alloc.h 3.9 KB

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  1. /*
  2. * alloc.h - persistent object (dat entry/disk inode) allocator/deallocator
  3. *
  4. * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  5. *
  6. * This program is free software; you can redistribute it and/or modify
  7. * it under the terms of the GNU General Public License as published by
  8. * the Free Software Foundation; either version 2 of the License, or
  9. * (at your option) any later version.
  10. *
  11. * This program is distributed in the hope that it will be useful,
  12. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14. * GNU General Public License for more details.
  15. *
  16. * You should have received a copy of the GNU General Public License
  17. * along with this program; if not, write to the Free Software
  18. * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19. *
  20. * Original code was written by Koji Sato <koji@osrg.net>.
  21. * Two allocators were unified by Ryusuke Konishi <ryusuke@osrg.net>,
  22. * Amagai Yoshiji <amagai@osrg.net>.
  23. */
  24. #ifndef _NILFS_ALLOC_H
  25. #define _NILFS_ALLOC_H
  26. #include <linux/types.h>
  27. #include <linux/buffer_head.h>
  28. #include <linux/fs.h>
  29. /**
  30. * nilfs_palloc_entries_per_group - get the number of entries per group
  31. * @inode: inode of metadata file using this allocator
  32. *
  33. * The number of entries per group is defined by the number of bits
  34. * that a bitmap block can maintain.
  35. */
  36. static inline unsigned long
  37. nilfs_palloc_entries_per_group(const struct inode *inode)
  38. {
  39. return 1UL << (inode->i_blkbits + 3 /* log2(8 = CHAR_BITS) */);
  40. }
  41. int nilfs_palloc_init_blockgroup(struct inode *, unsigned);
  42. int nilfs_palloc_get_entry_block(struct inode *, __u64, int,
  43. struct buffer_head **);
  44. void *nilfs_palloc_block_get_entry(const struct inode *, __u64,
  45. const struct buffer_head *, void *);
  46. int nilfs_palloc_count_max_entries(struct inode *, u64, u64 *);
  47. /**
  48. * nilfs_palloc_req - persistent allocator request and reply
  49. * @pr_entry_nr: entry number (vblocknr or inode number)
  50. * @pr_desc_bh: buffer head of the buffer containing block group descriptors
  51. * @pr_bitmap_bh: buffer head of the buffer containing a block group bitmap
  52. * @pr_entry_bh: buffer head of the buffer containing translation entries
  53. */
  54. struct nilfs_palloc_req {
  55. __u64 pr_entry_nr;
  56. struct buffer_head *pr_desc_bh;
  57. struct buffer_head *pr_bitmap_bh;
  58. struct buffer_head *pr_entry_bh;
  59. };
  60. int nilfs_palloc_prepare_alloc_entry(struct inode *,
  61. struct nilfs_palloc_req *);
  62. void nilfs_palloc_commit_alloc_entry(struct inode *,
  63. struct nilfs_palloc_req *);
  64. void nilfs_palloc_abort_alloc_entry(struct inode *, struct nilfs_palloc_req *);
  65. void nilfs_palloc_commit_free_entry(struct inode *, struct nilfs_palloc_req *);
  66. int nilfs_palloc_prepare_free_entry(struct inode *, struct nilfs_palloc_req *);
  67. void nilfs_palloc_abort_free_entry(struct inode *, struct nilfs_palloc_req *);
  68. int nilfs_palloc_freev(struct inode *, __u64 *, size_t);
  69. #define nilfs_set_bit_atomic ext2_set_bit_atomic
  70. #define nilfs_clear_bit_atomic ext2_clear_bit_atomic
  71. #define nilfs_find_next_zero_bit find_next_zero_bit_le
  72. #define nilfs_find_next_bit find_next_bit_le
  73. /**
  74. * struct nilfs_bh_assoc - block offset and buffer head association
  75. * @blkoff: block offset
  76. * @bh: buffer head
  77. */
  78. struct nilfs_bh_assoc {
  79. unsigned long blkoff;
  80. struct buffer_head *bh;
  81. };
  82. /**
  83. * struct nilfs_palloc_cache - persistent object allocator cache
  84. * @lock: cache protecting lock
  85. * @prev_desc: blockgroup descriptors cache
  86. * @prev_bitmap: blockgroup bitmap cache
  87. * @prev_entry: translation entries cache
  88. */
  89. struct nilfs_palloc_cache {
  90. spinlock_t lock;
  91. struct nilfs_bh_assoc prev_desc;
  92. struct nilfs_bh_assoc prev_bitmap;
  93. struct nilfs_bh_assoc prev_entry;
  94. };
  95. void nilfs_palloc_setup_cache(struct inode *inode,
  96. struct nilfs_palloc_cache *cache);
  97. void nilfs_palloc_clear_cache(struct inode *inode);
  98. void nilfs_palloc_destroy_cache(struct inode *inode);
  99. #endif /* _NILFS_ALLOC_H */