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authorArnd Bergmann <arnd@arndb.de>2010-06-02 14:28:52 +0200
committerArnd Bergmann <arnd@arndb.de>2010-10-05 15:01:04 +0200
commit613655fa39ff6957754fa8ceb8559980920eb8ee (patch)
treead19600cb81207b24188683d7fc4ae88013339d1 /drivers/sbus
parent609146fdb319cebce93be550938ab852f7bade90 (diff)
downloadvexpress-lsk-613655fa39ff6957754fa8ceb8559980920eb8ee.tar.gz
drivers: 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. These drivers do not seem to be under active maintainance from my brief investigation. Apologies to those maintainers that I have missed. 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>
Diffstat (limited to 'drivers/sbus')
-rw-r--r--drivers/sbus/char/jsflash.c24
1 files changed, 13 insertions, 11 deletions
diff --git a/drivers/sbus/char/jsflash.c b/drivers/sbus/char/jsflash.c
index 4942050dc5b..13f48e28a1e 100644
--- a/drivers/sbus/char/jsflash.c
+++ b/drivers/sbus/char/jsflash.c
@@ -27,7 +27,7 @@
*/
#include <linux/module.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
@@ -68,6 +68,8 @@
#define JSF_PART_BITS 2 /* 2 bits of minors to cover JSF_NPART */
#define JSF_PART_MASK 0x3 /* 2 bits mask */
+static DEFINE_MUTEX(jsf_mutex);
+
/*
* Access functions.
* We could ioremap(), but it's easier this way.
@@ -225,7 +227,7 @@ static loff_t jsf_lseek(struct file * file, loff_t offset, int orig)
{
loff_t ret;
- lock_kernel();
+ mutex_lock(&jsf_mutex);
switch (orig) {
case 0:
file->f_pos = offset;
@@ -238,7 +240,7 @@ static loff_t jsf_lseek(struct file * file, loff_t offset, int orig)
default:
ret = -EINVAL;
}
- unlock_kernel();
+ mutex_unlock(&jsf_mutex);
return ret;
}
@@ -384,18 +386,18 @@ static int jsf_ioctl_program(void __user *arg)
static long jsf_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
{
- lock_kernel();
+ mutex_lock(&jsf_mutex);
int error = -ENOTTY;
void __user *argp = (void __user *)arg;
if (!capable(CAP_SYS_ADMIN)) {
- unlock_kernel();
+ mutex_unlock(&jsf_mutex);
return -EPERM;
}
switch (cmd) {
case JSFLASH_IDENT:
if (copy_to_user(argp, &jsf0.id, JSFIDSZ)) {
- unlock_kernel();
+ mutex_unlock(&jsf_mutex);
return -EFAULT;
}
break;
@@ -407,7 +409,7 @@ static long jsf_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
break;
}
- unlock_kernel();
+ mutex_unlock(&jsf_mutex);
return error;
}
@@ -418,17 +420,17 @@ static int jsf_mmap(struct file * file, struct vm_area_struct * vma)
static int jsf_open(struct inode * inode, struct file * filp)
{
- lock_kernel();
+ mutex_lock(&jsf_mutex);
if (jsf0.base == 0) {
- unlock_kernel();
+ mutex_unlock(&jsf_mutex);
return -ENXIO;
}
if (test_and_set_bit(0, (void *)&jsf0.busy) != 0) {
- unlock_kernel();
+ mutex_unlock(&jsf_mutex);
return -EBUSY;
}
- unlock_kernel();
+ mutex_unlock(&jsf_mutex);
return 0; /* XXX What security? */
}