3525 Persistent L2ARC

*** 20,41 ****
   */
  /*
   * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
  #ifndef _SYS_LIST_H
  #define _SYS_LIST_H
  
- #pragma ident   "%Z%%M% %I%     %E% SMI"
- 
  #include <sys/list_impl.h>
  
  #ifdef  __cplusplus
  extern "C" {
  #endif
  
  typedef struct list_node list_node_t;
  typedef struct list list_t;
  
  void list_create(list_t *, size_t, size_t);
  void list_destroy(list_t *);
--- 20,55 ----
   */
  /*
   * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
+ /*
+  * Copyright 2013 Saso Kiselkov, All rights reserved.
+  */
  
  #ifndef _SYS_LIST_H
  #define _SYS_LIST_H
  
  #include <sys/list_impl.h>
  
  #ifdef  __cplusplus
  extern "C" {
  #endif
  
+ /*
+  * Please note that a list_node_t contains pointers back to its parent list_t
+  * so you cannot copy the list_t around once it has been initialized. In
+  * particular, this kind of construct won't work:
+  *
+  * struct { list_t l; } a, b;
+  * list_create(&a.l, ...);
+  * b = a;    <= This will break the list in `b', as the `l' element in `a'
+  *              got copied to a different memory address.
+  *
+  * When copying structures with lists use list_move_tail() to move the list
+  * from the src to dst (the source reference will then become invalid).
+  */
  typedef struct list_node list_node_t;
  typedef struct list list_t;
  
  void list_create(list_t *, size_t, size_t);
  void list_destroy(list_t *);