1 /* 2 * Block node draining tests 3 * 4 * Copyright (c) 2017 Kevin Wolf <kwolf@redhat.com> 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 sleep_in_drain_begin(void *opaque) 42 { 43 BlockDriverState *bs = opaque; 44 45 qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000); 46 bdrv_dec_in_flight(bs); 47 } 48 49 static void bdrv_test_drain_begin(BlockDriverState *bs) 50 { 51 BDRVTestState *s = bs->opaque; 52 s->drain_count++; 53 if (s->sleep_in_drain_begin) { 54 Coroutine *co = qemu_coroutine_create(sleep_in_drain_begin, bs); 55 bdrv_inc_in_flight(bs); 56 aio_co_enter(bdrv_get_aio_context(bs), co); 57 } 58 } 59 60 static void bdrv_test_drain_end(BlockDriverState *bs) 61 { 62 BDRVTestState *s = bs->opaque; 63 s->drain_count--; 64 } 65 66 static void bdrv_test_close(BlockDriverState *bs) 67 { 68 BDRVTestState *s = bs->opaque; 69 g_assert_cmpint(s->drain_count, >, 0); 70 } 71 72 static void co_reenter_bh(void *opaque) 73 { 74 aio_co_wake(opaque); 75 } 76 77 static int coroutine_fn bdrv_test_co_preadv(BlockDriverState *bs, 78 int64_t offset, int64_t bytes, 79 QEMUIOVector *qiov, 80 BdrvRequestFlags flags) 81 { 82 BDRVTestState *s = bs->opaque; 83 84 /* We want this request to stay until the polling loop in drain waits for 85 * it to complete. We need to sleep a while as bdrv_drain_invoke() comes 86 * first and polls its result, too, but it shouldn't accidentally complete 87 * this request yet. */ 88 qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000); 89 90 if (s->bh_indirection_ctx) { 91 aio_bh_schedule_oneshot(s->bh_indirection_ctx, co_reenter_bh, 92 qemu_coroutine_self()); 93 qemu_coroutine_yield(); 94 } 95 96 return 0; 97 } 98 99 static int bdrv_test_change_backing_file(BlockDriverState *bs, 100 const char *backing_file, 101 const char *backing_fmt) 102 { 103 return 0; 104 } 105 106 static BlockDriver bdrv_test = { 107 .format_name = "test", 108 .instance_size = sizeof(BDRVTestState), 109 .supports_backing = true, 110 111 .bdrv_close = bdrv_test_close, 112 .bdrv_co_preadv = bdrv_test_co_preadv, 113 114 .bdrv_drain_begin = bdrv_test_drain_begin, 115 .bdrv_drain_end = bdrv_test_drain_end, 116 117 .bdrv_child_perm = bdrv_default_perms, 118 119 .bdrv_change_backing_file = bdrv_test_change_backing_file, 120 }; 121 122 static void aio_ret_cb(void *opaque, int ret) 123 { 124 int *aio_ret = opaque; 125 *aio_ret = ret; 126 } 127 128 typedef struct CallInCoroutineData { 129 void (*entry)(void); 130 bool done; 131 } CallInCoroutineData; 132 133 static coroutine_fn void call_in_coroutine_entry(void *opaque) 134 { 135 CallInCoroutineData *data = opaque; 136 137 data->entry(); 138 data->done = true; 139 } 140 141 static void call_in_coroutine(void (*entry)(void)) 142 { 143 Coroutine *co; 144 CallInCoroutineData data = { 145 .entry = entry, 146 .done = false, 147 }; 148 149 co = qemu_coroutine_create(call_in_coroutine_entry, &data); 150 qemu_coroutine_enter(co); 151 while (!data.done) { 152 aio_poll(qemu_get_aio_context(), true); 153 } 154 } 155 156 enum drain_type { 157 BDRV_DRAIN_ALL, 158 BDRV_DRAIN, 159 DRAIN_TYPE_MAX, 160 }; 161 162 static void do_drain_begin(enum drain_type drain_type, BlockDriverState *bs) 163 { 164 switch (drain_type) { 165 case BDRV_DRAIN_ALL: bdrv_drain_all_begin(); break; 166 case BDRV_DRAIN: bdrv_drained_begin(bs); break; 167 default: g_assert_not_reached(); 168 } 169 } 170 171 static void do_drain_end(enum drain_type drain_type, BlockDriverState *bs) 172 { 173 switch (drain_type) { 174 case BDRV_DRAIN_ALL: bdrv_drain_all_end(); break; 175 case BDRV_DRAIN: bdrv_drained_end(bs); break; 176 default: g_assert_not_reached(); 177 } 178 } 179 180 static void do_drain_begin_unlocked(enum drain_type drain_type, BlockDriverState *bs) 181 { 182 if (drain_type != BDRV_DRAIN_ALL) { 183 aio_context_acquire(bdrv_get_aio_context(bs)); 184 } 185 do_drain_begin(drain_type, bs); 186 if (drain_type != BDRV_DRAIN_ALL) { 187 aio_context_release(bdrv_get_aio_context(bs)); 188 } 189 } 190 191 static void do_drain_end_unlocked(enum drain_type drain_type, BlockDriverState *bs) 192 { 193 if (drain_type != BDRV_DRAIN_ALL) { 194 aio_context_acquire(bdrv_get_aio_context(bs)); 195 } 196 do_drain_end(drain_type, bs); 197 if (drain_type != BDRV_DRAIN_ALL) { 198 aio_context_release(bdrv_get_aio_context(bs)); 199 } 200 } 201 202 static void test_drv_cb_common(enum drain_type drain_type, bool recursive) 203 { 204 BlockBackend *blk; 205 BlockDriverState *bs, *backing; 206 BDRVTestState *s, *backing_s; 207 BlockAIOCB *acb; 208 int aio_ret; 209 210 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, 0); 211 212 blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 213 bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR, 214 &error_abort); 215 s = bs->opaque; 216 blk_insert_bs(blk, bs, &error_abort); 217 218 backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort); 219 backing_s = backing->opaque; 220 bdrv_set_backing_hd(bs, backing, &error_abort); 221 222 /* Simple bdrv_drain_all_begin/end pair, check that CBs are called */ 223 g_assert_cmpint(s->drain_count, ==, 0); 224 g_assert_cmpint(backing_s->drain_count, ==, 0); 225 226 do_drain_begin(drain_type, bs); 227 228 g_assert_cmpint(s->drain_count, ==, 1); 229 g_assert_cmpint(backing_s->drain_count, ==, !!recursive); 230 231 do_drain_end(drain_type, bs); 232 233 g_assert_cmpint(s->drain_count, ==, 0); 234 g_assert_cmpint(backing_s->drain_count, ==, 0); 235 236 /* Now do the same while a request is pending */ 237 aio_ret = -EINPROGRESS; 238 acb = blk_aio_preadv(blk, 0, &qiov, 0, aio_ret_cb, &aio_ret); 239 g_assert(acb != NULL); 240 g_assert_cmpint(aio_ret, ==, -EINPROGRESS); 241 242 g_assert_cmpint(s->drain_count, ==, 0); 243 g_assert_cmpint(backing_s->drain_count, ==, 0); 244 245 do_drain_begin(drain_type, bs); 246 247 g_assert_cmpint(aio_ret, ==, 0); 248 g_assert_cmpint(s->drain_count, ==, 1); 249 g_assert_cmpint(backing_s->drain_count, ==, !!recursive); 250 251 do_drain_end(drain_type, bs); 252 253 g_assert_cmpint(s->drain_count, ==, 0); 254 g_assert_cmpint(backing_s->drain_count, ==, 0); 255 256 bdrv_unref(backing); 257 bdrv_unref(bs); 258 blk_unref(blk); 259 } 260 261 static void test_drv_cb_drain_all(void) 262 { 263 test_drv_cb_common(BDRV_DRAIN_ALL, true); 264 } 265 266 static void test_drv_cb_drain(void) 267 { 268 test_drv_cb_common(BDRV_DRAIN, false); 269 } 270 271 static void test_drv_cb_co_drain_all(void) 272 { 273 call_in_coroutine(test_drv_cb_drain_all); 274 } 275 276 static void test_drv_cb_co_drain(void) 277 { 278 call_in_coroutine(test_drv_cb_drain); 279 } 280 281 static void test_quiesce_common(enum drain_type drain_type, bool recursive) 282 { 283 BlockBackend *blk; 284 BlockDriverState *bs, *backing; 285 286 blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 287 bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR, 288 &error_abort); 289 blk_insert_bs(blk, bs, &error_abort); 290 291 backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort); 292 bdrv_set_backing_hd(bs, backing, &error_abort); 293 294 g_assert_cmpint(bs->quiesce_counter, ==, 0); 295 g_assert_cmpint(backing->quiesce_counter, ==, 0); 296 297 do_drain_begin(drain_type, bs); 298 299 if (drain_type == BDRV_DRAIN_ALL) { 300 g_assert_cmpint(bs->quiesce_counter, ==, 2); 301 } else { 302 g_assert_cmpint(bs->quiesce_counter, ==, 1); 303 } 304 g_assert_cmpint(backing->quiesce_counter, ==, !!recursive); 305 306 do_drain_end(drain_type, bs); 307 308 g_assert_cmpint(bs->quiesce_counter, ==, 0); 309 g_assert_cmpint(backing->quiesce_counter, ==, 0); 310 311 bdrv_unref(backing); 312 bdrv_unref(bs); 313 blk_unref(blk); 314 } 315 316 static void test_quiesce_drain_all(void) 317 { 318 test_quiesce_common(BDRV_DRAIN_ALL, true); 319 } 320 321 static void test_quiesce_drain(void) 322 { 323 test_quiesce_common(BDRV_DRAIN, false); 324 } 325 326 static void test_quiesce_co_drain_all(void) 327 { 328 