trap signals for "-serial mon:stdio"
[qemu.git] / block-migration.c
1 /*
2 * QEMU live block migration
3 *
4 * Copyright IBM, Corp. 2009
5 *
6 * Authors:
7 * Liran Schour <lirans@il.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 * Contributions after 2012-01-13 are licensed under the terms of the
13 * GNU GPL, version 2 or (at your option) any later version.
14 */
15
16 #include "qemu-common.h"
17 #include "block/block_int.h"
18 #include "hw/hw.h"
19 #include "qemu/queue.h"
20 #include "qemu/timer.h"
21 #include "migration/block.h"
22 #include "migration/migration.h"
23 #include "sysemu/blockdev.h"
24 #include <assert.h>
25
26 #define BLOCK_SIZE (1 << 20)
27 #define BDRV_SECTORS_PER_DIRTY_CHUNK (BLOCK_SIZE >> BDRV_SECTOR_BITS)
28
29 #define BLK_MIG_FLAG_DEVICE_BLOCK 0x01
30 #define BLK_MIG_FLAG_EOS 0x02
31 #define BLK_MIG_FLAG_PROGRESS 0x04
32
33 #define MAX_IS_ALLOCATED_SEARCH 65536
34
35 //#define DEBUG_BLK_MIGRATION
36
37 #ifdef DEBUG_BLK_MIGRATION
38 #define DPRINTF(fmt, ...) \
39 do { printf("blk_migration: " fmt, ## __VA_ARGS__); } while (0)
40 #else
41 #define DPRINTF(fmt, ...) \
42 do { } while (0)
43 #endif
44
45 typedef struct BlkMigDevState {
46 /* Written during setup phase. Can be read without a lock. */
47 BlockDriverState *bs;
48 int shared_base;
49 int64_t total_sectors;
50 QSIMPLEQ_ENTRY(BlkMigDevState) entry;
51
52 /* Only used by migration thread. Does not need a lock. */
53 int bulk_completed;
54 int64_t cur_sector;
55 int64_t cur_dirty;
56
57 /* Protected by block migration lock. */
58 unsigned long *aio_bitmap;
59 int64_t completed_sectors;
60 } BlkMigDevState;
61
62 typedef struct BlkMigBlock {
63 /* Only used by migration thread. */
64 uint8_t *buf;
65 BlkMigDevState *bmds;
66 int64_t sector;
67 int nr_sectors;
68 struct iovec iov;
69 QEMUIOVector qiov;
70 BlockDriverAIOCB *aiocb;
71
72 /* Protected by block migration lock. */
73 int ret;
74 QSIMPLEQ_ENTRY(BlkMigBlock) entry;
75 } BlkMigBlock;
76
77 typedef struct BlkMigState {
78 /* Written during setup phase. Can be read without a lock. */
79 int blk_enable;
80 int shared_base;
81 QSIMPLEQ_HEAD(bmds_list, BlkMigDevState) bmds_list;
82 int64_t total_sector_sum;
83
84 /* Protected by lock. */
85 QSIMPLEQ_HEAD(blk_list, BlkMigBlock) blk_list;
86 int submitted;
87 int read_done;
88
89 /* Only used by migration thread. Does not need a lock. */
90 int transferred;
91 int prev_progress;
92 int bulk_completed;
93
94 /* Lock must be taken _inside_ the iothread lock. */
95 QemuMutex lock;
96 } BlkMigState;
97
98 static BlkMigState block_mig_state;
99
100 static void blk_mig_lock(void)
101 {
102 qemu_mutex_lock(&block_mig_state.lock);
103 }
104
105 static void blk_mig_unlock(void)
106 {
107 qemu_mutex_unlock(&block_mig_state.lock);
108 }
109
110 /* Must run outside of the iothread lock during the bulk phase,
111 * or the VM will stall.
