filters/cache/cache.h

   1 /* nbdkit
   2  * Copyright Red Hat
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   9  * notice, this list of conditions and the following disclaimer.
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  11  * * Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
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  22  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
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  31  */
  32
  33 #ifndef NBDKIT_CACHE_H
  34 #define NBDKIT_CACHE_H
  35
  36 #include <fcntl.h>
  37
  38 /* Caching mode. */
  39 extern enum cache_mode {
  40   CACHE_MODE_WRITEBACK,
  41   CACHE_MODE_WRITETHROUGH,
  42   CACHE_MODE_UNSAFE,
  43 } cache_mode;
  44
  45 /* Size of a block in the cache. */
  46 extern unsigned blksize;
  47
  48 /* Minimum block size (cache-min-block-size parameter). */
  49 extern unsigned min_block_size;
  50
  51 /* Maximum size of the cache and high/low thresholds. */
  52 extern int64_t max_size;
  53 extern unsigned hi_thresh, lo_thresh;
  54
  55 /* Cache on read mode. */
  56 extern enum cor_mode {
  57   COR_OFF,
  58   COR_ON,
  59   COR_PATH,
  60 } cor_mode;
  61 extern const char *cor_path;
  62 extern bool cache_on_read (void);
  63
  64 #endif /* NBDKIT_CACHE_H */