2 * QEMU live block migration
4 * Copyright IBM, Corp. 2009
7 * Liran Schour <lirans@il.ibm.com>
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
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.
16 #include "qemu-common.h"
17 #include "block/block.h"
18 #include "qemu/error-report.h"
19 #include "qemu/main-loop.h"
21 #include "qemu/queue.h"
22 #include "qemu/timer.h"
23 #include "migration/block.h"
24 #include "migration/migration.h"
25 #include "sysemu/blockdev.h"
26 #include "sysemu/block-backend.h"
29 #define BLOCK_SIZE (1 << 20)
30 #define BDRV_SECTORS_PER_DIRTY_CHUNK (BLOCK_SIZE >> BDRV_SECTOR_BITS)
32 #define BLK_MIG_FLAG_DEVICE_BLOCK 0x01
33 #define BLK_MIG_FLAG_EOS 0x02
34 #define BLK_MIG_FLAG_PROGRESS 0x04
35 #define BLK_MIG_FLAG_ZERO_BLOCK 0x08
37 #define MAX_IS_ALLOCATED_SEARCH 65536
39 #define MAX_INFLIGHT_IO 512
41 //#define DEBUG_BLK_MIGRATION
43 #ifdef DEBUG_BLK_MIGRATION
44 #define DPRINTF(fmt, ...) \
45 do { printf("blk_migration: " fmt, ## __VA_ARGS__); } while (0)
47 #define DPRINTF(fmt, ...) \
51 typedef struct BlkMigDevState
{
52 /* Written during setup phase. Can be read without a lock. */
55 int64_t total_sectors
;
56 QSIMPLEQ_ENTRY(BlkMigDevState
) entry
;
58 /* Only used by migration thread. Does not need a lock. */
63 /* Protected by block migration lock. */
64 unsigned long *aio_bitmap
;
65 int64_t completed_sectors
;
66 BdrvDirtyBitmap
*dirty_bitmap
;
70 typedef struct BlkMigBlock
{
71 /* Only used by migration thread. */
80 /* Protected by block migration lock. */
82 QSIMPLEQ_ENTRY(BlkMigBlock
) entry
;
85 typedef struct BlkMigState
{
86 /* Written during setup phase. Can be read without a lock. */
89 QSIMPLEQ_HEAD(bmds_list
, BlkMigDevState
) bmds_list
;
90 int64_t total_sector_sum
;
93 /* Protected by lock. */
94 QSIMPLEQ_HEAD(blk_list
, BlkMigBlock
) blk_list
;
98 /* Only used by migration thread. Does not need a lock. */
103 /* Lock must be taken _inside_ the iothread lock. */
107 static BlkMigState block_mig_state
;
109 static void blk_mig_lock(void)
111 qemu_mutex_lock(&block_mig_state
.lock
);
114 static void blk_mig_unlock(void)
116 qemu_mutex_unlock(&block_mig_state
.lock
);
119 /* Must run outside of the iothread lock during the bulk phase,
120 * or the VM will stall.
123 static void blk_send(QEMUFile
*f
, BlkMigBlock
* blk
)
126 uint64_t flags
= BLK_MIG_FLAG_DEVICE_BLOCK
;
128 if (block_mig_state
.zero_blocks
&&
129 buffer_is_zero(blk
->buf
, BLOCK_SIZE
)) {
130 flags
|= BLK_MIG_FLAG_ZERO_BLOCK
;
133 /* sector number and flags */
134 qemu_put_be64(f
, (blk
->sector
<< BDRV_SECTOR_BITS
)
138 len
= strlen(bdrv_get_device_name(blk
->bmds
->bs
));
139 qemu_put_byte(f
, len
);
140 qemu_put_buffer(f
, (uint8_t *)bdrv_get_device_name(blk
->bmds
->bs
), len
);
142 /* if a block is zero we need to flush here since the network
143 * bandwidth is now a lot higher than the storage device bandwidth.