112 */
113
114 static void blk_send(QEMUFile *f, BlkMigBlock * blk)
115 {
116 int len;
117
118 /* sector number and flags */
119 qemu_put_be64(f, (blk->sector << BDRV_SECTOR_BITS)
120 | BLK_MIG_FLAG_DEVICE_BLOCK);
121
122 /* device name */
123 len = strlen(blk->bmds->bs->device_name);
124 qemu_put_byte(f, len);
125 qemu_put_buffer(f, (uint8_t *)blk->bmds->bs->device_name, len);
126
127 qemu_put_buffer(f, blk->buf, BLOCK_SIZE);
128 }
129
130 int blk_mig_active(void)
131 {
132 return !QSIMPLEQ_EMPTY(&block_mig_state.bmds_list);
133 }
134
135 uint64_t blk_mig_bytes_transferred(void)
136 {
137 BlkMigDevState *bmds;
138 uint64_t sum = 0;
139
140 blk_mig_lock();
141 QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
142 sum += bmds->completed_sectors;
143 }
144 blk_mig_unlock();
145 return sum << BDRV_SECTOR_BITS;
146 }
147
148 uint64_t blk_mig_bytes_remaining(void)
149 {
150 return blk_mig_bytes_total() - blk_mig_bytes_transferred();
151 }
152
153 uint64_t blk_mig_bytes_total(void)
154 {
155 BlkMigDevState *bmds;
156 uint64_t sum = 0;
157
158 QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
159 sum += bmds->total_sectors;
160 }
161 return sum << BDRV_SECTOR_BITS;
162 }
163
164
165 /* Called with migration lock held. */
166
167 static int bmds_aio_inflight(BlkMigDevState *bmds, int64_t sector)
168 {
169 int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
170
171 if ((sector << BDRV_SECTOR_BITS) < bdrv_getlength(bmds->bs)) {
172 return !!(bmds->aio_bitmap[chunk / (sizeof(unsigned long) * 8)] &
173 (1UL << (chunk % (sizeof(unsigned long) * 8))));
174 } else {
175 return 0;
176 }
177 }
178
179 /* Called with migration lock held. */
180
181 static void bmds_set_aio_inflight(BlkMigDevState *bmds, int64_t sector_num,
182 int nb_sectors, int set)
183 {
184 int64_t start, end;
185 unsigned long val, idx, bit;
186
187 start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK;
188 end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK;
189
190 for (; start <= end; start++) {
191 idx = start / (sizeof(unsigned long) * 8);
192 bit = start % (sizeof(unsigned long) * 8);
193 val = bmds->aio_bitmap[idx];
194 if (set) {
195 val |= 1UL << bit;
196 } else {
197 val &= ~(1UL << bit);
198 }
199 bmds->aio_bitmap[idx] = val;
200 }
201 }
202
203 static void alloc_aio_bitmap(BlkMigDevState *bmds)
204 {
205 BlockDriverState *bs = bmds->bs;
206 int64_t bitmap_size;
207
208 bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) +
209 BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1;
210 bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8;
211
212 bmds->aio_bitmap = g_malloc0(bitmap_size);
213 }
214
215 /* Never hold migration lock when yielding to the main loop! */
216
217 static void blk_mig_read_cb(void *opaque, int ret)
218 {
219 BlkMigBlock *blk = opaque;
220
221 blk_mig_lock();
222 blk->ret = ret;
223
224 QSIMPLEQ_INSERT_TAIL(&block_mig_state.blk_list, blk, entry);
225 bmds_set_aio_inflight(blk->bmds, blk->sector, blk->nr_sectors, 0);
226
227 block_mig_state.submitted--;
228 block_mig_state.read_done++;
229 assert(block_mig_state.submitted >= 0);
230 blk_mig_unlock();
231 }
232
233 /* Called with no lock taken. */
234
235 static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
236 {
237 int64_t total_sectors = bmds->total_sectors;
238 int64_t cur_sector = bmds->cur_sector;
239 BlockDriverState *bs = bmds->bs;
240 BlkMigBlock *blk;
241 int nr_sectors;
242
243 if (bmds->shared_base) {
244 qemu_mutex_lock_iothread();
245 while (cur_sector < total_sectors &&
246 !bdrv_is_allocated(bs, cur_sector, MAX_IS_ALLOCATED_SEARCH,
247 &nr_sectors)) {
248 cur_sector += nr_sectors;
249 }
250 qemu_mutex_unlock_iothread();
251 }
252
