tests/test-bdrv-drain.c

   1 /*
   2  * Block node draining tests
   3  *
   4  * Copyright (c) 2017 Kevin Wolf <[email protected]>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "block/block.h"
  27 #include "block/blockjob_int.h"
  28 #include "sysemu/block-backend.h"
  29 #include "qapi/error.h"
  30 #include "qemu/main-loop.h"
  31 #include "iothread.h"
  32
  33 static QemuEvent done_event;
  34
  35 typedef struct BDRVTestState {
  36     int drain_count;
  37     AioContext *bh_indirection_ctx;
  38     bool sleep_in_drain_begin;
  39 } BDRVTestState;
  40
  41 static void coroutine_fn bdrv_test_co_drain_begin(BlockDriverState *bs)
  42 {
  43     BDRVTestState *s = bs->opaque;
  44     s->drain_count++;
  45     if (s->sleep_in_drain_begin) {
  46         qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000);
  47     }
  48 }
  49
  50 static void coroutine_fn bdrv_test_co_drain_end(BlockDriverState *bs)
  51 {
  52     BDRVTestState *s = bs->opaque;
  53     s->drain_count--;
  54 }
  55
  56 static void bdrv_test_close(BlockDriverState *bs)
  57 {
  58     BDRVTestState *s = bs->opaque;
  59     g_assert_cmpint(s->drain_count, >, 0);
  60 }
  61
  62 static void co_reenter_bh(void *opaque)
  63 {
  64     aio_co_wake(opaque);
  65 }
  66
  67 static int coroutine_fn bdrv_test_co_preadv(BlockDriverState *bs,
  68                                             uint64_t offset, uint64_t bytes,
  69                                             QEMUIOVector *qiov, int flags)
  70 {
  71     BDRVTestState *s = bs->opaque;
  72
  73     /* We want this request to stay until the polling loop in drain waits for
  74      * it to complete. We need to sleep a while as bdrv_drain_invoke() comes
  75      * first and polls its result, too, but it shouldn't accidentally complete
  76      * this request yet. */
  77     qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000);
  78
  79     if (s->bh_indirection_ctx) {
  80         aio_bh_schedule_oneshot(s->bh_indirection_ctx, co_reenter_bh,
  81                                 qemu_coroutine_self());
  82         qemu_coroutine_yield();
  83     }
  84
  85     return 0;
  86 }
  87
  88 static void bdrv_test_child_perm(BlockDriverState *bs, BdrvChild *c,
  89                                  const BdrvChildRole *role,
  90                                  BlockReopenQueue *reopen_queue,
  91                                  uint64_t perm, uint64_t shared,
  92                                  uint64_t *nperm, uint64_t *nshared)
  93 {
  94     /* bdrv_format_default_perms() accepts only these two, so disguise
  95      * detach_by_driver_cb_role as one of them. */
  96     if (role != &child_file && role != &child_backing) {
  97         role = &child_file;
  98     }
  99
 100     bdrv_format_default_perms(bs, c, role, reopen_queue, perm, shared,
 101                               nperm, nshared);
 102 }
 103
 104 static BlockDriver bdrv_test = {
 105     .format_name            = "test",
 106     .instance_size          = sizeof(BDRVTestState),
 107
 108     .bdrv_close             = bdrv_test_close,
 109     .bdrv_co_preadv         = bdrv_test_co_preadv,
 110
 111     .bdrv_co_drain_begin    = bdrv_test_co_drain_begin,
 112     .bdrv_co_drain_end      = bdrv_test_co_drain_end,
 113
 114     .bdrv_child_perm        = bdrv_test_child_perm,
 115 };
 116
 117 static void aio_ret_cb(void *opaque, int ret)
 118 {
 119     int *aio_ret = opaque;
 120     *aio_ret = ret;
 121 }
 122
 123 typedef struct CallInCoroutineData {
 124     void (*entry)(void);
 125     bool done;
 126 } CallInCoroutineData;
 127
 128 static coroutine_fn void call_in_coroutine_entry(void *opaque)
 129 {
 130     CallInCoroutineData *data = opaque;
 131
 132     data->entry();
 133     data->done = true;
 134 }
 135
 136 static void call_in_coroutine(void (*entry)(void))
 137 {
 138     Coroutine *co;
 139     CallInCoroutineData data = {
 140         .entry  = entry,
 141         .done   = false,
 142     };
 143
 144     co = qemu_coroutine_create(call_in_coroutine_entry, &data);
 145     qemu_coroutine_enter(co);
 146     while (!data.done) {
 147         aio_poll(qemu_get_aio_context(), true);
 148     }
 149 }
 150
 151 enum drain_type {
 152     BDRV_DRAIN_ALL,
 153     BDRV_DRAIN,
 154     BDRV_SUBTREE_DRAIN,
 155     DRAIN_TYPE_MAX,
 156 };
 157
 158 static void do_drain_begin(enum drain_type drain_type, BlockDriverState *bs)
 159 {
 160     switch (drain_type) {
 161     case BDRV_DRAIN_ALL:        bdrv_drain_all_begin(); break;
 162     case BDRV_DRAIN:            bdrv_drained_begin(bs); break;
 163     case BDRV_SUBTREE_DRAIN:    bdrv_subtree_drained_begin(bs); break;
 164     default:                    g_assert_not_reached();
 165     }
 166 }
 167
 168 static void do_drain_end(enum drain_type drain_type, BlockDriverState *bs)
 169 {
 170     switch (drain_type) {
 171     case BDRV_DRAIN_ALL:        bdrv_drain_all_end(); break;
 172     case BDRV_DRAIN:            bdrv_drained_end(bs); break;
 173     case BDRV_SUBTREE_DRAIN:    bdrv_subtree_drained_end(bs); break;
 174     default:                    g_assert_not_reached();
 175     }
 176 }
 177
 178 static void do_drain_begin_unlocked(enum drain_type drain_type, BlockDriverState *bs)
 179 {
 180     if (drain_type != BDRV_DRAIN_ALL) {
 181         aio_context_acquire(bdrv_get_aio_context(bs));
 182     }
 183     do_drain_begin(drain_type, bs);
 184     if (drain_type != BDRV_DRAIN_ALL) {
 185         aio_context_release(bdrv_get_aio_context(bs));
 186     }
 187 }
 188
 189 static void do_drain_end_unlocked(enum drain_type drain_type, BlockDriverState *bs)
 190 {
 191     if (drain_type != BDRV_DRAIN_ALL) {
 192         aio_context_acquire(bdrv_get_aio_context(bs));
 193     }
 194     do_drain_end(drain_type, bs);
 195     if (drain_type != BDRV_DRAIN_ALL) {
 196         aio_context_release(bdrv_get_aio_context(bs));
 197     }
 198 }
 199
 200 static void test_drv_cb_common(enum drain_type drain_type, bool recursive)
 201 {
 202     BlockBackend *blk;
 203     BlockDriverState *bs, *backing;
 204     BDRVTestState *s, *backing_s;
 205     BlockAIOCB *acb;
 206     int aio_ret;
 207
 208     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, 0);
 209
 210     blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 211     bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR,
 212                               &error_abort);
 213     s = bs->opaque;
 214     blk_insert_bs(blk, bs, &error_abort);
 215
 216     backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort);
 217     backing_s = backing->opaque;
 218     bdrv_set_backing_hd(bs, backing, &error_abort);
 219
 220     /* Simple bdrv_drain_all_begin/end pair, check that CBs are called */
 221     g_assert_cmpint(s->drain_count, ==, 0);
 222     g_assert_cmpint(backing_s->drain_count, ==, 0);
 223
 224     do_drain_begin(drain_type, bs);
 225
 226     g_assert_cmpint(s->drain_count, ==, 1);
 227     g_assert_cmpint(backing_s->drain_count, ==, !!recursive);
 228
 229     do_drain_end(drain_type, bs);
 230
 231     g_assert_cmpint(s->drain_count, ==, 0);
 232     g_assert_cmpint(backing_s->drain_count, ==, 0);
 233
 234     /* Now do the same while a request is pending */
 235     aio_ret = -EINPROGRESS;
 236     acb = blk_aio_preadv(blk, 0, &qiov, 0, aio_ret_cb, &aio_ret);
 237     g_assert(acb != NULL);
 238     g_assert_cmpint(aio_ret, ==, -EINPROGRESS);
 239
 240     g_assert_cmpint(s->drain_count, ==, 0);
 241     g_assert_cmpint(backing_s->drain_count, ==, 0);
 242
