[S390] s390/cio: use memory_read_from_buffer()

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 2 insertions, 9 deletions

diff --git a/drivers/s390/cio/chp.c b/drivers/s390/cio/chp.c
index 8644c80a2056..d58dc9f15b72 100644
--- a/drivers/s390/cio/chp.c
+++ b/drivers/s390/cio/chp.c
@@ -143,21 +143,14 @@ static ssize_t chp_measurement_chars_read(struct kobject *kobj,
 {
         struct channel_path *chp;
         struct device *device;
-        unsigned int size;
 
         device = container_of(kobj, struct device, kobj);
         chp = to_channelpath(device);
         if (!chp->cmg_chars)
                 return 0;
 
-        size = sizeof(struct cmg_chars);
-
-        if (off > size)
-                return 0;
-        if (off + count > size)
-                count = size - off;
-        memcpy(buf, chp->cmg_chars + off, count);
-        return count;
+        return memory_read_from_buffer(buf, count, &off,
+                                chp->cmg_chars, sizeof(struct cmg_chars));
 }
 
 static struct bin_attribute chp_measurement_chars_attr = {