Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 3852 insertions, 0 deletions

diff --git a/blockdev.c b/blockdev.c
new file mode 100644
index 000000000..b35072644
--- /dev/null
+++ b/blockdev.c
@@ -0,0 +1,3852 @@
+/*
+ * QEMU host block devices
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ *
+ * This file incorporates work covered by the following copyright and
+ * permission notice:
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "sysemu/block-backend.h"
+#include "sysemu/blockdev.h"
+#include "hw/block/block.h"
+#include "block/blockjob.h"
+#include "block/qdict.h"
+#include "block/throttle-groups.h"
+#include "monitor/monitor.h"
+#include "qemu/error-report.h"
+#include "qemu/option.h"
+#include "qemu/qemu-print.h"
+#include "qemu/config-file.h"
+#include "qapi/qapi-commands-block.h"
+#include "qapi/qapi-commands-transaction.h"
+#include "qapi/qapi-visit-block-core.h"
+#include "qapi/qmp/qdict.h"
+#include "qapi/qmp/qnum.h"
+#include "qapi/qmp/qstring.h"
+#include "qapi/error.h"
+#include "qapi/qmp/qerror.h"
+#include "qapi/qmp/qlist.h"
+#include "qapi/qobject-output-visitor.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/iothread.h"
+#include "block/block_int.h"
+#include "block/trace.h"
+#include "sysemu/runstate.h"
+#include "sysemu/replay.h"
+#include "qemu/cutils.h"
+#include "qemu/help_option.h"
+#include "qemu/main-loop.h"
+#include "qemu/throttle-options.h"
+
+QTAILQ_HEAD(, BlockDriverState) monitor_bdrv_states =
+    QTAILQ_HEAD_INITIALIZER(monitor_bdrv_states);
+
+void bdrv_set_monitor_owned(BlockDriverState *bs)
+{
+    QTAILQ_INSERT_TAIL(&monitor_bdrv_states, bs, monitor_list);
+}
+
+static const char *const if_name[IF_COUNT] = {
+    [IF_NONE] = "none",
+    [IF_IDE] = "ide",
+    [IF_SCSI] = "scsi",
+    [IF_FLOPPY] = "floppy",
+    [IF_PFLASH] = "pflash",
+    [IF_MTD] = "mtd",
+    [IF_SD] = "sd",
+    [IF_VIRTIO] = "virtio",
+    [IF_XEN] = "xen",
+};
+
+static int if_max_devs[IF_COUNT] = {
+    /*
+     * Do not change these numbers!  They govern how drive option
+     * index maps to unit and bus.  That mapping is ABI.
+     *
+     * All controllers used to implement if=T drives need to support
+     * if_max_devs[T] units, for any T with if_max_devs[T] != 0.
+     * Otherwise, some index values map to "impossible" bus, unit
+     * values.
+     *
+     * For instance, if you change [IF_SCSI] to 255, -drive
+     * if=scsi,index=12 no longer means bus=1,unit=5, but
+     * bus=0,unit=12.  With an lsi53c895a controller (7 units max),
+     * the drive can't be set up.  Regression.
+     */
+    [IF_IDE] = 2,
+    [IF_SCSI] = 7,
+};
+
+/**
+ * Boards may call this to offer board-by-board overrides
+ * of the default, global values.
+ */
+void override_max_devs(BlockInterfaceType type, int max_devs)
+{
+    BlockBackend *blk;
+    DriveInfo *dinfo;
+
+    if (max_devs <= 0) {
+        return;
+    }
+
+    for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
+        dinfo = blk_legacy_dinfo(blk);
+        if (dinfo->type == type) {
+            fprintf(stderr, "Cannot override units-per-bus property of"
+                    " the %s interface, because a drive of that type has"
+                    " already been added.\n", if_name[type]);
+            g_assert_not_reached();
+        }
+    }
+
+    if_max_devs[type] = max_devs;
+}
+
+/*
+ * We automatically delete the drive when a device using it gets
+ * unplugged.  Questionable feature, but we can't just drop it.
+ * Device models call blockdev_mark_auto_del() to schedule the
+ * automatic deletion, and generic qdev code calls blockdev_auto_del()
+ * when deletion is actually safe.
+ */
+void blockdev_mark_auto_del(BlockBackend *blk)
+{
+    DriveInfo *dinfo = blk_legacy_dinfo(blk);
+    BlockJob *job;
+
+    if (!dinfo) {
+        return;
+    }
+
+    for (job = block_job_next(NULL); job; job = block_job_next(job)) {
+        if (block_job_has_bdrv(job, blk_bs(blk))) {
+            AioContext *aio_context = job->job.aio_context;
+            aio_context_acquire(aio_context);
+
+            job_cancel(&job->job, false);
+
+            aio_context_release(aio_context);
+        }
+    }
+
+    dinfo->auto_del = 1;
+}
+
+void blockdev_auto_del(BlockBackend *blk)
+{
+    DriveInfo *dinfo = blk_legacy_dinfo(blk);
+
+    if (dinfo && dinfo->auto_del) {
+        monitor_remove_blk(blk);
+        blk_unref(blk);
+    }
+}
+
+/**
+ * Returns the current mapping of how many units per bus
+ * a particular interface can support.
+ *
+ *  A positive integer indicates n units per bus.
+ *  0 implies the mapping has not been established.
+ * -1 indicates an invalid BlockInterfaceType was given.
+ */
+int drive_get_max_devs(BlockInterfaceType type)
+{
+    if (type >= IF_IDE && type < IF_COUNT) {
+        return if_max_devs[type];
+    }
+
+    return -1;
+}
+
+static int drive_index_to_bus_id(BlockInterfaceType type, int index)
+{
+    int max_devs = if_max_devs[type];
+    return max_devs ? index / max_devs : 0;
+}
+
+static int drive_index_to_unit_id(BlockInterfaceType type, int index)
+{
+    int max_devs = if_max_devs[type];
+    return max_devs ? index % max_devs : index;
+}
+
+QemuOpts *drive_def(const char *optstr)
+{
+    return qemu_opts_parse_noisily(qemu_find_opts("drive"), optstr, false);
+}
+
+QemuOpts *drive_add(BlockInterfaceType type, int index, const char *file,
+                    const char *optstr)
+{
+    QemuOpts *opts;
+
+    opts = drive_def(optstr);
+    if (!opts) {
+        return NULL;
+    }
+    if (type != IF_DEFAULT) {
+        qemu_opt_set(opts, "if", if_name[type], &error_abort);
+    }
+    if (index >= 0) {
+        qemu_opt_set_number(opts, "index", index, &error_abort);
+    }
+    if (file)
+        qemu_opt_set(opts, "file", file, &error_abort);
+    return opts;
+}
+
+DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
+{
+    BlockBackend *blk;
+    DriveInfo *dinfo;
+
+    for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
+        dinfo = blk_legacy_dinfo(blk);
+        if (dinfo && dinfo->type == type
+            && dinfo->bus == bus && dinfo->unit == unit) {
+            return dinfo;
+        }
+    }
+
+    return NULL;
+}
+
+/*
+ * Check board claimed all -drive that are meant to be claimed.
+ * Fatal error if any remain unclaimed.
+ */
+void drive_check_orphaned(void)
+{
+    BlockBackend *blk;
+    DriveInfo *dinfo;
+    Location loc;
+    bool orphans = false;
+
+    for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
+        dinfo = blk_legacy_dinfo(blk);
+        /*
+         * Ignore default drives, because we create certain default
+         * drives unconditionally, then leave them unclaimed.  Not the
+         * users fault.
+         * Ignore IF_VIRTIO, because it gets desugared into -device,
+         * so we can leave failing to -device.
+         * Ignore IF_NONE, because leaving unclaimed IF_NONE remains
+         * available for device_add is a feature.
+         */
+        if (dinfo->is_default || dinfo->type == IF_VIRTIO
+            || dinfo->type == IF_NONE) {
+            continue;
+        }
+        if (!blk_get_attached_dev(blk)) {
+            loc_push_none(&loc);
+            qemu_opts_loc_restore(dinfo->opts);
+            error_report("machine type does not support"
+                         " if=%s,bus=%d,unit=%d",
+                         if_name[dinfo->type], dinfo->bus, dinfo->unit);
+            loc_pop(&loc);
+            orphans = true;
+        }
+    }
+
+    if (orphans) {
+        exit(1);
+    }
+}
+
+DriveInfo *drive_get_by_index(BlockInterfaceType type, int index)
+{
+    return drive_get(type,
+                     drive_index_to_bus_id(type, index),
+                     drive_index_to_unit_id(type, index));
+}
+
+int drive_get_max_bus(BlockInterfaceType type)
+{
+    int max_bus;
+    BlockBackend *blk;
+    DriveInfo *dinfo;
+
+    max_bus = -1;
+    for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
+        dinfo = blk_legacy_dinfo(blk);
+        if (dinfo && dinfo->type == type && dinfo->bus > max_bus) {
+            max_bus = dinfo->bus;
+        }
+    }
+    return max_bus;
+}
+
+/* Get a block device.  This should only be used for single-drive devices
+   (e.g. SD/Floppy/MTD).  Multi-disk devices (scsi/ide) should use the
+   appropriate bus.  */
+DriveInfo *drive_get_next(BlockInterfaceType type)
+{
+    static int next_block_unit[IF_COUNT];
+
+    return drive_get(type, 0, next_block_unit[type]++);
+}
+
+static void bdrv_format_print(void *opaque, const char *name)
+{
+    qemu_printf(" %s", name);
+}
+
+typedef struct {
+    QEMUBH *bh;
+    BlockDriverState *bs;
+} BDRVPutRefBH;
+
+static int parse_block_error_action(const char *buf, bool is_read, Error **errp)
+{
+    if (!strcmp(buf, "ignore")) {
+        return BLOCKDEV_ON_ERROR_IGNORE;
+    } else if (!is_read && !strcmp(buf, "enospc")) {
+        return BLOCKDEV_ON_ERROR_ENOSPC;
+    } else if (!strcmp(buf, "stop")) {
+        return BLOCKDEV_ON_ERROR_STOP;
+    } else if (!strcmp(buf, "report")) {
+        return BLOCKDEV_ON_ERROR_REPORT;
+    } else {
+        error_setg(errp, "'%s' invalid %s error action",
+                   buf, is_read ? "read" : "write");
+        return -1;
+    }
+}
+
+static bool parse_stats_intervals(BlockAcctStats *stats, QList *intervals,
+                                  Error **errp)
+{
+    const QListEntry *entry;
+    for (entry = qlist_first(intervals); entry; entry = qlist_next(entry)) {
+        switch (qobject_type(entry->value)) {
+
+        case QTYPE_QSTRING: {
+            unsigned long long length;
+            const char *str = qstring_get_str(qobject_to(QString,
+                                                         entry->value));
+            if (parse_uint_full(str, &length, 10) == 0 &&
+                length > 0 && length <= UINT_MAX) {
+                block_acct_add_interval(stats, (unsigned) length);
+            } else {
+                error_setg(errp, "Invalid interval length: %s", str);
+                return false;
+            }
+            break;
+        }
+
+        case QTYPE_QNUM: {
+            int64_t length = qnum_get_int(qobject_to(QNum, entry->value));
+
+            if (length > 0 && length <= UINT_MAX) {
+                block_acct_add_interval(stats, (unsigned) length);
+            } else {
+                error_setg(errp, "Invalid interval length: %" PRId64, length);
+                return false;
+            }
+            break;
+        }
+
+        default:
+            error_setg(errp, "The specification of stats-intervals is invalid");
+            return false;
+        }
+    }
+    return true;
+}
+
+typedef enum { MEDIA_DISK, MEDIA_CDROM } DriveMediaType;
+
+/* All parameters but @opts are optional and may be set to NULL. */
+static void extract_common_blockdev_options(QemuOpts *opts, int *bdrv_flags,
+    const char **throttling_group, ThrottleConfig *throttle_cfg,
+    BlockdevDetectZeroesOptions *detect_zeroes, Error **errp)
+{
+    Error *local_error = NULL;
+    const char *aio;
+
+    if (bdrv_flags) {
+        if (qemu_opt_get_bool(opts, "copy-on-read", false)) {
+            *bdrv_flags |= BDRV_O_COPY_ON_READ;
+        }
+
+        if ((aio = qemu_opt_get(opts, "aio")) != NULL) {
+            if (bdrv_parse_aio(aio, bdrv_flags) < 0) {
+                error_setg(errp, "invalid aio option");
+                return;
+            }
+        }
+    }
+
+    /* disk I/O throttling */
+    if (throttling_group) {
+        *throttling_group = qemu_opt_get(opts, "throttling.group");
+    }
+
+    if (throttle_cfg) {
+        throttle_config_init(throttle_cfg);
+        throttle_cfg->buckets[THROTTLE_BPS_TOTAL].avg =
+            qemu_opt_get_number(opts, "throttling.bps-total", 0);
+        throttle_cfg->buckets[THROTTLE_BPS_READ].avg  =
+            qemu_opt_get_number(opts, "throttling.bps-read", 0);
+        throttle_cfg->buckets[THROTTLE_BPS_WRITE].avg =
+            qemu_opt_get_number(opts, "throttling.bps-write", 0);
+        throttle_cfg->buckets[THROTTLE_OPS_TOTAL].avg =
+            qemu_opt_get_number(opts, "throttling.iops-total", 0);
+        throttle_cfg->buckets[THROTTLE_OPS_READ].avg =
+            qemu_opt_get_number(opts, "throttling.iops-read", 0);
+        throttle_cfg->buckets[THROTTLE_OPS_WRITE].avg =
+            qemu_opt_get_number(opts, "throttling.iops-write", 0);
+
+        throttle_cfg->buckets[THROTTLE_BPS_TOTAL].max =
+            qemu_opt_get_number(opts, "throttling.bps-total-max", 0);
+        throttle_cfg->buckets[THROTTLE_BPS_READ].max  =
+            qemu_opt_get_number(opts, "throttling.bps-read-max", 0);
+        throttle_cfg->buckets[THROTTLE_BPS_WRITE].max =
+            qemu_opt_get_number(opts, "throttling.bps-write-max", 0);
+        throttle_cfg->buckets[THROTTLE_OPS_TOTAL].max =
+            qemu_opt_get_number(opts, "throttling.iops-total-max", 0);
+        throttle_cfg->buckets[THROTTLE_OPS_READ].max =
+            qemu_opt_get_number(opts, "throttling.iops-read-max", 0);
+        throttle_cfg->buckets[THROTTLE_OPS_WRITE].max =
+            qemu_opt_get_number(opts, "throttling.iops-write-max", 0);
+
+        throttle_cfg->buckets[THROTTLE_BPS_TOTAL].burst_length =
+            qemu_opt_get_number(opts, "throttling.bps-total-max-length", 1);
+        throttle_cfg->buckets[THROTTLE_BPS_READ].burst_length  =
+            qemu_opt_get_number(opts, "throttling.bps-read-max-length", 1);
+        throttle_cfg->buckets[THROTTLE_BPS_WRITE].burst_length =
+            qemu_opt_get_number(opts, "throttling.bps-write-max-length", 1);
+        throttle_cfg->buckets[THROTTLE_OPS_TOTAL].burst_length =
+            qemu_opt_get_number(opts, "throttling.iops-total-max-length", 1);
+        throttle_cfg->buckets[THROTTLE_OPS_READ].burst_length =
+            qemu_opt_get_number(opts, "throttling.iops-read-max-length", 1);
+        throttle_cfg->buckets[THROTTLE_OPS_WRITE].burst_length =
+            qemu_opt_get_number(opts, "throttling.iops-write-max-length", 1);
+
+        throttle_cfg->op_size =
+            qemu_opt_get_number(opts, "throttling.iops-size", 0);
+
+        if (!throttle_is_valid(throttle_cfg, errp)) {
+            return;
+        }
+    }
+
+    if (detect_zeroes) {