 243     do_drain_begin(drain_type, bs);
 244
 245     g_assert_cmpint(aio_ret, ==, 0);
 246     g_assert_cmpint(s->drain_count, ==, 1);
 247     g_assert_cmpint(backing_s->drain_count, ==, !!recursive);
 248
 249     do_drain_end(drain_type, bs);
 250
 251     g_assert_cmpint(s->drain_count, ==, 0);
 252     g_assert_cmpint(backing_s->drain_count, ==, 0);
 253
 254     bdrv_unref(backing);
 255     bdrv_unref(bs);
 256     blk_unref(blk);
 257 }
 258
 259 static void test_drv_cb_drain_all(void)
 260 {
 261     test_drv_cb_common(BDRV_DRAIN_ALL, true);
 262 }
 263
 264 static void test_drv_cb_drain(void)
 265 {
 266     test_drv_cb_common(BDRV_DRAIN, false);
 267 }
 268
 269 static void test_drv_cb_drain_subtree(void)
 270 {
 271     test_drv_cb_common(BDRV_SUBTREE_DRAIN, true);
 272 }
 273
 274 static void test_drv_cb_co_drain_all(void)
 275 {
 276     call_in_coroutine(test_drv_cb_drain_all);
 277 }
 278
 279 static void test_drv_cb_co_drain(void)
 280 {
 281     call_in_coroutine(test_drv_cb_drain);
 282 }
 283
 284 static void test_drv_cb_co_drain_subtree(void)
 285 {
 286     call_in_coroutine(test_drv_cb_drain_subtree);
 287 }
 288
 289 static void test_quiesce_common(enum drain_type drain_type, bool recursive)
 290 {
 291     BlockBackend *blk;
 292     BlockDriverState *bs, *backing;
 293
 294     blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 295     bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR,
 296                               &error_abort);
 297     blk_insert_bs(blk, bs, &error_abort);
 298
 299     backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort);
 300     bdrv_set_backing_hd(bs, backing, &error_abort);
 301
 302     g_assert_cmpint(bs->quiesce_counter, ==, 0);
 303     g_assert_cmpint(backing->quiesce_counter, ==, 0);
 304
 305     do_drain_begin(drain_type, bs);
 306
 307     g_assert_cmpint(bs->quiesce_counter, ==, 1);
 308     g_assert_cmpint(backing->quiesce_counter, ==, !!recursive);
 309
 310     do_drain_end(drain_type, bs);
 311
 312     g_assert_cmpint(bs->quiesce_counter, ==, 0);
 313     g_assert_cmpint(backing->quiesce_counter, ==, 0);
 314
 315     bdrv_unref(backing);
 316     bdrv_unref(bs);
 317     blk_unref(blk);
 318 }
 319
 320 static void test_quiesce_drain_all(void)
 321 {
 322     test_quiesce_common(BDRV_DRAIN_ALL, true);
 323 }
 324
 325 static void test_quiesce_drain(void)
 326 {
 327     test_quiesce_common(BDRV_DRAIN, false);
 328 }
 329
 330 static void test_quiesce_drain_subtree(void)
 331 {
 332     test_quiesce_common(BDRV_SUBTREE_DRAIN, true);
 333 }
 334
 335 static void test_quiesce_co_drain_all(void)
 336 {
 337     call_in_coroutine(test_quiesce_drain_all);
 338 }
 339
 340 static void test_quiesce_co_drain(void)
 341 {
 342     call_in_coroutine(test_quiesce_drain);
 343 }
 344
 345 static void test_quiesce_co_drain_subtree(void)
 346 {
 347     call_in_coroutine(test_quiesce_drain_subtree);
 348 }
 349
 350 static void test_nested(void)
 351 {
 352     BlockBackend *blk;
 353     BlockDriverState *bs, *backing;
 354     BDRVTestState *s, *backing_s;
 355     enum drain_type outer, inner;
 356
 357     blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 358     bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR,
 359                               &error_abort);
 360     s = bs->opaque;
 361     blk_insert_bs(blk, bs, &error_abort);
 362
 363     backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort);
 364     backing_s = backing->opaque;
 365     bdrv_set_backing_hd(bs, backing, &error_abort);
 366
 367     for (outer = 0; outer < DRAIN_TYPE_MAX; outer++) {
 368         for (inner = 0; inner < DRAIN_TYPE_MAX; inner++) {
 369             int backing_quiesce = (outer != BDRV_DRAIN) +
 370                                   (inner != BDRV_DRAIN);
 371
 372             g_assert_cmpint(bs->quiesce_counter, ==, 0);
 373             g_assert_cmpint(backing->quiesce_counter, ==, 0);
 374             g_assert_cmpint(s->drain_count, ==, 0);
 375             g_assert_cmpint(backing_s->drain_count, ==, 0);
 376
 377             do_drain_begin(outer, bs);
 378             do_drain_begin(inner, bs);
 379
 380             g_assert_cmpint(bs->quiesce_counter, ==, 2);
 381             g_assert_cmpint(backing->quiesce_counter, ==, backing_quiesce);
 382             g_assert_cmpint(s->drain_count, ==, 2);
 383             g_assert_cmpint(backing_s->drain_count, ==, backing_quiesce);
 384
 385             do_drain_end(inner, bs);
 386             do_drain_end(outer, bs);
 387
 388             g_assert_cmpint(bs->quiesce_counter, ==, 0);
 389             g_assert_cmpint(backing->quiesce_counter, ==, 0);
 390             g_assert_cmpint(s->drain_count, ==, 0);
 391             g_assert_cmpint(backing_s->drain_count, ==, 0);
 392         }
 393     }
 394
 395     bdrv_unref(backing);
 396     bdrv_unref(bs);
 397     blk_unref(blk);
 398 }
 399
 400 static void test_multiparent(void)
 401 {
 402     BlockBackend *blk_a, *blk_b;
 403     BlockDriverState *bs_a, *bs_b, *backing;
 404     BDRVTestState *a_s, *b_s, *backing_s;
 405
 406     blk_a = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 407     bs_a = bdrv_new_open_driver(&bdrv_test, "test-node-a", BDRV_O_RDWR,
 408                                 &error_abort);
 409     a_s = bs_a->opaque;
 410     blk_insert_bs(blk_a, bs_a, &error_abort);
 411
 412     blk_b = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 413     bs_b = bdrv_new_open_driver(&bdrv_test, "test-node-b", BDRV_O_RDWR,
 414                                 &error_abort);
 415     b_s = bs_b->opaque;
 416     blk_insert_bs(blk_b, bs_b, &error_abort);
 417
 418     backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort);
 419     backing_s = backing->opaque;
 420     bdrv_set_backing_hd(bs_a, backing, &error_abort);
 421     bdrv_set_backing_hd(bs_b, backing, &error_abort);
 422
 423     g_assert_cmpint(bs_a->quiesce_counter, ==, 0);
 424     g_assert_cmpint(bs_b->quiesce_counter, ==, 0);
 425     g_assert_cmpint(backing->quiesce_counter, ==, 0);
 426     g_assert_cmpint(a_s->drain_count, ==, 0);
 427     g_assert_cmpint(b_s->drain_count, ==, 0);
 428     g_assert_cmpint(backing_s->drain_count, ==, 0);
 429
 430     do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a);
 431
 432     g_assert_cmpint(bs_a->quiesce_counter, ==, 1);
 433     g_assert_cmpint(bs_b->quiesce_counter, ==, 1);
 434     g_assert_cmpint(backing->quiesce_counter, ==, 1);
 435     g_assert_cmpint(a_s->drain_count, ==, 1);
 436     g_assert_cmpint(b_s->drain_count, ==, 1);
 437     g_assert_cmpint(backing_s->drain_count, ==, 1);
 438
 439     do_drain_begin(BDRV_SUBTREE_DRAIN, bs_b);
 440
 441     g_assert_cmpint(bs_a->quiesce_counter, ==, 2);
 442     g_assert_cmpint(bs_b->quiesce_counter, ==, 2);
 443     g_assert_cmpint(backing->quiesce_counter, ==, 2);
 444     g_assert_cmpint(a_s->drain_count, ==, 2);
 445     g_assert_cmpint(b_s->drain_count, ==, 2);
 446     g_assert_cmpint(backing_s->drain_count, ==, 2);
 447
 448     do_drain_end(BDRV_SUBTREE_DRAIN, bs_b);
 449
 450     g_assert_cmpint(bs_a->quiesce_counter, ==, 1);
 451     g_assert_cmpint(bs_b->quiesce_counter, ==, 1);
 452     g_assert_cmpint(backing->quiesce_counter, ==, 1);
 453     g_assert_cmpint(a_s->drain_count, ==, 1);
 454     g_assert_cmpint(b_s->drain_count, ==, 1);
 455     g_assert_cmpint(backing_s->drain_count, ==, 1);
 456
 457     do_drain_end(BDRV_SUBTREE_DRAIN, bs_a);
 458
 459     g_assert_cmpint(bs_a->quiesce_counter, ==, 0);
 460     g_assert_cmpint(bs_b->quiesce_counter, ==, 0);
