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/help-texts.h"
46 #include "qemu-version.h"
47 #include "qemu/cutils.h"
48 #include "qemu/config-file.h"
49 #include "qemu/error-report.h"
50 #include "qemu/help_option.h"
51 #include "qemu/log.h"
52 #include "qemu/main-loop.h"
53 #include "qemu/module.h"
54 #include "qemu/option.h"
55 #include "qom/object_interfaces.h"
56 
57 #include "storage-daemon/qapi/qapi-commands.h"
58 #include "storage-daemon/qapi/qapi-init-commands.h"
59 
60 #include "sysemu/runstate.h"
61 #include "trace/control.h"
62 
63 static const char *pid_file;
64 static char *pid_file_realpath;
65 static volatile bool exit_requested = false;
66 
67 void qemu_system_killed(int signal, pid_t pid)
68 {
69     exit_requested = true;
70 }
71 
72 void qmp_quit(Error **errp)
73 {
74     exit_requested = true;
75 }
76 
77 static void help(void)
78 {
79     printf(
80 "Usage: %s [options]\n"
81 "QEMU storage daemon\n"
82 "\n"
83 "  -h, --help             display this help and exit\n"
84 "  -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
85 "                         specify tracing options\n"
86 "  -V, --version          output version information and exit\n"
87 "\n"
88 "  --blockdev [driver=]<driver>[,node-name=<N>][,discard=ignore|unmap]\n"
89 "             [,cache.direct=on|off][,cache.no-flush=on|off]\n"
90 "             [,read-only=on|off][,auto-read-only=on|off]\n"
91 "             [,force-share=on|off][,detect-zeroes=on|off|unmap]\n"
92 "             [,driver specific parameters...]\n"
93 "                         configure a block backend\n"
94 "\n"
95 "  --chardev <options>    configure a character device backend\n"
96 "                         (see the qemu(1) man page for possible options)\n"
97 "\n"
98 "  --daemonize            daemonize the process, and have the parent exit\n"
99 "                         once startup is complete\n"
100 "\n"
101 "  --export [type=]nbd,id=<id>,node-name=<node-name>[,name=<export-name>]\n"
102 "           [,writable=on|off][,bitmap=<name>]\n"
103 "                         export the specified block node over NBD\n"
104 "                         (requires --nbd-server)\n"
105 "\n"
106 #ifdef CONFIG_FUSE
107 "  --export [type=]fuse,id=<id>,node-name=<node-name>,mountpoint=<file>\n"
108 "           [,growable=on|off][,writable=on|off][,allow-other=on|off|auto]\n"
109 "                         export the specified block node over FUSE\n"
110 "\n"
111 #endif /* CONFIG_FUSE */
112 #ifdef CONFIG_VHOST_USER_BLK_SERVER
113 "  --export [type=]vhost-user-blk,id=<id>,node-name=<node-name>,\n"
114 "           addr.type=unix,addr.path=<socket-path>[,writable=on|off]\n"
115 "           [,logical-block-size=<block-size>][,num-queues=<num-queues>]\n"
116 "                         export the specified block node as a\n"
117 "                         vhost-user-blk device over UNIX domain socket\n"
118 "  --export [type=]vhost-user-blk,id=<id>,node-name=<node-name>,\n"
119 "           addr.type=fd,addr.str=<fd>[,writable=on|off]\n"
120 "           [,logical-block-size=<block-size>][,num-queues=<num-queues>]\n"
121 "                         export the specified block node as a\n"
122 "                         vhost-user-blk device over file descriptor\n"
123 "\n"
124 #endif /* CONFIG_VHOST_USER_BLK_SERVER */
125 #ifdef CONFIG_VDUSE_BLK_EXPORT
126 "  --export [type=]vduse-blk,id=<id>,node-name=<node-name>\n"
127 "           ,name=<vduse-name>[,writable=on|off]\n"
128 "           [,num-queues=<num-queues>][,queue-size=<queue-size>]\n"
129 "           [,logical-block-size=<logical-block-size>]\n"
130 "           [,serial=<serial-number>]\n"
131 "                         export the specified block node as a\n"
132 "                         vduse-blk device\n"
133 "\n"
134 #endif /* CONFIG_VDUSE_BLK_EXPORT */
135 "  --monitor [chardev=]name[,mode=control][,pretty[=on|off]]\n"
136 "                         configure a QMP monitor\n"
137 "\n"
138 "  --nbd-server addr.type=inet,addr.host=<host>,addr.port=<port>\n"
139 "               [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n"
140 "  --nbd-server addr.type=unix,addr.path=<path>\n"
141 "               [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n"
142 "                         start an NBD server for exporting block nodes\n"
143 "\n"
144 "  --object help          list object types that can be added\n"
145 "  --object <type>,help   list properties for the given object type\n"
146 "  --object <type>[,<property>=<value>...]\n"
147 "                         create a new object of type <type>, setting\n"
148 "                         properties in the order they are specified. Note\n"
149 "                         that the 'id' property must be set.\n"
150 "                         See the qemu(1) man page for documentation of the\n"
151 "                         objects that can be added.\n"
152 "\n"
153 "  --pidfile <path>       write process ID to a file after startup\n"
154 "\n"