call_in_coroutine(test_quiesce_drain_all); 329 } 330 331 static void test_quiesce_co_drain(void) 332 { 333 call_in_coroutine(test_quiesce_drain); 334 } 335 336 static void test_nested(void) 337 { 338 BlockBackend *blk; 339 BlockDriverState *bs, *backing; 340 BDRVTestState *s, *backing_s; 341 enum drain_type outer, inner; 342 343 blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 344 bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR, 345 &error_abort); 346 s = bs->opaque; 347 blk_insert_bs(blk, bs, &error_abort); 348 349 backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort); 350 backing_s = backing->opaque; 351 bdrv_set_backing_hd(bs, backing, &error_abort); 352 353 for (outer = 0; outer < DRAIN_TYPE_MAX; outer++) { 354 for (inner = 0; inner < DRAIN_TYPE_MAX; inner++) { 355 int backing_quiesce = (outer == BDRV_DRAIN_ALL) + 356 (inner == BDRV_DRAIN_ALL); 357 358 g_assert_cmpint(bs->quiesce_counter, ==, 0); 359 g_assert_cmpint(backing->quiesce_counter, ==, 0); 360 g_assert_cmpint(s->drain_count, ==, 0); 361 g_assert_cmpint(backing_s->drain_count, ==, 0); 362 363 do_drain_begin(outer, bs); 364 do_drain_begin(inner, bs); 365 366 g_assert_cmpint(bs->quiesce_counter, ==, 2 + !!backing_quiesce); 367 g_assert_cmpint(backing->quiesce_counter, ==, backing_quiesce); 368 g_assert_cmpint(s->drain_count, ==, 1); 369 g_assert_cmpint(backing_s->drain_count, ==, !!backing_quiesce); 370 371 do_drain_end(inner, bs); 372 do_drain_end(outer, bs); 373 374 g_assert_cmpint(bs->quiesce_counter, ==, 0); 375 g_assert_cmpint(backing->quiesce_counter, ==, 0); 376 g_assert_cmpint(s->drain_count, ==, 0); 377 g_assert_cmpint(backing_s->drain_count, ==, 0); 378 } 379 } 380 381 bdrv_unref(backing); 382 bdrv_unref(bs); 383 blk_unref(blk); 384 } 385 386 static void test_graph_change_drain_all(void) 387 { 388 BlockBackend *blk_a, *blk_b; 389 BlockDriverState *bs_a, *bs_b; 390 BDRVTestState *a_s, *b_s; 391 392 /* Create node A with a BlockBackend */ 393 blk_a = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 394 bs_a = bdrv_new_open_driver(&bdrv_test, "test-node-a", BDRV_O_RDWR, 395 &error_abort); 396 a_s = bs_a->opaque; 397 blk_insert_bs(blk_a, bs_a, &error_abort); 398 399 g_assert_cmpint(bs_a->quiesce_counter, ==, 0); 400 g_assert_cmpint(a_s->drain_count, ==, 0); 401 402 /* Call bdrv_drain_all_begin() */ 403 bdrv_drain_all_begin(); 404 405 g_assert_cmpint(bs_a->quiesce_counter, ==, 1); 406 g_assert_cmpint(a_s->drain_count, ==, 1); 407 408 /* Create node B with a BlockBackend */ 409 blk_b = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 410 bs_b = bdrv_new_open_driver(&bdrv_test, "test-node-b", BDRV_O_RDWR, 411 &error_abort); 412 b_s = bs_b->opaque; 413 blk_insert_bs(blk_b, bs_b, &error_abort); 414 415 g_assert_cmpint(bs_a->quiesce_counter, ==, 1); 416 g_assert_cmpint(bs_b->quiesce_counter, ==, 1); 417 g_assert_cmpint(a_s->drain_count, ==, 1); 418 g_assert_cmpint(b_s->drain_count, ==, 1); 419 420 /* Unref and finally delete node A */ 421 blk_unref(blk_a); 422 423 g_assert_cmpint(bs_a->quiesce_counter, ==, 1); 424 g_assert_cmpint(bs_b->quiesce_counter, ==, 1); 425 g_assert_cmpint(a_s->drain_count, ==, 1); 426 g_assert_cmpint(b_s->drain_count, ==, 1); 427 428 bdrv_unref(bs_a); 429 430 g_assert_cmpint(bs_b->quiesce_counter, ==, 1); 431 g_assert_cmpint(b_s->drain_count, ==, 1); 432 433 /* End the drained section */ 434 bdrv_drain_all_end(); 435 436 g_assert_cmpint(bs_b->quiesce_counter, ==, 0); 437 g_assert_cmpint(b_s->drain_count, ==, 0); 438 g_assert_cmpint(qemu_get_aio_context()->external_disable_cnt, ==, 0); 439 440 bdrv_unref(bs_b); 441 blk_unref(blk_b); 442 } 443 444 struct test_iothread_data { 445 BlockDriverState *bs; 446 enum drain_type drain_type; 447 int *aio_ret; 448 }; 449 450 static void test_iothread_drain_entry(void *opaque) 451 { 452 struct test_iothread_data *data = opaque; 453 454 aio_context_acquire(bdrv_get_aio_context(data->bs)); 455 do_drain_begin(data->drain_type, data->bs); 456 g_assert_cmpint(*data->aio_ret, ==, 0); 457 do_drain_end(data->drain_type, data->bs); 458 aio_context_release(bdrv_get_aio_context(data->bs)); 459 460 qemu_event_set(&done_event); 461 } 462 463 static void test_iothread_aio_cb(void *opaque, int ret) 464 { 465 int *aio_ret = opaque; 466 *aio_ret = ret; 467 qemu_event_set(&done_event); 468 } 469 470 static void test_iothread_main_thread_bh(void *opaque) 471 { 472 struct test_iothread_data *data = opaque; 473 474 /* Test that the AioContext is not yet locked in a random BH that is 475 * executed during drain, otherwise this would deadlock. */ 476 aio_context_acquire(bdrv_get_aio_context(data->bs)); 477 bdrv_flush(data->bs); 478 aio_context_release(bdrv_get_aio_context(data->bs)); 479 } 480 481 /* 482 * Starts an AIO request on a BDS that runs in the AioContext of iothread 1. 483 * The request involves a BH on iothread 2 before it can complete. 484 * 485 * @drain_thread = 0 means that do_drain_begin/end are called from the main 486 * thread, @drain_thread = 1 means that they are called from iothread 1. Drain 487 * for this BDS cannot be called from iothread 2 because only the main thread 488 * may do cross-AioContext polling. 489 */ 490 static void test_iothread_common(enum drain_type drain_type, int drain_thread) 491 { 492 BlockBackend *blk; 493 BlockDriverState *bs; 494 BDRVTestState *s; 495 BlockAIOCB *acb; 496 int aio_ret; 497 struct test_iothread_data data; 498 499 IOThread *a = iothread_new(); 500 IOThread *b = iothread_new(); 501 AioContext *ctx_a = iothread_get_aio_context(a); 502 AioContext *ctx_b = iothread_get_aio_context(b); 503 504 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, 0); 505 506 /* bdrv_drain_all() may only be called from the main loop thread */ 507 if (drain_type == BDRV_DRAIN_ALL && drain_thread != 0) { 508 goto out; 509 } 510 511 blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 512 bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR, 513 &error_abort); 514 s = bs->opaque; 515 blk_insert_bs(blk, bs, &error_abort); 516 blk_set_disable_request_queuing(blk, true); 517 518 blk_set_aio_context(blk, ctx_a, &error_abort); 519 aio_context_acquire(ctx_a); 520 521 s->bh_indirection_ctx = ctx_b; 522 523 aio_ret = -EINPROGRESS; 524 qemu_event_reset(&done_event); 525 526 if (drain_thread == 0) { 527 acb = blk_aio_preadv(blk, 0, &qiov, 0, test_iothread_aio_cb, &aio_ret); 528 } else { 529 acb = blk_aio_preadv(blk, 0, &qiov, 0, aio_ret_cb, &aio_ret); 530 } 531 g_assert(acb != NULL); 532 g_assert_cmpint(aio_ret, ==, -EINPROGRESS); 533 534 aio_context_release(ctx_a); 535 536 data = (struct test_iothread_data) { 537 .bs = bs, 538 .drain_type = drain_type, 539 .aio_ret = &aio_ret, 540 }; 541 542 switch (drain_thread) { 543 case 0: 544 if (drain_type != BDRV_DRAIN_ALL) { 545 aio_context_acquire(ctx_a); 546 } 547 548 aio_bh_schedule_oneshot(ctx_a, test_iothread_main_thread_bh, &data); 549 550 /* The request is running on the IOThread a. Draining its block device 551 * will make sure that it has completed as far as the BDS is concerned, 552 * but the drain in this thread can continue immediately after 553 * bdrv_dec_in_flight() and aio_ret might be assigned only slightly 554 * later. */ 555 do_drain_begin(drain_type, bs); 556 g_assert_cmpint(bs->in_flight, ==, 0); 557 558 if (drain_type != BDRV_DRAIN_ALL) { 559 aio_context_release(ctx_a); 560 } 561 qemu_event_wait(&done_event); 562 if (drain_type != BDRV_DRAIN_ALL) { 563 aio_context_acquire(ctx_a); 564 } 565 566 g_assert_cmpint(aio_ret, ==, 0); 567 do_drain_end(drain_type, bs); 568 569 if (drain_type != BDRV_DRAIN_ALL) { 570 aio_context_release(ctx_a); 571 } 572 break; 573 case 1: 574 aio_bh_schedule_oneshot(ctx_a, test_iothread_drain_entry, &data); 575 qemu_event_wait(&done_event); 576 break; 577 default: 578 g_assert_not_reached(); 579 } 580 581 aio_context_acquire(ctx_a); 582 blk_set_aio_context(blk, qemu_get_aio_context(), &error_abort); 