bmap.h 1.8 KB

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