block/qapi-sysemu.c

   1 /*
   2  * QMP command handlers specific to the system emulators
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or
   7  * later.  See the COPYING file in the top-level directory.
   8  *
   9  * This file incorporates work covered by the following copyright and
  10  * permission notice:
  11  *
  12  * Copyright (c) 2003-2008 Fabrice Bellard
  13  *
  14  * Permission is hereby granted, free of charge, to any person obtaining a copy
  15  * of this software and associated documentation files (the "Software"), to deal
  16  * in the Software without restriction, including without limitation the rights
  17  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  18  * copies of the Software, and to permit persons to whom the Software is
  19  * furnished to do so, subject to the following conditions:
  20  *
  21  * The above copyright notice and this permission notice shall be included in
  22  * all copies or substantial portions of the Software.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  25  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  26  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  27  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  28  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  29  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  30  * THE SOFTWARE.
  31  */
  32
  33 #include "qemu/osdep.h"
  34
  35 #include "block/block_int.h"
  36 #include "qapi/error.h"
  37 #include "qapi/qapi-commands-block.h"
  38 #include "qapi/qmp/qdict.h"
  39 #include "sysemu/block-backend.h"
  40 #include "sysemu/blockdev.h"
  41
  42 static BlockBackend *qmp_get_blk(const char *blk_name, const char *qdev_id,
  43                                  Error **errp)
  44 {
  45     BlockBackend *blk;
  46
  47     if (!blk_name == !qdev_id) {
  48         error_setg(errp, "Need exactly one of 'device' and 'id'");
  49         return NULL;
  50     }
  51
  52     if (qdev_id) {
  53         blk = blk_by_qdev_id(qdev_id, errp);
  54     } else {
  55         blk = blk_by_name(blk_name);
  56         if (blk == NULL) {
  57             error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
  58                       "Device '%s' not found", blk_name);
  59         }
  60     }
  61
  62     return blk;
  63 }
  64
  65 /*
  66  * Attempt to open the tray of @device.
  67  * If @force, ignore its tray lock.
  68  * Else, if the tray is locked, don't open it, but ask the guest to open it.
  69  * On error, store an error through @errp and return -errno.
  70  * If @device does not exist, return -ENODEV.
  71  * If it has no removable media, return -ENOTSUP.
  72  * If it has no tray, return -ENOSYS.
  73  * If the guest was asked to open the tray, return -EINPROGRESS.
  74  * Else, return 0.
  75  */
  76 static int do_open_tray(const char *blk_name, const char *qdev_id,
  77                         bool force, Error **errp)
  78 {
  79     BlockBackend *blk;
  80     const char *device = qdev_id ?: blk_name;
  81     bool locked;
  82
  83     blk = qmp_get_blk(blk_name, qdev_id, errp);
  84     if (!blk) {
  85         return -ENODEV;
  86     }
  87
  88     if (!blk_dev_has_removable_media(blk)) {
  89         error_setg(errp, "Device '%s' is not removable", device);
  90         return -ENOTSUP;
  91     }
  92
  93     if (!blk_dev_has_tray(blk)) {
  94         error_setg(errp, "Device '%s' does not have a tray", device);
  95         return -ENOSYS;
  96     }
  97
  98     if (blk_dev_is_tray_open(blk)) {
  99         return 0;
 100     }
 101
 102     locked = blk_dev_is_medium_locked(blk);
 103     if (locked) {
 104         blk_dev_eject_request(blk, force);
 105     }
 106
 107     if (!locked || force) {
 108         blk_dev_change_media_cb(blk, false, &error_abort);
 109     }
 110
 111     if (locked && !force) {
 112         error_setg(errp, "Device '%s' is locked and force was not specified, "
 113                    "wait for tray to open and try again", device);
 114         return -EINPROGRESS;
 115     }
 116
 117     return 0;
 118 }
 119
 120 void qmp_blockdev_open_tray(const char *device,
 121                             const char *id,
 122                             bool has_force, bool force,
 123                             Error **errp)
 124 {
 125     Error *local_err = NULL;
 126     int rc;
 127
