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     bool has_attached_device;
 178
 179     GLOBAL_STATE_CODE();
 180
 181     blk = qmp_get_blk(device, id, errp);
 182     if (!blk) {
 183         return;
 184     }
 185
 186     /* For BBs without a device, we can exchange the BDS tree at will */
 187     has_attached_device = blk_get_attached_dev(blk);
 188
 189     if (has_attached_device && !blk_dev_has_removable_media(blk)) {
 190         error_setg(errp, "Device '%s' is not removable", device ?: id);
 191         return;
 192     }
 193
 194     if (has_attached_device && blk_dev_has_tray(blk) &&
 195         !blk_dev_is_tray_open(blk))
 196     {
 197         error_setg(errp, "Tray of device '%s' is not open", device ?: id);
 198         return;
 199     }
 200
 201     bs = blk_bs(blk);
 202     if (!bs) {
 203         return;
 204     }
 205
 206     bdrv_graph_rdlock_main_loop();
 207     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
 208         bdrv_graph_rdunlock_main_loop();
 209         return;
 210     }
 211     bdrv_graph_rdunlock_main_loop();
 212
 213     blk_remove_bs(blk);
 214
 215     if (!blk_dev_has_tray(blk)) {
 216         /* For tray-less devices, blockdev-open-tray is a no-op (or may not be
 217          * called at all); therefore, the medium needs to be ejected here.
 218          * Do it after blk_remove_bs() so blk_is_inserted(blk) returns the @load
 219          * value passed here (i.e. false). */
 220         blk_dev_change_media_cb(blk, false, &error_abort);
 221     }
 222 }
 223
 224 void qmp_blockdev_remove_medium(const char *id, Error **errp)
 225 {
 226     blockdev_remove_medium(NULL, id, errp);
 227 }
 228
 229 static void qmp_blockdev_insert_anon_medium(BlockBackend *blk,
 230                                             BlockDriverState *bs, Error **errp)
 231 {
 232     Error *local_err = NULL;
 233     bool has_device;
 234     int ret;
 235
 236     /* For BBs without a device, we can exchange the BDS tree at will */
 237     has_device = blk_get_attached_dev(blk);
 238
 239     if (has_device && !blk_dev_has_removable_media(blk)) {
 240         error_setg(errp, "Device is not removable");
 241         return;
 242     }
 243
 244     if (has_device && blk_dev_has_tray(blk) && !blk_dev_is_tray_open(blk)) {
 245         error_setg(errp, "Tray of the device is not open");
 246         return;
 247     }
 248
 249     if (blk_bs(blk)) {
 250         error_setg(errp, "There already is a medium in the device");
 251         return;
 252     }
 253
 254     ret = blk_insert_bs(blk, bs, errp);
 255     if (ret < 0) {
 256         return;
 257     }
 258
 259     if (!blk_dev_has_tray(blk)) {
 260         /* For tray-less devices, blockdev-close-tray is a no-op (or may not be
 261          * called at all); therefore, the medium needs to be pushed into the
 262          * slot here.
 263          * Do it after blk_insert_bs() so blk_is_inserted(blk) returns the @load
 264          * value passed here (i.e. true). */
 265         blk_dev_change_media_cb(blk, true, &local_err);
 266         if (local_err) {
 267             error_propagate(errp, local_err);
 268             blk_remove_bs(blk);
 269             return;
 270         }
 271     }
 272 }
 273
 274 static void blockdev_insert_medium(const char *device, const char *id,
 275                                    const char *node_name, Error **errp)
 276 {
 277     BlockBackend *blk;
 278     BlockDriverState *bs;
 279
 280     GRAPH_RDLOCK_GUARD_MAINLOOP();
 281
 282     blk = qmp_get_blk(device, id, errp);
 283     if (!blk) {
 284         return;
 285     }
 286
 287     bs = bdrv_find_node(node_name);
 288     if (!bs) {
 289         error_setg(errp, "Node '%s' not found", node_name);
 290         return;
 291     }
 292
 293     if (bdrv_has_blk(bs)) {
 294         error_setg(errp, "Node '%s' is already in use", node_name);
 295         return;
 296     }
 297
 298     qmp_blockdev_insert_anon_medium(blk, bs, errp);
 299 }
 300
 301 void qmp_blockdev_insert_medium(const char *id, const char *node_name,
 302                                 Error **errp)
 303 {
 304     blockdev_insert_medium(NULL, id, node_name, errp);
 305 }
 306
 307 void qmp_blockdev_change_medium(const char *device,
 308                                 const char *id,
 309                                 const char *filename,
 310                                 const char *format,
