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67a0fd2a9b
The added parameter can be used to return the BDS pointer which the valid offset is referring to. Its value should be ignored unless BDRV_BLOCK_OFFSET_VALID in ret is set. Until block drivers fill in the right value, let's clear it explicitly right before calling .bdrv_get_block_status. The "bs->file" condition in bdrv_co_get_block_status is kept now to keep iotest case 102 passing, and will be fixed once all drivers return the right file pointer. Signed-off-by: Fam Zheng <famz@redhat.com> Message-id: 1453780743-16806-2-git-send-email-famz@redhat.com Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
880 lines
28 KiB
C
880 lines
28 KiB
C
/*
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* Image mirroring
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*
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* Copyright Red Hat, Inc. 2012
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*
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* Authors:
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* Paolo Bonzini <pbonzini@redhat.com>
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*
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* This work is licensed under the terms of the GNU LGPL, version 2 or later.
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* See the COPYING.LIB file in the top-level directory.
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*
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*/
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#include "qemu/osdep.h"
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#include "trace.h"
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#include "block/blockjob.h"
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#include "block/block_int.h"
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#include "sysemu/block-backend.h"
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#include "qapi/qmp/qerror.h"
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#include "qemu/ratelimit.h"
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#include "qemu/bitmap.h"
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#include "qemu/error-report.h"
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#define SLICE_TIME 100000000ULL /* ns */
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#define MAX_IN_FLIGHT 16
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#define DEFAULT_MIRROR_BUF_SIZE (10 << 20)
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/* The mirroring buffer is a list of granularity-sized chunks.
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* Free chunks are organized in a list.
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*/
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typedef struct MirrorBuffer {
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QSIMPLEQ_ENTRY(MirrorBuffer) next;
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} MirrorBuffer;
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typedef struct MirrorBlockJob {
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BlockJob common;
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RateLimit limit;
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BlockDriverState *target;
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BlockDriverState *base;
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/* The name of the graph node to replace */
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char *replaces;
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/* The BDS to replace */
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BlockDriverState *to_replace;
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/* Used to block operations on the drive-mirror-replace target */
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Error *replace_blocker;
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bool is_none_mode;
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BlockdevOnError on_source_error, on_target_error;
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bool synced;
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bool should_complete;
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int64_t sector_num;
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int64_t granularity;
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size_t buf_size;
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int64_t bdev_length;
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unsigned long *cow_bitmap;
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BdrvDirtyBitmap *dirty_bitmap;
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HBitmapIter hbi;
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uint8_t *buf;
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QSIMPLEQ_HEAD(, MirrorBuffer) buf_free;
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int buf_free_count;
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unsigned long *in_flight_bitmap;
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int in_flight;
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int sectors_in_flight;
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int ret;
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bool unmap;
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bool waiting_for_io;
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} MirrorBlockJob;
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typedef struct MirrorOp {
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MirrorBlockJob *s;
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QEMUIOVector qiov;
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int64_t sector_num;
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int nb_sectors;
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} MirrorOp;
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static BlockErrorAction mirror_error_action(MirrorBlockJob *s, bool read,
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int error)
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{
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s->synced = false;
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if (read) {
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return block_job_error_action(&s->common, s->common.bs,
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s->on_source_error, true, error);
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} else {
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return block_job_error_action(&s->common, s->target,
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s->on_target_error, false, error);
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}
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}
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static void mirror_iteration_done(MirrorOp *op, int ret)
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{
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MirrorBlockJob *s = op->s;
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struct iovec *iov;
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int64_t chunk_num;
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int i, nb_chunks, sectors_per_chunk;
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trace_mirror_iteration_done(s, op->sector_num, op->nb_sectors, ret);
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s->in_flight--;
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s->sectors_in_flight -= op->nb_sectors;
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iov = op->qiov.iov;
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for (i = 0; i < op->qiov.niov; i++) {
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MirrorBuffer *buf = (MirrorBuffer *) iov[i].iov_base;
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QSIMPLEQ_INSERT_TAIL(&s->buf_free, buf, next);
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s->buf_free_count++;
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}
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sectors_per_chunk = s->granularity >> BDRV_SECTOR_BITS;
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chunk_num = op->sector_num / sectors_per_chunk;
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nb_chunks = op->nb_sectors / sectors_per_chunk;
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bitmap_clear(s->in_flight_bitmap, chunk_num, nb_chunks);
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if (ret >= 0) {
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if (s->cow_bitmap) {