 128     if (!has_force) {
 129         force = false;
 130     }
 131     rc = do_open_tray(device, id, force, &local_err);
 132     if (rc && rc != -ENOSYS && rc != -EINPROGRESS) {
 133         error_propagate(errp, local_err);
 134         return;
 135     }
 136     error_free(local_err);
 137 }
 138
 139 void qmp_blockdev_close_tray(const char *device,
 140                              const char *id,
 141                              Error **errp)
 142 {
 143     BlockBackend *blk;
 144     Error *local_err = NULL;
 145
 146     blk = qmp_get_blk(device, id, errp);
 147     if (!blk) {
 148         return;
 149     }
 150
 151     if (!blk_dev_has_removable_media(blk)) {
 152         error_setg(errp, "Device '%s' is not removable", device ?: id);
 153         return;
 154     }
 155
 156     if (!blk_dev_has_tray(blk)) {
 157         /* Ignore this command on tray-less devices */
 158         return;
 159     }
 160
 161     if (!blk_dev_is_tray_open(blk)) {
 162         return;
 163     }
 164
 165     blk_dev_change_media_cb(blk, true, &local_err);
 166     if (local_err) {
 167         error_propagate(errp, local_err);
 168         return;
 169     }
 170 }
 171
 172 static void GRAPH_UNLOCKED
 173 blockdev_remove_medium(const char *device, const char *id, Error **errp)
 174 {
 175     BlockBackend *blk;
 176     BlockDriverState *bs;
 177     AioContext *aio_context;
 178     bool has_attached_device;
 179
 180     GLOBAL_STATE_CODE();
 181
 182     blk = qmp_get_blk(device, id, errp);
 183     if (!blk) {
 184         return;
 185     }
 186
 187     /* For BBs without a device, we can exchange the BDS tree at will */
 188     has_attached_device = blk_get_attached_dev(blk);
 189
 190     if (has_attached_device && !blk_dev_has_removable_media(blk)) {
 191         error_setg(errp, "Device '%s' is not removable", device ?: id);
 192         return;
 193     }
 194
 195     if (has_attached_device && blk_dev_has_tray(blk) &&
 196         !blk_dev_is_tray_open(blk))
 197     {
 198         error_setg(errp, "Tray of device '%s' is not open", device ?: id);
 199         return;
 200     }
 201
 202     bs = blk_bs(blk);
 203     if (!bs) {
 204         return;
 205     }
 206
 207     aio_context = bdrv_get_aio_context(bs);
 208     aio_context_acquire(aio_context);
 209
 210     bdrv_graph_rdlock_main_loop();
 211     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
 212         bdrv_graph_rdunlock_main_loop();
 213         goto out;
 214     }
 215     bdrv_graph_rdunlock_main_loop();
 216
 217     blk_remove_bs(blk);
 218
 219     if (!blk_dev_has_tray(blk)) {
 220         /* For tray-less devices, blockdev-open-tray is a no-op (or may not be
 221          * called at all); therefore, the medium needs to be ejected here.
 222          * Do it after blk_remove_bs() so blk_is_inserted(blk) returns the @load
 223          * value passed here (i.e. false). */
 224         blk_dev_change_media_cb(blk, false, &error_abort);
 225     }
 226
 227 out:
 228     aio_context_release(aio_context);
 229 }
 230
 231 void qmp_blockdev_remove_medium(const char *id, Error **errp)
 232 {
 233     blockdev_remove_medium(NULL, id, errp);
 234 }
 235
 236 static void qmp_blockdev_insert_anon_medium(BlockBackend *blk,
 237                                             BlockDriverState *bs, Error **errp)
 238 {
 239     Error *local_err = NULL;
 240     bool has_device;
 241     int ret;
 242
 243     /* For BBs without a device, we can exchange the BDS tree at will */
 244     has_device = blk_get_attached_dev(blk);
 245
 246     if (has_device && !blk_dev_has_removable_media(blk)) {
 247         error_setg(errp, "Device is not removable");
 248         return;
 249     }
 250
 251     if (has_device && blk_dev_has_tray(blk) && !blk_dev_is_tray_open(blk)) {
 252         error_setg(errp, "Tray of the device is not open");
 253         return;
 254     }
 255
 256     if (blk_bs(blk)) {
 257         error_setg(errp, "There already is a medium in the device");
 258         return;
 259     }
 260
 261     ret = blk_insert_bs(blk, bs, errp);
 262     if (ret < 0) {
 263         return;
 264     }
 265
 266     if (!blk_dev_has_tray(blk)) {
 267         /* For tray-less devices, blockdev-close-tray is a no-op (or may not be
 268          * called at all); therefore, the medium needs to be pushed into the
 269          * slot here.
