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 "  --export [type=]nbd,id=<id>,node-name=<node-name>[,name=<export-name>]\n"
  97 "           [,writable=on|off][,bitmap=<name>]\n"
  98 "                         export the specified block node over NBD\n"
  99 "                         (requires --nbd-server)\n"
 100 "\n"
 101 #ifdef CONFIG_FUSE
 102 "  --export [type=]fuse,id=<id>,node-name=<node-name>,mountpoint=<file>\n"
 103 "           [,growable=on|off][,writable=on|off]\n"
 104 "                         export the specified block node over FUSE\n"
 105 "\n"
 106 #endif /* CONFIG_FUSE */
 107 "  --monitor [chardev=]name[,mode=control][,pretty[=on|off]]\n"
 108 "                         configure a QMP monitor\n"
 109 "\n"
 110 "  --nbd-server addr.type=inet,addr.host=<host>,addr.port=<port>\n"
 111 "               [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n"
 112 "  --nbd-server addr.type=unix,addr.path=<path>\n"
 113 "               [,tls-creds=<id>][,tls-authz=<id>][,max-connections=<n>]\n"
 114 "                         start an NBD server for exporting block nodes\n"
 115 "\n"
 116 "  --object help          list object types that can be added\n"
 117 "  --object <type>,help   list properties for the given object type\n"
 118 "  --object <type>[,<property>=<value>...]\n"
 119 "                         create a new object of type <type>, setting\n"
 120 "                         properties in the order they are specified. Note\n"
 121 "                         that the 'id' property must be set.\n"
 122 "                         See the qemu(1) man page for documentation of the\n"
 123 "                         objects that can be added.\n"
 124 "\n"
 125 "  --pidfile <path>       write process ID to a file after startup\n"
 126 "\n"
 127 QEMU_HELP_BOTTOM "\n",
 128     error_get_progname());
 129 }
 130
 131 enum {
 132     OPTION_BLOCKDEV = 256,
 133     OPTION_CHARDEV,
 134     OPTION_EXPORT,
 135     OPTION_MONITOR,
 136     OPTION_NBD_SERVER,
 137     OPTION_OBJECT,
 138     OPTION_PIDFILE,
 139 };
 140
 141 extern QemuOptsList qemu_chardev_opts;
 142
 143 static void init_qmp_commands(void)
 144 {
 145     qmp_init_marshal(&qmp_commands);
 146
 147     QTAILQ_INIT(&qmp_cap_negotiation_commands);
 148     qmp_register_command(&qmp_cap_negotiation_commands, "qmp_capabilities",
 149                          qmp_marshal_qmp_capabilities,
 150                          QCO_ALLOW_PRECONFIG, 0);
 151 }
 152
 153 static int getopt_set_loc(int argc, char **argv, const char *optstring,
 154                           const struct option *longopts)
 155 {
 156     int c, save_index;
 157
 158     optarg = NULL;
 159     save_index = optind;
 160     c = getopt_long(argc, argv, optstring, longopts, NULL);
 161     if (optarg) {
 162         loc_set_cmdline(argv, save_index, MAX(1, optind - save_index));
 163     }
 164     return c;
 165 }
 166
 167 static void process_options(int argc, char *argv[])
 168 {
 169     int c;
 170
 171     static const struct option long_options[] = {
 172         {"blockdev", required_argument, NULL, OPTION_BLOCKDEV},
 173         {"chardev", required_argument, NULL, OPTION_CHARDEV},
 174         {"export", required_argument, NULL, OPTION_EXPORT},
 175         {"help", no_argument, NULL, 'h'},
 176         {"monitor", required_argument, NULL, OPTION_MONITOR},
 177         {"nbd-server", required_argument, NULL, OPTION_NBD_SERVER},
 178         {"object", required_argument, NULL, OPTION_OBJECT},
 179         {"pidfile", required_argument, NULL, OPTION_PIDFILE},
 180         {"trace", required_argument, NULL, 'T'},
 181         {"version", no_argument, NULL, 'V'},
 182         {0, 0, 0, 0}
 183     };
 184
 185     /*
 186      * In contrast to the system emulator, options are processed in the order
 187      * they are given on the command lines. This means that things must be
 188      * defined first before they can be referenced in another option.
