751 lines
23 KiB
C
751 lines
23 KiB
C
/*
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* Block dirty bitmap postcopy migration
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*
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* Copyright IBM, Corp. 2009
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* Copyright (c) 2016-2017 Virtuozzo International GmbH. All rights reserved.
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*
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* Authors:
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* Liran Schour <lirans@il.ibm.com>
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* Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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* This file is derived from migration/block.c, so it's author and IBM copyright
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* are here, although content is quite different.
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*
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* Contributions after 2012-01-13 are licensed under the terms of the
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* GNU GPL, version 2 or (at your option) any later version.
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*
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* ***
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*
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* Here postcopy migration of dirty bitmaps is realized. Only QMP-addressable
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* bitmaps are migrated.
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*
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* Bitmap migration implies creating bitmap with the same name and granularity
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* in destination QEMU. If the bitmap with the same name (for the same node)
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* already exists on destination an error will be generated.
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*
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* format of migration:
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*
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* # Header (shared for different chunk types)
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* 1, 2 or 4 bytes: flags (see qemu_{put,put}_flags)
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* [ 1 byte: node name size ] \ flags & DEVICE_NAME
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* [ n bytes: node name ] /
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* [ 1 byte: bitmap name size ] \ flags & BITMAP_NAME
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* [ n bytes: bitmap name ] /
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*
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* # Start of bitmap migration (flags & START)
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* header
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* be64: granularity
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* 1 byte: bitmap flags (corresponds to BdrvDirtyBitmap)
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* bit 0 - bitmap is enabled
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* bit 1 - bitmap is persistent
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* bit 2 - bitmap is autoloading
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* bits 3-7 - reserved, must be zero
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*
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* # Complete of bitmap migration (flags & COMPLETE)
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* header
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*
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* # Data chunk of bitmap migration
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* header
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* be64: start sector
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* be32: number of sectors
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* [ be64: buffer size ] \ ! (flags & ZEROES)
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* [ n bytes: buffer ] /
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*
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* The last chunk in stream should contain flags & EOS. The chunk may skip
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* device and/or bitmap names, assuming them to be the same with the previous
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* chunk.
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*/
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#include "qemu/osdep.h"
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#include "block/block.h"
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#include "block/block_int.h"
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#include "sysemu/block-backend.h"
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#include "qemu/main-loop.h"
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#include "qemu/error-report.h"
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#include "migration/misc.h"
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#include "migration/migration.h"
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#include "qemu-file.h"
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#include "migration/vmstate.h"
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#include "migration/register.h"
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#include "qemu/hbitmap.h"
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#include "sysemu/sysemu.h"
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#include "qemu/cutils.h"
