[S390] qdio: Use kstrtoul_from_user

This patch replaces the code for getting an unsigned long from a
userspace buffer by a simple call to kstroul_from_user.
This makes it easier to read and less error prone.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Acked-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

diff --git a/drivers/s390/cio/qdio_debug.c b/drivers/s390/cio/qdio_debug.c
index f8b03a6..0e615cb 100644 (file)
--- a/drivers/s390/cio/qdio_debug.c
+++ b/drivers/s390/cio/qdio_debug.c
@@ -188,19 +188,13 @@ static ssize_t qperf_seq_write(struct file *file, const char __user *ubuf,
        struct qdio_irq *irq_ptr = seq->private;
        struct qdio_q *q;
        unsigned long val;
-       char buf[8];
        int ret, i;
 
        if (!irq_ptr)
                return 0;
-       if (count >= sizeof(buf))
-               return -EINVAL;
-       if (copy_from_user(&buf, ubuf, count))
-               return -EFAULT;
-       buf[count] = 0;
-
-       ret = strict_strtoul(buf, 10, &val);
-       if (ret < 0)
+
+       ret = kstrtoul_from_user(ubuf, count, 10, &val);
+       if (ret)
                return ret;
 
        switch (val) {