253 if (cur_sector >= total_sectors) {
254 bmds->cur_sector = bmds->completed_sectors = total_sectors;
255 return 1;
256 }
257
258 bmds->completed_sectors = cur_sector;
259
260 cur_sector &= ~((int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK - 1);
261
262 /* we are going to transfer a full block even if it is not allocated */
263 nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
264
265 if (total_sectors - cur_sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
266 nr_sectors = total_sectors - cur_sector;
267 }
268
269 blk = g_malloc(sizeof(BlkMigBlock));
270 blk->buf = g_malloc(BLOCK_SIZE);
271 blk->bmds = bmds;
272 blk->sector = cur_sector;
273 blk->nr_sectors = nr_sectors;
274
275 blk->iov.iov_base = blk->buf;
276 blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
277 qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
278
279 blk_mig_lock();
280 block_mig_state.submitted++;
281 blk_mig_unlock();
282
283 qemu_mutex_lock_iothread();
284 blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov,
285 nr_sectors, blk_mig_read_cb, blk);
286
287 bdrv_reset_dirty(bs, cur_sector, nr_sectors);
288 qemu_mutex_unlock_iothread();
289
290 bmds->cur_sector = cur_sector + nr_sectors;
291 return (bmds->cur_sector >= total_sectors);
292 }
293
294 /* Called with iothread lock taken. */
295
296 static void set_dirty_tracking(int enable)
297 {
298 BlkMigDevState *bmds;
299
300 QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
301 bdrv_set_dirty_tracking(bmds->bs, enable ? BLOCK_SIZE : 0);
302 }
303 }
304
305 static void init_blk_migration_it(void *opaque, BlockDriverState *bs)
306 {
307 BlkMigDevState *bmds;
308 int64_t sectors;
309
310 if (!bdrv_is_read_only(bs)) {
311 sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
312 if (sectors <= 0) {
313 return;
314 }
315
316 bmds = g_malloc0(sizeof(BlkMigDevState));
317 bmds->bs = bs;
318 bmds->bulk_completed = 0;
319 bmds->total_sectors = sectors;
320 bmds->completed_sectors = 0;
321 bmds->shared_base = block_mig_state.shared_base;
322 alloc_aio_bitmap(bmds);
323 drive_get_ref(drive_get_by_blockdev(bs));
324 bdrv_set_in_use(bs, 1);
325
326 block_mig_state.total_sector_sum += sectors;
327
328 if (bmds->shared_base) {
329 DPRINTF("Start migration for %s with shared base image\n",
330 bs->device_name);
331 } else {
332 DPRINTF("Start full migration for %s\n", bs->device_name);
333 }
334
335 QSIMPLEQ_INSERT_TAIL(&block_mig_state.bmds_list, bmds, entry);
336 }
337 }
338
339 static void init_blk_migration(QEMUFile *f)
340 {
341 block_mig_state.submitted = 0;
342 block_mig_state.read_done = 0;
343 block_mig_state.transferred = 0;
344 block_mig_state.total_sector_sum = 0;
345 block_mig_state.prev_progress = -1;
346 block_mig_state.bulk_completed = 0;
347
348 bdrv_iterate(init_blk_migration_it, NULL);
349 }
350
351 /* Called with no lock taken. */
352
353 static int blk_mig_save_bulked_block(QEMUFile *f)
354 {
355 int64_t completed_sector_sum = 0;
356 BlkMigDevState *bmds;
357 int progress;
358 int ret = 0;
359
360 QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
361 if (bmds->bulk_completed == 0) {
362 if (mig_save_device_bulk(f, bmds) == 1) {
363 /* completed bulk section for this device */
364 bmds->bulk_completed = 1;
365 }
366 completed_sector_sum += bmds->completed_sectors;
367 ret = 1;
368 break;
369 } else {
370 completed_sector_sum += bmds->completed_sectors;
371 }
372 }
373
374 if (block_mig_state.total_sector_sum != 0) {
375 progress = completed_sector_sum * 100 /
376 block_mig_state.total_sector_sum;
377 } else {
378 progress = 100;
379 }
380 if (progress != block_mig_state.prev_progress) {
381 block_mig_state.prev_progress = progress;
382 qemu_put_be64(f, (progress << BDRV_SECTOR_BITS)
