[PATCH v15 0/5] backup-top filter driver for backup

[PATCH v15 0/5] backup-top filter driver for backup

[Vladimir Sementsov-Ogievskiy]

Hi all!

These series introduce backup-top driver. It's a filter-node, which
do copy-before-write operation. Mirror uses filter-node for handling
guest writes, let's move to filter-node (from write-notifiers) for
backup too.

Preparation patches are queued in Max's block branch:

Based-on: https://github.com/XanClic/qemu.git block

v15: use BdrvChildren in block-copy
01-03: new
04-05: a lot of changes, such as
04:
    - add new parameters for creation
    - prepare bcs creation
    - add target child
    - refactor bdrv_backup_top_append
    - drop r-b
05:
    - move block-copy to use BdrvChildren
    - drop extra style fixing hunks
    - iotest 141 output changed

v14: Drop range locks, keep old good in-flight requests waiting

12: new patch
14: use old request-waiting scheme instead of range locks

Vladimir Sementsov-Ogievskiy (5):
  block/backup: move in-flight requests handling from backup to
    block-copy
  block/backup: move write_flags calculation inside backup_job_create
  block/block-copy: split block_copy_set_callbacks function
  block: introduce backup-top filter driver
  block/backup: use backup-top instead of write notifiers

 qapi/block-core.json       |   8 +-
 block/backup-top.h         |  41 +++++
 include/block/block-copy.h |  31 +++-
 include/block/block_int.h  |   1 +
 block/backup-top.c         | 276 +++++++++++++++++++++++++++++++++
 block/backup.c             | 147 +++++-------------
 block/block-copy.c         | 140 +++++++++--------
 block/replication.c        |   2 +-
 blockdev.c                 |   1 +
 block/Makefile.objs        |   1 +
 tests/qemu-iotests/056     |   8 +-
 tests/qemu-iotests/141.out |   2 +-
 tests/qemu-iotests/257     |   7 +-
 tests/qemu-iotests/257.out | 306 ++++++++++++++++++-------------------
 14 files changed, 628 insertions(+), 343 deletions(-)
 create mode 100644 block/backup-top.h
 create mode 100644 block/backup-top.c

-- 
2.21.0

[PATCH v15 1/5] block/backup: move in-flight requests handling from backup to block-copy

[Vladimir Sementsov-Ogievskiy]

Move synchronization mechanism to block-copy, to be able to use one
block-copy instance from backup job and backup-top filter in parallel.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 include/block/block-copy.h |  8 ++++++
 block/backup.c             | 52 --------------------------------------
 block/block-copy.c         | 43 +++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+), 52 deletions(-)

diff --git a/include/block/block-copy.h b/include/block/block-copy.h
index 54f90d0c9a..962f91056a 100644
--- a/include/block/block-copy.h
+++ b/include/block/block-copy.h
@@ -17,6 +17,13 @@
 
 #include "block/block.h"
 
+typedef struct BlockCopyInFlightReq {
+    int64_t start_byte;
+    int64_t end_byte;
+    QLIST_ENTRY(BlockCopyInFlightReq) list;
+    CoQueue wait_queue; /* coroutines blocked on this request */
+} BlockCopyInFlightReq;
+
 typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque);
 typedef void (*ProgressResetCallbackFunc)(void *opaque);
 typedef struct BlockCopyState {
@@ -27,6 +34,7 @@ typedef struct BlockCopyState {
     bool use_copy_range;
     int64_t copy_range_size;
     uint64_t len;
+    QLIST_HEAD(, BlockCopyInFlightReq) inflight_reqs;
 
     BdrvRequestFlags write_flags;
 
diff --git a/block/backup.c b/block/backup.c
index 4613b8c88d..d918836f1d 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -29,13 +29,6 @@
 
 #define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16)
 
-typedef struct CowRequest {
-    int64_t start_byte;
-    int64_t end_byte;
-    QLIST_ENTRY(CowRequest) list;
-    CoQueue wait_queue; /* coroutines blocked on this request */
-} CowRequest;
-
 typedef struct BackupBlockJob {
     BlockJob common;
     BlockDriverState *source_bs;
@@ -51,50 +44,12 @@ typedef struct BackupBlockJob {
     uint64_t bytes_read;
     int64_t cluster_size;
     NotifierWithReturn before_write;
-    QLIST_HEAD(, CowRequest) inflight_reqs;
 
     BlockCopyState *bcs;
 } BackupBlockJob;
 
 static const BlockJobDriver backup_job_driver;
 
-/* See if in-flight requests overlap and wait for them to complete */
-static void coroutine_fn wait_for_overlapping_requests(BackupBlockJob *job,
-                                                       int64_t start,
-                                                       int64_t end)
-{
-    CowRequest *req;
-    bool retry;
-
-    do {
-        retry = false;
-        QLIST_FOREACH(req, &job->inflight_reqs, list) {
-            if (end > req->start_byte && start < req->end_byte) {
-                qemu_co_queue_wait(&req->wait_queue, NULL);
-                retry = true;
-                break;
-            }
-        }
-    } while (retry);
-}
-
-/* Keep track of an in-flight request */
-static void cow_request_begin(CowRequest *req, BackupBlockJob *job,
-                              int64_t start, int64_t end)
-{
-    req->start_byte = start;
-    req->end_byte = end;
-    qemu_co_queue_init(&req->wait_queue);
-    QLIST_INSERT_HEAD(&job->inflight_reqs, req, list);
-}
-
-/* Forget about a completed request */
-static void cow_request_end(CowRequest *req)
-{
-    QLIST_REMOVE(req, list);
-    qemu_co_queue_restart_all(&req->wait_queue);
-}
-
 static void backup_progress_bytes_callback(int64_t bytes, void *opaque)
 {
     BackupBlockJob *s = opaque;
@@ -116,7 +71,6 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
                                       bool *error_is_read,
                                       bool is_write_notifier)
 {
-    CowRequest cow_request;
     int ret = 0;
     int64_t start, end; /* bytes */
 
@@ -127,14 +81,9 @@ static int coroutine_fn backup_do_cow(BackupBlockJob *job,
 
     trace_backup_do_cow_enter(job, start, offset, bytes);
 
-    wait_for_overlapping_requests(job, start, end);
-    cow_request_begin(&cow_request, job, start, end);
-
     ret = block_copy(job->bcs, start, end - start, error_is_read,
                      is_write_notifier);
 
-    cow_request_end(&cow_request);
-
     trace_backup_do_cow_return(job, offset, bytes, ret);
 
     qemu_co_rwlock_unlock(&job->flush_rwlock);
@@ -316,7 +265,6 @@ static int coroutine_fn backup_run(Job *job, Error **errp)
     BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
     int ret = 0;
 
-    QLIST_INIT(&s->inflight_reqs);
     qemu_co_rwlock_init(&s->flush_rwlock);
 
     backup_init_copy_bitmap(s);
diff --git a/block/block-copy.c b/block/block-copy.c
index 3fc9152853..61e5ea5f46 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -19,6 +19,41 @@
 #include "block/block-copy.h"
 #include "sysemu/block-backend.h"
 
+static void coroutine_fn block_copy_wait_inflight_reqs(BlockCopyState *s,
+                                                       int64_t start,
+                                                       int64_t end)
+{
+    BlockCopyInFlightReq *req;
+    bool waited;
+
+    do {
+        waited = false;
+        QLIST_FOREACH(req, &s->inflight_reqs, list) {
+            if (end > req->start_byte && start < req->end_byte) {
+                qemu_co_queue_wait(&req->wait_queue, NULL);
+                waited = true;
+                break;
+            }
+        }
+    } while (waited);
+}
+
+static void block_copy_inflight_req_begin(BlockCopyState *s,
+                                          BlockCopyInFlightReq *req,
+                                          int64_t start, int64_t end)
+{
+    req->start_byte = start;
+    req->end_byte = end;
+    qemu_co_queue_init(&req->wait_queue);
+    QLIST_INSERT_HEAD(&s->inflight_reqs, req, list);
+}
+
+static void coroutine_fn block_copy_inflight_req_end(BlockCopyInFlightReq *req)
+{
+    QLIST_REMOVE(req, list);
+    qemu_co_queue_restart_all(&req->wait_queue);
+}
+
 void block_copy_state_free(BlockCopyState *s)
 {
     if (!s) {
@@ -79,6 +114,8 @@ BlockCopyState *block_copy_state_new(
     s->use_copy_range =
         !(write_flags & BDRV_REQ_WRITE_COMPRESSED) && s->copy_range_size > 0;
 
+    QLIST_INIT(&s->inflight_reqs);
+
     /*
      * We just allow aio context change on our block backends. block_copy() user
      * (now it's only backup) is responsible for source and target being in same
@@ -266,6 +303,7 @@ int coroutine_fn block_copy(BlockCopyState *s,
     int64_t end = bytes + start; /* bytes */
     void *bounce_buffer = NULL;
     int64_t status_bytes;
+    BlockCopyInFlightReq req;
 
     /*
      * block_copy() user is responsible for keeping source and target in same
@@ -276,6 +314,9 @@ int coroutine_fn block_copy(BlockCopyState *s,
     assert(QEMU_IS_ALIGNED(start, s->cluster_size));
     assert(QEMU_IS_ALIGNED(end, s->cluster_size));
 
