[SCSI] ipr: use memory_read_from_buffer()

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Brian King <brking@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 5 insertions, 11 deletions

diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index d30eb7ba018..de62f4dfeb0 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -2456,20 +2456,14 @@ static ssize_t ipr_read_trace(struct kobject *kobj,
         struct Scsi_Host *shost = class_to_shost(dev);
         struct ipr_ioa_cfg *ioa_cfg = (struct ipr_ioa_cfg *)shost->hostdata;
         unsigned long lock_flags = 0;
-        int size = IPR_TRACE_SIZE;
-        char *src = (char *)ioa_cfg->trace;
-
-        if (off > size)
-                return 0;
-        if (off + count > size) {
-                size -= off;
-                count = size;
-        }
+        ssize_t ret;
 
         spin_lock_irqsave(ioa_cfg->host->host_lock, lock_flags);
-        memcpy(buf, &src[off], count);
+        ret = memory_read_from_buffer(buf, count, &off, ioa_cfg->trace,
+                                IPR_TRACE_SIZE);
         spin_unlock_irqrestore(ioa_cfg->host->host_lock, lock_flags);
-        return count;
+
+        return ret;
 }
 
 static struct bin_attribute ipr_trace_attr = {