383 | BLK_MIG_FLAG_PROGRESS);
384 DPRINTF("Completed %d %%\r", progress);
385 }
386
387 return ret;
388 }
389
390 static void blk_mig_reset_dirty_cursor(void)
391 {
392 BlkMigDevState *bmds;
393
394 QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
395 bmds->cur_dirty = 0;
396 }
397 }
398
399 /* Called with iothread lock taken. */
400
401 static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
402 int is_async)
403 {
404 BlkMigBlock *blk;
405 int64_t total_sectors = bmds->total_sectors;
406 int64_t sector;
407 int nr_sectors;
408 int ret = -EIO;
409
410 for (sector = bmds->cur_dirty; sector < bmds->total_sectors;) {
411 blk_mig_lock();
412 if (bmds_aio_inflight(bmds, sector)) {
413 blk_mig_unlock();
414 bdrv_drain_all();
415 } else {
416 blk_mig_unlock();
417 }
418 if (bdrv_get_dirty(bmds->bs, sector)) {
419
420 if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
421 nr_sectors = total_sectors - sector;
422 } else {
423 nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
424 }
425 blk = g_malloc(sizeof(BlkMigBlock));
426 blk->buf = g_malloc(BLOCK_SIZE);
427 blk->bmds = bmds;
428 blk->sector = sector;
429 blk->nr_sectors = nr_sectors;
430
431 if (is_async) {
432 blk->iov.iov_base = blk->buf;
433 blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
434 qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
435
436 blk->aiocb = bdrv_aio_readv(bmds->bs, sector, &blk->qiov,
437 nr_sectors, blk_mig_read_cb, blk);
438
439 blk_mig_lock();
440 block_mig_state.submitted++;
441 bmds_set_aio_inflight(bmds, sector, nr_sectors, 1);
442 blk_mig_unlock();
443 } else {
444 ret = bdrv_read(bmds->bs, sector, blk->buf, nr_sectors);
445 if (ret < 0) {
446 goto error;
447 }
448 blk_send(f, blk);
449
450 g_free(blk->buf);
451 g_free(blk);
452 }
453
454 bdrv_reset_dirty(bmds->bs, sector, nr_sectors);
455 break;
456 }
457 sector += BDRV_SECTORS_PER_DIRTY_CHUNK;
458 bmds->cur_dirty = sector;
459 }
460
461 return (bmds->cur_dirty >= bmds->total_sectors);
462
463 error:
464 DPRINTF("Error reading sector %" PRId64 "\n", sector);
465 g_free(blk->buf);
466 g_free(blk);
467 return ret;
468 }
469
470 /* Called with iothread lock taken.
471 *
472 * return value:
473 * 0: too much data for max_downtime
474 * 1: few enough data for max_downtime
475 */
476 static int blk_mig_save_dirty_block(QEMUFile *f, int is_async)
477 {
478 BlkMigDevState *bmds;
479 int ret = 1;
480
481 QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
482 ret = mig_save_device_dirty(f, bmds, is_async);
483 if (ret <= 0) {
484 break;
485 }
486 }
487
488 return ret;
489 }
490
491 /* Called with no locks taken. */
492
493 static int flush_blks(QEMUFile *f)
494 {
495 BlkMigBlock *blk;
496 int ret = 0;
497
498 DPRINTF("%s Enter submitted %d read_done %d transferred %d\n",
499 __FUNCTION__, block_mig_state.submitted, block_mig_state.read_done,
500 block_mig_state.transferred);
501
502 blk_mig_lock();
503 while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) {
504 if (qemu_file_rate_limit(f)) {
505 break;
506 }
507 if (blk->ret < 0) {
508 ret = blk->ret;
509 break;
510 }
511
512 QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry);
513 blk_mig_unlock();
514 blk_send(f, blk);
515 blk_mig_lock();
516
517 g_free(blk->buf);
518 g_free(blk);
519
520 block_mig_state.read_done--;
521 block_mig_state.transferred++;
522 assert(block_mig_state.read_done >= 0);
523 }
524 blk_mig_unlock();
525
526 DPRINTF("%s Exit submitted %d read_done %d transferred %d\n", __FUNCTION__,
527 block_mig_state.submitted, block_mig_state.read_done,
528 block_mig_state.transferred);
529 return ret;
530 }
531
532 /* Called with iothread lock taken. */
533
534 static int64_t get_remaining_dirty(void)