 189      */
 190     while ((c = getopt_set_loc(argc, argv, "-hT:V", long_options)) != -1) {
 191         switch (c) {
 192         case '?':
 193             exit(EXIT_FAILURE);
 194         case 'h':
 195             help();
 196             exit(EXIT_SUCCESS);
 197         case 'T':
 198             trace_opt_parse(optarg);
 199             trace_init_file();
 200             break;
 201         case 'V':
 202             printf("qemu-storage-daemon version "
 203                    QEMU_FULL_VERSION "\n" QEMU_COPYRIGHT "\n");
 204             exit(EXIT_SUCCESS);
 205         case OPTION_BLOCKDEV:
 206             {
 207                 Visitor *v;
 208                 BlockdevOptions *options;
 209
 210                 v = qobject_input_visitor_new_str(optarg, "driver",
 211                                                   &error_fatal);
 212
 213                 visit_type_BlockdevOptions(v, NULL, &options, &error_fatal);
 214                 visit_free(v);
 215
 216                 qmp_blockdev_add(options, &error_fatal);
 217                 qapi_free_BlockdevOptions(options);
 218                 break;
 219             }
 220         case OPTION_CHARDEV:
 221             {
 222                 /* TODO This interface is not stable until we QAPIfy it */
 223                 QemuOpts *opts = qemu_opts_parse_noisily(&qemu_chardev_opts,
 224                                                          optarg, true);
 225                 if (opts == NULL) {
 226                     exit(EXIT_FAILURE);
 227                 }
 228
 229                 if (!qemu_chr_new_from_opts(opts, NULL, &error_fatal)) {
 230                     /* No error, but NULL returned means help was printed */
 231                     exit(EXIT_SUCCESS);
 232                 }
 233                 qemu_opts_del(opts);
 234                 break;
 235             }
 236         case OPTION_EXPORT:
 237             {
 238                 Visitor *v;
 239                 BlockExportOptions *export;
 240
 241                 v = qobject_input_visitor_new_str(optarg, "type", &error_fatal);
 242                 visit_type_BlockExportOptions(v, NULL, &export, &error_fatal);
 243                 visit_free(v);
 244
 245                 qmp_block_export_add(export, &error_fatal);
 246                 qapi_free_BlockExportOptions(export);
 247                 break;
 248             }
 249         case OPTION_MONITOR:
 250             {
 251                 Visitor *v;
 252                 MonitorOptions *monitor;
 253
 254                 v = qobject_input_visitor_new_str(optarg, "chardev",
 255                                                   &error_fatal);
 256                 visit_type_MonitorOptions(v, NULL, &monitor, &error_fatal);
 257                 visit_free(v);
 258
 259                 /* TODO Catch duplicate monitor IDs */
 260                 monitor_init(monitor, false, &error_fatal);
 261                 qapi_free_MonitorOptions(monitor);
 262                 break;
 263             }
 264         case OPTION_NBD_SERVER:
 265             {
 266                 Visitor *v;
 267                 NbdServerOptions *options;
 268
 269                 v = qobject_input_visitor_new_str(optarg, NULL, &error_fatal);
 270                 visit_type_NbdServerOptions(v, NULL, &options, &error_fatal);
 271                 visit_free(v);
 272
 273                 nbd_server_start_options(options, &error_fatal);
 274                 qapi_free_NbdServerOptions(options);
 275                 break;
 276             }
 277         case OPTION_OBJECT:
 278             user_creatable_process_cmdline(optarg);
 279             break;
 280         case OPTION_PIDFILE:
 281             pid_file = optarg;
 282             break;
 283         case 1:
 284             error_report("Unexpected argument");
 285             exit(EXIT_FAILURE);
 286         default:
 287             g_assert_not_reached();
 288         }
 289     }
 290     loc_set_none();
 291 }
 292
 293 static void pid_file_cleanup(void)
 294 {
 295     unlink(pid_file);
 296 }
 297
 298 static void pid_file_init(void)
 299 {
 300     Error *err = NULL;
 301
 302     if (!pid_file) {
 303         return;
 304     }
 305
 306     if (!qemu_write_pidfile(pid_file, &err)) {
 307         error_reportf_err(err, "cannot create PID file: ");
 308         exit(EXIT_FAILURE);
 309     }
 310
 311     atexit(pid_file_cleanup);
 312 }
 313
 314 int main(int argc, char *argv[])
 315 {
 316 #ifdef CONFIG_POSIX
 317     signal(SIGPIPE, SIG_IGN);
 318 #endif
 319
 320     error_init(argv[0]);
 321     qemu_init_exec_dir(argv[0]);
 322     os_setup_signal_handling();
 323
 324     module_call_init(MODULE_INIT_QOM);
 325     module_call_init(MODULE_INIT_TRACE);
 326     qemu_add_opts(&qemu_trace_opts);
 327     qcrypto_init(&error_fatal);
 328     bdrv_init();
 329     monitor_init_globals_core();
 330     init_qmp_commands();
 331
 332     if (!trace_init_backends()) {
 333         return EXIT_FAILURE;
 334     }
 335     qemu_set_log(LOG_TRACE);
 336
 337     qemu_init_main_loop(&error_fatal);
 338     process_options(argc, argv);
 339
 340     /*
 341      * Write the pid file after creating chardevs, exports, and NBD servers but
 342      * before accepting connections. This ordering is documented. Do not change
 343      * it.
 344      */
 345     pid_file_init();
 346
 347     while (!exit_requested) {
 348         main_loop_wait(false);
 349     }
 350
 351     blk_exp_close_all();
 352     bdrv_drain_all_begin();
 353     job_cancel_sync_all();
 354     bdrv_close_all();
 355
 356     monitor_cleanup();
 357     qemu_chr_cleanup();
 358     user_creatable_cleanup();
 359
 360     return EXIT_SUCCESS;
 361 }