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bitmap_set(s->cow_bitmap, chunk_num, nb_chunks);
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}
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s->common.offset += (uint64_t)op->nb_sectors * BDRV_SECTOR_SIZE;
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}
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qemu_iovec_destroy(&op->qiov);
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g_free(op);
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if (s->waiting_for_io) {
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qemu_coroutine_enter(s->common.co, NULL);
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}
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}
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static void mirror_write_complete(void *opaque, int ret)
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{
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MirrorOp *op = opaque;
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MirrorBlockJob *s = op->s;
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if (ret < 0) {
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BlockErrorAction action;
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bdrv_set_dirty_bitmap(s->dirty_bitmap, op->sector_num, op->nb_sectors);
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action = mirror_error_action(s, false, -ret);
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if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
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s->ret = ret;
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}
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}
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mirror_iteration_done(op, ret);
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}
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static void mirror_read_complete(void *opaque, int ret)
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{
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MirrorOp *op = opaque;
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MirrorBlockJob *s = op->s;
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if (ret < 0) {
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BlockErrorAction action;
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bdrv_set_dirty_bitmap(s->dirty_bitmap, op->sector_num, op->nb_sectors);
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action = mirror_error_action(s, true, -ret);
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if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
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s->ret = ret;
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}
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mirror_iteration_done(op, ret);
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return;
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}
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bdrv_aio_writev(s->target, op->sector_num, &op->qiov, op->nb_sectors,
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mirror_write_complete, op);
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}
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static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
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{
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BlockDriverState *source = s->common.bs;
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int nb_sectors, sectors_per_chunk, nb_chunks, max_iov;
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int64_t end, sector_num, next_chunk, next_sector, hbitmap_next_sector;
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uint64_t delay_ns = 0;
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MirrorOp *op;
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int pnum;
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int64_t ret;
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BlockDriverState *file;
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max_iov = MIN(source->bl.max_iov, s->target->bl.max_iov);
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s->sector_num = hbitmap_iter_next(&s->hbi);
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if (s->sector_num < 0) {
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bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi);
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s->sector_num = hbitmap_iter_next(&s->hbi);
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trace_mirror_restart_iter(s, bdrv_get_dirty_count(s->dirty_bitmap));
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assert(s->sector_num >= 0);
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}
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hbitmap_next_sector = s->sector_num;
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sector_num = s->sector_num;
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sectors_per_chunk = s->granularity >> BDRV_SECTOR_BITS;
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end = s->bdev_length / BDRV_SECTOR_SIZE;
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/* Extend the QEMUIOVector to include all adjacent blocks that will
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* be copied in this operation.
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*
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* We have to do this if we have no backing file yet in the destination,
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* and the cluster size is very large. Then we need to do COW ourselves.
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* The first time a cluster is copied, copy it entirely. Note that,
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* because both the granularity and the cluster size are powers of two,
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* the number of sectors to copy cannot exceed one cluster.
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*
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* We also want to extend the QEMUIOVector to include more adjacent
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* dirty blocks if possible, to limit the number of I/O operations and
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* run efficiently even with a small granularity.
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*/
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nb_chunks = 0;
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nb_sectors = 0;
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next_sector = sector_num;
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next_chunk = sector_num / sectors_per_chunk;
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/* Wait for I/O to this cluster (from a previous iteration) to be done. */
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while (test_bit(next_chunk, s->in_flight_bitmap)) {
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trace_mirror_yield_in_flight(s, sector_num, s->in_flight);
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s->waiting_for_io = true;
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qemu_coroutine_yield();
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s->waiting_for_io = false;
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}
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do {
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int added_sectors, added_chunks;
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if (!bdrv_get_dirty(source, s->dirty_bitmap, next_sector) ||
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test_bit(next_chunk, s->in_flight_bitmap)) {
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assert(nb_sectors > 0);
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break;
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}
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added_sectors = sectors_per_chunk;
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if (s->cow_bitmap && !test_bit(next_chunk, s->cow_bitmap)) {
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bdrv_round_to_clusters(s->target,
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next_sector, added_sectors,
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&next_sector, &added_sectors);
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/* On the first iteration, the rounding may make us copy
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* sectors before the first dirty one.
