add dirty ring command

hmp-commands.hx

@@ -1862,3 +1862,17 @@ SRST
   List event channels in the guest
 ERST
 #endif
+
+   {
+       .name       = "dirtyring",
+       .args_type  = "",
+       .params     = "",
+       .help       = "",
+       .cmd        = hmp_dirtyring,
+   },
+
+SRST
+``dirtyring``
+  Dirty ring
+ERST
+

include/monitor/hmp.h

@@ -183,3 +183,5 @@ void hmp_info_mtree(Monitor *mon, const QDict *qdict);
 void hmp_info_cryptodev(Monitor *mon, const QDict *qdict);
 
 #endif
+
+void hmp_dirtyring(Monitor *mon, const QDict *qdict);

linux-user/main.c

@@ -672,6 +672,7 @@ static int parse_args(int argc, char **argv)
 
 int main(int argc, char **argv, char **envp)
 {
+    printf("Dirty ring QEMU\n");
     struct target_pt_regs regs1, *regs = &regs1;
     struct image_info info1, *info = &info1;
     struct linux_binprm bprm;

migration/migration-hmp-cmds.c

@@ -28,6 +28,7 @@
 #include "qemu/error-report.h"
 #include "qemu/sockets.h"
 #include "sysemu/runstate.h"
+#include "sysemu/kvm.h"
 #include "ui/qemu-spice.h"
 #include "sysemu/sysemu.h"
 #include "options.h"
@@ -235,6 +236,10 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
                        info->vfio->transferred >> 10);
     }
 
+    monitor_printf(mon, "kvm_dirty_ring_enabled: %s\n",
+        kvm_dirty_ring_enabled() ? "on" : "off");
+
+
     qapi_free_MigrationInfo(info);
 }
 

monitor/hmp-cmds.c

@@ -28,6 +28,7 @@
 #include "hw/intc/intc.h"
 #include "qemu/log.h"
 #include "sysemu/sysemu.h"
+#include "sysemu/kvm.h"
 
 bool hmp_handle_error(Monitor *mon, Error *err)
 {
@@ -443,3 +444,12 @@ void hmp_info_mtree(Monitor *mon, const QDict *qdict)
 
     mtree_info(flatview, dispatch_tree, owner, disabled);
 }
+
+void hmp_dirtyring(Monitor *mon, const QDict *qdict)
+{
+    if (kvm_dirty_ring_enabled()) {
+        printf("Dirty ring enabled.\n");
+    } else {
+        printf("Dirty ring disabled.\n");
+    }
+}

monitor/qmp-cmds.c

@@ -209,3 +209,8 @@ static void __attribute__((__constructor__)) monitor_init_qmp_commands(void)
                          qmp_marshal_qmp_capabilities,
                          QCO_ALLOW_PRECONFIG, 0);
 }
+
+void qmp_dirtyring(Error **errp)
+{
+    printf("Hello, world!\n");
+}

qapi/misc.json

@@ -605,3 +605,10 @@
 { 'event': 'VFU_CLIENT_HANGUP',
   'data': { 'vfu-id': 'str', 'vfu-qom-path': 'str',
             'dev-id': 'str', 'dev-qom-path': 'str' } }
+
+##
+# @dirtyring:
+#
+# Since: 9.0
+##
+{ 'command': 'dirtyring' }