Rebase children of the "inverse" child when it is removed, change /index/image/%s keys during metadata ops

src/cli.cpp

@@ -95,25 +95,13 @@ void cli_tool_t::change_parent(inode_t cur, inode_t new_parent)
         fprintf(stderr, "Inode 0x%lx disappeared\n", cur);
         exit(1);
     }
-    inode_config_t *cur_cfg = &cur_cfg_it->second;
+    inode_config_t new_cfg = cur_cfg_it->second;
-    std::string cur_name = cur_cfg->name;
+    std::string cur_name = new_cfg.name;
     std::string cur_cfg_key = base64_encode(cli->st_cli.etcd_prefix+
         "/config/inode/"+std::to_string(INODE_POOL(cur))+
         "/"+std::to_string(INODE_NO_POOL(cur)));
-    json11::Json::object cur_cfg_json = json11::Json::object {
+    new_cfg.parent_id = new_parent;
-        { "name", cur_cfg->name },
+    json11::Json::object cur_cfg_json = cli->st_cli.serialize_inode_cfg(&new_cfg);
-        { "size", cur_cfg->size },
-    };
-    if (new_parent)
-    {
-        if (INODE_POOL(cur) != INODE_POOL(new_parent))
-            cur_cfg_json["parent_pool"] = (uint64_t)INODE_POOL(new_parent);
-        cur_cfg_json["parent_id"] = (uint64_t)INODE_NO_POOL(new_parent);
-    }
-    if (cur_cfg->readonly)
-    {
-        cur_cfg_json["readonly"] = true;
-    }
     waiting++;
     cli->st_cli.etcd_txn(json11::Json::object {
         { "compare", json11::Json::array {
@@ -121,7 +109,7 @@ void cli_tool_t::change_parent(inode_t cur, inode_t new_parent)
                 { "target", "MOD" },
                 { "key", cur_cfg_key },
                 { "result", "LESS" },
-                { "mod_revision", cur_cfg->mod_revision+1 },
+                { "mod_revision", new_cfg.mod_revision+1 },
             },
         } },
         { "success", json11::Json::array {

