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Commit 609146fd authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

ipmi: 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>
Acked-by: default avatarCorey Minyard <cminyard@mvista.com>
Cc: openipmi-developer@lists.sourceforge.net
parent d851b6e0

drivers/char/ipmi/ipmi_devintf.c

+7 −7
Original line number Original line Diff line number Diff line
@@ -44,7 +44,6 @@ 
#include <linux/init.h>

#include <linux/init.h>

#include <linux/device.h>

#include <linux/device.h>

#include <linux/compat.h>

#include <linux/compat.h>

#include <linux/smp_lock.h>





struct ipmi_file_private

struct ipmi_file_private

{

{
@@ -59,6 +58,7 @@ struct ipmi_file_private 
	unsigned int         default_retry_time_ms;

	unsigned int         default_retry_time_ms;

};

};





static DEFINE_MUTEX(ipmi_mutex);

static void file_receive_handler(struct ipmi_recv_msg *msg,

static void file_receive_handler(struct ipmi_recv_msg *msg,

				 void                 *handler_data)

				 void                 *handler_data)

{

{
@@ -102,9 +102,9 @@ static int ipmi_fasync(int fd, struct file *file, int on) 
	struct ipmi_file_private *priv = file->private_data;

	struct ipmi_file_private *priv = file->private_data;

	int                      result;

	int                      result;





	lock_kernel(); /* could race against open() otherwise */

	mutex_lock(&ipmi_mutex); /* could race against open() otherwise */

	result = fasync_helper(fd, file, on, &priv->fasync_queue);

	result = fasync_helper(fd, file, on, &priv->fasync_queue);

	unlock_kernel();

	mutex_unlock(&ipmi_mutex);





	return (result);

	return (result);

}

}
@@ -125,7 +125,7 @@ static int ipmi_open(struct inode *inode, struct file *file) 
	if (!priv)

	if (!priv)

		return -ENOMEM;

		return -ENOMEM;





	lock_kernel();

	mutex_lock(&ipmi_mutex);

	priv->file = file;

	priv->file = file;





	rv = ipmi_create_user(if_num,

	rv = ipmi_create_user(if_num,
@@ -150,7 +150,7 @@ static int ipmi_open(struct inode *inode, struct file *file) 
	priv->default_retry_time_ms = 0;

	priv->default_retry_time_ms = 0;





out:

out:

	unlock_kernel();

	mutex_unlock(&ipmi_mutex);

	return rv;

	return rv;

}

}
@@ -639,9 +639,9 @@ static long ipmi_unlocked_ioctl(struct file *file, 
{

{

	int ret;

	int ret;





	lock_kernel();

	mutex_lock(&ipmi_mutex);

	ret = ipmi_ioctl(file, cmd, data);

	ret = ipmi_ioctl(file, cmd, data);

	unlock_kernel();

	mutex_unlock(&ipmi_mutex);





	return ret;

	return ret;

}

}

drivers/char/ipmi/ipmi_watchdog.c

+4 −4
Original line number Original line Diff line number Diff line
@@ -35,7 +35,7 @@ 
#include <linux/moduleparam.h>

#include <linux/moduleparam.h>

#include <linux/ipmi.h>

#include <linux/ipmi.h>

#include <linux/ipmi_smi.h>

#include <linux/ipmi_smi.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/watchdog.h>

#include <linux/watchdog.h>

#include <linux/miscdevice.h>

#include <linux/miscdevice.h>

#include <linux/init.h>

#include <linux/init.h>
@@ -149,6 +149,7 @@ 
#define	WDIOC_GET_PRETIMEOUT     _IOW(WATCHDOG_IOCTL_BASE, 22, int)

#define	WDIOC_GET_PRETIMEOUT     _IOW(WATCHDOG_IOCTL_BASE, 22, int)

#endif

#endif





static DEFINE_MUTEX(ipmi_watchdog_mutex);

static int nowayout = WATCHDOG_NOWAYOUT;

static int nowayout = WATCHDOG_NOWAYOUT;





static ipmi_user_t watchdog_user;

static ipmi_user_t watchdog_user;
@@ -748,9 +749,9 @@ static long ipmi_unlocked_ioctl(struct file *file, 
{

{

	int ret;

	int ret;





	lock_kernel();

	mutex_lock(&ipmi_watchdog_mutex);

	ret = ipmi_ioctl(file, cmd, arg);

	ret = ipmi_ioctl(file, cmd, arg);

	unlock_kernel();

	mutex_unlock(&ipmi_watchdog_mutex);





	return ret;

	return ret;

}

}
@@ -844,7 +845,6 @@ static int ipmi_open(struct inode *ino, struct file *filep) 
		if (test_and_set_bit(0, &ipmi_wdog_open))

		if (test_and_set_bit(0, &ipmi_wdog_open))

			return -EBUSY;

			return -EBUSY;





		cycle_kernel_lock();





		/*

		/*

		 * Don't start the timer now, let it start on the

		 * Don't start the timer now, let it start on the