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#include "qapi/error.h"
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#include "trace.h"
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#define CHUNK_SIZE (1 << 10)
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/* Flags occupy one, two or four bytes (Big Endian). The size is determined as
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* follows:
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* in first (most significant) byte bit 8 is clear --> one byte
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* in first byte bit 8 is set --> two or four bytes, depending on second
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* byte:
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* | in second byte bit 8 is clear --> two bytes
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* | in second byte bit 8 is set --> four bytes
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*/
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#define DIRTY_BITMAP_MIG_FLAG_EOS 0x01
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#define DIRTY_BITMAP_MIG_FLAG_ZEROES 0x02
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#define DIRTY_BITMAP_MIG_FLAG_BITMAP_NAME 0x04
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#define DIRTY_BITMAP_MIG_FLAG_DEVICE_NAME 0x08
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#define DIRTY_BITMAP_MIG_FLAG_START 0x10
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#define DIRTY_BITMAP_MIG_FLAG_COMPLETE 0x20
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#define DIRTY_BITMAP_MIG_FLAG_BITS 0x40
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#define DIRTY_BITMAP_MIG_EXTRA_FLAGS 0x80
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#define DIRTY_BITMAP_MIG_START_FLAG_ENABLED 0x01
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#define DIRTY_BITMAP_MIG_START_FLAG_PERSISTENT 0x02
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/* 0x04 was "AUTOLOAD" flags on elder versions, no it is ignored */
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#define DIRTY_BITMAP_MIG_START_FLAG_RESERVED_MASK 0xf8
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typedef struct DirtyBitmapMigBitmapState {
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/* Written during setup phase. */
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BlockDriverState *bs;
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const char *node_name;
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BdrvDirtyBitmap *bitmap;
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uint64_t total_sectors;
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uint64_t sectors_per_chunk;
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QSIMPLEQ_ENTRY(DirtyBitmapMigBitmapState) entry;
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uint8_t flags;
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/* For bulk phase. */
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bool bulk_completed;
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uint64_t cur_sector;
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} DirtyBitmapMigBitmapState;
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typedef struct DirtyBitmapMigState {
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QSIMPLEQ_HEAD(dbms_list, DirtyBitmapMigBitmapState) dbms_list;
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bool bulk_completed;
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bool no_bitmaps;
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/* for send_bitmap_bits() */
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BlockDriverState *prev_bs;
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BdrvDirtyBitmap *prev_bitmap;
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} DirtyBitmapMigState;
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typedef struct DirtyBitmapLoadState {
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uint32_t flags;
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char node_name[256];
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char bitmap_name[256];
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BlockDriverState *bs;
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BdrvDirtyBitmap *bitmap;
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} DirtyBitmapLoadState;
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static DirtyBitmapMigState dirty_bitmap_mig_state;
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typedef struct DirtyBitmapLoadBitmapState {
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BlockDriverState *bs;
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BdrvDirtyBitmap *bitmap;
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bool migrated;
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} DirtyBitmapLoadBitmapState;
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static GSList *enabled_bitmaps;
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QemuMutex finish_lock;
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void init_dirty_bitmap_incoming_migration(void)
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{
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qemu_mutex_init(&finish_lock);
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}
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static uint32_t qemu_get_bitmap_flags(QEMUFile *f)
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{
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uint8_t flags = qemu_get_byte(f);
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if (flags & DIRTY_BITMAP_MIG_EXTRA_FLAGS) {
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flags = flags << 8 | qemu_get_byte(f);
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if (flags & DIRTY_BITMAP_MIG_EXTRA_FLAGS) {
