pagelist.h 2.0 KB

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  1. #ifndef __FS_CEPH_PAGELIST_H
  2. #define __FS_CEPH_PAGELIST_H
  3. #include <linux/list.h>
  4. #include <linux/atomic.h>
  5. struct ceph_pagelist {
  6. struct list_head head;
  7. void *mapped_tail;
  8. size_t length;
  9. size_t room;
  10. struct list_head free_list;
  11. size_t num_pages_free;
  12. atomic_t refcnt;
  13. };
  14. struct ceph_pagelist_cursor {
  15. struct ceph_pagelist *pl; /* pagelist, for error checking */
  16. struct list_head *page_lru; /* page in list */
  17. size_t room; /* room remaining to reset to */
  18. };
  19. static inline void ceph_pagelist_init(struct ceph_pagelist *pl)
  20. {
  21. INIT_LIST_HEAD(&pl->head);
  22. pl->mapped_tail = NULL;
  23. pl->length = 0;
  24. pl->room = 0;
  25. INIT_LIST_HEAD(&pl->free_list);
  26. pl->num_pages_free = 0;
  27. atomic_set(&pl->refcnt, 1);
  28. }
  29. extern void ceph_pagelist_release(struct ceph_pagelist *pl);
  30. extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
  31. extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
  32. extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
  33. extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
  34. struct ceph_pagelist_cursor *c);
  35. extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
  36. struct ceph_pagelist_cursor *c);
  37. static inline int ceph_pagelist_encode_64(struct ceph_pagelist *pl, u64 v)
  38. {
  39. __le64 ev = cpu_to_le64(v);
  40. return ceph_pagelist_append(pl, &ev, sizeof(ev));
  41. }
  42. static inline int ceph_pagelist_encode_32(struct ceph_pagelist *pl, u32 v)
  43. {
  44. __le32 ev = cpu_to_le32(v);
  45. return ceph_pagelist_append(pl, &ev, sizeof(ev));
  46. }
  47. static inline int ceph_pagelist_encode_16(struct ceph_pagelist *pl, u16 v)
  48. {
  49. __le16 ev = cpu_to_le16(v);
  50. return ceph_pagelist_append(pl, &ev, sizeof(ev));
  51. }
  52. static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
  53. {
  54. return ceph_pagelist_append(pl, &v, 1);
  55. }
  56. static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl,
  57. char *s, size_t len)
  58. {
  59. int ret = ceph_pagelist_encode_32(pl, len);
  60. if (ret)
  61. return ret;
  62. if (len)
  63. return ceph_pagelist_append(pl, s, len);
  64. return 0;
  65. }
  66. #endif