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scsi: autoconvert trivial BKL users to private mutex
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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 <[email protected]>
Cc: [email protected]
Cc: "James E.J. Bottomley" <[email protected]>
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@arndb
arndb committed Sep 15, 2010
1 parent 49553c2 commit c45d15d
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Showing 16 changed files with 86 additions and 85 deletions.
15 changes: 8 additions & 7 deletions drivers/message/fusion/mptctl.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -54,7 +54,7 @@
#include <linux/pci.h>
#include <linux/delay.h> /* for mdelay */
#include <linux/miscdevice.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include <linux/compat.h>

#include <asm/io.h>
Expand Down Expand Up @@ -83,6 +83,7 @@ MODULE_VERSION(my_VERSION);

/*=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/

static DEFINE_MUTEX(mpctl_mutex);
static u8 mptctl_id = MPT_MAX_PROTOCOL_DRIVERS;
static u8 mptctl_taskmgmt_id = MPT_MAX_PROTOCOL_DRIVERS;

Expand Down Expand Up @@ -601,12 +602,12 @@ mptctl_fasync(int fd, struct file *filep, int mode)
MPT_ADAPTER *ioc;
int ret;

lock_kernel();
mutex_lock(&mpctl_mutex);
list_for_each_entry(ioc, &ioc_list, list)
ioc->aen_event_read_flag=0;

ret = fasync_helper(fd, filep, mode, &async_queue);
unlock_kernel();
mutex_unlock(&mpctl_mutex);
return ret;
}

Expand Down Expand Up @@ -698,9 +699,9 @@ static long
mptctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
long ret;
lock_kernel();
mutex_lock(&mpctl_mutex);
ret = __mptctl_ioctl(file, cmd, arg);
unlock_kernel();
mutex_unlock(&mpctl_mutex);
return ret;
}

Expand Down Expand Up @@ -2926,7 +2927,7 @@ compat_mpt_command(struct file *filp, unsigned int cmd,
static long compat_mpctl_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
{
long ret;
lock_kernel();
mutex_lock(&mpctl_mutex);
switch (cmd) {
case MPTIOCINFO:
case MPTIOCINFO1:
Expand All @@ -2951,7 +2952,7 @@ static long compat_mpctl_ioctl(struct file *f, unsigned int cmd, unsigned long a
ret = -ENOIOCTLCMD;
break;
}
unlock_kernel();
mutex_unlock(&mpctl_mutex);
return ret;
}

Expand Down
23 changes: 12 additions & 11 deletions drivers/message/i2o/i2o_config.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -31,7 +31,7 @@
*/

#include <linux/miscdevice.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include <linux/compat.h>
#include <linux/slab.h>

Expand All @@ -41,6 +41,7 @@

#define SG_TABLESIZE 30

static DEFINE_MUTEX(i2o_cfg_mutex);
static long i2o_cfg_ioctl(struct file *, unsigned int, unsigned long);

static spinlock_t i2o_config_lock;
Expand Down Expand Up @@ -741,7 +742,7 @@ static long i2o_cfg_compat_ioctl(struct file *file, unsigned cmd,
unsigned long arg)
{
int ret;
lock_kernel();
mutex_lock(&i2o_cfg_mutex);
switch (cmd) {
case I2OGETIOPS:
ret = i2o_cfg_ioctl(file, cmd, arg);
Expand All @@ -753,7 +754,7 @@ static long i2o_cfg_compat_ioctl(struct file *file, unsigned cmd,
ret = -ENOIOCTLCMD;
break;
}
unlock_kernel();
mutex_unlock(&i2o_cfg_mutex);
return ret;
}

Expand Down Expand Up @@ -981,7 +982,7 @@ static long i2o_cfg_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
{
int ret;

lock_kernel();
mutex_lock(&i2o_cfg_mutex);
switch (cmd) {
case I2OGETIOPS:
ret = i2o_cfg_getiops(arg);
Expand Down Expand Up @@ -1037,7 +1038,7 @@ static long i2o_cfg_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
osm_debug("unknown ioctl called!\n");
ret = -EINVAL;
}
unlock_kernel();
mutex_unlock(&i2o_cfg_mutex);
return ret;
}

