src/journal/mmap-cache.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   Copyright 2012 Lennart Poettering
   6 ***/
   7
   8 #include <stdbool.h>
   9 #include <sys/stat.h>
  10
  11 /* One context per object type, plus one of the header, plus one "additional" one */
  12 #define MMAP_CACHE_MAX_CONTEXTS 9
  13
  14 typedef struct MMapCache MMapCache;
  15 typedef struct MMapFileDescriptor MMapFileDescriptor;
  16
  17 MMapCache* mmap_cache_new(void);
  18 MMapCache* mmap_cache_ref(MMapCache *m);
  19 MMapCache* mmap_cache_unref(MMapCache *m);
  20
  21 int mmap_cache_get(
  22         MMapCache *m,
  23         MMapFileDescriptor *f,
  24         int prot,
  25         unsigned context,
  26         bool keep_always,
  27         uint64_t offset,
  28         size_t size,
  29         struct stat *st,
  30         void **ret,
  31         size_t *ret_size);
  32 MMapFileDescriptor * mmap_cache_add_fd(MMapCache *m, int fd);
  33 void mmap_cache_free_fd(MMapCache *m, MMapFileDescriptor *f);
  34
  35 unsigned mmap_cache_get_hit(MMapCache *m);
  36 unsigned mmap_cache_get_missed(MMapCache *m);
  37
  38 bool mmap_cache_got_sigbus(MMapCache *m, MMapFileDescriptor *f);