535 {
536 BlkMigDevState *bmds;
537 int64_t dirty = 0;
538
539 QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
540 dirty += bdrv_get_dirty_count(bmds->bs);
541 }
542
543 return dirty << BDRV_SECTOR_BITS;
544 }
545
546 /* Called with iothread lock taken. */
547
548 static void blk_mig_cleanup(void)
549 {
550 BlkMigDevState *bmds;
551 BlkMigBlock *blk;
552
553 bdrv_drain_all();
554
555 set_dirty_tracking(0);
556
557 blk_mig_lock();
558 while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
559 QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
560 bdrv_set_in_use(bmds->bs, 0);
561 drive_put_ref(drive_get_by_blockdev(bmds->bs));
562 g_free(bmds->aio_bitmap);
563 g_free(bmds);
564 }
565
566 while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) {
567 QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry);
568 g_free(blk->buf);
569 g_free(blk);
570 }
571 blk_mig_unlock();
572 }
573
574 static void block_migration_cancel(void *opaque)
575 {
576 blk_mig_cleanup();
577 }
578
579 static int block_save_setup(QEMUFile *f, void *opaque)
580 {
581 int ret;
582
583 DPRINTF("Enter save live setup submitted %d transferred %d\n",
584 block_mig_state.submitted, block_mig_state.transferred);
585
586 qemu_mutex_lock_iothread();
587 init_blk_migration(f);
588
589 /* start track dirty blocks */
590 set_dirty_tracking(1);
591 qemu_mutex_unlock_iothread();
592
593 ret = flush_blks(f);
594 blk_mig_reset_dirty_cursor();
595 qemu_put_be64(f, BLK_MIG_FLAG_EOS);
596
597 return ret;
598 }
599
600 static int block_save_iterate(QEMUFile *f, void *opaque)
601 {
602 int ret;
603 int64_t last_ftell = qemu_ftell(f);
604
605 DPRINTF("Enter save live iterate submitted %d transferred %d\n",
606 block_mig_state.submitted, block_mig_state.transferred);
607
608 ret = flush_blks(f);
609 if (ret) {
610 return ret;
611 }
612
613 blk_mig_reset_dirty_cursor();
614
615 /* control the rate of transfer */
616 blk_mig_lock();
617 while ((block_mig_state.submitted +
618 block_mig_state.read_done) * BLOCK_SIZE <
619 qemu_file_get_rate_limit(f)) {
620 blk_mig_unlock();
621 if (block_mig_state.bulk_completed == 0) {
622 /* first finish the bulk phase */
623 if (blk_mig_save_bulked_block(f) == 0) {
624 /* finished saving bulk on all devices */
625 block_mig_state.bulk_completed = 1;
626 }
627 ret = 0;
628 } else {
629 /* Always called with iothread lock taken for
630 * simplicity, block_save_complete also calls it.
631 */
632 qemu_mutex_lock_iothread();
633 ret = blk_mig_save_dirty_block(f, 1);
634 qemu_mutex_unlock_iothread();
635 }
636 if (ret < 0) {
637 return ret;
638 }
639 blk_mig_lock();
640 if (ret != 0) {
641 /* no more dirty blocks */
642 break;
643 }
644 }
645 blk_mig_unlock();
646
647 ret = flush_blks(f);
648 if (ret) {
649 return ret;
650 }
651
652 qemu_put_be64(f, BLK_MIG_FLAG_EOS);
653 return qemu_ftell(f) - last_ftell;
654 }
655
656 /* Called with iothread lock taken. */
657
658 static int block_save_complete(QEMUFile *f, void *opaque)
659 {
660 int ret;
661
662 DPRINTF("Enter save live complete submitted %d transferred %d\n",
663 block_mig_state.submitted, block_mig_state.transferred);
664
665 ret = flush_blks(f);
666 if (ret) {
667 return ret;
668 }
669
670 blk_mig_reset_dirty_cursor();
671
672 /* we know for sure that save bulk is completed and
673 all async read completed */
674 blk_mig_lock();
675 assert(block_mig_state.submitted == 0);
676 blk_mig_unlock();
677
678 do {
679 ret = blk_mig_save_dirty_block(f, 0);
680 if (ret < 0) {
681 return ret;
682 }
683 } while (ret == 0);
684
685 /* report completion */
686 qemu_put_be64(f, (100 << BDRV_SECTOR_BITS) | BLK_MIG_FLAG_PROGRESS);
687
688 DPRINTF("Block migration completed\n");
689
