cris: autoconvert trivial BKL users to private mutex

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>

2 files changed, 0 insertions, 4 deletions

diff --git a/arch/cris/arch-v10/drivers/eeprom.c b/arch/cris/arch-v10/drivers/eeprom.c
index c340550..5047a33 100644
--- a/arch/cris/arch-v10/drivers/eeprom.c
+++ b/arch/cris/arch-v10/drivers/eeprom.c
@@ -28,7 +28,6 @@
 #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"
@@ -376,7 +375,6 @@ int __init eeprom_init(void)
 /* Opens the device. */
 static int eeprom_open(struct inode * inode, struct file * file)
 {
-  cycle_kernel_lock();
   if(iminor(inode) != EEPROM_MINOR_NR)
      return -ENXIO;
   if(imajor(inode) != EEPROM_MAJOR_NR)
diff --git a/arch/cris/arch-v10/drivers/i2c.c b/arch/cris/arch-v10/drivers/i2c.c
index 399e089..54e2e1a 100644
--- a/arch/cris/arch-v10/drivers/i2c.c
+++ b/arch/cris/arch-v10/drivers/i2c.c
@@ -14,7 +14,6 @@
 
 #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>
@@ -566,7 +565,6 @@ i2c_readreg(unsigned char theSlave, unsigned char theReg)
 static int
 i2c_open(struct inode *inode, struct file *filp)
 {
-	cycle_kernel_lock();
 	return 0;
 }