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flags = flags << 16 | qemu_get_be16(f);
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}
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}
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return flags;
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}
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static void qemu_put_bitmap_flags(QEMUFile *f, uint32_t flags)
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{
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/* The code currently do not send flags more than one byte */
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assert(!(flags & (0xffffff00 | DIRTY_BITMAP_MIG_EXTRA_FLAGS)));
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qemu_put_byte(f, flags);
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}
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static void send_bitmap_header(QEMUFile *f, DirtyBitmapMigBitmapState *dbms,
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uint32_t additional_flags)
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{
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BlockDriverState *bs = dbms->bs;
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BdrvDirtyBitmap *bitmap = dbms->bitmap;
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uint32_t flags = additional_flags;
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trace_send_bitmap_header_enter();
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if (bs != dirty_bitmap_mig_state.prev_bs) {
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dirty_bitmap_mig_state.prev_bs = bs;
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flags |= DIRTY_BITMAP_MIG_FLAG_DEVICE_NAME;
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}
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if (bitmap != dirty_bitmap_mig_state.prev_bitmap) {
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dirty_bitmap_mig_state.prev_bitmap = bitmap;
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flags |= DIRTY_BITMAP_MIG_FLAG_BITMAP_NAME;
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}
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qemu_put_bitmap_flags(f, flags);
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if (flags & DIRTY_BITMAP_MIG_FLAG_DEVICE_NAME) {
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qemu_put_counted_string(f, dbms->node_name);
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}
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if (flags & DIRTY_BITMAP_MIG_FLAG_BITMAP_NAME) {
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qemu_put_counted_string(f, bdrv_dirty_bitmap_name(bitmap));
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}
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}
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static void send_bitmap_start(QEMUFile *f, DirtyBitmapMigBitmapState *dbms)
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{
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send_bitmap_header(f, dbms, DIRTY_BITMAP_MIG_FLAG_START);
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qemu_put_be32(f, bdrv_dirty_bitmap_granularity(dbms->bitmap));
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qemu_put_byte(f, dbms->flags);
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}
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static void send_bitmap_complete(QEMUFile *f, DirtyBitmapMigBitmapState *dbms)
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{
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send_bitmap_header(f, dbms, DIRTY_BITMAP_MIG_FLAG_COMPLETE);
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}
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static void send_bitmap_bits(QEMUFile *f, DirtyBitmapMigBitmapState *dbms,
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uint64_t start_sector, uint32_t nr_sectors)
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{
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/* align for buffer_is_zero() */
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uint64_t align = 4 * sizeof(long);
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uint64_t unaligned_size =
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bdrv_dirty_bitmap_serialization_size(
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dbms->bitmap, start_sector << BDRV_SECTOR_BITS,
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(uint64_t)nr_sectors << BDRV_SECTOR_BITS);
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uint64_t buf_size = QEMU_ALIGN_UP(unaligned_size, align);
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uint8_t *buf = g_malloc0(buf_size);
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uint32_t flags = DIRTY_BITMAP_MIG_FLAG_BITS;
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bdrv_dirty_bitmap_serialize_part(
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dbms->bitmap, buf, start_sector << BDRV_SECTOR_BITS,
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(uint64_t)nr_sectors << BDRV_SECTOR_BITS);
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if (buffer_is_zero(buf, buf_size)) {
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g_free(buf);
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buf = NULL;
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flags |= DIRTY_BITMAP_MIG_FLAG_ZEROES;
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}
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trace_send_bitmap_bits(flags, start_sector, nr_sectors, buf_size);
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send_bitmap_header(f, dbms, flags);
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qemu_put_be64(f, start_sector);
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qemu_put_be32(f, nr_sectors);
