release/src-rt-6.x.4708/linux/linux-2.6.36/fs/ntfs/aops.h

   1 /**
   2  * aops.h - Defines for NTFS kernel address space operations and page cache
   3  *          handling.  Part of the Linux-NTFS project.
   4  *
   5  * Copyright (c) 2001-2004 Anton Altaparmakov
   6  * Copyright (c) 2002 Richard Russon
   7  *
   8  * This program/include file is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as published
  10  * by the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program/include file is distributed in the hope that it will be
  14  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program (in the main directory of the Linux-NTFS
  20  * distribution in the file COPYING); if not, write to the Free Software
  21  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  */
  23
  24 #ifndef _LINUX_NTFS_AOPS_H
  25 #define _LINUX_NTFS_AOPS_H
  26
  27 #include <linux/mm.h>
  28 #include <linux/highmem.h>
  29 #include <linux/pagemap.h>
  30 #include <linux/fs.h>
  31
  32 #include "inode.h"
  33
  34 /**
  35  * ntfs_unmap_page - release a page that was mapped using ntfs_map_page()
  36  * @page:       the page to release
  37  *
  38  * Unpin, unmap and release a page that was obtained from ntfs_map_page().
  39  */
  40 static inline void ntfs_unmap_page(struct page *page)
  41 {
  42         kunmap(page);
  43         page_cache_release(page);
  44 }
  45
  46 static inline struct page *ntfs_map_page(struct address_space *mapping,
  47                 unsigned long index)
  48 {
  49         struct page *page = read_mapping_page(mapping, index, NULL);
  50
  51         if (!IS_ERR(page)) {
  52                 kmap(page);
  53                 if (!PageError(page))
  54                         return page;
  55                 ntfs_unmap_page(page);
  56                 return ERR_PTR(-EIO);
  57         }
  58         return page;
  59 }
  60
  61 #ifdef NTFS_RW
  62
  63 extern void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs);
  64
  65 #endif /* NTFS_RW */
  66
  67 #endif /* _LINUX_NTFS_AOPS_H */