LU-1203 mdt: map old params to new ones by using an array

[fs/lustre-release.git] / lustre / obdclass / obd_config.c

diff --git a/lustre/obdclass/obd_config.c b/lustre/obdclass/obd_config.c
index 7d82c5b..1ac5b87 100644 (file)
--- a/lustre/obdclass/obd_config.c
+++ b/lustre/obdclass/obd_config.c
@@ -77,6 +77,47 @@ int class_find_param(char *buf, char *key, char **valp)
 EXPORT_SYMBOL(class_find_param);
 
 /**
+ * Check whether the proc parameter \a param is an old parameter or not from
+ * the array \a ptr which contains the mapping from old parameters to new ones.
+ * If it's an old one, then return the pointer to the cfg_interop_param struc-
+ * ture which contains both the old and new parameters.
+ *
+ * \param param                        proc parameter
+ * \param ptr                  an array which contains the mapping from
+ *                             old parameters to new ones
+ *
+ * \retval valid-pointer       pointer to the cfg_interop_param structure
+ *                             which contains the old and new parameters
+ * \retval NULL                        \a param or \a ptr is NULL,
+ *                             or \a param is not an old parameter
+ */
+struct cfg_interop_param *class_find_old_param(const char *param,
+                                              struct cfg_interop_param *ptr)
+{
+       char *value = NULL;
+       int   name_len = 0;
+
+       if (param == NULL || ptr == NULL)
+               RETURN(NULL);
+
+       value = strchr(param, '=');
+       if (value == NULL)
+               name_len = strlen(param);
+       else
+               name_len = value - param;
+
+       while (ptr->old_param != NULL) {
+               if (strncmp(param, ptr->old_param, name_len) == 0 &&
+                   name_len == strlen(ptr->old_param))
+                       RETURN(ptr);
+               ptr++;
+       }
+
+       RETURN(NULL);
+}
+EXPORT_SYMBOL(class_find_old_param);
+
+/**
  * Finds a parameter in \a params and copies it to \a copy.
  *
  * Leading spaces are skipped. Next space or end of string is the