 311                                 bool has_force, bool force,
 312                                 bool has_read_only,
 313                                 BlockdevChangeReadOnlyMode read_only,
 314                                 Error **errp)
 315 {
 316     BlockBackend *blk;
 317     BlockDriverState *medium_bs = NULL;
 318     int bdrv_flags;
 319     bool detect_zeroes;
 320     int rc;
 321     QDict *options = NULL;
 322     Error *err = NULL;
 323
 324     blk = qmp_get_blk(device, id, errp);
 325     if (!blk) {
 326         goto fail;
 327     }
 328
 329     if (blk_bs(blk)) {
 330         blk_update_root_state(blk);
 331     }
 332
 333     bdrv_flags = blk_get_open_flags_from_root_state(blk);
 334     bdrv_flags &= ~(BDRV_O_TEMPORARY | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING |
 335         BDRV_O_PROTOCOL | BDRV_O_AUTO_RDONLY);
 336
 337     if (!has_read_only) {
 338         read_only = BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN;
 339     }
 340
 341     switch (read_only) {
 342     case BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN:
 343         break;
 344
 345     case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_ONLY:
 346         bdrv_flags &= ~BDRV_O_RDWR;
 347         break;
 348
 349     case BLOCKDEV_CHANGE_READ_ONLY_MODE_READ_WRITE:
 350         bdrv_flags |= BDRV_O_RDWR;
 351         break;
 352
 353     default:
 354         abort();
 355     }
 356
 357     options = qdict_new();
 358     detect_zeroes = blk_get_detect_zeroes_from_root_state(blk);
 359     qdict_put_str(options, "detect-zeroes", detect_zeroes ? "on" : "off");
 360
 361     if (format) {
 362         qdict_put_str(options, "driver", format);
 363     }
 364
 365     medium_bs = bdrv_open(filename, NULL, options, bdrv_flags, errp);
 366
 367     if (!medium_bs) {
 368         goto fail;
 369     }
 370
 371     rc = do_open_tray(device, id, force, &err);
 372     if (rc && rc != -ENOSYS) {
 373         error_propagate(errp, err);
 374         goto fail;
 375     }
 376     error_free(err);
 377     err = NULL;
 378
 379     blockdev_remove_medium(device, id, &err);
 380     if (err) {
 381         error_propagate(errp, err);
 382         goto fail;
 383     }
 384
 385     qmp_blockdev_insert_anon_medium(blk, medium_bs, &err);
 386     if (err) {
 387         error_propagate(errp, err);
 388         goto fail;
 389     }
 390
 391     qmp_blockdev_close_tray(device, id, errp);
 392
 393 fail:
 394     /* If the medium has been inserted, the device has its own reference, so
 395      * ours must be relinquished; and if it has not been inserted successfully,
 396      * the reference must be relinquished anyway */
 397     bdrv_unref(medium_bs);
 398 }
 399
 400 void qmp_eject(const char *device, const char *id,
 401                bool has_force, bool force, Error **errp)
 402 {
 403     Error *local_err = NULL;
 404     int rc;
 405
 406     if (!has_force) {
 407         force = false;
 408     }
 409
 410     rc = do_open_tray(device, id, force, &local_err);
 411     if (rc && rc != -ENOSYS) {
 412         error_propagate(errp, local_err);
 413         return;
 414     }
 415     error_free(local_err);
 416
 417     blockdev_remove_medium(device, id, errp);
 418 }
 419
 420 /* throttling disk I/O limits */
 421 void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
 422 {
 423     ThrottleConfig cfg;
 424     BlockDriverState *bs;
 425     BlockBackend *blk;
 426
 427     blk = qmp_get_blk(arg->device, arg->id, errp);
 428     if (!blk) {
 429         return;
 430     }
 431
 432     bs = blk_bs(blk);
 433     if (!bs) {
 434         error_setg(errp, "Device has no medium");
 435         return;
 436     }
 437
 438     throttle_config_init(&cfg);
 439     cfg.buckets[THROTTLE_BPS_TOTAL].avg = arg->bps;
 440     cfg.buckets[THROTTLE_BPS_READ].avg  = arg->bps_rd;
 441     cfg.buckets[THROTTLE_BPS_WRITE].avg = arg->bps_wr;
 442
 443     cfg.buckets[THROTTLE_OPS_TOTAL].avg = arg->iops;
 444     cfg.buckets[THROTTLE_OPS_READ].avg  = arg->iops_rd;
 445     cfg.buckets[THROTTLE_OPS_WRITE].avg = arg->iops_wr;
 446
 447     if (arg->has_bps_max) {
 448         cfg.buckets[THROTTLE_BPS_TOTAL].max = arg->bps_max;
 449     }
 450     if (arg->has_bps_rd_max) {
 451         cfg.buckets[THROTTLE_BPS_READ].max = arg->bps_rd_max;
 452     }
 453     if (arg->has_bps_wr_max) {
 454         cfg.buckets[THROTTLE_BPS_WRITE].max = arg->bps_wr_max;
 455     }
 456     if (arg->has_iops_max) {