+        *detect_zeroes =
+            qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup,
+                            qemu_opt_get(opts, "detect-zeroes"),
+                            BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
+                            &local_error);
+        if (local_error) {
+            error_propagate(errp, local_error);
+            return;
+        }
+    }
+}
+
+/* Takes the ownership of bs_opts */
+static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
+                                   Error **errp)
+{
+    const char *buf;
+    int bdrv_flags = 0;
+    int on_read_error, on_write_error;
+    bool account_invalid, account_failed;
+    bool writethrough, read_only;
+    BlockBackend *blk;
+    BlockDriverState *bs;
+    ThrottleConfig cfg;
+    int snapshot = 0;
+    Error *error = NULL;
+    QemuOpts *opts;
+    QDict *interval_dict = NULL;
+    QList *interval_list = NULL;
+    const char *id;
+    BlockdevDetectZeroesOptions detect_zeroes =
+        BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF;
+    const char *throttling_group = NULL;
+
+    /* Check common options by copying from bs_opts to opts, all other options
+     * stay in bs_opts for processing by bdrv_open(). */
+    id = qdict_get_try_str(bs_opts, "id");
+    opts = qemu_opts_create(&qemu_common_drive_opts, id, 1, errp);
+    if (!opts) {
+        goto err_no_opts;
+    }
+
+    if (!qemu_opts_absorb_qdict(opts, bs_opts, errp)) {
+        goto early_err;
+    }
+
+    if (id) {
+        qdict_del(bs_opts, "id");
+    }
+
+    /* extract parameters */
+    snapshot = qemu_opt_get_bool(opts, "snapshot", 0);
+
+    account_invalid = qemu_opt_get_bool(opts, "stats-account-invalid", true);
+    account_failed = qemu_opt_get_bool(opts, "stats-account-failed", true);
+
+    writethrough = !qemu_opt_get_bool(opts, BDRV_OPT_CACHE_WB, true);
+
+    id = qemu_opts_id(opts);
+
+    qdict_extract_subqdict(bs_opts, &interval_dict, "stats-intervals.");
+    qdict_array_split(interval_dict, &interval_list);
+
+    if (qdict_size(interval_dict) != 0) {
+        error_setg(errp, "Invalid option stats-intervals.%s",
+                   qdict_first(interval_dict)->key);
+        goto early_err;
+    }
+
+    extract_common_blockdev_options(opts, &bdrv_flags, &throttling_group, &cfg,
+                                    &detect_zeroes, &error);
+    if (error) {
+        error_propagate(errp, error);
+        goto early_err;
+    }
+
+    if ((buf = qemu_opt_get(opts, "format")) != NULL) {
+        if (is_help_option(buf)) {
+            qemu_printf("Supported formats:");
+            bdrv_iterate_format(bdrv_format_print, NULL, false);
+            qemu_printf("\nSupported formats (read-only):");
+            bdrv_iterate_format(bdrv_format_print, NULL, true);
+            qemu_printf("\n");
+            goto early_err;
+        }
+
+        if (qdict_haskey(bs_opts, "driver")) {
+            error_setg(errp, "Cannot specify both 'driver' and 'format'");
+            goto early_err;
+        }
+        qdict_put_str(bs_opts, "driver", buf);
+    }
+
+    on_write_error = BLOCKDEV_ON_ERROR_ENOSPC;
+    if ((buf = qemu_opt_get(opts, "werror")) != NULL) {
+        on_write_error = parse_block_error_action(buf, 0, &error);
+        if (error) {
+            error_propagate(errp, error);
+            goto early_err;
+        }
+    }
+
+    on_read_error = BLOCKDEV_ON_ERROR_REPORT;
+    if ((buf = qemu_opt_get(opts, "rerror")) != NULL) {
+        on_read_error = parse_block_error_action(buf, 1, &error);
+        if (error) {
+            error_propagate(errp, error);
+            goto early_err;
+        }
+    }
+
+    if (snapshot) {
+        bdrv_flags |= BDRV_O_SNAPSHOT;
+    }
+
+    read_only = qemu_opt_get_bool(opts, BDRV_OPT_READ_ONLY, false);
+
+    /* init */
+    if ((!file || !*file) && !qdict_size(bs_opts)) {
+        BlockBackendRootState *blk_rs;
+
+        blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL);
+        blk_rs = blk_get_root_state(blk);
+        blk_rs->open_flags    = bdrv_flags | (read_only ? 0 : BDRV_O_RDWR);
+        blk_rs->detect_zeroes = detect_zeroes;
+
+        qobject_unref(bs_opts);
+    } else {
+        if (file && !*file) {
+            file = NULL;
+        }
+
+        /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
+         * with other callers) rather than what we want as the real defaults.
+         * Apply the defaults here instead. */
+        qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
+        qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
+        qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY,
+                              read_only ? "on" : "off");
+        qdict_set_default_str(bs_opts, BDRV_OPT_AUTO_READ_ONLY, "on");
+        assert((bdrv_flags & BDRV_O_CACHE_MASK) == 0);
+
+        if (runstate_check(RUN_STATE_INMIGRATE)) {
+            bdrv_flags |= BDRV_O_INACTIVE;
+        }
+
+        blk = blk_new_open(file, NULL, bs_opts, bdrv_flags, errp);
+        if (!blk) {
+            goto err_no_bs_opts;
+        }
+        bs = blk_bs(blk);
+
+        bs->detect_zeroes = detect_zeroes;
+
+        block_acct_setup(blk_get_stats(blk), account_invalid, account_failed);
+
+        if (!parse_stats_intervals(blk_get_stats(blk), interval_list, errp)) {
+            blk_unref(blk);
+            blk = NULL;
+            goto err_no_bs_opts;
+        }
+    }
+
+    /* disk I/O throttling */
+    if (throttle_enabled(&cfg)) {
+        if (!throttling_group) {
+            throttling_group = id;
+        }
+        blk_io_limits_enable(blk, throttling_group);
+        blk_set_io_limits(blk, &cfg);
+    }
+
+    blk_set_enable_write_cache(blk, !writethrough);
+    blk_set_on_error(blk, on_read_error, on_write_error);
+
+    if (!monitor_add_blk(blk, id, errp)) {
+        blk_unref(blk);
+        blk = NULL;
+        goto err_no_bs_opts;
+    }
+
+err_no_bs_opts:
+    qemu_opts_del(opts);
+    qobject_unref(interval_dict);
+    qobject_unref(interval_list);
+    return blk;
+
+early_err:
+    qemu_opts_del(opts);
+    qobject_unref(interval_dict);
+    qobject_unref(interval_list);
+err_no_opts:
+    qobject_unref(bs_opts);
+    return NULL;
+}
+
+/* Takes the ownership of bs_opts */
+BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp)
+{
+    int bdrv_flags = 0;
+
+    /* bdrv_open() defaults to the values in bdrv_flags (for compatibility
+     * with other callers) rather than what we want as the real defaults.
+     * Apply the defaults here instead. */
+    qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_DIRECT, "off");
+    qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off");
+    qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY, "off");
+
+    if (runstate_check(RUN_STATE_INMIGRATE)) {
+        bdrv_flags |= BDRV_O_INACTIVE;
+    }
+
+    return bdrv_open(NULL, NULL, bs_opts, bdrv_flags, errp);
+}
+
+void blockdev_close_all_bdrv_states(void)
+{
+    BlockDriverState *bs, *next_bs;
+
+    QTAILQ_FOREACH_SAFE(bs, &monitor_bdrv_states, monitor_list, next_bs) {
+        AioContext *ctx = bdrv_get_aio_context(bs);
+
+        aio_context_acquire(ctx);
+        bdrv_unref(bs);
+        aio_context_release(ctx);
+    }
+}
+
+/* Iterates over the list of monitor-owned BlockDriverStates */
+BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs)
+{
+    return bs ? QTAILQ_NEXT(bs, monitor_list)
+              : QTAILQ_FIRST(&monitor_bdrv_states);
+}
+
+static bool qemu_opt_rename(QemuOpts *opts, const char *from, const char *to,
+                            Error **errp)
+{
+    const char *value;
+
+    value = qemu_opt_get(opts, from);
+    if (value) {
+        if (qemu_opt_find(opts, to)) {
+            error_setg(errp, "'%s' and its alias '%s' can't be used at the "
+                       "same time", to, from);
+            return false;
+        }
+    }
+
+    /* rename all items in opts */
+    while ((value = qemu_opt_get(opts, from))) {
+        qemu_opt_set(opts, to, value, &error_abort);
+        qemu_opt_unset(opts, from);
+    }
+    return true;
+}
+
+QemuOptsList qemu_legacy_drive_opts = {
+    .name = "drive",
+    .head = QTAILQ_HEAD_INITIALIZER(qemu_legacy_drive_opts.head),
+    .desc = {
+        {
+            .name = "bus",
+            .type = QEMU_OPT_NUMBER,
+            .help = "bus number",
+        },{
+            .name = "unit",
+            .type = QEMU_OPT_NUMBER,
+            .help = "unit number (i.e. lun for scsi)",
+        },{
+            .name = "index",
+            .type = QEMU_OPT_NUMBER,
+            .help = "index number",
+        },{
+            .name = "media",
+            .type = QEMU_OPT_STRING,
+            .help = "media type (disk, cdrom)",
+        },{
+            .name = "if",
+            .type = QEMU_OPT_STRING,
+            .help = "interface (ide, scsi, sd, mtd, floppy, pflash, virtio)",
+        },{
+            .name = "file",
+            .type = QEMU_OPT_STRING,
+            .help = "file name",
+        },
+
+        /* Options that are passed on, but have special semantics with -drive */
+        {
+            .name = BDRV_OPT_READ_ONLY,
+            .type = QEMU_OPT_BOOL,
+            .help = "open drive file as read-only",
+        },{
+            .name = "rerror",
+            .type = QEMU_OPT_STRING,
+            .help = "read error action",
+        },{
+            .name = "werror",
+            .type = QEMU_OPT_STRING,
+            .help = "write error action",
+        },{
+            .name = "copy-on-read",
+            .type = QEMU_OPT_BOOL,
+            .help = "copy read data from backing file into image file",
+        },
+
+        { /* end of list */ }
+    },
+};
+
+DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type,
+                     Error **errp)
+{
+    const char *value;
+    BlockBackend *blk;
+    DriveInfo *dinfo = NULL;
+    QDict *bs_opts;
+    QemuOpts *legacy_opts;
+    DriveMediaType media = MEDIA_DISK;
+    BlockInterfaceType type;
+    int max_devs, bus_id, unit_id, index;
+    const char *werror, *rerror;
+    bool read_only = false;
+    bool copy_on_read;
+    const char *filename;
+    int i;
+
+    /* Change legacy command line options into QMP ones */
+    static const struct {
+        const char *from;
+        const char *to;
+    } opt_renames[] = {
+        { "iops",           "throttling.iops-total" },
+        { "iops_rd",        "throttling.iops-read" },
+        { "iops_wr",        "throttling.iops-write" },
+
+        { "bps",            "throttling.bps-total" },
+        { "bps_rd",         "throttling.bps-read" },
+        { "bps_wr",         "throttling.bps-write" },
+
+        { "iops_max",       "throttling.iops-total-max" },
+        { "iops_rd_max",    "throttling.iops-read-max" },
+        { "iops_wr_max",    "throttling.iops-write-max" },
+
+        { "bps_max",        "throttling.bps-total-max" },
+        { "bps_rd_max",     "throttling.bps-read-max" },
+        { "bps_wr_max",     "throttling.bps-write-max" },
+
+        { "iops_size",      "throttling.iops-size" },
+
+        { "group",          "throttling.group" },
+
+        { "readonly",       BDRV_OPT_READ_ONLY },
+    };
+
+    for (i = 0; i < ARRAY_SIZE(opt_renames); i++) {
+        if (!qemu_opt_rename(all_opts, opt_renames[i].from,
+                             opt_renames[i].to, errp)) {
+            return NULL;
+        }
+    }
+
+    value = qemu_opt_get(all_opts, "cache");
+    if (value) {
+        int flags = 0;
+        bool writethrough;
+
+        if (bdrv_parse_cache_mode(value, &flags, &writethrough) != 0) {
+            error_setg(errp, "invalid cache option");
+            return NULL;
+        }
+
+        /* Specific options take precedence */
+        if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_WB)) {
+            qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_WB,
+                              !writethrough, &error_abort);
+        }
+        if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_DIRECT)) {
+            qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_DIRECT,
+                              !!(flags & BDRV_O_NOCACHE), &error_abort);
+        }
+        if (!qemu_opt_get(all_opts, BDRV_OPT_CACHE_NO_FLUSH)) {
+            qemu_opt_set_bool(all_opts, BDRV_OPT_CACHE_NO_FLUSH,
+                              !!(flags & BDRV_O_NO_FLUSH), &error_abort);
+        }
+        qemu_opt_unset(all_opts, "cache");
+    }
+
+    /* Get a QDict for processing the options */
+    bs_opts = qdict_new();
+    qemu_opts_to_qdict(all_opts, bs_opts);
+
+    legacy_opts = qemu_opts_create(&qemu_legacy_drive_opts, NULL, 0,
+                                   &error_abort);
+    if (!qemu_opts_absorb_qdict(legacy_opts, bs_opts, errp)) {
+        goto fail;
+    }
+
+    /* Media type */
+    value = qemu_opt_get(legacy_opts, "media");
+    if (value) {
+        if (!strcmp(value, "disk")) {
+            media = MEDIA_DISK;
+        } else if (!strcmp(value, "cdrom")) {
+            media = MEDIA_CDROM;
+            read_only = true;
+        } else {
+            error_setg(errp, "'%s' invalid media", value);
+            goto fail;
+        }
+    }
+
+    /* copy-on-read is disabled with a warning for read-only devices */
+    read_only |= qemu_opt_get_bool(legacy_opts, BDRV_OPT_READ_ONLY, false);
+    copy_on_read = qemu_opt_get_bool(legacy_opts, "copy-on-read", false);
+
+    if (read_only && copy_on_read) {
+        warn_report("disabling copy-on-read on read-only drive");
+        copy_on_read = false;
+    }
+
+    qdict_put_str(bs_opts, BDRV_OPT_READ_ONLY, read_only ? "on" : "off");
+    qdict_put_str(bs_opts, "copy-on-read", copy_on_read ? "on" : "off");
+
+    /* Controller type */
+    value = qemu_opt_get(legacy_opts, "if");
+    if (value) {
+        for (type = 0;
+             type < IF_COUNT && strcmp(value, if_name[type]);
+             type++) {
+        }
+        if (type == IF_COUNT) {
+            error_setg(errp, "unsupported bus type '%s'", value);
+            goto fail;
+        }
+    } else {
+        type = block_default_type;
+    }
+
+    /* Device address specified by bus/unit or index.
