[Qemu-block] [PATCH] hmp: Add nbd_server_remove to mirror QMP command

[Eric Blake]

Since everything else about the nbd-server-* QMP commands is
accessible from HMP, we might as well make removing an export
available as well.  For now, I went with a bool flag rather
than a mode string for choosing between safe (default) and
hard modes.

Signed-off-by: Eric Blake <address@hidden>
---

Based-on: <address@hidden>
([PATCH v3 0/5] nbd export qmp interface)

 hmp.h           |  1 +
 hmp.c           | 14 +++++++++++---
 hmp-commands.hx | 17 +++++++++++++++++
 3 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/hmp.h b/hmp.h
index a6f56b1f29e..536cb91caa4 100644
--- a/hmp.h
+++ b/hmp.h
@@ -101,6 +101,7 @@ void hmp_sendkey(Monitor *mon, const QDict *qdict);
 void hmp_screendump(Monitor *mon, const QDict *qdict);
 void hmp_nbd_server_start(Monitor *mon, const QDict *qdict);
 void hmp_nbd_server_add(Monitor *mon, const QDict *qdict);
+void hmp_nbd_server_remove(Monitor *mon, const QDict *qdict);
 void hmp_nbd_server_stop(Monitor *mon, const QDict *qdict);
 void hmp_chardev_add(Monitor *mon, const QDict *qdict);
 void hmp_chardev_change(Monitor *mon, const QDict *qdict);
diff --git a/hmp.c b/hmp.c
index 7a64dd59c5c..b3de32d219b 100644
--- a/hmp.c
+++ b/hmp.c
@@ -2226,10 +2226,18 @@ void hmp_nbd_server_add(Monitor *mon, const QDict 
*qdict)
     Error *local_err = NULL;

     qmp_nbd_server_add(device, !!name, name, true, writable, &local_err);
+    hmp_handle_error(mon, &local_err);
+}

-    if (local_err != NULL) {
-        hmp_handle_error(mon, &local_err);
-    }
+void hmp_nbd_server_remove(Monitor *mon, const QDict *qdict)
+{
+    const char *name = qdict_get_str(qdict, "name");
+    bool force = qdict_get_try_bool(qdict, "force", false);
+    Error *err = NULL;
+
+    /* Rely on NBD_SERVER_REMOVE_MODE_SAFE being the default */
+    qmp_nbd_server_remove(name, force, NBD_SERVER_REMOVE_MODE_HARD, &err);
+    hmp_handle_error(mon, &err);
 }

 void hmp_nbd_server_stop(Monitor *mon, const QDict *qdict)
diff --git a/hmp-commands.hx b/hmp-commands.hx
index b8b6fb91848..8a59338bc20 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1565,6 +1565,23 @@ Export a block device through QEMU's NBD server, which 
must be started
 beforehand with @command{nbd_server_start}.  The @option{-w} option makes the
 exported device writable too.  The export name is controlled by @var{name},
 defaulting to @var{device}.
+ETEXI
+
+    {
+        .name       = "nbd_server_remove",
+        .args_type  = "force:-f,name:s",
+        .params     = "nbd_server_remove [-f] name",
+        .help       = "remove an export previously exposed via NBD",
+        .cmd        = hmp_nbd_server_remove,
+    },
+STEXI
address@hidden nbd_server_remove [-f] @var{name}
address@hidden nbd_server_remove
+Stop exporting a block device through QEMU's NBD server, which was
+previously started with @command{nbd_server_add}.  The @option{-f}
+option forces the server to drop the export immediately even if
+clients are connected; otherwise the command fails unless there are no
+clients.
 ETEXI

     {
-- 
2.14.3