1 files changed, 151 insertions, 0 deletions

diff --git a/fs/ceph/crush/crush.c b/fs/ceph/crush/crush.c
new file mode 100644
index 000000000000..fabd302e5779
--- /dev/null
+++ b/fs/ceph/crush/crush.c
@@ -0,0 +1,151 @@
+
+#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);
+}
+
+