LXR linux/include/linux/ceph/pagelist.h

   1#ifndef __FS_CEPH_PAGELIST_H
   2#define __FS_CEPH_PAGELIST_H
   3
   4#include <asm/byteorder.h>
   5#include <linux/atomic.h>
   6#include <linux/list.h>
   7#include <linux/types.h>
   8
   9struct ceph_pagelist {
  10        struct list_head head;
  11        void *mapped_tail;
  12        size_t length;
  13        size_t room;
  14        struct list_head free_list;
  15        size_t num_pages_free;
  16        atomic_t refcnt;
  17};
  18
  19struct ceph_pagelist_cursor {
  20        struct ceph_pagelist *pl;   /* pagelist, for error checking */
  21        struct list_head *page_lru; /* page in list */
  22        size_t room;                /* room remaining to reset to */
  23};
  24
  25static inline void ceph_pagelist_init(struct ceph_pagelist *pl)
  26{
  27        INIT_LIST_HEAD(&pl->head);
  28        pl->mapped_tail = NULL;
  29        pl->length = 0;
  30        pl->room = 0;
  31        INIT_LIST_HEAD(&pl->free_list);
  32        pl->num_pages_free = 0;
  33        atomic_set(&pl->refcnt, 1);
  34}
  35
  36extern void ceph_pagelist_release(struct ceph_pagelist *pl);
  37
  38extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
  39
  40extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
  41
  42extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
  43
  44extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
  45                                     struct ceph_pagelist_cursor *c);
  46
  47extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
  48                                  struct ceph_pagelist_cursor *c);
  49
  50static inline int ceph_pagelist_encode_64(struct ceph_pagelist *pl, u64 v)
  51{
  52        __le64 ev = cpu_to_le64(v);
  53        return ceph_pagelist_append(pl, &ev, sizeof(ev));
  54}
  55static inline int ceph_pagelist_encode_32(struct ceph_pagelist *pl, u32 v)
  56{
  57        __le32 ev = cpu_to_le32(v);
  58        return ceph_pagelist_append(pl, &ev, sizeof(ev));
  59}
  60static inline int ceph_pagelist_encode_16(struct ceph_pagelist *pl, u16 v)
  61{
  62        __le16 ev = cpu_to_le16(v);
  63        return ceph_pagelist_append(pl, &ev, sizeof(ev));
  64}
  65static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
  66{
  67        return ceph_pagelist_append(pl, &v, 1);
  68}
  69static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl,
  70                                              char *s, size_t len)
  71{
  72        int ret = ceph_pagelist_encode_32(pl, len);
  73        if (ret)
  74                return ret;
  75        if (len)
  76                return ceph_pagelist_append(pl, s, len);
  77        return 0;
  78}
  79
  80#endif
  81