btrfs-progs: extent-tree: Introduce function to find the first overlapping extent

Introduce a new function, btrfs_search_overlap_extent() to find the first
overlapping extent.

It's useful for later btrfs-convert rework.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/ctree.c b/ctree.c
index 6875bb48..a98ad185 100644
--- a/ctree.c
+++ b/ctree.c
@@ -2951,3 +2951,27 @@ int btrfs_previous_extent_item(struct btrfs_root *root,
 	}
 	return 1;
 }
+
+/*
+ * Search in extent tree to found next meta/data extent
+ * Caller needs to check for no-hole or skinny metadata features.
+ */
+int btrfs_next_extent_item(struct btrfs_root *root,
+			struct btrfs_path *path, u64 max_objectid)
+{
+	struct btrfs_key found_key;
+	int ret;
+
+	while (1) {
+		ret = btrfs_next_item(root, path);
+		if (ret)
+			return ret;
+		btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+				      path->slots[0]);
+		if (found_key.objectid > max_objectid)
+			return 1;
+		if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
+		    found_key.type == BTRFS_METADATA_ITEM_KEY)
+		return 0;
+	}
+}