+     * If none was specified, try to find the first free one. */
+    bus_id  = qemu_opt_get_number(legacy_opts, "bus", 0);
+    unit_id = qemu_opt_get_number(legacy_opts, "unit", -1);
+    index   = qemu_opt_get_number(legacy_opts, "index", -1);
+
+    max_devs = if_max_devs[type];
+
+    if (index != -1) {
+        if (bus_id != 0 || unit_id != -1) {
+            error_setg(errp, "index cannot be used with bus and unit");
+            goto fail;
+        }
+        bus_id = drive_index_to_bus_id(type, index);
+        unit_id = drive_index_to_unit_id(type, index);
+    }
+
+    if (unit_id == -1) {
+       unit_id = 0;
+       while (drive_get(type, bus_id, unit_id) != NULL) {
+           unit_id++;
+           if (max_devs && unit_id >= max_devs) {
+               unit_id -= max_devs;
+               bus_id++;
+           }
+       }
+    }
+
+    if (max_devs && unit_id >= max_devs) {
+        error_setg(errp, "unit %d too big (max is %d)", unit_id, max_devs - 1);
+        goto fail;
+    }
+
+    if (drive_get(type, bus_id, unit_id) != NULL) {
+        error_setg(errp, "drive with bus=%d, unit=%d (index=%d) exists",
+                   bus_id, unit_id, index);
+        goto fail;
+    }
+
+    /* no id supplied -> create one */
+    if (qemu_opts_id(all_opts) == NULL) {
+        char *new_id;
+        const char *mediastr = "";
+        if (type == IF_IDE || type == IF_SCSI) {
+            mediastr = (media == MEDIA_CDROM) ? "-cd" : "-hd";
+        }
+        if (max_devs) {
+            new_id = g_strdup_printf("%s%i%s%i", if_name[type], bus_id,
+                                     mediastr, unit_id);
+        } else {
+            new_id = g_strdup_printf("%s%s%i", if_name[type],
+                                     mediastr, unit_id);
+        }
+        qdict_put_str(bs_opts, "id", new_id);
+        g_free(new_id);
+    }
+
+    /* Add virtio block device */
+    if (type == IF_VIRTIO) {
+        QemuOpts *devopts;
+        devopts = qemu_opts_create(qemu_find_opts("device"), NULL, 0,
+                                   &error_abort);
+        qemu_opt_set(devopts, "driver", "virtio-blk", &error_abort);
+        qemu_opt_set(devopts, "drive", qdict_get_str(bs_opts, "id"),
+                     &error_abort);
+    }
+
+    filename = qemu_opt_get(legacy_opts, "file");
+
+    /* Check werror/rerror compatibility with if=... */
+    werror = qemu_opt_get(legacy_opts, "werror");
+    if (werror != NULL) {
+        if (type != IF_IDE && type != IF_SCSI && type != IF_VIRTIO &&
+            type != IF_NONE) {
+            error_setg(errp, "werror is not supported by this bus type");
+            goto fail;
+        }
+        qdict_put_str(bs_opts, "werror", werror);
+    }
+
+    rerror = qemu_opt_get(legacy_opts, "rerror");
+    if (rerror != NULL) {
+        if (type != IF_IDE && type != IF_VIRTIO && type != IF_SCSI &&
+            type != IF_NONE) {
+            error_setg(errp, "rerror is not supported by this bus type");
+            goto fail;
+        }
+        qdict_put_str(bs_opts, "rerror", rerror);
+    }
+
+    /* Actual block device init: Functionality shared with blockdev-add */
+    blk = blockdev_init(filename, bs_opts, errp);
+    bs_opts = NULL;
+    if (!blk) {
+        goto fail;
+    }
+
+    /* Create legacy DriveInfo */
+    dinfo = g_malloc0(sizeof(*dinfo));
+    dinfo->opts = all_opts;
+
+    dinfo->type = type;
+    dinfo->bus = bus_id;
+    dinfo->unit = unit_id;
+
+    blk_set_legacy_dinfo(blk, dinfo);
+
+    switch(type) {
+    case IF_IDE:
+    case IF_SCSI:
+    case IF_XEN:
+    case IF_NONE:
+        dinfo->media_cd = media == MEDIA_CDROM;
+        break;
+    default:
+        break;
+    }
+
+fail:
+    qemu_opts_del(legacy_opts);
+    qobject_unref(bs_opts);
+    return dinfo;
+}
+
+static BlockDriverState *qmp_get_root_bs(const char *name, Error **errp)
+{
+    BlockDriverState *bs;
+
+    bs = bdrv_lookup_bs(name, name, errp);
+    if (bs == NULL) {
+        return NULL;
+    }
+
+    if (!bdrv_is_root_node(bs)) {
+        error_setg(errp, "Need a root block node");
+        return NULL;
+    }
+
+    if (!bdrv_is_inserted(bs)) {
+        error_setg(errp, "Device has no medium");
+        return NULL;
+    }
+
+    return bs;
+}
+
+static void blockdev_do_action(TransactionAction *action, Error **errp)
+{
+    TransactionActionList list;
+
+    list.value = action;
+    list.next = NULL;
+    qmp_transaction(&list, false, NULL, errp);
+}
+
+void qmp_blockdev_snapshot_sync(bool has_device, const char *device,
+                                bool has_node_name, const char *node_name,
+                                const char *snapshot_file,
+                                bool has_snapshot_node_name,
+                                const char *snapshot_node_name,
+                                bool has_format, const char *format,
+                                bool has_mode, NewImageMode mode, Error **errp)
+{
+    BlockdevSnapshotSync snapshot = {
+        .has_device = has_device,
+        .device = (char *) device,
+        .has_node_name = has_node_name,
+        .node_name = (char *) node_name,
+        .snapshot_file = (char *) snapshot_file,
+        .has_snapshot_node_name = has_snapshot_node_name,
+        .snapshot_node_name = (char *) snapshot_node_name,
+        .has_format = has_format,
+        .format = (char *) format,
+        .has_mode = has_mode,
+        .mode = mode,
+    };
+    TransactionAction action = {
+        .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC,
+        .u.blockdev_snapshot_sync.data = &snapshot,
+    };
+    blockdev_do_action(&action, errp);
+}
+
+void qmp_blockdev_snapshot(const char *node, const char *overlay,
+                           Error **errp)
+{
+    BlockdevSnapshot snapshot_data = {
+        .node = (char *) node,
+        .overlay = (char *) overlay
+    };
+    TransactionAction action = {
+        .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT,
+        .u.blockdev_snapshot.data = &snapshot_data,
+    };
+    blockdev_do_action(&action, errp);
+}
+
+void qmp_blockdev_snapshot_internal_sync(const char *device,
+                                         const char *name,
+                                         Error **errp)
+{
+    BlockdevSnapshotInternal snapshot = {
+        .device = (char *) device,
+        .name = (char *) name
+    };
+    TransactionAction action = {
+        .type = TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC,
+        .u.blockdev_snapshot_internal_sync.data = &snapshot,
+    };
+    blockdev_do_action(&action, errp);
+}
+
+SnapshotInfo *qmp_blockdev_snapshot_delete_internal_sync(const char *device,
+                                                         bool has_id,
+                                                         const char *id,
+                                                         bool has_name,
+                                                         const char *name,
+                                                         Error **errp)
+{
+    BlockDriverState *bs;
+    AioContext *aio_context;
+    QEMUSnapshotInfo sn;
+    Error *local_err = NULL;
+    SnapshotInfo *info = NULL;
+    int ret;
+
+    bs = qmp_get_root_bs(device, errp);
+    if (!bs) {
+        return NULL;
+    }
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    if (!has_id) {
+        id = NULL;
+    }
+
+    if (!has_name) {
+        name = NULL;
+    }
+
+    if (!id && !name) {
+        error_setg(errp, "Name or id must be provided");
+        goto out_aio_context;
+    }
+
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, errp)) {
+        goto out_aio_context;
+    }
+
+    ret = bdrv_snapshot_find_by_id_and_name(bs, id, name, &sn, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto out_aio_context;
+    }
+    if (!ret) {
+        error_setg(errp,
+                   "Snapshot with id '%s' and name '%s' does not exist on "
+                   "device '%s'",
+                   STR_OR_NULL(id), STR_OR_NULL(name), device);
+        goto out_aio_context;
+    }
+
+    bdrv_snapshot_delete(bs, id, name, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto out_aio_context;
+    }
+
+    aio_context_release(aio_context);
+
+    info = g_new0(SnapshotInfo, 1);
+    info->id = g_strdup(sn.id_str);
+    info->name = g_strdup(sn.name);
+    info->date_nsec = sn.date_nsec;
+    info->date_sec = sn.date_sec;
+    info->vm_state_size = sn.vm_state_size;
+    info->vm_clock_nsec = sn.vm_clock_nsec % 1000000000;
+    info->vm_clock_sec = sn.vm_clock_nsec / 1000000000;
+    if (sn.icount != -1ULL) {
+        info->icount = sn.icount;
+        info->has_icount = true;
+    }
+
+    return info;
+
+out_aio_context:
+    aio_context_release(aio_context);
+    return NULL;
+}
+
+/* New and old BlockDriverState structs for atomic group operations */
+
+typedef struct BlkActionState BlkActionState;
+
+/**
+ * BlkActionOps:
+ * Table of operations that define an Action.
+ *
+ * @instance_size: Size of state struct, in bytes.
+ * @prepare: Prepare the work, must NOT be NULL.
+ * @commit: Commit the changes, can be NULL.
+ * @abort: Abort the changes on fail, can be NULL.
+ * @clean: Clean up resources after all transaction actions have called
+ *         commit() or abort(). Can be NULL.
+ *
+ * Only prepare() may fail. In a single transaction, only one of commit() or
+ * abort() will be called. clean() will always be called if it is present.
+ */
+typedef struct BlkActionOps {
+    size_t instance_size;
+    void (*prepare)(BlkActionState *common, Error **errp);
+    void (*commit)(BlkActionState *common);
+    void (*abort)(BlkActionState *common);
+    void (*clean)(BlkActionState *common);
+} BlkActionOps;
+
+/**
+ * BlkActionState:
+ * Describes one Action's state within a Transaction.
+ *
+ * @action: QAPI-defined enum identifying which Action to perform.
+ * @ops: Table of ActionOps this Action can perform.
+ * @block_job_txn: Transaction which this action belongs to.
+ * @entry: List membership for all Actions in this Transaction.
+ *
+ * This structure must be arranged as first member in a subclassed type,
+ * assuming that the compiler will also arrange it to the same offsets as the
+ * base class.
