Move server_set_status and server_clear_status to monitor

The operation goes through monitor code so should be in the according file.

include/maxscale/server.hh

@@ -528,26 +528,3 @@ private:
     maxbase::EMAverage m_response_time;         /**< Response time calculations for this server */
     std::mutex         m_average_write_mutex;   /**< Protects response time from concurrent writing */
 };
-
-namespace maxscale
-{
-
-/**
- * Set a status bit in the server. This should not be called from within a monitor. If the server is
- * monitored, only set the pending bit.
- *
- * @param bit           The bit to set for the server
- * @param errmsg_out    Error output
- */
-bool server_set_status(SERVER* server, int bit, std::string* errmsg_out = NULL);
-
-/**
- * Clear a status bit in the server under a lock. This ensures synchronization
- * with the server monitor thread. Calling this inside the monitor will likely
- * cause a deadlock. If the server is monitored, only clear the pending bit.
- *
- * @param bit           The bit to clear for the server
- * @param errmsg_out    Error output
- */
-bool server_clear_status(SERVER* server, int bit, std::string* errmsg_out = NULL);
-}

server/core/internal/monitormanager.hh

@@ -139,6 +139,26 @@ public:
 
     static bool create_monitor_config(const mxs::Monitor* monitor, const char* filename);
 
+    /**
+     * Set a status bit in the server. If the server is monitored, only some bits can be modified,
+     * and the modification goes through the monitor.
+     *
+     * @param bit           The bit to set for the server
+     * @param errmsg_out    Error output
+     * @return              True on success
+     */
+    static bool set_server_status(SERVER* srv, int bit, std::string* errmsg_out = NULL);
+
+    /**
+     * Clear a status bit in the server. If the server is monitored, only some bits can be modified,
+     * and the modification goes through the monitor.
+     *
+     * @param bit           The bit to clear for the server
+     * @param errmsg_out    Error output
+     * @return              True on success
+     */
+    static bool clear_server_status(SERVER* srv, int bit, std::string* errmsg_out);
+
     /**
      * Waits until all running monitors have advanced one tick.
      */

server/core/monitormanager.cc

@@ -474,3 +474,39 @@ json_t* MonitorManager::monitor_relations_to_server(const SERVER* server, const
 
     return rel;
 }
+
+bool MonitorManager::set_server_status(SERVER* srv, int bit, string* errmsg_out)
+{
+    mxb_assert(Monitor::is_admin_thread());
+    bool written = false;
+    Monitor* mon = MonitorManager::server_is_monitored(srv);
+    if (mon)
+    {
+        written = mon->set_server_status(srv, bit, errmsg_out);
+    }
+    else
+    {
+        /* Set the bit directly */
+        srv->set_status(bit);
+        written = true;
+    }
+    return written;
+}
+
+bool MonitorManager::clear_server_status(SERVER* srv, int bit, string* errmsg_out)
+{
+    mxb_assert(Monitor::is_admin_thread());
+    bool written = false;
+    Monitor* mon = MonitorManager::server_is_monitored(srv);
+    if (mon)
+    {
+        written = mon->clear_server_status(srv, bit, errmsg_out);
+    }
+    else
+    {
+        /* Clear bit directly */
+        srv->clear_status(bit);
+        written = true;
+    }
+    return written;
+}

server/core/resource.cc

@@ -794,7 +794,7 @@ HttpResponse cb_set_server(const HttpRequest& request)
     if (opt)
     {
         string errmsg;
-        if (mxs::server_set_status(server, opt, &errmsg))
+        if (MonitorManager::set_server_status(server, opt, &errmsg))
         {
             if (status_is_in_maint(opt) && request.get_option(CN_FORCE) == CN_YES)
             {
@@ -821,7 +821,7 @@ HttpResponse cb_clear_server(const HttpRequest& request)
     if (opt)
     {
         string errmsg;
-        if (mxs::server_clear_status(server, opt, &errmsg))
+        if (MonitorManager::clear_server_status(server, opt, &errmsg))
         {
             return HttpResponse(MHD_HTTP_NO_CONTENT);
         }

