mei: debugfs: adjust print buffer

In case of many me clients (15 and more) 1K buffer
is not enough for full information print.
Calculate buffer size according to real clients number.

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

1 files changed, 15 insertions, 7 deletions

diff --git a/drivers/misc/mei/debugfs.c b/drivers/misc/mei/debugfs.c
index 2399b3181e6c..ca2a12d702a9 100644
--- a/drivers/misc/mei/debugfs.c
+++ b/drivers/misc/mei/debugfs.c
@@ -29,20 +29,28 @@ static ssize_t mei_dbgfs_read_meclients(struct file *fp, char __user *ubuf,
 {
         struct mei_device *dev = fp->private_data;
         struct mei_me_client *me_cl;
-        const size_t bufsz = 1024;
-        char *buf = kzalloc(bufsz, GFP_KERNEL);
+        size_t bufsz = 1;
+        char *buf;
         int i = 0;
         int pos = 0;
         int ret;
 
-        if  (!buf)
-                return -ENOMEM;
-
-        pos += scnprintf(buf + pos, bufsz - pos,
-                        "  |id|addr|         UUID                       |con|msg len|\n");
+#define HDR "  |id|addr|         UUID                       |con|msg len|\n"
 
         mutex_lock(&dev->device_lock);
 
+        list_for_each_entry(me_cl, &dev->me_clients, list)
+                bufsz++;
+
+        bufsz *= sizeof(HDR) + 1;
+        buf = kzalloc(bufsz, GFP_KERNEL);
+        if (!buf) {
+                mutex_unlock(&dev->device_lock);
+                return -ENOMEM;
+        }
+
+        pos += scnprintf(buf + pos, bufsz - pos, HDR);
+
         /*  if the driver is not enabled the list won't be consistent */
         if (dev->dev_state != MEI_DEV_ENABLED)
                 goto out;