scsi: 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: Arnd Bergmann <arnd@arndb.de>
Cc: linux-scsi@vger.kernel.org
Cc: "James E.J. Bottomley" <James.Bottomley@suse.de>
diff --git a/drivers/message/i2o/i2o_config.c b/drivers/message/i2o/i2o_config.c
index 068ba07..7d3cc57 100644
--- a/drivers/message/i2o/i2o_config.c
+++ b/drivers/message/i2o/i2o_config.c
@@ -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>
@@ -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;
@@ -741,7 +742,7 @@
unsigned long arg)
{
int ret;
- lock_kernel();
+ mutex_lock(&i2o_cfg_mutex);
switch (cmd) {
case I2OGETIOPS:
ret = i2o_cfg_ioctl(file, cmd, arg);
@@ -753,7 +754,7 @@
ret = -ENOIOCTLCMD;
break;
}
- unlock_kernel();
+ mutex_unlock(&i2o_cfg_mutex);
return ret;
}
@@ -981,7 +982,7 @@
{
int ret;
- lock_kernel();
+ mutex_lock(&i2o_cfg_mutex);
switch (cmd) {
case I2OGETIOPS:
ret = i2o_cfg_getiops(arg);
@@ -1037,7 +1038,7 @@
osm_debug("unknown ioctl called!\n");
ret = -EINVAL;
}
- unlock_kernel();
+ mutex_unlock(&i2o_cfg_mutex);
return ret;
}
@@ -1051,7 +1052,7 @@
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;
@@ -1065,7 +1066,7 @@
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;
}
@@ -1076,14 +1077,14 @@
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;
}
@@ -1093,7 +1094,7 @@
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) {
@@ -1103,7 +1104,7 @@
}
}
spin_unlock_irqrestore(&i2o_config_lock, flags);
- unlock_kernel();
+ mutex_unlock(&i2o_cfg_mutex);
return 0;
}