+ */
+struct BlkActionState {
+    TransactionAction *action;
+    const BlkActionOps *ops;
+    JobTxn *block_job_txn;
+    TransactionProperties *txn_props;
+    QTAILQ_ENTRY(BlkActionState) entry;
+};
+
+/* internal snapshot private data */
+typedef struct InternalSnapshotState {
+    BlkActionState common;
+    BlockDriverState *bs;
+    QEMUSnapshotInfo sn;
+    bool created;
+} InternalSnapshotState;
+
+
+static int action_check_completion_mode(BlkActionState *s, Error **errp)
+{
+    if (s->txn_props->completion_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
+        error_setg(errp,
+                   "Action '%s' does not support Transaction property "
+                   "completion-mode = %s",
+                   TransactionActionKind_str(s->action->type),
+                   ActionCompletionMode_str(s->txn_props->completion_mode));
+        return -1;
+    }
+    return 0;
+}
+
+static void internal_snapshot_prepare(BlkActionState *common,
+                                      Error **errp)
+{
+    Error *local_err = NULL;
+    const char *device;
+    const char *name;
+    BlockDriverState *bs;
+    QEMUSnapshotInfo old_sn, *sn;
+    bool ret;
+    qemu_timeval tv;
+    BlockdevSnapshotInternal *internal;
+    InternalSnapshotState *state;
+    AioContext *aio_context;
+    int ret1;
+
+    g_assert(common->action->type ==
+             TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC);
+    internal = common->action->u.blockdev_snapshot_internal_sync.data;
+    state = DO_UPCAST(InternalSnapshotState, common, common);
+
+    /* 1. parse input */
+    device = internal->device;
+    name = internal->name;
+
+    /* 2. check for validation */
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    bs = qmp_get_root_bs(device, errp);
+    if (!bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    state->bs = bs;
+
+    /* Paired with .clean() */
+    bdrv_drained_begin(bs);
+
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, errp)) {
+        goto out;
+    }
+
+    if (bdrv_is_read_only(bs)) {
+        error_setg(errp, "Device '%s' is read only", device);
+        goto out;
+    }
+
+    if (!bdrv_can_snapshot(bs)) {
+        error_setg(errp, "Block format '%s' used by device '%s' "
+                   "does not support internal snapshots",
+                   bs->drv->format_name, device);
+        goto out;
+    }
+
+    if (!strlen(name)) {
+        error_setg(errp, "Name is empty");
+        goto out;
+    }
+
+    /* check whether a snapshot with name exist */
+    ret = bdrv_snapshot_find_by_id_and_name(bs, NULL, name, &old_sn,
+                                            &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto out;
+    } else if (ret) {
+        error_setg(errp,
+                   "Snapshot with name '%s' already exists on device '%s'",
+                   name, device);
+        goto out;
+    }
+
+    /* 3. take the snapshot */
+    sn = &state->sn;
+    pstrcpy(sn->name, sizeof(sn->name), name);
+    qemu_gettimeofday(&tv);
+    sn->date_sec = tv.tv_sec;
+    sn->date_nsec = tv.tv_usec * 1000;
+    sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    if (replay_mode != REPLAY_MODE_NONE) {
+        sn->icount = replay_get_current_icount();
+    } else {
+        sn->icount = -1ULL;
+    }
+
+    ret1 = bdrv_snapshot_create(bs, sn);
+    if (ret1 < 0) {
+        error_setg_errno(errp, -ret1,
+                         "Failed to create snapshot '%s' on device '%s'",
+                         name, device);
+        goto out;
+    }
+
+    /* 4. succeed, mark a snapshot is created */
+    state->created = true;
+
+out:
+    aio_context_release(aio_context);
+}
+
+static void internal_snapshot_abort(BlkActionState *common)
+{
+    InternalSnapshotState *state =
+                             DO_UPCAST(InternalSnapshotState, common, common);
+    BlockDriverState *bs = state->bs;
+    QEMUSnapshotInfo *sn = &state->sn;
+    AioContext *aio_context;
+    Error *local_error = NULL;
+
+    if (!state->created) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(state->bs);
+    aio_context_acquire(aio_context);
+
+    if (bdrv_snapshot_delete(bs, sn->id_str, sn->name, &local_error) < 0) {
+        error_reportf_err(local_error,
+                          "Failed to delete snapshot with id '%s' and "
+                          "name '%s' on device '%s' in abort: ",
+                          sn->id_str, sn->name,
+                          bdrv_get_device_name(bs));
+    }
+
+    aio_context_release(aio_context);
+}
+
+static void internal_snapshot_clean(BlkActionState *common)
+{
+    InternalSnapshotState *state = DO_UPCAST(InternalSnapshotState,
+                                             common, common);
+    AioContext *aio_context;
+
+    if (!state->bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(state->bs);
+    aio_context_acquire(aio_context);
+
+    bdrv_drained_end(state->bs);
+
+    aio_context_release(aio_context);
+}
+
+/* external snapshot private data */
+typedef struct ExternalSnapshotState {
+    BlkActionState common;
+    BlockDriverState *old_bs;
+    BlockDriverState *new_bs;
+    bool overlay_appended;
+} ExternalSnapshotState;
+
+static void external_snapshot_prepare(BlkActionState *common,
+                                      Error **errp)
+{
+    int ret;
+    int flags = 0;
+    QDict *options = NULL;
+    Error *local_err = NULL;
+    /* Device and node name of the image to generate the snapshot from */
+    const char *device;
+    const char *node_name;
+    /* Reference to the new image (for 'blockdev-snapshot') */
+    const char *snapshot_ref;
+    /* File name of the new image (for 'blockdev-snapshot-sync') */
+    const char *new_image_file;
+    ExternalSnapshotState *state =
+                             DO_UPCAST(ExternalSnapshotState, common, common);
+    TransactionAction *action = common->action;
+    AioContext *aio_context;
+    uint64_t perm, shared;
+
+    /* 'blockdev-snapshot' and 'blockdev-snapshot-sync' have similar
+     * purpose but a different set of parameters */
+    switch (action->type) {
+    case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT:
+        {
+            BlockdevSnapshot *s = action->u.blockdev_snapshot.data;
+            device = s->node;
+            node_name = s->node;
+            new_image_file = NULL;
+            snapshot_ref = s->overlay;
+        }
+        break;
+    case TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC:
+        {
+            BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
+            device = s->has_device ? s->device : NULL;
+            node_name = s->has_node_name ? s->node_name : NULL;
+            new_image_file = s->snapshot_file;
+            snapshot_ref = NULL;
+        }
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    /* start processing */
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    state->old_bs = bdrv_lookup_bs(device, node_name, errp);
+    if (!state->old_bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(state->old_bs);
+    aio_context_acquire(aio_context);
+
+    /* Paired with .clean() */
+    bdrv_drained_begin(state->old_bs);
+
+    if (!bdrv_is_inserted(state->old_bs)) {
+        error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, device);
+        goto out;
+    }
+
+    if (bdrv_op_is_blocked(state->old_bs,
+                           BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, errp)) {
+        goto out;
+    }
+
+    if (!bdrv_is_read_only(state->old_bs)) {
+        if (bdrv_flush(state->old_bs)) {
+            error_setg(errp, QERR_IO_ERROR);
+            goto out;
+        }
+    }
+
+    if (action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC) {
+        BlockdevSnapshotSync *s = action->u.blockdev_snapshot_sync.data;
+        const char *format = s->has_format ? s->format : "qcow2";
+        enum NewImageMode mode;
+        const char *snapshot_node_name =
+            s->has_snapshot_node_name ? s->snapshot_node_name : NULL;
+
+        if (node_name && !snapshot_node_name) {
+            error_setg(errp, "New overlay node-name missing");
+            goto out;
+        }
+
+        if (snapshot_node_name &&
+            bdrv_lookup_bs(snapshot_node_name, snapshot_node_name, NULL)) {
+            error_setg(errp, "New overlay node-name already in use");
+            goto out;
+        }
+
+        flags = state->old_bs->open_flags;
+        flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_COPY_ON_READ);
+        flags |= BDRV_O_NO_BACKING;
+
+        /* create new image w/backing file */
+        mode = s->has_mode ? s->mode : NEW_IMAGE_MODE_ABSOLUTE_PATHS;
+        if (mode != NEW_IMAGE_MODE_EXISTING) {
+            int64_t size = bdrv_getlength(state->old_bs);
+            if (size < 0) {
+                error_setg_errno(errp, -size, "bdrv_getlength failed");
+                goto out;
+            }
+            bdrv_refresh_filename(state->old_bs);
+            bdrv_img_create(new_image_file, format,
+                            state->old_bs->filename,
+                            state->old_bs->drv->format_name,
+                            NULL, size, flags, false, &local_err);
+            if (local_err) {
+                error_propagate(errp, local_err);
+                goto out;
+            }
+        }
+
+        options = qdict_new();
+        if (snapshot_node_name) {
+            qdict_put_str(options, "node-name", snapshot_node_name);
+        }
+        qdict_put_str(options, "driver", format);
+    }
+
+    state->new_bs = bdrv_open(new_image_file, snapshot_ref, options, flags,
+                              errp);
+    /* We will manually add the backing_hd field to the bs later */
+    if (!state->new_bs) {
+        goto out;
+    }
+
+    /*
+     * Allow attaching a backing file to an overlay that's already in use only
+     * if the parents don't assume that they are already seeing a valid image.
+     * (Specifically, allow it as a mirror target, which is write-only access.)
+     */
+    bdrv_get_cumulative_perm(state->new_bs, &perm, &shared);
+    if (perm & BLK_PERM_CONSISTENT_READ) {
+        error_setg(errp, "The overlay is already in use");
+        goto out;
+    }
+
+    if (state->new_bs->drv->is_filter) {
+        error_setg(errp, "Filters cannot be used as overlays");
+        goto out;
+    }
+
+    if (bdrv_cow_child(state->new_bs)) {
+        error_setg(errp, "The overlay already has a backing image");
+        goto out;
+    }
+
+    if (!state->new_bs->drv->supports_backing) {
+        error_setg(errp, "The overlay does not support backing images");
+        goto out;
+    }
+
+    ret = bdrv_append(state->new_bs, state->old_bs, errp);
+    if (ret < 0) {
+        goto out;
+    }
+    state->overlay_appended = true;
+
+out:
+    aio_context_release(aio_context);
+}
+
+static void external_snapshot_commit(BlkActionState *common)
+{
+    ExternalSnapshotState *state =
+                             DO_UPCAST(ExternalSnapshotState, common, common);
+    AioContext *aio_context;
+
+    aio_context = bdrv_get_aio_context(state->old_bs);
+    aio_context_acquire(aio_context);
+
+    /* We don't need (or want) to use the transactional
+     * bdrv_reopen_multiple() across all the entries at once, because we
+     * don't want to abort all of them if one of them fails the reopen */
+    if (!qatomic_read(&state->old_bs->copy_on_read)) {
+        bdrv_reopen_set_read_only(state->old_bs, true, NULL);
+    }
+
+    aio_context_release(aio_context);
+}
+
+static void external_snapshot_abort(BlkActionState *common)
+{
+    ExternalSnapshotState *state =
+                             DO_UPCAST(ExternalSnapshotState, common, common);
+    if (state->new_bs) {
+        if (state->overlay_appended) {
+            AioContext *aio_context;
+            AioContext *tmp_context;
+            int ret;
+
+            aio_context = bdrv_get_aio_context(state->old_bs);
+            aio_context_acquire(aio_context);
+
+            bdrv_ref(state->old_bs);   /* we can't let bdrv_set_backind_hd()
+                                          close state->old_bs; we need it */
+            bdrv_set_backing_hd(state->new_bs, NULL, &error_abort);
+
+            /*
+             * The call to bdrv_set_backing_hd() above returns state->old_bs to
+             * the main AioContext. As we're still going to be using it, return
+             * it to the AioContext it was before.
+             */
+            tmp_context = bdrv_get_aio_context(state->old_bs);
+            if (aio_context != tmp_context) {
+                aio_context_release(aio_context);
+                aio_context_acquire(tmp_context);
+
+                ret = bdrv_try_set_aio_context(state->old_bs,
+                                               aio_context, NULL);
+                assert(ret == 0);
+
+                aio_context_release(tmp_context);
+                aio_context_acquire(aio_context);
+            }
+
+            bdrv_replace_node(state->new_bs, state->old_bs, &error_abort);
+            bdrv_unref(state->old_bs); /* bdrv_replace_node() ref'ed old_bs */
+
+            aio_context_release(aio_context);
+        }
+    }
+}
+
+static void external_snapshot_clean(BlkActionState *common)
+{
+    ExternalSnapshotState *state =
+                             DO_UPCAST(ExternalSnapshotState, common, common);
+    AioContext *aio_context;
+
+    if (!state->old_bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(state->old_bs);
+    aio_context_acquire(aio_context);
+
+    bdrv_drained_end(state->old_bs);
+    bdrv_unref(state->new_bs);
+
+    aio_context_release(aio_context);
+}
+
+typedef struct DriveBackupState {
+    BlkActionState common;
+    BlockDriverState *bs;
+    BlockJob *job;
+} DriveBackupState;
+
+static BlockJob *do_backup_common(BackupCommon *backup,
+                                  BlockDriverState *bs,
+                                  BlockDriverState *target_bs,
+                                  AioContext *aio_context,
+                                  JobTxn *txn, Error **errp);
+
+static void drive_backup_prepare(BlkActionState *common, Error **errp)
+{
+    DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
+    DriveBackup *backup;
+    BlockDriverState *bs;
+    BlockDriverState *target_bs;
+    BlockDriverState *source = NULL;
+    AioContext *aio_context;
+    AioContext *old_context;
+    QDict *options;
+    Error *local_err = NULL;
+    int flags;
+    int64_t size;
+    bool set_backing_hd = false;
+    int ret;
+
+    assert(common->action->type == TRANSACTION_ACTION_KIND_DRIVE_BACKUP);
+    backup = common->action->u.drive_backup.data;
+
+    if (!backup->has_mode) {
+        backup->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
+    }
+
+    bs = bdrv_lookup_bs(backup->device, backup->device, errp);
+    if (!bs) {
+        return;
+    }
+
+    if (!bs->drv) {
+        error_setg(errp, "Device has no medium");
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    state->bs = bs;
+    /* Paired with .clean() */
+    bdrv_drained_begin(bs);
+
+    if (!backup->has_format) {
+        backup->format = backup->mode == NEW_IMAGE_MODE_EXISTING ?
+                         NULL : (char *) bs->drv->format_name;
+    }
+
+    /* Early check to avoid creating target */
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
+        goto out;
+    }
+
+    flags = bs->open_flags | BDRV_O_RDWR;
+
+    /*
+     * See if we have a backing HD we can use to create our new image
+     * on top of.
+     */
+    if (backup->sync == MIRROR_SYNC_MODE_TOP) {
+        /*
+         * Backup will not replace the source by the target, so none
+         * of the filters skipped here will be removed (in contrast to
+         * mirror).  Therefore, we can skip all of them when looking
+         * for the first COW relationship.
+         */
+        source = bdrv_cow_bs(bdrv_skip_filters(bs));
+        if (!source) {
+            backup->sync = MIRROR_SYNC_MODE_FULL;
+        }
+    }
+    if (backup->sync == MIRROR_SYNC_MODE_NONE) {
+        source = bs;
+        flags |= BDRV_O_NO_BACKING;
+        set_backing_hd = true;
+    }
+
+    size = bdrv_getlength(bs);
+    if (size < 0) {
+        error_setg_errno(errp, -size, "bdrv_getlength failed");
+        goto out;
+    }
+
+    if (backup->mode != NEW_IMAGE_MODE_EXISTING) {
+        assert(backup->format);
+        if (source) {
+            /* Implicit filters should not appear in the filename */
+            BlockDriverState *explicit_backing =
+                bdrv_skip_implicit_filters(source);
+
+            bdrv_refresh_filename(explicit_backing);
+            bdrv_img_create(backup->target, backup->format,
+                            explicit_backing->filename,
+                            explicit_backing->drv->format_name, NULL,
+                            size, flags, false, &local_err);
+        } else {
+            bdrv_img_create(backup->target, backup->format, NULL, NULL, NULL,
+                            size, flags, false, &local_err);
+        }
+    }
+
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    options = qdict_new();
+    qdict_put_str(options, "discard", "unmap");
+    qdict_put_str(options, "detect-zeroes", "unmap");
+    if (backup->format) {
+        qdict_put_str(options, "driver", backup->format);
+    }
+
+    target_bs = bdrv_open(backup->target, NULL, options, flags, errp);
+    if (!target_bs) {
+        goto out;
+    }
+
+    /* Honor bdrv_try_set_aio_context() context acquisition requirements. */
+    old_context = bdrv_get_aio_context(target_bs);
+    aio_context_release(aio_context);
+    aio_context_acquire(old_context);
+
+    ret = bdrv_try_set_aio_context(target_bs, aio_context, errp);
+    if (ret < 0) {
+        bdrv_unref(target_bs);
+        aio_context_release(old_context);
+        return;
+    }
+
+    aio_context_release(old_context);
+    aio_context_acquire(aio_context);
+
+    if (set_backing_hd) {
+        if (bdrv_set_backing_hd(target_bs, source, errp) < 0) {
+            goto unref;
+        }
+    }
+
+    state->job = do_backup_common(qapi_DriveBackup_base(backup),
+                                  bs, target_bs, aio_context,
+                                  common->block_job_txn, errp);
+
+unref:
+    bdrv_unref(target_bs);
+out:
+    aio_context_release(aio_context);
+}
+
+static void drive_backup_commit(BlkActionState *common)
+{
+    DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
+    AioContext *aio_context;
+
+    aio_context = bdrv_get_aio_context(state->bs);
+    aio_context_acquire(aio_context);
+
+    assert(state->job);
+    job_start(&state->job->job);
+
+    aio_context_release(aio_context);
+}
+
+static void drive_backup_abort(BlkActionState *common)
+{
+    DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
+
+    if (state->job) {
+        AioContext *aio_context;
+
+        aio_context = bdrv_get_aio_context(state->bs);
+        aio_context_acquire(aio_context);
+
+        job_cancel_sync(&state->job->job, true);
+
+        aio_context_release(aio_context);
+    }
+}
+
+static void drive_backup_clean(BlkActionState *common)
+{
+    DriveBackupState *state = DO_UPCAST(DriveBackupState, common, common);
+    AioContext *aio_context;
+
+    if (!state->bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(state->bs);
+    aio_context_acquire(aio_context);
+
+    bdrv_drained_end(state->bs);
+
+    aio_context_release(aio_context);
+}
+
+typedef struct BlockdevBackupState {
+    BlkActionState common;
+    BlockDriverState *bs;
+    BlockJob *job;
+} BlockdevBackupState;
+
+static void blockdev_backup_prepare(BlkActionState *common, Error **errp)
+{
+    BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
+    BlockdevBackup *backup;
+    BlockDriverState *bs;
+    BlockDriverState *target_bs;
+    AioContext *aio_context;
+    AioContext *old_context;
+    int ret;
+
+    assert(common->action->type == TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP);
+    backup = common->action->u.blockdev_backup.data;
+
+    bs = bdrv_lookup_bs(backup->device, backup->device, errp);
+    if (!bs) {
+        return;
+    }
+
+    target_bs = bdrv_lookup_bs(backup->target, backup->target, errp);
+    if (!target_bs) {
+        return;
+    }
+
+    /* Honor bdrv_try_set_aio_context() context acquisition requirements. */
+    aio_context = bdrv_get_aio_context(bs);
+    old_context = bdrv_get_aio_context(target_bs);
+    aio_context_acquire(old_context);
+
+    ret = bdrv_try_set_aio_context(target_bs, aio_context, errp);
+    if (ret < 0) {
+        aio_context_release(old_context);
+        return;
+    }
+
+    aio_context_release(old_context);
+    aio_context_acquire(aio_context);
+    state->bs = bs;
+
+    /* Paired with .clean() */
+    bdrv_drained_begin(state->bs);
+
+    state->job = do_backup_common(qapi_BlockdevBackup_base(backup),
+                                  bs, target_bs, aio_context,
+                                  common->block_job_txn, errp);
+
+    aio_context_release(aio_context);
+}
+
+static void blockdev_backup_commit(BlkActionState *common)
+{
+    BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
+    AioContext *aio_context;
+
+    aio_context = bdrv_get_aio_context(state->bs);
+    aio_context_acquire(aio_context);
+
+    assert(state->job);
+    job_start(&state->job->job);
+
+    aio_context_release(aio_context);
+}
+
+static void blockdev_backup_abort(BlkActionState *common)
+{
+    BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
+
+    if (state->job) {
+        AioContext *aio_context;
+
+        aio_context = bdrv_get_aio_context(state->bs);
+        aio_context_acquire(aio_context);
+
+        job_cancel_sync(&state->job->job, true);
+
+        aio_context_release(aio_context);
+    }
+}
+
+static void blockdev_backup_clean(BlkActionState *common)
+{
+    BlockdevBackupState *state = DO_UPCAST(BlockdevBackupState, common, common);
+    AioContext *aio_context;
+
+    if (!state->bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(state->bs);
+    aio_context_acquire(aio_context);
+
+    bdrv_drained_end(state->bs);
+
+    aio_context_release(aio_context);
+}
+
+typedef struct BlockDirtyBitmapState {
+    BlkActionState common;
+    BdrvDirtyBitmap *bitmap;
+    BlockDriverState *bs;
+    HBitmap *backup;
+    bool prepared;
+    bool was_enabled;
+} BlockDirtyBitmapState;
+
+static void block_dirty_bitmap_add_prepare(BlkActionState *common,
+                                           Error **errp)
+{
+    Error *local_err = NULL;
+    BlockDirtyBitmapAdd *action;
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    action = common->action->u.block_dirty_bitmap_add.data;
+    /* AIO context taken and released within qmp_block_dirty_bitmap_add */
+    qmp_block_dirty_bitmap_add(action->node, action->name,
+                               action->has_granularity, action->granularity,
+                               action->has_persistent, action->persistent,
+                               action->has_disabled, action->disabled,
+                               &local_err);
+
+    if (!local_err) {
+        state->prepared = true;
+    } else {
+        error_propagate(errp, local_err);
+    }
+}
+
+static void block_dirty_bitmap_add_abort(BlkActionState *common)
+{
+    BlockDirtyBitmapAdd *action;
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    action = common->action->u.block_dirty_bitmap_add.data;
+    /* Should not be able to fail: IF the bitmap was added via .prepare(),
+     * then the node reference and bitmap name must have been valid.