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*/
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if (next_sector < sector_num) {
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assert(nb_sectors == 0);
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sector_num = next_sector;
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next_chunk = next_sector / sectors_per_chunk;
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}
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}
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added_sectors = MIN(added_sectors, end - (sector_num + nb_sectors));
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added_chunks = (added_sectors + sectors_per_chunk - 1) / sectors_per_chunk;
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/* When doing COW, it may happen that there is not enough space for
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* a full cluster. Wait if that is the case.
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*/
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while (nb_chunks == 0 && s->buf_free_count < added_chunks) {
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trace_mirror_yield_buf_busy(s, nb_chunks, s->in_flight);
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s->waiting_for_io = true;
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qemu_coroutine_yield();
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s->waiting_for_io = false;
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}
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if (s->buf_free_count < nb_chunks + added_chunks) {
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trace_mirror_break_buf_busy(s, nb_chunks, s->in_flight);
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break;
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}
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if (max_iov < nb_chunks + added_chunks) {
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trace_mirror_break_iov_max(s, nb_chunks, added_chunks);
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break;
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}
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/* We have enough free space to copy these sectors. */
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bitmap_set(s->in_flight_bitmap, next_chunk, added_chunks);
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nb_sectors += added_sectors;
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nb_chunks += added_chunks;
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next_sector += added_sectors;
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next_chunk += added_chunks;
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if (!s->synced && s->common.speed) {
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delay_ns = ratelimit_calculate_delay(&s->limit, added_sectors);
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}
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} while (delay_ns == 0 && next_sector < end);
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/* Allocate a MirrorOp that is used as an AIO callback. */
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op = g_new(MirrorOp, 1);
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op->s = s;
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op->sector_num = sector_num;
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op->nb_sectors = nb_sectors;
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/* Now make a QEMUIOVector taking enough granularity-sized chunks
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* from s->buf_free.
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*/
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qemu_iovec_init(&op->qiov, nb_chunks);
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next_sector = sector_num;
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while (nb_chunks-- > 0) {
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MirrorBuffer *buf = QSIMPLEQ_FIRST(&s->buf_free);
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size_t remaining = (nb_sectors * BDRV_SECTOR_SIZE) - op->qiov.size;
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QSIMPLEQ_REMOVE_HEAD(&s->buf_free, next);
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s->buf_free_count--;
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qemu_iovec_add(&op->qiov, buf, MIN(s->granularity, remaining));
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/* Advance the HBitmapIter in parallel, so that we do not examine
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* the same sector twice.
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*/
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if (next_sector > hbitmap_next_sector
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&& bdrv_get_dirty(source, s->dirty_bitmap, next_sector)) {
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hbitmap_next_sector = hbitmap_iter_next(&s->hbi);
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}
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next_sector += sectors_per_chunk;
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}
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bdrv_reset_dirty_bitmap(s->dirty_bitmap, sector_num, nb_sectors);
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/* Copy the dirty cluster. */
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s->in_flight++;
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s->sectors_in_flight += nb_sectors;
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trace_mirror_one_iteration(s, sector_num, nb_sectors);
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ret = bdrv_get_block_status_above(source, NULL, sector_num,
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nb_sectors, &pnum, &file);
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if (ret < 0 || pnum < nb_sectors ||
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(ret & BDRV_BLOCK_DATA && !(ret & BDRV_BLOCK_ZERO))) {
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bdrv_aio_readv(source, sector_num, &op->qiov, nb_sectors,
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mirror_read_complete, op);
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} else if (ret & BDRV_BLOCK_ZERO) {
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bdrv_aio_write_zeroes(s->target, sector_num, op->nb_sectors,
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s->unmap ? BDRV_REQ_MAY_UNMAP : 0,
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mirror_write_complete, op);
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} else {
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assert(!(ret & BDRV_BLOCK_DATA));
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bdrv_aio_discard(s->target, sector_num, op->nb_sectors,
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mirror_write_complete, op);
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}
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return delay_ns;
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}
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static void mirror_free_init(MirrorBlockJob *s)
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{
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int granularity = s->granularity;
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size_t buf_size = s->buf_size;
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uint8_t *buf = s->buf;
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assert(s->buf_free_count == 0);
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QSIMPLEQ_INIT(&s->buf_free);
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while (buf_size != 0) {
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MirrorBuffer *cur = (MirrorBuffer *)buf;