583 aio_context_release(ctx_a); 584 585 bdrv_unref(bs); 586 blk_unref(blk); 587 588 out: 589 iothread_join(a); 590 iothread_join(b); 591 } 592 593 static void test_iothread_drain_all(void) 594 { 595 test_iothread_common(BDRV_DRAIN_ALL, 0); 596 test_iothread_common(BDRV_DRAIN_ALL, 1); 597 } 598 599 static void test_iothread_drain(void) 600 { 601 test_iothread_common(BDRV_DRAIN, 0); 602 test_iothread_common(BDRV_DRAIN, 1); 603 } 604 605 606 typedef struct TestBlockJob { 607 BlockJob common; 608 BlockDriverState *bs; 609 int run_ret; 610 int prepare_ret; 611 bool running; 612 bool should_complete; 613 } TestBlockJob; 614 615 static int test_job_prepare(Job *job) 616 { 617 TestBlockJob *s = container_of(job, TestBlockJob, common.job); 618 619 /* Provoke an AIO_WAIT_WHILE() call to verify there is no deadlock */ 620 bdrv_flush(s->bs); 621 return s->prepare_ret; 622 } 623 624 static void test_job_commit(Job *job) 625 { 626 TestBlockJob *s = container_of(job, TestBlockJob, common.job); 627 628 /* Provoke an AIO_WAIT_WHILE() call to verify there is no deadlock */ 629 bdrv_flush(s->bs); 630 } 631 632 static void test_job_abort(Job *job) 633 { 634 TestBlockJob *s = container_of(job, TestBlockJob, common.job); 635 636 /* Provoke an AIO_WAIT_WHILE() call to verify there is no deadlock */ 637 bdrv_flush(s->bs); 638 } 639 640 static int coroutine_fn test_job_run(Job *job, Error **errp) 641 { 642 TestBlockJob *s = container_of(job, TestBlockJob, common.job); 643 644 /* We are running the actual job code past the pause point in 645 * job_co_entry(). */ 646 s->running = true; 647 648 job_transition_to_ready(&s->common.job); 649 while (!s->should_complete) { 650 /* Avoid job_sleep_ns() because it marks the job as !busy. We want to 651 * emulate some actual activity (probably some I/O) here so that drain 652 * has to wait for this activity to stop. */ 653 qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 1000000); 654 655 job_pause_point(&s->common.job); 656 } 657 658 return s->run_ret; 659 } 660 661 static void test_job_complete(Job *job, Error **errp) 662 { 663 TestBlockJob *s = container_of(job, TestBlockJob, common.job); 664 s->should_complete = true; 665 } 666 667 BlockJobDriver test_job_driver = { 668 .job_driver = { 669 .instance_size = sizeof(TestBlockJob), 670 .free = block_job_free, 671 .user_resume = block_job_user_resume, 672 .run = test_job_run, 673 .complete = test_job_complete, 674 .prepare = test_job_prepare, 675 .commit = test_job_commit, 676 .abort = test_job_abort, 677 }, 678 }; 679 680 enum test_job_result { 681 TEST_JOB_SUCCESS, 682 TEST_JOB_FAIL_RUN, 683 TEST_JOB_FAIL_PREPARE, 684 }; 685 686 enum test_job_drain_node { 687 TEST_JOB_DRAIN_SRC, 688 TEST_JOB_DRAIN_SRC_CHILD, 689 }; 690 691 static void test_blockjob_common_drain_node(enum drain_type drain_type, 692 bool use_iothread, 693 enum test_job_result result, 694 enum test_job_drain_node drain_node) 695 { 696 BlockBackend *blk_src, *blk_target; 697 BlockDriverState *src, *src_backing, *src_overlay, *target, *drain_bs; 698 BlockJob *job; 699 TestBlockJob *tjob; 700 IOThread *iothread = NULL; 701 AioContext *ctx; 702 int ret; 703 704 src = bdrv_new_open_driver(&bdrv_test, "source", BDRV_O_RDWR, 705 &error_abort); 706 src_backing = bdrv_new_open_driver(&bdrv_test, "source-backing", 707 BDRV_O_RDWR, &error_abort); 708 src_overlay = bdrv_new_open_driver(&bdrv_test, "source-overlay", 709 BDRV_O_RDWR, &error_abort); 710 711 bdrv_set_backing_hd(src_overlay, src, &error_abort); 712 bdrv_unref(src); 713 bdrv_set_backing_hd(src, src_backing, &error_abort); 714 bdrv_unref(src_backing); 715 716 blk_src = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 717 blk_insert_bs(blk_src, src_overlay, &error_abort); 718 719 switch (drain_node) { 720 case TEST_JOB_DRAIN_SRC: 721 drain_bs = src; 722 break; 723 case TEST_JOB_DRAIN_SRC_CHILD: 724 drain_bs = src_backing; 725 break; 726 default: 727 g_assert_not_reached(); 728 } 729 730 if (use_iothread) { 731 iothread = iothread_new(); 732 ctx = iothread_get_aio_context(iothread); 733 blk_set_aio_context(blk_src, ctx, &error_abort); 734 } else { 735 ctx = qemu_get_aio_context(); 736 } 737 738 target = bdrv_new_open_driver(&bdrv_test, "target", BDRV_O_RDWR, 739 &error_abort); 740 blk_target = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 741 blk_insert_bs(blk_target, target, &error_abort); 742 blk_set_allow_aio_context_change(blk_target, true); 743 744 aio_context_acquire(ctx); 745 tjob = block_job_create("job0", &test_job_driver, NULL, src, 746 0, BLK_PERM_ALL, 747 0, 0, NULL, NULL, &error_abort); 748 tjob->bs = src; 749 job = &tjob->common; 750 block_job_add_bdrv(job, "target", target, 0, BLK_PERM_ALL, &error_abort); 751 752 switch (result) { 753 case TEST_JOB_SUCCESS: 754 break; 755 case TEST_JOB_FAIL_RUN: 756 tjob->run_ret = -EIO; 757 break; 758 case TEST_JOB_FAIL_PREPARE: 759 tjob->prepare_ret = -EIO; 760 break; 761 } 762 aio_context_release(ctx); 763 764 job_start(&job->job); 765 766 if (use_iothread) { 767 /* job_co_entry() is run in the I/O thread, wait for the actual job 768 * code to start (we don't want to catch the job in the pause point in 769 * job_co_entry(). */ 770 while (!tjob->running) { 771 aio_poll(qemu_get_aio_context(), false); 772 } 773 } 774 775 WITH_JOB_LOCK_GUARD() { 776 g_assert_cmpint(job->job.pause_count, ==, 0); 777 g_assert_false(job->job.paused); 778 g_assert_true(tjob->running); 779 g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */ 780 } 781 782 do_drain_begin_unlocked(drain_type, drain_bs); 783 784 WITH_JOB_LOCK_GUARD() { 785 if (drain_type == BDRV_DRAIN_ALL) { 786 /* bdrv_drain_all() drains both src and target */ 787 g_assert_cmpint(job->job.pause_count, ==, 2); 788 } else { 789 g_assert_cmpint(job->job.pause_count, ==, 1); 790 } 791 g_assert_true(job->job.paused); 792 g_assert_false(job->job.busy); /* The job is paused */ 793 } 794 795 do_drain_end_unlocked(drain_type, drain_bs); 796 797 if (use_iothread) { 798 /* 799 * Here we are waiting for the paused status to change, 800 * so don't bother protecting the read every time. 801 * 802 * paused is reset in the I/O thread, wait for it 803 */ 804 while (job->job.paused) { 805 aio_poll(qemu_get_aio_context(), false); 806 } 807 } 808 809 WITH_JOB_LOCK_GUARD() { 810 g_assert_cmpint(job->job.pause_count, ==, 0); 811 g_assert_false(job->job.paused); 812 g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */ 813 } 814 815 do_drain_begin_unlocked(drain_type, target); 816 817 WITH_JOB_LOCK_GUARD() { 818 if (drain_type == BDRV_DRAIN_ALL) { 819 /* bdrv_drain_all() drains both src and target */ 820 g_assert_cmpint(job->job.pause_count, ==, 2); 821 } else { 822 g_assert_cmpint(job->job.pause_count, ==, 1); 823 } 824 g_assert_true(job->job.paused); 825 g_assert_false(job->job.busy); /* The job is paused */ 826 } 827 828 do_drain_end_unlocked(drain_type, target); 829 830 if (use_iothread) { 831 /* 832 * Here we are waiting for the paused status to change, 833 * so don't bother protecting the read every time. 834 * 835 * paused is reset in the I/O thread, wait for it 836 */ 837 while (job->job.paused) { 838 aio_poll(qemu_get_aio_context(), false); 839 } 840 } 841 842 WITH_JOB_LOCK_GUARD() { 843 g_assert_cmpint(job->job.pause_count, ==, 0); 844 g_assert_false(job->job.paused); 845 g_assert_true(job->job.busy); /* We're in qemu_co_sleep_ns() */ 846 } 847 848 WITH_JOB_LOCK_GUARD() { 849 ret = job_complete_sync_locked(&job->job, &error_abort); 850 } 851 g_assert_cmpint(ret, ==, (result == TEST_JOB_SUCCESS ? 