155 QEMU_HELP_BOTTOM "\n",
156     g_get_prgname());
157 }
158 
159 enum {
160     OPTION_BLOCKDEV = 256,
161     OPTION_CHARDEV,
162     OPTION_DAEMONIZE,
163     OPTION_EXPORT,
164     OPTION_MONITOR,
165     OPTION_NBD_SERVER,
166     OPTION_OBJECT,
167     OPTION_PIDFILE,
168 };
169 
170 extern QemuOptsList qemu_chardev_opts;
171 
172 static void init_qmp_commands(void)
173 {
174     qmp_init_marshal(&qmp_commands);
175 
176     QTAILQ_INIT(&qmp_cap_negotiation_commands);
177     qmp_register_command(&qmp_cap_negotiation_commands, "qmp_capabilities",
178                          qmp_marshal_qmp_capabilities,
179                          QCO_ALLOW_PRECONFIG, 0);
180 }
181 
182 static int getopt_set_loc(int argc, char **argv, const char *optstring,
183                           const struct option *longopts)
184 {
185     int c, save_index;
186 
187     optarg = NULL;
188     save_index = optind;
189     c = getopt_long(argc, argv, optstring, longopts, NULL);
190     if (optarg) {
191         loc_set_cmdline(argv, save_index, MAX(1, optind - save_index));
192     }
193     return c;
194 }
195 
196 /**
197  * Process QSD command-line arguments.
198  *
199  * This is done in two passes:
200  *
201  * First (@pre_init_pass is true), we do a pass where all global
202  * arguments pertaining to the QSD process (like --help or --daemonize)
203  * are processed.  This pass is done before most of the QEMU-specific
204  * initialization steps (e.g. initializing the block layer or QMP), and
205  * so must only process arguments that are not really QEMU-specific.
206  *
207  * Second (@pre_init_pass is false), we (sequentially) process all
208  * QEMU/QSD-specific arguments.  Many of these arguments are effectively
209  * translated to QMP commands (like --blockdev for blockdev-add, or
210  * --export for block-export-add).
211  */
212 static void process_options(int argc, char *argv[], bool pre_init_pass)
213 {
214     int c;
215 
216     static const struct option long_options[] = {
217         {"blockdev", required_argument, NULL, OPTION_BLOCKDEV},
218         {"chardev", required_argument, NULL, OPTION_CHARDEV},
219         {"daemonize", no_argument, NULL, OPTION_DAEMONIZE},
220         {"export", required_argument, NULL, OPTION_EXPORT},
221         {"help", no_argument, NULL, 'h'},
222         {"monitor", required_argument, NULL, OPTION_MONITOR},
223         {"nbd-server", required_argument, NULL, OPTION_NBD_SERVER},
224         {"object", required_argument, NULL, OPTION_OBJECT},
225         {"pidfile", required_argument, NULL, OPTION_PIDFILE},
226         {"trace", required_argument, NULL, 'T'},
227         {"version", no_argument, NULL, 'V'},
228         {0, 0, 0, 0}
229     };
230 
231     /*
232      * In contrast to the system emulator, QEMU-specific options are processed
233      * in the order they are given on the command lines. This means that things
234      * must be defined first before they can be referenced in another option.
235      */
236     optind = 1;
237     while ((c = getopt_set_loc(argc, argv, "-hT:V", long_options)) != -1) {
238         bool handle_option_pre_init;
239 
240         /* Should this argument be processed in the pre-init pass? */
241         handle_option_pre_init =
242             c == '?' ||
243             c == 'h' ||
244             c == 'V' ||
245             c == OPTION_DAEMONIZE ||
246             c == OPTION_PIDFILE;
247 
248         /* Process every option only in its respective pass */
249         if (pre_init_pass != handle_option_pre_init) {
250             continue;
251         }
252 
253         switch (c) {
254         case '?':
255             exit(EXIT_FAILURE);
256         case 'h':
257             help();
258             exit(EXIT_SUCCESS);
259         case 'T':
260             trace_opt_parse(optarg);
261             trace_init_file();
262             break;
263         case 'V':
264             printf("qemu-storage-daemon version "
265                    QEMU_FULL_VERSION "\n" QEMU_COPYRIGHT "\n");
266             exit(EXIT_SUCCESS);
267         case OPTION_BLOCKDEV:
268             {
269                 Visitor *v;
270                 BlockdevOptions *options;
271 
272                 v = qobject_input_visitor_new_str(optarg, "driver",
273                                                   &error_fatal);
274 
275                 visit_type_BlockdevOptions(v, NULL, &options, &error_fatal);
276                 visit_free(v);
277 
278                 qmp_blockdev_add(options, &error_fatal);
279                 qapi_free_BlockdevOptions(options);
280                 break;
281             }
282         case OPTION_CHARDEV:
283             {
284                 /* TODO This interface is not stable until we QAPIfy it */
285                 QemuOpts *opts = qemu_opts_parse_noisily(&qemu_chardev_opts,
286                                                          optarg, true);
287                 if (opts == NULL) {
288                     exit(EXIT_FAILURE);
