fs: btrfs: Crossport rbtree-utils from btrfs-progs
This is needed for incoming extent-cache infrastructure.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
diff --git a/fs/btrfs/common/rbtree-utils.c b/fs/btrfs/common/rbtree-utils.c
new file mode 100644
index 0000000..7a7d7e8
--- /dev/null
+++ b/fs/btrfs/common/rbtree-utils.c
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2014 Facebook. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/errno.h>
+#include "rbtree-utils.h"
+
+int rb_insert(struct rb_root *root, struct rb_node *node,
+ rb_compare_nodes comp)
+{
+ struct rb_node **p = &root->rb_node;
+ struct rb_node *parent = NULL;
+ int ret;
+
+ while(*p) {
+ parent = *p;
+
+ ret = comp(parent, node);
+ if (ret < 0)
+ p = &(*p)->rb_left;
+ else if (ret > 0)
+ p = &(*p)->rb_right;
+ else
+ return -EEXIST;
+ }
+
+ rb_link_node(node, parent, p);
+ rb_insert_color(node, root);
+ return 0;
+}
+
+struct rb_node *rb_search(struct rb_root *root, void *key, rb_compare_keys comp,
+ struct rb_node **next_ret)
+{
+ struct rb_node *n = root->rb_node;
+ struct rb_node *parent = NULL;
+ int ret = 0;
+
+ while(n) {
+ parent = n;
+
+ ret = comp(n, key);
+ if (ret < 0)
+ n = n->rb_left;
+ else if (ret > 0)
+ n = n->rb_right;
+ else
+ return n;
+ }
+
+ if (!next_ret)
+ return NULL;
+
+ if (parent && ret > 0)
+ parent = rb_next(parent);
+
+ *next_ret = parent;
+ return NULL;
+}
+
+void rb_free_nodes(struct rb_root *root, rb_free_node free_node)
+{
+ struct rb_node *node;
+
+ while ((node = rb_first(root))) {
+ rb_erase(node, root);
+ free_node(node);
+ }
+}