@@ -5574,3 +5574,65 @@
{ 'command': 'blockdev-snapshot-delete-internal-sync',
'data': { 'device': 'str', '*id': 'str', '*name': 'str'},
'returns': 'SnapshotInfo' }
+
+##
+# @BlockParentType:
+#
+# Since 7.0
+##
+{ 'enum': 'BlockParentType',
+ 'data': ['qdev', 'driver', 'export'] }
+
+##
+# @BdrvChildRefQdev:
+#
+# Since 7.0
+##
+{ 'struct': 'BdrvChildRefQdev',
+ 'data': { 'qdev-id': 'str' } }
+
+##
+# @BdrvChildRefExport:
+#
+# Since 7.0
+##
+{ 'struct': 'BdrvChildRefExport',
+ 'data': { 'export-id': 'str' } }
+
+##
+# @BdrvChildRefDriver:
+#
+# Since 7.0
+##
+{ 'struct': 'BdrvChildRefDriver',
+ 'data': { 'node-name': 'str', 'child': 'str' } }
+
+##
+# @BlockdevReplace:
+#
+# Since 7.0
+##
+{ 'union': 'BlockdevReplace',
+ 'base': {
+ 'parent-type': 'BlockParentType',
+ 'new-child': 'str'
+ },
+ 'discriminator': 'parent-type',
+ 'data': {
+ 'qdev': 'BdrvChildRefQdev',
+ 'export': 'BdrvChildRefExport',
+ 'driver': 'BdrvChildRefDriver'
+ } }
+
+##
+# @x-blockdev-replace:
+#
+# Replace a block-node associated with device (selected by
+# @qdev-id) or with block-export (selected by @export-id) or
+# any child of block-node (selected by @node-name and @child)
+# with @new-child block-node.
+#
+# Since 7.0
+##
+{ 'command': 'x-blockdev-replace', 'boxed': true,
+ 'data': 'BlockdevReplace' }
@@ -2229,6 +2229,71 @@ static void blockdev_add_abort(BlkActionState *common)
bdrv_unref(s->bs);
}
+static int blockdev_replace(BlockdevReplace *repl, Transaction *tran,
+ Error **errp)
+{
+ BdrvChild *child = NULL;
+ BlockDriverState *new_child_bs;
+
+ if (repl->parent_type == BLOCK_PARENT_TYPE_DRIVER) {
+ BlockDriverState *parent_bs;
+
+ parent_bs = bdrv_find_node(repl->u.driver.node_name);
+ if (!parent_bs) {
+ error_setg(errp, "Block driver node with node-name '%s' not "
+ "found", repl->u.driver.node_name);
+ return -EINVAL;
+ }
+
+ child = bdrv_find_child(parent_bs, repl->u.driver.child);
+ if (!child) {
+ error_setg(errp, "Block driver node '%s' doesn't have child "
+ "named '%s'", repl->u.driver.node_name,
+ repl->u.driver.child);
+ return -EINVAL;
+ }
+ } else {
+ /* Other types are similar, they work through blk */
+ BlockBackend *blk;
+ bool is_qdev = repl->parent_type == BLOCK_PARENT_TYPE_QDEV;
+ const char *id =
+ is_qdev ? repl->u.qdev.qdev_id : repl->u.export.export_id;
+
+ assert(is_qdev || repl->parent_type == BLOCK_PARENT_TYPE_EXPORT);
+
+ blk = is_qdev ? blk_by_qdev_id(id, errp) : blk_by_export_id(id, errp);
+ if (!blk) {
+ return -EINVAL;
+ }
+
+ child = blk_root(blk);
+ if (!child) {
+ error_setg(errp, "%s '%s' is empty, nothing to replace",
+ is_qdev ? "Device" : "Export", id);
+ return -EINVAL;
+ }
+ }
+
+ assert(child);
+ assert(child->bs);
+
+ new_child_bs = bdrv_find_node(repl->new_child);
+ if (!new_child_bs) {
+ error_setg(errp, "Node '%s' not found", repl->new_child);
+ return -EINVAL;
+ }
+
+ return bdrv_replace_child_bs(child, new_child_bs, tran, errp);
+}
+
+void qmp_x_blockdev_replace(BlockdevReplace *repl, Error **errp)
+{
+ Transaction *tran = tran_new();
+ int ret = blockdev_replace(repl, tran, errp);
+
+ tran_finalize(tran, ret);
+}
+
static const BlkActionOps actions[] = {
[TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT] = {
.instance_size = sizeof(ExternalSnapshotState),
new file mode 100644
@@ -0,0 +1,9 @@
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "sysemu/block-backend.h"
+
+BlockBackend *blk_by_qdev_id(const char *id, Error **errp)
+{
+ error_setg(errp, "blk '%s' not found", id);
+ return NULL;
+}
@@ -1,6 +1,7 @@
stub_ss.add(files('bdrv-next-monitor-owned.c'))
stub_ss.add(files('blk-commit-all.c'))
stub_ss.add(files('blk-exp-close-all.c'))
+stub_ss.add(files('blk-by-qdev-id.c'))
stub_ss.add(files('blockdev-close-all-bdrv-states.c'))
stub_ss.add(files('change-state-handler.c'))
stub_ss.add(files('cmos.c'))
Add a command that can replace bs in following BdrvChild structures: - qdev blk root child - block-export blk root child - any child BlockDriverState selected by child-name Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> --- qapi/block-core.json | 62 ++++++++++++++++++++++++++++++++++++++++ blockdev.c | 65 ++++++++++++++++++++++++++++++++++++++++++ stubs/blk-by-qdev-id.c | 9 ++++++ stubs/meson.build | 1 + 4 files changed, 137 insertions(+) create mode 100644 stubs/blk-by-qdev-id.c