289                 }
290 
291                 if (!qemu_chr_new_from_opts(opts, NULL, &error_fatal)) {
292                     /* No error, but NULL returned means help was printed */
293                     exit(EXIT_SUCCESS);
294                 }
295                 qemu_opts_del(opts);
296                 break;
297             }
298         case OPTION_DAEMONIZE:
299             if (os_set_daemonize(true) < 0) {
300                 /*
301                  * --daemonize is parsed before monitor_init_globals_core(), so
302                  * error_report() does not work yet
303                  */
304                 fprintf(stderr, "--daemonize not supported in this build\n");
305                 exit(EXIT_FAILURE);
306             }
307             break;
308         case OPTION_EXPORT:
309             {
310                 Visitor *v;
311                 BlockExportOptions *export;
312 
313                 v = qobject_input_visitor_new_str(optarg, "type", &error_fatal);
314                 visit_type_BlockExportOptions(v, NULL, &export, &error_fatal);
315                 visit_free(v);
316 
317                 qmp_block_export_add(export, &error_fatal);
318                 qapi_free_BlockExportOptions(export);
319                 break;
320             }
321         case OPTION_MONITOR:
322             {
323                 Visitor *v;
324                 MonitorOptions *monitor;
325 
326                 v = qobject_input_visitor_new_str(optarg, "chardev",
327                                                   &error_fatal);
328                 visit_type_MonitorOptions(v, NULL, &monitor, &error_fatal);
329                 visit_free(v);
330 
331                 /* TODO Catch duplicate monitor IDs */
332                 monitor_init(monitor, false, &error_fatal);
333                 qapi_free_MonitorOptions(monitor);
334                 break;
335             }
336         case OPTION_NBD_SERVER:
337             {
338                 Visitor *v;
339                 NbdServerOptions *options;
340 
341                 v = qobject_input_visitor_new_str(optarg, NULL, &error_fatal);
342                 visit_type_NbdServerOptions(v, NULL, &options, &error_fatal);
343                 visit_free(v);
344 
345                 nbd_server_start_options(options, &error_fatal);
346                 qapi_free_NbdServerOptions(options);
347                 break;
348             }
349         case OPTION_OBJECT:
350             user_creatable_process_cmdline(optarg);
351             break;
352         case OPTION_PIDFILE:
353             pid_file = optarg;
354             break;
355         case 1:
356             error_report("Unexpected argument");
357             exit(EXIT_FAILURE);
358         default:
359             g_assert_not_reached();
360         }
361     }
362     loc_set_none();
363 }
364 
365 static void pid_file_cleanup(void)
366 {
367     unlink(pid_file_realpath);
368 }
369 
370 static void pid_file_init(void)
371 {
372     Error *err = NULL;
373 
374     if (!pid_file) {
375         return;
376     }
377 
378     if (!qemu_write_pidfile(pid_file, &err)) {
379         error_reportf_err(err, "cannot create PID file: ");
380         exit(EXIT_FAILURE);
381     }
382 
383     pid_file_realpath = g_malloc(PATH_MAX);
384     if (!realpath(pid_file, pid_file_realpath)) {
385         error_report("cannot resolve PID file path: %s: %s",
386                      pid_file, strerror(errno));
387         unlink(pid_file);
388         exit(EXIT_FAILURE);
389     }
390 
391     atexit(pid_file_cleanup);
392 }
393 
394 int main(int argc, char *argv[])
395 {
396 #ifdef CONFIG_POSIX
397     signal(SIGPIPE, SIG_IGN);
398 #endif
399 
400     error_init(argv[0]);
401     qemu_init_exec_dir(argv[0]);
402     os_setup_signal_handling();
403 
404     process_options(argc, argv, true);
405 
406     os_daemonize();
407 
408     module_call_init(MODULE_INIT_QOM);
409     module_call_init(MODULE_INIT_TRACE);
410     qemu_add_opts(&qemu_trace_opts);
411     qcrypto_init(&error_fatal);
412     bdrv_init();
413     monitor_init_globals_core();
414     init_qmp_commands();
415 
416     if (!trace_init_backends()) {
417         return EXIT_FAILURE;
418     }
419     qemu_set_log(LOG_TRACE, &error_fatal);
420 
421     qemu_init_main_loop(&error_fatal);
422     process_options(argc, argv, false);
423 
424     /*
425      * Write the pid file after creating chardevs, exports, and NBD servers but
426      * before accepting connections. This ordering is documented. Do not change
427      * it.
428      */
429     pid_file_init();
430     os_setup_post();
431 
432     while (!exit_requested) {
433         main_loop_wait(false);
434     }
435 
436     blk_exp_close_all();
437     bdrv_drain_all_begin();
438     job_cancel_sync_all();
439     bdrv_close_all();
440 
441     monitor_cleanup();
442     qemu_chr_cleanup();
443     user_creatable_cleanup();
444 
445     return EXIT_SUCCESS;
446 }
447