aboutsummaryrefslogtreecommitdiff
path: root/fs/ceph/crush/crush.c
blob: fabd302e5779c0188b55916be81d7913dce84105 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151

#ifdef __KERNEL__
# include <linux/slab.h>
#else
# include <stdlib.h>
# include <assert.h>
# define kfree(x) do { if (x) free(x); } while (0)
# define BUG_ON(x) assert(!(x))
#endif

#include "crush.h"

const char *crush_bucket_alg_name(int alg)
{
	switch (alg) {
	case CRUSH_BUCKET_UNIFORM: return "uniform";
	case CRUSH_BUCKET_LIST: return "list";
	case CRUSH_BUCKET_TREE: return "tree";
	case CRUSH_BUCKET_STRAW: return "straw";
	default: return "unknown";
	}
}

/**
 * crush_get_bucket_item_weight - Get weight of an item in given bucket
 * @b: bucket pointer
 * @p: item index in bucket
 */
int crush_get_bucket_item_weight(struct crush_bucket *b, int p)
{
	if (p >= b->size)
		return 0;

	switch (b->alg) {
	case CRUSH_BUCKET_UNIFORM:
		return ((struct crush_bucket_uniform *)b)->item_weight;
	case CRUSH_BUCKET_LIST:
		return ((struct crush_bucket_list *)b)->item_weights[p];
	case CRUSH_BUCKET_TREE:
		if (p & 1)
			return ((struct crush_bucket_tree *)b)->node_weights[p];
		return 0;
	case CRUSH_BUCKET_STRAW:
		return ((struct crush_bucket_straw *)b)->item_weights[p];
	}
	return 0;
}

/**
 * crush_calc_parents - Calculate parent vectors for the given crush map.
 * @map: crush_map pointer
 */
void crush_calc_parents(struct crush_map *map)
{
	int i, b, c;

	for (b = 0; b < map->max_buckets; b++) {
		if (map->buckets[b] == NULL)
			continue;
		for (i = 0; i < map->buckets[b]->size; i++) {
			c = map->buckets[b]->items[i];
			BUG_ON(c >= map->max_devices ||
			       c < -map->max_buckets);
			if (c >= 0)
				map->device_parents[c] = map->buckets[b]->id;
			else
				map->bucket_parents[-1-c] = map->buckets[b]->id;
		}
	}
}

void crush_destroy_bucket_uniform(struct crush_bucket_uniform *b)
{
	kfree(b->h.perm);
	kfree(b->h.items);
	kfree(b);
}

void crush_destroy_bucket_list(struct crush_bucket_list *b)
{
	kfree(b->item_weights);
	kfree(b->sum_weights);
	kfree(b->h.perm);
	kfree(b->h.items);
	kfree(b);
}

void crush_destroy_bucket_tree(struct crush_bucket_tree *b)
{
	kfree(b->node_weights);
	kfree(b);
}

void crush_destroy_bucket_straw(struct crush_bucket_straw *b)
{
	kfree(b->straws);
	kfree(b->item_weights);
	kfree(b->h.perm);
	kfree(b->h.items);
	kfree(b);
}

void crush_destroy_bucket(struct crush_bucket *b)
{
	switch (b->alg) {
	case CRUSH_BUCKET_UNIFORM:
		crush_destroy_bucket_uniform((struct crush_bucket_uniform *)b);
		break;
	case CRUSH_BUCKET_LIST:
		crush_destroy_bucket_list((struct crush_bucket_list *)b);
		break;
	case CRUSH_BUCKET_TREE:
		crush_destroy_bucket_tree((struct crush_bucket_tree *)b);
		break;
	case CRUSH_BUCKET_STRAW:
		crush_destroy_bucket_straw((struct crush_bucket_straw *)b);
		break;
	}
}

/**
 * crush_destroy - Destroy a crush_map
 * @map: crush_map pointer
 */
void crush_destroy(struct crush_map *map)
{
	int b;

	/* buckets */
	if (map->buckets) {
		for (b = 0; b < map->max_buckets; b++) {
			if (map->buckets[b] == NULL)
				continue;
			crush_destroy_bucket(map->buckets[b]);
		}
		kfree(map->buckets);
	}

	/* rules */
	if (map->rules) {
		for (b = 0; b < map->max_rules; b++)
			kfree(map->rules[b]);
		kfree(map->rules);
	}

	kfree(map->bucket_parents);
	kfree(map->device_parents);
	kfree(map);
}