Commit 613655fa authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

drivers: 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.

These drivers do not seem to be under active
maintainance from my brief investigation. Apologies
to those maintainers that I have missed.

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>
parent 609146fd

drivers/block/paride/pg.c

+4 −3
Original line number Diff line number Diff line
@@ -162,7 +162,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_DLY}; 
#include <linux/pg.h>

#include <linux/device.h>

#include <linux/sched.h>	/* current, TASK_* */

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/jiffies.h>



#include <asm/uaccess.h>
@@ -193,6 +193,7 @@ module_param_array(drive3, int, NULL, 0); 


#define ATAPI_IDENTIFY		0x12



static DEFINE_MUTEX(pg_mutex);

static int pg_open(struct inode *inode, struct file *file);

static int pg_release(struct inode *inode, struct file *file);

static ssize_t pg_read(struct file *filp, char __user *buf,
@@ -518,7 +519,7 @@ static int pg_open(struct inode *inode, struct file *file) 
	struct pg *dev = &devices[unit];

	int ret = 0;



	lock_kernel();

	mutex_lock(&pg_mutex);

	if ((unit >= PG_UNITS) || (!dev->present)) {

		ret = -ENODEV;

		goto out;
@@ -547,7 +548,7 @@ static int pg_open(struct inode *inode, struct file *file) 
	file->private_data = dev;



out:

	unlock_kernel();

	mutex_unlock(&pg_mutex);

	return ret;

}

drivers/block/paride/pt.c

+10 −9
Original line number Diff line number Diff line
@@ -146,7 +146,7 @@ static int (*drives[4])[6] = {&drive0, &drive1, &drive2, &drive3}; 
#include <linux/mtio.h>

#include <linux/device.h>

#include <linux/sched.h>	/* current, TASK_*, schedule_timeout() */

#include <linux/smp_lock.h>

#include <linux/mutex.h>



#include <asm/uaccess.h>
@@ -189,6 +189,7 @@ module_param_array(drive3, int, NULL, 0); 
#define ATAPI_MODE_SENSE	0x1a

#define ATAPI_LOG_SENSE		0x4d



static DEFINE_MUTEX(pt_mutex);

static int pt_open(struct inode *inode, struct file *file);

static long pt_ioctl(struct file *file, unsigned int cmd, unsigned long arg);

static int pt_release(struct inode *inode, struct file *file);
@@ -650,9 +651,9 @@ static int pt_open(struct inode *inode, struct file *file) 
	struct pt_unit *tape = pt + unit;

	int err;



	lock_kernel();

	mutex_lock(&pt_mutex);

	if (unit >= PT_UNITS || (!tape->present)) {

		unlock_kernel();

		mutex_unlock(&pt_mutex);

		return -ENODEV;

	}
@@ -681,12 +682,12 @@ static int pt_open(struct inode *inode, struct file *file) 
	}



	file->private_data = tape;

	unlock_kernel();

	mutex_unlock(&pt_mutex);

	return 0;



out:

	atomic_inc(&tape->available);

	unlock_kernel();

	mutex_unlock(&pt_mutex);

	return err;

}
@@ -704,15 +705,15 @@ static long pt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
		switch (mtop.mt_op) {



		case MTREW:

			lock_kernel();

			mutex_lock(&pt_mutex);

			pt_rewind(tape);

			unlock_kernel();

			mutex_unlock(&pt_mutex);

			return 0;



		case MTWEOF:

			lock_kernel();

			mutex_lock(&pt_mutex);

			pt_write_fm(tape);

			unlock_kernel();

			mutex_unlock(&pt_mutex);

			return 0;



		default:

drivers/char/apm-emulation.c

+6 −5
Original line number Diff line number Diff line
@@ -13,7 +13,7 @@ 
#include <linux/module.h>

#include <linux/poll.h>

#include <linux/slab.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/proc_fs.h>

#include <linux/seq_file.h>

#include <linux/miscdevice.h>
@@ -126,6 +126,7 @@ struct apm_user { 
/*

 * Local variables

 */

static DEFINE_MUTEX(apm_mutex);

static atomic_t suspend_acks_pending = ATOMIC_INIT(0);

static atomic_t userspace_notification_inhibit = ATOMIC_INIT(0);

static int apm_disabled;
@@ -274,7 +275,7 @@ apm_ioctl(struct file *filp, u_int cmd, u_long arg) 
	if (!as->suser || !as->writer)

		return -EPERM;



	lock_kernel();

	mutex_lock(&apm_mutex);

	switch (cmd) {

	case APM_IOC_SUSPEND:

		mutex_lock(&state_lock);
@@ -335,7 +336,7 @@ apm_ioctl(struct file *filp, u_int cmd, u_long arg) 
		mutex_unlock(&state_lock);

		break;