Expand All @@ -1051,7 +1052,7 @@ static int cfg_open(struct inode *inode, struct file *file)
if (!tmp)
return -ENOMEM;

lock_kernel();
mutex_lock(&i2o_cfg_mutex);
file->private_data = (void *)(i2o_cfg_info_id++);
tmp->fp = file;
tmp->fasync = NULL;
Expand All @@ -1065,7 +1066,7 @@ static int cfg_open(struct inode *inode, struct file *file)
spin_lock_irqsave(&i2o_config_lock, flags);
open_files = tmp;
spin_unlock_irqrestore(&i2o_config_lock, flags);
unlock_kernel();
mutex_unlock(&i2o_cfg_mutex);

return 0;
}
Expand All @@ -1076,14 +1077,14 @@ static int cfg_fasync(int fd, struct file *fp, int on)
struct i2o_cfg_info *p;
int ret = -EBADF;

lock_kernel();
mutex_lock(&i2o_cfg_mutex);
for (p = open_files; p; p = p->next)
if (p->q_id == id)
break;

if (p)
ret = fasync_helper(fd, fp, on, &p->fasync);
unlock_kernel();
mutex_unlock(&i2o_cfg_mutex);
return ret;
}

Expand All @@ -1093,7 +1094,7 @@ static int cfg_release(struct inode *inode, struct file *file)
struct i2o_cfg_info *p, **q;
unsigned long flags;

lock_kernel();
mutex_lock(&i2o_cfg_mutex);
spin_lock_irqsave(&i2o_config_lock, flags);
for (q = &open_files; (p = *q) != NULL; q = &p->next) {
if (p->q_id == id) {
Expand All @@ -1103,7 +1104,7 @@ static int cfg_release(struct inode *inode, struct file *file)
}
}
spin_unlock_irqrestore(&i2o_config_lock, flags);
unlock_kernel();
mutex_unlock(&i2o_cfg_mutex);

return 0;
}
Expand Down
7 changes: 3 additions & 4 deletions drivers/scsi/3w-9xxx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -92,7 +92,6 @@
#include <linux/pci.h>
#include <linux/time.h>
#include <linux/mutex.h>
#include <linux/smp_lock.h>
#include <linux/slab.h>
#include <asm/io.h>
#include <asm/irq.h>
Expand All @@ -105,6 +104,7 @@

/* Globals */
#define TW_DRIVER_VERSION "2.26.02.014"
static DEFINE_MUTEX(twa_chrdev_mutex);
static TW_Device_Extension *twa_device_extension_list[TW_MAX_SLOT];
static unsigned int twa_device_extension_count;
static int twa_major = -1;
Expand Down Expand Up @@ -658,7 +658,7 @@ static long twa_chrdev_ioctl(struct file *file, unsigned int cmd, unsigned long
int retval = TW_IOCTL_ERROR_OS_EFAULT;
void __user *argp = (void __user *)arg;

lock_kernel();
mutex_lock(&twa_chrdev_mutex);

/* Only let one of these through at a time */
if (mutex_lock_interruptible(&tw_dev->ioctl_lock)) {
Expand Down Expand Up @@ -879,7 +879,7 @@ static long twa_chrdev_ioctl(struct file *file, unsigned int cmd, unsigned long
out2:
mutex_unlock(&tw_dev->ioctl_lock);
out:
unlock_kernel();
mutex_unlock(&twa_chrdev_mutex);
return retval;
} /* End twa_chrdev_ioctl() */

Expand All @@ -890,7 +890,6 @@ static int twa_chrdev_open(struct inode *inode, struct file *file)
unsigned int minor_number;
int retval = TW_IOCTL_ERROR_OS_ENODEV;

cycle_kernel_lock();
minor_number = iminor(inode);
if (minor_number >= twa_device_extension_count)
goto out;
Expand Down
7 changes: 3 additions & 4 deletions drivers/scsi/3w-sas.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -64,7 +64,6 @@
#include <linux/pci.h>
#include <linux/time.h>
#include <linux/mutex.h>
#include <linux/smp_lock.h>
#include <linux/slab.h>
#include <asm/io.h>
#include <asm/irq.h>
Expand All @@ -77,6 +76,7 @@

/* Globals */
#define TW_DRIVER_VERSION "3.26.02.000"
static DEFINE_MUTEX(twl_chrdev_mutex);
static TW_Device_Extension *twl_device_extension_list[TW_MAX_SLOT];
static unsigned int twl_device_extension_count;
static int twl_major = -1;
Expand Down Expand Up @@ -764,7 +764,7 @@ static long twl_chrdev_ioctl(struct file *file, unsigned int cmd, unsigned long
int retval = -EFAULT;
void __user *argp = (void __user *)arg;

lock_kernel();
mutex_lock(&twl_chrdev_mutex);

/* Only let one of these through at a time */
if (mutex_lock_interruptible(&tw_dev->ioctl_lock)) {
Expand Down Expand Up @@ -861,7 +861,7 @@ static long twl_chrdev_ioctl(struct file *file, unsigned int cmd, unsigned long
out2:
mutex_unlock(&tw_dev->ioctl_lock);
out:
unlock_kernel();
mutex_unlock(&twl_chrdev_mutex);
return retval;
} /* End twl_chrdev_ioctl() */