 461     g_assert_cmpint(backing->quiesce_counter, ==, 0);
 462     g_assert_cmpint(a_s->drain_count, ==, 0);
 463     g_assert_cmpint(b_s->drain_count, ==, 0);
 464     g_assert_cmpint(backing_s->drain_count, ==, 0);
 465
 466     bdrv_unref(backing);
 467     bdrv_unref(bs_a);
 468     bdrv_unref(bs_b);
 469     blk_unref(blk_a);
 470     blk_unref(blk_b);
 471 }
 472
 473 static void test_graph_change_drain_subtree(void)
 474 {
 475     BlockBackend *blk_a, *blk_b;
 476     BlockDriverState *bs_a, *bs_b, *backing;
 477     BDRVTestState *a_s, *b_s, *backing_s;
 478
 479     blk_a = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 480     bs_a = bdrv_new_open_driver(&bdrv_test, "test-node-a", BDRV_O_RDWR,
 481                                 &error_abort);
 482     a_s = bs_a->opaque;
 483     blk_insert_bs(blk_a, bs_a, &error_abort);
 484
 485     blk_b = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 486     bs_b = bdrv_new_open_driver(&bdrv_test, "test-node-b", BDRV_O_RDWR,
 487                                 &error_abort);
 488     b_s = bs_b->opaque;
 489     blk_insert_bs(blk_b, bs_b, &error_abort);
 490
 491     backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort);
 492     backing_s = backing->opaque;
 493     bdrv_set_backing_hd(bs_a, backing, &error_abort);
 494
 495     g_assert_cmpint(bs_a->quiesce_counter, ==, 0);
 496     g_assert_cmpint(bs_b->quiesce_counter, ==, 0);
 497     g_assert_cmpint(backing->quiesce_counter, ==, 0);
 498     g_assert_cmpint(a_s->drain_count, ==, 0);
 499     g_assert_cmpint(b_s->drain_count, ==, 0);
 500     g_assert_cmpint(backing_s->drain_count, ==, 0);
 501
 502     do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a);
 503     do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a);
 504     do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a);
 505     do_drain_begin(BDRV_SUBTREE_DRAIN, bs_b);
 506     do_drain_begin(BDRV_SUBTREE_DRAIN, bs_b);
 507
 508     bdrv_set_backing_hd(bs_b, backing, &error_abort);
 509     g_assert_cmpint(bs_a->quiesce_counter, ==, 5);
 510     g_assert_cmpint(bs_b->quiesce_counter, ==, 5);
 511     g_assert_cmpint(backing->quiesce_counter, ==, 5);
 512     g_assert_cmpint(a_s->drain_count, ==, 5);
 513     g_assert_cmpint(b_s->drain_count, ==, 5);
 514     g_assert_cmpint(backing_s->drain_count, ==, 5);
 515
 516     bdrv_set_backing_hd(bs_b, NULL, &error_abort);
 517     g_assert_cmpint(bs_a->quiesce_counter, ==, 3);
 518     g_assert_cmpint(bs_b->quiesce_counter, ==, 2);
 519     g_assert_cmpint(backing->quiesce_counter, ==, 3);
 520     g_assert_cmpint(a_s->drain_count, ==, 3);
 521     g_assert_cmpint(b_s->drain_count, ==, 2);
 522     g_assert_cmpint(backing_s->drain_count, ==, 3);
 523
 524     bdrv_set_backing_hd(bs_b, backing, &error_abort);
 525     g_assert_cmpint(bs_a->quiesce_counter, ==, 5);
 526     g_assert_cmpint(bs_b->quiesce_counter, ==, 5);
 527     g_assert_cmpint(backing->quiesce_counter, ==, 5);
 528     g_assert_cmpint(a_s->drain_count, ==, 5);
 529     g_assert_cmpint(b_s->drain_count, ==, 5);
 530     g_assert_cmpint(backing_s->drain_count, ==, 5);
 531
 532     do_drain_end(BDRV_SUBTREE_DRAIN, bs_b);
 533     do_drain_end(BDRV_SUBTREE_DRAIN, bs_b);
 534     do_drain_end(BDRV_SUBTREE_DRAIN, bs_a);
 535     do_drain_end(BDRV_SUBTREE_DRAIN, bs_a);
 536     do_drain_end(BDRV_SUBTREE_DRAIN, bs_a);
 537
 538     g_assert_cmpint(bs_a->quiesce_counter, ==, 0);
 539     g_assert_cmpint(bs_b->quiesce_counter, ==, 0);
 540     g_assert_cmpint(backing->quiesce_counter, ==, 0);
 541     g_assert_cmpint(a_s->drain_count, ==, 0);
 542     g_assert_cmpint(b_s->drain_count, ==, 0);
 543     g_assert_cmpint(backing_s->drain_count, ==, 0);
 544
 545     bdrv_unref(backing);
 546     bdrv_unref(bs_a);
 547     bdrv_unref(bs_b);
 548     blk_unref(blk_a);
 549     blk_unref(blk_b);
 550 }
 551
 552 static void test_graph_change_drain_all(void)
 553 {
 554     BlockBackend *blk_a, *blk_b;
 555     BlockDriverState *bs_a, *bs_b;
 556     BDRVTestState *a_s, *b_s;
 557
 558     /* Create node A with a BlockBackend */
 559     blk_a = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 560     bs_a = bdrv_new_open_driver(&bdrv_test, "test-node-a", BDRV_O_RDWR,
 561                                 &error_abort);
 562     a_s = bs_a->opaque;
 563     blk_insert_bs(blk_a, bs_a, &error_abort);
 564
 565     g_assert_cmpint(bs_a->quiesce_counter, ==, 0);
 566     g_assert_cmpint(a_s->drain_count, ==, 0);
 567
 568     /* Call bdrv_drain_all_begin() */
 569     bdrv_drain_all_begin();
 570
 571     g_assert_cmpint(bs_a->quiesce_counter, ==, 1);
 572     g_assert_cmpint(a_s->drain_count, ==, 1);
 573
 574     /* Create node B with a BlockBackend */
 575     blk_b = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 576     bs_b = bdrv_new_open_driver(&bdrv_test, "test-node-b", BDRV_O_RDWR,
 577                                 &error_abort);
 578     b_s = bs_b->opaque;
 579     blk_insert_bs(blk_b, bs_b, &error_abort);
 580
 581     g_assert_cmpint(bs_a->quiesce_counter, ==, 1);
 582     g_assert_cmpint(bs_b->quiesce_counter, ==, 1);
 583     g_assert_cmpint(a_s->drain_count, ==, 1);
 584     g_assert_cmpint(b_s->drain_count, ==, 1);
 585
 586     /* Unref and finally delete node A */
 587     blk_unref(blk_a);
 588
 589     g_assert_cmpint(bs_a->quiesce_counter, ==, 1);
 590     g_assert_cmpint(bs_b->quiesce_counter, ==, 1);
 591     g_assert_cmpint(a_s->drain_count, ==, 1);
 592     g_assert_cmpint(b_s->drain_count, ==, 1);
 593
 594     bdrv_unref(bs_a);
 595
 596     g_assert_cmpint(bs_b->quiesce_counter, ==, 1);
 597     g_assert_cmpint(b_s->drain_count, ==, 1);
 598
 599     /* End the drained section */
 600     bdrv_drain_all_end();
 601
 602     g_assert_cmpint(bs_b->quiesce_counter, ==, 0);
 603     g_assert_cmpint(b_s->drain_count, ==, 0);
 604
 605     bdrv_unref(bs_b);
 606     blk_unref(blk_b);
 607 }
 608
 609 struct test_iothread_data {
 610     BlockDriverState *bs;
 611     enum drain_type drain_type;
 612     int *aio_ret;
 613 };
 614
 615 static void test_iothread_drain_entry(void *opaque)
 616 {
 617     struct test_iothread_data *data = opaque;
 618
 619     aio_context_acquire(bdrv_get_aio_context(data->bs));
 620     do_drain_begin(data->drain_type, data->bs);
 621     g_assert_cmpint(*data->aio_ret, ==, 0);
 622     do_drain_end(data->drain_type, data->bs);
 623     aio_context_release(bdrv_get_aio_context(data->bs));
 624
 625     qemu_event_set(&done_event);
 626 }
 627
 628 static void test_iothread_aio_cb(void *opaque, int ret)
 629 {
 630     int *aio_ret = opaque;
 631     *aio_ret = ret;
 632     qemu_event_set(&done_event);
 633 }
 634
 635 static void test_iothread_main_thread_bh(void *opaque)
 636 {
 637     struct test_iothread_data *data = opaque;
 638
 639     /* Test that the AioContext is not yet locked in a random BH that is
 640      * executed during drain, otherwise this would deadlock. */
 641     aio_context_acquire(bdrv_get_aio_context(data->bs));
 642     bdrv_flush(data->bs);
 643     aio_context_release(bdrv_get_aio_context(data->bs));
 644 }
 645
 646 /*
 647  * Starts an AIO request on a BDS that runs in the AioContext of iothread 1.
 648  * The request involves a BH on iothread 2 before it can complete.
 649  *
 650  * @drain_thread = 0 means that do_drain_begin/end are called from the main
 651  * thread, @drain_thread = 1 means that they are called from iothread 1. Drain
 652  * for this BDS cannot be called from iothread 2 because only the main thread
 653  * may do cross-AioContext polling.
