runlist.h 3.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102
  1. /*
  2. * runlist.h - Defines for runlist handling in NTFS Linux kernel driver.
  3. * Part of the Linux-NTFS project.
  4. *
  5. * Copyright (c) 2001-2005 Anton Altaparmakov
  6. * Copyright (c) 2002 Richard Russon
  7. *
  8. * This program/include file is free software; you can redistribute it and/or
  9. * modify it under the terms of the GNU General Public License as published
  10. * by the Free Software Foundation; either version 2 of the License, or
  11. * (at your option) any later version.
  12. *
  13. * This program/include file is distributed in the hope that it will be
  14. * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  15. * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16. * GNU General Public License for more details.
  17. *
  18. * You should have received a copy of the GNU General Public License
  19. * along with this program (in the main directory of the Linux-NTFS
  20. * distribution in the file COPYING); if not, write to the Free Software
  21. * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22. */
  23. #ifndef _LINUX_NTFS_RUNLIST_H
  24. #define _LINUX_NTFS_RUNLIST_H
  25. #include "types.h"
  26. #include "layout.h"
  27. #include "volume.h"
  28. /**
  29. * runlist_element - in memory vcn to lcn mapping array element
  30. * @vcn: starting vcn of the current array element
  31. * @lcn: starting lcn of the current array element
  32. * @length: length in clusters of the current array element
  33. *
  34. * The last vcn (in fact the last vcn + 1) is reached when length == 0.
  35. *
  36. * When lcn == -1 this means that the count vcns starting at vcn are not
  37. * physically allocated (i.e. this is a hole / data is sparse).
  38. */
  39. typedef struct { /* In memory vcn to lcn mapping structure element. */
  40. VCN vcn; /* vcn = Starting virtual cluster number. */
  41. LCN lcn; /* lcn = Starting logical cluster number. */
  42. s64 length; /* Run length in clusters. */
  43. } runlist_element;
  44. /**
  45. * runlist - in memory vcn to lcn mapping array including a read/write lock
  46. * @rl: pointer to an array of runlist elements
  47. * @lock: read/write spinlock for serializing access to @rl
  48. *
  49. */
  50. typedef struct {
  51. runlist_element *rl;
  52. struct rw_semaphore lock;
  53. } runlist;
  54. static inline void ntfs_init_runlist(runlist *rl)
  55. {
  56. rl->rl = NULL;
  57. init_rwsem(&rl->lock);
  58. }
  59. typedef enum {
  60. LCN_HOLE = -1, /* Keep this as highest value or die! */
  61. LCN_RL_NOT_MAPPED = -2,
  62. LCN_ENOENT = -3,
  63. LCN_ENOMEM = -4,
  64. LCN_EIO = -5,
  65. } LCN_SPECIAL_VALUES;
  66. extern runlist_element *ntfs_runlists_merge(runlist_element *drl,
  67. runlist_element *srl);
  68. extern runlist_element *ntfs_mapping_pairs_decompress(const ntfs_volume *vol,
  69. const ATTR_RECORD *attr, runlist_element *old_rl);
  70. extern LCN ntfs_rl_vcn_to_lcn(const runlist_element *rl, const VCN vcn);
  71. #ifdef NTFS_RW
  72. extern runlist_element *ntfs_rl_find_vcn_nolock(runlist_element *rl,
  73. const VCN vcn);
  74. extern int ntfs_get_size_for_mapping_pairs(const ntfs_volume *vol,
  75. const runlist_element *rl, const VCN first_vcn,
  76. const VCN last_vcn);
  77. extern int ntfs_mapping_pairs_build(const ntfs_volume *vol, s8 *dst,
  78. const int dst_len, const runlist_element *rl,
  79. const VCN first_vcn, const VCN last_vcn, VCN *const stop_vcn);
  80. extern int ntfs_rl_truncate_nolock(const ntfs_volume *vol,
  81. runlist *const runlist, const s64 new_length);
  82. int ntfs_rl_punch_nolock(const ntfs_volume *vol, runlist *const runlist,
  83. const VCN start, const s64 length);
  84. #endif /* NTFS_RW */
  85. #endif /* _LINUX_NTFS_RUNLIST_H */