mei: connection to fixed address clients from user-space

This should be used for debug only.
The feaure is gated by "allow_fixed_address" control exposed in debugfs.

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>

diff --git a/drivers/misc/mei/debugfs.c b/drivers/misc/mei/debugfs.c
index 3f6d855..88f5fd0 100644 (file)
--- a/drivers/misc/mei/debugfs.c
+++ b/drivers/misc/mei/debugfs.c
@@ -209,6 +209,12 @@ int mei_dbgfs_register(struct mei_device *dev, const char *name)
                dev_err(dev->dev, "devstate: registration failed\n");
                goto err;
        }
+       f = debugfs_create_bool("allow_fixed_address", S_IRUSR | S_IWUSR, dir,
+                               &dev->allow_fixed_address);
+       if (!f) {
+               dev_err(dev->dev, "allow_fixed_address: registration failed\n");
+               goto err;
+       }
        dev->dbgfs_dir = dir;
        return 0;
 err:

diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index a696365..2887e56 100644 (file)
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -215,6 +215,11 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 
        cb = mei_cl_read_cb(cl, file);
        if (!cb) {
+               if (mei_cl_is_fixed_address(cl) && dev->allow_fixed_address) {
+                       cb = mei_cl_read_cb(cl, NULL);
+                       if (cb)
+                               goto copy_buffer;
+               }
                rets = 0;
                goto out;
        }
@@ -389,7 +394,8 @@ static int mei_ioctl_connect_client(struct file *file,
 
        /* find ME client we're trying to connect to */
        me_cl = mei_me_cl_by_uuid(dev, &data->in_client_uuid);
-       if (!me_cl || me_cl->props.fixed_address) {
+       if (!me_cl ||
+           (me_cl->props.fixed_address && !dev->allow_fixed_address)) {
                dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n",
                        &data->in_client_uuid);
                mei_me_cl_put(me_cl);

diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index 96c0290..fa5ce1d 100644 (file)
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -476,6 +476,8 @@ const char *mei_pg_state_str(enum mei_pg_state state);
  * @host_clients_map : host clients id pool
  * @me_client_index : last FW client index in enumeration
  *
+ * @allow_fixed_address: allow user space to connect a fixed client
+ *
  * @wd_cl       : watchdog client
  * @wd_state    : watchdog client state
  * @wd_pending  : watchdog command is pending
@@ -567,6 +569,8 @@ struct mei_device {
        DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
        unsigned long me_client_index;
 
+       u32 allow_fixed_address;
+
        struct mei_cl wd_cl;
        enum mei_wd_states wd_state;
        bool wd_pending;