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