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/* if a block is zero we need to flush here since the network
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* bandwidth is now a lot higher than the storage device bandwidth.
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* thus if we queue zero blocks we slow down the migration. */
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if (flags & DIRTY_BITMAP_MIG_FLAG_ZEROES) {
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qemu_fflush(f);
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} else {
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qemu_put_be64(f, buf_size);
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qemu_put_buffer(f, buf, buf_size);
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}
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g_free(buf);
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}
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/* Called with iothread lock taken. */
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static void dirty_bitmap_mig_cleanup(void)
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{
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DirtyBitmapMigBitmapState *dbms;
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while ((dbms = QSIMPLEQ_FIRST(&dirty_bitmap_mig_state.dbms_list)) != NULL) {
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QSIMPLEQ_REMOVE_HEAD(&dirty_bitmap_mig_state.dbms_list, entry);
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bdrv_dirty_bitmap_set_qmp_locked(dbms->bitmap, false);
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bdrv_unref(dbms->bs);
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g_free(dbms);
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}
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}
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/* Called with iothread lock taken. */
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static int init_dirty_bitmap_migration(void)
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{
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BlockDriverState *bs;
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BdrvDirtyBitmap *bitmap;
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DirtyBitmapMigBitmapState *dbms;
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BdrvNextIterator it;
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dirty_bitmap_mig_state.bulk_completed = false;
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dirty_bitmap_mig_state.prev_bs = NULL;
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dirty_bitmap_mig_state.prev_bitmap = NULL;
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dirty_bitmap_mig_state.no_bitmaps = false;
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for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
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const char *drive_name = bdrv_get_device_or_node_name(bs);
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/* skip automatically inserted nodes */
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while (bs && bs->drv && bs->implicit) {
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bs = backing_bs(bs);
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}
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for (bitmap = bdrv_dirty_bitmap_next(bs, NULL); bitmap;
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bitmap = bdrv_dirty_bitmap_next(bs, bitmap))
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{
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if (!bdrv_dirty_bitmap_name(bitmap)) {
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continue;
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}
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if (drive_name == NULL) {
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error_report("Found bitmap '%s' in unnamed node %p. It can't "
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"be migrated", bdrv_dirty_bitmap_name(bitmap), bs);
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goto fail;
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}
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if (bdrv_dirty_bitmap_user_locked(bitmap)) {
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error_report("Can't migrate a bitmap that is in use by another operation: '%s'",
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bdrv_dirty_bitmap_name(bitmap));
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goto fail;
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}
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if (bdrv_dirty_bitmap_readonly(bitmap)) {
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error_report("Can't migrate read-only dirty bitmap: '%s",
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bdrv_dirty_bitmap_name(bitmap));
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goto fail;
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}
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bdrv_ref(bs);
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bdrv_dirty_bitmap_set_qmp_locked(bitmap, true);
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dbms = g_new0(DirtyBitmapMigBitmapState, 1);
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dbms->bs = bs;
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dbms->node_name = drive_name;
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dbms->bitmap = bitmap;
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dbms->total_sectors = bdrv_nb_sectors(bs);
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dbms->sectors_per_chunk = CHUNK_SIZE * 8 *
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bdrv_dirty_bitmap_granularity(bitmap) >> BDRV_SECTOR_BITS;