server/core/server.cc

@@ -922,46 +922,6 @@ bool Server::serialize() const
     return rval;
 }
 
-bool mxs::server_set_status(SERVER* srv, int bit, string* errmsg_out)
-{
-    bool written = false;
-    /* First check if the server is monitored. This isn't done under a lock
-     * but the race condition cannot cause significant harm. Monitors are never
-     * freed so the pointer stays valid. */
-    Monitor* mon = MonitorManager::server_is_monitored(srv);
-    if (mon)
-    {
-        written = mon->set_server_status(srv, bit, errmsg_out);
-    }
-    else
-    {
-        /* Set the bit directly */
-        srv->set_status(bit);
-        written = true;
-    }
-
-    return written;
-}
-
-bool mxs::server_clear_status(SERVER* srv, int bit, string* errmsg_out)
-{
-    // See server_set_status().
-    bool written = false;
-    Monitor* mon = MonitorManager::server_is_monitored(srv);
-    if (mon)
-    {
-        written = mon->clear_server_status(srv, bit, errmsg_out);
-    }
-    else
-    {
-        /* Clear bit directly */
-        srv->clear_status(bit);
-        written = true;
-    }
-
-    return written;
-}
-
 bool SERVER::is_mxs_service()
 {
     bool rval = false;

server/modules/protocol/MySQL/mariadbbackend/mysql_backend.cc

@@ -24,6 +24,8 @@
 #include <maxscale/router.hh>
 #include <maxscale/server.hh>
 #include <maxscale/utils.h>
+// For setting server status through monitor
+#include "../../../../core/internal/monitormanager.hh"
 
 /*
  * MySQL Protocol module for handling the protocol between the gateway
@@ -340,10 +342,16 @@ static void handle_error_response(DCB* dcb, GWBUF* buffer)
               errcode,
               bufstr);
 
-    /** If the error is ER_HOST_IS_BLOCKED put the server into maintenace mode.
+    /** If the error is ER_HOST_IS_BLOCKED put the server into maintenance mode.
      * This will prevent repeated authentication failures. */
     if (errcode == ER_HOST_IS_BLOCKED)
     {
+        auto main_worker = mxs::RoutingWorker::get(mxs::RoutingWorker::MAIN);
+        auto target_server = dcb->server;
+        main_worker->execute([target_server]() {
+            MonitorManager::set_server_status(target_server, SERVER_MAINT);
+        }, mxb::Worker::EXECUTE_AUTO);
+
         MXS_ERROR("Server %s has been put into maintenance mode due to the server blocking connections "
                   "from MaxScale. Run 'mysqladmin -h %s -P %d flush-hosts' on this server before taking "
                   "this server out of maintenance mode. To avoid this problem in the future, set "
@@ -351,8 +359,6 @@ static void handle_error_response(DCB* dcb, GWBUF* buffer)
                   dcb->server->name(),
                   dcb->server->address,
                   dcb->server->port);
-
-        mxs::server_set_status(dcb->server, SERVER_MAINT);
     }
     else if (errcode == ER_ACCESS_DENIED_ERROR
              || errcode == ER_DBACCESS_DENIED_ERROR

server/modules/routing/cli/debugcmd.cc

@@ -2525,7 +2525,7 @@ static void set_server(DCB* dcb, Server* server, char* bit)
     if ((bitvalue = SERVER::status_from_string(bit)) != 0)
     {
         std::string errmsg;
-        if (!mxs::server_set_status(server, bitvalue, &errmsg))
+        if (!MonitorManager::set_server_status(server, bitvalue, &errmsg))
         {
             dcb_printf(dcb, "%s\n", errmsg.c_str());
         }
@@ -2551,7 +2551,7 @@ static void clear_server(DCB* dcb, Server* server, char* bit)
     if ((bitvalue = SERVER::status_from_string(bit)) != 0)
     {
         std::string errmsg;
-        if (!mxs::server_clear_status(server, bitvalue, &errmsg))
+        if (!MonitorManager::clear_server_status(server, bitvalue, &errmsg))
         {
             dcb_printf(dcb, "%s", errmsg.c_str());
         }

server/modules/routing/maxinfo/maxinfo_exec.cc

@@ -325,7 +325,7 @@ void exec_set_server(DCB* dcb, MAXINFO_TREE* tree)
         if (status != 0)
         {
             std::string errmsgs;
-            if (mxs::server_set_status(server, status, &errmsgs))
+            if (MonitorManager::set_server_status(server, status, &errmsgs))
             {
                 maxinfo_send_ok(dcb);
             }
@@ -412,7 +412,7 @@ void exec_clear_server(DCB* dcb, MAXINFO_TREE* tree)
         if (status != 0)
         {
             std::string errmsgs;
-            if (mxs::server_clear_status(server, status, &errmsgs))
+            if (MonitorManager::clear_server_status(server, status, &errmsgs))
             {
                 maxinfo_send_ok(dcb);
             }