 270          * Do it after blk_insert_bs() so blk_is_inserted(blk) returns the @load
 271          * value passed here (i.e. true). */
 272         blk_dev_change_media_cb(blk, true, &local_err);
 273         if (local_err) {
 274             error_propagate(errp, local_err);
 275             blk_remove_bs(blk);
 276             return;
 277         }
 278     }
 279 }
 280
 281 static void blockdev_insert_medium(const char *device, const char *id,
 282                                    const char *node_name, Error **errp)
 283 {
 284     BlockBackend *blk;
 285     BlockDriverState *bs;
 286
 287     GRAPH_RDLOCK_GUARD_MAINLOOP();
 288
 289     blk = qmp_get_blk(device, id, errp);
 290     if (!blk) {
 291         return;
 292     }
 293
 294     bs = bdrv_find_node(node_name);
 295     if (!bs) {
 296         error_setg(errp, "Node '%s' not found", node_name);
 297         return;
 298     }
 299
 300     if (bdrv_has_blk(bs)) {
 301         error_setg(errp, "Node '%s' is already in use", node_name);
 302         return;
 303     }
 304
 305     qmp_blockdev_insert_anon_medium(blk, bs, errp);
 306 }
 307
 308 void qmp_blockdev_insert_medium(const char *id, const char *node_name,
 309                                 Error **errp)
 310 {
 311     blockdev_insert_medium(NULL, id, node_name, errp);
 312 }
 313
 314 void qmp_blockdev_change_medium(const char *device,
 315                                 const char *id,
 316                                 const char *filename,
 317                                 const char *format,
 318                                 bool has_force, bool force,
 319                                 bool has_read_only,
 320                                 BlockdevChangeReadOnlyMode read_only,
 321                                 Error **errp)
 322 {
 323     BlockBackend *blk;
 324     BlockDriverState *medium_bs = NULL;
 325     int bdrv_flags;
 326     bool detect_zeroes;
 327     int rc;
 328     QDict *options = NULL;
 329     Error *err = NULL;
 330
 331     blk = qmp_get_blk(device, id, errp);
 332     if (!blk) {
 333         goto fail;
 334     }
 335
 336     if (blk_bs(blk)) {
 337         blk_update_root_state(blk);
 338     }
 339
 340     bdrv_flags = blk_get_open_flags_from_root_state(blk);
 341     bdrv_flags &= ~(BDRV_O_TEMPORARY | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING |
 342         BDRV_O_PROTOCOL | BDRV_O_AUTO_RDONLY);
 343
 344     if (!has_read_only) {
 345         read_only = BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN;
 346     }
 347
 348     switch (read_only) {
 349     case BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN:
 350         break;
 351
 352     case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_ONLY:
 353         bdrv_flags &= ~BDRV_O_RDWR;
 354         break;
 355
 356     case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_WRITE:
 357         bdrv_flags |= BDRV_O_RDWR;
 358         break;
 359
 360     default:
 361         abort();
 362     }
 363
 364     options = qdict_new();
 365     detect_zeroes = blk_get_detect_zeroes_from_root_state(blk);
 366     qdict_put_str(options, "detect-zeroes", detect_zeroes ? "on" : "off");
 367
 368     if (format) {
 369         qdict_put_str(options, "driver", format);
 370     }
 371
 372     aio_context_acquire(qemu_get_aio_context());
 373     medium_bs = bdrv_open(filename, NULL, options, bdrv_flags, errp);
 374     aio_context_release(qemu_get_aio_context());
 375
 376     if (!medium_bs) {
 377         goto fail;
 378     }
 379
 380     rc = do_open_tray(device, id, force, &err);