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QSIMPLEQ_INSERT_TAIL(&s->buf_free, cur, next);
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s->buf_free_count++;
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buf_size -= granularity;
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buf += granularity;
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}
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}
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static void mirror_drain(MirrorBlockJob *s)
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{
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while (s->in_flight > 0) {
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s->waiting_for_io = true;
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qemu_coroutine_yield();
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s->waiting_for_io = false;
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}
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}
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typedef struct {
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int ret;
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} MirrorExitData;
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static void mirror_exit(BlockJob *job, void *opaque)
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{
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MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
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MirrorExitData *data = opaque;
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AioContext *replace_aio_context = NULL;
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BlockDriverState *src = s->common.bs;
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/* Make sure that the source BDS doesn't go away before we called
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* block_job_completed(). */
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bdrv_ref(src);
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if (s->to_replace) {
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replace_aio_context = bdrv_get_aio_context(s->to_replace);
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aio_context_acquire(replace_aio_context);
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}
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if (s->should_complete && data->ret == 0) {
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BlockDriverState *to_replace = s->common.bs;
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if (s->to_replace) {
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to_replace = s->to_replace;
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}
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/* This was checked in mirror_start_job(), but meanwhile one of the
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* nodes could have been newly attached to a BlockBackend. */
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if (to_replace->blk && s->target->blk) {
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error_report("block job: Can't create node with two BlockBackends");
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data->ret = -EINVAL;
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goto out;
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}
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if (bdrv_get_flags(s->target) != bdrv_get_flags(to_replace)) {
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bdrv_reopen(s->target, bdrv_get_flags(to_replace), NULL);
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}
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bdrv_replace_in_backing_chain(to_replace, s->target);
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}
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out:
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if (s->to_replace) {
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bdrv_op_unblock_all(s->to_replace, s->replace_blocker);
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error_free(s->replace_blocker);
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bdrv_unref(s->to_replace);
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}
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if (replace_aio_context) {
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aio_context_release(replace_aio_context);
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}
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g_free(s->replaces);
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bdrv_op_unblock_all(s->target, s->common.blocker);
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bdrv_unref(s->target);
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block_job_completed(&s->common, data->ret);
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g_free(data);
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bdrv_drained_end(src);
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bdrv_unref(src);
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}
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static void coroutine_fn mirror_run(void *opaque)
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{
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MirrorBlockJob *s = opaque;
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MirrorExitData *data;
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BlockDriverState *bs = s->common.bs;
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int64_t sector_num, end, length;
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uint64_t last_pause_ns;
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BlockDriverInfo bdi;
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char backing_filename[2]; /* we only need 2 characters because we are only
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checking for a NULL string */
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int ret = 0;
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int n;
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if (block_job_is_cancelled(&s->common)) {
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goto immediate_exit;
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}
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s->bdev_length = bdrv_getlength(bs);
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if (s->bdev_length < 0) {
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ret = s->bdev_length;
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goto immediate_exit;
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} else if (s->bdev_length == 0) {
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/* Report BLOCK_JOB_READY and wait for complete. */
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block_job_event_ready(&s->common);
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s->synced = true;
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while (!block_job_is_cancelled(&s->common) && !s->should_complete) {
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block_job_yield(&s->common);
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}
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s->common.cancelled = false;
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goto immediate_exit;
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}
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length = DIV_ROUND_UP(s->bdev_length, s->granularity);
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s->in_flight_bitmap = bitmap_new(length);
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/* If we have no backing file yet in the destination, we cannot let
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* the destination do COW. Instead, we copy sectors around the
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* dirty data if needed. We need a bitmap to do that.