0 : -EIO)); 852 853 aio_context_acquire(ctx); 854 if (use_iothread) { 855 blk_set_aio_context(blk_src, qemu_get_aio_context(), &error_abort); 856 assert(blk_get_aio_context(blk_target) == qemu_get_aio_context()); 857 } 858 aio_context_release(ctx); 859 860 blk_unref(blk_src); 861 blk_unref(blk_target); 862 bdrv_unref(src_overlay); 863 bdrv_unref(target); 864 865 if (iothread) { 866 iothread_join(iothread); 867 } 868 } 869 870 static void test_blockjob_common(enum drain_type drain_type, bool use_iothread, 871 enum test_job_result result) 872 { 873 test_blockjob_common_drain_node(drain_type, use_iothread, result, 874 TEST_JOB_DRAIN_SRC); 875 test_blockjob_common_drain_node(drain_type, use_iothread, result, 876 TEST_JOB_DRAIN_SRC_CHILD); 877 } 878 879 static void test_blockjob_drain_all(void) 880 { 881 test_blockjob_common(BDRV_DRAIN_ALL, false, TEST_JOB_SUCCESS); 882 } 883 884 static void test_blockjob_drain(void) 885 { 886 test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_SUCCESS); 887 } 888 889 static void test_blockjob_error_drain_all(void) 890 { 891 test_blockjob_common(BDRV_DRAIN_ALL, false, TEST_JOB_FAIL_RUN); 892 test_blockjob_common(BDRV_DRAIN_ALL, false, TEST_JOB_FAIL_PREPARE); 893 } 894 895 static void test_blockjob_error_drain(void) 896 { 897 test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_FAIL_RUN); 898 test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_FAIL_PREPARE); 899 } 900 901 static void test_blockjob_iothread_drain_all(void) 902 { 903 test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_SUCCESS); 904 } 905 906 static void test_blockjob_iothread_drain(void) 907 { 908 test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_SUCCESS); 909 } 910 911 static void test_blockjob_iothread_error_drain_all(void) 912 { 913 test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_FAIL_RUN); 914 test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_FAIL_PREPARE); 915 } 916 917 static void test_blockjob_iothread_error_drain(void) 918 { 919 test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_FAIL_RUN); 920 test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_FAIL_PREPARE); 921 } 922 923 924 typedef struct BDRVTestTopState { 925 BdrvChild *wait_child; 926 } BDRVTestTopState; 927 928 static void bdrv_test_top_close(BlockDriverState *bs) 929 { 930 BdrvChild *c, *next_c; 931 QLIST_FOREACH_SAFE(c, &bs->children, next, next_c) { 932 bdrv_unref_child(bs, c); 933 } 934 } 935 936 static int coroutine_fn bdrv_test_top_co_preadv(BlockDriverState *bs, 937 int64_t offset, int64_t bytes, 938 QEMUIOVector *qiov, 939 BdrvRequestFlags flags) 940 { 941 BDRVTestTopState *tts = bs->opaque; 942 return bdrv_co_preadv(tts->wait_child, offset, bytes, qiov, flags); 943 } 944 945 static BlockDriver bdrv_test_top_driver = { 946 .format_name = "test_top_driver", 947 .instance_size = sizeof(BDRVTestTopState), 948 949 .bdrv_close = bdrv_test_top_close, 950 .bdrv_co_preadv = bdrv_test_top_co_preadv, 951 952 .bdrv_child_perm = bdrv_default_perms, 953 }; 954 955 typedef struct TestCoDeleteByDrainData { 956 BlockBackend *blk; 957 bool detach_instead_of_delete; 958 bool done; 959 } TestCoDeleteByDrainData; 960 961 static void coroutine_fn test_co_delete_by_drain(void *opaque) 962 { 963 TestCoDeleteByDrainData *dbdd = opaque; 964 BlockBackend *blk = dbdd->blk; 965 BlockDriverState *bs = blk_bs(blk); 966 BDRVTestTopState *tts = bs->opaque; 967 void *buffer = g_malloc(65536); 968 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buffer, 65536); 969 970 /* Pretend some internal write operation from parent to child. 971 * Important: We have to read from the child, not from the parent! 972 * Draining works by first propagating it all up the tree to the 973 * root and then waiting for drainage from root to the leaves 974 * (protocol nodes). If we have a request waiting on the root, 975 * everything will be drained before we go back down the tree, but 976 * we do not want that. We want to be in the middle of draining 977 * when this following requests returns. */ 978 bdrv_co_preadv(tts->wait_child, 0, 65536, &qiov, 0); 979 980 g_assert_cmpint(bs->refcnt, ==, 1); 981 982 if (!dbdd->detach_instead_of_delete) { 983 blk_unref(blk); 984 } else { 985 BdrvChild *c, *next_c; 986 QLIST_FOREACH_SAFE(c, &bs->children, next, next_c) { 987 bdrv_unref_child(bs, c); 988 } 989 } 990 991 dbdd->done = true; 992 g_free(buffer); 993 } 994 995 /** 996 * Test what happens when some BDS has some children, you drain one of 997 * them and this results in the BDS being deleted. 998 * 999 * If @detach_instead_of_delete is set, the BDS is not going to be 1000 * deleted but will only detach all of its children. 1001 */ 1002 static void do_test_delete_by_drain(bool detach_instead_of_delete, 1003 enum drain_type drain_type) 1004 { 1005 BlockBackend *blk; 1006 BlockDriverState *bs, *child_bs, *null_bs; 1007 BDRVTestTopState *tts; 1008 TestCoDeleteByDrainData dbdd; 1009 Coroutine *co; 1010 1011 bs = bdrv_new_open_driver(&bdrv_test_top_driver, "top", BDRV_O_RDWR, 1012 &error_abort); 1013 bs->total_sectors = 65536 >> BDRV_SECTOR_BITS; 1014 tts = bs->opaque; 1015 1016 null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, 1017 &error_abort); 1018 bdrv_attach_child(bs, null_bs, "null-child", &child_of_bds, 1019 BDRV_CHILD_DATA, &error_abort); 1020 1021 /* This child will be the one to pass to requests through to, and 1022 * it will stall until a drain occurs */ 1023 child_bs = bdrv_new_open_driver(&bdrv_test, "child", BDRV_O_RDWR, 1024 &error_abort); 1025 child_bs->total_sectors = 65536 >> BDRV_SECTOR_BITS; 1026 /* Takes our reference to child_bs */ 1027 tts->wait_child = bdrv_attach_child(bs, child_bs, "wait-child", 1028 &child_of_bds, 1029 BDRV_CHILD_DATA | BDRV_CHILD_PRIMARY, 1030 &error_abort); 1031 1032 /* This child is just there to be deleted 1033 * (for detach_instead_of_delete == true) */ 1034 null_bs = bdrv_open("null-co://", NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, 1035 &error_abort); 1036 bdrv_attach_child(bs, null_bs, "null-child", &child_of_bds, BDRV_CHILD_DATA, 1037 &error_abort); 1038 1039 blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 1040 blk_insert_bs(blk, bs, &error_abort); 1041 1042 /* Referenced by blk now */ 1043 bdrv_unref(bs); 1044 1045 g_assert_cmpint(bs->refcnt, ==, 1); 1046 g_assert_cmpint(child_bs->refcnt, ==, 1); 1047 g_assert_cmpint(null_bs->refcnt, ==, 1); 1048 1049 1050 dbdd = (TestCoDeleteByDrainData){ 1051 .blk = blk, 1052 .detach_instead_of_delete = detach_instead_of_delete, 1053 .done = false, 1054 }; 1055 co = qemu_coroutine_create(test_co_delete_by_drain, &dbdd); 1056 qemu_coroutine_enter(co); 1057 1058 /* Drain the child while the read operation is still pending. 1059 * This should result in the operation finishing and 1060 * test_co_delete_by_drain() resuming. Thus, @bs will be deleted 1061 * and the coroutine will exit while this drain operation is still 1062 * in progress. */ 1063 switch (drain_type) { 1064 case BDRV_DRAIN: 1065 bdrv_ref(child_bs); 1066 bdrv_drain(child_bs); 1067 bdrv_unref(child_bs); 1068 break; 1069 case BDRV_DRAIN_ALL: 1070 bdrv_drain_all_begin(); 1071 bdrv_drain_all_end(); 1072 break; 1073 default: 1074 g_assert_not_reached(); 1075 } 1076 1077 while (!dbdd.done) { 1078 aio_poll(qemu_get_aio_context(), true); 1079 } 1080 1081 if (detach_instead_of_delete) { 1082 /* Here, the reference has not passed over to the coroutine, 1083 * so we have to delete the BB ourselves */ 1084 blk_unref(blk); 1085 } 1086 } 1087 1088 static void test_delete_by_drain(void) 1089 { 1090 do_test_delete_by_drain(false, BDRV_DRAIN); 1091 } 1092 1093 static void test_detach_by_drain_all(void) 1094 { 1095 do_test_delete_by_drain(true, BDRV_DRAIN_ALL); 1096 } 1097 1098 static void test_detach_by_drain(void) 1099 { 1100 do_test_delete_by_drain(true, BDRV_DRAIN); 1101 } 1102 1103 1104 struct detach_by_parent_data { 1105 BlockDriverState *parent_b; 1106 BdrvChild *child_b; 1107 BlockDriverState *c; 1108 BdrvChild *child_c; 1109 bool by_parent_cb; 1110 bool detach_on_drain; 1111 }; 1112 static struct detach_by_parent_data detach_by_parent_data; 1113 1114 static void detach_indirect_bh(void *opaque) 1115 { 1116 struct