include/linux/crush/mapper.h

   1 #ifndef CEPH_CRUSH_MAPPER_H
   2 #define CEPH_CRUSH_MAPPER_H
   3
   4 /*
   5  * CRUSH functions for find rules and then mapping an input to an
   6  * output set.
   7  *
   8  * LGPL2
   9  */
  10
  11 #include "crush.h"
  12
  13 extern int crush_find_rule(const struct crush_map *map, int ruleset, int type, int size);
  14 extern int crush_do_rule(const struct crush_map *map,
  15                          int ruleno,
  16                          int x, int *result, int result_max,
  17                          const __u32 *weights, int weight_max,
  18                          void *cwin);
  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