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*/
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bdrv_get_backing_filename(s->target, backing_filename,
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sizeof(backing_filename));
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if (backing_filename[0] && !s->target->backing) {
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ret = bdrv_get_info(s->target, &bdi);
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if (ret < 0) {
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goto immediate_exit;
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}
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if (s->granularity < bdi.cluster_size) {
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s->buf_size = MAX(s->buf_size, bdi.cluster_size);
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s->cow_bitmap = bitmap_new(length);
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}
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}
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end = s->bdev_length / BDRV_SECTOR_SIZE;
|
|
s->buf = qemu_try_blockalign(bs, s->buf_size);
|
|
if (s->buf == NULL) {
|
|
ret = -ENOMEM;
|
|
goto immediate_exit;
|
|
}
|
|
|
|
mirror_free_init(s);
|
|
|
|
last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
|
|
if (!s->is_none_mode) {
|
|
/* First part, loop on the sectors and initialize the dirty bitmap. */
|
|
BlockDriverState *base = s->base;
|
|
bool mark_all_dirty = s->base == NULL && !bdrv_has_zero_init(s->target);
|
|
|
|
for (sector_num = 0; sector_num < end; ) {
|
|
/* Just to make sure we are not exceeding int limit. */
|
|
int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS,
|
|
end - sector_num);
|
|
int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
|
|
|
|
if (now - last_pause_ns > SLICE_TIME) {
|
|
last_pause_ns = now;
|
|
block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0);
|
|
}
|
|
|
|
if (block_job_is_cancelled(&s->common)) {
|
|
goto immediate_exit;
|
|
}
|
|
|
|
ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n);
|
|
|
|
if (ret < 0) {
|
|
goto immediate_exit;
|
|
}
|
|
|
|
assert(n > 0);
|
|
if (ret == 1 || mark_all_dirty) {
|
|
bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n);
|
|
}
|
|
sector_num += n;
|
|
}
|
|
}
|
|
|
|
bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi);
|
|
for (;;) {
|
|
uint64_t delay_ns = 0;
|
|
int64_t cnt;
|
|
bool should_complete;
|
|
|
|
if (s->ret < 0) {
|
|
ret = s->ret;
|
|
goto immediate_exit;
|
|
}
|
|
|
|
cnt = bdrv_get_dirty_count(s->dirty_bitmap);
|
|
/* s->common.offset contains the number of bytes already processed so
|
|
* far, cnt is the number of dirty sectors remaining and
|
|
* s->sectors_in_flight is the number of sectors currently being
|
|
* processed; together those are the current total operation length */
|
|
s->common.len = s->common.offset +
|
|
(cnt + s->sectors_in_flight) * BDRV_SECTOR_SIZE;
|
|
|
|
/* Note that even when no rate limit is applied we need to yield
|
|
* periodically with no pending I/O so that bdrv_drain_all() returns.
|
|
* We do so every SLICE_TIME nanoseconds, or when there is an error,
|
|
* or when the source is clean, whichever comes first.
|
|
*/
|
|
if (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - last_pause_ns < SLICE_TIME &&
|
|
s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
|
|
if (s->in_flight == MAX_IN_FLIGHT || s->buf_free_count == 0 ||
|
|
(cnt == 0 && s->in_flight > 0)) {
|
|
trace_mirror_yield(s, s->in_flight, s->buf_free_count, cnt);
|
|
s->waiting_for_io = true;
|
|
qemu_coroutine_yield();
|
|
s->waiting_for_io = false;
|
|
continue;
|
|
} else if (cnt != 0) {
|
|
delay_ns = mirror_iteration(s);
|
|
}
|
|
}
|
|
|
|
should_complete = false;
|
|
if (s->in_flight == 0 && cnt == 0) {
|
|
trace_mirror_before_flush(s);
|
|
ret = bdrv_flush(s->target);
|
|
if (ret < 0) {
|
|
if (mirror_error_action(s, false, -ret) ==
|
|
BLOCK_ERROR_ACTION_REPORT) {
|
|
goto immediate_exit;
|
|
}
|
|
} else {
|
|
/* We're out of the streaming phase. From now on, if the job
|
|
* is cancelled we will actually complete all pending I/O and
|
|
* report completion. This way, block-job-cancel will leave
|
|
* the target in a consistent state.