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if (bdrv_dirty_bitmap_enabled(bitmap)) {
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dbms->flags |= DIRTY_BITMAP_MIG_START_FLAG_ENABLED;
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}
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if (bdrv_dirty_bitmap_get_persistance(bitmap)) {
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dbms->flags |= DIRTY_BITMAP_MIG_START_FLAG_PERSISTENT;
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}
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QSIMPLEQ_INSERT_TAIL(&dirty_bitmap_mig_state.dbms_list,
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dbms, entry);
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}
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}
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/* unset migration flags here, to not roll back it */
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QSIMPLEQ_FOREACH(dbms, &dirty_bitmap_mig_state.dbms_list, entry) {
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bdrv_dirty_bitmap_set_migration(dbms->bitmap, true);
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}
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if (QSIMPLEQ_EMPTY(&dirty_bitmap_mig_state.dbms_list)) {
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dirty_bitmap_mig_state.no_bitmaps = true;
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}
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return 0;
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fail:
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dirty_bitmap_mig_cleanup();
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return -1;
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}
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/* Called with no lock taken. */
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static void bulk_phase_send_chunk(QEMUFile *f, DirtyBitmapMigBitmapState *dbms)
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{
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uint32_t nr_sectors = MIN(dbms->total_sectors - dbms->cur_sector,
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dbms->sectors_per_chunk);
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send_bitmap_bits(f, dbms, dbms->cur_sector, nr_sectors);
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dbms->cur_sector += nr_sectors;
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if (dbms->cur_sector >= dbms->total_sectors) {
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dbms->bulk_completed = true;
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}
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}
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/* Called with no lock taken. */
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static void bulk_phase(QEMUFile *f, bool limit)
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{
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DirtyBitmapMigBitmapState *dbms;
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QSIMPLEQ_FOREACH(dbms, &dirty_bitmap_mig_state.dbms_list, entry) {
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while (!dbms->bulk_completed) {
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bulk_phase_send_chunk(f, dbms);
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if (limit && qemu_file_rate_limit(f)) {
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return;
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}
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}
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}
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dirty_bitmap_mig_state.bulk_completed = true;
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}
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/* for SaveVMHandlers */
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static void dirty_bitmap_save_cleanup(void *opaque)
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{
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dirty_bitmap_mig_cleanup();
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}
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static int dirty_bitmap_save_iterate(QEMUFile *f, void *opaque)
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{
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trace_dirty_bitmap_save_iterate(migration_in_postcopy());
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if (migration_in_postcopy() && !dirty_bitmap_mig_state.bulk_completed) {
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bulk_phase(f, true);
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}
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qemu_put_bitmap_flags(f, DIRTY_BITMAP_MIG_FLAG_EOS);
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return dirty_bitmap_mig_state.bulk_completed;
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}
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/* Called with iothread lock taken. */
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static int dirty_bitmap_save_complete(QEMUFile *f, void *opaque)
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{
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DirtyBitmapMigBitmapState *dbms;
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trace_dirty_bitmap_save_complete_enter();
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if (!dirty_bitmap_mig_state.bulk_completed) {
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bulk_phase(f, false);
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}
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QSIMPLEQ_FOREACH(dbms, &dirty_bitmap_mig_state.dbms_list, entry) {
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send_bitmap_complete(f, dbms);
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}
