[PATCH] rtc: Push the BKL down into the driver ioctl method

From: Alan Cox
Date: Thu May 22 2008 - 18:25:10 EST


For now just wrap the main logic, but this driver is a prime candidate
for someone wanting to eliminate the lock entirely

Signed-off-by: Alan Cox <alan@xxxxxxxxxx>

diff --git a/drivers/char/rtc.c b/drivers/char/rtc.c
index 5f80a9d..3ea201a 100644
--- a/drivers/char/rtc.c
+++ b/drivers/char/rtc.c
@@ -77,9 +77,10 @@
#include <linux/wait.h>
#include <linux/bcd.h>
#include <linux/delay.h>
+#include <linux/smp_lock.h>
+#include <linux/uaccess.h>

#include <asm/current.h>
-#include <asm/uaccess.h>
#include <asm/system.h>

#ifdef CONFIG_X86
@@ -143,8 +144,7 @@ static DEFINE_TIMER(rtc_irq_timer, rtc_dropped_irq, 0, 0);
static ssize_t rtc_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos);

-static int rtc_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg);
+static int rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg);

#ifdef RTC_IRQ
static unsigned int rtc_poll(struct file *file, poll_table *wait);
@@ -717,10 +717,13 @@ static int rtc_do_ioctl(unsigned int cmd, unsigned long arg, int kernel)
&wtime, sizeof wtime) ? -EFAULT : 0;
}

-static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
- unsigned long arg)
+static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
- return rtc_do_ioctl(cmd, arg, 0);
+ long ret;
+ lock_kernel();
+ ret = rtc_do_ioctl(cmd, arg, 0);
+ unlock_kernel();
+ return ret;
}

/*
@@ -910,7 +913,7 @@ static const struct file_operations rtc_fops = {
#ifdef RTC_IRQ
.poll = rtc_poll,
#endif
- .ioctl = rtc_ioctl,
+ .unlocked_ioctl = rtc_ioctl,
.open = rtc_open,
.release = rtc_release,
.fasync = rtc_fasync,
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/