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-rw-r--r--fs/ceph/crush/crush.c151
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 0000000..fabd302
--- /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);
+}
+
+
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