 457         cfg.buckets[THROTTLE_OPS_TOTAL].max = arg->iops_max;
 458     }
 459     if (arg->has_iops_rd_max) {
 460         cfg.buckets[THROTTLE_OPS_READ].max = arg->iops_rd_max;
 461     }
 462     if (arg->has_iops_wr_max) {
 463         cfg.buckets[THROTTLE_OPS_WRITE].max = arg->iops_wr_max;
 464     }
 465
 466     if (arg->has_bps_max_length) {
 467         cfg.buckets[THROTTLE_BPS_TOTAL].burst_length = arg->bps_max_length;
 468     }
 469     if (arg->has_bps_rd_max_length) {
 470         cfg.buckets[THROTTLE_BPS_READ].burst_length = arg->bps_rd_max_length;
 471     }
 472     if (arg->has_bps_wr_max_length) {
 473         cfg.buckets[THROTTLE_BPS_WRITE].burst_length = arg->bps_wr_max_length;
 474     }
 475     if (arg->has_iops_max_length) {
 476         cfg.buckets[THROTTLE_OPS_TOTAL].burst_length = arg->iops_max_length;
 477     }
 478     if (arg->has_iops_rd_max_length) {
 479         cfg.buckets[THROTTLE_OPS_READ].burst_length = arg->iops_rd_max_length;
 480     }
 481     if (arg->has_iops_wr_max_length) {
 482         cfg.buckets[THROTTLE_OPS_WRITE].burst_length = arg->iops_wr_max_length;
 483     }
 484
 485     if (arg->has_iops_size) {
 486         cfg.op_size = arg->iops_size;
 487     }
 488
 489     if (!throttle_is_valid(&cfg, errp)) {
 490         return;
 491     }
 492
 493     if (throttle_enabled(&cfg)) {
 494         /* Enable I/O limits if they're not enabled yet, otherwise
 495          * just update the throttling group. */
 496         if (!blk_get_public(blk)->throttle_group_member.throttle_state) {
 497             blk_io_limits_enable(blk, arg->group ?: arg->device ?: arg->id);
 498         } else if (arg->group) {
 499             blk_io_limits_update_group(blk, arg->group);
 500         }
 501         /* Set the new throttling configuration */
 502         blk_set_io_limits(blk, &cfg);
 503     } else if (blk_get_public(blk)->throttle_group_member.throttle_state) {
 504         /* If all throttling settings are set to 0, disable I/O limits */
 505         blk_io_limits_disable(blk);
 506     }
 507 }
 508
 509 void qmp_block_latency_histogram_set(
 510     const char *id,
 511     bool has_boundaries, uint64List *boundaries,
 512     bool has_boundaries_read, uint64List *boundaries_read,
 513     bool has_boundaries_write, uint64List *boundaries_write,
 514     bool has_boundaries_append, uint64List *boundaries_append,
 515     bool has_boundaries_flush, uint64List *boundaries_flush,
 516     Error **errp)
 517 {
 518     BlockBackend *blk = qmp_get_blk(NULL, id, errp);
 519     BlockAcctStats *stats;
 520     int ret;
 521
 522     if (!blk) {
 523         return;
 524     }
 525
 526     stats = blk_get_stats(blk);
 527
 528     if (!has_boundaries && !has_boundaries_read && !has_boundaries_write &&
 529         !has_boundaries_flush)
 530     {
 531         block_latency_histograms_clear(stats);
 532         return;
 533     }
 534
 535     if (has_boundaries || has_boundaries_read) {
 536         ret = block_latency_histogram_set(
 537             stats, BLOCK_ACCT_READ,
 538             has_boundaries_read ? boundaries_read : boundaries);
 539         if (ret) {
 540             error_setg(errp, "Device '%s' set read boundaries fail", id);
 541             return;
 542         }
 543     }
 544
 545     if (has_boundaries || has_boundaries_write) {
 546         ret = block_latency_histogram_set(
 547             stats, BLOCK_ACCT_WRITE,
 548             has_boundaries_write ? boundaries_write : boundaries);
 549         if (ret) {
 550             error_setg(errp, "Device '%s' set write boundaries fail", id);
 551             return;
 552         }
 553     }
 554
 555     if (has_boundaries || has_boundaries_append) {
 556         ret = block_latency_histogram_set(
 557                 stats, BLOCK_ACCT_ZONE_APPEND,
 558                 has_boundaries_append ? boundaries_append : boundaries);
 559         if (ret) {
 560             error_setg(errp, "Device '%s' set append write boundaries fail", id);
 561             return;
 562         }
 563     }
 564
 565     if (has_boundaries || has_boundaries_flush) {
 566         ret = block_latency_histogram_set(
 567             stats, BLOCK_ACCT_FLUSH,
 568             has_boundaries_flush ? boundaries_flush : boundaries);
 569         if (ret) {
 570             error_setg(errp, "Device '%s' set flush boundaries fail", id);
 571             return;
 572         }
 573     }
 574 }