+     */
+    if (state->prepared) {
+        qmp_block_dirty_bitmap_remove(action->node, action->name, &error_abort);
+    }
+}
+
+static void block_dirty_bitmap_clear_prepare(BlkActionState *common,
+                                             Error **errp)
+{
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+    BlockDirtyBitmap *action;
+
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    action = common->action->u.block_dirty_bitmap_clear.data;
+    state->bitmap = block_dirty_bitmap_lookup(action->node,
+                                              action->name,
+                                              &state->bs,
+                                              errp);
+    if (!state->bitmap) {
+        return;
+    }
+
+    if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_DEFAULT, errp)) {
+        return;
+    }
+
+    bdrv_clear_dirty_bitmap(state->bitmap, &state->backup);
+}
+
+static void block_dirty_bitmap_restore(BlkActionState *common)
+{
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (state->backup) {
+        bdrv_restore_dirty_bitmap(state->bitmap, state->backup);
+    }
+}
+
+static void block_dirty_bitmap_free_backup(BlkActionState *common)
+{
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    hbitmap_free(state->backup);
+}
+
+static void block_dirty_bitmap_enable_prepare(BlkActionState *common,
+                                              Error **errp)
+{
+    BlockDirtyBitmap *action;
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    action = common->action->u.block_dirty_bitmap_enable.data;
+    state->bitmap = block_dirty_bitmap_lookup(action->node,
+                                              action->name,
+                                              NULL,
+                                              errp);
+    if (!state->bitmap) {
+        return;
+    }
+
+    if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
+        return;
+    }
+
+    state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
+    bdrv_enable_dirty_bitmap(state->bitmap);
+}
+
+static void block_dirty_bitmap_enable_abort(BlkActionState *common)
+{
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (!state->was_enabled) {
+        bdrv_disable_dirty_bitmap(state->bitmap);
+    }
+}
+
+static void block_dirty_bitmap_disable_prepare(BlkActionState *common,
+                                               Error **errp)
+{
+    BlockDirtyBitmap *action;
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    action = common->action->u.block_dirty_bitmap_disable.data;
+    state->bitmap = block_dirty_bitmap_lookup(action->node,
+                                              action->name,
+                                              NULL,
+                                              errp);
+    if (!state->bitmap) {
+        return;
+    }
+
+    if (bdrv_dirty_bitmap_check(state->bitmap, BDRV_BITMAP_ALLOW_RO, errp)) {
+        return;
+    }
+
+    state->was_enabled = bdrv_dirty_bitmap_enabled(state->bitmap);
+    bdrv_disable_dirty_bitmap(state->bitmap);
+}
+
+static void block_dirty_bitmap_disable_abort(BlkActionState *common)
+{
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (state->was_enabled) {
+        bdrv_enable_dirty_bitmap(state->bitmap);
+    }
+}
+
+static void block_dirty_bitmap_merge_prepare(BlkActionState *common,
+                                             Error **errp)
+{
+    BlockDirtyBitmapMerge *action;
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    action = common->action->u.block_dirty_bitmap_merge.data;
+
+    state->bitmap = block_dirty_bitmap_merge(action->node, action->target,
+                                             action->bitmaps, &state->backup,
+                                             errp);
+}
+
+static void block_dirty_bitmap_remove_prepare(BlkActionState *common,
+                                              Error **errp)
+{
+    BlockDirtyBitmap *action;
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (action_check_completion_mode(common, errp) < 0) {
+        return;
+    }
+
+    action = common->action->u.block_dirty_bitmap_remove.data;
+
+    state->bitmap = block_dirty_bitmap_remove(action->node, action->name,
+                                              false, &state->bs, errp);
+    if (state->bitmap) {
+        bdrv_dirty_bitmap_skip_store(state->bitmap, true);
+        bdrv_dirty_bitmap_set_busy(state->bitmap, true);
+    }
+}
+
+static void block_dirty_bitmap_remove_abort(BlkActionState *common)
+{
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    if (state->bitmap) {
+        bdrv_dirty_bitmap_skip_store(state->bitmap, false);
+        bdrv_dirty_bitmap_set_busy(state->bitmap, false);
+    }
+}
+
+static void block_dirty_bitmap_remove_commit(BlkActionState *common)
+{
+    BlockDirtyBitmapState *state = DO_UPCAST(BlockDirtyBitmapState,
+                                             common, common);
+
+    bdrv_dirty_bitmap_set_busy(state->bitmap, false);
+    bdrv_release_dirty_bitmap(state->bitmap);
+}
+
+static void abort_prepare(BlkActionState *common, Error **errp)
+{
+    error_setg(errp, "Transaction aborted using Abort action");
+}
+
+static void abort_commit(BlkActionState *common)
+{
+    g_assert_not_reached(); /* this action never succeeds */
+}
+
+static const BlkActionOps actions[] = {
+    [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT] = {
+        .instance_size = sizeof(ExternalSnapshotState),
+        .prepare  = external_snapshot_prepare,
+        .commit   = external_snapshot_commit,
+        .abort = external_snapshot_abort,
+        .clean = external_snapshot_clean,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_SYNC] = {
+        .instance_size = sizeof(ExternalSnapshotState),
+        .prepare  = external_snapshot_prepare,
+        .commit   = external_snapshot_commit,
+        .abort = external_snapshot_abort,
+        .clean = external_snapshot_clean,
+    },
+    [TRANSACTION_ACTION_KIND_DRIVE_BACKUP] = {
+        .instance_size = sizeof(DriveBackupState),
+        .prepare = drive_backup_prepare,
+        .commit = drive_backup_commit,
+        .abort = drive_backup_abort,
+        .clean = drive_backup_clean,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP] = {
+        .instance_size = sizeof(BlockdevBackupState),
+        .prepare = blockdev_backup_prepare,
+        .commit = blockdev_backup_commit,
+        .abort = blockdev_backup_abort,
+        .clean = blockdev_backup_clean,
+    },
+    [TRANSACTION_ACTION_KIND_ABORT] = {
+        .instance_size = sizeof(BlkActionState),
+        .prepare = abort_prepare,
+        .commit = abort_commit,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCKDEV_SNAPSHOT_INTERNAL_SYNC] = {
+        .instance_size = sizeof(InternalSnapshotState),
+        .prepare  = internal_snapshot_prepare,
+        .abort = internal_snapshot_abort,
+        .clean = internal_snapshot_clean,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ADD] = {
+        .instance_size = sizeof(BlockDirtyBitmapState),
+        .prepare = block_dirty_bitmap_add_prepare,
+        .abort = block_dirty_bitmap_add_abort,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_CLEAR] = {
+        .instance_size = sizeof(BlockDirtyBitmapState),
+        .prepare = block_dirty_bitmap_clear_prepare,
+        .commit = block_dirty_bitmap_free_backup,
+        .abort = block_dirty_bitmap_restore,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_ENABLE] = {
+        .instance_size = sizeof(BlockDirtyBitmapState),
+        .prepare = block_dirty_bitmap_enable_prepare,
+        .abort = block_dirty_bitmap_enable_abort,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_DISABLE] = {
+        .instance_size = sizeof(BlockDirtyBitmapState),
+        .prepare = block_dirty_bitmap_disable_prepare,
+        .abort = block_dirty_bitmap_disable_abort,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_MERGE] = {
+        .instance_size = sizeof(BlockDirtyBitmapState),
+        .prepare = block_dirty_bitmap_merge_prepare,
+        .commit = block_dirty_bitmap_free_backup,
+        .abort = block_dirty_bitmap_restore,
+    },
+    [TRANSACTION_ACTION_KIND_BLOCK_DIRTY_BITMAP_REMOVE] = {
+        .instance_size = sizeof(BlockDirtyBitmapState),
+        .prepare = block_dirty_bitmap_remove_prepare,
+        .commit = block_dirty_bitmap_remove_commit,
+        .abort = block_dirty_bitmap_remove_abort,
+    },
+    /* Where are transactions for MIRROR, COMMIT and STREAM?
+     * Although these blockjobs use transaction callbacks like the backup job,
+     * these jobs do not necessarily adhere to transaction semantics.
+     * These jobs may not fully undo all of their actions on abort, nor do they
+     * necessarily work in transactions with more than one job in them.
+     */
+};
+
+/**
+ * Allocate a TransactionProperties structure if necessary, and fill
+ * that structure with desired defaults if they are unset.
+ */
+static TransactionProperties *get_transaction_properties(
+    TransactionProperties *props)
+{
+    if (!props) {
+        props = g_new0(TransactionProperties, 1);
+    }
+
+    if (!props->has_completion_mode) {
+        props->has_completion_mode = true;
+        props->completion_mode = ACTION_COMPLETION_MODE_INDIVIDUAL;
+    }
+
+    return props;
+}
+
+/*
+ * 'Atomic' group operations.  The operations are performed as a set, and if
+ * any fail then we roll back all operations in the group.
+ */
+void qmp_transaction(TransactionActionList *dev_list,
+                     bool has_props,
+                     struct TransactionProperties *props,
+                     Error **errp)
+{
+    TransactionActionList *dev_entry = dev_list;
+    JobTxn *block_job_txn = NULL;
+    BlkActionState *state, *next;
+    Error *local_err = NULL;
+
+    QTAILQ_HEAD(, BlkActionState) snap_bdrv_states;
+    QTAILQ_INIT(&snap_bdrv_states);
+
+    /* Does this transaction get canceled as a group on failure?
+     * If not, we don't really need to make a JobTxn.