+    block_copy_wait_inflight_reqs(s, start, bytes);
+    block_copy_inflight_req_begin(s, &req, start, end);
+
     while (start < end) {
         int64_t dirty_end;
 
@@ -329,5 +370,7 @@ int coroutine_fn block_copy(BlockCopyState *s,
         qemu_vfree(bounce_buffer);
     }
 
+    block_copy_inflight_req_end(&req);
+
     return ret;
 }
-- 
2.21.0

Re: [PATCH v15 1/5] block/backup: move in-flight requests handling from backup to block-copy

[Max Reitz]

[-- Attachment #1.1: Type: text/plain, Size: 575 bytes --]

On 01.10.19 15:14, Vladimir Sementsov-Ogievskiy wrote:
> Move synchronization mechanism to block-copy, to be able to use one
> block-copy instance from backup job and backup-top filter in parallel.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  include/block/block-copy.h |  8 ++++++
>  block/backup.c             | 52 --------------------------------------
>  block/block-copy.c         | 43 +++++++++++++++++++++++++++++++
>  3 files changed, 51 insertions(+), 52 deletions(-)

Reviewed-by: Max Reitz <mreitz@redhat.com>


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[PATCH v15 2/5] block/backup: move write_flags calculation inside backup_job_create

[Vladimir Sementsov-Ogievskiy]

This is logic-less refactoring, which simplifies further patch, as
we'll need write_flags for backup-top filter creation and backup-top
should be created before block job creation.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/backup.c | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/block/backup.c b/block/backup.c
index d918836f1d..b5b7939356 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -446,20 +446,6 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
         goto error;
     }
 
-    /* job->len is fixed, so we can't allow resize */
-    job = block_job_create(job_id, &backup_job_driver, txn, bs, 0, BLK_PERM_ALL,
-                           speed, creation_flags, cb, opaque, errp);
-    if (!job) {
-        goto error;
-    }
-
-    job->source_bs = bs;
-    job->on_source_error = on_source_error;
-    job->on_target_error = on_target_error;
-    job->sync_mode = sync_mode;
-    job->sync_bitmap = sync_bitmap;
-    job->bitmap_mode = bitmap_mode;
-
     /*
      * If source is in backing chain of target assume that target is going to be
      * used for "image fleecing", i.e. it should represent a kind of snapshot of
@@ -477,6 +463,20 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     write_flags = (bdrv_chain_contains(target, bs) ? BDRV_REQ_SERIALISING : 0) |
                   (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
 
+    /* job->len is fixed, so we can't allow resize */
+    job = block_job_create(job_id, &backup_job_driver, txn, bs, 0, BLK_PERM_ALL,
+                           speed, creation_flags, cb, opaque, errp);
+    if (!job) {
+        goto error;
+    }
+
+    job->source_bs = bs;
+    job->on_source_error = on_source_error;
+    job->on_target_error = on_target_error;
+    job->sync_mode = sync_mode;
+    job->sync_bitmap = sync_bitmap;
+    job->bitmap_mode = bitmap_mode;
+
     job->bcs = block_copy_state_new(bs, target, cluster_size, write_flags,
                                     backup_progress_bytes_callback,
                                     backup_progress_reset_callback, job, errp);
@@ -485,11 +485,11 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     }
 
     job->cluster_size = cluster_size;
+    job->len = len;
 
     /* Required permissions are already taken by block-copy-state target */
     block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
                        &error_abort);
-    job->len = len;
 
     return &job->common;
 
-- 
2.21.0

Re: [PATCH v15 2/5] block/backup: move write_flags calculation inside backup_job_create

[Max Reitz]

[-- Attachment #1.1: Type: text/plain, Size: 488 bytes --]

On 01.10.19 15:14, Vladimir Sementsov-Ogievskiy wrote:
> This is logic-less refactoring, which simplifies further patch, as
> we'll need write_flags for backup-top filter creation and backup-top
> should be created before block job creation.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  block/backup.c | 30 +++++++++++++++---------------
>  1 file changed, 15 insertions(+), 15 deletions(-)

Reviewed-by: Max Reitz <mreitz@redhat.com>


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[PATCH v15 3/5] block/block-copy: split block_copy_set_callbacks function

[Vladimir Sementsov-Ogievskiy]

Split block_copy_set_callbacks out of block_copy_state_new. It's needed
for further commit: block-copy will use BdrvChildren of backup-top
filter, so it will be created from backup-top filter creation function.
But callbacks will still belong to backup job and will be set in
separate.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 include/block/block-copy.h | 13 +++++++++----
 block/backup.c             |  6 ++++--
 block/block-copy.c         | 24 +++++++++++++++---------
 3 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/include/block/block-copy.h b/include/block/block-copy.h
index 962f91056a..340d856246 100644
--- a/include/block/block-copy.h
+++ b/include/block/block-copy.h
@@ -66,12 +66,17 @@ typedef struct BlockCopyState {
     void *progress_opaque;
 } BlockCopyState;
 
-BlockCopyState *block_copy_state_new(
-        BlockDriverState *source, BlockDriverState *target,
-        int64_t cluster_size, BdrvRequestFlags write_flags,
+BlockCopyState *block_copy_state_new(BlockDriverState *source,
+                                     BlockDriverState *target,
+                                     int64_t cluster_size,
+                                     BdrvRequestFlags write_flags,
+                                     Error **errp);
+
+void block_copy_set_callbacks(
+        BlockCopyState *s,
         ProgressBytesCallbackFunc progress_bytes_callback,
         ProgressResetCallbackFunc progress_reset_callback,
-        void *progress_opaque, Error **errp);
+        void *progress_opaque);
 
 void block_copy_state_free(BlockCopyState *s);
 
diff --git a/block/backup.c b/block/backup.c
index b5b7939356..1057ed0a4e 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -478,8 +478,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     job->bitmap_mode = bitmap_mode;
 
     job->bcs = block_copy_state_new(bs, target, cluster_size, write_flags,
-                                    backup_progress_bytes_callback,
-                                    backup_progress_reset_callback, job, errp);
+                                    errp);
     if (!job->bcs) {
         goto error;
     }
@@ -487,6 +486,9 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     job->cluster_size = cluster_size;
     job->len = len;
 
+    block_copy_set_callbacks(job->bcs, backup_progress_bytes_callback,
+                             backup_progress_reset_callback, job);
+
     /* Required permissions are already taken by block-copy-state target */
     block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
                        &error_abort);
diff --git a/block/block-copy.c b/block/block-copy.c
index 61e5ea5f46..fcb112da14 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -66,12 +66,10 @@ void block_copy_state_free(BlockCopyState *s)
     g_free(s);
 }
 
-BlockCopyState *block_copy_state_new(
-        BlockDriverState *source, BlockDriverState *target,
-        int64_t cluster_size, BdrvRequestFlags write_flags,
-        ProgressBytesCallbackFunc progress_bytes_callback,
-        ProgressResetCallbackFunc progress_reset_callback,
-        void *progress_opaque, Error **errp)
+BlockCopyState *block_copy_state_new(BlockDriverState *source,
+                                     BlockDriverState *target,
+                                     int64_t cluster_size,
+                                     BdrvRequestFlags write_flags, Error **errp)
 {
     BlockCopyState *s;
     int ret;
@@ -95,9 +93,6 @@ BlockCopyState *block_copy_state_new(
         .cluster_size = cluster_size,
         .len = bdrv_dirty_bitmap_size(copy_bitmap),
         .write_flags = write_flags,
-        .progress_bytes_callback = progress_bytes_callback,
-        .progress_reset_callback = progress_reset_callback,
-        .progress_opaque = progress_opaque,
     };
 
     s->copy_range_size = QEMU_ALIGN_DOWN(MIN(blk_get_max_transfer(s->source),
@@ -144,6 +139,17 @@ fail:
     return NULL;
 }
 
+void block_copy_set_callbacks(
+        BlockCopyState *s,
+        ProgressBytesCallbackFunc progress_bytes_callback,
+        ProgressResetCallbackFunc progress_reset_callback,
+        void *progress_opaque)
+{
+    s->progress_bytes_callback = progress_bytes_callback;
+    s->progress_reset_callback = progress_reset_callback;
+    s->progress_opaque = progress_opaque;
+}
+
 /*
  * Copy range to target with a bounce buffer and return the bytes copied. If
  * error occurred, return a negative error number
-- 
2.21.0

Re: [PATCH v15 3/5] block/block-copy: split block_copy_set_callbacks function

[Max Reitz]

[-- Attachment #1.1: Type: text/plain, Size: 699 bytes --]

On 01.10.19 15:14, Vladimir Sementsov-Ogievskiy wrote:
> Split block_copy_set_callbacks out of block_copy_state_new. It's needed
> for further commit: block-copy will use BdrvChildren of backup-top
> filter, so it will be created from backup-top filter creation function.
> But callbacks will still belong to backup job and will be set in
> separate.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  include/block/block-copy.h | 13 +++++++++----
>  block/backup.c             |  6 ++++--
>  block/block-copy.c         | 24 +++++++++++++++---------
>  3 files changed, 28 insertions(+), 15 deletions(-)

Reviewed-by: Max Reitz <mreitz@redhat.com>


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[PATCH v15 4/5] block: introduce backup-top filter driver

[Vladimir Sementsov-Ogievskiy]

Backup-top filter caches write operations and does copy-before-write
operations.

