2 * Core Definitions for QAPI/QMP Dispatch
4 * Copyright IBM, Corp. 2011
7 * Anthony Liguori <aliguori@us.ibm.com>
9 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
10 * See the COPYING.LIB file in the top-level directory.
14 #include "qemu/osdep.h"
16 #include "block/aio.h"
17 #include "qapi/error.h"
18 #include "qapi/qmp/dispatch.h"
19 #include "qapi/qmp/qdict.h"
20 #include "qapi/qmp/qjson.h"
21 #include "sysemu/runstate.h"
22 #include "qapi/qmp/qbool.h"
23 #include "qemu/coroutine.h"
24 #include "qemu/main-loop.h"
26 static QDict *qmp_dispatch_check_obj(QDict *dict, bool allow_oob,
29 const char *exec_key = NULL;
30 const QDictEntry *ent;
32 const QObject *arg_obj;
34 for (ent = qdict_first(dict); ent;
35 ent = qdict_next(dict, ent)) {
36 arg_name = qdict_entry_key(ent);
37 arg_obj = qdict_entry_value(ent);
39 if (!strcmp(arg_name, "execute")
40 || (!strcmp(arg_name, "exec-oob") && allow_oob)) {
41 if (qobject_type(arg_obj) != QTYPE_QSTRING) {
42 error_setg(errp, "QMP input member '%s' must be a string",
47 error_setg(errp, "QMP input member '%s' clashes with '%s'",
52 } else if (!strcmp(arg_name, "arguments")) {
53 if (qobject_type(arg_obj) != QTYPE_QDICT) {
55 "QMP input member 'arguments' must be an object");
58 } else if (!strcmp(arg_name, "id")) {
61 error_setg(errp, "QMP input member '%s' is unexpected",
68 error_setg(errp, "QMP input lacks member 'execute'");
75 QDict *qmp_error_response(Error *err)
79 rsp = qdict_from_jsonf_nofail("{ 'error': { 'class': %s, 'desc': %s } }",
80 QapiErrorClass_str(error_get_class(err)),
81 error_get_pretty(err));
87 * Does @qdict look like a command to be run out-of-band?
89 bool qmp_is_oob(const QDict *dict)
91 return qdict_haskey(dict, "exec-oob")
92 && !qdict_haskey(dict, "execute");
95 typedef struct QmpDispatchBH {
96 const QmpCommand *cmd;
104 static void do_qmp_dispatch_bh(void *opaque)
106 QmpDispatchBH *data = opaque;
108 assert(monitor_cur() == NULL);
109 monitor_set_cur(qemu_coroutine_self(), data->cur_mon);
110 data->cmd->fn(data->args, data->ret, data->errp);
111 monitor_set_cur(qemu_coroutine_self(), NULL);
112 aio_co_wake(data->co);
116 * Runs outside of coroutine context for OOB commands, but in coroutine
117 * context for everything else.
119 QDict *qmp_dispatch(const QmpCommandList *cmds, QObject *request,
120 bool allow_oob, Monitor *cur_mon)
126 const QmpCommand *cmd;
132 dict = qobject_to(QDict, request);
135 error_setg(&err, "QMP input must be a JSON object");
139 id = qdict_get(dict, "id");
141 if (!qmp_dispatch_check_obj(dict, allow_oob, &err)) {
145 command = qdict_get_try_str(dict, "execute");
149 command = qdict_get_str(dict, "exec-oob");
152 cmd = qmp_find_command(cmds, command);
154 error_set(&err, ERROR_CLASS_COMMAND_NOT_FOUND,
155 "The command %s has not been found", command);
159 error_set(&err, ERROR_CLASS_COMMAND_NOT_FOUND,
160 "The command %s has been disabled for this instance",
164 if (oob && !(cmd->options & QCO_ALLOW_OOB)) {
165 error_setg(&err, "The command %s does not support OOB",
170 if (!qmp_command_available(cmd, &err)) {
174 if (!qdict_haskey(dict, "arguments")) {
177 args = qdict_get_qdict(dict, "arguments");
181 assert(!(oob && qemu_in_coroutine()));
182 assert(monitor_cur() == NULL);
183 if (!!(cmd->options & QCO_COROUTINE) == qemu_in_coroutine()) {
184 monitor_set_cur(qemu_coroutine_self(), cur_mon);
185 cmd->fn(args, &ret, &err);
186 monitor_set_cur(qemu_coroutine_self(), NULL);
189 * Actual context doesn't match the one the command needs.
191 * Case 1: we are in coroutine context, but command does not
192 * have QCO_COROUTINE. We need to drop out of coroutine
193 * context for executing it.
195 * Case 2: we are outside coroutine context, but command has
196 * QCO_COROUTINE. Can't actually happen, because we get here
197 * outside coroutine context only when executing a command
198 * out of band, and OOB commands never have QCO_COROUTINE.
200 assert(!oob && qemu_in_coroutine() && !(cmd->options & QCO_COROUTINE));
202 QmpDispatchBH data = {
208 .co = qemu_coroutine_self(),
210 aio_bh_schedule_oneshot(qemu_get_aio_context(), do_qmp_dispatch_bh,
212 qemu_coroutine_yield();
216 /* or assert(!ret) after reviewing all handlers: */
221 if (cmd->options & QCO_NO_SUCCESS_RESP) {
226 * When the command's schema has no 'returns', cmd->fn()
227 * leaves @ret null. The QMP spec calls for an empty object
230 ret = QOBJECT(qdict_new());
234 qdict_put_obj(rsp, "return", ret);
239 rsp = qmp_error_response(err);
245 qdict_put_obj(rsp, "id", qobject_ref(id));