Expand All @@ -876,7 +876,6 @@ static int twl_chrdev_open(struct inode *inode, struct file *file)
goto out;
}

cycle_kernel_lock();
minor_number = iminor(inode);
if (minor_number >= twl_device_extension_count)
goto out;
Expand Down
9 changes: 4 additions & 5 deletions drivers/scsi/3w-xxxx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -199,7 +199,6 @@

#include <linux/module.h>
#include <linux/reboot.h>
#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/moduleparam.h>
Expand All @@ -221,6 +220,7 @@

/* Globals */
#define TW_DRIVER_VERSION "1.26.02.003"
static DEFINE_MUTEX(tw_mutex);
static TW_Device_Extension *tw_device_extension_list[TW_MAX_SLOT];
static int tw_device_extension_count = 0;
static int twe_major = -1;
Expand Down Expand Up @@ -900,10 +900,10 @@ static long tw_chrdev_ioctl(struct file *file, unsigned int cmd, unsigned long a

dprintk(KERN_WARNING "3w-xxxx: tw_chrdev_ioctl()\n");

lock_kernel();
mutex_lock(&tw_mutex);
/* Only let one of these through at a time */
if (mutex_lock_interruptible(&tw_dev->ioctl_lock)) {
unlock_kernel();
mutex_unlock(&tw_mutex);
return -EINTR;
}

Expand Down Expand Up @@ -1034,7 +1034,7 @@ static long tw_chrdev_ioctl(struct file *file, unsigned int cmd, unsigned long a
dma_free_coherent(&tw_dev->tw_pci_dev->dev, data_buffer_length_adjusted+sizeof(TW_New_Ioctl) - 1, cpu_addr, dma_handle);
out:
mutex_unlock(&tw_dev->ioctl_lock);
unlock_kernel();
mutex_unlock(&tw_mutex);
return retval;
} /* End tw_chrdev_ioctl() */

Expand All @@ -1044,7 +1044,6 @@ static int tw_chrdev_open(struct inode *inode, struct file *file)
{
unsigned int minor_number;

cycle_kernel_lock();
dprintk(KERN_WARNING "3w-xxxx: tw_ioctl_open()\n");

minor_number = iminor(inode);
Expand Down
15 changes: 8 additions & 7 deletions drivers/scsi/aacraid/linit.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -38,7 +38,7 @@
#include <linux/moduleparam.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
#include <linux/delay.h>
Expand Down Expand Up @@ -76,6 +76,7 @@ MODULE_DESCRIPTION("Dell PERC2, 2/Si, 3/Si, 3/Di, "
MODULE_LICENSE("GPL");
MODULE_VERSION(AAC_DRIVER_FULL_VERSION);

static DEFINE_MUTEX(aac_mutex);
static LIST_HEAD(aac_devices);
static int aac_cfg_major = -1;
char aac_driver_version[] = AAC_DRIVER_FULL_VERSION;
Expand Down Expand Up @@ -678,15 +679,15 @@ static int aac_cfg_open(struct inode *inode, struct file *file)
unsigned minor_number = iminor(inode);
int err = -ENODEV;

lock_kernel(); /* BKL pushdown: nothing else protects this list */
mutex_lock(&aac_mutex); /* BKL pushdown: nothing else protects this list */
list_for_each_entry(aac, &aac_devices, entry) {
if (aac->id == minor_number) {
file->private_data = aac;
err = 0;
break;
}
}
unlock_kernel();
mutex_unlock(&aac_mutex);

return err;
}
Expand All @@ -711,9 +712,9 @@ static long aac_cfg_ioctl(struct file *file,
int ret;
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
lock_kernel();
mutex_lock(&aac_mutex);
ret = aac_do_ioctl(file->private_data, cmd, (void __user *)arg);
unlock_kernel();
mutex_unlock(&aac_mutex);

return ret;
}
Expand All @@ -722,7 +723,7 @@ static long aac_cfg_ioctl(struct file *file,
static long aac_compat_do_ioctl(struct aac_dev *dev, unsigned cmd, unsigned long arg)
{
long ret;
lock_kernel();
mutex_lock(&aac_mutex);
switch (cmd) {
case FSACTL_MINIPORT_REV_CHECK:
case FSACTL_SENDFIB:
Expand Down Expand Up @@ -756,7 +757,7 @@ static long aac_compat_do_ioctl(struct aac_dev *dev, unsigned cmd, unsigned long
ret = -ENOIOCTLCMD;
break;
}
unlock_kernel();
mutex_unlock(&aac_mutex);
return ret;
}

Expand Down
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