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/* nbdkit
* Copyright Red Hat
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of Red Hat nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef NBDKIT_CACHE_H
#define NBDKIT_CACHE_H
#include <fcntl.h>
/* Caching mode. */
extern enum cache_mode {
CACHE_MODE_WRITEBACK,
CACHE_MODE_WRITETHROUGH,
CACHE_MODE_UNSAFE,
} cache_mode;
/* Size of a block in the cache. */
extern unsigned blksize;
/* Minimum block size (cache-min-block-size parameter). */
extern unsigned min_block_size;
/* Maximum size of the cache and high/low thresholds. */
extern int64_t max_size;
extern unsigned hi_thresh, lo_thresh;
/* Cache on read mode. */
extern enum cor_mode {
COR_OFF,
COR_ON,
COR_PATH,
} cor_mode;
extern const char *cor_path;
extern bool cache_on_read (void);
#endif /* NBDKIT_CACHE_H */
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