xfs_iomap.h 3.5 KB

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  1. /*
  2. * Copyright (c) 2003-2005 Silicon Graphics, Inc.
  3. * All Rights Reserved.
  4. *
  5. * This program is free software; you can redistribute it and/or
  6. * modify it under the terms of the GNU General Public License as
  7. * published by the Free Software Foundation.
  8. *
  9. * This program is distributed in the hope that it would be useful,
  10. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12. * GNU General Public License for more details.
  13. *
  14. * You should have received a copy of the GNU General Public License
  15. * along with this program; if not, write the Free Software Foundation,
  16. * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  17. */
  18. #ifndef __XFS_IOMAP_H__
  19. #define __XFS_IOMAP_H__
  20. #define IOMAP_DADDR_NULL ((xfs_daddr_t) (-1LL))
  21. typedef enum { /* iomap_flags values */
  22. IOMAP_EOF = 0x01, /* mapping contains EOF */
  23. IOMAP_HOLE = 0x02, /* mapping covers a hole */
  24. IOMAP_DELAY = 0x04, /* mapping covers delalloc region */
  25. IOMAP_REALTIME = 0x10, /* mapping on the realtime device */
  26. IOMAP_UNWRITTEN = 0x20, /* mapping covers allocated */
  27. /* but uninitialized file data */
  28. IOMAP_NEW = 0x40 /* just allocate */
  29. } iomap_flags_t;
  30. typedef enum {
  31. /* base extent manipulation calls */
  32. BMAPI_READ = (1 << 0), /* read extents */
  33. BMAPI_WRITE = (1 << 1), /* create extents */
  34. BMAPI_ALLOCATE = (1 << 2), /* delayed allocate to real extents */
  35. BMAPI_UNWRITTEN = (1 << 3), /* unwritten extents to real extents */
  36. /* modifiers */
  37. BMAPI_IGNSTATE = (1 << 4), /* ignore unwritten state on read */
  38. BMAPI_DIRECT = (1 << 5), /* direct instead of buffered write */
  39. BMAPI_MMAP = (1 << 6), /* allocate for mmap write */
  40. BMAPI_SYNC = (1 << 7), /* sync write to flush delalloc space */
  41. BMAPI_TRYLOCK = (1 << 8), /* non-blocking request */
  42. BMAPI_DEVICE = (1 << 9), /* we only want to know the device */
  43. } bmapi_flags_t;
  44. /*
  45. * xfs_iomap_t: File system I/O map
  46. *
  47. * The iomap_bn field is expressed in 512-byte blocks, and is where the
  48. * mapping starts on disk.
  49. *
  50. * The iomap_offset, iomap_bsize and iomap_delta fields are in bytes.
  51. * iomap_offset is the offset of the mapping in the file itself.
  52. * iomap_bsize is the size of the mapping, iomap_delta is the
  53. * desired data's offset into the mapping, given the offset supplied
  54. * to the file I/O map routine.
  55. *
  56. * When a request is made to read beyond the logical end of the object,
  57. * iomap_size may be set to 0, but iomap_offset and iomap_length should be set
  58. * to the actual amount of underlying storage that has been allocated, if any.
  59. */
  60. typedef struct xfs_iomap {
  61. xfs_daddr_t iomap_bn; /* first 512b blk of mapping */
  62. xfs_buftarg_t *iomap_target;
  63. xfs_off_t iomap_offset; /* offset of mapping, bytes */
  64. xfs_off_t iomap_bsize; /* size of mapping, bytes */
  65. xfs_off_t iomap_delta; /* offset into mapping, bytes */
  66. iomap_flags_t iomap_flags;
  67. } xfs_iomap_t;
  68. struct xfs_iocore;
  69. struct xfs_inode;
  70. struct xfs_bmbt_irec;
  71. extern int xfs_iomap(struct xfs_iocore *, xfs_off_t, ssize_t, int,
  72. struct xfs_iomap *, int *);
  73. extern int xfs_iomap_write_direct(struct xfs_inode *, xfs_off_t, size_t,
  74. int, struct xfs_bmbt_irec *, int *, int);
  75. extern int xfs_iomap_write_delay(struct xfs_inode *, xfs_off_t, size_t, int,
  76. struct xfs_bmbt_irec *, int *);
  77. extern int xfs_iomap_write_allocate(struct xfs_inode *, xfs_off_t, size_t,
  78. struct xfs_bmbt_irec *, int *);
  79. extern int xfs_iomap_write_unwritten(struct xfs_inode *, xfs_off_t, size_t);
  80. #endif /* __XFS_IOMAP_H__*/