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qemu_put_bitmap_flags(f, DIRTY_BITMAP_MIG_FLAG_EOS);
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trace_dirty_bitmap_save_complete_finish();
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dirty_bitmap_mig_cleanup();
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return 0;
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}
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static void dirty_bitmap_save_pending(QEMUFile *f, void *opaque,
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uint64_t max_size,
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uint64_t *res_precopy_only,
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uint64_t *res_compatible,
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uint64_t *res_postcopy_only)
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{
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DirtyBitmapMigBitmapState *dbms;
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uint64_t pending = 0;
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qemu_mutex_lock_iothread();
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QSIMPLEQ_FOREACH(dbms, &dirty_bitmap_mig_state.dbms_list, entry) {
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uint64_t gran = bdrv_dirty_bitmap_granularity(dbms->bitmap);
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uint64_t sectors = dbms->bulk_completed ? 0 :
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dbms->total_sectors - dbms->cur_sector;
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pending += DIV_ROUND_UP(sectors * BDRV_SECTOR_SIZE, gran);
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}
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qemu_mutex_unlock_iothread();
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trace_dirty_bitmap_save_pending(pending, max_size);
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*res_postcopy_only += pending;
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}
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/* First occurrence of this bitmap. It should be created if doesn't exist */
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static int dirty_bitmap_load_start(QEMUFile *f, DirtyBitmapLoadState *s)
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{
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Error *local_err = NULL;
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uint32_t granularity = qemu_get_be32(f);
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uint8_t flags = qemu_get_byte(f);
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if (s->bitmap) {
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error_report("Bitmap with the same name ('%s') already exists on "
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"destination", bdrv_dirty_bitmap_name(s->bitmap));
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return -EINVAL;
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} else {
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s->bitmap = bdrv_create_dirty_bitmap(s->bs, granularity,
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s->bitmap_name, &local_err);
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if (!s->bitmap) {
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error_report_err(local_err);
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return -EINVAL;
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}
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}
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if (flags & DIRTY_BITMAP_MIG_START_FLAG_RESERVED_MASK) {
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error_report("Unknown flags in migrated dirty bitmap header: %x",
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flags);
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return -EINVAL;
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}
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if (flags & DIRTY_BITMAP_MIG_START_FLAG_PERSISTENT) {
|
|
bdrv_dirty_bitmap_set_persistance(s->bitmap, true);
|
|
}
|
|
|
|
bdrv_disable_dirty_bitmap(s->bitmap);
|
|
if (flags & DIRTY_BITMAP_MIG_START_FLAG_ENABLED) {
|
|
DirtyBitmapLoadBitmapState *b;
|
|
|
|
bdrv_dirty_bitmap_create_successor(s->bs, s->bitmap, &local_err);
|
|
if (local_err) {
|
|
error_report_err(local_err);
|
|
return -EINVAL;
|
|
}
|
|
|
|
b = g_new(DirtyBitmapLoadBitmapState, 1);
|
|
b->bs = s->bs;
|
|
b->bitmap = s->bitmap;
|
|
b->migrated = false;
|
|
enabled_bitmaps = g_slist_prepend(enabled_bitmaps, b);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void dirty_bitmap_mig_before_vm_start(void)
|
|
{
|
|
GSList *item;
|
|
|
|
qemu_mutex_lock(&finish_lock);
|
|
|
|
for (item = enabled_bitmaps; item; item = g_slist_next(item)) {
|
|
DirtyBitmapLoadBitmapState *b = item->data;
|
|
|
|
if (b->migrated) {
|
|
bdrv_enable_dirty_bitmap_locked(b->bitmap);
|
|
} else {
|
|
bdrv_dirty_bitmap_enable_successor(b->bitmap);
|
|
}
|
|
|
|
g_free(b);
|
|
}
|
|
|
|
g_slist_free(enabled_bitmaps);
|
|
enabled_bitmaps = NULL;
|
|
|
|
qemu_mutex_unlock(&finish_lock);
|
|
}
|
|
|
|
static void dirty_bitmap_load_complete(QEMUFile *f, DirtyBitmapLoadState *s)
|
|
{
|
|
GSList *item;
|
|
trace_dirty_bitmap_load_complete();
|
|
bdrv_dirty_bitmap_deserialize_finish(s->bitmap);
|
|
|
|
qemu_mutex_lock(&finish_lock);
|
|
|
|
for (item = enabled_bitmaps; item; item = g_slist_next(item)) {
|
|
DirtyBitmapLoadBitmapState *b = item->data;
|
|
|
|
if (b->bitmap == s->bitmap) {
|
|
b->migrated = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (bdrv_dirty_bitmap_frozen(s->bitmap)) {
|
|
bdrv_dirty_bitmap_lock(s->bitmap);
|
|
if (enabled_bitmaps == NULL) {
|
|
/* in postcopy */
|
|
bdrv_reclaim_dirty_bitmap_locked(s->bs, s->bitmap, &error_abort);
|
|
