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authorArnd Bergmann <arnd@arndb.de>2010-07-20 23:36:39 -0700
committerDavid S. Miller <davem@davemloft.net>2010-07-20 23:36:39 -0700
commita3108ca2323dec0f6321c3f7706cdaed51f694ea (patch)
treeae3ef899219893cf3de5d543d4e3dc7027c00212 /drivers/sbus/char/display7seg.c
parentf8324e20f8289dffc646d64366332e05eaacab25 (diff)
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sbus: 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> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/sbus/char/display7seg.c')
-rw-r--r--drivers/sbus/char/display7seg.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/sbus/char/display7seg.c b/drivers/sbus/char/display7seg.c
index 7baf1b644039..4ad4d2c91075 100644
--- a/drivers/sbus/char/display7seg.c
+++ b/drivers/sbus/char/display7seg.c
@@ -13,7 +13,7 @@
#include <linux/miscdevice.h>
#include <linux/ioport.h> /* request_region */
#include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <asm/atomic.h>
@@ -26,6 +26,7 @@
#define DRIVER_NAME "d7s"
#define PFX DRIVER_NAME ": "
+static DEFINE_MUTEX(d7s_mutex);
static int sol_compat = 0; /* Solaris compatibility mode */
/* Solaris compatibility flag -
@@ -74,7 +75,6 @@ static int d7s_open(struct inode *inode, struct file *f)
{
if (D7S_MINOR != iminor(inode))
return -ENODEV;
- cycle_kernel_lock();
atomic_inc(&d7s_users);
return 0;
}
@@ -110,7 +110,7 @@ static long d7s_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
if (D7S_MINOR != iminor(file->f_path.dentry->d_inode))
return -ENODEV;
- lock_kernel();
+ mutex_lock(&d7s_mutex);
switch (cmd) {
case D7SIOCWR:
/* assign device register values we mask-out D7S_FLIP
@@ -151,7 +151,7 @@ static long d7s_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
writeb(regs, p->regs);
break;
};
- unlock_kernel();
+ mutex_unlock(&d7s_mutex);
return error;
}