include/linux/crush/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
  14 extern int crush_find_rule(const struct crush_map *map, int ruleset, int type, int size);
  15 int 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  */
  26 static 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
  32 void crush_init_workspace(const struct crush_map *map, void *v);
  33
  34 #endif