mei: fix ssize_t to int assignment in read and write ops.

Use ssize_t for rets variables in mei_write(), mei_read(), and
mei_cl_write() as well as change the return type of mei_cl_write()
to ssize_t, to prevent assignment of possible 64bit size_t
to int 32 bit variable.

As by product also eliminate warning
drivers/misc/mei/client.c:1702:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 17 insertions, 17 deletions

diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index f8fb7589192e..5a673d09585f 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -1644,13 +1644,13 @@ err:
  *
  * Return: number of bytes sent on success, <0 on failure.
  */
-int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
+ssize_t mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
 {
         struct mei_device *dev;
         struct mei_msg_data *buf;
         struct mei_msg_hdr mei_hdr;
-        int size;
-        int rets;
+        size_t len;
+        ssize_t rets;
         bool blocking;
 
         if (WARN_ON(!cl || !cl->dev))
@@ -1662,15 +1662,15 @@ int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
         dev = cl->dev;
 
         buf = &cb->buf;
-        size = buf->size;
+        len = buf->size;
         blocking = cb->blocking;
 
-        cl_dbg(dev, cl, "size=%d\n", size);
+        cl_dbg(dev, cl, "len=%zd\n", len);
 
         rets = pm_runtime_get(dev->dev);
         if (rets < 0 && rets != -EINPROGRESS) {
                 pm_runtime_put_noidle(dev->dev);
-                cl_err(dev, cl, "rpm: get failed %d\n", rets);
+                cl_err(dev, cl, "rpm: get failed %zd\n", rets);
                 goto free;
         }
 
@@ -1689,21 +1689,21 @@ int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb)
 
         if (rets == 0) {
                 cl_dbg(dev, cl, "No flow control credentials: not sending.\n");
-                rets = size;
+                rets = len;
                 goto out;
         }
         if (!mei_hbuf_acquire(dev)) {
                 cl_dbg(dev, cl, "Cannot acquire the host buffer: not sending.\n");
-                rets = size;
+                rets = len;
                 goto out;
         }
 
         /* Check for a maximum length */
-        if (size > mei_hbuf_max_len(dev)) {
+        if (len > mei_hbuf_max_len(dev)) {
                 mei_hdr.length = mei_hbuf_max_len(dev);
                 mei_hdr.msg_complete = 0;
         } else {
-                mei_hdr.length = size;
+                mei_hdr.length = len;
                 mei_hdr.msg_complete = 1;
         }
 
@@ -1745,7 +1745,7 @@ out:
                 }
         }
 
-        rets = size;
+        rets = len;
 err:
         cl_dbg(dev, cl, "rpm: autosuspend\n");
         pm_runtime_mark_last_busy(dev->dev);
diff --git a/drivers/misc/mei/client.h b/drivers/misc/mei/client.h
index 5371df4d8af3..64e318f589b4 100644
--- a/drivers/misc/mei/client.h
+++ b/drivers/misc/mei/client.h
@@ -202,7 +202,7 @@ int mei_cl_connect(struct mei_cl *cl, struct mei_me_client *me_cl,
 int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
                        struct list_head *cmpl_list);
 int mei_cl_read_start(struct mei_cl *cl, size_t length, const struct file *fp);
-int mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb);
+ssize_t mei_cl_write(struct mei_cl *cl, struct mei_cl_cb *cb);
 int mei_cl_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
                      struct list_head *cmpl_list);
 
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index 302ba7a63bd2..4d77a6ae183a 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -137,7 +137,7 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
         struct mei_device *dev;
         struct mei_cl_cb *cb = NULL;
         bool nonblock = !!(file->f_flags & O_NONBLOCK);
-        int rets;
+        ssize_t rets;
 
         if (WARN_ON(!cl || !cl->dev))
                 return -ENODEV;
@@ -170,7 +170,7 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 
         rets = mei_cl_read_start(cl, length, file);
         if (rets && rets != -EBUSY) {
-                cl_dbg(dev, cl, "mei start read failure status = %d\n", rets);
+                cl_dbg(dev, cl, "mei start read failure status = %zd\n", rets);
                 goto out;
         }
 
@@ -204,7 +204,7 @@ copy_buffer:
         /* now copy the data to user space */
         if (cb->status) {
                 rets = cb->status;
-                cl_dbg(dev, cl, "read operation failed %d\n", rets);
+                cl_dbg(dev, cl, "read operation failed %zd\n", rets);
                 goto free;
         }
 
@@ -236,7 +236,7 @@ free:
         *offset = 0;
 
 out:
-        cl_dbg(dev, cl, "end mei read rets = %d\n", rets);
+        cl_dbg(dev, cl, "end mei read rets = %zd\n", rets);
         mutex_unlock(&dev->device_lock);
         return rets;
 }
@@ -256,7 +256,7 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
         struct mei_cl *cl = file->private_data;
         struct mei_cl_cb *cb;
         struct mei_device *dev;
-        int rets;
+        ssize_t rets;
 
         if (WARN_ON(!cl || !cl->dev))
                 return -ENODEV;