1 /*
2  * QEMU storage daemon
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  * Copyright (c) 2019 Kevin Wolf <kwolf@redhat.com>
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 
28 #include <getopt.h>
29 
30 #include "block/block.h"
31 #include "block/nbd.h"
32 #include "chardev/char.h"
33 #include "crypto/init.h"
34 #include "monitor/monitor.h"
35 #include "monitor/monitor-internal.h"
36 
37 #include "qapi/error.h"
38 #include "qapi/qapi-visit-block-core.h"
39 #include "qapi/qapi-visit-block-export.h"
40 #include "qapi/qapi-visit-control.h"
41 #include "qapi/qmp/qdict.h"
42 #include "qapi/qmp/qstring.h"
43 #include "qapi/qobject-input-visitor.h"
44 
45 #include "qemu-common.h"
46 #include "qemu-version.h"
47 #include "qemu/config-file.h"
48 #include "qemu/error-report.h"
49 #include "qemu/help_option.h"
50 #include "qemu/log.h"
51 #include "qemu/main-loop.h"
52 #include "qemu/module.h"
53 #include "qemu/option.h"
54 #include "qom/object_interfaces.h"
55 
56 #include "storage-daemon/qapi/qapi-commands.h"
57 #include "storage-daemon/qapi/qapi-init-commands.h"
58 
59 #include "sysemu/runstate.h"
60 #include "trace/control.h"
61 
62 static const char *pid_file;
63 static volatile bool exit_requested = false;
64 
65 void qemu_system_killed(int signal, pid_t pid)
66 {
67     exit_requested = true;
68 }
69 
70 void qmp_quit(Error **errp)
71 {
72     exit_requested = true;
73 }
74 
75 static void help(void)
76 {
77     printf(
78 "Usage: %s [options]\n"
79 "QEMU storage daemon\n"
80 "\n"
81 "  -h, --help             display this help and exit\n"
82 "  -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
83 "                         specify tracing options\n"
84 "  -V, --version          output version information and exit\n"
85 "\n"
86 "  --blockdev [driver=]<driver>[,node-name=<N>][,discard=ignore|unmap]\n"
87 "             [,cache.direct=on|off][,cache.no-flush=on|off]\n"
88 "             [,read-only=on|off][,auto-read-only=on|off]\n"
89 "             [,force-share=on|off][,detect-zeroes=on|off|unmap]\n"
90 "             [,driver specific parameters...]\n"
91 "                         configure a block backend\n"
92 "\n"
93 "  --chardev <options>    configure a character device backend\n"
94 "                         (see the qemu(1) man page for possible options)\n"
95 "\n"
96 "  --daemonize            daemonize the process, and have the parent exit\n"
97 "                         once startup is complete\n"
98 "\n"
99 "  --export [type=]nbd,id=<id>,node-name=<node-name>[,name=<export-name>]\n"
100 "           [,writable=on|off][,bitmap=<name>]\n"
101 "                         export the specified block node over NBD\n"
102 "                         (requires --nbd-server)\n"
103 "\n"
104 #ifdef CONFIG_FUSE
105 "  --export [type=]fuse,id=<id>,node-name=<node-name>,mountpoint=<file>\n"
106 "           [,growable=on|off][,writable=on|off][,allow-other=on|off|auto]\n"
107 "                         export the specified block node over FUSE\n"
108 "\n"
109 #endif /* CONFIG_FUSE */
110 #ifdef CONFIG_VHOST_USER_BLK_SERVER
111 "  --export [type=]vhost-user-blk,id=<id>,node-name=<node-name>,\n"
112 "           addr.type=unix,addr.path=<socket-path>[,writable=on|off]\n"
113 "           [,logical-block-size=<block-size>][,num-queues=<num-queues>]\n"
114 "                         export the specified block node as a\n"
115 "                         vhost-user-blk device over UNIX domain socket\n"
116 "  --export [type=]vhost-user-blk,id=<id>,node-name=<node-name>,\n"
117 "           addr.type=fd,addr.str=<fd>[,writable=on|off]\n"
118 "           [,logical-block-size=<block-size>][,num-queues=<num-queues>]\n"
119 "                         export the specified block node as a\n"
120 "                         vhost-user-blk device over file descriptor\n"
121 "\n"
122 #endif /* CONFIG_VHOST_USER_BLK_SERVER */
123 "  --monitor [chardev=]name[,mode=control][,pretty[=on|off]]\n"
124 "                         configure a QMP monitor\n"
125 "\n"