144 * thus if we queue zero blocks we slow down the migration */
145 if (flags
& BLK_MIG_FLAG_ZERO_BLOCK
) {
150 qemu_put_buffer(f
, blk
->buf
, BLOCK_SIZE
);
153 int blk_mig_active(void)
155 return !QSIMPLEQ_EMPTY(&block_mig_state
.bmds_list
);
158 uint64_t blk_mig_bytes_transferred(void)
160 BlkMigDevState
*bmds
;
164 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
165 sum
+= bmds
->completed_sectors
;
168 return sum
<< BDRV_SECTOR_BITS
;
171 uint64_t blk_mig_bytes_remaining(void)
173 return blk_mig_bytes_total() - blk_mig_bytes_transferred();
176 uint64_t blk_mig_bytes_total(void)
178 BlkMigDevState
*bmds
;
181 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
182 sum
+= bmds
->total_sectors
;
184 return sum
<< BDRV_SECTOR_BITS
;
188 /* Called with migration lock held. */
190 static int bmds_aio_inflight(BlkMigDevState
*bmds
, int64_t sector
)
192 int64_t chunk
= sector
/ (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK
;
194 if (sector
< bdrv_nb_sectors(bmds
->bs
)) {
195 return !!(bmds
->aio_bitmap
[chunk
/ (sizeof(unsigned long) * 8)] &
196 (1UL << (chunk
% (sizeof(unsigned long) * 8))));
202 /* Called with migration lock held. */
204 static void bmds_set_aio_inflight(BlkMigDevState
*bmds
, int64_t sector_num
,
205 int nb_sectors
, int set
)
208 unsigned long val
, idx
, bit
;
210 start
= sector_num
/ BDRV_SECTORS_PER_DIRTY_CHUNK
;
211 end
= (sector_num
+ nb_sectors
- 1) / BDRV_SECTORS_PER_DIRTY_CHUNK
;
213 for (; start
<= end
; start
++) {
214 idx
= start
/ (sizeof(unsigned long) * 8);
215 bit
= start
% (sizeof(unsigned long) * 8);
216 val
= bmds
->aio_bitmap
[idx
];
220 val
&= ~(1UL << bit
);
222 bmds
->aio_bitmap
[idx
] = val
;
226 static void alloc_aio_bitmap(BlkMigDevState
*bmds
)
228 BlockDriverState
*bs
= bmds
->bs
;
231 bitmap_size
= bdrv_nb_sectors(bs
) + BDRV_SECTORS_PER_DIRTY_CHUNK
* 8 - 1;
232 bitmap_size
/= BDRV_SECTORS_PER_DIRTY_CHUNK
* 8;
234 bmds
->aio_bitmap
= g_malloc0(bitmap_size
);
237 /* Never hold migration lock when yielding to the main loop! */
239 static void blk_mig_read_cb(void *opaque
, int ret
)
241 BlkMigBlock
*blk
= opaque
;
246 QSIMPLEQ_INSERT_TAIL(&block_mig_state
.blk_list
, blk
, entry
);
247 bmds_set_aio_inflight(blk
->bmds
, blk
->sector
, blk
->nr_sectors
, 0);
249 block_mig_state
.submitted
--;
250 block_mig_state
.read_done
++;
251 assert(block_mig_state
.submitted
>= 0);
255 /* Called with no lock taken. */
257 static int mig_save_device_bulk(QEMUFile
*f
, BlkMigDevState
*bmds
)
259 int64_t total_sectors
= bmds
->total_sectors
;
260 int64_t cur_sector
= bmds
->cur_sector
;
261 BlockDriverState
*bs
= bmds
->bs
;
265 if (bmds
->shared_base
) {
266 qemu_mutex_lock_iothread();
267 while (cur_sector
< total_sectors
&&
268 !bdrv_is_allocated(bs
, cur_sector
, MAX_IS_ALLOCATED_SEARCH
,
270 cur_sector
+= nr_sectors
;
272 qemu_mutex_unlock_iothread();
275 if (cur_sector
>= total_sectors
) {
276 bmds
->cur_sector
= bmds
->completed_sectors
= total_sectors
;
280 bmds
->completed_sectors
= cur_sector
;
282 cur_sector
&= ~((int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK
- 1);