 654  */
 655 static void test_iothread_common(enum drain_type drain_type, int drain_thread)
 656 {
 657     BlockBackend *blk;
 658     BlockDriverState *bs;
 659     BDRVTestState *s;
 660     BlockAIOCB *acb;
 661     int aio_ret;
 662     struct test_iothread_data data;
 663
 664     IOThread *a = iothread_new();
 665     IOThread *b = iothread_new();
 666     AioContext *ctx_a = iothread_get_aio_context(a);
 667     AioContext *ctx_b = iothread_get_aio_context(b);
 668
 669     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, 0);
 670
 671     /* bdrv_drain_all() may only be called from the main loop thread */
 672     if (drain_type == BDRV_DRAIN_ALL && drain_thread != 0) {
 673         goto out;
 674     }
 675
 676     blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 677     bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR,
 678                               &error_abort);
 679     s = bs->opaque;
 680     blk_insert_bs(blk, bs, &error_abort);
 681
 682     blk_set_aio_context(blk, ctx_a, &error_abort);
 683     aio_context_acquire(ctx_a);
 684
 685     s->bh_indirection_ctx = ctx_b;
 686
 687     aio_ret = -EINPROGRESS;
 688     qemu_event_reset(&done_event);
 689
 690     if (drain_thread == 0) {
 691         acb = blk_aio_preadv(blk, 0, &qiov, 0, test_iothread_aio_cb, &aio_ret);
 692     } else {
 693         acb = blk_aio_preadv(blk, 0, &qiov, 0, aio_ret_cb, &aio_ret);
 694     }
 695     g_assert(acb != NULL);
 696     g_assert_cmpint(aio_ret, ==, -EINPROGRESS);
 697
 698     aio_context_release(ctx_a);
 699
 700     data = (struct test_iothread_data) {
 701         .bs         = bs,
 702         .drain_type = drain_type,
 703         .aio_ret    = &aio_ret,
 704     };
 705
 706     switch (drain_thread) {
 707     case 0:
 708         if (drain_type != BDRV_DRAIN_ALL) {
 709             aio_context_acquire(ctx_a);
 710         }
 711
 712         aio_bh_schedule_oneshot(ctx_a, test_iothread_main_thread_bh, &data);
 713
 714         /* The request is running on the IOThread a. Draining its block device
 715          * will make sure that it has completed as far as the BDS is concerned,
 716          * but the drain in this thread can continue immediately after
 717          * bdrv_dec_in_flight() and aio_ret might be assigned only slightly
 718          * later. */
 719         do_drain_begin(drain_type, bs);
 720         g_assert_cmpint(bs->in_flight, ==, 0);
 721
 722         if (drain_type != BDRV_DRAIN_ALL) {
 723             aio_context_release(ctx_a);
 724         }
 725         qemu_event_wait(&done_event);
 726         if (drain_type != BDRV_DRAIN_ALL) {
 727             aio_context_acquire(ctx_a);
 728         }
 729
 730         g_assert_cmpint(aio_ret, ==, 0);
 731         do_drain_end(drain_type, bs);
 732
 733         if (drain_type != BDRV_DRAIN_ALL) {
 734             aio_context_release(ctx_a);
 735         }
 736         break;
 737     case 1:
 738         aio_bh_schedule_oneshot(ctx_a, test_iothread_drain_entry, &data);
 739         qemu_event_wait(&done_event);
 740         break;
 741     default:
 742         g_assert_not_reached();
 743     }
 744
 745     aio_context_acquire(ctx_a);
 746     blk_set_aio_context(blk, qemu_get_aio_context(), &error_abort);
 747     aio_context_release(ctx_a);
 748
 749     bdrv_unref(bs);
 750     blk_unref(blk);
 751
 752 out:
 753     iothread_join(a);
 754     iothread_join(b);
 755 }
 756
 757 static void test_iothread_drain_all(void)
 758 {
 759     test_iothread_common(BDRV_DRAIN_ALL, 0);
 760     test_iothread_common(BDRV_DRAIN_ALL, 1);
 761 }
 762
 763 static void test_iothread_drain(void)
 764 {
 765     test_iothread_common(BDRV_DRAIN, 0);
 766     test_iothread_common(BDRV_DRAIN, 1);
 767 }
 768
 769 static void test_iothread_drain_subtree(void)
 770 {
 771     test_iothread_common(BDRV_SUBTREE_DRAIN, 0);
 772     test_iothread_common(BDRV_SUBTREE_DRAIN, 1);
 773 }
 774
 775
 776 typedef struct TestBlockJob {
 777     BlockJob common;
 778     int run_ret;
 779     int prepare_ret;
 780     bool running;
 781     bool should_complete;
 782 } TestBlockJob;
 783
 784 static int test_job_prepare(Job *job)
 785 {
 786     TestBlockJob *s = container_of(job, TestBlockJob, common.job);
 787
 788     /* Provoke an AIO_WAIT_WHILE() call to verify there is no deadlock */
 789     blk_flush(s->common.blk);
 790     return s->prepare_ret;
 791 }
 792
 793 static void test_job_commit(Job *job)
 794 {
 795     TestBlockJob *s = container_of(job, TestBlockJob, common.job);
 796
 797     /* Provoke an AIO_WAIT_WHILE() call to verify there is no deadlock */
 798     blk_flush(s->common.blk);
 799 }
 800
 801 static void test_job_abort(Job *job)
 802 {
 803     TestBlockJob *s = container_of(job, TestBlockJob, common.job);
 804
 805     /* Provoke an AIO_WAIT_WHILE() call to verify there is no deadlock */
 806     blk_flush(s->common.blk);
 807 }
 808
 809 static int coroutine_fn test_job_run(Job *job, Error **errp)
 810 {
 811     TestBlockJob *s = container_of(job, TestBlockJob, common.job);
 812
 813     /* We are running the actual job code past the pause point in
 814      * job_co_entry(). */
 815     s->running = true;
 816
 817     job_transition_to_ready(&s->common.job);
 818     while (!s->should_complete) {
 819         /* Avoid job_sleep_ns() because it marks the job as !busy. We want to
 820          * emulate some actual activity (probably some I/O) here so that drain
 821          * has to wait for this activity to stop. */
 822         qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 1000000);
 823
 824         job_pause_point(&s->common.job);
 825     }
 826
 827     return s->run_ret;
 828 }
 829
 830 static void test_job_complete(Job *job, Error **errp)
 831 {
 832     TestBlockJob *s = container_of(job, TestBlockJob, common.job);
 833     s->should_complete = true;
 834 }
 835
 836 BlockJobDriver test_job_driver = {
 837     .job_driver = {
 838         .instance_size  = sizeof(TestBlockJob),
 839         .free           = block_job_free,
 840         .user_resume    = block_job_user_resume,
 841         .drain          = block_job_drain,
 842         .run            = test_job_run,
 843         .complete       = test_job_complete,
 844         .prepare        = test_job_prepare,
 845         .commit         = test_job_commit,
 846         .abort          = test_job_abort,
 847     },
 848 };
 849
 850 enum test_job_result {
 851     TEST_JOB_SUCCESS,
 852     TEST_JOB_FAIL_RUN,
 853     TEST_JOB_FAIL_PREPARE,
 854 };
 855
 856 enum test_job_drain_node {
 857     TEST_JOB_DRAIN_SRC,
 858     TEST_JOB_DRAIN_SRC_CHILD,
 859     TEST_JOB_DRAIN_SRC_PARENT,
 860 };
 861
 862 static void test_blockjob_common_drain_node(enum drain_type drain_type,
 863                                             bool use_iothread,
 864                                             enum test_job_result result,
 865                                             enum test_job_drain_node drain_node)
 866 {
 867     BlockBackend *blk_src, *blk_target;
 868     BlockDriverState *src, *src_backing, *src_overlay, *target, *drain_bs;
 869     BlockJob *job;
 870     TestBlockJob *tjob;
 871     IOThread *iothread = NULL;
 872     AioContext *ctx;
 873     int ret;
 874
 875     src = bdrv_new_open_driver(&bdrv_test, "source", BDRV_O_RDWR,
 876                                &error_abort);
 877     src_backing = bdrv_new_open_driver(&bdrv_test, "source-backing",
 878                                        BDRV_O_RDWR, &error_abort);
 879     src_overlay = bdrv_new_open_driver(&bdrv_test, "source-overlay",
 880                                        BDRV_O_RDWR, &error_abort);
 881
 882     bdrv_set_backing_hd(src_overlay, src, &error_abort);
 883     bdrv_unref(src);
 884     bdrv_set_backing_hd(src, src_backing, &error_abort);
 885     bdrv_unref(src_backing);
 886
 887     blk_src = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 888     blk_insert_bs(blk_src, src_overlay, &error_abort);
 889
 890     switch (drain_node) {
 891     case TEST_JOB_DRAIN_SRC:
 892         drain_bs = src;
 893         break;
 894     case TEST_JOB_DRAIN_SRC_CHILD:
 895         drain_bs = src_backing;
 896         break;
 897     case TEST_JOB_DRAIN_SRC_PARENT:
 898         drain_bs = src_overlay;
 899         break;
 900     default:
 901         g_assert_not_reached();
 902     }
 903
 904     if (use_iothread) {
 905         iothread = iothread_new();
 906         ctx = iothread_get_aio_context(iothread);
 907         blk_set_aio_context(blk_src, ctx, &error_abort);
 908     } else {
 909         ctx = qemu_get_aio_context();
