From: Xuehan Xu <xuxuehan@qianxin.com>
Date: Mon, 3 Mar 2025 10:07:25 +0000 (+0800)
Subject: crimson/os/seastore/linked_tree_node: set reserved_ptr to an 8-byte
X-Git-Tag: v20.3.0~433^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=3303f86fdd50bf4f57447ca76952bceb45c00ee4;p=ceph.git

crimson/os/seastore/linked_tree_node: set reserved_ptr to an 8-byte
aligned address

Maybe we shouldn't be using an instant integer as the invalid pointer.

Fixes: https://tracker.ceph.com/issues/70202
Signed-off-by: Xuehan Xu <xuxuehan@qianxin.com>
---

diff --git a/src/crimson/os/seastore/linked_tree_node.h b/src/crimson/os/seastore/linked_tree_node.h
index 4f8e52bea17c..76be226ebb72 100644
--- a/src/crimson/os/seastore/linked_tree_node.h
+++ b/src/crimson/os/seastore/linked_tree_node.h
@@ -217,7 +217,10 @@ protected:
 // indirect mapping.
 template <typename T, typename node_key_t>
 inline BaseChildNode<T, node_key_t>* get_reserved_ptr() {
-  return (BaseChildNode<T, node_key_t>*)0x1;
+  //TODO: using instant integers as invalid pointers may
+  //	  not be a good practice.
+  constexpr uint64_t reserved_ptr = std::numeric_limits<size_t>::max() - 15;
+  return (BaseChildNode<T, node_key_t>*)reserved_ptr;
 }
 
 template <typename T, typename node_key_t>