284 /* we are going to transfer a full block even if it is not allocated */
285 nr_sectors
= BDRV_SECTORS_PER_DIRTY_CHUNK
;
287 if (total_sectors
- cur_sector
< BDRV_SECTORS_PER_DIRTY_CHUNK
) {
288 nr_sectors
= total_sectors
- cur_sector
;
291 blk
= g_new(BlkMigBlock
, 1);
292 blk
->buf
= g_malloc(BLOCK_SIZE
);
294 blk
->sector
= cur_sector
;
295 blk
->nr_sectors
= nr_sectors
;
297 blk
->iov
.iov_base
= blk
->buf
;
298 blk
->iov
.iov_len
= nr_sectors
* BDRV_SECTOR_SIZE
;
299 qemu_iovec_init_external(&blk
->qiov
, &blk
->iov
, 1);
302 block_mig_state
.submitted
++;
305 qemu_mutex_lock_iothread();
306 blk
->aiocb
= bdrv_aio_readv(bs
, cur_sector
, &blk
->qiov
,
307 nr_sectors
, blk_mig_read_cb
, blk
);
309 bdrv_reset_dirty_bitmap(bmds
->dirty_bitmap
, cur_sector
, nr_sectors
);
310 qemu_mutex_unlock_iothread();
312 bmds
->cur_sector
= cur_sector
+ nr_sectors
;
313 return (bmds
->cur_sector
>= total_sectors
);
316 /* Called with iothread lock taken. */
318 static int set_dirty_tracking(void)
320 BlkMigDevState
*bmds
;
323 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
324 bmds
->dirty_bitmap
= bdrv_create_dirty_bitmap(bmds
->bs
, BLOCK_SIZE
,
326 if (!bmds
->dirty_bitmap
) {
334 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
335 if (bmds
->dirty_bitmap
) {
336 bdrv_release_dirty_bitmap(bmds
->bs
, bmds
->dirty_bitmap
);
342 static void unset_dirty_tracking(void)
344 BlkMigDevState
*bmds
;
346 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
347 bdrv_release_dirty_bitmap(bmds
->bs
, bmds
->dirty_bitmap
);
351 static void init_blk_migration(QEMUFile
*f
)
353 BlockDriverState
*bs
;
354 BlkMigDevState
*bmds
;
357 block_mig_state
.submitted
= 0;
358 block_mig_state
.read_done
= 0;
359 block_mig_state
.transferred
= 0;
360 block_mig_state
.total_sector_sum
= 0;
361 block_mig_state
.prev_progress
= -1;
362 block_mig_state
.bulk_completed
= 0;
363 block_mig_state
.zero_blocks
= migrate_zero_blocks();
365 for (bs
= bdrv_next(NULL
); bs
; bs
= bdrv_next(bs
)) {
366 if (bdrv_is_read_only(bs
)) {
370 sectors
= bdrv_nb_sectors(bs
);
375 bmds
= g_new0(BlkMigDevState
, 1);
377 bmds
->bulk_completed
= 0;
378 bmds
->total_sectors
= sectors
;
379 bmds
->completed_sectors
= 0;
380 bmds
->shared_base
= block_mig_state
.shared_base
;
381 alloc_aio_bitmap(bmds
);
382 error_setg(&bmds
->blocker
, "block device is in use by migration");
383 bdrv_op_block_all(bs
, bmds
->blocker
);
386 block_mig_state
.total_sector_sum
+= sectors
;
388 if (bmds
->shared_base
) {
389 DPRINTF("Start migration for %s with shared base image\n",
390 bdrv_get_device_name(bs
));
392 DPRINTF("Start full migration for %s\n", bdrv_get_device_name(bs
));
395 QSIMPLEQ_INSERT_TAIL(&block_mig_state
.bmds_list
, bmds
, entry
);
399 /* Called with no lock taken. */
401 static int blk_mig_save_bulked_block(QEMUFile
*f
)
403 int64_t completed_sector_sum
= 0;
404 BlkMigDevState
*bmds
;
408 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
409 if (bmds
->bulk_completed
== 0) {
410 if (mig_save_device_bulk(f
, bmds
) == 1) {
411 /* completed bulk section for this device */
412 bmds
->bulk_completed
= 1;
414 completed_sector_sum
+= bmds