The driver will be used in backup instead of write-notifiers.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/backup-top.h  |  41 +++++++
 block/backup-top.c  | 281 ++++++++++++++++++++++++++++++++++++++++++++
 block/Makefile.objs |   1 +
 3 files changed, 323 insertions(+)
 create mode 100644 block/backup-top.h
 create mode 100644 block/backup-top.c

diff --git a/block/backup-top.h b/block/backup-top.h
new file mode 100644
index 0000000000..e5cabfa197
--- /dev/null
+++ b/block/backup-top.h
@@ -0,0 +1,41 @@
+/*
+ * backup-top filter driver
+ *
+ * The driver performs Copy-Before-Write (CBW) operation: it is injected above
+ * some node, and before each write it copies _old_ data to the target node.
+ *
+ * Copyright (c) 2018-2019 Virtuozzo International GmbH.
+ *
+ * Author:
+ *  Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef BACKUP_TOP_H
+#define BACKUP_TOP_H
+
+#include "block/block_int.h"
+#include "block/block-copy.h"
+
+BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
+                                         BlockDriverState *target,
+                                         const char *filter_node_name,
+                                         uint64_t cluster_size,
+                                         BdrvRequestFlags write_flags,
+                                         BlockCopyState **bcs,
+                                         Error **errp);
+void bdrv_backup_top_drop(BlockDriverState *bs);
+
+#endif /* BACKUP_TOP_H */
diff --git a/block/backup-top.c b/block/backup-top.c
new file mode 100644
index 0000000000..75a315744d
--- /dev/null
+++ b/block/backup-top.c
@@ -0,0 +1,281 @@
+/*
+ * backup-top filter driver
+ *
+ * The driver performs Copy-Before-Write (CBW) operation: it is injected above
+ * some node, and before each write it copies _old_ data to the target node.
+ *
+ * Copyright (c) 2018-2019 Virtuozzo International GmbH.
+ *
+ * Author:
+ *  Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+
+#include "sysemu/block-backend.h"
+#include "qemu/cutils.h"
+#include "qapi/error.h"
+#include "block/block_int.h"
+#include "block/qdict.h"
+#include "block/block-copy.h"
+
+#include "block/backup-top.h"
+
+typedef struct BDRVBackupTopState {
+    BlockCopyState *bcs;
+    BdrvChild *target;
+    bool active;
+} BDRVBackupTopState;
+
+static coroutine_fn int backup_top_co_preadv(
+        BlockDriverState *bs, uint64_t offset, uint64_t bytes,
+        QEMUIOVector *qiov, int flags)
+{
+    return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags);
+}
+
+static coroutine_fn int backup_top_cbw(BlockDriverState *bs, uint64_t offset,
+                                       uint64_t bytes)
+{
+    /*
+     * Here we'd like to use block_copy(), but block-copy need to be moved to
+     * use BdrvChildren to correctly use it in backup-top filter. It's a TODO.
+     */
+
+    abort();
+}
+
+static int coroutine_fn backup_top_co_pdiscard(BlockDriverState *bs,
+                                               int64_t offset, int bytes)
+{
+    int ret = backup_top_cbw(bs, offset, bytes);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return bdrv_co_pdiscard(bs->backing, offset, bytes);
+}
+
+static int coroutine_fn backup_top_co_pwrite_zeroes(BlockDriverState *bs,
+        int64_t offset, int bytes, BdrvRequestFlags flags)
+{
+    int ret = backup_top_cbw(bs, offset, bytes);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return bdrv_co_pwrite_zeroes(bs->backing, offset, bytes, flags);
+}
+
+static coroutine_fn int backup_top_co_pwritev(BlockDriverState *bs,
+                                              uint64_t offset,
+                                              uint64_t bytes,
+                                              QEMUIOVector *qiov, int flags)
+{
+    if (!(flags & BDRV_REQ_WRITE_UNCHANGED)) {
+        int ret = backup_top_cbw(bs, offset, bytes);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    return bdrv_co_pwritev(bs->backing, offset, bytes, qiov, flags);
+}
+
+static int coroutine_fn backup_top_co_flush(BlockDriverState *bs)
+{
+    if (!bs->backing) {
+        return 0;
+    }
+
+    return bdrv_co_flush(bs->backing->bs);
+}
+
+static void backup_top_refresh_filename(BlockDriverState *bs)
+{
+    if (bs->backing == NULL) {
+        /*
+         * we can be here after failed bdrv_attach_child in
+         * bdrv_set_backing_hd
+         */
+        return;
+    }
+    pstrcpy(bs->exact_filename, sizeof(bs->exact_filename),
+            bs->backing->bs->filename);
+}
+
+static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c,
+                                  const BdrvChildRole *role,
+                                  BlockReopenQueue *reopen_queue,
+                                  uint64_t perm, uint64_t shared,
+                                  uint64_t *nperm, uint64_t *nshared)
+{
+    BDRVBackupTopState *s = bs->opaque;
+
+    if (!s->active) {
+        /*
+         * The filter node may be in process of bdrv_append(), which firstly do
+         * bdrv_set_backing_hd() and then bdrv_replace_node(). This means that
+         * we can't unshare BLK_PERM_WRITE during bdrv_append() operation. So,
+         * let's require nothing during bdrv_append() and refresh permissions
+         * after it (see bdrv_backup_top_append()).
+         */
+        *nperm = 0;
+        *nshared = BLK_PERM_ALL;
+        return;
+    }
+
+    if (role == &child_file) {
+        /*
+         * Target child
+         *
+         * Share write to target (child_file), to not interfere
+         * with guest writes to its disk which may be in target backing chain.
+         */
+        *nshared = BLK_PERM_ALL;
+        *nperm = BLK_PERM_WRITE;
+    } else {
+        /* Source child */
+        bdrv_filter_default_perms(bs, c, role, reopen_queue, perm, shared,
+                                  nperm, nshared);
+
+        if (perm & BLK_PERM_WRITE) {
+            *nperm = *nperm | BLK_PERM_CONSISTENT_READ;
+        }
+        *nshared &= ~BLK_PERM_WRITE;
+    }
+}
+
+BlockDriver bdrv_backup_top_filter = {
+    .format_name = "backup-top",
+    .instance_size = sizeof(BDRVBackupTopState),
+
+    .bdrv_co_preadv             = backup_top_co_preadv,
+    .bdrv_co_pwritev            = backup_top_co_pwritev,
+    .bdrv_co_pwrite_zeroes      = backup_top_co_pwrite_zeroes,
+    .bdrv_co_pdiscard           = backup_top_co_pdiscard,
+    .bdrv_co_flush              = backup_top_co_flush,
+
+    .bdrv_co_block_status       = bdrv_co_block_status_from_backing,
+
+    .bdrv_refresh_filename      = backup_top_refresh_filename,
+
+    .bdrv_child_perm            = backup_top_child_perm,
+
+    .is_filter = true,
+};
+
+BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
+                                         BlockDriverState *target,
+                                         const char *filter_node_name,
+                                         uint64_t cluster_size,
+                                         BdrvRequestFlags write_flags,
+                                         BlockCopyState **bcs,
+                                         Error **errp)
+{
+    Error *local_err = NULL;
+    BDRVBackupTopState *state;
+    BlockDriverState *top = bdrv_new_open_driver(&bdrv_backup_top_filter,
+                                                 filter_node_name,
+                                                 BDRV_O_RDWR, errp);
+
+    if (!top) {
+        return NULL;
+    }
+
+    top->total_sectors = source->total_sectors;
+    top->opaque = state = g_new0(BDRVBackupTopState, 1);
+
+    bdrv_ref(target);
+    state->target = bdrv_attach_child(top, target, "target", &child_file, errp);
+    if (!state->target) {
+        bdrv_unref(target);
+        bdrv_unref(top);
+        return NULL;
+    }
+
+    bdrv_drained_begin(source);
+
+    bdrv_ref(top);
+    bdrv_append(top, source, &local_err);
+    if (local_err) {
+        error_prepend(&local_err, "Cannot append backup-top filter: ");
+        goto append_failed;
+    }
+
+    /*
+     * bdrv_append() finished successfully, now we can require permissions
+     * we want.
+     */
+    state->active = true;
+    bdrv_child_refresh_perms(top, top->backing, &local_err);
+    if (local_err) {
+        error_prepend(&local_err,
+                      "Cannot set permissions for backup-top filter: ");
+        goto failed_after_append;
+    }
+
+    /*
+     * TODO: Create block-copy-state here (which will utilize @cluster_size and
+     * @write_flags parameters which are unused now). For this, block-copy
+     * should be refactored to use BdrvChildren.
+     */
+    state->bcs = NULL;
+    if (!state->bcs) {
+        error_setg(&local_err, "Cannot create block-copy-state");
+        goto failed_after_append;
+    }
+    *bcs = state->bcs;
+
+    bdrv_drained_end(source);
+
+    return top;
+
+failed_after_append:
+    state->active = false;
+    bdrv_backup_top_drop(top);
+
+append_failed:
+    bdrv_drained_end(source);
+    bdrv_unref_child(top, state->target);
+    bdrv_unref(top);
+    error_propagate(errp, local_err);
+
+    return NULL;
+}
+
+void bdrv_backup_top_drop(BlockDriverState *bs)
+{
+    BDRVBackupTopState *s = bs->opaque;
+    AioContext *aio_context = bdrv_get_aio_context(bs);
+
+    block_copy_state_free(s->bcs);
+
+    aio_context_acquire(aio_context);
+
+    bdrv_drained_begin(bs);
+
+    s->active = false;
+    bdrv_child_refresh_perms(bs, bs->backing, &error_abort);
+    bdrv_replace_node(bs, backing_bs(bs), &error_abort);
+    bdrv_set_backing_hd(bs, NULL, &error_abort);
+
+    bdrv_drained_end(bs);
+
+    bdrv_unref(bs);
+
+    aio_context_release(aio_context);
+}
diff --git a/block/Makefile.objs b/block/Makefile.objs
index f06f1fa1ac..e394fe0b6c 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -42,6 +42,7 @@ block-obj-y += block-copy.o
 block-obj-y += crypto.o
 
 block-obj-y += aio_task.o
+block-obj-y += backup-top.o
 
 common-obj-y += stream.o
 
-- 
2.21.0

Re: [PATCH v15 4/5] block: introduce backup-top filter driver

[Max Reitz]

