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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/char/snsc.c
parent609146fdb319cebce93be550938ab852f7bade90 (diff)
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/char/snsc.c')
-rw-r--r--drivers/char/snsc.c9
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/char/snsc.c b/drivers/char/snsc.c
index 32b74de18f5f..208e25731dfe 100644
--- a/drivers/char/snsc.c
+++ b/drivers/char/snsc.c
@@ -21,7 +21,7 @@
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
#include <asm/sn/io.h>
#include <asm/sn/sn_sal.h>
#include <asm/sn/module.h>
@@ -34,6 +34,7 @@
#define SCDRV_BUFSZ 2048
#define SCDRV_TIMEOUT 1000
+static DEFINE_MUTEX(scdrv_mutex);
static irqreturn_t
scdrv_interrupt(int irq, void *subch_data)
{
@@ -105,7 +106,7 @@ scdrv_open(struct inode *inode, struct file *file)
file->private_data = sd;
/* hook this subchannel up to the system controller interrupt */
- lock_kernel();
+ mutex_lock(&scdrv_mutex);
rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt,
IRQF_SHARED | IRQF_DISABLED,
SYSCTL_BASENAME, sd);
@@ -113,10 +114,10 @@ scdrv_open(struct inode *inode, struct file *file)
ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);
kfree(sd);
printk("%s: irq request failed (%d)\n", __func__, rv);
- unlock_kernel();
+ mutex_unlock(&scdrv_mutex);
return -EBUSY;
}
- unlock_kernel();
+ mutex_unlock(&scdrv_mutex);
return 0;
}