->completed_sectors
;
418 completed_sector_sum
+= bmds
->completed_sectors
;
422 if (block_mig_state
.total_sector_sum
!= 0) {
423 progress
= completed_sector_sum
* 100 /
424 block_mig_state
.total_sector_sum
;
428 if (progress
!= block_mig_state
.prev_progress
) {
429 block_mig_state
.prev_progress
= progress
;
430 qemu_put_be64(f
, (progress
<< BDRV_SECTOR_BITS
)
431 | BLK_MIG_FLAG_PROGRESS
);
432 DPRINTF("Completed %d %%\r", progress
);
438 static void blk_mig_reset_dirty_cursor(void)
440 BlkMigDevState
*bmds
;
442 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
447 /* Called with iothread lock taken. */
449 static int mig_save_device_dirty(QEMUFile
*f
, BlkMigDevState
*bmds
,
453 int64_t total_sectors
= bmds
->total_sectors
;
458 for (sector
= bmds
->cur_dirty
; sector
< bmds
->total_sectors
;) {
460 if (bmds_aio_inflight(bmds
, sector
)) {
462 bdrv_drain(bmds
->bs
);
466 if (bdrv_get_dirty(bmds
->bs
, bmds
->dirty_bitmap
, sector
)) {
468 if (total_sectors
- sector
< BDRV_SECTORS_PER_DIRTY_CHUNK
) {
469 nr_sectors
= total_sectors
- sector
;
471 nr_sectors
= BDRV_SECTORS_PER_DIRTY_CHUNK
;
473 blk
= g_new(BlkMigBlock
, 1);
474 blk
->buf
= g_malloc(BLOCK_SIZE
);
476 blk
->sector
= sector
;
477 blk
->nr_sectors
= nr_sectors
;
480 blk
->iov
.iov_base
= blk
->buf
;
481 blk
->iov
.iov_len
= nr_sectors
* BDRV_SECTOR_SIZE
;
482 qemu_iovec_init_external(&blk
->qiov
, &blk
->iov
, 1);
484 blk
->aiocb
= bdrv_aio_readv(bmds
->bs
, sector
, &blk
->qiov
,
485 nr_sectors
, blk_mig_read_cb
, blk
);
488 block_mig_state
.submitted
++;
489 bmds_set_aio_inflight(bmds
, sector
, nr_sectors
, 1);
492 ret
= bdrv_read(bmds
->bs
, sector
, blk
->buf
, nr_sectors
);
502 bdrv_reset_dirty_bitmap(bmds
->dirty_bitmap
, sector
, nr_sectors
);
505 sector
+= BDRV_SECTORS_PER_DIRTY_CHUNK
;
506 bmds
->cur_dirty
= sector
;
509 return (bmds
->cur_dirty
>= bmds
->total_sectors
);
512 DPRINTF("Error reading sector %" PRId64
"\n", sector
);
518 /* Called with iothread lock taken.
521 * 0: too much data for max_downtime
522 * 1: few enough data for max_downtime
524 static int blk_mig_save_dirty_block(QEMUFile
*f
, int is_async
)
526 BlkMigDevState
*bmds
;
529 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
530 ret
= mig_save_device_dirty(f
, bmds
, is_async
);
539 /* Called with no locks taken. */
541 static int flush_blks(QEMUFile
*f
)
546 DPRINTF("%s Enter submitted %d read_done %d transferred %d\n",
547 __FUNCTION__
, block_mig_state
.submitted
, block_mig_state
.read_done
,
548 block_mig_state
.transferred
);
551 while ((blk
= QSIMPLEQ_FIRST(&block_mig_state
.blk_list
)) != NULL
) {
552 if (qemu_file_rate_limit(f
)) {
560 QSIMPLEQ_REMOVE_HEAD(&block_mig_state
.blk_list
, entry
);
568 block_mig_state
.read_done
--;
569 block_mig_state
.transferred
++;
570 assert(block_mig_state
.read_done
>= 0);
574 DPRINTF("%s Exit submitted %d read_done %d transferred %d\n", __FUNCTION__
,
575 block_mig_state
.submitted
, block_mig_state
.read_done
,
576 block_mig_state
.transferred
);
580 /* Called with iothread lock taken. */
582 static int64_t get_remaining_dirty(void)
584 BlkMigDevState
*bmds
