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 blockdev_remove_medium(const char *device, const char *id,
 173                                    Error **errp)
 174 {
 175     BlockBackend *blk;
 176     BlockDriverState *bs;
 177     AioContext *aio_context;
 178     bool has_attached_device;
 179
 180     blk = qmp_get_blk(device, id, errp);
 181     if (!blk) {
 182         return;
 183     }
 184
 185     /* For BBs without a device, we can exchange the BDS tree at will */
 186     has_attached_device = blk_get_attached_dev(blk);
 187
 188     if (has_attached_device && !blk_dev_has_removable_media(blk)) {
 189         error_setg(errp, "Device '%s' is not removable", device ?: id);
 190         return;
 191     }
 192
 193     if (has_attached_device && blk_dev_has_tray(blk) &&
 194         !blk_dev_is_tray_open(blk))
 195     {
 196         error_setg(errp, "Tray of device '%s' is not open", device ?: id);
 197         return;
 198     }
 199
 200     bs = blk_bs(blk);
 201     if (!bs) {
 202         return;
 203     }
 204
 205     aio_context = bdrv_get_aio_context(bs);
 206     aio_context_acquire(aio_context);
 207
 208     if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
 209         goto out;
 210     }
 211
 212     blk_remove_bs(blk);
 213
 214     if (!blk_dev_has_tray(blk)) {
 215         /* For tray-less devices, blockdev-open-tray is a no-op (or may not be
 216          * called at all); therefore, the medium needs to be ejected here.
 217          * Do it after blk_remove_bs() so blk_is_inserted(blk) returns the @load
 218          * value passed here (i.e. false). */
 219         blk_dev_change_media_cb(blk, false, &error_abort);
 220     }
 221
 222 out:
 223     aio_context_release(aio_context);
 224 }
 225
 226 void qmp_blockdev_remove_medium(const char *id, Error **errp)
 227 {
 228     blockdev_remove_medium(NULL, id, errp);
 229 }
 230
 231 static void qmp_blockdev_insert_anon_medium(BlockBackend *blk,
 232                                             BlockDriverState *bs, Error **errp)
 233 {
 234     Error *local_err = NULL;
 235     bool has_device;
 236     int ret;
 237
 238     /* For BBs without a device, we can exchange the BDS tree at will */
 239     has_device = blk_get_attached_dev(blk);
 240
 241     if (has_device && !blk_dev_has_removable_media(blk)) {
 242         error_setg(errp, "Device is not removable");
 243         return;
 244     }
 245
 246     if (has_device && blk_dev_has_tray(blk) && !blk_dev_is_tray_open(blk)) {
 247         error_setg(errp, "Tray of the device is not open");
 248         return;
 249     }
 250
 251     if (blk_bs(blk)) {
 252         error_setg(errp, "There already is a medium in the device");
 253         return;
 254     }
 255
 256     ret = blk_insert_bs(blk, bs, errp);
 257     if (ret < 0) {
 258         return;
 259     }
 260
 261     if (!blk_dev_has_tray(blk)) {
 262         /* For tray-less devices, blockdev-close-tray is a no-op (or may not be
 263          * called at all); therefore, the medium needs to be pushed into the
 264          * slot here.