[-- Attachment #1.1: Type: text/plain, Size: 613 bytes --]

On 01.10.19 15:14, Vladimir Sementsov-Ogievskiy wrote:
> Backup-top filter caches write operations and does copy-before-write
> operations.
> 
> The driver will be used in backup instead of write-notifiers.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  block/backup-top.h  |  41 +++++++
>  block/backup-top.c  | 281 ++++++++++++++++++++++++++++++++++++++++++++
>  block/Makefile.objs |   1 +
>  3 files changed, 323 insertions(+)
>  create mode 100644 block/backup-top.h
>  create mode 100644 block/backup-top.c

Reviewed-by: Max Reitz <mreitz@redhat.com>


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

[PATCH v15 5/5] block/backup: use backup-top instead of write notifiers

[Vladimir Sementsov-Ogievskiy]

Drop write notifiers and use filter node instead.

= Changes =

1. Add filter-node-name argument for backup qmp api. We have to do it
in this commit, as 257 needs to be fixed.

2. There are no more write notifiers here, so is_write_notifier
parameter is dropped from block-copy paths.

3. To sync with in-flight requests at job finish we now have drained
removing of the filter, we don't need rw-lock.

4. Block-copy is now using BdrvChildren instead of BlockBackends

5. As backup-top owns these children, we also move block-copy state
into backup-top's ownership.

= Iotest changes =

56: op-blocker doesn't shoot now, as we set it on source, but then
check on filter, when trying to start second backup.
To keep the test we instead can catch another collision: both jobs will
get 'drive0' job-id, as job-id parameter is unspecified. To prevent
interleaving with file-posix locks (as they are dependent on config)
let's use another target for second backup.

Also, it's obvious now that we'd like to drop this op-blocker at all
and add a test-case for two backups from one node (to different
destinations) actually works. But not in these series.

141: Output changed: prepatch, "Node is in use" comes from bdrv_has_blk
check inside qmp_blockdev_del. But we've dropped block-copy blk
objects, so no more blk objects on source bs (job blk is on backup-top
filter bs). New message is from op-blocker, which is the next check in
qmp_blockdev_add.

257: The test wants to emulate guest write during backup. They should
go to filter node, not to original source node, of course. Therefore we
need to specify filter node name and use it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 qapi/block-core.json       |   8 +-
 include/block/block-copy.h |  14 +-
 include/block/block_int.h  |   1 +
 block/backup-top.c         |  21 +--
 block/backup.c             |  73 +++------
 block/block-copy.c         |  81 +++-------
 block/replication.c        |   2 +-
 blockdev.c                 |   1 +
 tests/qemu-iotests/056     |   8 +-
 tests/qemu-iotests/141.out |   2 +-
 tests/qemu-iotests/257     |   7 +-
 tests/qemu-iotests/257.out | 306 ++++++++++++++++++-------------------
 12 files changed, 237 insertions(+), 287 deletions(-)

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 859acea014..f66553aac7 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -1450,6 +1450,11 @@
 #                list without user intervention.
 #                Defaults to true. (Since 2.12)
 #
+# @filter-node-name: the node name that should be assigned to the
+#                    filter driver that the backup job inserts into the graph
+#                    above node specified by @drive. If this option is not given,
+#                    a node name is autogenerated. (Since: 4.2)
+#
 # Note: @on-source-error and @on-target-error only affect background
 # I/O.  If an error occurs during a guest write request, the device's
 # rerror/werror actions will be used.
@@ -1463,7 +1468,8 @@
             '*compress': 'bool',
             '*on-source-error': 'BlockdevOnError',
             '*on-target-error': 'BlockdevOnError',
-            '*auto-finalize': 'bool', '*auto-dismiss': 'bool' } }
+            '*auto-finalize': 'bool', '*auto-dismiss': 'bool',
+            '*filter-node-name': 'str' } }
 
 ##
 # @DriveBackup:
diff --git a/include/block/block-copy.h b/include/block/block-copy.h
index 340d856246..e2e135ff1b 100644
--- a/include/block/block-copy.h
+++ b/include/block/block-copy.h
@@ -27,8 +27,13 @@ typedef struct BlockCopyInFlightReq {
 typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque);
 typedef void (*ProgressResetCallbackFunc)(void *opaque);
 typedef struct BlockCopyState {
-    BlockBackend *source;
-    BlockBackend *target;
+    /*
+     * BdrvChild objects are not owned or managed by block-copy. They are
+     * provided by block-copy user and user is responsible for appropriate
+     * permissions on these children.
+     */
+    BdrvChild *source;
+    BdrvChild *target;
     BdrvDirtyBitmap *copy_bitmap;
     int64_t cluster_size;
     bool use_copy_range;
@@ -66,8 +71,7 @@ typedef struct BlockCopyState {
     void *progress_opaque;
 } BlockCopyState;
 
-BlockCopyState *block_copy_state_new(BlockDriverState *source,
-                                     BlockDriverState *target,
+BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
                                      int64_t cluster_size,
                                      BdrvRequestFlags write_flags,
                                      Error **errp);
@@ -84,6 +88,6 @@ int64_t block_copy_reset_unallocated(BlockCopyState *s,
                                      int64_t offset, int64_t *count);
 
 int coroutine_fn block_copy(BlockCopyState *s, int64_t start, uint64_t bytes,
-                            bool *error_is_read, bool is_write_notifier);
+                            bool *error_is_read);
 
 #endif /* BLOCK_COPY_H */
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 2b113eb3c7..05056b308a 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -1197,6 +1197,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
                             BdrvDirtyBitmap *sync_bitmap,
                             BitmapSyncMode bitmap_mode,
                             bool compress,
+                            const char *filter_node_name,
                             BlockdevOnError on_source_error,
                             BlockdevOnError on_target_error,
                             int creation_flags,
diff --git a/block/backup-top.c b/block/backup-top.c
index 75a315744d..7cdb1f8eba 100644
--- a/block/backup-top.c
+++ b/block/backup-top.c
@@ -50,12 +50,11 @@ static coroutine_fn int backup_top_co_preadv(
 static coroutine_fn int backup_top_cbw(BlockDriverState *bs, uint64_t offset,
                                        uint64_t bytes)
 {
-    /*
-     * Here we'd like to use block_copy(), but block-copy need to be moved to
-     * use BdrvChildren to correctly use it in backup-top filter. It's a TODO.
-     */
+    BDRVBackupTopState *s = bs->opaque;
+    uint64_t end = QEMU_ALIGN_UP(offset + bytes, s->bcs->cluster_size);
+    uint64_t off = QEMU_ALIGN_DOWN(offset, s->bcs->cluster_size);
 
-    abort();
+    return block_copy(s->bcs, off, end - off, NULL);
 }
 
 static int coroutine_fn backup_top_co_pdiscard(BlockDriverState *bs,
@@ -228,14 +227,10 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
         goto failed_after_append;
     }
 
-    /*
-     * TODO: Create block-copy-state here (which will utilize @cluster_size and
-     * @write_flags parameters which are unused now). For this, block-copy
-     * should be refactored to use BdrvChildren.
-     */
-    state->bcs = NULL;
-    if (!state->bcs) {
-        error_setg(&local_err, "Cannot create block-copy-state");
+    state->bcs = block_copy_state_new(top->backing, state->target,
+                                      cluster_size, write_flags, &local_err);
+    if (local_err) {
+        error_prepend(&local_err, "Cannot create block-copy-state: ");
         goto failed_after_append;
     }
     *bcs = state->bcs;
diff --git a/block/backup.c b/block/backup.c
index 1057ed0a4e..46978c1785 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -2,6 +2,7 @@
  * QEMU backup
  *
  * Copyright (C) 2013 Proxmox Server Solutions
+ * Copyright (c) 2019 Virtuozzo International GmbH.
  *
  * Authors:
  *  Dietmar Maurer (dietmar@proxmox.com)
@@ -27,10 +28,13 @@
 #include "qemu/bitmap.h"
 #include "qemu/error-report.h"
 
+#include "block/backup-top.h"
+
 #define BACKUP_CLUSTER_SIZE_DEFAULT (1 << 16)
 
 typedef struct BackupBlockJob {
     BlockJob common;
+    BlockDriverState *backup_top;
     BlockDriverState *source_bs;
 
