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