 910     }
 911
 912     target = bdrv_new_open_driver(&bdrv_test, "target", BDRV_O_RDWR,
 913                                   &error_abort);
 914     blk_target = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
 915     blk_insert_bs(blk_target, target, &error_abort);
 916     blk_set_allow_aio_context_change(blk_target, true);
 917
 918     aio_context_acquire(ctx);
 919     tjob = block_job_create("job0", &test_job_driver, NULL, src,
 920                             0, BLK_PERM_ALL,
 921                             0, 0, NULL, NULL, &error_abort);
 922     job = &tjob->common;
 923     block_job_add_bdrv(job, "target", target, 0, BLK_PERM_ALL, &error_abort);
 924
 925     switch (result) {
 926     case TEST_JOB_SUCCESS:
 927         break;
 928     case TEST_JOB_FAIL_RUN:
 929         tjob->run_ret = -EIO;
 930         break;
 931     case TEST_JOB_FAIL_PREPARE:
 932         tjob->prepare_ret = -EIO;
 933         break;
 934     }
 935
 936     job_start(&job->job);
 937     aio_context_release(ctx);
 938
 939     if (use_iothread) {
 940         /* job_co_entry() is run in the I/O thread, wait for the actual job
 941          * code to start (we don't want to catch the job in the pause point in
 942          * job_co_entry(). */
 943         while (!tjob->running) {
 944             aio_poll(qemu_get_aio_context(), false);
 945         }
 946     }
 947
 948     g_assert_cmpint(job->job.pause_count, ==, 0);
 949     g_assert_false(job->job.paused);
 950     g_assert_true(tjob->running);
 951     g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
 952
 953     do_drain_begin_unlocked(drain_type, drain_bs);
 954
 955     if (drain_type == BDRV_DRAIN_ALL) {
 956         /* bdrv_drain_all() drains both src and target */
 957         g_assert_cmpint(job->job.pause_count, ==, 2);
 958     } else {
 959         g_assert_cmpint(job->job.pause_count, ==, 1);
 960     }
 961     g_assert_true(job->job.paused);
 962     g_assert_false(job->job.busy); /* The job is paused */
 963
 964     do_drain_end_unlocked(drain_type, drain_bs);
 965
 966     if (use_iothread) {
 967         /* paused is reset in the I/O thread, wait for it */
 968         while (job->job.paused) {
 969             aio_poll(qemu_get_aio_context(), false);
 970         }
 971     }
 972
 973     g_assert_cmpint(job->job.pause_count, ==, 0);
 974     g_assert_false(job->job.paused);
 975     g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
 976
 977     do_drain_begin_unlocked(drain_type, target);
 978
 979     if (drain_type == BDRV_DRAIN_ALL) {
 980         /* bdrv_drain_all() drains both src and target */
 981         g_assert_cmpint(job->job.pause_count, ==, 2);
 982     } else {
 983         g_assert_cmpint(job->job.pause_count, ==, 1);
 984     }
 985     g_assert_true(job->job.paused);
 986     g_assert_false(job->job.busy); /* The job is paused */
 987
 988     do_drain_end_unlocked(drain_type, target);
 989
 990     if (use_iothread) {
 991         /* paused is reset in the I/O thread, wait for it */
 992         while (job->job.paused) {
 993             aio_poll(qemu_get_aio_context(), false);
 994         }
 995     }
 996
 997     g_assert_cmpint(job->job.pause_count, ==, 0);
 998     g_assert_false(job->job.paused);
 999     g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */
1000
1001     aio_context_acquire(ctx);
1002     ret = job_complete_sync(&job->job, &error_abort);
1003     g_assert_cmpint(ret, ==, (result == TEST_JOB_SUCCESS ? 0 : -EIO));
1004
1005     if (use_iothread) {
1006         blk_set_aio_context(blk_src, qemu_get_aio_context(), &error_abort);
1007         assert(blk_get_aio_context(blk_target) == qemu_get_aio_context());
1008     }
1009     aio_context_release(ctx);
1010
1011     blk_unref(blk_src);
1012     blk_unref(blk_target);
1013     bdrv_unref(src_overlay);
1014     bdrv_unref(target);
1015
1016     if (iothread) {
1017         iothread_join(iothread);
1018     }
1019 }
1020
1021 static void test_blockjob_common(enum drain_type drain_type, bool use_iothread,
1022                                  enum test_job_result result)
1023 {
1024     test_blockjob_common_drain_node(drain_type, use_iothread, result,
1025                                     TEST_JOB_DRAIN_SRC);
1026     test_blockjob_common_drain_node(drain_type, use_iothread, result,
1027                                     TEST_JOB_DRAIN_SRC_CHILD);
1028     if (drain_type == BDRV_SUBTREE_DRAIN) {
1029         test_blockjob_common_drain_node(drain_type, use_iothread, result,
1030                                         TEST_JOB_DRAIN_SRC_PARENT);
1031     }
1032 }
1033
1034 static void test_blockjob_drain_all(void)
1035 {
1036     test_blockjob_common(BDRV_DRAIN_ALL, false, TEST_JOB_SUCCESS);
1037 }
1038
1039 static void test_blockjob_drain(void)
1040 {
1041     test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_SUCCESS);
1042 }
1043
1044 static void test_blockjob_drain_subtree(void)
1045 {
1046     test_blockjob_common(BDRV_SUBTREE_DRAIN, false, TEST_JOB_SUCCESS);
1047 }
1048
1049 static void test_blockjob_error_drain_all(void)
1050 {
1051     test_blockjob_common(BDRV_DRAIN_ALL, false, TEST_JOB_FAIL_RUN);
1052     test_blockjob_common(BDRV_DRAIN_ALL, false, TEST_JOB_FAIL_PREPARE);
1053 }
1054
1055 static void test_blockjob_error_drain(void)
1056 {
1057     test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_FAIL_RUN);
1058     test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_FAIL_PREPARE);
1059 }
1060
1061 static void test_blockjob_error_drain_subtree(void)
1062 {
1063     test_blockjob_common(BDRV_SUBTREE_DRAIN, false, TEST_JOB_FAIL_RUN);
1064     test_blockjob_common(BDRV_SUBTREE_DRAIN, false, TEST_JOB_FAIL_PREPARE);
1065 }
1066
1067 static void test_blockjob_iothread_drain_all(void)
1068 {
1069     test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_SUCCESS);
1070 }
1071
1072 static void test_blockjob_iothread_drain(void)
1073 {
1074     test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_SUCCESS);
1075 }
1076
1077 static void test_blockjob_iothread_drain_subtree(void)
1078 {
1079     test_blockjob_common(BDRV_SUBTREE_DRAIN, true, TEST_JOB_SUCCESS);
1080 }
1081
1082 static void test_blockjob_iothread_error_drain_all(void)
1083 {
1084     test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_FAIL_RUN);
1085     test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_FAIL_PREPARE);
1086 }
1087
1088 static void test_blockjob_iothread_error_drain(void)
1089 {
1090     test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_FAIL_RUN);
1091     test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_FAIL_PREPARE);
1092 }
1093
1094 static void test_blockjob_iothread_error_drain_subtree(void)
1095 {
1096     test_blockjob_common(BDRV_SUBTREE_DRAIN, true, TEST_JOB_FAIL_RUN);
1097     test_blockjob_common(BDRV_SUBTREE_DRAIN, true, TEST_JOB_FAIL_PREPARE);
1098 }
1099
1100
1101 typedef struct BDRVTestTopState {
1102     BdrvChild *wait_child;
1103 } BDRVTestTopState;
1104
1105 static void bdrv_test_top_close(BlockDriverState *bs)
1106 {
1107     BdrvChild *c, *next_c;
1108     QLIST_FOREACH_SAFE(c, &bs->children, next, next_c) {
1109         bdrv_unref_child(bs, c);
1110     }
1111 }
1112
1113 static int coroutine_fn bdrv_test_top_co_preadv(BlockDriverState *bs,
1114                                                 uint64_t offset, uint64_t bytes,
1115                                                 QEMUIOVector *qiov, int flags)
1116 {
1117     BDRVTestTopState *tts = bs->opaque;
1118     return bdrv_co_preadv(tts->wait_child, offset, bytes, qiov, flags);
1119 }
1120
1121 static BlockDriver bdrv_test_top_driver = {
1122     .format_name            = "test_top_driver",
1123     .instance_size          = sizeof(BDRVTestTopState),
1124
1125     .bdrv_close             = bdrv_test_top_close,
1126     .bdrv_co_preadv         = bdrv_test_top_co_preadv,
1127
1128     .bdrv_child_perm        = bdrv_format_default_perms,
1129 };
1130
1131 typedef struct TestCoDeleteByDrainData {
1132     BlockBackend *blk;
1133     bool detach_instead_of_delete;
1134     bool done;
1135 } TestCoDeleteByDrainData;
1136
1137 static void coroutine_fn test_co_delete_by_drain(void *opaque)
1138 {
1139     TestCoDeleteByDrainData *dbdd = opaque;
1140     BlockBackend *blk = dbdd->blk;
1141     BlockDriverState *bs = blk_bs(blk);
1142     BDRVTestTopState *tts = bs->opaque;
1143     void *buffer = g_malloc(65536);
1144     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buffer, 65536);
1145
1146     /* Pretend some internal write operation from parent to child.