|
|
*/
|
|
if (!s->synced) {
|
|
block_job_event_ready(&s->common);
|
|
s->synced = true;
|
|
}
|
|
|
|
should_complete = s->should_complete ||
|
|
block_job_is_cancelled(&s->common);
|
|
cnt = bdrv_get_dirty_count(s->dirty_bitmap);
|
|
}
|
|
}
|
|
|
|
if (cnt == 0 && should_complete) {
|
|
/* The dirty bitmap is not updated while operations are pending.
|
|
* If we're about to exit, wait for pending operations before
|
|
* calling bdrv_get_dirty_count(bs), or we may exit while the
|
|
* source has dirty data to copy!
|
|
*
|
|
* Note that I/O can be submitted by the guest while
|
|
* mirror_populate runs.
|
|
*/
|
|
trace_mirror_before_drain(s, cnt);
|
|
bdrv_drain(bs);
|
|
cnt = bdrv_get_dirty_count(s->dirty_bitmap);
|
|
}
|
|
|
|
ret = 0;
|
|
trace_mirror_before_sleep(s, cnt, s->synced, delay_ns);
|
|
if (!s->synced) {
|
|
block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
|
|
if (block_job_is_cancelled(&s->common)) {
|
|
break;
|
|
}
|
|
} else if (!should_complete) {
|
|
delay_ns = (s->in_flight == 0 && cnt == 0 ? SLICE_TIME : 0);
|
|
block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
|
|
} else if (cnt == 0) {
|
|
/* The two disks are in sync. Exit and report successful
|
|
* completion.
|
|
*/
|
|
assert(QLIST_EMPTY(&bs->tracked_requests));
|
|
s->common.cancelled = false;
|
|
break;
|
|
}
|
|
last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
|
|
}
|
|
|
|
immediate_exit:
|
|
if (s->in_flight > 0) {
|
|
/* We get here only if something went wrong. Either the job failed,
|
|
* or it was cancelled prematurely so that we do not guarantee that
|
|
* the target is a copy of the source.
|
|
*/
|
|
assert(ret < 0 || (!s->synced && block_job_is_cancelled(&s->common)));
|
|
mirror_drain(s);
|
|
}
|
|
|
|
assert(s->in_flight == 0);
|
|
qemu_vfree(s->buf);
|
|
g_free(s->cow_bitmap);
|
|
g_free(s->in_flight_bitmap);
|
|
bdrv_release_dirty_bitmap(bs, s->dirty_bitmap);
|
|
if (s->target->blk) {
|
|
blk_iostatus_disable(s->target->blk);
|
|
}
|
|
|
|
data = g_malloc(sizeof(*data));
|
|
data->ret = ret;
|
|
/* Before we switch to target in mirror_exit, make sure data doesn't
|
|
* change. */
|
|
bdrv_drained_begin(s->common.bs);
|
|
block_job_defer_to_main_loop(&s->common, mirror_exit, data);
|
|
}
|
|
|
|
static void mirror_set_speed(BlockJob *job, int64_t speed, Error **errp)
|
|
{
|
|
MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
|
|
|
|
if (speed < 0) {
|
|
error_setg(errp, QERR_INVALID_PARAMETER, "speed");
|
|
return;
|
|
}
|
|
ratelimit_set_speed(&s->limit, speed / BDRV_SECTOR_SIZE, SLICE_TIME);
|
|
}
|
|
|
|
static void mirror_iostatus_reset(BlockJob *job)
|
|
{
|
|
MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
|
|
|
|
if (s->target->blk) {
|
|
blk_iostatus_reset(s->target->blk);
|
|
}
|
|
}
|
|
|
|
static void mirror_complete(BlockJob *job, Error **errp)
|
|
{
|
|
MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
|
|
Error *local_err = NULL;
|
|
int ret;
|
|
|
|
ret = bdrv_open_backing_file(s->target, NULL, "backing", &local_err);
|
|
if (ret < 0) {
|
|
error_propagate(errp, local_err);
|
|
return;
|
|