 381     if (rc && rc != -ENOSYS) {
 382         error_propagate(errp, err);
 383         goto fail;
 384     }
 385     error_free(err);
 386     err = NULL;
 387
 388     blockdev_remove_medium(device, id, &err);
 389     if (err) {
 390         error_propagate(errp, err);
 391         goto fail;
 392     }
 393
 394     qmp_blockdev_insert_anon_medium(blk, medium_bs, &err);
 395     if (err) {
 396         error_propagate(errp, err);
 397         goto fail;
 398     }
 399
 400     qmp_blockdev_close_tray(device, id, errp);
 401
 402 fail:
 403     /* If the medium has been inserted, the device has its own reference, so
 404      * ours must be relinquished; and if it has not been inserted successfully,
 405      * the reference must be relinquished anyway */
 406     bdrv_unref(medium_bs);
 407 }
 408
 409 void qmp_eject(const char *device, const char *id,
 410                bool has_force, bool force, Error **errp)
 411 {
 412     Error *local_err = NULL;
 413     int rc;
 414
 415     if (!has_force) {
 416         force = false;
 417     }
 418
 419     rc = do_open_tray(device, id, force, &local_err);
 420     if (rc && rc != -ENOSYS) {
 421         error_propagate(errp, local_err);
 422         return;
 423     }
 424     error_free(local_err);
 425
 426     blockdev_remove_medium(device, id, errp);
 427 }
 428
 429 /* throttling disk I/O limits */
 430 void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
 431 {
 432     ThrottleConfig cfg;
 433     BlockDriverState *bs;
 434     BlockBackend *blk;
 435     AioContext *aio_context;
 436
 437     blk = qmp_get_blk(arg->device, arg->id, errp);
 438     if (!blk) {
 439         return;
 440     }
 441
 442     aio_context = blk_get_aio_context(blk);
 443     aio_context_acquire(aio_context);
 444
 445     bs = blk_bs(blk);
 446     if (!bs) {
 447         error_setg(errp, "Device has no medium");
 448         goto out;
 449     }
 450
 451     throttle_config_init(&cfg);
 452     cfg.buckets[THROTTLE_BPS_TOTAL].avg = arg->bps;
 453     cfg.buckets[THROTTLE_BPS_READ].avg  = arg->bps_rd;
 454     cfg.buckets[THROTTLE_BPS_WRITE].avg = arg->bps_wr;
 455
 456     cfg.buckets[THROTTLE_OPS_TOTAL].avg = arg->iops;
 457     cfg.buckets[THROTTLE_OPS_READ].avg  = arg->iops_rd;
 458     cfg.buckets[THROTTLE_OPS_WRITE].avg = arg->iops_wr;
 459
 460     if (arg->has_bps_max) {
 461         cfg.buckets[THROTTLE_BPS_TOTAL].max = arg->bps_max;
 462     }
 463     if (arg->has_bps_rd_max) {
 464         cfg.buckets[THROTTLE_BPS_READ].max = arg->bps_rd_max;
 465     }
 466     if (arg->has_bps_wr_max) {
 467         cfg.buckets[THROTTLE_BPS_WRITE].max = arg->bps_wr_max;
 468     }
 469     if (arg->has_iops_max) {
 470         cfg.buckets[THROTTLE_OPS_TOTAL].max = arg->iops_max;
 471     }
 472     if (arg->has_iops_rd_max) {
 473         cfg.buckets[THROTTLE_OPS_READ].max = arg->iops_rd_max;
 474     }
 475     if (arg->has_iops_wr_max) {
 476         cfg.buckets[THROTTLE_OPS_WRITE].max = arg->iops_wr_max;
 477     }
 478
 479     if (arg->has_bps_max_length) {
 480         cfg.buckets[THROTTLE_BPS_TOTAL].burst_length = arg->bps_max_length;
 481     }
 482     if (arg->has_bps_rd_max_length) {
 483         cfg.buckets[THROTTLE_BPS_READ].burst_length = arg->bps_rd_max_length;
 484     }
 485     if (arg->has_bps_wr_max_length) {
 486         cfg.buckets[THROTTLE_BPS_WRITE].burst_length = arg->bps_wr_max_length;
 487     }
 488     if (arg->has_iops_max_length) {
 489         cfg.buckets[THROTTLE_OPS_TOTAL].burst_length = arg->iops_max_length;
 490     }
 491     if (arg->has_iops_rd_max_length) {