1147      * Important: We have to read from the child, not from the parent!
1148      * Draining works by first propagating it all up the tree to the
1149      * root and then waiting for drainage from root to the leaves
1150      * (protocol nodes).  If we have a request waiting on the root,
1151      * everything will be drained before we go back down the tree, but
1152      * we do not want that.  We want to be in the middle of draining
1153      * when this following requests returns. */
1154     bdrv_co_preadv(tts->wait_child, 0, 65536, &qiov, 0);
1155
1156     g_assert_cmpint(bs->refcnt, ==, 1);
1157
1158     if (!dbdd->detach_instead_of_delete) {
1159         blk_unref(blk);
1160     } else {
1161         BdrvChild *c, *next_c;
1162         QLIST_FOREACH_SAFE(c, &bs->children, next, next_c) {
1163             bdrv_unref_child(bs, c);
1164         }
1165     }
1166
1167     dbdd->done = true;
1168     g_free(buffer);
1169 }
1170
1171 /**
1172  * Test what happens when some BDS has some children, you drain one of
1173  * them and this results in the BDS being deleted.
1174  *
1175  * If @detach_instead_of_delete is set, the BDS is not going to be
1176  * deleted but will only detach all of its children.
1177  */
1178 static void do_test_delete_by_drain(bool detach_instead_of_delete,
1179                                     enum drain_type drain_type)
1180 {
1181     BlockBackend *blk;
1182     BlockDriverState *bs, *child_bs, *null_bs;
1183     BDRVTestTopState *tts;
1184     TestCoDeleteByDrainData dbdd;
1185     Coroutine *co;
1186
1187     bs = bdrv_new_open_driver(&bdrv_test_top_driver, "top", BDRV_O_RDWR,
1188                               &error_abort);
1189     bs->total_sectors = 65536 >> BDRV_SECTOR_BITS;
1190     tts = bs->opaque;
1191
1192     null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL,
1193                         &error_abort);
1194     bdrv_attach_child(bs, null_bs, "null-child", &child_file, &error_abort);
1195
1196     /* This child will be the one to pass to requests through to, and
1197      * it will stall until a drain occurs */
1198     child_bs = bdrv_new_open_driver(&bdrv_test, "child", BDRV_O_RDWR,
1199                                     &error_abort);
1200     child_bs->total_sectors = 65536 >> BDRV_SECTOR_BITS;
1201     /* Takes our reference to child_bs */
1202     tts->wait_child = bdrv_attach_child(bs, child_bs, "wait-child", &child_file,
1203                                         &error_abort);
1204
1205     /* This child is just there to be deleted
1206      * (for detach_instead_of_delete == true) */
1207     null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL,
1208                         &error_abort);
1209     bdrv_attach_child(bs, null_bs, "null-child", &child_file, &error_abort);
1210
1211     blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
1212     blk_insert_bs(blk, bs, &error_abort);
1213
1214     /* Referenced by blk now */
1215     bdrv_unref(bs);
1216
1217     g_assert_cmpint(bs->refcnt, ==, 1);
1218     g_assert_cmpint(child_bs->refcnt, ==, 1);
1219     g_assert_cmpint(null_bs->refcnt, ==, 1);
1220
1221
1222     dbdd = (TestCoDeleteByDrainData){
1223         .blk = blk,
1224         .detach_instead_of_delete = detach_instead_of_delete,
1225         .done = false,
1226     };
1227     co = qemu_coroutine_create(test_co_delete_by_drain, &dbdd);
1228     qemu_coroutine_enter(co);
1229
1230     /* Drain the child while the read operation is still pending.
1231      * This should result in the operation finishing and
1232      * test_co_delete_by_drain() resuming.  Thus, @bs will be deleted
1233      * and the coroutine will exit while this drain operation is still
1234      * in progress. */
1235     switch (drain_type) {
1236     case BDRV_DRAIN:
1237         bdrv_ref(child_bs);
1238         bdrv_drain(child_bs);
1239         bdrv_unref(child_bs);
1240         break;
1241     case BDRV_SUBTREE_DRAIN:
1242         /* Would have to ref/unref bs here for !detach_instead_of_delete, but
1243          * then the whole test becomes pointless because the graph changes
1244          * don't occur during the drain any more. */
1245         assert(detach_instead_of_delete);
1246         bdrv_subtree_drained_begin(bs);
1247         bdrv_subtree_drained_end(bs);
1248         break;
1249     case BDRV_DRAIN_ALL:
1250         bdrv_drain_all_begin();
1251         bdrv_drain_all_end();
1252         break;
1253     default:
1254         g_assert_not_reached();
1255     }
1256
1257     while (!dbdd.done) {
1258         aio_poll(qemu_get_aio_context(), true);
1259     }
1260
1261     if (detach_instead_of_delete) {
1262         /* Here, the reference has not passed over to the coroutine,
1263          * so we have to delete the BB ourselves */
1264         blk_unref(blk);
1265     }
1266 }
1267
1268 static void test_delete_by_drain(void)
1269 {
1270     do_test_delete_by_drain(false, BDRV_DRAIN);
1271 }
1272
1273 static void test_detach_by_drain_all(void)
1274 {
1275     do_test_delete_by_drain(true, BDRV_DRAIN_ALL);
1276 }
1277
1278 static void test_detach_by_drain(void)
1279 {
1280     do_test_delete_by_drain(true, BDRV_DRAIN);
1281 }
1282
1283 static void test_detach_by_drain_subtree(void)
1284 {
1285     do_test_delete_by_drain(true, BDRV_SUBTREE_DRAIN);
1286 }
1287
1288
1289 struct detach_by_parent_data {
1290     BlockDriverState *parent_b;
1291     BdrvChild *child_b;
1292     BlockDriverState *c;
1293     BdrvChild *child_c;
1294     bool by_parent_cb;
1295 };
1296 static struct detach_by_parent_data detach_by_parent_data;
1297
1298 static void detach_indirect_bh(void *opaque)
1299 {
1300     struct detach_by_parent_data *data = opaque;
1301
1302     bdrv_unref_child(data->parent_b, data->child_b);
1303
1304     bdrv_ref(data->c);
1305     data->child_c = bdrv_attach_child(data->parent_b, data->c, "PB-C",
1306                                       &child_file, &error_abort);
1307 }
1308
1309 static void detach_by_parent_aio_cb(void *opaque, int ret)
1310 {
1311     struct detach_by_parent_data *data = &detach_by_parent_data;
1312
1313     g_assert_cmpint(ret, ==, 0);
1314     if (data->by_parent_cb) {
1315         detach_indirect_bh(data);
1316     }
1317 }
1318
1319 static void detach_by_driver_cb_drained_begin(BdrvChild *child)
1320 {
1321     aio_bh_schedule_oneshot(qemu_get_current_aio_context(),
1322                             detach_indirect_bh, &detach_by_parent_data);
1323     child_file.drained_begin(child);
1324 }
1325
1326 static BdrvChildRole detach_by_driver_cb_role;
1327
1328 /*
1329  * Initial graph:
1330  *
1331  * PA     PB
1332  *    \ /   \
1333  *     A     B     C
1334  *
1335  * by_parent_cb == true:  Test that parent callbacks don't poll
1336  *
1337  *     PA has a pending write request whose callback changes the child nodes of
1338  *     PB: It removes B and adds C instead. The subtree of PB is drained, which
1339  *     will indirectly drain the write request, too.
1340  *
1341  * by_parent_cb == false: Test that bdrv_drain_invoke() doesn't poll
1342  *
1343  *     PA's BdrvChildRole has a .drained_begin callback that schedules a BH
1344  *     that does the same graph change. If bdrv_drain_invoke() calls it, the
1345  *     state is messed up, but if it is only polled in the single
1346  *     BDRV_POLL_WHILE() at the end of the drain, this should work fine.