+     */
+    props = get_transaction_properties(props);
+    if (props->completion_mode != ACTION_COMPLETION_MODE_INDIVIDUAL) {
+        block_job_txn = job_txn_new();
+    }
+
+    /* drain all i/o before any operations */
+    bdrv_drain_all();
+
+    /* We don't do anything in this loop that commits us to the operations */
+    while (NULL != dev_entry) {
+        TransactionAction *dev_info = NULL;
+        const BlkActionOps *ops;
+
+        dev_info = dev_entry->value;
+        dev_entry = dev_entry->next;
+
+        assert(dev_info->type < ARRAY_SIZE(actions));
+
+        ops = &actions[dev_info->type];
+        assert(ops->instance_size > 0);
+
+        state = g_malloc0(ops->instance_size);
+        state->ops = ops;
+        state->action = dev_info;
+        state->block_job_txn = block_job_txn;
+        state->txn_props = props;
+        QTAILQ_INSERT_TAIL(&snap_bdrv_states, state, entry);
+
+        state->ops->prepare(state, &local_err);
+        if (local_err) {
+            error_propagate(errp, local_err);
+            goto delete_and_fail;
+        }
+    }
+
+    QTAILQ_FOREACH(state, &snap_bdrv_states, entry) {
+        if (state->ops->commit) {
+            state->ops->commit(state);
+        }
+    }
+
+    /* success */
+    goto exit;
+
+delete_and_fail:
+    /* failure, and it is all-or-none; roll back all operations */
+    QTAILQ_FOREACH_REVERSE(state, &snap_bdrv_states, entry) {
+        if (state->ops->abort) {
+            state->ops->abort(state);
+        }
+    }
+exit:
+    QTAILQ_FOREACH_SAFE(state, &snap_bdrv_states, entry, next) {
+        if (state->ops->clean) {
+            state->ops->clean(state);
+        }
+        g_free(state);
+    }
+    if (!has_props) {
+        qapi_free_TransactionProperties(props);
+    }
+    job_txn_unref(block_job_txn);
+}
+
+BlockDirtyBitmapSha256 *qmp_x_debug_block_dirty_bitmap_sha256(const char *node,
+                                                              const char *name,
+                                                              Error **errp)
+{
+    BdrvDirtyBitmap *bitmap;
+    BlockDriverState *bs;
+    BlockDirtyBitmapSha256 *ret = NULL;
+    char *sha256;
+
+    bitmap = block_dirty_bitmap_lookup(node, name, &bs, errp);
+    if (!bitmap || !bs) {
+        return NULL;
+    }
+
+    sha256 = bdrv_dirty_bitmap_sha256(bitmap, errp);
+    if (sha256 == NULL) {
+        return NULL;
+    }
+
+    ret = g_new(BlockDirtyBitmapSha256, 1);
+    ret->sha256 = sha256;
+
+    return ret;
+}
+
+void coroutine_fn qmp_block_resize(bool has_device, const char *device,
+                                   bool has_node_name, const char *node_name,
+                                   int64_t size, Error **errp)
+{
+    Error *local_err = NULL;
+    BlockBackend *blk;
+    BlockDriverState *bs;
+    AioContext *old_ctx;
+
+    bs = bdrv_lookup_bs(has_device ? device : NULL,
+                        has_node_name ? node_name : NULL,
+                        &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
+
+    if (size < 0) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "size", "a >0 size");
+        return;
+    }
+
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, NULL)) {
+        error_setg(errp, QERR_DEVICE_IN_USE, device);
+        return;
+    }
+
+    blk = blk_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, errp);
+    if (!blk) {
+        return;
+    }
+
+    bdrv_co_lock(bs);
+    bdrv_drained_begin(bs);
+    bdrv_co_unlock(bs);
+
+    old_ctx = bdrv_co_enter(bs);
+    blk_truncate(blk, size, false, PREALLOC_MODE_OFF, 0, errp);
+    bdrv_co_leave(bs, old_ctx);
+
+    bdrv_co_lock(bs);
+    bdrv_drained_end(bs);
+    blk_unref(blk);
+    bdrv_co_unlock(bs);
+}
+
+void qmp_block_stream(bool has_job_id, const char *job_id, const char *device,
+                      bool has_base, const char *base,
+                      bool has_base_node, const char *base_node,
+                      bool has_backing_file, const char *backing_file,
+                      bool has_bottom, const char *bottom,
+                      bool has_speed, int64_t speed,
+                      bool has_on_error, BlockdevOnError on_error,
+                      bool has_filter_node_name, const char *filter_node_name,
+                      bool has_auto_finalize, bool auto_finalize,
+                      bool has_auto_dismiss, bool auto_dismiss,
+                      Error **errp)
+{
+    BlockDriverState *bs, *iter, *iter_end;
+    BlockDriverState *base_bs = NULL;
+    BlockDriverState *bottom_bs = NULL;
+    AioContext *aio_context;
+    Error *local_err = NULL;
+    int job_flags = JOB_DEFAULT;
+
+    if (has_base && has_base_node) {
+        error_setg(errp, "'base' and 'base-node' cannot be specified "
+                   "at the same time");
+        return;
+    }
+
+    if (has_base && has_bottom) {
+        error_setg(errp, "'base' and 'bottom' cannot be specified "
+                   "at the same time");
+        return;
+    }
+
+    if (has_bottom && has_base_node) {
+        error_setg(errp, "'bottom' and 'base-node' cannot be specified "
+                   "at the same time");
+        return;
+    }
+
+    if (!has_on_error) {
+        on_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+
+    bs = bdrv_lookup_bs(device, device, errp);
+    if (!bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    if (has_base) {
+        base_bs = bdrv_find_backing_image(bs, base);
+        if (base_bs == NULL) {
+            error_setg(errp, "Can't find '%s' in the backing chain", base);
+            goto out;
+        }
+        assert(bdrv_get_aio_context(base_bs) == aio_context);
+    }
+
+    if (has_base_node) {
+        base_bs = bdrv_lookup_bs(NULL, base_node, errp);
+        if (!base_bs) {
+            goto out;
+        }
+        if (bs == base_bs || !bdrv_chain_contains(bs, base_bs)) {
+            error_setg(errp, "Node '%s' is not a backing image of '%s'",
+                       base_node, device);
+            goto out;
+        }
+        assert(bdrv_get_aio_context(base_bs) == aio_context);
+        bdrv_refresh_filename(base_bs);
+    }
+
+    if (has_bottom) {
+        bottom_bs = bdrv_lookup_bs(NULL, bottom, errp);
+        if (!bottom_bs) {
+            goto out;
+        }
+        if (!bottom_bs->drv) {
+            error_setg(errp, "Node '%s' is not open", bottom);
+            goto out;
+        }
+        if (bottom_bs->drv->is_filter) {
+            error_setg(errp, "Node '%s' is a filter, use a non-filter node "
+                       "as 'bottom'", bottom);
+            goto out;
+        }
+        if (!bdrv_chain_contains(bs, bottom_bs)) {
+            error_setg(errp, "Node '%s' is not in a chain starting from '%s'",
+                       bottom, device);
+            goto out;
+        }
+        assert(bdrv_get_aio_context(bottom_bs) == aio_context);
+    }
+
+    /*
+     * Check for op blockers in the whole chain between bs and base (or bottom)
+     */
+    iter_end = has_bottom ? bdrv_filter_or_cow_bs(bottom_bs) : base_bs;
+    for (iter = bs; iter && iter != iter_end;
+         iter = bdrv_filter_or_cow_bs(iter))
+    {
+        if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
+            goto out;
+        }
+    }
+
+    /* if we are streaming the entire chain, the result will have no backing
+     * file, and specifying one is therefore an error */
+    if (base_bs == NULL && has_backing_file) {
+        error_setg(errp, "backing file specified, but streaming the "
+                         "entire chain");
+        goto out;
+    }
+
+    if (has_auto_finalize && !auto_finalize) {
+        job_flags |= JOB_MANUAL_FINALIZE;
+    }
+    if (has_auto_dismiss && !auto_dismiss) {
+        job_flags |= JOB_MANUAL_DISMISS;
+    }
+
+    stream_start(has_job_id ? job_id : NULL, bs, base_bs, backing_file,
+                 bottom_bs, job_flags, has_speed ? speed : 0, on_error,
+                 filter_node_name, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    trace_qmp_block_stream(bs);
+
+out:
+    aio_context_release(aio_context);
+}
+
+void qmp_block_commit(bool has_job_id, const char *job_id, const char *device,
+                      bool has_base_node, const char *base_node,
+                      bool has_base, const char *base,
+                      bool has_top_node, const char *top_node,
+                      bool has_top, const char *top,
+                      bool has_backing_file, const char *backing_file,
+                      bool has_speed, int64_t speed,
+                      bool has_on_error, BlockdevOnError on_error,
+                      bool has_filter_node_name, const char *filter_node_name,
+                      bool has_auto_finalize, bool auto_finalize,
+                      bool has_auto_dismiss, bool auto_dismiss,
+                      Error **errp)
+{
+    BlockDriverState *bs;
+    BlockDriverState *iter;
+    BlockDriverState *base_bs, *top_bs;
+    AioContext *aio_context;
+    Error *local_err = NULL;
+    int job_flags = JOB_DEFAULT;
+    uint64_t top_perm, top_shared;
+
+    if (!has_speed) {
+        speed = 0;
+    }
+    if (!has_on_error) {
+        on_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+    if (!has_filter_node_name) {
+        filter_node_name = NULL;
+    }
+    if (has_auto_finalize && !auto_finalize) {
+        job_flags |= JOB_MANUAL_FINALIZE;
+    }
+    if (has_auto_dismiss && !auto_dismiss) {
+        job_flags |= JOB_MANUAL_DISMISS;
+    }
+
+    /* Important Note:
+     *  libvirt relies on the DeviceNotFound error class in order to probe for
+     *  live commit feature versions; for this to work, we must make sure to
+     *  perform the device lookup before any generic errors that may occur in a
+     *  scenario in which all optional arguments are omitted. */
+    bs = qmp_get_root_bs(device, &local_err);
+    if (!bs) {
+        bs = bdrv_lookup_bs(device, device, NULL);
+        if (!bs) {
+            error_free(local_err);
+            error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
+                      "Device '%s' not found", device);
+        } else {
+            error_propagate(errp, local_err);
+        }
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_COMMIT_SOURCE, errp)) {
+        goto out;
+    }
+
+    /* default top_bs is the active layer */
+    top_bs = bs;
+
+    if (has_top_node && has_top) {
+        error_setg(errp, "'top-node' and 'top' are mutually exclusive");
+        goto out;
+    } else if (has_top_node) {
+        top_bs = bdrv_lookup_bs(NULL, top_node, errp);
+        if (top_bs == NULL) {
+            goto out;
+        }
+        if (!bdrv_chain_contains(bs, top_bs)) {
+            error_setg(errp, "'%s' is not in this backing file chain",
+                       top_node);
+            goto out;
+        }
+    } else if (has_top && top) {
+        /* This strcmp() is just a shortcut, there is no need to
+         * refresh @bs's filename.  If it mismatches,
+         * bdrv_find_backing_image() will do the refresh and may still
+         * return @bs. */
+        if (strcmp(bs->filename, top) != 0) {
+            top_bs = bdrv_find_backing_image(bs, top);
+        }
+    }
+
+    if (top_bs == NULL) {
+        error_setg(errp, "Top image file %s not found", top ? top : "NULL");
+        goto out;
+    }
+
+    assert(bdrv_get_aio_context(top_bs) == aio_context);
+
+    if (has_base_node && has_base) {
+        error_setg(errp, "'base-node' and 'base' are mutually exclusive");
+        goto out;
+    } else if (has_base_node) {
+        base_bs = bdrv_lookup_bs(NULL, base_node, errp);
+        if (base_bs == NULL) {
+            goto out;
+        }
+        if (!bdrv_chain_contains(top_bs, base_bs)) {
+            error_setg(errp, "'%s' is not in this backing file chain",
+                       base_node);
+            goto out;
+        }
+    } else if (has_base && base) {
+        base_bs = bdrv_find_backing_image(top_bs, base);
+        if (base_bs == NULL) {
+            error_setg(errp, "Can't find '%s' in the backing chain", base);
+            goto out;
+        }
+    } else {
+        base_bs = bdrv_find_base(top_bs);
+        if (base_bs == NULL) {
+            error_setg(errp, "There is no backimg image");
+            goto out;
+        }
+    }
+
+    assert(bdrv_get_aio_context(base_bs) == aio_context);
+
+    for (iter = top_bs; iter != bdrv_filter_or_cow_bs(base_bs);
+         iter = bdrv_filter_or_cow_bs(iter))
+    {
+        if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
+            goto out;
+        }
+    }
+
+    /* Do not allow attempts to commit an image into itself */
+    if (top_bs == base_bs) {
+        error_setg(errp, "cannot commit an image into itself");
+        goto out;
+    }
+
+    /*
+     * Active commit is required if and only if someone has taken a
+     * WRITE permission on the top node.  Historically, we have always
+     * used active commit for top nodes, so continue that practice
+     * lest we possibly break clients that rely on this behavior, e.g.
+     * to later attach this node to a writing parent.
+     * (Active commit is never really wrong.)
+     */
+    bdrv_get_cumulative_perm(top_bs, &top_perm, &top_shared);
+    if (top_perm & BLK_PERM_WRITE ||
+        bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs))
+    {
+        if (has_backing_file) {
+            if (bdrv_skip_filters(top_bs) == bdrv_skip_filters(bs)) {
+                error_setg(errp, "'backing-file' specified,"
+                                 " but 'top' is the active layer");
+            } else {
+                error_setg(errp, "'backing-file' specified, but 'top' has a "
+                                 "writer on it");
+            }
+            goto out;
+        }
+        if (!has_job_id) {
+            /*
+             * Emulate here what block_job_create() does, because it
+             * is possible that @bs != @top_bs (the block job should
+             * be named after @bs, even if @top_bs is the actual
+             * source)
+             */
+            job_id = bdrv_get_device_name(bs);
+        }
+        commit_active_start(job_id, top_bs, base_bs, job_flags, speed, on_error,
+                            filter_node_name, NULL, NULL, false, &local_err);
+    } else {
+        BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs);
+        if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) {
+            goto out;
+        }
+        commit_start(has_job_id ? job_id : NULL, bs, base_bs, top_bs, job_flags,
+                     speed, on_error, has_backing_file ? backing_file : NULL,
+                     filter_node_name, &local_err);
+    }
+    if (local_err != NULL) {
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+out:
+    aio_context_release(aio_context);
+}
+
+/* Common QMP interface for drive-backup and blockdev-backup */
+static BlockJob *do_backup_common(BackupCommon *backup,
+                                  BlockDriverState *bs,
+                                  BlockDriverState *target_bs,
+                                  AioContext *aio_context,
+                                  JobTxn *txn, Error **errp)
+{
+    BlockJob *job = NULL;
+    BdrvDirtyBitmap *bmap = NULL;
+    BackupPerf perf = { .max_workers = 64 };
+    int job_flags = JOB_DEFAULT;
+
+    if (!backup->has_speed) {
+        backup->speed = 0;
+    }
+    if (!backup->has_on_source_error) {
+        backup->on_source_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+    if (!backup->has_on_target_error) {
+        backup->on_target_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+    if (!backup->has_job_id) {
+        backup->job_id = NULL;
+    }
+    if (!backup->has_auto_finalize) {
+        backup->auto_finalize = true;
+    }
+    if (!backup->has_auto_dismiss) {
+        backup->auto_dismiss = true;
+    }
+    if (!backup->has_compress) {
+        backup->compress = false;
+    }
+
+    if (backup->x_perf) {
+        if (backup->x_perf->has_use_copy_range) {
+            perf.use_copy_range = backup->x_perf->use_copy_range;
+        }
+        if (backup->x_perf->has_max_workers) {
+            perf.max_workers = backup->x_perf->max_workers;
+        }
+        if (backup->x_perf->has_max_chunk) {
+            perf.max_chunk = backup->x_perf->max_chunk;
+        }
+    }
+
+    if ((backup->sync == MIRROR_SYNC_MODE_BITMAP) ||
+        (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL)) {
+        /* done before desugaring 'incremental' to print the right message */
+        if (!backup->has_bitmap) {
+            error_setg(errp, "must provide a valid bitmap name for "
+                       "'%s' sync mode", MirrorSyncMode_str(backup->sync));
+            return NULL;
+        }
+    }
+
+    if (backup->sync == MIRROR_SYNC_MODE_INCREMENTAL) {
+        if (backup->has_bitmap_mode &&
+            backup->bitmap_mode != BITMAP_SYNC_MODE_ON_SUCCESS) {
+            error_setg(errp, "Bitmap sync mode must be '%s' "
+                       "when using sync mode '%s'",
+                       BitmapSyncMode_str(BITMAP_SYNC_MODE_ON_SUCCESS),
+                       MirrorSyncMode_str(backup->sync));
+            return NULL;
+        }
+        backup->has_bitmap_mode = true;
+        backup->sync = MIRROR_SYNC_MODE_BITMAP;
+        backup->bitmap_mode = BITMAP_SYNC_MODE_ON_SUCCESS;
+    }
+
+    if (backup->has_bitmap) {
+        bmap = bdrv_find_dirty_bitmap(bs, backup->bitmap);
+        if (!bmap) {
+            error_setg(errp, "Bitmap '%s' could not be found", backup->bitmap);
+            return NULL;
+        }
+        if (!backup->has_bitmap_mode) {
+            error_setg(errp, "Bitmap sync mode must be given "
+                       "when providing a bitmap");
+            return NULL;
+        }
+        if (bdrv_dirty_bitmap_check(bmap, BDRV_BITMAP_ALLOW_RO, errp)) {
+            return NULL;
+        }
+
+        /* This does not produce a useful bitmap artifact: */
+        if (backup->sync == MIRROR_SYNC_MODE_NONE) {
+            error_setg(errp, "sync mode '%s' does not produce meaningful bitmap"
+                       " outputs", MirrorSyncMode_str(backup->sync));
+            return NULL;
+        }
+
+        /* If the bitmap isn't used for input or output, this is useless: */
+        if (backup->bitmap_mode == BITMAP_SYNC_MODE_NEVER &&
+            backup->sync != MIRROR_SYNC_MODE_BITMAP) {
+            error_setg(errp, "Bitmap sync mode '%s' has no meaningful effect"
+                       " when combined with sync mode '%s'",
+                       BitmapSyncMode_str(backup->bitmap_mode),
+                       MirrorSyncMode_str(backup->sync));
+            return NULL;
+        }
+    }
+
+    if (!backup->has_bitmap && backup->has_bitmap_mode) {
+        error_setg(errp, "Cannot specify bitmap sync mode without a bitmap");
+        return NULL;
+    }
+
+    if (!backup->auto_finalize) {
+        job_flags |= JOB_MANUAL_FINALIZE;
+    }
+    if (!backup->auto_dismiss) {
+        job_flags |= JOB_MANUAL_DISMISS;
+    }
+
+    job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
+                            backup->sync, bmap, backup->bitmap_mode,
+                            backup->compress,
+                            backup->filter_node_name,
+                            &perf,
+                            backup->on_source_error,
+                            backup->on_target_error,
+                            job_flags, NULL, NULL, txn, errp);
+    return job;
+}
+
+void qmp_drive_backup(DriveBackup *backup, Error **errp)
+{
+    TransactionAction action = {
+        .type = TRANSACTION_ACTION_KIND_DRIVE_BACKUP,
+        .u.drive_backup.data = backup,
+    };
+    blockdev_do_action(&action, errp);
+}
+
+BlockDeviceInfoList *qmp_query_named_block_nodes(bool has_flat,
+                                                 bool flat,
+                                                 Error **errp)
+{
+    bool return_flat = has_flat && flat;
+
+    return bdrv_named_nodes_list(return_flat, errp);
+}
+
+XDbgBlockGraph *qmp_x_debug_query_block_graph(Error **errp)
+{
+    return bdrv_get_xdbg_block_graph(errp);
+}
+
+void qmp_blockdev_backup(BlockdevBackup *backup, Error **errp)
+{
+    TransactionAction action = {
+        .type = TRANSACTION_ACTION_KIND_BLOCKDEV_BACKUP,
+        .u.blockdev_backup.data = backup,
+    };
+    blockdev_do_action(&action, errp);
+}
+
+/* Parameter check and block job starting for drive mirroring.
