LXR linux/fs/gfs2/meta

   1/*
   2 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4 *
   5 * This copyrighted material is made available to anyone wishing to use,
   6 * modify, copy, or redistribute it subject to the terms and conditions
   7 * of the GNU General Public License version 2.
   8 */
   9
  10#ifndef __DIO_DOT_H__
  11#define __DIO_DOT_H__
  12
  13#include <linux/buffer_head.h>
  14#include <linux/string.h>
  15#include "incore.h"
  16
  17static inline void gfs2_buffer_clear(struct buffer_head *bh)
  18{
  19        memset(bh->b_data, 0, bh->b_size);
  20}
  21
  22static inline void gfs2_buffer_clear_tail(struct buffer_head *bh, int head)
  23{
  24        BUG_ON(head > bh->b_size);
  25        memset(bh->b_data + head, 0, bh->b_size - head);
  26}
  27
  28static inline void gfs2_buffer_copy_tail(struct buffer_head *to_bh,
  29                                         int to_head,
  30                                         struct buffer_head *from_bh,
  31                                         int from_head)
  32{
  33        BUG_ON(from_head < to_head);
  34        memcpy(to_bh->b_data + to_head, from_bh->b_data + from_head,
  35               from_bh->b_size - from_head);
  36        memset(to_bh->b_data + to_bh->b_size + to_head - from_head,
  37               0, from_head - to_head);
  38}
  39
  40extern const struct address_space_operations gfs2_meta_aops;
  41
  42static inline struct gfs2_sbd *gfs2_mapping2sbd(struct address_space *mapping)
  43{
  44        struct inode *inode = mapping->host;
  45        if (mapping->a_ops == &gfs2_meta_aops)
  46                return (((struct gfs2_glock *)mapping) - 1)->gl_sbd;
  47        else
  48                return inode->i_sb->s_fs_info;
  49}
  50
  51void gfs2_meta_sync(struct gfs2_glock *gl);
  52
  53struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno);
  54int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno,
  55                   int flags, struct buffer_head **bhp);
  56int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh);
  57struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create);
  58
  59void gfs2_attach_bufdata(struct gfs2_glock *gl, struct buffer_head *bh,
  60                         int meta);
  61
  62void gfs2_remove_from_journal(struct buffer_head *bh, struct gfs2_trans *tr,
  63                              int meta);
  64
  65void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen);
  66
  67int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
  68                              int new, struct buffer_head **bhp);
  69
  70static inline int gfs2_meta_inode_buffer(struct gfs2_inode *ip,
  71                                         struct buffer_head **bhp)
  72{
  73        return gfs2_meta_indirect_buffer(ip, 0, ip->i_no_addr, 0, bhp);
  74}
  75
  76struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen);
  77
  78#define buffer_busy(bh) \
  79((bh)->b_state & ((1ul << BH_Dirty) | (1ul << BH_Lock) | (1ul << BH_Pinned)))
  80#define buffer_in_io(bh) \
  81((bh)->b_state & ((1ul << BH_Dirty) | (1ul << BH_Lock)))
  82
  83#endif /* __DIO_DOT_H__ */
  84
  85