1347  */
1348 static void test_detach_indirect(bool by_parent_cb)
1349 {
1350     BlockBackend *blk;
1351     BlockDriverState *parent_a, *parent_b, *a, *b, *c;
1352     BdrvChild *child_a, *child_b;
1353     BlockAIOCB *acb;
1354
1355     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, 0);
1356
1357     if (!by_parent_cb) {
1358         detach_by_driver_cb_role = child_file;
1359         detach_by_driver_cb_role.drained_begin =
1360             detach_by_driver_cb_drained_begin;
1361     }
1362
1363     /* Create all involved nodes */
1364     parent_a = bdrv_new_open_driver(&bdrv_test, "parent-a", BDRV_O_RDWR,
1365                                     &error_abort);
1366     parent_b = bdrv_new_open_driver(&bdrv_test, "parent-b", 0,
1367                                     &error_abort);
1368
1369     a = bdrv_new_open_driver(&bdrv_test, "a", BDRV_O_RDWR, &error_abort);
1370     b = bdrv_new_open_driver(&bdrv_test, "b", BDRV_O_RDWR, &error_abort);
1371     c = bdrv_new_open_driver(&bdrv_test, "c", BDRV_O_RDWR, &error_abort);
1372
1373     /* blk is a BB for parent-a */
1374     blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
1375     blk_insert_bs(blk, parent_a, &error_abort);
1376     bdrv_unref(parent_a);
1377
1378     /* If we want to get bdrv_drain_invoke() to call aio_poll(), the driver
1379      * callback must not return immediately. */
1380     if (!by_parent_cb) {
1381         BDRVTestState *s = parent_a->opaque;
1382         s->sleep_in_drain_begin = true;
1383     }
1384
1385     /* Set child relationships */
1386     bdrv_ref(b);
1387     bdrv_ref(a);
1388     child_b = bdrv_attach_child(parent_b, b, "PB-B", &child_file, &error_abort);
1389     child_a = bdrv_attach_child(parent_b, a, "PB-A", &child_backing, &error_abort);
1390
1391     bdrv_ref(a);
1392     bdrv_attach_child(parent_a, a, "PA-A",
1393                       by_parent_cb ? &child_file : &detach_by_driver_cb_role,
1394                       &error_abort);
1395
1396     g_assert_cmpint(parent_a->refcnt, ==, 1);
1397     g_assert_cmpint(parent_b->refcnt, ==, 1);
1398     g_assert_cmpint(a->refcnt, ==, 3);
1399     g_assert_cmpint(b->refcnt, ==, 2);
1400     g_assert_cmpint(c->refcnt, ==, 1);
1401
1402     g_assert(QLIST_FIRST(&parent_b->children) == child_a);
1403     g_assert(QLIST_NEXT(child_a, next) == child_b);
1404     g_assert(QLIST_NEXT(child_b, next) == NULL);
1405
1406     /* Start the evil write request */
1407     detach_by_parent_data = (struct detach_by_parent_data) {
1408         .parent_b = parent_b,
1409         .child_b = child_b,
1410         .c = c,
1411         .by_parent_cb = by_parent_cb,
1412     };
1413     acb = blk_aio_preadv(blk, 0, &qiov, 0, detach_by_parent_aio_cb, NULL);
1414     g_assert(acb != NULL);
1415
1416     /* Drain and check the expected result */
1417     bdrv_subtree_drained_begin(parent_b);
1418
1419     g_assert(detach_by_parent_data.child_c != NULL);
1420
1421     g_assert_cmpint(parent_a->refcnt, ==, 1);
1422     g_assert_cmpint(parent_b->refcnt, ==, 1);
1423     g_assert_cmpint(a->refcnt, ==, 3);
1424     g_assert_cmpint(b->refcnt, ==, 1);
1425     g_assert_cmpint(c->refcnt, ==, 2);
1426
1427     g_assert(QLIST_FIRST(&parent_b->children) == detach_by_parent_data.child_c);
1428     g_assert(QLIST_NEXT(detach_by_parent_data.child_c, next) == child_a);
1429     g_assert(QLIST_NEXT(child_a, next) == NULL);
1430
1431     g_assert_cmpint(parent_a->quiesce_counter, ==, 1);
1432     g_assert_cmpint(parent_b->quiesce_counter, ==, 1);
1433     g_assert_cmpint(a->quiesce_counter, ==, 1);
1434     g_assert_cmpint(b->quiesce_counter, ==, 0);
1435     g_assert_cmpint(c->quiesce_counter, ==, 1);
1436
1437     bdrv_subtree_drained_end(parent_b);
1438
1439     bdrv_unref(parent_b);
1440     blk_unref(blk);
1441
1442     g_assert_cmpint(a->refcnt, ==, 1);
1443     g_assert_cmpint(b->refcnt, ==, 1);
1444     g_assert_cmpint(c->refcnt, ==, 1);
1445     bdrv_unref(a);
1446     bdrv_unref(b);
1447     bdrv_unref(c);
1448 }
1449
1450 static void test_detach_by_parent_cb(void)
1451 {
1452     test_detach_indirect(true);
1453 }
1454
1455 static void test_detach_by_driver_cb(void)
1456 {
1457     test_detach_indirect(false);
1458 }
1459
1460 static void test_append_to_drained(void)
1461 {
1462     BlockBackend *blk;
1463     BlockDriverState *base, *overlay;
1464     BDRVTestState *base_s, *overlay_s;
1465
1466     blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
1467     base = bdrv_new_open_driver(&bdrv_test, "base", BDRV_O_RDWR, &error_abort);
1468     base_s = base->opaque;
1469     blk_insert_bs(blk, base, &error_abort);
1470
1471     overlay = bdrv_new_open_driver(&bdrv_test, "overlay", BDRV_O_RDWR,
1472                                    &error_abort);
1473     overlay_s = overlay->opaque;
1474
1475     do_drain_begin(BDRV_DRAIN, base);
1476     g_assert_cmpint(base->quiesce_counter, ==, 1);
1477     g_assert_cmpint(base_s->drain_count, ==, 1);
1478     g_assert_cmpint(base->in_flight, ==, 0);
1479
1480     /* Takes ownership of overlay, so we don't have to unref it later */
1481     bdrv_append(overlay, base, &error_abort);
1482     g_assert_cmpint(base->in_flight, ==, 0);
1483     g_assert_cmpint(overlay->in_flight, ==, 0);
1484
1485     g_assert_cmpint(base->quiesce_counter, ==, 1);
1486     g_assert_cmpint(base_s->drain_count, ==, 1);
1487     g_assert_cmpint(overlay->quiesce_counter, ==, 1);
1488     g_assert_cmpint(overlay_s->drain_count, ==, 1);
1489
1490     do_drain_end(BDRV_DRAIN, base);
1491
1492     g_assert_cmpint(base->quiesce_counter, ==, 0);
1493     g_assert_cmpint(base_s->drain_count, ==, 0);
1494     g_assert_cmpint(overlay->quiesce_counter, ==, 0);
1495     g_assert_cmpint(overlay_s->drain_count, ==, 0);
1496
1497     bdrv_unref(base);
1498     blk_unref(blk);
1499 }
1500
1501 static void test_set_aio_context(void)
1502 {
1503     BlockDriverState *bs;
1504     IOThread *a = iothread_new();
1505     IOThread *b = iothread_new();
1506     AioContext *ctx_a = iothread_get_aio_context(a);
1507     AioContext *ctx_b = iothread_get_aio_context(b);
1508
1509     bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR,
1510                               &error_abort);
1511
1512     bdrv_drained_begin(bs);
1513     bdrv_try_set_aio_context(bs, ctx_a, &error_abort);
1514
1515     aio_context_acquire(ctx_a);
1516     bdrv_drained_end(bs);
1517
1518     bdrv_drained_begin(bs);
1519     bdrv_try_set_aio_context(bs, ctx_b, &error_abort);
1520     aio_context_release(ctx_a);
1521     aio_context_acquire(ctx_b);
1522     bdrv_try_set_aio_context(bs, qemu_get_aio_context(), &error_abort);
1523     aio_context_release(ctx_b);
1524     bdrv_drained_end(bs);
1525
1526     bdrv_unref(bs);
1527     iothread_join(a);
1528     iothread_join(b);
1529 }
1530
1531
1532 typedef struct TestDropBackingBlockJob {
1533     BlockJob common;
1534     bool should_complete;
1535     bool *did_complete;
1536     BlockDriverState *detach_also;
1537 } TestDropBackingBlockJob;
1538
1539 static int coroutine_fn test_drop_backing_job_run(Job *job, Error **errp)
1540 {
1541     TestDropBackingBlockJob *s =
1542         container_of(job, TestDropBackingBlockJob, common.job);
1543
1544     while (!s->should_complete) {
1545         job_sleep_ns(job, 0);
1546     }
1547
1548     return 0;
1549 }
1550
1551 static void test_drop_backing_job_commit(Job *job)
1552 {
1553     TestDropBackingBlockJob *s =
1554         container_of(job, TestDropBackingBlockJob, common.job);
1555
1556     bdrv_set_backing_hd(blk_bs(s->common.blk), NULL, &error_abort);
1557     bdrv_set_backing_hd(s->detach_also, NULL, &error_abort);
1558
1559     *s->did_complete = true;
1560 }
1561
1562 static const BlockJobDriver test_drop_backing_job_driver = {
1563     .job_driver = {
1564         .instance_size  = sizeof(TestDropBackingBlockJob),
1565         .free           = block_job_free,
1566         .user_resume    = block_job_user_resume,
1567         .drain          = block_job_drain,
1568         .run            = test_drop_backing_job_run,
1569         .commit         = test_drop_backing_job_commit,
1570     }
1571 };
1572
1573 /**
1574  * Creates a child node with three parent nodes on it, and then runs a
1575  * block job on the final one, parent-node-2.
1576  *
1577  * The job is then asked to complete before a section where the child
1578  * is drained.
1579  *
1580  * Ending this section will undrain the child's parents, first
1581  * parent-node-2, then parent-node-1, then parent-node-0 -- the parent
1582  * list is in reverse order of how they were added.  Ending the drain
1583  * on parent-node-2 will resume the job, thus completing it and
1584  * scheduling job_exit().
