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Commit 925ce689 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Greg Kroah-Hartman
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USB: 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>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 7c7e2d00

drivers/usb/gadget/printer.c

+4 −3
Original line number Diff line number Diff line
@@ -25,7 +25,7 @@ 
#include <linux/ioport.h>

#include <linux/sched.h>

#include <linux/slab.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/errno.h>

#include <linux/init.h>

#include <linux/timer.h>
@@ -70,6 +70,7 @@ 
#define DRIVER_DESC		"Printer Gadget"

#define DRIVER_VERSION		"2007 OCT 06"



static DEFINE_MUTEX(printer_mutex);

static const char shortname [] = "printer";

static const char driver_desc [] = DRIVER_DESC;
@@ -476,7 +477,7 @@ printer_open(struct inode *inode, struct file *fd) 
	unsigned long		flags;

	int			ret = -EBUSY;



	lock_kernel();

	mutex_lock(&printer_mutex);

	dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);



	spin_lock_irqsave(&dev->lock, flags);
@@ -492,7 +493,7 @@ printer_open(struct inode *inode, struct file *fd) 
	spin_unlock_irqrestore(&dev->lock, flags);



	DBG(dev, "printer_open returned %x\n", ret);

	unlock_kernel();

	mutex_unlock(&printer_mutex);

	return ret;

}

drivers/usb/misc/iowarrior.c

+8 −7
Original line number Diff line number Diff line
@@ -18,7 +18,7 @@ 
#include <linux/init.h>

#include <linux/slab.h>

#include <linux/sched.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/poll.h>

#include <linux/usb/iowarrior.h>
@@ -61,6 +61,7 @@ MODULE_DESCRIPTION(DRIVER_DESC); 
MODULE_LICENSE("GPL");



/* Module parameters */

static DEFINE_MUTEX(iowarrior_mutex);

static int debug = 0;

module_param(debug, bool, 0644);

MODULE_PARM_DESC(debug, "debug=1 enables debugging messages");
@@ -493,7 +494,7 @@ static long iowarrior_ioctl(struct file *file, unsigned int cmd, 
		return -ENOMEM;



	/* lock this object */

	lock_kernel();

	mutex_lock(&iowarrior_mutex);

	mutex_lock(&dev->mutex);



	/* verify that the device wasn't unplugged */
@@ -585,7 +586,7 @@ static long iowarrior_ioctl(struct file *file, unsigned int cmd, 
error_out:

	/* unlock the device */

	mutex_unlock(&dev->mutex);

	unlock_kernel();

	mutex_unlock(&iowarrior_mutex);

	kfree(buffer);

	return retval;

}
@@ -602,12 +603,12 @@ static int iowarrior_open(struct inode *inode, struct file *file) 


	dbg("%s", __func__);



	lock_kernel();

	mutex_lock(&iowarrior_mutex);

	subminor = iminor(inode);



	interface = usb_find_interface(&iowarrior_driver, subminor);

	if (!interface) {

		unlock_kernel();

		mutex_unlock(&iowarrior_mutex);

		err("%s - error, can't find device for minor %d", __func__,

		    subminor);

		return -ENODEV;
@@ -617,7 +618,7 @@ static int iowarrior_open(struct inode *inode, struct file *file) 
	dev = usb_get_intfdata(interface);

	if (!dev) {

		mutex_unlock(&iowarrior_open_disc_lock);

		unlock_kernel();

		mutex_unlock(&iowarrior_mutex);

		return -ENODEV;

	}
@@ -644,7 +645,7 @@ static int iowarrior_open(struct inode *inode, struct file *file) 


out:

	mutex_unlock(&dev->mutex);

	unlock_kernel();

	mutex_unlock(&iowarrior_mutex);

	return retval;

}

drivers/usb/misc/rio500.c

+8 −7
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ 
#include <linux/kernel.h>

#include <linux/signal.h>

#include <linux/sched.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/errno.h>

#include <linux/random.h>

#include <linux/poll.h>
@@ -72,6 +72,7 @@ struct rio_usb_data { 
	struct mutex lock;          /* general race avoidance */

};



static DEFINE_MUTEX(rio500_mutex);

static struct rio_usb_data rio_instance;



static int open_rio(struct inode *inode, struct file *file)
@@ -79,12 +80,12 @@ static int open_rio(struct inode *inode, struct file *file) 
	struct rio_usb_data *rio = &rio_instance;



