fs/jfs/jfs_metapage.h

   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
  24 struct 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 */
  72 extern 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
  82 extern void release_metapage(struct metapage *);
  83 extern void hold_metapage(struct metapage *, int);
  84
  85 static inline void write_metapage(struct metapage *mp)
  86 {
  87         set_bit(META_dirty, &mp->flag);
  88         release_metapage(mp);
  89 }
  90
  91 static inline void flush_metapage(struct metapage *mp)
  92 {
  93         set_bit(META_sync, &mp->flag);
  94         write_metapage(mp);
  95 }
  96
  97 static 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  */
 107 extern 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 */