ static int nowayout = WATCHDOG_NOWAYOUT; static unsigned long wdt_status; static unsigned long boot_status; +static spinlock_t wdt_lock; #define WDT_IN_USE 0 #define WDT_OK_TO_CLOSE 1 @@ -68,8 +69,10 @@ static void wdt_enable(void) /* Arm and enable the Timer to starting counting down from 0xFFFF.FFFF * Takes approx. 10.7s to timeout */ + spin_lock(&wdt_lock); write_wdtcr(IOP_WDTCR_EN_ARM); write_wdtcr(IOP_WDTCR_EN); + spin_unlock(&wdt_lock); } /* returns 0 if the timer was successfully disabled */ @@ -77,9 +80,11 @@ static int wdt_disable(void) { /* Stop Counting */ if (wdt_supports_disable()) { + spin_lock(&wdt_lock); write_wdtcr(IOP_WDTCR_DIS_ARM); write_wdtcr(IOP_WDTCR_DIS); clear_bit(WDT_ENABLED, &wdt_status); + spin_unlock(&wdt_lock); printk(KERN_INFO "WATCHDOG: Disabled\n"); return 0; } else @@ -92,16 +97,12 @@ static int iop_wdt_open(struct inode *inode, struct file *file) return -EBUSY; clear_bit(WDT_OK_TO_CLOSE, &wdt_status); - wdt_enable(); - set_bit(WDT_ENABLED, &wdt_status); - return nonseekable_open(inode, file); } -static ssize_t -iop_wdt_write(struct file *file, const char *data, size_t len, +static ssize_t iop_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos) { if (len) { @@ -121,41 +122,39 @@ iop_wdt_write(struct file *file, const char *data, size_t len, } wdt_enable(); } - return len; } -static struct watchdog_info ident = { +static const struct watchdog_info ident = { .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, .identity = "iop watchdog", }; -static int -iop_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, - unsigned long arg) +static long iop_wdt_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) { int options; int ret = -ENOTTY; + int __user *argp = (int __user *)arg; switch (cmd) { case WDIOC_GETSUPPORT: - if (copy_to_user - ((struct watchdog_info *)arg, &ident, sizeof ident)) + if (copy_to_user(argp, &ident, sizeof ident)) ret = -EFAULT; else ret = 0; break; case WDIOC_GETSTATUS: - ret = put_user(0, (int *)arg); + ret = put_user(0, argp); break; case WDIOC_GETBOOTSTATUS: - ret = put_user(boot_status, (int *)arg); + ret = put_user(boot_status, argp); break; case WDIOC_GETTIMEOUT: - ret = put_user(iop_watchdog_timeout(), (int *)arg); + ret = put_user(iop_watchdog_timeout(), argp); break; case WDIOC_KEEPALIVE: @@ -177,14 +176,12 @@ iop_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, } else ret = 0; } - if (options & WDIOS_ENABLECARD) { wdt_enable(); ret = 0; } break; } - return ret; } @@ -214,7 +211,7 @@ static const struct file_operations iop_wdt_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .write = iop_wdt_write, - .ioctl = iop_wdt_ioctl, + .unlocked_ioctl = iop_wdt_ioctl, .open = iop_wdt_open, .release = iop_wdt_release, }; @@ -229,10 +226,8 @@ static int __init iop_wdt_init(void) { int ret; - ret = misc_register(&iop_wdt_miscdev); - if (ret == 0) - printk("iop watchdog timer: timeout %lu sec\n", - iop_watchdog_timeout()); + spin_lock_init(&wdt_lock); + /* check if the reset was caused by the watchdog timer */ boot_status = (read_rcsr() & IOP_RCSR_WDT) ? WDIOF_CARDRESET : 0; @@ -242,6 +237,13 @@ static int __init iop_wdt_init(void) */ write_wdtsr(IOP13XX_WDTCR_IB_RESET); + /* Register after we have the device set up so we cannot race + with an open */ + ret = misc_register(&iop_wdt_miscdev); + if (ret == 0) + printk("iop watchdog timer: timeout %lu sec\n", + iop_watchdog_timeout()); + return ret; }