;
587 QSIMPLEQ_FOREACH(bmds
, &block_mig_state
.bmds_list
, entry
) {
588 dirty
+= bdrv_get_dirty_count(bmds
->dirty_bitmap
);
591 return dirty
<< BDRV_SECTOR_BITS
;
594 /* Called with iothread lock taken. */
596 static void block_migration_cleanup(void *opaque
)
598 BlkMigDevState
*bmds
;
603 unset_dirty_tracking();
606 while ((bmds
= QSIMPLEQ_FIRST(&block_mig_state
.bmds_list
)) != NULL
) {
607 QSIMPLEQ_REMOVE_HEAD(&block_mig_state
.bmds_list
, entry
);
608 bdrv_op_unblock_all(bmds
->bs
, bmds
->blocker
);
609 error_free(bmds
->blocker
);
610 bdrv_unref(bmds
->bs
);
611 g_free(bmds
->aio_bitmap
);
615 while ((blk
= QSIMPLEQ_FIRST(&block_mig_state
.blk_list
)) != NULL
) {
616 QSIMPLEQ_REMOVE_HEAD(&block_mig_state
.blk_list
, entry
);
623 static int block_save_setup(QEMUFile
*f
, void *opaque
)
627 DPRINTF("Enter save live setup submitted %d transferred %d\n",
628 block_mig_state
.submitted
, block_mig_state
.transferred
);
630 qemu_mutex_lock_iothread();
631 init_blk_migration(f
);
633 /* start track dirty blocks */
634 ret
= set_dirty_tracking();
637 qemu_mutex_unlock_iothread();
641 qemu_mutex_unlock_iothread();
644 blk_mig_reset_dirty_cursor();
645 qemu_put_be64(f
, BLK_MIG_FLAG_EOS
);
650 static int block_save_iterate(QEMUFile
*f
, void *opaque
)
653 int64_t last_ftell
= qemu_ftell(f
);
656 DPRINTF("Enter save live iterate submitted %d transferred %d\n",
657 block_mig_state
.submitted
, block_mig_state
.transferred
);
664 blk_mig_reset_dirty_cursor();
666 /* control the rate of transfer */
668 while ((block_mig_state
.submitted
+
669 block_mig_state
.read_done
) * BLOCK_SIZE
<
670 qemu_file_get_rate_limit(f
) &&
671 (block_mig_state
.submitted
+
672 block_mig_state
.read_done
) <
675 if (block_mig_state
.bulk_completed
== 0) {
676 /* first finish the bulk phase */
677 if (blk_mig_save_bulked_block(f
) == 0) {
678 /* finished saving bulk on all devices */
679 block_mig_state
.bulk_completed
= 1;
683 /* Always called with iothread lock taken for
684 * simplicity, block_save_complete also calls it.
686 qemu_mutex_lock_iothread();
687 ret
= blk_mig_save_dirty_block(f
, 1);
688 qemu_mutex_unlock_iothread();
695 /* no more dirty blocks */
706 qemu_put_be64(f
, BLK_MIG_FLAG_EOS
);
707 delta_ftell
= qemu_ftell(f
) - last_ftell
;
708 if (delta_ftell
> 0) {
710 } else if (delta_ftell
< 0) {
717 /* Called with iothread lock taken. */
719 static int block_save_complete(QEMUFile
*f
, void *opaque
)
723 DPRINTF("Enter save live complete submitted %d transferred %d\n",
724 block_mig_state
.submitted
, block_mig_state
.transferred
);
731 blk_mig_reset_dirty_cursor();
733 /* we know for sure that save bulk is completed and
734 all async read completed */
736 assert(block_mig_state
.submitted
== 0);
740 ret
= blk_mig_save_dirty_block(f
, 0);
746 /* report completion */
747 qemu_put_be64(f
, (100 << BDRV_SECTOR_BITS
) | BLK_MIG_FLAG_PROGRESS
);
749 DPRINTF("Block migration completed\n");
751 qemu_put_be64(f
, BLK_MIG_FLAG_EOS
);
756 static void block_save_pending(QEMUFile
*f
, void *opaque
, uint64_t max_size
,
757 uint64_t *non_postcopiable_pending
,
758 uint64_t *postcopiable_pending