detach_by_parent_data *data = opaque; 1117 1118 bdrv_dec_in_flight(data->child_b->bs); 1119 bdrv_unref_child(data->parent_b, data->child_b); 1120 1121 bdrv_ref(data->c); 1122 data->child_c = bdrv_attach_child(data->parent_b, data->c, "PB-C", 1123 &child_of_bds, BDRV_CHILD_DATA, 1124 &error_abort); 1125 } 1126 1127 static void detach_by_parent_aio_cb(void *opaque, int ret) 1128 { 1129 struct detach_by_parent_data *data = &detach_by_parent_data; 1130 1131 g_assert_cmpint(ret, ==, 0); 1132 if (data->by_parent_cb) { 1133 bdrv_inc_in_flight(data->child_b->bs); 1134 detach_indirect_bh(data); 1135 } 1136 } 1137 1138 static void detach_by_driver_cb_drained_begin(BdrvChild *child) 1139 { 1140 struct detach_by_parent_data *data = &detach_by_parent_data; 1141 1142 if (!data->detach_on_drain) { 1143 return; 1144 } 1145 data->detach_on_drain = false; 1146 1147 bdrv_inc_in_flight(data->child_b->bs); 1148 aio_bh_schedule_oneshot(qemu_get_current_aio_context(), 1149 detach_indirect_bh, &detach_by_parent_data); 1150 child_of_bds.drained_begin(child); 1151 } 1152 1153 static BdrvChildClass detach_by_driver_cb_class; 1154 1155 /* 1156 * Initial graph: 1157 * 1158 * PA PB 1159 * \ / \ 1160 * A B C 1161 * 1162 * by_parent_cb == true: Test that parent callbacks don't poll 1163 * 1164 * PA has a pending write request whose callback changes the child nodes of 1165 * PB: It removes B and adds C instead. The subtree of PB is drained, which 1166 * will indirectly drain the write request, too. 1167 * 1168 * by_parent_cb == false: Test that bdrv_drain_invoke() doesn't poll 1169 * 1170 * PA's BdrvChildClass has a .drained_begin callback that schedules a BH 1171 * that does the same graph change. If bdrv_drain_invoke() calls it, the 1172 * state is messed up, but if it is only polled in the single 1173 * BDRV_POLL_WHILE() at the end of the drain, this should work fine. 1174 */ 1175 static void test_detach_indirect(bool by_parent_cb) 1176 { 1177 BlockBackend *blk; 1178 BlockDriverState *parent_a, *parent_b, *a, *b, *c; 1179 BdrvChild *child_a, *child_b; 1180 BlockAIOCB *acb; 1181 1182 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, 0); 1183 1184 if (!by_parent_cb) { 1185 detach_by_driver_cb_class = child_of_bds; 1186 detach_by_driver_cb_class.drained_begin = 1187 detach_by_driver_cb_drained_begin; 1188 detach_by_driver_cb_class.drained_end = NULL; 1189 detach_by_driver_cb_class.drained_poll = NULL; 1190 } 1191 1192 detach_by_parent_data = (struct detach_by_parent_data) { 1193 .detach_on_drain = false, 1194 }; 1195 1196 /* Create all involved nodes */ 1197 parent_a = bdrv_new_open_driver(&bdrv_test, "parent-a", BDRV_O_RDWR, 1198 &error_abort); 1199 parent_b = bdrv_new_open_driver(&bdrv_test, "parent-b", 0, 1200 &error_abort); 1201 1202 a = bdrv_new_open_driver(&bdrv_test, "a", BDRV_O_RDWR, &error_abort); 1203 b = bdrv_new_open_driver(&bdrv_test, "b", BDRV_O_RDWR, &error_abort); 1204 c = bdrv_new_open_driver(&bdrv_test, "c", BDRV_O_RDWR, &error_abort); 1205 1206 /* blk is a BB for parent-a */ 1207 blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 1208 blk_insert_bs(blk, parent_a, &error_abort); 1209 bdrv_unref(parent_a); 1210 1211 /* If we want to get bdrv_drain_invoke() to call aio_poll(), the driver 1212 * callback must not return immediately. */ 1213 if (!by_parent_cb) { 1214 BDRVTestState *s = parent_a->opaque; 1215 s->sleep_in_drain_begin = true; 1216 } 1217 1218 /* Set child relationships */ 1219 bdrv_ref(b); 1220 bdrv_ref(a); 1221 child_b = bdrv_attach_child(parent_b, b, "PB-B", &child_of_bds, 1222 BDRV_CHILD_DATA, &error_abort); 1223 child_a = bdrv_attach_child(parent_b, a, "PB-A", &child_of_bds, 1224 BDRV_CHILD_COW, &error_abort); 1225 1226 bdrv_ref(a); 1227 bdrv_attach_child(parent_a, a, "PA-A", 1228 by_parent_cb ? &child_of_bds : &detach_by_driver_cb_class, 1229 BDRV_CHILD_DATA, &error_abort); 1230 1231 g_assert_cmpint(parent_a->refcnt, ==, 1); 1232 g_assert_cmpint(parent_b->refcnt, ==, 1); 1233 g_assert_cmpint(a->refcnt, ==, 3); 1234 g_assert_cmpint(b->refcnt, ==, 2); 1235 g_assert_cmpint(c->refcnt, ==, 1); 1236 1237 g_assert(QLIST_FIRST(&parent_b->children) == child_a); 1238 g_assert(QLIST_NEXT(child_a, next) == child_b); 1239 g_assert(QLIST_NEXT(child_b, next) == NULL); 1240 1241 /* Start the evil write request */ 1242 detach_by_parent_data = (struct detach_by_parent_data) { 1243 .parent_b = parent_b, 1244 .child_b = child_b, 1245 .c = c, 1246 .by_parent_cb = by_parent_cb, 1247 .detach_on_drain = true, 1248 }; 1249 acb = blk_aio_preadv(blk, 0, &qiov, 0, detach_by_parent_aio_cb, NULL); 1250 g_assert(acb != NULL); 1251 1252 /* Drain and check the expected result */ 1253 bdrv_drained_begin(parent_b); 1254 bdrv_drained_begin(a); 1255 bdrv_drained_begin(b); 1256 bdrv_drained_begin(c); 1257 1258 g_assert(detach_by_parent_data.child_c != NULL); 1259 1260 g_assert_cmpint(parent_a->refcnt, ==, 1); 1261 g_assert_cmpint(parent_b->refcnt, ==, 1); 1262 g_assert_cmpint(a->refcnt, ==, 3); 1263 g_assert_cmpint(b->refcnt, ==, 1); 1264 g_assert_cmpint(c->refcnt, ==, 2); 1265 1266 g_assert(QLIST_FIRST(&parent_b->children) == detach_by_parent_data.child_c); 1267 g_assert(QLIST_NEXT(detach_by_parent_data.child_c, next) == child_a); 1268 g_assert(QLIST_NEXT(child_a, next) == NULL); 1269 1270 g_assert_cmpint(parent_a->quiesce_counter, ==, 1); 1271 g_assert_cmpint(parent_b->quiesce_counter, ==, 3); 1272 g_assert_cmpint(a->quiesce_counter, ==, 1); 1273 g_assert_cmpint(b->quiesce_counter, ==, 1); 1274 g_assert_cmpint(c->quiesce_counter, ==, 1); 1275 1276 bdrv_drained_end(parent_b); 1277 bdrv_drained_end(a); 1278 bdrv_drained_end(b); 1279 bdrv_drained_end(c); 1280 1281 bdrv_unref(parent_b); 1282 blk_unref(blk); 1283 1284 g_assert_cmpint(a->refcnt, ==, 1); 1285 g_assert_cmpint(b->refcnt, ==, 1); 1286 g_assert_cmpint(c->refcnt, ==, 1); 1287 bdrv_unref(a); 1288 bdrv_unref(b); 1289 bdrv_unref(c); 1290 } 1291 1292 static void test_detach_by_parent_cb(void) 1293 { 1294 test_detach_indirect(true); 1295 } 1296 1297 static void test_detach_by_driver_cb(void) 1298 { 1299 test_detach_indirect(false); 1300 } 1301 1302 static void test_append_to_drained(void) 1303 { 1304 BlockBackend *blk; 1305 BlockDriverState *base, *overlay; 1306 BDRVTestState *base_s, *overlay_s; 1307 1308 blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); 1309 base = bdrv_new_open_driver(&bdrv_test, "base", BDRV_O_RDWR, &error_abort); 1310 base_s = base->opaque; 1311 blk_insert_bs(blk, base, &error_abort); 1312 1313 overlay = bdrv_new_open_driver(&bdrv_test, "overlay", BDRV_O_RDWR, 1314 &error_abort); 1315 overlay_s = overlay->opaque; 1316 1317 do_drain_begin(BDRV_DRAIN, base); 1318 g_assert_cmpint(base->quiesce_counter, ==, 1); 1319 g_assert_cmpint(base_s->drain_count, ==, 1); 1320 g_assert_cmpint(base->in_flight, ==, 0); 1321 1322 bdrv_append(overlay, base, &error_abort); 1323 g_assert_cmpint(base->in_flight, ==, 0); 1324 g_assert_cmpint(overlay->in_flight, ==, 0); 1325 1326 g_assert_cmpint(base->quiesce_counter, ==, 1); 1327 g_assert_cmpint(base_s->drain_count, ==, 1); 1328 g_assert_cmpint(overlay->quiesce_counter, ==, 1); 1329 g_assert_cmpint(overlay_s->drain_count, ==, 1); 1330 1331 do_drain_end(BDRV_DRAIN, base); 1332 1333 g_assert_cmpint(base->quiesce_counter, ==, 0); 1334 g_assert_cmpint(base_s->drain_count, ==, 0); 1335 g_assert_cmpint(overlay->quiesce_counter, ==, 0); 1336 g_assert_cmpint(overlay_s->drain_count, ==, 0); 1337 1338 bdrv_unref(overlay); 1339 bdrv_unref(base); 1340 blk_unref(blk); 1341 } 1342 1343 static void test_set_aio_context(void) 1344 { 1345 BlockDriverState *bs; 1346 IOThread *a = iothread_new(); 1347 IOThread *b = iothread_new(); 1348 AioContext *ctx_a = iothread_get_aio_context(a); 1349 AioContext *ctx_b = iothread_get_aio_context(b); 1350 1351 bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR, 1352 &error_abort); 1353 1354 bdrv_drained_begin(bs); 1355 