sparc: Remove BKL from apc

commit ab772027 (sparc: arch/sparc/kernel/apc.c to unlocked_ioctl)
added lock/unlock_kernel() to the apc ioctl code.

The code needs no serialization at all. Neither put/get_user nor the
read/write access to the sbus devices require it. Remove BKL.

cycle_kernel_lock() was added during the big BKL pushdown. It should
ensure the serializiation against driver init code. In this case there
is nothing to serialize. Remove it as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 27 deletions

diff --git a/arch/sparc/kernel/apc.c b/arch/sparc/kernel/apc.c
index 9c115823c4b5..71ec90b9e316 100644
--- a/arch/sparc/kernel/apc.c
+++ b/arch/sparc/kernel/apc.c
@@ -10,7 +10,6 @@
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/miscdevice.h>
-#include <linux/smp_lock.h>
 #include <linux/pm.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
@@ -76,7 +75,6 @@ static inline void apc_free(struct of_device *op)
 
 static int apc_open(struct inode *inode, struct file *f)
 {
-        cycle_kernel_lock();
         return 0;
 }
 
@@ -87,61 +85,46 @@ static int apc_release(struct inode *inode, struct file *f)
 
 static long apc_ioctl(struct file *f, unsigned int cmd, unsigned long __arg)
 {
-        __u8 inarg, __user *arg;
-
-        arg = (__u8 __user *) __arg;
-
-        lock_kernel();
+        __u8 inarg, __user *arg = (__u8 __user *) __arg;
 
         switch (cmd) {
         case APCIOCGFANCTL:
-                if (put_user(apc_readb(APC_FANCTL_REG) & APC_REGMASK, arg)) {
-                        unlock_kernel();
+                if (put_user(apc_readb(APC_FANCTL_REG) & APC_REGMASK, arg))
                         return -EFAULT;
-                }
                 break;
 
         case APCIOCGCPWR:
-                if (put_user(apc_readb(APC_CPOWER_REG) & APC_REGMASK, arg)) {
-                        unlock_kernel();
+                if (put_user(apc_readb(APC_CPOWER_REG) & APC_REGMASK, arg))
                         return -EFAULT;
-                }
                 break;
 
         case APCIOCGBPORT:
-                if (put_user(apc_readb(APC_BPORT_REG) & APC_BPMASK, arg)) {
-                        unlock_kernel();
+                if (put_user(apc_readb(APC_BPORT_REG) & APC_BPMASK, arg))
                         return -EFAULT;
-                }
                 break;
 
         case APCIOCSFANCTL:
-                if (get_user(inarg, arg)) {
-                        unlock_kernel();
+                if (get_user(inarg, arg))
                         return -EFAULT;
-                }
                 apc_writeb(inarg & APC_REGMASK, APC_FANCTL_REG);
                 break;
+
         case APCIOCSCPWR:
-                if (get_user(inarg, arg)) {
-                        unlock_kernel();
+                if (get_user(inarg, arg))
                         return -EFAULT;
-                }
                 apc_writeb(inarg & APC_REGMASK, APC_CPOWER_REG);
                 break;
+
         case APCIOCSBPORT:
-                if (get_user(inarg, arg)) {
-                        unlock_kernel();
+                if (get_user(inarg, arg))
                         return -EFAULT;
-                }
                 apc_writeb(inarg & APC_BPMASK, APC_BPORT_REG);
                 break;
+
         default:
-                unlock_kernel();
                 return -EINVAL;
         };
 
-        unlock_kernel();
         return 0;
 }