 265          * Do it after blk_insert_bs() so blk_is_inserted(blk) returns the @load
 266          * value passed here (i.e. true). */
 267         blk_dev_change_media_cb(blk, true, &local_err);
 268         if (local_err) {
 269             error_propagate(errp, local_err);
 270             blk_remove_bs(blk);
 271             return;
 272         }
 273     }
 274 }
 275
 276 static void blockdev_insert_medium(const char *device, const char *id,
 277                                    const char *node_name, Error **errp)
 278 {
 279     BlockBackend *blk;
 280     BlockDriverState *bs;
 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     if (!medium_bs) {
 367         goto fail;
 368     }
 369
 370     rc = do_open_tray(device, id, force, &err);
 371     if (rc && rc != -ENOSYS) {
 372         error_propagate(errp, err);
 373         goto fail;
 374     }
 375     error_free(err);
 376     err = NULL;
 377
 378     blockdev_remove_medium(device, id, &err);
 379     if (err) {
 380         error_propagate(errp, err);
 381         goto fail;
 382     }
 383
 384     qmp_blockdev_insert_anon_medium(blk, medium_bs, &err);
 385     if (err) {
 386         error_propagate(errp, err);
 387         goto fail;
 388     }
 389
 390     qmp_blockdev_close_tray(device, id, errp);
 391
 392 fail:
 393     /* If the medium has been inserted, the device has its own reference, so
 394      * ours must be relinquished; and if it has not been inserted successfully,
 395      * the reference must be relinquished anyway */
 396     bdrv_unref(medium_bs);
 397 }
 398
 399 void qmp_eject(const char *device, const char *id,
 400                bool has_force, bool force, Error **errp)
 401 {
 402     Error *local_err = NULL;
 403     int rc;
 404
 405     if (!has_force) {
 406         force = false;
 407     }
 408
 409     rc = do_open_tray(device, id, force, &local_err);
 410     if (rc && rc != -ENOSYS) {
 411         error_propagate(errp, local_err);
 412         return;
 413     }
 414     error_free(local_err);
 415
 416     blockdev_remove_medium(device, id, errp);
 417 }
 418
 419 /* throttling disk I/O limits */
 420 void qmp_block_set_io_throttle(BlockIOThrottle *arg, Error **errp)
 421 {
 422     ThrottleConfig cfg;
 423     BlockDriverState *bs;
 424     BlockBackend *blk;
 425     AioContext *aio_context;
 426
 427     blk = qmp_get_blk(arg->device, arg->id, errp);
 428     if (!blk) {
 429         return;
 430     }
 431
 432     aio_context = blk_get_aio_context(blk);
 433     aio_context_acquire(aio_context);
 434
 435     bs = blk_bs(blk);
 436     if (!bs) {
 437         error_setg(errp, "Device has no medium");
 438         goto out;
 439     }
 440
 441     throttle_config_init(&cfg);
 442     cfg.buckets[THROTTLE_BPS_TOTAL].avg = arg->bps;
 443     cfg.buckets[THROTTLE_BPS_READ].avg  = arg->bps_rd;
 444     cfg.buckets[THROTTLE_BPS_WRITE].avg = arg->bps_wr;
 445
 446     cfg.buckets[THROTTLE_OPS_TOTAL].avg = arg->iops;
 447     cfg.buckets[THROTTLE_OPS_READ].avg  = arg->iops_rd;
 448     cfg.buckets[THROTTLE_OPS_WRITE].avg = arg->iops_wr;
 449
 450     if (arg->has_bps_max) {
 451         cfg.buckets[THROTTLE_BPS_TOTAL].max = arg->bps_max;
 452     }
 453     if (arg->has_bps_rd_max) {
 454         cfg.buckets[THROTTLE_BPS_READ].max = arg->bps_rd_max;
 455     }
 456     if (arg->has_bps_wr_max) {
 457         cfg.buckets[THROTTLE_BPS_WRITE].max = arg->bps_wr_max;
 458     }
 459     if (arg->has_iops_max) {
 460         cfg.buckets[THROTTLE_OPS_TOTAL].max = arg->iops_max;
 461     }
 462     if (arg->has_iops_rd_max) {
 463         cfg.buckets[THROTTLE_OPS_READ].max = arg->iops_rd_max;
 464     }
 465     if (arg->has_iops_wr_max) {
 466         cfg.buckets[THROTTLE_OPS_WRITE].max = arg->iops_wr_max;
