LXR linux-old/fs/jfs/jfs

   1/*
   2 *   Copyright (c) International Business Machines Corp., 2000-2002
   3 *   Portions Copyright (c) Christoph Hellwig, 2001-2002
   4 *
   5 *   This program is free software;  you can redistribute it and/or modify
   6 *   it under the terms of the GNU General Public License as published by
   7 *   the Free Software Foundation; either version 2 of the License, or 
   8 *   (at your option) any later version.
   9 * 
  10 *   This program is distributed in the hope that it will be useful,
  11 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  13 *   the GNU General Public License for more details.
  14 *
  15 *   You should have received a copy of the GNU General Public License
  16 *   along with this program;  if not, write to the Free Software 
  17 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18 */
  19#ifndef _H_JFS_METAPAGE
  20#define _H_JFS_METAPAGE
  21
  22#include <linux/pagemap.h>
  23
  24struct metapage {
  25        /* Common logsyncblk prefix (see jfs_logmgr.h) */
  26        u16 xflag;
  27        u16 unused;
  28        lid_t lid;
  29        int lsn;
  30        struct list_head synclist;
  31        /* End of logsyncblk prefix */
  32
  33        unsigned long flag;     /* See Below */
  34        unsigned long count;    /* Reference count */
  35        void *data;             /* Data pointer */
  36
  37        /* list management stuff */
  38        struct metapage *hash_prev;
  39        struct metapage *hash_next;     /* Also used for free list */
  40
  41        /*
  42         * mapping & index become redundant, but we need these here to
  43         * add the metapage to the hash before we have the real page
  44         */
  45        struct address_space *mapping;
  46        unsigned long index;
  47        wait_queue_head_t wait;
  48
  49        /* implementation */
  50        struct page *page;
  51        unsigned long logical_size;
  52
  53        /* Journal management */
  54        int clsn;
  55        atomic_t nohomeok;
  56        struct jfs_log *log;
  57};
  58
  59/* metapage flag */
  60#define META_locked     0
  61#define META_absolute   1
  62#define META_free       2
  63#define META_dirty      3
  64#define META_sync       4
  65#define META_discard    5
  66#define META_forced     6
  67#define META_stale      7
  68
  69#define mark_metapage_dirty(mp) set_bit(META_dirty, &(mp)->flag)
  70
  71/* function prototypes */
  72extern struct metapage *__get_metapage(struct inode *inode,
  73                                  unsigned long lblock, unsigned int size,
  74                                  int absolute, unsigned long new);
  75
  76#define read_metapage(inode, lblock, size, absolute)\
  77         __get_metapage(inode, lblock, size, absolute, FALSE)
  78
  79#define get_metapage(inode, lblock, size, absolute)\
  80         __get_metapage(inode, lblock, size, absolute, TRUE)
  81
  82extern void release_metapage(struct metapage *);
  83extern void hold_metapage(struct metapage *, int);
  84
  85static inline void write_metapage(struct metapage *mp)
  86{
  87        set_bit(META_dirty, &mp->flag);
  88        release_metapage(mp);
  89}
  90
  91static inline void flush_metapage(struct metapage *mp)
  92{
  93        set_bit(META_sync, &mp->flag);
  94        write_metapage(mp);
  95}
  96
  97static inline void discard_metapage(struct metapage *mp)
  98{
  99        clear_bit(META_dirty, &mp->flag);
 100        set_bit(META_discard, &mp->flag);
 101        release_metapage(mp);
 102}
 103
 104/*
 105 * This routines invalidate all pages for an extent.
 106 */
 107extern void __invalidate_metapages(struct inode *, s64, int);
 108#define invalidate_pxd_metapages(ip, pxd) \
 109        __invalidate_metapages((ip), addressPXD(&(pxd)), lengthPXD(&(pxd)))
 110#define invalidate_dxd_metapages(ip, dxd) \
 111        __invalidate_metapages((ip), addressDXD(&(dxd)), lengthDXD(&(dxd)))
 112#define invalidate_xad_metapages(ip, xad) \
 113        __invalidate_metapages((ip), addressXAD(&(xad)), lengthXAD(&(xad)))
 114
 115#endif                          /* _H_JFS_METAPAGE */
 116