1585  *
1586  * Ending the drain on parent-node-1 will poll the AioContext, which
1587  * lets job_exit() and thus test_drop_backing_job_commit() run.  That
1588  * function first removes the child as parent-node-2's backing file.
1589  *
1590  * In old (and buggy) implementations, there are two problems with
1591  * that:
1592  * (A) bdrv_drain_invoke() polls for every node that leaves the
1593  *     drained section.  This means that job_exit() is scheduled
1594  *     before the child has left the drained section.  Its
1595  *     quiesce_counter is therefore still 1 when it is removed from
1596  *     parent-node-2.
1597  *
1598  * (B) bdrv_replace_child_noperm() calls drained_end() on the old
1599  *     child's parents as many times as the child is quiesced.  This
1600  *     means it will call drained_end() on parent-node-2 once.
1601  *     Because parent-node-2 is no longer quiesced at this point, this
1602  *     will fail.
1603  *
1604  * bdrv_replace_child_noperm() therefore must call drained_end() on
1605  * the parent only if it really is still drained because the child is
1606  * drained.
1607  *
1608  * If removing child from parent-node-2 was successful (as it should
1609  * be), test_drop_backing_job_commit() will then also remove the child
1610  * from parent-node-0.
1611  *
1612  * With an old version of our drain infrastructure ((A) above), that
1613  * resulted in the following flow:
1614  *
1615  * 1. child attempts to leave its drained section.  The call recurses
1616  *    to its parents.
1617  *
1618  * 2. parent-node-2 leaves the drained section.  Polling in
1619  *    bdrv_drain_invoke() will schedule job_exit().
1620  *
1621  * 3. parent-node-1 leaves the drained section.  Polling in
1622  *    bdrv_drain_invoke() will run job_exit(), thus disconnecting
1623  *    parent-node-0 from the child node.
1624  *
1625  * 4. bdrv_parent_drained_end() uses a QLIST_FOREACH_SAFE() loop to
1626  *    iterate over the parents.  Thus, it now accesses the BdrvChild
1627  *    object that used to connect parent-node-0 and the child node.
1628  *    However, that object no longer exists, so it accesses a dangling
1629  *    pointer.
1630  *
1631  * The solution is to only poll once when running a bdrv_drained_end()
1632  * operation, specifically at the end when all drained_end()
1633  * operations for all involved nodes have been scheduled.
1634  * Note that this also solves (A) above, thus hiding (B).
1635  */
1636 static void test_blockjob_commit_by_drained_end(void)
1637 {
1638     BlockDriverState *bs_child, *bs_parents[3];
1639     TestDropBackingBlockJob *job;
1640     bool job_has_completed = false;
1641     int i;
1642
1643     bs_child = bdrv_new_open_driver(&bdrv_test, "child-node", BDRV_O_RDWR,
1644                                     &error_abort);
1645
1646     for (i = 0; i < 3; i++) {
1647         char name[32];
1648         snprintf(name, sizeof(name), "parent-node-%i", i);
1649         bs_parents[i] = bdrv_new_open_driver(&bdrv_test, name, BDRV_O_RDWR,
1650                                              &error_abort);
1651         bdrv_set_backing_hd(bs_parents[i], bs_child, &error_abort);
1652     }
1653
1654     job = block_job_create("job", &test_drop_backing_job_driver, NULL,
1655                            bs_parents[2], 0, BLK_PERM_ALL, 0, 0, NULL, NULL,
1656                            &error_abort);
1657
1658     job->detach_also = bs_parents[0];
1659     job->did_complete = &job_has_completed;
1660
1661     job_start(&job->common.job);
1662
1663     job->should_complete = true;
1664     bdrv_drained_begin(bs_child);
1665     g_assert(!job_has_completed);
1666     bdrv_drained_end(bs_child);
1667     g_assert(job_has_completed);
1668
1669     bdrv_unref(bs_parents[0]);
1670     bdrv_unref(bs_parents[1]);
1671     bdrv_unref(bs_parents[2]);
1672     bdrv_unref(bs_child);
1673 }
1674
1675 int main(int argc, char **argv)
1676 {
1677     int ret;
1678
1679     bdrv_init();
1680     qemu_init_main_loop(&error_abort);
1681
1682     g_test_init(&argc, &argv, NULL);
1683     qemu_event_init(&done_event, false);
1684
1685     g_test_add_func("/bdrv-drain/driver-cb/drain_all", test_drv_cb_drain_all);
1686     g_test_add_func("/bdrv-drain/driver-cb/drain", test_drv_cb_drain);
1687     g_test_add_func("/bdrv-drain/driver-cb/drain_subtree",
1688                     test_drv_cb_drain_subtree);
1689
1690     g_test_add_func("/bdrv-drain/driver-cb/co/drain_all",
1691                     test_drv_cb_co_drain_all);
1692     g_test_add_func("/bdrv-drain/driver-cb/co/drain", test_drv_cb_co_drain);
1693     g_test_add_func("/bdrv-drain/driver-cb/co/drain_subtree",
1694                     test_drv_cb_co_drain_subtree);
1695
1696
1697     g_test_add_func("/bdrv-drain/quiesce/drain_all", test_quiesce_drain_all);
1698     g_test_add_func("/bdrv-drain/quiesce/drain", test_quiesce_drain);
1699     g_test_add_func("/bdrv-drain/quiesce/drain_subtree",
1700                     test_quiesce_drain_subtree);
1701
1702     g_test_add_func("/bdrv-drain/quiesce/co/drain_all",
1703                     test_quiesce_co_drain_all);
1704     g_test_add_func("/bdrv-drain/quiesce/co/drain", test_quiesce_co_drain);
1705     g_test_add_func("/bdrv-drain/quiesce/co/drain_subtree",
1706                     test_quiesce_co_drain_subtree);
1707
1708     g_test_add_func("/bdrv-drain/nested", test_nested);
1709     g_test_add_func("/bdrv-drain/multiparent", test_multiparent);
1710
1711     g_test_add_func("/bdrv-drain/graph-change/drain_subtree",
1712                     test_graph_change_drain_subtree);
1713     g_test_add_func("/bdrv-drain/graph-change/drain_all",
1714                     test_graph_change_drain_all);
1715
1716     g_test_add_func("/bdrv-drain/iothread/drain_all", test_iothread_drain_all);
1717     g_test_add_func("/bdrv-drain/iothread/drain", test_iothread_drain);
1718     g_test_add_func("/bdrv-drain/iothread/drain_subtree",
1719                     test_iothread_drain_subtree);
1720
1721     g_test_add_func("/bdrv-drain/blockjob/drain_all", test_blockjob_drain_all);
1722     g_test_add_func("/bdrv-drain/blockjob/drain", test_blockjob_drain);
1723     g_test_add_func("/bdrv-drain/blockjob/drain_subtree",
1724                     test_blockjob_drain_subtree);
1725
1726     g_test_add_func("/bdrv-drain/blockjob/error/drain_all",
1727                     test_blockjob_error_drain_all);
1728     g_test_add_func("/bdrv-drain/blockjob/error/drain",
1729                     test_blockjob_error_drain);
1730     g_test_add_func("/bdrv-drain/blockjob/error/drain_subtree",
1731                     test_blockjob_error_drain_subtree);
1732
1733     g_test_add_func("/bdrv-drain/blockjob/iothread/drain_all",
1734                     test_blockjob_iothread_drain_all);
1735     g_test_add_func("/bdrv-drain/blockjob/iothread/drain",
1736                     test_blockjob_iothread_drain);
1737     g_test_add_func("/bdrv-drain/blockjob/iothread/drain_subtree",
1738                     test_blockjob_iothread_drain_subtree);
1739
1740     g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain_all",
1741                     test_blockjob_iothread_error_drain_all);
1742     g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain",
1743                     test_blockjob_iothread_error_drain);
1744     g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain_subtree",
1745                     test_blockjob_iothread_error_drain_subtree);
1746
1747     g_test_add_func("/bdrv-drain/deletion/drain", test_delete_by_drain);
1748     g_test_add_func("/bdrv-drain/detach/drain_all", test_detach_by_drain_all);
1749     g_test_add_func("/bdrv-drain/detach/drain", test_detach_by_drain);
1750     g_test_add_func("/bdrv-drain/detach/drain_subtree", test_detach_by_drain_subtree);
1751     g_test_add_func("/bdrv-drain/detach/parent_cb", test_detach_by_parent_cb);
1752     g_test_add_func("/bdrv-drain/detach/driver_cb", test_detach_by_driver_cb);
1753
1754     g_test_add_func("/bdrv-drain/attach/drain", test_append_to_drained);
1755
1756     g_test_add_func("/bdrv-drain/set_aio_context", test_set_aio_context);
1757
1758     g_test_add_func("/bdrv-drain/blockjob/commit_by_drained_end",
1759                     test_blockjob_commit_by_drained_end);
1760
1761     ret = g_test_run();
1762     qemu_event_destroy(&done_event);
1763     return ret;
1764 }