     BdrvDirtyBitmap *sync_bitmap;
@@ -39,11 +43,9 @@ typedef struct BackupBlockJob {
     BitmapSyncMode bitmap_mode;
     BlockdevOnError on_source_error;
     BlockdevOnError on_target_error;
-    CoRwlock flush_rwlock;
     uint64_t len;
     uint64_t bytes_read;
     int64_t cluster_size;
-    NotifierWithReturn before_write;
 
     BlockCopyState *bcs;
 } BackupBlockJob;
@@ -68,43 +70,23 @@ static void backup_progress_reset_callback(void *opaque)
 
 static int coroutine_fn backup_do_cow(BackupBlockJob *job,
                                       int64_t offset, uint64_t bytes,
-                                      bool *error_is_read,
-                                      bool is_write_notifier)
+                                      bool *error_is_read)
 {
     int ret = 0;
     int64_t start, end; /* bytes */
 
-    qemu_co_rwlock_rdlock(&job->flush_rwlock);
-
     start = QEMU_ALIGN_DOWN(offset, job->cluster_size);
     end = QEMU_ALIGN_UP(bytes + offset, job->cluster_size);
 
     trace_backup_do_cow_enter(job, start, offset, bytes);
 
-    ret = block_copy(job->bcs, start, end - start, error_is_read,
-                     is_write_notifier);
+    ret = block_copy(job->bcs, start, end - start, error_is_read);
 
     trace_backup_do_cow_return(job, offset, bytes, ret);
 
-    qemu_co_rwlock_unlock(&job->flush_rwlock);
-
     return ret;
 }
 
-static int coroutine_fn backup_before_write_notify(
-        NotifierWithReturn *notifier,
-        void *opaque)
-{
-    BackupBlockJob *job = container_of(notifier, BackupBlockJob, before_write);
-    BdrvTrackedRequest *req = opaque;
-
-    assert(req->bs == job->source_bs);
-    assert(QEMU_IS_ALIGNED(req->offset, BDRV_SECTOR_SIZE));
-    assert(QEMU_IS_ALIGNED(req->bytes, BDRV_SECTOR_SIZE));
-
-    return backup_do_cow(job, req->offset, req->bytes, NULL, true);
-}
-
 static void backup_cleanup_sync_bitmap(BackupBlockJob *job, int ret)
 {
     BdrvDirtyBitmap *bm;
@@ -154,7 +136,7 @@ static void backup_clean(Job *job)
 {
     BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
 
-    block_copy_state_free(s->bcs);
+    bdrv_backup_top_drop(s->backup_top);
 }
 
 void backup_do_checkpoint(BlockJob *job, Error **errp)
@@ -220,8 +202,7 @@ static int coroutine_fn backup_loop(BackupBlockJob *job)
             if (yield_and_check(job)) {
                 goto out;
             }
-            ret = backup_do_cow(job, offset,
-                                job->cluster_size, &error_is_read, false);
+            ret = backup_do_cow(job, offset, job->cluster_size, &error_is_read);
             if (ret < 0 && backup_error_action(job, error_is_read, -ret) ==
                            BLOCK_ERROR_ACTION_REPORT)
             {
@@ -265,13 +246,8 @@ static int coroutine_fn backup_run(Job *job, Error **errp)
     BackupBlockJob *s = container_of(job, BackupBlockJob, common.job);
     int ret = 0;
 
-    qemu_co_rwlock_init(&s->flush_rwlock);
-
     backup_init_copy_bitmap(s);
 
-    s->before_write.notify = backup_before_write_notify;
-    bdrv_add_before_write_notifier(s->source_bs, &s->before_write);
-
     if (s->sync_mode == MIRROR_SYNC_MODE_TOP) {
         int64_t offset = 0;
         int64_t count;
@@ -309,12 +285,6 @@ static int coroutine_fn backup_run(Job *job, Error **errp)
     }
 
  out:
-    notifier_with_return_remove(&s->before_write);
-
-    /* wait until pending backup_do_cow() calls have completed */
-    qemu_co_rwlock_wrlock(&s->flush_rwlock);
-    qemu_co_rwlock_unlock(&s->flush_rwlock);
-
     return ret;
 }
 
@@ -372,6 +342,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
                   MirrorSyncMode sync_mode, BdrvDirtyBitmap *sync_bitmap,
                   BitmapSyncMode bitmap_mode,
                   bool compress,
+                  const char *filter_node_name,
                   BlockdevOnError on_source_error,
                   BlockdevOnError on_target_error,
                   int creation_flags,
@@ -382,6 +353,8 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     BackupBlockJob *job = NULL;
     int64_t cluster_size;
     BdrvRequestFlags write_flags;
+    BlockDriverState *backup_top = NULL;
+    BlockCopyState *bcs = NULL;
 
     assert(bs);
     assert(target);
@@ -463,33 +436,35 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     write_flags = (bdrv_chain_contains(target, bs) ? BDRV_REQ_SERIALISING : 0) |
                   (compress ? BDRV_REQ_WRITE_COMPRESSED : 0),
 
+    backup_top = bdrv_backup_top_append(bs, target, filter_node_name,
+                                        cluster_size, write_flags, &bcs, errp);
+    if (!backup_top) {
+        goto error;
+    }
+
     /* job->len is fixed, so we can't allow resize */
-    job = block_job_create(job_id, &backup_job_driver, txn, bs, 0, BLK_PERM_ALL,
+    job = block_job_create(job_id, &backup_job_driver, txn, backup_top,
+                           0, BLK_PERM_ALL,
                            speed, creation_flags, cb, opaque, errp);
     if (!job) {
         goto error;
     }
 
+    job->backup_top = backup_top;
     job->source_bs = bs;
     job->on_source_error = on_source_error;
     job->on_target_error = on_target_error;
     job->sync_mode = sync_mode;
     job->sync_bitmap = sync_bitmap;
     job->bitmap_mode = bitmap_mode;
-
-    job->bcs = block_copy_state_new(bs, target, cluster_size, write_flags,
-                                    errp);
-    if (!job->bcs) {
-        goto error;
-    }
-
+    job->bcs = bcs;
     job->cluster_size = cluster_size;
     job->len = len;
 
-    block_copy_set_callbacks(job->bcs, backup_progress_bytes_callback,
+    block_copy_set_callbacks(bcs, backup_progress_bytes_callback,
                              backup_progress_reset_callback, job);
 
-    /* Required permissions are already taken by block-copy-state target */
+    /* Required permissions are already taken by backup-top target */
     block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
                        &error_abort);
 
@@ -502,6 +477,8 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     if (job) {
         backup_clean(&job->common.job);
         job_early_fail(&job->common.job);
+    } else if (backup_top) {
+        bdrv_backup_top_drop(backup_top);
     }
 
     return NULL;
diff --git a/block/block-copy.c b/block/block-copy.c
index fcb112da14..5404bc921d 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -60,24 +60,22 @@ void block_copy_state_free(BlockCopyState *s)
         return;
     }
 
-    bdrv_release_dirty_bitmap(blk_bs(s->source), s->copy_bitmap);
-    blk_unref(s->source);
-    blk_unref(s->target);
+    bdrv_release_dirty_bitmap(s->source->bs, s->copy_bitmap);
     g_free(s);
 }
 
-BlockCopyState *block_copy_state_new(BlockDriverState *source,
-                                     BlockDriverState *target,
+BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
                                      int64_t cluster_size,
                                      BdrvRequestFlags write_flags, Error **errp)
 {
     BlockCopyState *s;
-    int ret;
-    uint64_t no_resize = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE |
-                         BLK_PERM_WRITE_UNCHANGED | BLK_PERM_GRAPH_MOD;
     BdrvDirtyBitmap *copy_bitmap;
+    uint32_t max_transfer =
+            MIN_NON_ZERO(INT_MAX, MIN_NON_ZERO(source->bs->bl.max_transfer,
+                                               target->bs->bl.max_transfer));
 
-    copy_bitmap = bdrv_create_dirty_bitmap(source, cluster_size, NULL, errp);
+    copy_bitmap = bdrv_create_dirty_bitmap(source->bs, cluster_size, NULL,
+                                           errp);
     if (!copy_bitmap) {
         return NULL;
     }
@@ -85,19 +83,15 @@ BlockCopyState *block_copy_state_new(BlockDriverState *source,
 
     s = g_new(BlockCopyState, 1);
     *s = (BlockCopyState) {
-        .source = blk_new(bdrv_get_aio_context(source),
-                          BLK_PERM_CONSISTENT_READ, no_resize),
-        .target = blk_new(bdrv_get_aio_context(target),
-                          BLK_PERM_WRITE, no_resize),
+        .source = source,
+        .target = target,
         .copy_bitmap = copy_bitmap,
         .cluster_size = cluster_size,
         .len = bdrv_dirty_bitmap_size(copy_bitmap),
         .write_flags = write_flags,
     };
 
-    s->copy_range_size = QEMU_ALIGN_DOWN(MIN(blk_get_max_transfer(s->source),
-                                             blk_get_max_transfer(s->target)),
-                                         s->cluster_size);
+    s->copy_range_size = QEMU_ALIGN_DOWN(max_transfer, cluster_size),
     /*
      * Set use_copy_range, consider the following:
      * 1. Compression is not supported for copy_range.
@@ -111,32 +105,7 @@ BlockCopyState *block_copy_state_new(BlockDriverState *source,
 
     QLIST_INIT(&s->inflight_reqs);
 