bdrv_try_change_aio_context(bs, ctx_a, NULL, &error_abort); 1356 1357 aio_context_acquire(ctx_a); 1358 bdrv_drained_end(bs); 1359 1360 bdrv_drained_begin(bs); 1361 bdrv_try_change_aio_context(bs, ctx_b, NULL, &error_abort); 1362 aio_context_release(ctx_a); 1363 aio_context_acquire(ctx_b); 1364 bdrv_try_change_aio_context(bs, qemu_get_aio_context(), NULL, &error_abort); 1365 aio_context_release(ctx_b); 1366 bdrv_drained_end(bs); 1367 1368 bdrv_unref(bs); 1369 iothread_join(a); 1370 iothread_join(b); 1371 } 1372 1373 1374 typedef struct TestDropBackingBlockJob { 1375 BlockJob common; 1376 bool should_complete; 1377 bool *did_complete; 1378 BlockDriverState *detach_also; 1379 BlockDriverState *bs; 1380 } TestDropBackingBlockJob; 1381 1382 static int coroutine_fn test_drop_backing_job_run(Job *job, Error **errp) 1383 { 1384 TestDropBackingBlockJob *s = 1385 container_of(job, TestDropBackingBlockJob, common.job); 1386 1387 while (!s->should_complete) { 1388 job_sleep_ns(job, 0); 1389 } 1390 1391 return 0; 1392 } 1393 1394 static void test_drop_backing_job_commit(Job *job) 1395 { 1396 TestDropBackingBlockJob *s = 1397 container_of(job, TestDropBackingBlockJob, common.job); 1398 1399 bdrv_set_backing_hd(s->bs, NULL, &error_abort); 1400 bdrv_set_backing_hd(s->detach_also, NULL, &error_abort); 1401 1402 *s->did_complete = true; 1403 } 1404 1405 static const BlockJobDriver test_drop_backing_job_driver = { 1406 .job_driver = { 1407 .instance_size = sizeof(TestDropBackingBlockJob), 1408 .free = block_job_free, 1409 .user_resume = block_job_user_resume, 1410 .run = test_drop_backing_job_run, 1411 .commit = test_drop_backing_job_commit, 1412 } 1413 }; 1414 1415 /** 1416 * Creates a child node with three parent nodes on it, and then runs a 1417 * block job on the final one, parent-node-2. 1418 * 1419 * The job is then asked to complete before a section where the child 1420 * is drained. 1421 * 1422 * Ending this section will undrain the child's parents, first 1423 * parent-node-2, then parent-node-1, then parent-node-0 -- the parent 1424 * list is in reverse order of how they were added. Ending the drain 1425 * on parent-node-2 will resume the job, thus completing it and 1426 * scheduling job_exit(). 1427 * 1428 * Ending the drain on parent-node-1 will poll the AioContext, which 1429 * lets job_exit() and thus test_drop_backing_job_commit() run. That 1430 * function first removes the child as parent-node-2's backing file. 1431 * 1432 * In old (and buggy) implementations, there are two problems with 1433 * that: 1434 * (A) bdrv_drain_invoke() polls for every node that leaves the 1435 * drained section. This means that job_exit() is scheduled 1436 * before the child has left the drained section. Its 1437 * quiesce_counter is therefore still 1 when it is removed from 1438 * parent-node-2. 1439 * 1440 * (B) bdrv_replace_child_noperm() calls drained_end() on the old 1441 * child's parents as many times as the child is quiesced. This 1442 * means it will call drained_end() on parent-node-2 once. 1443 * Because parent-node-2 is no longer quiesced at this point, this 1444 * will fail. 1445 * 1446 * bdrv_replace_child_noperm() therefore must call drained_end() on 1447 * the parent only if it really is still drained because the child is 1448 * drained. 1449 * 1450 * If removing child from parent-node-2 was successful (as it should 1451 * be), test_drop_backing_job_commit() will then also remove the child 1452 * from parent-node-0. 1453 * 1454 * With an old version of our drain infrastructure ((A) above), that 1455 * resulted in the following flow: 1456 * 1457 * 1. child attempts to leave its drained section. The call recurses 1458 * to its parents. 1459 * 1460 * 2. parent-node-2 leaves the drained section. Polling in 1461 * bdrv_drain_invoke() will schedule job_exit(). 1462 * 1463 * 3. parent-node-1 leaves the drained section. Polling in 1464 * bdrv_drain_invoke() will run job_exit(), thus disconnecting 1465 * parent-node-0 from the child node. 1466 * 1467 * 4. bdrv_parent_drained_end() uses a QLIST_FOREACH_SAFE() loop to 1468 * iterate over the parents. Thus, it now accesses the BdrvChild 1469 * object that used to connect parent-node-0 and the child node. 1470 * However, that object no longer exists, so it accesses a dangling 1471 * pointer. 1472 * 1473 * The solution is to only poll once when running a bdrv_drained_end() 1474 * operation, specifically at the end when all drained_end() 1475 * operations for all involved nodes have been scheduled. 1476 * Note that this also solves (A) above, thus hiding (B). 1477 */ 1478 static void test_blockjob_commit_by_drained_end(void) 1479 { 1480 BlockDriverState *bs_child, *bs_parents[3]; 1481 TestDropBackingBlockJob *job; 1482 bool job_has_completed = false; 1483 int i; 1484 1485 bs_child = bdrv_new_open_driver(&bdrv_test, "child-node", BDRV_O_RDWR, 1486 &error_abort); 1487 1488 for (i = 0; i < 3; i++) { 1489 char name[32]; 1490 snprintf(name, sizeof(name), "parent-node-%i", i); 1491 bs_parents[i] = bdrv_new_open_driver(&bdrv_test, name, BDRV_O_RDWR, 1492 &error_abort); 1493 bdrv_set_backing_hd(bs_parents[i], bs_child, &error_abort); 1494 } 1495 1496 job = block_job_create("job", &test_drop_backing_job_driver, NULL, 1497 bs_parents[2], 0, BLK_PERM_ALL, 0, 0, NULL, NULL, 1498 &error_abort); 1499 job->bs = bs_parents[2]; 1500 1501 job->detach_also = bs_parents[0]; 1502 job->did_complete = &job_has_completed; 1503 1504 job_start(&job->common.job); 1505 1506 job->should_complete = true; 1507 bdrv_drained_begin(bs_child); 1508 g_assert(!job_has_completed); 1509 bdrv_drained_end(bs_child); 1510 aio_poll(qemu_get_aio_context(), false); 1511 g_assert(job_has_completed); 1512 1513 bdrv_unref(bs_parents[0]); 1514 bdrv_unref(bs_parents[1]); 1515 bdrv_unref(bs_parents[2]); 1516 bdrv_unref(bs_child); 1517 } 1518 1519 1520 typedef struct TestSimpleBlockJob { 1521 BlockJob common; 1522 bool should_complete; 1523 bool *did_complete; 1524 } TestSimpleBlockJob; 1525 1526 static int coroutine_fn test_simple_job_run(Job *job, Error **errp) 1527 { 1528 TestSimpleBlockJob *s = container_of(job, TestSimpleBlockJob, common.job); 1529 1530 while (!s->should_complete) { 1531 job_sleep_ns(job, 0); 1532 } 1533 1534 return 0; 1535 } 1536 1537 static void test_simple_job_clean(Job *job) 1538 { 1539 TestSimpleBlockJob *s = container_of(job, TestSimpleBlockJob, common.job); 1540 *s->did_complete = true; 1541 } 1542 1543 static const BlockJobDriver test_simple_job_driver = { 1544 .job_driver = { 1545 .instance_size = sizeof(TestSimpleBlockJob), 1546 .free = block_job_free, 1547 .user_resume = block_job_user_resume, 1548 .run = test_simple_job_run, 1549 .clean = test_simple_job_clean, 1550 }, 1551 }; 1552 1553 static int drop_intermediate_poll_update_filename(BdrvChild *child, 1554 BlockDriverState *new_base, 1555 const char *filename, 1556 Error **errp) 1557 { 1558 /* 1559 * We are free to poll here, which may change the block graph, if 1560 * it is not drained. 1561 */ 1562 1563 /* If the job is not drained: Complete it, schedule job_exit() */ 1564 aio_poll(qemu_get_current_aio_context(), false); 1565 /* If the job is not drained: Run job_exit(), finish the job */ 1566 aio_poll(qemu_get_current_aio_context(), false); 1567 1568 return 0; 1569 } 1570 1571 /** 1572 * Test a poll in the midst of bdrv_drop_intermediate(). 1573 * 1574 * bdrv_drop_intermediate() calls BdrvChildClass.update_filename(), 1575 * which can yield or poll. This may lead to graph changes, unless 1576 * the whole subtree in question is drained. 1577 * 1578 * We test this on the following graph: 1579 * 1580 * Job 1581 * 1582 * | 1583 * job-node 1584 * | 1585 * v 1586 * 1587 * job-node 1588 * 1589 * | 1590 * backing 1591 * | 1592 * v 1593 * 1594 * node-2 --chain--> node-1 --chain--> node-0 1595 * 1596 * We drop node-1 with bdrv_drop_intermediate(top=node-1, base=node-0). 