bdrv_enable_dirty_bitmap_locked(s->bitmap);
|
|
} else {
|
|
/* target not started, successor must be empty */
|
|
int64_t count = bdrv_get_dirty_count(s->bitmap);
|
|
BdrvDirtyBitmap *ret = bdrv_reclaim_dirty_bitmap_locked(s->bs,
|
|
s->bitmap,
|
|
NULL);
|
|
/* bdrv_reclaim_dirty_bitmap can fail only on no successor (it
|
|
* must be) or on merge fail, but merge can't fail when second
|
|
* bitmap is empty
|
|
*/
|
|
assert(ret == s->bitmap &&
|
|
count == bdrv_get_dirty_count(s->bitmap));
|
|
}
|
|
bdrv_dirty_bitmap_unlock(s->bitmap);
|
|
}
|
|
|
|
qemu_mutex_unlock(&finish_lock);
|
|
}
|
|
|
|
static int dirty_bitmap_load_bits(QEMUFile *f, DirtyBitmapLoadState *s)
|
|
{
|
|
uint64_t first_byte = qemu_get_be64(f) << BDRV_SECTOR_BITS;
|
|
uint64_t nr_bytes = (uint64_t)qemu_get_be32(f) << BDRV_SECTOR_BITS;
|
|
trace_dirty_bitmap_load_bits_enter(first_byte >> BDRV_SECTOR_BITS,
|
|
nr_bytes >> BDRV_SECTOR_BITS);
|
|
|
|
if (s->flags & DIRTY_BITMAP_MIG_FLAG_ZEROES) {
|
|
trace_dirty_bitmap_load_bits_zeroes();
|
|
bdrv_dirty_bitmap_deserialize_zeroes(s->bitmap, first_byte, nr_bytes,
|
|
false);
|
|
} else {
|
|
size_t ret;
|
|
uint8_t *buf;
|
|
uint64_t buf_size = qemu_get_be64(f);
|
|
uint64_t needed_size =
|
|
bdrv_dirty_bitmap_serialization_size(s->bitmap,
|
|
first_byte, nr_bytes);
|
|
|
|
if (needed_size > buf_size ||
|
|
buf_size > QEMU_ALIGN_UP(needed_size, 4 * sizeof(long))
|
|
/* Here used same alignment as in send_bitmap_bits */
|
|
) {
|
|
error_report("Migrated bitmap granularity doesn't "
|
|
"match the destination bitmap '%s' granularity",
|
|
bdrv_dirty_bitmap_name(s->bitmap));
|
|
return -EINVAL;
|
|
}
|
|
|
|
buf = g_malloc(buf_size);
|
|
ret = qemu_get_buffer(f, buf, buf_size);
|
|
if (ret != buf_size) {
|
|
error_report("Failed to read bitmap bits");
|
|
g_free(buf);
|
|
return -EIO;
|
|
}
|
|
|
|
bdrv_dirty_bitmap_deserialize_part(s->bitmap, buf, first_byte, nr_bytes,
|
|
false);
|
|
g_free(buf);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dirty_bitmap_load_header(QEMUFile *f, DirtyBitmapLoadState *s)
|
|
{
|
|
Error *local_err = NULL;
|
|
bool nothing;
|
|
s->flags = qemu_get_bitmap_flags(f);
|
|
trace_dirty_bitmap_load_header(s->flags);
|
|
|
|
nothing = s->flags == (s->flags & DIRTY_BITMAP_MIG_FLAG_EOS);
|
|
|
|
if (s->flags & DIRTY_BITMAP_MIG_FLAG_DEVICE_NAME) {
|
|
if (!qemu_get_counted_string(f, s->node_name)) {
|
|
error_report("Unable to read node name string");
|
|
return -EINVAL;
|
|
}
|
|
s->bs = bdrv_lookup_bs(s->node_name, s->node_name, &local_err);
|
|
if (!s->bs) {
|
|
error_report_err(local_err);
|
|
return -EINVAL;
|
|
}
|
|
} else if (!s->bs && !nothing) {
|
|
error_report("Error: block device name is not set");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (s->flags & DIRTY_BITMAP_MIG_FLAG_BITMAP_NAME) {
|
|
if (!qemu_get_counted_string(f, s->bitmap_name)) {
|
|
error_report("Unable to read bitmap name string");
|
|
return -EINVAL;
|
|
}
|
|
s->bitmap = bdrv_find_dirty_bitmap(s->bs, s->bitmap_name);
|
|
|
|
/* bitmap may be NULL here, it wouldn't be an error if it is the
|
|
* first occurrence of the bitmap */
|
|
if (!s->bitmap && !(s->flags & DIRTY_BITMAP_MIG_FLAG_START)) {
|
|
error_report("Error: unknown dirty bitmap "
|
|
"'%s' for block device '%s'",
|
|
s->bitmap_name, s->node_name);
|
|
return -EINVAL;
|
|
}
|
|
} else if (!s->bitmap && !nothing) {
|
|
error_report("Error: block device name is not set");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dirty_bitmap_load(QEMUFile *f, void *opaque, int version_id)
|
|
{
|
|
static DirtyBitmapLoadState s;
|
|
int ret = 0;
|
|
|
|
trace_dirty_bitmap_load_enter();
|
|
|
|
if (version_id != 1) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
do {
|
|
ret = dirty_bitmap_load_header(f, &s);
|
|
if (ret < 0) {
|
|
return ret;
|
|
}
|
|
|
|
if (s.flags & DIRTY_BITMAP_MIG_FLAG_START) {
|
|
ret = dirty_bitmap_load_start(f, &s);
|
|
} else if (s.flags & DIRTY_BITMAP_MIG_FLAG_COMPLETE) {
|
|
dirty_bitmap_load_complete(f, &s);
|
|
} else if (s.flags & DIRTY_BITMAP_MIG_FLAG_BITS) {
|
|
ret = dirty_bitmap_load_bits(f, &s);
|
|
}
|
|
|
|
if (!ret) {
|
|
ret = qemu_file_get_error(f);
|
|
}
|
|
|
|
if (ret) {
|
|
return ret;
|
|
}
|
|
} while (!(s.flags & DIRTY_BITMAP_MIG_FLAG_EOS));
|
|
|
|
trace_dirty_bitmap_load_success();
|
|
return 0;
|
|
}
|
|
|
|
static int dirty_bitmap_save_setup(QEMUFile *f, void *opaque)
|
|
{
|
|
DirtyBitmapMigBitmapState *dbms = NULL;
|
|
if (init_dirty_bitmap_migration() < 0) {
|
|
return -1;
|
|
}
|
|
|
|
QSIMPLEQ_FOREACH(dbms, &dirty_bitmap_mig_state.dbms_list, entry) {
|
|
send_bitmap_start(f, dbms);
|
|
}
|
|
qemu_put_bitmap_flags(f, DIRTY_BITMAP_MIG_FLAG_EOS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool dirty_bitmap_is_active(void *opaque)
|
|
{
|
|
return migrate_dirty_bitmaps() && !dirty_bitmap_mig_state.no_bitmaps;
|
|
}
|
|
|
|
static bool dirty_bitmap_is_active_iterate(void *opaque)
|
|
{
|
|
return dirty_bitmap_is_active(opaque) && !runstate_is_running();
|
|
}
|
|
|
|
static bool dirty_bitmap_has_postcopy(void *opaque)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
static SaveVMHandlers savevm_dirty_bitmap_handlers = {
|
|
.save_setup = dirty_bitmap_save_setup,
|
|
.save_live_complete_postcopy = dirty_bitmap_save_complete,
|
|
.save_live_complete_precopy = dirty_bitmap_save_complete,
|
|
.has_postcopy = dirty_bitmap_has_postcopy,
|
|
.save_live_pending = dirty_bitmap_save_pending,
|
|
.save_live_iterate = dirty_bitmap_save_iterate,
|
|
.is_active_iterate = dirty_bitmap_is_active_iterate,
|
|
.load_state = dirty_bitmap_load,
|
|
.save_cleanup = dirty_bitmap_save_cleanup,
|
|
.is_active = dirty_bitmap_is_active,
|
|
};
|
|
|
|
void dirty_bitmap_mig_init(void)
|
|
{
|
|
QSIMPLEQ_INIT(&dirty_bitmap_mig_state.dbms_list);
|
|
|
|
register_savevm_live(NULL, "dirty-bitmap", 0, 1,
|
|
&savevm_dirty_bitmap_handlers,
|
|
&dirty_bitmap_mig_state);
|
|
}
|