+ * Caller should hold @device and @target's aio context (must be the same).
+ **/
+static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs,
+                                   BlockDriverState *target,
+                                   bool has_replaces, const char *replaces,
+                                   enum MirrorSyncMode sync,
+                                   BlockMirrorBackingMode backing_mode,
+                                   bool zero_target,
+                                   bool has_speed, int64_t speed,
+                                   bool has_granularity, uint32_t granularity,
+                                   bool has_buf_size, int64_t buf_size,
+                                   bool has_on_source_error,
+                                   BlockdevOnError on_source_error,
+                                   bool has_on_target_error,
+                                   BlockdevOnError on_target_error,
+                                   bool has_unmap, bool unmap,
+                                   bool has_filter_node_name,
+                                   const char *filter_node_name,
+                                   bool has_copy_mode, MirrorCopyMode copy_mode,
+                                   bool has_auto_finalize, bool auto_finalize,
+                                   bool has_auto_dismiss, bool auto_dismiss,
+                                   Error **errp)
+{
+    BlockDriverState *unfiltered_bs;
+    int job_flags = JOB_DEFAULT;
+
+    if (!has_speed) {
+        speed = 0;
+    }
+    if (!has_on_source_error) {
+        on_source_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+    if (!has_on_target_error) {
+        on_target_error = BLOCKDEV_ON_ERROR_REPORT;
+    }
+    if (!has_granularity) {
+        granularity = 0;
+    }
+    if (!has_buf_size) {
+        buf_size = 0;
+    }
+    if (!has_unmap) {
+        unmap = true;
+    }
+    if (!has_filter_node_name) {
+        filter_node_name = NULL;
+    }
+    if (!has_copy_mode) {
+        copy_mode = MIRROR_COPY_MODE_BACKGROUND;
+    }
+    if (has_auto_finalize && !auto_finalize) {
+        job_flags |= JOB_MANUAL_FINALIZE;
+    }
+    if (has_auto_dismiss && !auto_dismiss) {
+        job_flags |= JOB_MANUAL_DISMISS;
+    }
+
+    if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
+                   "a value in range [512B, 64MB]");
+        return;
+    }
+    if (granularity & (granularity - 1)) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity",
+                   "a power of 2");
+        return;
+    }
+
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
+        return;
+    }
+    if (bdrv_op_is_blocked(target, BLOCK_OP_TYPE_MIRROR_TARGET, errp)) {
+        return;
+    }
+
+    if (!bdrv_backing_chain_next(bs) && sync == MIRROR_SYNC_MODE_TOP) {
+        sync = MIRROR_SYNC_MODE_FULL;
+    }
+
+    if (!has_replaces) {
+        /* We want to mirror from @bs, but keep implicit filters on top */
+        unfiltered_bs = bdrv_skip_implicit_filters(bs);
+        if (unfiltered_bs != bs) {
+            replaces = unfiltered_bs->node_name;
+            has_replaces = true;
+        }
+    }
+
+    if (has_replaces) {
+        BlockDriverState *to_replace_bs;
+        AioContext *replace_aio_context;
+        int64_t bs_size, replace_size;
+
+        bs_size = bdrv_getlength(bs);
+        if (bs_size < 0) {
+            error_setg_errno(errp, -bs_size, "Failed to query device's size");
+            return;
+        }
+
+        to_replace_bs = check_to_replace_node(bs, replaces, errp);
+        if (!to_replace_bs) {
+            return;
+        }
+
+        replace_aio_context = bdrv_get_aio_context(to_replace_bs);
+        aio_context_acquire(replace_aio_context);
+        replace_size = bdrv_getlength(to_replace_bs);
+        aio_context_release(replace_aio_context);
+
+        if (replace_size < 0) {
+            error_setg_errno(errp, -replace_size,
+                             "Failed to query the replacement node's size");
+            return;
+        }
+        if (bs_size != replace_size) {
+            error_setg(errp, "cannot replace image with a mirror image of "
+                             "different size");
+            return;
+        }
+    }
+
+    /* pass the node name to replace to mirror start since it's loose coupling
+     * and will allow to check whether the node still exist at mirror completion
+     */
+    mirror_start(job_id, bs, target,
+                 has_replaces ? replaces : NULL, job_flags,
+                 speed, granularity, buf_size, sync, backing_mode, zero_target,
+                 on_source_error, on_target_error, unmap, filter_node_name,
+                 copy_mode, errp);
+}
+
+void qmp_drive_mirror(DriveMirror *arg, Error **errp)
+{
+    BlockDriverState *bs;
+    BlockDriverState *target_backing_bs, *target_bs;
+    AioContext *aio_context;
+    AioContext *old_context;
+    BlockMirrorBackingMode backing_mode;
+    Error *local_err = NULL;
+    QDict *options = NULL;
+    int flags;
+    int64_t size;
+    const char *format = arg->format;
+    bool zero_target;
+    int ret;
+
+    bs = qmp_get_root_bs(arg->device, errp);
+    if (!bs) {
+        return;
+    }
+
+    /* Early check to avoid creating target */
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    if (!arg->has_mode) {
+        arg->mode = NEW_IMAGE_MODE_ABSOLUTE_PATHS;
+    }
+
+    if (!arg->has_format) {
+        format = (arg->mode == NEW_IMAGE_MODE_EXISTING
+                  ? NULL : bs->drv->format_name);
+    }
+
+    flags = bs->open_flags | BDRV_O_RDWR;
+    target_backing_bs = bdrv_cow_bs(bdrv_skip_filters(bs));
+    if (!target_backing_bs && arg->sync == MIRROR_SYNC_MODE_TOP) {
+        arg->sync = MIRROR_SYNC_MODE_FULL;
+    }
+    if (arg->sync == MIRROR_SYNC_MODE_NONE) {
+        target_backing_bs = bs;
+    }
+
+    size = bdrv_getlength(bs);
+    if (size < 0) {
+        error_setg_errno(errp, -size, "bdrv_getlength failed");
+        goto out;
+    }
+
+    if (arg->has_replaces) {
+        if (!arg->has_node_name) {
+            error_setg(errp, "a node-name must be provided when replacing a"
+                             " named node of the graph");
+            goto out;
+        }
+    }
+
+    if (arg->mode == NEW_IMAGE_MODE_ABSOLUTE_PATHS) {
+        backing_mode = MIRROR_SOURCE_BACKING_CHAIN;
+    } else {
+        backing_mode = MIRROR_OPEN_BACKING_CHAIN;
+    }
+
+    /* Don't open backing image in create() */
+    flags |= BDRV_O_NO_BACKING;
+
+    if ((arg->sync == MIRROR_SYNC_MODE_FULL || !target_backing_bs)
+        && arg->mode != NEW_IMAGE_MODE_EXISTING)
+    {
+        /* create new image w/o backing file */
+        assert(format);
+        bdrv_img_create(arg->target, format,
+                        NULL, NULL, NULL, size, flags, false, &local_err);
+    } else {
+        /* Implicit filters should not appear in the filename */
+        BlockDriverState *explicit_backing =
+            bdrv_skip_implicit_filters(target_backing_bs);
+
+        switch (arg->mode) {
+        case NEW_IMAGE_MODE_EXISTING:
+            break;
+        case NEW_IMAGE_MODE_ABSOLUTE_PATHS:
+            /* create new image with backing file */
+            bdrv_refresh_filename(explicit_backing);
+            bdrv_img_create(arg->target, format,
+                            explicit_backing->filename,
+                            explicit_backing->drv->format_name,
+                            NULL, size, flags, false, &local_err);
+            break;
+        default:
+            abort();
+        }
+    }
+
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    options = qdict_new();
+    if (arg->has_node_name) {
+        qdict_put_str(options, "node-name", arg->node_name);
+    }
+    if (format) {
+        qdict_put_str(options, "driver", format);
+    }
+
+    /* Mirroring takes care of copy-on-write using the source's backing
+     * file.
+     */
+    target_bs = bdrv_open(arg->target, NULL, options, flags, errp);
+    if (!target_bs) {
+        goto out;
+    }
+
+    zero_target = (arg->sync == MIRROR_SYNC_MODE_FULL &&
+                   (arg->mode == NEW_IMAGE_MODE_EXISTING ||
+                    !bdrv_has_zero_init(target_bs)));
+
+
+    /* Honor bdrv_try_set_aio_context() context acquisition requirements. */
+    old_context = bdrv_get_aio_context(target_bs);
+    aio_context_release(aio_context);
+    aio_context_acquire(old_context);
+
+    ret = bdrv_try_set_aio_context(target_bs, aio_context, errp);
+    if (ret < 0) {
+        bdrv_unref(target_bs);
+        aio_context_release(old_context);
+        return;
+    }
+
+    aio_context_release(old_context);
+    aio_context_acquire(aio_context);
+
+    blockdev_mirror_common(arg->has_job_id ? arg->job_id : NULL, bs, target_bs,
+                           arg->has_replaces, arg->replaces, arg->sync,
+                           backing_mode, zero_target,
+                           arg->has_speed, arg->speed,
+                           arg->has_granularity, arg->granularity,
+                           arg->has_buf_size, arg->buf_size,
+                           arg->has_on_source_error, arg->on_source_error,
+                           arg->has_on_target_error, arg->on_target_error,
+                           arg->has_unmap, arg->unmap,
+                           false, NULL,
+                           arg->has_copy_mode, arg->copy_mode,
+                           arg->has_auto_finalize, arg->auto_finalize,
+                           arg->has_auto_dismiss, arg->auto_dismiss,
+                           errp);
+    bdrv_unref(target_bs);
+out:
+    aio_context_release(aio_context);
+}
+
+void qmp_blockdev_mirror(bool has_job_id, const char *job_id,
+                         const char *device, const char *target,
+                         bool has_replaces, const char *replaces,
+                         MirrorSyncMode sync,
+                         bool has_speed, int64_t speed,
+                         bool has_granularity, uint32_t granularity,
+                         bool has_buf_size, int64_t buf_size,
+                         bool has_on_source_error,
+                         BlockdevOnError on_source_error,
+                         bool has_on_target_error,
+                         BlockdevOnError on_target_error,
+                         bool has_filter_node_name,
+                         const char *filter_node_name,
+                         bool has_copy_mode, MirrorCopyMode copy_mode,
+                         bool has_auto_finalize, bool auto_finalize,
+                         bool has_auto_dismiss, bool auto_dismiss,
+                         Error **errp)
+{
+    BlockDriverState *bs;
+    BlockDriverState *target_bs;
+    AioContext *aio_context;
+    AioContext *old_context;
+    BlockMirrorBackingMode backing_mode = MIRROR_LEAVE_BACKING_CHAIN;
+    bool zero_target;
+    int ret;
+
+    bs = qmp_get_root_bs(device, errp);
+    if (!bs) {
+        return;
+    }
+
+    target_bs = bdrv_lookup_bs(target, target, errp);
+    if (!target_bs) {
+        return;
+    }
+
+    zero_target = (sync == MIRROR_SYNC_MODE_FULL);
+
+    /* Honor bdrv_try_set_aio_context() context acquisition requirements. */
+    old_context = bdrv_get_aio_context(target_bs);
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(old_context);
+
+    ret = bdrv_try_set_aio_context(target_bs, aio_context, errp);
+
+    aio_context_release(old_context);
+    aio_context_acquire(aio_context);
+
+    if (ret < 0) {
+        goto out;
+    }
+
+    blockdev_mirror_common(has_job_id ? job_id : NULL, bs, target_bs,
+                           has_replaces, replaces, sync, backing_mode,
+                           zero_target, has_speed, speed,
+                           has_granularity, granularity,
+                           has_buf_size, buf_size,
+                           has_on_source_error, on_source_error,
+                           has_on_target_error, on_target_error,
+                           true, true,
+                           has_filter_node_name, filter_node_name,
+                           has_copy_mode, copy_mode,
+                           has_auto_finalize, auto_finalize,
+                           has_auto_dismiss, auto_dismiss,
+                           errp);
+out:
+    aio_context_release(aio_context);
+}
+
+/* Get a block job using its ID and acquire its AioContext */
+static BlockJob *find_block_job(const char *id, AioContext **aio_context,
+                                Error **errp)
+{
+    BlockJob *job;
+
+    assert(id != NULL);
+
+    *aio_context = NULL;
+
+    job = block_job_get(id);
+
+    if (!job) {
+        error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
+                  "Block job '%s' not found", id);
+        return NULL;
+    }
+
+    *aio_context = blk_get_aio_context(job->blk);
+    aio_context_acquire(*aio_context);
+
+    return job;
+}
+
+void qmp_block_job_set_speed(const char *device, int64_t speed, Error **errp)
+{
+    AioContext *aio_context;
+    BlockJob *job = find_block_job(device, &aio_context, errp);
+
+    if (!job) {
+        return;
+    }
+
+    block_job_set_speed(job, speed, errp);
+    aio_context_release(aio_context);
+}
+
+void qmp_block_job_cancel(const char *device,
+                          bool has_force, bool force, Error **errp)
+{
+    AioContext *aio_context;
+    BlockJob *job = find_block_job(device, &aio_context, errp);
+
+    if (!job) {
+        return;
+    }
+
+    if (!has_force) {
+        force = false;
+    }
+
+    if (job_user_paused(&job->job) && !force) {
+        error_setg(errp, "The block job for device '%s' is currently paused",
+                   device);
+        goto out;
+    }
+
+    trace_qmp_block_job_cancel(job);
+    job_user_cancel(&job->job, force, errp);
+out:
+    aio_context_release(aio_context);
+}
+
+void qmp_block_job_pause(const char *device, Error **errp)
+{
+    AioContext *aio_context;
+    BlockJob *job = find_block_job(device, &aio_context, errp);
+
+    if (!job) {
+        return;
+    }
+
+    trace_qmp_block_job_pause(job);
+    job_user_pause(&job->job, errp);
+    aio_context_release(aio_context);
+}
+
+void qmp_block_job_resume(const char *device, Error **errp)
+{
+    AioContext *aio_context;
+    BlockJob *job = find_block_job(device, &aio_context, errp);
+
+    if (!job) {
+        return;
+    }
+
+    trace_qmp_block_job_resume(job);
+    job_user_resume(&job->job, errp);
+    aio_context_release(aio_context);
+}
+
+void qmp_block_job_complete(const char *device, Error **errp)
+{
+    AioContext *aio_context;
+    BlockJob *job = find_block_job(device, &aio_context, errp);
+
+    if (!job) {
+        return;
+    }
+
+    trace_qmp_block_job_complete(job);
+    job_complete(&job->job, errp);
+    aio_context_release(aio_context);
+}
+
+void qmp_block_job_finalize(const char *id, Error **errp)
+{
+    AioContext *aio_context;
+    BlockJob *job = find_block_job(id, &aio_context, errp);
+
+    if (!job) {
+        return;
+    }
+
+    trace_qmp_block_job_finalize(job);
+    job_ref(&job->job);
+    job_finalize(&job->job, errp);
+
+    /*
+     * Job's context might have changed via job_finalize (and job_txn_apply
+     * automatically acquires the new one), so make sure we release the correct
+     * one.