1597 * 1598 * This first updates node-2's backing filename by invoking 1599 * drop_intermediate_poll_update_filename(), which polls twice. This 1600 * causes the job to finish, which in turns causes the job-node to be 1601 * deleted. 1602 * 1603 * bdrv_drop_intermediate() uses a QLIST_FOREACH_SAFE() loop, so it 1604 * already has a pointer to the BdrvChild edge between job-node and 1605 * node-1. When it tries to handle that edge, we probably get a 1606 * segmentation fault because the object no longer exists. 1607 * 1608 * 1609 * The solution is for bdrv_drop_intermediate() to drain top's 1610 * subtree. This prevents graph changes from happening just because 1611 * BdrvChildClass.update_filename() yields or polls. Thus, the block 1612 * job is paused during that drained section and must finish before or 1613 * after. 1614 * 1615 * (In addition, bdrv_replace_child() must keep the job paused.) 1616 */ 1617 static void test_drop_intermediate_poll(void) 1618 { 1619 static BdrvChildClass chain_child_class; 1620 BlockDriverState *chain[3]; 1621 TestSimpleBlockJob *job; 1622 BlockDriverState *job_node; 1623 bool job_has_completed = false; 1624 int i; 1625 int ret; 1626 1627 chain_child_class = child_of_bds; 1628 chain_child_class.update_filename = drop_intermediate_poll_update_filename; 1629 1630 for (i = 0; i < 3; i++) { 1631 char name[32]; 1632 snprintf(name, 32, "node-%i", i); 1633 1634 chain[i] = bdrv_new_open_driver(&bdrv_test, name, 0, &error_abort); 1635 } 1636 1637 job_node = bdrv_new_open_driver(&bdrv_test, "job-node", BDRV_O_RDWR, 1638 &error_abort); 1639 bdrv_set_backing_hd(job_node, chain[1], &error_abort); 1640 1641 /* 1642 * Establish the chain last, so the chain links are the first 1643 * elements in the BDS.parents lists 1644 */ 1645 for (i = 0; i < 3; i++) { 1646 if (i) { 1647 /* Takes the reference to chain[i - 1] */ 1648 bdrv_attach_child(chain[i], chain[i - 1], "chain", 1649 &chain_child_class, BDRV_CHILD_COW, &error_abort); 1650 } 1651 } 1652 1653 job = block_job_create("job", &test_simple_job_driver, NULL, job_node, 1654 0, BLK_PERM_ALL, 0, 0, NULL, NULL, &error_abort); 1655 1656 /* The job has a reference now */ 1657 bdrv_unref(job_node); 1658 1659 job->did_complete = &job_has_completed; 1660 1661 job_start(&job->common.job); 1662 job->should_complete = true; 1663 1664 g_assert(!job_has_completed); 1665 ret = bdrv_drop_intermediate(chain[1], chain[0], NULL); 1666 aio_poll(qemu_get_aio_context(), false); 1667 g_assert(ret == 0); 1668 g_assert(job_has_completed); 1669 1670 bdrv_unref(chain[2]); 1671 } 1672 1673 1674 typedef struct BDRVReplaceTestState { 1675 bool setup_completed; 1676 bool was_drained; 1677 bool was_undrained; 1678 bool has_read; 1679 1680 int drain_count; 1681 1682 bool yield_before_read; 1683 Coroutine *io_co; 1684 Coroutine *drain_co; 1685 } BDRVReplaceTestState; 1686 1687 static void bdrv_replace_test_close(BlockDriverState *bs) 1688 { 1689 } 1690 1691 /** 1692 * If @bs has a backing file: 1693 * Yield if .yield_before_read is true (and wait for drain_begin to 1694 * wake us up). 1695 * Forward the read to bs->backing. Set .has_read to true. 1696 * If drain_begin has woken us, wake it in turn. 1697 * 1698 * Otherwise: 1699 * Set .has_read to true and return success. 1700 */ 1701 static int coroutine_fn bdrv_replace_test_co_preadv(BlockDriverState *bs, 1702 int64_t offset, 1703 int64_t bytes, 1704 QEMUIOVector *qiov, 1705 BdrvRequestFlags flags) 1706 { 1707 BDRVReplaceTestState *s = bs->opaque; 1708 1709 if (bs->backing) { 1710 int ret; 1711 1712 g_assert(!s->drain_count); 1713 1714 s->io_co = qemu_coroutine_self(); 1715 if (s->yield_before_read) { 1716 s->yield_before_read = false; 1717 qemu_coroutine_yield(); 1718 } 1719 s->io_co = NULL; 1720 1721 ret = bdrv_co_preadv(bs->backing, offset, bytes, qiov, 0); 1722 s->has_read = true; 1723 1724 /* Wake up drain_co if it runs */ 1725 if (s->drain_co) { 1726 aio_co_wake(s->drain_co); 1727 } 1728 1729 return ret; 1730 } 1731 1732 s->has_read = true; 1733 return 0; 1734 } 1735 1736 static void coroutine_fn bdrv_replace_test_drain_co(void *opaque) 1737 { 1738 BlockDriverState *bs = opaque; 1739 BDRVReplaceTestState *s = bs->opaque; 1740 1741 /* Keep waking io_co up until it is done */ 1742 while (s->io_co) { 1743 aio_co_wake(s->io_co); 1744 s->io_co = NULL; 1745 qemu_coroutine_yield(); 1746 } 1747 s->drain_co = NULL; 1748 bdrv_dec_in_flight(bs); 1749 } 1750 1751 /** 1752 * If .drain_count is 0, wake up .io_co if there is one; and set 1753 * .was_drained. 1754 * Increment .drain_count. 1755 */ 1756 static void bdrv_replace_test_drain_begin(BlockDriverState *bs) 1757 { 1758 BDRVReplaceTestState *s = bs->opaque; 1759 1760 if (!s->setup_completed) { 1761 return; 1762 } 1763 1764 if (!s->drain_count) { 1765 s->drain_co = qemu_coroutine_create(bdrv_replace_test_drain_co, bs); 1766 bdrv_inc_in_flight(bs); 1767 aio_co_enter(bdrv_get_aio_context(bs), s->drain_co); 1768 s->was_drained = true; 1769 } 1770 s->drain_count++; 1771 } 1772 1773 static void coroutine_fn bdrv_replace_test_read_entry(void *opaque) 1774 { 1775 BlockDriverState *bs = opaque; 1776 char data; 1777 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, &data, 1); 1778 int ret; 1779 1780 /* Queue a read request post-drain */ 1781 ret = bdrv_replace_test_co_preadv(bs, 0, 1, &qiov, 0); 1782 g_assert(ret >= 0); 1783 bdrv_dec_in_flight(bs); 1784 } 1785 1786 /** 1787 * Reduce .drain_count, set .was_undrained once it reaches 0. 1788 * If .drain_count reaches 0 and the node has a backing file, issue a 1789 * read request. 1790 */ 1791 static void bdrv_replace_test_drain_end(BlockDriverState *bs) 1792 { 1793 BDRVReplaceTestState *s = bs->opaque; 1794 1795 if (!s->setup_completed) { 1796 return; 1797 } 1798 1799 g_assert(s->drain_count > 0); 1800 if (!--s->drain_count) { 1801 s->was_undrained = true; 1802 1803 if (bs->backing) { 1804 Coroutine *co = qemu_coroutine_create(bdrv_replace_test_read_entry, 1805 bs); 1806 bdrv_inc_in_flight(bs); 1807 aio_co_enter(bdrv_get_aio_context(bs), co); 1808 } 1809 } 1810 } 1811 1812 static BlockDriver bdrv_replace_test = { 1813 .format_name = "replace_test", 1814 .instance_size = sizeof(BDRVReplaceTestState), 1815 .supports_backing = true, 1816 1817 .bdrv_close = bdrv_replace_test_close, 1818 .bdrv_co_preadv = bdrv_replace_test_co_preadv, 1819 1820 .bdrv_drain_begin = bdrv_replace_test_drain_begin, 1821 .bdrv_drain_end = bdrv_replace_test_drain_end, 1822 1823 .bdrv_child_perm = bdrv_default_perms, 1824 }; 1825 1826 static void coroutine_fn test_replace_child_mid_drain_read_co(void *opaque) 1827 { 1828 int ret; 1829 char data; 1830 1831 ret = blk_co_pread(opaque, 0, 1, &data, 0); 1832 g_assert(ret >= 0); 1833 } 1834 1835 /** 1836 * We test two things: 1837 * (1) bdrv_replace_child_noperm() must not undrain the parent if both 1838 * children are drained. 1839 * (2) bdrv_replace_child_noperm() must never flush I/O requests to a 1840 * drained child. If the old child is drained, it must flush I/O 1841 * requests after the new one has been attached. If the new child 1842 * is drained, it must flush I/O requests before the old one is 1843 * detached. 1844 * 1845 * To do so, we create one parent node and two child nodes; then 1846 * attach one of the children (old_child_bs) to the parent, then 1847 * drain both old_child_bs and new_child_bs according to 1848 * old_drain_count and new_drain_count, respectively, and finally 1849 * we invoke bdrv_replace_node() to replace old_child_bs by 1850 * new_child_bs. 1851 * 1852 * The test block driver we use here (bdrv_replace_test) has a read 1853 * function that: 1854 * - For the parent node, can optionally yield, and then forwards the 1855 * read to bdrv_preadv(), 1856 * - For the child node, just returns immediately. 1857 * 1858 * If the read yields, the drain_begin function will wake it up. 1859 * 1860 * The drain_end function issues a read on the parent once it is fully 1861 * undrained (which simulates requests starting to come in again). 