fs/gfs2/bmap.h

   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 __BMAP_DOT_H__
  11 #define __BMAP_DOT_H__
  12
  13 #include <linux/iomap.h>
  14
  15 #include "inode.h"
  16
  17 struct inode;
  18 struct gfs2_inode;
  19 struct page;
  20
  21
  22 /**
  23  * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file
  24  * @ip: the file
  25  * @len: the number of bytes to be written to the file
  26  * @data_blocks: returns the number of data blocks required
  27  * @ind_blocks: returns the number of indirect blocks required
  28  *
  29  */
  30
  31 static inline void gfs2_write_calc_reserv(const struct gfs2_inode *ip,
  32                                           unsigned int len,
  33                                           unsigned int *data_blocks,
  34                                           unsigned int *ind_blocks)
  35 {
  36         const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
  37         unsigned int tmp;
  38
  39         BUG_ON(gfs2_is_dir(ip));
  40         *data_blocks = (len >> sdp->sd_sb.sb_bsize_shift) + 3;
  41         *ind_blocks = 3 * (sdp->sd_max_height - 1);
  42
  43         for (tmp = *data_blocks; tmp > sdp->sd_diptrs;) {
  44                 tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs);
  45                 *ind_blocks += tmp;
  46         }
  47 }
  48
  49 extern int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page);
  50 extern int gfs2_block_map(struct inode *inode, sector_t lblock,
  51                           struct buffer_head *bh, int create);
  52 extern int gfs2_iomap_begin(struct inode *inode, loff_t pos, loff_t length,
  53                             unsigned flags, struct iomap *iomap);
  54 extern int gfs2_extent_map(struct inode *inode, u64 lblock, int *new,
  55                            u64 *dblock, unsigned *extlen);
  56 extern int gfs2_setattr_size(struct inode *inode, u64 size);
  57 extern void gfs2_trim_blocks(struct inode *inode);
  58 extern int gfs2_truncatei_resume(struct gfs2_inode *ip);
  59 extern int gfs2_file_dealloc(struct gfs2_inode *ip);
  60 extern int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset,
  61                                      unsigned int len);
  62 extern int gfs2_map_journal_extents(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd);
  63 extern void gfs2_free_journal_extents(struct gfs2_jdesc *jd);
  64 extern int __gfs2_punch_hole(struct file *file, loff_t offset, loff_t length);
  65
  66 #endif /* __BMAP_DOT_H__ */