	/* against disconnect() */

	lock_kernel();

	mutex_lock(&rio500_mutex);

	mutex_lock(&(rio->lock));



	if (rio->isopen || !rio->present) {

		mutex_unlock(&(rio->lock));

		unlock_kernel();

		mutex_unlock(&rio500_mutex);

		return -EBUSY;

	}

	rio->isopen = 1;
@@ -94,7 +95,7 @@ static int open_rio(struct inode *inode, struct file *file) 
	mutex_unlock(&(rio->lock));



	dev_info(&rio->rio_dev->dev, "Rio opened.\n");

	unlock_kernel();

	mutex_unlock(&rio500_mutex);



	return 0;

}
@@ -491,7 +492,7 @@ static void disconnect_rio(struct usb_interface *intf) 
	struct rio_usb_data *rio = usb_get_intfdata (intf);



	usb_set_intfdata (intf, NULL);

	lock_kernel();

	mutex_lock(&rio500_mutex);

	if (rio) {

		usb_deregister_dev(intf, &usb_rio_class);
@@ -501,7 +502,7 @@ static void disconnect_rio(struct usb_interface *intf) 
			/* better let it finish - the release will do whats needed */

			rio->rio_dev = NULL;

			mutex_unlock(&(rio->lock));

			unlock_kernel();

			mutex_unlock(&rio500_mutex);

			return;

		}

		kfree(rio->ibuf);
@@ -512,7 +513,7 @@ static void disconnect_rio(struct usb_interface *intf) 
		rio->present = 0;

		mutex_unlock(&(rio->lock));

	}

	unlock_kernel();

	mutex_unlock(&rio500_mutex);

}



static const struct usb_device_id rio_table[] = {

drivers/usb/misc/usblcd.c

+8 −8
Original line number Diff line number Diff line
@@ -16,7 +16,6 @@ 
#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/slab.h>

#include <linux/smp_lock.h>

#include <linux/errno.h>

#include <linux/mutex.h>

#include <asm/uaccess.h>
@@ -30,6 +29,7 @@ 
#define IOCTL_GET_DRV_VERSION	2





static DEFINE_MUTEX(lcd_mutex);

static const struct usb_device_id id_table[] = {

	{ .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },

	{ },
@@ -74,12 +74,12 @@ static int lcd_open(struct inode *inode, struct file *file) 
	struct usb_interface *interface;

	int subminor, r;



	lock_kernel();

	mutex_lock(&lcd_mutex);

	subminor = iminor(inode);



	interface = usb_find_interface(&lcd_driver, subminor);

	if (!interface) {

		unlock_kernel();

		mutex_unlock(&lcd_mutex);

		err ("USBLCD: %s - error, can't find device for minor %d",

		     __func__, subminor);

		return -ENODEV;
@@ -89,7 +89,7 @@ static int lcd_open(struct inode *inode, struct file *file) 
	dev = usb_get_intfdata(interface);

	if (!dev) {

		mutex_unlock(&open_disc_mutex);

		unlock_kernel();

		mutex_unlock(&lcd_mutex);

		return -ENODEV;

	}
@@ -101,13 +101,13 @@ static int lcd_open(struct inode *inode, struct file *file) 
	r = usb_autopm_get_interface(interface);

	if (r < 0) {

		kref_put(&dev->kref, lcd_delete);

		unlock_kernel();

		mutex_unlock(&lcd_mutex);

		return r;

	}



	/* save our object in the file's private structure */

	file->private_data = dev;

	unlock_kernel();

	mutex_unlock(&lcd_mutex);



	return 0;

}
@@ -164,14 +164,14 @@ static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 
	

	switch (cmd) {

	case IOCTL_GET_HARD_VERSION:

		lock_kernel();

		mutex_lock(&lcd_mutex);

		bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);

		sprintf(buf,"%1d%1d.%1d%1d",

			(bcdDevice & 0xF000)>>12,

			(bcdDevice & 0xF00)>>8,

			(bcdDevice & 0xF0)>>4,

			(bcdDevice & 0xF));

		unlock_kernel();

		mutex_unlock(&lcd_mutex);

		if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)

			return -EFAULT;

		break;