126 "  --nbd-server addr.type=inet,addr.host=<host>,addr.port=<port>\n"
127 "               [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n"
128 "  --nbd-server addr.type=unix,addr.path=<path>\n"
129 "               [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n"
130 "                         start an NBD server for exporting block nodes\n"
131 "\n"
132 "  --object help          list object types that can be added\n"
133 "  --object <type>,help   list properties for the given object type\n"
134 "  --object <type>[,<property>=<value>...]\n"
135 "                         create a new object of type <type>, setting\n"
136 "                         properties in the order they are specified. Note\n"
137 "                         that the 'id' property must be set.\n"
138 "                         See the qemu(1) man page for documentation of the\n"
139 "                         objects that can be added.\n"
140 "\n"
141 "  --pidfile <path>       write process ID to a file after startup\n"
142 "\n"
143 QEMU_HELP_BOTTOM "\n",
144     g_get_prgname());
145 }
146 
147 enum {
148     OPTION_BLOCKDEV = 256,
149     OPTION_CHARDEV,
150     OPTION_DAEMONIZE,
151     OPTION_EXPORT,
152     OPTION_MONITOR,
153     OPTION_NBD_SERVER,
154     OPTION_OBJECT,
155     OPTION_PIDFILE,
156 };
157 
158 extern QemuOptsList qemu_chardev_opts;
159 
160 static void init_qmp_commands(void)
161 {
162     qmp_init_marshal(&qmp_commands);
163 
164     QTAILQ_INIT(&qmp_cap_negotiation_commands);
165     qmp_register_command(&qmp_cap_negotiation_commands, "qmp_capabilities",
166                          qmp_marshal_qmp_capabilities,
167                          QCO_ALLOW_PRECONFIG, 0);
168 }
169 
170 static int getopt_set_loc(int argc, char **argv, const char *optstring,
171                           const struct option *longopts)
172 {
173     int c, save_index;
174 
175     optarg = NULL;
176     save_index = optind;
177     c = getopt_long(argc, argv, optstring, longopts, NULL);
178     if (optarg) {
179         loc_set_cmdline(argv, save_index, MAX(1, optind - save_index));
180     }
181     return c;
182 }
183 
184 /**
185  * Process QSD command-line arguments.
186  *
187  * This is done in two passes:
188  *
189  * First (@pre_init_pass is true), we do a pass where all global
190  * arguments pertaining to the QSD process (like --help or --daemonize)
191  * are processed.  This pass is done before most of the QEMU-specific
192  * initialization steps (e.g. initializing the block layer or QMP), and
193  * so must only process arguments that are not really QEMU-specific.
194  *
195  * Second (@pre_init_pass is false), we (sequentially) process all
196  * QEMU/QSD-specific arguments.  Many of these arguments are effectively
197  * translated to QMP commands (like --blockdev for blockdev-add, or
198  * --export for block-export-add).
199  */
200 static void process_options(int argc, char *argv[], bool pre_init_pass)
201 {
202     int c;
203 
204     static const struct option long_options[] = {
205         {"blockdev", required_argument, NULL, OPTION_BLOCKDEV},
206         {"chardev", required_argument, NULL, OPTION_CHARDEV},
207         {"daemonize", no_argument, NULL, OPTION_DAEMONIZE},
208         {"export", required_argument, NULL, OPTION_EXPORT},
209         {"help", no_argument, NULL, 'h'},
210         {"monitor", required_argument, NULL, OPTION_MONITOR},
211         {"nbd-server", required_argument, NULL, OPTION_NBD_SERVER},
212         {"object", required_argument, NULL, OPTION_OBJECT},
213         {"pidfile", required_argument, NULL, OPTION_PIDFILE},
214         {"trace", required_argument, NULL, 'T'},
215         {"version", no_argument, NULL, 'V'},
216         {0, 0, 0, 0}
217     };
218 
219     /*
220      * In contrast to the system emulator, QEMU-specific options are processed
221      * in the order they are given on the command lines. This means that things
222      * must be defined first before they can be referenced in another option.
