include/linux/ceph/pagelist.h

   1 #ifndef __FS_CEPH_PAGELIST_H
   2 #define __FS_CEPH_PAGELIST_H
   3
   4 #include <linux/list.h>
   5
   6 struct ceph_pagelist {
   7         struct list_head head;
   8         void *mapped_tail;
   9         size_t length;
  10         size_t room;
  11         struct list_head free_list;
  12         size_t num_pages_free;
  13 };
  14
  15 struct ceph_pagelist_cursor {
  16         struct ceph_pagelist *pl;   /* pagelist, for error checking */
  17         struct list_head *page_lru; /* page in list */
  18         size_t room;                /* room remaining to reset to */
  19 };
  20
  21 static inline void ceph_pagelist_init(struct ceph_pagelist *pl)
  22 {
  23         INIT_LIST_HEAD(&pl->head);
  24         pl->mapped_tail = NULL;
  25         pl->length = 0;
  26         pl->room = 0;
  27         INIT_LIST_HEAD(&pl->free_list);
  28         pl->num_pages_free = 0;
  29 }
  30
  31 extern int ceph_pagelist_release(struct ceph_pagelist *pl);
  32
  33 extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
  34
  35 extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
  36
  37 extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
  38
  39 extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
  40                                      struct ceph_pagelist_cursor *c);
  41
  42 extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
  43                                   struct ceph_pagelist_cursor *c);
  44
  45 static inline int ceph_pagelist_encode_64(struct ceph_pagelist *pl, u64 v)
  46 {
  47         __le64 ev = cpu_to_le64(v);
  48         return ceph_pagelist_append(pl, &ev, sizeof(ev));
  49 }
  50 static inline int ceph_pagelist_encode_32(struct ceph_pagelist *pl, u32 v)
  51 {
  52         __le32 ev = cpu_to_le32(v);
  53         return ceph_pagelist_append(pl, &ev, sizeof(ev));
  54 }
  55 static inline int ceph_pagelist_encode_16(struct ceph_pagelist *pl, u16 v)
  56 {
  57         __le16 ev = cpu_to_le16(v);
  58         return ceph_pagelist_append(pl, &ev, sizeof(ev));
  59 }
  60 static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
  61 {
  62         return ceph_pagelist_append(pl, &v, 1);
  63 }
  64 static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl,
  65                                               char *s, size_t len)
  66 {
  67         int ret = ceph_pagelist_encode_32(pl, len);
  68         if (ret)
  69                 return ret;
  70         if (len)
  71                 return ceph_pagelist_append(pl, s, len);
  72         return 0;
  73 }
  74
  75 #endif