@@ -387,10 +387,12 @@ void hmp_nbd_server_start(Monitor *mon, const QDict *qdict)
bool writable = qdict_get_try_bool(qdict, "writable", false);
bool all = qdict_get_try_bool(qdict, "all", false);
Error *local_err = NULL;
- BlockInfoList *block_list, *info;
+ BlockBackend *blk;
SocketAddress *addr;
NbdServerAddOptions export;
+ GRAPH_RDLOCK_GUARD_MAINLOOP();
+
if (writable && !all) {
error_setg(&local_err, "-w only valid together with -a");
goto exit;
@@ -415,29 +417,43 @@ void hmp_nbd_server_start(Monitor *mon, const QDict *qdict)
/* Then try adding all block devices. If one fails, close all and
* exit.
*/
- block_list = qmp_query_block(NULL);
+ for (blk = blk_all_next(NULL); blk; blk = blk_all_next(blk)) {
+ BlockDriverState *bs = blk_bs(blk);
- for (info = block_list; info; info = info->next) {
- if (!info->value->inserted) {
+ if (!*blk_name(blk)) {
+ continue;
+ }
+
+ /*
+ * Note: historically we used to call qmp_query_block() to get
+ * the list of block devices. The two 'continue' cases below
+ * are the same as used by that function and are here to
+ * preserve behavior.
+ */
+
+ if (!blk_get_attached_dev(blk)) {
+ continue;
+ }
+
+ bs = bdrv_skip_implicit_filters(bs);
+ if (!bs || !bs->drv) {
continue;
}
export = (NbdServerAddOptions) {
- .device = info->value->device,
+ .device = g_strdup(blk_name(blk)),
.has_writable = true,
.writable = writable,
};
qmp_nbd_server_add(&export, &local_err);
-
+ g_free(export.device);
if (local_err != NULL) {
qmp_nbd_server_stop(NULL);
break;
}
}
- qapi_free_BlockInfoList(block_list);
-
exit:
hmp_handle_error(mon, local_err);
}
We're currently doing a full query-block just to enumerate the devices for qmp_nbd_server_add and then discarding the BlockInfoList afterwards. Alter hmp_nbd_server_start to instead iterate explicitly over the block_backends list. This allows the removal of the dependency on qmp_query_block from hmp_nbd_server_start. This is desirable because we're about to move qmp_query_block into a coroutine and don't need to change the NBD code at the same time. Add the GRAPH_RDLOCK_GUARD_MAINLOOP macro because bdrv_skip_implicit_filters() needs the graph lock. Signed-off-by: Fabiano Rosas <farosas@suse.de> --- - add a comment explaining some checks are done to preserve previous behavior; - we need the strdup when assigning .device to preserve const. Just add a matching g_free(); - about the possible leak at qmp_nbd_server_add() unrelated to this patch, commit 8675cbd68b ("nbd: Utilize QAPI_CLONE for type conversion") mentions that the QAPI visitor will already free arg->name. --- block/monitor/block-hmp-cmds.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-)