[patch] drm/msm: return -EFAULT instead of bytes remaining

[Dan Carpenter]

copy_to/from_user returns the number of bytes remaining to be copied but
we want to return -EFAULT.

Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>

diff --git a/drivers/gpu/drm/msm/msm_perf.c b/drivers/gpu/drm/msm/msm_perf.c
index 830857c..17fe4e5 100644
--- a/drivers/gpu/drm/msm/msm_perf.c
+++ b/drivers/gpu/drm/msm/msm_perf.c
@@ -132,7 +132,7 @@ static ssize_t perf_read(struct file *file, char __user 
*buf,
                size_t sz, loff_t *ppos)
 {
        struct msm_perf_state *perf = file->private_data;
-       int n = 0, ret;
+       int n = 0, ret = 0;

        mutex_lock(&perf->read_lock);

@@ -143,9 +143,10 @@ static ssize_t perf_read(struct file *file, char __user 
*buf,
        }

        n = min((int)sz, perf->buftot - perf->bufpos);
-       ret = copy_to_user(buf, &perf->buf[perf->bufpos], n);
-       if (ret)
+       if (copy_to_user(buf, &perf->buf[perf->bufpos], n)) {
+               ret = -EFAULT;
                goto out;
+       }

        perf->bufpos += n;
        *ppos += n;
diff --git a/drivers/gpu/drm/msm/msm_rd.c b/drivers/gpu/drm/msm/msm_rd.c
index 24254e0..3a5fdfc 100644
--- a/drivers/gpu/drm/msm/msm_rd.c
+++ b/drivers/gpu/drm/msm/msm_rd.c
@@ -149,9 +149,10 @@ static ssize_t rd_read(struct file *file, char __user *buf,
                goto out;

        n = min_t(int, sz, circ_count_to_end(&rd->fifo));
-       ret = copy_to_user(buf, fptr, n);
-       if (ret)
+       if (copy_to_user(buf, fptr, n)) {
+               ret = -EFAULT;
                goto out;
+       }

        fifo->tail = (fifo->tail + n) & (BUF_SZ - 1);
        *ppos += n;