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Commit 76a64921 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by David S. Miller
Browse files

isdn: 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: default avatarArnd Bergmann <arnd@arndb.de>
Cc: Karsten Keil <isdn@linux-pingi.de>
Cc: netdev@vger.kernel.org
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d361fd59

drivers/isdn/capi/capi.c

+3 −3
Original line number Diff line number Diff line
@@ -20,7 +20,6 @@ 
#include <linux/signal.h>

#include <linux/mutex.h>

#include <linux/mm.h>

#include <linux/smp_lock.h>

#include <linux/timer.h>

#include <linux/wait.h>

#include <linux/tty.h>
@@ -50,6 +49,7 @@ MODULE_LICENSE("GPL"); 


/* -------- driver information -------------------------------------- */



static DEFINE_MUTEX(capi_mutex);

static struct class *capi_class;

static int capi_major = 68;		/* allocated */
@@ -985,9 +985,9 @@ capi_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
{

	int ret;



	lock_kernel();

	mutex_lock(&capi_mutex);

	ret = capi_ioctl(file, cmd, arg);

	unlock_kernel();

	mutex_unlock(&capi_mutex);



	return ret;

}

drivers/isdn/divert/divert_procfs.c

+4 −3
Original line number Diff line number Diff line
@@ -20,7 +20,7 @@ 
#include <linux/sched.h>

#include <linux/isdnif.h>

#include <net/net_namespace.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include "isdn_divert.h"
@@ -28,6 +28,7 @@ 
/* Variables for interface queue */

/*********************************/

ulong if_used = 0;		/* number of interface users */

static DEFINE_MUTEX(isdn_divert_mutex);

static struct divert_info *divert_info_head = NULL;	/* head of queue */

static struct divert_info *divert_info_tail = NULL;	/* pointer to last entry */

static DEFINE_SPINLOCK(divert_info_lock);/* lock for queue */
@@ -261,9 +262,9 @@ static long isdn_divert_ioctl(struct file *file, uint cmd, ulong arg) 
{

	long ret;



	lock_kernel();

	mutex_lock(&isdn_divert_mutex);

	ret = isdn_divert_ioctl_unlocked(file, cmd, arg);

	unlock_kernel();

	mutex_unlock(&isdn_divert_mutex);



	return ret;

}

drivers/isdn/hardware/eicon/divamnt.c

+4 −3
Original line number Diff line number Diff line
@@ -14,7 +14,7 @@ 
#include <linux/init.h>

#include <linux/kernel.h>

#include <linux/poll.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <asm/uaccess.h>



#include "platform.h"
@@ -22,6 +22,7 @@ 
#include "divasync.h"

#include "debug_if.h"



static DEFINE_MUTEX(maint_mutex);

static char *main_revision = "$Revision: 1.32.6.10 $";



static int major;
@@ -130,7 +131,7 @@ static int maint_open(struct inode *ino, struct file *filep) 
{

	int ret;



	lock_kernel();

	mutex_lock(&maint_mutex);

	/* only one open is allowed, so we test

	   it atomically */

	if (test_and_set_bit(0, &opened))
@@ -139,7 +140,7 @@ static int maint_open(struct inode *ino, struct file *filep) 
		filep->private_data = NULL;

		ret = nonseekable_open(ino, filep);

	}

	unlock_kernel();

	mutex_unlock(&maint_mutex);

	return ret;

}

drivers/isdn/hardware/eicon/divasi.c

+0 −2
Original line number Diff line number Diff line
@@ -18,7 +18,6 @@ 
#include <linux/proc_fs.h>

#include <linux/skbuff.h>

#include <linux/seq_file.h>

#include <linux/smp_lock.h>

#include <asm/uaccess.h>



#include "platform.h"
@@ -402,7 +401,6 @@ static unsigned int um_idi_poll(struct file *file, poll_table * wait) 


static int um_idi_open(struct inode *inode, struct file *file)

{

	cycle_kernel_lock();

	return (0);

}

drivers/isdn/hardware/eicon/divasmain.c

+0 −2
Original line number Diff line number Diff line
@@ -21,7 +21,6 @@ 
#include <linux/list.h>

#include <linux/poll.h>

#include <linux/kmod.h>

#include <linux/smp_lock.h>



#include "platform.h"

#undef ID_MASK
@@ -581,7 +580,6 @@ xdi_copy_from_user(void *os_handle, void *dst, const void __user *src, int lengt 
 */

static int divas_open(struct inode *inode, struct file *file)

{

	cycle_kernel_lock();

	return (0);

}