fs/yaffs2/yaffs_packedtags1.c

   1 /*
   2  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
   3  *
   4  * Copyright (C) 2002-2011 Aleph One Ltd.
   5  *   for Toby Churchill Ltd and Brightstar Engineering
   6  *
   7  * Created by Charles Manning <charles@aleph1.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include "yaffs_packedtags1.h"
  15 #include "yportenv.h"
  16
  17 static const u8 all_ff[20] = {
  18         0xff, 0xff, 0xff, 0xff,
  19         0xff, 0xff, 0xff, 0xff,
  20         0xff, 0xff, 0xff, 0xff,
  21         0xff, 0xff, 0xff, 0xff,
  22         0xff, 0xff, 0xff, 0xff
  23 };
  24
  25 void yaffs_pack_tags1(struct yaffs_packed_tags1 *pt,
  26                       const struct yaffs_ext_tags *t)
  27 {
  28         pt->chunk_id = t->chunk_id;
  29         pt->serial_number = t->serial_number;
  30         pt->n_bytes = t->n_bytes;
  31         pt->obj_id = t->obj_id;
  32         pt->ecc = 0;
  33         pt->deleted = (t->is_deleted) ? 0 : 1;
  34         pt->unused_stuff = 0;
  35         pt->should_be_ff = 0xffffffff;
  36 }
  37
  38 void yaffs_unpack_tags1(struct yaffs_ext_tags *t,
  39                         const struct yaffs_packed_tags1 *pt)
  40 {
  41
  42         if (memcmp(all_ff, pt, sizeof(struct yaffs_packed_tags1))) {
  43                 t->block_bad = 0;
  44                 if (pt->should_be_ff != 0xffffffff)
  45                         t->block_bad = 1;
  46                 t->chunk_used = 1;
  47                 t->obj_id = pt->obj_id;
  48                 t->chunk_id = pt->chunk_id;
  49                 t->n_bytes = pt->n_bytes;
  50                 t->ecc_result = YAFFS_ECC_RESULT_NO_ERROR;
  51                 t->is_deleted = (pt->deleted) ? 0 : 1;
  52                 t->serial_number = pt->serial_number;
  53         } else {
  54                 memset(t, 0, sizeof(struct yaffs_ext_tags));
  55         }
  56 }