-    /*
-     * We just allow aio context change on our block backends. block_copy() user
-     * (now it's only backup) is responsible for source and target being in same
-     * aio context.
-     */
-    blk_set_disable_request_queuing(s->source, true);
-    blk_set_allow_aio_context_change(s->source, true);
-    blk_set_disable_request_queuing(s->target, true);
-    blk_set_allow_aio_context_change(s->target, true);
-
-    ret = blk_insert_bs(s->source, source, errp);
-    if (ret < 0) {
-        goto fail;
-    }
-
-    ret = blk_insert_bs(s->target, target, errp);
-    if (ret < 0) {
-        goto fail;
-    }
-
     return s;
-
-fail:
-    block_copy_state_free(s);
-
-    return NULL;
 }
 
 void block_copy_set_callbacks(
@@ -157,22 +126,20 @@ void block_copy_set_callbacks(
 static int coroutine_fn block_copy_with_bounce_buffer(BlockCopyState *s,
                                                       int64_t start,
                                                       int64_t end,
-                                                      bool is_write_notifier,
                                                       bool *error_is_read,
                                                       void **bounce_buffer)
 {
     int ret;
     int nbytes;
-    int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
 
     assert(QEMU_IS_ALIGNED(start, s->cluster_size));
     bdrv_reset_dirty_bitmap(s->copy_bitmap, start, s->cluster_size);
     nbytes = MIN(s->cluster_size, s->len - start);
     if (!*bounce_buffer) {
-        *bounce_buffer = blk_blockalign(s->source, s->cluster_size);
+        *bounce_buffer = qemu_blockalign(s->source->bs, s->cluster_size);
     }
 
-    ret = blk_co_pread(s->source, start, nbytes, *bounce_buffer, read_flags);
+    ret = bdrv_co_pread(s->source, start, nbytes, *bounce_buffer, 0);
     if (ret < 0) {
         trace_block_copy_with_bounce_buffer_read_fail(s, start, ret);
         if (error_is_read) {
@@ -181,8 +148,8 @@ static int coroutine_fn block_copy_with_bounce_buffer(BlockCopyState *s,
         goto fail;
     }
 
-    ret = blk_co_pwrite(s->target, start, nbytes, *bounce_buffer,
-                        s->write_flags);
+    ret = bdrv_co_pwrite(s->target, start, nbytes, *bounce_buffer,
+                         s->write_flags);
     if (ret < 0) {
         trace_block_copy_with_bounce_buffer_write_fail(s, start, ret);
         if (error_is_read) {
@@ -204,13 +171,11 @@ fail:
  */
 static int coroutine_fn block_copy_with_offload(BlockCopyState *s,
                                                 int64_t start,
-                                                int64_t end,
-                                                bool is_write_notifier)
+                                                int64_t end)
 {
     int ret;
     int nr_clusters;
     int nbytes;
-    int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
 
     assert(QEMU_IS_ALIGNED(s->copy_range_size, s->cluster_size));
     assert(QEMU_IS_ALIGNED(start, s->cluster_size));
@@ -218,8 +183,8 @@ static int coroutine_fn block_copy_with_offload(BlockCopyState *s,
     nr_clusters = DIV_ROUND_UP(nbytes, s->cluster_size);
     bdrv_reset_dirty_bitmap(s->copy_bitmap, start,
                             s->cluster_size * nr_clusters);
-    ret = blk_co_copy_range(s->source, start, s->target, start, nbytes,
-                            read_flags, s->write_flags);
+    ret = bdrv_co_copy_range(s->source, start, s->target, start, nbytes,
+                            0, s->write_flags);
     if (ret < 0) {
         trace_block_copy_with_offload_fail(s, start, ret);
         bdrv_set_dirty_bitmap(s->copy_bitmap, start,
@@ -237,7 +202,7 @@ static int coroutine_fn block_copy_with_offload(BlockCopyState *s,
 static int block_copy_is_cluster_allocated(BlockCopyState *s, int64_t offset,
                                            int64_t *pnum)
 {
-    BlockDriverState *bs = blk_bs(s->source);
+    BlockDriverState *bs = s->source->bs;
     int64_t count, total_count = 0;
     int64_t bytes = s->len - offset;
     int ret;
@@ -302,8 +267,7 @@ int64_t block_copy_reset_unallocated(BlockCopyState *s,
 
 int coroutine_fn block_copy(BlockCopyState *s,
                             int64_t start, uint64_t bytes,
-                            bool *error_is_read,
-                            bool is_write_notifier)
+                            bool *error_is_read)
 {
     int ret = 0;
     int64_t end = bytes + start; /* bytes */
@@ -315,7 +279,8 @@ int coroutine_fn block_copy(BlockCopyState *s,
      * block_copy() user is responsible for keeping source and target in same
      * aio context
      */
-    assert(blk_get_aio_context(s->source) == blk_get_aio_context(s->target));
+    assert(bdrv_get_aio_context(s->source->bs) ==
+           bdrv_get_aio_context(s->target->bs));
 
     assert(QEMU_IS_ALIGNED(start, s->cluster_size));
     assert(QEMU_IS_ALIGNED(end, s->cluster_size));
@@ -352,15 +317,13 @@ int coroutine_fn block_copy(BlockCopyState *s,
         trace_block_copy_process(s, start);
 
         if (s->use_copy_range) {
-            ret = block_copy_with_offload(s, start, dirty_end,
-                                          is_write_notifier);
+            ret = block_copy_with_offload(s, start, dirty_end);
             if (ret < 0) {
                 s->use_copy_range = false;
             }
         }
         if (!s->use_copy_range) {
             ret = block_copy_with_bounce_buffer(s, start, dirty_end,
-                                                is_write_notifier,
                                                 error_is_read, &bounce_buffer);
         }
         if (ret < 0) {
diff --git a/block/replication.c b/block/replication.c
index 936b2f8b5a..99532ce521 100644
--- a/block/replication.c
+++ b/block/replication.c
@@ -543,7 +543,7 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode,
 
         s->backup_job = backup_job_create(
                                 NULL, s->secondary_disk->bs, s->hidden_disk->bs,
-                                0, MIRROR_SYNC_MODE_NONE, NULL, 0, false,
+                                0, MIRROR_SYNC_MODE_NONE, NULL, 0, false, NULL,
                                 BLOCKDEV_ON_ERROR_REPORT,
                                 BLOCKDEV_ON_ERROR_REPORT, JOB_INTERNAL,
                                 backup_job_completed, bs, NULL, &local_err);
diff --git a/blockdev.c b/blockdev.c
index fbef6845c8..f89e48fc79 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -3601,6 +3601,7 @@ static BlockJob *do_backup_common(BackupCommon *backup,
     job = backup_job_create(backup->job_id, bs, target_bs, backup->speed,
                             backup->sync, bmap, backup->bitmap_mode,
                             backup->compress,
+                            backup->filter_node_name,
                             backup->on_source_error,
                             backup->on_target_error,
                             job_flags, NULL, NULL, txn, errp);
diff --git a/tests/qemu-iotests/056 b/tests/qemu-iotests/056
index 98c55d8e5a..f39287c162 100755
--- a/tests/qemu-iotests/056
+++ b/tests/qemu-iotests/056
@@ -133,6 +133,7 @@ class BackupTest(iotests.QMPTestCase):
         self.vm = iotests.VM()
         self.test_img = img_create('test')
         self.dest_img = img_create('dest')
+        self.dest_img2 = img_create('dest2')
         self.ref_img = img_create('ref')
         self.vm.add_drive(self.test_img)
         self.vm.launch()
@@ -141,6 +142,7 @@ class BackupTest(iotests.QMPTestCase):
         self.vm.shutdown()
         try_remove(self.test_img)
         try_remove(self.dest_img)
+        try_remove(self.dest_img2)
         try_remove(self.ref_img)
 
     def hmp_io_writes(self, drive, patterns):
@@ -253,9 +255,9 @@ class BackupTest(iotests.QMPTestCase):
         res = self.vm.qmp('query-block-jobs')
         self.assert_qmp(res, 'return[0]/status', 'concluded')
         # Leave zombie job un-dismissed, observe a failure:
-        res = self.qmp_backup_and_wait(serror="Node 'drive0' is busy: block device is in use by block job: backup",
+        res = self.qmp_backup_and_wait(serror="Job ID 'drive0' already in use",
                                        device='drive0', format=iotests.imgfmt,
-                                       sync='full', target=self.dest_img,
+                                       sync='full', target=self.dest_img2,
                                        auto_dismiss=False)
         self.assertEqual(res, False)
         # OK, dismiss the zombie.
@@ -265,7 +267,7 @@ class BackupTest(iotests.QMPTestCase):
         self.assert_qmp(res, 'return', [])
         # Ensure it's really gone.
         self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
-                                 sync='full', target=self.dest_img,
+                                 sync='full', target=self.dest_img2,
                                  auto_dismiss=False)
 
     def dismissal_failure(self, dismissal_opt):
diff --git a/tests/qemu-iotests/141.out b/tests/qemu-iotests/141.out
index dbd3bdef6c..e3b578282d 100644
--- a/tests/qemu-iotests/141.out
+++ b/tests/qemu-iotests/141.out
@@ -10,7 +10,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 backing_file=TEST_DIR/m.
 Formatting 'TEST_DIR/o.IMGFMT', fmt=IMGFMT size=1048576 backing_file=TEST_DIR/t.IMGFMT backing_fmt=IMGFMT
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "created", "id": "job0"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "running", "id": "job0"}}
-{"error": {"class": "GenericError", "desc": "Node drv0 is in use"}}
+{"error": {"class": "GenericError", "desc": "Node 'drv0' is busy: node is used as backing hd of 'NODE_NAME'"}}
 {"return": {}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "aborting", "id": "job0"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "BLOCK_JOB_CANCELLED", "data": {"device": "job0", "len": 1048576, "offset": 0, "speed": 0, "type": "backup"}}
diff --git a/tests/qemu-iotests/257 b/tests/qemu-iotests/257
index de8b45f094..a9828251cf 100755
--- a/tests/qemu-iotests/257
+++ b/tests/qemu-iotests/257
@@ -190,6 +190,7 @@ def blockdev_backup(vm, device, target, sync, **kwargs):
                         device=device,
                         target=target,
                         sync=sync,
+                        filter_node_name='backup-top',
                         **kwargs)
     return result
 
