[Qemu-devel] [PATCH COLO-BLOCK v8 03/18] hmp: add monitor command to add/remove a child

[Wen Congyang]

Signed-off-by: Wen Congyang <we...@cn.fujitsu.com>
Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
Signed-off-by: Gonglei <arei.gong...@huawei.com>
---
 blockdev.c                | 53 +++++++++++++++++++++++++++++++++++++++++++++++
 hmp-commands.hx           | 28 +++++++++++++++++++++++++
 include/sysemu/blockdev.h |  2 ++
 3 files changed, 83 insertions(+)

diff --git a/blockdev.c b/blockdev.c
index c11611d..e5f7779 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2186,6 +2186,59 @@ void hmp_drive_del(Monitor *mon, const QDict *qdict)
     aio_context_release(aio_context);
 }
 
+void hmp_child_add(Monitor *mon, const QDict *qdict)
+{
+    const char *id = qdict_get_str(qdict, "id");
+    const char *optstr = qdict_get_str(qdict, "opts");
+    QemuOpts *opts;
+    QDict *bs_opts = qdict_new();
+    BlockDriverState *bs;
+    Error *local_err = NULL;
+
+    opts = drive_def(optstr);
+    if (!opts) {
+        /* We have reported error in drive_def */
+        return;
+    }
+    bs_opts = qemu_opts_to_qdict(opts, bs_opts);
+
+    bs = bdrv_lookup_bs(id, id, &local_err);
+    if (!bs) {
+        error_report_err(local_err);
+        return;
+    }
+
+    bdrv_add_child(bs, bs_opts, &local_err);
+    if (local_err) {
+        error_report_err(local_err);
+    }
+}
+
+void hmp_child_del(Monitor *mon, const QDict *qdict)
+{
+    const char *id = qdict_get_str(qdict, "id");
+    const char *child_id = qdict_get_str(qdict, "child");
+    BlockDriverState *bs, *child_bs;
+    Error *local_err = NULL;
+
+    bs = bdrv_lookup_bs(id, id, &local_err);
+    if (!bs) {
+        error_report_err(local_err);
+        return;
+    }
+
+    child_bs = bdrv_lookup_bs(child_id, child_id, &local_err);
+    if (!child_bs) {
+        error_report_err(local_err);
+        return;
+    }
+
+    bdrv_del_child(bs, child_bs, &local_err);
+    if (local_err) {
+        error_report_err(local_err);
+    }
+}
+
 void qmp_block_resize(bool has_device, const char *device,
                       bool has_node_name, const char *node_name,
                       int64_t size, Error **errp)
diff --git a/hmp-commands.hx b/hmp-commands.hx
index d3b7932..1d5b392 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -193,6 +193,34 @@ actions (drive options rerror, werror).
 ETEXI
 
     {
+        .name       = "child_add",
+        .args_type  = "id:B,opts:s",
+        .params     = "device child.file=file",
+        .help       = "add a child to a BDS",
+        .mhandler.cmd = hmp_child_add,
+    },
+
+STEXI
+@item child_add @var{device} @var{options}
+@findex child_add
+Add a child to the block device.
+ETEXI
+
+    {
+        .name       = "child_del",
+        .args_type  = "id:B,child:B",
+        .params     = "parent child",
+        .help       = "remove a child from a BDS",
+        .mhandler.cmd = hmp_child_del,
+    },
+
+STEXI
+@item child_del @var{parent device} @var{child device}
+@findex child_del
+Remove a child from the parent device.
+ETEXI
+
+    {
         .name       = "change",
         .args_type  = "device:B,target:F,arg:s?",
         .params     = "device filename [format]",
diff --git a/include/sysemu/blockdev.h b/include/sysemu/blockdev.h
index 3104150..594bfab 100644
--- a/include/sysemu/blockdev.h
+++ b/include/sysemu/blockdev.h
@@ -67,4 +67,6 @@ void qmp_change_blockdev(const char *device, const char 
*filename,
                          const char *format, Error **errp);
 void hmp_commit(Monitor *mon, const QDict *qdict);
 void hmp_drive_del(Monitor *mon, const QDict *qdict);
+void hmp_child_add(Monitor *mon, const QDict *qdict);
+void hmp_child_del(Monitor *mon, const QDict *qdict);
 #endif
-- 
2.4.3