	}

	unlock_kernel();

	mutex_unlock(&apm_mutex);



	return err;

}
@@ -370,7 +371,7 @@ static int apm_open(struct inode * inode, struct file * filp) 
{

	struct apm_user *as;



	lock_kernel();

	mutex_lock(&apm_mutex);

	as = kzalloc(sizeof(*as), GFP_KERNEL);

	if (as) {

		/*
@@ -390,7 +391,7 @@ static int apm_open(struct inode * inode, struct file * filp) 


		filp->private_data = as;

	}

	unlock_kernel();

	mutex_unlock(&apm_mutex);



	return as ? 0 : -ENOMEM;

}

drivers/char/applicom.c

+5 −4
Original line number Diff line number Diff line
@@ -26,7 +26,7 @@ 
#include <linux/sched.h>

#include <linux/slab.h>

#include <linux/errno.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/miscdevice.h>

#include <linux/pci.h>

#include <linux/wait.h>
@@ -60,6 +60,7 @@ 
#define PCI_DEVICE_ID_APPLICOM_PCI2000PFB     0x0003

#endif



static DEFINE_MUTEX(ac_mutex);

static char *applicom_pci_devnames[] = {

	"PCI board",

	"PCI2000IBS / PCI2000CAN",
@@ -707,7 +708,7 @@ static long ac_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
	if (IS_ERR(adgl))

		return PTR_ERR(adgl);



	lock_kernel();	

	mutex_lock(&ac_mutex);	

	IndexCard = adgl->num_card-1;

	 

	if(cmd != 6 && ((IndexCard >= MAX_BOARD) || !apbs[IndexCard].RamIO)) {
@@ -717,7 +718,7 @@ static long ac_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
			warncount--;

		}

		kfree(adgl);

		unlock_kernel();

		mutex_unlock(&ac_mutex);

		return -EINVAL;

	}
@@ -835,7 +836,7 @@ static long ac_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
	}

	Dummy = readb(apbs[IndexCard].RamIO + VERS);

	kfree(adgl);

	unlock_kernel();

	mutex_unlock(&ac_mutex);

	return 0;

}

drivers/char/ds1302.c

+8 −7
Original line number Diff line number Diff line
@@ -20,7 +20,7 @@ 
#include <linux/miscdevice.h>

#include <linux/delay.h>

#include <linux/bcd.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/uaccess.h>

#include <linux/io.h>
@@ -32,6 +32,7 @@ 


#define RTC_MAJOR_NR 121 /* local major, change later */



static DEFINE_MUTEX(rtc_mutex);

static const char ds1302_name[] = "ds1302";



/* Send 8 bits. */
@@ -164,9 +165,9 @@ static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
			struct rtc_time rtc_tm;



			memset(&rtc_tm, 0, sizeof (struct rtc_time));

			lock_kernel();

			mutex_lock(&rtc_mutex);

			get_rtc_time(&rtc_tm);

			unlock_kernel();

			mutex_unlock(&rtc_mutex);

			if (copy_to_user((struct rtc_time*)arg, &rtc_tm, sizeof(struct rtc_time)))

				return -EFAULT;

			return 0;
@@ -218,7 +219,7 @@ static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
			mon = bin2bcd(mon);

			yrs = bin2bcd(yrs);



			lock_kernel();

			mutex_lock(&rtc_mutex);

			local_irq_save(flags);

			CMOS_WRITE(yrs, RTC_YEAR);

			CMOS_WRITE(mon, RTC_MONTH);
@@ -227,7 +228,7 @@ static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
			CMOS_WRITE(min, RTC_MINUTES);

			CMOS_WRITE(sec, RTC_SECONDS);

			local_irq_restore(flags);

			unlock_kernel();

			mutex_unlock(&rtc_mutex);



			/* Notice that at this point, the RTC is updated but

			 * the kernel is still running with the old time.
@@ -247,10 +248,10 @@ static long rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
			if(copy_from_user(&tcs_val, (int*)arg, sizeof(int)))

				return -EFAULT;



			lock_kernel();

			mutex_lock(&rtc_mutex);

			tcs_val = RTC_TCR_PATTERN | (tcs_val & 0x0F);

			ds1302_writereg(RTC_TRICKLECHARGER, tcs_val);

			unlock_kernel();

			mutex_unlock(&rtc_mutex);

			return 0;

		}

		default:

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