@@ -216,7 +217,7 @@ def backup(drive, n, filepath, sync, **kwargs):
                              job_id=job_id, **kwargs)
     return job_id
 
-def perform_writes(drive, n):
+def perform_writes(drive, n, filter_node_name=None):
     log("--- Write #{:d} ---\n".format(n))
     for pattern in GROUPS[n].patterns:
         cmd = "write -P{:s} 0x{:07x} 0x{:x}".format(
@@ -224,7 +225,7 @@ def perform_writes(drive, n):
             pattern.offset,
             pattern.size)
         log(cmd)
-        log(drive.vm.hmp_qemu_io(drive.node, cmd))
+        log(drive.vm.hmp_qemu_io(filter_node_name or drive.node, cmd))
     bitmaps = drive.vm.query_bitmaps()
     log({'bitmaps': bitmaps}, indent=2)
     log('')
@@ -355,7 +356,7 @@ def test_bitmap_sync(bsync_mode, msync_mode='bitmap', failure=None):
             """Issue writes while the job is open to test bitmap divergence."""
             # Note: when `failure` is 'intermediate', this isn't called.
             log('')
-            bitmaps = perform_writes(drive0, 2)
+            bitmaps = perform_writes(drive0, 2, filter_node_name='backup-top')
             # Named bitmap (static, should be unchanged)
             ebitmap.compare(vm.get_bitmap(drive0.node, 'bitmap0',
                                           bitmaps=bitmaps))
diff --git a/tests/qemu-iotests/257.out b/tests/qemu-iotests/257.out
index ec7e25877b..64dd460055 100644
--- a/tests/qemu-iotests/257.out
+++ b/tests/qemu-iotests/257.out
@@ -30,7 +30,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -78,7 +78,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -92,7 +92,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -205,7 +205,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -219,7 +219,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -290,7 +290,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -338,7 +338,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -354,7 +354,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 {"data": {"action": "report", "device": "backup_1", "operation": "read"}, "event": "BLOCK_JOB_ERROR", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "backup_1", "error": "Input/output error", "len": 393216, "offset": 65536, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
@@ -416,7 +416,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -430,7 +430,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -501,7 +501,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -549,7 +549,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -563,7 +563,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -676,7 +676,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -690,7 +690,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -761,7 +761,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -809,7 +809,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -823,7 +823,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -936,7 +936,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -950,7 +950,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -1021,7 +1021,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1069,7 +1069,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1085,7 +1085,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 {"data": {"action": "report", "device": "backup_1", "operation": "read"}, "event": "BLOCK_JOB_ERROR", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "backup_1", "error": "Input/output error", "len": 393216, "offset": 65536, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
@@ -1147,7 +1147,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1161,7 +1161,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -1232,7 +1232,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1280,7 +1280,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1294,7 +1294,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -1407,7 +1407,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1421,7 +1421,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -1492,7 +1492,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1540,7 +1540,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1554,7 +1554,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -1667,7 +1667,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1681,7 +1681,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -1752,7 +1752,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1800,7 +1800,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1816,7 +1816,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 {"data": {"action": "report", "device": "backup_1", "operation": "read"}, "event": "BLOCK_JOB_ERROR", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "backup_1", "error": "Input/output error", "len": 393216, "offset": 65536, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
@@ -1878,7 +1878,7 @@ expecting 13 dirty sectors; have 13. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -1892,7 +1892,7 @@ expecting 13 dirty sectors; have 13. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -1963,7 +1963,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2011,7 +2011,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2025,7 +2025,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "bitmap", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -2138,7 +2138,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2152,7 +2152,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -2223,7 +2223,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2271,7 +2271,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2285,7 +2285,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -2398,7 +2398,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2412,7 +2412,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -2483,7 +2483,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2531,7 +2531,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2547,7 +2547,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
 {"return": {}}
 {"data": {"action": "report", "device": "backup_1", "operation": "read"}, "event": "BLOCK_JOB_ERROR", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "backup_1", "error": "Input/output error", "len": 67108864, "offset": 983040, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
@@ -2609,7 +2609,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2623,7 +2623,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -2694,7 +2694,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2742,7 +2742,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2756,7 +2756,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -2869,7 +2869,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -2883,7 +2883,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -2954,7 +2954,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3002,7 +3002,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3016,7 +3016,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -3129,7 +3129,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3143,7 +3143,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -3214,7 +3214,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3262,7 +3262,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3278,7 +3278,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
 {"return": {}}
 {"data": {"action": "report", "device": "backup_1", "operation": "read"}, "event": "BLOCK_JOB_ERROR", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "backup_1", "error": "Input/output error", "len": 67108864, "offset": 983040, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
@@ -3340,7 +3340,7 @@ expecting 1014 dirty sectors; have 1014. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3354,7 +3354,7 @@ expecting 1014 dirty sectors; have 1014. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -3425,7 +3425,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3473,7 +3473,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3487,7 +3487,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "full", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -3600,7 +3600,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3614,7 +3614,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -3685,7 +3685,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3733,7 +3733,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3747,7 +3747,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -3860,7 +3860,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3874,7 +3874,7 @@ expecting 15 dirty sectors; have 15. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -3945,7 +3945,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -3993,7 +3993,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4009,7 +4009,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
 {"return": {}}
 {"data": {"action": "report", "device": "backup_1", "operation": "read"}, "event": "BLOCK_JOB_ERROR", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "backup_1", "error": "Input/output error", "len": 458752, "offset": 65536, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
@@ -4071,7 +4071,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4085,7 +4085,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -4156,7 +4156,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4204,7 +4204,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4218,7 +4218,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -4331,7 +4331,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4345,7 +4345,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -4416,7 +4416,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4464,7 +4464,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4478,7 +4478,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -4591,7 +4591,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4605,7 +4605,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -4676,7 +4676,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4724,7 +4724,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4740,7 +4740,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
 {"return": {}}
 {"data": {"action": "report", "device": "backup_1", "operation": "read"}, "event": "BLOCK_JOB_ERROR", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 {"data": {"device": "backup_1", "error": "Input/output error", "len": 458752, "offset": 65536, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
@@ -4802,7 +4802,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4816,7 +4816,7 @@ expecting 14 dirty sectors; have 14. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -4887,7 +4887,7 @@ write -P0x76 0x3ff0000 0x10000
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_0", "sync": "full", "target": "ref_target_0"}}
 {"return": {}}
 {"data": {"device": "ref_backup_0", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4935,7 +4935,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_1", "sync": "full", "target": "ref_target_1"}}
 {"return": {}}
 {"data": {"device": "ref_backup_1", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -4949,7 +4949,7 @@ expecting 6 dirty sectors; have 6. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_1", "sync": "top", "target": "backup_target_1"}}
 {"return": {}}
 
 --- Write #2 ---
@@ -5062,7 +5062,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "ref_backup_2", "sync": "full", "target": "ref_target_2"}}
 {"return": {}}
 {"data": {"device": "ref_backup_2", "len": 67108864, "offset": 67108864, "speed": 0, "type": "backup"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
 
@@ -5076,7 +5076,7 @@ expecting 12 dirty sectors; have 12. OK!
 {"execute": "job-dismiss", "arguments": {"id": "bdc-fmt-job"}}
 {"return": {}}
 {}
-{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
+{"execute": "blockdev-backup", "arguments": {"auto-finalize": false, "bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "backup_2", "sync": "bitmap", "target": "backup_target_2"}}
 {"return": {}}
 {"execute": "job-finalize", "arguments": {"id": "backup_2"}}
 {"return": {}}
@@ -5139,155 +5139,155 @@ qemu_img compare "TEST_DIR/PID-img" "TEST_DIR/PID-fbackup2" ==> Identical, OK!
 