+     */
+    aio_context = blk_get_aio_context(job->blk);
+    job_unref(&job->job);
+    aio_context_release(aio_context);
+}
+
+void qmp_block_job_dismiss(const char *id, Error **errp)
+{
+    AioContext *aio_context;
+    BlockJob *bjob = find_block_job(id, &aio_context, errp);
+    Job *job;
+
+    if (!bjob) {
+        return;
+    }
+
+    trace_qmp_block_job_dismiss(bjob);
+    job = &bjob->job;
+    job_dismiss(&job, errp);
+    aio_context_release(aio_context);
+}
+
+void qmp_change_backing_file(const char *device,
+                             const char *image_node_name,
+                             const char *backing_file,
+                             Error **errp)
+{
+    BlockDriverState *bs = NULL;
+    AioContext *aio_context;
+    BlockDriverState *image_bs = NULL;
+    Error *local_err = NULL;
+    bool ro;
+    int ret;
+
+    bs = qmp_get_root_bs(device, errp);
+    if (!bs) {
+        return;
+    }
+
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    image_bs = bdrv_lookup_bs(NULL, image_node_name, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    if (!image_bs) {
+        error_setg(errp, "image file not found");
+        goto out;
+    }
+
+    if (bdrv_find_base(image_bs) == image_bs) {
+        error_setg(errp, "not allowing backing file change on an image "
+                         "without a backing file");
+        goto out;
+    }
+
+    /* even though we are not necessarily operating on bs, we need it to
+     * determine if block ops are currently prohibited on the chain */
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
+        goto out;
+    }
+
+    /* final sanity check */
+    if (!bdrv_chain_contains(bs, image_bs)) {
+        error_setg(errp, "'%s' and image file are not in the same chain",
+                   device);
+        goto out;
+    }
+
+    /* if not r/w, reopen to make r/w */
+    ro = bdrv_is_read_only(image_bs);
+
+    if (ro) {
+        if (bdrv_reopen_set_read_only(image_bs, false, errp) != 0) {
+            goto out;
+        }
+    }
+
+    ret = bdrv_change_backing_file(image_bs, backing_file,
+                                   image_bs->drv ? image_bs->drv->format_name : "",
+                                   false);
+
+    if (ret < 0) {
+        error_setg_errno(errp, -ret, "Could not change backing file to '%s'",
+                         backing_file);
+        /* don't exit here, so we can try to restore open flags if
+         * appropriate */
+    }
+
+    if (ro) {
+        bdrv_reopen_set_read_only(image_bs, true, errp);
+    }
+
+out:
+    aio_context_release(aio_context);
+}
+
+void qmp_blockdev_add(BlockdevOptions *options, Error **errp)
+{
+    BlockDriverState *bs;
+    QObject *obj;
+    Visitor *v = qobject_output_visitor_new(&obj);
+    QDict *qdict;
+
+    visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
+    visit_complete(v, &obj);
+    qdict = qobject_to(QDict, obj);
+
+    qdict_flatten(qdict);
+
+    if (!qdict_get_try_str(qdict, "node-name")) {
+        error_setg(errp, "'node-name' must be specified for the root node");
+        goto fail;
+    }
+
+    bs = bds_tree_init(qdict, errp);
+    if (!bs) {
+        goto fail;
+    }
+
+    bdrv_set_monitor_owned(bs);
+
+fail:
+    visit_free(v);
+}
+
+void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp)
+{
+    BlockReopenQueue *queue = NULL;
+    GSList *drained = NULL;
+
+    /* Add each one of the BDS that we want to reopen to the queue */
+    for (; reopen_list != NULL; reopen_list = reopen_list->next) {
+        BlockdevOptions *options = reopen_list->value;
+        BlockDriverState *bs;
+        AioContext *ctx;
+        QObject *obj;
+        Visitor *v;
+        QDict *qdict;
+
+        /* Check for the selected node name */
+        if (!options->has_node_name) {
+            error_setg(errp, "node-name not specified");
+            goto fail;
+        }
+
+        bs = bdrv_find_node(options->node_name);
+        if (!bs) {
+            error_setg(errp, "Failed to find node with node-name='%s'",
+                       options->node_name);
+            goto fail;
+        }
+
+        /* Put all options in a QDict and flatten it */
+        v = qobject_output_visitor_new(&obj);
+        visit_type_BlockdevOptions(v, NULL, &options, &error_abort);
+        visit_complete(v, &obj);
+        visit_free(v);
+
+        qdict = qobject_to(QDict, obj);
+
+        qdict_flatten(qdict);
+
+        ctx = bdrv_get_aio_context(bs);
+        aio_context_acquire(ctx);
+
+        bdrv_subtree_drained_begin(bs);
+        queue = bdrv_reopen_queue(queue, bs, qdict, false);
+        drained = g_slist_prepend(drained, bs);
+
+        aio_context_release(ctx);
+    }
+
+    /* Perform the reopen operation */
+    bdrv_reopen_multiple(queue, errp);
+    queue = NULL;
+
+fail:
+    bdrv_reopen_queue_free(queue);
+    g_slist_free_full(drained, (GDestroyNotify) bdrv_subtree_drained_end);
+}
+
+void qmp_blockdev_del(const char *node_name, Error **errp)
+{
+    AioContext *aio_context;
+    BlockDriverState *bs;
+
+    bs = bdrv_find_node(node_name);
+    if (!bs) {
+        error_setg(errp, "Failed to find node with node-name='%s'", node_name);
+        return;
+    }
+    if (bdrv_has_blk(bs)) {
+        error_setg(errp, "Node %s is in use", node_name);
+        return;
+    }
+    aio_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(aio_context);
+
+    if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_DRIVE_DEL, errp)) {
+        goto out;
+    }
+
+    if (!QTAILQ_IN_USE(bs, monitor_list)) {
+        error_setg(errp, "Node %s is not owned by the monitor",
+                   bs->node_name);
+        goto out;
+    }
+
+    if (bs->refcnt > 1) {
+        error_setg(errp, "Block device %s is in use",
+                   bdrv_get_device_or_node_name(bs));
+        goto out;
+    }
+
+    QTAILQ_REMOVE(&monitor_bdrv_states, bs, monitor_list);
+    bdrv_unref(bs);
+
+out:
+    aio_context_release(aio_context);
+}
+
+static BdrvChild *bdrv_find_child(BlockDriverState *parent_bs,
+                                  const char *child_name)
+{
+    BdrvChild *child;
+
+    QLIST_FOREACH(child, &parent_bs->children, next) {
+        if (strcmp(child->name, child_name) == 0) {
+            return child;
+        }
+    }
+
+    return NULL;
+}
+
+void qmp_x_blockdev_change(const char *parent, bool has_child,
+                           const char *child, bool has_node,
+                           const char *node, Error **errp)
+{
+    BlockDriverState *parent_bs, *new_bs = NULL;
+    BdrvChild *p_child;
+
+    parent_bs = bdrv_lookup_bs(parent, parent, errp);
+    if (!parent_bs) {
+        return;
+    }
+
+    if (has_child == has_node) {
+        if (has_child) {
+            error_setg(errp, "The parameters child and node are in conflict");
+        } else {
+            error_setg(errp, "Either child or node must be specified");
+        }
+        return;
+    }
+
+    if (has_child) {
+        p_child = bdrv_find_child(parent_bs, child);
+        if (!p_child) {
+            error_setg(errp, "Node '%s' does not have child '%s'",
+                       parent, child);
+            return;
+        }
+        bdrv_del_child(parent_bs, p_child, errp);
+    }
+
+    if (has_node) {
+        new_bs = bdrv_find_node(node);
+        if (!new_bs) {
+            error_setg(errp, "Node '%s' not found", node);
+            return;
+        }
+        bdrv_add_child(parent_bs, new_bs, errp);
+    }
+}
+
+BlockJobInfoList *qmp_query_block_jobs(Error **errp)
+{
+    BlockJobInfoList *head = NULL, **tail = &head;
+    BlockJob *job;
+
+    for (job = block_job_next(NULL); job; job = block_job_next(job)) {
+        BlockJobInfo *value;
+        AioContext *aio_context;
+
+        if (block_job_is_internal(job)) {
+            continue;
+        }
+        aio_context = blk_get_aio_context(job->blk);
+        aio_context_acquire(aio_context);
+        value = block_job_query(job, errp);
+        aio_context_release(aio_context);
+        if (!value) {
+            qapi_free_BlockJobInfoList(head);
+            return NULL;
+        }
+        QAPI_LIST_APPEND(tail, value);
+    }
+
+    return head;
+}
+
+void qmp_x_blockdev_set_iothread(const char *node_name, StrOrNull *iothread,
+                                 bool has_force, bool force, Error **errp)
+{
+    AioContext *old_context;
+    AioContext *new_context;
+    BlockDriverState *bs;
+
+    bs = bdrv_find_node(node_name);
+    if (!bs) {
+        error_setg(errp, "Failed to find node with node-name='%s'", node_name);
+        return;
+    }
+
+    /* Protects against accidents. */
+    if (!(has_force && force) && bdrv_has_blk(bs)) {
+        error_setg(errp, "Node %s is associated with a BlockBackend and could "
+                         "be in use (use force=true to override this check)",
+                         node_name);
+        return;
+    }
+
+    if (iothread->type == QTYPE_QSTRING) {
+        IOThread *obj = iothread_by_id(iothread->u.s);
+        if (!obj) {
+            error_setg(errp, "Cannot find iothread %s", iothread->u.s);
+            return;
+        }
+
+        new_context = iothread_get_aio_context(obj);
+    } else {
+        new_context = qemu_get_aio_context();
+    }
+
+    old_context = bdrv_get_aio_context(bs);
+    aio_context_acquire(old_context);
+
+    bdrv_try_set_aio_context(bs, new_context, errp);
+
+    aio_context_release(old_context);
+}
+
+QemuOptsList qemu_common_drive_opts = {
+    .name = "drive",
+    .head = QTAILQ_HEAD_INITIALIZER(qemu_common_drive_opts.head),
+    .desc = {
+        {
+            .name = "snapshot",
+            .type = QEMU_OPT_BOOL,
+            .help = "enable/disable snapshot mode",
+        },{
+            .name = "aio",
+            .type = QEMU_OPT_STRING,
+            .help = "host AIO implementation (threads, native, io_uring)",
+        },{
+            .name = BDRV_OPT_CACHE_WB,
+            .type = QEMU_OPT_BOOL,
+            .help = "Enable writeback mode",
+        },{
+            .name = "format",
+            .type = QEMU_OPT_STRING,
+            .help = "disk format (raw, qcow2, ...)",
+        },{
+            .name = "rerror",
+            .type = QEMU_OPT_STRING,
+            .help = "read error action",
+        },{
+            .name = "werror",
+            .type = QEMU_OPT_STRING,
+            .help = "write error action",
+        },{
+            .name = BDRV_OPT_READ_ONLY,
+            .type = QEMU_OPT_BOOL,
+            .help = "open drive file as read-only",
+        },
+
+        THROTTLE_OPTS,
+
+        {
+            .name = "throttling.group",
+            .type = QEMU_OPT_STRING,
+            .help = "name of the block throttling group",
+        },{
+            .name = "copy-on-read",
+            .type = QEMU_OPT_BOOL,
+            .help = "copy read data from backing file into image file",
+        },{
+            .name = "detect-zeroes",
+            .type = QEMU_OPT_STRING,
+            .help = "try to optimize zero writes (off, on, unmap)",
+        },{
+            .name = "stats-account-invalid",
+            .type = QEMU_OPT_BOOL,
+            .help = "whether to account for invalid I/O operations "
+                    "in the statistics",
+        },{
+            .name = "stats-account-failed",
+            .type = QEMU_OPT_BOOL,
+            .help = "whether to account for failed I/O operations "
+                    "in the statistics",
+        },
+        { /* end of list */ }
+    },
+};
+
+QemuOptsList qemu_drive_opts = {
+    .name = "drive",
+    .head = QTAILQ_HEAD_INITIALIZER(qemu_drive_opts.head),
+    .desc = {
+        /*
+         * no elements => accept any params
+         * validation will happen later
+         */
+        { /* end of list */ }
+    },
+};