}
|
|
if (!s->synced) {
|
|
error_setg(errp, QERR_BLOCK_JOB_NOT_READY, job->id);
|
|
return;
|
|
}
|
|
|
|
/* check the target bs is not blocked and block all operations on it */
|
|
if (s->replaces) {
|
|
AioContext *replace_aio_context;
|
|
|
|
s->to_replace = bdrv_find_node(s->replaces);
|
|
if (!s->to_replace) {
|
|
error_setg(errp, "Node name '%s' not found", s->replaces);
|
|
return;
|
|
}
|
|
|
|
replace_aio_context = bdrv_get_aio_context(s->to_replace);
|
|
aio_context_acquire(replace_aio_context);
|
|
|
|
error_setg(&s->replace_blocker,
|
|
"block device is in use by block-job-complete");
|
|
bdrv_op_block_all(s->to_replace, s->replace_blocker);
|
|
bdrv_ref(s->to_replace);
|
|
|
|
aio_context_release(replace_aio_context);
|
|
}
|
|
|
|
s->should_complete = true;
|
|
block_job_enter(&s->common);
|
|
}
|
|
|
|
static const BlockJobDriver mirror_job_driver = {
|
|
.instance_size = sizeof(MirrorBlockJob),
|
|
.job_type = BLOCK_JOB_TYPE_MIRROR,
|
|
.set_speed = mirror_set_speed,
|
|
.iostatus_reset= mirror_iostatus_reset,
|
|
.complete = mirror_complete,
|
|
};
|
|
|
|
static const BlockJobDriver commit_active_job_driver = {
|
|
.instance_size = sizeof(MirrorBlockJob),
|
|
.job_type = BLOCK_JOB_TYPE_COMMIT,
|
|
.set_speed = mirror_set_speed,
|
|
.iostatus_reset
|
|
= mirror_iostatus_reset,
|
|
.complete = mirror_complete,
|
|
};
|
|
|
|
static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
|
|
const char *replaces,
|
|
int64_t speed, uint32_t granularity,
|
|
int64_t buf_size,
|
|
BlockdevOnError on_source_error,
|
|
BlockdevOnError on_target_error,
|
|
bool unmap,
|
|
BlockCompletionFunc *cb,
|
|
void *opaque, Error **errp,
|
|
const BlockJobDriver *driver,
|
|
bool is_none_mode, BlockDriverState *base)
|
|
{
|
|
MirrorBlockJob *s;
|
|
BlockDriverState *replaced_bs;
|
|
|
|
if (granularity == 0) {
|
|
granularity = bdrv_get_default_bitmap_granularity(target);
|
|
}
|
|
|
|
assert ((granularity & (granularity - 1)) == 0);
|
|
|
|
if ((on_source_error == BLOCKDEV_ON_ERROR_STOP ||
|
|
on_source_error == BLOCKDEV_ON_ERROR_ENOSPC) &&
|
|
(!bs->blk || !blk_iostatus_is_enabled(bs->blk))) {
|
|
error_setg(errp, QERR_INVALID_PARAMETER, "on-source-error");
|
|
return;
|
|
}
|
|
|
|
if (buf_size < 0) {
|
|
error_setg(errp, "Invalid parameter 'buf-size'");
|
|
return;
|
|
}
|
|
|
|
if (buf_size == 0) {
|
|
buf_size = DEFAULT_MIRROR_BUF_SIZE;
|
|
}
|
|
|
|
/* We can't support this case as long as the block layer can't handle
|
|
* multiple BlockBackends per BlockDriverState. */
|
|
if (replaces) {
|
|
replaced_bs = bdrv_lookup_bs(replaces, replaces, errp);
|
|
if (replaced_bs == NULL) {
|
|
return;
|
|
}
|
|
} else {
|
|
replaced_bs = bs;
|
|
}
|
|
if (replaced_bs->blk && target->blk) {
|
|
error_setg(errp, "Can't create node with two BlockBackends");
|
|
return;
|
|
}
|
|
|
|
s = block_job_create(driver, bs, speed, cb, opaque, errp);
|
|
if (!s) {
|
|
return;
|
|
}
|
|
|
|
s->replaces = g_strdup(replaces);
|
|
s->on_source_error = on_source_error;
|
|
s->on_target_error = on_target_error;
|
|
s->target = target;
|
|
s->is_none_mode = is_none_mode;