 -- Sync mode incremental tests --
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'incremental' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'incremental' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'incremental' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'incremental' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be 'on-success' when using sync mode 'incremental'"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be 'on-success' when using sync mode 'incremental'"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be 'on-success' when using sync mode 'incremental'"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "incremental", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be 'on-success' when using sync mode 'incremental'"}}
 
 -- Sync mode bitmap tests --
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'bitmap' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'bitmap' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'bitmap' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "must provide a valid bitmap name for 'bitmap' sync mode"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "bitmap", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be given when providing a bitmap"}}
 
 -- Sync mode full tests --
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode 'never' has no meaningful effect when combined with sync mode 'full'"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "full", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be given when providing a bitmap"}}
 
 -- Sync mode top tests --
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode 'never' has no meaningful effect when combined with sync mode 'top'"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "top", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be given when providing a bitmap"}}
 
 -- Sync mode none tests --
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Cannot specify bitmap sync mode without a bitmap"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap404", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap 'bitmap404' could not be found"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "on-success", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "sync mode 'none' does not produce meaningful bitmap outputs"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "always", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "sync mode 'none' does not produce meaningful bitmap outputs"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "bitmap-mode": "never", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "sync mode 'none' does not produce meaningful bitmap outputs"}}
 
-{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
+{"execute": "blockdev-backup", "arguments": {"bitmap": "bitmap0", "device": "drive0", "filter-node-name": "backup-top", "job-id": "api_job", "sync": "none", "target": "backup_target"}}
 {"error": {"class": "GenericError", "desc": "Bitmap sync mode must be given when providing a bitmap"}}
 
-- 
2.21.0

Re: [PATCH v15 5/5] block/backup: use backup-top instead of write notifiers

[Max Reitz]

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On 01.10.19 15:14, Vladimir Sementsov-Ogievskiy wrote:
> Drop write notifiers and use filter node instead.
> 
> = Changes =
> 
> 1. Add filter-node-name argument for backup qmp api. We have to do it
> in this commit, as 257 needs to be fixed.
> 
> 2. There are no more write notifiers here, so is_write_notifier
> parameter is dropped from block-copy paths.
> 
> 3. To sync with in-flight requests at job finish we now have drained
> removing of the filter, we don't need rw-lock.
> 
> 4. Block-copy is now using BdrvChildren instead of BlockBackends
> 
> 5. As backup-top owns these children, we also move block-copy state
> into backup-top's ownership.
> 
> = Iotest changes =
> 
> 56: op-blocker doesn't shoot now, as we set it on source, but then
> check on filter, when trying to start second backup.
> To keep the test we instead can catch another collision: both jobs will
> get 'drive0' job-id, as job-id parameter is unspecified. To prevent
> interleaving with file-posix locks (as they are dependent on config)
> let's use another target for second backup.
> 
> Also, it's obvious now that we'd like to drop this op-blocker at all
> and add a test-case for two backups from one node (to different
> destinations) actually works. But not in these series.
> 
> 141: Output changed: prepatch, "Node is in use" comes from bdrv_has_blk
> check inside qmp_blockdev_del. But we've dropped block-copy blk
> objects, so no more blk objects on source bs (job blk is on backup-top
> filter bs). New message is from op-blocker, which is the next check in
> qmp_blockdev_add.
> 
> 257: The test wants to emulate guest write during backup. They should
> go to filter node, not to original source node, of course. Therefore we
> need to specify filter node name and use it.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  qapi/block-core.json       |   8 +-
>  include/block/block-copy.h |  14 +-
>  include/block/block_int.h  |   1 +
>  block/backup-top.c         |  21 +--
>  block/backup.c             |  73 +++------
>  block/block-copy.c         |  81 +++-------
>  block/replication.c        |   2 +-
>  blockdev.c                 |   1 +
>  tests/qemu-iotests/056     |   8 +-
>  tests/qemu-iotests/141.out |   2 +-
>  tests/qemu-iotests/257     |   7 +-
>  tests/qemu-iotests/257.out | 306 ++++++++++++++++++-------------------
>  12 files changed, 237 insertions(+), 287 deletions(-)

[...]

> diff --git a/block/block-copy.c b/block/block-copy.c
> index fcb112da14..5404bc921d 100644
> --- a/block/block-copy.c
> +++ b/block/block-copy.c

[...]

> @@ -218,8 +183,8 @@ static int coroutine_fn block_copy_with_offload(BlockCopyState *s,
>      nr_clusters = DIV_ROUND_UP(nbytes, s->cluster_size);
>      bdrv_reset_dirty_bitmap(s->copy_bitmap, start,
>                              s->cluster_size * nr_clusters);
> -    ret = blk_co_copy_range(s->source, start, s->target, start, nbytes,
> -                            read_flags, s->write_flags);
> +    ret = bdrv_co_copy_range(s->source, start, s->target, start, nbytes,
> +                            0, s->write_flags);

The indentation’s off here.  I’ll fix it.

Reviewed-by: Max Reitz <mreitz@redhat.com>


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Re: [PATCH v15 0/5] backup-top filter driver for backup

[Max Reitz]

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On 01.10.19 15:14, Vladimir Sementsov-Ogievskiy wrote:
> Hi all!
> 
> These series introduce backup-top driver. It's a filter-node, which
> do copy-before-write operation. Mirror uses filter-node for handling
> guest writes, let's move to filter-node (from write-notifiers) for
> backup too.
> 
> Preparation patches are queued in Max's block branch:
> 
> Based-on: https://github.com/XanClic/qemu.git block
> 
> v15: use BdrvChildren in block-copy
> 01-03: new
> 04-05: a lot of changes, such as
> 04:
>     - add new parameters for creation
>     - prepare bcs creation
>     - add target child
>     - refactor bdrv_backup_top_append
>     - drop r-b
> 05:
>     - move block-copy to use BdrvChildren
>     - drop extra style fixing hunks
>     - iotest 141 output changed
> 
> v14: Drop range locks, keep old good in-flight requests waiting
> 
> 12: new patch
> 14: use old request-waiting scheme instead of range locks
> 
> Vladimir Sementsov-Ogievskiy (5):
>   block/backup: move in-flight requests handling from backup to
>     block-copy
>   block/backup: move write_flags calculation inside backup_job_create
>   block/block-copy: split block_copy_set_callbacks function
>   block: introduce backup-top filter driver
>   block/backup: use backup-top instead of write notifiers
> 
>  qapi/block-core.json       |   8 +-
>  block/backup-top.h         |  41 +++++
>  include/block/block-copy.h |  31 +++-
>  include/block/block_int.h  |   1 +
>  block/backup-top.c         | 276 +++++++++++++++++++++++++++++++++
>  block/backup.c             | 147 +++++-------------
>  block/block-copy.c         | 140 +++++++++--------
>  block/replication.c        |   2 +-
>  blockdev.c                 |   1 +
>  block/Makefile.objs        |   1 +
>  tests/qemu-iotests/056     |   8 +-
>  tests/qemu-iotests/141.out |   2 +-
>  tests/qemu-iotests/257     |   7 +-
>  tests/qemu-iotests/257.out | 306 ++++++++++++++++++-------------------
>  14 files changed, 628 insertions(+), 343 deletions(-)
>  create mode 100644 block/backup-top.h
>  create mode 100644 block/backup-top.c

Thanks, applied to my block branch:

https://git.xanclic.moe/XanClic/qemu/commits/branch/block

Max


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Re: [PATCH v15 0/5] backup-top filter driver for backup

[Vladimir Sementsov-Ogievskiy]

04.10.2019 17:21, Max Reitz wrote:
> On 01.10.19 15:14, Vladimir Sementsov-Ogievskiy wrote:
>> Hi all!
>>
>> These series introduce backup-top driver. It's a filter-node, which
>> do copy-before-write operation. Mirror uses filter-node for handling
>> guest writes, let's move to filter-node (from write-notifiers) for
>> backup too.
>>
>> Preparation patches are queued in Max's block branch:
>>
>> Based-on: https://github.com/XanClic/qemu.git block
>>
>> v15: use BdrvChildren in block-copy
>> 01-03: new
>> 04-05: a lot of changes, such as
>> 04:
>>      - add new parameters for creation
>>      - prepare bcs creation
>>      - add target child
>>      - refactor bdrv_backup_top_append
>>      - drop r-b
>> 05:
>>      - move block-copy to use BdrvChildren
>>      - drop extra style fixing hunks
>>      - iotest 141 output changed
>>
>> v14: Drop range locks, keep old good in-flight requests waiting
>>
>> 12: new patch
>> 14: use old request-waiting scheme instead of range locks
>>
>> Vladimir Sementsov-Ogievskiy (5):
>>    block/backup: move in-flight requests handling from backup to
>>      block-copy
>>    block/backup: move write_flags calculation inside backup_job_create
>>    block/block-copy: split block_copy_set_callbacks function
>>    block: introduce backup-top filter driver
>>    block/backup: use backup-top instead of write notifiers
>>
>>   qapi/block-core.json       |   8 +-
>>   block/backup-top.h         |  41 +++++
>>   include/block/block-copy.h |  31 +++-
>>   include/block/block_int.h  |   1 +
>>   block/backup-top.c         | 276 +++++++++++++++++++++++++++++++++
>>   block/backup.c             | 147 +++++-------------
>>   block/block-copy.c         | 140 +++++++++--------
>>   block/replication.c        |   2 +-
>>   blockdev.c                 |   1 +
>>   block/Makefile.objs        |   1 +
>>   tests/qemu-iotests/056     |   8 +-
>>   tests/qemu-iotests/141.out |   2 +-
>>   tests/qemu-iotests/257     |   7 +-
>>   tests/qemu-iotests/257.out | 306 ++++++++++++++++++-------------------
>>   14 files changed, 628 insertions(+), 343 deletions(-)
>>   create mode 100644 block/backup-top.h
>>   create mode 100644 block/backup-top.c
> 
> Thanks, applied to my block branch:
> 
> https://git.xanclic.moe/XanClic/qemu/commits/branch/block
> 
> Max
> 

Yay!! Thank you!

-- 
Best regards,
Vladimir