[WATCHDOG 16/57] iop: watchdog switch to unlocked_ioctl

Review and switch to unlocked_ioctl

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

1 files changed, 24 insertions, 22 deletions

diff --git a/drivers/watchdog/iop_wdt.c b/drivers/watchdog/iop_wdt.c
index bbbd91af754d..e54c888d2afe 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;
 }