include/ust/kcompat/simple.h

   1 /*
   2  * simple.h
   3  *
   4  * Copyright (C) 2009 - Pierre-Marc Fournier (pierre-marc dot fournier at polymtl dot ca)
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifndef KCOMPAT_SIMPLE_H
  22 #define KCOMPAT_SIMPLE_H
  23
  24 /**
  25  * container_of - cast a member of a structure out to the containing structure
  26  * @ptr:        the pointer to the member.
  27  * @type:       the type of the container struct this is embedded in.
  28  * @member:     the name of the member within the struct.
  29  *
  30  */
  31 #define container_of(ptr, type, member) ({                      \
  32         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
  33         (type *)( (char *)__mptr - offsetof(type,member) );})
  34
  35
  36 /* libkcompat: from rcupdate.h */
  37
  38 struct rcu_head {
  39         struct rcu_head *next;
  40         void (*func)(struct rcu_head *head);
  41 };
  42
  43 #endif /* KCOMPAT_SIMPLE_H */