223      */
224     optind = 1;
225     while ((c = getopt_set_loc(argc, argv, "-hT:V", long_options)) != -1) {
226         bool handle_option_pre_init;
227 
228         /* Should this argument be processed in the pre-init pass? */
229         handle_option_pre_init =
230             c == '?' ||
231             c == 'h' ||
232             c == 'V' ||
233             c == OPTION_DAEMONIZE ||
234             c == OPTION_PIDFILE;
235 
236         /* Process every option only in its respective pass */
237         if (pre_init_pass != handle_option_pre_init) {
238             continue;
239         }
240 
241         switch (c) {
242         case '?':
243             exit(EXIT_FAILURE);
244         case 'h':
245             help();
246             exit(EXIT_SUCCESS);
247         case 'T':
248             trace_opt_parse(optarg);
249             trace_init_file();
250             break;
251         case 'V':
252             printf("qemu-storage-daemon version "
253                    QEMU_FULL_VERSION "\n" QEMU_COPYRIGHT "\n");
254             exit(EXIT_SUCCESS);
255         case OPTION_BLOCKDEV:
256             {
257                 Visitor *v;
258                 BlockdevOptions *options;
259 
260                 v = qobject_input_visitor_new_str(optarg, "driver",
261                                                   &error_fatal);
262 
263                 visit_type_BlockdevOptions(v, NULL, &options, &error_fatal);
264                 visit_free(v);
265 
266                 qmp_blockdev_add(options, &error_fatal);
267                 qapi_free_BlockdevOptions(options);
268                 break;
269             }
270         case OPTION_CHARDEV:
271             {
272                 /* TODO This interface is not stable until we QAPIfy it */
273                 QemuOpts *opts = qemu_opts_parse_noisily(&qemu_chardev_opts,
274                                                          optarg, true);
275                 if (opts == NULL) {
276                     exit(EXIT_FAILURE);
277                 }
278 
279                 if (!qemu_chr_new_from_opts(opts, NULL, &error_fatal)) {
280                     /* No error, but NULL returned means help was printed */
281                     exit(EXIT_SUCCESS);
282                 }
283                 qemu_opts_del(opts);
284                 break;
285             }
286         case OPTION_DAEMONIZE:
287             if (os_set_daemonize(true) < 0) {
288                 error_report("--daemonize not supported in this build");
289                 exit(EXIT_FAILURE);
290             }
291             break;
292         case OPTION_EXPORT:
293             {
294                 Visitor *v;
295                 BlockExportOptions *export;
296 
297                 v = qobject_input_visitor_new_str(optarg, "type", &error_fatal);
298                 visit_type_BlockExportOptions(v, NULL, &export, &error_fatal);
299                 visit_free(v);
300 
301                 qmp_block_export_add(export, &error_fatal);
302                 qapi_free_BlockExportOptions(export);
303                 break;
304             }
305         case OPTION_MONITOR:
306             {
307                 Visitor *v;
308                 MonitorOptions *monitor;
309 
310                 v = qobject_input_visitor_new_str(optarg, "chardev",
311                                                   &error_fatal);
312                 visit_type_MonitorOptions(v, NULL, &monitor, &error_fatal);
313                 visit_free(v);
314 
315                 /* TODO Catch duplicate monitor IDs */
316                 monitor_init(monitor, false, &error_fatal);
317                 qapi_free_MonitorOptions(monitor);
318                 break;
319             }
320         case OPTION_NBD_SERVER:
321             {
322                 Visitor *v;
323                 NbdServerOptions *options;
324 
325                 v = qobject_input_visitor_new_str(optarg, NULL, &error_fatal);
326                 visit_type_NbdServerOptions(v, NULL, &options, &error_fatal);
327                 visit_free(v);
328 
329                 nbd_server_start_options(options, &error_fatal);
330                 qapi_free_NbdServerOptions(options);
331                 break;
332             }
333         case OPTION_OBJECT:
334             user_creatable_process_cmdline(optarg);
335             break;
336         case OPTION_PIDFILE:
337             pid_file = optarg;
338             break;
339         case 1:
340             error_report("Unexpected argument");
341             exit(EXIT_FAILURE);
342         default:
343             g_assert_not_reached();
344         }
345     }
346     loc_set_none();
347 }
348 
349 static void pid_file_cleanup(void)
350 {
351     unlink(pid_file);
352 }
353 
354 static void pid_file_init(void)
355 {
356     Error *err = NULL;
357 
358     if (!pid_file) {
359         return;
360     }
361 
362     if (!qemu_write_pidfile(pid_file, &err)) {
363         error_reportf_err(err, "cannot create PID file: ");
364         exit(EXIT_FAILURE);
365     }
366 
367     atexit(pid_file_cleanup);
368 }
369 
370 int main(int argc, char *argv[])
371 {
372 #ifdef CONFIG_POSIX
373     signal(SIGPIPE, SIG_IGN);
374 #endif
375 
376     error_init(argv[0]);
377     qemu_init_exec_dir(argv[0]);
378     os_setup_signal_handling();
379 
380     process_options(argc, argv, true);
381 
382     os_daemonize();
383 
384     module_call_init(MODULE_INIT_QOM);
385     module_call_init(MODULE_INIT_TRACE);
386     qemu_add_opts(&qemu_trace_opts);
387     qcrypto_init(&error_fatal);
388     bdrv_init();
389     monitor_init_globals_core();
390     init_qmp_commands();
391 
392     if (!trace_init_backends()) {
393         return EXIT_FAILURE;
394     }
395     qemu_set_log(LOG_TRACE);
396 
397     qemu_init_main_loop(&error_fatal);
398     process_options(argc, argv, false);
399 
400     /*
401      * Write the pid file after creating chardevs, exports, and NBD servers but
402      * before accepting connections. This ordering is documented. Do not change
403      * it.
404      */
405     pid_file_init();
406     os_setup_post();
407 
408     while (!exit_requested) {
409         main_loop_wait(false);
410     }
411 
412     blk_exp_close_all();
413     bdrv_drain_all_begin();
414     job_cancel_sync_all();
415     bdrv_close_all();
416 
417     monitor_cleanup();
418     qemu_chr_cleanup();
419     user_creatable_cleanup();
420 
421     return EXIT_SUCCESS;
422 }
423