mapper.h

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef CEPH_CRUSH_MAPPER_H
 3#define CEPH_CRUSH_MAPPER_H
 4
 5/*
 6 * CRUSH functions for find rules and then mapping an input to an
 7 * output set.
 8 *
 9 * LGPL2
10 */
11
12#include "crush.h"
13
14extern int crush_find_rule(const struct crush_map *map, int ruleset, int type, int size);
15int crush_do_rule(const struct crush_map *map,
16		  int ruleno, int x, int *result, int result_max,
17		  const __u32 *weight, int weight_max,
18		  void *cwin, const struct crush_choose_arg *choose_args);
19
20/*
21 * Returns the exact amount of workspace that will need to be used
22 * for a given combination of crush_map and result_max. The caller can
23 * then allocate this much on its own, either on the stack, in a
24 * per-thread long-lived buffer, or however it likes.
25 */
26static inline size_t crush_work_size(const struct crush_map *map,
27				     int result_max)
28{
29	return map->working_size + result_max * 3 * sizeof(__u32);
30}
31
32void crush_init_workspace(const struct crush_map *map, void *v);
33
34#endif