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

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __FS_CEPH_PAGELIST_H
   3#define __FS_CEPH_PAGELIST_H
   4
   5#include <asm/byteorder.h>
   6#include <linux/refcount.h>
   7#include <linux/list.h>
   8#include <linux/types.h>
   9
  10struct ceph_pagelist {
  11        struct list_head head;
  12        void *mapped_tail;
  13        size_t length;
  14        size_t room;
  15        struct list_head free_list;
  16        size_t num_pages_free;
  17        refcount_t refcnt;
  18};
  19
  20struct ceph_pagelist_cursor {
  21        struct ceph_pagelist *pl;   /* pagelist, for error checking */
  22        struct list_head *page_lru; /* page in list */
  23        size_t room;                /* room remaining to reset to */
  24};
  25
  26struct ceph_pagelist *ceph_pagelist_alloc(gfp_t gfp_flags);
  27
  28extern void ceph_pagelist_release(struct ceph_pagelist *pl);
  29
  30extern int ceph_pagelist_append(struct ceph_pagelist *pl, const void *d, size_t l);
  31
  32extern int ceph_pagelist_reserve(struct ceph_pagelist *pl, size_t space);
  33
  34extern int ceph_pagelist_free_reserve(struct ceph_pagelist *pl);
  35
  36extern void ceph_pagelist_set_cursor(struct ceph_pagelist *pl,
  37                                     struct ceph_pagelist_cursor *c);
  38
  39extern int ceph_pagelist_truncate(struct ceph_pagelist *pl,
  40                                  struct ceph_pagelist_cursor *c);
  41
  42static inline int ceph_pagelist_encode_64(struct ceph_pagelist *pl, u64 v)
  43{
  44        __le64 ev = cpu_to_le64(v);
  45        return ceph_pagelist_append(pl, &ev, sizeof(ev));
  46}
  47static inline int ceph_pagelist_encode_32(struct ceph_pagelist *pl, u32 v)
  48{
  49        __le32 ev = cpu_to_le32(v);
  50        return ceph_pagelist_append(pl, &ev, sizeof(ev));
  51}
  52static inline int ceph_pagelist_encode_16(struct ceph_pagelist *pl, u16 v)
  53{
  54        __le16 ev = cpu_to_le16(v);
  55        return ceph_pagelist_append(pl, &ev, sizeof(ev));
  56}
  57static inline int ceph_pagelist_encode_8(struct ceph_pagelist *pl, u8 v)
  58{
  59        return ceph_pagelist_append(pl, &v, 1);
  60}
  61static inline int ceph_pagelist_encode_string(struct ceph_pagelist *pl,
  62                                              char *s, u32 len)
  63{
  64        int ret = ceph_pagelist_encode_32(pl, len);
  65        if (ret)
  66                return ret;
  67        if (len)
  68                return ceph_pagelist_append(pl, s, len);
  69        return 0;
  70}
  71
  72#endif
  73