+++ /dev/null
-#ifndef CEPH_CRUSH_MAPPER_H
-#define CEPH_CRUSH_MAPPER_H
-
-/*
- * CRUSH functions for find rules and then mapping an input to an
- * output set.
- *
- * LGPL2
- */
-
-#include "crush.h"
-
-extern int crush_find_rule(const struct crush_map *map, int ruleset, int type, int size);
-/** @ingroup API
- *
- * Map __x__ to __result_max__ items and store them in the __result__
- * array. The mapping is done by following each step of the rule
- * __ruleno__. See crush_make_rule(), crush_rule_set_step() and
- * crush_add_rule() for more information on how the rules are created,
- * populated and added to the crush __map__.
- *
- * The return value is the the number of items in the __result__
- * array. If the caller asked for __result_max__ items and the return
- * value is X where X < __result_max__, the content of __result[0,X[__
- * is defined but the content of __result[X,result_max[__ is
- * undefined. For example:
- *
- * crush_do_rule(map, ruleno=1, x=1, result, result_max=3,...) == 1
- * result[0] is set
- * result[1] is undefined
- * result[2] is undefined
- *
- * An entry in the __result__ array is either an item in the crush
- * __map__ or ::CRUSH_ITEM_NONE if no item was found. For example:
- *
- * crush_do_rule(map, ruleno=1, x=1, result, result_max=4,...) == 2
- * result[0] is CRUSH_ITEM_NONE
- * result[1] is item number 5
- * result[2] is undefined
- * result[3] is undefined
- *
- * The __weight__ array contains the probabilities that a leaf is
- * ignored even if it is selected. It is a 16.16 fixed point
- * number in the range [0x00000,0x10000]. The lower the value, the
- * more often the leaf is ignored. For instance:
- *
- * - weight[leaf] == 0x00000 == 0.0 always ignore
- * - weight[leaf] == 0x10000 == 1.0 never ignore
- * - weight[leaf] == 0x08000 == 0.5 ignore 50% of the time
- * - weight[leaf] == 0x04000 == 0.25 ignore 75% of the time
- * - etc.
- *
- * During mapping, each leaf is checked against the __weight__ array,
- * using the leaf as an index. If there is no entry in __weight__ for
- * the leaf, it is ignored. If there is an entry, the leaf will be
- * ignored some of the time, depending on the probability.
- *
- * The __cwin__ argument must be set as follows:
- *
- * char __cwin__[crush_work_size(__map__, __result_max__)];
- * crush_init_workspace(__map__, __cwin__);
- *
- * @param map the crush_map
- * @param ruleno a positive integer < __CRUSH_MAX_RULES__
- * @param x the value to map to __result_max__ items
- * @param result an array of items of size __result_max__
- * @param result_max the size of the __result__ array
- * @param weights an array of weights of size __weight_max__
- * @param weight_max the size of the __weights__ array
- * @param cwin must be an char array initialized by crush_init_workspace
- * @param choose_args weights and ids for each known bucket
- *
- * @return 0 on error or the size of __result__ on success
- */
-extern int crush_do_rule(const struct crush_map *map,
- int ruleno,
- int x, int *result, int result_max,
- const __u32 *weights, int weight_max,
- void *cwin, const struct crush_choose_arg *choose_args);
-
-/* Returns the exact amount of workspace that will need to be used
- for a given combination of crush_map and result_max. The caller can
- then allocate this much on its own, either on the stack, in a
- per-thread long-lived buffer, or however it likes. */
-
-static inline size_t crush_work_size(const struct crush_map *map,
- int result_max) {
- return map->working_size + result_max * 3 * sizeof(__u32);
-}
-
-extern void crush_init_workspace(const struct crush_map *m, void *v);
-
-#endif
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