690 qemu_put_be64(f, BLK_MIG_FLAG_EOS);
691
692 blk_mig_cleanup();
693 return 0;
694 }
695
696 static uint64_t block_save_pending(QEMUFile *f, void *opaque, uint64_t max_size)
697 {
698 /* Estimate pending number of bytes to send */
699 uint64_t pending;
700
701 qemu_mutex_lock_iothread();
702 blk_mig_lock();
703 pending = get_remaining_dirty() +
704 block_mig_state.submitted * BLOCK_SIZE +
705 block_mig_state.read_done * BLOCK_SIZE;
706
707 /* Report at least one block pending during bulk phase */
708 if (pending == 0 && !block_mig_state.bulk_completed) {
709 pending = BLOCK_SIZE;
710 }
711 blk_mig_unlock();
712 qemu_mutex_unlock_iothread();
713
714 DPRINTF("Enter save live pending %" PRIu64 "\n", pending);
715 return pending;
716 }
717
718 static int block_load(QEMUFile *f, void *opaque, int version_id)
719 {
720 static int banner_printed;
721 int len, flags;
722 char device_name[256];
723 int64_t addr;
724 BlockDriverState *bs, *bs_prev = NULL;
725 uint8_t *buf;
726 int64_t total_sectors = 0;
727 int nr_sectors;
728 int ret;
729
730 do {
731 addr = qemu_get_be64(f);
732
733 flags = addr & ~BDRV_SECTOR_MASK;
734 addr >>= BDRV_SECTOR_BITS;
735
736 if (flags & BLK_MIG_FLAG_DEVICE_BLOCK) {
737 /* get device name */
738 len = qemu_get_byte(f);
739 qemu_get_buffer(f, (uint8_t *)device_name, len);
740 device_name[len] = '\0';
741
742 bs = bdrv_find(device_name);
743 if (!bs) {
744 fprintf(stderr, "Error unknown block device %s\n",
745 device_name);
746 return -EINVAL;
747 }
748
749 if (bs != bs_prev) {
750 bs_prev = bs;
751 total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
752 if (total_sectors <= 0) {
753 error_report("Error getting length of block device %s",
754 device_name);
755 return -EINVAL;
756 }
757 }
758
759 if (total_sectors - addr < BDRV_SECTORS_PER_DIRTY_CHUNK) {
760 nr_sectors = total_sectors - addr;
761 } else {
762 nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
763 }
764
765 buf = g_malloc(BLOCK_SIZE);
766
767 qemu_get_buffer(f, buf, BLOCK_SIZE);
768 ret = bdrv_write(bs, addr, buf, nr_sectors);
769
770 g_free(buf);
771 if (ret < 0) {
772 return ret;
773 }
774 } else if (flags & BLK_MIG_FLAG_PROGRESS) {
775 if (!banner_printed) {
776 printf("Receiving block device images\n");
777 banner_printed = 1;
778 }
779 printf("Completed %d %%%c", (int)addr,
780 (addr == 100) ? '\n' : '\r');
781 fflush(stdout);
782 } else if (!(flags & BLK_MIG_FLAG_EOS)) {
783 fprintf(stderr, "Unknown block migration flags: %#x\n", flags);
784 return -EINVAL;
785 }
786 ret = qemu_file_get_error(f);
787 if (ret != 0) {
788 return ret;
789 }
790 } while (!(flags & BLK_MIG_FLAG_EOS));
791
792 return 0;
793 }
794
795 static void block_set_params(const MigrationParams *params, void *opaque)
796 {
797 block_mig_state.blk_enable = params->blk;
798 block_mig_state.shared_base = params->shared;
799
800 /* shared base means that blk_enable = 1 */
801 block_mig_state.blk_enable |= params->shared;
802 }
803
804 static bool block_is_active(void *opaque)
805 {
806 return block_mig_state.blk_enable == 1;
807 }
808
809 SaveVMHandlers savevm_block_handlers = {
810 .set_params = block_set_params,
811 .save_live_setup = block_save_setup,
812 .save_live_iterate = block_save_iterate,
813 .save_live_complete = block_save_complete,
814 .save_live_pending = block_save_pending,
815 .load_state = block_load,
816 .cancel = block_migration_cancel,
817 .is_active = block_is_active,
818 };
819
820 void blk_mig_init(void)
821 {
822 QSIMPLEQ_INIT(&block_mig_state.bmds_list);
823 QSIMPLEQ_INIT(&block_mig_state.blk_list);
824 qemu_mutex_init(&block_mig_state.lock);
825
826 register_savevm_live(NULL, "block", 0, 1, &savevm_block_handlers,
827 &block_mig_state);
828 }