)
760 /* Estimate pending number of bytes to send */
763 qemu_mutex_lock_iothread();
765 pending
= get_remaining_dirty() +
766 block_mig_state
.submitted
* BLOCK_SIZE
+
767 block_mig_state
.read_done
* BLOCK_SIZE
;
769 /* Report at least one block pending during bulk phase */
770 if (pending
<= max_size
&& !block_mig_state
.bulk_completed
) {
771 pending
= max_size
+ BLOCK_SIZE
;
774 qemu_mutex_unlock_iothread();
776 DPRINTF("Enter save live pending %" PRIu64
"\n", pending
);
777 /* We don't do postcopy */
778 *non_postcopiable_pending
+= pending
;
781 static int block_load(QEMUFile
*f
, void *opaque
, int version_id
)
783 static int banner_printed
;
785 char device_name
[256];
787 BlockDriverState
*bs
, *bs_prev
= NULL
;
790 int64_t total_sectors
= 0;
795 addr
= qemu_get_be64(f
);
797 flags
= addr
& ~BDRV_SECTOR_MASK
;
798 addr
>>= BDRV_SECTOR_BITS
;
800 if (flags
& BLK_MIG_FLAG_DEVICE_BLOCK
) {
801 /* get device name */
802 len
= qemu_get_byte(f
);
803 qemu_get_buffer(f
, (uint8_t *)device_name
, len
);
804 device_name
[len
] = '\0';
806 blk
= blk_by_name(device_name
);
808 fprintf(stderr
, "Error unknown block device %s\n",
814 fprintf(stderr
, "Block device %s has no medium\n",
821 total_sectors
= bdrv_nb_sectors(bs
);
822 if (total_sectors
<= 0) {
823 error_report("Error getting length of block device %s",
829 if (total_sectors
- addr
< BDRV_SECTORS_PER_DIRTY_CHUNK
) {
830 nr_sectors
= total_sectors
- addr
;
832 nr_sectors
= BDRV_SECTORS_PER_DIRTY_CHUNK
;
835 if (flags
& BLK_MIG_FLAG_ZERO_BLOCK
) {
836 ret
= bdrv_write_zeroes(bs
, addr
, nr_sectors
,
839 buf
= g_malloc(BLOCK_SIZE
);
840 qemu_get_buffer(f
, buf
, BLOCK_SIZE
);
841 ret
= bdrv_write(bs
, addr
, buf
, nr_sectors
);
848 } else if (flags
& BLK_MIG_FLAG_PROGRESS
) {
849 if (!banner_printed
) {
850 printf("Receiving block device images\n");
853 printf("Completed %d %%%c", (int)addr
,
854 (addr
== 100) ? '\n' : '\r');
856 } else if (!(flags
& BLK_MIG_FLAG_EOS
)) {
857 fprintf(stderr
, "Unknown block migration flags: %#x\n", flags
);
860 ret
= qemu_file_get_error(f
);
864 } while (!(flags
& BLK_MIG_FLAG_EOS
));
869 static void block_set_params(const MigrationParams
*params
, void *opaque
)
871 block_mig_state
.blk_enable
= params
->blk
;
872 block_mig_state
.shared_base
= params
->shared
;
874 /* shared base means that blk_enable = 1 */
875 block_mig_state
.blk_enable
|= params
->shared
;
878 static bool block_is_active(void *opaque
)
880 return block_mig_state
.blk_enable
== 1;
883 static SaveVMHandlers savevm_block_handlers
= {
884 .set_params
= block_set_params
,
885 .save_live_setup
= block_save_setup
,
886 .save_live_iterate
= block_save_iterate
,
887 .save_live_complete_precopy
= block_save_complete
,
888 .save_live_pending
= block_save_pending
,
889 .load_state
= block_load
,
890 .cleanup
= block_migration_cleanup
,
891 .is_active
= block_is_active
,
894 void blk_mig_init(void)
896 QSIMPLEQ_INIT(&block_mig_state
.bmds_list
);
897 QSIMPLEQ_INIT(&block_mig_state
.blk_list
);
898 qemu_mutex_init(&block_mig_state
.lock
);
900 register_savevm_live(NULL
, "block", 0, 1, &savevm_block_handlers
,