storage-daemon/qemu-storage-daemon.c

   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 }