|
|
s->base = base;
|
|
s->granularity = granularity;
|
|
s->buf_size = ROUND_UP(buf_size, granularity);
|
|
s->unmap = unmap;
|
|
|
|
s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp);
|
|
if (!s->dirty_bitmap) {
|
|
g_free(s->replaces);
|
|
block_job_unref(&s->common);
|
|
return;
|
|
}
|
|
|
|
bdrv_op_block_all(s->target, s->common.blocker);
|
|
|
|
bdrv_set_enable_write_cache(s->target, true);
|
|
if (s->target->blk) {
|
|
blk_set_on_error(s->target->blk, on_target_error, on_target_error);
|
|
blk_iostatus_enable(s->target->blk);
|
|
}
|
|
s->common.co = qemu_coroutine_create(mirror_run);
|
|
trace_mirror_start(bs, s, s->common.co, opaque);
|
|
qemu_coroutine_enter(s->common.co, s);
|
|
}
|
|
|
|
void mirror_start(BlockDriverState *bs, BlockDriverState *target,
|
|
const char *replaces,
|
|
int64_t speed, uint32_t granularity, int64_t buf_size,
|
|
MirrorSyncMode mode, BlockdevOnError on_source_error,
|
|
BlockdevOnError on_target_error,
|
|
bool unmap,
|
|
BlockCompletionFunc *cb,
|
|
void *opaque, Error **errp)
|
|
{
|
|
bool is_none_mode;
|
|
BlockDriverState *base;
|
|
|
|
if (mode == MIRROR_SYNC_MODE_INCREMENTAL) {
|
|
error_setg(errp, "Sync mode 'incremental' not supported");
|
|
return;
|
|
}
|
|
is_none_mode = mode == MIRROR_SYNC_MODE_NONE;
|
|
base = mode == MIRROR_SYNC_MODE_TOP ? backing_bs(bs) : NULL;
|
|
mirror_start_job(bs, target, replaces,
|
|
speed, granularity, buf_size,
|
|
on_source_error, on_target_error, unmap, cb, opaque, errp,
|
|
&mirror_job_driver, is_none_mode, base);
|
|
}
|
|
|
|
void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
|
|
int64_t speed,
|
|
BlockdevOnError on_error,
|
|
BlockCompletionFunc *cb,
|
|
void *opaque, Error **errp)
|
|
{
|
|
int64_t length, base_length;
|
|
int orig_base_flags;
|
|
int ret;
|
|
Error *local_err = NULL;
|
|
|
|
orig_base_flags = bdrv_get_flags(base);
|
|
|
|
if (bdrv_reopen(base, bs->open_flags, errp)) {
|
|
return;
|
|
}
|
|
|
|
length = bdrv_getlength(bs);
|
|
if (length < 0) {
|
|
error_setg_errno(errp, -length,
|
|
"Unable to determine length of %s", bs->filename);
|
|
goto error_restore_flags;
|
|
}
|
|
|
|
base_length = bdrv_getlength(base);
|
|
if (base_length < 0) {
|
|
error_setg_errno(errp, -base_length,
|
|
"Unable to determine length of %s", base->filename);
|
|
goto error_restore_flags;
|
|
}
|
|
|
|
if (length > base_length) {
|
|
ret = bdrv_truncate(base, length);
|
|
if (ret < 0) {
|
|
error_setg_errno(errp, -ret,
|
|
"Top image %s is larger than base image %s, and "
|
|
"resize of base image failed",
|
|
bs->filename, base->filename);
|
|
goto error_restore_flags;
|
|
}
|
|
}
|
|
|
|
bdrv_ref(base);
|
|
mirror_start_job(bs, base, NULL, speed, 0, 0,
|
|
on_error, on_error, false, cb, opaque, &local_err,
|
|
&commit_active_job_driver, false, base);
|
|
if (local_err) {
|
|
error_propagate(errp, local_err);
|
|
goto error_restore_flags;
|
|
}
|
|
|
|
return;
|
|
|
|
error_restore_flags:
|
|
/* ignore error and errp for bdrv_reopen, because we want to propagate
|
|
* the original error */
|
|
bdrv_reopen(base, orig_base_flags, NULL);
|
|
return;
|
|
}
|