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