 492         cfg.buckets[THROTTLE_OPS_READ].burst_length = arg->iops_rd_max_length;
 493     }
 494     if (arg->has_iops_wr_max_length) {
 495         cfg.buckets[THROTTLE_OPS_WRITE].burst_length = arg->iops_wr_max_length;
 496     }
 497
 498     if (arg->has_iops_size) {
 499         cfg.op_size = arg->iops_size;
 500     }
 501
 502     if (!throttle_is_valid(&cfg, errp)) {
 503         goto out;
 504     }
 505
 506     if (throttle_enabled(&cfg)) {
 507         /* Enable I/O limits if they're not enabled yet, otherwise
 508          * just update the throttling group. */
 509         if (!blk_get_public(blk)->throttle_group_member.throttle_state) {
 510             blk_io_limits_enable(blk, arg->group ?: arg->device ?: arg->id);
 511         } else if (arg->group) {
 512             blk_io_limits_update_group(blk, arg->group);
 513         }
 514         /* Set the new throttling configuration */
 515         blk_set_io_limits(blk, &cfg);
 516     } else if (blk_get_public(blk)->throttle_group_member.throttle_state) {
 517         /* If all throttling settings are set to 0, disable I/O limits */
 518         blk_io_limits_disable(blk);
 519     }
 520
 521 out:
 522     aio_context_release(aio_context);
 523 }
 524
 525 void qmp_block_latency_histogram_set(
 526     const char *id,
 527     bool has_boundaries, uint64List *boundaries,
 528     bool has_boundaries_read, uint64List *boundaries_read,
 529     bool has_boundaries_write, uint64List *boundaries_write,
 530     bool has_boundaries_append, uint64List *boundaries_append,
 531     bool has_boundaries_flush, uint64List *boundaries_flush,
 532     Error **errp)
 533 {
 534     BlockBackend *blk = qmp_get_blk(NULL, id, errp);
 535     BlockAcctStats *stats;
 536     int ret;
 537
 538     if (!blk) {
 539         return;
 540     }
 541
 542     stats = blk_get_stats(blk);
 543
 544     if (!has_boundaries && !has_boundaries_read && !has_boundaries_write &&
 545         !has_boundaries_flush)
 546     {
 547         block_latency_histograms_clear(stats);
 548         return;
 549     }
 550
 551     if (has_boundaries || has_boundaries_read) {
 552         ret = block_latency_histogram_set(
 553             stats, BLOCK_ACCT_READ,
 554             has_boundaries_read ? boundaries_read : boundaries);
 555         if (ret) {
 556             error_setg(errp, "Device '%s' set read boundaries fail", id);
 557             return;
 558         }
 559     }
 560
 561     if (has_boundaries || has_boundaries_write) {
 562         ret = block_latency_histogram_set(
 563             stats, BLOCK_ACCT_WRITE,
 564             has_boundaries_write ? boundaries_write : boundaries);
 565         if (ret) {
 566             error_setg(errp, "Device '%s' set write boundaries fail", id);
 567             return;
 568         }
 569     }
 570
 571     if (has_boundaries || has_boundaries_append) {
 572         ret = block_latency_histogram_set(
 573                 stats, BLOCK_ACCT_ZONE_APPEND,
 574                 has_boundaries_append ? boundaries_append : boundaries);
 575         if (ret) {
 576             error_setg(errp, "Device '%s' set append write boundaries fail", id);
 577             return;
 578         }
 579     }
 580
 581     if (has_boundaries || has_boundaries_flush) {
 582         ret = block_latency_histogram_set(
 583             stats, BLOCK_ACCT_FLUSH,
 584             has_boundaries_flush ? boundaries_flush : boundaries);
 585         if (ret) {
 586             error_setg(errp, "Device '%s' set flush boundaries fail", id);
 587             return;
 588         }
 589     }
 590 }