src/cli_snap_rm.cpp

@@ -138,7 +138,8 @@ resume_5:
                 return;
             }
             cb = NULL;
-            // Delete "inverse" child metadata and rename parent over it
+            // Delete "inverse" child metadata, rename parent over it,
+            // and also change parent links of the previous "inverse" child
             rename_inverse_parent();
             state = 6;
 resume_6:
@@ -345,47 +346,76 @@ resume_9:
             "/config/inode/"+std::to_string(INODE_POOL(inverse_parent))+
             "/"+std::to_string(INODE_NO_POOL(inverse_parent))
         );
-        json11::Json::object new_cfg = json11::Json::object {
+        // Fill new configuration
-            { "name", child_cfg->name },
+        inode_config_t new_cfg = *child_cfg;
-            { "size", child_cfg->size },
+        new_cfg.num = target_cfg->num;
+        new_cfg.parent_id = new_parent;
+        json11::Json::array cmp = json11::Json::array {
+            json11::Json::object {
+                { "target", "MOD" },
+                { "key", child_cfg_key },
+                { "result", "LESS" },
+                { "mod_revision", child_cfg->mod_revision+1 },
+            },
+            json11::Json::object {
+                { "target", "MOD" },
+                { "key", target_cfg_key },
+                { "result", "LESS" },
+                { "mod_revision", target_cfg->mod_revision+1 },
+            },
         };
-        if (new_parent)
+        json11::Json::array txn = json11::Json::array {
+            json11::Json::object {
+                { "request_delete_range", json11::Json::object {
+                    { "key", child_cfg_key },
+                } },
+            },
+            json11::Json::object {
+                { "request_put", json11::Json::object {
+                    { "key", target_cfg_key },
+                    { "value", base64_encode(json11::Json(parent->cli->st_cli.serialize_inode_cfg(&new_cfg)).dump()) },
+                } },
+            },
+            json11::Json::object {
+                { "request_put", json11::Json::object {
+                    { "key", base64_encode(parent->cli->st_cli.etcd_prefix+"/index/image/"+child_cfg->name) },
+                    { "value", base64_encode(json11::Json({
+                        { "id", INODE_NO_POOL(inverse_parent) },
+                        { "pool_id", (uint64_t)INODE_POOL(inverse_parent) },
+                    }).dump()) },
+                } },
+            },
+        };
+        // Reparent children of inverse_child
+        for (auto & cp: parent->cli->st_cli.inode_config)
         {
-            if (INODE_POOL(inverse_parent) != INODE_POOL(new_parent))
+            if (cp.second.parent_id == child_cfg->num)
-                new_cfg["parent_pool"] = (uint64_t)INODE_POOL(new_parent);
+            {
-            new_cfg["parent_id"] = (uint64_t)INODE_NO_POOL(new_parent);
+                auto cp_cfg = cp.second;
-        }
+                cp_cfg.parent_id = inverse_parent;
-        if (child_cfg->readonly)
+                auto cp_key = base64_encode(
-        {
+                    parent->cli->st_cli.etcd_prefix+
-            new_cfg["readonly"] = true;
+                    "/config/inode/"+std::to_string(INODE_POOL(cp.second.num))+
+                    "/"+std::to_string(INODE_NO_POOL(cp.second.num))
+                );
+                cmp.push_back(json11::Json::object {
+                    { "target", "MOD" },
+                    { "key", cp_key },
+                    { "result", "LESS" },
+                    { "mod_revision", cp.second.mod_revision+1 },
+                });
+                txn.push_back(json11::Json::object {
+                    { "request_put", json11::Json::object {
+                        { "key", cp_key },
+                        { "value", base64_encode(json11::Json(parent->cli->st_cli.serialize_inode_cfg(&cp_cfg)).dump()) },
+                    } },
+                });
+            }
         }
         parent->waiting++;
         parent->cli->st_cli.etcd_txn(json11::Json::object {
-            { "compare", json11::Json::array {
+            { "compare", cmp },
-                json11::Json::object {
+            { "success", txn },
-                    { "target", "MOD" },
-                    { "key", child_cfg_key },
-                    { "result", "LESS" },
-                    { "mod_revision", child_cfg->mod_revision+1 },
-                },
-                json11::Json::object {
-                    { "target", "MOD" },
-                    { "key", target_cfg_key },
-                    { "result", "LESS" },
-                    { "mod_revision", target_cfg->mod_revision+1 },
-                },
-            } },
-            { "success", json11::Json::array {
-                json11::Json::object {
-                    { "request_delete_range", json11::Json::object {
-                        { "key", child_cfg_key },
-                    } },
-                    { "request_put", json11::Json::object {
-                        { "key", target_cfg_key },
-                        { "value", base64_encode(json11::Json(new_cfg).dump()) },
-                    } }
-                },
-            } },
         }, ETCD_SLOW_TIMEOUT, [this, target_name, child_name](std::string err, json11::Json res)
         {
             parent->waiting--;
@@ -396,7 +426,10 @@ resume_9:
             }
             if (!res["succeeded"].bool_value())
             {
-                fprintf(stderr, "Layer %s or %s configuration was modified during renaming\n", target_name.c_str(), child_name.c_str());
+                fprintf(
+                    stderr, "Parent (%s), child (%s), or one of its children"
+                    " configuration was modified during rename\n", target_name.c_str(), child_name.c_str()
+                );
                 exit(1);
             }
             printf("Layer %s renamed to %s\n", target_name.c_str(), child_name.c_str());
@@ -414,9 +447,11 @@ resume_9:
         }
         inode_config_t *cur_cfg = &cur_cfg_it->second;
         std::string cur_name = cur_cfg->name;
-        std::string cur_cfg_key = base64_encode(parent->cli->st_cli.etcd_prefix+
+        std::string cur_cfg_key = base64_encode(
+            parent->cli->st_cli.etcd_prefix+
             "/config/inode/"+std::to_string(INODE_POOL(cur))+
-            "/"+std::to_string(INODE_NO_POOL(cur)));
+            "/"+std::to_string(INODE_NO_POOL(cur))
+        );
         parent->waiting++;
         parent->cli->st_cli.etcd_txn(json11::Json::object {
             { "compare", json11::Json::array {
@@ -432,6 +467,9 @@ resume_9:
                     { "request_delete_range", json11::Json::object {
                         { "key", cur_cfg_key },
                     } },
+                    { "request_delete_range", json11::Json::object {
+                        { "key", base64_encode(parent->cli->st_cli.etcd_prefix+"/index/image/"+cur_name) },
+                    } },
                 },
             } },
         }, ETCD_SLOW_TIMEOUT, [this, cur_name](std::string err, json11::Json res)

src/etcd_state_client.cpp

@@ -765,3 +765,22 @@ void etcd_state_client_t::close_watch(inode_watch_t* watch)
     }
     delete watch;
 }
+
+json11::Json::object & etcd_state_client_t::serialize_inode_cfg(inode_config_t *cfg)
+{
+    json11::Json::object new_cfg = json11::Json::object {
+        { "name", cfg->name },
+        { "size", cfg->size },
+    };
+    if (cfg->parent_id)
+    {
+        if (INODE_POOL(cfg->num) != INODE_POOL(cfg->parent_id))
+            new_cfg["parent_pool"] = (uint64_t)INODE_POOL(cfg->parent_id);
+        new_cfg["parent_id"] = (uint64_t)INODE_NO_POOL(cfg->parent_id);
+    }
+    if (cfg->readonly)
+    {
+        new_cfg["readonly"] = true;
+    }
+    return new_cfg;
+}

src/etcd_state_client.h

@@ -99,6 +99,7 @@ public:
     std::function<void(pool_id_t, pg_num_t)> on_change_pg_history_hook;
     std::function<void(osd_num_t)> on_change_osd_state_hook;
 
+    json11::Json::object & serialize_inode_cfg(inode_config_t *cfg);
     etcd_kv_t parse_etcd_kv(const json11::Json & kv_json);
     void etcd_call(std::string api, json11::Json payload, int timeout, std::function<void(std::string, json11::Json)> callback);
     void etcd_txn(json11::Json txn, int timeout, std::function<void(std::string, json11::Json)> callback);