All these files use the big kernel lock in a trivial
way to serialize their private file operations,
typically resulting from an earlier semi-automatic
pushdown from VFS.
None of these drivers appears to want to lock against
other code, and they all use the BKL as the top-level
lock in their file operations, meaning that there
is no lock-order inversion problem.
Consequently, we can remove the BKL completely,
replacing it with a per-file mutex in every case.
Using a scripted approach means we can avoid
typos.
file=$1
name=$2
if grep -q lock_kernel ${file} ; then
if grep -q 'include.*linux.mutex.h' ${file} ; then
sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
else
sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
fi
sed -i ${file} \
-e "/^#include.*linux.mutex.h/,$ {
1,/^\(static\|int\|long\)/ {
/^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);
} }" \
-e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
-e '/[ ]*cycle_kernel_lock();/d'
else
sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \
-e '/cycle_kernel_lock()/d'
fi
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
-#include <linux/smp_lock.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
#include "i2c.h"
#include <linux/wait.h>
#include <asm/uaccess.h>
#include "i2c.h"
/* Opens the device. */
static int eeprom_open(struct inode * inode, struct file * file)
{
/* Opens the device. */
static int eeprom_open(struct inode * inode, struct file * file)
{
if(iminor(inode) != EEPROM_MINOR_NR)
return -ENXIO;
if(imajor(inode) != EEPROM_MAJOR_NR)
if(iminor(inode) != EEPROM_MINOR_NR)
return -ENXIO;
if(imajor(inode) != EEPROM_MAJOR_NR)
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/sched.h>
-#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/fs.h>
static int
i2c_open(struct inode *inode, struct file *filp)
{
static int
i2c_open(struct inode *inode, struct file *filp)
{
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/mm.h>
-#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
if (p != CRYPTOCOP_MINOR) return -EINVAL;
filp->private_data = NULL;
if (p != CRYPTOCOP_MINOR) return -EINVAL;
filp->private_data = NULL;
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/init.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <asm/etraxi2c.h>
#include <asm/etraxi2c.h>
#define D(x)
#define I2C_MAJOR 123 /* LOCAL/EXPERIMENTAL */
#define D(x)
#define I2C_MAJOR 123 /* LOCAL/EXPERIMENTAL */
+static DEFINE_MUTEX(i2c_mutex);
static const char i2c_name[] = "i2c";
#define CLOCK_LOW_TIME 8
static const char i2c_name[] = "i2c";
#define CLOCK_LOW_TIME 8
static int
i2c_open(struct inode *inode, struct file *filp)
{
static int
i2c_open(struct inode *inode, struct file *filp)
{
I2C_ARGREG(arg),
I2C_ARGVALUE(arg)));
I2C_ARGREG(arg),
I2C_ARGVALUE(arg)));
+ mutex_lock(&i2c_mutex);
ret = i2c_writereg(I2C_ARGSLAVE(arg),
I2C_ARGREG(arg),
I2C_ARGVALUE(arg));
ret = i2c_writereg(I2C_ARGSLAVE(arg),
I2C_ARGREG(arg),
I2C_ARGVALUE(arg));
+ mutex_unlock(&i2c_mutex);
return ret;
case I2C_READREG:
return ret;
case I2C_READREG:
D(printk("i2cr %d %d ",
I2C_ARGSLAVE(arg),
I2C_ARGREG(arg)));
D(printk("i2cr %d %d ",
I2C_ARGSLAVE(arg),
I2C_ARGREG(arg)));
+ mutex_lock(&i2c_mutex);
val = i2c_readreg(I2C_ARGSLAVE(arg), I2C_ARGREG(arg));
val = i2c_readreg(I2C_ARGSLAVE(arg), I2C_ARGREG(arg));
+ mutex_unlock(&i2c_mutex);
D(printk("= %d\n", val));
return val;
}
D(printk("= %d\n", val));
return val;
}