 467     }
 468
 469     if (arg->has_bps_max_length) {
 470         cfg.buckets[THROTTLE_BPS_TOTAL].burst_length = arg->bps_max_length;
 471     }
 472     if (arg->has_bps_rd_max_length) {
 473         cfg.buckets[THROTTLE_BPS_READ].burst_length = arg->bps_rd_max_length;
 474     }
 475     if (arg->has_bps_wr_max_length) {
 476         cfg.buckets[THROTTLE_BPS_WRITE].burst_length = arg->bps_wr_max_length;
 477     }
 478     if (arg->has_iops_max_length) {
 479         cfg.buckets[THROTTLE_OPS_TOTAL].burst_length = arg->iops_max_length;
 480     }
 481     if (arg->has_iops_rd_max_length) {
 482         cfg.buckets[THROTTLE_OPS_READ].burst_length = arg->iops_rd_max_length;
 483     }
 484     if (arg->has_iops_wr_max_length) {
 485         cfg.buckets[THROTTLE_OPS_WRITE].burst_length = arg->iops_wr_max_length;
 486     }
 487
 488     if (arg->has_iops_size) {
 489         cfg.op_size = arg->iops_size;
 490     }
 491
 492     if (!throttle_is_valid(&cfg, errp)) {
 493         goto out;
 494     }
 495
 496     if (throttle_enabled(&cfg)) {
 497         /* Enable I/O limits if they're not enabled yet, otherwise
 498          * just update the throttling group. */
 499         if (!blk_get_public(blk)->throttle_group_member.throttle_state) {
 500             blk_io_limits_enable(blk, arg->group ?: arg->device ?: arg->id);
 501         } else if (arg->group) {
 502             blk_io_limits_update_group(blk, arg->group);
 503         }
 504         /* Set the new throttling configuration */
 505         blk_set_io_limits(blk, &cfg);
 506     } else if (blk_get_public(blk)->throttle_group_member.throttle_state) {
 507         /* If all throttling settings are set to 0, disable I/O limits */
 508         blk_io_limits_disable(blk);
 509     }
 510
 511 out:
 512     aio_context_release(aio_context);
 513 }
 514
 515 void qmp_block_latency_histogram_set(
 516     const char *id,
 517     bool has_boundaries, uint64List *boundaries,
 518     bool has_boundaries_read, uint64List *boundaries_read,
 519     bool has_boundaries_write, uint64List *boundaries_write,
 520     bool has_boundaries_flush, uint64List *boundaries_flush,
 521     Error **errp)
 522 {
 523     BlockBackend *blk = qmp_get_blk(NULL, id, errp);
 524     BlockAcctStats *stats;
 525     int ret;
 526
 527     if (!blk) {
 528         return;
 529     }
 530
 531     stats = blk_get_stats(blk);
 532
 533     if (!has_boundaries && !has_boundaries_read && !has_boundaries_write &&
 534         !has_boundaries_flush)
 535     {
 536         block_latency_histograms_clear(stats);
 537         return;
 538     }
 539
 540     if (has_boundaries || has_boundaries_read) {
 541         ret = block_latency_histogram_set(
 542             stats, BLOCK_ACCT_READ,
 543             has_boundaries_read ? boundaries_read : boundaries);
 544         if (ret) {
 545             error_setg(errp, "Device '%s' set read boundaries fail", id);
 546             return;
 547         }
 548     }
 549
 550     if (has_boundaries || has_boundaries_write) {
 551         ret = block_latency_histogram_set(
 552             stats, BLOCK_ACCT_WRITE,
 553             has_boundaries_write ? boundaries_write : boundaries);
 554         if (ret) {
 555             error_setg(errp, "Device '%s' set write boundaries fail", id);
 556             return;
 557         }
 558     }
 559
 560     if (has_boundaries || has_boundaries_flush) {
 561         ret = block_latency_histogram_set(
 562             stats, BLOCK_ACCT_FLUSH,
 563             has_boundaries_flush ? boundaries_flush : boundaries);
 564         if (ret) {
 565             error_setg(errp, "Device '%s' set flush boundaries fail", id);
 566             return;
 567         }
 568     }
 569 }