1862 */ 1863 static void do_test_replace_child_mid_drain(int old_drain_count, 1864 int new_drain_count) 1865 { 1866 BlockBackend *parent_blk; 1867 BlockDriverState *parent_bs; 1868 BlockDriverState *old_child_bs, *new_child_bs; 1869 BDRVReplaceTestState *parent_s; 1870 BDRVReplaceTestState *old_child_s, *new_child_s; 1871 Coroutine *io_co; 1872 int i; 1873 1874 parent_bs = bdrv_new_open_driver(&bdrv_replace_test, "parent", 0, 1875 &error_abort); 1876 parent_s = parent_bs->opaque; 1877 1878 parent_blk = blk_new(qemu_get_aio_context(), 1879 BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL); 1880 blk_insert_bs(parent_blk, parent_bs, &error_abort); 1881 1882 old_child_bs = bdrv_new_open_driver(&bdrv_replace_test, "old-child", 0, 1883 &error_abort); 1884 new_child_bs = bdrv_new_open_driver(&bdrv_replace_test, "new-child", 0, 1885 &error_abort); 1886 old_child_s = old_child_bs->opaque; 1887 new_child_s = new_child_bs->opaque; 1888 1889 /* So that we can read something */ 1890 parent_bs->total_sectors = 1; 1891 old_child_bs->total_sectors = 1; 1892 new_child_bs->total_sectors = 1; 1893 1894 bdrv_ref(old_child_bs); 1895 bdrv_attach_child(parent_bs, old_child_bs, "child", &child_of_bds, 1896 BDRV_CHILD_COW, &error_abort); 1897 parent_s->setup_completed = true; 1898 1899 for (i = 0; i < old_drain_count; i++) { 1900 bdrv_drained_begin(old_child_bs); 1901 } 1902 for (i = 0; i < new_drain_count; i++) { 1903 bdrv_drained_begin(new_child_bs); 1904 } 1905 1906 if (!old_drain_count) { 1907 /* 1908 * Start a read operation that will yield, so it will not 1909 * complete before the node is drained. 1910 */ 1911 parent_s->yield_before_read = true; 1912 io_co = qemu_coroutine_create(test_replace_child_mid_drain_read_co, 1913 parent_blk); 1914 qemu_coroutine_enter(io_co); 1915 } 1916 1917 /* If we have started a read operation, it should have yielded */ 1918 g_assert(!parent_s->has_read); 1919 1920 /* Reset drained status so we can see what bdrv_replace_node() does */ 1921 parent_s->was_drained = false; 1922 parent_s->was_undrained = false; 1923 1924 g_assert(parent_bs->quiesce_counter == old_drain_count); 1925 bdrv_replace_node(old_child_bs, new_child_bs, &error_abort); 1926 g_assert(parent_bs->quiesce_counter == new_drain_count); 1927 1928 if (!old_drain_count && !new_drain_count) { 1929 /* 1930 * From undrained to undrained drains and undrains the parent, 1931 * because bdrv_replace_node() contains a drained section for 1932 * @old_child_bs. 1933 */ 1934 g_assert(parent_s->was_drained && parent_s->was_undrained); 1935 } else if (!old_drain_count && new_drain_count) { 1936 /* 1937 * From undrained to drained should drain the parent and keep 1938 * it that way. 1939 */ 1940 g_assert(parent_s->was_drained && !parent_s->was_undrained); 1941 } else if (old_drain_count && !new_drain_count) { 1942 /* 1943 * From drained to undrained should undrain the parent and 1944 * keep it that way. 1945 */ 1946 g_assert(!parent_s->was_drained && parent_s->was_undrained); 1947 } else /* if (old_drain_count && new_drain_count) */ { 1948 /* 1949 * From drained to drained must not undrain the parent at any 1950 * point 1951 */ 1952 g_assert(!parent_s->was_drained && !parent_s->was_undrained); 1953 } 1954 1955 if (!old_drain_count || !new_drain_count) { 1956 /* 1957 * If !old_drain_count, we have started a read request before 1958 * bdrv_replace_node(). If !new_drain_count, the parent must 1959 * have been undrained at some point, and 1960 * bdrv_replace_test_co_drain_end() starts a read request 1961 * then. 1962 */ 1963 g_assert(parent_s->has_read); 1964 } else { 1965 /* 1966 * If the parent was never undrained, there is no way to start 1967 * a read request. 1968 */ 1969 g_assert(!parent_s->has_read); 1970 } 1971 1972 /* A drained child must have not received any request */ 1973 g_assert(!(old_drain_count && old_child_s->has_read)); 1974 g_assert(!(new_drain_count && new_child_s->has_read)); 1975 1976 for (i = 0; i < new_drain_count; i++) { 1977 bdrv_drained_end(new_child_bs); 1978 } 1979 for (i = 0; i < old_drain_count; i++) { 1980 bdrv_drained_end(old_child_bs); 1981 } 1982 1983 /* 1984 * By now, bdrv_replace_test_co_drain_end() must have been called 1985 * at some point while the new child was attached to the parent. 1986 */ 1987 g_assert(parent_s->has_read); 1988 g_assert(new_child_s->has_read); 1989 1990 blk_unref(parent_blk); 1991 bdrv_unref(parent_bs); 1992 bdrv_unref(old_child_bs); 1993 bdrv_unref(new_child_bs); 1994 } 1995 1996 static void test_replace_child_mid_drain(void) 1997 { 1998 int old_drain_count, new_drain_count; 1999 2000 for (old_drain_count = 0; old_drain_count < 2; old_drain_count++) { 2001 for (new_drain_count = 0; new_drain_count < 2; new_drain_count++) { 2002 do_test_replace_child_mid_drain(old_drain_count, new_drain_count); 2003 } 2004 } 2005 } 2006 2007 int main(int argc, char **argv) 2008 { 2009 int ret; 2010 2011 bdrv_init(); 2012 qemu_init_main_loop(&error_abort); 2013 2014 g_test_init(&argc, &argv, NULL); 2015 qemu_event_init(&done_event, false); 2016 2017 g_test_add_func("/bdrv-drain/driver-cb/drain_all", test_drv_cb_drain_all); 2018 g_test_add_func("/bdrv-drain/driver-cb/drain", test_drv_cb_drain); 2019 2020 g_test_add_func("/bdrv-drain/driver-cb/co/drain_all", 2021 test_drv_cb_co_drain_all); 2022 g_test_add_func("/bdrv-drain/driver-cb/co/drain", test_drv_cb_co_drain); 2023 2024 g_test_add_func("/bdrv-drain/quiesce/drain_all", test_quiesce_drain_all); 2025 g_test_add_func("/bdrv-drain/quiesce/drain", test_quiesce_drain); 2026 2027 g_test_add_func("/bdrv-drain/quiesce/co/drain_all", 2028 test_quiesce_co_drain_all); 2029 g_test_add_func("/bdrv-drain/quiesce/co/drain", test_quiesce_co_drain); 2030 2031 g_test_add_func("/bdrv-drain/nested", test_nested); 2032 2033 g_test_add_func("/bdrv-drain/graph-change/drain_all", 2034 test_graph_change_drain_all); 2035 2036 g_test_add_func("/bdrv-drain/iothread/drain_all", test_iothread_drain_all); 2037 g_test_add_func("/bdrv-drain/iothread/drain", test_iothread_drain); 2038 2039 g_test_add_func("/bdrv-drain/blockjob/drain_all", test_blockjob_drain_all); 2040 g_test_add_func("/bdrv-drain/blockjob/drain", test_blockjob_drain); 2041 2042 g_test_add_func("/bdrv-drain/blockjob/error/drain_all", 2043 test_blockjob_error_drain_all); 2044 g_test_add_func("/bdrv-drain/blockjob/error/drain", 2045 test_blockjob_error_drain); 2046 2047 g_test_add_func("/bdrv-drain/blockjob/iothread/drain_all", 2048 test_blockjob_iothread_drain_all); 2049 g_test_add_func("/bdrv-drain/blockjob/iothread/drain", 2050 test_blockjob_iothread_drain); 2051 2052 g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain_all", 2053 test_blockjob_iothread_error_drain_all); 2054 g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain", 2055 test_blockjob_iothread_error_drain); 2056 2057 g_test_add_func("/bdrv-drain/deletion/drain", test_delete_by_drain); 2058 g_test_add_func("/bdrv-drain/detach/drain_all", test_detach_by_drain_all); 2059 g_test_add_func("/bdrv-drain/detach/drain", test_detach_by_drain); 2060 g_test_add_func("/bdrv-drain/detach/parent_cb", test_detach_by_parent_cb); 2061 g_test_add_func("/bdrv-drain/detach/driver_cb", test_detach_by_driver_cb); 2062 2063 g_test_add_func("/bdrv-drain/attach/drain", test_append_to_drained); 2064 2065 g_test_add_func("/bdrv-drain/set_aio_context", test_set_aio_context); 2066 2067 g_test_add_func("/bdrv-drain/blockjob/commit_by_drained_end", 2068 test_blockjob_commit_by_drained_end); 2069 2070 g_test_add_func("/bdrv-drain/bdrv_drop_intermediate/poll", 2071 test_drop_intermediate_poll); 2072 2073 g_test_add_func("/bdrv-drain/replace_child/mid-drain", 2074 test_replace_child_mid_drain); 2075 2076 ret = g_test_run(); 2077 qemu_event_destroy(&done_event); 2078 return ret; 2079 } 2080